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991.
(1)本文引入仿射变换,提出了一种用矩算子以民分辨率图象直接进行边界检测的方法,利用同分辨率图象正方形窗口的模板行矩的计算,推导出了相应用的边界参数公式。(2)本文提出一种隐线笥插值矩计算方法,得到一组与正方形窗口对应的正方形模板,避免了费时的预插值过程,(3)对本文提出的方法进行了实验验证,并给出了实验结果。 相似文献
992.
993.
A new method is described for spectroscopic diagnostics of combustion and explosion products, which makes it possible to study
processes occurring at short times in hot and dense molecular gases.
Pis’ma Zh. Tekh. Fiz. 23, 16–19 (March 26, 1997) 相似文献
994.
In this paper, a mixed approach for probabilistic structural durability design of mechanical systems is proposed. In this approach, a deterministic design optimization that considers structural crack initiation and crack propagation lives at critical points of the structural component as design constraints is performed first. After an optimal design is obtained, a reliability analysis is performed to ascertain if the deterministic optimal design is reliable. If the probability of the failure of the deterministic optimal design is found to be acceptable, a reliability-based design approach that employs a set of interactive design steps, such as trade-off analysis and what-if study, is used to obtain a near-optimal design that is reliable with an affordable computational cost. A 3-D tracked vehicle roadarm is employed to demonstrate the feasibility of the proposed approach. 相似文献
995.
996.
也谈轻型钢结构房屋柱基设计 总被引:1,自引:1,他引:0
对柱脚抗剪键的设置和计算中所取用的荷载组合提出个人观点,同时对轻钢结构柱脚螺栓受拉计算提出注意事项. 相似文献
997.
Yu. N. Zayko 《Technical Physics Letters》2006,32(11):972-974
The transmission capacity of a nonlinear classical communications channel that does not obey the well-known Shannon formula describing a linear additive channel is analyzed. According to the Landauer principle, no finite energy is required to transmit a bit of information, which, in principle, makes reversible data transmission possible. The process of data transmission is analyzed using a model of the transmitting medium representing a ferroelectric crystal possessing a center of symmetry. Using this model, it is possible to trace an analogy between the process of bit setting and transmission, on the one hand, and the violation of the lattice symmetry as a result of the second-order phase transition at the Curie temperature, on the other hand. An expression for the transmission capacity is obtained using the well-known cnoidal solution of the corresponding nonlinear equations in the absence of damping. The transmission capacity of an arbitrary nonlinear classical communication channel is estimated. 相似文献
998.
S. A. Kotrechko Yu. Ya. Meshkov R. V. Televich 《Metal Science and Heat Treatment》2006,48(9-10):405-411
Results of experimental and theoretical studies of the effect of the size of martensite laths and carbide particles on the value of the minimum stress of brittle fracture (brittle strength) of steel 12KhN3MFA subjected to uniaxial extension are presented. The critical proportion of the sizes of carbide particles and martensite laths is determined at which the microstructural component that controls the level of the brittle strength changes. Quantitative dependences for predicting the effect of the nonuniformity of the grain structure on the brittle strength of martensitic steels are obtained. Parameters of the microstructure, which make it possible to raise the brittle strength of low-carbon martensitic steels, are determined and the efficiency of rapid heat treatment for creating such structural states is demonstrated. 相似文献
999.
将金属铜易与过氧化物发生氧化还原反应生成游离基的原理应用于厌氧胶,开发了针时金属零件表面微孔进行局部渗补的实用技术。在相关技术可靠性和工艺可行性得以论证的前提下。将局部渗补技术成功地应用于渗补发动机泄漏缸盖,减少了废品损失,取得了良好的经济效益。 相似文献
1000.
The effect of an external harmonic signal on the characteristics of microwave generation in a non-relativistic electron beam with virtual cathode (VC) formed in a static retarding electric field (low-voltage vircator system) has been experimentally studied. A significant increase in the vircator generation power is observed when the frequency of the external signal is close to the frequency of VC oscillations. At large detunings, a broadband chaotic generation is observed. 相似文献