Open Access. Powered by Scholars. Published by Universities.®

Computer Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

2017

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 2731 - 2760 of 2767

Full-Text Articles in Computer Sciences

An Area-Efficient And Wide-Range Digital Dll For Per-Pin Deskew Applications, Chingche Chung, Chienying Yu Jan 2017

An Area-Efficient And Wide-Range Digital Dll For Per-Pin Deskew Applications, Chingche Chung, Chienying Yu

Turkish Journal of Electrical Engineering and Computer Sciences

In this work, we present a 200 MHz to 1.6 GHz digital delay-locked loop (DLL) for per-pin deskew applications. The proposed phase shifters apply linear and scalable circuit architecture for the pin-to-pin delay mismatch of parallel I/O pins. The proposed phase detector with a detection window and the proposed consecutive phase decision method reduce the sensitivity to reference clock jitter. A test chip of the 0.042 mm$^{2}$ DLL and the 3-ps-adjustable-resolution phase shifters with a 0.0025 mm$^{2}$ per-channel area was implemented using a 90-nm CMOS process. Simulation results show that the phase error of the 90$^{\circ}$ phase shifter at 1.6 …


Offset-Free Adaptive Nonlinear Model Predictive Control With Disturbance Observer For Dc-Dc Buck Converters, Bahareh Vatankhah, Mohammad Farrokhi Jan 2017

Offset-Free Adaptive Nonlinear Model Predictive Control With Disturbance Observer For Dc-Dc Buck Converters, Bahareh Vatankhah, Mohammad Farrokhi

Turkish Journal of Electrical Engineering and Computer Sciences

The aim of this paper is to design a nonlinear model predictive control for DC-DC buck converters to track constant reference signals with zero steady-state error. The online trained neural network (NN) model is employed as the predictor and the steady-state error, which is called the offset, is studied in the presence of the changes in system parameters and the external disturbances. The stability of the closed-loop system is investigated using the Lyapunov direct theory. The proposed method can provide offset-free behavior in the presence of constant disturbances. For rejecting nonconstant disturbances, a nonlinear disturbance observer based on the NN …


Modified Control Of The Matrix Converter-Based Drive For Voltage Sag Impact Reduction, Gytis Petrauskas, Gytis Svinkunas Jan 2017

Modified Control Of The Matrix Converter-Based Drive For Voltage Sag Impact Reduction, Gytis Petrauskas, Gytis Svinkunas

Turkish Journal of Electrical Engineering and Computer Sciences

Faults in transmission and distribution networks often cause voltage sags. Direct matrix converter (DMC)-based drives are a new generation of electrical drives. Unlike the conventional two-stage diode supply-side inverter drive, the DMC drive has no direct current (DC) link capacitor and no capacitor charging-time delay before operation. The absence of a DC link makes the DMC-based drive more sensitive to voltage sags. The above-mentioned faults in transmission and distribution networks could degrade the DMC drive's performance and reliability. This paper investigates possible kinds and levels of voltage sags, dependency on network configuration, and the behavior of the DMC-based drive under …


Novel Control Strategy For Hybrid Renewable Energy-Based Standalone System, Rahul Sharma, Sathans Suhag Jan 2017

Novel Control Strategy For Hybrid Renewable Energy-Based Standalone System, Rahul Sharma, Sathans Suhag

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, novel control strategies are proposed for a hybrid renewable energy system under a standalone environment. The wind unit, solar unit, supercapacitor (SC), and battery are connected to a DC link through power converters. Control methods are proposed to mitigate the limitations of the standalone system. The control method is proposed to maintain constant DC link voltage under different conditions without using a dummy load (i.e. an electrolyzer). The SC and battery are used as storage devices. A novel control scheme is proposed to control storage devices where the SC is used to improve the slow response of …


An Efficient Ofdm-Based System With An Insufficient Cyclic Prefix Via A Novel Constellation Algorithm, Saeed Ghazi-Maghrebi Jan 2017

An Efficient Ofdm-Based System With An Insufficient Cyclic Prefix Via A Novel Constellation Algorithm, Saeed Ghazi-Maghrebi

