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2015

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Articles 12121 - 12150 of 12617

Full-Text Articles in Physical Sciences and Mathematics

Summary Tables: Stafford County, Virginia Shoreline Inventory Report, Marcia Berman, Karinna Nunez, Sharon Killeen, Tamia Rudnicky, Julie Bradshaw, Karen Duhring, David Stanhope, David Weiss, Carl Hershner Jan 2015

Summary Tables: Stafford County, Virginia Shoreline Inventory Report, Marcia Berman, Karinna Nunez, Sharon Killeen, Tamia Rudnicky, Julie Bradshaw, Karen Duhring, David Stanhope, David Weiss, Carl Hershner

Reports

The Shoreline Inventory Summary Tables quantify observed conditions based on river systems, such as the combined length of linear features (e.g. shoreline miles surveyed, miles of bulkhead and revetment), the total number of point features (e.g. docks, boathouses, boat ramps) & total acres of polygon features (tidal marshes).


The Future Of Science Education In Elementary School, Anah Soble Jan 2015

The Future Of Science Education In Elementary School, Anah Soble

The Synapse: Intercollegiate science magazine

No abstract provided.


Toward Mobile Robots Reasoning Like Humans, Jean Oh, Arne Suppe, Felix Duvallet, Abdeslam Boularias, Luis Navarro-Serment, Martial Hebert, Anthony Stentz, Jerry Vinokurov, Oscar Romero, Christian Lebiere, Robert Dean Jan 2015

Toward Mobile Robots Reasoning Like Humans, Jean Oh, Arne Suppe, Felix Duvallet, Abdeslam Boularias, Luis Navarro-Serment, Martial Hebert, Anthony Stentz, Jerry Vinokurov, Oscar Romero, Christian Lebiere, Robert Dean

Research Collection School Of Computing and Information Systems

Robots are increasingly becoming key players in human-robot teams. To become effective teammates, robots must possess profound understanding of an environment, be able to reason about the desired commands and goals within a specific context, and be able to communicate with human teammates in a clear and natural way. To address these challenges, we have developed an intelligence architecture that combines cognitive components to carry out high-level cognitive tasks, semantic perception to label regions in the world, and a natural language component to reason about the command and its relationship to the objects in the world. This paper describes recent …


Saliency-Guided Color-To-Gray Conversion Using Region-Based Optimization, Hao Du, Shengfeng He, Bin Sheng, Lizhuang Ma, Rynson W.H. Lau Jan 2015

Saliency-Guided Color-To-Gray Conversion Using Region-Based Optimization, Hao Du, Shengfeng He, Bin Sheng, Lizhuang Ma, Rynson W.H. Lau

Research Collection School Of Computing and Information Systems

Image decolorization is a fundamental problem for many real-world applications, including monochrome printing and photograph rendering. In this paper, we propose a new color-to-gray conversion method that is based on a region-based saliency model. First, we construct a parametric color-to-gray mapping function based on global color information as well as local contrast. Second, we propose a region-based saliency model that computes visual contrast among pixel regions. Third, we minimize the salience difference between the original color image and the output grayscale image in order to preserve contrast discrimination. To evaluate the performance of the proposed method in preserving contrast in …


Ciphercard: A Token-Based Approach Against Camera-Based Shoulder Surfing Attacks On Common Touchscreen Devices, Teddy Seyed, Xing-Dong Yang, Anthony Tang, Saul Greenberg, Jiawei Gu, Bin Zhu, Xiang Ciao Jan 2015

Ciphercard: A Token-Based Approach Against Camera-Based Shoulder Surfing Attacks On Common Touchscreen Devices, Teddy Seyed, Xing-Dong Yang, Anthony Tang, Saul Greenberg, Jiawei Gu, Bin Zhu, Xiang Ciao

Research Collection School Of Computing and Information Systems

We present CipherCard, a physical token that defends against shoulder-surfing attacks on user authentication on capacitive touchscreen devices. When CipherCard is placed over a touchscreen’s pin-pad, it remaps a user’s touch point on the physical token to a different location on the pin-pad. It hence translates a visible user password into a different system password received by a touchscreen, but is hidden from observers as well as the user. CipherCard enhances authentication security through Two-Factor Authentication (TFA), in that both the correct user password and a specific card are needed for successful authentication. We explore the design space of CipherCard, …


Profiling Web Archives For Efficient Memento Query Routing, Sawood Alam, Michael L. Nelson, Herbert Van De Sompel, Lyudmila L. Balakireva, Harihar Shankar, David S. H. Rosenthal Jan 2015

Profiling Web Archives For Efficient Memento Query Routing, Sawood Alam, Michael L. Nelson, Herbert Van De Sompel, Lyudmila L. Balakireva, Harihar Shankar, David S. H. Rosenthal

Computer Science Faculty Publications

No abstract provided.


