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轧制过程中的板型分析 被引量:1
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作者 王文高 刘煜 《铝加工》 CAS 1994年第5期31-33,30,共4页
本文介绍了铝板带箔材轧制过程中板型缺陷产生的机理、保持板型平直度的条件、离线板型的影响因素和各种板型缺陷产生的原因.
关键词 分析 平直度 线板型 铝材 轧制
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脉冲电晕脱硫脱硝反应器电极配置研究 被引量:7
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作者 李国锋 吴彦 王宁会 《大连理工大学学报》 EI CAS CSCD 北大核心 1999年第1期39-42,共4页
从放电极配置的角度研究了脉冲电晕法烟气脱硫脱硝的关键技术之一能量注入问题.在线板型反应器上实验得到以下主要结果:(1)脉冲成形电容决定了高压纳秒脉冲宽度,放电极邻距在一定范围内的变化对脉冲宽度及脉冲上升前沿的影响可以... 从放电极配置的角度研究了脉冲电晕法烟气脱硫脱硝的关键技术之一能量注入问题.在线板型反应器上实验得到以下主要结果:(1)脉冲成形电容决定了高压纳秒脉冲宽度,放电极邻距在一定范围内的变化对脉冲宽度及脉冲上升前沿的影响可以忽略.(2)放电极邻距在保证不产生火花放电的情况下可以加到最密;这样脉冲成形电容的值可调整范围大,可以通过调整脉冲宽度达到多注入反应器能量的目的.(3)放电极密的时候(本实验为邻距50mm),同其他邻距形式对比,反应器内等离子体通道更为均匀,有利于SO2和NOx的脱除. 展开更多
关键词 脱硫 脱硝 脉冲电晕 反应器 烟气 电极 线板型
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一起500kV变电站跨路管母脱落原因分析及改进措施 被引量:1
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作者 苏文宇 徐珍 黄斌 《江西电力职业技术学院学报》 CAS 2012年第2期4-6,9,共4页
分析了一起500 kV变电站U型接线板断裂造成跳闸事故的原因,并提出了改进措施,以防止同类事故的发生。
关键词 跳闸 U线板 断裂
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Construction and solution of strain model along thickness of aluminum alloy plate under plastic deformation
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作者 张舒原 廖凯 吴运新 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第10期3381-3388,共8页
A thickness strain model of aluminium alloy plate under plastic deformation,based on thin plate assumption was proposed.It is found that when ratio of stress fractions is constant during in-plane loading,ratios of str... A thickness strain model of aluminium alloy plate under plastic deformation,based on thin plate assumption was proposed.It is found that when ratio of stress fractions is constant during in-plane loading,ratios of strain components under various loading conditions are linearly related and these points of ratios form a η-η line.Under these simple loadings,strains in thickness direction can be easily calculated by the η-η line equation without integral and differential work.When the plate is under more complicated loading conditions,the thickness can be computed by the proposed optimization and piecewise calculation model.Validation computations indicate that the relative error of the results of the presented model is less than 0.75% compared with the proven theories and FE simulation.Therefore,the developed model can be applied to engineering calculation,e.g.pre-stretching analysis of aerospace aluminium thick plate,with acceptable accuracy. 展开更多
关键词 isotropic linear hardening thick plate strain model plastic deformation aluminum alloy
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The effect of mining face's direction on the observed seismic activity 被引量:8
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作者 Witold Pytel Joanna Switon Adrian Wojcik 《International Journal of Coal Science & Technology》 EI 2016年第3期322-329,共8页
A major natural hazard associated with LGOM (Legnica-Glogow Copper Mining) mining is the dynamic phenomena occurrence, physically observed as seismic tremors. Some of them generate effects in the form of relaxations... A major natural hazard associated with LGOM (Legnica-Glogow Copper Mining) mining is the dynamic phenomena occurrence, physically observed as seismic tremors. Some of them generate effects in the form of relaxations or bumps. Long-term observations of the rock mass behaviour indicate that the degree of seismic hazard, and therefore also seismic activity in the LGOM area, is affected by the great depth of the copper deposit, high-strength rocks as well as the ability of rock mass to accumulate elastic energy. In this aspect, the effect of the characteristics of initial stress tensor and the orientation of considered mining panel in regards to its components must be emphasised. The primary objective of this study is to answer the question, which of the factors considered as "influencing" the dynamic phenomena occurrence in copper mines have a statistically significant effect on seismic activity and to what extent. Using the general linear model procedure, an attempt has been made to quantify the impact of different parameters, including the depth of deposit, the presence of goaf in the vicinity of operating mining panels and the direction of mining face advance, on seismic activity based on historical data from 2000 to 2010 concerned with the dynamic phenomena recorded in different mining panels in Rudna mine. The direction of mining face advance as well as the goaf situation in the vicinity of the mining panel are of the greatest interest in the case of the seismic activity in LGOM. It can be assumed that the appropriate manipulation of parameters of mining systems should ensure the safest variant of mining method under specific geological and mining conditions. 展开更多
