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The specific aim of this paper is to model the vision-posture coupling behavior, which is important for astronauts to stabilize their locomotion in partial gravities as the National Aeronautics and Space Administration plans for manned missions to the Moon and Mars [1]. As such, an optimal scheme is assumed in postural-control processes to stabilize visual optical flows. An experiment was conducted, in which human subjects attended a visual-gait tracking task. In tracking control, head position errors can be used to regulate inputs so that appropriate compensatory changes can be obtained. The "optimal" scheme describes a compromise between postural adjusting efforts and tracking errors. The results show that the proposed optimal-control model describes the gait tracking process more reliably than McRuer's crossover model of the human-plant compensatory behaviors. In practice, if the tracking goal is to be roughly right rather than precisely wrong, this paper also provides the experimental data regarding the human tolerance and achievable performance under various unloading conditions and tracking difficulties. This information and related experimental setup could also be applied to postsurgery gait rehabilitation. [ABSTRACT FROM AUTHOR]

The Universities of Texas, Minnesota, and New Orleans, and Texas Tech University are undertaking research supported by the Air Force Office of Scientific Research on critical issues for a launch to space from a railgun carried on an airborne platform. The University of Texas at Austin is studying techniques to achieve hypervelocity with a goal of 7 km/s: So far, 5.2 km/s has been achieved in a 7-m augmented railgun using a preinjected plasma armature. Texas Tech University is studying distributed power feed concepts that will improve the efficiency of launch for a long railgun: So far, 11 km/s has been achieved with a plasma arc in a five-stage system. The Universities of Minnesota and New Orleans are investigating the aerothermal behavior of a 10-kg projectile for flight from a high-altitude launch into orbit: So far, the results show that an acceptable amount (∼15 mm) of nosetip ablation will occur. This paper provides an overview of progress in these areas; more details on specific topics are provided in companion papers. [ABSTRACT FROM AUTHOR]

A very popular method utilized in quantifying the benefit of power delivery service reliability is to estimate the customer monetary losses associated with power supply interruptions by collecting data with customer surveys. MidAmerican Energy Company, a Midwest utility, recently performed surveys of its customers in the residential, commercial, industrial, and company/organization sectors. This paper presents the industrial and commercial customer results of these surveys with primary focus on the cost results. The results of this paper are compared with the results of other studies performed in high-cost areas of the United States' east and west coasts. This is the first ever paper of this nature performed for the electrical customers in the United States' Midwest region. Methodological differences in study design compared with coastal surveys are discussed. The major contribution of this paper is that particulars of Midwest customers compared with customers of coastal utilities are noted, the impact on customers with backup supply is identified, a suggested approach to enhance customer satisfaction due to advance warning on outages is recommended, and relatively high survey response return rates are elaborated. The customer damage functions derived from the survey results are being routinely used in power delivery project justifications in annual delivery system budgeting processes. [ABSTRACT FROM AUTHOR]

This paper updates an earlier report by the authors that studied electrical injuries from 1992 to 1998. The previous information is expanded and supplemented with fatal and nonfatal injury rates and trends through 2002. Injury numbers and rates were used to compare and trend electrical injury experience for various groups and categories. This information allowed identification of at-risk groups that could most benefit from effective electrical safety interventions. The data presented in this paper are derived from the U.S. Labor Department's Bureau of Labor Statistics' Census of Fatal Occupational Injuries, Survey of Occupational Illnesses and Injuries, and Current Population Survey. Between 1992 and 2002, 3378 workers died from on-the-job electrical injuries. Electricity remained the sixth leading cause of injury-related occupational death. From 1999 to 2002, 4.7% of all occupational deaths were caused by electricity, down from 5.2% in the 1992-1998 time period. The cause of death was listed as electrocution in 99.1% of fatal cases. Contact with overhead power lines was involved in 42% of all on-the-job electrical deaths. The construction industry accounted for 47% of all electrical deaths between 1992 and 2002 but showed overall improvement from 1995 to 2002 by reducing its electrical fatality rate from 2.2 to 1.5 per 100 000 workers. In addition, 46 598 workers were nonfatally injured by electricity. Contact with electric current of machine, tool, appliance, or light fixture and contact with wiring, transformers, or other electrical components accounted for 36% and 34% of nonfatal electrical injuries, respectively. Contact with underground buried power lines was involved with 1% of fatal injuries and 2% of nonfatal injuries. The research of the National Institute for Occupational Safety and Health aimed at evaluating commercially available overhead power line proximity warning alarms is described. This paper is expected to be the initial step for eventual development of a performance standard for such systems. [ABSTRACT FROM AUTHOR]

This paper describes results from a channel measurement campaign performed at several small airports in the U.S. in the 5-GHz band. This paper is a companion to another paper, which describes channel models for large airports. We classify the small airport surface channel into three propagation regions based upon different delay dispersion conditions. The channel characteristics of these regions in the delay and frequency domains are discussed with examples. We provide empirical stochastic channel models (of different bandwidths) to accurately represent the channel on the airport surface area for all propagation regions. The models are provided in the form of tapped delay lines, and complete statistical tap descriptions are given. Several key observations, including the presence of severe amplitude fading, some correlated scattering, and statistically nonstationary behavior, are also discussed. [ABSTRACT FROM AUTHOR]

