USB flow characteristics related to noise generation

The effects of nozzle and flap geometry on upper surface blown flow field characteristics related to noise generation were examined experimentally using static models. Flow attachment and spreading characteristics were observed using flow visualization techniques. Velocity and turbulence profiles in the trailing edge wake were measured using hot-wire anemometry, and the effects of the geometric variables on peak velocity and turbulence intensity were determined. It is shown that peak trailing edge velocity is a function of the ratio of flow length to modified hydraulic diameter

Minimizing Vessel Strikes to Endangered Whales: A Crash Course in Conservation Science and Policy

The North Atlantic right whale is one of the most endangered of all large whales: about 350-400 individuals remain. Species recovery is, in part, contingent on reducing vessel-strike mortality. Our science-based conservation program resulted in three efforts specifically designed to minimize the risk of lethal vessel-strikes of endangered baleen whales without compromising vessel navigation and safety. In Atlantic Canada, the Bay of Fundy Traffic Separation Scheme (TSS) was relocated to reduce the risk of lethal vessel strikes by 90% where the original outbound lane of the TSS intersected the Right Whale Conservation Area, and an Area To Be Avoided (ATBA) adopted for Roseway Basin has demonstrated an 82% reduction in the risk of lethal vessel-strikes. In the Gulf of Maine, the Boston TSS through the Stellwagen Bank National Marine Sanctuary was relocated to reduce the overlap between vessels and endangered baleen whales by ~81% and by ~58% for right whales alone. This rerouting of vessels for whale conservation, as sanctioned by the International Maritime Organization, sets a precedent for national and international marine conservation policy by providing vessels with direct actions they can take to protect endangered whales – both regulated (TSS) and voluntary (ATBA). This demonstrate that despite contentious conditions, effective science-driven policy tools for conservation can be identified, made available, and implemented. The science also provides the quantitative means to measure policy efficacy through monitoring of vessel compliance and, in some cases, can increase compliance through improved real-time communications regarding whale locations in high-risk areas

Nuclear reactor descriptions for space power systems analysis

For the small, high performance reactors required for space electric applications, adequate neutronic analysis is of crucial importance, but in terms of computational time consumed, nuclear calculations probably yield the least amount of detail for mission analysis study. It has been found possible, after generation of only a few designs of a reactor family in elaborate thermomechanical and nuclear detail to use simple curve fitting techniques to assure desired neutronic performance while still performing the thermomechanical analysis in explicit detail. The resulting speed-up in computation time permits a broad detailed examination of constraints by the mission analyst

Life Science Payloads Planning Study Integration Facility Survey: Executive Summary

Analyses of proposed life science shuttle era payload operations are discussed. A summary of results from a survey conducted to: (1) examine facility and equipment resources needed for life science payload integration, checkout, test and mission support activities; (2) identify presently available resources; and (3) determine methods by which operational era status may be implemented based on currently available resources, is presented

Life science payloads planning study integration facility survey results

The integration facility survey effort described is structured to examine the facility resources needed to conduct life science payload (LSP) integration checkout activities at NASA-JSC. The LSP integration facility operations and functions are defined along with the LSP requirements for facility design. A description of available JSC life science facilities is presented and a comparison of accommodations versus requirements is reported

On a conjecture of Bennewitz, and the behaviour of the Titchmarsh-Weyl matrix near a pole

For any real limit-$n$ $2n$th-order selfadjoint linear differential expression on $[0,\infty)$, Titchmarsh- Weyl matrices $M(\lambda)$ can be defined. Two matrices of particu lar interest are the matrices $M_D(\lambda)$ and $M_N(\lambda)$ assoc iated respectively with Dirichlet and Neumann boundary conditions at $x=0$. These satisfy $M_D(\lambda) = -M_{N}(\lambda)^{-1}$. It is known that when these matrices have poles (which can only lie on the real axis) the existence of valid HELP inequalities depends on their behaviour in the neighbourhood of these poles. We prove a conjecture of Bennewitz and use it, together with a new algorithm for computing the Laurent expansion of a Titchmarsh-Weyl matrix in the neighbourhood of a pole, to investigate the existence of HELP inequalities for a number of differential equations which have so far proved awkward to analys

Russian Federation - The myth of monopoly : a new view of industrial structure in Russia

Discussion of economic reform in the Russian Federation is colored by the conventional view of Russia's industrial structure. Both in Russia and in the West, Russian industry is characterized as very large enterprises operating in highly concentrated industries. The authors challenge the conventional view. They assess Russian industrial concentration by comparing the Russian industrial structure (as revealed in the 1989 Soviet Census of Industry) with that in the United States and other countries. They find that very large firms are more prevalent in the United States than in Russia. This empirical fact suggests that planners economized on the costs of central economic coordination not by building unusually large enterprises, but by not building very small enterprises. Their most important finding: that there is little aggregate or industry concentration at the national level in Russia. Monopolies and oligopolies actually account for only a small share of national employment and production. Instead, barriers to competition in Russia arise as a result of highly segmented product markets. In large part, this segmentation can be viewed as a legacy of central planning. Under the prior regime, enterprises were highly isolated, divided alone both ministerial and geographical lines. Presently, these barriers are reinforced by some features of the transitional environment that continue to undermine the efficient distribution of goods. The authors conclude that the traditional policy remedies appropriate for problems of concentration (such as antitrust policy and import competition) may be ill-advised or inadequate for addressing problems of imperfect competition in the Russian economy. They argue instead that improving the distribution system and other market infrastructure that supports trade and facilitating the entry of new firms should be the most critical elements of competition policy in Russia.Microfinance,Small Scale Enterprise,Private Participation in Infrastructure,Banks&Banking Reform,Water and Industry

Pilot interaction with automated airborne decision making systems

The use of advanced software engineering methods (e.g., from artificial intelligence) to aid aircraft crews in procedure selection and execution is investigated. Human problem solving in dynamic environments as effected by the human's level of knowledge of system operations is examined. Progress on the development of full scale simulation facilities is also discussed

Studies related to ocean dynamics. Task 3.2: Aircraft Field Test Program to investigate the ability of remote sensing methods to measure current/wind-wave interactions

The feasibility of remote sensing of current flows in the ocean and the remote sensing of ocean currents by backscattering cross section techniques was studied. It was established that for capillary waves, small scale currents could be accurately measured through observation of wave kinematics. Drastic modifications of waves by changing currents were noted. The development of new methods for the measurement of capillary waves are discussed. Improvement methods to resolve data processing problems are suggested