Computer Sciences Commons^™

Expression Profiling Of Human Donor Lungs To Understand Primary Graft Dysfunction After Lung Transplantation, Monika Ray, Sekhar Dharmarajan, Johannes Freudenberg, Weixiong Zhang, Alexander G. Patterson

All Computer Science and Engineering Research

Lung transplantation is the treatment of choice for end-stage pulmonary diseases. A limited donor supply has resulted in 4000 patients on the waiting list. Currently, 10-20% of donor organs offered for transplantation are deemed suitable under the selection criteria, of which 15-25% fails due to primary graft dysfunction (PGD). This has resulted in increased efforts to search for alternative donor lungs selection criteria. In this study, we attempt to further our understanding of PGD by observing the changes in gene expression across donor lungs that developed PGD versus those that did not. Our second goal is to use a machine …

A Fingerspelling Sign Language Visualization , Carol S. Brickman

All Computer Science and Engineering Research

The goal of the Fingerspell Visualization Project is to research methods to improve learning of reading skills through sign language. The techniques are centered on Fingerspelling as the method to bridge stages of skill development. Visualization of a string of text in images of a hand performing the letters of the alphabet in standardized fingerspell sign language positions provide Full Motion Learning as opposed to learning from single pictures.

Combined Controllers That Follow Imperfect Input Motions For Humanoid Robots, Gazihan Alankus, Burchan O. Bayazit

All Computer Science and Engineering Research

Humanoid robots have the potential to become a part of everyday life as their hardware and software challenges are being solved. In this paper we present a system that gets as input a motion trajectory in the form of motion capture data, and produces a controller that controls a humanoid robot in real-time to achieve a motion trajectory that is similar to the input motion data. The controller expects the input motion data not to be dynamically feasible for the robot and employs a combined controller with corrective components to keep the robot balanced while following the motion. Since the …

Byzantine Fault-Tolerant Web Services For N-Tier And Service Oriented Architectures, Sajeeva L. Pallemulle, Kenneth J. Goldman

All Computer Science and Engineering Research

Web Services that provide mission-critical functionality must be replicated to guarantee correct execution and high availability in spite of arbitrary (Byzantine) faults. Existing approaches for Byzantine fault-tolerant execution of Web Services are inadequate to guarantee correct execution due to several major limitations. Some approaches do not support interoperability between replicated Web Services. Other approaches do not provide fault isolation guarantees that are strong enough to prevent cascading failures across organizational and application boundaries. Moreover, existing approaches place impractical limitations on application development by not supporting long-running active threads of computation, fully asynchronous communication, and access to host specific information. We …

Efficient Fair Algorithms For Message Communication, Sergey Gorinsky, Eric J. Friedman, Shane Henderson, Christoph Jechlitschek

All Computer Science and Engineering Research

A computer network serves distributed applications by communicating messages between their remote ends. Many such applications desire minimal delay for their messages. Beside this efficiency objective, allocation of the network capacity is also subject to the fairness constraint of not shutting off communication for any individual message. Processor Sharing (PS) is a de facto standard of fairness but provides significantly higher average delay than Shortest Remaining Processing Time (SRPT), which is an optimally efficient but unfair algorithm. In this paper, we explore efficient fair algorithms for message communication where fairness means that no message is delivered later than under PS. …

A Critical Review On Electromagnetic Precursors And Earthquake Prediction, Levent Sevgi̇

Turkish Journal of Electrical Engineering and Computer Sciences

Seismo-electromagnetic precursory-based earthquake prediction studies are criticized in terms of their scientific content, problem complexity, signal excitation and propagation, causal relations with earthquakes, and public awareness and expectations. One aim is to trigger a new debate on this hot topic in the Electromagnetic Society.