This paper discusses power-system instability and the importance of fast fault-clearing performance to aid in reliable production of power. An explanation regarding small-signal stability, high-impedance transmission lines, line loading, and high-gain fast-acting excitation systems is provided. Transient stability is discussed, including synchronizing and damping torques. The power-angle curve is used to illustrate how fault-clearing time and high initial response excitation systems can affect transient stability. The term "power-system stability" has become increasingly popular in generation and transmission. The sudden requirement for power-system stabilizers (PSSs) has created confusion about their applicability, purpose, and benefit to the system. This paper discusses the fundamentals of the PSS and its effectiveness. In today's paper industry, PSSs are being applied on larger machines in the northwest United States and Canada. [ABSTRACT FROM AUTHOR]

Increasingly, stakeholders are asking or requiring organizations to be more environmentally responsible with respect to their products and processes; reasons include regulatory requirements, product stewardship, public image, and potential competitive advantages. This paper presents an exploratory study of the relationships between specific environmentally sustainable manufacturing practices, and specific competitive outcomes in an environmentally important but under-researched industry, the U.S. commercial carpet industry. In general, empirical research on the impact of environmental practices on organizational outcomes is inconclusive, partly due to limitations of earlier studies. This paper addresses some of these limitations, and surveys the entire U.S. commercial carpet industry; respondents represent 84% of the market. Findings suggest that environmentally sustainable manufacturing practices may be positively associated with competitive outcomes. In particular, different types of environmentally sustainable manufacturing practices (e.g., pollution prevention, product stewardship) are associated with different competitive outcomes (e.g., manufacturing cost, product quality). These specific findings can be helpful to engineering and operations managers as they respond to environmental and competitive demands. [ABSTRACT FROM AUTHOR]

In 1966, following a decade of discovery and development on A15 compounds, Richard Garwin and Juri Matisoo [1], two research staff members then in the IBM Research Division, submitted for publication a paper examining the prospect to employ one of the most promising of these materials, Nb3Sn, in a cable system for transmission of electricity. The scale of their proposal was truly enormous -100 GW (+/-100 kV at 500 kA direct current) over a distance of 1000 km, the entire length refrigerated by liquid helium. At the time, such a cable would have been capable of carrying half the entire electric power generated in the United States, and about one-tenth today. This paper will revisit their vision in the context of the subsequent discovery of high temperature superconductivity twenty years later, and the now emerging availability of long lengths of high performance wire and tape for operation in the 20–80 K range. Whereas the scenario set by Garwin and Matisoo addressed the one-way transmission of electricity from remote coal and nuclear generation multi-plant ‘farms’ to large population centers, we will extend their picture to include two-way transmission on a diurnal or longer period to take advantage of regional electricity pricing and production which has resulted from the deregulation of generation. We conclude that the advent of high temperature superconductivity substantially extends and brings closer both the technical and economic feasibility of Garwin and Matisoo's dream. However, we note, as did they, the caveat that ‘whether it is desirable or necessary is another matter entirely.’ We believe this question will be decided in the affirmative as societal demands continue to increase for the clean, reliable and ecologically gentle delivery of large amounts of electric power, a need that was foreseen but not as overriding forty years ago as it is now. [ABSTRACT FROM AUTHOR]

This paper is the second of a two-part paper and describes the application of a multiperiod generalized network flow model that is used to analyze the economic efficiencies of the energy movements from the coal and natural gas suppliers to the electric load centers, providing a simulation tool that captures dynamics of and interdependencies between the coal, natural gas, and electricity networks. The modeling approach, mathematical formulation, and modeling assumptions are presented in part I. This sequel presents and discusses numerical results to illustrate the application of the model. The model enables public and private decision makers to carry out comprehensive analyses of a wide range of issues related to the energy sector, such as strategic planning, economic impact assessment, and different regulatory regimes. [ABSTRACT FROM AUTHOR]

This paper is the first of a two-part paper presenting a multiperiod generalized network flow model of the integrated energy system in the United States. Part I describes the modeling approach used to evaluate the economic efficiencies of the systemwide energy flows, from the coal and natural gas suppliers to the electric load centers. Under the proposed problem formulation, fuel supply and electricity demand nodes are connected via a transportation network, and the model is solved for the most efficient allocation of quantities and corresponding prices. The methodology includes physical, economic, and environmental aspects that characterize the different networks. Part II of this paper provides numerical results that demonstrate the application of the model. [ABSTRACT FROM AUTHOR]

Condition monitoring of electric motors avoids severe economical losses resulting from unexpected motor failures and greatly improves the system reliability and maintainability. Efficiency estimation, which shares many common requirements with condition monitoring in terms of data collections, is expected to be implemented in an integrated product. This brings more considerations into the selection of the efficiency-estimation methods. This paper presents the results of an up-to-date literature survey on efficiency-estimation methods of in-service motors, particularly with considerations of the motor-condition-monitoring requirements. More than 20 of the most commonly used methods are briefly described and classified into nine categories according to their physical properties. Six categories of these methods are more related to in-service testing and are compared in a table summarizing the required tests and measurements, intrusion level, and average accuracy. Estimation of the rotor speed and the stator resistance, the two stumbling blocks of various efficiency-estimation methods, is also carefully studied; commonly used methods are summarized. Based on the survey results, four efficiency-estimation methods are suggested as candidates for nonintrusive in-service motor-efficiency estimation and condition-monitoring applications. Another contribution of this paper is that a general approach for developing nonintrusive motor-efficiency-estimation methods is proposed, incorporating rotor speed, stator resistance, and no-load loss estimations. [ABSTRACT FROM AUTHOR]

