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    Targeting Of Food Aid in Rural Ethiopia: Chronic Need or Inertia?

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    This paper identifies the factors driving the allocations of food aid in Ethiopia. We determine both how food aid is allocated across rural regions, reflecting the targeting criteria of the federal government, as well as how aid is allocated within regions, reflecting the decisions of local authorities and non-governmental organizations (NGOs). Devising a measure of "need" is difficult and controversial and there is no consensus on how to do so. It is agreed by most analysts that income is an imperfect measure of need, yet it is arguably the best single indicator of need in the absence of more detailed anthropometric information. Econometric analysis is used to examine the degree to which food aid is targeted according to pre-aid per capita household income, as well as to other factors. The paper also identifies factors associated with low incomes at regional- and household-levels, in order to be helpful to donors, NGOs and governments in their efforts to improve the targeting of food aid. Data are drawn from the Food Security Survey (FSS), fielded on a subset of the 1995/96 Annual Agricultural Sample Survey by the Ethiopian Central Statistical Authority. The data covers 4,112 households in 348 weredas. To examine the validity of the data, we calculated the amount of food aid received at the regional level from the FSS sample households and compared these results with actual food aid distribution records of the Disaster Prevention and Preparedness Commission (DPPC). The results showed striking similarities, and provide a robust external test of validity of the FSS and CSA data sets (Clay, Molla, and Debebe 1998).Food Security and Poverty, Downloads May 2008-July 2009: 32,

    Effects of Agricultural Commercialization on Food Crop Input Use and Productivity in Kenya

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    The objective of this report is to analyze the effects of smallholder commercialization on food crop input use and productivity in rural Kenya. The main research issues were: (1) To examine the determinants of smallholder fertilizer use on food crops, with a focus on the effects of household and regional agricultural commercialization; (2) To examine the determinants of food crop productivity, again with a focus on the effects of commercialization; and (3) To discuss the implications of the findings for policy and additional research necessary to improve the contribution of cash cropping to rural food productivity growth and food security. A main premise of the paper is that the effects of commercialization are not uniform and cannot be generalized. The effects are hypothesized to differ both according to differences in the institutional/contractual arrangements between firms and smallholders, management decisions, and the level of credit and extension support provided to smallholders by the various private and parastatal firms involved in promoting smallholder cash crops.food security, food policy, food crop productivity, food crop input, Crop Production/Industries, Productivity Analysis, Downloads May 2008 - July 2009: 78, Q18,

    Testing of High Voltage Surge Protection Devices for Use in Liquid Argon TPC Detectors

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    In this paper we demonstrate the capability of high voltage varistors and gas discharge tube arrestors for use as surge protection devices in liquid argon time projection chamber detectors. The insulating and clamping behavior of each type of device is characterized in air (room temperature), and liquid argon (90~K), and their robustness under high voltage and high energy surges in cryogenic conditions is verified. The protection of vulnerable components in liquid argon during a 150 kV high voltage discharge is also demonstrated. Each device is tested for argon contamination and light emission effects, and both are constrained to levels where no significant impact upon liquid argon time projection chamber functionality is expected. Both devices investigated are shown to be suitable for HV surge protection applications in cryogenic detectors.Comment: 22 pages, 18 figures v2: reduced file size for journal submissio

    Constraint and gauge shocks in one-dimensional numerical relativity

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    We study how different types of blow-ups can occur in systems of hyperbolic evolution equations of the type found in general relativity. In particular, we discuss two independent criteria that can be used to determine when such blow-ups can be expected. One criteria is related with the so-called geometric blow-up leading to gradient catastrophes, while the other is based upon the ODE-mechanism leading to blow-ups within finite time. We show how both mechanisms work in the case of a simple one-dimensional wave equation with a dynamic wave speed and sources, and later explore how those blow-ups can appear in one-dimensional numerical relativity. In the latter case we recover the well known ``gauge shocks'' associated with Bona-Masso type slicing conditions. However, a crucial result of this study has been the identification of a second family of blow-ups associated with the way in which the constraints have been used to construct a hyperbolic formulation. We call these blow-ups ``constraint shocks'' and show that they are formulation specific, and that choices can be made to eliminate them or at least make them less severe.Comment: 19 pages, 8 figures and 1 table, revised version including several amendments suggested by the refere

    Construction and Assembly of the Wire Planes for the MicroBooNE Time Projection Chamber

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    In this paper we describe how the readout planes for the MicroBooNE Time Projection Chamber were constructed, assembled and installed. We present the individual wire preparation using semi-automatic winding machines and the assembly of wire carrier boards. The details of the wire installation on the detector frame and the tensioning of the wires are given. A strict quality assurance plan ensured the integrity of the readout planes. The different tests performed at all stages of construction and installation provided crucial information to achieve the successful realisation of the MicroBooNE wire planes.Comment: 24 pages, 22 figures, accepted for publication as Technical Report in JINS

    A Catalogue of Morphologically Classified Galaxies from the Sloan Digital Sky Survey: North Equatorial Region

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    We present a catalogue of morphologically classified bright galaxies in the north equatorial stripe (230 deg2^2) derived from the Third Data Release of the Sloan Digital Sky Survey (SDSS). Morphological classification is performed by visual inspection of images in the gg band. The catalogue contains 2253 galaxies complete to a magnitude limit of r=16r=16 after Galactic extinction correction, selected from 2658 objects that are judged as extended in the photometric catalogue in the same magnitude limit. 1866 galaxies in our catalogue have spectroscopic information. A brief statistical analysis is presented for the frequency of morphological types and mean colours in the catalogue. A visual inspection of the images reveals that the rate of interacting galaxies in the local Universe is approximately 1.5% in the r≤16r\le16 sample. A verification is made for the photometric catalogue generated by the SDSS, especially as to its bright end completeness.Comment: Accepted for publication in Astronomical Journal. Table 2 available at http://www.icrr.u-tokyo.ac.jp/~fukugita/MCGpaper/table2.tx
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