The resupply interface mechanism RMS compatibility test

Spacecraft on-orbit servicing consists of exchanging components such as payloads, orbital replacement units (ORUs), and consumables. To accomplish the exchange of consumables, the receiving vehicle must mate to the supplier vehicle. Mating can be accomplished by a variety of docking procedures. However, these docking schemes are mission dependent and can vary from shuttle bay berthing to autonomous rendezvous and docking. Satisfying the many docking conditions will require use of an innovative docking device. The device must provide fluid, electrical, pneumatic and data transfer between vehicles. Also, the proper stiffness must be obtained and sustained between the vehicles. A device to accomplish this, the resupply interface mechanism (RIM), was developed. The RIM is a unique device because it grasps the mating vehicle, draws the two vehicles together, simultaneously mates all connectors, and rigidizes the mating devices. The NASA-Johnson Manipulator Development Facility was used to study how compatible the RIM is to on orbit docking and berthing. The facility contains a shuttle cargo bay mockup with a remote manipulator system (RMS). This RMS is used to prepare crew members for shuttle missions involving spacecraft berthing operations. The MDF proved to be an excellant system for testing the RIM/RMS compatibility. The elements examined during the RIM JSC test were: RIM gross and fine alignment; berthing method sequence; visual cuing aids; utility connections; and RIM overall performance. The results showed that the RIM is a good device for spacecraft berthing operations. Mating was accomplished during every test run and all test operators (crew members) felt that the RIM is an effective device. The purpose of the JSC RIM test and its results are discussed

Assessing Demographic Changes and Income Inequalities: A Case Study of West Virginia

This study investigates demographic change and income inequalities, and relationship between economic growth and income inequality in West Virginia. Income growth was positively related with population and employment growth, but is significantly and negatively related with income inequality. This indicates that higher income inequality is associated with slower economic growth.Labor and Human Capital,

Finding the Pion in the Chiral Random Matrix Vacuum

The existence of a Goldstone boson is demonstrated in chiral random matrix theory. After determining the effective coupling and calculating the scalar and pseudoscalar propagators, a random phase approximation summation reveals the massless pion and massive sigma modes expected whenever chiral symmetry is spontaneously broken.Comment: 3 pages, 1 figure, revte

THE ROLE OF SMALL BUSINESS IN ECONOMIC GROWTH AND POVERTY ALLEVIATION IN WEST VIRGINIA: AN EMPIRICAL ANALYSIS

In OLS and 2SLS regression analysis a positive relationship exists between small business and economic growth. A strong inverse relationship also exists between the incidence of poverty and small business and economic growth. Thus, the empirical result establishes the linkage between small business, economic growth and the incidence of povertyResearch Methods/ Statistical Methods,

Optical alignment system Patent

Electro-optical/computer system for aligning large structural members and maintaining correct positio

Is Income Inequality Endogenous in Regional Growth?

This study focuses on testing the relationship between income inequality and growth within U.S. counties, and the channels through which such effects are observed. The study tests three hypotheses: (1) income inequality has an inverse relationship with growth; (2) regional growth adjustments are the channels through which the inequality and growth are equilibrated; and (3) income inequality is endogenous to regional growth and its adjustment. Results, based on a system of equations estimation, confirm the hypotheses that income inequality has a growth dampening effect; income inequality is endogenous to regional growth and growth adjustment; and the channels through which income inequality determines growth are regional growth adjustments, such as migration and regional adjustment in job and income growth. Results have numerous policy implications: (1) to the extent that income inequality is endogenous, its equilibrium level can be internally determined within a regional growth process; (2) to the extent that traditional income inequality mitigating policies have indirect effect on overall regional growth, they may have unintended indirect effects on income inequality; and (3) to the extent that regional growth adjustment also equilibrates income inequality, such forces can be utilized as policy instruments to mitigate income inequality, and its growth dampening effects hence forth.Income inequality, economic growth, Gini coefficient, growth modeling, population change, per capita income, Community/Rural/Urban Development, Public Economics, I32, J15, O18, P25, R11, R23, R25, R51, R53, R58,

Transport composite fuselage technology: Impact dynamics and acoustic transmission

A program was performed to develop and demonstrate the impact dynamics and acoustic transmission technology for a composite fuselage which meets the design requirements of a 1990 large transport aircraft without substantial weight and cost penalties. The program developed the analytical methodology for the prediction of acoustic transmission behavior of advanced composite stiffened shell structures. The methodology predicted that the interior noise level in a composite fuselage due to turbulent boundary layer will be less than in a comparable aluminum fuselage. The verification of these analyses will be performed by NASA Langley Research Center using a composite fuselage shell fabricated by filament winding. The program also developed analytical methodology for the prediction of the impact dynamics behavior of lower fuselage structure constructed with composite materials. Development tests were performed to demonstrate that the composite structure designed to the same operating load requirement can have at least the same energy absorption capability as aluminum structure

Self-assembled ErAs islands in GaAs for optical-heterodyne THz generation

We report photomixer devices fabricated on a material consisting of self-assembled ErAs islands in GaAs, which is grown by molecular beam epitaxy. The devices perform comparably and provide an alternative to those made from low-temperature-grown GaAs. The photomixer's frequency response demonstrates that the material is a photoconductor with subpicosecond response time, in agreement with time-resolved differential reflectance measurements. The material also provides the other needed properties such as high photocarrier mobility and high breakdown field, which exceeds 2×10^5 V/cm. The maximum output power before device failure at frequencies of 1 THz was of order 0.1 µW. This material has the potential to allow engineering of key photomixer properties such as the response time and dark resistance

Imaging X-ray spectrometer

An X-ray spectrometer for providing imaging and energy resolution of an X-ray source is described. This spectrometer is comprised of a thick silicon wafer having an embedded matrix or grid of aluminum completely through the wafer fabricated, for example, by thermal migration. The aluminum matrix defines the walls of a rectangular array of silicon X-ray detector cells or pixels. A thermally diffused aluminum electrode is also formed centrally through each of the silicon cells with biasing means being connected to the aluminum cell walls and causes lateral charge carrier depletion between the cell walls so that incident X-ray energy causes a photoelectric reaction within the silicon producing collectible charge carriers in the form of electrons which are collected and used for imaging