title: Horatio Caine

text: In early seasons, Horatio frequently confirms his dedication to the job with the catchphrase "We Never Close", an homage to the Pinkerton Agency. Horatio is known for wearing sunglasses (known by fans as the 'Shades of Justice'); one of his trademarks is to put them on prior to making a dramatic remark. In season 8, it is revealed that this style of sunglasses were originally a gift from Eric Delko in 1997.


title: Horatio Caine

text: In season 4, Horatio began a romantic relationship with Marisol Delko (Eric's sister). Horatio and Marisol got married and she was killed by the end of season 4.


title: Horatio Caine

text: In the season nine finale, Horatio is shot down by Randy North, the unwilling accomplice of convicted felon Jack Toller, who also kidnaps Horatio's co-worker Natalia Boa Vista and puts her in the trunk of a car and pushes it off the pier. In the tenth-season premiere, Horatio manages to save Natalia and, with the team, captures Toller.


title: Horatio Caine

text: In the CSI continuum, Horatio is a day shift supervisor at the Miami-Dade crime lab, a forensic analyst and former homicide detective and bomb squad officer (his forensic specialty is arson and explosion evidence). He is very protective of his team, who affectionately call him "H". He is very concerned about the reputation of his lab, and takes great care to keep them clean, likely because of his experience with his tarnished younger brother, Ray. When his staff fall under suspicion in several episodes ("One of Our Own", ""), he immediately jumps in their defense, especially from IA investigator Rick Stetler, and tries his best to prove their innocence.


title: Horatio Caine

text: Unlike his counterpart in Las Vegas, now former CSI Supervisor Gil Grissom (""), he is a sworn police officer, and thus carries a badge and gun. A superb marksman, Horatio doesn't hesitate to use deadly force when the situation calls for it. He is also an ardent advocate of the death penalty for particularly heinous crimes, and doesn't think twice about threatening suspects with it in such cases. He is also known to reserve an especially deep wrath for those who would dare to harm children. Horatio is truly egalitarian, treating all victims and their families equally, regardless of their ethnicity, background, or economic station. He often goes out of his way to ensure they are alright during the course of a case, especially when it involves a child, frequently giving his number to them, stating that he is available day or night to take their call. On top of providing himself with a comfortable living, Horatio has helped others financially with such expensive things as providing private funeral arrangements for an indigent murder victim, rent and living expenses for his brother Ray's mistress and his niece, as well as medical costs for his niece's cancer treatment, purchasing an apartment for his son Kyle, despite being a civil servant on a county wage. This is likely due to a number of extremely shrewd financial decisions and deals Horatio made over the years leading up to the series.


title: Horatio Caine

text: In the first two seasons, Horatio carries a Beretta Cougar on the job. Since the beginning of season three, he has been shown carrying a SIG Sauer P229. He is very insistent on gun maintenance, especially since team member Tim Speedle was killed in a shootout after his gun misfired because of his lax maintenance. In fact, one of the reasons for Horatio's nearly on-the-spot selection of Officer Ryan Wolfe as Tim Speedle's replacement (in episode 303, "Under the Influence") is Wolfe's compulsive care of his firearm due to OCD.


title: Horatio Caine

text: He is later forced to fire Wolfe, as the younger CSI compromised himself during the course of the investigation due to his gambling debts and lack of honesty regarding the situation (episode 522, "Burned"). Wolfe also previously violated protocol. Horatio indicates a willingness to allow Wolfe to redeem himself, however, and possibly allow him to return to the team after reviewing all the files from his previous cases (episode 523, "Kill Switch").


title: Horatio Caine

text: At the end of Season 2 (episode 223, "MIA/NYC — Nonstop"), Horatio travels to New York City in pursuit of a murder suspect and meets Detective Mac Taylor and his team, inaugurating the first season of "". Horatio later reunites with Mac and the New York CSIs to track down and arrest the murderer, Henry Darius, who would be extradited to Florida to face the death penalty ("CSI: Miami" episode 407, "Felony Flight," "" episode 207, "Manhattan Manhunt"). This appearance would make Horatio Caine the first character to appear at least once in all three CSI shows.


title: Horatio Caine

text: He has many recurring enemies throughout the series, from serial killer Walter Resden to abusive internal affairs agent Rick Stetler to corrupt judge Joseph Ratner. Some he thought had been put away for good come back to haunt him. Clavo Cruz, serving a life sentence for murdering a woman (episode 201, "Blood Brothers," episode 315, "Identity"), escapes custody in a dramatic rocket attack on a courthouse (superficially injuring coroner Alexx Woods). Cruz then kidnaps a court stenographer and forces Horatio to bring him $1 million in exchange for her location. It is all a set-up, however, and Horatio and Delko are ambushed on the roof of a parking garage. Though Horatio shoots down one man and escapes without injury, Delko is critically wounded even as Horatio fires at the fleeing gunmen (episode 514, "No Man's Land"). Horatio eventually forces Cruz out of hiding by removing all his avenues of escape. Cruz approaches Horatio outside the Miami-Dade Crime Lab, and Horatio kills Clavo with a single shot to the chest (episode 515, "Man Down").


title: Horatio Caine

text: In episode 302 ("Pro Per"), Yelina's house was shot but she and Ray Jr. were unharmed because previously Horatio had warned of them. The attackers were captured and although the danger had passed, Horatio offered her to stay out all night watching the house but Yelina said him that it wasn't necessary. In that moment, to Horatio's surprise, Rick Stetler leaves the house with Ray Jr. Horatio was deeply disappointed.


title: Horatio Caine

text: In episode 406 ("Under Suspicion"), Rachel Turner, Horatio's girlfriend, is murdered. He is suspected of the murder because he was the last person to see the victim alive. Later, the true killer was found, he was Walter Resden, an old enemy of Horatio.


title: Horatio Caine

text: In the episode 412 ("The Score"), Marisol Delko invited Horatio to have dinner but he refused at first, because she had just been cleared in a drug investigation and he, as head of the lab, could be put under scrutinity. He ended up accepting the invitation, and the two later started their relationship.


title: Horatio Caine

text: Horatio finds himself targeted by the son of Argento, a crime lord whom he helped put in jail some years earlier. After the young man vandalizes Horatio's vehicle, then smugly denies culpability; he then shoots the Lieutenant. However, the rounds from his gun were replaced with blanks, Horatio leaves without injury and the son is arrested afterward (episode 602, "Cyber-lebrity").


title: Horatio Caine

text: In the episode "Bone Voyage", when Raymond Langston comes to help Horatio and his team, he mentions deceased CSI Warrick Brown and asks Langston to tell Catherine Willows that he is sorry for their loss.


title: Horatio Caine

text: In the end of the Season 8 finale, Horatio receives a shocking message from the man he arrested. The message said: "THEY ALL FALL DOWN". In the Season 9 premiere, he rushes to the crime lab, fearing for the team's lives. When he got out of the elevator, he finds everyone down and Eric barely conscious. Eric tells him to shoot the windows out for oxygen. After Horatio does so, everyone gets back to their feet, except for Jesse Cardoza, who dies from his fall to the floor. Horatio then tries to comfort the devastated Natalia, who unsuccessfully attempted to revive Cardoza. Horatio finds the killer, and then joins the team on a game of basketball, in honor of Cardoza.


title: Horatio Caine

text: In "See No Evil" a large prison break occurs and one of the inmates, Joe LeBrock, states that they were planning on targeting Horatio.


title: Horatio Caine

text: In the episode "Manhunt", he and the team track down Memmo Fierro, the man who was serving time for killing Marisol (Horatio's wife and Eric's sister) after he is one of the eight people who broke out in the previous episode. Memmo (under orders of Antonio Riaz of the Mala Noche) had shot Marisol, then blocked the ambulance, trying to get Horatio to come out, forcing the ambulance to drive over a center median. At the hospital, a doctor states that the car was worse than the bullet. Both the shooting and the blocking proved fatal to Marisol. At the end of the episode, Memmo takes a hostage, his daughter's social worker. Eric has a clear shot of him, but Horatio tells him not to shoot him in front of Memmo's daughter. After Memmo sees his daughter, he leaves with the hostage, who is later found dead.


title: Horatio Caine

text: In "Happy Birthday", Horatio is seen driving at the beginning of the episode with a bouquet of flowers on the passenger seat and leaves Eric a message on his phone asking him to take over from him for a while so he can run an errand. He is distracted by a pedestrian, who informs him a pregnant woman has been assaulted on the side of the road. Leaving his errand behind, he helps the woman and spends the rest of the episode looking for the people who did this to her, while the mother and the baby are fighting for their life back in the hospital. At the end of the episode, the mother gives birth to a baby girl, and her husband is arrested because he did not want her to have the baby and rigged the car to so that she would hit the steering wheel in her midsection during a staged car accident & force a miscarriage. We see Horatio at Marisol's grave; he tells her the baby is "beautiful, just like you". He then wishes her 'happy birthday'. Marisol's murder caused him a big feeling of guilt because he couldn't protect her and that idea obsessed him a long time after her death.


title: Horatio Caine

text: In "Last Stand", Memmo returns with a gang of drug cartels, and Horatio lays a trap for him, alone. Horatio kicks Memmo multiple times and holds him at gunpoint. Memmo states to him that killing his wife was not personal, but Horatio responds that it was to him. Memmo asks if what Caine is doing is "righteous" and if he is at peace with his decision. Horatio responds that he is, and places him under arrest, and waits for backup to arrive.


title: Horatio Caine

text: In "Crowned", Horatio does not help a kidnapper, who kidnapped a girl who participated in a child's beauty pageants, and lets him fall off the edge at an abandoned movie theater, after shooting him (not fatally).


title: Horatio Caine

text: Over recent years and presumably due to the fact that he was left gravely injured after being shot, Horatio has become more aggressive than usual when it comes to dealing with suspects and he has been seen on at least two occasions apparently assaulting a suspect in a locked room (the actual assault is only implied as it takes place off camera). In both these cases the suspect was accused of abuse (one child molestation, the other domestic violence).


title: Horatio Caine

text: Further evidence of this can be found in the season 8 episode "Kill Clause", the ending of which implies that Horatio has sanctioned the murder of a corrupt CEO who had his employees murdered for their life insurance.