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a new special triangular constellation scheme is introduced to replace the commonly used rectangular QAM constellation in orthogonal frequency division multiplexing (OFDM) modulation. We have shown that this new scheme has 3 major advantages with respect to the well-known QAM. The first advantage is its lower error probability performance, which results from better usage of the constellation space with longer minimum distances. The 2 other advantages are a lower peak to average power ratio (PAPR) and higher noise immunity. Both mathematical analysis and simulation results demonstrate that by applying standard channels in 2 cases, i.e. channels with …


Performance Enhancement Of A Dynamic Voltage Restorer, Latha Pappath Vasudevan, Valsalal Prasad Jan 2017

Performance Enhancement Of A Dynamic Voltage Restorer, Latha Pappath Vasudevan, Valsalal Prasad

Turkish Journal of Electrical Engineering and Computer Sciences

Custom power devices are widely employed to mitigate power quality issues affecting critical loads. The dynamic voltage restorer is one of the custom power devices designed to inject a voltage in series with line to present a pure sinusoidal voltage of the desired RMS value to the sensitive loads, if the supply side is affected by voltage disturbances. The design and implementation of a DVR with a quasi-impedance source inverter and variable structure control is discussed in this paper. The voltage boosting ability of a quasi-impedance (Z) source inverter is used here to improve the performance of the DVR with …


Planar Array Of Right-Angled Isosceles Triangular Microstrip Antenna Using Koch And Meander Lines For The Internet Of Things, Manisha Gupta, Vinita Mathur Jan 2017

Planar Array Of Right-Angled Isosceles Triangular Microstrip Antenna Using Koch And Meander Lines For The Internet Of Things, Manisha Gupta, Vinita Mathur

Turkish Journal of Electrical Engineering and Computer Sciences

An ultrawideband antenna array using a right-angled isosceles triangular microstrip antenna as a basic element is presented using inset feed for applications in the Internet of things. A Koch fractal antenna array with defected ground plane is used to generate multiband applications. Further, meander lines are added to increase the equivalent inductance that reduces the size of the antenna and increases the bandwidth and gain. Antenna arrays have been constructed and experimentally studied. The measured results show good agreement with the numerical prediction and wideband operation.


Online Health Recommendation System: A Social Support Perspective, Tareq Nasralah, Cherie Noteboom, Abdullah Wahbeh, Mohammad Aref Al-Ramahi Jan 2017

Online Health Recommendation System: A Social Support Perspective, Tareq Nasralah, Cherie Noteboom, Abdullah Wahbeh, Mohammad Aref Al-Ramahi

Research & Publications

Online Health Communities (OHC) aim to support patients through offer them the opportunities to exchange support with others. However, patients have difficulties and problems locating expertise within the online health communities. In this regard, this study aims to create a patient recommender system to help users locate those with relevant experience and similar health status. Specifically, we aim to leverage the type of online social support users seek to determine the patient health status to build a patient status prediction model. Building the model will help create a peer recommendation system for online support group members to easily locate peers …


Information Hiding With Data Diffusion Using Convolutional Encoding For Super-Encryption, Jonathan Blackledge, Paul Tobin, J. Myeza, C.M. Adolfo Jan 2017

Information Hiding With Data Diffusion Using Convolutional Encoding For Super-Encryption, Jonathan Blackledge, Paul Tobin, J. Myeza, C.M. Adolfo

Articles

The unification of data encryption with information hiding methods continues to receive significant attention because of the importance of protecting encrypted information by making it covert. This is because one of the principal limitations in any cryptographic system is that encrypted data flags the potential importance of the data (i.e. the plaintext information that has been encrypted) possibly leading to the launch of an attack which may or may not be successful. Information hiding overcomes this limitation by making the data (which may be the plaintext or the encrypted plaintext) imperceptible, the security of the hidden information being compromised if …


Towards A Continuous Assessment Of Cognitive Workload For Smartphone Multitasking Users, Angel Jimenez-Molina, Hernan Lira Jan 2017

Towards A Continuous Assessment Of Cognitive Workload For Smartphone Multitasking Users, Angel Jimenez-Molina, Hernan Lira

H-Workload 2017: Models and Applications (Works in Progress)

The intermeshing of Smartphone interactions and daily activities depletes the availability of cognitive resources. This excessive demand may lead to several undesirable cognitive states, which can be avoided by continuously assessing the user cognitive workload. Recently, many attempts have emerged to assess this workload by using psycho physiological signals. This paper provides evidence that it is possible to train models that accurately identify in short time windows such cognitive workload by processing heart rate and blood oxygen saturation signals. This assessment could be applied in Smartphone notification delivery, interface adaptations or cognitive capabilities evaluation.


