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This paper introduces an innovative concept for the use of multispectral stereo pair of satellite images to identify dangerous trees and plants along overhead transmission rights of way. Multispectral satellite images of the right of way are scanned automatically and the color (wavelength) of each pixel is analyzed. This scanning identifies healthy vegetation which may contain trees that endanger the line. Using multispectral stereo images, the height of each pixel is determined and the distance from the conductor is calculated. When this distance is less than the danger zone surrounding the conductors, the identified object or tree is assumed to endanger the line. Case studies using satellite images in the vicinity of Scottsdale, AZ and San Diego, CA demonstrate the feasibility of the proposed method. Details are given for prototype software development for satellite image scanning to determine tree interference with overhead transmission lines. [ABSTRACT FROM AUTHOR]

This paper focuses on the energy storage system and the power electronic interface included in microsources of the CERTS microgrid. CERTS stands for the Consortium for Electric Reliability Technology Solutions. The consortium was formed in 1999 to research, develop, and disseminate new methods, tools, and technologies to protect and enhance the reliability of the U.S. electric power system and efficiency of competitive electricity markets. To provide the plug-and-play feature and the power quality requirements of the CERTS microgrid, all microsources regardless of their prime mover type must have a unified dynamic performance. This necessitates attaching an energy storage module to some or all of the microsources. The storage module is attached to the prime mover through a power electronic interface that couples the microsource to the microgrid. Details of the energy storage module, the power electronic interface and the corresponding controls are described. Performance of an example microsource, which includes a synchronous generator, a storage module and an electronic interface, is studied. Dynamic performance of the example microsource when operating in the CERTS microgrid is evaluated based on digital time-domain simulations in the EMTP-RV software environment. Effectiveness of the storage module, the electronic interface and the corresponding controls in enhancing the microsource performance is verified. [ABSTRACT FROM AUTHOR]

High-temperature superconducting (HTS) cable systems are expected to be a solution for improvement of the power grid and three demonstration projects in the real grid are underway in the United States. One of these is the Albany, NY HTS Cable Project, involving the installation and operation of a 350 meter HTS cable system with a capacity of 34.5 kV, 800 A, installed between two substations in National Grid's electric utility system. A 320 meter and a 30 meter cable are installed in an underground conduit and connected together by a joint, or splice in a vault. In Phase I of this project, the cables were fabricated with DI-BSCCO wire in a 3-core-in-one cryostat structure. After the installation of the HTS cable system, the in.grid operation began on July 20, 2006 and operated successfully in unattended condition through May 1, 2007. In Phase II, the 30 meter section was replaced by a 2G (YBCO) cable. The 2G cable was fabricated with SuperPower's YBCO coated conductors in a 3 core-in-one cryostat. After replacement of the 30 meter section, the joint and one termination were reassembled and the commissioning tests that included initial cooling, critical current measurement and DC withstand voltage test were completed successfully. After the commissioning tests, the HTS cable system with a 30 meter YBCO cable and a 320 meter DI-BSCCO cable was re-energized on January 8, 2008 and started again to operate in a live utility network. This paper describes the latest status of the Albany HTS cable project. [ABSTRACT FROM AUTHOR]

The US Department of Homeland Security is currently funding the design, development and demonstration of an inherently fault current limiting HTS cable, called Secure Super Grids, under the Hydra project with Con Edison. The cable is 300 m long and is being designed to carry 96 MVA at a distribution level voltage of 13.8 kV. The cable will be built using cable system experience gained by AMSC and Ultera (a Southwire and nkt Cables joint venture) on previous projects. The underground cable will be permanently installed and energized in New York City in 2010. The project is led by American Superconductor who is teamed with Ultera and Con Edison. This paper describes the general goals and design criteria of the project. An overview of the concept of Secure Super Grids and advantages of this type of cable are presented in a grid-based network modeling. In addition, the design issues such as tailoring of the HTS wire to provide adequate thermal stability and electrical properties both under normal operation and during a fault are presented. [ABSTRACT FROM AUTHOR]

The first long length, transmission level voltage, cold dielectric, high temperature superconductor power cable has been successfully installed in the Long Island Power Authority (LIPA) grid. The cable is capable of carrying 574 MVA at a voltage of 138 Ky. Three 600 m long phase conductors were manufactured and shipped to the LIPA site. The installation process included pulling three cables through three separate 600 m long underground conduits and assembly of three terminations at each end. The project has been funded by the US Department of Energy and is led by American Superconductor. The project team is comprised of Nexans, Air Liquide and LIPA. This paper describes the cable system, installation process and an overview of various testing results before and after installation. In addition, details of an initial successful cool-down process are presented. It also includes the performance results in grid operation. [ABSTRACT FROM AUTHOR]

This paper proposes a practical and effective model for the generation forecasting of a wind farm with an emphasis on its scheduling and trading in a wholesale electricity market. A novel forecasting model is developed based on indepth investigations of meteorological information. This model adopts a two-stage hybrid network with Bayesian clustering by dynamics and support vector regression. The proposed structure is robust with different input data types and can deal with the nonstationarity of wind speed and generation series well. Once the network is trained, we can straightforward predict the 48-h ahead wind power generation. To demonstrate the effectiveness, the model is applied and tested on a 74-MW wind farm located in the southwest Oklahoma of the United States. [ABSTRACT FROM AUTHOR]

This paper generalizes Benders decomposition to maximize a nonconcave objective function and uses that decomposition to solve an "electric power grid interdiction problem." Under one empirically verified assumption, the solution to this bilevel optimization problem identifies a set of components, limited by cardinality or "interdiction resource," whose destruction maximizes economic losses to customers (and can thereby guide defensive measures). The decomposition subproblem typically incorporates a set of dc optimal power-flow models that cover various states of repair after an attack, along with a load-duration curve. Test problems describe a regional power grid in the United States with approximately 5000 buses, 6000 lines, and 500 generators. Solution time on a 2-GHz personal computer is approximately one hour. [ABSTRACT FROM AUTHOR]