title: Horatio Caine

text: Caruso's performance as Horatio Caine received very positive feedback from critics. The Character became one of few fan favorite characters in the "CSI" franchise. On an episode of the "Late Show with David Letterman" that aired on March 8, 2007, comedian Jim Carrey professed to being a fan of the show and went on to satirically impersonate Caruso's character, which received praise from Caruso.


title: Deer in mythology

text: Deer have significant roles in the mythology of various peoples located all over the world, such as object of worship, the incarnation of deities, the object of heroic quests and deeds, or as magical disguise or enchantment/curse for princesses and princes in many folk and fairy tales.


title: Deer in mythology

text: The deer also symbolizes a connection to the supernatural, the Otherworld or to the fairy realm, e.g., being a messenger or an entity's familiar.


title: Deer in mythology

text: A deer or a doe (female deer) usually appears in fairy tales as the form of a princess who has been enchanted by a malevolent fairy or witch, such as "The White Doe" (French fairy tale) and "The Enchanted Deer" (Scottish fairy tale), or a transformation curse a male character falls under. Sometimes, it represents a disguise a prince dons to escape or to achieve a goal, e.g., What the Rose did to the Cypress (Persian fairy tale). Tale types that include a transformation into deer or hind are ATU 401, "The Princess Transformed into Deer" and ATU 450, "Brother and Sister" (male relative changed into deer; see: Brother and Sister, German fairy tale; The Golden Stag, Romanian fairy tale).


title: Deer in mythology

text: A deer also appears as a helper, such as in Italian fairy tale "The Dancing Water, the Singing Apple, and the Speaking Bird", as a foster mother to the exposed twin children; or in Portuguese folktale "The Hind of the Golden Apple", as a talking animal who gifts the hero with the titular golden apple. It also may appear as a disguised adversary (an ogre, a sorcerer), e.g., in "The Enchanted Doe" (Italian literary fairy tale), or as a malevolent seductress, e.g., in Indian fairy tale "The Son of Seven Queens", collected by Joseph Jacobs.


title: Deer in mythology

text: The deer also appears as a character in Animal fables, e.g., "The Deer without a Heart" (Indian fable) and "The Stag at the Pool" (attributed to Aesop). Another cervine animal, the stag, appears in an etiological tale from Brazil ("Why the Tiger and the Stag hate each other").


title: Deer in mythology

text: In one of the Jataka tales, Buddha has reincarnated into the form of a deer. This story has many incarnations and names itself: such as "The Story of Ruru Deer", "The Golden Deer", and the Chinese cartoon "A Deer of Nine Colors". The story originated in India around the 4th century BCE. The narrative hails the merits of compassion, empathy, and karma.


title: Deer in mythology

text: The Insular Celts have stories involving supernatural deer, deer who are associated with a spiritual figure, and spirits or deities who may take the form of deer.


title: Deer in mythology

text: In some Scottish and Irish tales deer are seen as "fairy cattle" and are herded and milked by a tutelary, benevolent, otherworldly woman (such as a "bean sìdhe" or in other cases the goddess Flidais), who can shapeshift into the form of a red or white deer. In the West Highlands, this woman of the otherworld selects the individual deer who will be slain in the next day's hunt.


title: Deer in mythology

text: In Ireland, The "Cailleach Bhéara" ("The Old Woman of Beare"), who lives on an island off the coast of County Cork, takes the form of a deer to avoid capture, and herds her deer down by the shore. The Beare peninsula is also associated with the islands in the western sea that are the lands of the dead. Other Celtic mythological figures such as Oisín and Sadhbh also have connections to deer.


title: Deer in mythology

text: Cernunnos is a mythological figure in Continental Celtic mythology, and possibly one of the figures depicted on the Gundestrup cauldron. He has stag antlers on the top of his head. His role in the religion and mythology is unclear, as there are no particular stories about him.


title: Deer in mythology

text: Medieval works of fiction sometimes contain the existence of a white deer or stag as a supernatural or mystical being in the chivalry quest ("The Hunt for the White Stag" motif, such as in the "lai" of "Guigemar") and in parts of Arthurian lore, such as in the medieval poem of "Erec and Enide".


title: Deer in mythology

text: Saint Giles, a Catholic saint especially revered in the south of France, is reported to have lived for many years as a hermit in the forest near Nîmes, where in the greatest solitude he spent many years, his sole companion being a deer, or hind, who in some stories sustained him on her milk. In art, he is often depicted together with that hind.


title: Deer in mythology

text: Deer figure in the founding legend of Le Puy-en-Velay, where a Christian church replaced a megalithic dolmen said to have healing powers. A local tradition had rededicated the curative virtue of the sacred site to Mary, who cured ailments by contact with the standing stone. When the founding bishop Vosy climbed the hill, he found that it was snow-covered in July; in the snowfall, the tracks of a deer around the dolmen outlined the foundations of the future church.


title: Deer in mythology

text: In the story of Saint Hubertus, on Good Friday morning, when the faithful were crowding the churches, Hubertus sallied forth to the chase. As he was pursuing a magnificent stag the animal turned and, as the pious legend narrates, he was astounded at perceiving a crucifix standing between its antlers, which occasioned the change of heart that led him to a saintly life. The story of the hart appears first in one of the later legendary hagiographies ("Bibliotheca hagiographica Latina", nos. 3994–4002) and has been appropriated from the earlier legend of Saint Eustace (Placidus).


title: Deer in mythology

text: Later in the 6th century, the Bishop Saint Gregory of Tours wrote his chronicles about the Merovingian rulers. "Historia Francorum" contains the legend of King Clovis I, who prayed to Christ in one of his campaigns so he could find a place to cross the river Vienne. Considered as a divine sign, a huge deer appeared and showed where the army could pass.


title: Deer in mythology

text: In the 14th century, probably keeping some relation with Saint Eustace's legend, the deer again appears in Christian legend. The "Chronicon Pictum" contains a story where the later King Saint Ladislaus I of Hungary and his brother the King Géza I of Hungary were hunting in a forest, and a deer with numerous candles on his antlers appeared to them. Saint Ladislaus told his brother that it wasn't a deer but an angel of God, and his antlers were wings; the candles were shining feathers. He also stated his intent to build a cathedral in honor of the Holy Virgin in the place where the deer appeared.


title: Deer in mythology

text: An Anglo-Saxon royal scepter found at the Sutton Hoo burial site in England features a depiction of an upright, antlered stag. In the Old English language poem "Beowulf", much of the first portion of the story focuses on events surrounding a great mead hall called Heorot, meaning "Hall of the Hart".


title: Deer in mythology

text: In the "Poetic Edda" poem "Grímnismál" the four stags of Yggdrasil are described as feeding on the world tree, Yggdrasil, and the poem further relates that the stag Eikþyrnir lives on top of Valhalla. In the "Prose Edda" book "Gylfaginning", the god Freyr is having once killed Beli with an antler. In "Þiðrekssaga", Sigurd is presented as having been nursed by a doe.


title: Deer in mythology

text: Andy Orchard proposes a connection between the hart Eikþyrnir atop Valhalla, the hart imagery associated with Heorot, and the Sutton Hoo scepter. Sam Newton identifies both the Sutton Hoo whetstone and the hall Heorot as early English symbols of kingship. Rudolf Simek says that "it is not completely clear what role the stag played in Germanic religion" and theorizes that "the stag cult probably stood in some sort of connexion to Odin's endowment of the dignity of kings."


title: Deer in mythology

text: In Greek mythology, the deer is particularly associated with Artemis in her role as virginal huntress. Actaeon, after witnessing the nude figure of Artemis bathing in a pool, was transformed by Artemis into a stag that his own hounds tore to pieces. Callimachus, in his archly knowledgeable "Hymn III to Artemis", mentions the deer that drew the chariot of Artemis:


title: Deer in mythology

text: One of the Labors of Heracles was to capture the Ceryneian Hind sacred to Artemis and deliver it briefly to his patron, then rededicate it to Artemis. As a hind bearing antlers was unknown in Greece, the story suggests a reindeer, which, unlike other deer, can be harnessed and whose females bear antlers. The myth relates to Hyperborea, a northern land that would be a natural habitat for reindeer. Heracles' son Telephus was exposed as an infant on the slopes of Tegea but nurtured by a doe.


title: Deer in mythology

text: In Hindu mythology, the Aitareya Upanishad tells us that the goddess Saraswati takes the form of a red deer called Rohit. Saraswati is the goddess of learning, so learned men use deer skin as clothing and mats to sit upon. A golden deer plays an important role in the epic "Ramayana". While in exile in the forest, Rama's wife Sita sees a golden deer and asks Rama and Lakshmana to get it for her. The deer is actually a rakshasa called Maricha in disguise. Maricha takes this form to lure Rama and Lakshmana away from Sita so his nephew Ravana can kidnap her.


title: Deer in mythology

text: South-Indian icons of the Hindu god Shiva may be depicted holding a deer in a hand. In the iconography of Shiva's mendicant form Bhikshatana, a deer playfully leaps near a hand of the god, who holds some grass. The deer also appears in icons of another form Kankalamurti, who is depicted similar to Bhikshatana.


title: Deer in mythology

text: The stag was revered alongside the bull at Alaca Höyük and continued in the Hittite mythology as the protective deity whose name is recorded as "KAL". Other Hittite gods were often depicted standing on the backs of stags, such as Kurunta or fellow Anatolian (Luwian) deity Runtiya. The deers would also have a long standing rivalry with the mountains in Hittite mythology


title: Deer in mythology

text: For the Huichol people of Mexico, the "magical deer" represents both the power of maize to sustain the body and of the peyote cactus to feed and enlighten the spirit. Animals such as the eagle, jaguar, serpent and deer are of great importance to the Mexican indigenous cultures. For each group, however, one of these animals is of special significance and confers some of its qualities to the tribe.


title: Deer in mythology

text: For the Huichol it is the deer that holds this intimate role. The character of the Huichol tends to be light, flexible and humorous. They have avoided open warfare, neither fighting against the Spanish nor Mexican governments, but holding to their own traditions. The Huichol hunt and sacrifice deer in their ceremonies. They make offerings to the Deer of the Maize to care for their crops, and to the Deer of the Peyote to bring them spiritual guidance and artistic inspiration.


