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1.
The proliferation of both online and bricks and mortar outlet stores underscores the observation that secondary markets are readily accessible to retailers of short-life-cycle products. These secondary markets provide recourse channels for retailers to sell excess inventory of out-of-favor items at reduced prices when overstocking occurs in a primary market. We study the problem of determining when a retailer should terminate its primary selling season by selling remaining inventory on a secondary market. The retailer has a single opportunity to procure prior to a primary selling season consisting of multiple periods. Demand in each period is random, but correlated. At the end of each period, any remaining inventory incurs a holding cost. Then, based upon the current level of inventory and the cumulative demand-to-date, the retailer decides either to terminate the primary selling season by selling all or part of the remaining inventory on a secondary market, or to extend the current primary selling season by another period. We develop structural properties of the optimal policy for determining when to terminate the primary selling season, and we develop corresponding implications for procurement. 相似文献
2.
Myers Nicholas D.; Payment Craig A.; Feltz Deborah L. 《Canadian Metallurgical Quarterly》2004,8(3):182
This study examined reciprocal relationships between collective efficacy and team performance over a season of competition in women's intercollegiate ice hockey within weekends where the opponent was constant for 2 games. Collective efficacy beliefs within 12 teams were assessed prior to both games for at least 7 weekends. Team performance indexes produced an overall measure of performance for each game. The average influence of Saturday collective efficacy on Saturday performance was moderate and positive after controlling for Friday performance. The average influence of Friday performance on Saturday collective efficacy was small and positive after removing the influence of Friday collective efficacy from Friday performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
Nicholas Biery Marc De Graef Jack Beuth Rafel Raban Andrew Elliott Tresa M. Pollock Curt Austin 《Metallurgical and Materials Transactions A》2002,33(10):3127-3136
Tensile experiments have been performed on specimens of four different investment-cast TiAl-based alloys with variations in
casting conditions. The average ductilities obtained in these experiments vary between approximately 0.8 to 2.0 pct plastic
strain to failure in tension. By using the three-parameter form of the Weibull relation, with the 0.2 pct offset yield strength
as the minimum failure strength, the resulting variability in the data can be quantified and is found to be similar for those
alloys with similar microstructural scale (grain size). Large variations in lamellar volume fraction, segregation, and phase
distribution have a minor influence on property variability, compared to changes in the scale of the grain structure caused
by either variations in cooling rate during casting or the addition of grain refiners. 相似文献
4.
Many engineering students enter and exit general chemistry courses with little appreciation of chemistry's relevance to other fields. At WPI many of these students go on to take introductory materials science and arrive with poor attitudes about chemistry and little retention of key concepts, but then become more engaged as they discover connections to engineering applications. Consequently, instructors in chemistry and mechanical engineering collaborated to augment general chemistry laboratories with explicit “bridges” to material properties and applications. Evaluation results showed that while students' attitudes toward chemistry were unaffected by bridging, particular aspects of the students' lab experience were enhanced to a statistically significant degree. Similar cross‐disciplinary collaborations might be considered elsewhere as a means of helping students find meaning and integrate subject matter, in a manner that is more feasible than large‐scale course or curriculum restructuring. 相似文献
5.
6.
This study used a pretest-posttest preexperimental design to examine the effect of a 10-week behavioral medicine support group intervention in a sample of persons with HIV. Using Solomon's psychoneuroimmunologic framework, the 10-week behavioral medicine program focused on the mind/body interaction, the relaxation response, coping with illness, hardiness, and nutrition. Pearson correlation coefficients and t tests were performed on the pre- and postintervention measures of hardiness, social support, immune function, and perceived health status. Results of the study indicated that hardiness (preintervention) and CD4 counts (pre- and postintervention) were significantly correlated with health status; however, CD4 counts decreased over the course of the behavioral medicine program. Implications for nursing and recommendations for further research are discussed. 相似文献
7.
8.
N. R. Bohidar Norman R. Bohidar Nicholas R. Bohidar 《Drug development and industrial pharmacy》1994,20(5):815-839
A discordant observation is a data point whose value is drastically different from that of the rest of the members in the data set. In the context of content uniformity experiments, however, a discordant observation arises in two ways: (i) when the value of an observation is markedly distant from that of the other data points even though it is within the required compendial range, and (ii) when the value of an observation is outside the permissible compendial range. Several statistical tests for detecting one or more discordant observations are presented. Since discordancy distorts the symmetricity of the data, several tests of symmetricity are provided. Tests for detection of group discordancy induced by discordant samples are also included. The compendial requirements are explained in statistical terms. The impact of discordant observations on compendial compliance requirements is assessed. The statistical basis of the construction of compendial limits as well as the assumptions implicit in the construction is elaborated. The results of the statistical analysis of three content uniformity studies are appropriately interpreted. 相似文献
9.
Mulcahy Nicholas J.; Call Josep; Dunbar Robin I. M. 《Canadian Metallurgical Quarterly》2005,119(1):23
Two important elements in problem solving are the abilities to encode relevant task features and to combine multiple actions to achieve the goal. The authors investigated these 2 elements in a task in which gorillas (Gorilla gorilla) and orangutans (Pongo pygmaeus) had to use a tool to retrieve an out-of-reach reward. Subjects were able to select tools of an appropriate length to reach the reward even when the position of the reward and tools were not simultaneously visible. When presented with tools that were too short to retrieve the reward, subjects were more likely to refuse to use them than when tools were the appropriate length. Subjects were proficient at using tools in sequence to retrieve the reward. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
Remote sensing of species mixtures in conifer plantations using LiDAR height and intensity data 总被引:2,自引:0,他引:2
Daniel N.M. Donoghue Peter J. Watt Nicholas J. Cox Jimmy Wilson 《Remote sensing of environment》2007,110(4):509-522
In even-aged, single species conifer plantations LiDAR height data can be modelled to provide accurate estimates of tree height and volume. However, it is apparent that growth models developed for single species stands are not directly transferable to a more general situation of mixed species plantations. This paper evaluates the ability of small footprint, dual-return, pulsed airborne LiDAR data to estimate the proportion of the productive species when mixed with a nurse crop in closed canopy plantations. A study area located in Galloway Forest District in Scotland is used as an example of Lodgepole pine and Sitka spruce mixed plantation; this area contains good examples of a wide range of pure and mixed species plantation types. Three species groups are studied: areas of pure Sitka spruce, areas of pure Lodgepole pine and areas where the two species have been planted together. Two approaches are assessed for detection of plantation mixtures: the first uses LiDAR intensity data to separate spruce and pine species and the second uses LiDAR-derived canopy density measures, coefficient of variation, skewness, percent of ground returns (which provides a measure of canopy openness) and the mean canopy height, which enables areas with height variations to be identified. From analysis of LiDAR data extracted from 54 study plots using logistic regression, the coefficient of variation and LiDAR intensity data provide the most useful predictors of the proportion of spruce in a pine/spruce mixture with coefficients of determination (R2) of 0.914 and 0.930 respectively. The method could be developed as a mapping tool, which in combination with existing inventory data should help to improve timber volume forecasting for mixed species even-aged plantations. 相似文献