This paper presents the results of an analysis of indicators that can be used to predict whether a student will succeed in a Computer Science Ph.D. program. The analysis was conducted by studying the records of 75 students who have been in the Computer Science Ph.D. program of the University of Alabama in Huntsville. Seventy-seven variables were extracted from each student's record, and the variables were correlated with whether the student did or did not successfully graduate from the program. A multivariate model was developed that predicts success with a high degree of accuracy. Importantly, the model relies on variables that can be determined reasonably early in a student's Ph.D. class work, enabling its use as a selection metric. Hypotheses about the composition of the model are also presented and discussed. [ABSTRACT FROM AUTHOR]

Under a Navy SBIR, Diversified Technologies, Inc. (DTI) will design and demonstrate scalable solid state switches in support of future U.S. Navy needs related to power supplies and inverters. One switch approach being developed consists of a massive series-parallel array of high-voltage insulated gate bipolar transistors that are switched synchronously in order to achieve high peak currents. DTI is evolving its technology in high-voltage switching to include very high peak currents. As an objective of the SBIR effort, DTI will utilize these high-power switches to build a power converter. From a practical viewpoint, high-voltage switches that can operate reliably at large currents have potential applications in missile launchers, high-power actuators, and radar power supplies. The massive series-parallel switch array approach has the potential to provide a compact, reliable, and effective switching solution to converting sufficient electrical energy to kinetic energy that could meet a variety of Navy applications. In this paper, DTI reviews current switch requirements and recent SBIR progress toward the goal of demonstrating massive series-parallel high-voltage switching that meets the Navy SBIR requirements. [ABSTRACT FROM AUTHOR]

Abstract-Partial discharges (PDs) generate wideband radio-frequency interference which can be used for noninvasive monitoring of discharges. This paper presents a novel method based on this principle for PD monitoring of substations. The significant advantage of this method lies in the ability to detect PD sources in energized equipment anywhere within a substation compound during normal operating conditions. The results obtained from the prototypes installed in the U.K. and U.S. substations are reported. Results include correlation with apparent charge and daily recordings obtained before, during, and after the failure of a 132-kV current transformer and 69-ky voltage transformer. [ABSTRACT FROM AUTHOR]

This paper presents a novel control strategy for series and parallel output dual-buck half-bridge inverters (DBHBIs). With the increasing concern of fossil fuel reserves and the environmental aspects, the 2005 International Future Energy Challenge, sponsored by U.S. the Department of Energy and the Institute of Electrical and Electronics Engineers, required that the grid-connected inverter should provide a single-phase utility line with 110-240 V at either 50/60 Hz. The proposed series and parallel output DBHBI can produce those kinds of voltage by series or parallel connection of two inverters and with digital signal processor (DSP) control to meet the aforementioned specifications. The load current of the two inverters at parallel output association and the load voltage of both at series output association can be shared. The waveform quality of the whole output voltage is high at both associations. Stability and relative stability of the inverter are unaffected at the two output associations. Operating principle, control strategy, stability and relative stability, and design guidelines and examples are illustrated. Experimental results of a 1-kVA DSP-based series and parallel output DBHBI at stand-alone mode verify the theoretical analysis. The comparisons between single and double inverter structures show that the proposed inverter is very promising in applications. [ABSTRACT FROM AUTHOR]

This paper presents a new method for NOAA's (National Ocean and Atmospheric Administration) orbital drift correction. This method is pixel-based, and in opposition with most methods previously developed, does not need explicit knowledge of land cover. This method is applied to AVHRR (Advanced Very High Resolution Radiometer) channel information, and relies only on the additional knowledge of solar zenithal angle (SZA) and acquisition date information. In a first step, anomalies in SZA and channel time series are retrieved, and screened out for anomalous values. Then, the part of the parameter anomaly which is explained by SZA anomaly is removed from the data, to estimate new parameter anomalies, and this iteratively until the influence of SZA anomalies is totally removed from the parameter data. This correction has been applied to bimonthly AVHRR data provided by the GIMMS group (Global Inventory Modeling and Mapping Studies), covering Africa from November 2000 to December 2006. NDVI and LST (Land Surface Temperature) have been estimated from raw and corrected data, and averaged over homogeneous vegetation classes. Differences between raw and corrected averaged parameters show an improvement in the quality of the data. In order to validate this method, a whole week (10 to 17 July 2004) of METEOSAT SEVIRI (Spinning Enhanced Visible and InfraRed Imager) data have been used, from which LST have been estimated using a similar method to the one used to retrieve LST from AVHRR data. The comparison between both platforms at the same time of acquisition shows good concordance. [ABSTRACT FROM AUTHOR]

Global Positioning System (GPS) radio occultation (RO) sounding, with its high vertical resolution temperature and humidity profiling capability, is revolutionizing atmospheric science, particularly through assimilation in numerical weather prediction (NWP) models. Currently, the observations are derived from GPS receivers onboard low Earth orbiting satellites. However, with the current number of satellites, it is difficult to provide dense sounding measurements in a specific region within a limited time period. With a GPS receiver onboard an airplane, the GPS RO technique offers such an opportunity while retaining the high vertical resolution sounding capability. The GNSS Instrument System for Multistatic and Occultation Sensing is currently under development for the National Science Foundation's High-performance Instrumented Airborne Platform for Environmental Research (HIAPER) aircraft. This paper presents a sensitivity analysis of the airborne occultation technique that will be used for the HIAPER system. The results demonstrate an anticipated overall accuracy of better than 0.5% for the retrieved refractivity from the surface to about 1 km below the airplane, where the expected airplane velocity errors of up to 5 mm/s limit the accuracy. The effects on the retrievals due to horizontal variations in atmospheric refractivity are significant, and retrieval errors may reach several percent inside frontal systems when the front is perpendicular to the ray paths and within 200 km of the tangent point. In general, the airborne GPS RO system provides a promising new data source for NWP and targeted observational studies. [ABSTRACT FROM AUTHOR]

