title: High gain dielectric loaded exponentially tapered slot antenna array based on substrate integrated waveguide for V-band wireless communications

abstract: Abstract The conception of substrate integrated waveguide (SIW) technology and exponentially tapered slot (ETS) antenna are together used to design a high gain, and efficient planar dielectric loaded antenna for V-band wireless communications. SIW is used to feed the proposed antenna. To increase the gain of the antenna, a dielectric loaded portion is used in front of the antenna and works as a dielectric guiding structure. The dielectric loaded ETS antenna and compact SIW feed are fabricated on a single substrate, resulting in low cost and easy fabrication. The antenna with elliptical shaped dielectric loaded is fabricated using printed circuit board process. The measured gain of the single element antenna is 10.2 dB, while the radiation efficiency of 96.84% is obtained at 60 GHz. The Y-junction SIW power divider is used to form a 1 × 2 array structure. Measured gain of the 1 × 2 array antenna is 11.2 dB, while the measured radiation pattern and gain are almost constant within the wide bandwidth of the antenna.


title: Rainfall distribution around shrubs: Eco-geomorphic implications for arid hillslopes

abstract: A single shrub in a widely spaced shrubby area acts as a roughness element and, therefore, it can affect the distribution of the rainfall received on the ground surface surrounding it. This paper focuses on such rainfall distribution on arid hillslopes and its eco-geomorphic implications. Relatively simple methods were used to measure the rainfall around shrubs growing in a small basin that is associated with a prevailing wind direction during rain events. There was a trend toward significantly reduced rainfall onto bare soil areas located on the leeward side, compared with that on other bare soil areas along the hillslope. This may alert to another potential cause for patchiness in the hydrological response of arid hillslope systems.


title: A comparative study of optimally designed V-shaped magnet IPM synchronous motors

abstract: This paper conducts a comparative study on the predicted operating characteristics of a series of optimally designed concentrated-winding, V-shaped magnet Interior Permanent Magnet Synchronous Motors (IPMSMs). A local optimizer (nonlinear Simplex) and a global optimizer (Genetic Algorithm (GA)) are separately used to determine the dimensions of each optimized machine based on three distinctive Objective Functions (OFs) to (i) minimize the weight, (ii) minimize the electromagnetic losses, and (iii) minimize the losses and weight in a multi-objective solution. In order to conduct the experimental analysis and verify the predictions, a prototype of the optimized machine is fabricated.


title: A Minimalistic Approach to Sum-Product Network Learning for Real Applications

abstract: Sum-Product Networks (SPNs) are a class of expressive yet tractable hierarchical graphical models. LearnSPN is a structure learning algorithm for SPNs that uses hierarchical co-clustering to simultaneously identifying similar entities and similar features. The original LearnSPN algorithm assumes that all the variables are discrete and there is no missing data. We introduce a practical, simplified version of LearnSPN, MiniSPN, that runs faster and can handle missing data and heterogeneous features common in real applications. We demonstrate the performance of MiniSPN on standard benchmark datasets and on two datasets from Google's Knowledge Graph exhibiting high missingness rates and a mix of discrete and continuous features.


title: The relations between anger, coping with anger, and aggression, and the BIS/BAS system

abstract: In two studies, the relations between the experience and expression of anger and the Behavioral Inhibition System/Behavioral Approach System were investigated with self-report data. In a first study, our results replicated previous findings that trait anger relates positively to both BIS and BAS, and generalized these findings to a measure of trait anger based on contextual anger responses. In a second study, the relations between anger coping-styles, anger expression, and BIS/BAS were examined. It was hypothesized that coping with anger involves low activity of either BIS or BAS, resulting in the anger coping styles of anger-out and anger-in, respectively. Measures of anger-out were found to be positively related to a measure of BAS and negatively to a measure of BIS, whereas the opposite pattern of associations was obtained for anger-in. Furthermore, corresponding to an anger-out coping style, both physical and verbal aggression were found to be positively related to BAS, and negatively to BIS.


title: Exploring the Antecedents for Value Cocreation during Healthcare Service Provision

abstract: ABSTRACT: One of the challenges of providing healthcare services is to create and properly deliver value for consumers (i.e., patients). Patients (vs. physicians) have long obtained a passive role when receiving healthcare services (vs. providing services). However, the emerging Service-Dominant (S-D) Logic suggests that value is always co-created between the service provider and the service recipient. In line with this thinking, we argue that the value of healthcare services can be maximized when the physician and patient co-create that value together. While prior research on healthcare provider-patient relationships has examined related concepts to co-creation, research on co-creation in the healthcare context remains limited. Consequently, this research reviews concepts related to co-creation and determines whether they are in line with the tenets of the co-creation concept as proposed by the S-D Logic. Moreover, this research derives a conceptual model of the determinants of value co-creation in the context of healthcare provider-patient relationships. Finally, this research derives value functions that can be used to model co-creation in the healthcare service provision context.INTRODUCTIONThe emerging Service-Dominant (S-D) Logic in marketing argues that value is always co-created between the service provider and the service recipient (Vargo and Lusch 2004; Vargo, Maglio, and Akaka 2008). It suggests that consumers are endogenous to the value creation process, rather than targets of producer-created value, because they engage their unique knowledge and skills in social, dynamic, and interactive network relationships with firms and other stakeholders (Merz, He, and Vargo 2009). Thus, the S-D Logic embraces a process-oriented view to co-creation. Furthermore, the S-D Logic suggests that value is always uniquely and phenomenologically determined by the beneficiary (Vargo, Morgan, Akaka, and He 2009). As a result, the S-D Logic suggests that service providers need to aim at co-creating dynamic, social, and interactive service ecosystems together with their customers such that customers have the highest value-in-use and value-in-context perceptions (Merz et al. 2009).More recently, healthcare marketers have discussed the importance of applying the logic of co-creation to the healthcare context (Nambisan and Nambisan 2009). They argue that a more customer-centered approach to health services is needed due to an increasing focus on preventative health and patient self-care (McColl-Kennedy, Vargo, Dagger, Sweeney, and van Kasteren 2012; Roter, Hall, and Katz 1988). In addition, they argue that a more customercentered approach has many benefits for both the physician and the patient thereby further substantiating the importance of examining co-creation in the healthcare context in general and the healthcare provider-patient relationship context in particular (see also Jayawardhena and Foley 2000).Given this, it is not surprising that healthcare marketers have examined several concepts related to co-creation in the healthcare provider-patient relationship context, such as shared decision-making (e.g., Alden, Merz, and Akashi 2012), patient empowerment (e.g., Ouschan, Sweeney, and Johnson 2000), patient centeredness (e.g., Kinnersley, Stott, Peters, and Harvey 1999), patient involvement (e.g., Elwyn, Edwards, Kinnersely, and Grol 2000), patient participation (e.g., Guadoagnoli and Ward 1998), and patient autonomy (Hayashi, Hasui, Kitamura et al. 2000). This research has resulted in valuable insights. Most importantly, it has provided implicit evidence of the importance of the co-creation concept in the context of healthcare provider-patient relationships. However, it is unclear how these concepts are related to the cocreation concept. Furthermore, it is unclear what the determinants of the cocreation construct in the context of healthcare provider-patient relationships are. Finally, it is unclear how to model co-creation in the healthcare context. …


title: An online trajectory planning of struck ball with spin by table tennis robot

abstract: This paper is concerned with an online trajectory planning of a ping-pong ball struck by a racket of a robotic table tennis system, which can detect the coming ball and predict the striking point by the racket. The struck ball trajectory is determined by the rebound phenomenon on the racket and the flying motion with the air resistances, which are governed by physical models of a racket rebound model (RRM) and an aerodynamics model (ADM) respectively. Therefore, the racket motion for the desired struck ball trajectory is obtained by solving the ADM and the RRM sequentially backward in time. Especially, the two point boundary value problem (TPBVP) of the ADM has to be solved for a desired landing point in the opponent’s court. The finite difference method (FDM) for the TPBVP leads to a set of nonlinear simultaneous equations because of the ADM’s nonlinearity while the ball motion at the striking point as one of the boundaries is constrained by a condition which guarantees the existence of the solution of the RRM. Therefore, we propose an novel method where the set of simultaneous equations by the FDM is formulated as a time-varying one and it is linearized by replacing the timevarying terms to the time sequence of an analytical solution of an approximated ADM. This linearized equations are solved iteratively to improve the accuracy and to satisfy the constraint. The processing time and the accuracy are verified by numerical examples where the algorithm is coded by C++ Language.


title: Dynamic Functional Segregation and Integration in Human Brain Network During Complex Tasks

abstract: The analysis of the topology and organization of brain networks is known to greatly benefit from network measures in graph theory. However, to evaluate dynamic changes of brain functional connectivity, more sophisticated quantitative metrics characterizing temporal evolution of brain topological features are required. To simplify conversion of time-varying brain connectivity to a static graph representation is straightforward but the procedure loses temporal information that could be critical in understanding the brain functions. To extend the understandings of functional segregation and integration to a dynamic fashion, we recommend dynamic graph metrics to characterise temporal changes of topological features of brain networks. This study investigated functional segregation and integration of brain networks over time by dynamic graph metrics derived from EEG signals during an experimental protocol: performance of complex flight simulation tasks with multiple levels of difficulty. We modelled time-varying brain functional connectivity as multi-layer networks, in which each layer models brain connectivity at time window $t+\Delta t$ . Dynamic graph metrics were calculated to quantify temporal and topological properties of the network. Results show that brain networks under the performance of complex tasks reveal a dynamic small-world architecture with a number of frequently connected nodes or hubs, which supports the balance of information segregation and integration in brain over time. The results also show that greater cognitive workloads caused by more difficult tasks induced a more globally efficient but less clustered dynamic small-world functional network. Our study illustrates that task-related changes of functional brain network segregation and integration can be characterized by dynamic graph metrics.


title: Adult Content in Social Live Streaming Services: Characterizing Deviant Users and Relationships

abstract: Social Live Stream Services (SLSS) exploit a new level of social interaction. One of the main challenges in these services is how to detect and prevent deviant behaviors that violate community guidelines. In this work, we focus on adult content production and consumption in two widely used SLSS, namely Live.me and Loops Live, which have millions of users producing massive amounts of video content on a daily basis. We use a pre-trained deep learning model to identify broadcasters of adult content. Our results indicate that moderation systems in place are highly ineffective in suspending the accounts of such users. We create two large datasets by crawling the social graphs of these platforms, which we analyze to identify characterizing traits of adult content producers and consumers, and discover interesting patterns of relationships among them, evident in both networks.