title: Deer in mythology

text: In Hungarian mythology, Hunor and Magor, the founders of the Magyar peoples, chased a white stag in a hunt. The stag lead them into unknown land that they named Scythia. Hunor and Magor populated Scythia with their descendants the Huns and the Magyars. To this day, an important emblem in Hungary is a many-antlered stag with its head turned back over its shoulder.


title: Deer in mythology

text: In the Ottoman Empire, and more specifically in western Asia Minor and Thrace the deer cult seems to have been widespread and much alive, no doubt as a result of the meeting and mixing of Turkic with local traditions. A famous case is the 13th century holy man Geyiklü Baba (ie. 'father deer'), who lived with his deer in the mountain forests of Bursa and gave hind's milk to a colleague. Material in the Ottoman sources is not scarce but it is rather dispersed and very brief, denying us a clear picture of the rites involved.


title: Deer in mythology

text: The Tribe Naftali bore a Stag on its tribal banner, and was poetically described as a Hind in the Blessing of Jacob.


title: Deer in mythology

text: In Jewish mythology – as discussed in the Talmud (חולין נט ע"ב) – exists a giant kind of stag by the name "Keresh". He is said to live in a mythical forest called "Bei Ilai".


title: Deer in mythology

text: The deer symbol also appears in the ancient Kurdish legends. Kurdish people still believe in that if they kill a deer it brings them bad luck. They think about this animal as a saint who belongs to God. They use it also as a national symbol. Nowadays Kurdistan Regional Government forbids hunting and killing deer.


title: Deer in mythology

text: In Native American mythology, there is the tale of the Deer Woman, a legendary creature associated with love and fertility.


title: Deer in mythology

text: In 1914, Hungarian composer Béla Bartók collected two Hungarian (Székely) "colinde" in Transylvania. The story is of a father who has taught his nine sons only how to hunt, so they know nothing of work and spend all of their time in the forest. One day while hunting a large and beautiful stag, they cross a haunted bridge and are themselves transformed into stags. The distressed father takes his rifle and goes out in search of his missing sons. Finding a group of fine stags gathered around a spring, he drops to one knee and takes aim. The largest stag (eldest son) pleads with his father not to shoot. The father, recognizing his favorite son in the stag, begs his children to come home. The stag then replies that they can never come home: their antlers cannot pass through doorways and they can no longer drink from cups, only cool mountain springs. Bartók prepared a Hungarian libretto, and in 1930 set the tale to music in his "Cantata Profana". It was first performed in London in 1934, in an English translation.


title: Deer in mythology

text: The Scythians had some reverence for the stag, which is one of the most common motifs in Scythian art. Possibly the swift animal was believed to speed the spirits of the dead on their way, which perhaps explains the curious antlered headdresses found on horses buried at Pazyryk ("illustration at the top of this article").


title: Deer in mythology

text: Golden or silver deer/elk was a popular folk character at the Urals in the 18th century. There were tales about the mythical creature called Silver Deer, also known as the elk Golden Horns and the goat Silver Hoof.


title: Deer in mythology

text: Deer are considered messengers to the gods in Shinto, especially Kasuga Shrine in Nara Prefecture where a white deer had arrived from Kashima Shrine as its divine messenger. It has become a symbol of the city of Nara. Deer in Itsukushima Shrine, located in Miyajima, Hiroshima, are also sacred as divine messengers. In various parts of Northeast Japan, a deer dance called "Shishi-odori" has been traditionally performed as an annual shinto ritual.


title: Deer in mythology

text: Quintus Sertorius, while a general in Lusitania, had a tame white stag which he had raised nearly from birth. Playing on the superstitions of the local tribes, he told them that it had been given to him by the goddess Diana; by attributing all his intelligence reports to the animal, he convinced the locals that it had the gift of prophecy. (See Plutarch's life of Sertorius and Pliny the Elder's chapter on stags [N.H., VIII.50])


title: Deer in mythology

text: The naming of Sir Francis Drake's ship the "Golden Hind" is sometimes given a mythological origin. However, Drake actually renamed his flagship in mid-voyage in 1577 to flatter his patron Sir Christopher Hatton, whose armorial bearings included the crest "a hind Or." In heraldry, a "hind" is a doe.


title: Deer in mythology

text: Rudolph the Red-Nosed Reindeer, as well as the rest of Santa Claus's reindeer, originated as fictional but have become an integral part of Western festive legend.


title: Fracture mechanics

text: Fracture mechanics is the field of mechanics concerned with the study of the propagation of cracks in materials. It uses methods of analytical solid mechanics to calculate the driving force on a crack and those of experimental solid mechanics to characterize the material's resistance to fracture.


title: Fracture mechanics

text: Theoretically, the stress ahead of a sharp crack tip becomes infinite and cannot be used to describe the state around a crack. Fracture mechanics is used to characterise the loads on a crack, typically using a single parameter to describe the complete loading state at the crack tip. A number of different parameters have been developed. When the plastic zone at the tip of the crack is small relative to the crack length the stress state at the crack tip is the result of elastic forces within the material and is termed linear elastic fracture mechanics (LEFM) and can be characterised using the stress intensity factor formula_1. Although the load on a crack can be arbitrary, in 1957 G. Irwin found any state could be reduced to a combination of three independent stress intensity factors:


title: Fracture mechanics

text: When the size of the plastic zone at the crack tip is too large, elastic-plastic fracture mechanics can be used with parameters such as the J-integral or the crack tip opening displacement.


title: Fracture mechanics

text: The characterising parameter describes the state of the crack tip which can then be related to experimental conditions to ensure similitude. Crack growth occurs when the parameters typically exceed certain critical values. Corrosion may cause a crack to slowly grow when the stress corrosion stress intensity threshold is exceeded. Similarly, small flaws may result in crack growth when subjected to cyclic loading. Known as fatigue, it was found that for long cracks, the rate of growth is largely governed by the range of the stress intensity formula_2 experienced by the crack due to the applied loading. Fast fracture will occur when the stress intensity exceeds the fracture toughness of the material. The prediction of crack growth is at the heart of the damage tolerance mechanical design discipline.


title: Fracture mechanics

text: The processes of material manufacture, processing, machining, and forming may introduce flaws in a finished mechanical component. Arising from the manufacturing process, interior and surface flaws are found in all metal structures. Not all such flaws are unstable under service conditions. Fracture mechanics is the analysis of flaws to discover those that are safe (that is, do not grow) and those that are liable to propagate as cracks and so cause failure of the flawed structure. Despite these inherent flaws, it is possible to achieve through damage tolerance analysis the safe operation of a structure. Fracture mechanics as a subject for critical study has barely been around for a century and thus is relatively new.


title: Fracture mechanics

text: Fracture mechanics was developed during World War I by English aeronautical engineer A. A. Griffith – thus the term Griffith crack – to explain the failure of brittle materials. Griffith's work was motivated by two contradictory facts:


title: Fracture mechanics

text: A theory was needed to reconcile these conflicting observations. Also, experiments on glass fibers that Griffith himself conducted suggested that the fracture stress increases as the fiber diameter decreases. Hence the uniaxial tensile strength, which had been used extensively to predict material failure before Griffith, could not be a specimen-independent material property. Griffith suggested that the low fracture strength observed in experiments, as well as the size-dependence of strength, was due to the presence of microscopic flaws in the bulk material.


title: Fracture mechanics

text: To verify the flaw hypothesis, Griffith introduced an artificial flaw in his experimental glass specimens. The artificial flaw was in the form of a surface crack which was much larger than other flaws in a specimen. The experiments showed that the product of the square root of the flaw length (formula_3) and the stress at fracture (formula_4) was nearly constant, which is expressed by the equation:


title: Fracture mechanics

text: An explanation of this relation in terms of linear elasticity theory is problematic. Linear elasticity theory predicts that stress (and hence the strain) at the tip of a sharp flaw in a linear elastic material is infinite. To avoid that problem, Griffith developed a thermodynamic approach to explain the relation that he observed.


title: Fracture mechanics

text: The growth of a crack, the extension of the surfaces on either side of the crack, requires an increase in the surface energy. Griffith found an expression for the constant formula_6 in terms of the surface energy of the crack by solving the elasticity problem of a finite crack in an elastic plate. Briefly, the approach was:


title: Fracture mechanics

text: where formula_8 is the Young's modulus of the material and formula_9 is the surface energy density of the material. Assuming formula_10 and formula_11 gives excellent agreement of Griffith's predicted fracture stress with experimental results for glass.


title: Fracture mechanics

text: For the simple case of a thin rectangular plate with a crack perpendicular to the load, the energy release rate, formula_12, becomes:


title: Fracture mechanics

text: where formula_14 is the applied stress, formula_3 is half the crack length, and formula_8 is the Young’s modulus, which for the case of plane strain should be divided by the plate stiffness factor formula_17. The strain energy release rate can physically be understood as: "the rate at which energy is absorbed by growth of the crack".


title: Fracture mechanics

text: For materials highly deformed before crack propagation, the linear elastic fracture mechanics formulation is no longer applicable and an adapted model is necessary to describe the stress and displacement field close to crack tip, such as on fracture of soft materials.


title: Fracture mechanics

text: "Griffith's work was largely ignored by the engineering community until the early 1950s. The reasons for this appear to be (a) in the actual structural materials the level of energy needed to cause fracture is orders of magnitude higher than the corresponding surface energy, and (b) in structural materials there are always some inelastic deformations around the crack front that would make the assumption of linear elastic medium with infinite stresses at the crack tip highly unrealistic."


title: Fracture mechanics

text: Griffith's theory provides excellent agreement with experimental data for brittle materials such as glass. For ductile materials such as steel, although the relation formula_21 still holds, the surface energy ("γ") predicted by Griffith's theory is usually unrealistically high. A group working under G. R. Irwin at the U.S. Naval Research Laboratory (NRL) during World War II realized that plasticity must play a significant role in the fracture of ductile materials.


title: Fracture mechanics

text: In ductile materials (and even in materials that appear to be brittle), a plastic zone develops at the tip of the crack. As the applied load increases, the plastic zone increases in size until the crack grows and the elastically strained material behind the crack tip unloads. The plastic loading and unloading cycle near the crack tip leads to the dissipation of energy as heat. Hence, a dissipative term has to be added to the energy balance relation devised by Griffith for brittle materials. In physical terms, additional energy is needed for crack growth in ductile materials as compared to brittle materials.


