5,885 research outputs found
Funding Cuts to Public Health in Massachusetts: Losses Over Gains
Examines ten public health areas, from children's health to substance abuse, and describes the widening health disparities, reduced data collection, and other effects of budget cuts to programs in prevention, outreach, training, and technical assistance
Advanced photovoltaic solar array development
Phase 2 of the Advanced Photovoltaic Solar Array (APSA) program, started in mid-1987, is currently in progress to fabricate prototype wing hardware that will lead to wing integration and testing in 1989. The design configuration and key details are reviewed. A status of prototype hardware fabricated to date is provided. Results from key component-level tests are discussed. Revised estimates of array-level performance as a function of solar cell device technology for geosynchronous missions are given
The impact of solar cell technology on planar solar array performance
The results of a study into the potential impact of advanced solar cell technologies on the characteristics (weight, cost, area) of typical planar solar arrays designed for low, medium and geosynchronous altitude earth orbits are discussed. The study considered planar solar array substrate designs of lightweight, rigid-panel graphite epoxy and ultra-lightweight Kapton. The study proposed to answer the following questions: Do improved cell characteristics translate into array-level weight, size and cost improvements; What is the relative importance of cell efficiency, weight and cost with respect to array-level performance; How does mission orbital environment affect array-level performance. Comparisons were made at the array level including all mechanisms, hinges, booms, and harnesses. Array designs were sized to provide 5kW of array power (not spacecraft bus power, which is system dependent but can be scaled from given values). The study used important grass roots issues such as use of the GaAs radiation damage coefficients as determined by Anspaugh. Detailed costing was prepared, including cell and cover costs, and manufacturing attrition rates for the various cell types
Polyimide weld bonding for titanium alloy joints
Two weld bonding processes were developed for joining titanium alloy; one process utilizes a weld-through technique and the other a capillary-flow technique. The adhesive used for the weld-through process is similar to the P4/A5F system. A new polyimide laminating resin, BFBI/BMPM, was used in the capillary-flow process. Static property information was generated for weld-bonded joints over the temperature range of 219 K (-65 F) to 561 K (+550 F) and fatigue strength information was generated at room temperature. Significant improvement in fatigue strength was demonstrated for weld-bonded joints over spot-welded joints. A demonstration was made of the applicability of the weld-through weld-bonding process for fabricating stringer stiffened skin panels
Analysis of a communication satellite for lunar far-side exploration
Analysis of communication satellite for lunar far-side exploration relaying color television, voice, high-bit-rate telemetry data, and ranging code from command and service, and lunar module
Devolution: The Retreat of Government
Devolution as practiced in much of the world is decentralization of program authority and responsibility to achieve greater administrative efficiency or program standards. Devolution as practiced by the Bush administration and the Republican Congress is not that, nor is it a diminution of federal power and the strengthening of states’ rights. Rather, it is a radical restructuring of government to prevent the expenditure of funds for traditional Democratic programs of the New Deal and the Great Society, and to prohibit states from being either more generous in social programs or more stringent in regulating industry than this administration desires
- …