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This paper examines the problem of quality-of-service group communications in a heterogeneous network, which consists of multiple mobile ad hoc networks attached to the backbone Internet. A heuristic multicast algorithm named delay and delay variation multicast algorithm (DDVMA) is proposed. DDVMA is designed for solving the delay- and delay-variation-bounded multicast tree problem, which has been proved to be NP-complete. It can find a multicast tree satisfying the multicast end-to-end delay constraint and minimizing the multicast delay variation. Two concepts, which can help the DDVMA achieve better performance in terms of multicast delay variation than the delay and delay variation constraint algorithm that is known to be the most efficient so far, are proposed, namely, 1) the proprietary second shortest path and 2) the partially proprietary second shortest path. An analysis is given to show the correctness of DDVMA, and simulations are conducted to demonstrate the performance improvement of DDVMA in terms of multicast delay variation. It is also shown that the strategy employed by DDVMA is also applicable to handling the mobility of mobile hosts in a heterogeneous network. [ABSTRACT FROM AUTHOR]

Energy-efficient routing is a critical problem in multihop wireless networks due to the severe power constraint of wireless nodes. Despite its importance and many research efforts toward it, a distributed routing algorithm that maximizes network lifetime is still missing. To address this problem, this paper proposes a novel utility-based nonlinear optimization formulation to the maximum lifetime routing problem. Based on this formulation, a fully distributed localized routing algorithm is further presented, which is proved to converge at the optimal point, where the network lifetime is maximized. Solid theoretical analysis and simulation results are presented to validate the proposed solution. [ABSTRACT FROM AUTHOR]

Energy constraints have a significant impact on the design and operation of wireless sensor networks. This paper investigates the base station (BS) selection (or anycast) problem in wireless sensor networks. A wireless sensor network having multiple BSs (data sink nodes) is considered. Each source node must send all its locally generated data to only one of the BSs. To maximize network lifetime, it is essential to optimally match each source node to a particular BS and find an optimal routing solution. A polynomial time heuristic is proposed for optimal BS selection and anycast via a sequential fixing procedure. Through extensive simulation results, it is shown that this algorithm has excellent performance behavior and provides a near-optimal solution. [ABSTRACT FROM AUTHOR]

One of the main characteristics of wireless ad hoc networks is their node-centric broadcast nature of communication, leading to interferences and spatial contention between adjacent wireless links. Due to such interferences, pessimistic concerns have been recently raised with respect to the decreasing network capacity in wireless ad hoc networks when the number of nodes scales to several orders of magnitude higher. Such studies assume uniformly distributed nodes in the network and randomized traffic patterns. In this paper, we argue that in all cases of end-to-end data communications—including one-to-k unicast and multicast data dissemination as well as/c-to-one data aggregation—the maximum achievable end-to-end data throughput (measured on the sources) heavily depends on the strategy of arranging the topology of transmission between sources and destinations, as well as possible per-node operations such as coding. An optimal strategy achieves better end-to-end throughput than an arbitrary one. We present theoretical studies and critical insights with respect to how these strategies may be designed so that end-to-end throughput may be increased. After all, under all circumstances—in either a lightly loaded or a congested network—increasing end-to-end throughput from its baseline is always beneficial to applications using ad hoc networks to communicate. [ABSTRACT FROM AUTHOR]

Joint scheduling and power control schemes have previously been proposed to reduce power dissipation in wireless ad hoc networks. However, instead of power consumption, throughput is a more important performance concern for some emerging multihop wireless networks, such as wireless mesh networks. This paper examines joint link scheduling and power control with the objective of throughput improvement. The MAximum THroughput link Scheduling with Power Control (MATH-SPC) problem is first formulated and then a mixed integer linear programming (MILP) formulation is presented to provide optimal solutions. However, simply maximizing the throughput may lead to a severe bias on bandwidth allocation among links. To achieve a good tradeoff between throughput and fairness, a new parameter called the demand satisfaction factor (DSF) to characterize the fairness of bandwidth allocation and formulate the MAximum Throughput fAir link Scheduling with Power Control (MATA-SPC) problem is defined. An MILP formulation and an effective polynomial-time heuristic algorithm, namely, the serial linear programming rounding (SLPR) heuristic, to solve the MATA-SPC problem are also presented. Numerical results show that bandwidth can be fairly allocated among all links/flows by solving the MILP formulation or by using the heuristic algorithm at the cost of a minor reduction of network throughput. In addition, extensions to end-to-end throughput and fairness and multiradio wireless multihop networks are discussed. [ABSTRACT FROM AUTHOR]

A network of sensors can be used to obtain state-based data from the area in which they are deployed. To reduce costs, the data, sent via intermediate sensors to a sink, are often aggregated (or compressed). This compression is done by a subset of the sensors called ‘aggregators.’ Inasmuch as sensors are usually equipped with small and unreplenishable energy reserves, a critical issue is to strategically deploy an appropriate number of aggregators so as to minimize the amount of energy consumed by transporting and aggregating the data. In this paper, the authors first study single-level aggregation and propose an Energy-Efficient Protocol for Aggregator Selection (EPAS) protocol. Then, they generalize it to an aggregation hierarchy and extend EPAS to Hierarchical EPAS. The optimal number of aggregators with generalized compression and power-consumption models was derived, and fully distributed algorithms for aggregator selection were presented. Simulation results show that the algorithms significantly reduce the energy consumption for data collection in wireless sensor networks. Moreover, the algorithms do not rely on particular routing protocols and are thus applicable to a broad spectrum of application environments. [ABSTRACT FROM AUTHOR]

