8,904 research outputs found
A three-dimensional Gaussian-beam ray-tracing program for designing interferometer/polarimeter plasma diagnostics
We have developed a three-dimensional Gaussian-beam ray-tracing program to aid in the design of infrared, far-infrared, and millimeter waveinterferometer and polarimeterdiagnostic systems for magnetic confinementfusion relevant plasma physicsexperiments. An overview of the program is presented along with a description of the ray-tracing algorithm. A model is developed for the case of diffraction of a Gaussian beam off a cylindrical grating and is shown to be in good agreement with experimental measurements. The program has been used to aid the design of the scanning-grating interferometer system for the H-1NF heliac experimental plasma device. The program is written in the Research Systems Inc. Interactive Data Language and, on a typical modern personal computer, is able to trace and render the ∼50 element three-view 44-beam H-1NF interferometer optical system in about one minute.This work
was in part supported by the Australian Institute of Nuclear
Science and Engineering, the Australian Research Council,
and the Australian Vice-Chancellors’ Committee Commonwealth
Scholarship and Fellowship Plan
Renewable Energy Resources Impact on Clean Electrical Power by developing the North-West England Hydro Resource Model.
This paper describes the development of a sequential decision support system to promote hydroelectric power in North-West England. The system, composed of integrated models, addresses barriers to the installation of hydroelectric power schemes. Information is linked through an economic assessment which identifies different turbine options, assesses their suitability for location and demand; and combines the different types of information in a way that supports decision making. The system is structured into five components: the hydrological resource is modelled using Low Flows 2000, the turbine options are identified from hydrological, environmental and demand requirements; and the consequences of different solutions will be fed into other components so that the environmental impacts and public acceptability can be assessed and valued. A preliminary case study is presented on an old gunpowder works to illustrate how the resource model may be employed. Historical architectural structures, power uptake and educational instruction of hydro power technology are considered
CLIMATE CHANGE IMPACTS ON HYDROLOGICAL PROCESSES IN SILVER BOW CREEK WATERSHED
Climate change is expected to alter temperature and precipitation regimes across the globe and have varying effects on localized hydrological processes. For Silver Bow Creek (SBC), a headwater to the Clark Fork River in western Montana, the magnitude, duration, and frequency of spring runoff and summer base flow are dependent on the processes of snow accumulation and melt. Headwater hydrology and mountain streams will likely experience earlier snowmelt, increased spring flows, and decreased summer flows due to climate change.
A process-based hydrological model the Soil and Water Assessment Tool (SWAT) was used to evaluate the effects of climate change on SBC spring runoff and summer base flows. SWAT is a continuous simulation model that allows the user to predict surface water discharge, sediment loading, and stream nutrient content from user specified meteorological forcing functions. The SBC model was developed using 1/3 arc second DEM, SSURGO soil database, Montana land cover framework, and observed climatic data and was calibrated between the years 2008-2009 and validated between the years 2010-2011 to daily USGS flow data. Projected future downscaled climate change from CMIP5 emission scenarios RCP 2.6, 4.5, 6.0, and 8.5 were used as temperature and precipitation for the modeling period. A calibrated and validated baseline model was used for comparison against the four CMIP5 scenarios. Results were then used to make qualitative inferences about changes in surface water quality due to climate change. Model simulations indicate the timing of spring melt off to be earlier, the duration shorter, and volume to be less than the baseline scenario. One of the limitations to this study was the inability to satisfactorily calibrate and validate daily values
The Impact of Investments in Maize Research and Dissemination in Zambia Part I: Main Report
Michigan State University (MSU) is currently assessing the impact of agricultural research on various commodities in seven African countries: Cameroon (maize, cowpea, sorghum), Kenya (maize, wheat), Malawi (maize), Mali (maize), Niger (sorghum, cowpea, millet), Uganda (oilseeds), and Zambia (maize). These countries were selected because they represent a variety of agro-ecological regions, and because their research systems have received significant levels of funding from USAID. The country studies undertaken by MSU are part of a series of research works recently commissioned to help USAID and the U.S. Congress analyze the effectiveness of aid given to strengthen national agricultural research systems in Africa. In Zambia, MSU collaborated with the Ministry of Agriculture, Food and Fisheries (MAFF) and the University of Zambia's Rural Development Studies Bureau (RDSB) to assess the impact of investments in maize research and dissemination made during the late 1970s and early 1980s. This research resulted in the release of ten new hybrids and open-pollinated varieties between 1984-88. Major support for maize research and dissemination came from the Government of Zambia (GRZ), the Centro Internaciónal de Mejoramiento de Maiz y Trigo (CIMMYT), the Food and Agriculture Organization/United Nations Development Program (FAO/UNDP), the Swedish International Development Authority (SIDA) and the United States Agency for International Development (USAID).food security, food policy, maize, Crop Production/Industries, Research and Development/Tech Change/Emerging Technologies, Downloads July 2008 - June 2009: 19, Q18,
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