Methods for Literature Reviews


title: Optimal sizing of a stand-alone hybrid energy system for water pumping in Sirte, Libya

abstract: In this paper, the size optimization of standalone Photovoltaic (PV)/Wind turbine hybrids system for water pumping in Sirte City, Libya are compared using HOMER Pro, HOMER Beta, and iHOGA softwares, specifically the cost of energy (COE), total net present cost (NPC), and size of the system. Various loads of water pumping for farm land are used. The optimal system suggested by iHOGA had the lowest NPC but highest COE, whereas HOMER Pro had the highest NPC but lowest COE. The results are supportive of using the renewable hybrid system for water pumping in Sirte, Libya.


title: A 77-GHz FMCW MIMO Radar Based on an SiGe Single-Chip Transceiver

abstract: This paper describes a novel frequency-modulated continuous-wave radar concept, where methods like nonuniform sparse antenna arrays and multiple-input multiple-output techniques are used to improve the angular resolution of the proposed system. To demonstrate the practical feasibility using standard production techniques, a prototype sensor using a novel four-channel single-chip radar transceiver in combination with differential patch antenna arrays was realized on off-the-shelf RF substrate. Furthermore, to demonstrate its practical applicability, the assembled system was tested in real world measurement scenarios in conjunction with the presented efficient signal processing algorithms.


title: Fusing laser point cloud and visual image at data level using a new reconstruction algorithm

abstract: Camera and LIDAR provide complementary information for robots to perceive the environment. In this paper, we present a system to fuse laser point cloud and visual information at the data level. Generally, cameras and LIDARs mounted on the unmanned ground vehicle have different viewports. Some objects which are visible to a LIDAR may become invisible to a camera. This will result in false depth assignment for the visual image and incorrect colorization for laser points. The inputs of the system are a color image and the corresponding LIDAR data. Coordinates of 3D laser points are first transformed into the camera coordinate system. Points outside the camera viewing volume are clipped. A new algorithm is proposed to recreate the underlying object surface of the potentially visible laser points as quadrangle mesh by exploiting the structure of the LIDAR as a priori. False edge is eliminated by constraining the angle between the laser scan trace and the radial direction of a given laser point, and quadrangles with non-consistent normal are pruned. In addition, the missing laser points are solved to avoid large holes in the reconstructed mesh. At last z-buffer algorithm is used to work for occlusion reasoning. Experimental results show that our algorithm outperforms the previous one. It can assign correct depth information to the visual image and provide the exact color to each laser point which is visible to the camera.


title: Deferred Acceptance Algorithms: History, Theory, Practice, and Open Questions

abstract: The deferred acceptance algorithm proposed by Gale and Shapley (1962) has had a profound influence on market design, both directly, by being adapted into practical matching mechanisms, and, indirectly, by raising new theoretical questions. Deferred acceptance algorithms are at the basis of a number of labor market clearinghouses around the world, and have recently been implemented in school choice systems in Boston and New York City. In addition, the study of markets that have failed in ways that can be fixed with centralized mechanisms has led to a deeper understanding of some of the tasks a marketplace needs to accomplish to perform well. In particular, marketplaces work well when they provide thickness to the market, help it deal with the congestion that thickness can bring, and make it safe for participants to act effectively on their preferences. Centralized clearinghouses organized around the deferred acceptance algorithm can have these properties, and this has sometimes allowed failed markets to be reorganized.


title: User Association for Load Balancing in Vehicular Networks: An Online Reinforcement Learning Approach

abstract: Recently, a number of technologies have been developed to promote vehicular networks. When vehicles are associated with the heterogeneous base stations (e.g., macrocells, picocells, and femtocells), one of the most important problems is to make load balancing among these base stations. Different from common mobile networks, data traffic in vehicular networks can be observed having regularities in the spatial–temporal dimension due to the periodicity of urban traffic flow. By taking advantage of this feature, we propose an online reinforcement learning approach, called ORLA. It is a distributed user association algorithm for network load balancing in vehicular networks. Based on the historical association experiences, ORLA can obtain a good association solution through learning from the dynamic vehicular environment continually. In the long run, the real-time feedback and the regular traffic association patterns both help ORLA cope with the dynamics of network well. In experiments, we use QiangSheng taxi movement to evaluate the performance of ORLA. Our experiments verify that ORLA has higher quality load balancing compared with other popular association methods.


title: Deriving HD maps for highly automated driving from vehicular probe data

abstract: High definition (HD) map data is a key feature to enable highly automated driving. With the advent of highly automated vehicles, car makers and map suppliers investigate new approaches to create and maintain HD maps by using on-board sensor data of series vehicles. While state-of-the-art-approaches focus on position and speed data analysis, the consideration of additional vehicle sensor data allows for novel approaches in the context of HD maps. By 2020, more than 30 million connected vehicles are expected to be sold per year, which will generate millions of terabytes of vehicular probe data. One of the major upcoming research issues is to find methods to exploit that probe data to generate and maintain HD maps. In this paper, we address how to develop such methods. We introduce a scalable infrastructure, which supports the ingestion, management and analysis of huge amounts of probe data. It supports an iterative process to develop, assess and tune methods for generating HD maps from probe data. We present a metric to assess methods regarding resulting map precision. As a proof of concept, we present an approach to derive road geometry of highways from location and sensor information.


title: Modeling and probabilistic reasoning of population evacuation during large-scale disaster

abstract: The Great East Japan Earthquake and the Fukushima nuclear accident cause large human population movements and evacuations. Understanding and predicting these movements is critical for planning effective humanitarian relief, disaster management, and long-term societal reconstruction. In this paper, we construct a large human mobility database that stores and manages GPS records from mobile devices used by approximately 1.6 million people throughout Japan from 1 August 2010 to 31 July 2011. By mining this enormous set of Auto-GPS mobile sensor data, the short-term and long-term evacuation behaviors for individuals throughout Japan during this disaster are able to be automatically discovered. To better understand and simulate human mobility during the disasters, we develop a probabilistic model that is able to be effectively trained by the discovered evacuations via machine learning technique. Based on our training model, population mobility in various cities impacted by the disasters throughout the country is able to be automatically simulated or predicted. On the basis of the whole database, developed model, and experimental results, it is easy for us to find some new features or population mobility patterns after the recent severe earthquake, tsunami and release of radioactivity in Japan, which are likely to play a vital role in future disaster relief and management worldwide.


title: Design, Analysis & Prototyping of a Semi-Automated Staircase-Climbing Rehabilitation Robot

abstract: In this paper, we describe the mechanical design, system overview, integration and control techniques associated with SKALA, a unique large-sized robot for carrying a person with physical disabilities, up and down staircases. As a regular wheelchair is unable to perform such a maneuver, the system functions as a non-conventional wheelchair with several intelligent features. We describe the unique mechanical design and the design choices associated with it. We showcase the embedded control architecture that allows for several different modes of teleoperation, all of which have been described in detail. We further investigate the architecture associated with the autonomous operation of the system.


title: Recovering traceability links between an API and its learning resources

abstract: Large frameworks and libraries require extensive developer learning resources, such as documentation and mailing lists, to be useful. Maintaining these learning resources is challenging partly because they are not explicitly linked to the frameworks' API, and changes in the API are not reflected in the learning resources. Automatically recovering traceability links between an API and learning resources is notoriously difficult due to the inherent ambiguity of unstructured natural language. Code elements mentioned in documents are rarely fully qualified, so readers need to understand the context in which a code element is mentioned. We propose a technique that identifies code-like terms in documents and links these terms to specific code elements in an API, such as methods. In an evaluation study with four open source systems, we found that our technique had an average recall and precision of 96%.


title: Fast best-effort search on graphs with multiple attributes

abstract: We address the problem of top-k search on graphs with multiple nodal attributes, which we call WAGs (short for Weighted Attribute Graphs). For example, a co-authorship network is a WAG, where each author is a node; each attribute corresponds to a particular topic (e.g., databases, data mining, and machine learning); and the amount of expertise in a particular topic is represented by a non-negative weight on that attribute. A typical search in this setting may be: find three coauthors (i.e., a triangle) where each author's expertise is greater than 50% in at least one topic area (i.e., attribute). We show that the problem of retrieving the optimal answer for graph search on WAGs is NP-complete. Moreover, we propose a fast and effective top-k graph search algorithm for WAGs. In an extensive experimental study, our proposed algorithm exhibits significant speed-up over competing approaches. On average, our proposed method achieves 7× faster query processing than the best competitor.