Utilities have long struggled with establishing re- source planning criteria that ensure adequate resources to meet loads at low cost. Historically, many utilities used planning reserve margin criteria. The onset of deregulation brought about a paradigm shift in which it was expected that markets would provide a more efficient mechanism for maintaining resource sufficiency in the course of system demand growth. Major power shortages in the Midwest and California in the wake of deregulation led to a reexamination by most regions of the need for centralized resource planning and integrated resource plans. Reserve margin techniques continue to be used by many resource planners to ensure resource adequacy. Simulation-based probabilistic assessments can provide a more direct measure of adequacy but are quite intensive computationally and therefore only allow exploring a limited number of scenarios. In this paper, we suggest a simple analytical probabilistic approach to maintaining resource adequacy and calculating peak load carrying capability of incremental generating units. The methodology targets a level of system adequacy, rather than a specified reserve margin, under system expansion. It provides. a powerful technique for simply calculating probability-based load carrying capability of resource additions without iteratively running computationally intensive stochastic computer models. The technique also provides a simple but effective method for developing portfolios of resources with comparable contributions to system adequacy. The latter may be employed in capacity expansion algorithms as a simpler, more efficient, and more accurate method of determining least-cost resource additions than targeting planning reserve margins. Applications of these techniques to the IEEE Reliability Test System illustrate the methods and verify the results with a stochastic model. [ABSTRACT FROM AUTHOR]

Deregulated electricity markets use an auction mechanism to select offers and their power levels for energy and ancillary services. A settlement mechanism is then used to deter- mine the payments resulting from the selected offers. Currently, most independent system operators (ISOs) in the United States use an auction mechanism that minimizes the total offer costs but determine payment costs using a settlement mechanism that pays uniform market clearing prices (MCPs) to all selected offers. Under this setup, the auction and settlement mechanisms are inconsistent since minimized costs are different from payment costs. Illustrative examples in the literature have shown that for a given set of offers, if an auction mechanism that directly minimizes the payment costs is used, then payment costs can be significantly reduced as compared to minimizing offer costs. This observation has led to discussions among stakeholders and policymakers in the electricity markets as to which of the two auction mechanisms is more appropriate for ISOs to use. While methods for minimizing offer costs abound, limited approaches for minimization of payment costs have been reported. This paper presents an effective method for directly minimizing payment costs. In view of the specific features of the problem including the nonseparability of its objective function, the discontinuity of offer curves, and the maximum term in defining MCPs, our key idea is to use augmented Lagrangian relaxation and to form and solve offer and MCP subproblems by using the surrogate optimization framework. Numerical testing results demonstrate that the method is effective, and the resulting payment costs are significantly lower than what are obtained by minimizing the offer costs for a given set of offers. [ABSTRACT FROM AUTHOR]

Transmissions from ground-based systems in C- and X-bands present a significant challenge to the use of these bands for passive microwave remote sensing from aircraft and satellites. Because future missions plan to continue to use these frequencies, it is important to characterize and understand the nature of interference in as much of the candidate spectrum as possible. This paper presents a statistical analysis of interference observed in the continental U.S. using six months of data collected from the C- and X-band channels of the WindSat microwave radiometer. Our findings are consistent with those of previous studies by Li et a!. and Njoku et aL, which are based on data obtained from the Advanced Microwave Scanning Radiometer-EOS using somewhat similar center frequencies and bandwidths. Results show significant radio-frequency interference (RFI) at C-band, including brightnesses in horizontal and vertical polarizations in excess of 330 K, while X-band RFI is less obvious through direct examination of measured linearly polarized brightnesses. Evidence of lower levels of RFI is provided through use of the spectral and polarization indexes of Li et a!., which reveal likely RFI contributions at X-band as well. Further confirmation of X-band RFI is obtained through analysis of the polarimetric channels, which are shown to provide direct evidence of RFI in contrast to the linearly polarized channels. A temporal analysis of the largest C-band RFI sources is also provided in an attempt to further understand their properties. [ABSTRACT FROM AUTHOR]

Referring received signal strength (RSS) to a signal propagation model to find user location is one of the most promising strategies in wireless communications. This paper develops a simple method based on relative signal-strength measurements, that is, the differences in stationary signal strength measured at the user location from multiple base transceiver stations (BTSs). The stationary signal strength is the averaged RSS and also is a stationary Gaussian process. In using this method, it is vitally important to confirm that some uncertain propagation parameters can be canceled out while a signal propagation model is merged into our method for locating users. In this way, the differences in stationary signal strength lead to two solutions: One is the distance difference between pairs of BTSs, and the other is the distances from the user location to the multiple BTSs. Consequently, the hyperbolic positioning algorithm due to the distance-difference solution and the circular positioning algorithm due to the distances solution can be presented, respectively. Afterward, some experimental results were drawn from a field trial in a real propagation environment. Results show that the hyperbolic and circular positioning algorithms can locate the user to within about 350 and 300 m in 67 percentile, respectively. Compared with the numerical result reported in the literature on existing methods based on RSS only, our method is superior. Despite the result not meeting Federal Communications Commission (FCC) requirements, this method proved to be sufficiently simple and efficient in terms of the computation at burden and network signaling load. [ABSTRACT FROM AUTHOR]

Microwave engineering often involves extensive circuit analysis and design, typically requiring precise calculations. To expedite the handling of complicated design calculations, a Web-based design tool named Microwave Engineering Solutions (MES) was developed as a graduate student project in the Electrical and Computer Engineering Department at North Dakota State University (NDSU), Fargo, and is described in this paper. JavaScript, PHP, and Perl were used to develop MES, which consists of three design tools: 1) FilTech—a design tool for analog filters, 2) LMatch—a design tool for impedance matching, and 3) MicroLines—a design tool for striplines and microwave network analysis. MES is used by Electrical and Computer Engineering (ECE) students studying various aspects of electromagnetics and is freely available on the Web via the link at http://venus.ece.ndsu.nodak.edu/∼ronelson/MESLink/index.html. [ABSTRACT FROM AUTHOR]

