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An artificial immune system (AIS)-based control of generator excitation systems for the U.S. Navy's electric ship is presented in this paper to solve power quality problems caused by high-energy loads such as direct energy weapons. The coordinated development of the AIS controllers mainly consists of two parts—innate immunity (optimal) and adaptive immunity. The parameters of the controllers for the former, to provide optimal performance, are determined simultaneously using particle swarm optimization. For dramatic changes in the ship's power system, adaptive control based on the immune system feedback law is developed. The feedback law adapts the controllers' parameters only during transient disturbances. After the disturbance, the controllers' parameters are restored to their innate values. A ship's real-time power system and the proposed AIS control of all excitation systems have been implemented on a real-time digital simulator and a digital signal processor, respectively. Results from the hardware-in-the-loop studies show that the AIS controllers can provide effective control of all generators' terminal voltages during pulsed loads, restoring and stabilizing them quickly. [ABSTRACT FROM PUBLISHER]

Examines the implementation of the trellis en/decoder in the grand alliance digital television system by the Advanced Television (TV) System Committee in the United States. Popularity of digital TV; Replacement of current TV broadcasting system by advanced TV system; Introduction of decoding algorithm for convolutional codes.

Residential energy consumption accounts for 21% of the total electricity use in the United States. Unfortunately, research indicates that almost 41% of this power is wasted. Changing the way that consumers use energy may be important in reducing home energy consumption. This paper looks at whether the implementation of certain real-time energy monitors has an impact on the residential rate of energy consumption in a metropolitan area with relatively low electricity rates. In the following case study, 151 Omaha residences were equipped with two variants of the Aztech In-Home Display (Aztech) as well as the Blue Line Power Cost Monitor (PCM) real-time energy monitors for a period of 16 months. The results of the data, 30 days after installation, revealed a statistically insignificant reduction of 12% in mean electrical consumption in houses equipped with a PCM and no reduction in mean consumption in homes using either variants of the Aztech device when compared to a randomly selected control sample. However, they proved effective in the short term if utilized by utilities for mass distribution to foster awareness among participating residents of their own patterns of residential electricity consumption and on the environmental impacts of energy saving. [ABSTRACT FROM AUTHOR]

This paper deals with the power generation control in variable-speed wind turbines. These systems have two operation regions which depend on wind turbine tip speed ratio. A high-order sliding-mode control strategy is then proposed to ensure stability in both operation regions and to impose the ideal feedback control solution in spite of model uncertainties. This control strategy presents attractive features such as robustness to parametric uncertainties of the turbine. The proposed sliding-mode control approach has been validated on a 1.5-MW three-blade wind turbine using the National Renewable Energy Laboratory wind turbine simulator FAST (Fatigue, Aerodynamics, Structures, and Turbulence) code. Validation results show that the proposed control strategy is effective in terms of power regulation. Moreover, the sliding-mode approach is arranged so as to produce no chattering in the generated torque that could lead to increased mechanical stress because of strong torque variations. [ABSTRACT FROM AUTHOR]

Under a nonideal situation, the image quality may vary. As a result, the traditional iris recognition systems would not work well. However, these kinds of iris recognition systems have been widely deployed in law enforcement and homeland security. It will be desirable to transform the traditional systems to perform in nonideal situations without a costly update. In this paper, we propose a method that upgrades the traditional iris recognition system to work on nonideal situations. The proposed method takes into consideration not only the effect of image quality but also the segmentation accuracy. It employs video-based image-processing techniques to quickly identify and eliminate the bad quality images from iris videos for further processing. The proposed method is tested on public databases using in-house recognition algorithms and also evaluated using a commercialized system. The research results show that the proposed methods can be used to improve the performance of iris recognition systems in a nonideal situation. [ABSTRACT FROM AUTHOR]

Fuzzy controllers are used in many applications because of their rapid design by translating heuristic knowledge, robustness against perturbations, and smoothness in the control action. However, they require parallel processing and special operators (such as fuzzification or defuzzification) which are not available in standard digital signal processors (DSPs), thus complicating their direct implementation. This paper describes an efficient design methodology that allows starting with any kind of fuzzy controller and subsequently transforming it until a system suitable for easy DSP implementation is obtained. Such methodology is greatly aided by the design environment Xfuzzy 3. The parking problem of an autonomous robot is described to illustrate the steps of this methodology. Real experiments with the autonomous robot ROMEO 4R demonstrate efficiency of the designed fuzzy controller embedded into a stand-alone card based on a fixed-point DSP from Texas Instruments. [ABSTRACT FROM AUTHOR]

Presents an integrated regenerative frequency converter motor prototype for industry applications in the U.S. Features of the converter motor prototype; Disadvantages of matrix converter; Efficacy of the prototype.

Focuses on data acquisition and feedback control of electron-beam positions in the Duke University Free-Electron Laser Facility in North Carolina. Composition of the control system; Provision of graphical data presentation to the user; Control of electron-beam profile by electromagnetic forces.

Presents the table of contents for this issue of the periodical. [ABSTRACT FROM PUBLISHER]

Describes a type of optical fiber wavelength-division-multiplexed (WDM) analog transmission system for use in factory communications in the U.S. Transmission through plastic optical fibers; Performance of transmission system; Composition of WDM system.

Identifies solutions for industrial matrix-converter applications in the U.S. Implementation of rectifying and inverting vector modulation; Application of insulated gate bipolar transistors; Protection of overvoltage.