Graph Based Inverse Reinforcement Learning for Social Robot Navigation


A Python Specification of the Tkinter Textwidget


title: Advanced 0.13um smart power technology from 7V to 70V

abstract: This paper presents BCD process integrating 7V to 70V power devices on 0.13um CMOS platform for various power management applications. BJT, Zener diode and Schottky diode are available and non-volatile memory is embedded as well. LDMOS shows best-in-class specific Ron (R SP ) vs. BV DSS characteristics (i.e., 70V NMOS has R SP of 69mΩ-mm2 with BV DSS of 89V). Modular process scheme is used for flexibility to various requirements of applications.


title: Prediction Policy Problems

abstract: Most empirical policy work focuses on causal inference. We argue an important class of policy problems does not require causal inference but instead requires predictive inference. Solving these "prediction policy problems" requires more than simple regression techniques, since these are tuned to generating unbiased estimates of coefficients rather than minimizing prediction error. We argue that new developments in the field of "machine learning" are particularly useful for addressing these prediction problems. We use an example from health policy to illustrate the large potential social welfare gains from improved prediction.


title: Mixed-initiative co-creativity

abstract: Creating and designing with a machine: do we merely create together (co-create) or can a machine truly foster our creativity as human creators? When does such co-creation foster the co-creativity of both humans and machines? This paper investigates the simultaneous and/or iterative process of human and computational creators in a mixed-initiative fashion within the context of game design and attempts to draw from both theory and praxis towards answering the above questions. For this purpose, we first discuss the strong links between mixed-initiative co-creation and theories of human and computational creativity. We then introduce an assessment methodology of mixed-initiative co-creativity and, as a proof of concept, evaluate Sentient Sketchbook as a co-creation tool for game design. Core findings suggest that tools such as Sentient Sketchbook are not mere game authoring systems or mere enablers of creation but, instead, foster human creativity and realize mixed-initiative co-creativity.


title: Metaheuristics for efficient aircraft scheduling and re-routing at busy terminal control areas

abstract: Abstract Intelligent decision support systems for the real-time management of landing and take-off operations can be very effective in helping air traffic controllers to limit airport congestion at busy terminal control areas. The key optimization problem to be solved regards the assignment of airport resources to take-off and landing aircraft and the aircraft sequencing on them. The problem can be formulated as a mixed integer linear program. However, since this problem is strongly NP-hard, heuristic algorithms are typically adopted in practice to compute good quality solutions in a short computation time. This paper presents a number of algorithmic improvements implemented in the AGLIBRARY solver (a state-of-the-art optimization solver to deal with complex routing and scheduling problems) in order to improve the possibility of finding good quality solutions quickly. The proposed framework starts from a good initial solution for the aircraft scheduling problem with fixed routes (given the resources to be traversed by each aircraft), computed via a truncated branch-and-bound algorithm. A metaheuristic is then applied to improve the solution by re-routing some aircraft in the terminal control area. New metaheuristics, based on variable neighbourhood search, tabu search and hybrid schemes, are introduced. Computational experiments are performed on an Italian terminal control area under various types of disturbances, including multiple aircraft delays and a temporarily disrupted runway. The metaheuristics achieve solutions of remarkable quality, within a small computation time, compared with a commercial solver and with the previous versions of AGLIBRARY.


title: Distortion Models For Statistical Machine Translation

abstract: In this paper, we argue that n-gram language models are not sufficient to address word reordering required for Machine Translation. We propose a new distortion model that can be used with existing phrase-based SMT decoders to address those n-gram language model limitations. We present empirical results in Arabic to English Machine Translation that show statistically significant improvements when our proposed model is used. We also propose a novel metric to measure word order similarity (or difference) between any pair of languages based on word alignments.


title: Dermoscopic features of cutaneous leishmaniasis.

abstract: BACKGROUND ::: Previous studies have demonstrated that dermoscopy improves accuracy in diagnosing pigmented and non-pigmented tumors. Recently, there has been increasing evidence that dermoscopy can also be useful in the diagnosis of some skin infections. ::: ::: ::: OBJECTIVE ::: We sought to describe the dermoscopic features of cutaneous leishmaniasis. ::: ::: ::: METHOD ::: Dermoscopic examination (using the Derm Lite FOTO, 3Gen) of 144 CL lesions in 82 patients was performed. This study was conducted in the Imam Reza and Ghaem hospitals (Mashhad, Iran) from October 2010 to September 2011. ::: ::: ::: RESULTS ::: We observed the following dermoscopic features: generalized erythema (81.9%), white starbursts (60.4%), yellow hue (43.8%), yellow teardrop-like structures (41.7%), central ulcers (59%), hyperkeratosis (33.3%), and milia-like cysts (4.9%). We also observed vascular structures, including dotted vessels (61.1%), hairpin vessels (37.5%), linear irregular vessels (30.6%), comma-shaped vessels (29.9%), glomerular vessels (22.9%), arborizing telangiectasia (10.4%), and corkscrew vessels (4.2%). ::: ::: ::: LIMITATIONS ::: Biopsy and pathologic evaluation were not performed due to ethical considerations. ::: ::: ::: CONCLUSION ::: Important vascular patterns seen in melanocytic and non-melanocytic tumors were frequently observed in this infection. Dermoscopy may be a promising tool to predict the clinical course in cases of cutaneous leishmaniasis.


title: Food web complexity and chaotic population dynamics

abstract: In mathematical models, very simple communities consisting of three or more species frequently display chaotic dynamics which implies that long-term predictions of the population trajectories in time are impossible. Communities in the wild tend to be more complex, but evidence for chaotic dynamics from such communities is scarce. We used supercomputing power to test the hypothesis that chaotic dynamics become less frequent in model ecosystems when their complexity increases. We determined the dynamical stability of a universe of mathematical, nonlinear food web models with varying degrees of organizational complexity. We found that the frequency of unpredictable, chaotic dynamics increases with the number of trophic levels in a food web but decreases with the degree of complexity. Our results suggest that natural food webs possess architectural properties that may intrinsically lower the likelihood of chaotic community dynamics.


title: Actin nucleators in the nucleus: an emerging theme

abstract: Actin is an integral component of the cytoskeleton, forming a plethora of macromolecular structures that mediate various cellular functions. The formation of such structures relies on the ability of actin monomers to associate into polymers, and this process is regulated by actin nucleation factors. These factors use monomeric actin pools at specific cellular locations, thereby permitting rapid actin filament formation when required. It has now been established that actin is also present in the nucleus, where it is implicated in chromatin remodelling and the regulation of eukaryotic gene transcription. Notably, the presence of typical actin filaments in the nucleus has not been demonstrated directly. However, studies in recent years have provided evidence for the nuclear localisation of actin nucleation factors that promote cytoplasmic actin polymerisation. Their localisation to the nucleus suggests that these proteins mediate collaboration between the cytoskeleton and the nucleus, which might be dependent on their ability to promote actin polymerisation. The nature of this cooperation remains enigmatic and it will be important to elucidate the physiological relevance of the link between cytoskeletal actin networks and nuclear events. This Commentary explores the current evidence for the nuclear roles of actin nucleation factors. Furthermore, the implication of actin-associated proteins in relaying exogenous signals to the nucleus, particularly in response to cellular stress, will be considered.


title: Neural Document Embeddings for Intensive Care Patient Mortality Prediction

abstract: We present an automatic mortality prediction scheme based on the unstructured textual content of clinical notes. Proposing a convolutional document embedding approach, our empirical investigation using the MIMIC-III intensive care database shows significant performance gains compared to previously employed methods such as latent topic distributions or generic doc2vec embeddings. These improvements are especially pronounced for the difficult problem of post-discharge mortality prediction.


title: Partial migration: niche shift versus sexual maturation in fishes

abstract: Many fish populations have both resident and migratory individuals. Migrants usually grow larger and have higher reproductive potential but lower survival than resident conspecifics. The ‘decision’ about migration versus residence probably depends on the individual growth rate, or a physiological process like metabolic rate which is correlated with growth rate. Fish usually mature as their somatic growth levels off, where energetic costs of maintenance approach energetic intake. After maturation, growth also stagnates because of resource allocation to reproduction. Instead of maturation, however, fish may move to an alternative feeding habitat and their fitness may thereby be increased. When doing so, maturity is usually delayed, either to the new asymptotic length, or sooner, if that gives higher expected fitness. Females often dominate among migrants and males among residents. The reason is probably that females maximize their fitness by growing larger, because their reproductive success generally increases exponentially with body size. Males, on the other hand, may maximize fitness by alternative life histories, e.g. fighting versus sneaking, as in many salmonid species where small residents are the sneakers and large migrants the fighters. Partial migration appears to be partly developmental, depending on environmental conditions, and partly genetic, inherited as a quantitative trait influenced by a number of genes.


title: Distributed Ledger Technology: Blockchain Compared to Directed Acyclic Graph

abstract: Nowadays, blockchain is becoming a synonym for distributed ledger technology. However, blockchain is only one of the specializations in the field and is currently well-covered in existing literature, but mostly from a cryptographic point of view. Besides blockchain technology, a new paradigm is gaining momentum: directed acyclic graphs. The contribution presented in this paper is twofold. Firstly, the paper analyzes distributed ledger technology with an emphasis on the features relevant to distributed systems. Secondly, the paper analyses the usage of directed acyclic graph paradigm in the context of distributed ledgers, and compares it with the blockchain-based solutions. The two paradigms are compared using representative implementations: Bitcoin, Ethereum and Nano. We examine representative solutions in terms of the applied data structures for maintaining the ledger, consensus mechanisms, transaction confirmation confidence, ledger size, and scalability.