This paper describes several small printed circuit board planar antennas that can be integrated with amplifiers for short-range vehicle wireless communication. The antennas are designed for the 315-MHz frequency band, which is commonly used for control and security devices in the USA and Canada. Each antenna has dimensions of 50 × 70 mm (much less than the free-space wavelength λ = 0.95 m) and is implemented on FR-4 dielectric substrate. These investigated antennas were compared with respect to input impedance, radiation resistance, radiation efficiency, directivity, directionality, bandwidth, matching system complexity, and gain. This paper also includes experimental verification of the final antenna design in the vehicle. It is shown that the antenna diversity method can increase communication range for remote keyless entry systems. [ABSTRACT FROM AUTHOR]

Current spatial database systems offer limited querying capabilities beyond binary topological relations. This paper introduces a model for projective relations between regions to support other qualitative spatial queries. The relations are ternary because they are based on the collinearity invariant of three points under projective geometry. The model is built on a partition of the plane into separate zones that are obtained from projective properties of two reference objects: Then, by considering the empty/nonempty intersections of a primary object with these zones, the model is able to distinguish between 34 different projective relations. Then, the paper proposes original algorithms for computing the relations under the assumption that regions of the plane are stored as vector polygons in a spatial database. These algorithms run in optimal O(n log n) time. [ABSTRACT FROM AUTHOR]

An advanced high side voltage control (HSVC) that can improve power system stability by adding supplemental con- trol to conventional generator excitation systems has been developed. Since the introduction of this advanced HSVC at the IEEE PES 2000 Summer Meeting, additional development has further improved the advanced HSVC as reported in a companion paper. This paper describes field verification results for the HSVC that were carried out on a hydro power plant of the U.S. Army Corps of Engineers on the Columbia River at The Dalles. The advanced HSVC was temporarily added to the existing digital automatic voltage regulators (AVRs) of two generators in a 22-machine hydro power plant. Various tests, such as confirmation of droop, performance of the cross-current suppression function, switching on and off of a nearby capacitor bank, and others, were successfully carried out. It was confirmed through these field verification tests that the advanced HSVC displayed beneficial impacts on voltage control and system stability as compared to a conventional AVR. [ABSTRACT FROM AUTHOR]

In a mobile telecommunications network, the period when a mobile station (MS) resides in a cell (the radio coverage of a base station) is called the cell residence time of that MS. The period between when a call arrives at the MS and when the MS moves out the cell is called the excess life of the cell residence time for that MS. In performance evaluation of a mobile telecommunications network, it is important to derive the excess life distribution from the cell residence times. This distribution determines if a connected call will be handed over to a new cell, and therefore significantly affects the call dropping probability of the network. In mobile-telecommunications-network simulation, generating the excess-life random numbers is not a trivial task, which has not been addressed in the literature. This paper shows how to generate the random numbers from the excess life distribution, and develop the excess-life random number generation procedures for cell residence times with gamma, Pareto, lognormal, and Weibull distributions. This paper indicates that the generated random numbers closely match the true excess-life distributions. [ABSTRACT FROM AUTHOR]

In this paper, the authors study the performance of scheduling algorithms exploiting the multiuser selection diversity. Schedulers with affordable-rate transmission and adaptive transmission based on the absolute signal-to-noise ratio (SNR) and the normalized SNR are considered. In contrast to previous studies on the multiuser-diversity systems, the channel dynamics is taken into consideration in this paper by a novel formulation based on the level crossing analysis of stochastic processes. Then, the authors make the connection between the Doppler frequency shift, which indicates the channel temporal correlation, and the average (channel) access time, the average waiting time (AWT) between accesses, and the average access rate (AAR) of active users. These properties are important for the scheduler design, especially for applications where delay is a concern. In addition, analytical expressions for the system throughput and the degree of fairness (DOF) when users have nonidentical average channel conditions are presented. These expressions quantify the effect of disparateness in users' average channel conditions on the system performance. [ABSTRACT FROM AUTHOR]

Reverse link capacity of a direct-sequence code-division multiple-access (DS-CDMA) system in a multicell environment has been studied recently, and significant capacity improvements due to the use of beamforming have been observed. However, system performance with beamforming will be affected by several impairments, such as direction of arrival estimation errors, array perturbations, mutual coupling, and signal spatial spreads. In this paper, reverse link performance of CDMA systems with beamforming under these impairments (imperfect beamforming) is investigated. A simplified beamforming model is developed to evaluate the system performance in terms of user capacity, bit-error rates (BER), and outage probabilities. Both signal-to-interference-ratio-based power control and strength-based power control are considered in this paper. The capacity and BER degradations due to different impairments are shown, and outage probabilities under different power control schemes are examined. [ABSTRACT FROM AUTHOR]