Tests of up to three simultaneously firing 40-cm NASA's Evolutionary Xenon Thrusters took place at NASA Glenn Research Center. In addition to numerous engineering tests, the experiment was instrumented to measure plasma properties in the interacting plumes, charge exchange return current to the active and dormant thrusters, and current and plasma properties at various locations. This paper describes the use of Nascap-2k to calculate plume potentials and charge exchange ion return currents to active and dormant ion optics and to diagnostic probes. Calculations were performed varying the numbers of active thrusters, thruster power levels, and gimbaling. The results were extrapolated to space conditions. Despite several simplifying assumptions, we obtained good agreement with experimental results. No major problems associated with multiple thruster operation were found. [ABSTRACT FROM AUTHOR]

Jet Propulsion Laboratory (JPL) is currently assessing the applicability of the 25-cm Xenon Ion Propulsion System (XIPS) as part of an effort to infuse low-cost technically mature commercial ion thruster systems into NASA deep space missions. Since these mission require extremely long thruster lifetimes to attain the required mission ΔV, this paper is focused on understanding the dominate wear mechanisms that effect the life of the XIPS three-grid system. Analysis of the XIPS three-grid configuration with JPL's CEX3D grid erosion model shows that the third "decel" grid effectively protects the accel grid from pits and grooves erosion that is commonly seen with two-grid ion thruster grid systems. For a three-grid system, many of the charge-exchange ions created downstream of the grid plane will impact the decel grid at relatively low energies (~25 V), instead of impacting the accel grid at high energies (~200 V), thus reducing overall erosion. JPL's CEX3D accurately predicts the erosion patterns for the accel grid, although it appears to overpredict the pits and grooves erosion rates due, mainly, to uncertainties in incident energies and angles for sputtering ions and since it does not account for local redeposition of sputtered material. Since the model accurately simulates the erosion pattern but tends to overpredict the erosion rates for both the two- and three-grid sets, this comparative analysis clearly shows how the decel grid significantly suppresses the erosion of the downstream surface of the accel grid as observed in experimental tests. The results also show that the decel grid has a relatively small effect on barrel erosion (erosion of the aperture wall) and erosion of the upstream surface of the accel grid. Decreasing the accel grid voltage of the XIPS can reduce barrel (and total) erosion of the accel grid and should be considered for high-ΔV missions. [ABSTRACT FROM AUTHOR]

With the current trend in deregulation, all electricity markets have been subject to volatile electricity prices, typically in peak season. As markets mature, new financial and operational risk management instruments are becoming available. In order to price such instruments, a model for the underlying price process is required. In this paper a hybrid model is described that contains aspects of the power system, as well as the historical time-series of spot prices observed in the market. By including both aspects of the problem, a model with both economic and system-based aspects is created. Its modular design allows easy adaptation to different markets based on generating system reliability, load patterns, and price histories. The spot price histories are manifest in two probability distributions for these prices, whereas the system specifics are included via load and generation models which are calibrated to the climate and system of interest. This model is tested and validated using the Pennsylvania-Jersey-Maryland Market, and is effective is reproducing out-of-sample market behavior. In addition, we conduct an investigation of the sensitivity of the model to various underlying assumptions, such as the shape of the repair time distribution. Preliminary testing of the model on the Alberta Power Market briefly described here were also successful. These investigations provide important insights into some of the driving factors for electricity price spikes. [ABSTRACT FROM AUTHOR]

The U.S. legislation at both the federal and state levels mandates certain organizations to inform customers about information uses and disclosures. Such disclosures are typically accomplished through privacy policies, both online and offline. Unfortunately, the policies are not easy to comprehend, and, as a result, online consumers frequently do not read the policies provided at healthcare Web sites. Because these policies are often required by law, they should be clear so that consumers are likely to read them and to ensure that consumers can comprehend these policies. This, in turn, may increase consumer trust and encourage consumers to feel more comfortable when interacting with online organizations. In this paper, we present results of an empirical study, involving 993 Internet users, which compared various ways to present privacy policy information to online consumers. Our findings suggest that users perceive typical, paragraph-form policies to be more secure than other forms of policy representation, yet user comprehension of such paragraph-form policies is poor as compared to other policy representations. The results of this study can help managers create more trustworthy policies, aid compliance officers in detecting deceptive organizations, and serve legislative bodies by providing tangible evidence as to the ineffectiveness of current privacy policies. [ABSTRACT FROM AUTHOR]

Given their complexity and tight coupling, one of the most serious challenges high-reliability organizations (HROs) face is how to innovate, learn, and adapt without upsetting the internal processes that lead to their reliability. This paper describes the success of the United States Navy in using a "platform strategy" to facilitate modular innovation in its attack submarine program while maintaining high reliability. We compare the United States' submarine development program against that of the Soviets, who innovated by building a number of different types of nuclear attack submarines to test their new design concepts and thereby aggressively push both manufacturing and performance limits. We illustrate that, by adopting a platform strategy, the U.S. development program was able to sustain reliability by controlling factors that derived from four classes of concern: 1) operational; 2) manufacturing and design; 3) resource limitations, and 4) cultural constraints. The use of a platform strategy assists in maximizing systemwide organizational learning, which helps enrich a culture of reliability. However, at the same time, a platform strategy can hinder revolutionary and architectural innovation and reduce op- erational flexibility. Finally, we consider whether an HRO's innovation strategy is partially shaped by its decision-making process. [ABSTRACT FROM AUTHOR]

