Adaptive mesh refinement is complicated by both the algorithms and the dynamic nature of the computations. In parallel the complexity of getting good performance is dependent upon the architecture and the application. Most attempts to address the complexity of AMR have lead to the development of library solutions, most have developed object-oriented libraries or frameworks. All attempts to date have made numerous and sometimes conflicting assumptions which make the evaluation of performance of AMR across different applications and architectures difficult or impracticable. The evaluation of different approaches can alternatively be accomplished through simulation of the different AMR processes. In this paper we outline our research work to simulate the processing of adaptive mesh refinement grids using a distributed array class library (P++). This paper presents a combined analytic and empirical approach, since details of the algorithms can be readily predicted (separated into specific phases), while the performance associated with the dynamic behavior must be studied empirically. The result, AMRSim, provides a simple way to develop bounds on the expected performance of AMR calculations subject to constraints given by the algorithms, frameworks, and architecture.

Modern antennas especially arrays are being placed in layers of materials on complex environments. This technique produces aesthetically pleasing structures if necessary, allows for more freedom in structure planning, and can improve antenna performance. In the past, buried antennas have been studied by numerous authors such as in Reference. Recent work on this subject uses spectral and/or numerical moment method formulations. For high frequency analysis it is important to find efficient and accurate methods for design purposes. A rigorous recursive method for plane waves reflection and transmission coefficients by Richmond has been used in the past for dipoles above multilayer slabs. This solution is modified in this paper to account for forward and backward traveling rays with appropriate spread factors for a dipole in the media. Extensive validation for this approximate method shows good agreement with a Method of Moments code. This code is developed at Lawrence Livermore National Laboratory. The geometry for these comparisons uses a dipole in nontruncated dielectric multilayer slabs.

The authors discuss the decay of axion walls bounded by strings and present numerical simulations of the decay process. In these simulations, the decay happens immediately, in a time scale of order the light travel time, and the average energy of the radiated axions is <w{sub a}> {approx_equal} 7m{sub a} for v{sub a}/m{sub a} {approx_equal} 500. <w{sub a}> is found to increase approximately linearly with ln(v{sub a}/m{sub a}). Extrapolation of this behavior yields <w{sub a}> {approx_equal} 60 m{sub a} in axion models of interest.

The COPS test set provides a modest selection of difficult nonlinearly constrained optimization problems from applications in optimal design, fluid dynamics, parameter estimation, and optimal control. In this report we describe version 2.0 of the COPS problems. The formulation and discretization of the original problems have been streamlined and improved. We have also added new problems. The presentation of COPS follows the original report, but the description of the problems has been streamlined. For each problem we discuss the formulation of the problem and the structural data in Table 0.1 on the formulation. The aim of presenting this data is to provide an approximate idea of the size and sparsity of the problem. We also include the results of computational experiments with the LANCELOT, LOQO, MINOS, and SNOPT solvers. These computational experiments differ from the original results in that we have deleted problems that were considered to be too easy. Moreover, in the current version of the computational experiments, each problem is tested with four variations. An important difference between this report and the original report is that the tables that present the computational experiments are generated automatically from the testing script. This is explained in more detail in the …

This report explores key aspects of the intersection between the nation's clean air and energy goals and proposes alternatives for encouraging renewable energy in the context of the federal Clean Air Act (CAA). As with most environmental statutes enacted in the early 1970s, the 1970 CAA embraced a somewhat rigid ''command-and-control'' approach to achieving its clean air goals. Although effective, this approach has been criticized for discouraging creative and cost-effective solutions to reducing air emissions. In response to this concern, Congress included the first significant market-based program to address an environmental problem-in this case, acid rain caused by sulfur dioxide (SO2) emissions from power plants-in the 1990 CAA Amendments. This program prompted the federal government and various state governments to pursue other market-based programs to address air pollution problems. Ten years have elapsed since the passage of the 1990 CAA Amendments, so the time is ripe to consider expanding opportunities for renewable energy development in the reform of clean air policies. A significant potential for renewables exists in conjunction with international efforts to reduce emissions of greenhouse gases (GHG), including CO2. Unfortunately, Congressional opposition to international GHG reduction agreements makes it difficult to develop GHG emission-reduction programs, including a cap-and-trade …

Correspondence issued by the General Accounting Office with an abstract that begins "This report discusses the use of intellectual property generated at the Department of Energy's (DOE) laboratories to satisfy defense contractors' offset requirements. GAO found that DOE's laboratory offset requirements have been limited. GAO's discussions with DOE and laboratory management contractors uncovered only 14 instances in which the laboratories' intellectual property were involved in offset projects. GAO also found that management contractors have the right to intellectual property that they produce at DOE laboratories."

