Computer Sciences Commons^™

Anfis-Based Estimation Of Pv Module Equivalent Parameters: Application To A Stand-Alone Pv System With Mppt Controller, Ahmet Afşi̇n Kulaksiz

Turkish Journal of Electrical Engineering and Computer Sciences

The performance and system cost of photovoltaic (PV) systems can be improved by employing high-efficiency power conditioners with maximum power point tracking (MPPT) methods. Fast implementation and accurate operation of MPPT controllers can be realized by modeling the characteristics of PV modules, obtaining equivalent parameters. In this study, adaptive neuro-fuzzy inference systems (ANFISs) have been used to obtain 3 of the parameters in a single-diode model of PV cells, namely series resistance, shunt resistance, and diode ideality factor. The input parameters of ANFISs are a material-type of PV modules, short circuit current, open circuit voltage, and unit area under the …

Adaptive Control Of A Time-Varying Rotary Servo System Using A Fuzzy Model Reference Learning Controller With Variable Adaptation Gain, Ömer Aydoğdu, Özdemi̇r Alkan

Turkish Journal of Electrical Engineering and Computer Sciences

The constant parameters in a conventional fuzzy controller lead to a poor performance for time-varying systems. In this study, a fuzzy model reference learning controller (FMRLC) with a newly defined variable adaptation gain is designed and implemented in the adaptive fuzzy control of a time-varying rotary servo (TVRS) system. In the design of the FMRLC, a knowledge-base modification algorithm with variable adaptation gain is used instead of a fuzzy relation table. Hence, it is provided that the learning and adaptation mechanism continuously updates the knowledge base of the adaptive fuzzy controller against any parameter variations, such as changing loads. By …

Optimized Operation And Maintenance Costs To Improve System Reliability By Decreasing The Failure Rate Of Distribution Lines, Hamed Hashemi Dezaki, Seyed Hossein Hosseinian, Hossein Askarian Abyaneh, Seyed Mohammad Mousavi Agah

Turkish Journal of Electrical Engineering and Computer Sciences

Improving distribution system reliability has received a great deal of attention in recent years. Because of the limitation in expected budgets, it is desirable to determine the most efficient strategy to improve system reliability. This paper proposes a novel method to determine the optimized operation and maintenance costs in order to decrease the failure of system components. The proposed objective function includes the average system frequency interruption index (ASIFI) value. To achieve the best strategy to decrease failures of system components, it is necessary to find the minimum value of the objective function, considering the constraints of operation and maintenance …

Design Of Information Retrieval Experiments: The Sufficient Topic Set Size For Providing An Adequate Level Of Confidence, Beki̇r Taner Di̇nçer

Turkish Journal of Electrical Engineering and Computer Sciences

In the current design of information retrieval (IR) experiments, a sample of 50 topics is generally agreed to be sufficient in size to perform dependable system evaluations. This article presents the detailed and formal explanation of how the second fundamental theorem of probability, the central limit theorem, can be used for the estimation of the sufficient size of a topic sample. The research performed in this article, using past Text Retrieval Conference data, reveals that, on average, 50 topics will be sufficient to provide a confidence level at or above 95% if the null hypothesis of an equal population mean …

Compact Microstrip Antenna With Metamaterial For Wideband Applications, Han Xiong, Jing-Song Hong, Ming-Tao Tan, Bing Li

Turkish Journal of Electrical Engineering and Computer Sciences

An improved metamaterial antenna, with a compact size of 27.8 x 31.9 x 0.794 mm^3, fed by an offset-microstrip line, is proposed. The total size is slightly reduced and the measured impedance bandwidth is 4.08-7.83 GHz for a return loss of \mid S_{11}\mid < -10 dB. Compared with the original patch antenna, the bandwidth of the proposed antenna is 550 MHz broader and has a lower resonant frequency. The simulated gain of the antenna is more than 2 dB, with a peak of about 6 dB at 6.8 GHz. Moreover, the antenna has strong radiation in the horizontal direction for some specific applications within the entire band.

