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31.
A new stereological principle for test lines in three-dimensional space   总被引:2,自引:0,他引:2  
A new principle is presented to generate isotropic uniform random (IUR) test lines hitting a geometric structure in three-dimensional space (3D). The principle therefore concerns the estimation of surface area, volume, membrane thickness, etc., of arbitrary structures with piecewise smooth boundary. The principle states that a point-sampled test line on an isotropic plane through a fixed point in 3D is effectively an invariant test line in 3D. Particular attention is devoted to the stereology of particles, where an alternative to the surfactor method is obtained to estimate surface area. An interesting case arises when the particle is convex. The methods are illustrated with synthetic examples.  相似文献   
32.
冯明光  谢安国 《冶金能源》2004,23(1):6-8,26
利用寿命周期评价的思想,计算了炼铁生产过程中的环境负荷,并分析了各因素对环境负荷的影响,运用神经网络对炼铁生产过程环境负荷进行了预测。  相似文献   
33.
Gomatofu (sesame tofu) is one of the traditional Japanese healthy foods and is representative of all shojin (vegetarian) dishes. Gomatofu, one of the mixed gels consisting of kudzu (arrowroot) starch and sesame, possesses an extremely unusual textural characteristic which is soft, smooth, and springy. The textural properties are greatly influenced by preparation, ingredients and roasting conditions of sesame seeds. Hence there are many kinds of sesame materials which can be used to prepare gomatofu such as white, black, huskless or not and roasted or unroasted sesame materials, in this study, the effects of these materials on the physical properties of gomatofu were studied. The sample of Ra-W prepared with unroasted huskless sesame seed had the least hardness, but mouthfeel of this sample were the highest. The samples of Ro-B and Ro-W prepared with roasted husk (black and white) sesame seed were evaluated to have the best palatability because of their superior springiness. It was clarified that different kinds of sesame materials affected the forming of structure and physical properties of gomatofu, because the chemical components were different from varieties of sesame materials.  相似文献   
34.
中兴宽带线路测试技术及功能介绍   总被引:1,自引:0,他引:1  
宽带线路测试是中兴通讯ZXDSL综合宽带运维系统的核心功能,在DSL业务提供过程中主要应用在开通前的预测试、线路测试、开通后的例测试以及故障时的在线测试。对其测试技术和功能作了介绍。  相似文献   
35.
Thin hard coatings fracture propagation during the impact test   总被引:2,自引:0,他引:2  
One of the most significant applications of the impact test is to investigate thin hard coatings fatigue properties. Herein the test conditions and duration up to the film damage initiation, are considered in order to determine the critical stresses associated with the coating fatigue strength. Moreover, the subsequent film damage propagation is a significant mechanism as well, since it refers to the ability of the coating to withstand loads after its fatigue damage initiation. In order to describe the film fracture propagation the failed area ratio was introduced and an algorithm to determine this magnitude developed, based on the analysis of imprint scanning electron microscopy graphs. The application of the coating failed area ratio will be demonstrated in various impact test film cases, also with superficial thin layers. The top layers do not affect, in general, the failure initiation of the basic coating. However, according to the obtained results, the superficial films influence the basic coating failure propagation rate during the impact test.  相似文献   
36.
方华 《天津冶金》2003,(6):20-22
通过对国内外大量石油套管螺纹参数的测量和全尺寸的模拟试验,以及对测量和试验数据的理论分析,找出了影响国产套管发生粘扣的原因,并在实际生产中实施验证。采取相应的措施改善了套管的抗粘结性能,同时套管的密封和抗滑脱性能并未下降。  相似文献   
37.
介绍了天铁炼钢厂中间包水模实验原理和过程,分析了斜、直、圆三种型式挡渣墙模拟结果,提出了合理的挡渣控流方案,在生产实践中使用效果良好。  相似文献   
38.
In this paper we design an experiment which can be depicted as a simple scenario, a very limited 'world'. In this world, there are an actor that can pursue a project and an observer that is keeping its eyes on the actor. We try to show in the experiment that the observer can to some degree understand the actor based on its knowledge and some metaphors, i.e. understand what the actor is doing and why. As the conclusion of this experiment, we try to show some features of 'understanding'. These are (1) that 'understanding' has to be based on some preliminary knowledge; (2) that 'understanding' is a process of incremental learning; (3) that, as for symbolic systems, some metaphors are necessary for mapping real entities into concepts in mind.  相似文献   
39.
Experimental use of multi-functional desulfurizing agent TS-01 for FCC gasoline in the FCC unit of SINOPEC Jiujiang Company shows that the multi-functional desulfurizing agent can effectively remove various kinds of sulfur in FCC gasoline and diesel fuel and fulfill passivation on heavy metals.  相似文献   
40.
本文给出了作者开发的一个单处理机实时多任务操作系统的响应性能(响应时间,同步时间)的实验结果和/或估算。与国外同期文献发表的数据相比,指标先进。  相似文献   
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