Rotary-wing aircraft terrain-following/terrain-avoidance system development

Work being accomplished to develop a real-time, piloted simulation of a helicopter using the vertical motion simulator at NASA Ames is discussed. The trajectory generation algorithm and the flight path controller are described, and the software integration of the entire terrain following/terrain avoidance (TF/TA) system is discussed. Real-time simulation requirements and the unique features of applying TF/TA system to helicopter flight are summarized. Initial results indicate that the system is satisfactory for automatic, low level TF/TA helicopter flight

NEW PROGRAMS TO BENEFIT RURAL HOUSEHOLDS AND BUSINESSES

Consumer/Household Economics,

The Role of Certification in the Brazilian Fruit Chain

Concerns about food safety and standards in the developed countries, particularly in Europe and the United States have made certification inevitable for worldwide fruit producers who target such export markets. The fact that certification is demanded by final consumers is increasingly making buyers, retailers and wholesalers buy certified products from the producers. For the fruit industry in Brazil, certification has important consequences as it ensures access to export markets. Using primary data obtained from interviews with 303 small, medium and large mango and grape producers in the regions of Juazeiro/BA and Petrolina/PE in Brazil, this paper aims at assessing the determinants of demand for certification among mango and grape producers. Empirical analysis using a logit model shows that grapes farmers have higher likelihood for certification than mango growers. The farmer’s education level and years of experience producing fruits are the major positive determinants for certification. The factors which decrease the chances to adopt certification are small size of the farm, nonagricultural income, awareness and trust type of arrangement.Certification, fruits, logit model

Solving a Paradox of Evidential Equivalence

David Builes presents a paradox concerning how confident you should be that any given member of an infinite collection of fair coins landed heads, conditional on the information that they were all flipped and only finitely many of them landed heads. We argue that if you should have any conditional credence at all, it should be 1/2

Impact of certification on fruit producers in the Sao Francisco Valley in Brazil

Producers and exporters of fresh fruits and vegetables from developing countries like Brazil are increasingly required to demonstrate the safety and traceability of their produce up to the consumption stage. In fact, the Brazilian export market is still relatively underdeveloped, with an export share of only 2.4% of the total produced volume. However, certification may also have the effect of a non-tariff trade barrier, undermining the capability and financial ability of especially small-scale farmers in exporting to international markets. This study, therefore, aims at providing an economic analysis of certification on mango and grapes producers. A survey of 303 grapes and mango farmers was conducted in 2006 in the Juazeiro and Petrolina regions of the Sao Francisco Valley in Brazil. Certified and non-certified farmers as well as those in process to obtain certification were included in the sample. Empirical analysis using a logit model shows that grapes farmers have higher probability to certify than mango growers. There are two variables which have a positive and significant effect: education and experience. However, small-scale farms, the dependency on non-agricultural income and a trust-based arrangement have a negative but significant effect.Certification, fruits, logit model

Habitus and Interest in Agroforestry Practices in Missouri

This study analyzes the factors driving interest in two agroforestry practices, riparian buffers and forest farming. Because agroforestry is outside main stream commodity production in US agriculture, the purpose is to evaluate a framework to understand attitudes. The framework incorporates Pierre Bourdieu's notions of "habitus" and "field" along with individual economic and demographic characteristics of farm operators' traditionally used in adoption studies. Four attitudes are analyzed: disengagers, conservatives, lifestyle, and accumulators. A Logit regression measures the effects of respondents' attitudes, and other internal and external factors to assess interest in each practice. The data used is from a household survey of 364 farm-operators from the Fox Wyaconda watershed in northeast Missouri and Scott County in southeast Missouri gathered in 1999. Findings show that a conservative or a lifestyle attitude, are significant, with high probability of being interested in riparian buffers. Those with an accumulator or a lifestyle attitude have a significant and high probability of being interested in forest farming. Other variables also significant in riparian buffer interest are knowledge of agroforestry, and interest in alternative farming practices, and especially having perceptions of erosion problems. In forest farming, a high value of farm and assets has a negative effect, while belonging to informal groups has a positive effect pointing to characteristics that do not belong to traditional farmers.adoption, attitudes, forest farming, habitus, interest, riparian, Institutional and Behavioral Economics,