This paper considers a realistic evaluation of the power mobile handsets are able to transmit and receive. It has been suggested to use the so-called total radiated power (TRP) and the total isotropic sensitivity (TIS) for the uplink and downlink, respectively, which may be seen as special cases of the general mean-effective-gain (MEG) measure. These measures are computed from the spherical radiation pattern of the handset and the different measures are obtained by using different models of the mobile propagation environment. In this paper, the results obtained via the spherical radiation patterns are compared with the equivalent performance obtained in a live Global System for Mobile Communications (GSM) network using data from the Abis network interface. This method does not require altering of the handsets and the testing uses normal calls in the network. The investigation is based on measurements with four different commercially available handsets carried out in two different indoor environments and involving 22 test users. In addition, a series of measurements were also made with a phantom simulating the handset user, allowing a test of how well the phantom represents the average user. [ABSTRACT FROM AUTHOR]

There has been recent extensive research on integrating cellular networks and ad hoc networks to overcome the limitations of cellular networks. Although several schemes have been proposed to use such hybrid networks to improve the performance of individual multicast groups, they do not address quality of service (QoS) issues when multiple groups are present. This paper, on the other hand, considers an interesting scenario of hybrid networks when an ad hoc network cannot accommodate all the groups and a base station has to select a subset of groups to optimize its bandwidth savings and maximize the utilization of the ad hoc network while providing QoS support for multicast users. In this paper, a network model for multicast admission control that takes wireless interference into account is developed, the group selection problem is formulated as a multidimensional knapsack problem, and an integer linear programming (ILP) formulation and a polynomial-time dynamic algorithm are proposed. A distributed implementation of the dynamic algorithm in real systems is also examined. Simulation studies demonstrate that the dynamic algorithm is able to achieve very competitive performance under various conditions, in comparison with the optimal solution computed by the ILP approach. [ABSTRACT FROM AUTHOR]

A complete complementary code based direct sequence code division multiple access (CC/DS-CDMA) system has been proposed recently as a potential candidate for beyond third generation (B3G) wireless communications. This paper addresses the issues that design of efficient code assignment schemes should be based on a flexible physical layer support, which is extremely important for emerging cross-layer designs in future wireless applications. The study in this paper considers a CC/DS-CDMA system with multiple time slots, three traffic classes and two dynamic code-flock assignment schemes, namely random assignment (RA) and compact assignment (CA). Simulation results show that the CC/DS-CDMA system has variable capacity property (VCP), which is sensitively affected by different code-flock assignment schemes. In general, CA can offer lower blocking probability, whereas RA can offer a larger mean system capacity and higher throughput when offered traffic is heavy. [ABSTRACT FROM AUTHOR]

The article discusses about the special section on cross-layer design for mobile ad hoc networks and wireless sensor networks published within the May 01, 2006 issue in the U.S. The first section, which consist of seven papers, focuses on the capacity analysis/enhancement and quality-of-service support. The following papers, from eight to twelve, address the routing issues. In addition, four paper after the 12th explores the idea of cross-layer design.

The Ozone Monitoring Instrument (OMI) was launched on July 15, 2004 on the National Aeronautics and Space Administration's Earth Observing System Aura satellite. OMI is an ultraviolet-visible imaging spectrograph providing daily global coverage with high spatial resolution. This paper discusses the ground data processing software used for Level 0 to Level lb processing of OMI data. In addition, the OMI operations scenario is described together with the data processing concept. This paper is intended to serve as a reference guide for users of OMI (Level 1b) data. [ABSTRACT FROM AUTHOR]

Online advertising continues to be a significant source of income for many Internet-based organizations. Recent indications of improved economic growth are having an impact on advertisement revenue, with the estimated online advertising revenue in the United States for the fourth quarter of 2003 totaling a record of $2.2 billion. A substantial portion of this income comes from banner advertisements, and efficient scheduling of these advertisements could result in a considerable increase in profits. The problem of scheduling banner advertisements has been observed to be intractable via traditional optimization techniques and has received only limited attention in the literature. In addition, all past attempts to address this problem have been based on an ‘all-or-nothing’ framework, where a customer specifies the exact number of copies of the ad to be displayed over the planning horizon, if it is selected for display by the provider of the advertisement space. This paper extends it to a more realistic setting, where the customer is allowed to specify a set of acceptable display frequencies. The Lagrangian decomposition-based solution approaches presented in this paper are observed to provide good schedules in a reasonable period of time. [ABSTRACT FROM AUTHOR]

The Multispectral Thermal Imager (MTI) satellite is a research and development project sponsored by the U.S. Department of Energy. The primary mission is to demonstrate advanced multispectral and thermal imaging from a satellite, Including new technologies, data processing, and analysis techniques and validation by reference to ground truth. The MTI builds on the efforts of a number of earlier efforts, Including Landsat, National Aeronautics and Space Administration remote sensing missions, and others, but the MTI incorporates a unique combination of attributes designed to advance the state of the art. The MTI satellite was launched on March 12,2000 into a 580 km × 610 km, sun-syn-chronous orbit with nominal 1 A.M. and 1 P.M. equatorial crossing times. The Air Force Space Test Program provided the Orbital Sciences Taurus launch. The satellite-based sensors obtain radiance data that are subsequently processed into measurements of atmospheric and surface properties such as column water vapor, atmospheric aerosol loading, surface temperatures, material composition, and others. This paper provides an overview of the MTI research objectives, design, operations, data products, and data processing and analysis. Several other papers provide greater detail on selected topics. [ABSTRACT FROM AUTHOR]