title: A study of the effect of different types of noise on the precision of supervised learning techniques

abstract: Machine learning techniques often have to deal with noisy data, which may affect the accuracy of the resulting data models. Therefore, effectively dealing with noise is a key aspect in supervised learning to obtain reliable models from data. Although several authors have studied the effect of noise for some particular learners, comparisons of its effect among different learners are lacking. In this paper, we address this issue by systematically comparing how different degrees of noise affect four supervised learners that belong to different paradigms. Specifically, we consider the Naive Bayes probabilistic classifier, the C4.5 decision tree, the IBk instance-based learner and the SMO support vector machine. We have selected four methods which enable us to contrast different learning paradigms, and which are considered to be four of the top ten algorithms in data mining (Yu et al. 2007). We test them on a collection of data sets that are perturbed with noise in the input attributes and noise in the output class. As an initial hypothesis, we assign the techniques to two groups, NB with C4.5 and IBk with SMO, based on their proposed sensitivity to noise, the first group being the least sensitive. The analysis enables us to extract key observations about the effect of different types and degrees of noise on these learning techniques. In general, we find that Naive Bayes appears as the most robust algorithm, and SMO the least, relative to the other two techniques. However, we find that the underlying empirical behavior of the techniques is more complex, and varies depending on the noise type and the specific data set being processed. In general, noise in the training data set is found to give the most difficulty to the learners.


title: Trend Filtering on Graphs

abstract: We introduce a family of adaptive estimators on graphs, based on penalizing the l1 norm of discrete graph differences. This generalizes the idea of trend filtering (Kim et al., 2009; Tibshirani, 2014), used for univariate nonparametric regression, to graphs. Analogous to the univariate case, graph trend filtering exhibits a level of local adaptivity unmatched by the usual l2-based graph smoothers. It is also defined by a convex minimization problem that is readily solved (e.g., by fast ADMM or Newton algorithms). We demonstrate the merits of graph trend filtering through both examples and theory.


title: FrameWorks 3D: Composition in the Third Dimension

abstract: Music composition on computer is a challenging task, involving a range of data types to be managed within a single software tool. A composition typically comprises a complex arrangement of material, with many internal relationships between data in different locations repetition, inversion, retrograde, reversal and more sophisticated transformations. The creation of such complex artefacts is labour intensive, and current systems typically place a significant cognitive burden on the composer in terms of maintaining a work as a coherent whole. FrameWorks 3D is an attempt to improve support for composition tasks within a Digital Audio Workstation (DAW) style environment via a novel three-dimensional (3D) user-interface. In addition to the standard paradigm of tracks, regions and tape recording analogy, FrameWorks displays hierarchical and transformational information in a single, fully navigable workspace. The implementation combines Java with Max/MSP to create a cross-platform, user-extensible package and will be used to assess the viability of such a tool and to develop the ideas further.


title: Compact Modified Wilkinson Power Divider With Physical Output Port Isolation

abstract: In this letter, a compact modified n-way Wilkinson power divider that allows physical isolation between output ports is presented. In the proposed power divider, the isolation impedances are positioned within quarter-wave transmission lines so that part of the lines can be used for interconnection and impedance transformation. Theoretical analysis is performed to derive the design equations of the proposed n-way power divider. Further, measurements show that the proposed power divider can reduce the insertion loss and circuit size when compared with a conventional Wilkinson power divider.


title: Adaptive differentiation of murine lymphocytes. I. Both T and B lymphocytes differentiating in F1 transplanted to parental chimeras manifest preferential cooperative activity for partner lymphocytes derived from the same parental type corresponding to the chimeric host

abstract: The concept of adaptive (selective) differentiation preducts that early differentiation of lymphocytes is conditioned by the environment in which such differentiation takes place. These processes appear to involve selection of lymphocytes according to their self-recognition between interacting lymphocytes is, at least in part, controlled by major histocompatibility complex-linked genes, then adaptive differentiation is also controlled by these genes. In these studies, we have tested the capacities of helper T lymphocytes and hapten-specific B lymphocytes primed in the environments of various combinations of bone marrow chimeras prepared between two parental strains (i.e. A/J and BALB/c) and their corresponding F1 hybrid (CAF1) to interact with primed B and T lymphocytes derived from conventional parent and F1 donors as well as all of the corresponding bone marrow chimera combinations. The results demonstrate clearly that (a) F1 transplanted to F1 chimeric lymphocytes display no restriction in terms of cooperative activity with all of the various partner cell combinations; (b) parent transplanted to F1 chimeric lymphocytes manifest effective cooperative activity only for partner cells from F) or parental donors corresponding to the haplotype of the original bone marrow donor, thereby behaving phenotypically just like conventional parental lymphocytes; and (c) F1 transplanted to parent chimeric lymphocytes display restricted haplotype preference in cooperating best with partner lymphocytes sharing the H-2 haplotype, either entirely or codomimantly, of the parental chimeric host. The implications of these findings for understanding certain controlling mechanisms for lymphocyte differentiation are discussed.


title: SemanticLock: An authentication method for mobile devices using semantically-linked images

abstract: We introduce SemanticLock, a single factor graphical authentication solution for mobile devices. SemanticLock uses a set of graphical images as password tokens that construct a semantically memorable story representing the user`s password. A familiar and quick action of dragging or dropping the images into their respective positions either in a \textit{continous flow} or in \textit{discrete} movements on the the touchscreen is what is required to use our solution. The authentication strength of the SemanticLock is based on the large number of possible semantic constructs derived from the positioning of the image tokens and the type of images selected. Semantic Lock has a high resistance to smudge attacks and it equally exhibits a higher level of memorability due to its graphical paradigm. In a three weeks user study with 21 participants comparing SemanticLock against other authentication systems, we discovered that SemanticLock outperformed the PIN and matched the PATTERN both on speed, memorability, user acceptance and usability. Furthermore, qualitative test also show that SemanticLock was rated more superior in like-ability. SemanticLock was also evaluated while participants walked unencumbered and walked encumbered carrying"everyday"items to analyze the effects of such activities on its usage.


title: Comparison of different classification techniques in predicting a university course final grade

abstract: In this paper, we subject the education evaluation to different classification techniques. Then, we compare their results. The main idea is to check the suitability of different classification techniques to be used as prediction tools. After that, we conduct a comparison of the obtained results. Some classification techniques show better suitability to respond to the given assignment than the others. At the end, we show the classification techniques, which can be used in these cases as a prediction tool.


title: Self-Supervised Sparse-to-Dense: Self-Supervised Depth Completion from LiDAR and Monocular Camera

abstract: Depth completion, the technique of estimating a dense depth image from sparse depth measurements, has a variety of applications in robotics and autonomous driving. However, depth completion faces 3 main challenges: the irregularly spaced pattern in the sparse depth input, the difficulty in handling multiple sensor modalities (when color images are available), as well as the lack of dense, pixel-level ground truth depth labels for training. In this work, we address all these challenges. Specifically, we develop a deep regression model to learn a direct mapping from sparse depth (and color images) input to dense depth prediction. We also propose a self-supervised training framework that requires only sequences of color and sparse depth images, without the need for dense depth labels. Our experiments demonstrate that the self-supervised framework outperforms a number of existing solutions trained with semi-dense annotations. Furthermore, when trained with semi-dense annotations, our network attains state-of-the-art accuracy and is the winning approach on the KITTI depth completion benchmark1 at the time of submission.1http://www.cvlibs.net/datasets/kitti/eval_depth.php?benchmark=depth_completion


title: ANVIL: Software-Based Protection Against Next-Generation Rowhammer Attacks

abstract: Ensuring the integrity and security of the memory system is critical. Recent studies have shown serious security concerns due to "rowhammer" attacks, where repeated accesses to a row of memory cause bit flips in adjacent rows. Recent work by Google's Project Zero has shown how to leverage rowhammer-induced bit-flips as the basis for security exploits that include malicious code injection and memory privilege escalation. Being an important security concern, industry has attempted to defend against rowhammer attacks. Deployed defenses employ two strategies: (1) doubling the system DRAM refresh rate and (2) restricting access to the CLFLUSH instruction that attackers use to bypass the cache to increase memory access frequency (i.e., the rate of rowhammering). We demonstrate that such defenses are inadequte: we implement rowhammer attacks that both avoid using the CLFLUSH instruction and cause bit flips with a doubled refresh rate. Our next-generation CLFLUSH-free rowhammer attack bypasses the cache by manipulating cache replacement state to allow frequent misses out of the last-level cache to DRAM rows of our choosing. To protect existing systems from more advanced rowhammer attacks, we develop a software-based defense, ANVIL, which thwarts all known rowhammer attacks on existing systems. ANVIL detects rowhammer attacks by tracking the locality of DRAM accesses using existing hardware performance counters. Our detector identifies the rows being frequently accessed (i.e., the aggressors), then selectively refreshes the nearby victim rows to prevent hammering. Experiments running on real hardware with the SPEC2006 benchmarks show that ANVIL has less than a 1% false positive rate and an average slowdown of 1%. ANVIL is low-cost and robust, and our experiments indicate that it is an effective approach for protecting existing and future systems from even advanced rowhammer attacks.


title: SlangSD: Building and Using a Sentiment Dictionary of Slang Words for Short-Text Sentiment Classification

abstract: Sentiment in social media is increasingly considered as an important resource for customer segmentation, market understanding, and tackling other socio-economic issues. However, sentiment in social media is difficult to measure since user-generated content is usually short and informal. Although many traditional sentiment analysis methods have been proposed, identifying slang sentiment words remains untackled. One of the reasons is that slang sentiment words are not available in existing dictionaries or sentiment lexicons. To this end, we propose to build the first sentiment dictionary of slang words to aid sentiment analysis of social media content. It is laborious and time-consuming to collect and label the sentiment polarity of a comprehensive list of slang words. We present an approach to leverage web resources to construct an extensive Slang Sentiment word Dictionary (SlangSD) that is easy to maintain and extend. SlangSD is publicly available for research purposes. We empirically show the advantages of using SlangSD, the newly-built slang sentiment word dictionary for sentiment classification, and provide examples demonstrating its ease of use with an existing sentiment system.


