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The following topics are dealt with: power and energy; optics, optoelectronics, nanotechnology and materials; communications and networking; embedded systems; control, automation, military and security applications; electromagnetics and microwaves; robotics and computer vision; computer and software engineering; engineering education; instrumentation; and signal/image processing, bioengineering and...
This paper presents the results of a study on determining Zone-1 reach settings for transmission line distance relays to prevent overreach resulting from coupling capacitor voltage transformer (CCVT) transients. In particular, this study focused on digital distance relays and determining appropriate relay reach settings to account for the effects of CCVT transients during faults for CCVTs with active...
The Coupled Leakage Model of a multiple winding transformer is an extension of a commonly used transformer model, but accounts for the coupling between multiple secondaries. Leakage inductance is included in each of the multiple secondary windings, however this model introduces an effective coupling coefficient between the leakages. The model is explored further, is shown to be easily adapted to circuit...
This paper presents modeling methods for overhead transmission lines with segmented shield wires, as well as signal attenuation calculation for different coupling methods for use in power line carrier (PLC) systems. The purpose of this paper is to present a generalized method to model transmission lines with segmented shield wires, along with steps for signal attenuation calculation in the phase domain...
At this time, the restructuring of power system is going to pass the early stages and become a well-known concept. However, it is impossible to say that supplying electricity is perfect now. There are still many works undergoing to increase the efficiency and functionality of restructured electricity markets. In this paper, a new concept for electricity markets has been proposed. This new concept...
Although there is considerable progress in the wind energy conversion technology, most of the currently installed wind turbines are using induction generators to convert mechanical energy to electrical one. The induction generators which are utilized in wind turbines and wind farms consume high amount of reactive power. Beside, since there is no voltage regulation installed for induction machines...
The performance of an optical imaging system is fundamentally limited by the wave nature of light. More specifically the lateral resolution of an image has traditionally been dictated by Abbe's limit, to be approximately one-half of the wavelength. The pursuit of exceeding this limit is a growing interest in several research areas. The goal of these pursuits will be to achieve super-resolution imaging,...
We present experimental results of direct extraction of chirp parameter made possible by temporal phase retrieval measurements of ultrafast pulses. Results for a multi-spatial-mode mode-locked semiconductor laser at various bias points are presented. The comparison with the normally used root-mean-square (r.m.s.) chirp parameter reveals that the correlation of the r.m.s. chirp parameter with the actual...
We have investigated conduction in a closely packed nanocluster array of copper with a copper oxide nano shell as a function of temperature. The result is found to be nonlinear and shows a sudden increase in electrical conductivity above a critical temperature. An attempt has been made to explain this anomalous behavior in terms of electrical and physical properties of the metallic nanostructure.
This paper reports a reversible microfludic biosensor based on liquid crystal (LC) orientation transition. The biosensor was fabricated using poly(dimethylsiloxance) (PDMS) and glass. Dilauroylphosphatidylcholine (DLPC) was used to trigger the orientational transition that was easily observed optically.
Cognitive radio has been put forward to make efficient use of scarce radio frequency spectrum. Spectrum sensing is the cornerstone of cognitive radio. As a part of the effort toward building a cognitive radio network testbed, we have demonstrated real-time spectrum sensing. However, current hardware platforms for cognitive radio introduce time delays that actually undermine the accuracy of spectrum...
Response delay problem and measurements of such delays have been reported in Part I. The response delay has a negative impact on the accuracy of spectrum sensing, which is the cornerstone of cognitive radio. In this paper, single-user prediction of channel state is proposed to minimize the negative impact of response delays caused by hardware platforms. Specifically, a modified hidden Markov model...
Piecewise polynomials have been used to visually link and classify network traffic. The advantage of using piecewise polynomials to approximate traffic is that significantly less storage space is required when compared to traditional packet captures. However, when representing discrete data with continuous approximations, error is introduced. We analyze this error through the creation and examination...
This paper reports a research testbed of real-time ultra-wideband (UWB) multiple-input multiple-output (MIMO) radio. In the receiver design, the UWB MIMO receiver supports up to eight channels, where each channel is equipped with an analog-to-digital converter (ADC) with 8-bit resolution and sampling rate up to 3 Giga samples per second (Gsps). The transmitter is able to transmit two independent arbitrary...
A photovoltaic (PV) array performance depends on various operating conditions. Solar irradiation is considered the most important factor. The shading on PV array can result from passing clouds, trees, utility, telephone poles, or neighboring buildings. It causes not only power losses, but also increases non-linearity of V-I characteristics of PV array. This phenomenon has been studied in many research...
The intelligent, robust and fast multi-class classification of power system disturbances is very important to improve control algorithms for ensuring power system security and reliability, an essential function for smart grid infrastructure. Moreover, in a future power system mostly consisting of distributed generators and renewable energy resources on which the disturbance has more impact, the analysis...
Under-Frequency Load Shedding (UFLS) can increase power system reliability by preventing total system collapse during emergency operating situations when load exceeds generation. UFLS is required by The North American Electric Reliability Council (NERC) for large consumers and has been implemented by utilities across the country. When the frequency drops to some predefined set points, feeder breakers...
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