关键词 Induced seismicity Polish copper mines General linear model procedure
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Board of Directors, Independent Directors and Audit Fees: Based on the Empirical Data of the GEM of China
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作者 HAN Zhenguo YANG Guang 《International Journal of Technology Management》 2014年第6期116-121,共6页
As one of the alternative variables of audit quality, audit fees have been researched widely in the Mainboard of China stock market, but empirical research based on the GEM (Growth Enterprise Market) of China is ver... As one of the alternative variables of audit quality, audit fees have been researched widely in the Mainboard of China stock market, but empirical research based on the GEM (Growth Enterprise Market) of China is very few. From the perspective of GEM of China, this article observes and studies the impact of corporate governance structure represented by board of directors and independent directors on audit fees. This article selects the data of 348 listed companies in the GEM of China in 2012, proves that there is a positive correlation between the number of meetings, independent directors' salaries and audit fees through the use of multiple linear regression model, and accordingly proposed suggestions that improve the corporate governance structure of the GEM of China. 展开更多
关键词 GEM of China Board of Directors Independent Directors Audit Fees
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Full-scale model tests and nonlinear analysis of prestressed concrete simply supported box girders
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作者 Fang Zhi Tang Shenghua He Xin 《Engineering Sciences》 EI 2014年第1期67-76,共10页
Full-scale model tests were carried out on a 30 m span prestressed concrete box girder and a 20 m span prestressed concrete hollow slab. Failure models were prestressed reinforcement tensile failure and crashing of ro... Full-scale model tests were carried out on a 30 m span prestressed concrete box girder and a 20 m span prestressed concrete hollow slab. Failure models were prestressed reinforcement tensile failure and crashing of roof concrete, respectively. The ductility indexes of the box girder and hollow slab were 1.99 and 1.23, respectively, according to the energy viewpoint. Based on the horizontal section hypothesis, the nonlinear computation procedure was established using the limited banding law, and it could carry out the entire performance analysis including the unloading, mainly focusing on the ways to achieve the unloading curves computation through stress-strain, moment-curvature and load-displacement curves. Through the procedure, parameters that influence on the bearing capacity, deformation performance and ductility of the structures were analyzed. Those parameters were quantity of prestressed reinforcement and tension coefficients of prestressed reinforcement. From the analysis, some useful conclusions can be obtained. 展开更多
关键词 prestressed concrete box girder full-scale model test nonlinear analysis bearing capacity DUCTILITY
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Numerical investigation on the aerodynamic drag reduction based on bottom deflectors and streamlined bogies of a high-speed train
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作者 JIANG Chen LONG jn-lan +2 位作者 LI Yan-ong GAO Guang-jun FRANKLIN Eze 《Journal of Central South University》 SCIE EI CAS 2024年第9期3312-3328,共17页