Human Performance Modelling In Manufacturing: Mental Workload And Task Complexity, Maria Chiara Leva, Lorenzo Comberti, Micaela Demichela, Rebecca Duane Jan 2017

Human Performance Modelling In Manufacturing: Mental Workload And Task Complexity, Maria Chiara Leva, Lorenzo Comberti, Micaela Demichela, Rebecca Duane

H-Workload 2017: Models and Applications (Works in Progress)

No abstract provided.


Distress And Worry As Mediators In The Relationship Between Psychosocial Risks And Upper Body Musculosketal Complaints In Highly Automated Manufacturing, Fiona Wixted, Leonard O'Sullivan Jan 2017

Distress And Worry As Mediators In The Relationship Between Psychosocial Risks And Upper Body Musculosketal Complaints In Highly Automated Manufacturing, Fiona Wixted, Leonard O'Sullivan

H-Workload 2017: Models and Applications (Works in Progress)

As a result of an upward trend in automation, the requirement for supervisory monitoring and consequently, cognitive demand has increased in automated manufacturing. The incidence of musculoskeletal disorders has also increased in the manufacturing sector. A model was developed based on survey data to test if distress and worry mediate the relationship between psychosocial factors (job control, cognitive demand, social isolation and skill discretion), stress states and upper body musculoskeletal complaints in highly automated manufacturing companies (n=235). Cognitive demand was shown to be related to higher distress in employees. The data raise the question about the link between job control …


Moving Between Automated And Manual Driving: Mental Workload And Performance Implications, Totsapon Butmee, Terry C. Lansdown Jan 2017

Moving Between Automated And Manual Driving: Mental Workload And Performance Implications, Totsapon Butmee, Terry C. Lansdown

H-Workload 2017: Models and Applications (Works in Progress)

Automated driving has been predicted to take-over from manual vehicle control in the near future. The driver’s role may then change from active operator to passive observer. Such technology offers the tantalising promise of improving driving safety. However, many studies have presented findings suggesting potentially adverse effects from automated driving systems, e.g., reduced situation awareness. Mental workload is also a key issue of concern for researchers in this area. Excessive mental workload has repeatedly been shown to be associated with degraded driving performance. Previously, most traffic psychology studies on mental workload have focused the manual driving task. However, a shift …


Managing Operator Mental Workload With Standards Based Decision Support, Maurice Wilkins Jan 2017

Managing Operator Mental Workload With Standards Based Decision Support, Maurice Wilkins

H-Workload 2017: Models and Applications (Works in Progress)

H-Workload 2017: The first international symposium on human mental workload, Dublin Institute of Technology, Dublin, Ireland, June 28-30.


Smart Workload Balancing, Ferdinand Coster Jan 2017

Smart Workload Balancing, Ferdinand Coster

H-Workload 2017: Models and Applications (Works in Progress)

The cognitive workload of operators working with automated systems should neither be too high nor too low. A static level of automation is unable to cope with systems that produce large fluctuations in cognitive workload, therefore a method for adaptive automation is proposed that could balance workload by intelligently choosing what to automate and when. To this end the concept of the Cognitive Workload Value factor is introduced, which takes into account both workload and situation awareness. This initial work introduces a possible framework for categorizing and using different workload and situation awareness measures.


