PER UNIT COSTS TO OWN AND OPERATE FARM MACHINERY

Entropy and jackknife estimation procedures were used to find that custom rates are 20.3% lower than the true cost to own and operate machinery for an average size Kansas farm. A method was then developed to estimate a farms total machinery costs with which to benchmark machinery costs.Farm Management,

USE OF ALTERNATIVE DEPRECIATION METHODS TO ESTIMATE FARM TRACTOR VALUES

Six depreciation methods were used to simulate the value of farm tractors with indexed and expected prices. Accuracy of simulated values was evaluated using paired t-tests of mean absolute percentage errors and forecast accuracy regression models. Results varied with age and use. Some depreciation methods were more accurate than others.Farm Management, Financial Economics,

Data exchange for web site content and resource sharing

At the MPI for Psycholinguistics we launched a new web site (www.mpi.nl) on April 20, 2009. The web site is created in the Content Management System Plone. Our Plone CMS communicates with three data bases: 1. The MPI people data base: The interaction between the data base and the CMS is through a python script which allows us to create standard person pages for each MPI member. Person pages have a default person home set-up, a standard sub folder structure and some extra functionality to create user specific content. 2. The MPDL PubMan data base. Every night our CMS retrieves the metadata from the PubMan data base and stores these in the CMS using a python script. Researchers can specify a set of criteria to select the publications they wish to show on the publication folder of their person pages. The display can either be set to sort the publications by year, or by publication type or a combination of the two. A special (and hidden) 'local tag' element in the PubMan metadata set has been created to either create a collection for special publications or to exclude publications to be presented on the web page. In addition, research group and projects can create publications list based on the research group or project name. The MPDL metadata accomodates persistent links to the full text which can be viewed directly from the website when set at Public (in PubMan). In case the publication is set at Private a request form will appear with which users can send a request to our Library. The MPDL metadata also accomdates persistent links to the MPI-psycholinguistics research data archive. This allows the users to store supplementary material (primary data) in this archive and to link it to the PubMan data base. On the web site it will show automatically if the publiaction has supplementary material. 3. The MPI research data archive At our institute we house a primary research data archive. From the web site links can be created to these data, which will provide an alternative (and more public friendly) manner of showing the data. To realize the communication between the CMS and the three data bases has been quite a technical and organisational challenge, involving a lot of commitment from the MPDL team members and from the institute staff involved in the development of the web site (library, techical support). We feel that the functionality we have created is complex, but very nice and -easy-to-be-used- by other MPI institutes with a Plone based web site

Calibration of liquid argon and neon detectors with 83Krm^{83}Kr^m

We report results from tests of $^{83}$Kr$^{\mathrm{m}}$, as a calibration source in liquid argon and liquid neon. $^{83}$Kr$^{\mathrm{m}}$ atoms are produced in the decay of $^{83}$Rb, and a clear $^{83}$Kr$^{\mathrm{m}}$ scintillation peak at 41.5 keV appears in both liquids when filling our detector through a piece of zeolite coated with $^{83}$Rb. Based on this scintillation peak, we observe 6.0 photoelectrons/keV in liquid argon with a resolution of 6% ($\sigma$/E) and 3.0 photoelectrons/keV in liquid neon with a resolution of 19% ($\sigma$/E). The observed peak intensity subsequently decays with the $^{83}$Kr$^{\mathrm{m}}$ half-life after stopping the fill, and we find evidence that the spatial location of $^{83}$Kr$^{\mathrm{m}}$ atoms in the chamber can be resolved. $^{83}$Kr$^{\mathrm{m}}$ will be a useful calibration source for liquid argon and neon dark matter and solar neutrino detectors.Comment: 7 pages, 12 figure

Dinâmica da agricultura no polo de produção de soja do Estado de Mato Grosso.

