Digital Commons Network^™

Synthesis By Complexation Processes And Characterization Of Lini0.8Co0.2O2 Cathode Materials, Jing Liu, Zhao-Yin Wen, Zhong-Hua Gu, Xiu-Jian Zhu, Zu-Xiang Lin

Journal of Electrochemistry

The layered LiNi_0.8Co_0.2O₂ compound, which has been of great interest for lithium ion batteries, was prepared at low temperatures by calcining a complex precursor at different temperatures. The physical properties of the synthesized cathode materials were discussed in the light of structural (XRD). The charge and discharge cycling of the cells containing the synthesized oxide as the positive electrode in conjunction with lithium metals and employing a non-aqueous electrolyte showed that LiNi_0.8Co_0.2O₂ treated at 900 ℃ exhibited excellent performances. The first discharge capacity of LLiNi_0.8Co_0.2O_{2 …}

Fabrication Of SncuX/Cms Composite Materials For Lithium-Ion Batteries, Yu Liu, Jing-Ying Xie, Jun Yang, Ke Wang, Bao-Feng Wang

Journal of Electrochemistry

The composite material were prepared by sub-ctrochemical cycling tests showed that coulombic efficiency of the electrodes prepared by the composite materials was near 100 % after second cycle and the capacity dropped less than 5% after the 30th cycle, versus 390 mAh⋅g^-1 special capacity, improving 26% special capacity of pure CMS electrode. The electrochemical performance of the composite materials is depended strongly on the alloy content in the composite, the addhesive strength between alloy particles and CMS matrix, the distribution of particles on the surface of CMS and the particle size of alloy. The composite material can be applied …

Fenton Reagent Produced In Electrolysis Cell And Its Using In Degradation And Decolourization Of Dye, Xi Zheng, Ri-Yao Chen, Rui-Fang Lan, Xiao Chen, Zhen Chen

Journal of Electrochemistry

The electro-chemical processing to produce Fenton reagent has been described. Fenton reagent having a high redox potential has been used as an oxidant in treatment of dye wastewater. Results show that both of the degradation and decolourization of dyes are efficient. The decolourization of dye wastewater reaches 100%.The COD removing rate is about 80%.

Satisficing Applied To Simulated Soccer, Jay Packard

Theses and Dissertations

Satisficing was introduced by the economist Herbert Simon to allow for decisions that are "good enough" when there are insufficient computational resources and knowledge to obtain the optimal outcome. Autonomous multi-agent systems often require such decision making because of the complexity and unknown factors present in such an environment. Satisficing has been extended significantly by Wynn Stirling. Through extended satisficing, he has departed from conventional approaches to autonomous multi-agent systems, based as they usually are on the assumption that each participant is motivated exclusively by its own self interest, and will therefore attempt to maximize its benefit, regardless of the …

Index-Matched Boundary Techniques For The Elimination Of Acoustical Resonances, Jack H. Parker, Bradley D. Duncan

Electro-Optics and Photonics Faculty Publications

We extend the principle of optical index of refraction to apply the concept of acoustical index for transverse acoustical wave propagation in strings. The relationship between acoustical index and mass density of the acoustic material is developed. With this theoretical link established, classic index-matching techniques are explored at acoustical boundaries. Proper selection of boundary interface segments leads to the elimination of resonant vibrationalmodes that occur in rigidly supported strings, while maintaining the nonresonant vibration response.

Personality Types In Software Engineering, Luiz Fernando Capretz

Electrical and Computer Engineering Publications

No abstract provided.

Real Time Dynamic Trajectory Smoothing For Uninhabited Aerial Vehicles, Erik Anderson, Randal Beard, Timothy W. Mclain

Faculty Publications

Sponsorship: AFOSR, DARPA. This paper presents a real-time, feasible trajectory generation algorithm for unmanned air vehicles (UAVs) flying through a sequence of waypoints. The algorithm produces extremal trajectories that transition between straight-line path segments in a time-optimal fashion. In addition, the algorithm can be configured so that the dynamically feasible trajectory has the same path length as the straight-line waypoint path. Implementation issues associated with the algorithm are described in detail. Simulation studies show the effectiveness of the proposed method.

Joint Buffer Management And Scheduling For Input Queued Switches, Dequan Liu

Dissertations

Input queued (IQ) switches are highly scalable and they have been the focus of many studies from academia and industry. Many scheduling algorithms have been proposed for IQ switches. However, they do not consider the buffer space requirement inside an IQ switch that may render the scheduling algorithms inefficient in practical applications.