A Novel Dynamic Bandwidth Selection Method For Thinning Noisy Point Clouds, Mehmet Öztürk, Zeynep Hasirci

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we propose a dynamic bandwidth selection method for thinning noisy point clouds into curves. Due to the nonhomogeneous distribution of noise or varying curvature of the data, the thinning procedure requires a dynamically adjusted bandwidth along the curve. On the other hand, the selected local region must be sorted along a suitable direction vector for local curve fitting purposes. The contribution of this paper to the field is 2-folded: first, a normalized eigenvalue analysis-based method is used to determine the best local bandwidth. The second task is getting a good regression line of the local region for …

Optimal Placement And Sizing Of Distributed Generations In Distribution Systems For Minimizing Losses And Thd_V Using Evolutionary Programming, Aida Fazliana Abdul Kadir, Azah Mohamed, Hussain Shareef, Mohd Zamri Che Wanik

Turkish Journal of Electrical Engineering and Computer Sciences

Growing concerns over environmental impacts, improvement of the overall network conditions, and rebate programs offered by governments have led to an increase in the number of distributed generation (DG) units in commercial and domestic electric power production. However, a large number of DG units in a distribution system may sometimes contribute to high levels of harmonic distortion, even though the emission levels of the individual DG units comply with the harmonic standards. It is known that the nonoptimal size and nonoptimal placement of DG units may lead to high power losses, bad voltage profiles, and harmonic propagations. Therefore, this paper …

Multi-Objective Weighted Sum Approach Model Reduction By Routh-Pade Approximation Using Harmony Search, Hasan Nasiri Soloklo, Malihe Maghfoori Farsangi

Turkish Journal of Electrical Engineering and Computer Sciences

A new weighted-sum multiobjective approach is investigated for order reduction based on Routh--Padé approximation, in which the harmony search algorithm is used to optimize the reduced-order model's parameters. In this method, apart from minimizing the errors between a set of subsequent time moments/Markov parameters of the system and those of the model, the error between the singular values of the reduced-order system and those of the original system is minimized. The Routh criterion is applied for specifying the stability conditions. The stability condition is then considered as a constraint in the optimization problem. To present the ability of the proposed …

Ssr Mitigation With Sssc Thanks To Fuzzy Control, Seyed Mohammad Hassan Hosseini, Hadi Samadzadeh, Javad Olamaei, Murtaza Farsadi

Turkish Journal of Electrical Engineering and Computer Sciences

This paper deals with the capability of a static synchronous series compensator (SSSC) to attenuate the subsynchronous resonance (SSR). Two well-known controllers are designed, namely a conventional damping controller (CDC) and fuzzy logic damping controller (FLDC). These 2 damping controllers are added to a main control loop of a SSSC operating as a SSR damping controller. It should be noted that, to optimize the parameters of the CDC, a versatile optimization technique is implemented, namely particle swarm optimization (PSO). A comprehensive comparison between the 2 control methods is carried out for different operational conditions. To observe the superior performance of …

Minimal Controller Synthesis Algorithms With Output Feedback And Their Generalization, Ata Sevi̇nç

Turkish Journal of Electrical Engineering and Computer Sciences

This paper proposes several improvements in the minimal controller synthesis algorithms, which were developed for a class of nonlinear systems with uncertainties. The major proposition is that only the output feedback is enough to control some nonlinear systems without an observer while the existing algorithms require the complete state feedback. Next, the extended version and the parameter identification technique of the minimal controller synthesis algorithm are combined in a single method estimating some more parameters for some known forms of nonlinearities. This is applicable with or without the improvement of removing the need for using the complete state feedback. It …

Negative Selection Algorithm For Dengue Outbreak Detection, Maryam Mousavi, Azuraliza Abu Bakar, Suhaila Zainudin, Zalizah Awang Long, Mazrura Sahani, Mohammadmahdi Vakilian

Turkish Journal of Electrical Engineering and Computer Sciences

Dengue is a critical communicable and vector-borne disease and is becoming a serious concern in Malaysia. It is important to have an early detection system that could provide immediate action, such as the control of dengue transmission at a specific location. However, the available strategy and action may give long-term effects to the community since inaccurate decision making or prediction may lead to other circumstances. Moreover, the need to have a system that can detect the outbreak in a reasonable amount of time is critical. In this study, a nature-inspired computing technique, the artificial immune system (AIS), is used for …

A Video-Based Eye Pupil Detection System For Diagnosing Bipolar Disorder, Gökay Akinci, Edi̇z Polat, Orhan Murat Koçak