This paper examines strategic capabilities as drivers of the development and launch of radical innovations. We construct a theoretical framework relating five strategic capabilities (mar- keting, market linking, technology, information technology, and management-related capabilities) to radical innovation. From this framework, we derive hypotheses concerning a division's propensity to engage in radical innovation. Using empirical data derived from a research study of 376 firms in the United States, Japan, and China, we apply analysis of variance and negative binomial distribution (NBD) regression techniques to test our hypotheses. We find evidence that, overall, technology and information technology capabilities are significantly and positively related to radical product innovation. We also find some significant differences among the three country samples concerning drivers of radical innovation. Marketing capability is more significantly and positively related to radical innovation in the United States than in Japan; and, in China, the only capability that is significantly and positively related to radical innovation is technology. All of the findings completely or partially support our research hypotheses. We conclude with a discussion of the managerial implications of our findings, and directions for future research. [ABSTRACT FROM AUTHOR]

The US National High Magnetic Field Laboratory constructed and tested a stand-alone 80 T prototype magnet. The activity was in support of the insert magnet development project for the US-DOE-NSF 100 Tesla Multi-Pulse Magnet Program. The 80 T magnet assembly was developed to simulate the physical conditions an insert magnet would encounter during peak field operations at 105 T… The design incorporated further improvements to the engineering template developed from the 65 T and 75 T pulsed magnets now in use at the NHMFL Pulsed Field Facility at Los Alamos National Laboratory. Two coaxially nested solenoid coils comprised the 80 T prototype magnet design. The windings are in series electrically. The inner coil is constructed with materials & techniques identical to those in use for the 100 T insert program. The outer coil is a conventional winding. The prototype was successfully trained to a peak field of ~80.4 T. 80 T pulsed operations were repeated until the coil assembly faulted after 10 full-field pulses. Post-fault inspection of the magnet assembly indicated that the outer magnet winding failed structurally. This paper will present an overview of the 80 T prototype's design, construction, and performance. A review of the magnets failure mode will be presented. Additionally, we will discuss new design criteria for stand alone high-field pulsed magnet based upon the 80 T prototype experience. [ABSTRACT FROM AUTHOR]

The U. S. National High Magnetic Field Laboratory 100 Tesla Multi-Pulse Magnet System is now successfully commissioned. This magnet system is the result of a long-term partnership project jointly funded by the U. S. Department of Energy-Office of Basic Energy Science and the National Science Foundation. Science experimentation inside the magnet started in December 2006 at the NHMFL Pulsed Field Science Facility located at Los Alamos National Laboratory. Repeated, non-destructive operation of the system with original components is continuing in the 85 T to 90 T range. The system will eventually combine, a nominal 40 T platform field produced by a controlled-waveform generator-powered long-pulse magnet with a nominal 60 T field generated by a capacitor-bank powered pulsed insert magnet to produce the rated field. Milestone non-destructive operation to 88.9 T was achieved in October 2006. This paper will present an overview of the generator driven outsert magnet system together with the high-field pulsed insert magnet's design and construction. We will review commissioning and performance data through summer of 2007. Criteria for increasing the systems maximum field performance will also be reviewed addressing the goal to increase operating field level (in support of experiments) to 95 T and then to 100 T. [ABSTRACT FROM AUTHOR]

The National High Magnetic Field Laboratory (NHMFL) has embarked on an innovative program to develop a number of Series-Connected-Hybrid magnetic systems. In this novel concept, a set of resistive coils (insert) and a set of superconducting cable-in-conduit conductor (CICC) coils (outsert) are electrically driven in series, rather than independently as in previous hybrid systems. Presently NHMFL is working on 3 different projects. The first, funded by the National Science Foundation (NSF) with an $11.7 million grant, is related to the construction of a cylindricel-bore Series-Connected Hybrid (SCH), for high field nuclear magnetic resonance (NMR), condensed matter physics, biology and chemistry, to be located at the Magnet Lab's Tallahassee location. The second, funded by the Hahn-Meitner Institute (HMI) in Berlin, relates to the engineering design for a horizontal bore Series-Connected Hybrid to be used in a neutron diffraction experimental system. Finally, the third, also funded by NSF, is a conceptual and engineering study for an SCH that would be used for neutron scattering experiments at Oak Ridge National Laboratory's Spallation Neutron Source (SNS), similar to the HMI version. Because of the main points in common between the 3 different systems, our final goal is to develop a superconducting magnetic system suitable for the 3 applications. We believe this is possible for the magnet although, due to the different field/bore orientations, some differences in the mechanical design of the cryostat and resistive inserts will exist. In this paper we will give an overview of the R&D strategy devised to develop these superconducting magnetic systems, together with a report on the present status of such program. [ABSTRACT FROM AUTHOR]

Ancillary service markets are a very important part of the Standard Market Design and are under development or implementation on a centralized basis in major U.S. electricity markets. This paper presents the market clearing framework for the co-optimized real-time energy-reserve market that has been developed and implemented in the ISO New England (ISO NE). In this co-optimized market clearing model, reserve, products are procured on a zonal basis to satisfy the first and the second contingency protection criteria required by the ISO NE's real-time operations for both the entire area and typical import-constrained areas. The proposed zonal reserve model is derived from simulating each contingency event in the predefined reserve zones. Differing from standard industrial practices, the proposed zonal reserve model recognizes reserve deliverability for nested reserve zones and allocates the zonal total transfer capability between energy and reserves in an economic way. Numerical examples for a two-zone system are presented to demonstrate the validity of this modeling technique. [ABSTRACT FROM AUTHOR]

