A conceptual design for ITER was completed last year. The author developed a suitable cryogenic system for ITER as part of this conceptual design effort. An overview of the design is reported. Emphasis is on the fact that cryogenics is a mature science, and a system supporting ITER needs can be made from time-proven components without loss of efficiency or reliability. Because of the large size of the ITER cryogenic system, large numbers of compressors and expanders must be used. Very high reliability is assured by arranging these components in parallel banks where servicing of individual components can be done without interruption of operations. This and other ideas based on the author's experience with Mirror Fusion Test Facility (MFTF) operations are described. 5 refs., 3 figs.

The relation between the parameters of a differential equation and corresponding discrete maps are becoming increasingly important in the study of nonlinear dynamical systems. Maps are well adopted for numerical computation and several universal properties of them are known. Therefore some perturbation methods have been proposed to deduce them for physical systems, which can be modeled by an ordinary differential equation (ODE) with a small nonlinearity. A new iterative, rigorous algebraic method for the calculation of the coefficients of a Taylor expansion of a stroboscopic map from ODE's with not necessarily small nonlinearities is presented. It is shown analytically that most of the coefficients are small for a small integration time and grow slowly in the course of time if the flow vector field of the ODE is polynomial and if the ODE has fixed point in the origin. Approximations of different orders respectively of the rest term are investigated for several nonlinear systems. 31 refs., 16 figs.

The stability margins of the US-Demonstration Poloidal Coil (US-DPC) and the International Thermonuclear Experimental Reactor (ITER) TF coils have been modeled numerically using the computer program CICC. The computed US-DPC limiting current, I{sub lim}, compares favorably with the values determined experimentally. Using the detailed program CICC output, we investigated the DPC quench initiation mechanism in each of the three stability regions. In the ill-cooled region, the imposed heat pulse heats the conductor to the current-sharing temperature, T{sub cs}. In the transition region, the resistance heating after the pulse must be strong enough to overcome the induced flow reversal. In the well-cooled region, good heat transfer heats the helium during the pulse. After the pulse, these high helium temperatures along with poor heat transfer cause the conductor to quench. Changes in I{sub lim} agree with Dresner's relationship. I{sub lim} can be improved by decreasing the copper resistivity, the helium fraction, or the conductor diameter. Preliminary results show the ITER and TF coil operating point is in the well-cooled region. 10 refs., 7 figs., 1 tab.

A conceptual design has been developed for a reference current drive and heating system for a HARD (High Aspect Ratio Design) option for ITER. Twelve neutral beam modules, each rated at 1.3MeV and 9.2MW, perform plasma heating and current drive. An electron cyclotron system is used for initiating the plasma and for disruption control. An alternate system has been defined which is comprised of a lower hybrid and ion cyclotron system for heating and current drive, augmented by the same electron cyclotron system proposed for the reference system. 7 refs., 8 figs., 1 tab.

The performance of a Cray system is highly dependent on the tuning techniques used by individuals on their codes. Many of our users were not taking advantage of the tuning tools that allow them to monitor their own programs by using the Hardware Performance Monitor (HPM). We therefore modified UNICOS to collect HPM data for all processes and to report Mflop ratings based on users, programs, and time used. Our tuning efforts are now being focused on the users and programs that have the best potential for performance improvements. These modifications and some of the more striking performance improvements are described.

The Network File System (NFS) is used in UNIX-based networks to provide transparent file sharing between heterogeneous systems. Although NFS is well-known for being weak in security, it is widely used and has become a de facto standard. This paper examines the user authentication shortcomings of NFS and the approach Sandia National Laboratories has taken to strengthen it with Kerberos. The implementation on a Cray Y-MP8/864 running UNICOS is described and resource/performance issues are discussed. 4 refs., 4 figs.