title: Image Compression using DCT upon Various Quantization

abstract: Discrete cosine transform (DCT) is a widely compression technique for converting an image into elementary frequency components. However, level of quality and compression is desired, scalar multiples of the JPEG standard quantization may be used. In this paper, DCT method was applied to compress image under various level of quality. Different quantization matrices of DCT’s coefficients are used to improve level of quality and compression ratio of JPEG image.


title: Möbius: A high performance transactional SSD with rich primitives

abstract: Providing transactional primitives of NAND flash based solid state disks (SSDs) have demonstrated a great potential for high performance transaction processing and relieving software complexity. Similar with software solutions like write-ahead logging (WAL) and shadow paging, transactional SSD has two parts of overhead which include: 1) write overhead under normal condition, and 2) recovery overhead after power failures. Prior transactional SSD designs utilize out-of-band (OOB) area in flash pages to store transaction information to reduce the first part of overhead. However, they are required to scan a large part of or even whole SSD after power failures to abort unfinished transactions. Another limitation of prior approaches is the unicity of transactional primitive they provided. In this paper, we propose a new transactional SSD design named Mobius. Mobius provides different types of transactional primitives to support static and dynamic transactions separately. Mobius flash translation layer (mFTL), which combines normal FTL with transaction processing by storing mapping and transaction information together in a physical flash page as atom inode. By amortizing the cost of transaction processing with FTL persistence, MFTL achieve high performance in normal condition and does not increase write amplification ratio. After power failures, Mobius can leverage atom inode to eliminate unnecessary scanning and recover quickly. We implemented a prototype of Mobius and compare it with other state-of-art transactional SSD designs. Experimental results show that Mobius can at most 67% outperform in transaction throughput (TPS) and 29 times outperform in recovery time while still have similar or even better write amphfication ratio comparing with prior hardware approaches.


title: An anonymous and untraceable password-based authentication scheme for session initiation protocol using smart cards

abstract: SUMMARY ::: ::: Recently, Zhang et al. proposed a password-based authenticated key agreement for session initiation protocol (Int J Commun Syst 2013, doi:10.1002/dac.2499). They claimed that their protocol is secure against known security attacks. However, in this paper, we indicate that the protocol by Zhang et al. is vulnerable to impersonation attack whereby an active adversary without knowing the user's password is able to introduce himself/herself as the user. In addition, we show that the protocol by Zhang et al. suffers from password changing attack. To overcome the weaknesses, we propose an improved authentication scheme for session initiation protocol. The rigorous analysis shows that our scheme achieves more security than the scheme by Zhang et al. Copyright © 2014 John Wiley & Sons, Ltd.


title: Effect of Facebook on the life of Medical University students

abstract: BACKGROUND ::: Facebook is a social networking service launched in February 2004, owned and operated by Facebook, Inc. As of June 2012, Facebook reports more than 1 billion active users. Objective of study was to evaluate the effect of Facebook on the social life, health and behavior of medical students. ::: ::: ::: METHODOLOGY ::: It was a cross sectional, observational and questionnaire based study conducted in Dow University OF Health Sciences during the period of January 2012 to November 2012. We attempted to interview all the participants who could be approached during the period of the study. Participants were MBBS students, while all students of other courses and programs were taken as exclusion criteria. Approximately 1050 questionnaires were distributed to participants. Fifty questionnaires were rejected due to incomplete answers, yielding 1000 usable responses for an approximate 95% response rate. Informed verbal consent was taken from each participant. Study was ethically approved by Institutional Review Board of Dow University of Health Sciences. All the data was entered and analyzed through SPSS 19. ::: ::: ::: RESULT ::: Out of total 1000 participants, males were 400 (40%) and females were 600 (60%). Participants were in the age group of 18-25 years with a mean age of 20.08 years. Most of the participants were using Facebook daily (N = 640, 64%) for around 3-4 hours (N = 401, 40.1%). Majority of them (N = 359, 35.9%) believed that they were equally active on Facebook and in real life while few believed their social life became worse after start using Facebook (N = 372, 37.2%). Most of the participants admitted that they were considered as shy in real world (N = 390, 39.0%) while in the world of Facebook they were considered as fun loving by their friends (N = 603, 60.3%). A large number of participants (N = 715, 75%) complained of mood swings. ::: ::: ::: CONCLUSION ::: Youngsters are willing to compromise their health, social life, studies for the sake of fun and entertainment or whatever satisfaction they get after using Facebook. What we observed in our study was that although majority of our subjects showed multiple signs of Facebook addiction, they don't realize it and if even they realize it they don't want to quit Facebook and even if they want to quit, they can't. Our observance concluded that majority of the users are highly addicted.


title: Tilting of posterior mandibular and maxillary implants for improved prosthesis support.

abstract: Rehabilitation of atrophied edentulous arches with endosseous implants in the posterior regions is often associated with anatomic problems such as jaw shape and location of the mental loop, mandibular canal, and maxillary sinuses. The purpose of this investigation was to modify the method for implant placement in the posterior part of the jaws to extend fixed implant-connected prostheses further distally, and to reduce the length of cantilevers in complete-arch prostheses without transpositioning the mandibular nerve or performing bone grafting in the maxilla. Forty-seven consecutive patients were treated with implants (25 patients/36 mandibular implants, 22 patients/30 maxillary implants) placed in tilted positions. They were followed a mean of 40 months (mandibles) and 53 months (maxillae). In the mandible, implants close to the mental foramina were tilted posteriorly approximately 25 to 35 degrees. In the maxilla, the posterior implants were placed close to and parallel with the sinus walls and were titled anteriorly/posteriorly approximately 30 to 35 degrees. Patients gained a mean distance of 6.5 mm of prosthesis support in the mandible and 9.3 mm in the maxilla, as a result of implant tilting. There were no implant failures in mandibles. The cumulative success rates in the maxilla at 5 years were 98% for tilted implants and 93% for non-tilted implants. Paresthesias of the mental nerve were observed on 4 sides during the first 2 to 3 weeks after implant placement. Analysis of the load distribution in one mandibular case showed no significant difference between tilted and the non-tilted implants, and the improved prosthesis support was confirmed. Satisfactory medium-term results concerning osseointegration and significant extension of prosthesis support show that the method can be recommended. This technique may allow for longer implants to be placed with improved bone anchorage.


title: High speed intra-body communication for personal health care

abstract: Intra-body communication (IBC) uses the conductive human body as the communication channel for data exchange. As the bio-sensor research is moving towards portable, wearable and implantable designs, IBC has significant potential applications for personal health care. Previous IBC research mainly focused on the electromagnetic (EM) IBC scheme, which resulted in low data rate (kbps). In this paper, we systematically studied the electric field (EF) IBC scheme, which enables 10Mbps data rate. The human body channel is thoroughly measured with attenuation, noise and distortion for the IBC application. High speed EF IBC links are tested with various modulation schemes. The minimum transmission power of different links is measured.


title: Musical anhedonia: Selective loss of emotional experience in listening to music

abstract: Recent case studies have suggested that emotion perception and emotional experience of music have independent cognitive processing. We report a patient who showed selective impairment of emotional experience only in listening to music, that is musical anhednia. A 71-year-old right-handed man developed an infarction in the right parietal lobe. He found himself unable to experience emotion in listening to music, even to which he had listened pleasantly before the illness. In neuropsychological assessments, his intellectual, memory, and constructional abilities were normal. Speech audiometry and recognition of environmental sounds were within normal limits. Neuromusicological assessments revealed no abnormality in the perception of elementary components of music, expression and emotion perception of music. Brain MRI identified the infarct lesion in the right inferior parietal lobule. These findings suggest that emotional experience of music could be selectively impaired without any disturbance of other music...


title: Sensorless Control of Induction Motors for Maximum Steady-State Torque and Fast Dynamics at Field Weakening

abstract: A method is described that fully utilizes both the maximum inverter voltage and current for steady-state torque production at field weakening. The control algorithm thus provides the maximum possible torque in the entire field weakening region. Dynamic requirements when operating at maximum voltage are met by creating a temporary voltage margin to enable a fast reaction of the current controller. The control algorithm is insensitive to changes of the machine parameters and to variations of the dc link voltage. The approach is based on a stator flux oriented scheme and permits operation without using a speed sensor.


title: A context-aware security architecture for emerging applications

abstract: We describe an approach to building security services for context-aware environments. Specifically, we focus on the design of security services that incorporate the use of security-relevant "context" to provide flexible access control and policy enforcement. We previously presented a generalized access control model that makes significant use of contextual information in policy definition. This document provides a concrete realization of such a model by presenting a system-level service architecture, as well as early implementation experience with the framework. Through our context-aware security services, our system architecture offers enhanced authentication services, more flexible access control and a security subsystem that can adapt itself based on current conditions in the environment. We discuss our architecture and implementation and show how it can be used to secure several sample applications.


title: Concept and application of LPM - a novel 3-D local position measurement system

abstract: Precise measurement of the local position of moveable targets in three dimensions is still considered to be a challenge. With the presented local position measurement technology, a novel system, consisting of small and lightweight measurement transponders and a number of fixed base stations, is introduced. The system is operating in the 5.8-GHz industrial-scientific-medical band and can handle up to 1000 measurements per second with accuracies down to a few centimeters. Mathematical evaluation is based on a mechanical equivalent circuit. Measurement results obtained with prototype boards demonstrate the feasibility of the proposed technology in a practical application at a race track.