Combining data sets from multiple satellite sensors is a powerful method for studying Earth-atmosphere problems. By fusing data, we can utilize the strengths of the individual sensors that may not be otherwise possible. In this paper, we provide the framework for combining level 2 data products, using data from three sensors aboard the National Aeronautics and Space Administration (NASA)'s Terra satellite. These data include top-of-the-atmosphere (TOA) radiative energy fluxes obtained from the Clouds and the Earth's Radiant Energy System (CERES), aerosol optical thickness from the multispectral Moderate Resolution Imaging Spectroradiometer (MODIS), and aerosol properties from the Multi-angle Imaging SpectroRadiometer (MISR). The CERES Single Scanner Footprint (SSF) contains the pixel level CERES TOA fluxes and the level 2 MODIS aerosol data. We specifically focus upon fusing the CERES SSF with the MISR aerosol products. Although this project was undertaken specifically to address aerosol research, the methods employed for fusing data products can be used for other problems requiring synergistic data sets. We present selected case studies over different aerosol regimes and indicate that multisensor information provides value-added information for aerosol research that is not available from a single sensor. [ABSTRACT FROM AUTHOR]

Ground-based augmentation systems (GBAS), such as the Federal Aviation Administration's Local Area Augmentation System (LAAS), protect GPS users against signal anomalies by monitoring for rare satellite faults. This paper introduces a new, time-varying MERR (maximum-allowable error in range) formulation that enables proof of integrity for ground-based fault monitoring. The time-varying MERR supersedes earlier MERR methods which relied on a static integrity test. The utility of these earlier methods was limited in that they neglected GBAS time-to.alert (TTA) requirements and restricted the choice of the monitor filter, requiring its impulse response to match that of the user ranging-error filter. By contrast, the time-varying MERR explicitly incorporates TTA and places no restrictions on monitor filter design. These attributes are critical for correctly evaluating system integrity and for crediting the integrity benefits of GBAS systems with aggressive filter designs and process timing. [ABSTRACT FROM AUTHOR]

This paper demonstrates the results from a detailed study of the overvoltage protection of a particular 400/150-kV 400-MVA power transformer. The work presented here is based on a real-life power system substation design and data and initiated by Danish TSO Energinet.dk as a consequence of serious transformer overvoltag damage. A simulation model for the entire system consisting of overhead line, transformer, surge arrester, and earth grid has been created in PSCADIEMTDC. The main focus has been put on the earth grid, which has been submodeled in detail in MATLAB using an electromagnetic transient approach based on the thin-wire program made by J. H. Richmond for NASA in 1974. The earth grid model is verified with excellent agreement compared to already published results. The overvoltage performance of the particular case is analyzed, and it shows that the transformers LIWL have probably been exceeded. It is clearly illustrated that the transient performance of the earth grid plays an important role in the overall overvoltage protection system design. [ABSTRACT FROM AUTHOR]

Terrestrial Television Broadcasting has always been an interference limited service. In 2009, the FCC plans to end analog TV transmissions by full power TV stations in the USA and to reduce the broadcast TV spectrum and to allow sharing of the remaining TV broadcast spectrum by unlicensed devices. DTV signals will use first adjacent channels in the same community and there will be no UHF Taboos to protect against interference which results from receiver non-linearity, especially that due to multiple signals ~n certain channels which results in 3'~' order intermodulation 9roducts which fall in the channel to which the receiver is tuned. This paper will explain the problems caused and ~uggest means to improve receiver performance' [ABSTRACT FROM AUTHOR]

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

This paper investigates anomalous inversion capacitance-voltage (C-V) attenuation for MOSFETs with leaky dielectrics. We propose to reconstruct the inversion C-V characteristic based on long-channel MOSFETs using the concept of intrinsic input resistance (Rii). The concept of Rii, has been validated by segmented BSIM4/SPICE simulation. Our reconstructed C-V characteristics show poly-depletion effects, which are not visible in the two-frequency three-element method and agree well with the North Carolina State University-CVC simulation results. The intrinsic input resistance dominates the overall gate-current-induced debiasing effect (~95% for L = 20 µm) and can be extracted directly from the I-V characteristics. Due to its simplicity, our proposed Rii, approach may provide an option for regular process monitoring purposes. [ABSTRACT FROM AUTHOR]

This paper develops an empirical confidence bound for barometric altimeter altitude errors and shows how this bound may improve the performance of GPS-based approach and landing systems. This empirical bound is developed using historical meteorological data collected at a set of geographically diverse locations over a thirty year period. The confidence bound developed is shown to provide a Gaussian overbound on altimeter altitude errors in standard atmospheric conditions between a 10-5 and 10-6 confidence level. This confidence bound is integrated into the standard methodology for analyzing the performance of GPS-based landing systems and the results of a performance trade study using the confidence bound are presented. The results show that incorporating the empirical barometric altimeter confidence bound provides an increase in the coterminous United States (CONUS) service volume for lateral precision with vertical guidance (LPV) type approaches. While this increase is approximately 2% for an L1 single-frequency GPS user, it jumps to roughly 40% for an L5 single-frequency user. [ABSTRACT FROM AUTHOR]

This paper presents the development of a micro-machined dual-backplate capacitive microphone for aeroacoustic measurements. The device theory, fabrication, and characterization are discussed. The microphone is fabricated using the five-layer planarized-polysilicon SUMMiT V process at Sandia National Laboratories. The microphone consists of a 0.46-mm-diameter 2.25-μm-thick circular diaphragm and two circular backplates. The diaphragm is separated from each backplate by a 2-μm air gap. Experimental characterization of the micro-phone shows a sensitivity of 390 μV/Pa. The dynamic range of the microphone interfaced with a charge amplifier extends from the noise floor of 41 dB/√Hz up to 164 dB and the resonant frequency is 178 kHz. [ABSTRACT FROM AUTHOR]

