22,744 research outputs found
Technique for measuring absorptance and emittance by using cyclic incident radiation
Cyclic radiation technique has been developed for determining absorptance and emittance of metal surfaces. Using this technique both absorptance and emittance can be determined from one set of data, and variable and controlled temperature levels are possible
Aerial thermography for energy conservation
Thermal infrared scanning from an aircraft is a convenient and commercially available means for determining relative rates of energy loss from building roofs. The need to conserve energy as fuel costs makes the mass survey capability of aerial thermography an attractive adjunct to community energy awareness programs. Background information on principles of aerial thermography is presented. Thermal infrared scanning systems, flight and environmental requirements for data acquisition, preparation of thermographs for display, major users and suppliers of thermography, and suggested specifications for obtaining aerial scanning services were reviewed
Earth science information: Planning for the integration and use of global change information
The Consortium for International Earth Science Information Network (CIESIN) was founded in 1989 as a non-profit corporation dedicated to facilitating access to, use and understanding of global change information worldwide. The Consortium was created to cooperate and coordinate with organizations and researchers throughout the global change community to further access the most advanced technology, the latest scientific research, and the best information available for critical environmental decision making. CIESIN study efforts are guided by Congressional mandates to 'convene key present and potential users to assess the need for investment in integration of earth science information,' to 'outline the desirable pattern of interaction with the scientific and policy community,' and to 'develop recommendations and draft plans to achieve the appropriate level of effort in the use of earth science data for research and public policy purposes.' In addition, CIESIN is tasked by NASA to develop a data center that would extend the benefits of Earth Observing System (EOS) to the users of global change information related to human dimensions issues. For FY 1991, CIESIN focused on two main objectives. The first addressed the identification of information needs of global change research and non-research user groups worldwide. The second focused on an evaluation of the most efficient mechanisms for making this information available in usable forms
Real-Time Planning with Primitives for Dynamic Walking over Uneven Terrain
We present an algorithm for receding-horizon motion planning using a finite
family of motion primitives for underactuated dynamic walking over uneven
terrain. The motion primitives are defined as virtual holonomic constraints,
and the special structure of underactuated mechanical systems operating subject
to virtual constraints is used to construct closed-form solutions and a special
binary search tree that dramatically speed up motion planning. We propose a
greedy depth-first search and discuss improvement using energy-based
heuristics. The resulting algorithm can plan several footsteps ahead in a
fraction of a second for both the compass-gait walker and a planar
7-Degree-of-freedom/five-link walker.Comment: Conference submissio
Ultra-violet Finiteness in Noncommutative Supersymmetric Theories
We consider the ultra-violet divergence structure of general noncommutative
supersymmetric gauge theories, and seek theories which are all-orders
finite.Comment: 11 pages, Tex, one figure. Uses harvmac (big) and eps
Enterprise Risk Management In The Oil And Gas Industry: An Analysis Of Selected Fortune 500 Oil And Gas Companies Reaction In 2009 And 2010
In 2009, four of the top ten Fortune 500 companies were classified within the oil and gas industry. Organizations of this size typically have an advanced Enterprise Risk Management system in place to mitigate risk and to achieve their corporations\u27 objectives. The companies and the article utilize the Enterprise Risk Management Integrated Framework developed by the Committee of Sponsoring Organizations (COSO) as a guide to organize their risk management and reporting. The authors used the framework to analyze reporting years 2009 and 2010 for Fortune 500 oil and gas companies. After gathering and examining information from 2009 and 2010 annual reports, 10-K filings, and proxy statements, the article examines how the selected companies are implementing requirements identified in the previously mentioned publications.
Each section examines the companies Enterprise Risk Management system, risk appetite, and any other notable information regarding risk management. One observation was the existence or non-existence of a Chief Risk Officer or other Senior Level Manager in charge of risk management. Other observations included identified risks, such as changes in economic, regulatory, and political environments in the different countries where the corporations do business. Still others identify risks, such as increases in certain costs that exceed natural inflation, volatility and instability of market conditions. Fortune 500 oil and gas companies included in this analysis are ExxonMobil, Chevron, ConocoPhillips, Baker Hughes, Valero Energy, and Frontier Oil Corporation.
An analysis revealed a sophisticated understanding and reporting of many types of risks, including those associated with increasing production capacity. Specific risks identified by companies included start-up timing, operational outages, weather events, regulatory changes, geo-political and cyber security risks, among others. Mitigation efforts included portfolio management and financial strength. There is evidence that companies in later reports (2013) are more comprehensive in their risk management and reports as evidenced by their 10-K and Proxy Statements (Marathon Oil Corporation, 2013)
Fayet-Iliopoulos D-terms and anomaly mediated supersymmetry breaking
We show that in a minimal extension of the MSSM by means of an extra U(1)
gauge group, the negative mass-squared problem characteristic of the Anomaly
Mediated Supersymmetry Breaking scenario is naturally solved by means of
Fayet-Iliopoulos D-terms. We derive a set of sum rules for the sparticle masses
which are consequences of the resulting framework.Comment: 11 pages, including 1 figure. Plain TeX. Uses Harvmac and epsf. Final
version to appear in Phys. Lett. B; some minor improvement
Electro-thermal rocket Patent
Electrothermal rocket engine using resistance heated heat exchange
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