title: Boosting Neural Machine Translation

abstract: Training efficiency is one of the main problems for Neural Machine Translation (NMT). Deep networks need for very large data as well as many training iterations to achieve state-of-the-art performance. This results in very high computation cost, slowing down research and industrialisation. In this paper, we propose to alleviate this problem with several training methods based on data boosting and bootstrap with no modifications to the neural network. It imitates the learning process of humans, which typically spend more time when learning "difficult" concepts than easier ones. We experiment on an English-French translation task showing accuracy improvements of up to 1.63 BLEU while saving 20% of training time.


title: A comparative study of sedation with dexmedetomidine or midazolam during spinal anesthesia

abstract: Background: Regional anesthesia offers several benefits over general anesthesia. But to the patient it may be stressful as they stay awake. Sedation during regional anesthesia plays an important role in reducing the stress and patient satisfaction. It gives anxiolysis and amnesia. In contrast to general anesthesia, verbal contact is possible whenever necessary. Dreaming might be considered as the purest form of sub consciousness and it is purely subjective. The incidence of intraoperative dreaming has not been reported by many. We designed this random prospective study to compare 2 different IV sedation protocols midazolam and Dexmedetomidine with respect to dreaming during sedation under regional anesthesia. ::: Methodology: One hundred and twenty adult patients were randomly assigned to 2 groups; Group M received IV inj midazolam and Group D received inj dexmedetomidine for sedation during spinal anesthesia. Sedation was assessed on Ramsay Sedation Score. Patients were interviewed on emergence and 30 minutes later to determine the incidence of dreams. Postoperatively, patient satisfaction with the sedation was also evaluated. The patients satisfaction was assessed using a scale from 1–100. Any untoward side effects were noted. Quantitative variables were compared between groups using Student’s t-test. Data for heart rate and mean arterial pressure were analyzed using a Friedman test. Chi-square analysis was used for comparison of categorical variables. ::: Results: 60 patients in each group were included in the final analysis. The incidence of dreaming was 16 % in the midazolam group and 3% in the dexmedetomidine group. High level of satisfaction with the sedation was observed in dexmedetomedine group. In this group 66% patients expressed sedation as excellent, 11%- good and 15% termed it as satisfactory. Midazolam was associated with decreased patient satisfaction; 26% patients termed it as excellent, 58% good and 15% satisfactory. ::: Conclusion: During spinal anesthesia with sedation, patients receiving midazolam had 5 times more dreaming than those receiving dexmedetomidine. However, dexmedetomidine provides better quality of sedation during regional anesthesia resulting in superior patient satisfaction than midazolam.


title: Joint image denoising using adaptive principal component analysis and self-similarity

abstract: The non-local means (NLM) has attracted enormous interest in image denoising problem in recent years. In this paper, we propose an efficient joint denoising algorithm based on adaptive principal component analysis (PCA) and self-similarity that improves the predictability of pixel intensities in reconstructed images. The proposed algorithm consists of two successive steps without iteration: the low-rank approximation based on parallel analysis, and the collaborative filtering. First, for a pixel and its nearest neighbors, the training samples in a local search window are selected to form the similar patch group by the block matching method. Next, it is factorized by singular value decomposition (SVD), whose left and right orthogonal basis denote local and non-local image features, respectively. The adaptive PCA automatically chooses the local signal subspace dimensionality of the noisy similar patch group in the SVD domain by the refined parallel analysis with Monte Carlo simulation. Thus, image features can be well preserved after dimensionality reduction, and simultaneously the noise is almost eliminated. Then, after the inverse SVD transform, the denoised image is reconstructed from the aggregate filtered patches by the weighted average method. Finally, the collaborative Wiener filtering is used to further remove the noise. The experimental results validate its generality and effectiveness in a wide range of the noisy images. The proposed algorithm not only produces very promising denoising results that outperforms the state-of-the-art methods in most cases, but also adapts to a variety of noise levels.


title: Silicon Photonic Transceiver Circuits With Microring Resonator Bias-Based Wavelength Stabilization in 65 nm CMOS

abstract: Photonic interconnects are a promising technology to meet the bandwidth demands of next-generation high-performance computing systems. This paper presents silicon photonic transceiver circuits for a microring resonator-based optical interconnect architecture in a 1 V standard 65 nm CMOS technology. The transmitter circuits incorporate high-swing ( $2{\rm V}_{{\rm pp}}$ and $4{\rm V}_{{\rm pp}})$ drivers with nonlinear pre-emphasis and automatic bias-based tuning for resonance wavelength stabilization. An optical forwarded-clock adaptive inverter-based transimpedance amplifier (TIA) receiver trades off power for varying link budgets by employing an on-die eye monitor and scaling the TIA supply for the required sensitivity. At 5 Gb/s operation, the $4{\rm V}_{{\rm pp}}$ transmitter achieves 12.7 dB extinction ratio with 4.04 mW power consumption, excluding laser power, when driving wire-bonded modulators designed in a 130 nm SOI process, while a 0.28 nm tuning range is obtained at 6.8 $\mu$ W/GHz efficiency with the bias-based tuning scheme implemented with the $2{\rm V}_{{\rm pp}}$ transmitter. When tested with a wire-bonded 150 fF p-i-n photodetector, the receiver achieves ${-}$ 9 dBm sensitivity at a ${\rm BER}=10^{-9}$ and consumes 2.2 mW at 8 Gb/s. Testing with an on-die test structure emulating a low-capacitance waveguide photodetector yields 17 $\mu$ A $_{{\rm pp}}$ sensitivity at 10 Gb/s and more than 40% power reduction with higher input current levels.


title: A two-dimensional heuristic decomposition approach to a three-dimensional multiple container loading problem

abstract: Efficient container loading has the potential to considerably reduce logistics and transportation costs. The container loading problem is computationally complex and, despite extensive academic effort, there remains room for algorithm improvement. Real-world problems are not always addressed satisfactorily primarily due to the large number of complex constraints and objectives. The problem addressed by this work is an unsolved multiple container loading problem introduced by Renault on the occasion of the 2014/2015 ESICUP challenge, organized by the EURO Special Interest Group on Cutting and Packing (ESICUP). Renault’s problem requires a large number of different items to be packed into containers of different types and sizes. Items must be grouped into stacks and respect the ‘this side up’ constraint. The primary objective is to minimize the volume of shipped containers. The smallest volume container may be left behind for the next shipment and is excluded from the main objective. Nevertheless, only a limited percentage of each product may be packed into this container. Additionally, a set of secondary objectives is considered. This work presents a decomposition approach embedded in a multi-phase heuristic for the problem. Feasible solutions are generated quickly, and subsequently improved by local search and post-processing procedures. Experiments revealed that the approach generates optimal solutions for two instances, in addition to good quality solutions for those remaining from the Renault set. The algorithmic contribution is, however, not restricted to the Renault instances. Experiments on less constrained container loading instances from the literature demonstrate the approach’s general applicability and competitiveness.


title: A 28GHz SiGe BiCMOS phase invariant VGA

abstract: The paper describes a technique to design a phase invariant variable gain amplifier (VGA). Variable gain is achieved by varying the bias current in a BJT, while the phase variation is minimized by designing a local feedback network such that the applied base to emitter voltage has a bias-dependent phase variation which compensates the inherent phase variation of the transconductance. Two differential 28GHz VGA variants based on these principles achieve −13dBm while consuming 35mW.


title: Adding Federated Identity Management to OpenStack

abstract: OpenStack is an open source cloud computing project that is enjoying wide. While many cloud deployments may be stand-alone, it is clear that secure federated community clouds, i.e., inter-clouds, are needed. Hence, there must be methods for federated identity management (FIM) that enable authentication and authorisation to be flexibly enforced across federated environments. Since there are many different FIM protocols either in use or in development today, this paper addresses the goal of adding protocol independent federated identity management to the OpenStack services. After giving a motivating example for secure cloud federation, and describing the conceptual design for protocol independent federated access, a detailed federated identity protocol sequence is presented. The paper then describes the implementation of the protocol independent system components, along with the incorporation of two different FIM protocols, namely SAML and Keystone proprietary. Finally performance measurements of the protocol independent components, and the two different protocols dependent components are presented, before the paper concludes with the current limitations.


title: Semi-Supervised Deep Learning Using Pseudo Labels for Hyperspectral Image Classification

abstract: Deep learning has gained popularity in a variety of computer vision tasks. Recently, it has also been successfully applied for hyperspectral image classification tasks. Training deep neural networks, such as a convolutional neural network for classification requires a large number of labeled samples. However, in remote sensing applications, we usually only have a small amount of labeled data for training because they are expensive to collect, although we still have abundant unlabeled data. In this paper, we propose semi-supervised deep learning for hyperspectral image classification-our approach uses limited labeled data and abundant unlabeled data to train a deep neural network. More specifically, we use deep convolutional recurrent neural networks (CRNN) for hyperspectral image classification by treating each hyperspectral pixel as a spectral sequence. In the proposed semi-supervised learning framework, the abundant unlabeled data are utilized with their pseudo labels (cluster labels). We propose to use all the training data together with their pseudo labels to pre-train a deep CRNN, and then fine-tune using the limited available labeled data. Further, to utilize spatial information in the hyperspectral images, we propose a constrained Dirichlet process mixture model (C-DPMM), a non-parametric Bayesian clustering algorithm, for semi-supervised clustering which includes pairwise must-link and cannot-link constraints-this produces high-quality pseudo-labels, resulting in improved initialization of the deep neural network. We also derived a variational inference model for the C-DPMM for efficient inference. Experimental results with real hyperspectral image data sets demonstrate that the proposed semi-supervised method outperforms state-of-the-art supervised and semi-supervised learning methods for hyperspectral classification.