Turkish Journal of Electrical Engineering and Computer Sciences

Eye pupil detection systems have become increasingly popular in image processing and computer vision applications in medical systems. In this study, a video-based eye pupil detection system is developed for diagnosing bipolar disorder. Bipolar disorder is a condition in which people experience changes in cognitive processes and abilities, including reduced attentional and executive capabilities and impaired memory. In order to detect these abnormal behaviors, a number of neuropsychological tests are also designed to measure attentional and executive abilities. The system acquires the position and radius information of eye pupils in video sequences using an active contour snake model with an …

A Flexible Rule-Based Framework For Pilot Performance Analysis In Air Combat Simulation Systems, Ömer Faruk Arar, Kürşat Ayan

Turkish Journal of Electrical Engineering and Computer Sciences

Air combat simulation systems (ACSSs) are developed to train fighter pilots (trainees) in a virtual combat environment. In general, an ACSS consists of the following stages: planning the scenario, training, flight analysis, and performance evaluation. In this paper, the details of the framework, which is developed to analyze and evaluate the performance of the trainees, is introduced. First, the evaluation criteria for the pilot performance are defined. Next, a dynamic pilot performance evaluation system is developed that can be controlled and modified by experienced instructor pilots (instructors/trainers) to define the performance criteria details using predefined evaluation parameters. The evaluation of …

Electronic Device, Display And Touch-Sensitive User Interface (Dec 2012), Michael E. Miller, Jerald J. Muszak, Michael J. Telek

AFIT Patents

Display devices and methods for operating the same are provided. In one embodiment, the display device has an electronic display having an active area for presenting visual content; a housing holding the electronic display and having an opening allowing a person to view a first portion of the active area; and a bezel about the opening, the bezel covering a second portion of the active area and providing a window through which at least a part of the second portion can be viewed. A sensor system senses when a person is close to touching the bezel or when a person …

Online Optimal Control Of Affine Nonlinear Discrete-Time Systems With Unknown Internal Dynamics By Using Time-Based Policy Update, Travis Dierks, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, the Hamilton-Jacobi-Bellman equation is solved forward-in-time for the optimal control of a class of general affine nonlinear discrete-time systems without using value and policy iterations. the proposed approach, referred to as adaptive dynamic programming, uses two neural networks (NNs), to solve the infinite horizon optimal regulation control of affine nonlinear discrete-time systems in the presence of unknown internal dynamics and a known control coefficient matrix. One NN approximates the cost function and is referred to as the critic NN, while the second NN generates the control input and is referred to as the action NN. the cost …

A Cross Layer Approach To The Novel Distributed Scheduling Protocol And Event-Triggered Controller Design For Cyber Physical Systems, Hao Xu, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In Cyber Physical Systems (CPS), multiple real-time dynamic systems are connected to their corresponding controllers through a shared communication network in contrast with a dedicated line. for such CPS, the existing scheduling schemes for instance Centralized or Distributed Scheduling schemes are unsuitable since the behavior of real-time dynamic systems is ignored during the network protocol design. Therefore, in this paper, a novel distributed scheduling protocol design via cross-layer approach is proposed to optimize the performance of CPS by maximizing the utility function which is generated by using the information collected from both the application and network layers. Subsequently, a novel …

Video Compressive Sensing With 3-D Wavelet And 3-D Noiselet, Dao Lam, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

A new compressive video sampling method is investigated. as opposed to other video sampling methods for which processing is conducted on a single-frame basis, this method is applied on multiple frames of the video stream. by exploiting the extension of Wavelet to 3-D with the support of Noiselet 3-D and combining it with fast reconstruction algorithms, this framework produces successful results quickly while maintaining the quality of the video stream. Despite its simplicity, this new approach outperforms other sophisticated methods. © 2012 IEEE.