A Variable Gain Pi Controller Used For Speed Control Of A Direct Torque Neuro Fuzzy Controlled Induction Machine Drive, A. Miloudi, Eid A. Al-Radadi, Azeddine Draou

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents an original variable gain PI (VGPI) controller for speed control of a direct torque neuro fuzzy controlled (DTNFC) induction motor drive. First, a VGPI speed controller is designed to replace the classical PI controller in a conventional direct torque controlled induction motor drive. Its simulated performances are then compared to those of a classical PI controller. Then, a direct torque neuro fuzzy control (DTNFC) for a voltage source PWM inverter fed induction motor drive is presented. This control scheme uses the stator flux amplitude and the electromagnetic torque errors through an adaptive NF inference system (ANFIS) to …

New Method For Investigation Of Dynamic Parameters Of Thermoelectric Modules, Raşi̇t Ahiska

Turkish Journal of Electrical Engineering and Computer Sciences

Precise calculation of parameters of thermoelectric modules and thermoelectric devices under operating conditions by present methods is very difficult. In this study, a new method is developed to calculate all parameters of thermoelectric modules. This new method makes it possible to determine the dynamic parameters of a real thermoelectric module operated under different working regimes. Measurement of thermoemf created by an operating module is the basis of this new method. An unloaded thermoelectric module, whose dynamic output parameters are necessary in the design of a medical helmet for the cooling of brain, has been investigated using this new method. A …

Data Mining And Costas Arrays, Konstantinos Drakakis

Turkish Journal of Electrical Engineering and Computer Sciences

Costas arrays are used in RADAR (and SONAR) engineering to represent frequency-hopping patterns that optimize the RADAR's performance. In this work, using all available Costas arrays up to and including order 26, as well as data mining techniques, we investigate how the Costas property and the balance of signs in the difference triangle of a permutation are related. Our conclusion is that there is sufficient evidence to believe that the mechanism responsible for the formation of Costas arrays changes from low to high orders.

Offline Signature Verification Using Graph Matching, Ibrahim S. I. Abuhaiba

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we present a simple and effective signature verification method that depends only on the raw binary pixel intensities and avoids using complex sets of features. The method looks at the signature verification problem as a graph matching problem. The method is tested using genuine and forgery signatures produced by five subjects. An equal error rate of 26.7% and 5.6% was achieved for skilled and random forgeries, respectively. A positive property of our algorithm is that the false acceptance rate of random forgeries vanishes at the point of equal false rejection and skilled forgery false acceptance rates. Keeping …

Umts-Hsdpa In High Altitude Platforms (Haps) Communications, Bazil Taha Ahmed, Miguel Calvo Ramon, Leandro De Haro-Ariet

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, the performance of HAPs (High Altitudes Platforms) UMTS HSDPA (High Speed Downlink Packet Access) is studied for different HAPs height h, different cells radius R and two directions (0° and 30°) within the cell. The network under study is assumed to have 61 ground cells. It is noticed that, for urban zone users, the effective range is lower than the effective range for users in rural zones for a given modulation scheme. Also it is noticed that in rural zone, the HSDPA can support higher modulation schemes. It is noticed that, when 80% of the base station …

A Review Of Studies In Swarm Robotics, Levent Bayindir, Erol Şahi̇n

Turkish Journal of Electrical Engineering and Computer Sciences

Swarm robotics is a new approach to the coordination of large numbers of relatively simple robots. The approach takes its inspiration from the system-level functioning of social insects which demonstrate three desired characteristics for multi-robot systems: robustness, flexibility and scalability. In this paper we have presented a preliminary taxonomy for swarm robotics and classified existing studies into this taxonomy after investigating the existing surveys related to swarm robotics literature. Our parent taxonomic units are modeling, behavior design, communication, analytical studies and problems. We are classifying existing studies into these main axes. Since existing reviews do not have enough number of …

Aggregation, Foraging, And Formation Control Of Swarms With Non-Holonomic Agents Using Potential Functions And Sliding Mode Techniques, Veysel Gazi̇, Bariş Fi̇dan, Y. Si̇nan Hanay, İlter Köksal

