检索结果-内蒙古大学图书馆

The second International Conference of Electrical and Electronics engineering(ICEEE 2011)

作者： Xu Feng Wu Qiang Zhu Lihua Key Lab.for the Exploitation of Southwestern Resources & the Environmental Disaster Control Engineering Ministry of Education Chongqing University School of Safety Engineering & Technology Heilongjiang Institute of Science & Technology

By using observation method, the dissociation process of methane hydrate at normal temperature and pressure is studied, and it is discovered which the dissociation of methane hydrate isn't occurred synchronously at whole surface, but heterogeneous characteristic of dissociation is emerged. The dissociation rate of hydrate is slow at normal temperature and pressure, and average dissociation rate is 2.15×10-4m3·h-1. The dissociation kinetic equation of methane hydrate is proposed. It is revealed that the dissociation of methane hydrate at normal pressure is a pseudo first-order reaction. The dissociation rate coefficient of methane hydrate in different time is calculated, and the result shows that the rate coefficient is relative to reaction time, namely the dissociation kinetics of methane hydrate does not tally with the typical kinetics law, and the dissociation reaction kinetics of methane hydrate is fractal-like. Lastly, the environment effent of hydrate dissociation is also analyzed.

关键词： methane hydrate,dissociation,fractal-like,environment

来源：评论

学校读者我要写书评

暂无评论

Quasi-Green’s function method for free vibration of simply-supported trapezoidal shallow spherical shell

引用

Applied Mathematics and Mechanics(English Edition) 2010年第5期31卷 635-642页

作者：李善倾袁鸿 Key Laboratory of Disaster Forecast and Control in Engineering Ministry of Education of China Institute of Applied Mechanics Jinan University

The idea of quasi-Green＇s function method is clarified by considering a free vibration problem of the simply-supported trapezoidal shallow spherical shell. A quasi- Green＇s function is established by using the fundamental solution and boundary equation of the problem. This function satisfies the homogeneous boundary condition of the prob- lem. The mode shape differential equations of the free vibration problem of a simply- supported trapezoidal shallow spherical shell are reduced to two simultaneous Fredholm integral equations of the second kind by the Green formula. There are multiple choices for the normalized boundary equation. Based on a chosen normalized boundary equa- tion, a new normalized boundary equation can be established such that the irregularity of the kernel of integral equations is overcome. Finally, natural frequency is obtained by the condition that there exists a nontrivial solution to the numerically discrete algebraic equations derived from the integral equations. Numerical results show high accuracy of the quasi-Green＇s function method.

关键词： Green function integral equation shallow spherical shell free vibration

来源：评论

学校读者我要写书评

暂无评论

Evaluation indexes of sand liquefaction analysed by rough set

引用

1st International Conference on Civil engineering, Architecture and Building Materials, CEABM 2011

作者： Liu, Nianping Wang, Hongtu Yuan, Zhigang Key Lab. for Exploitation of China Southwestern Resources and Environmental Disaster Control Eng. Chongqing University Ministry of Education Chongqing 400030 China State and Local Joint Engineering Laboratory of Methane Drainage in Complex Coal Gas Seam Chongqing University Chongqing 400030 China College of Environment and Resources Southwest University of Science and Technology Mianyang 621010 China

ISBN: (纸本)9783037851258

Sand liquefaction is a problem of complex evolution of the disaster, there is no accurate way to judge at present, this study put forward an analytical method to improve and optimize the evaluation system of sand liquefaction based on rough set. The significance of indexes are confirmed by calculating rough dependability between indexes and result for appraisement, the result show that SPT blow count has the greatest impact on the evaluation system, the groundwater level has greater impact, followed by the sand depth, epicenteral distance and duration. The proposed approach overcame the subjectivity of traditional weight determination method, so it is more objective and accurate, and it is reasonable and effective to optimize the evaluation index of sand liquefaction. © (2011) Trans Tech Publications.

关键词： Groundwater

来源：评论

学校读者我要写书评

暂无评论

Experimental Study of Different Gases on Permeability of Tectonic Coal

引用

Procedia engineering 2011年 26卷 1176-1183页

作者： Lei Meng Yaodong Jiang Jie Zhu Ang Li Weizhong Wang China University of Mining & Technology Beijing 100083 China State Key Lab of Coal Resources and Safe Mining Beijing 100083 China Key Laboratory for the Exploitation of Southwest Resources and Environmental Disaster Control Engineering Ministry of Education Chongqing University Chongqing 400044 China