The complex structure of the bottom of a high-speed train is an important source of train aerodynamic drag.Thus,improving the bottom structure is of great significance to reduce the aerodynamic drag of the train.In th... The complex structure of the bottom of a high-speed train is an important source of train aerodynamic drag.Thus,improving the bottom structure is of great significance to reduce the aerodynamic drag of the train.In this study,computational fluid dynamics(CFD)based on three-dimensional steady incompressible Reynolds-average Naiver-Stokes(RANS)equations and Realizable k-ε turbulence model were utilized for numerical simulations.Inspired by the concept of streamlined design and the idea of bottom flow field control,this study iteratively designed the bogies in a streamlined shape and combined them with the bottom deflectors to investigate the joint drag reduction mechanism.Three models,i.e.,single-bogie model,simplified train model,and eight-car high-speed train model,were created and their aerodynamic characteristics were analyzed.The results show that the single-bogie model with streamlined design shows a noticeable drag reduction,whose power bogie and trailer bogie experience 13.92%and 7.63%drag reduction,respectively.The range of positive pressure area on the bogie is reduced.The aerodynamic drag can be further reduced to 15.01%by installing both the streamlined bogie and the deflector on the simplified train model.When the streamlined bogies and deflectors are used on the eight-car model together,the total drag reduction rate reaches 2.90%.Therefore,the proposed aerodynamic kit for the high-speed train bottom is capable to improve the flow structure around the bogie regions,reduce the bottom flow velocity,and narrow the scope of the train’s influence on the surrounding environment,achieving the appreciable reduction of aerodynamic drag.This paper can provide a new idea for the drag reduction of high-speed trains. 展开更多
关键词 high-speed train numerical simulation drag reduction deflector streamlined design
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彩涂机组的新工艺
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作者 周小舟 徐燕萍 《涂装指南》 2005年第3期47-52,共6页
在未来的10年里,我国的彩涂钢板市场将越来越好,可发展的空间很大,但是随着国际市场一体化程度越来越高,竞争也将越来越激烈。因此,推广彩涂新工艺,开发彩涂钢板的新品种,提高产品的技术含量和附加值是我们面临的一项急待研究和... 在未来的10年里,我国的彩涂钢板市场将越来越好,可发展的空间很大,但是随着国际市场一体化程度越来越高,竞争也将越来越激烈。因此,推广彩涂新工艺,开发彩涂钢板的新品种,提高产品的技术含量和附加值是我们面临的一项急待研究和攻关的难题。周小舟,徐燕萍两位作者在本文中介绍了彩色涂层钢板新工艺的发展趋,并且重点介绍了涂层闭环控制系统,焚烧炉系统,在线板型控制等最先进的工艺。 展开更多
关键词 彩涂机组 涂装工艺 彩涂钢板 技术含量 涂层闭环控制系统 焚烧炉系统 线板型控制
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Weighted Profile Least Squares Estimation for a Panel Data Varying-Coefficient Partially Linear Model
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作者 Bin ZHOU Jinhong YOU +1 位作者 Qinfeng XU Gemai CHEN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2010年第2期247-272,共26页
This paper is concerned with inference of panel data varying-coefficient partially linear models with a one-way error structure. The model is a natural extension of the well-known panel data linear model (due to Balt... This paper is concerned with inference of panel data varying-coefficient partially linear models with a one-way error structure. The model is a natural extension of the well-known panel data linear model (due to Baltagi 1995) to the setting of semiparametric regressions. The authors propose a weighted profile least squares estimator (WPLSE) and a weighted local polynomial estimator (WLPE) for the parametric and nonparametric components, respectively. It is shown that the WPLSE is asymptotically more efficient than the usual profile least squares estimator (PLSE), and that the WLPE is also asymptotically more efficient than the usual local polynomial estimator (LPE). The latter is an interesting result. According to Ruckstuhl, Welsh and Carroll (2000) and Lin and Carroll (2000), ignoring the correlation structure entirely and "pretending" that the data are really independent will result in more efficient estimators when estimating nonparametric regression with longitudinal or panel data. The result in this paper shows that this is not true when the design points of the nonparametric component have a closeness property within groups. The asymptotic properties of the proposed weighted estimators are derived. In addition, a block bootstrap test is proposed for the goodness of fit of models, which can accommodate the correlations within groups illustrate the finite sample performances of the Some simulation studies are conducted to proposed procedures. 展开更多
关键词 SEMIPARAMETRIC Panel data Local polynomial Weighted estimation Block bootstrap
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