Communications technology satellite: United States experiments and disaster communications applications

Ground antennas from 0.6 to 5.0 meters in diameter were used as remote earth terminals by the United States for both wideband (television) and narrowband (voice, data) communication in conjunction with the Canadian Hermes satellite's high power transmitter. Experiments summarized cover teleconferencing and duplex videoconferencing for medical, educational, and civic purposes, as well as the remote interpretation of multilingual broadcasts from the United Nations. The capabilities of the system during real and simulated disasters at airports are assessed. Particular attention is given to miniexperiments for flood control in the Mississippi River basin and in Johnstown, Pennsylvania during the 1977 flood

Development of Cellulose Acetate-Based Scaffold for Bone Tissue Engineering Applications

Cellulose Acetate (CA) based biomaterials are being used as substrates for bone ingrowth applications due to their nontoxic and nonirritant nature coupled with optimum morphology and stiffness. Electrospinning with additives and/or post-treatment has emerged as a viable protocol to further improve mechanical properties of CA and expand its utility. Herein, we highlight the role of potassium chloride (KCl) in association with airdrying to enhance the elastic modulus and tensile strengths of CA fibers. Salt aggregation in between fibers is observed through Scanning Electron Microscopy (SEM), however, Fourier-transform infrared (FTIR) analysis signifies the interactions between K+ ions and acetyl groups. The increase in KCl concentration (2 to 4 to 6%) boosts the elastic modulus to 176 MPa (52 times than pure CA) and tensile strength to 1.2 MPa (9 times than pure CA). The presence of K+ ions, indeed, offers osteoconduction to fibers and thus the outcome has potential in bone tissue engineering applications

Second-order small-disturbance solutions for hypersonic flow over power-law bodies

Similarity solutions were found which give the adiabatic flow of an ideal gas about two-dimensional and axisymmetric power-law bodies at infinite Mach number to second order in the body slenderness parameter. The flow variables were expressed as a sum of zero-order and perturbation similarity functions for which the axial variations in the flow equations separated out. The resulting similarity equations were integrated numerically. The solutions, which are universal functions, are presented in graphic and tabular form. To avoid a singularity in the calculations, the results are limited to body power-law exponents greater than about 0.85 for the two-dimensional case and 0.75 for the axisymmetric case. Because of the entropy layer induced by the nose bluntness (for power-law bodies other than cones and wedges), only the pressure function is valid at the body surface. The similarity results give excellent agreement with the exact solutions for inviscid flow over wedges and cones having half-angles up to about 20 deg. They give good agreement with experimental shock-wave shapes and surface-pressure distributions for 3/4-power axisymmetric bodies, considering that Mach number and boundary-layer displacement effects are not included in the theory

Nuclear Thermal Rocket/Vehicle Design Options for Future NASA Missions to the Moon and Mars

The nuclear thermal rocket (NTR) provides a unique propulsion capability to planners/designers of future human exploration missions to the Moon and Mars. In addition to its high specific impulse (approximately 850-1000 s) and engine thrust-to-weight ratio (approximately 3-10), the NTR can also be configured as a 'dual mode' system capable of generating electrical power for spacecraft environmental systems, communications, and enhanced stage operations (e.g., refrigeration for long-term liquid hydrogen storage). At present the Nuclear Propulsion Office (NPO) is examining a variety of mission applications for the NTR ranging from an expendable, single-burn, trans-lunar injection (TLI) stage for NASA's First Lunar Outpost (FLO) mission to all propulsive, multiburn, NTR-powered spacecraft supporting a 'split cargo-piloted sprint' Mars mission architecture. Each application results in a particular set of requirements in areas such as the number of engines and their respective thrust levels, restart capability, fuel operating temperature and lifetime, cryofluid storage, and stage size. Two solid core NTR concepts are examined -- one based on NERVA (Nuclear Engine for Rocket Vehicle Application) derivative reactor (NDR) technology, and a second concept which utilizes a ternary carbide 'twisted ribbon' fuel form developed by the Commonwealth of Independent States (CIS). The NDR and CIS concepts have an established technology database involving significant nuclear testing at or near representative operating conditions. Integrated systems and mission studies indicate that clusters of two to four 15 to 25 klbf NDR or CIS engines are sufficient for most of the lunar and Mars mission scenarios currently under consideration. This paper provides descriptions and performance characteristics for the NDR and CIS concepts, summarizes NASA's First Lunar Outpost and Mars mission scenarios, and describes characteristics for representative cargo and piloted vehicles compatible with a reference 240 t-class heavy lift launch vehicle (HLLV) and smaller 120 t HLLV option. Attractive performance characteristics and high-leverage technologies associated with both the engine and stage are identified, and supporting parametric sensitivity data is provided. The potential for commonality of engine and stage components to satisfy a broad range of lunar and Mars missions is also discussed