How Useful Are Carboard Mock-Ups: The Use Of Different Levels Of Simulation Fidelity In Assessing Signallers' Workload, Andrew Marshall, James Murphy Jan 2017

How Useful Are Carboard Mock-Ups: The Use Of Different Levels Of Simulation Fidelity In Assessing Signallers' Workload, Andrew Marshall, James Murphy

H-Workload 2017: Models and Applications (Works in Progress)

Two techniques were utilised: the Bedford Scale and the NASA TLX. Assessments were made with two levels of fidelity. The first used a busy 15 minute scenario with seven different failure conditions using paper based layouts of the new signalling system. The second used a three dimensional representation of the proposed signal box layout for a busy one hour scenario. A key finding was that the new box could be run by two signallers with acceptable levels of workload, even with minor failures. A number of changes to the layout were proposed based on the experience of an hour's simulation. …


Facing Human Workload: The Resilient Ego: A Psychoanalytic Point Of View, Glauco Maria Genga, Maria Gabriella Pediconii Jan 2017

Facing Human Workload: The Resilient Ego: A Psychoanalytic Point Of View, Glauco Maria Genga, Maria Gabriella Pediconii

H-Workload 2017: Models and Applications (Works in Progress)

The paper aims to show new connections among Human Factors, Human Workload and Resilience. We intend: 1) to highlight the role of subject in facing the human workload, inflected as demanding tasks and emergency situations; 2) to show how psychoanalysis can provide novel insights, not only into human errors, but also into human resilience. They have a common denominator, at least in part: the role of subjective contributions even in demanding situations. Human workload includes a work for satisfaction. We recall also the case study of US Airways Flight 1549 water landing (the so called “Miracle on the Hudson”), which …


A Validated Description Of How Crew Manage Flight Operations For Two-Pilot And Reduced Crew Operations, Nick Mcdonnell, Alison Kay, Margaret Ryan, Rabea Morrison, Rolf Zon Jan 2017

A Validated Description Of How Crew Manage Flight Operations For Two-Pilot And Reduced Crew Operations, Nick Mcdonnell, Alison Kay, Margaret Ryan, Rabea Morrison, Rolf Zon

H-Workload 2017: Models and Applications (Works in Progress)

This research provides a rich validated description of how crew manage workload for both two-pilot and reduced crew operations. It outlines flight operations modelling, operational narratives, requirements and scenarios validated with expert advisers from the EU-FP7 ACROSS Project. The crew are considered to be the managers of the operation who receive integrated technical support to help them manage flight operations across of three configurations i.e. 1) standard two-crew configuration, 2) reduced crew under normal operations 3) reduced-crew under non-normal operations developed within the FP7 EU-funded ACROSS (Advanced Cockpit for the Reduction Of Stress and Workload) project.


Petrochemical Plant Console Operator Workload:The Issues, David A. Strobhar Jan 2017

Petrochemical Plant Console Operator Workload:The Issues, David A. Strobhar

H-Workload 2017: Models and Applications (Works in Progress)

The console operators of certain petrochemical processes must maintain high levels of performance during process upsets or endanger personnel safety and the environment. Mismanagement of an upset can result in explosions, fires, and the release of hazardous chemicals to the environment. The change in workload from steady state to upset operation is significant, with alarms and control changes that are of an order of magnitude. This paper describes the state of console activity in process plants, particularly the increase with key upsets. Quantitative data on the nature of the console operator’s position, its workload during normal operation, and the requirements …


Using Journals To Assess Non-Stem Student Learning In Stem Courses: A Case Study In Cybersecurity Education, Gary Kessler, Glenn S. Dardick, Douglas L. Holton Jan 2017

Using Journals To Assess Non-Stem Student Learning In Stem Courses: A Case Study In Cybersecurity Education, Gary Kessler, Glenn S. Dardick, Douglas L. Holton

Publications

Embry-Riddle Aeronautical University offers a minor course of study in cybersecurity as an option in our undergraduate Homeland Security program. Since the students are, by and large, social scientists, the focus of the program is to build hyper-awareness of how cybersecurity integrates within their professional aspirations rather than to provide cybersecurity career-level proficiency. Assessing student learning of the technical aspects cannot be performed using traditional tests, as they would not properly measure what the students are learning in a practical sense. Instead, we employ journals and self-reflection to ask the students to express and demonstrate their learning. Although somewhat harder …


Preliminary Analysis Of Cyberterrorism Threats To Internet Of Things (Iot) Applications, Bilge Karabacak, Mobolarinwa Balogun, Hayretdin Bahsi Jan 2017