The course of Electric Machinery has been one of the core courses in the Electrical Engineering (EE) curriculum at Texas A&M University—Kingsville (TAMUK). In the past, the course was designed to focus mainly on topics of transformers and electric machines and was typically presented under the assumption of steady-state conditions. Unfortunately, many students considered the course old-fashioned and unexciting, and this lack of interest, in turn, seriously limited their ability to understand and appreciate the wide-ranging applications of electric machines. More important, electric machines today have become widely integrated with power electronics, digital signal processing (DSP), and digital control technology. However, these technological changes were not adequately reflected in the traditional teaching structure of the course. This paper presents a new approach that, by integrating computer-assisted teaching methodology in classroom presentation, substantially restructures the course so that it provides a comprehensive treatment of electric-drive systems with discussions covering electric machines, power electronic converters, feedback controls, power supply systems, and mechanical systems. [ABSTRACT FROM AUTHOR]

Epilepsy is the most prevalent neurological disorder affecting both adults and children. Over two-and-one-half million individuals in the United States have epilepsy and 25% of them do not respond to drugs. A significant focus of current research efforts is the development of a fully implantable device for real-time seizure detection and automated warning and blockage of seizures. The purpose of this paper is to describe and demonstrate the feasibility of incorporating a novel tool, the percentile tracking filter into a successful, validated seizure detection algorithm to create an analog seizure detection device. We demonstrate, in a small-scale study, that the performance of this analog implementation is statistically similar to a digital implementation of a previously described and successfully validated seizure digital algorithm. This analog implementation can be realized into an application specific integrated circuit that is suitable for a fully implantable device for seizure monitoring, warning and treatment, which is likely to consume very little power, a feature of practical value. [ABSTRACT FROM AUTHOR]

The U.S. Navy is looking for methods to maximize the survivability of combat ships during battle conditions. A shipboard power distribution system is a stiff isolated power system that is vulnerable to voltage sags, which arise due to faults or pulsed loads, which can cause interruptions of critical loads. A series voltage injection type flywheel energy storage system (FESS) is used to mitigate voltage sags and maximize the survivability of the ship. The basic circuit consists of an energy storage system, power electronic interface, and a series injection transformer. In this case, the energy storage system consists of a flywheel coupled to an induction machine. The stored energy is used for sag correction for the critical load. Indirect field-oriented control (IDFOC) with space-vector pulsewidth modulation (SVPWM) is used to control the induction machine. Sinusoidal PWM is used for controlling the power system side converter. This paper presents the modeling, simulation, and analysis of a FESS with a power converter interface using PSCADIEMTDC. [ABSTRACT FROM AUTHOR]

This Transactions’ Mini-Special Issue includes a selection of papers presented last year at the 2018 IEEE Radio Frequency Integrated Circuits (RFIC) Symposium held in the Pennsylvania Convention Center and Loews Philadelphia Hotel, Philadelphia, PA, USA, during June 10–12, 2018. The 2018 RFIC Symposium focused on the major themes of millimeter-wave 5G and autonomous vehicles in the plenary sessions. The first plenary talk was delivered by Zachary J. Lemnios, the Vice President of IBM Research, and discussed silicon-based mm-wave systems for 5G and beyond. The second plenary talk was presented by Lars Reger, CTO of NXP Semiconductors’ Automotive Business Unit, and focused on RF systems in the automotive industry, including the technical aspects related to future self-driving cars. [ABSTRACT FROM AUTHOR]

We introduce new methods for increasing the performance of multiprogram digital audio broadcast systems, e.g., satellite digital audio broadcasting. Joint multiprogram encoding is an attractive possibility for parallel broadcasting of a large number of programs. Joint coding extended over multiple audio frames in time give further improvements. The benefits of this kind of statistical multiplexing yield improved audio quality and/or higher capacity in terms of number of programs. We describe the new Joint Multiple Program Encoding Technique in the context of the perceptual audio coding (PAC) type of algorithms. We also describe methods for multi-program transmission including Equal Error Protection (EEP) as well as Unequal Error Protection (UEP) and improved error concealment for multiple program transmission. Some of the techniques described in this paper, are currently being used in satellite digital audio broadcasting in the United States. [ABSTRACT FROM AUTHOR]

