We review both classical and quantum potential scattering in two dimensions in a magnetic field, with applications to the quantum Hall effect. Classical scattering is complex, due to the approach of scattering states to an infinite number of dynamically bound states. Quantum scattering follows the classical behavior rather closely, exhibiting sharp resonances in place of the classical bound states. Extended scatterers provide a quantitative explanation for the breakdown of the QHE at a comparatively small Hall voltage as seen by Kawaji et al., and possibly for noise effects.

The Temperature-Initiated Passive Cooling System (TIPACS) is a recently invented passive cooling system that transfers heat from a hot, insulated system to a cooler, external environment. TIPACS has four defining characteristics: efficient heat-transfer, passive with no moving components, thermal switch mechanism that allows heat transfer only above a preset temperature, and one-way (heat diode) heat transfer. Example applications include cooling (1) building attics, (2) electrical sheds, (3) chemical reactors, (4) utility-load-leveling batteries, and (5) nuclear reactor containments. TIPACS was evaluated for cooling a modular high-temperature gas-cooled reactor (MHTGR) cavity. This evaluation indicates potential performance and economic advantages.

The physical state of the debris cloud generated by the interaction of a projectile with a thin target depends on the energy balance associated with above the sound speeds of the impact event. At impact velocities well materials involved, the cloud is expected to be primarily molten, but with some vapor present. A series of numerical calculations using the multi-dimensional finite-difference hydrocode CTH has been used to evaluate the effect of phase changes (i.e., different vapor fractions) on these clouds, and their subsequent interaction with backwall structures. In the calculations, higher concentrations of vapor are achieved by increasing the initial temperature of both the projectile and the thin shield while keeping the impact velocity constant, and by actually increasing the impact velocity. The nature of the debris cloud and its subsequent loading on the protected structure depend on both its thermal and physical state. This interaction can cause rupture, spallation or simply bulging of the backwall. These computational results are discussed and compared with new experimental observations obtained at an impact velocity of {approximately}10 km/s. In the experiment, the debris cloud was generated by the impact of a plate-shaped titanium projectile with a thin titanium shield.

The centralized audio presentation manager addresses the problems which occur when multiple programs running simultaneously attempt to use the audio output of a computer system. Time dependence of sound means that certain auditory messages must be scheduled simultaneously, which can lead to perceptual problems due to psychoacoustic phenomena. Furthermore, the combination of speech and nonspeech audio is examined; each presents its own problems of perceptibility in an acoustic environment composed of multiple auditory streams. The centralized audio presentation manager receives abstract parameterized message requests from the currently running programs, and attempts to create and present a sonic representation in the most perceptible manner through the use of a theoretically and empirically designed rule set.

The authors present an observational and theoretical review of the winds of cataclysmic variables (CVs). Specifically, they consider the related problems of the geometry and mass-loss rate of the winds of CVs, their ionization state and variability, and the results from studies of eclipsing CVs. Finally, they consider the properties of accretion disk wind models. Some of these models predict substantial angular momentum loss, which could affect both disk structure and binary evolution.

The mission of the National Ignition Facility is to achieve ignition and gain in inertial confinement fusion targets in the laboratory. The facility will be used for defense applications such as weapons physics and weapons effects testing, and for civilian applications such as fusion energy development and fundamental studies of matter at high temperatures and densities. This paper reviews the design, schedule, and costs associated with the construction project.

A conceptual design for the National Ignition Facility (NIF) has been completed and its cost has been estimated by a multilaboratory team. To maximize the performance/cost ratio a compact, segmented amplifier is used in a multipass architecture. Many recent optical and laser technology developments have been incorporated into the final design. The Beamlet project has successfully demonstrated the new concept. The mission of ICF Program using the NEF is to achieve ignition and gain in the laboratory. The facility will be used for defense applications such as weapons physics and weapons effects experiments, and for civilian applications such as inertial fusion energy development and fundamental studies of matter at high energy density.

Future colliding beam runs at Fermi National Accelerator Laboratory will involve bunch spacings of protons and antiprotons at 132 ns intervals. Due to finite processing time, a pipelined architecture is needed to store events until a trigger decision can reach the detector. A single ported pipeline design has been implemented in a 1.2 micron rad soft CMOS technology and partially tested. Results are presented of the performance of that design. The chip supports a level 1 accept rate of 5 kHz. Because high statistics B physics experiments will require level 1 accept rates of 50 kHz, a new dual ported pipeline device has been proposed which would make the readout virtually deadtimeless for trigger rates approaching 50 kHz. The operation of the proposed deadtimeless device is explained.

This paper presents the personal views of the author on the subject of the proposed Chemical Weapons Convention (CWC). She addresses here concerns about the national security issues which could result from ratification of this convention. She argues the convention alone is not likely to curtail production or availability of such items on the world market because of the relatively low cost. The treaty could thus put the country in a position less likely to protect itself, or adequately deal with such a threat.

Results from CDF on W{sup +}W{sup {minus}}, WZ, and W{gamma} production in {radical}s = 1.8 TeV {bar p}-p collisions from the 1992--1993 collider run are presented. Direct limits on WW{gamma} and WWZ anomalous couplings are obtained.

Article on theoretical studies of the RSOO, ROSO, RSO2 and HOOS (R=H, CH3) radicals.

It is shown that, despite the poor global energy confinement observed in spheromak experiments to date, the long-term prospects may be favorable as spheromaks are scaled to larger size and higher temperatures. The present performance is traced to excessive magnetic energy loss at the edge compared to tokamaks and heat transport due to magnetic fluctuations, both of which should scale away as the temperature increases.

The mission of the National Ignition Facility is to achieve ignition and gain in ICF targets in the laboratory. The facility will be used for defense applications such as weapons physics and weapons effect testing, and for civilian applications such as fusion energy development and fundamental studies of matter at high temperatures and densities. This paper reviews the design, schedule and costs associated with the construction project.