Model Based Diagnostics And Prognostics Of Three-Phase Induction Motor For Vapor Compressor Applications, Raja Sekhar Kraleti, Maciej Jan Zawodniok, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this work, a novel scheme for detection and prediction of multiple simultaneous faults in a three-phase induction motor in the context of vapor compression applications is presented. Induction motors used in vapor compression systems operate under variable speed conditions with variable frequencies. Such dynamic operating conditions may cause an occurrence of multiple, simultaneous faults including insulation degradation and a rotor bar breakage. These faults, when left undetected, lead to the failure of the motor and the entire vapor compression system. Hence, a condition monitoring of induction motors is essential. Conventional fault detection methods have various drawbacks including high implementation …

A New Data Aggregation Scheme Via Adaptive Compression For Wireless Sensor Networks, Priya Kasirajan, Carl Larsen, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

Data aggregation is necessary for extending the network lifetime of wireless sensor nodes with limited processing and power capabilities, since energy expended in transmitting a single data bit would be at least several orders of magnitude higher when compared to that needed for a 32-bit computation. Therefore, in this article, a novel nonlinear adaptive pulse coded modulation-Based compression (NADPCMC) scheme is proposed for data aggregation in a wireless sensor network (WSN). the NADPCMC comprises of two estimators-one at the source or transmitter and the second one at the destination node. the estimator at the source node approximates the data value …

Temporal Data Mining Of Uncertain Water Reservoir Data, Abhinaya Mohan, Peter Revesz

School of Computing: Conference and Workshop Papers

This paper describes the challenges of data mining uncertain water reservoir data based on past human operations in order to learn from them reservoir policies that can be automated for the future operation of the water reservoirs. Records of human operations of water reservoirs often contain uncertain data. For example, the recorded amounts of water released and retained in the water reservoirs are typically uncertain, i.e., they are bounded by some minimum and maximum values. Moreover, the time of release is also uncertain, i.e., typically only monthly or weekly amounts are recorded. To increase the effectiveness of data mining of …

[Accepted Article Manuscript Version (Postprint)] Track Me To Track Us: Leveraging Short Range Wireless Technologies For Enabling Energy Efficient Wi-Fi-Based Localization, Mohamed Abdellatif, Abderrahmen Mtibaa, Khaled Harras

Computer Science Faculty Works

Given the success of outdoor tracking via GPS and the rise of real-time context-aware services, users will soon rely on applications that require higher granularity indoor localization. This need is further manifested in countries like Qatar, where various social and business activities occur indoors. Wi-Fi-based indoor localization is one of the most researched techniques due to its ubiquitous deployment and acceptable accuracy for a wide range of applications. However, we do not witness such techniques widely deployed mainly due to their high demand on energy, which is a precious commodity in mobile devices. We propose an energy-efficient indoor localization system …

Adaptive Dynamic Programming-Based State Quantized Networked Control System Without Value And/Or Policy Iterations, Qiming Zhao, Hao Xu, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, the Bellman equation is used to solve the stochastic optimal control of unknown linear discrete-time system with communication imperfections including random delays, packet losses and quantization. a dynamic quantizer for the sensor measurements is proposed which essentially provides system states to the controller. to eliminate the effect of the quantization error, the dynamics of the quantization error bound and an update law for tuning its range are derived. Subsequently, by using adaptive dynamic programming technique, the infinite horizon optimal regulation of the uncertain NCS is solved in a forward-in-time manner without using value and/or policy iterations by …

A Decentralized Fault Detection And Prediction Scheme For Nonlinear Interconnected Continuous-Time Systems, Hasan Ferdowsi, Deepthi L. Raja, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

Complex nonlinear systems such as an aircraft, trains, automobiles, power plants and chemical plants are represented as nonlinear interconnected subsystems. Therefore, in this paper a novel decentralized fault diagnosis and prognosis (FDP) methodology is proposed for such large-scale systems. Current FDP approaches require the knowledge of the entire state or its estimated vector. But the main goal in this work is to design a local fault detector (LFD) or observer for each subsystem based on the measured local states of the subsystem alone. a local residual signal is generated via the measured states of the local subsystem and the estimated …

Influence Of The Listening Context On The Perceived Realism Of Binaural Recordings, Davide Andrea Mauro, Francesco Vitale

Computer Sciences and Electrical Engineering Faculty Research

Binaural recordings and audio are becoming an interesting resource for composers, live performances and augmented reality. This paper focuses on the acceptance and the perceived quality by the audience of such spatial recordings. We present the results of a preliminary study of psychoacoustic perception where N=26 listeners had to report on the realism and the quality of different couples of sounds taken from two different rooms with peculiar reverb. Sounds are recorded with a self-made dummy head. The stimuli are grouped into classes with respects to some characteristics highlighted as potentially important for the task. Listening condition is fixed with …

