An interactive NASTRAN preprocessor

A Langley Research Center version of NASTRAN Level 15.1.0 designed to provide the analyst with an added tool for debugging massive NASTRAN input data is described. The program checks all NASTRAN input data cards and displays on a CRT the graphic representation of the undeformed structure. In addition, the program permits the display and alteration of input data and allows reexecution without physically resubmitting the job. Core requirements on the CDC 6000 computer are approximately 77,000 octal words of central memory

Trajectory-correction propulsion system Patent

Spacecraft trajectory correction propulsion syste

Computer program provides improved longitudinal response analysis for axisymmetric launch vehicles

Computer program calculates axisymmetric launch vehicle steady-state response to axisymmetric sinusoidal loads. A finite element technique is utilized to construct the total launch vehicle stiffness matrix and mass matrix by subdividing the prototype structure into a set of axisymmetric shell components, fluid components, and spring-mass components

Community Response Strategies for Environmental Problems of Water Supply and Wastewater Disposal in Fairbanks, Alaska

This report examines the history of the response strategies of the Fairbanks, Alaska, community to problems of water supply and wastewater disposal. Fairbanks is significant since it is the largest settlement in the northern subarctic and arctic regions of North America. Today, the City of Fairbanks and the surrounding urban area have a combined population of over 40,000

Study of auxiliary propulsion requirements for large space systems. Volume 1: Executive summary

An insight into auxiliary propulsion systems (APS) requirements for large space systems (LSS) launchable by a single shuttle is presented. In an effort to scope the APS requirements for LSS, a set of generic LSSs were defined. For each generic LSS class a specific structural configuration, representative of that most likely to serve the needs of the 1980's and 1990's was defined. The environmental disturbance forces and torques which would be acting on each specific structural configuration in LEO and GEO orbits were then determined. Auxiliary propulsion requirements were determined as a function of: generic class specific configuration, size and openness of structure, orbit, angle of orientation, correction frequency, duty cycle, number and location of thrusters and direction of thrusters and APS/LSS interactions. The results of this analysis were used to define the APS characteristics of: (1) number and distribution of thrusters, (2) thruster modulation, (3) thrust level, (4) mission energy requirements, (5) total APS mass component breakdown, and (6) state of the art adequacy/deficiency

Environmental quality conditions in Fairbanks, Alaska, 1972

Published by The Institute of Water Resources and The Institute of Social, Economic and Government Research Fairbanks, AlaskaThis study represents a starting point for investigating the nature and interconnectivity of environmental quality problems in Fairbanks in the 1970's. Since the Fairbanks flood of 1967, no detailed survey of environmental quality conditions has been conducted despite the impact of the flood, the considerable expansion of the city limits, and the population expansion (anticipated and actual) associated with the oil pipeline. The study focuses on selective aspects of environmental quality of continuing and increasing concern to Fairbanks area residents and also to the city and borough governments. Specifically, the issues analyzed are (1) the environmental setting of the area, (2) structures, especially housing conditions, (3) premise conditions, and (4) waste control. Much of the data was derived from a program called NEEDS, an acronym for Neighborhood Environmental Evaluation and Decision System. NEEDS was developed by the Bureau of Community Environmental Management of the Department of Health, Education, and Welfare for rapid gathering of environmental, health, and social information in urban areas.1 The NEEDS survey design consists of two separate stages. Stage I is concerned with collecting general environmental quality information to determine geographically where the most pronounced environmental health problems exist in a given urban area. Stage II consists of detailed interviews with residents of the identified "problem areas" to determine the exact nature of existing health and environmental problems, e.g., housing, health, availability of services, and attitudes regarding existing government (local, state, and federal) programs. With this information, local officials could begin to reorganize existing programs and/or develop new programs to solve some of the interrelated environmental quality problems in the disadvantaged sections of their cities.The work upon which this report is based was supported by funds provided by the State of Alaska, the University of Alaska at Fairbanks, the United States Public Health Service, and the Office of Water Research and Technology

Apparatus for damping operator induced oscillations of a controlled system

Flight control-related apparatus for damping operator induced oscillations of a controlled system responding to an operator controlled signal is described. The device utilizes a lag-lead filter for frequency and amplitude estimation of the control input, and a rectification and smoothing filter for producing a signal proportional to the absolute value of the frequency and amplitude estimate for use in suppression of the control system output signal. In one embodiment, this is accomplished by computing a correction signal in a correction generating section. In a second embodiment, a second rectification and smoothing filter produces a signal proportional to the absolute value of the controlled input signal. A ratio of the outputs of the first and second rectification and smoothing filters is then used in a generator to generate a gain factor k sub q for the control system to reduce the gain of the output signal of the control system, thereby to provide a damped control output signal without rate limiting the controlled element

The rocket-grenade experiment

Grenade-exploding rocket sonde for measuring temperature and wind up to 90 kilometers altitud

Biology and Fishery for Atlantic Thread Herring, Opisthonema oglinum, along the North Carolina Coast

Thread herrings, Opisthonema spp., are small, nearshore, pelagic clupeid fishes that form dense, surface schools in tropical to subtropical coastal waters. Ecologically, thread herrings form an important forage base for many large, predatory fishes (Finucane and Vaught, 1986). Commercially, thread herrings are targeted by artisanal to moderate-sized seine fisheries off the coasts of Ecuador and Peru (Patterson and Santos, 1992), Costa Rica (Stevenson and Carranza, 1981), Venezuela, the continental margins of the Caribbean, the Gulf of Mexico, and near the islands of Cuba, Hispaniola, Puerto Rico, Jamaica, and Trinidad (Reintjes, 1978). Most of the catch is reduced to fish meal and fish oil (Patterson and Santos, 1992), although minor quantities are used for human consumption (Reintjes, 1978)