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141.
ABSTRACT This is an overview of the application of digital computers to the Maintenance Planning function and to the Maintenance Engineering support role of a large open pit BWE/conveyor mining operation. The benefits to Suncor Mine Maintenance are highlighted so this paper will be of interest to any group contemplating the installation of computers to improve productivity and flexibility. 相似文献
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Current models of reading and speech perception differ widely in their assumptions regarding the interaction of orthographic and phonological information during language perception. The present experiments examined this interaction through a 2-alternative, forced-choice paradigm, and explored the nature of the connections between graphemic and phonemic processing subsystems. Exps 1 and 2 demonstrated a facilitation-dominant influence (i.e., benefits exceed costs) of graphemic contexts on phoneme discrimination, which is interpreted as a sensitivity effect. Exps 3 and 4 demonstrated a symmetrical influence (i.e., benefits equal costs) of phonemic contexts on grapheme discrimination, which can be interpreted as either a bias effect, or an equally facilitative/inhibitory sensitivity effect. General implications for the functional architecture of language processing models are discussed, as well as specific implications for models of visual word recognition and speech perception. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
144.
Keulen Ron F.; Adam Jos J.; Fischer Martin H.; Kuipers Harm; Jolles Jelle 《Canadian Metallurgical Quarterly》2002,28(3):515
Students participated in 3 experiments investigating the use of environment- and action-centered reference frames in selective reaching. They pointed to a green target appearing either with or without a red distractor. Target-distractor distance was manipulated, and distractor interference (difference between distractor trials and no-distractor trials) was measured in reaction time, movement time, and movement endpoint. Target-distractor distance determined the dominant frame of reference. Small distances evoked an environment-centered framework that encoded targets within an external context. Large distances evoked an action-centered framework that encoded targets relative to the start position of the hand. Results support the hypothesis that the brain represents spatial information in multiple frames of reference, with the dominant frame of reference being dependent on the task demands. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Tina M. Petersen Hanadi S. Rifai Monica P. Suarez A. Ron Stein 《Canadian Metallurgical Quarterly》2005,131(10):1414-1425
A pathogen impaired watershed in Houston, Tex., was studied to assess the spatial and temporal nature of point and nonpoint bacterial load contributions. End-of-pipe sampling at wastewater treatment plant effluent and storm sewers discharging under dry weather conditions was undertaken. Relatively low concentrations of E. coli were found in wastewater treatment effluent, with a geometric mean of 5 MPN/dL, while dry weather storm sewer discharges exhibited a geometric mean concentration of 212 MPN/dL. Loads from both point and nonpoint sources of E. coli were calculated and compared to in-stream bacteria loads. Nonpoint loads were estimated using an event mean concentration approach on an annual basis. Nonpoint source (NPS) loads were the primary source of bacteria loading to the bayou. Wastewater treatment plant and dry weather storm sewer loads, however, dominated in dry weather conditions. While NPS loads remained relatively constant from headwaters to the mouth of the bayou, point source loads exhibited greater spatial variability depending on the distribution of the discharging pipes. The study points to the need for spatial and temporal considerations in managing bacterial pollution in streams. 相似文献
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Although it is undeniable that the Poisson's effect on the behavior of a woven fabric is crucial, there have been relatively few papers devoted to this subject. In this study, a mechanical model for a woven fabric made of extensible yarns is developed to calculate the fabric Poisson's ratios. Theoretical results are compared with the available experimental data. A thorough examination on the influences of various mechanical properties of yarns and structural parameters of fabrics on the Poisson's ratios of a woven fabric is given. The prediction of Poisson's ratios in this paper will enable more rigorous studies on such important issues of fabric bending and draping behaviors. 相似文献
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Equipment effectiveness: OEE revisited 总被引:1,自引:0,他引:1
Overall equipment effectiveness (OEE) is a metric that has been accepted completely in the semiconductor industry. OEE is simple and clear, and standards and guidelines have been developed. Nonetheless, literature indicates imperfections in applying OEE with regard to time base and rate efficiency. As literature lacks a basic framework for OEE, effectiveness has been approached systematically that resulted in a new equipment effectiveness E. The main difference between OEE and E concerns the choice of the time base. OEE does include equipment-independent conditions, such as lack of input items. This condition is not caused by the equipment but by the environment of the equipment. E has been defined to get a performance measure that is related to equipment-dependent states only, viz. effective state consisting of productive state, scheduled down state, and unscheduled down state. Because of the stand-alone condition, the equipment effectiveness expresses the (equipment) internal losses, while utilization expresses the external losses. By using E, equipment can be compared and improved. It can be concluded that the advantage of E over OEE is that real equipment effectiveness is measured as the influence of utilization (equipment-independent conditions) is eliminated. 相似文献