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131.
自然主义对许多艺术门类都产生过深刻影响,在设计领域中,以自然主义为主要特点的新艺术运动曾在一个重大的设计变革时期——工业革命后风靡各国,然而却又在短短十多年后沉寂下来,本文主要分析自然主义为什么会在设计史的重要阶段产生如此特别的表现。 相似文献
132.
Dong RG Welcome DE Wu JZ 《Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine》2007,221(8):847-861
This study generally hypothesized that the vibration-induced biodynamic stress and number of its cycles in a substructure of the hand-arm system play an important role in the development of vibration-induced disorders in the substructure. As the first step to test this hypothesis, the specific aims of this study were to develop a practical method to quantify the biodynamic stress-cycle measure, to compare it with ISO-weighted and unweighted accelerations, and to assess its potential for applications. A mechanical-equivalent model of the system was established using reported experimental data. The model was used to estimate the average stresses in the fingers and palm. The frequency weightings of the stresses in these substructures were derived using the proposed stress-cycle measure. This study found the frequency dependence of the average stress distributed in the fingers is different from that in the palm. Therefore, this study predicted that the frequency dependencies of finger disorders could also be different from those of the disorders in the palm, wrist, and arms. If vibration-induced white finger (VWF) is correlated better with unweighted acceleration than with ISO-weighted acceleration, the biodynamic stress distributed in the fingers is likely to play a more important role in the development of VWF than is th e biodynamic stressdistributed in the other substructures of the hand-arm system. The results of this study also suggest that the ISO weighting underestimates the high-frequency effect on the finger disorder development but it may provide a reasonable risk assessment of the disorders in the wrist and arm. 相似文献
133.
《化学反应工程》多媒体课件的开发及应用 总被引:17,自引:11,他引:6
本文介绍用VB语言开发《化学反应工程》多媒体课件的性能特点,讨论实现中的一些主要技术及课件的使用情况。 相似文献
134.
Beta brass single crystal, bicrystal and tricrystal stress strain behavior were determined for a series of isoaxial specimens
in which the bicrystals and tricrystals were incompatible in shear along the grain boundary. Volume fractions of grain boundary
deformation were also determined to ascertain the effect of increased constraint on grain boundary strengthening. It was found
that bicrystal flow stress was considerably higher than single crystal flow stress and that tricrystal strain hardening was
only slightly larger than that of the bicrystal. For the tricrystals the grain boundary deformation zone is larger than that
of corresponding bicrystals because of both configurational and constraint effects. This larger zone indicates that secondary
stresses extend further from the boundary in tricrystals than in bicrystals. It was concluded that despite increased constraint,
, the average grain boundary stress for the tricrystals, is smaller than that for corresponding bicrystals and that because
of the increased extent of the secondary stress,σ
b
i, the stress in the center component away from the grain boundary, is higher than that of the single crystal at corresponding
strains. The relationship of these observations to corresponding stresses in polycrystalline material is examined.
where Taek Dong Lee was formerly a Graduate Student.
This paper is based on a thesis to be submitted by Taek Dong Lee in partial fulfillment of the requirements for the degree
of Doctor of Philosophy at Polytechnic Institute of New York. 相似文献
135.
介绍了清江隔河岩水电站火灾自动报警监控系统的设计思路、系统构成及使用方法,系统运行模式设计先进、完整、功能齐全,特别是设计的消防联动控制,使整个系统安全运行更有保证,该设计对其他生产单位特别是水电厂具有借鉴和指导意义。 相似文献
136.
空载投入变压器,从低压侧加压,高压侧相电压出现不平衡;而从高压侧加压,低压侧出现相电压不平衡,两种状态下线电压均平衡。此现象是什么原因造成,能否投入运行?是否影响发电机并列?就空载变压器投运电压不平衡问题进行探讨,得出在变压器各种试验满足规程要求的前提下,测得空载变压器线电压平衡,用户可以放心使用,对电气设备和发电机并列不会有什么影响。 相似文献
137.
简述了色彩形成的物理过程,建立一较有效的材料光谱特性仿真与色彩预测模型.采用密度泛函理论,计算了纤锌矿ZnO的复折射率,计算结果与实验结果相符.计算并分析了ZnO薄膜的反射光谱性质,预测了ZnO薄膜颜色为黄色,与实际样品相符.研究了薄膜厚度对ZnO薄膜色彩的影响,结果表明,在相干长度范围内(<1300 nm),膜厚对ZnO薄膜颜色调制作用显著,膜较厚时(>1300 nm),色彩及明度趋于稳定. 相似文献
138.
介绍了大气污染控制工程课程教学改革研究的内容,提出了由教学内容、教学形式、教学平台与教学评价等4方面组成的立体化课程教学模式,并讨论了该模式下教学资源平台的建设,给出了大气污染控制工程课程的评价和考核方法.该模式在实践教学中取得了比较好的成效. 相似文献
139.
对上海市地铁列车中的三种不同车型的微机控制系统的总线进行分析与研究,并针对近年总线通信中出现的问题,提出改进方法。 相似文献
140.
Facial expression recognition using radial encoding of local Gabor features and classifier synthesis
Primarily motivated by some characteristics of the human visual cortex (HVC), we propose a new facial expression recognition scheme, involving a statistical synthesis of hierarchical classifiers. In this scheme, the input images of the database are first subjected to local, multi-scale Gabor-filter operations, and then the resulting Gabor decompositions are encoded using radial grids, imitating the topographical map-structure of the HVC. The codes are fed to local classifiers to produce global features, representing facial expressions. Experimental results show that such a hybrid combination of the HVC structure with a hierarchical classifier significantly improves expression recognition accuracy when applied to wide-ranging databases in comparison with the results in the literature. Furthermore, the proposed system is not only robust to corrupted data and missing information, but can also be generalized to cross-database expression recognition. 相似文献