Prostatic adenocarcinoma is the most commonly occurring cancer among men in the United States, second only to skin cancer. Currently, the only definitive method to ascertain the presence of prostatic cancer is by trans-rectal ultrasound (TRUS) directed biopsy. Owing to the poor image quality of ultrasound, the accuracy of TRUS is only 20%-25%. High-resolution magnetic resonance imaging (MRI) has been shown to have a higher accuracy of prostate cancer detection compared to ultrasound. Consequently, several researchers have been exploring the use of high resolution MRI in performing prostate biopsies. Visual detection of prostate cancer, however, continues to be difficult owing to its apparent lack of shape, and the fact that several malignant and benign structures have overlapping intensity and texture characteristics. In this paper, we present a fully automated computer-aided detection (CAD) system for detecting prostatic adenocarcinoma from 4 Tesla ex vivo magnetic resonance (MR) imagery of the prostate. After the acquired MR images have been corrected for background inhomogeneity and nonstandardness, novel three-dimensional (3-D) texture features are extracted from the 3-D MRI scene. A Bayesian classifier then assigns each image voxel a "likelihood" of malignancy for each feature independently. The "likelihood" images generated in this fashion are then combined using an optimally weighted feature combination scheme. Quantitative evaluation was performed by comparing the CAD results with the manually ascertained ground truth for the tumor on the MRI. The tumor labels on the MR slices were determined manually by an expert by visually registering the MR slices with the corresponding regions on the histology slices. We evaluated our CAD system on a total of 33 two-dimensional (2-D) MR slices from five different 3-D MR prostate studies. Five slices from two different glands were used for training. Our feature combination scheme was found to outperform the individual texture features, and also other popularly used feature combination methods, including AdaBoost, ensemble averaging, and majority voting. Further, in several instances our CAD system performed better than the experts in terms of accuracy, the expert segmentations being determined solely from visual inspection of the MRI data. In addition, the intrasystem variability (changes in CAD accuracy with changes in values of system parameters) was significantly lower than the corresponding intraobserver and interobserver variability. CAD performance was found to be very similar for different training sets. Future work will focus on extending the methodology to guide high-resolution MRI-assisted in vivo prostate biopsies. [ABSTRACT FROM AUTHOR]

Industrial distribution systems have been designed in the USA, considering prevalent standards, i.e., American National Standards Institute (ANSI), IEEE, National Electrical Code (NEC), Occupational Safety and Health Administration (OSHA), etc., and arc flash was not a consideration for designing electrical power systems in the industry. Functionality and economics were the important factors, and will always be so. However, the arc flash analysis and limiting the incident energy will usher a new parameter in system design. It can be demonstrated that in many current installations and new installations designed without considerations of limiting the arc flash energy, the hazard risk category exceeds the highest Class 4 personal protective equipment (PPE), i.e., an arc thermal performance exposure value (ATPV) of 40 cal/cm². This paper discusses typical industrial distribution systems at low-voltage and medium-voltage levels and demonstrates the impact of system design decisions and protection on the incident energy and arc flash hazard reduction. [ABSTRACT FROM AUTHOR]

Since 1970, the U.S. National Highway Traffic Safety Administration (NHTSA) has been responsible for setting and monitoring traffic and safety standards for all motor vehicles on U.S. roads. Authorized by the National Traffic and Motor Vehicle Safety Act of 1966, the agency can investigate and recall any vehicle that contains a safety-related defect or is in violation of a federal motor vehicle safety standard. This paper describes the role of the NHTSA in assessing automotive electronics reliability and safety. We discuss the definition of "safety defect," and how it has been applied. In a number of defect investigations, automakers had initially led the NIITSA to believe that their vehicles were safe and complied with safety standards, although they contained potentially fatal defects. As a result, NHTSA had difficulty in taking effective action against rollovers, stalling problems, and fire hazards in some of the nation's popular vehicles, even though evidence pointed to a safety defect This article then describes a Juridical process that may improve road safety. Examples are given as to how regulations could be manipulated to stymie federal investigations, followed by an explanation of how the transportation Recall Enhancement, Accountability, and Documentation Act, passed in 2000, could facilitate more effective investigations. Finally, we discuss the economics of defect recalls, and provide some recommendations [ABSTRACT FROM AUTHOR]

The article assesses the collateral damage suffered by the United States on the wake of war on terrorism. The article reports that in the wake of the terrorist attacks of 2001, the United States government undertook a rushed effort to increase security. In addition to new legislation such as the Patriot Act and the Homeland Security Act of 2002, the government dramatically ramped up enforcement of laws. In response to the terrorist attacks of September 11, 2001, the U.S. government has already passed three major new laws in 2002. Another major change after these attacks are that the U.S. scientists and engineers now account for less than one-third of the world's scientific papers.

This paper presents a method for decomposing process-control systems. This decomposition method is automated, meaning that a series of principles that can be evolved to support automated tools are given to help a designer decompose complex systems into a collection of simpler components. Each component resulting from the decomposition process can be designed and implemented independently of the other components. Also, these components can be tested or verified by the end-user independently of each other. Moreover, the system properties, such as safety, stability, and reliability, can be mathematically inferred from the properties of the individual components. These components are referred to as IDEAL (lndependently Developable End-user Assessable Logical) components. This decomposition method is applied to a case study specified by the High-Integrity Systems group at Sandia National Labs, which involves the control of a future version of the Bay Area Rapid Transit (BART) system. [ABSTRACT FROM AUTHOR]

NASA conducts and funds research to advance the state of the art in aeronautics, including improvements in aircraft design leading to enhanced performance in areas such as noise, emissions, and safety. A particular initiative involves development of an all-electric aircraft requiring significant improvements in certain technologies. NASA has started a new project with one of the objectives being the development of enabling technologies for an all-electric aircraft. Electrical aeropropulsion requires the design of more compact and efficient electrical motors. In order to me crease the power density, the weight/size must be minimized and the air gap flux density must increase significantly the use of superconducting materials is an obvious choice. Existing HTS motors are proof-of-principle demonstrators and exhibit power densities lower than 1 HP/lb, which is too low to be considered in mobile systems. This paper deals with a preliminary electromagnetic design of a 200 HP high temperature superconducting motor optimized in terms of power density. The presented configuration is a synchronous motor with a nonconventional topology enhanced by HTS bulk material. The design targets the Cessna 172 propulsion requirements that are 200 HP at 2700 RPM. [ABSTRACT FROM AUTHOR]

