75,284 research outputs found
Tables of nuclear cross sections for galactic cosmic rays: Absorption cross sections
A simple but comprehensive theory of nuclear reactions is presented. Extensive tables of nucleon, deuteron, and heavy-ion absorption cross sections over a broad range of energies are generated for use in cosmic ray shielding studies. Numerous comparisons of the calculated values with available experimental data show agreement to within 3 percent for energies above 80 MeV/nucleon and within approximately 10 percent for energies as low as 30 MeV/nucleon. These tables represent the culmination of the development of the absorption cross section formalism and supersede the preliminary absorption cross sections published previously in NASA TN D-8107, NASA TP-2138, and NASA TM-84636
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Ways of seeing evaluation
Copyright @ 2011 Brunel UniversityThis report summarises the evaluation of Ways of Seeing, a community arts project funded by the Heritage Lottery Fund and hosted by the Lightbox, Woking, Surrey from 2008-11. The people involved have had remarkable experiences, choosing how to take part in each stage of preparations for a major public art exhibition. All those involved had disabilities, primarily arising from mental health issues but also including physical disabilities. The project was skilfully designed and led to enable them to make a significant contribution, enhancing their well-being and resulting in the Ways of Seeing exhibition which was widely appreciated. The Lightbox is an award-winning museum, housing a permanent local history exhibition as well as touring major art exhibitions. The Ingram Modern Art collection is on permanent loan, with regular exhibitions of work from the collection. Since the Lightbox opened in 2007, it has had a stated intention to promote local community involvement, successfully obtaining external funding to support this work. Ways of Seeing was the most ambitious project to date, aiming to exhibit selected work from the Ingram Collection alongside art created as part of the project by local disabled people. The emphasis on ways of seeing reflected an interest in their diverse perspectives, especially in relation to long term mental health problems. A steering group was set up, with members from local mental health initiatives and an evaluation team from Brunel University. The project started by orientating participants to how art is created and exhibited, with a series of visits and workshops on major art collections and artistsâ studios. This stage successfully attracted a range of people and was followed by taster workshops of different art techniques. Then participants examined every item in the Ingram Collection and agreed a selection to inspire their own artistic responses. All-day workshops were convened, covering the same techniques as before and giving everyone space and time to get started. Curation of the exhibition gathered pace as final selections were made from participantsâ art works and the Ingram Collection. The exhibition offered opportunities for everyone to have selections of their work exhibited to the public alongside the selected work from the Ingram Collection. A video artist captured the project in film and an MSc occupational therapy student from Brunel University undertook independent interviews of participants. It is clear that this multi-stage and carefully considered approach was highly successful in engaging people who are often excluded from arts events and venues. It was also successful in engaging the public in an innovative and thought-provoking exhibition, challenging assumptions about mental health and promoting the benefits of participation. The willingness of the Lightbox to host and support the project was essential. Based on tolerance, respect and a sympathetic curiosity, with clear and skilled leadership, the project enabled participants to make significant changes in their own lives.This study was funded by the Heritage Lottery Fund
Dynamic Changes in Market Structure and Competition in the Corn and Soybean Seed Sector
The purpose of this paper is to analyze the dynamics of R&D investments, and the structure of the seed distribution sector using novel data sets that have not been used before to describe competition in these industries. The results describe four sets of issues of particular importance. One is that while all agbiotechology firms have increased their R&D expenditures, there have been sharp differences in the scope of this spending. Most important is that this has spawned the growth in what is now referred as âseeds and traits.â Second, a large number of future traits will be commercialized in the coming years. A third set of results indicates that one firm grew its market share by 14% and a portion of this growth has been through acquisition. The other three majors lost market share, but the ISC (independent seed companies) grew by 10%. At the crop reporting district level, the industry concentration ratios for the four largest firms (CR4) in most regions are .5â.7. Finally, farmers purchased corn and soybean seed from 4â7 different companies in most crop reporting districts (CRD) and up to 20 or more companies in the larger producing regions.Agbiotechnology, grain seeds, competition, Agribusiness, Crop Production/Industries, Demand and Price Analysis,
MARKETING OF WHEAT ON A CONSTANT AND NIL MOISTURE BASIS
This study examined moisture specification practices in the United States and for major exporters and assessed impacts of changes to a nil or constant moisture basis on prices and revenue. These were examined under scenarios where information on moisture in current prices is limited and under a scenario where current prices reflect Full Knowledge of moisture advantages. Results indicate that changing to a nil moisture basis (which requires a subsequent adjustment in volumes to reflect the subtraction of moisture) would increase reported prices from 42 to 70 c/bu for the wheat classes, while changing to a 12 percent constant moisture basis would have limited impacts on reported prices. Effects on relative prices/revenue depend on whether knowledge of moisture advantages are reflected in current prices. If current prices reflect moisture advantages (Full Knowledge), then relative effects on prices/revenues are minimal. If current prices do not reflect moisture advantages (Limited Knowledge), then prices/revenue in drier production regions would increase.moisture, specifications, pricing, wheat, constant moisture, nil moisture, Crop Production/Industries,