title: Fracture mechanics

text: where formula_9 is the surface energy and formula_24 is the plastic dissipation (and dissipation from other sources) per unit area of crack growth.


title: Fracture mechanics

text: For brittle materials such as glass, the surface energy term dominates and formula_26. For ductile materials such as steel, the plastic dissipation term dominates and formula_27. For polymers close to the glass transition temperature, we have intermediate values of formula_12 between 2 and 1000 formula_29.


title: Fracture mechanics

text: Another significant achievement of Irwin and his colleagues was to find a method of calculating the amount of energy available for fracture in terms of the asymptotic stress and displacement fields around a crack front in a linear elastic solid. This asymptotic expression for the stress field in mode I loading is related to the stress intensity factor formula_30 following:


title: Fracture mechanics

text: where formula_32 are the Cauchy stresses, formula_33 is the distance from the crack tip, formula_34 is the angle with respect to the plane of the crack, and formula_35 are functions that depend on the crack geometry and loading conditions. Irwin called the quantity formula_36 the stress intensity factor. Since the quantity formula_35 is dimensionless, the stress intensity factor can be expressed in units of formula_38.


title: Fracture mechanics

text: Stress intensity replaced strain energy release rate and a term called fracture toughness replaced surface weakness energy. Both of these terms are simply related to the energy terms that Griffith used:


title: Fracture mechanics

text: where formula_41 is the mode formula_42 stress intensity, formula_43 the fracture toughness, and formula_44 is Poisson’s ratio.


title: Fracture mechanics

text: Fracture occurs when formula_45. For the special case of plane strain deformation, formula_43 becomes formula_47 and is considered a material property. The subscript formula_42 arises because of the different ways of loading a material to enable a crack to propagate. It refers to so-called "mode formula_42" loading as opposed to mode formula_50 or formula_51:


title: Fracture mechanics

text: The expression for formula_41 will be different for geometries other than the center-cracked infinite plate, as discussed in the article on the stress intensity factor. Consequently, it is necessary to introduce a dimensionless correction factor, formula_53, in order to characterize the geometry. This correction factor, also often referred to as the "geometric shape factor", is given by empirically determined series and accounts for the type and geometry of the crack or notch. We thus have:


title: Fracture mechanics

text: where formula_53 is a function of the crack length and width of sheet given, for a sheet of finite width formula_56 containing a through-thickness crack of length formula_57, by:


title: Fracture mechanics

text: Irwin was the first to observe that if the size of the plastic zone around a crack is small compared to the size of the crack, the energy required to grow the crack will not be critically dependent on the state of stress (the plastic zone) at the crack tip. In other words, a purely elastic solution may be used to calculate the amount of energy available for fracture.


title: Fracture mechanics

text: The energy release rate for crack growth or "strain energy release rate" may then be calculated as the change in elastic strain energy per unit area of crack growth, i.e.,


title: Fracture mechanics

text: where "U" is the elastic energy of the system and "a" is the crack length. Either the load "P" or the displacement "u" are constant while evaluating the above expressions.


title: Fracture mechanics

text: Irwin showed that for a mode I crack (opening mode) the strain energy release rate and the stress intensity factor are related by:


title: Fracture mechanics

text: where "E" is the Young's modulus, "ν" is Poisson's ratio, and "K" is the stress intensity factor in mode I. Irwin also showed that the strain energy release rate of a planar crack in a linear elastic body can be expressed in terms of the mode I, mode II (sliding mode), and mode III (tearing mode) stress intensity factors for the most general loading conditions.


title: Fracture mechanics

text: Next, Irwin adopted the additional assumption that the size and shape of the energy dissipation zone remains approximately constant during brittle fracture. This assumption suggests that the energy needed to create a unit fracture surface is a constant that depends only on the material. This new material property was given the name "fracture toughness" and designated "G". Today, it is the critical stress intensity factor "K", found in the plane strain condition, which is accepted as the defining property in linear elastic fracture mechanics.


title: Fracture mechanics

text: In theory the stress at the crack tip where the radius is nearly zero, would tend to infinity. This would be considered a stress singularity, which is not possible in real-world applications. For this reason, in numerical studies in the field of fracture mechanics, it is often appropriate to represent cracks as round tipped notches, with a geometry dependent region of stress concentration replacing the crack-tip singularity. In actuality, the stress concentration at the tip of a crack within real materials has been found to have a finite value but larger than the nominal stress applied to the specimen.


title: Fracture mechanics

text: Nevertheless, there must be some sort of mechanism or property of the material that prevents such a crack from propagating spontaneously. The assumption is, the plastic deformation at the crack tip effectively blunts the crack tip. This deformation depends primarily on the applied stress in the applicable direction (in most cases, this is the y-direction of a regular Cartesian coordinate system), the crack length, and the geometry of the specimen. To estimate how this plastic deformation zone extended from the crack tip, Irwin equated the yield strength of the material to the far-field stresses of the y-direction along the crack (x direction) and solved for the effective radius. From this relationship, and assuming that the crack is loaded to the critical stress intensity factor, Irwin developed the following expression for the idealized radius of the zone of plastic deformation at the crack tip:


title: Fracture mechanics

text: Models of ideal materials have shown that this zone of plasticity is centered at the crack tip. This equation gives the approximate ideal radius of the plastic zone deformation beyond the crack tip, which is useful to many structural scientists because it gives a good estimate of how the material behaves when subjected to stress. In the above equation, the parameters of the stress intensity factor and indicator of material toughness, formula_62, and the yield stress, formula_63, are of importance because they illustrate many things about the material and its properties, as well as about the plastic zone size. For example, if formula_43 is high, then it can be deduced that the material is tough, and if formula_63 is low, one knows that the material is more ductile. The ratio of these two parameters is important to the radius of the plastic zone. For instance, if formula_63 is small, then the squared ratio of formula_62 to formula_63 is large, which results in a larger plastic radius. This implies that the material can plastically deform, and, therefore, is tough. This estimate of the size of the plastic zone beyond the crack tip can then be used to more accurately analyze how a material will behave in the presence of a crack.


title: Fracture mechanics

text: The same process as described above for a single event loading also applies and to cyclic loading. If a crack is present in a specimen that undergoes cyclic loading, the specimen will plastically deform at the crack tip and delay the crack growth. In the event of an overload or excursion, this model changes slightly to accommodate the sudden increase in stress from that which the material previously experienced. At a sufficiently high load (overload), the crack grows out of the plastic zone that contained it and leaves behind the pocket of the original plastic deformation. Now, assuming that the overload stress is not sufficiently high as to completely fracture the specimen, the crack will undergo further plastic deformation around the new crack tip, enlarging the zone of residual plastic stresses. This process further toughens and prolongs the life of the material because the new plastic zone is larger than what it would be under the usual stress conditions. This allows the material to undergo more cycles of loading. This idea can be illustrated further by the graph of Aluminum with a center crack undergoing overloading events.


title: Fracture mechanics

text: But a problem arose for the NRL researchers because naval materials, e.g., ship-plate steel, are not perfectly elastic but undergo significant plastic deformation at the tip of a crack. One basic assumption in Irwin's linear elastic fracture mechanics is small scale yielding, the condition that the size of the plastic zone is small compared to the crack length. However, this assumption is quite restrictive for certain types of failure in structural steels though such steels can be prone to brittle fracture, which has led to a number of catastrophic failures.


title: Fracture mechanics

text: Linear-elastic fracture mechanics is of limited practical use for structural steels and Fracture toughness testing can be expensive.


title: Fracture mechanics

text: Most engineering materials show some nonlinear elastic and inelastic behavior under operating conditions that involve large loads. In such materials the assumptions of linear elastic fracture mechanics may not hold, that is,


title: Fracture mechanics

text: Therefore, a more general theory of crack growth is needed for elastic-plastic materials that can account for:


title: Fracture mechanics

text: Historically, the first parameter for the determination of fracture toughness in the elasto-plastic region was the crack tip opening displacement (CTOD) or "opening at the apex of the crack" indicated. This parameter was determined by Wells during the studies of structural steels, which due to the high toughness could not be characterized with the linear elastic fracture mechanics model. He noted that, before the fracture happened, the walls of the crack were leaving and that the crack tip, after fracture, ranged from acute to rounded off due to plastic deformation. In addition, the rounding of the crack tip was more pronounced in steels with superior toughness.


title: Fracture mechanics

text: There are a number of alternative definitions of CTOD. In the two most common definitions, CTOD is the displacement at the original crack tip and the 90 degree intercept. The latter definition was suggested by Rice and is commonly used to infer CTOD in finite element models of such. Note that these two definitions are equivalent if the crack tip blunts in a semicircle.


title: Fracture mechanics

text: Most laboratory measurements of CTOD have been made on edge-cracked specimens loaded in three-point bending. Early experiments used a flat paddle-shaped gage that was inserted into the crack; as the crack opened, the paddle gage rotated, and an electronic signal was sent to an x-y plotter. This method was inaccurate, however, because it was difficult to reach the crack tip with the paddle gage. Today, the displacement V at the crack mouth is measured, and the CTOD is inferred by assuming the specimen halves are rigid and rotate about a hinge point (the crack tip).


title: Fracture mechanics

text: An early attempt in the direction of elastic-plastic fracture mechanics was Irwin's crack extension resistance curve, Crack growth resistance curve or R-curve. This curve acknowledges the fact that the resistance to fracture increases with growing crack size in elastic-plastic materials. The R-curve is a plot of the total energy dissipation rate as a function of the crack size and can be used to examine the processes of slow stable crack growth and unstable fracture. However, the R-curve was not widely used in applications until the early 1970s. The main reasons appear to be that the R-curve depends on the geometry of the specimen and the crack driving force may be difficult to calculate.


title: Fracture mechanics

text: In the mid-1960s James R. Rice (then at Brown University) and G. P. Cherepanov independently developed a new toughness measure to describe the case where there is sufficient crack-tip deformation that the part no longer obeys the linear-elastic approximation. Rice's analysis, which assumes non-linear elastic (or monotonic deformation theory plastic) deformation ahead of the crack tip, is designated the J-integral. This analysis is limited to situations where plastic deformation at the crack tip does not extend to the furthest edge of the loaded part. It also demands that the assumed non-linear elastic behavior of the material is a reasonable approximation in shape and magnitude to the real material's load response. The elastic-plastic failure parameter is designated J and is conventionally converted to K using the equation below. Also note that the J integral approach reduces to the Griffith theory for linear-elastic behavior.