An Environmental Protection Agency (EPA) approved sampling and analysis protocol was developed and executed to verify atmospheric emissions compliance for the new Savannah River Site (SRS) F/H area Effluent Treatment Facility. Sampling equipment was fabricated, installed, and tested at stack monitoring points for filtrable particulate radionuclides, radioactive iodine, and tritium. The only detectable anthropogenic radionuclides released from Effluent Treatment Facility stacks during monitoring were iodine-129 and tritium oxide. This paper only examines the collection and analysis of tritium oxide.

This document reviews some recent work on physics simulations for SSC/LHC. Included are reviews of some of the recent developments in physics simulations for the SSC/LHC and comments upon the requirements that are placed upon detectors by the need to extract specific physics signatures. The material in the various EOI/LOI documents submitted to the SCC Laboratory and the work done at the Aachen LHC workshop are discussed. In the following discussion 1 SSC (LHC) year corresponds to an integrated luminosity of 10 (100) fb{sup {minus}1}. 41 refs., 14 figs.

We review models for spin-weighted parton distributions in a proton. Sum rules involving the nonsinglet components of the structure function xg{sub 1}{sup p} help narrow the range of parameters in these models. The contribution of the {gamma}{sub 5} anomaly term depends on the size of the integrated polarized gluon distribution and experimental predictions depend on its size. We have proposed three models for the polarized gluon distributions, whose range is considerable. These model distributions give an overall range is considerable. These model distributions give an overall range of parameters that can be tested with polarized beam experiments. These are discussed with regard to specific predictions for polarized beam experiments at energies typical of UNK.

The oceans play a critical role in regulating the global carbon cycle. Deep-ocean waters are roughly 200% supersaturated with CO{sub 2} compared to surface waters, which are in contact with the atmosphere. This difference is due to the flux of photosynthetically derived organic material from surface to deep waters and its subsequent remineralization, i.e. the biological pump''. The pump is a complex phytoplankton-based ecosystem. the paradoxical nature of ocean regions containing high nutrients and low phytoplankton populations has intrigued biological oceanographers for many years. Hypotheses to explain the paradox include the regulation of productivity by light, temperature, zooplankton grazing, and trace metal limitation and/or toxicity. To date, none of the hypotheses, or combinations thereof, has emerged as a widely accepted explanation for why the nitrogen and phosphorus are not depleted in these regions of the oceans. Recently, new evidence has emerged which supports the hypothesis that iron limitation regulates primary production in these areas. This has stimulated discussions of the feasibility of fertilizing parts the Southern Ocean with iron, and thus sequestering additional atmospheric CO{sub 2} in the deep oceans, where it would remain over the next few centuries. The economic, social, and ethical concerns surrounding such a proposition, along …

On August 14, 1992, the United States Department of Energy issued a Request for Comments Concerning State Policies Affecting Natural Gas Consumption. This Notice of (NOI) noted the increasing significance of the role played by states and sought to gain better understanding of how state policies impact the gas industry. The general trend toward a. more competitive marketplace for natural gas, as well as recent regulatory and legislative changes at the Federal level, are driving State regulatory agencies to reevaluate how they regulate natural gas. State action is having a significant impact on the use of natural gas for generating electricity, as well as affecting the cost-effective trade-off between conservation expenditures and gas use. Additionally, fuel choice has an impact upon the environment and national energy security. In light of these dimensions, the Department of Energy initiated this study of State regulation. The goals of this NOI are: (1) help DOE better understand the impact of State policies on the efficient use of gas; (2) increase the awareness of the natural gas industry and Federal and State officials to the important role of State policies and regulations; (3) create an improved forum for dialogue on State and Federal natural gas …

We are carrying out an integrated program of laboratory experiments, kinetics modeling, and basin thermal history modeling in order to better understand the natural breakdown of organic matter into oil and gas. Our kinetic models of organic maturation are being used to better understand the coupling of generation, cracking, expulsion, and overpressuring in both the laboratory and geologic setting. Currently we are carrying out chemical experiments and developing more efficient chemical kinetic modeling schemes to obtain a better understanding of expulsion and cracking from lean source rocks and from hydrogen-poor (terrestrial) organic source material. We verify the chemical kinetic models by integrating them with thermal history models of hydrocarbon-producing sediments and comparing predicted and observed characteristics of the hydrocarbon occurrence in a variety of settings. We intend to apply this approach to evaluate the potential for deep gas resources in the Pacific Northwest and in the Louisiana Gulf Coast. 11 refs., 4 figs.