In order to investigate the change law of different gas permeability of tectonic coal under circumstances of different gas pressure and different stress condition, take the tectonic coal with low permeability and outburst hazard as research object and study on the different gas permeability change law of tectonic coal in complete stress-strain process by using the triaxial servo-controlled seepage equipment for thermo-fluid-solid coupling of coal containing gas. The experimental results show that the complete stress-strain curve of coal containing methane is similar to that of coal containing carbon dioxide, which can be divided into five stages with unique characteristics respectively, and there are the minimum value of permeability corresponding to the neighboring juncture between stage II and phase III in complete stress-strain process. In addition, there are existing Klinkenberg effects not only for absorbing gas, such as methane and carbon dioxide but also for non-absorbing gas such as helium gas in the gas-bearing coal seam. Moreover, the Klinkenberg effect on the methane permeability of coal exists in all the stress condition of coal in complete stress-strain process and that on carbon dioxide permeability of coal only appears in the coal compaction named by phase I. Therefore, occurrence of Klinkenberg effect have something to do with structure of coal mass, but also are related to gas type and stress condition of coal mass.

关键词： Permeability Tectonic Coal methane Carbon dioxide Klinkenberg effect

来源：评论

学校读者我要写书评

暂无评论

Contribution of safety to economic growth: A case study of China mining industry

Contribution of safety to economic growth: A case study of C...

引用

Chinese control and Decision Conference

作者： Haixia, Tan Hongtu, Wang Zaiqing, Wang Lin, Chen Huanlin, Ren Key Lab for Exploitation of China Southwestern Rsrc. and Environmental Disaster Control Engineering Ministry of Education Chongqing University Chongqing 400030 China Institute of Chongqing Geology and Mineral Resources Chongqing 400030 China Exploration Institute of Geology and Mineral Resources Yunnan Bureau of Geology and Mineral Resources Kunming 650051 China College of History and Sociology Huaibei Normal University Huaibei 235000 China

ISBN: (纸本)9781424487363

Safety input is a way of safeguarding mining, as well as one of main reasons for the increased growth rates of Total Factor Productivity (TFP). To figure out the contribution of the safety input to mining economic growth, a new production safety index system with six principal items describing China mining safety was constructed. The study found that China mining production safety level was improved continuously, a more than 17-fold increase from 1991 to 2008. Using co-integration theory and dynamic construction model, a mining economic growth model was established based on the new production safety index system. The empirical results prove that labor input and capital input are still major factors of promoting mining economic growth, and the production safety not only contributed the short-term GDP growth of mining industry but also helped present 8.8% of contribution rate to the long-term elasticity coefficient. © 2011 IEEE.

关键词： Accident prevention

来源：评论

学校读者我要写书评

暂无评论

Analysis of transient temperature field in coke drums

引用

Applied Mathematics and Mechanics(English Edition) 2010年第3期31卷 291-304页

作者：宁志华刘人怀 Key Laboratory of Disaster Forecast and Control in Engineering Ministry of Education of ChinaJinan University Institute of Applied Mechanics and Department of Mechanics and Civil Engineering Jinan University

One of the primary reasons leading to bulging and cracking in a coke drum is the severe temperature gradient due to cyclic temperature variation. Based on the twodimensional heat conduction theory, an analytical solution of the transient temperature field in the coke drum is obtained, which is different from the known FEM results. The length of the coke drum is considered finite. The dynamic boundary conditions caused by fluid uninterrupted rising in oiling and watering stages are simulated with the iteration method. Numerical results show that the present theoretical model can accurately describe basic features of the transient temperature field in the coke drum. Effects of the geometry of the coke drum and the rising velocity of quench water on the axial temperature gradient are also discussed.

关键词： coke drum cylindrical shell transient temperature field temperature gradient

来源：评论

学校读者我要写书评

暂无评论

引用

2011 2nd International Conference on Mechanic Automation and control engineering, MACE 2011

作者： Li, Xiaoshuang Li, Yaoji Yin, Guangzhi He, Lin National Engineering Research Center of Phosphate Resources Development and Utilization Chongqing University Chongqing 400030 China State and Local Joint Engineering Laboratory of Methane Drainage in Complex Coal Gas Seam Chongqing University Chongqing 400030 China Key Lab. for the Rsrc. Exploitation and the Environ. Disaster Control Engineering in Southwest China State Ministry of Education Chongqing University Chongqing 400030 China Yunnan Phosphate Chemical Group Co. LTD. Jinning 650600 China

