Conservation Reserve Program Participation and Acreage Enrollment of Working Farms

Among Conservation Reserve Program (CRP) participants, there is a distinction between farm households using the program to ease out of farming and those using the program to augment production receipts. We find evidence that factors other than farm profitability and environmental factors may influence program participation of farmers who continue agricultural production. Program payments and farm size positively correlate with the amount of land enrolled in the CRP, and characteristics of participants in land retirement and working-lands CRP components are similar.Environmental Economics and Policy,

Exploring Farm Business and Household Expenditure Patterns and Community Linkages

Farm operators are an integral part of some rural economies. The businesses they operate often hire seasonal and full-time employees and purchase goods and services from local farm implement dealers, input suppliers, and financial institutions. Farm household spending on food, furniture and appliances, trucks and automobiles, and a range of consumer goods also support local jobs and retail businesses in some communities. Based on the 2002 agricultural census and the 2004 Agricultural Resource Management Survey, this paper explores the linkages between farm household/ business expenditures and local communities.Farm business expenditures, farm household spending, employment, community linkage, Consumer/Household Economics, Farm Management, Community/Rural/Urban Development,

Lorentz Invariant Spacelike Surfaces of Constant Mean Curvature in Anti-de Sitter 3-Space

In this thesis, I studied Lorentz invariant spacelike surfaces with constant mean curvature H = c in the anti-de Sitter 3-space H31(−c2) of constant curvature −c2. In particular, I construct Lorentz invariant spacelike surfaces of constant mean curvature c and maximal Lorentz invariant spacelike surfaces in H31(−c2). I also studied the limit behavior of those constant mean curvature c surfaces in H31(−c2). It turns out that they approach a maximal catenoid in Minkowski 3-space E31 as c → 0. The limit maximal catenoid is Lorentz invariant in E31

Un indicateur de fausses couleurs pour évaluer le traitement des images couleurs

National audienceDans le cas particulier du filtrage (lissage, rehaussement, etc.) d'images couleurs, les approches proposées peuvent faire apparaître dans l'image résultat des distorsions colorimétriques appelées alors "fausses couleurs", c'est-à-dire des couleurs indésirables non présentes dans l'image initiale. Parmi les nombreux indicateurs permettant d'évaluer les performances d'un filtrage, il n'existe pas actuellement de solution pour évaluer la quantité de fausses couleurs introduites dans l'image résultat. Le travail présenté propose un nouvel indicateur numérique, noté IFC pour Indicateur de Fausses Couleurs, capable de quantifier l'apparition de ces fausses couleurs. Cet indicateur peut être vu comme une mesure de performance du traitement au même titre que le rapport signal sur bruit. Les résultats proposés montrent que l'indicateur construit rend bien compte de la quantité de fausses couleurs introduites dans le résultat d'un filtrage

Automatic difference measure between movies using dissimilarity measure fusion and rank correlation coefficients

International audienceWhen considering multimedia database growth, one current challenging issue is to design accurate navigation tools. End user basic needs, such as exploration, similarity search and favorite suggestions, lead to investigate how to find semantically resembling media. One way is to build numerous continuous dissimilarity measures from low-level image features. In parallel, an other way is to build discrete dissimilarities from textual information which may be available with video sequences. However, how such different measures should be selected as relevant and be fused ? To this aim, the purpose of this paper is to compare all those various issimilarities and to propose a suitable ranking fusion method for several dissimilarities. Subjective tests with human observers on the CITIA animation movie database have been carried out to validate the model

