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151.
152.
This paper addresses the aging behaviour of NiCr/CuNiMn/NiCr triple layers on Al2O3 ceramics at temperatures up to 200°C for film thicknesses d0.5 μm. Investigations of the film structure and the increase of resistance and its temperature coefficient during the annealing process and studies of the dependence of this aging drift on both the film thickness and the storage temperature have been carried out. Furthermore, the film stress and the effect of substrate bending on resistance have been measured. The results can be explained by the irregular film structure (columns and small bridges between them), which causes stress and current concentrations as well as local creeping, cracking and oxidation processes in the micro-bridges. They are compared with such for structurally homogeneous films on silicon wafers. 相似文献
153.
154.
A new principle and arrangement for directly determining the angle of incidence of an optical beam on an object are proposed and demonstrated. The novelty of the approach lies in the realization of a ‘smart object’, which extracts a portion of the incident beam's power into an optical waveguide attached to the object's surface or embedded in its body for converting the angle of incidence into the position of a guided beam with finite lateral extent. This ‘integrated optical light pointer’ beam is accomplished by means of creating additional degrees of freedom on the target in two different ways. While a first type is based on introducing spatial variations of the waveguide thickness, a second type makes use of a chirp of the grating periodicity. The feasibility for practical applications has been experimentally demonstrated by a direct comparison with a commercial high-resolution encoder, resulting in an r.m.s. error of <30′'. Measurements have been performed for chips fabricated based on replicated polycarbonate substrates and with no external optics, showing the great potential of this approach for realizing low-cost yet high-performance miniature goniometers. 相似文献
155.
156.
Humanitarian psychological support as an organized field is relatively young. Pioneers in the field were involved primarily in providing psychological support to refugees and internally displaced persons in conflict and nonconflict situations. This article describes basic principles for the design of psychological support programs and interventions. The International Federation of Red Cross and Red Crescent Societies (IFRC) began a psychological support program in 1991. The IFRC chose psychological first aid as its model for implementation in developing countries. Psychological first aid fits all the principles for psychological support program design and is adapted to individual communities. The first generation of psychological support programs differed dramatically depending on the countries in which they were developed. A second generation of psychological support programs evolved in response to the earthquake/tsunami of December 26, 2004. The Inter-Agency Standing Committee international guidelines consolidated the advances of second-generation programs and provided a clear indication of the wide acceptance of the importance of psychological support. A glimpse is provided of the third generation of psychological support programs, and an admonition is made for a more empirical evaluation of the effectiveness of interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
157.
Contemporary approaches to the certification of measurement provision software are considered in domestic and overseas publications.
Normative documentation is analyzed and a scheme is proposed for certification that takes account of the features of programs
used for metrological purposes.
__________
Translated from Izmeritel’naya Tekhnika, No. 5, pp. 65–68, May, 2007. 相似文献
158.
煤气设施防腐实践及影响质量因素分析 总被引:1,自引:1,他引:0
根据近几年三明钢铁公司煤气设施的防腐实践,就影响煤气设施的质量因素进行了分析。 相似文献
159.
本文通过焊接试验对奥氏体不锈钢绕带容器环板与绕带焊接工艺进行了研究分析,并得出了合理的焊接方法和工艺参数。 相似文献
160.