We describe a fabrication process used to manufacture high power-to-weight-ratio flexible solar array modules for use on high-altitude-long-endurance (HALE) solar-electric unmanned air vehicles (UAVs). These modules have achieved power-to-weight ratios of 315 and 396 W/kg for 150{mu}m-thick monofacial and 110{mu}m-thick bifacial silicon solar cells, respectively. These calculations reflect average module efficiencies of 15.3% (150{mu}m) and 14.7% (110{mu}m) obtained from electrical tests performed by Spectrolab, Inc. under AMO global conditions at 25{degrees}C, and include weight contributions from all module components (solar cells, lamination material, bypass diodes, interconnect wires, and adhesive tape used to attach the modules to the wing). The fabrication, testing, and performance of 32 m{sup 2} of these modules will be described.

A model of drilling by high radiance pulsed lasers is described. The model involves a one-dimensional description of heat transport below the bottom of the hole, hydrodynamic expansion of the vapor and compressed air, and light propagation through the vapor. The pressure and energy of the vapor are taken from a separate Saha equilibrium code. The boundary conditions at the vaporization surface include the formation of a transition layer within which macroscopic fluid conditions axe reached. The absorption mechanisms are photoionization and inverse bremsstrahlung. The model has been applied to the case of drilling in stainless steel with green copper laser light, for peak input intensities ranging from 10{sup 8} to 4 {times} 10{sup 10} W/cm{sup 2}. Below 3 {times} 10{sup 8} W/cm{sup 2}, there is negligible absorption in the vapor and ablation increases rapidly with intensity. After decreasing for a short interval beyond this point, the ablation rate then increases steadily with power because of a growing electron thermal conduction to the surface. The experimental ablation rate exhibits a somewhat faster overall growth. It appears comparable to the model at low power but is about five times greater at the highest power.

The purpose of the research described in this paper was to examine the effects of using longer and heavier tractor-trailer combinations from the standpoint of the individual firm or shipper rather than from the viewpoint of the motor carrier. The objective was to determine the effect of longer combination vehicles (LCVS) not only on shippers freight costs but on their inventory and other logistical costs as well. A sample of companies in selected industries provided data on their principal products, traffic flows, and logistics costs in a mail survey. These data were entered into a computer program called the Freight Transportation Analyzer (FTA) which calculated the component logistics costs associated with shipping by single trailers and by two alternative types of double trailer LCVS. A major finding of the study was that, given sufficient flows of a company`s product in a traffic lane, LCVs would in most cases greatly reduce the total logistics cost of firms that currently ship in single trailer truckload quantities. Annual lane volume, lane distance, and annual lane ton-mileage appeared to be good indicators of whether or not shipping by LCVs would benefit a company, whereas product value had surprisingly little influence on the cost-effectiveness of …

The following review of the current status of formatted data covariance files and their multigroup processing is a contribution to the IAEA Advisory Group Meeting on ``Improved Evaluations and Integral Data Testing for FENDL,`` to be held at the Max-Planck-Institut fuer Plasmaphysik, Garching, Germany, 12--16 September 1994. The draft agenda of this meeting lists as Item 6 the ``assessment of present status and role of uncertainty files, their processing and sensitivity studies related to FENDL.`` We conclude that this is an important and timely topic and recommend needed actions in this field.

This paper presents an analysis of the applicability of alternative systems for electric vehicle (EV) heating and air conditioning (HVAC). The paper consists of two parts. The first part is a cooling and heating load calculation for electric vehicles. The second part is an evaluation of several systems that can provide the desired cooling and heating in EVs. These systems are ranked according to their overall weight The overall weight is calculated by adding the system weight and the weight of the battery necessary to provide energy for system operation. The system with the minimum overall weight is considered to be the best, because minimum vehicle weight decreases the energy required for propulsion, and therefore increases the vehicle range. Three systems are considered as the best choices for EV HVAC. These are, vapor compression, ice storage and adsorption systems. These systems are evaluated, including calculations of system weight, system volume, and COP. The paper also includes a calculation on how the battery energy storage capacity affects the overall system weights and the selection of the optimum system. The results indicate that, at the conditions analyzed in this paper, an ice storage system has the minimum weight of all the systems …

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Three closely related topics are covered. The derivation of O(g{sup 4}) Lipatov kernels in pure glue QCD. The significance of quarks for the physical Pomeron in QCD. The possible inter-relation of Pomeron dynamics with Electroweak symmetry breaking.

The problem of discriminating between two potential probability models, a Gaussian distribution and a mixture of Gaussian distributions, is considered. The focus of interest is a case where the models are potentially non-nested and the parameters of the mixture model are estimated through the EM algorithm. The AIC, which is frequently used as a criterion for discriminating between non-nested models, is modified to work with the EM algorithm and is shown to provide a model selection tool for this situation. A particular problem involving an infinite mixture distribution known as Middleton`s Class A model is used to demonstrate the effectiveness and limitations of this method. The problem involves a probability model for underwater noise due to distant shipping.