DEMAND ESTIMATION FOR AGRICULTURAL PROCESSING CO-PRODUCTS

Co-products of processing agricultural commodities are often marketed through private transaction rather than through public markets or those in which public transaction information is recorded or available. The resulting lack of historical price information prohibits the use of positive time series techniques to estimate demand. Demand estimates for co-products are of value to both livestock producers, who obtain them for use in livestock rations, and processors, who must sell or otherwise dispose of them. Linear programming has long been used, first by researchers and later as a mainstream tool for nutritionists and producers, to formulate least-cost livestock rations. Here it is used as a normative technique to estimate step function demand schedules for co-products by individual livestock classes within a crop-reporting district. Regression is then used to smooth step function demand schedules by fitting demand data to generalized Leontief cost functions. Seemingly unrelated regression is used to estimate factor demand first adjusted for data censoring using probit analysis. Demand by individual livestock classes is aggregated over the number of livestock within a region. Quantities demanded by beef cows for each of the three co-products considered, sugarbeet pulp, wheat middlings, and potato waste, are large relative to other species because of their predominance in the district. At the current price for sugarbeet pulp, quantity demanded by district livestock is low. However quantity demanded is price elastic and becomes much greater at lower prices. Wheat middlings can be an important component of livestock rations, even at higher prices. At a price slightly below the current price, local livestock demand would exhaust the wheat middlings produced at the district's only wheat processing plant. Potato waste is most appropriate for ruminant diets because these animals are able to consume a large quantity of this high moisture feedstuff. Potato waste can be a cost-effective component in beef and dairy rations. Practically, livestock markets for potato waste must be in close proximity to a potato processing plant. Its high moisture content limits the distance it can be economically transported. At current prices, potato waste can be economically included in the ration for beef cows on a farm nearly 100 miles from the processing plant, although storage challenges may restrict use of the feed to closer operations.co-products, demand estimation, econometrics, linear programming, Agribusiness,

DEMAND ESTIMATION FOR AGRICULTURAL PROCESSING CO-PRODUCTS

Co-products of processing agricultural commodities are often marketed through private transaction rather than through public markets or those in which public transaction information is recorded or available. The resulting lack of historical price information prohibits the use of positive time series techniques to estimate demand. Demand estimates for co-products are of value to both livestock producers, who obtain them for use in livestock rations, and processors, who must sell or otherwise dispose of them. Linear programming has long been used, first by researchers and later as a mainstream tool for nutritionists and producers, to formulate least cost livestock rations. Here it is used as a normative technique to estimate step function demand schedules for co-products by individual livestock classes within a region. Regression is then used to smooth step function demand schedules by fitting demand data to generalized Leontief cost functions. Seemingly unrelated regression is used to estimate factor demand first adjusted for data censoring using probit analysis. Demand by individual livestock classes is aggregated over the number of livestock within a region. Species important to demand for each co-product are identified and own price elasticity for individual livestock classes and all livestock are estimated.Agribusiness, Demand and Price Analysis,

\u3cem\u3ep\u3c/em\u3e-Value Histograms: Inference and Diagnostics

It is increasingly common for experiments in biology and medicine to involve large numbers of hypothesis tests. A natural graphical method for visualizing these tests is to construct a histogram from the p-values of these tests. In this article, we examine the shapes, both regular and irregular, that these histograms can take on, as well as present simple inferential procedures that help to interpret the shapes in terms of diagnosing potential problems with the experiment. We examine potential causes of these problems in detail, and discuss potential remedies. Throughout, examples of irregular-looking p-value histograms are provided and based on case studies involving real biological experiments

Development of Temperature Gradient Frequency Distribution for Kenyan Cement Concrete Pavement: Case Study of Mbagathi Way, Nairobi.

In this paper, it is recognised that the Dutch Design method can be applied in Kenya to develop cement concrete pavements. A major design parameter required for this application is temperature gradient frequency distribution which is still lacking for Kenya, and is the major focus of this paper. The dowel jointed concrete pavement (DJCP) at rehabilitated Mbagathi Way, Nairobi is used as a case study. The limited surface temperature measurements carried out at Mbagathi Way, Nairobi in conjunction with BELLS3 model are used to develop the distribution. The distribution is compared against the default Dutch distribution from which it is seen that the Kenyan distribution has higher values for higher temperature gradient classes. This is, partly, attributed to higher quantities of solar energy in Kenya as compared to the Netherlands. Keywords: Temperature gradient frequency distribution; BELLS3 mode

Spatio-temporal block model for video indexation assistance

International audienceIn the video indexing framework, we have developed a user assistance system in order to define concept models (i.e semantic index) according to features automatically extracted from the video. Because the manual indexing is a long and tedious task, we propose to focus the user attention on pre-selected prototypes that a priori correspond to the searched concepts. The proposed system is decomposed in three steps. In the first one, some basic spatio-temporal blocks are extracted from the video, a particular block being associated to a particular property of one feature. In the second step, a Question/Answer system allows the user to define links between basic blocks in order to define concept block models. And finally, some concept blocks are extracted and proposed as prototypes of the concepts. In this paper, we present the two first steps, particularly the block structure, illustrated by an example of video indexing that corresponds to the concept running in athletic videos