title: Speech Graphs Provide a Quantitative Measure of Thought Disorder in Psychosis

abstract: BACKGROUND ::: Psychosis has various causes, including mania and schizophrenia. Since the differential diagnosis of psychosis is exclusively based on subjective assessments of oral interviews with patients, an objective quantification of the speech disturbances that characterize mania and schizophrenia is in order. In principle, such quantification could be achieved by the analysis of speech graphs. A graph represents a network with nodes connected by edges; in speech graphs, nodes correspond to words and edges correspond to semantic and grammatical relationships. ::: ::: ::: METHODOLOGY/PRINCIPAL FINDINGS ::: To quantify speech differences related to psychosis, interviews with schizophrenics, manics and normal subjects were recorded and represented as graphs. Manics scored significantly higher than schizophrenics in ten graph measures. Psychopathological symptoms such as logorrhea, poor speech, and flight of thoughts were grasped by the analysis even when verbosity differences were discounted. Binary classifiers based on speech graph measures sorted schizophrenics from manics with up to 93.8% of sensitivity and 93.7% of specificity. In contrast, sorting based on the scores of two standard psychiatric scales (BPRS and PANSS) reached only 62.5% of sensitivity and specificity. ::: ::: ::: CONCLUSIONS/SIGNIFICANCE ::: The results demonstrate that alterations of the thought process manifested in the speech of psychotic patients can be objectively measured using graph-theoretical tools, developed to capture specific features of the normal and dysfunctional flow of thought, such as divergence and recurrence. The quantitative analysis of speech graphs is not redundant with standard psychometric scales but rather complementary, as it yields a very accurate sorting of schizophrenics and manics. Overall, the results point to automated psychiatric diagnosis based not on what is said, but on how it is said.


title: Images of Eyes Enhance Investments in a Real-Life Public Good

abstract: A key issue in cooperation research is to determine the conditions under which individuals invest in a public good. Here, we tested whether cues of being watched increase investments in an anonymous public good situation in real life. We examined whether individuals would invest more by removing experimentally placed garbage (paper and plastic bottles) from bus stop benches in Geneva in the presence of images of eyes compared to controls (images of flowers). We provided separate bins for each of both types of garbage to investigate whether individuals would deposit more items into the appropriate bin in the presence of eyes. The treatment had no effect on the likelihood that individuals present at the bus stop would remove garbage. However, those individuals that engaged in garbage clearing, and were thus likely affected by the treatment, invested more time to do so in the presence of eyes. Images of eyes had a direct effect on behaviour, rather than merely enhancing attention towards a symbolic sign requesting removal of garbage. These findings show that simple images of eyes can trigger reputational effects that significantly enhance on non-monetary investments in anonymous public goods under real life conditions. We discuss our results in the light of previous findings and suggest that human social behaviour may often be shaped by relatively simple and potentially unconscious mechanisms instead of very complex cognitive capacities.


title: Real-time raster projection for web maps

abstract: The virtual globe is the default visualization for Digital Earth applications, but it can only show one half of the Earth. This article introduces user-adjustable, on-the-fly projection of georeferenced raster images for web mapping and web GIS applications. This technique allows users to center a map on arbitrary locations, while still seeing the entire Earth surface. Modern web mapping libraries can apply map projection transformations to vector data in the browser, but they do not currently support the projection of raster images at interactive frame rates. We use the cross-platform WebGL (Web Graphics Library) graphics pipeline for hardware-accelerated projection of raster data in web browsers. Two algorithmic techniques – inverse per-fragment projection, and combined forward per-triangle and inverse per-fragment projection – for georeferenced raster imagery are documented. The resulting raster maps combine the ease of use and flexibility of interactive virtual globes with the ability to show the enti...


title: Detectors and correctors: a theory of fault-tolerance components

abstract: Two primitive components, namely detectors and correctors, provide a basis for achieving the different types of fault tolerance properties required in computing systems. We develop the theory of these primitive tolerance components, characterizing precisely their role in achieving the different types of fault tolerance. Also, we illustrate how they can be used to formulate extant design methods and argue that they sometimes offer the potential for better designs than those obtained from extant methods.


title: Supplier selection using consistent fuzzy preference relations

abstract: Highlights? We proposed the consistent fuzzy preference relations (CFPR) method for vendor selection. ? The advantage of CFPR is computational simplicity and efficiency. ? The CFPR method guarantees the consistency of decision matrices. Supplier selection is usually involved a multi-criteria evaluation to assist decision-making. This study proposed a simple method for vendor selection. The proposed procedure utilizes the structure of criteria in analytic hierarchy process (AHP) model and employs consistent fuzzy preference relations (CFPR) to construct the decision matrices. The advantage of CFPR is computational simplicity and efficiency. The computation can be done by using an Excel spreadsheet or writing a simple computer program. Also, the CFPR method guarantees the consistency of decision matrices. In this paper, a step-by-step empirical example demonstrates the usage of this proposed method.


Prosodic and Linguistic Analysis of Semantic Fluency Data: A Window into Speech Production and Cognition


title: 5G: A Tutorial Overview of Standards, Trials, Challenges, Deployment, and Practice

abstract: There is considerable pressure to define the key requirements of 5G, develop 5G standards, and perform technology trials as quickly as possible. Normally, these activities are best done in series but there is a desire to complete these tasks in parallel so that commercial deployments of 5G can begin by 2020. 5G will not be an incremental improvement over its predecessors; it aims to be a revolutionary leap forward in terms of data rates, latency, massive connectivity, network reliability, and energy efficiency. These capabilities are targeted at realizing high-speed connectivity, the Internet of Things, augmented virtual reality, the tactile internet, and so on. The requirements of 5G are expected to be met by new spectrum in the microwave bands (3.3-4.2 GHz), and utilizing large bandwidths available in mm-wave bands, increasing spatial degrees of freedom via large antenna arrays and 3-D MIMO, network densification, and new waveforms that provide scalability and flexibility to meet the varying demands of 5G services. Unlike the one size fits all 4G core networks, the 5G core network must be flexible and adaptable and is expected to simultaneously provide optimized support for the diverse 5G use case categories. In this paper, we provide an overview of 5G research, standardization trials, and deployment challenges. Due to the enormous scope of 5G systems, it is necessary to provide some direction in a tutorial article, and in this overview, the focus is largely user centric, rather than device centric. In addition to surveying the state of play in the area, we identify leading technologies, evaluating their strengths and weaknesses, and outline the key challenges ahead, with research test beds delivering promising performance but pre-commercial trials lagging behind the desired 5G targets.


title: Abstract Features in Feature Modeling

abstract: A software product line is a set of program variants, typically generated from a common code base. Feature models describe variability in product lines by documenting features and their valid combinations. In product-line engineering, we need to reason about variability and program variants for many different tasks. For example, given a feature model, we might want to determine the number of all valid feature combinations or compute specific feature combinations for testing. However, we found that contemporary reasoning approaches can only reason about feature combinations, not about program variants, because they do not take abstract features into account. Abstract features are features used to structure a feature model that, however, do not have any impact at implementation level. Using existing feature-model reasoning mechanisms for program variants leads to incorrect results. Hence, although abstract features represent domain decisions that do not affect the generation of a program variant. We raise awareness of the problem of abstract features for different kinds of analyses on feature models. We argue that, in order to reason about program variants, abstract features should be made explicit in feature models. We present a technique based on propositional formulas that enables to reason about program variants rather than feature combinations. In practice, our technique can save effort that is caused by considering the same program variant multiple times, for example, in product-line testing.


title: Comparing the efficacy of low-dose vs high-dose cyclophosphamide regimen as induction therapy in the treatment of proliferative lupus nephritis: a single center study

abstract: Cyclophosphamide (CYC) has been the backbone immunosuppressive drug to achieve sustained remission in lupus nephritis (LN). The aim was to evaluate the efficacy and compare adverse effects of low and high dose intravenous CYC therapy in Indian patients with proliferative lupus nephritis. An open-label, parallel group, randomized controlled trial involving 75 patients with class III/IV LN was conducted after obtaining informed consent. The low dose group (n = 38) received 6 × 500 mg CYC fortnightly and high dose group (n = 37) received 6 × 750 mg/m2 CYC four-weekly followed by azathioprine. The primary outcome was complete/partial/no response at 52 weeks. The secondary outcomes were renal and non-renal flares and adverse events. Intention-to-treat analyses were performed. At 52 weeks, 27 (73%) in high dose group achieved complete/partial response (CR/PR) vs 19 (50%) in low dose (p = 0.04). CR was higher in the high dose vs low dose [24 (65%) vs 17 (44%)], although not statistically significant. Non-responders (NR) in the high dose group were also significantly lower 10 (27%) vs low dose 19 (50%) (p = 0.04). The change in the SLEDAI (Median, IQR) was also higher in the high dose 16 (7–20) in contrast to the low dose 10 (5.5–14) (p = 0.04). There was significant alopecia and CYC-induced leucopenia in high dose group. Renal relapses were significantly higher in the low dose group vs high dose [9 (24%) vs 1(3%), (p = 0.01)]. At 52 weeks, high dose CYC was more effective in inducing remission with decreased renal relapses in our population.


