3,270 research outputs found

    The possibilities of developing new industrial markets for farm products

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    Assessing uncertainty in sighting records: an example of the Barbary lion

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    As species become rare and approach extinction, purported sightings can be controversial, especially when scarce management resources are at stake. We consider the probability that each individual sighting of a series is valid. Obtaining these probabilities requires a strict framework to ensure that they are as accurately representative as possible. We used a process, which has proven to provide accurate estimates from a group of experts, to obtain probabilities for the validation of 32 sightings of the Barbary lion. We consider the scenario where experts are simply asked whether a sighting was valid, as well as asking them to score the sighting based on distinguishablity, observer competence, and verifiability. We find that asking experts to provide scores for these three aspects resulted in each sighting being considered more individually, meaning that this new questioning method provides very different estimated probabilities that a sighting is valid, which greatly affects the outcome from an extinction model. We consider linear opinion pooling and logarithm opinion pooling to combine the three scores, and also to combine opinions on each sighting. We find the two methods produce similar outcomes, allowing the user to focus on chosen features of each method, such as satisfying the marginalisation property or being externally Bayesian

    Localization of Control Synthesis Problem for Large-Scale Interconnected System Using IQC and Dissipativity Theories

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    The synthesis problem for the compositional performance certification of interconnected systems is considered. A fairly unified description of control synthesis problem is given using integral quadratic constraints (IQC) and dissipativity. Starting with a given large-scale interconnected system and a global performance objective, an optimization problem is formulated to search for admissible dissipativity properties of each subsystems. Local control laws are then synthesized to certify the relevant dissipativity properties. Moreover, the term localization is introduced to describe a finite collection of syntheses problems, for the local subsystems, which are a feasibility certificate for the global synthesis problem. Consequently, the problem of localizing the global problem to a smaller collection of disjointed sets of subsystems, called groups, is considered. This works looks promising as another way of looking at decentralized control and also as a way of doing performance specifications for components in a large-scale system

    ECONOMIC IMPACTS OF INTERNATIONAL AGRICULTURAL RESEARCH: CASE OF US-EGYPT-IRRI COLLABORATIVE PROJECT ON THE GENERATION OF NEW RICE TECHNOLOGIES

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    Agricultural research managers and scientists are under increasing pressure to demonstrate the efficient and socially-effective use of funds spent on agricultural R&D. These pressures stem from heightened expectations of transparency and accountability in the use of public funds, as well as from the growing demand for evidence of impact on target social groups and environmental services. Finally, advances in agricultural biotechnology research and the ensuing dialogue about the desirability of using biotechnology tools for increasing food production in developing countries have highlighted the need to assess the impacts of international agricultural research in the US, the developing countries, and the international agricultural research centers (IARCs). The US-Egypt ATUT project, funding involves collaborative research among plant breeders, molecular geneticists, and other agricultural scientists in the US, Egypt and IRRI. ATUT rice research accelerated the utilization of three methods for improving the speed and reliability of the screening and evaluation process for identifying salt resistant varieties: shuttle breeding, anther culture and marker-assisted selection. ATUT initiated the application of Marker Assisted Selection (MAS) technology for screening Egyptian rice germplasm. Other ATUT rice technologies in the pipeline have various levels of AATUTness in their research and development. Some of the varieties to be released starting 2003 such as short duration HYVs, will have benefitted less directly from ATUT funding and scientific collaboration. Others- such as hybrid rice varieties will have been very significantly shaped by ATUT. The DREAM model under IFPRI's Global and Regional Program on Agricultural Science and Technology Policy, is used to assess the potential economic benefit of technology outputs for rice, under a range of likely adoption, market and trade scenarios. The simulation model, based on economic surplus theory, uses data and parameters from interviews with scientists, policy makers on the impact and adoption of technology. For this study, ex-ante simulations of the most likely range of outcomes with and without the innovations from ATUT investments. Analyzing the impact of technical change (a simulation over a specified number of years) has provided year-by year estimates of changes in: prices, quantities produced, consumed and traded, levels of adoption, economic benefits to consumers, economic benefits to adopters or losses (non-adopters) to producers. For US and IRRI benefits: Enhanced germplasm pool, stock of knowledge and facilities, and better informed scientists. US scientists in California and Arkansas benefit More integrated into the international rice research community. Gross benefits are estimated for governorates, by producers and consumers, by saline and normal soils, for 1997 to 2017 (end of GoE's current strategic horizon) discounted to 1997 US$. Producers in normal soils derive higher benefits than those in saline soils, some governorates reap more of the producer benefits than others; rural consumers benefit more than urban consumers. Consumer benefits are also estimated for importers of Egyptian rice such as Turkey, Sudan and aggregated Arabian countries. Cost of rice R&D and technology transfer will be measured to derive the IRR and B/C ratios.Research and Development/Tech Change/Emerging Technologies,

    A hybrid information approach to predict corporate credit risk

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    This article proposes a hybrid information approach to predict corporate credit risk. In contrast to the previous literature that debates which credit risk model is the best, we pool information from a diverse set of structural and reduced-form models to produce a model combination based credit risk prediction. Compared with each single model, the pooled strategies yield consistently lower average risk prediction errors over time. We also find that while the reduced-form models contribute more in the pooled strategies for speculative grade names and longer maturities, the structural models have higher weights for shorter maturities and investment grade names
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