Preliminary Analysis Of Cyberterrorism Threats To Internet Of Things (Iot) Applications, Bilge Karabacak, Mobolarinwa Balogun, Hayretdin Bahsi

All Faculty and Staff Scholarship

The era of Internet of Things (IoT) being a combination of various networking and computing technologies already in a state of growth that introduces a new age of data aggregation mechanism and ubiquitous connectivity among physical objects. However, the most of the cyber threats still remain unsolved and may create huge impact on our lives. One of the possible major changes in impact landscape is the imminent physical results of cyber threats as IoT technologies enable closer interactions between humans and information systems. Although the cyber threats to critical infrastructures have been highly considered by the cyber security community, the …


A Day In The Life Of A Sim: Making Meaning Of Video Game Avatars And Behaviors, Jessica Stark Jan 2017

A Day In The Life Of A Sim: Making Meaning Of Video Game Avatars And Behaviors, Jessica Stark

Antioch University Dissertations & Theses

With video game usage--and criticism on its activity--on the rise, it may be helpful for the psychological community to understand what it actually means to play video games, and what the lived experience entails. This qualitative, phenomenological study specifically explores user behaviors and decisions in the simulated life video game, The Sims. Ten participants completed one- to two-hour long semi-structured interviews, and the data was transcribed, organized into 1,988 codes, which were clustered into 30 categories, and from which six themes ultimately emerged. These resulting themes are: self-representation; past, present, and future; purpose for play; self-reflection; co-creation; and familiarity. The …


A Semi-Automatic Grading Experience For Digital Ink Quizzes, Brooke Ellen Rhees Jan 2017

A Semi-Automatic Grading Experience For Digital Ink Quizzes, Brooke Ellen Rhees

Theses and Dissertations

Teachers who want to assess student learning and provide quality feedback are faced with a challenge when trying to grade assignments quickly. There is currently no system which will provide both a fast-to-grade quiz and a rich testing experience. Previous attempts to speed up grading time include NLP-based text analysis to automate grading and scanning in documents for manual grading with recyclable feedback. However, automated NLP systems all focus solely on text-based problems, and manual grading is still linear in the number of students. Machine learning algorithms exist which can interactively train a computer quickly classify digital ink strokes. We …


Measuring Presence: Hypothetical Quantitative Framework, Krzysztof Szczurowski, Matt Smith Jan 2017

Measuring Presence: Hypothetical Quantitative Framework, Krzysztof Szczurowski, Matt Smith

Conference papers

Virtual Reality Head - Mounted Display (HMD) manufacturers claim that consumer electronics can finally deliver a high degree of presence in virtual and remote environments. Certainly, current consumer-grade HMD systems offer rich and coherent mediated experiences of such environments. However, the very concept of presence is still a subject of debate, and researchers' investigation of the phenomenon of `presence' is based primarily on qualitative (i.e. questionnaire-based) assessments. Some researchers attempted to develop real-time, quantitative methods to facilitate more objective investigation of presence in mediated environments. Most such methodologies are derived from attempts to correlate presence with cardiovascular and electrodermal activity …


Multiparty Computations In Varying Contexts, Paul Laird, Sarah Jane Delany, Pierpaolo Dondio Jan 2017

Multiparty Computations In Varying Contexts, Paul Laird, Sarah Jane Delany, Pierpaolo Dondio

Conference papers

Recent developments in the automatic transformation of protocols into Secure Multiparty Computation (SMC) interactions, and the selection of appropriate schemes for their implementation have improved usabililty of SMC. Poor performance along with data leakage or errors caused by coding mistakes and complexity had hindered SMC usability. Previous practice involved integrating the SMC code into the application being designed, and this tight integration meant the code was not reusable without modification. The progress that has been made to date towards the selection of different schemes focuses solely on the two-party paradigm in a static set-up, and does not consider changing contexts. …


A Comparison Of Automatic Search Query Enhancement Algorithms That Utilise Wikipedia As A Source Of A Priori Knowledge, Kyle Goslin, Markus Hofmann Jan 2017

A Comparison Of Automatic Search Query Enhancement Algorithms That Utilise Wikipedia As A Source Of A Priori Knowledge, Kyle Goslin, Markus Hofmann