Radio-frequency interference (RFI) is an increasingly serious problem for passive and active microwave sensing of the Earth. To satisfy their measurement objectives, many spaceborne passive sensors must operate in unprotected bands, and future sensors may also need to operate in unprotected bands. Data from these sensors are likely to be increasingly contaminated by RFI as the spectrum becomes more crowded. In a previous paper we reported on a preliminary investigation of RFI observed over the United States in the 6.9-GHz channels of the Advanced Microwave Scanning Radiometer (AMSR-E) on the Earth Observing System Aqua satellite. Here, we extend the analysis to an investigation of RFI in the 6.9- and 10.7-GHz AMSR-E channels over the global land domain and for a one-year observation period. The spatial and temporal characteristics of the RFI are examined by the use of spectral indices. The observed RI?! at 6.9 GHz is most densely concentrated in the United States, Japan, and the Middle East, and is sparser in Europe, while at 10.7 GHz the RFI is concentrated mostly in England, Italy, and Japan. Classification of RFI using means and standard deviations of the spectral indices is effective in identifying strong RFI. In many cases, however, it is difficult, using these indices, to distinguish weak RFI from natural geophysical variability. Geophysical retrievals using RFI-filtered data may therefore contain residual errors due to weak RFI. More robust radiometer designs and continued efforts to protect spectrum allocations will be needed in future to ensure the viability of spaceborne passive microwave sensing. [ABSTRACT FROM AUTHOR]

Research into transmission pricing and congestion management in interconnected power systems, such as those found in USA and Europe, requires an appropriate benchmark system to test different methodologies. Creation of a realistic benchmark system is difficult as utilities are often unwilling to disclose details of their own systems because of commercial sensitivity and security reasons. This paper presents development of an approximate model of a European interconnected system which could be used to study the effects of cross-border trades. In creating the load-flow model, only publicly available information was used. Comparison of simulation results conducted on the test system with the published cross-border flows and power transfer distribution factors showed a very good correlation, exceeding 90%. [ABSTRACT FROM AUTHOR]

This paper reviews the National Aeronautics and Space Administration (NASA)/Jet Propulsion Laboratory(JPL) CloudSat Extended Interaction Klystron requirements, design, performance, and development of a long life model for the European Space Agency (ESA)/Japan Aerospace Exploration Agency EarthCARE program plus Ka-band Extended Interaction Klystrons for the NASAIJPL Jupiter Icy Moons Orbiter and ESA European Global Precipitation Measurement Missions. [ABSTRACT FROM AUTHOR]

This paper studies an uneven two-class unsupervised classification problem of satellite imagery, i.e., the mapping of U.S. Department of Agriculture's (USDA) Conservation Reserve Pro- gram (CRP) tracts. CRP is a nationwide program that encourages farmers to plant long-term, resource conserving coven to improve soil, water, and wildlife resources. With recent payments of nearly US $1.6 billion for new enrollments (2002 signup), it is imperative to obtain accurate digital CRP maps for management and evaluation purposes. CRP mapping is a complex classification problem where both CRP and non-CRP areas are composed of various cover types. Two nonparametric machine learning approaches, i.e., decision tree classifier (DTC) and support vector machine (SVM5) are implemented in this work. Specifically, considering the importance of CRP classification sensitivity, a new DTC pruning method is proposed to increase recall. We also study two SVM relaxation approaches to increase recall. Moreover, a localized and parallel framework is suggested in order to efficiently deal with the large-scale CRP mapping need. Simulation results validate the applicability of the suggested framework and proposed techniques. [ABSTRACT FROM AUTHOR]

Technology for the 14- and 35-GHz Second-Generation Precipitation Radar (PR-2) is currently being developed by the National Aeronautics and Space Administration Jet Propulsion Laboratory to support the development of future spaceborne radar missions. PR-2 will rely on high-performance onboard processing techniques in order to improve the observation capabilities (swath width, spatial resolution, and precision) of a low-earth orbiting rainfall radar. Using field-programmable gate arrays (FPGAs), we have developed a prototype spaceborne processor and controller module that will support advanced capabilities in the PR-2 such as autotargeting of rain and compression of rainfall science data. In this paper, we describe the new technology components designed for the onboard processor, including an FPGA-based 40 × 109 op/s pulse-compression receiver/filter with a range sidelobe performance of -72 dB, and an adaptive scanning controller which yields a six-fold increase in the number of radar looks over areas of precipitation. [ABSTRACT FROM AUTHOR]

This paper describes a novel robotic end-effector and a method for grasping deformable objects with undefined shapes and geometry, such as sacks and bags. The first prototype end-effector, designed for applications in the U.S. Postal Service, is comprised of two parallel rollers with gripping surfaces in which the rollers are pushed toward each other. When the end-effector comes into contact with any portion of the deformable object, the rollers turn inwardly so that a graspable portion of the object is dragged between the rollers. The rollers stop rotating when a graspable portion of the material/object is caught in between, allowing the object to be maneuvered by the robot. The object is released when the rollers turn outwardly. The end-effector described in this article can grab and hold filled sacks from any point on the sack, regardless of the sack's orientation. Experimental evaluation of the end-effector has proven the design and implementation remarkably effective. This article describes the hardware, control method, and design issues associated with the end-effector. [ABSTRACT FROM AUTHOR]