Identifying And Attributing Similar Traces With Greatest Common Factor Analysis, Fred Cohen

Journal of Digital Forensics, Security and Law

This paper presents an algorithm for comparing large numbers of traces to each other and identifying and presenting groups of traces with similar features. It is applied to forensic analysis in which groups of similar traces are automatically identified and presented so that attribution and other related claims may be asserted, and independently confirmed or refuted. The approach of this paper is to identify an approximate algorithm that will find a large subset of greatest common factor similar groups of arbitrary factors in far less time and space than an exact algorithm using examiner-provided selection criteria for factor definition.

Adaptive Security-Aware Scheduling For Packet Switched Networks Using Real-Time Multi-Agent Systems, Ma'en Saleh Saleh

Dissertations

Conventional real-time scheduling algorithms are in care of timing constraints; they don’t pay any attention to enhance or optimize the real-time packet’s security performance. In this work, we propose an adaptive security-aware scheduling with congestion control mechanism for packet switching networks using real-time agentbased systems. The proposed system combines the functionality of real-time scheduling with the security service enhancement, where the real-time scheduling unit uses the differentiated-earliest-deadline-first (Diff-EDF) scheduler, while the security service enhancement scheme adopts a congestion control mechanism based on a resource estimation methodology.

The security service enhancement unit was designed based on two models: singlelayer and weighted …

Digital Evidence Education In Schools Of Law, Aaron Alva, Barbara Endicott-Popovsky

Annual ADFSL Conference on Digital Forensics, Security and Law

An examination of State of Connecticut v. Julie Amero provides insight into how a general lack of understanding of digital evidence can cause an innocent defendant to be wrongfully convicted. By contrast, the 101-page opinion in Lorraine v. Markel American Insurance Co. provides legal precedence and a detailed consideration for the admission of digital evidence. An analysis of both cases leads the authors to recommend additions to Law School curricula designed to raise the awareness of the legal community to ensure such travesties of justice, as in the Amero case, don’t occur in the future. Work underway at the University …

A Case Study Of The Challenges Of Cyber Forensics Analysis Of Digital Evidence In A Child Pornography Trial, Richard Boddington

Annual ADFSL Conference on Digital Forensics, Security and Law

Perfunctory case analysis, lack of evidence validation, and an inability or unwillingness to present understandable analysis reports adversely affect the outcome course of legal trials reliant on digital evidence. These issues have serious consequences for defendants facing heavy penalties or imprisonment yet expect their defence counsel to have clear understanding of the evidence. Poorly reasoned, validated and presented digital evidence can result in conviction of the innocent as well as acquittal of the guilty. A possession of child pornography Case Study highlights the issues that appear to plague case analysis and presentation of digital evidence relied on in these odious …

After Five Years Of E-Discovery Missteps: Sanctions Or Safe Harbor?, Milton Luoma, Vicki Luoma

Annual ADFSL Conference on Digital Forensics, Security and Law

In 2003 the Zubulake case became the catalyst of change in the world of e-discovery. In that case Judge Shira Scheindlin of the United States District Court for the Southern District of New York set guidelines for e-discovery that served as the basis for amending the Federal Rules of Civil Procedure (FRCP) in December 2006. The amendments incorporated a number of concepts that were described by Judge Scheindlin in the Zubulake case. ( Zubulake v. UBS Warburg LLC, 2003) Since the Zubulake case and the FRCP amendments, numerous cases have interpreted these rules changes, but one of the main points …

Multi-Parameter Sensitivity Analysis Of A Bayesian Network From A Digital Forensic Investigation, Richard E. Overill, Echo P. Zhang, Kam-Pui Chow

Annual ADFSL Conference on Digital Forensics, Security and Law

A multi-parameter sensitivity analysis of a Bayesian network (BN) used in the digital forensic investigation of the Yahoo! email case has been performed using the principle of ‘steepest gradient’ in the parameter space of the conditional probabilities. This procedure delivers a more reliable result for the dependence of the posterior probability of the BN on the values used to populate the conditional probability tables (CPTs) of the BN. As such, this work extends our previous studies using singleparameter sensitivity analyses of BNs, with the overall aim of more deeply understanding the indicative use of BNs within the digital forensic and …