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171.
高炉冷却技术的开发与应用 总被引:1,自引:0,他引:1
通过对中小型高型炉寿命的分析,结合河北省冶金设计院高炉设计的实践经验,总结了高炉冷却设备寿命短的原因,并提出冷却设备在材质和结构上的改进措施。 相似文献
172.
Zheng Liu Zhiyun Xue Rick S. Blum Robert Laganière 《Pattern Analysis & Applications》2006,8(4):375-389
Images acquired by heterogeneous image sensors may provide complementary information about the scene, for instance, the visual image can provide personal identification information like the facial pattern while the infrared (IR) or millimeter wave image can detect the suspicious regions of concealed weapons. Usually, a technique, namely multiresolution pixel-level image fusion is applied to integrate the information from multi-sensor images. However, when the images are significantly different, the performance of the multiresolution fusion algorithms is not always satisfactory. In this study, a new strategy consisting of two steps is proposed. The first step is to use an unsupervised fuzzy k-means clustering to detect the concealed weapon from the IR image. The detected region is embedded in the visual image in the second step and this process is implemented with a multiresolution mosaic technique. Therefore, the synthesized image retains the quality comparable to the visual image while the region of the concealed weapon is highlighted and enhanced. The experimental results indicate the efficiency of the proposed approach.This material is based on part of the work carried out at the SPCR laboratory of Lehigh University and the work is partially supported by the U. S. Army Research Office under grant number DAAD19-00-1-0431. The content of the information does not necessarily reflect the position or the policy of the federal government, and no official endorsement should be inferred. 相似文献
173.
174.
Gillespie J.K. Fitch R.C. Sewell J. Dettmer R. Via G.D. Crespo A. Jenkins T.J. Luo B. Mehandru R. Kim J. Ren F. Gila B.P. Onstine A.H. Abernathy C.R. Pearton S.J. 《Electron Device Letters, IEEE》2002,23(9):505-507
The low temperature (100°C) deposition of Sc2O3 or MgO layers is found to significantly increase the output power of AlGaN/GaN HEMTs. At 4 GHz, there was a better than 3 dB increase in output power of 0.5×100 μm2 HEMTs for both types of oxide passivation layers. Both Sc2 O3 and MgO produced larger output power increases at 4 GHz than conventional plasma-enhanced chemical vapor deposited (PECVD) SiNx passivation which typically showed ⩽2 dB increase on the same types of devices. The HEMT gain also in general remained linear over a wider input power range with the Sc2O3 or MgO passivation. These films appear promising for reducing the effects of surface states on the DC and RF performance of AlGaN/GaN HEMTs 相似文献
175.
Comparisons of Urban Travel Forecasts Prepared with the Sequential Procedure and a Combined Model 总被引:4,自引:1,他引:3
Justin D. Siegel Joaquín De Cea José Enrique Fernández Renán E. Rodriguez David Boyce 《Networks and Spatial Economics》2006,6(2):135-148
Detailed analyses and comparisons of urban travel forecasts prepared by applying the state-of-practice sequential procedure
and the solution of a combined network equilibrium model are presented. The sequential procedure for solving the trip distribution,
mode choice and assignment problems with feedback is the current practice in most transportation planning agencies, although
its important limitations are well known. The solution of a combined model, in contrast, results from a single mathematical
formulation, which ensures a well-converged and consistent result. Using a real network, several methods for solving the sequential
procedure with feedback are compared to the solution of the combined model ESTRAUS. The results of these methods are shown
to have various levels of instability. The paper concludes with a call for a new paradigm of travel forecasting practice based
on an internally consistent model formulation that can be solved to a level of precision suitable for comparing alternative
scenarios. 相似文献
176.
Quantitatively describing the signal transduction process is important for understanding the mechanism of signal regulation
in cells, and thus, poses both a challenge and an opportunity for chemical and biochemical engineers. An artificial neural
network (ANN), in which we took the signal molecules as neural nodes, was constructed to simulate the generation of active
oxygen species (AOS) in Taxus chinensis cells induced by a bio-elicitor. The relative contents of AOS in cells predicted by the ANN model agreed well with the experimental
data and three notable stages of AOS increase were observed from the 3D figure of AOS generation. The robustness of AOS trajectories
indicated that signal regulation in vivo was an integral feedback control model that ensured the adaptation of Taxus chinensis to environmental stress. The artificial neural network was able to predict taxol production as well as determine the optimal
concentration of oligosaccharides needed for it. 相似文献
177.
178.
植被散射实验数据的特性分析 总被引:1,自引:0,他引:1
本文根据电波所获取的各种樾 射实测数据,分析了它们对不同极化波的响应特性。 相似文献
179.
A non-iterative identification method with parameterization of the unknown dead-zone is proposed for Hammerstein systems in presence of asymmetric dead-zone nonlinearities.The canonical parameterized model which is a single expression without segmentation is utilized to describe the dead-zone,based on which a universal-type parametric model can be established to approximate the entire system.This model can be established without separating the nonlinear part from the linear part.The dead-zone parameters and the coefficients in the linear transfer function can be estimated simultaneously according to the proposed algorithm.Numerical experiments are presented to illustrate the effectiveness of the proposed scheme. 相似文献
180.
随着江西省各级政府系统信息化建设的日益发展,现有的政务信息网视频会议系统陈旧落后,无法满足现阶段的工作要求。为满足各级党政机关的会议要求,引进最先进的网络高清视讯技术H.264,建设一套高清视频会议系统,具有重要意义。 相似文献