An article in The Dallas Morning News that was written by Shermakaye Bass that discusses different university programs and art groups. The UNT NTIEVA and Dallas Museum of Art pairing is one of the featured groups.

The amount of data generated by CT scanners is enormous, making the reconstruction operation slow, especially for 3-D and limited-data scans requiring iterative algorithms. The Radon transform and its inverse, commonly used for CT image reconstruction from projections, are computationally burdensome for today's single-processor computer architectures. If the processing times for the forward and inverse Radon transforms were comparatively small, a large set of new CT algorithms would become feasible, especially those for 3-D and iterative tomographic image reconstructions. In addition to image reconstruction, a fast Radon Transform Computer'' could be naturally applied in other areas of multidimensional signal processing including 2-D power spectrum estimation, modeling of human perception, Hough transforms, image representation, synthetic aperture radar processing, and others. A high speed processor for this operation is likely to motivate new algorithms for general multidimensional signal processing using the Radon transform. In the proposed workshop paper, we will first describe interpolation schemes useful in computation of the discrete Radon transform and backprojection and compare their errors and hardware complexities. We then will evaluate through statistical means the fixed-point number system required to accept and generate 12-bit input and output data with acceptable error using the linear interpolation scheme selected. These …

We use a newly developed real-space multiple scattering theory (RS-MST) to calculate low-energy electron diffraction (LEED) intensities from stepped surfaces. In this calculation the electron wavefunctions are expanded in terms of an angular momentum basis, utilizing the property of removal invariance of systems with semi-infinite periodicity. This strongly reduces the dependence of the calculation on the interlayer spacing and thus opens up the possibility of treating more open surfaces. This includes in particular stepped surfaces, to which conventional methods cannot be applied. Applications of the formalism to various stepped surfaces are presented. In particular, the results for Cu(311) and (331) surfaces obtained from both the layer doubling and RS-MST methods are compared. In addition, numerical techniques which can improve the convergence as well as the speed of the RS-MST approach are discussed. 6 refs., 3 figs.

This report presents the closing talk of the workshop on AGS heavy ion program held at BNL March 5--7, 1990. The emphasis is on new questions posed by the new data presented at this meeting with emphasis on the pion-proton puzzle. 10 refs., 1 fig., 1 tab.

Programs to develop solid core nuclear thermal propulsion (NTP) systems have been under way at the Department of Defense (DoD), the National Aeronautics and Space Administration (NASA), and the Department of Energy (DOE). These programs have recognized the need for a new ground test facility to support development of NTP systems. However, the different military and civilian applications have led to different ground test facility requirements. The Department of Energy (DOE) in its role as landlord and operator of the proposed research reactor test facilities has initiated an effort to explore opportunities for a common ground test facility to meet both DoD and NASA needs. The baseline design and operating limits of the proposed DoD NTP ground test facility are described. The NASA ground test facility requirements are reviewed and their potential impact on the DoD facility baseline is discussed.

On August 14, 1992, the United States Department of Energy issued a Request for Comments Concerning State Policies Affecting Natural Gas Consumption. This Notice of (NOI) noted the increasing significance of the role played by states and sought to gain better understanding of how state policies impact the gas industry. The general trend toward a. more competitive marketplace for natural gas, as well as recent regulatory and legislative changes at the Federal level, are driving State regulatory agencies to reevaluate how they regulate natural gas. State action is having a significant impact on the use of natural gas for generating electricity, as well as affecting the cost-effective trade-off between conservation expenditures and gas use. Additionally, fuel choice has an impact upon the environment and national energy security. In light of these dimensions, the Department of Energy initiated this study of State regulation. The goals of this NOI are: (1) help DOE better understand the impact of State policies on the efficient use of gas; (2) increase the awareness of the natural gas industry and Federal and State officials to the important role of State policies and regulations; (3) create an improved forum for dialogue on State and Federal natural gas …