Conference papers

This paper describes the benchmarking and analysis of five Automatic Search Query Enhancement (ASQE) algorithms that utilise Wikipedia as the sole source for a priori knowledge. The contributions of this paper include: 1) A comprehensive review into current ASQE algorithms that utilise Wikipedia as the sole source for a priori knowledge; 2) benchmarking of five existing ASQE algorithms using the TREC-9 Web Topics on the ClueWeb12 data set and 3) analysis of the results from the benchmarking process to identify the strengths and weaknesses each algorithm. During the benchmarking process, 2,500 relevance assessments were performed. Results of these tests are …


Dynamic Behavior Analysis Of Android Applications For Malware Detection, Latika Singh, Markus Hofmann Jan 2017

Dynamic Behavior Analysis Of Android Applications For Malware Detection, Latika Singh, Markus Hofmann

Conference papers

Android is most popular operating system for smartphones and small devices with 86.6% market share (Chau 2016). Its open source nature makes it more prone to attacks creating a need for malware analysis. Main approaches for detecting malware intents of mobile applications are based on either static analysis or dynamic analysis. In static analysis, apps are inspected for suspicious patterns of code to identify malicious segments. However, several obfuscation techniques are available to provide a guard against such analysis. The dynamic analysis on the other hand is a behavior-based detection method that involves investigating the run-time behavior of the suspicious …


Impact Of Uri Canonicalization On Memento Count, Mat Kelly, Lulwah M. Alkwai, Michael L. Nelson, Michele C. Weigle, Herbert Van De Sompel Jan 2017

Impact Of Uri Canonicalization On Memento Count, Mat Kelly, Lulwah M. Alkwai, Michael L. Nelson, Michele C. Weigle, Herbert Van De Sompel

Computer Science Faculty Publications

Quantifying the captures of a URI over time is useful for researchers to identify the extent to which a Web page has been archived. Memento TimeMaps provide a format to list mementos (URI-Ms) for captures along with brief metadata, like Memento-Datetime, for each URI-M. However, when some URI-Ms are dereferenced, they simply provide a redirect to a different URI-M (instead of a unique representation at the datetime), often also present in the TimeMap. This infers that confidently obtaining an accurate count quantifying the number of non-forwarding captures for a URI-R is not possible using a TimeMap alone and that the …


Modeling Beta-Traces For Beta-Barrels From Cryo-Em Density Maps, Dong Si, Jing He Jan 2017

Modeling Beta-Traces For Beta-Barrels From Cryo-Em Density Maps, Dong Si, Jing He

Computer Science Faculty Publications

Cryo-electron microscopy (cryo-EM) has produced density maps of various resolutions. Although ά-helices can be detected from density maps at 5-8 angstrom resolutions, β-strands are challenging to detect at such density maps due to close-spacing of β-strands. The variety of shapes of β-sheets adds the complexity of β-strands detection from density maps. We propose a new approach to model traces of β-strands for β-barrel density regions that are extracted from cryo-EM density maps. In the test containing eight β-barrels extracted from experimental cryo-EM density maps at 5.5 angstrom-8.25 angstrom resolution, StrandRoller detected about 74.26% of the amino acids in the β-strands …


Homeomorphic Tetrahedralization Of Multi-Material Images With Quality And Fidelity Guarantees, Jing Xu, Andrey N. Chernikov Jan 2017

Homeomorphic Tetrahedralization Of Multi-Material Images With Quality And Fidelity Guarantees, Jing Xu, Andrey N. Chernikov

Computer Science Faculty Publications

We present a novel algorithm for generating three-dimensional unstructured tetrahedral meshes of multi-material images. The algorithm produces meshes with high quality since it provides a guaranteed dihedral angle bound of up to 19.47° for the output tetrahedra. In addition, it allows for user-specified guaranteed bounds on the two-sided Hausdorff distance between the boundaries of the mesh and the boundaries of the materials. Moreover, the mesh boundary is proved to be homeomorphic to the object surface. The algorithm is fast and robust, it produces a sufficiently small number of mesh elements that comply with these guarantees, as compared to other software. …