In this dissertation, the Queue Length Proportional (QLP) algorithm is proposed for IQ switches. QLP considers both the buffer management and the scheduling mechanism to obtain the optimal allocation region for both bandwidth and buffer space according to real traffic load. In addition, this dissertation introduces the Queue …

Robust And Efficient Video/Image Transmission, Xi Min Zhang

Dissertations

The Internet has become a primary medium for information transmission. The unreliability of channel conditions, limited channel bandwidth and explosive growth of information transmission requests, however, hinder its further development. Hence, research on robust and efficient delivery of video/image content is demanding nowadays.

Three aspects of this task, error burst correction, efficient rate allocation and random error protection are investigated in this dissertation. A novel technique, called successive packing, is proposed for combating multi-dimensional (M-D) bursts of errors. A new concept of basis interleaving array is introduced. By combining different basis arrays, effective M-D interleaving can be realized. It has …

Digital Image Processing, Russell C. Hardie, Majeed M. Hayat

Electrical and Computer Engineering Faculty Publications

In recent years, digital images and digital image processing have become part of everyday life. This growth has been primarily fueled by advances in digital computers and the advent and growth of the Internet. Furthermore, commercially available digital cameras, scanners, and other equipment for acquiring, storing, and displaying digital imagery have become very inexpensive and increasingly powerful. An excellent treatment of digital images and digital image processing can be found in Ref. [1]. A digital image is simply a two-dimensional array of finite-precision numerical values called picture elements (or pixels). Thus a digital image is a spatially discrete (or discrete-space) …

An Algorithm Using Length-R Paths To Approximate Subgraph Isomorphism, Fred Depiero, David Krout

Electrical Engineering

The ‘LeRP’ algorithm approximates subgraph isomorphism for attributed graphs based on counts of length-r paths. The algorithm provides a good approximation to the maximal isomorphic subgraph. The basic approach of the LeRP algorithm differs fundamentally from other methods. When comparing structural similarity LeRP uses a neighborhood of nodes that varies in size dynamically. This approach provides sufficient evidence of similarity to permit LeRP to form a node-to-node mapping and can be computed with polynomial effort in the worst-case. Results from over 32,000 simulated cases are reported. We demonstrate that LeRP does not need a high dynamic range of node and …

A Discrete Dimming Ballast For Linear Fluorescent Lamps, Haiyan Wang

ETD Archive

No abstract provided.

Parametrically Tunable Audio Shelving And Equalizing Ladder Wave Digital Filters, S. A. Samad

Turkish Journal of Electrical Engineering and Computer Sciences

Parametrically tunable audio equalizers are conventionally realized using allpass digital filter networks. They consist of first-order shelving filters and second-order equalizing filters. In this paper, ladder wave digital filters (WDFs) with parametrically tunable coefficients are proposed as shelving and equalizing filters. Similar to the allpass realization, the transfer function power complementary property of WDFs is used to obtain efficient shelving and equalizing filters. However, unlike the allpass structures, the transfer function and the tunable parameters of the ladder WDF are derived from the analog filter equivalent of the digital shelving and equalizing filters. For the shelving WDF, the cut-off frequency …

Speedup Of Optical Scanner Characterization Subsystem, Roger D. Clements, Elisa H. Barney Smith

Electrical and Computer Engineering Faculty Publications and Presentations

Small image deformations such as those introduced by optical scanners significantly reduce the accuracy rate of optical character recognition (OCR) software. Characterization of the scanner used in the OCR process may diminish the impact on recognition rates. Theoretical methods have been developed to characterize a scanner based on the bi-level image resulting from scanning a high contrast document. Two bottlenecks in the naïve implementation of these algorithms have been identified, and techniques were developed to improve the execution time of the software. The algorithms are described and analyzed. Since approximations are used in one of the techniques, the error of …

A New Modified Smith Predictor Design, Pauline Sourdille, Aidan O'Dwyer

Conference papers

A new modified Smith predictor structure is presented with its associated tuning rules.

A Hierarchical Approach To Computer-Aided Design Of Quantum Circuits, Marek Perkowski, Martin Lukac, Pawel Kerntopf, Mikhail Pivtoraiko, Michele Folgheraiter, Yong Woo Choi, Jung-Wook Kim, Dongsoo Lee, Woong Hwangbo, Hyungock Kim

Electrical and Computer Engineering Faculty Publications and Presentations

A new approach to synthesis of permutation class of quantum logic circuits has been proposed in this paper. This approach produces better results than the previous approaches based on classical reversible logic and can be easier tuned to any particular quantum technology such as nuclear magnetic resonance (NMR). First we synthesize a library of permutation (pseudobinary) gates using a Computer-Aided-Design approach that links evolutionary and combinatorics approaches with human experience and creativity. Next the circuit is designed using these gates and standard 1*1 and 2*2 quantum gates and finally the optimizing tautological transforms are applied to the circuit, producing a …