title: Fracture mechanics

text: Since engineers became accustomed to using "K" to characterise fracture toughness, a relation has been used to reduce "J" to it:


title: Fracture mechanics

text: When a significant region around a crack tip has undergone plastic deformation, other approaches can be used to determine the possibility of further crack extension and the direction of crack growth and branching. A simple technique that is easily incorporated into numerical calculations is the "cohesive zone model" method which is based on concepts proposed independently by Barenblatt and Dugdale in the early 1960s. The relationship between the Dugdale-Barenblatt models and Griffith's theory was first discussed by Willis in 1967. The equivalence of the two approaches in the context of brittle fracture was shown by Rice in 1968.


title: Fracture mechanics

text: Let a material have a yield strength formula_63 and a fracture toughness in mode I formula_47. Based on fracture mechanics, the material will fail at stress formula_83. Based on plasticity, the material will yield when formula_84. These curves intersect when formula_85. This value of formula_3 is called as transition flaw size formula_87., and depends on the material properties of the structure. When the formula_88, the failure is governed by plastic yielding, and when formula_89 the failure is governed by fracture mechanics. The value of formula_90 for engineering alloys is 100 mm and for ceramics is 0.001 mm. If we assume that manufacturing processes can give rise to flaws in the order of micrometers, then, it can be seen that ceramics are more likely to fail by fracture, whereas engineering alloys would fail by plastic deformation.


title: 54th Academy Awards

text: The 54th Academy Awards ceremony, organized by the Academy of Motion Picture Arts and Sciences (AMPAS), honored films released in 1981 and took place on March 29, 1982, at the Dorothy Chandler Pavilion in Los Angeles beginning at 6:00 p.m. PST / 9:00 p.m. EST. During the ceremony, AMPAS presented Academy Awards (commonly referred to as Oscars) in 22 categories. The ceremony, televised in the United States by ABC, was produced by Howard W. Koch and directed by Marty Pasetta. Comedian and talk show host Johnny Carson hosted the show for the third consecutive time. One week earlier, in a ceremony held at The Beverly Hilton in Beverly Hills, California, on March 21, the Academy Scientific and Technical Awards were presented by hosts Lloyd Bridges and Fay Kanin.


title: 54th Academy Awards

text: "Chariots of Fire" won four awards, including Best Picture. Other winners included "Raiders of the Lost Ark" with five awards, "On Golden Pond" and "Reds" with three, "Arthur" with two, and "An American Werewolf in London", "Close Harmony", "Crac", "Genocide", "Mephisto", and "Violet" with one. The telecast garnered 46.2 million viewers in the United States.


title: 54th Academy Awards

text: The nominees for the 54th Academy Awards were announced on February 11, 1982, by Academy president Fay Kanin and actor Lloyd Bridges. "Reds" earned the most nominations with 12; "On Golden Pond" came in second with ten. The winners were announced at the awards ceremony on March 29. Best Director winner Warren Beatty became the first person to earn acting, directing, producing, and screenwriting nominations for the same film for the second time. He previously earned nominations in the same categories for 1978's "Heaven Can Wait". "On Golden Pond" was the fifth film to win both lead acting awards. Best Actress winner Katharine Hepburn became the first and only performer to win four competitive acting Oscars. Furthermore, the 48-year span between her first win for 1933's "Morning Glory" and her last win for "On Golden Pond", set the record for the longest span between first and last career Oscar nominations.


title: 54th Academy Awards

text: The award recognizes individuals whose humanitarian efforts have brought credit to the motion picture industry.


title: 54th Academy Awards

text: The award honors "creative producers whose bodies of work reflect a consistently high quality of motion picture production".


title: 54th Academy Awards

text: The following individuals, listed in order of appearance, presented awards or performed musical numbers.


title: 54th Academy Awards

text: In November 1981, the Academy hired film director, screenwriter, and producer Melvin Frank to produce the telecast for the first time. "The Academy is fortunate that Melvin Frank has agreed to make himself available for our show, said AMPAS President Fay Kanin in a press release announcing the selection. "He joins a distinguished list of producers who have consistently made the Academy Awards the entertainment highlight of the year." Two months later, it was announced that comedian and The Tonight Show host Johnny Carson would preside over emceeing duties for the 1982 ceremony. However, in February 1982, Howard W. Koch took over producing duties after Frank had been hospitalized for complications stemming from a virus. Koch stated that all artistic contributions made by Frank would remain during the production of the festivities.


title: 54th Academy Awards

text: Beginning with this ceremony, AMPAS introduced a new competitive award that would honor achievement in makeup. According to Academy executive administrator John Pavlik, the category would be presented if a special committee composed of makeup artists, hairstylists, cinematographers, and other related craftspeople determined that at least one film was deemed worthy of such awards. A maximum of seven films eligible for the award and determine how many nominations would compete in category. Prior to the introduction of this category, 1964's "7 Faces of Dr. Lao" and 1968's "Planet of the Apes" were given special honorary awards.


title: 54th Academy Awards

text: "St. Petersburg Times" film critic Thomas Sabulis wrote, "The Academy Awards show was a reasonably good television product. The acceptance speeches were thankfully brief and concise."


title: 54th Academy Awards

text: The American telecast on ABC drew in an average of 46.2 million people over the length of the entire ceremony, which was a 6% increase from the previous year's ceremony. The ceremony presentation won an award for Outstanding Art Direction for a Variety Program (Ray Klausen) at the 34th Primetime Emmys in September 1982.


title: Power engineering

text: Power engineering, also called power systems engineering, is a subfield of electrical engineering that deals with the generation, transmission, distribution, and utilization of electric power, and the electrical apparatus connected to such systems. Although much of the field is concerned with the problems of three-phase AC power – the standard for large-scale power transmission and distribution across the modern world – a significant fraction of the field is concerned with the conversion between AC and DC power and the development of specialized power systems such as those used in aircraft or for electric railway networks. Power engineering draws the majority of its theoretical base from electrical engineering.


title: Power engineering

text: Electricity became a subject of scientific interest in the late 17th century. Over the next two centuries a number of important discoveries were made including the incandescent light bulb and the voltaic pile. Probably the greatest discovery with respect to power engineering came from Michael Faraday who in 1831 discovered that a change in magnetic flux induces an electromotive force in a loop of wire—a principle known as electromagnetic induction that helps explain how generators and transformers work.


title: Power engineering

text: In 1881 two electricians built the world's first power station at Godalming in England. The station employed two waterwheels to produce an alternating current that was used to supply seven Siemens arc lamps at 250 volts and thirty-four incandescent lamps at 40 volts. However supply was intermittent and in 1882 Thomas Edison and his company, The Edison Electric Light Company, developed the first steam-powered electric power station on Pearl Street in New York City. The Pearl Street Station consisted of several generators and initially powered around 3,000 lamps for 59 customers. The power station used direct current and operated at a single voltage. Since the direct current power could not be easily transformed to the higher voltages necessary to minimise power loss during transmission, the possible distance between the generators and load was limited to around half-a-mile (800 m).


title: Power engineering

text: That same year in London Lucien Gaulard and John Dixon Gibbs demonstrated the first transformer suitable for use in a real power system. The practical value of Gaulard and Gibbs' transformer was demonstrated in 1884 at Turin where the transformer was used to light up forty kilometres (25 miles) of railway from a single alternating current generator. Despite the success of the system, the pair made some fundamental mistakes. Perhaps the most serious was connecting the primaries of the transformers in series so that switching one lamp on or off would affect other lamps further down the line. Following the demonstration George Westinghouse, an American entrepreneur, imported a number of the transformers along with a Siemens generator and set his engineers to experimenting with them in the hopes of improving them for use in a commercial power system.


title: Power engineering

text: One of Westinghouse's engineers, William Stanley, recognised the problem with connecting transformers in series as opposed to parallel and also realised that making the iron core of a transformer a fully enclosed loop would improve the voltage regulation of the secondary winding. Using this knowledge he built the world's first practical transformer based alternating current power system at Great Barrington, Massachusetts in 1886. In 1885 the Italian physicist and electrical engineer Galileo Ferraris demonstrated an induction motor and in 1887 and 1888 the Serbian-American engineer Nikola Tesla filed a range of patents related to power systems including one for a practical two-phase induction motor which Westinghouse licensed for his AC system.


title: Power engineering

text: By 1890 the power industry had flourished and power companies had built thousands of power systems (both direct and alternating current) in the United States and Europe – these networks were effectively dedicated to providing electric lighting. During this time a fierce rivalry in the US known as the "war of the currents" emerged between Edison and Westinghouse over which form of transmission (direct or alternating current) was superior. In 1891, Westinghouse installed the first major power system that was designed to drive an electric motor and not just provide electric lighting. The installation powered a synchronous motor at Telluride, Colorado with the motor being started by a Tesla induction motor. On the other side of the Atlantic, Oskar von Miller built a 20 kV 176 km three-phase transmission line from Lauffen am Neckar to Frankfurt am Main for the Electrical Engineering Exhibition in Frankfurt. In 1895, after a protracted decision-making process, the Adams No. 1 generating station at Niagara Falls began transmitting three-phase alternating current power to Buffalo at 11 kV. Following completion of the Niagara Falls project, new power systems increasingly chose alternating current as opposed to direct current for electrical transmission.


title: Power engineering

text: The generation of electricity was regarded as particularly important following the Bolshevik seizure of power. Lenin stated "Communism is Soviet power plus the electrification of the whole country." He was subsequently featured on many Soviet posters, stamps etc. presenting this view. The GOELRO plan was initiated in 1920 as the first Bolshevik experiment in industrial planning and in which Lenin became personally involved. Gleb Krzhizhanovsky was another key figure involved, having been involved in the construction of a power station in Moscow in 1910. He had also known Lenin since 1897 when they were both in the St. Petersburg chapter of the "Union of Struggle for the Liberation of the Working Class".