Following the steps of the gas industry, the traditional paradigm of the vertically integrated electrical utility structure has begun to change. In the United States, the Federal Energy Regulatory Commission has issued several rules and Notices of Proposed Rulemaking to set the road map for the utility deregulation. The crisis in California has drawn great attention and sparked intense discussion within the utility industry. One general conclusion is to rejuvenate the idea of integrated resource planning and promote the distributed generation via traditional or renewable generation facilities for the deregulated utility systems. Fuel cell and photo- voltaic are the most promising renewable generation technologies for the residential and small commercial users. It is desirable for these facilities to be interconnected with the utility grid to perform peak shaving, demand reduction, and to serve as emergency and standby power supply. However, the mismatch between the utility tie protection and the equipment protection makes it impossible for the fuel cell and/or photovoltaic to serve as emergency and standby power supply when the utility supply is lost due to nearby external faults. To overcome this issue, this paper discusses the development of an integrated high-speed Intelligent utility tie monitoring, control, and protection system to replace the traditional tie breakers for those residential and small commercial facilities with disbursed/renewable generation facilities. [ABSTRACT FROM AUTHOR]

Digital Television (DTV) service has begun in all the major urban areas within the United States but has yet to significantly reach the rural areas. Often, translators are the only means of providing free, over-the-air television service to people living in these areas. One challenge is that while specific rules for operation and spectrum allocation have existed for quite some time for full-service stations in urban areas, rules for DTV translator stations in rural areas have just been created (September 2004). Another challenge is overcoming the scarcity of spectrum that exists under the old analog taboo interference rules. A key component in overcoming these challenges is to determine interference parameters in the form of desired-to-undesired (D/U) field strength ratios that will allow as many DTV and NTSC signals to co-exist as possible. Also, co-sited analog and digital translator sites utilizing low radiated power can be used for adjacent/taboo channel operation (NTSC next to DTV or DTV next to DTV) if careful engineering and planning are employed. Even first adjacent channel operation can be accomplished if proper effective radiated power (ERP) ratios are selected. This paper shows that a relative 10-dB NTSC-to-DTV power ratio and a relative 0-dB DTV-to-DTV power ratio is acceptable at a co-sited repeater site in order to avoid receiver interference among the co-sited signals. The choice of absolute radiated power levels depends on the desired coverage area, the surrounding terrain, and the required interference avoidance of potential weak signals from distant stations (if present). Co-siting repeaters and sharing as many of the common transmission elements as possible such as combiners, feedlines, broadband antennas, test equipment, etc. allow many low-power DTV and NTSC signals to be transmitted together under well-controlled conditions, thereby providing the most efficient use of scarce spectrum. Further independent Laboratory testing with current consumer DTV receivers is also vital for improved channel allocation planning. [ABSTRACT FROM AUTHOR]

Following in the steps of the gas industry, the traditional paradigm of the vertically integrated electric utility structure has begun to change. In the United States, the Federal Energy Regulatory Commission has issued several rules and Notices of Proposed Rulemaking to set the road map for the deregulated utility industry. The crisis in California has drawn great attention and sparked intense discussion within the utility industry. One general conclusion is to rejuvenate the idea of integrated resource planning and promote the distributed generation via traditional or renewable generation facilities for the deregulated utility systems. Wind generation is one of the most mature and cost-effective resources among different renewable energy technologies. Recently, several large-scale wind generation projects have been implemented in the U.S. and other parts of the world. Similar to other new generation facilities, the impacts of a large-scale wind generation on the system operation, voltage profile, and system security have to be investigated and studied. Remedies for possible operation issues have to be evaluated and implemented. This paper discusses the impact study of connecting a 120-MW wind farm into the transmission system of a utility company within the Southwest Power Pool. [ABSTRACT FROM AUTHOR]

Utilization voltages used on longwall equipment operating in coal mines in the United States have increased steadily over the past 15 years from 1000 up to 4160 V. This voltage in- crease has directly influenced the 200% gain in overall longwall productivity from 1987 to the present. The transition from medium voltage (661-1000 V) to high voltage (greater than 1000 V) has permitted significant increases in mining face widths and equipment sizes. Longwall systems with total connected loads of over 5000 hp are now common, and all longwalls in the United States now use high-voltage equipment, with the majority utilizing 4160 V. Shielded cables, which have significantly more capacitance than unshielded cables, are required for high-voltage applications in the mining industry. This capacitance can have detrimental influences on system overvoltages and relay selectivity during ground-fault conditions if the values for the neutral grounding resistor and the ground-fault-relay pickup settings are improperly chosen. These issues are addressed in this paper. [ABSTRACT FROM AUTHOR]

Impulse radio (IR) and especially time-hopping IR (TH-IR) systems have attracted considerable attention since their introduction in the context of ultra wideband (UWB) systems in the early 1990s. Recently, with the U.S. Federal Communications Commission actions allowing for the wide-spread use of UWB radio systems, the interest in these systems has grown further. These systems promise to deliver high data rates in multiple access communication channels with very simple transmitter and receiver designs. The importance of multiuser detection for achieving high data rates with these systems has already been established in several studies. This paper studies several low-complexity multiuser detectors specifically designed for TH-IR radio systems. It is demonstrated that many multiuser detectors developed primarily for direct-sequence code division multiple access (DSCDMA) systems can be used essentially without any change in TH-IR receivers. Further, several novel, low-complexity multiuser detectors that exploit the special signal structure used for transmission by TH-LR systems are developed. These novel detectors are analyzed both theoretically and via simulations. It is shown that a very simple iterative multiuser detector yields performance that is similar to that of a single-user system. [ABSTRACT FROM AUTHOR]