System Login Authentication Using Voice Recognition And Ai Methods, Benedict Sunggoh Metrius

Student Works (2000-2009)

This thesis will show how the voice recognition technique can be combined with template matching technique (Vector Quantization) to validate a login process. This system will be divided into two modules; Enrollment and Verification During the Enrollment process,the person offers a 'live sample' of his/her voice.The feature of this voice will be extracted using MFCC technique which involves Frame Blocking, Windowing, Fast Fourier Transform, Mel-frequency Wrapping and Cepstrum. The feature extracted by the MFCC will be processed and stored as codebooks. A codebook is created for each user. To confirm the identity at a future time, the individual will present …

Improving The Security And Flexibility Of One-Time Passwords By Signature Chains, Kemal Biçakci, Nazi̇fe Baykal

Turkish Journal of Electrical Engineering and Computer Sciences

While the classical attack of ``monitor the network and intercept the password'' can be avoided by advanced protocols like SSH, one-time passwords are still considered a viable alternative or a supplement for software authentication since they are the only ones that safeguard against attacks on insecure client machines. In this paper by using public-key techniques we present a method called signature chain alternative to Lamport's hash chain to improve security and flexibility of one-time passwords. Our proposition improves the security because first, like other public-key authentication protocols, the server and the user do not share a secret, thereby eliminating attacks …

An Analytical Model For Calculating Bounds On Call Blocking Probabilities In Leo Satellite Networks, A. Hali̇m Zai̇m

Turkish Journal of Electrical Engineering and Computer Sciences

We present an analytical model for calculating upper and lower bounds for call-blocking probabilities in a LEO satellite network that carries voice calls. The method is especially useful for large systems where calculation of call-blocking probabilities are too expensive. Our method calculates upper and lower bounds very easily and produces fairly accurate results.

The \Mathcal{H}_\Infty Model Matching Problem With One Degree Of Freedom Static State Feedback, Murat Akin, Ati̇lla Bi̇r

Turkish Journal of Electrical Engineering and Computer Sciences

The aim of this paper is to develop a new approach for a solution of the continuous-time model matching problem by a static state feedback in the sense of \mathcal{H}_\infty optimality criterion by using Linear Matrix Inequalities (LMIs). The main contribution could briefly be described as to reformulate the model matching problem in LMI formulation, to present the solvability conditions and to give a design procedure for the one degree of freedom static state feedback control law. Finally, the results are applied to an example system.

New Approaches For On-Line Tuning Of The Linear Sliding Surface Slope In Sliding Mode Controllers, Sezai̇ Tokat, İbrahi̇m Eksi̇n, Müjde Güzelkaya

Turkish Journal of Electrical Engineering and Computer Sciences

The main objective of this study is to propose new approaches for on-line tuning of the linear sliding surface slope in sliding mode controllers. The new approaches are developed for a class of second order systems on new coordinate axes, one of which is the classical sliding surface and the other one is naturally chosen to be orthogonal to it. The control input of the sliding mode control law is then modified accordingly by applying the Lyapunov stability condition. The adjustment of the linear sliding surface slope defined in the new coordinate axes is achieved by tuning a new parameter …

Resonant Demagnetization Pwm Forward Converter, B. Bi̇lgi̇n, Işik Çadirci, R. Ergül, M. Ermi̇ş

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a new approach to demagnetization process of a PWM forward converter (FC) is proposed. According to this approach, the demagnetization winding and diode of a conventional FC are removed, and an external capacitor is added in parallel with the secondary diode. This replacement changes the linear demagnetization process of a conventional FC into a resonant demagnetization process. The theoretical performance results of the proposed resonant demagnetization forward converter (RDFC) are compared with those of a conventional FC. A side by side comparison made between the two types of demagnetization strategies has shown that RDFC has some advantages …

A Full Adaptive Observer For Dc Servo Motors, Ata Sevi̇nç

Turkish Journal of Electrical Engineering and Computer Sciences

An adaptive observer estimating all parameters and load torque is proposed for DC servo motors. The observer uses no direct feedback but the adaptation schemes use current and speed measurements. Both the observer and adaptations are simple to implement for real-time applications. Simulation results are satisfactory for the full adaptive observer. If the observer works in parallel with only load torque and armature resistance adaptations, the results are very good even if very low-quality sensors are used. In this simulation, only a single hall sensor is used as a rotational transducer, which produces a single pulse per revolution, and very …

New Infratechnologies In The Deregulated Power Sector, Jordan Shikoski, Vladimir Katic, Risto Rechkoski