title: Power engineering

text: In 1936 the first commercial high-voltage direct current (HVDC) line using mercury-arc valves was built between Schenectady and Mechanicville, New York. HVDC had previously been achieved by installing direct current generators in series (a system known as the Thury system) although this suffered from serious reliability issues. In 1957 Siemens demonstrated the first solid-state rectifier (solid-state rectifiers are now the standard for HVDC systems) however it was not until the early 1970s that this technology was used in commercial power systems. In 1959 Westinghouse demonstrated the first circuit breaker that used SF as the interrupting medium. SF is a far superior dielectric to air and, in recent times, its use has been extended to produce far more compact switching equipment (known as switchgear) and transformers. Many important developments also came from extending innovations in the ICT field to the power engineering field. For example, the development of computers meant load flow studies could be run more efficiently allowing for much better planning of power systems. Advances in information technology and telecommunication also allowed for much better remote control of the power system's switchgear and generators.


title: Power engineering

text: Power Engineering deals with the generation, transmission, distribution and utilization of electricity as well as the design of a range of related devices. These include transformers, electric generators, electric motors and power electronics.


title: Power engineering

text: Power engineers may also work on systems that do not connect to the grid. These systems are called off-grid power systems and may be used in preference to on-grid systems for a variety of reasons. For example, in remote locations it may be cheaper for a mine to generate its own power rather than pay for connection to the grid and in most mobile applications connection to the grid is simply not practical.


title: Power engineering

text: Electricity generation covers the selection, design and construction of facilities that convert energy from primary forms to electric power.


title: Power engineering

text: Electric power transmission requires the engineering of high voltage transmission lines and substation facilities to interface to generation and distribution systems. High voltage direct current systems are one of the elements of an electric power grid.


title: Power engineering

text: Electric power distribution engineering covers those elements of a power system from a substation to the end customer.


title: Power engineering

text: Power system protection is the study of the ways an electrical power system can fail, and the methods to detect and mitigate for such failures.


title: Power engineering

text: In most projects, a power engineer must coordinate with many other disciplines such as civil and mechanical engineers, environmental experts, and legal and financial personnel. Major power system projects such as a large generating station may require scores of design professionals in addition to the power system engineers. At most levels of professional power system engineering practice, the engineer will require as much in the way of administrative and organizational skills as electrical engineering knowledge.


title: Power engineering

text: In both the UK and the US, professional societies had long existed for civil and mechanical engineers. The IEE was founded in the UK in 1871, and the AIEE in the United States in 1884. These societies contributed to the exchange of electrical knowledge and the development of electrical engineering education. On an international level, the International Electrotechnical Commission, which was founded in 1906, prepares standards for power engineering, with 20,000 electrotechnical experts from 172 countries developing global specifications based on consensus.


title: Sticky toffee pudding

text: Sticky toffee pudding, also known as sticky date pudding in Australia and New Zealand, is a British dessert consisting of a moist sponge cake, made with finely chopped dates (optional), covered in a toffee sauce and often served with a vanilla custard or vanilla ice-cream. It is considered a British classic by various culinary experts.


title: Sticky toffee pudding

text: A sticky toffee pudding has two essential components. The first is a moist sponge cake, containing finely chopped dates. The sponge is usually light and fluffy, closer to a muffin consistency rather than a heavier traditional British sponge, and is often lightly flavoured with nuts or spices such as cloves. The date component is, however, optional. The second key element is the toffee sauce, usually made from double cream and then different dark sugars, depending on recipe.


title: Sticky toffee pudding

text: A sticky toffee pudding is most commonly served with custard or vanilla ice cream, the vanilla flavour of these complimenting the richer flavours of the pudding. It may also be served with single cream.


title: Sticky toffee pudding

text: The origins of sticky toffee pudding are disputed. Owners of several pubs, including the Gait Inn in Millington, East Riding of Yorkshire (claimed to 1907) and the Udny Arms Hotel in Newburgh, Aberdeenshire (1960s), claim to have invented it.


title: Sticky toffee pudding

text: The pudding was popularised in the 1970s by Francis Coulson and Robert Lee, who developed and served it at the Sharrow Bay Country House Hotel in Cumbria The food critic Simon Hopkinson said Coulson told him he received the recipe from a Patricia Martin of Claughton in Lancashire, and that Martin had received this from Canadian air force officers who lodged at her hotel during the Second World War.


title: Sticky toffee pudding

text: In 1989, the owners of the Village Shop in Cartmel, Cumbria, developed a version of their sticky toffee pudding, which they had been making since 1984, that could be taken home and heated in the oven or microwave. Their dish became popular, and by the late 1990s was being sold in supermarkets across the UK.


title: Veerappan (2016 film)

text: Veerappan is a 2016 Indian Hindi-language biographical action crime film written and directed by Ram Gopal Varma. The film is based on the real-life Indian bandit Veerappan and the events leading to Operation Cocoon, a mission to capture and kill him. The film is a remake of the Kannada film "Killing Veerappan" (2016) starring Shiva Rajkumar. The film stars Sandeep Bharadwaj (who reprises his role from the original), Sachiin J Joshi, Lisa Ray and Usha Jadhav.


title: Veerappan (2016 film)

text: The film was released on May 27, 2016. "Veerappan" received positive reviews with critics praising narration, production design, direction and performances of Sandeep Bharadwaj, and Usha Jadav.


title: Veerappan (2016 film)

text: Koose Muniswamy Veerappan, during his teenage starts working as an assistant to his relative Sevi Gounder, a notorious poacher and sandalwood smuggler. His father and relatives, whose village lay in the forest area, were also known to be poachers and smugglers. Veerappan (Sandeep Bharadwaj), dominant in Sathyamangalam Forest in the states of Tamil Nadu and Karnataka,


title: Veerappan (2016 film)

text: defies the governments, and Indian Border security paramilitary forces, and maintain a small army. He is wanted for killing approximately 184 people, about half of whom were police officers, including senior police and forest officials. He was also wanted for poaching about 200 elephants and smuggling ivory worth US$2,600,000 and about 10,000 tonnes of sandalwood worth approximately US$22,000,000.


title: Veerappan (2016 film)

text: In 1991, Veerappan and his chief Intel Gandhi, behead IFS Officer P. Srinivas. Years later, Veerappan avenges the death of his close associate Gandhi by misleading Special Task Force (STF) personnel in their covert operation, through Gandhi's unnamed notorious informer. The covert mission led by T. Harikrishna S.P., and his informer S.I. Shakeel Ahmed to kill Veerappan fails miserably. Veerappan and his army brutally assassinate all the STF officers in the operation and snatch their arms.


title: Veerappan (2016 film)

text: The Tamil Nadu STF chief K. Vijay Kumar I.P.S. appoints his associate, an undercover I.P.S. spy in the Karnataka region, a master-strategist (Sachiin J Joshi), who puts in place the Operation Cocoon through a network of tribals, and informers, such as a Deputy spy, a woman STF spy and landlord (Lisa Ray), who befriends and rents out house to Muthulakshmi-the wife of Veerappan (Usha Jadhav). On the other hand, a team of loyal undercover cops led by Rambo Krishna, leave Palar base of STF, near M. M. Hills, from Kollegal of Karnataka along with a team of 41 members which includes police from two states, forest officials, forest watchers and informers. The team travels in two vehicles, of which one is a bus carrying most of the team members, and a jeep carrying K. Gopalakrishnan, the IPS officer. Veerappan's gang plants landmines on the road in more than 14 places to halt their approach, and during the Palar blast, K. Gopalakrishnan, standing on the footboard of the jeep, is thrown out, and suffer severe injuries, leaving the police to retaliate and ultimately prevent the snatching of arms.


title: Veerappan (2016 film)

text: After few failed attempts, including the one led by another undercover cop, disguised as a subordinate to Islamic underworld don - Kadaani, to negotiate an arms deal with Veerappan's gang, the STF team led by master-strategist, and an ex-spy turned timberyard owner-Kumar, finally succeed on 18 October 2004. On that day, Veerappan is escorted out of the forest by Kumar, who earlier infiltrates Veerappan's gang in disguise to negotiate another arms deal with Velupillai Prabhakaran. Subsequently, Veerappan and his men board an ambulance stationed at Papparapatti village in Dharmapuri district. Veerappan and his men are first warned and then asked to surrender, which was denied, and the men start firing at the STF personnel. The STF retaliate by firing grenades and gunfire, subsequently, Veerappan and his men are killed on the spot.


title: Veerappan (2016 film)

text: Pratik Vijay Redij is the production designer for the film. Following the success of Ram Gopal Varma's second docudrama, "Killing Veerappan", Varma met with Sachiin J Joshi, and emphasized his interest in developing an international biopic version in Hindi language with a new cast and crew. The biopic depicts the dramatic rise of Veerappan. In an Interview with "Indian Express" Varma stated that “Making "Veerappan" is not about glorifying a criminal, but it is to put a mirror to how he was allowed to happen in the first place”.


title: Veerappan (2016 film)

text: Upon its release, "Veerappan" received mixed reviews with critics praising narration, production design, direction and performances of Sandeep Bharadwaj, and Usha Jadav. In an Interview with "Indian Express" Varma stated that “Making "Veerappan" is not about glorifying a criminal, but it is to put a mirror to how he was allowed to happen in the first place”. The CBFC has cleared the film with a single cut. The "Times of India" gave the film 3.5/5 for its visual appeal, and 3/5 for direction.


title: Fume hood

text: A fume hood (sometimes called a fume cupboard or fume closet) is a type of local ventilation device that is designed to limit exposure to hazardous or toxic fumes, vapors or dusts.


title: Fume hood

text: A fume hood is typically a large piece of equipment enclosing five sides of a work area, the bottom of which is most commonly located at a standing work height.


title: Fume hood

text: Two main types exist, ducted and recirculating (ductless). The principle is the same for both types: air is drawn in from the front (open) side of the cabinet, and either expelled outside the building or made safe through filtration and fed back into the room. This is used to:


title: Fume hood

text: Secondary functions of these devices may include explosion protection, spill containment, and other functions necessary to the work being done within the device.


title: Fume hood

text: Fume hoods are generally set back against the walls and are often fitted with infills above, to cover up the exhaust ductwork. Because of their recessed shape they are generally poorly illuminated by general room lighting, so many have internal lights with vapor-proof covers. The front is a sash window, usually in glass, able to move up and down on a counterbalance mechanism. On educational versions, the sides and sometimes the back of the unit are also glass, so that several pupils can look into a fume hood at once. Low air flow alarm control panels are common, see below.