A pocket radiation detection system has been developed at the Idaho National Engineering and Environmental Laboratory for homeland security applications. It can detect both neutrons and gamma rays instantaneously. This sensor has been designed with an emphasis on compactness, recognizing the widespread need for a radiation detection instrument that could provide both neutron and gamma-ray detection in a single, portable unit. It is very small, extremely sensitive, versatile, and easy to operate. It can detect gamma rays and neutrons in a radiation field as tow as 10 μR/h above the ambient background, which makes it ideal for use in national security applications. The detection system is based on a technique of using a combination of two sensors made of lithium isotopes 6Li and 7Li. It operates on one rechargeable Li-ion battery and is small enough to be put in a pocket or clipped to a belt. In this paper, the detection technique used in developing this prototype sensor as well as its performance will be presented. [ABSTRACT FROM AUTHOR]

The facility that we developed for producing precision drift tubes of the ATLAS forward muon system is described in this paper. We have completed the production of approximately 30000 drift tubes in Seattle. The results of quality assurance for these tubes are presented. The drift tube assembly and quality assurance are two separation operations that proceed in parallel. The quality of the drift tube that we produced meets the very stringent requirements of the ATLAS experiment. The typical average production rate is 2 to 3 mm per tube and the rejection rate is less than 1.5%. [ABSTRACT FROM AUTHOR]

The transition radiation tracker (TRT) is one of the three subsystems of the inner detector of the ATLAS experiment. It combines electron identification capability with charged-particle track reconstruction. A total of 420 000 electronic channels provide continuous tracking with many projective measurements per track. This paper gives details of some features of the TRT, from performance requirements to the consequences of its operation in the LHC environment. Some technical choices and operating conditions have been recently changed, the most significant one being the active gas. Presently, a large fraction of barrel and end-cap modules have been assembled in the United States and Russia, respectively. A strict quality assessment has been implemented at the assembly sites and at CERN upon arrival of the modules. The acceptance tests include dimensional surveys, wire-tension measurements, gas-tightness tests, high-voltage training, and gas-gain uniformity measurements along each individual straw. First estimates of the module quality are presented based on the analysis of these tests. [ABSTRACT FROM AUTHOR]

Several information systems' and computer-mediated communication studies in the literature measure user's perceptions of email. The user's perceptions of email were used to develop and validate the Technology Acceptance Model (TAM). While a user's perceptions of email play an important role in literature, very few studies have focused solely on developing a construct for measuring these perceptions. In this paper, we develop a construct to measure an individual's perceptions of email as a medium for electronic communication in organizations. Using a survey of management and non management employees in Northeastern US, we empirically test our theoretical construct. The results of our research indicate that an individual's perceptions of email are a multidimensional construct with two dimensions: the individual level dimension and the organizational level. At an individual level, a person's perceptions may be impacted by email's role in improving productivity, supporting team work, and providing global reach. At an organizational level a person's perceptions may be impacted by email's role in making an organization vulnerable to viruses, exposing proprietary information, and/or encouraging unprofessional and illegal behavior. [ABSTRACT FROM AUTHOR]

The data acquisition system at the National Super- conducting Cyclotron Laboratory (NSCL), Michigan State University, East Lansing, is based on commodity PC components running an unmodified Linux kernel. A commercial PCI-VME bus bridge connects the readout processors of this system to digitization hardware. While Linux is not a real-time system, this paper shows how we have structurd the readout software to meet the requirements of the NSCL without the use of real-time or embedded components. [ABSTRACT FROM AUTHOR]

A significant banter to improving, the power quality at industrial facilities is the lack of contemporaneous and historical power quality and reliability data. A new Web-enabled near-real-time power quality and reliability monitoring system, termed 1-Grid, has been developed to provide such information on a nationwide basis. The ultralow-cost sensors record power events and send event data via the Internet to the system database servers using an internal modem. Data display, e-mail event notification, site administration, and summary reporting of the data are achieved via a Web browser. In cooperation with the U.S. Department of Energy, the Electric Power Research Institute, and leading utilities and manufacturers, the deployment of these sensors has begun, with a target deployment of 50 000 monitors across the U.S. and Canada over the next 2-4 years. This paper discusses the implementation of this grid information resource, and discusses data captured by the network since early monitors were deployed in 2001. [ABSTRACT FROM AUTHOR]

In the 1990's, there was a conscious drive to outsource much of the manufacturing in the U.S electronics industry. Initially the outsourcing was to contract manufacturers (those companies that assemble circuit boards and final products), mostly offshore and largely in China. Now, after the economic boom of the late 1990's, the engineering and technical jobs seem to be following manufacturing. Much of the world's commercial electronics are labeled "Made in China," and China now seems to be the only growing economy [1]. After decades of western technical innovation, why is this transfer occuring? Is loss of engineering jobs just another consequence of globalization? What does the future hold? This paper addresses the nature and cause of the trend, predicts the future and provides a prescription for the U.S. [ABSTRACT FROM AUTHOR]

This paper describes the identification of a common mold (i.e., fungus) growing on nonceramic insulators (NCIs) in service, and analyzes its impact on the electrical performance. The insulators evaluated were line posts removed from a 138-kV transmission line serving the interior (away from the coast) regions in Florida. The insulators had housings made from different types of silicone rubber (SR) and ethylene propylene rubber (EPR) polymer families. Electrical tests performed include surface resistance measurements and determination of contamination withstand capability (CWC) using the clean-fog procedure. Changes in the CWC were correlated to material changes by using micro-Fourier transform infrared (FTIR) analysis and surface resistance measurements. It was concluded that the mold growth is dependent on material formulation and outdoor environment. On SR insulators that exhibited mold growth, there was a reduction in the CWC when compared to the same insulator without the mold; however, even the reduced level of CWC was superior to that obtained on similarly rated EPR and porcelain insulators without any visible mold growth. Lastly, simple methods to remove the mold from the insulators are listed. [ABSTRACT FROM AUTHOR]

The Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E) was developed and provided to the National Aeronautics and Space Administration's EOS Aqua satellite by the National Space Development Agency of Japan, as one of the indispensable instruments for Aqua's mission. AMSR-E is a modified version of AMSR that was launched December 2002 aboard the Advanced Earth Observing Satellite-II (ADEOS-II). It is a six-frequency dual-polarized total-power passive microwave radiometer that observes water-related geophysical parameters supporting global change science and monitoring efforts. The hardware improvements over existing spaceborne microwave radiometers for earth imaging include the largest main reflector of its kind and addition of 6.925-GHz channels. These improvements provide finer spatial resolution and the capability to retrieve sea surface temperature and soil moisture information on a global basis. This paper provides an overview of the instrument characteristics, mission objectives, and data products. [ABSTRACT FROM AUTHOR]

IBOC DAB (In-Band On-Channel Digital Audio Broadcasting) requires the simultaneous broadcast of an analog and a digital signal within one channel of the FM band. Because broadcasters are adding IBOC to their existing systems, it is vital that they achieve maximum power efficiency while working within their existing space and power limitations. There are currently three different strategies proposed for accomplishing this goal, each having its own advantages and disadvantages. One strategy is to establish a separate, second antenna for the digital service. The other two strategies involve combining the analog and digital signals, either in a single hybrid transmitter or at the output of separate analog and digital transmitters. This paper discusses the equipment required for accomplishing this last strategy. [ABSTRACT FROM AUTHOR]

Focuses on the technical program presented at the 2001 Institute of Electrical and Electronics Engineers Microwave Theory and Techniques Society International Microwave Symposium in Phoenix, Arizona. Coverage of the technical program; Record on the number of paper submission; Citations on the topics in the symposium.

Focuses on the computer vision research for undergraduates in the United States. Ability of students to prepare and present papers in conferences; Accomplishments of students in journal publications; Continuance of students on graduate studies at various institutions.

This paper documents an application of the finite state model checker SPIN to formally analyze a multithreaded plan execution module. the plan execution module is one component of NASA's New Millennium Remote Agent, an artificial intelligence-based space-craft control system architecture which launched in October of 1998 as part of the DEEP SPACE 1 mission. the bottom layer of the plan execution module architecture is a domain specific language, named ESL (Executive Support Language), implemented as an extension to multithreaded COMMON LISP. ESL supports the construction of reactive control mechanisms for autonomous robots and space-craft. For this case study, we translated the ESL services for managing interacting parallel, goal-and-event driven processes into the PROMELA input language of SPIN. A total of five previously undiscovered concurrency errors were identified within the implementation of ESL. According to the Remote Agent programming team, the effort has had a major impact, locating errors that would not have been located otherwise and, in one case, identifying a major design flaw. In fact, in a different part of the system, a concurrency bug identical to one discovered by this escaped testing and caused a deadlock during an in-flight experiment 96 million kilometers from earth. The work additionally motivated the introduction of procedural abstraction in terms of inline procedures into SPIN. [ABSTRACT FROM AUTHOR]

This special collection of papers had its genesis at the IEEE Computer Society Workshop on Software Testing and Test Documentation held in Fort Lauderdale, Florida during December 18-20, 1978. This collection is devoted to selected papers on program testing that were presented at the Workshop. The thrust is towards approaches that can support the heuristic components of testing. There is increasing recognition that it is unlikely there will be a grand theory of testing which will lead to fully automated testing systems. Instead the tester will be called upon to use his intuition and problem-dependent knowledge in a discipline manner to test for a variety of specified error types. But it is crucial that this less ambitious, heuristic activity be nevertheless firmly embedded in an underlying framework which is logical, rigorous and well-understood.

Highlights the activities and topics discussed at the International Electrical and Electronics Engineering (IEEE) Microwave Theory and Techniques Society (MTTS) International Microwave Symposium held from June 13 to 19, 1999 in Anaheim, California. Guest speakers; Presentation of the IEEE Electromagnetics Award and the IEEE MTT-S 1999 IEEE Fellows; Scientific paper competition.

SDD-1, A System for Distributed Databases, is a distributed database system being developed by Computer Corporation of America (CCA), Cambridge, MA. SDD-1 permits data to be stored redundantly at several database sites in order to enhance the reliability and responsiveness of the system and to facilitate upward scaling of system capacity. This paper describes the method used by SDD-1 for updating data that are stored redundantly. Redundant updating can be costly because it may potentially involve extensive intercomputer communication overhead in order to lock all copies of data being updated. The method described here avoids this overhead by identifying cases in which it is not necessary to perform this global database locking. The identification of transactions that do not require global locking is based on a predefinition of transaction classes performed by the database administrator using an analysis technique described herein. The classes defined are used at run time to decide what level of synchronization is needed for a given transaction. It is important to note that this predefinition activity in no way limits the transactions that the system can accept; it merely permits more efficient execution of those types of transactions that were anticipated. [ABSTRACT FROM AUTHOR]

This paper describes methods for automatically analyzing formal, state-based requirements specifications for some aspects of completeness and consistency. The approach uses a low-level functional formalism, simplifying the analysis process. State-space explosion problems are eliminated by applying the analysis at a high level of abstraction; i.e., instead of generating a reachability graph for analysis, the analysis is performed directly on the model. The method scales up to large systems by decomposing the specification into smaller, analyzable parts and then using functional composition rules to ensure that verified properties hold for the entire specification. The analysis algorithms and tools have been validated on TCAS II, a complex, airborne, collision-avoidance system required on all commercial aircraft with more than 30 passengers that fly in U.S. airspace. [ABSTRACT FROM AUTHOR]