Computer Engineering Commons^™

Design Of An Extensible Network Testbed With Heterogeneous Components, Charlie Wisemen, Jyoti Parwatikar, Ken Wong, John Dehart, Jonathan Turner

All Computer Science and Engineering Research

Virtualized network infrastructures are currently deployed in both research and commercial contexts. The complexity of the virtualization layer varies greatly in different deployments, ranging from cloud computing environments, to carrier Ethernet applications using stacked VLANs, to networking testbeds. In all of these cases, there are many users sharing the resources of one provider, where each user expects their resources to be isolated from all other users. Our work in this area is focused on network testbeds. In particular, we present the design of the latest version of the Open Network Laboratory (ONL) testbed. This redesign generalizes the underlying infrastructure to …

Self-Stabilizing Computation Of 3-Edge-Connected Components, Abusayeed Saifullah, Yung Tsin

All Computer Science and Engineering Research

No abstract provided.

Non-Programmers Identifying Functionality In Unfamiliar Code: Strategies And Barriers, Paul Gross, Caitlin Kelleher

All Computer Science and Engineering Research

Source code on the web is a widely available and potentially rich learning resource for non-programmers. However, unfamiliar code can be daunting to end-users without programming experience. This paper describes the results of an exploratory study in which we asked non-programmers to find and modify the code responsible for specific functionality within unfamiliar programs. We present two interacting models of how non-programmers approach this problem: the Task Process Model and the Landmark-Mapping model. Using these models, we describe code search strategies non-programmers employed and the difficulties they encountered. Finally, we propose guidelines for future programming environments that support non-programmers in …

Adaptive Service Provisioning For Wireless Sensor Networks, Chien-Liang Fok, Gruia-Catalin Roman, Chenyang Lu

All Computer Science and Engineering Research

Service provisioning has gained significant attention as a promising programming model for heterogeneous wireless sensor networks. Its key idea is to exploit the decoupling of service providers and consumers to enable platform-independent applications that are dynamically bound to platform-specific services. We explore novel adaptive service binding strategies that are able to cope with network dynamics and to promote energy conservation. To achieve this goal, we developed policies and algorithms that automatically switch providers in response to network topology changes and adapt application behavior when opportunities for energy savings surface. The latter is accomplished by providing limited information about the energy …

Performance-Engineered Network Overlays For High Quality Interaction In Virtual Worlds, Mart Haitjema, Ritun Patney, Jon Turner, Charlie Wiseman, John Dehart

All Computer Science and Engineering Research

Overlay hosting systems such as PlanetLab, and cloud computing environments such as Amazon’s EC2, provide shared infrastructures within which new applications can be developed and deployed on a global scale. This paper ex-plores how systems of this sort can be used to enable ad-vanced network services and sophisticated applications that use those services to enhance performance and provide a high quality user experience. Specifically, we investigate how advanced overlay hosting environments can be used to provide network services that enable scalable virtual world applications and other large-scale distributed applications requiring consistent, real-time performance. We propose a novel network architecture called …

Reliable Patient Monitoring: A Clinical Study In A Step-Down Hospital Unit, Octav Chipara, Chenyang Lu, Thomas C. Bailey, Gruia-Catalin Roman

All Computer Science and Engineering Research

This paper presents the design, deployment, and empirical study of a wireless clinical monitoring system that collects pulse and oxygen saturation readings from patients. The primary contribution of this paper is an in-depth clinical trial that assesses the feasibility of wireless sensor networks for patient monitoring in general (non-ICU) hospital units. The trial involved 32 patients monitored in a step-down cardiology unit at Barnes-Jewish Hospital, St. Louis. During a total of 31 days of monitoring, the network achieved high reliability (median 99.92%, range 95.21% - 100%). The overall reliability of the system was dominated by sensing reliability (median 80.55%, range …

Achieving Coordination Through Dynamic Construction Of Open Workflows, Louis Thomas, Justin Wilson, Grui-Catalin Roman, Christopher Gill