Prospectus, August 26, 1985

https://spark.parkland.edu/prospectus_1985/1015/thumbnail.jp

Visións competitivas de conectividade no contexto da Iniciativa Belt and Road : o desenvolvemento de infraestructuras en Indonesia

Traballo de Fin de Grao en EconomíaAs necesidades globais de investimento en infraestructuras corren o risco de quedar sen ser materializadas. Asia é unha das rexións cun maior déficit de infraestructuras. As necesidades de cada país son diferentes, así como o seu modelo de desenvolvemento. Nese contexto, Belt and Road Initiative (BRI) foi anunciada polo presidente chinés Xi Jinping no ano 2013, coa idea de conseguir unha maior integración rexional e conectar o supercontinente Euroasiático. China, polo tanto, presentou un novo modelo de liderazgo. A súa vez, os países da rexión seguen os seus propios intereses, servindo ademáis de contrapeso ás intencións chinesas. As diferentes visións e as escollas finais dos diferentes países determinarán se finalmente as necesidades se financian con investimento público ou privado e o maior multilateralismo ou bilateralismo das relacións económicas e comerciais. Por outro lado, hai unha tendencia dos países receptores a intentar aproveitarse da competencia, e da búsqueda do equilibrio entre colaboración e competición entre os países activos nas propostas. Nese contexto, a cercanía vai ser cada vez máis relevante económica e estratéxicamente. No caso de Indonesia, o país ten unhas necesidades de infraestructuras elevadas. Estáseguindo un modelo cun papel elevado do sector público, que encaixa coa proposta chinesa, pero que mantén os problemas en termos de eficiencia. A nivel internacional, intenta aproveitarse da competencia, especialmente entre Xapón e China, e aumentar as relacións co resto do mundo a nivel comercial

The Multifaceted Nature of Food and Nutrition Insecurity around the World and Foodservice Business

The international concept of food security is a situation where all people have physical, social, and economic access at all times to sufficient, safe, and nutritious food that meets their dietary needs and food preferences for an active and healthy life. All four parameters (availability, access, utilization, and stability) should therefore be measured to determine food security status.Taking into account these premises, this book aims to present original research articles and reviews concerning the following: Agriculture and food security; Agri-tourism and its potential to assist with food security; Business–science cooperation to advance food security; Competing demands and tradeoffs for land and water resources; Consumer behavior, nutritional security and food assistance programs; Food and health; Global and local analyses of food security and its drivers; Global governance and food security; Infectious and non-infectious diseases and food security; Reducing food loss and waste; Reducing risks to food production and distribution from climate change; Supply chains and food security; Technological breakthroughs to help feed the globe; Tourism food security relationship; Urbanization, food value chains, and the sustainable, secure sourcing of food; Food and service quality at food catering establishments; Consumer behavior at foodservice operations (restaurants, cafés, hotels)

Levantamento de reconhecimento de média intensidade dos solos e avaliação da aptidão agrícola das terras em 100.000 hectares da Gleba Machadinho, no Município de Ariquemes, Rondônia.

bitstream/item/62539/1/CNPS-BOL.-PESQ.-16-82.pdf; bitstream/item/216872/1/Mapa-de-Reconhecimento-de-Alta-Intensidade-dos-Solos-de-uma-Area-da-Gleba-Machadinho-no-Municipio-de-Ariquemes-1987.pdf; bitstream/item/216873/1/Mapa-de-Avaliacao-da-Aptidao-Agricola-das-Terras-de-uma-Area-da-Gleba-Machadinho-no-Municipio-de-Ariquemes-1987.pdfAcompanha 2 mapas, p&b. Escala 1:50.000. Contrato firmado entre a EMBRAPA-SNLCS e o INCRA-DRF