This paper investigates factors affecting the, post-adoption behavior of first-Her supply chain members within the U.S. automotive industry toward a new information technology. This paper examined a specialized information technology known as the collaborative visibility network (CVN) used within the U.S. automotive industry that provides enhanced part-level visibility to Its supply chain affiliates. Using existing research on innovation diffusion, this paper examines cognitive and experiential antecedents of post-adoption behavior. A model grounded in innovation diffusion theory, social learning theory, and the technology acceptance model is proposed and tested. Field interviews followed by a mail survey were used to collect data from 515 first-tier supply chain users of CVN. A structural equation model tested the hypothesized relationships to support the proposed model. Results confirmed the majority of the hypotheses. The opportunity to experiment, training effectiveness, prior experience with a similar technology, and prior technological knowledge have an effect on perceived ease of use and perceived usefulness, which ultimately affect technology performance. Implications of this study along with suggestions for future research are provided. [ABSTRACT FROM AUTHOR]

This paper presents experimental results obtained at the International Center for Lightning Research and Testing (ICLRT) at Camp Blanding, Florida during the summers of 2002 and 2003. Currents induced by triggered and natural lightning events were measured at the terminations of a buried power cable, in the cable shield, and in the inner cable conductor. Measurements of the horizontal component of the magnetic field above the ground surface for both natural and triggered lightning are also presented. For distant natural lightning events, locations of ground strike points were determined using the U.S. National Lightning Detection Network (NLDN). Based on the theoretical developments presented in Part I of this paper [14], the field-to-buried cable coupling equations are solved in both the time domain and in the frequency domain. The obtained experimental results are then used to validate the numerical simulations provided by the relevant developed codes. [ABSTRACT FROM AUTHOR]

The USA and Europe use different standards to provide electrical safety for employee workplaces. This paper examines the two standards NFPA70E and EN 50110, shows some of the similarities and differences, and looks at the possibilities for a gradual harmonization between the two systems. The paper would contribute to improve the electrical safety continuity in the worldwide globalization efforts. [ABSTRACT FROM AUTHOR]

We describe a hierarchical Bayesian model for assessing the early reliability of complex systems, for which sparse or no system level failure data are available, except that which exists for comparable systems developed by different categories of manufacurers. Novel features of the model are the inclusion of a "quality" index to allow separate treatment for systems produced by "experienced" & "inexperienced" manufacturers. We show how this index can be employed to distinguish the behavior of systems. produced by each category of manufacturer for the first few applications, with later pooling of outcomes from both categories of manufacturers after the first few uses (i.e., after inexperienced manufacturers gain experience). We demonstrate how this model, together with suitable informative priors, can reproduce the reliability growth in the modeled systems. Estimation of failure probabilities (and associated uncertainties) for early launches of new space vehicles is used to illustrate the methodology. Disclaimer--This paper is provided solely to illustrate how hierarchical Bayesian methods can be applied to estimate systems reliability (including uncertainties) for newly introduced complex systems with sparse or nonexistent system level test data. The example problem considered (i.e. estimating failure probabilities of new launch vehicles) is employed solely for illustrative purposes. The authors have made numerous assumptions & approximations throughout the document in order to demonstrate the central techniques. The specific methodologies, results, and conclusions presented in this paper are neither approved nor endorsed by the United States Air Force or the Federal Aviation Administration. [ABSTRACT FROM AUTHOR]

Audio watermarking is usually used as a multimedia copyright protection tool or as a system that embed metadata in audio signals. In this paper, watermarking is viewed as a preprocessing step for further audio processing systems: the watermark signal conveys no information, rather it is used to modify the statistical characteristics of an audio signal, in particular its nonstationarity. The embedded watermark is then added in order to stationnarize the host signal. Indeed, the embedded watermark is piecewise stationary, thus it modifies the stationarity of the original audio signal. In some audio processing fields, this fact can be used to improve performances that are very sensitive to time-variant signal statistics. This paper presents an analysis of the perceptual watermarking impact on the stationarity of audio signals. The study is based on stationarity indices, which represent a measure of variations in spectral characteristics of signals, using time-frequency representations. Simulation results with two kinds of signals, artificial signals and audio signals (speech and music), are presented. Stationarity indices comparison between water- marked and original audio signals shows a significant stationarity enhancement of the watermarked signal, especially for transient attacks. [ABSTRACT FROM AUTHOR]

The article discusses the highlights of the 2004 Micro-37 conference in the United States. The main thing that any conference must get right is the paper selection process. The issue is addressed by organizing committees that are in charge of issuing the call for papers and receiving enough submissions to make the event worth holding. Furthermore, it is also recognized that the most important aspect of the conference is its finances for events after the formal presentations that needed the expertise of someone with retail experience to plan the markdowns. Overall, the Micro-37 had a favorable outcome and the organizing committee got many thanks and congratulations for the after-dinner entertainment and activities it provided.