A Dynamic Programming Algorithm For Finding The Optimal Placement Of A Secondary Structure Topology In Cryo-Em Data, Abhishek Biswas, Desh Ranjan, Mohammad Zubair, Jing He Jan 2015

A Dynamic Programming Algorithm For Finding The Optimal Placement Of A Secondary Structure Topology In Cryo-Em Data, Abhishek Biswas, Desh Ranjan, Mohammad Zubair, Jing He

Computer Science Faculty Publications

The determination of secondary structure topology is a critical step in deriving the atomic structures from the protein density maps obtained from electron cryomicroscopy technique. This step often relies on matching the secondary structure traces detected from the protein density map to the secondary structure sequence segments predicted from the amino acid sequence. Due to inaccuracies in both sources of information, a pool of possible secondary structure positions needs to be sampled. One way to approach the problem is to first derive a small number of possible topologies using existing matching algorithms, and then find the optimal placement for each …


Divergent Responses Of Atlantic Coastal And Oceanic Synechococcus To Iron Limitation, Katherine R. M. Mackey, Anton F. Post, Matthew R. Mcilvin, Gregory A. Cutter, Seth G. John, Mak A. Saito Jan 2015

Divergent Responses Of Atlantic Coastal And Oceanic Synechococcus To Iron Limitation, Katherine R. M. Mackey, Anton F. Post, Matthew R. Mcilvin, Gregory A. Cutter, Seth G. John, Mak A. Saito

OES Faculty Publications

Marine Synechococcus are some of the most diverse and ubiquitous phytoplankton, and iron (Fe) is an essential micronutrient that limits productivity in many parts of the ocean. To investigate how coastal and oceanic Atlantic Synechococcus strains acclimate to Fe availability, we compared the growth, photophysiology, and quantitative proteomics of two Synechococcus strains from different Fe regimes. Synechococcus strain WH8102, from a region in the southern Sargasso Sea that receives substantial dust deposition, showed impaired growth and photophysiology as Fe declined, yet used few acclimation responses. Coastal WH8020, from the dynamic, seasonally variable New England shelf, displayed a multitiered, hierarchical cascade …


Predicting Carbon Isotope Discrimination In Eelgrass (Zostera Marina L.) From The Environmental Parameters- Light, Flow, And [Dic], Meredith L. Mcpherson, Richard C. Zimmerman, Victoria J. Hill Jan 2015

Predicting Carbon Isotope Discrimination In Eelgrass (Zostera Marina L.) From The Environmental Parameters- Light, Flow, And [Dic], Meredith L. Mcpherson, Richard C. Zimmerman, Victoria J. Hill

OES Faculty Publications

Isotopic discrimination against 13C during photosynthesis is determined by a combination of environmental conditions and physiological mechanisms that control delivery of CO2 to RUBISCO. This study investigated the effects of light, flow, dissolved inorganic carbon (DIC) concentration, and its speciation, on photosynthetic carbon assimilation of Zostera marinaL. (eelgrass) using a combination of laboratory experiments and theoretical calculations leading to a mechanistic understanding of environmental conditions that influence leaf carbon uptake and determine leaf stable carbon isotope signatures δ13C. Photosynthesis was saturated with respect to flow at low velocity ~ 3 cm s-1, but …


Predicting Effects Of Ocean Warming, Acidification, And Water Quality On Chesapeake Region Eelgrass, Richard C. Zimmerman, Victoria J. Hill, Charles L. Gallegos Jan 2015

Predicting Effects Of Ocean Warming, Acidification, And Water Quality On Chesapeake Region Eelgrass, Richard C. Zimmerman, Victoria J. Hill, Charles L. Gallegos

