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101.
用物元可拓方法和反映洪水灾害灾度的指标以及层次分析法相结合,建立了水灾灾度定量综合评价模型.利用该模型对山东地区的水灾进行了灾度定量综合评价,结果表明不仅提高了水灾的定量化水平和精确程度,而且使水灾灾度定量评价更加综合和深入. 相似文献
102.
Abstract This paper investigates the characteristics of acoustic emission (AE) signals generated from hydrogen induced cracking (HIC) and sulfide stress corrosion cracking (SSCC) for a medium strength steel in hydrogen sulfide (H2S) solution. The experiments performed in this study include the constant load test (CLT) and the constant extension rate test (CERT). From the results of the CLT, the AE count rate caused by SSCC was found to be much higher than that resulted from the HIC; and the increase of the AE count rate was observed to be approximately proportional to the increase of the applied loading. In addition, the AE frequency distribution diagrams obtained from these tests were found to contain potential information for distinguishing the mechanisms of HIC and SSCC. From the results of CERT, the AE signals detected from the specimens tested in the H2S solution were compared with those obtained from the specimens tested in the air. In addition, the AE count rate detected from the tensile specimens was studied according to the different deformation stages of the specimens. From this study, the variation of the AE count rate in each deformation stage was described. 相似文献
103.
本文建立了旋转类采样机包含皮带中部采样机、旋斗采样机、旋转缩分机、旋管缩分机的通用数学模型,推导了截取料流时的轨迹方程、速度方程、最大速度波动公式、最大面积波动公式,从数学分析角度阐述了粒度偏析机理,找到了减少粒度偏析及提高采样精度的有效途径。 相似文献
104.
Electrical disintegration is an effective liberation technique in mineral processing where the liberation ratio depends on the mineralogical properties of the mineral grains. However elucidation of the liberation behavior is difficult since the fragments after the electrical disintegration are fine and complex. This study applies electrical disintegration to cement paste samples with various dispersed mineral particles (calcite, quartz, albite, and pyrite) and the disintegrated products are observed with a micro-focus X-ray CT scanner. Current channels and crack extension behavior from the channels are identified by cross sectional CT and three dimensional reconstructed images. A classification of the crack patterns was carried out and compared with the results of liberation ratio measurements of the products. 相似文献
105.
HAROLD W. LEWIS III 《国际通用系统杂志》2013,42(1-2):97-114
Abstract On the subject of fuzzy set-based approximate reasoning, this paper attempts to present a perspective that is both rigorously stated and different from the standard approach as stated by Mamdani and many others. Functionally speaking, this alternative perspective produces results essentially the same as the standard one, and in fact we intend to prove that subject to certain assumptions the results will be exactly die same. We feel however that the alternative perspective offers advantages in that it makes a more appropriate and more understandable use of such concepts as fuzzy relations, the extension principle, and fuzzy composition. If indeed it can lead to a clearer and more widespread understanding of the approximate reasoning formalism then this could conceivably spark broader interest in fuzzy control and other applications. 相似文献
106.
针对铁路客车上水栓的现状及特点,设计出一套客车水栓压力在线监测及故障自动切除系统,并分析了使用该系统的必要性,介绍了该系统可实现的功能,对该系统的关键技术及监控组态软件设计作了详细论述,以促进其推广应用。 相似文献
107.
Meng‐Hui Wang Pi‐Chu Wu Wei‐Jhe Jiang 《IEEJ Transactions on Electrical and Electronic Engineering》2015,10(4):479-486
Distribution panels are an important piece of equipment in power systems. Maintaining a loading panel and ensuring security are not easy because the power supply cannot be interrupted in high‐tech factories. Distribution panels need fully functional condition monitoring and fault diagnosis systems to prevent accidents and reduce maintenance costs. In this paper, a new scheme is proposed to design an auto‐diagnosis tool for electrical distribution panels using infrared thermography to build diagnostic features using the matter‐element model. The paper then presents an extension recognize method (ERM) based on extension theory to diagnose the abnormality element by using degrees of correlation between the tested pattern and the matter‐element models that have been built up. Test results show that the proposed method can not only recognize the main defect element of the tested panel but also detect useful information for future trends and multi‐defect analysis by the correlation indexes. This new approach merits more attention as a tool to be used in the defect recognition problems of distribution panels, especially in high‐tech factories in Taiwan. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
108.
Yan-Bin Gao 《Soils and Foundations》2013,53(3):431-442
A series of undrained and drained triaxial tests were conducted to investigate the yielding behavior of anisotropically consolidated reconstituted Shanghai clay under triaxial compression and extension loading conditions. The soil was consolidated with K of 0.5, where K is the ratio of cell pressure to axial pressure. The tests included drained constant η (=q/p′) loading tests and undrained and drained triaxial compression and extension shear tests on anisotropically consolidated specimens. It was found that the anisotropically consolidated Shanghai clay obeys Rendulic’s principle under compression loading, but not under extension loading, and that the yield surface inclined inside the state boundary surface under extension loading. Moreover, the pre-yield behavior and the post-yield behavior were found to be very different under these two loading conditions (compression and extension loading). The test results confirm the validity of the sloping elastic wall theory, and the influence of anisotropic parameter β on the shape of the yield curve in the p′?v plane was also studied in the paper. Constitutive modeling methods for anisotropic consolidated soils were also discussed based on the test results. 相似文献
109.
110.
This paper describes a bridge condition assessment model that is based upon the simplification of a computational technique called resolution identity of fuzzy sets. The proposed model utilizes a fuzzy weighted average to combine fuzzy bridge condition ratings. The procedure is based on the decomposition of fuzzy sets into non-fuzzy level-sets or intervals. The utility and effectiveness of this procedure are illustrated with an example of the bridge condition assessment problem. 相似文献