title: Fume hood

text: Fume hoods are generally available in 5 different widths; 1000 mm, 1200 mm, 1500 mm, 1800 mm and 2000 mm. The depth varies between 700 mm and 900 mm, and the height between 1900 mm and 2700 mm. These designs can accommodate from one to three operators.


title: Fume hood

text: For exceptionally hazardous materials, an enclosed glovebox may be used, which completely isolates the operator from all direct physical contact with the work material and tools. The enclosure may also be maintained at negative air pressure to ensure that nothing can escape via minute air leaks.


title: Fume hood

text: Most fume hoods are fitted with a mains-powered control panel. Typically, they perform one or more of the following functions:


title: Fume hood

text: Most fume hoods for industrial purposes are ducted. A large variety of ducted fume hoods exist. In most designs, conditioned (i.e. heated or cooled) air is drawn from the lab space into the fume hood and then dispersed via ducts into the outside atmosphere.


title: Fume hood

text: The fume hood is only one part of the lab ventilation system. Because recirculation of lab air to the rest of the facility is not permitted, air handling units serving the non-laboratory areas are kept segregated from the laboratory units. To improve indoor air quality, some laboratories also utilize single-pass air handling systems, wherein air that is heated or cooled is used only once prior to discharge. Many laboratories continue to use return air systems to the laboratory areas to minimize energy and running costs, while still providing adequate ventilation rates for acceptable working conditions. The fume hoods serve to evacuate hazardous levels of contaminant.


title: Fume hood

text: To reduce lab ventilation energy costs, variable air volume (VAV) systems are employed, which reduce the volume of the air exhausted as the fume hood sash is closed. This product is often enhanced by an automatic sash closing device, which will close the fume hood sash when the user leaves the fume hood face. The result is that the hoods are operating at the minimum exhaust volume whenever no one is actually working in front of them.


title: Fume hood

text: Since the typical fume hood in US climates uses 3.5 times as much energy as a home, the reduction or minimization of exhaust volume is strategic in reducing facility energy costs as well as minimizing the impact on the facility infrastructure and the environment. Particular attention must be paid to the exhaust discharge location, to reduce risks to public safety, and to avoid drawing exhaust air back into the building air supply system.


title: Fume hood

text: This method is outdated technology. The premise was to bring non-conditioned outside air directly in front of the hood so that this was the air exhausted to the outside. This method does not work well when the climate changes as it pours frigid or hot and humid air over the user making it very uncomfortable to work or affecting the procedure inside the hood. This system also uses additional ductwork which can be costly.


title: Fume hood

text: In a survey of 247 lab professionals conducted in 2010, "Lab Manager Magazine" found that approximately 43% of fume hoods are conventional CAV fume hoods.


title: Fume hood

text: Closing the sash on a non-bypass CAV hood will increase face velocity (inflow velocity or "pull"), which is a function of the total volume divided by the area of the sash opening. Thus, a conventional hood's performance (from a safety perspective) depends primarily on sash position, with safety increasing as the hood is drawn closed. To address this issue, many conventional CAV hoods specify a maximum height that the fume hood can be open in order to maintain safe airflow levels.


title: Fume hood

text: A major drawback of conventional CAV hoods is that when the sash is closed, velocities can increase to the point where they disturb instrumentation and delicate apparatuses, cool hot plates, slow reactions, and/or create turbulence that can force contaminants into the room.


title: Fume hood

text: Bypass CAV hoods (which are sometimes also referred to as conventional hoods) were developed to overcome the high velocity issues that affect conventional fume hoods. These hood allows air to be pulled through a "bypass" opening from above as the sash closes. The bypass is located so that as the user closes the sash, the bypass opening gets larger. The air going through the hood maintains a constant volume no matter where the sash is positioned and without changing fan speeds. As a result, the energy consumed by CAV fume hoods (or rather, the energy consumed by the building HVAC system and the energy consumed by the hood's exhaust fan) remains constant, or near constant, regardless of sash position.


title: Fume hood

text: "High-performance" or "low-flow" bypass CAV hoods are the newest type of bypass CAV hoods and typically display improved containment, safety, and energy conservation features. Low-flow/high performance CAV hoods generally have one or more of the following features: sash stops or horizontal-sliding sashes to limit the openings; sash position and airflow sensors that can control mechanical baffles; small fans to create an air-curtain barrier in the operator's breathing zone; refined aerodynamic designs and variable dual-baffle systems to maintain laminar (undisturbed, nonturbulent) flow through the hood. Although the initial cost of a high-performance hood is typically more than that of a conventional bypass hood, the improved containment and flow characteristics allow these hoods to operate at a face velocity as low as 60 fpm, which can translate into $2,000 per year or more in energy savings, depending on hood size and sash settings.


title: Fume hood

text: Reduced air volume hoods (a variation of low-flow/high performance hoods) incorporate a bypass block to partially close off the bypass, reducing the air volume and thus conserving energy. Usually, the block is combined with a sash stop to limit the height of the sash opening, ensuring a safe face velocity during normal operation while lowering the hood's air volume. By reducing the air volume, the RAV hood can operate with a smaller blower, which is another cost-saving advantage.


title: Fume hood

text: Since RAV hoods have restricted sash movement and reduced air volume, these hoods are less flexible in what they can be used for and can only be used for certain tasks. Another drawback to RAV hoods is that users can in theory override or disengage the sash stop. If this occurs, the face velocity could drop to an unsafe level. To counter this condition, operators must be trained never to override the sash stop while in use, and only to do so when loading or cleaning the hood.


title: Fume hood

text: VAV hoods, the newest generations of laboratory fume hoods, vary the volume of room air exhausted while maintaining the face velocity at a set level. Different VAV hoods change the exhaust volume using different methods, such as a damper or valve in the exhaust duct that opens and closes based on sash position, or a blower that changes speed to meet air-volume demands. Most VAV hoods integrate a modified bypass-block system that ensures adequate airflow at all sash positions. VAV hoods are connected electronically to the laboratory building's HVAC, so hood exhaust and room supply are balanced. In addition, VAV hoods feature monitors and/or alarms that warn the operator of unsafe hood-airflow conditions.


title: Fume hood

text: Although VAV hoods are much more complex than traditional constant-volume hoods, and correspondingly have higher initial costs, they can provide considerable energy savings by reducing the total volume of conditioned air exhausted from the laboratory. Since most hoods are operated the entire time a laboratory is open, this can quickly add up to significant cost savings. These savings are, however, completely contingent on user behavior: the less the hoods are open (both in terms of height and in terms of time), the greater the energy savings. For example, if the laboratory's ventilation system uses 100% once-through outside air and the value of conditioned air is assumed to be $7 per CFM per year (this value would increase with very hot, cold or humid climates), a 6-foot VAV fume hood at full open for experiment set up 10% of the time (2.4 hours per day), at 18 inch working opening 25% of the time (6 hours per day), and completely closed 65% of the time (15.6 hours per day) would save approximately $6,000 every year compared to a hood that is fully open 100% of the time.


title: Fume hood

text: Potential behavioral savings from VAV fume hoods are highest when fume hood density (number of fume hoods per square foot of lab space) is high. This is because fume hoods contribute to the achievement of lab spaces' required air exchange rates. Put another way, savings from closing fume hoods can only be achieved when fume hood exhaust rates are greater than the air exchange rate needed to achieve the required ventilation rate in the lab room. For example, in a lab room with a required air exchange rate of 2000 cubic feet per minute (CFM), if that room has just one fume hood which vents air at a rate of 1000 square feet per minute, then closing the sash on the fume hood will simply cause the lab room's air handler to increase from 1000 CFM to 2000 CFM, thus resulting in no net reduction in air exhaust rates, and thus no net reduction in energy consumption.


title: Fume hood

text: In a survey of 247 lab professionals conducted in 2010, "Lab Manager Magazine" found that approximately 12% of fume hoods are VAV fume hoods.


title: Fume hood

text: Canopy fume hoods, also called exhaust canopies, are similar to the range hoods found over stoves in commercial and some residential kitchens. They have only a canopy (and no enclosure and no sash) and are designed for venting non-toxic materials such as non-toxic smoke, steam, heat, and odors. In a survey of 247 lab professionals conducted in 2010, "Lab Manager Magazine" found that approximately 13% of fume hoods are ducted canopy fume hoods.


title: Fume hood

text: These units generally have a fan mounted on the top (soffit) of the hood, or beneath the worktop. Air is sucked through the front opening of the hood and through a filter, before passing through the fan and being fed back into the workplace. With a ductless fume hood it is essential that the filter medium be able to remove the particular hazardous or noxious material being used. As different filters are required for different materials, recirculating fume hoods should only be used when the hazard is well known and does not change. Ductless Hoods with the fan mounted below the work surface are not recommended as the majority of vapours rise and therefore the fan will have to work a lot harder (which may result in an increase in noise) to pull them downwards. Units with the fan mounted above the work surface have been proven to offer greater levels of safety.


title: Fume hood

text: Ductless fume hoods are sometimes not appropriate for research applications where the activity, and the materials used or generated, may change or be unknown. As a result of this and other drawbacks, some research organizations, including the University of Wisconsin, Milwaukee, Columbia University, Princeton University, the University of New Hampshire, and the University of Colorado, Boulder either discourage or prohibit the use of ductless fume hoods.


title: Fume hood

text: A benefit of ductless fume hoods is that they are mobile, easy to install since they require no ductwork, and can be plugged into a 120 volt or 240 volt outlet.


title: Fume hood

text: In a survey of 247 lab professionals conducted in 2010, "Lab Manager Magazine" found that approximately 22% of fume hoods are ductless fume hoods.


title: Fume hood

text: These units are typically constructed of polypropylene to resist the corrosive effects of acids at high concentrations. If hydrofluoric acid is being used in the hood, the hood's transparent sash should be constructed of polycarbonate which resists etching better than glass. Hood ductwork should be lined with polypropylene or coated with PTFE (Teflon).


title: Fume hood

text: Downflow fume hoods, also called downflow work stations, are typically ductless fume hoods designed to protect the user and the environment from hazardous vapors generated on the work surface. A downward air flow is generated and hazardous vapors are collected through slits in the work surface.


title: Fume hood

text: These units feature a waterwash system (scrubber - see below) in the ductwork. Because dense perchloric acid fumes settle and form explosive crystals, it is vital that the ductwork be cleaned internally with a series of sprays.