OES Faculty Publications

Although environmental requirements of seagrasses have been studied for years, reliable metrics for predicting their response to current or future conditions remain elusive. Eelgrass (Zostera marina L.) populations of the Chesapeake region lie near the southern limit of their range in the Western North Atlantic, exposing them to increasing thermal stress as the climate warms. However, CO2 stimulated photosynthesis may offset some of the negative effects of temperature stress. The combined effects of temperature, CO2, and light availability controlled by water quality and epiphytes were explored using GrassLight, a bio-optical model that provided a predictive …


Understanding Ocean Acidification Impacts On Organismal To Ecological Scales, Andreas J. Andersson, David I. Kline, Peter J. Edmunds, Stephen D. Archer, Nina Bednarsek, Robert C. Carpenter, Meg Chadsey, Philip Goldstein, Andrea G. Grottoli, Thomas P. Hurst, Andrew L. King, Janet E. Kübler, Ilsa B. Kuffner, Katherine R.M. Mackey, Bruce A. Menge, Adina Paytan, Ulf Riebesell, Astrid Schnetzer, Mark E. Warner, Richard C. Zimmerman Jan 2015

Understanding Ocean Acidification Impacts On Organismal To Ecological Scales, Andreas J. Andersson, David I. Kline, Peter J. Edmunds, Stephen D. Archer, Nina Bednarsek, Robert C. Carpenter, Meg Chadsey, Philip Goldstein, Andrea G. Grottoli, Thomas P. Hurst, Andrew L. King, Janet E. Kübler, Ilsa B. Kuffner, Katherine R.M. Mackey, Bruce A. Menge, Adina Paytan, Ulf Riebesell, Astrid Schnetzer, Mark E. Warner, Richard C. Zimmerman

OES Faculty Publications

Ocean acidification (OA) research seeks to understand how marine ecosystems and global elemental cycles will respond to changes in seawater carbonate chemistry in combination with other environmental perturbations such as warming, eutrophication, and deoxygenation. Here, we discuss the effectiveness and limitations of current research approaches used to address this goal. A diverse combination of approaches is essential to decipher the consequences of OA to marine organisms, communities, and ecosystems. Consequently, the benefits and limitations of each approach must be considered carefully. Major research challenges involve experimentally addressing the effects of OA in the context of large natural variability in seawater …


Tropical North Atlantic Subsurface Warming Events As A Fingerprint For Amoc Variability During Marine Isotope Stage 3, Andrew O. Parker, Matthew W. Schmidt, Ping Chang Jan 2015

Tropical North Atlantic Subsurface Warming Events As A Fingerprint For Amoc Variability During Marine Isotope Stage 3, Andrew O. Parker, Matthew W. Schmidt, Ping Chang

OES Faculty Publications

The role of Atlantic Meridional Overturning Circulation (AMOC) as the driver of Dansgaard-Oeschger (DO) variability that characterized Marine Isotope Stage 3 (MIS 3) has long been hypothesized. Although there is ample proxy evidence suggesting that DO events were robust features of glacial climate, there is little data supporting a link with AMOC. Recently, modeling studies and subsurface temperature reconstructions have suggested that subsurface warming across the tropical North Atlantic can be used to fingerprint a weakened AMOC during the deglacial because a reduction in the strength of the western boundary current allows warm salinity maximum water of the subtropical gyre …


The Influence Of Sea Ice And Snow Cover And Nutrient Availability On The Formation Of Massive Under-Ice Phytoplankton Blooms In The Chukchi Sea, Jinlun Zhang, Carin Ashjian, Robert Campbell, Yvette H. Spitz, Michael Steele, Victoria Hill Jan 2015

The Influence Of Sea Ice And Snow Cover And Nutrient Availability On The Formation Of Massive Under-Ice Phytoplankton Blooms In The Chukchi Sea, Jinlun Zhang, Carin Ashjian, Robert Campbell, Yvette H. Spitz, Michael Steele, Victoria Hill

OES Faculty Publications

A coupled biophysical model is used to examine the impact of changes in sea ice and snow cover and nutrient availability on the formation of massive under-ice phytoplankton blooms (MUPBs) in the Chukchi Sea of the Arctic Ocean over the period 1988–2013. The model is able to reproduce the basic features of the ICESCAPE (Impacts of Climate on EcoSystems and Chemistry of the Arctic Pacific Environment) observed MUPB during July 2011. The simulated MUPBs occur every year during 1988–2013, mainly in between mid-June and mid-July. While the simulated under-ice blooms of moderate magnitude are widespread in the Chukchi Sea, MUPBs …