Each year, billions of dollars are spent by U.S. manufacturers to acquire hard and soft manufacturing technologies. Hard technologies are bundle of equipment, computer hardware and software such as computer numerical control, computer-aided manufacturing, robots, etc. In contrast, soft technologies are manufacturing techniques and know-how such as just-in-time, total quality management, statistical quality control, etc.--hardware is not essential to their successful use but can enhance their scope and effectiveness. This large empirical study of 1042 U.S. manufacturing plants develops a model to study the impact of manufacturing technology use on various performance measures; this study provides first evidence from the field that soft manufacturing technologies have many times the measurable effects of hard technologies on product, process, and business performance. Further, the effects of technology use are enhanced by the skilled use of technology. Implications for research and public policy are addressed. This paper has found that, in the opinion of top management in manufacturing firms, soft technologies have an impact on 1) shop floor performance; 2) product line breadth; and 3) growth and profitability. These finding should make the investment in soft technologies easier to justify. If top management controls the purse, and if it sees a link between investment in soft technology and tangible benefits in these three areas, getting top management to invest in soft technology should be easier. Before deciding on requests for investments in soft technologies, we hope top managers would seriously consider the findings of this paper. [ABSTRACT FROM AUTHOR]

The National Institute of Standard and Technology (NIST) is developing single-crystal reference materials for use as critical dimension (CD) reference materials. In earlier work, the reference features on these reference materials have been in the device layer of a silicon-on-insulator (SOI) wafers, with the buried oxide providing electrical isolation. This paper describes a new method of Slating the structures from the substrate by mews of a pn junction. The junction isolation technique is expected to provide several advantages over the SOI technique Including minimal susceptibility to charging when imaged in a CD scanning electron microscope (CDSEM), better edge quality, and ease of manufacture. Primary calibration of these reference materials is by imaging the cross-section of the feature with high-resolution transmission electron microscopy (HRTEM) at sufficiently high energy to resolve and count the individual lattice planes while electrical test structure metrology techniques provide the transfer calibration. Secondary calibration is performed with electrical test structure metrology, supplemented by visual techniques to verify that the features meet uniformity requirements. In this paper, we describe results for determining the electrical critical dimensions of these junction-isolated structures. This measurement and data analysis technique is a unique combination of the short-bridge variation of the cross-bridge resistor and the multi-bridge structure. [ABSTRACT FROM AUTHOR]

In this paper, we consider the problem of obtaining a reduced-dimension parameterization of a propagation medium for the purpose of estimating the medium from transmission data. The application addressed is microwave remote sensing of tropospheric index-of-refraction profiles over the sea surface, using radar clutter returns. The proposed parameterization balances the desire to represent features prominent in the a priori statistics of the profiles versus the need to capture elements of the profile that significantly affect the observed clutter data. In linear estimation problems, basis vectors for the unknown parameter vector that optimizes this tradeoff have been derived as the reduced-rank Wiener filter or, equivalently, the generalized Karhunen-Loeve transform (GKLT). In this paper, we reinterpret the linear result, producing an extension to the nonlinear refractivity estimation problem. The resulting procedure produces basis vectors for tropospheric refractivity that are less dependent on features that have little effect on the clutter measurements. This results in a more efficient parameterization and reduces mean-square estimation error relative to an approach driven purely by the statistical prior. Application of the generalized KL technique to finding efficient basis vectors for refractivity profiles taken off the southern California coast is presented. [ABSTRACT FROM AUTHOR]

Faculty in the College of Engineering at the University of Alabama developed a multidisciplinary course in applied spectral analysis that was first offered in 1996. The course is aimed at juniors majoring in electrical, mechanical, industrial, or aerospace engineering. No background in signal processing or Fourier analysis is assumed; the requisite fundamentals are covered early in the course and followed by a series of laboratories in which the fundamental concepts are applied. In this paper, a laboratory module on fault detection in rolling element bearings is presented. This module is one of two laboratory modules focusing on machine condition monitoring applications that were developed for this course. Background on the basic operational characteristics of rolling element bearings is presented, and formulas given for the calculation of the characteristic fault frequencies. The shortcomings of conventional vibration spectral analysis for the detection of bearing faults is examined in the context of a synthetic vibration signal that students generate in MATLAB. This signal shares several key features of vibration signatures measured on bearing housings. Envelope analysis and the connection between bearing fault signatures and amplitude modulation/demodulation is explained. Finally, a graphically driven software utility (a set of MATLAB m-files) is introduced. This software allows students to explore envelope analysis using measured data or the synthetic signal that they generated. The software utility and the material presented in this paper constitute an instructional module on bearing fault detection that can be used as a stand-alone tutorial or incorporated into a course. [ABSTRACT FROM AUTHOR]

As the number of combined-cycle units increases, efficient modeling approaches for these units play important roles for independent system operators (ISOs). Based on various combinations of combustion turbines (CTs) and steam turbines (STs), the combined-cycle unit could work at different configurations (modes) with different efficiencies. In this paper, we propose an edge-based formulation for the combined-cycle units in the unit commitment problem to improve the accuracy and effectiveness of current modeling approaches. Our formulation can 1) clearly describe the transition processes among different configurations so as to satisfy the ISO financial offer submission requirements and (2) capture physical constraints of each turbine, including the exact min-up/down time and time dependent startup cost, in the combined-cycle units so as to increase the operational flexibility while ensuring system feasibility. This model fits well with the current U.S. deregulated electricity market. The final numerical studies show that our approaches perform better than the current configuration-based modeling approach. [ABSTRACT FROM AUTHOR]