title: Two Tales of the World: Comparison of Widely Used World News Datasets GDELT and EventRegistry

abstract: In this work, we compare GDELT and Event Registry, which monitor news articles worldwide and provide big data to researchers regarding scale, news sources, and news geography. We found significant differences in scale and news sources, but surprisingly, we observed high similarity in news geography between the two datasets.


title: Stock market forecasting using hidden Markov model: a new approach

abstract: This paper presents hidden Markov models (HMM) approach for forecasting stock price for interrelated markets. We apply HMM to forecast some of the airlines stock. HMMs have been extensively used for pattern recognition and classification problems because of its proven suitability for modelling dynamic systems. However, using HMM for predicting future events is not straightforward. Here we use only one HMM that is trained on the past dataset of the chosen airlines. The trained HMM is used to search for the variable of interest behavioural data pattern from the past dataset. By interpolating the neighbouring values of these datasets forecasts are prepared. The results obtained using HMM are encouraging and HMM offers a new paradigm for stock market forecasting, an area that has been of much research interest lately.


title: A Reconfigurable Smart Sensor Interface for Industrial WSN in IoT Environment

abstract: A sensor interface device is essential for sensor data collection of industrial wireless sensor networks (WSN) in IoT environments. However, the current connect number, sampling rate, and signal types of sensors are generally restricted by the device. Meanwhile, in the Internet of Things (IoT) environment, each sensor connected to the device is required to write complicated and cumbersome data collection program code. In this paper, to solve these problems, a new method is proposed to design a reconfigurable smart sensor interface for industrial WSN in IoT environment, in which complex programmable logic device (CPLD) is adopted as the core controller. Thus, it can read data in parallel and in real time with high speed on multiple different sensor data. The standard of IEEE1451.2 intelligent sensor interface specification is adopted for this design. It comprehensively stipulates the smart sensor hardware and software design framework and relevant interface protocol to realize the intelligent acquisition for common sensors. A new solution is provided for the traditional sensor data acquisitions. The device is combined with the newest CPLD programmable technology and the standard of IEEE1451.2 intelligent sensor specification. Performance of the proposed system is verified and good effects are achieved in practical application of IoT to water environment monitoring.


title: Forensic investigation and analysis on digital evidence discovery through physical acquisition on smartphone

abstract: Cybercriminals are changing their strategies as users are less concerns on the smartphone and social networks security risks such as spams, that will threaten them as they are more dependent on the smartphone [1]. Thus, there's a need to perform the smartphone forensics analysis to retrieve and analysed the potentially great amounts and extremely valuable information on these devices. This paper investigates a wealth of personal and sensitive data by types of digital information as evidence and conducted forensic analysis on a popular smartphone Samsung Galaxy Note III. The standard approach applied to extract information from smartphone through physical acquisition and analysis using Cellebrite UFED. The results are presented to demonstrate the smartphone as a goldmine for investigators and as sources of digital evidence. Furthermore this research also presents the forensic tool and techniques for acquiring and examining digital evidence on this device. The evidence discovered include files, contacts, events of smartphone and social network data storage and location. The smartphone examined produced abundant user information and in total 98,127 artefacts were recovered. Performing the extraction and analysis of digital evidence over smartphone activities show the possibility of identifying potential suspects that could assist the forensic investigators in crime investigations.


title: An empirical investigation of mobile ticketing service adoption in public transportation

abstract: In this paper, we present results from a study of mobile ticketing service adoption in public transportation. The theoretical background of the study is based on technology adoption and trust theories, which are augmented with concepts of mobile use context and mobility. Our empirical findings from analyses of a survey data suggest that compatibility of the mobile ticketing service with consumer behavior is a major determinant of adoption. Mobility and contextual factors, including budget constraints, availability of other alternatives, and time pressure in the service use situation were also found to have a strong effect on the adoption decision. Our findings suggest that contextual and mobile service-specific features are important determinants of mobile service adoption and should thus be integrated into the traditional adoption models.


title: EMBROIDERED FULLY TEXTILE WEARABLE AN- TENNA FOR MEDICAL MONITORING APPLICATIONS

abstract: Telecommunication systems integrated within garments and wearable products are such methods by which medical devices are making an impact on enhancing healthcare provisions around the clock. These garments when fully developed will be capable of alerting and demanding attention if and when required along with minimizing hospital resources and labour. Furthermore, they can play a major role in preventative ailments, health irregularities and unforeseen heart or brain disorders in apparently healthy individuals. This work presents the feasibility of investigating an Ultra-WideBand (UWB) antenna made from fully textile materials that were used for the substrate as well as the conducting parts of the designed antenna. Simulated and measured results show that the proposed antenna design meets the requirements of wide working bandwidth and provides 17GHz bandwidth with compact size, washable and ∞exible materials. Results in terms of return loss, bandwidth, radiation pattern, current distribution as well as gain and e-ciency are presented to validate the usefulness of the current manuscript design. The work presented here has profound implications for future studies of a standalone suite that may one day help to provide wearer (patient) with such reliable and comfortable medical monitoring techniques.


title: Estimation of the Burned Area in Forest Fires Using Computational Intelligence Techniques

abstract: Abstract Forest fires have environmental impacts that create economic problems as well as ecological damage. Developing a means to predict the possible size of a fire shortly after it first breaks out has the potential to guide proper resource allocation for improved fire control and was the main motivation of this research. In this study, the burned areas resulting from possible forest fires were estimated using historical forest fire records which contained parameters like geographical conditions of the existing environment, date and time when the fire broke out, meteorological data such as temperature, humidity and wind speed, and the type and number of trees in a unit area. The data was from the Department of Forestry in Turkey and contained 7,920 forest fire records from 2000 and 2009. The output from the estimation methods implemented in this work predicted the size of the area lost due to the fire and the corresponding fire size, i.e. big, medium, or small fire. Some of the estimation methods investigated were Multilayer Perceptron (MLP), Radial Basis Function Networks (RBFN), Support Vector Machines (SVM) and fuzzy logic. The results of these estimates are presented and compared to similar studies in literature.


title: A comprehensive survey of energy-aware routing protocols in wireless body area sensor networks

abstract: Wireless body area sensor network is a special purpose wireless sensor network that, employing wireless sensor nodes in, on, or around the human body, makes it possible to measure biological parameters of a person for specific applications. One of the most fundamental concerns in wireless body sensor networks is accurate routing in order to send data promptly and properly, and therefore overcome some of the challenges. Routing protocols for such networks are affected by a large number of factors including energy, topology, temperature, posture, the radio range of sensors, and appropriate quality of service in sensor nodes. Since energy is highly important in wireless body area sensor networks, and increasing the network lifetime results in benefiting greatly from sensor capabilities, improving routing performance with reduced energy consumption presents a major challenge. This paper aims to study wireless body area sensor networks and the related routing methods. It also presents a thorough, comprehensive review of routing methods in wireless body area sensor networks from the perspective of energy. Furthermore, different routing methods affecting the parameter of energy will be classified and compared according to their advantages and disadvantages. In this paper, fundamental concepts of wireless body area sensor networks are provided, and then the advantages and disadvantages of these networks are investigated. Since one of the most fundamental issues in wireless body sensor networks is to perform routing so as to transmit data precisely and promptly, we discuss the same issue. As a result, we propose a classification of the available relevant literature with respect to the key challenge of energy in the routing process. With this end in view, all important papers published between 2000 and 2015 are classified under eight categories including `Mobility-Aware', `Thermal-Aware', `Restriction of Location and Number of Relays', `Link-aware', `Cluster- and Tree-Based', `Cross-Layer', `Opportunistic', and `Medium Access Control'. We, then, provide a full description of the statistical analysis of each category in relation to all papers, current hybrid protocols, and the type of simulators used in each paper. Next, we analyze the distribution of papers in each category during various years. Moreover, for each category, the advantages and disadvantages as well as the number of issued papers in different years are given. We also analyze the type of layer and deployment of mathematical models or algorithmic techniques in each category. Finally, after introducing certain important protocols for each category, the goals, advantages, and disadvantages of the protocols are discussed and compared with each other.


title: A Semantic Graph based Topic Model for Question Retrieval in Community Question Answering

abstract: Community Question Answering (CQA) services, such as Yahoo! Answers and WikiAnswers, have become popular with users as one of the central paradigms for satisfying users' information needs. The task of question retrieval aims to resolve one's query directly by finding the most relevant questions (together with their answers) from an archive of past questions. However, as the text of each question is short, there is usually a lexical gap between the queried question and the past questions. To alleviate this problem, we present a hybrid approach that blends several language modelling techniques for question retrieval, namely, the classic (query-likelihood) language model, the state-of-the-art translation-based language model, and our proposed semantics-based language model. The semantics of each candidate question is given by a probabilistic topic model which makes use of local and global semantic graphs for capturing the hidden interactions among entities (e.g., people, places, and concepts) in question-answer pairs. Experiments on two real-world datasets show that our approach can significantly outperform existing ones.


title: A circular polarizer designed with a dielectric septum loading

abstract: This paper presents a simple method to realize a circular polarizer by inserting a dielectric septum in the middle of the cylindrical waveguide. Since fixing slots are built to precisely locate the septum, dual-compensation slots are made in the orthogonal plane to balance the effects of the fixing slots. The measured axial ratio is smaller than 0.5 dB and the phase difference is flat in the frequency range from 60 to 62.25 GHz. In addition, the return losses are better than -13 dB for both E/sub x/ and E/sub y/ polarizations in the same frequency range. This design has the added advantage that poor phase differences resulting from fabrication error or an inaccurate dielectric constant can easily be improved by adjusting the length of the inserted dielectric septum.