Living On The Margin In The Anthropocene: Engagement Arenas For Sustainability Research And Action At The Ocean-Land Interface, B. C. Glavovic, K. Limburg, K-K. Liu, K-C. Emeis, H. Thomas, H. Kremer, B. Avril, J. Zhang, M. R. Mulholland, M. Glaser, D. P. Swaney Jan 2015

Living On The Margin In The Anthropocene: Engagement Arenas For Sustainability Research And Action At The Ocean-Land Interface, B. C. Glavovic, K. Limburg, K-K. Liu, K-C. Emeis, H. Thomas, H. Kremer, B. Avril, J. Zhang, M. R. Mulholland, M. Glaser, D. P. Swaney

OES Faculty Publications

The advent of the Anthropocene underscores the need to develop and implement transformative governance strategies that safeguard the Earth's life-support systems, most critically at the ocean-land interface - the Margin. The seaward realm of the Margin is the new frontier for resource exploitation and colonization to meet the needs of coastal nations and humanity overall. Here, we spotlight the pivotal role of the Margin for planetary resilience and sustainability, highlight priority issues, and outline a research strategy which aims to: (a) better understand Margin social-ecological systems; (b) guide sustainable development of Margin resources; (c) design governance regimes to reverse unsustainable …


Heterotrophic And Autotrophic Contribution To Dinitrogen Fixation In The Gulf Of Aqaba, Eyal Rahav, Barak Herut, Margaret R. Mulholland, Natalia Belkin, Hila Elifantz, Ilana Berman-Frank Jan 2015

Heterotrophic And Autotrophic Contribution To Dinitrogen Fixation In The Gulf Of Aqaba, Eyal Rahav, Barak Herut, Margaret R. Mulholland, Natalia Belkin, Hila Elifantz, Ilana Berman-Frank

OES Faculty Publications

We evaluated the seasonal contribution of heterotrophic and autotrophic diazotrophy to the total dinitrogen (N2) fixation in the photic zone of a pelagic station in the northern Gulf of Aqaba, Red Sea. N2 fixation rates were highest during a Trichodesmium bloom in winter (0.7 nmol N l-1 d-1), decreased 7-fold 1 wk later throughout the upper 200 m (~0.1 nmol N l-1) d-1), and were significantly coupled with both primary and bacterial productivity. N2 fixation rates were generally higher in the upper 200 m (~0.4 nmol N l-1 …


The Geotraces Intermediate Data Product 2014, Edward Mawji, Reiner Schlitzer, Elena M. Dodas, Cyril Abadie, Wafa Abouchami, Robert F. Anderson, Gregory A. Cutter Jan 2015

The Geotraces Intermediate Data Product 2014, Edward Mawji, Reiner Schlitzer, Elena M. Dodas, Cyril Abadie, Wafa Abouchami, Robert F. Anderson, Gregory A. Cutter

OES Faculty Publications

The GEOTRACES Intermediate Data Product 2014 (IDP2014) is the first publicly available data product of the international GEOTRACES programme, and contains data measured and quality controlled before the end of 2013. It consists of two parts: (1) a compilation of digital data for more than 200 trace elements and isotopes (TEls) as well as classical hydrographic parameters, and (2) the eGEOTRACES Electronic Atlas providing a strongly inter-linked on-line atlas including more than 300 section plots and 90 animated 3D scenes. The IDP2014 covers the Atlantic, Arctic, and Indian oceans, exhibiting highest data density in the Atlantic. The TEI data in …


Genetic Indicators Of Iron Limitation In Wild Populations Of Thalassiosira Oceanica From The Northeast Pacific Ocean, P. Dreux Chappell, Leann P. Whitney, Joselynn R. Wallace, Adam I. Darer, Samua Jean-Charles, Bethany D. Jenkins Jan 2015

Genetic Indicators Of Iron Limitation In Wild Populations Of Thalassiosira Oceanica From The Northeast Pacific Ocean, P. Dreux Chappell, Leann P. Whitney, Joselynn R. Wallace, Adam I. Darer, Samua Jean-Charles, Bethany D. Jenkins