This paper presents the development of a single-phase utility-interactive inverter for residential power generation to meet the specifications laid down for the 2005 Future Energy Challenge Competition sponsored by U.S. DOE and IEEE. The proposed inverter system is capable of working in both stand-alone and grid-connected mode. A control scheme for implementing both modes of operation is presented, which has simple structure with smaller number of sensors. The proposed control algorithm including the whole system control is implemented on a low cost, fixed-point DSP TM5320F2812. The experimental results from a I kW prototype show that the proposed inverter system exhibits not only low THD grid current during the grid-connected mode and well regulated inverter voltage during the stand-alone mode, but also smooth and automatic transfer between the two modes of operation. [ABSTRACT FROM AUTHOR]

This paper presents the validation of a numerical model based on the full-scale broken insulator tests on a 138-kV high-voltage steel transmission line. The University of Wisconsin and the Electric Power Research Institute performed these tests in 1978. A finite-element model of the line is developed to perform incremental nonlinear dynamic analysis, carried out in the time domain. Upon validation of the numerical model with the test results, a sensitivity study is carried out for various insulator lengths, ice thicknesses, and initial tensions to determine the effects of these parameters on the impact loads on the tower cross arm. Results of the study show that the impact loads are less sensitive to the change in insulator length but they do vary significantly when the ice loads and the initial tensions are increased. Studies of this type are now possible and are cost effective because of the use of commercial software not available at the time of the original research. [ABSTRACT FROM AUTHOR]

The generalization error bounds found by current error models using the number of effective parameters of a classifier and the number of training samples are usually very loose. These bounds are intended for the entire input space. However, support vector machine (SVM), radial basis function neural network (RBFNN), and multilayer perceptron neural network (MLPNN) are local learning machines for solving problems and treat unseen samples near the training samples to be more important. In this paper, we propose a localized generalization error model which bounds from above the generalization error within a neighborhood of the training samples using stochastic sensitivity measure. It is then used to develop an architecture selection technique for a classifier with maximal coverage of unseen samples by specifying a generalization error threshold. Experiments using 17 University of California at Irvine (UCI) data sets show that, in comparison with cross validation (CV), sequential learning, and two other ad hoc methods, our technique consistently yields the best testing classification accuracy with fewer hidden neurons and less training time. [ABSTRACT FROM AUTHOR]

Measurements of water vapor and clouds in the polar regions are difficult, because conventional instruments show little sensitivity (∼1.3 K/mm) to low amounts. On the other hand, millimeter- and submillimeter-wavelength radiometry offers greatly enhanced sensitivity (up to 51.4 K/mm, depending upon frequency). For this reason, the National Oceanic and Atmospheric Administration's Physical Science Division designed a new instrument, the Ground-Based Scanning Radiometer (GSR), for continuous and unattended observations at millimeter and submillimeter wavelengths (50-380 GHz). The GSR was deployed for the first time during the Arctic winter radiometric experiment in March-April 2004. In this paper, we discuss the GSR calibration procedure, which allows for accurate measurements during clear and cloudy skies. Error-budget analysis and comparison with independent measurements show an absolute accuracy on the order of 1-2 K. Examples of multifrequency and multiangle GSR observations are illustrated, representing a valuable new data set for the study of water vapor, clouds, and atmospheric absorption models in the Arctic. [ABSTRACT FROM AUTHOR]

The evaluation of locational marginal prices or LMPs, which constitute the basis of the new generation of market design in the U.S., is a critical need in the side-by-side operation of electricity markets and power systems. Their use in various applications such as congestion management and hedging requires specific LMP components in the computations. We provide a general formulation for the evaluation of the LMP components by making explicit use of the important role played by the nodes with generators with free capacity. On the other hand, the LMPs of the nodes without generation or with the generators at their limits are a function of the LMPs at the marginal nodes and the impacts of the network constraints, including the losses in the network. In the formulation, we pay special attention to the importance of the assumptions and specifications—the so-called policy specification—in the determination of the components. We obtain a very general formulation that brings under a single framework the different decomposition approaches that exist. The formulation's comprehensiveness brings numerous insights into the various decompositions, provides a platform for their comparative analysis, and allows us to understand the direct implications and the role of the policy specified. Moreover, the formulation reveals the limitations of any decomposition into the components due to the underlying structural interdependencies among them, which is clearly shown in this paper. We provide an example to illustrate the capabilities and the insights obtainable with the use of this formulation. [ABSTRACT FROM AUTHOR]

On August 14, 2003, the U.S. faced the largest blackout in history, which left over 50 million people without electricity in eight U.S. states and part of Canada. This paper investigates the effects of the blackout on the security values of the U.S. electric utilities and manufacturing firms in the electric power equipment industry, using an event study method. The results of this empirical study show that the electric utilities were negatively affected, but the electrical equipment manufacturing firms were significantly, positively affected. [ABSTRACT FROM AUTHOR]

Foreign-born scientists and researchers have long been a fixture in the U.S. R&D system. This paper examines a key indicator of scientific performance—individual research productivity. In a large sample of public sector researchers in nanoscience and technology, it was found that foreign-born scientists are consistently more productive than their native-born counterparts across different organizational settings and within a federal laboratory environment. The results furthermore show that male foreign-born researchers are more productive than their female peers in an unusually multidisciplinary research environment, except in the federal laboratory system. Both policy and management implications of these findings will be discussed. An open-versus closed-door immigration policy debate has historically resulted in policies that favor an open-door immigration policy for foreign-born researchers, but lately, and particularly since September 2001, the policy pendulum has started to swing in the other direction. I argue that a reasonable and sound immigration and science policy would balance the benefits of having a strong contingent of foreign-born researchers with the interests of current and future native-born researchers. Research-intensive organizations would serve their interests well by initiating or sustaining diversity and equal opportunity employment practices, which are likely to have a positive impact on research productivity. [ABSTRACT FROM AUTHOR]