Underground coal mines in the United States of America are required to install lifeline (LL) cable inside escapeways to guide miners out of a mine when visibility becomes poor due to heavy smoke. Some LLs consist of single or multiple steel conductors covered with a protective plastic outer layer. Research has shown that this type of LL can be a good conductor to guide a medium-frequency (MF) communication system signal to travel over large distances. To understand the MF propagation characteristics of an LL, National Institute for Occupational Safety and Health researchers took measurements on a section of LL in a coal mine, and obtained propagation parameters for analysis. The measurement data show that MF signals have a low attenuation which can enable the use of an LL for communication throughout a mine. The propagation parameters measured are presented in this paper. [ABSTRACT FROM AUTHOR]

Buildings account for nearly 40 percent of the total energy consumption in the United States. As a critical step toward smart cities, it is essential to intelligently manage and coordinate the building operations to improve the efficiency and reliability of overall energy system. With the advent of smart meters and two-way communication systems, various energy consumptions from smart buildings can now be coordinated across the smart grid together with other energy loads and power plants. In this paper, we propose a comprehensive framework to integrate the operations of smart buildings into the energy scheduling of bulk power system through proactive building demand participation. This new scheme enables buildings to proactively express and communicate their energy consumption preferences to smart grid operators rather than passively receive and react to market signals and instructions such as time varying electricity prices. The proposed scheme is implemented in a simulation environment. The experiment results show that the proactive demand response scheme can achieve up to 10 percent system generation cost reduction and 20 percent building operation cost reduction compared with passive demand response scheme. The results also demonstrate that the system cost savings increase significantly with more flexible load installed and higher percentage of proactive customers participation level in the power network. [ABSTRACT FROM AUTHOR]

Secondary or low-voltage (LV) networks are applied in many large cities throughout the U.S., and in some other countries. Various grounding schemes have been employed for the primary systems supplying these secondary networks. In this paper, characteristics of the different grounding schemes for the substation and primary feeders that supply the LV networks are reviewed. The impacts of primary system grounding on the ground fault currents, the unfaulted line-to-ground voltages, as well as the voltage sags in the LV network have been considered for the single line-to-ground fault on the primary. The differences between systems with network transformers having the delta- or grounded-wye-connected primary windings are discussed. The relationships between grounding characteristics and protection settings, including actual examples, have been documented. [ABSTRACT FROM AUTHOR]

In this paper, we analyze how carbon emissions affect the selection of transportation modes and social welfare by using a two-stage Stackelberg gaming model. Based on this model, the government’s optimal carbon-emission tax scheme and the company’s optimal transportation mode and production decisions are explored. We find that: 1) whether or not the transport carbon-emission tax can increase social welfare depends on the relationships among the social cost of carbon (SCC), the transportation mode shifting threshold (TMST), and the biggest carbon-emission tax that a company can afford (BCRA); 2) a greater SCC implies a higher probability of improving social welfare via imposing transportation carbon-emission tax; and 3) a smaller TMST or BCRA yields a higher probability of improving social welfare when a carbon-emission tax is imposed. Further study shows that imposing a carbon-emission tax on the product with a higher production cost, a bigger product volume, or a bigger product density can increase the probability of improving social welfare. [ABSTRACT FROM PUBLISHER]

Understanding of software costs is important because of the overall magnitude of these costs (in 1985, roughly $70 billion per year in the U.S. and over $140 billion per year worldwide) and the fundamental impact software will have on our future quality of life. Section I of this paper discusses these issues. Section II, the main portion of the paper, discusses the two primary ways of understanding software costs. The "black-box" or influence-function approach provides useful experimental and observational in- sights oh the relative software productivity and quality leverage of various management, technical, environmental, and personnel options. The "glass-box" or cost distribution approach helps identify strategies for integrated software productivity and quality improvement programs, via such structures as the value chain and the software productivity opportunity tree. The individual strategies for improving software productivity identified in Section II are: • writing less code; • getting the best from people; • avoiding rework; • developing and using integrated project support environments. Section It provides overall surveys of early and recent progress along these and other lines identified by the opportunity tree. Better understanding of software costs leads to better methods of controlling software project costs, and vice versa. Section III discusses these issues. It points out that a good framework of techniques exists for controlling software budgets, schedules, and work completed, but that a great deal of further progress is needed to provide an overall set of planning and control techniques covering software product qualities and end-user system objectives. [ABSTRACT FROM AUTHOR]

Interconnection wide electric transmission system has been envisioned to facilitate the growth of renewable energy, enhance reliability, improve system operating efficiency, and reduce emissions. In this paper, we propose an explicit planning approach for transmission design at the national level. It has been applied to the U.S. system to design transmission overlays for multiple future generation scenarios. Associated simulation results suggest that a national transmission overlay provides economic, environmental, and system performance benefits. [ABSTRACT FROM PUBLISHER]