X-ray calibration of the Electro-Optical Breadboard Model (EOBB) of the XXM Reflection Grating Spectrometer has been carried out at the Panter test facility in Germany. The EOBB prototype optics consisted of a four-shell grazing incidence mirror module followed by an array of eight reflection gratings. The dispersed x-rays were detected by an array of three CCDs. Line profile and efficiency measurements where made at several energies, orders, and geometric configurations for individual gratings and for the grating array as a whole. The x-ray measurements verified that the grating mounting method would meet the stringent tolerances necessary for the flight instrument. Post EOBB metrology of the individual gratings and their mountings confirmed the precision of the grating boxes fabrication. Examination of the individual grating surface`s at micron resolution revealed the cause of anomalously wide line profiles to be scattering due to the crazing of the replica`s surface.

The first structural determination with spin-polarized, energy-dependent photoelectron diffraction using circularly-polarized x-rays is reported for Fe films on Cu(001). Circularly-polarized x-rays produced spin-polarized photoelectrons from the Fe 2p doublet, and intensity asymmetries in the 2p{sub 3/2} level are observed. Fully spin-specific multiple scattering calculations reproduced the experimentally-determined energy and angular dependences. A new analytical procedure which focuses upon intensity variations due to spin-dependent diffraction is introduced. A sensitivity to local geometric and magnetic structure is demonstrated.

The authors recently demonstrated the reacceleration of a bunched beam through an induction accelerator cell in support of the two-beam accelerator concept. They present the results of this experiment including amplitude and phase measurements of the extracted microwave power at 11.424 GHz. They also describe progress in achieving a two-beam accelerator microwave source design that is efficient and cost effective for linear collider applications.

The issue of predicting social impacts that could result from the construction and use of new roadways is one that faces, or will face, many communities in the U.S. and throughout the world. Where road development takes place in a scenic area, especially one that is dependent on tourist trade, the nature of the secondary land conversion that often accompanies road construction is especially important. We have assessed the social impacts likely to accompany construction of a scenic parkway in a rural area abutting the Great Smoky Mountains National Park. In this paper, we share the substantive findings of that study as well as our methodological observations on the challenges of projecting impacts in an area that has no planning or zoning, a situation that is common to many rural areas. We also discuss how we dealt with the fact that the major effects of the project would not begin until nearly 15 years in the future, when construction is completed and the roadway is opened to traffic. In order to predict land use patterns at the completion of roadway construction, we studied plat maps, which accurately reflect changing ownership patterns before such changes become apparent on the ground. We …

We propose a method for formation of a long plasma waveguide based on axicon focusing of a radially polarized CO{sub 2} laser pulse into a uniform, low density discharge plasma. simulations demonstrate that an extended cylindrical plasma channel with a wall height {Delta}N{sub e} = 1.5 {times} 10{sup 16}cm{sup {minus}3} will be produced in a DC or RF discharge in 0.17 atm of hydrogen after axicon-focusing of a nanosecond 1-GW/cm{sup 2} CO{sub 2} laser pulse.

By combining a new, all-particle Monte Carlo radiation transport code, PEREGRINE, with the Lawrence Livermore National Laboratory (LLNL) nuclear data base, we have studied the importance of various neutron reactions on dose distributions in biological materials. Monte Carlo calculations have been performed for 5--20 MeV neutron pencil beams incident on biologically relevant materials arranged in several simple geometries. Results highlight the importance of nuclear data used for calculating dose distributions resulting from fast neutron therapy.

This report discusses the following topics: Chromium coating on superconductor strand -- an overview; technology of chromium plating; comparison of wires plated by different platers; search for chromium in copper; strand manufactures` presentations; chromium plating at the Lawrence Livermore National Laboratory; a first look at a chromium plating process development project tailored for T.P.X. and I.T.E.R. strand; and influence of chromium diffusion and related phenomena on the reference ratios of bare and chromium plated Nb{sub 3}Sn strand.

The great library of Alexandria may have contained fewer volumes than the number which have been written on the subject of nuclear weapons in the Cold War. With the end of the Cold War, a new nuclear library is in the making. Much thought is being given to the next steps in nuclear policy, strategy, forces, arms control, and nonproliferation. For this very distinguished conference, however, I have been asked to look further ahead indeed, forward fifty-years. Prognostication is always a risky business. Detailed predictions beyond the shortest duration are difficult to label as ``scientific`` even in the social sciences. Forecasting ahead fifty years in an age of ever accelerating change would seem to be hopeless. Projecting the future of nuclear weapons, however, may not be as complex as one might think. Detailing the future fifty years from now is not necessary. We want to inform upcoming decisions by examining the possibilities, not write a history in advance of what is to happen. Our look forward con benefit from a brief look back fifty years. In retrospect, those years passed quickly, and with each additional year, analysts make them appear more simple than they seemed at the time. This paper …

Clippings from the Denton Record-Chronicle titled 'Vision Denton '94, City builds on education reputation'. The two clippings are part of the same story covering the collaboration of colleges including UNT, museums, and DFW Metroplex area schools. The collaboration offers better art programs and college credit to high schoolers.

We present a selective summary of the discussions on beam-beam-driven synchrobetatron resonances at the 6th Advanced ICFA Beam Dynamics Workshop on the subject ``Synchro-Betatron Resonances,`` held in Funchal (Madeira, Portugal), October 24--30, 1993.