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61.
62.
Judiesch Michael K.; Schmidt Frank L.; Mount Michael K. 《Canadian Metallurgical Quarterly》1992,77(3):234
Examined distributions of estimates of the dollar value of performance in studies employing the method of F. L. Schmidt et al (1979) for estimating the standard deviation of job performance (SDy) and found evidence that (1) the mean 50th percentile estimate is biased downward, (2) estimates of SDy appear to be a constant percentage of the 50th percentile estimate, and (3) estimates of SDy as a percentage of the 50th percentile value (SDp) are quite similar to empirical SDp values based on actual employee output. These findings suggest that the downward bias in the mean estimate of the 50th percentile causes the mean estimates of SDy to be similarly biased downward, but does not bias the estimates of SDp. Finally, an objective method for estimating the value of average employee output is described. The product of this value and the mean supervisory estimate of SDp yields an unbiased estimate of SDy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
The benefits of using a comprehensive annotation strategy (employing underlining/circling, making connections, asking questions, and making comments) with knowledge maps (spatial/verbal arrays) and traditional, linear text to improve free recall scores for learners with individual differences in vocabulary and comprehension ability were examined. Types and frequencies of annotations generated were also examined for each stimulus format condition. Multiple regression analyses indicate that the frequency of use of two component annotation strategies, asking questions and making connections, were significant predictors of recall scores, while frequency of underlining/circling and generating elaborations failed to predict recall scores. Text users generated more underlining/circling, while knowledge map users generated more connections between ideas, suggesting that knowledge maps may facilitate the application of more productive annotation strategies. Also examined were the interrelationships between vocabulary ability, comprehension ability, and free recall scores. Copyright 1997Academic Press 相似文献
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Tempest Philip R.; White Patricia; Williamson E.Diane; Titball Richard W.; Kelly David C.; Kemp Graham J.L.; Gray Peter M.D.; Forster Simon J.; Carr Frank J.; Harris William J. 《Protein engineering, design & selection : PEDS》1994,7(12):1501-1507
We have used the technique of antibody reshaping to producea humanized antibody specific for the a toxin of Clostridiumperfringens. The starting antibody was from a mouse hybridomafrom which variable (V) region nucleo-tide sequences were determined.The complementarity-determining regions (CDRs) from these Vregions were then inserted into human heavy and light chainV region genes with human constant region gene fragments subsequentlyadded. The insertion of CDRs alone into human frameworks didnot produce a functional reshaped antibody and modificationsto the V region framework were required. With minor frameworkmodifications, the affinity of the original murine mAb was restoredand even exceeded. Where affinity was increased, an alteredbinding profile to overlapping peptides was observed. Computermodelling of the reshaped heavy chain V regions suggested thatamino acids adjacent to CDRs can either contribute to, or distort,CDR loop conformation and must be adjusted to achieve high bindingaffinity. 相似文献
66.
We have measured the heat capacities of3He films and liquid3He in porous Vycor glass at 10 to 600 mK. With increasing the film thickness from 1 to 3 atomic layers, the specific heat evolves gradually from that typical to solid to that of liquid3He. At about 2 atomic layers, however, its low-temperature part is nearly temperature-independent; we interpret this as a result of gradual freezing of spins in an amorphous solid3He film with decreasing the temperature. The contribution of liquid3He in the center of the Vycor pores can be described as the specific heat of bulk liquid3He at corresponding pressures in the range 0 to 28 bar. The thickness of amorphous solid on the pore walls increases with external pressure roughly linearly. Preplating the walls with4He allows to determine the positions of3He atoms contributing to the surface specific heat at 10 to 50 mK. In addition, the contribution from the specific heat of3 He -4He mixing at 100 to 600 mK is discussed as a function of pressure and amount of4He.0n leave from ISSP Acad. Sci. of Russia, Chernogolovka, Russia 相似文献
67.
Frank V. Kosikowski 《Journal of dairy science》1985,68(9):2403-2410
Ultrafiltration and thermization of milk on dairy farms in France have been under study since 1979. More recently five dairy farms in Brittany have been routinely producing 2:1 whole milk retentate for Emmental and St. Paulin cheese making. The milk processed is ultrafiltered at 35°C and thermized at 72°C for 15 s in an Ultratherm unit. Cheese quality generally appears satisfactory.In Eastern France a new specialty cheese industry has been started utilizing 4.5:1 whole milk retentate produced by ultrafiltration conducted at 40°C. The specialty cheese attains its characteristic white surface from Penicillium album mold. It has a bland, nutty flavor and very soft, smooth texture. A surface bluing phenomenon occurs after 14 d. 相似文献
68.
着重介绍Raychem电路保护部的PolySwitch PPTC(聚合物正温度系数)元件在电源管理中提供电流过载和温度过载的保护过程。另外还介绍了电源适配器、CLA(点烟器)、移动电话设备及电池板的保护装置是如何进一步改善实际使用中的总体可靠性的。 相似文献
69.
Nickel molybdate catalysts used in several different upgrading reactions of coal-derived materials from low-rank Australian coals have been regenerated and their activity assessed using a number of physical and chemical techniques. Regeneration of spent coked catalysts for 20 hours in air at 450°C was sufficient to restore chemical hydrogenation activity to catalyst used for pre-asphaltene, asphaltene and oil upgrading, provided poisoning of the catalyst surface by other impurities, principally chlorine-containing molecules, had not occurred. 相似文献
70.