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31.
The model-based human body motion analysis system   总被引:3,自引:0,他引:3  
In this paper, we propose a model-based method to analyze the human walking motion. This system consists of three phases: the preprocessing phase, the model construction phase, and the motion analysis phase. In the experimental results, we show that our system not only analyzes the motion characteristics of the human body, but also recognizes the motion type of the input image sequences. Finally, the synthesized motion sequences are illustrated for verification. The major contributions of this research are: (1) developing a skeleton-based method to analyze the human motion; (2) using Hidden Markov Model (HMM) and posture patterns to describe the motion type.  相似文献   
32.
由于受到"艺术至上论"和"技术至上论"两种不良教学思想的影响,使得我国高校服装设计教育出现毕业学生综合素质较差,学生知识结构单一,设计思路狭窄,与社会实际需求脱节现象严重等等弊端,我们要不断深刻反思,加以改进。  相似文献   
33.
浙江石窗是第二批浙江省非物质文化遗产名录中的一项民间美术,它是盛开在浙江大地上的一朵建筑民俗之花,它的审美趣味与当地的民风民俗和建筑风格完全融合,它的表现手法与中国的吉祥图案一脉相连。  相似文献   
34.
Examined V. Axlines's book, Play Therapy (1947) which includes 8 basic principles on non-directive play therapy. Student responses to learning these principles in play therapy classes were also examined. Each student was assigned a play therapy client and was observed and assisted directly by the instructor, a licensed clinical psychologist. Clients were mildly trouble children (aged 5–10 yrs) and were selected from a referral base by the instructor as appropriate for the course. As the semester progressed and students gained direct experience, weekly small (3–4 student) group discussions were held to explore in-depth understanding of play therapy principles and how these principles are put into practice. It is concluded that Axline's book remains a classic text and a foremost resource in the field. Coupling it with experiential learning is an invaluable basis for teaching play therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
35.
The confused world of sulfate attack on concrete   总被引:13,自引:0,他引:13  
External sulfate attack is not completely understood. Part I identifies the issues involved, pointing out disagreements, and distinguishes between the mere occurrence of chemical reactions of sulfates with hydrated cement paste and the damage or deterioration of concrete; only the latter are taken to represent sulfate attack. Furthermore, sulfate attack is defined as deleterious action involving sulfate ions; if the reaction is physical, then, it is physical sulfate attack that takes place. The discussion of the two forms of sulfate attack leads to a recommendation for distinct nomenclature. Sulfate attack on concrete structures in service is not widespread, and the amount of laboratory-based research seems to be disproportionately large. The mechanisms of attack by different sulfates—sodium, calcium, and magnesium—are discussed, including the issue of topochemical and through-solution reactions. The specific aspects of the action of magnesium sulfate are discussed, and the differences between laboratory conditions and field exposure are pointed out.Part II discusses the progress of sulfate attack and its manifestations. This is followed by a discussion of making sulfate-resisting concrete. One of the measures is to use Type V cement, and this topic is extensively discussed. Likewise, the influence of w/c on sulfate resistance is considered. The two parameters are not independent of one another. Moreover, the cation in the sulfate salt has a strong bearing on the efficiency of the Type V cement. Recent interpretations of the Bureau of Reclamation tests, both long term and accelerated, are evaluated, and it appears that they need reworking.Part III reviews the standards and guides for the classification of the severity of exposure of structures to sulfates and points out the lack of calibration of the various classes of exposure. A particular problem is the classification of soils because much depends on the extraction ratio of sulfate in the soil: there is a need for a standardized approach. Taking soil samples is discussed, with particular reference to interpreting highly variable contents of sulfates. The consequences of disturbed drainage of the soil adjacent to foundations and of excessive irrigation, coupled with the use of fertilizer, are described. Whether concrete has undergone sulfate attack can be established by determining the change in the compressive strength since the time of placing the concrete. The rejection of this method and the reliance on determining the tensile strength of concrete because of “layered damage” are erroneous. Scanning electron microscopy (SEM) should not be the primary, and certainly not the first, method of determining whether sulfate attack has occurred. Mathematical modeling will be of help in the future but, at present, cannot provide guidance on the sulfate resistance of concrete in structures.Part IV presents conclusions and an overview of the situation, with consideration of future improvements. Appendix A contains the classification of exposure to sulfate given by various codes and guides.  相似文献   
36.
37.
Based on the multiphase poroelasticity theory describing the propagation of waves in the unsaturated fluid-saturated porous medium, the reflection and transmission coefficients of the seismic waves at the interface between soil layers with different saturations are obtained. Our unsaturated model consists of a deformable skeleton in which two compressible and viscous fluids (i.e., water and gas) flow in the interstices. Three compressional waves (i.e., P1, P2, and P3 waves) and one shear (i.e., S wave) wave exist in the unsaturated soils. The expressions for the energy ratios of the various reflected and transmitted waves at the interface during the transmission and reflection processes are presented in explicit forms accordingly. At last, numerical computations are performed and the results obtained are respectively depicted graphically. The variation of the energy ratios with the incident angle, wave frequency and saturation degrees of the upper and lower soil layers is illustrated in detail. The calculation results show that the allocation of incident seismic waves at the interface is influenced not only by the angle and frequency of the incident seismic waves, but also by the saturations of the upper and lower soil layers. It is also verified that, at the interface, the sum of energy ratios of the reflected and transmitted waves is approximately equal to unity as was expected. This study is of importance to several fields such as geotechnical engineering, seismology, and geophysics.  相似文献   
38.
运用文献资料、访谈、问卷调查、数理统计等研究方法,对安徽省城镇体育人口现状进行调查研究,结果显示:安徽省经济发展迅速,社会体育人口比率与城镇居民人均可支配收入成正比,与各地市人口总数成反比。安徽省城镇体育人口性别比为109.55,分别高出全国和安徽省人口性别比4.35和6.16。  相似文献   
39.
通过对石墨化炉的特点及其供电方面的有关问题的分析,论述了石墨化炉供电的特点及其发展的趋势,并对石墨化炉在交、直流电源供电方面提出了看法,以不断提高石墨化炉供电的设计水平.  相似文献   
40.
可再生能源需要性能优良的储能电池与之配套,因此,研究和开发价廉、高效率的储能系统是十分必要的。本文通过介绍钒氧化还原液流电池的原理和特点,指出钒电池是一种潜力巨大的新型环保储能电池。同时介绍钒电池制备和应用时的三大技术关键及一定的解决方法。  相似文献   
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