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51.
C. H. Shek J. K. L. Lai G. M. Lin Z. F. Tang 《Metallurgical and Materials Transactions A》1997,28(6):1337-1340
The fracture toughness J
Ic
(ρ) and fractal dimension D
f
of fractured surfaces of CuNiAl single crystal have been measured at temperatures in the range 20 °C to 120 °C, in which
thermoelastic martensitic transformation takes place. The parent phase has higher fracture toughness than the martensite phase
due to stress-induced transformation. The relationship between J
Ic
(ρ) and D
f
has been studied. It was found that log J
Ic
(ρ) is linearly related to D
f
if the failure involves a single mechanism. The slope of the plot may either be positive or negative for brittle or ductile
failure, respectively. The difference in the J
Ic
(ρ)-D
f
correlation can be understood in terms of the micromechanism of fracture. 相似文献
52.
本文给出了用加强板加大管道截面系数来增加架空输水管道跨越距离的设计方法及其计算过程,并用实例说明了用此种方法加强大跨度管道的有效性和合理性。 相似文献
53.
An approach to aid decision making for urban water management is presented that is based on the concept of trade-off sacrifice level in pairwise comparisons between criteria, modelled using fuzzy logic. This approach is illustrated by a case study - selection of alternative water supplies for a Sydney household. Four key decision making criteria covering health, economic, environment and technical aspects are selected: annual probability of infection, life cycle energy use, life cycle cost and reliability. The decision making problem is to select between cases with different volume and application of recycled greywater and rainwater in light of the four criteria. Decision maker's preference is expressed by five levels of trade-off sacrifice between pairs of criteria. The decision makers can assign their preferences for sacrifice level by linguistic assessment and the output trade-off weight (TOW). Measures of decision makers' perceived trade-off level are modelled by a rule-based fuzzy logic control system. The final analysis shows the performance for each sacrifice class for each case, to aid overall decision making with stakeholders. 相似文献
54.
H.C. Kuo Y.H. Chang H.H. Yao Y.A. Chang F.-I. Lai M.Y. Tsai S.C. Wang 《Photonics Technology Letters, IEEE》2005,17(3):528-530
1.27-/spl mu/m InGaAs: Sb-GaAs-GaAsP vertical-cavity surface-emitting lasers (VCSELs) were grown by metal-organic chemical vapor deposition and exhibited excellent performance and temperature stability. The threshold current changes from 1.8 to 1.1 mA and the slope efficiency falls less than /spl sim/35% as the temperature raised from room temperature to 70/spl deg/C. With a bias current of only 5 mA, the 3-dB modulation frequency response was measured to be 8.36 GHz, which is appropriate for 10-Gb/s operation. The maximal bandwidth is measured to be 10.7 GHz with modulation current efficiency factor (MCEF) of /spl sim/5.25 GHz/(mA)/sup 1/2/. These VCSELs also demonstrate high-speed modulation up to 10 Gb/s from 25/spl deg/C to 70/spl deg/C. 相似文献
55.
食品安全.在2005年中仍然纷纷扰扰:食品与家庭每个成员的健康息息相关,而维护全家人的健康,则是女主人义不容辞的责任。我们一起来听听.于她们而言.2005年最关心的食品安全问题是什么?[编者按] 相似文献
56.
对EDGE技术进行了介绍,并对EDGE技术的现网测试进行了说明,对于EDGE技术的功能特点及现网应用的模型、性能指标进行了研究和探讨。 相似文献
57.
CT Lai VA Tanay GA Rauw AN Bateson IL Martin GB Baker 《Canadian Metallurgical Quarterly》1997,704(1-2):175-179
Reported here is a rapid, sensitive and relatively inexpensive procedure using gas chromatography with nitrogen-phosphorus detection (GC-NPD) to quantify buspirone levels in brains of rats. The analyte was directly extracted from brain homogenate with toluene after basification and then subjected to GC-NPD analysis using a capillary column. The calibration curves were linear over the range of 10 to 320 ng per 2 ml of brain homogenate, with typical r2 values >0.99. The assay was highly reproducible and gave peaks with excellent chromatographic properties. 相似文献
58.
中国南海北部二氧化碳气成因 总被引:3,自引:0,他引:3
中国南海北部海域在油气勘探中发现了CO_2气,对油气有无影响?在借鉴世界、中国东部陆地CO_2气成因研究成果的基础上,从分析研究区CO_2,气的分布入手,采用多种方法,在综合分析基础上,对本区CO_2气藏进行分类.认为研究区CO_2;气藏为无机成因,其特征受各盆地或地区具体地质条件的控制.哈萨克斯坦引起了国际石油界的很大关注,但它并不是前苏联唯一的具吸引力之地.美国地质调查调查所(丹佛)和AAPG今年著名讲演者Gregory F Ulmishek说.前苏联有20多个沉积盆地生产油气或具有尚未开采的发现.Ulmishek 1980年到美国前,获得过莫斯科石油学院地质学硕士学位,作为一个地质学家在前苏联工作过23年.他的1993—1994年题为“前苏联主要油气地质学及勘探潜力”的著名演讲在1993年12月6日至17日和1994年3月28日至4月8日的巡回活动中推出. 相似文献
59.
Zhan Choujun Zheng Yufan Lai Zhikang Hao Tianyong Li Bing 《Neural computing & applications》2021,33(10):4915-4928
Neural Computing and Applications - At the end of 2019, a new coronavirus (COVID-19) epidemic has triggered global public health concern. Here, a model integrating the daily intercity migration... 相似文献
60.
Shilton A Lai DT Santhiranayagam BK Palaniswami M 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2012,42(3):950-955
This note presents an analysis of the octonionic form of the division algebraic support vector regressor (SVR) first introduced by Shilton A detailed derivation of the dual form is given, and three conditions under which it is analogous to the quaternionic case are exhibited. It is shown that, in the general case of an octonionic-valued feature map, the usual "kernel trick" breaks down. The cause of this (and its interpretation) is discussed in some detail, along with potential ways of extending kernel methods to take advantage of the distinct features present in the general case. Finally, the octonionic SVR is applied to an example gait analysis problem, and its performance is compared to that of the least squares SVR, the Clifford SVR, and the multidimensional SVR. 相似文献