This report provides the results of a random survey of adult Texas residents aged 18 and older to measure the citizen participation rates, the distribution and frequency of play, and the demographic profiles of the past-year lottery players and non-players.

Correspondence issued by the General Accounting Office with an abstract that begins "GAO examined the military's inventory management activities to determine if activity codes identified as unauthorized to requisition had been used to buy property for the Air Force. GAO found that as of June 2000, the Air Force maintained 4,239 activity codes identified as unauthorized to requisition government property. However, during the last five years, 193 of these codes were inappropriately used to requisition nearly $23 million in new and excess government property. In addition, safeguards established to prevent unauthorized activity codes from being used to requisition government property failed. This situation has created a condition in which government property is vulnerable to waste, fraud, and abuse."

Correspondence issued by the General Accounting Office with an abstract that begins "GAO examined Navy inventory management activities to determine whether any unauthorized activity codes had been used to requisition new and excess property. GAO found that as of June 2000, the Navy maintained 2,002 activity codes identified as unauthorized to requisition government property. However, during the last five years, 663 of these codes were used to requisition more than $2 billion in new and excess government property. In addition, there were no safeguards in the Defense Automatic Addressing System Center or the Defense Reutilization and Marketing Service to prevent these activity codes from being used. This has created a condition in which government property is vulnerable to waste, fraud, and abuse."

This report provides technical documentation for values in the Table of Initial Isolation and Protective Action Distances (PADs) in the ''2000 Emergency Response Guidebook'' (2000ERG). The objective for choosing the PADs specified in the 2000ERG was to balance the need to adequately protect the public from exposure to potentially harmful substances against the risks and expenses that could result from overreacting to a spill. To quantify this balance, a statistical approach was adopted, whereby the best available information was used to conduct an accident scenario analysis and develop a set of up to 100,000 hypothetical incidents. The set accounted for differences in the types of containers, types of incidents, severities of accidents (i.e., amounts released), locations, times of day, times of year, and meteorological conditions involved. Each scenario was analyzed by using detailed emission rate and atmospheric dispersion models to calculate the downwind chemical concentrations. The safe distance for each incident, defined as the distance downwind from the source at which the chemical concentration falls below the health criteria, was determined. The health criteria used were the American Industrial Hygiene Association's Emergency Response Planning Guideline Level 2 (ERPG-2) or equivalent criteria. The statistical sample of safe distance values for all …

Title I, Part A of the Elementary and Secondary Education Act (ESEA) authorizes federal aid to state and local educational agencies (SEAs, LEAs) for the education of disadvantaged children. Title I grants are used to provide supplementary educational and related services to low-achieving children attending schools with relatively high concentrations of pupils from low-income families. Services may be provided at pre-kindergarten through high school levels. Title I has been the anchor of the ESEA since it was first enacted in 1965, and is the largest federal elementary and secondary education assistance program.

This report discusses issues regarding Agriculture funding, specifically the Federal Agriculture Improvement and Reform (FAIR) Act (P.L. 104-127), which prescribed farm commodity support policy through 2002.

Correspondence issued by the General Accounting Office with an abstract that begins "As of June 2000, the General Services Administration (GSA) maintained 52 activity codes identified as unauthorized to requisition government property. During the last five years, four of these codes were inappropriately used to requisition about $3,000 in new and excess government property. Although this amount represents a small percentage of total GSA requisitions made during the five-year period, existing safeguards are inadequate to prevent the use of unauthorized activity codes to requisition government property. GSA is now tracing the various items."

The Generalized System of Preferences (GSP) extends duty-free treatment to certain products that are imported from designated developing countries. The primary purpose of the program, which the United States and other industrial countries initiated in the 1970s, is to promote economic growth and development in these countries by stimulating their exports. The program was reauthorized by the 106th Congress, retroactively from July 1, 1999, through September 30, 2001. The 107th Congress will face the issue of whether to reauthorize GSP.

This document contains the CY 2001 schedules for the routine collection of samples for the Surface Environmental Surveillance Project (SESP) and Drinking Water Monitoring Project. Each section includes sampling locations, sample types, and analyses to be performed.

