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Method of circuit development separates electrical functions into noninterdependent parts, uses standard, commercially available circuit elements, and establishes unified circuit-packaging arrangement. Packaging scheme is cost-effective, does not compromise electrical circuit performance from video to UHF frequencies, and leaves circuits accessible for modification and adjustment.
A graphite radiant heating array, capable of heating a 5-ft span of shuttle wing leading edge or a 4 x 8 ft flat panel through an entry thermal profile up to 3200 G, has been designed and built by McDonnell Douglas Corporation for NASA-Johnson Space Center. The unique, interchangeable, self-contained heather modules and their versatile support structure/coolant manifold are discussed along with the extensive thermal analysis that accompanied the design effort. A complete description of the geometric capabilities of the array, as well as the design details of the individual modules, is presented. The complete performance envelope of the array is discussed, including maximum temperature and gradients, heating uniformity, and the required utilities and support equipment.
Operational and peak holding amplifiers are discussed as useful circuits for bioluminescence assays. Circuit diagrams are provided. While analog methods can give a good integration on short time scales, digital methods were found best for long term integration in bioluminescence assays. Power supplies, a general photometer circuit with ratio capability, and variations in the basic photometer design are also considered.
The evaluation indicates the need to establish professional standards for judging the adequacy with which assessments are performed and for analyzing the sufficiency of the definition of task-objectives that are given to or posited by assessment entities. Three basic performance criteria are posited: interpretability, warrantability, and serviceability of utility of assessment outcome to the relevant decisional entity or entities.
The design features of the SUMC-2B computer, also called the IBM-HTC are described. It is general purpose digital computer implemented with flexible hardware elements and microprograming to enable low cost customizing to a wide range of applications. It executes the S/360 standard instruction set to maintain problem state compability. Memory technology, extended instruction sets, and I/O channel variations are among the available options.
Weldless methods and means are described for securing flanges to the projecting ends of an unmachined box beam framework in such a manner that the flanged structure may be reused without modification. And one framework may be readily assembled to another by simply matching the flanges together and passing connecting members between performed holes in the structures.
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Portable, recirculating-water-flow, and temperature-control device is used with solar simulator and actual sunlight to test and evaluate several solar-collector panel coatings, panel designs, and scaled-down collector subsystems. System can be pressurized to prevent boiling and allows operation above 100 degrees Centigrade.
Process involves electroplating multiaperature masks as unit, eliminating alinement and assembly difficulties previously encountered. Technique may be applied to masks in automated and surveillance light systems, when precise, wide angle field of view is needed.
The applicability of CAMAC and NIM to various payloads was studied. A major result is summarized in tabular form showing the applicability of standard available CAMAC and NIM modules to the six experimental payloads chosen. It was concluded that CAMAC has wide applicability within the experiments considered.
Features basic to the integrated utility system, such as solid waste incineration, heat recovery and usage, and water recycling/treatment, are compared in terms of cost, fuel conservation, and efficiency to conventional utility systems in the same mean-climatic area of Washington, D. C. The larger of the two apartment complexes selected for the test showed the more favorable results in the three areas of comparison. Restrictions concerning the sole use of currently available technology are hypothetically removed to consider the introduction and possible advantages of certain advanced techniques in an integrated utility system; recommendations are made and costs are estimated for each type of system.
A family of mercury ion thruster modules has been developed which extends the basic design of the Hughes-developed 1-mlb Engineering Model Thruster to accommodate the extended thrust range from 0.5 mlb to 4 mlb. In the subject program, separate Discharge Chamber Modules (DCM's) have been optimized for operation at nominal thrust levels T = 0.5 mlb and 2 mlb; DCM optimization is continuing at thrust level T = 4 mlb. Performance optimization required modification of the beam-extraction system and of discharge-chamber components; however, the cathodes and mechanical structure are unchanged from the Engineering Model design. Performance data on the optimized modules are given.
The advent of the Shuttle launch vehicle and Spacelab have resulted in adequate weight and volume such that experiment electronics can be implemented at relatively low cost using spaceflight versions of CAMAC and NIM modules. Studies of 10 modules by manufacturers have shown that power reduction overall by a factor of about 3 can be accomplished. This is adequate both from the point of view of consumption and temperature rise in vacuum. Our studies have shown that a stock of about 45 module types is required and a listing is given. The changes required in these modules in order to produce spaceflight versions are described. And finally, the further studies, prototyping and testing leading to eventual flight qualification are described.
In the study described, a scanning dual-channel cross-beam laser Doppler velocimeter (developed for measuring simultaneously the two orthogonal components of flow velocity and turbulence intensity) was used to measure the instantaneous velocity characteristics of a model helicopter rotor and in a vortex wake survey experiment on a Boeing 747 aircraft model. Particular attention is given to a special purpose dual-loop frequency tracker developed to track and demodulate 10 microsecond wide pulse burst Doppler signals with a study cycle of 25% (or narrower signals at a higher duty cycle) generated by the laser Doppler velocimeter.
The paper presents the technical feasibility of generating electricity by using a gas turbine in conjunction with a paraboloid of revolution (dish) solar concentrator. A conceptual design of a dish concentrator is obtained by parametrically examining the significant optical parameters. The optical performance analysis was conducted using a Monte Carlo ray-trace simulation program. The performance of four candidate thermodynamic cycles utilizing two working fluids was analyzed; the cycles were the regenerative and nonregenerative Brayton cycles of both open and closed type. Air and helium were the working fluids for the open and closed type respectively. Heat transfer from the solar radiation to the gas flowing in metal tubes at the receiver was also analyzed. A paraboloid of revolution dish with a cavity receiver using an open air regenerative Brayton cycle turbine emerged as a technically feasible concept in the power range from 30 to 100 KWth per module.
Heat-Pipe panel assembled by joining series of Heat-Pipe modules is presented. Each module is identical and includes own radiator Fin and Fluid-Header section. Arrangement gives high turn-down ratio permitting ammonia heat pipes to freeze under low conditions.
Chassis-mounted module makes it easy to remove and attach ground wires. With module, more ground connections are made in smaller area and no terminal lugs, lockwashers, or locknuts are required. Device also reduces holes that are punched or drilled in chassis for ground connections.
The fundamentals of a computer program, simulated monochromatic atmospheric radiative transfer (SMART), which calculates atmospheric path transmission, solar radiation, and thermal radiation in the 4.6 micrometer spectral region, are described. A brief outline of atmospheric absorption properties and line by line transmission calculations is explained in conjunction with an outline of the SMART computational procedures. Program flexibility is demonstrated by simulating the response of a gas filter correlation radiometer as one example of an atmospheric infrared sensor. Program limitations, input data requirements, program listing, and comparison of SMART transmission calculations are presented.