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We consider a variation of the Cops and Robber game where the cops can only see the robber when the distance between them is at most a fixed parameter $\ell$. We consider the basic consequences of this definition for some simple graph families, and show that this model is not monotonic, unlike common models where the robber is invisible. We see that cops' strategy consists of a phase in which they need to "see" the robber (move within distance $\ell$ of the robber), followed by a phase in which they capture the robber. In some graphs the first phase is the most resource intensive phase (in terms of number of cops needed), while in other graphs, it is the second phase. Finally, we characterize those trees for which $k$ cops are sufficient to guarantee capture of the robber for all $\ell \ge 1$., Comment: 22 pages

This publication contains some techniques, practices, and information homeowners can use for new or existing homesites to reduce their susceptibility to damage from wildfires and related flooding events.

The efficacy of the UK candidate plague vaccine was established in the cynomolgus macaque model for pneumonic plague. Animals were vaccinated intramuscularly on days 0 and 21 with either 40 g F1 + 40 g V or 80 g F1 + 80 g V in 0.5 ml 20% v/v Alhydrogel. They were challenged on day 60 with a lethal aerosol challenge (> 100 LD50) of CO 92 Y. pestis. All but one of the 19 vaccinated animals that were challenged survived., The original document contains color images.

This publication contains some techniques, practices, and information homeowners can use for new or existing homesites to reduce their susceptibility to damage from wildfires and related flooding events.

This report describes an investigation of the performance of air-augmented waterjet thrusters. The investigation is divided into two parts. Part 1 describes a study of the injection of large diameter air bubbles to reduce heat transfer between the air and water and, thus, increase the thrust. This study is done analytically by solving the appropriate, governing equations. The results indicate that the approach is very worth-while since thrust can be increased ten percent as compared to air-augmentation with small bubbles. Several practical systems are discussed for injecting large air bubbles. Part 2 in an experimental investigation of the thrust produced under a wind range of conditions. The results show that a thrust increase of more than 20% can be achieved by air-augmentation. Further, the performance improves for larger thrust nozzles. (Author)

Polystyrene bead foam (PSBF) was evaluated as an encapsulant for electronic packages. Various properties of PSBF pertinent to the expected environmental conditioning of a prototype electronic package were determined and evaluated for their effects on individual electronic components, within the package. It was determined that PSBF densities of 0.2 to 0.4 g/cm3 provided adequate protection without damaging fragile electronic components. PSBF densities above 0.4 g/cm3 provide adequate protection from the shock and vibration spectra evaluated, but could damage fragile electronic components during the encapsulation process and thermal cycling. Buildup of electrostatic voltage during encapsulation can be reduced to safe levels by grounding the case of the electronic package. Only the 0.6 g/cm3 PSBF could be made impervious to moisture penetration. (AN)

The report describes an investigation of the performance of a gas-augmented waterjet propulsion system. The study was divided into three parts. First, an analytical investigation was conducted to determine the performance of air-augmented waterjet thrust nozzles. Also, comparisons were made between equations from the literature for the local sonic velocity and the sonic velocity predicted by the analysis. An experimental investigation was performed to determine the validity of the model development in the first part. The agreement between analysis and experiment was good for low air-water ratios. The third part of the report describes a study used to estimate the overall performance of a gas-augmented propulsion system. Several parameters were varied to determine their effect upon the performance. (Author)