In support of the development of a large-aperture Nb3Sn superconducting quadrupole for the Large Hadron Collider luminosity upgrade, two models (TQS and TQC) with a 90-mm aperture are being constructed at LBNL and FNAL within the framework of the US LHC Accelerator Research Program (LARP). These models use two identical Nb3Sn coils but have different coil support structures. This paper describes the fabrication, assembly, cool-down and test of TQS01—a model based on key and bladder technology with supporting iron yoke and an aluminum shell. Comparison of the test measurements with design expectations is also reported. [ABSTRACT FROM AUTHOR]

Dynamic texture (DT) is an extension of texture to the temporal domain. Description and recognition of DT5 have attracted growing attention. In this paper, a novel approach for recognizing DTs is proposed and its simplifications and extensions to facial image analysis are also considered. First, the textures are modeled with volume local binary patterns (VLBP), which are an extension of the LBP operator widely used in ordinary texture analysis, combining motion and appearance. To make the approach computationally simple and easy to extend, only the co-occurrences of the local binary patterns on three orthogonal planes (LBP-TOP) are then considered. A block-based method is also proposed to deal with specific dynamic events such as facial expressions in which local information and its spatial locations should also be taken into account. In experiments with two DT databases, DynTex and Massachusetts Institute of Technology (MIT), both the VLBP and LBP-TOP clearly outperformed the earlier approaches. The proposed block-based method was evaluated with the Cohn-Kanade facial expression database with excellent results. The advantages of our approach include local processing, robustness to monotonic gray-scale changes, and simple computation. [ABSTRACT FROM AUTHOR]

Mapping shallow-water bathymetry with acoustic techniques is complicated and expensive. The environmental parameters in shallow-water (< 2 m) areas become more variable and greatly impact the depth extraction from the survey measurements. Current airborne light detection and ranging (LIDAR) bathymetry surveying in shallow-water depths uses green-channel waveforms to measure the water depth. Unfortunately, due to difficulties in distinguishing between the surface and bottom return of the water column, the timing of the bottom return is often ambiguous. Furthermore, the water often becomes optically ‘dirty’ due to turbulence at these shallow depths. Therefore, it is common to find coastal areas that lack any measured depths. This paper presents a novel approach for measuring water depths in these shallow coastal waters with airborne LIDAR. Observations of the red-channel waveforms show that the waveforms are divided into two groups, namely: 1) waveforms in deep waters (> 2 m) whose shape is invariant with respect to the water depth and 2) waveforms in shallow-water depths that show a change in shape as a function of the depth in the water column. The data for this study are from the US Geological Survey LIDAR surveys of Lake Tahoe, CA, and Lake Michigan, using a SHOALS-400 LIDAR system. [ABSTRACT FROM AUTHOR]

Natural gas fired power plants (NGFPP) are important electricity generation resources in the United States. Optimizing the natural gas supply portfolio, especially the short-term portfolio, is critical for the day-to-day operations and the financial performance of NGFPPs. Traditionally, such optimization problems are solved using cost-minimization-based frameworks. However, such frameworks are facing challenges due to the lack of consideration of associated financial risks in the current deregulated electricity markets, which the electric utility companies (EUCs) who own and operate NGFPPs now bear. This paper presents a utility-maximization-based framework to optimize the short-term natural gas supply portfolio for the EUC. It considers the financial risks associated with the portfolio and incorporates the risk preferences of the EUCs as decision-maker (DM) in the portfolio optimization process. An application of the proposed framework is provided, and its results show that the proposed framework is more desirable in terms of risk-cost trade-off optimization. [ABSTRACT FROM AUTHOR]

Companies across industries have admired the success of Dell Computersin using modularity as part of a mass customization strategy to achieve build-to-order and a streamlined supply chain. Many companies are attempting to emulate this successful model, including the American automotive industry. This paper focuses on how the auto industry has been attempting to move to modularity, in part, motivated by a desire to build cars to order. This movement has led to major changes in supply chain practices based partly on imitation of successful keiretsu models in Japan and a move toward modules. This study finds significant impact of modularity on outsourcing, product development, and supply chain coordination based on interviews conducted with automakers and suppliers from 2009-2003. Based on our interviews, we observe that modularity has accompanied a major reorganization of the automotive supplier industry. We identify two major issues that appear to block U.S. automakers from gaining most of the advantages possible through modularity. First, most modularity activities appear to be primarily strategically cost reduction driven, leaving the potential of modularity for mass customization largely untapped. Second, the shift in industry reorganization has not been accompanied by changes in the supply chain infrastructure to encourage long-term partnerships. We contrast this to the more gradual approach used by Toyota as it incorporates modularity on a selective basis and moves to a build-to-order model. [ABSTRACT FROM AUTHOR]

Electromagnetic (EM) launch science and technology in the United States continues to advance at a significant pace. The computational and experimental tools for understanding the critical physics issues are sufficiently mature that they are being utilized to provide insight and resolution of the remaining major technical challenges. For example, the primary computational electrodynamics code, EMAP3D, is now implemented in a hybrid finite element-boundary element configuration with moving conductors, providing faster computation and increased understanding of these complex systems. An increased focus on railgun tribology and experiments to understand the interface between railgun armatures and the rail surface is providing important insight for improved railgun lifetimes. Control algorithms for counter-rotating pulsed alternators have been developed and validated experimentally with physical scale simulators. Solid-state switches are replacing the more traditional vacuum switches for high-current and high-voltage railgun power sources. Silicon is the material of choice, but silicon carbide shows great promise for reduced size and increased electrical performance. As a consequence of these and other advances, the U.S. Army has initiated an effort to build a power source with a matched pair of counter-rotating pulsed alternators and a cantilevered railgun to accelerate projectiles to 2-MJ kinetic energy. The U.S. Navy has initiated a new effort to launch large projectiles to hypervelocity. Because of the large naval platform, the size and weight of the power source are not significant issues for the U.S. Navy, whose primary interest is in providing precision fire support to ranges in excess of 200 nmi (500 km). The critical technical issues in implementing this application for the Navy are railgun bore lifetime and high-acceleration-tolerant guidance and control. This paper highlights the recent major achievements in hypervelocity physics, pulsed power, and railgun lifetimes that provide the critical science and technology underpinnings for the Army and Navy EM gun programs. [ABSTRACT FROM AUTHOR]