Argonne National Laboratory`s Analysis & Diagnostic Laboratory (ADL) tests advanced batteries under simulated electric and hybrid vehicle operating conditions. The ADL facilities also include a post-test analysis laboratory to determine, in a protected atmosphere if needed, component compositional changes and failure mechanisms. The ADL provides a common basis for battery performance characterization and life evaluations with unbiased application of tests and analyses. The battery evaluations and post-test examinations help identify factors that limit system performance and life, and the most-promising R&D approaches for overcoming these limitations. Since 1991, performance characterizations and/or life evaluations have been conducted on eight battery technologies (Na/S, Li/S, Zn/Br, Ni/MH, Ni/Zn, Ni/Cd, Ni/Fe, and lead-acid). These evaluations were performed for the Department of Energy`s. Office of Transportation Technologies, Electric and Hybrid Propulsion Division (DOE/OTT/EHP), and Electric Power Research Institute (EPRI) Transportation Program. The results obtained are discussed.

Starting in 1989, the concept that partitioning and transmuting actinides from spent nuclear fuel could be a {open_quotes}solution{close_quotes} to the apparent lack of progress in the high-level waste disposal program began to be heard from a variety of sources, both in the US and internationally. There have been numerous papers and sessions at scientific conferences and several conferences devoted to this subject in the last three years. At the request of the US Department of Energy, the National Research Council is evaluating the feasibility of this concept. Because either plutonium or highly enriched uranium is needed to startup breeder reactors, there is a sound rationale for using Pu from reprocessing spent light-water reactor fuel to start a conversion to Pu-breeding liquid metal reactors (LMRs), once society makes the determination that adding a large component of LMRs to the electricity-generating grid is desirable. This is the long-term option referred to in the title. It is compatible with the current and likely future high-level waste program, as well as the current nuclear power industry in the US. However, the thesis of this paper is that partitioning and transmutation (P-T) does not offer a near term solution to high-level waste disposal in the …

Silica aerogel consists of bonded silicon and oxygen joined into log strands, which are randomly linked together with pockets of air between them. Discovered in the 1930s, the material was thought to have little use outside of theoretical science. However, with the advent of greatly improved processing techniques, such as those developed at Lawrence Livermore National Laboratory, aerogels are on the verge of commercialization. This document describes the need for aerogels in the high-speed microelectronics industry, and state of the art processing techniques. Collaboration is welcomed in the endeavor.

The GEM EM calorimeter is optimized for the best energy, position, angular resolution and jet rejection. The detailed simulation results are presented. In the barrel with LKr, an energy resolution of about 6%/{radical}{direct_sum}0.4%, pointing resolution of 40mrad/{radical}E + 0.5mrad, and jet rejection of a factor of 5 are expected.

While other programs check for bad passwords after the fact, it in important to have good passwords at all times, not just after the latest Crack run. To this end we have modified Larry Wall's Perl password program and added, among other features, the ability to check a sorted list of all the bad passwords'' that Crack will generate, given all the dictionaries that we could get our hands on (107 MB of unique words, so far). The combination of improvements has turned publicly available code into a powerful tool that can aid sites in the maintenance of local security.

An Environmental Protection Agency (EPA) approved sampling and analysis protocol was developed and executed to verify atmospheric emissions compliance for the new Savannah River Site (SRS) F/H area Effluent Treatment Facility. Sampling equipment was fabricated, installed, and tested at stack monitoring points for filtrable particulate radionuclides, radioactive iodine, and tritium. The only detectable anthropogenic radionuclides released from Effluent Treatment Facility stacks during monitoring were iodine-129 and tritium oxide. This paper only examines the collection and analysis of tritium oxide.