OES Faculty Publications

Assessing the iron (Fe) nutritional status of natural diatom populations has proven challenging as physiological and molecular responses can differ in diatoms of the same genus. We evaluated expression of genes encoding flavodoxin (FLDA1) and an Fe-starvation induced protein (ISIP3) as indicators of Fe limitation in the marine diatom Thalassiosira oceanica. The specificity of the response to Fe limitation was tested in cultures grown under Fe-and macronutrient-deficient conditions, as well as throughout the diurnal light cycle. Both genes showed a robust and specific response to Fe limitation in laboratory cultures and were detected in small volume samples collected from …


Design And Implementation Of Ir And Laser-Based Electronic Ciphering Systems, Feyzi̇ Akar, Osman Aşkin Jan 2015

Design And Implementation Of Ir And Laser-Based Electronic Ciphering Systems, Feyzi̇ Akar, Osman Aşkin

Turkish Journal of Electrical Engineering and Computer Sciences

This paper describes the design and implementation of infrared (IR) and laser-based electronic ciphering systems for use in both indoor and outdoor wireless remote control applications. To communicate between a user and a lock module in a secure way, the proposed systems utilize IR and laser frequencies instead of radio frequencies. Each proposed system has its specific security design. A new communication protocol is also generated, which is compatible for use with IR and laser technologies. The proposed electronic ciphering systems' prototypes are realized together with software and hardware components. They are instrumented using the peripheral interface controller series microcontrollers. …


Simulation Of Locating Buried Objects Via Fringe Pattern-Based Measurements In An Optical Fiber Sensor-Integrated Continuous-Wave Ground-Penetrating Radar System, Asaf Behzat Şahi̇n, Hati̇ce Gonca Bulur Jan 2015

Simulation Of Locating Buried Objects Via Fringe Pattern-Based Measurements In An Optical Fiber Sensor-Integrated Continuous-Wave Ground-Penetrating Radar System, Asaf Behzat Şahi̇n, Hati̇ce Gonca Bulur

Turkish Journal of Electrical Engineering and Computer Sciences

A new ground-penetrating radar system that can determine the depth and position of a buried metal cylinder, which is the combination of an optical fiber sensor (OFS), continuous-wave transmitter, and optical communication link, is proposed and simulated in the MATLAB and Optiwave program packages. Employing an optical sensor instead of a standard radio frequency (RF) receiver offers the advantage of preventing electromagnetic interference along the sensor's main unit cable and lower amplification noise. In this paper, the electric field distribution at the OFS due to reflections from the soil surface and the buried object is obtained mathematically using Green's function. …


Sensitivity Analysis And Optimum Design For The Stator Of Synchronous Reluctance Machines Using The Coupled Finite Element And Taguchi Methods, Hossein Azizi, Abolfazl Vahedi Jan 2015

Sensitivity Analysis And Optimum Design For The Stator Of Synchronous Reluctance Machines Using The Coupled Finite Element And Taguchi Methods, Hossein Azizi, Abolfazl Vahedi

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents an investigation of the effect and optimization of stator geometry design parameters on the performance of synchronous reluctance machines (SynRMs). The level of importance of the stator design variable on the characteristic of the SynRM is determined using both the Taguchi method and a parametric analysis. An optimum design parameter combination is obtained using sensitivity analysis along with signal-to-noise ratio results. The 2-dimensional finite element model (FEM) of a SynRM is used to perform a sensitivity analysis and construct a Taguchi design of the experiment. The FEM simulation results confirm that the performance of the SynRM can …


Design Of A Novel Usb Crypto Bridge Device, Orhan Şengül Jan 2015

Design Of A Novel Usb Crypto Bridge Device, Orhan Şengül

Turkish Journal of Electrical Engineering and Computer Sciences

Information technologies have emerging use of portable drives. Hence, the readability and security of the content is at great risk in the event that it is lost or stolen. An effective solution to this issue is the use of removable disks in encrypted form. In this paper, a novel USB device that has cryptobridge capability is proposed.


