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71.
Three replica gratings were made from a single master; two were epoxy overcoated with different thicknesses of gold, and one was replicated directly in gold. Their performance in EUV light at grazing incidence angles was measured and compared. 相似文献
72.
本文描述一种采用常规的实验装置在短时间内测量土层非饱和水力传导率的简易方法,称为"向上入渗法".这一方法基于在控制压力的条件下测量土的吸水量,从而来估算土层在湿润状态下的水力传导系数.将其结果与恒定加水量法、小增量压力变化法、一步法以及杰克逊理论模型的计算结果进行了比较.采用向上入渗法与采用恒定加水量法的结果很接近,但稍大于一步法而小于杰克逊理论模型的结果.这种测定方法限定负压值约为一米. 相似文献
73.
74.
Ectomography, a general tomographic method currently being implemented in nuclear medicine, is described. The object is viewed from different directions from the same projection angle, and the reconstruction process can be described as a two-dimensional filtered back-projection technique. One limitation of this limited-angle approach is that a three-dimensional Fourier representation of the acquired projections has a cone where data are missing. This empty cone can cause distortions in the tomogram by insufficient elimination of details outside the reconstructed tomographic section and by distortion of details in the section. The degree of distortion is dependent on the extension of the object in all directions and on the projection angle. Despite these limitations ectomography can be superior to single-photon-emission computed tomography for imaging sections that are close and parallel to the surface of the object, as in imaging of the hip joint or the heart. 相似文献
75.
Hunter S Howard M Marki P Gelpi MJ Francone J Reed G McGinty K Mayes B Ysmael R Johnson C 《Food management》1992,27(1):92-5, 98
Consumer confidence is at its lowest ebb since 1980. Economic growth is at a standstill & unemployment & inflation are both rising. Here's a front-line report from more than three dozen operators who are fending off the recession's dual pressures of slow sales & rising costs. They are using discount pricing, partnering with vendors, setting pay for performance standards & a variety of other recession-beating practices. 相似文献
76.
77.
Kähkönen E Nykyri E Ilmarinen R Ketola R Lusa S Nygård CH Suurnäkki T 《Applied ergonomics》1992,23(3):186-190
A study was made of the appraisers' effect on the estimation of metabolic rate with the Edholm scale and a table of the ISO 7243 heat stress standard. The appraisers, five experienced and five inexperienced persons, estimated the metabolic rate of three different work tasks from videotapes. Analysis of variance indicated significant ( [Formula: see text] ) differences in the appraisers' recordings of the activities. The appraisers were grouped according to the similarity of the estimated values they gave. The groups thus contained both experienced and inexperienced appraisers, and it was not possible to classify the appraisers into experienced and inexperienced groups according to their earlier experience. The metabolic rates according to the Edholm scale were higher than according to the ISO 7243 table. The differences in metabolic rates given by the individual observers varied from 38 to 118 W/m(2). The variations in the estimation of metabolic rates were greater when the Edholm scale was used. This variation caused considerable variation also in the predicted mean vote, PMV index. It is recommended that the appraisers be selected carefully, because it is not possible to know whether a randomly selected appraiser is an 'average' or an 'extreme' appraiser without a test. Before conducting extensive field surveys where several appraisers estimate the metabolic rates, it would be useful to arrange training in order to calibrate the levels of the Edholm scale as well as ISO method among the appraisers because training clearly unified the estimation. 相似文献
78.
Goldblatt S 《Computers in healthcare》1992,13(9):29-31
Sunquest's president and chief executive officer, Sidney Goldblatt, M.D., says the inefficient way information is shared in healthcare is "stupid" and wouldn't be tolerated in other industries. Until the public becomes impatient and strident about flagrant waste and begins to demand most cost-effective methods in healthcare, true change will take a lot longer. 相似文献
79.
Schultz S 《Computers in healthcare》1992,13(13):32-4, 36-7
A group of 60 university hospitals and medical centers has evolved from its original goal of gaining greater purchasing clout to a new goal: The University Hospital Consortium is becoming an information corporation, with the enormous information potential to affect treatment outcomes, practice patterns and clinical research. Sam Schultz, UHC's vice president of Information Services, tells Computers in Healthcare his organization is on the verge of a new age of discovery. 相似文献
80.
Apple founder targets healthcare as NeXT market. Interview by Carolyn Dunbar and Michael L. Laughlin
Jobs S 《Computers in healthcare》1992,13(13):22-3, 25
Cofounder and former chairman of the board of Apple Computer Steven Jobs looks beyond the 1980s image of a petulant, embittered young man, fighting with all who failed to share his vision, and many who did. Today, as a founder, president and chairman of NeXT, Inc., he looks to more high-minded applications of his computer genius. 相似文献