With the transition to digital terrestrial television (DTV) in the U.S. scheduled to be complete by 2009, the Federal Communications Commission (FCC) has issued a notice of proposed rule making (NPRM) that, if adopted, would allow transmission by unlicensed devices on frequencies of vacated television channels. The FCC is required by statute to avoid harmful interference to licensed TV channels. This paper addresses two of the core questions related to the proposed introduction of unlicensed transmissions in the vacated TV channels: Do the proposed rules provide DTV stations adequate protection from interference from these devices? If not, what rules must be adopted to avoid harmful interference to terrestrial DTV service from these devices? [ABSTRACT FROM AUTHOR]

In a competitive electricity market, a generation company (Genco) can manage its trading risk through trading electricity among multiple markets such as spot markets and contract markets. The question is how to decide the trading proportion of each market in order to maximize the Genco's profit and minimize the associated risk. Based on the mean-variance portfolio theory, this paper proposes a sequential optimization approach to electric energy allocation between spot and contract markets, taking into consideration the risks of electricity price, congestion charge, and fuel price. Especially, the impact of the fuel market on electric energy allocation is analyzed and simulated with historical data in respect of the electricity market and other fuel markets in the U.S. Simulation results confirm that the proposed analytic approach is consistent with intuition and therefore reasonable and feasible for a Genco to make a trading plan involving risks in an electricity market. [ABSTRACT FROM AUTHOR]

Tests of arcing and current collection in simulated-space-plasma conditions have been performed at the National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) in Cleveland, OH, for over 30 years and at the Marshall Space Flight Center (MSFC) in Huntsville, AL, for almost as long. During this period, proper test conditions for an accurate and meaningful space simulation have been worked out, comparisons with actual space performance in spaceflight tests and with real operational satellites have been made, and NASA has achieved the authors' own internal standards for test protocols. It is the purpose of this paper to communicate the test conditions, test procedures, and types of analysis used at the NASA GRC and MSFC to the space environmental testing community at large, to help with international space-plasma arcing-testing standardization. Discussed herein are the neutral gas conditions, plasma densities and uniformity, vacuum chamber sizes, sample sizes and Debye lengths, biasing samples versus self-generated voltages, floating samples versus grounded samples, test electrical conditions, arc detection, preventing sustained discharges during testing, real samples versus idealized samples, validity of low Earth orbit tests for geosynchronous Earth orbit samples, extracting arc threshold information from an arc rate versus voltage tests, snapover, current collection and glows at the positive sample bias, Kapton pyrolysis, thresholds for trigger arcs, sustained arcs, dielectric breakdown and Paschen discharge, tether arcing and testing in very dense plasmas (i.e., thruster plumes), arc mitigation strategies, charging mitigation strategies, models, and analysis of test results. Finally, the necessity of testing will be emphasized, not to the exclusion of modeling, but as part of a complete strategy for determining when and if arcs will occur, and preventing them from occurring in space. [ABSTRACT FROM AUTHOR]

Electrical safety needs to be refocused. Over the last few years, there has been tremendous attention given to the arc flash hazard phenomenon. Even though this hazard needs attention to reduce the number of injuries occurring because of it, in some ways, it has become the predominate focus of electrical safety. Electrical safety is more than just the arc flash hazard. Electrical safety needs to be a holistic approach that includes all aspects of electrical safety. The Electrical Safety Program, which proved to be a good tool, is defined in NFPA 70E, Standard for Electrical Safety Requirements for Employee Workplaces. However, even this falls short of what is needed to make a step change in electrical safety performance. This paper will attempt to identify the voids in electrical safety and focus attention on the items that need to be addressed to take a more holistic approach to electrical safety. [ABSTRACT FROM AUTHOR]

Increasing the capacity of the very high frequency air/ground (A/G) radio system that supports United States air traffic control is a major reason for upgrading the system to a four-slot time-division multiple-access (TDMA) architecture. Since aviation safety requires a dedicated, immediately accessible AJG circuit for each controller, the thousands of circuits in the nationwide system must have compatible frequency/slot assignments that will allow them all to operate simultaneously if necessary. System capacity may be defined as the size to which the system can grow before it will no longer be feasible to find a compatible assignment for every required new circuit. This paper describes a strategy for combining MG circuits into multislot TDMA ‘bundles’ in a way that will enhance capacity by efficiently using available frequencies and slots. To quantify the resultant capacity gain, the authors have applied the strategy in a series of nationwide system growth simulations, noting the numbers of hypothetical future circuit requirements that were met before frequency denials started to become necessary in some cases. Their results indicate that the capacity of the TDMA version of the system would be 2.8-3.7 times that of the present-day AM analog version. [ABSTRACT FROM AUTHOR]

The modern power infrastructure has evolved from small isolated circuits into an expansive interconnected system that is dependant on multiple supporting infrastructures. One of the most significant and potentially detrimental supporting infrastructures to interact with power systems is telecommunications. Currently, there are no established analytic techniques that enable system operators or planners to analyze the interactions that occur at the seam between these two infrastructures. This paper presents a method for analyzing and assessing events that occur at the interface of the power and telecommunications infrastructures. [ABSTRACT FROM AUTHOR]