Agricultural dynamics in Brazil continue to be characterized by two sharply contrasting forms. On one hand, low-efficiency production and natural resource extraction systems remain widely practiced along Brazil?s agricultural frontier. On the other hand, one also finds an agriculture characterized by the adoption of high-tech practices and high levels of productivity that raise Brazil?s competitiveness in international commodity markets. Such contrasts have long raised questions about the sustainability of Brazil?s agricultural production, and they have led to conflicts among some public policies promoted by various federal government agencies. This project mapped agricultural land use, between 2005-2009, in the center of Mato Grosso?s grain production zone in order to compare the dynamics of agricultural extensification vs. intensification of production. The analysis was based on the spectral profiles of vegetation index time-series data from MODIS, which allowed for identifying and mapping areas used for single and double-cropping of grains. The results show that the area of single-cropping was practically stable during the study period, while the area of double-cropping grew from being 20% of the single-cropping area in 2005 to more than 50% in 2009. These results make evident the need for the federal government to reconcile conflicting conservationist and developmentalist public policies in governing Brazilian agribusiness, for if it does not, the high and well recognized productive potential of Brazilian agriculture may be compromised

Classifying multiyear agricultural land use data from Mato Grosso using time-series MODIS vegetation index data.

MODIS 250-m NDVI and EVI datasets are now regularly used to classify regional-scale agricultural land-use practices in many different regions of the globe, especially in the state of Mato Grosso, Brazil, where rapid land-use change due to agricultural development has attracted considerable interest from researchers and policy makers. Variation exists in which MODIS datasets are used, how they are processed for analysis, and what ground reference data are used. Moreover, various and-use/land-cover classes are ultimately resolved, and as yet, crop-specific classifications (e.g. soy?corn vs. soy?cotton double crop) have not been reported in the literature, favoring instead generalized classes such as single vs. double crop. The objective of this study is to present a rigorous multiyear evaluation of the applicability of time-series MODIS 250-m VI data for crop classification in Mato Grosso, Brazil. This study shows progress toward more refined crop-specific classification, but some grouping of crop classes remains necessary. It employs a farm field polygon-based ground reference dataset that is unprecedented in spatial and temporal coverage for the state, consisting of 2003 annual field site samples representing 415 unique field sites and five crop years (2005-2009). This allows for creation of a dataset containing "best-case" or "pure" pixels, which we used to test class separability in a multiyear cross validation framework applied to boosted decision tree classifiers trained on MODIS data subjected to different pre-processing treatments. Reflecting the agricultural landscape of Mato Grosso as a whole, cropping practices represented in the ground reference dataset largely involved soybeans, and soy-based classes (primarily double crop "soy-commercial" and single crop "soy-cover") dominated the analysis along with cotton and pasture. With respect to the MODIS data treatments, the best results were obtained using date-ofacquisition interpolation of the 16-day composite VI time series and outlier point screening, for which five-year out-of-sample accuracies were consistently near or above 80% and Kappa values were above 0.60. It is evident that while much additional research is required to fully and reliably differentiate more specific crop classes, particular groupings of cropping strategies are separable and useful for a number of applications, including studies of agricultural intensification and extensification in this region of the world

Dinâmica da agricultura no polo de produção de soja do Estado de Mato Grosso.

Adotando um protocolo de estimativa de área probabilístico, de baixo custo e baseado no uso de séries históricas de imagens públicas de índice de vegetação, este trabalho teve como objetivo principal mapear e avaliar a dinâmica das áreas utilizadas para a produção da safra e da safrinha, no período compreendido entre 2005 e 2009, no polo de produção de grãos do Estado do Mato Grosso para avaliar o impacto do processo de intensificação relacionado à dinâmica de expansão da área de safrinha.SBSR 2011

Cropland area estimates using Modis NDVI time series in the state of Mato Grosso, Brazil.

The objective of this work was to evaluate a simple, semi?automated methodology for mapping cropland areas in the state of Mato Grosso, Brazil. A Fourier transform was applied over a time series of vegetation index products from the moderate resolution imaging spectroradiometer (Modis) sensor. This procedure allows for the evaluation of the amplitude of the periodic changes in vegetation response through time and the identification of areas with strong seasonal variation related to crop production. Annual cropland masks from 2006 to 2009 were generated and municipal cropland areas were estimated through remote sensing. We observed good agreement with official statistics on planted area, especially for municipalities with more than 10% of cropland cover (R2 = 0.89), but poor agreement in municipalities with less than 5% crop cover (R2 = 0.41). The assessed methodology can be used for annual cropland mapping over large production areas in Brazil