All Computer Science and Engineering Research

Workflow middleware executes tasks orchestrated by rules defined in a carefully handcrafted static graph. Workflow management systems have proved effective for service-oriented business automation in stable, wired infrastructures. We introduce a radically new paradigm for workflow construction and execution called open workflow to support goal-directed coordination among physically mobile people and devices that form a transient community over an ad hoc wireless network. The quintessential feature of the open workflow paradigm is dynamic construction of custom, context-specific workflows in response to unpredictable and evolving circumstances by exploiting the knowledge and services available within a given spatiotemporal context. This paper introduces …

Globally Clocked Magnetic Logic Circuits, Michael Hall, Albrecht Jander, Roger D. Chamberlain, Pallavi Dhagat

All Computer Science and Engineering Research

Magnetic spin valve devices enable the design of logic and memory elements that are suitable for use when constructing digital systems. A master-slave flip-flop design is proposed that can be clocked using an externally applied global magnetic field. With an external global clock, the digital system no longer needs to deliver the clock on-chip, thereby eliminating the need for a clock distribution network. We assess the power, area, and speed implications associated with the ability to eliminate the clock distribution network on a hybrid CMOS-magnetologic digital system.

Radio Mapping For Indoor Environments, Octav Chipara, Gregory Hackmann, Chenyang Lu, William D. Smart

All Computer Science and Engineering Research

The efficient deployment and robust operation of many sensor network applications depend on deploying relays to ensure wireless coverage. Radio mapping aims to predict network coverage based on a small number of link measurements from sampled locations. Radio mapping is particularly challenging in complex indoor environments where walls significantly affect radio signal propagation. This paper makes the following key contributions to indoor radio mapping. First, our empirical study in an office building identifies a wall-classification model as the most effective model for indoor environments due to its balance between model complexity and accuracy. Second, we propose a practical algorithm to …

Modelling Situation Awareness For Context‐Aware Decision Support, Yu-Hong Feng, Teck-Hou Teng, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

Situation awareness modelling is popularly used in the command and control domain for situation assessment and decision support. However, situation models in real-world applications are typically complex and not easy to use. This paper presents a Context-aware Decision Support (CaDS) system, which consists of a situation model for shared situation awareness modelling and a group of entity agents, one for each individual user, for focused and customized decision support. By incorporating a rule-based inference engine, the entity agents provide functions including event classification, action recommendation, and proactive decision making. The implementation and the performance of the proposed system are demonstrated …

Insulation Condition Assessment Of Power Transformers Using Accelerated Ageing Tests, Mohammad Mirzaie, Ahmad Gholami, Hamid Reza Tayebi

Turkish Journal of Electrical Engineering and Computer Sciences

Thermal stress due to losses and environment temperature causes degradation to paper/oil insulation systems in transformers, even at operating temperature. Experience indicates that thermal ageing of oil and paper in power transformers leads to the change of some insulation characteristics. In this paper, insulating papers immersed in oil have been acceleratory aged at 140, 150, and 160 °C under laboratory conditions. Some of the oil properties, such as water content, breakdown voltage, acidity, together with the aged insulating paper properties such as electric strength, dielectric dissipation factor and tensile strength were measured and analyzed. Also, insulation system conditions under thermal …

Accurate Prediction Of Crosstalk For Rc Interconnects, Selahatti̇n Sayil, Merlyn Rudrapati

Turkish Journal of Electrical Engineering and Computer Sciences

This work proposes an accurate crosstalk noise estimation method in the presence of multiple RC lines for use in design automation tools. The method correctly models the loading effects of non switching aggressors and aggressor tree branches using resistive shielding effect and realistic exponential input waveform. Noise peak and width expressions derived show very good results in comparison to HSPICE results. Results show that average error for noise peak is 4.1% and for the width is 6.8% while allowing for very fast analysis.