Turkish Journal of Electrical Engineering and Computer Sciences

In this article we consider the aggregation, foraging, and formation control of swarms whose agents are moving in 2-dimensions with non-holonomic unicycle agent dynamics. We approach these problems using artificial potentials and sliding mode control. The main contribution is extension of the recent results (mainly for aggregation) in the literature based on a similar approach for simple integrator agent dynamics models to a significantly more realistic and more difficult setting with non-holonomic unicycle agent dynamics models. In particular, we design continuous-time control schemes via a constructive analysis based on artificial potential functions and sliding mode control techniques. The effectiveness of …

Using Angle Of Arrival (Bearing) Information For Localization In Robot Networks, Tolga Eren

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we consider using angle of arrival information (bearing) for localization in robot networks. The essential property we require in this paper is that a node can infer heading information from its neighbors. We address the uniqueness of network localization solutions by the theory of globally rigid graphs. We show that while the parallel rigidity problem for formations with bearings is isomorphic to the distance case, the global rigidity of the formation is simpler (in fact identical to the simpler rigidity case) for a network with bearings, compared to formations with distances. We provide the conditions of localization …

Aggregation In Swarm Robotic Systems: Evolution And Probabilistic Control, Onur Soysal, Erki̇n Bahçeci̇, Erol Şahi̇n

Turkish Journal of Electrical Engineering and Computer Sciences

In this study we investigate two approachees for aggregation behavior in swarm robotics systems: Evolutionary methods and probabilistic control. In first part, aggregation behavior is chosen as a case, where performance and scalability of aggregation behaviors of perceptron controllers that are evolved for a simulated swarm robotic system are systematically studied with different parameter settings. Using a cluster of computers to run simulations in parallel, four experiments are conducted varying some of the parameters. Rules of thumb are derived, which can be of guidance to the use of evolutionary methods to generate other swarm robotic behaviors as well. In the …

Swarm Robot Systems Based On The Evolution Of Personality Traits, Sidney Nascimento Givigi Jr.

Turkish Journal of Electrical Engineering and Computer Sciences

Game theory may be very useful in modeling and analyzing swarms of robots. Using game theory in conjunction with traits of personalities, we achieve intelligent swarm robots. Traits of personality are characteristics of each robot that define the robots' behaviours. The environment is represented as a game and due to the evolution of the traits through a learning process, we show how the robots may react intelligently to changes in the environment. A proof of convergence for the proposed algorithm is offered. The process of selection of traits is discussed and the potential of the modeling is demonstrated in several …

Design And Implementation Of An Ad-Hoc Routing Protocol For Mobile Robots, Carlos Agüero, Jose M. Canas, Miguel Ortu˜No, Vicente Matellan

Turkish Journal of Electrical Engineering and Computer Sciences

Mobile robots need to be able to communicate among themselves, as well as with hosts participating in the task that they are all involved in. Wired networks are obviously not suitable for mobile robots. Current wireless networks based on a fixed infrastructure (GSM, WiFi, etc.) to route packets may not be suitable because this infrastructure does not cover every place and the requirements of its resources. The best choice for mobile robots are Ad-Hoc networks, which are wireless and do not need a fixed infrastructure. This article describes PERA, a complete communications library including link, net, and transport layers for …

Optimal Location For Shunt Connected Facts Devices In A Series Compensated Long Transmission Line, P.R. Sharma, Ashok Kumar, Narender Kumar

Turkish Journal of Electrical Engineering and Computer Sciences

Shunt FACTS devices are used for controlling transmission voltage, power flow, reducing reactive losses, and damping of power system oscillations for high power transfer levels. In this paper the optimal location of a shunt FACT device is investigated for an actual line model of a transmission line having series compensation at the center. Effect of change in degree of series compensation on the optimal location of the shunt FACTS device to get the highest possible benefit is studied. It is found that the optimal location of the shunt FACTS device varies with the change in the level of series compensation …

A New Relaying Algorithm To Detect Loss Of Excitation Of Synchronous Generators, Ömer Usta, M. H. Musa, M. Bayrak, M.A. Redfern

Turkish Journal of Electrical Engineering and Computer Sciences

A new digital relaying algorithm is introduced for the protection of synchronous generators against loss of excitation conditions. The new algorithm is based on measuring of the 3-phase reactive power output of the machines, and monitors the direction and magnitude of leading reactive power at the generator terminal. The protection algorithm is designed such that it can provide reliable protection against loss of field conditions and remains stable during recoverable power system swing conditions. While the new relay produces a trip signal for partial loss of field conditions causing the machine to lose its stability, it remains stable for the …