A New Cascaded Multilevel Inverter With Series And Parallel Connection Ability Of Dc Voltage Sources, Ebrahim Babaei, Saeed Sheermohammadzadeh Gowgani, Mehran Sabahi Jan 2015

A New Cascaded Multilevel Inverter With Series And Parallel Connection Ability Of Dc Voltage Sources, Ebrahim Babaei, Saeed Sheermohammadzadeh Gowgani, Mehran Sabahi

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a new multilevel inverter is proposed based on the connection of DC voltage sources in series and parallel. The proposed topology is composed of series basic units that consist of series and parallel connections of DC voltage sources. The values of the DC voltage sources differ from one unit to another. A new algorithm to determine the magnitude of the DC voltage sources of the proposed structure is presented. All of the related equations for the proposed multilevel inverter are extracted and the optimum structure from several points of view such as the maximum blocked voltage by …


Adaptive Network-Based Inference System Models On Multiband Patch Antenna Design, Erdem Demi̇rci̇oğlu, Murat Hüsnü Sazli, Orhan Şengül, Şehabeddi̇n Taha İmeci̇, Hakki Alparslan Ilgin Jan 2015

Adaptive Network-Based Inference System Models On Multiband Patch Antenna Design, Erdem Demi̇rci̇oğlu, Murat Hüsnü Sazli, Orhan Şengül, Şehabeddi̇n Taha İmeci̇, Hakki Alparslan Ilgin

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, an adaptive network-based fuzzy inference system (ANFIS) for multiband microstrip patch antenna (MMPA) modeling is proposed. The MMPA includes a single patch with inverted L-shaped stubs on the edges. The antenna production process needs iterative runs of the electromagnetic (EM) simulator, fabricating and testing the simulated antenna to find the optimum geometry. Production processes (design, simulation, fabrication, and testing) and the cost computation time add to the overall manufacturing expenses. A computer-aided modeling approach using the ANFIS is developed and trained with data acquired from the EM simulators, Sonnet Suites and AWR AXIEM, and measurement data. The …


Designing And Implementing A Reliable Thermal Monitoring System Based On The 1-Wire Protocol On Fpga For A Leo Satellite, Reza Omidi Gosheblagh, Karim Mohammadi Jan 2015

Designing And Implementing A Reliable Thermal Monitoring System Based On The 1-Wire Protocol On Fpga For A Leo Satellite, Reza Omidi Gosheblagh, Karim Mohammadi

Turkish Journal of Electrical Engineering and Computer Sciences

Thermal control and monitoring is one of the most important factors in the design of satellite systems. An appropriate thermal design should make sure that the satellite's sensitive components remain in their nominated range, even under the vacuum condition of outer space. To achieve this purpose, a reliable and stable monitoring system is required. This paper proposes a monitoring system based on the 1-wire protocol, which provides the reliability requirements in the sensor networking and bus controller sections. In the networking section, we outline some practical topologies and discuss on their complexity and reliability. Despite the fact that the point-to-point …


Short-Term Load Forecasting Using Mixed Lazy Learning Method, Seyed-Masoud Barakati, Ali Akbar Gharaveisi, Seyed-Mohammad Reza Rafiei Jan 2015

Short-Term Load Forecasting Using Mixed Lazy Learning Method, Seyed-Masoud Barakati, Ali Akbar Gharaveisi, Seyed-Mohammad Reza Rafiei

Turkish Journal of Electrical Engineering and Computer Sciences

A novel short-term load forecasting method based on the lazy learning (LL) algorithm is proposed. The LL algorithm's input data are electrical load information, daily electricity consumption patterns, and temperatures in a specified region. In order to verify the ability of the proposed method, a load forecasting problem, using the Pennsylvania-New Jersey-Maryland Interconnection electrical load data, is carried out. Three LL models are proposed: constant, linear, and mixed models. First, the performances of the 3 developed models are compared using the root mean square error technique. The best technique is then selected to compete with the state-of-the-art neural network (NN) …


Temporal Logic Extension For Self-Referring, Nonexistence, Multiple Recurrence, And Anterior Past Events, Şadi̇ Evren Şeker Jan 2015

Temporal Logic Extension For Self-Referring, Nonexistence, Multiple Recurrence, And Anterior Past Events, Şadi̇ Evren Şeker

Turkish Journal of Electrical Engineering and Computer Sciences

This study focuses on the possible extensions of current temporal logics. In this study, 4 extensions are proposed: self-referring events, nonexisting events, multiple recurrence of events, and an improvement on anterior past events. Each of these extensions is on a different level of temporal logics. The main motivation behind the extensions is the temporal analysis of Turkish. Similar to temporal logic studies built on other natural languages, like French, Ukrainian, Italian, Korean, English, or Romanian, this is the first time that the Turkish language has been deeply questioned in the sense of computable temporal logic using the view of a …