Softcomputing Identification Techniques Of Asynchronous Machine Parameters: Evolutionary Strategy And Chemotaxis Algorithm, Nouri Benaïdja

Turkish Journal of Electrical Engineering and Computer Sciences

Softcomputing techniques are receiving attention as optimisation techniques for many industrial applications. Although these techniques eliminate the need for derivatives computation, they require much work to adjust their parameters at the stage of research and development. Issues such as speed, stability, and parameters convergence remain much to be investigated. This paper discusses the application of the method of reference model to determine parameters of asynchronous machines using two optimisation techniques. Softcomputing techniques used in this paper are evolutionary strategy and the chemotaxis algorithm. Identification results using the two techniques are presented and compared with respect to the conventional simplex technique …

Parameter Identification Of A Separately Excited Dc Motor Via Inverse Problem Methodology, Mounir Hadef, Mohamed Rachid Mekideche

Turkish Journal of Electrical Engineering and Computer Sciences

Identification is considered to be among the main applications of inverse theory and its objective for a given physical system is to use data which is easily observable, to infer some of the geometric parameters which are not directly observable. In this paper, a parameter identification method using inverse problem methodology is proposed. The minimisation of the objective function with respect to the desired vector of design parameters is the most important procedure in solving the inverse problem. The conjugate gradient method is used to determine the unknown parameters, and Tikhonov's regularization method is then used to replace the original …

Pca Based Protection Algorithm For Transformer Internal Faults, Erdal Kiliç, Okan Özgönenel, Ömer Usta, Dave Thomas

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper a new protection scheme is introduced to detect and identify transformer winding faults. The new approach is based on artificial neural networks (ANNs) using radial basis functions (RBFs) and the principal component analysis (PCA). The nonlinear system's input and output data is manipulated without considering any model of the system. This approach is used to detect and identify internal short circuit faults of a three phase custom built transformer. The suggested technique is also able to distinguish between the fault and magnetizing inrush current. The test studies carried out shows that the proposed method leads to satisfactory …

Polymorphic Worm Detection Using Strong Token-Pair Signatures, Burak Bayoğlu, İbrahi̇m Soğukpinar

Turkish Journal of Electrical Engineering and Computer Sciences

Malicious software has become a big threat to information systems, which are widely used to store, transfer and process information for many critical assets. Worms are one of the most harmful network-enabled malicious software that can threaten networks and applications. Two main characteristics of worms distinguish them from the well-known virus programs and as a result are much more dangerous than the virus programs. First, they do not need to attach themselves to an existing program. Second, worms do not require end-user interaction to realize the intended attack. Therefore, a large number of victims can be infected in a short …

An Intelligent Face Features Generation System From Fingerprints, Şeref Sağiroğlu, Necla Özkaya

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a novel intelligent system based on artificial neural networks was designed and introduced for generating faces from fingerprints with high accuracy. The proposed system has a number of modules including two feature enrolment modules for acquiring the fingerprints and faces into the system, two feature extractors for extracting the feature sets of fingerprint and face biometrics, an artificial neural network module that was configured with the help of Taguchi experimental design method for establishing relationships among the biometric features, a face re-constructor for building up face features from the results of the system, and a test module …

Cdm Based Controller Design For Nonlinear Heat Exchanger Process, Erkan İmal

Turkish Journal of Electrical Engineering and Computer Sciences

Most processes are nonlinear, and their control is a difficult yet important problem. The heat exchanger is an example onesuch nonlinear process. In the present paper, the effect of process nonlinearity on the performance of set point tracking and disturbance rejection in two controller methods is investigated. Initially, afirst order plus dead time (FOPDT) model of the process is obtainedvia a software known as Loop-Pro Trainer. Then, the PI-controller tuning values are computed using the internal model control (IMC) correlations based on truncated (first-order) Taylor series approximation. Next, another controller is designed using the coefficient diagram method (CDM). Finally, the …