A Sensitive Ann Based Differential Relay For Transformer Protection With Security Against Ct Saturation And Tap Changer Operation, Hassan Khorashadi Zadeh, Zuyi Li

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents an artificial neural network (ANN) based scheme for fault identification in power transformer protection. The proposed scheme is featured by the application of ANN to identifying system patterns, the unique choice of harmonics of positive sequence differential currents as ANN inputs, the effective handling of current transformer (CT) saturation with an ANN based approach, and the consideration of tap changer position for correcting secondary CT current. Performance of the proposed scheme is studied for a wide variety of operating conditions using data generated from simulation. The results indicate that the proposed scheme provides a fast and sensitive …

Study Of The Warranty Cost Model For Software Reliability With An Imperfect Debugging Phenomenon, D.R. Prince Williams

Turkish Journal of Electrical Engineering and Computer Sciences

Software reliability is one of the most important characteristics of software quality. Its measurement and management technologies employed during the software life-cycle are essential for producing and maintaining quality/reliable software systems. Herein, we discuss a modified approach to calculating the delivery cost of a software product, when warranty is to be provided, with an imperfect debugging phenomenon. Unlike existing cost models, here the strategy was to consider maintenance support given to the customer with an imperfect debugging phenomenon. The optimal release time can be calculated for various reliability levels by minimizing the cost. The delivery cost, reliability of the software …

Optimal Layout Of Multicast Groups Using Network Embedded Multicast Security In Ad Hoc Sensor Networks, Richard R. Brooks, Brijesh Pillai, Michele C. Weigle, Matthew Pirretti

Computer Science Faculty Publications

This paper considers the security of sensor network applications. Our approach creates multicast regions that use symmetric key cryptography for communications. Each multicast region contains a single keyserver that is used to perform key management and maintain the integrity of a multicast region. Communications between two multicast regions is performed by nodes that belong to both regions. To ease the network management burden, it is desirable for the networks to self-organize into regions and dynamically select their keyservers. This paper shows how to determine the number of keyservers (k) to use and the size in the number of hops (h) …

Iterated Weaker-Than-Weak Dominance, Shih-Fen Cheng, Michael P. Wellman

Research Collection School Of Computing and Information Systems

We introduce a weakening of standard gametheoretic δ-dominance conditions, called dominance, which enables more aggressive pruning of candidate strategies at the cost of solution accuracy. Equilibria of a game obtained by eliminating a δ-dominated strategy are guaranteed to be approximate equilibria of the original game, with degree of approximation bounded by the dominance parameter. We can apply elimination of δ-dominated strategies iteratively, but the for which a strategy may be eliminated depends on prior eliminations. We discuss implications of this order independence, and propose greedy heuristics for determining a sequence of eliminations to reduce the game as far as possible …

Using Pareto Fronts To Evaluate Polyp Detection Algorithms For Ct Colonography, Adam Huang, Jiang Li, Ronald M. Summers, Nicholas Petrick, Amy K. Hara

Electrical & Computer Engineering Faculty Publications

We evaluate and improve an existing curvature-based region growing algorithm for colonic polyp detection for our CT colonography (CTC) computer-aided detection (CAD) system by using Pareto fronts. The performance of a polyp detection algorithm involves two conflicting objectives, minimizing both false negative (FN) and false positive (FP) detection rates. This problem does not produce a single optimal solution but a set of solutions known as a Pareto front. Any solution in a Pareto front can only outperform other solutions in one of the two competing objectives. Using evolutionary algorithms to find the Pareto fronts for multi-objective optimization problems has been …

Validating Pareto Optimal Operation Parameters Of Polyp Detection Algorithms For Ct Colonography, Jiang Li, Adam Huang, Nicholas Petrick, Jianhua Yao, Ronald M. Summers, Maryellen L. Giger (Ed.), Nico Karssemeijer (Ed.)