Mersenne Twister-Based Rfid Authentication Protocol, Mehmet Hi̇lal Özcanhan, Gökhan Dalkiliç Jan 2015

Mersenne Twister-Based Rfid Authentication Protocol, Mehmet Hi̇lal Özcanhan, Gökhan Dalkiliç

Turkish Journal of Electrical Engineering and Computer Sciences

This work presents an ultra-lightweight, cryptographic, mutual authentication protocol for radio-frequency identification (RFID) tags. The proposed scheme is more secure than its predecessors. The vulnerabilities of previous schemes based on triangular functions and rotation have been demonstrated in traditional and rotational cryptanalysis. In this paper, we summarize the successful attacks on previous schemes and demonstrate further attacks on 3 recent ultra-lightweight protocols. Next, we present a proposal that resists all of the known passive attacks. The proposal obeys the properties and rules of addition-rotation-XOR with constants systems. The proposed scheme inserts parts of advanced encryption standard S-boxes into the temperings …


Control Of Oxygen Excess Ratio In A Pem Fuel Cell System Using High-Order Sliding-Mode Controller And Observer, Seyed Mehdi Rakhtala, Abolfazl Ranjbar Noei, Reza Ghaderi, Elio Usai Jan 2015

Control Of Oxygen Excess Ratio In A Pem Fuel Cell System Using High-Order Sliding-Mode Controller And Observer, Seyed Mehdi Rakhtala, Abolfazl Ranjbar Noei, Reza Ghaderi, Elio Usai

Turkish Journal of Electrical Engineering and Computer Sciences

The main objective of this manuscript is to design a high-order sliding-mode observer to provide finite time estimation of unmeasurable states (x_4: oxygen mass, x_5: nitrogen mass) together with the oxygen excess ratio (ratio of the input oxygen flow to the reacted oxygen flow in the cathode). This is done by applying second-order sliding modes through either super twisting or suboptimal controllers to control the proton exchange membrane fuel cell's breathing. The estimated oxygen excess ratio is controlled in a closed-loop system using 2 distinct sliding-mode approaches: a cascaded super twisting controller and a single-loop suboptimal structure. Simulation results are …


A Robust Algorithm Based On A Failure-Sensitive Matrix For Fault Diagnosis Of Power Systems: An Application On Power Transformers, Yunus Bi̇çen, Faruk Aras Jan 2015

A Robust Algorithm Based On A Failure-Sensitive Matrix For Fault Diagnosis Of Power Systems: An Application On Power Transformers, Yunus Bi̇çen, Faruk Aras

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a robust algorithm for fault diagnosis of power system equipment based on a failure-sensitive matrix (FSM) is presented. The FSM is a dynamic matrix structure updated by multiple measurements (online) and test results (offline) on the systems. The algorithm uses many different artificial intelligence and expert system methods for adaptively detecting the location of faults, emerging failures, and causes of failures. In this algorithm, all data obtained from the power transformer, which have various nonlinear input and output parameters, are processed using the parallel matrix structure of the FSM to reach a global solution quickly. The parameters …


Dynamic Modeling Of Modular Fuel Cell For Maximum Power Point Tracking And Torque Ripple Reduction In Direct Torque Control Of Induction Motor, Majid Valizadeh, Mohammad Reza Feyzi, Ebrahim Babaei, Mehran Sabahi Jan 2015

Dynamic Modeling Of Modular Fuel Cell For Maximum Power Point Tracking And Torque Ripple Reduction In Direct Torque Control Of Induction Motor, Majid Valizadeh, Mohammad Reza Feyzi, Ebrahim Babaei, Mehran Sabahi

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a comprehensive dynamic model of a proton exchange membrane fuel cell (FC) based on the electrical empirical model. The presented model is useful for online control as well as having suitable accuracy. FC stacks produce a DC voltage with a ratio of 2:1 in output from no-load to full-load. In vehicles that are equipped with FCs, the output voltage of the FC is drastically changed because the power and torque of the vehicle change with the driving cycle. In order to improve the performance of the direct torque control of induction motors, the modular structure of a …