Variance And Kurtosis-Based Characterization Of Resonances In Stochastic Transmission Lines: Local Versus Global Random Geometries, Ousmane Sy, Martijn Van Beurden, Bastiaan Michielsen, Antonius Tijhuis

Turkish Journal of Electrical Engineering and Computer Sciences

A stochastic method is proposed to characterize electromagnetic couplings involving geometrically perturbed transmission lines. A combined exploitation of suitably defined statistical tools is presented to appreciate the intensity of the dispersion of response variables both physically via the variance, and statistically through the kurtosis or fourth-order moment. The usefulness of this method to analyze resonances is illustrated by the study of a transmission line affected by two different types of random geometrical perturbations, viz. a local deformation modeled by a wavelet and global sinusoidal undulations.

Weak Penetration And Radiation Through Apertures In Conducting Bodies Of Revolution, Korkut Yeği̇n

Turkish Journal of Electrical Engineering and Computer Sciences

The simplest way to solve for penetration through small apertures in conducting surfaces is to treat the body as a scatterer and determine the interior field as the sum of the incident field and the scattered field contributed by the current induced on the surface of the body. However, it is well known that, if the aperture is very small or if the penetrated field is very weak this method yields very inaccurate results, which, in turn, prohibits proper design of electronic systems, especially for electromagnetic compatibility and interference. Previously, alternative integral equations formulations were proposed to remedy this problem …

Experimantal Characterization And Equivalent Circuit Extraction Of Nanowires For Signal Integrity Applications, Giulio Antonini, Marco Di Clerico, Antonio Orlandi, Vittorio Ricchiuti, Maurizio Passacantando, Sandro Santucci

Turkish Journal of Electrical Engineering and Computer Sciences

This paper illustrates the design steps of a printed circuit board used as test vehicles for the measurement of the electrical properties of carbon nanotube's deposit. The board has been built and used for the measurements. The measured data are post-processed in order to extract the required properties of the only nanotubes. An equivalent circuit is extracted for further use in EDA simulators and the IEEE P1597 Standard is used to compare the results.

Conductive Emi Noise Measurement For Switched Reluctance Drive, Hao Chen, Xiaohui Qiu, Yang Zhao

Turkish Journal of Electrical Engineering and Computer Sciences

The component parts of the tested four-phase Switched Reluctance drive are described with the four-phase 8/6 structure double salient reluctance motor, the four-phase asymmetric bridge power converter and the 89C52 MCU digital controller. The conductive electromagnetic interference noise measurement equipment is described with the function of separated common-mode noise and differential-mode noise. The tested results of common-mode noise and differential-mode noise of the tested Switched Reluctance drive are presented and the tested results of frequency spectrum are given.

Emc Education At The University Of Technology Zurich, Gökhan Apaydin, Ni̇yazi̇ Ari

Turkish Journal of Electrical Engineering and Computer Sciences

This paper illustrates educational issues in electromagnetic compatibility (EMC) engineering in Switzerland and presents the contents of courses and practical materials for EMC education at the University of Technology Zurich. After giving the fundamentals of theoretical part, practical applications have been given to make students and engineers aware of EMC issues and its problems.

Two Dimensional Ebg Structures For Multiband Noise Mitigation, Antonio Orlandi, Antonio Ciccomancini

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper a two dimensional (2D) electromagnetic Bandgap (EBG) structure is proposed for multi band noise mitigation in PWR/GND plane pairs. Excellent noise suppression (-60 dB) is achieved in multiple bands within the range 0--8 GHz with a low start frequency. Because of the 2D EBG, no additional metal layer is required. Signal Integrity analysis is also studied by modelling a microstrip to stripline transition (both single ended and differential) and by evaluating insertion loss, TDR as well as eye diagram.