This document contains the CY 2001 schedules for the routine collection of samples for the Surface Environmental Surveillance Project (SESP) and Drinking Water Monitoring Project. Each section includes sampling locations, sample types, and analyses to be performed.

Hosting a Showcase Demonstration Event describes how industrial manufacturers can showcase energy efficiency technologies that they have implemented in their plants. Companies can gain access to a wide variety of technical assistance and resources when they agree to host a showcase demonstration and this fact sheet explains how to participate.

This report provides an analysis of issue involving the application of information technology to elementary and secondary education, and federal policy making in this area.

CRS Report for Congress entailing information about the current status and federal report of information technology and elementary and secondary education. Topics include, recent action, major issues, federal policy questions etc..

Computational models of particle dynamics often exchange solution data with discretized continuum-fields using interpolation functions. These particle methods require a series expansion of the interpolation function for two purposes: numerical analyses used to establish the models consistency and accuracy, and logical-coordinate evaluation used to locate particles within a grid. This report presents a new method of developing discrete-expansions for interpolation; they are similar to multi-variable expansions but, unlike a Taylor's series, discrete-expansions are valid throughout a discretized domain. Discrete-expansions are developed herein by parametrically integrating the interpolation function's total-differential between two particles located within separate, non-contiguous cells. Discrete-expansions are valid for numerical analyses since they acknowledge the functional dependence of interpolation and account for mapping discontinuities across cell boundaries. The use of discrete-expansions for logical-coordinate evaluation provides an algorithmically robust and computationally efficient particle localization method. Verification of this new method is demonstrated herein on a simple test problem.

Some recent work has been done to look at improvements of transporting beam from the Lithium Lens to the Debuncher. This work has been done using the beamline modeling tools developed by Dave McGinnis. These tools, console application P143 and optimization code running MAD repeatedly on the Beam Physics UNIX system, were first used to match the Twiss and dispersion parameters at the end of AP2 to the Debuncher. Imaginary trims were then added to AP2 to study where additional trims could be used to help with beam control in small aperture areas.

Hardware performance counters are CPU registers that count data loads and stores, cache misses, and other events. Counter data can help programmers understand software performance. Although CPUs typically have multiple counters, each can monitor only one type of event at a time, and some counters can monitor only certain events. Therefore, some CPUs cannot concurrently monitor interesting combinations of events. Software multiplexing partly overcomes this limitation by using time sharing to monitor multiple events on one counter: However; counter multiplexing is harder to implement for multithreaded programs than for single-threaded ones because of certain difficulties in managing the length of the time slices. This paper describes a software library called MPX that overcomes these difficulties. MPX allows applications to gather hardware counter data concurrently for any combination of countable events. MPX data are typically within a few percent of counts recorded without multiplexing.

This report details a quantitative risk assessment conducted for transportation of selected hazardous materials on a national basis. These materials include six toxic-by-inhalation (TIH) chemicals, which account for more than 90% of the total TIH transportation-related risk; liquefied petroleum gas; gasoline; and explosives. For TIH materials, both highway and rail transportation are considered, and two classes of incidents are examined--those that occur (1) during a traffic accident or a train derailment and (2) while en route from the origin to the destination, but not during an accident or derailment. For the other materials evaluated in the study, only accident-related incidents for highway transportation are considered because transportation-related risk for these materials is dominated by highway incidents. The report describes the hazardous materials and consequence levels evaluated; the risk assessment methodology; the databases used to determine hazardous materials commodity flow and incident rates; and results of the study, including quantitative risk distributions and risk measures for the materials evaluated. The results suggest that, compared with other types of transportation risks encountered by the public, overall societal risks due to hazardous materials transportation remain relatively low. However, the potential exists for very serious accidents involving large numbers of injuries and fatalities, especially …

Increasingly in industry, software design and implementation is object-oriented, developed in C++ or Java, and relies heavily on pre-existing software libraries (e.g. the Microsoft Foundation Classes for C++, the Java API for Java). A similar but more tentative trend is developing in high-performance parallel scientific computing. The transition from serial to parallel application development considerably increases the need for library support: task creation and management, data distribution and dynamic redistribution, and inter-process and inter-processor communication and synchronization must be supported. PADRE is a library to support the interoperability of parallel applications. We feel there is significant need for just such a tool to compliment the many domain-specific application frameworks presently available today, but which are generally not interoperable.