title: Fume hood

text: This fume hood is made with a coved stainless steel liner and coved integral stainless steel countertop that is reinforced to handle the weight of lead bricks or blocks.


title: Fume hood

text: This type of fume hood absorbs the fumes through a chamber filled with plastic shapes, which are doused with a scrubbing medium. The chemicals are washed into a sump, which is often filled with a neutralizing liquid. The fumes are then dispersed, or disposed of, in the conventional manner.


title: Fume hood

text: These fume hoods have an internal wash system that cleans the interior of the unit, to prevent a build-up of dangerous chemicals.


title: Fume hood

text: Because fume hoods constantly remove very large volumes of conditioned (heated or cooled) air from lab spaces, they are responsible for the consumption of large amounts of energy. Energy costs for a typical hood range from $4,600/year for moderate climates such as Los Angeles, to $9,300/year for extreme cooling climates such as Singapore. Fume hoods are a major factor in making laboratories four to five times more energy intensive than typical commercial buildings. The bulk of the energy that fume hoods are responsible for is the energy needed to heat and/or cool air delivered to the lab space. Additional electricity is consumed by fans in the HVAC system and fans in the fume hood exhaust system.


title: Fume hood

text: A number of universities run or have run programs to encourage lab users to reduce fume hood energy consumption by keeping VAV sashes closed as much as possible. For example, Harvard University's Chemistry & Chemical Biology Department ran a "Shut the sash" campaign, which resulted in a sustained ~30% reduction in fume hood exhaust rates. This translated into cost savings of approximately $180,000 per year, and a reduction in annual greenhouse gas emissions equivalent to 300 metric tons of carbon dioxide. Other institutions reporting programs to reduce energy consumption by fume hoods include Massachusetts Institute of Technology, North Carolina State University, University of British Columbia, University of California, Berkeley, University of California, Davis, University of California, Irvine, University of California, Los Angeles, University of California, Riverside, University of California, San Diego, University of California, Santa Barbara, University of Central Florida and University of Colorado, Boulder.


title: Fume hood

text: Newer person detection technology can sense the presence of a hood operator within a zone in front of a hood. Zone presence sensor signals allow ventilation valve controls to switch between normal and stand by modes. Coupled with laboratory space occupancy sensors these technologies can adjust ventilation to a dynamic performance objective.


title: Fume hood

text: The need for ventilation has been apparent from early days of chemical research and education. Some early approaches to the problem were adaptations of the conventional chimney. A hearth constructed by Thomas Jefferson in 1822–1826 at the University of Virginia was equipped with a sand bath and special flues to vent toxic gases.


title: Fume hood

text: In 1904 the newbuilt Chemical Faculty at the Technical University in Gdańsk was equipped with fume hoods made of wood and glass in auditoria, several lecture rooms, student laboratories and rooms for scientists. Sliding up and down front panel with glass protected from fumes and explosions. Each fume hood was illuminated, equipped with gas installation for heating and running water with a drain. Harmful and corrosive gaseous byproducts of reactions were actively removed using the natural draft of a fireplace chimney. This early design is still functioning after over 110 years.


title: Fume hood

text: The draft of a chimney was also used by Thomas Edison as what has been called the "first fume hood". The first known modern "fume cupboard" design with rising sashes was introduced at the University of Leeds in 1923.


title: Fume hood

text: Modern fume hoods are distinguished by methods of regulating air flow independently of combustion, improving efficiency and potentially removing volatile chemicals from exposure to flame. Fume hoods were originally manufactured from wood, but during the 1970s and 1980s epoxy powder-coated steel became the norm. During the 1990s, wood pulp derivatives treated with phenolic resin (plastic laminates and solid grade laminates) for chemical resistance and flame spread retardance started to become widely accepted.


title: Citadel of Qaitbay

text: The Citadel of Qaitbay (or the Fort of Qaitbay; ) is a 15th-century defensive fortress located on the Mediterranean sea coast, in Alexandria, Egypt. It was built from 1477 to 1479 AD (882–884 AH) by Sultan Al-Ashraf Sayf al-Din Qa'it Bay. The Citadel is situated on the eastern side of the northern tip of Pharos Island at the mouth of the Eastern Harbour.


title: Citadel of Qaitbay

text: The Qaitbay Citadel in Alexandria is considered one of the most important defensive strongholds, not only in Egypt, but also along the Mediterranean Sea coast. It formulated an important part of the fortification system of Alexandria in the 15th century AD.


title: Citadel of Qaitbay

text: The Citadel is situated at the entrance of the eastern harbour on the eastern point of the Pharos Island. It was erected on the exact site of the famous Lighthouse of Alexandria, which was one of the Seven Wonders of the Ancient World. The lighthouse continued to function until the time of the Arab conquest, then several disasters occurred and the shape of the lighthouse was changed to some extent, but it still continued to function. Restoration began in the period of Ahmed Ibn Tulun (about 880 AD). During the 11th century an earthquake occurred, causing damage to the octagonal part. The bottom survived, but it could only serve as a watchtower, and a small mosque was built on the top. In the 14th century there was a very destructive earthquake and the whole building was completely destroyed.


title: Citadel of Qaitbay

text: About 1480 AD, the Circassian Mameluke Sultan Al-Ashraf Qaitbay fortified the place as part of his coastal defensive edifices against the Turks, who were threatening Egypt at that time. He built the fortress and placed a mosque inside it. The Citadel continued to function during most of the Mameluke period, the Ottoman period and the Modern period, but after the British bombardment of Alexandria in 1882, it was kept out of the spotlight. It became neglected until the 20th century, when it was restored several times by the Egyptian Supreme Council of Antiquities.


title: Citadel of Qaitbay

text: The founder of the Citadel of Qaitbay is a Circassian Sultan named Al-Ashraf Abou Anasr Saif El-Din Qaitbay El-Jerkasy Al-Zahiry (1468–1496 AD) who was born about 1423 AD (826 AH). He was a Mamluke who had come to Egypt as a young man, less than 20 years old. Bought by Al-Ashraf Bersbay, he remained among his attendants until Al-Ashraf Bersbay died. Then the Sultan Jaqmaq bought Qaitbay, and later gave him his freedom. Qaitbay then went on to occupy various posts. He became the Chief of the Army (Atabec Al-Askar) during the rule of the Sultan Timurbugha. When the Sultan was dethroned, Qaitbay was appointed as a Sultan who was titled Almalek Al-Ashraf on Monday 26th Ragab, 872 AH (1468 AD). He was one of the most important and prominent Mameluke Sultans, ruling for about 29 years. He was a brave king, who tried to initiate a new era with the Ottomans by exchanging embassies and gifts. He was fond of travel and made many prominent journeys.


title: Citadel of Qaitbay

text: Qaitbay was so fond of art and architecture that he created an important post among the administrative system of the state; it was the Edifices Mason (Shady Al-Ama'er). He built many beneficial constructions in Mecca, Medina, and Jerusalem. In Egypt there are about 70 renovated edifices attributed to him, among them are mosques, Madrasas, agencies, Fountain houses (Sabils), Kuttabs, houses, military edifices like the Citadels in Alexandria and Rosetta (Nowadays the city of Rashid). These Citadels were built to protect the north of Egypt, mainly against the Ottomans, whose power was increasing in the Mediterranean.


title: Citadel of Qaitbay

text: Qagmas Al-Eshaqy, The Edifices Mason, was the architect of the Citadel. Before his arrival in Egypt he was a Mameluke of Djakmaq in Syria. During the rule of Qaitbay he became the edifices mason, and then the Viceroy of Alexandria. He was appointed governor of Syria (Damascus), built a Mosque outside the gate of Rashid (Bab Rashid) as well as a Cenotaph and a Khan. He also renovated the Mosque of El-Sawary outside the gate of Sadrah (Bab Sadrah).


title: Citadel of Qaitbay

text: Qagmas was intelligent and modest, as well as the overseer of many constructions during the time of Qaitbay. In 882 AH (1477 AD) the Sultan Qaitbay visited the site of the old lighthouse in Alexandria and ordered a fortress to be built on its foundations. The construction lasted about 2 years, and it is said that Qaitbay spent more than a hundred thousand gold dinars for the work on the Citadel.


title: Citadel of Qaitbay

text: Ibn Ayas mentioned that building of this fort started in the month of Rabi Alawal 882 H. He said that the Sultan Qaitbay travelled to Alexandria, accompanied with some other Mameluke princes, to visit the site of the old lighthouse and during this visit he ordered the building of the Citadel.


title: Citadel of Qaitbay

text: In the month of Shaban 884 H, the Sultan Qaitbay travelled again to Alexandria when the construction was finished. He provided the fort with a brave legion of soldiers and various weapons. He also, as Ibn Ayas mentioned, dedicated several waqfs from which he financed the construction works as well as the salaries of the soldiers.


title: Citadel of Qaitbay

text: Throughout the Mameluke period, and due to its strategic location, the Citadel was well maintained by all the rulers who came after Qaitbay.


title: Citadel of Qaitbay

text: The Sultan Qansuh al-Ghuri gave the Citadel special attention. He visited it several times and increased the strength of the garrison, providing it with various weapons and equipment. It included a large prison made for the princes and the state-men whom the Sultan kept away from his favour for some reason. In the episodes of the year 960 H, Qansuh Al-Ghouri travelled to Alexandria with other princes.


title: Citadel of Qaitbay

text: El-Ghouri went to the Citadel of Qaitbay where he watched some manoeuvres and military training on the defensive weapons of the Citadel of that era. When he felt the approach of the Ottoman threat, he issued a military decree to forbid weapons to be taken out of the Citadel, he even announced that the death penalty would be the punishment to those who try to steal anything from the Citadel, and he ordered the inscription of this decree on a marble slate fixed to the door leading the court. It says: "" "In the name of God, the Most Gracious, the Most Merciful".


title: Citadel of Qaitbay

text: After the Ottoman Turks had conquered Egypt, even they cared for this unique Citadel. They used it for shelter, as they had done with the Citadel of Saladin in Cairo and the Citadels of Damietta, Rosetta, Al Borollos and El-Arish. They kept it in good condition and stationed it with infantry, artillery, a company of drummers and trumpeters, masons and carpenters.