Development Of A Magnetic Field Model And Insertion~Into A Commercial Electromagnetic Simulator, Priscila Fernandez Lopez, Christian Arcambal, Yolanda Vives Gilabert, Abhishek Ramanujan, David Baudry, Anne Louis, Belahcene Mazari

Turkish Journal of Electrical Engineering and Computer Sciences

To take into account~certain ElectroMagnetic Compatibility (EMC) aspects~and especially to evaluate the magnetic fields radiated by electronic components, different radiated emission models have been created. Within IRSEEM, a magnetic field model based on equivalent sources (electric dipoles) placed on a plane has been developed. Thus, this paper presents the modelling procedure that requires~magnetic near-field measurements and matrix inversion methods. Concerning the measurements of the field radiated by the component under test,~a near-field test bench with a loop antenna is used to~quantify the tangential components of the magnetic field in amplitude and phase. Then, these data are used as input to …

Electromagnetic Compatibility Engineering Education: Problems, Challenges And Perspectives, Levent Sevgi̇

Turkish Journal of Electrical Engineering and Computer Sciences

Education and training problems and challenges in EMC Engineering are discussed. The necessity of physics-based modeling (theory) and hands-on training (practice) are emphasized. An introductory level EMC lecture and a short course outline are given for modern EMC education.

New Esd Standard And Influence On Test Equipment Requirements, Nicholas Wright

Turkish Journal of Electrical Engineering and Computer Sciences

The IEC61000-4 series of standards form a basic framework for the immunity and emissions testing of electrical and electronic equipment. They are the basis for EN standards used to test CE compliance of electrical and electronic products sold within the European Union. After a period of relative stability, changes are being introduced, designed to improve reliable application of the basic standards and ensure that the same results are obtained no matter where the tests are performed. Many changes relate to the calibration procedures for the test equipment. The surge standard, IEC61000-4-5, was revised at Edition 2 to amend impulse performance …

Mathematical Models For Natural Gas Forecasting, Steven Vitullo, Ronald H. Brown, George F. Corliss, Brian M. Marx

Electrical and Computer Engineering Faculty Research and Publications

It is vital for natural gas Local Distribution Companies (LDCs) to forecast their customers' natural gas demand accurately. A significant error on a single very cold day can cost the customers of the LDC millions of dollars. This paper looks at the financial implication of forecasting natural gas, the nature of natural gas forecasting, the factors that impact natural gas consumption, and describes a survey of mathematical techniques and practices used to model natural gas demand. Many of the techniques used in this paper currently are implemented in a software GasDay^TM, which is currently used by 24 LDCs …

A Pilot Study Evaluating Use Of A Computer-Assisted Neurorehabilitation Platform For Upper-Extremity Stroke Assessment, Xin Feng, Jack Winters

Electrical and Computer Engineering Faculty Research and Publications

Background

There is a need to develop cost-effective, sensitive stroke assessment instruments. One approach is examining kinematic measures derived from goal-directed tasks, which can potentially be sensitive to the subtle changes in the stroke rehabilitation process. This paper presents the findings from a pilot study that uses a computer-assisted neurorehabilitation platform, interfaced with a conventional force-reflecting joystick, to examine the assessment capability of the system by various types of goal-directed tasks.

Methods

Both stroke subjects with hemiparesis and able-bodied subjects used the force-reflecting joystick to complete a suite of goal-directed tasks under various task settings. Kinematic metrics, developed for specific …

A Covert Encryption Method For Applications In Electronic Data Interchange, Jonathan Blackledge, Dmitry Dubovitskiy

Articles

A principal weakness of all encryption systems is that the output data can be ‘seen’ to be encrypted. In other words, encrypted data provides a ‘flag’ on the potential value of the information that has been encrypted. In this paper, we provide a new approach to ‘hiding’ encrypted data in a digital image.

In conventional (symmetric) encryption, the plaintext is usually represented as a binary stream and encrypted using an XOR type operation with a binary cipher. The algorithm used is ideally designed to: (i) generate a maximum entropy cipher so that there is no bias with regard to any …