PROCUREMENT RISKS AND STRATEGIES TO IMPROVE QUALITY CONSISTENCY IN WHEAT SHIPMENTS
Consistency of functional characteristics in wheat is a concern confronting buyers and sellers. This research analyzes the cost and risk of different procurement strategies for importers. A stochastic simulation model is used to determine the probability of a functional characteristic being satisfied subject to quality targets and costs for alternative purchase strategies (purchase by protein only, variety, location, variety by location, or functional tests). Joint probabilities of meeting specifications and costs were determined for the alternative purchase strategies. Stochastic dominance was used to determine which purchase strategies dominate others, and stochastic efficiency was utilized to determine the degree of preference. Results indicate that, as more specific characteristics are incorporated into a contract, the probabilities of meeting end-use requirements increase. Requirements of specific characteristics come with a higher cost, due to increased testing costs related to identity preservation. Risk premiums for alternative strategies were derived.Buying Strategies, Location, Variety, Functional Characteristic Tests, Costs, Risks, Simulation, Stochastic Dominance, Crop Production/Industries, Risk and Uncertainty,
CONSISTENCY OF QUALITY CHARACTERISTICS IN HARD RED SPRING WHEATS
Greater sophistication of buyers in the wheat market has increased demands for higher quality wheats and focused attention on the consistency of the quality of wheat purchased. In this study, the variability of wheat quality characteristics was examined at different stages of the marketing chain. Variability was measured by variety and at farm and export levels. Comparisons were made with Canada where similar data were available. Different measures of variability were utilized where data were available. Inter-year variability, intra-year variability, and within-lot variability of wheat quality characteristics were measured at different points in the wheat marketing chain in the United States and Canada. Variability of many characteristics was similar between Canada and the United States for changes in annual average levels between years and for within year variability. In both Canada and the United States, higher grades exhibited lower variability than lower grades. In addition, the within-year variability of protein and dockage declined from farm level to export levels for the United States. The variability of average levels for grade and protein segregations between sampling periods in Canada was similar at both the farm production and export levels.Quality, Consistency, Quality Variability, Wheat Export Quality, Farm Production Quality, Wheat Variety Quality, Canada, United States, Production Economics,
Grain Pricing and Transportation: Dynamics and Changes in Markets
Agricultural Finance, Crop Production/Industries, Marketing,
COOPERATIVE MARKETING IN SPECIALTY GRAINS AND IDENTITY PRESERVED GRAIN MARKETS
Marketing of specialty and identity preserved grains has become an important strategy in the grain marketing industry and is being driven, in part, by consumer and processor demand and an interest in non-GM products. This study provides background and practices of numerous organizations involved in marketing of specialty/identity preserved grains. Supporting marketing activities are reviewed. Key factors in the success (or failure) of their efforts are identified. Major challenges facing the participants in the specialty/IP grain marketing industry are discussed. The primary focus is on the role of agricultural cooperatives and producer owned alliances.identity preservation, IP, segregation, traceability, specialty products, genetically modified, GM, non-GM, cooperative, alliance., Agribusiness,
EFFECT OF HARD RED SPRING WHEAT CONSISTENCY ON MILLING VALUE
Increased concerns over the quality of wheat in domestic and export markets has focused attention on the consistency of wheat quality. This study utilized three measures to examine the effect of variability in characteristics on the milling value of wheat. Distributions and correlations for wheat quality characteristics were estimated from U.S. wheat export data from 1985-1997. Effects of variability of wheat characteristics on the value of wheat to the miller for each of the three measures were estimated using a simulation model. U.S. No. 1 exports of Hard Red Spring (HRS) had higher value to millers on each of the three measures (net wheat, millable wheat index, and value added in milling) than did exports of No. 2 or better (OB). However, the value to millers of No. 1 HRS was more variable than for No. 2 OB HRS, likely due to a larger negative correlation between the levels of moisture and shrunken and broken kernels in exports of No. 2 OB HRS than No. 1 HRS. Further, the value of wheat to millers for each of the three measures varied substantially by importing country. Sensitivity analysis indicated that increases in the consistency of moisture would provide the greatest reduction in the variability of value to millers, while increases in the consistency of foreign material, shrunken and broken kernels, and dockage had lesser impacts. This suggests that millers looking to increase the value of wheat lots used in milling may want to consider adding restrictions/incentives on moisture to limit the variability from lot to lot. However for dockage, shrunken and broken kernels, and foreign material, the focus should be on actual levels within lots rather than variability between lots.quality consistency, wheat, net wheat, millable wheat value index, milling value, HRS, HRW, Marketing,
RECIPROCAL ACCESS IN U.S./CANADIAN GRAIN TRADE: BACKGROUND ISSUES FOR THE U.S. GRAIN TRADE
The purpose of this paper is to review past trade relations in the grains sector between the United States and Canada and to document trade barriers and the potential for the evolution of reciprocal trade. Historical trade flows between the United States and Canada in the grains sector are reviewed. Terms of recent trade agreements and other trade restrictions are described. Then, some of the important differences in the marketing system are described and compared as well as changes in the Canadian grain marketing system. Finally, the concept of reciprocal access is developed in the context of the evolving trading relations between these two countries.grain trade, U.S.-Canada trade, trade policy, International Relations/Trade,
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