Electrical & Computer Engineering Faculty Publications

We evaluated a Pareto front-based multi-objective evolutionary algorithm for optimizing our CT colonography (CTC) computer-aided detection (CAD) system. The system identifies colonic polyps based on curvature and volumetric based features, where a set of thresholds for these features was optimized by the evolutionary algorithm. We utilized a two-fold cross-validation (CV) method to test if the optimized thresholds can be generalized to new data sets. We performed the CV method on 133 patients; each patient had a prone and a supine scan. There were 103 colonoscopically confirmed polyps resulting in 188 positive detections in CTC reading from either the prone or …

Development And Implementation Of Optimized Energy-Delay Sub-Network Routing Protocol For Wireless Sensor Networks, James W. Fonda, Maciej Zawodniok, S. Jagannathan, Steve E. Watkins

Electrical and Computer Engineering Faculty Research & Creative Works

The development and implementation of the optimized energy-delay sub-network routing (OEDSR) protocol for wireless sensor networks (WSN) is presented. This on demand routing protocol minimizes a novel link cost factor which is defined using available energy, end-to-end (E2E) delay and distance from a node to the base station (BS), along with clustering, to effectively route information to the BS. Initially, the nodes are either in idle or sleep mode, but once an event is detected, the nodes near the event become active and start forming sub-networks. Formation of the inactive network into a sub-network saves energy because only a portion …

A Fuzzy Logic Controller For Autonomous Wheeled Vehicles, Mohamed Trabia, Linda Z. Shi, Neil Eugene Hodge

Mechanical Engineering Faculty Research

Autonomous vehicles have potential applications in many fields, such as replacing humans in hazardous environments, conducting military missions, and performing routine tasks for industry. Driving ground vehicles is an area where human performance has proven to be reliable. Drivers typically respond quickly to sudden changes in their environment. While other control techniques may be used to control a vehicle, fuzzy logic has certain advantages in this area; one of them is its ability to incorporate human knowledge and experience, via language, into relationships among the given quantities. Fuzzy logic controllers for autonomous vehicles have been successfully applied to address various …

Supply Chain Information Sharing In A Macro Prediction Market, Zhiling Guo, Fang Fang, Andrew B. Whinston

Research Collection School Of Computing and Information Systems

This paper aims to address supply chain partners' incentives for information sharing from an information systems design perspective. Specifically, we consider a supply chain characterized by N geographically distributed retailers who order a homogeneous product from one manufacturer. Each retailer's demand risk consists of two parts: a systematic risk part that affects all retailers and an idiosyncratic risk part that only has a local effect. We propose a macro prediction market to effectively elicit and aggregate useful information about systematic demand risk. We show that such information can be used to achieve accurate demand forecast sharing and better channel coordination …

Cosign: A Parallel Algorithm For Coordinated Traffic Signal Control, Shih-Fen Cheng, Marina A. Epelman, Robert L. Smith

Research Collection School Of Computing and Information Systems

The problem of finding optimal coordinated signal timing plans for a large number of traffic signals is a challenging problem because of the exponential growth in the number of joint timing plans that need to be explored as the network size grows. In this paper, the game-theoretic paradigm of fictitious play to iteratively search for a coordinated signal timing plan is employed, which improves a system-wide performance criterion for a traffic network. The algorithm is robustly scalable to realistic-size networks modeled with high-fidelity simulations. Results of a case study for the city of Troy, MI, where there are 75 signalized …

Gridfields: Model-Driven Data Transformation In The Physical Sciences, Bill Howe

Dissertations and Theses

Scientists' ability to generate and store simulation results is outpacing their ability to analyze them via ad hoc programs. We observe that these programs exhibit an algebraic structure that can be used to facilitate reasoning and improve performance. In this dissertation, we present a formal data model that exposes this algebraic structure, then implement the model, evaluate it, and use it to express, optimize, and reason about data transformations in a variety of scientific domains.

Simulation results are defined over a logical grid structure that allows a continuous domain to be represented discretely in the computer. Existing approaches for manipulating …