Turkish Journal of Electrical Engineering and Computer Sciences

This paper discusses new infratechnologies in the deregulated power sector. Most measurement and standardization techniques can be viewed as infratechnology. Infratechnologies are technical tools, including the measurement of data, test methods, and practices and technique. Standardization requirements are related to the measurement requirement. Although the system operation and market transactions concern many import aspects, they are insupportable and often complementary. This distinction between the technical and market information is important because the characteristics of information needs and the impact on economic efficiency and clean power are generally different. The present paper focuses on infratechnologies that can potentially increase the benefits …

A Digitally Controlled Drive System For Travelling-Wave Ultrasonic Motor, Güngör Bal

Turkish Journal of Electrical Engineering and Computer Sciences

A digitally controlled drive system was implemented in this study to control the speed and direction of a travelling-wave ultrasonic motor. The drive system, based on a 2-phase voltage-fed high-frequency serial-resonant inverter, uses the mechanical resonant frequency of an ultrasonic motor. A TMS320F243 digital signal processor was used to control an ultrasonic motor drive system. The speed control of the ultrasonic motor was achieved with a driving frequency in the 41.3-43.3 kHz frequency range. The feasible evaluations of the proposed drive and control system were tested by experiments. Experimental results demonstrated that the proposed drive and control system is flexible …

Initiatory Electrons In Compressed Gases In Positive Polarity, Mohammed Messaad, Mustapha Tioursi

Turkish Journal of Electrical Engineering and Computer Sciences

This paper deals with the nature of seed electron sources in compressed N_2 for positive polarity. We present an experimental procedure that provides evidence of the fact that collisional detachment from negative ions plays the most important role in the supply of seed electrons. Conditioning phenomena in compressed SF_6, N_2 and air have been simulated under positive lightning impulses for point-plane geometry.

A New Simulator For Hvdc/Ac Systems-Part I, Baktiar Zangeneh, Abbas Shoulaie

Turkish Journal of Electrical Engineering and Computer Sciences

A simulator with optimal step time (SOST) has been designed to investigate Large HVdc/ac systems. The adequacy and robustness of the simulator will be demonstrated by showing some important applications relevant to operation, operational planning and medium-term planing. Some of the features of our SOST simulator are optimal step time algorithm, interpolation, chatter removal, MATLAB interface, unlimited size of ac system, and Farsi command that help model complex power electronic circuits, provide fast and accurate results. On account of its reduced calculation effort and deterministic execution time, optimal-step simulation is a prerequisite for real-time performance. However, when simulating electromagnetic-transients behavior, …

A New Simulator For Hvdc/Ac Systems-Part Ii, Baktiar Zangeneh, Abbas Shoulaie

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a performance comparison (the focus of numerical simulation) of traditional simulation (TCS,TSE) with an optimal step time simulator (SOST) for large HVdc systems.In SOST, a Detailed simulation of HVdc converter behavior has been modified to include the automatic selection of optimal integration steps, frequency-dependent effects of an ac system, ac system phase and magnitude dynamics of voltage (particularly weak ac systems), control assessment and temporary over-voltage consequences. SOST, via graphical interfaces,provides fast and accurate information of electromechanical and the electromagnetic-transients behavior of a large HVdc/HVac system.

Source Motion Mitigation For Adaptive Matched Field Processing, Lisa M. Zurk, Nigel Lee, James Ward

Electrical and Computer Engineering Faculty Publications and Presentations

Application of adaptive matched field processing to the problem of detecting quiet targets in shallow water is complicated by source motion, both the motion of the target and the motion of discrete interferers. Target motion causes spreading of the target peak, thereby reducing output signal power. Interferer motion increases the dimensionality of the interference subspace, reducing adaptive interference suppression. This paper presents three techniques that mitigate source motion problems in adaptive matched field processing. The first involves rank reduction, which enables adaptive weight computation over short observation intervals where motion effects are less pronounced. The other two techniques specifically compensate …

Common- And Differential-Mode Signaling And Filtering, Zhe Li

Masters Theses

"Common-mode chokes are widely used as suppression filters against interference of common-mode noise in high-speed differential signaling. This thesis focuses on investigating the characteristics of common-mode chokes. Mixed-mode S-parameters are presented as a useful concept for explaining the modal operation of differential circuits.

Three methods for measuring common-mode and differentia-mode S-parameters of common-mode chokes are demonstrated. The three methods involve (1) ABCD chain matrix, 2) using hybrid couplers and 3) modal decomposition. Each measurement method provides a specific level of accuracy. The modal decomposition method can work up to 10GHz.

SPICE equivalent circuit model of common-mode chokes and the extraction …