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241.
Robert M. O'Keefe 《The Journal of the Operational Research Society》1989,40(5):415-422
Cognitive style refers to differences that can be perceived in individuals due to differing cognitive structures. There has been a large amount of research on how cognitive style affects managerial decision-making, particularly in the context of management information systems, but little or no attempt to relate these findings to operational research. This paper reviews the findings of cognitive-style research from the perspective of operational research, and draws a number of useful inferences concerning the matching of OR aids to managers, the presentation of information and recommendations, the use and acceptance of OR, and the structure of OR groups. Further, it is argued that cognitive-style findings help to give a justification to the move towards ‘soft’ approaches to analysis. 相似文献
242.
243.
The existence and uniqueness of classical global solutions to a type of Boussinesq equations with initial and boundary values are studied in this paper. The existence of such solutions is proved by means of compactness theorem and Schauders fixed point theorem, and its uniqueness by the so called energy method.Projects Supported by the Science Fund of the Chinese Academy of Sciences. 相似文献
244.
B. R. Harvey M. B. Lovett S. J. Boggis 《Journal of Radioanalytical and Nuclear Chemistry》1987,115(2):357-368
Selected experiences in the control of contamination and the threat it poses to the quality of analytical date are discussed in the context of the whole analytical process from collection of marine environmental samples, through handling and radiochemical separation, to the final interpretation of results. Examples include a demonstration of the contamination introduced during sediment core sectioning, contamination of sea water by a ship's pumping system, and the effect of filtration on the apparent partitioning of radionuclides between solid and liquid phases of sea water. 相似文献
245.
William F. Bowlin 《The Journal of the Operational Research Society》1987,38(2):127-135
The objective of this research is to evaluate a new methodology, data envelopment analysis (DEA), as a tool for measuring and evaluating the operational efficiency of US Air Force organizations. This study involves the application of DEA to locate possible inefficiencies in the performance of US Air Force real-property maintenance activities. Dynamic behaviour, as exhibited via window analyses, is reviewed along with static counterparts. The testing was done in close coordination with Air Force officials, who reviewed the results for accuracy, validity and relevance. We conclude that this type of efficiency analysis does have value for the Air Force, where it can serve as a guide to auditors, budget programmers, managers and others in measuring, evaluating and enhancing operational efficiency. 相似文献
246.
激光诱导荧光探测水体中溶解有机物浓度 总被引:2,自引:2,他引:0
用Nd∶YAG激光器的三倍频355 nm光作为激发光源,根据激光诱导荧光(LIF)方法激发并探测污染水体的荧光光谱.通过对荧光光谱的分析处理研究归一化荧光强度,即450 nm处水中溶解有机物(DOM)峰与405 nm处水的拉曼峰的比值,反演溶解有机物浓度.用商品腐殖酸和去离子水配置成已知浓度的溶液代替标准DOM溶液进行标定,得到回归方程.结果证明,DOM的归一化荧光强度与水体中DOM浓度有较好的线性关系,因此LIF方法是对大面积水域水质进行动态遥测的较理想方法. 相似文献
247.
The acoustic field inside a shell excited by a spatially inhomogeneous harmonic pressure field is studied. The shell is assumed
to have a finite length, a set of orthogonal stiffening ribs, two ends bounding the acoustic volume, and a sound-insulating
structure, which includes layers of sound-insulating material, resonant elements, and an interior panel. The shell is considered
to be orthotropic with boundary conditions corresponding to a free support. For the acoustic field in the closed volume, analytical
expressions are derived with allowance for the elastoacoustic interaction of the shell with the sound-insulating layers and
with the medium both inside the shell (with arbitrary impedance values at the ends) and outside it. These expressions are
used to investigate the effect of different types of resonant systems on the sound field inside the shell. 相似文献
248.
Yu. V. Vasil’ev R. R. Abzalimov Sh. K. Nasibullaev R. F. Tuktarov F. Hauke U. Reuther A. Hirsch T. Drewello 《Physics of the Solid State》2002,44(3):554-556
The formation and decay of negative molecular ions of azafullerenes and their hydrogenated derivatives are investigated by mass spectrometry. The mechanisms of resonant electron capture and the lifetimes of negative molecular ions with respect to the electron autodetachment in azafullerene molecules are discussed. A comparative analysis of the data obtained for azafullerenes and hydrogenated fullerene derivatives is carried out. 相似文献
249.
Evstafyeva I. T. Bozhenkov G. V. Aizina Ya. A. Rozenzveig I. B. Ermakova T. G. Levkovskaya G. G. Mirskova A. N. 《Russian Journal of Organic Chemistry》2002,38(8):1178-1182
1H-Pyrazoles, triazoles, and imidazoles in reaction with ethoxycarbonylimine and arylsulfonylimines of chloral yield addition products, corresponding 1-(1-amidotrichloroethyl)azoles. Derivatives of 1-alkylpyrazoles and pyrazolones react with chloral 4-chlorophenylsulfonylimine to furnish products of C-amidotrichloroethylation into position 4 of the azole ring. 相似文献
250.
The effect of hydrogen on the photoluminescence and planar conductivity of GaAs/InGaAs quantum-well heterostructures with an island Pd layer at the anodically oxidized surface was studied. Unlike continuous deposited Pd layers, island layers do not cause the formation of defects in the GaAs surface region and yet the Pd layer maintains high catalytic activity with respect to hydrogen. It is found that the thermal treatment of such a structure in a hydrogen atmosphere causes atomic-hydrogen passivation of the defects in quantum wells. Studies of the characteristics of planar photoresistors with an island Pd layer acting as hydrogen sensors show that their hydrogen detectivity is approximately two orders of magnitude higher than that of diode structures with continuous Pd layers. 相似文献