FERC Order 755 requires each RTO/ISO to use market-based mechanisms to select and compensate frequency regulation resources based on a two-part payment methodology, i.e., a capacity payment to keep the capacity in reserve and a performance payment to reflect the amount of work each resource performs in real-time in response to the system operator's dispatch signal. This paper discusses how MISO enhanced its market rules to implement a market-based regulation performance payment. The market enhancement includes four key areas: quantifying the movement of regulation, modifications to the market clearing processes, performance accuracy measurement, and performance-based two-part regulation compensation. [ABSTRACT FROM PUBLISHER]

U.S. hospitals are confronted with challenges of increasing service volume demand and inequitable payment by different private payers. Under this circumstance, budgeting the medical service volume efficiently and allocating the volume among private payers strategically becomes very important. Our paper proposes a hospital service volume assignment model to provide feasible solutions for hospitals. We develop our base model in the radiology department that provides comparatively homogenous medical service and involves high fixed cost. Under the fee-for-service payment schedule, the base model suggests that the hospital contracting decision with a private payer (insurance company) depends on an intuitive critical ratio. The critical ratio measures the tradeoff between the outsourcing cost generated from the actual service volume in excess of the capacity and the idling cost generated from the actual service volume below the capacity. Besides the base model, we explore two model extensions. First, we examine the criteria to budget the service volume above or below the service volume capacity. Second, we include the processing cost in the cooperation of the hospital and the insurance company. Efficient algorithms are presented for all models. Our findings provide managerial insight on hospital service volume budgeting decision by incorporating inequitable payment information. [ABSTRACT FROM PUBLISHER]

The use of alternate fuels and raw materials in the cement manufacturing process has evolved substantially over the last two to three decades, along with approaches to acquire regulatory approval. Most recently, the Environmental Protection Agency (EPA) has published new regulations as an overlay to what has been in place, having the potential to significantly impact this practice. Instead of dealing with the state agencies that usually have permitting authority, the new rules add another layer of regulatory hurdles by EPA. The new regulations also force a more significant overlap of the air permitting and solid waste rules. As a result, implementing an alternate material program and seeking approval has the potential to be considerably more challenging for the regulated community, in addition to adding complexity for the state agency permitting staff. This paper provides an update on the latest solid waste and air regulations applicable to alternative material use in cement plants, and potential implications for the U.S. industry. Early experiences will be explored, in addition to contemplating potential permitting and/or approval pathways expected to be encountered with the newest regulations in place. [ABSTRACT FROM AUTHOR]

A shortage of U.S. trained power and energy engineers has been predicted in the near future. One approach to solve this problem involves increasing the number of students choosing to study engineering, especially by exposing more students to engineering at an early age, even before high school. This paper presents the curricula and assessment of two summer programs for middle and high school students. We introduced electric and renewable energy concepts, engineering design, and MicroGrid related projects to the students. The survey results indicate that both programs improved students' levels of engineering knowledge, interest in learning and participating in engineering projects, and their intention to choose an engineering career; however, students' confidence in succeeding in engineering or science did not show improvement, which may impact students' willingness to choose engineering as a major. A positive attitude towards engineering among high school students had improved after the program but not among the middle school group. Improving the image of electrical engineering in general, and power systems engineering in particular, remains a challenge. [ABSTRACT FROM PUBLISHER]

Common cause events are those specific groups of dependent events that might adversely affect the operation of a redundant system. Common cause failures (CCF) are considered a subset of dependent failures with a major difference that they cannot be explicitly modeled. A CCF is a single point of failure (SPOF) causing a unit and its “perceived” redundant unit to fail simultaneously. During the first few years of commercial nuclear power plant operations, many probability risk assessment (PRA) studies revealed that CCF have significantly contributed to core damages. Consequently, the U.S. Nuclear Regulation Commission (NRC) initiated various CCF analyses in the 1980s. Since then, CCF analyses have been synonymous with nuclear facilities, and a majority of CCF analysis efforts have rightfully been focused on the safety of nuclear plants. Given that many industrial and commercial mission-critical facilities and high-reliability organizations now require a high degree of availability, therefore, CCF cannot be ignored. The objectives of this paper are to present 1) the importance of considering CCF in reliability, availability, and maintainability (RAM) analysis for industrial and commercial mission-critical facilities and high-reliability organizations, 2) simple quantitative analysis methods of CCF for industrial and commercial mission-critical facilities, and 3) the need for including CCF as part of future failure data collection efforts. [ABSTRACT FROM AUTHOR]

In a recent paper, Leroux compared three satellite soil moisture data sets (SMOS, AMSR-E, and ASCAT) and ECMWF forecast soil moisture data to in situ measurements over four watersheds located in the United States. Their conclusions stated that SMOS soil moisture retrievals represent “an improvement [in RMSE] by a factor of 2-3 compared with the other products” and that the ASCAT soil moisture data are “very noisy and unstable.” In this clarification, the analysis of Leroux is repeated using a newer version of the ASCAT data and additional metrics are provided. It is shown that the ASCAT retrievals are skillful, although they show some unexpected behavior during summer for two of the watersheds. It is also noted that the improvement of SMOS by a factor of 2-3 mentioned by Leroux is driven by differences in bias and only applies relative to AMSR-E and the ECWMF data in the now obsolete version investigated by Leroux et al. [ABSTRACT FROM PUBLISHER]