2,398 research outputs found

    Considerations for Estimating Remote Operator Dust Exposure Using Fixed-Point Samples on Continuous Mining Sections

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    Respirable dust studies were conducted at several underground coal mining operations to evaluate and compare the dust measurements of fixed-point machine-mounted samples on a continuous miner and personal samples of the remote miner operator. Fixed-point sampling was conducted at the right rear corner of the continuous miner which corresponded to the traditional location of the operator\u27s cab. Although it has been documented that higher concentrations of dust are present at the machine-mounted position, this work sought to determined whether a relationship exists between the concentrations at the fixed-point position and the dust levels experienced at the remote operator position and whether this relationship could be applied on a industry-wide basis. To achieve this objective, gravimetric samplers were used to collect respirable dust data on continuous miner sections. These samplers were placed at a fixed position at the cab location of the continuous mining machine and on or near the remote miner operator during the 1 shift/day sampling periods. Dust sampling took place at mines with a variety of geographic locations and in-mine conditions. The dust concentration data collected at each site and for each sampling period were reduced to ratios of fixed-point to operator concentration. The ratios were calculated to determine similarities, differences, and/or variability at the two positions. The data show that dust concentrations at the remote operator position were always lower than dust concentrations measured at the fixed-point continuous miner location. However, the ratios of fixed-point to remote operator dust levels showed little consistency from shift to shift or from operation to operation. The fact that these ratios are so variable may introduce some uncertainty into attempting to correlate dust exposures of the remote operator to dust levels measured on the continuous mining machine

    Neural Networks, Logistic Regression, and Calibration: A Reply

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68566/2/10.1177_0272989X9801800414.pd

    A generalization of Schur-Weyl duality with applications in quantum estimation

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    Schur-Weyl duality is a powerful tool in representation theory which has many applications to quantum information theory. We provide a generalization of this duality and demonstrate some of its applications. In particular, we use it to develop a general framework for the study of a family of quantum estimation problems wherein one is given n copies of an unknown quantum state according to some prior and the goal is to estimate certain parameters of the given state. In particular, we are interested to know whether collective measurements are useful and if so to find an upper bound on the amount of entanglement which is required to achieve the optimal estimation. In the case of pure states, we show that commutativity of the set of observables that define the estimation problem implies the sufficiency of unentangled measurements.Comment: The published version, Typos corrected, 40 pages, 2 figure

    Precision Farming by Cotton Producers in Six Southern States: Results from the 2001 Southern Precision Farming Survey

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    Precision Farming by Cotton Producers in Six Southern States: Results from the 2001 Southern Precision Farming Surveycotton, precision farming, survey, Agribusiness, Farm Management, Production Economics, Research and Development/Tech Change/Emerging Technologies,

    Moving Towards the Post p < 0.05 Era via the Analysis of Credibility

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    It is now widely accepted that the techniques of null hypothesis significance testing (NHST) are routinely misused and misinterpreted by researchers seeking insight from data. There is, however, no consensus on acceptable alternatives, leaving researchers with little choice but to continue using NHST, regardless of its failings. I examine the potential for the Analysis of Credibility (AnCred) to resolve this impasse. Using real-life examples, I assess the ability of AnCred to provide researchers with a simple but robust framework for assessing study findings that goes beyond the standard dichotomy of statistical significance/nonsignificance. By extracting more insight from standard summary statistics while offering more protection against inferential fallacies, AnCred may encourage researchers to move toward the post p < 0.05 era

    Bison movements change with weather: Implications for their continued conservation in the Anthropocene

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    Animal movement patterns are affected by complex interactions between biotic and abiotic landscape conditions, and these patterns are being altered by weather variability associated with a changing climate. Some animals, like the American plains bison (Bison bison L.; hereafter, plains bison), are considered keystone species, thus their response to weather variability may alter ecosystem structure and biodiversity patterns. Many movement studies of plains bison and other ungulates have focused on point-pattern analyses (e.g., resource-selection) that have provided information about where these animals move, but information about when or why these animals move is limited. For example, information surrounding the influence of weather on plains bison movement in response to weather is limited but has important implications for their conservation in a changing climate. To explore how movement distance is affected by weather patterns and drought, we utilized 12-min GPS data from two of the largest plains bison herds in North America to model their response to weather and drought parameters using generalized additive mixed models. Distance moved was best predicted by air temperature, wind speed, and rainfall. However, air temperature best explained the variation in distance moved compared to any other single parameter we measured, predicting a 48% decrease in movement rates above 28°C. Moreover, severe drought (as indicated by 25-cm depth soil moisture) better predicted movement distance than moderate drought. The strong influence of weather and drought on plains bison movements observed in our study suggest that shifting climate and weather will likely affect plains bison movement patterns, further complicating conservation efforts for this wide-ranging keystone species. Moreover, changes in plains bison movement patterns may have cascading effects for grassland ecosystem structure, function, and biodiversity. Plains bison and grassland conservation efforts need to be proactive and adaptive when considering the implications of a changing climate on bison movement patterns

    Precision Farming by Cotton Producers in Eleven Southern States: Results from the 2005 Southern Precision Farming Survey

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    Precision Farming by Cotton Producers in Eleven Southern States: Results from the 2005 Southern Precision Farming Surveycotton, precision farming, survey, Agribusiness, Farm Management, Production Economics, Research and Development/Tech Change/Emerging Technologies,

    Identifying and Defining the Dimensions of Community Capacity to Provide a Basis for Measurement

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    Although community capacity is a central concern of community development experts, the concept requires clarification. Because of the potential importance of community capacity to health promotion, the Division of Chronic Disease Control and Community Intervention, Centers for Disease Control and Prevention (CDC), convened a symposium in December 1995 with the hope that a consensus might emerge regarding the dimensions that are integral to community capacity. This article describes the dimensions that the symposium participants suggested as central to the construct, including participation and leadership, skills, resources, social and interorganizational networks, sense of community, understanding of community history, community power, community values, and critical reflection. The dimensions are not exhaustive but may serve as a point of departure to extend and refine the construct and to operationalize ways to assess capacity in communities.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67070/2/10.1177_109019819802500303.pd
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