ISBN: (纸本)9781424494392

Based on the gently inclined medium thick phosphate rock of the deep part of the east mining section of +2150 level of Jinning-Six mine of Yunnan phosphate Co., Ltd, the similar material physical model simulation experiment of the stability of stope pillars under room and pillar mining was carried out by the mine pressure plane stress modeling experimental frame of college of resource and environmental sciences. Based on the experimental results,the deformation and failure changing law of the above roof, surrounding rock mass and stope pillar during the mining along the strike direction of phosphate were investigated. The experimental results showed: (1) With the increasing of the scope of mined-out area, the fwassure zone and separation layer zone of the roof in the original mined-out area of the stope were pressed compact step by step. And when the space range of the mined-out area reached some scale, the deformation of the fwassure zone and separation layer zone of the roof in the original mined-out drived to stabilwasation, and the sustain action of it to the gravity fore of the overlying strata was reexternalization. (2)After the mining, the subsidence region of the overlying strata of the stope mainly concentrated the roof and surrounding rock mass which beside the mined-out area, the position of the maximum subsidence point was in the center zone of the excavation space, with the increasing of the dwastance from the center of the stope along the trend and normal of the ore body, the subsidence value of the overlying strata of the stope was monotone decreasing. With the increasing of the region of the excavation space, the mining influence region and the mining inflence degree of the overlaying strata of the stope gradually increased. And the corresponding position of the maximum subsidence zone dynamically forward leaded, the final subsidence curve of the overlying strata was a bowl shaped curve. (3)The defoemation and failure characterwastics of the overlyin

关键词： Room and pillar mining

来源：评论

学校读者我要写书评

暂无评论

引用

2011 2nd International Conference on Mechanic Automation and control engineering, MACE 2011

ISBN: (纸本)9781424494392

Based on the gently inclined medium thick phosphate rock of the deep part of the east mining section of +2150 level of Jinning-Six mine of Yunnan phosphate Co., Ltd, the similar simulation model experiment of the stability of stope roof under cemented backfilling mining of waste rock was carried out by the mine pressure plane stress modeling experimental frame of college of resource and environmental sciences. Based on the experimental results, the stress changing law of the above roof of stope roof after the filling of stope along the strike direction of phosphate were investigated. Then the gently inclined medium thick phosphate rock of the deep part of the east mining section of Jinning-Six mine of Yunnan phosphate Co., Ltd could efficiently recover, and the surface in mining areas could also be protected. © 2011 IEEE.

关键词： Roofs

来源：评论

学校读者我要写书评

暂无评论

Experimental studies on crack parameters identification in the pipe based on L(0, 2) ultrasonic guided wave

引用

Beijing Ligong Daxue Xuebao/Transaction of Beijing Institute of Technology 2011年第SUPPL.1期31卷 8-11页

作者： Zhang, Wei-Wei Zhao, Jun Nie, Zhen-Hua Sun, Jin-Lan Ma, Hong-Wei Mechanics Department Taiyuan University of Science and Technology Taiyuan Shanxi 030024 China The Key Laboratory of Disaster Forecast and Control in Engineering Jinan University Ministry of Education of China Guangzhou Guangdong 510632 China

PZT5-sensors were used to excite and receive the guided wave signal for crack detection. A piezoelectric ring was an excited sensor and 16 piezoelectric patches distributing the circle pipe wall were received sensors. At first, the disperse curve of both the group velocity and the attenuation for L(0, 2) guided wave were plotted. Next, crack detection was performed by the guided wave inspection. For reducing the noise from the guided wave signal, eight points FFT smoothing technology is used to denoise the guided wave signal. Based on the denoised signal, the crack location can be detected successfully. To evaluate the size of the crack, the reflection coefficient, a ratio of the peak of the echo from the crack to the peak of the incident wave, is defined. When the modify factor is 0.8, it could be found that the crack size identification is in good agreement with the theoretical prediction.

关键词： Damage detection

来源：评论

学校读者我要写书评

暂无评论

Analysis in Law Factor on China Coal Mine Safety Production Based on Dummy Variable Model

Analysis in Law Factor on China Coal Mine Safety Production ...

引用

2011全国特殊气藏开发技术研讨会

作者： TAN Haixia WANG Hongtu REN Huanlin CHEN Lin FAN Xiaogang YUAN Zhigang Academy of Urban and Environment Science Huazhong Normal University Wuhan 430079 China Geology and Mineral Resources Exploration Academy of Yunnan Geology and Mineral Resources Bureau Kunming 650051 China Key Lab for Exploitation of China Southwestern Resources & Environmental Disaster Control Engineering Ministry of Education Chongqing University Chongqing 400030 China

To make clear the factors influence China coal mine safety production, the multiple regression model of the death rate per million tons coal show that level of mechanical coal mining and investment in capital construction per ton coal have a positive effect on coal mine safely production, and per capita GDP a negative *** comparative analyze the direction and magnitude of some significant laws or regulations on coal mine safety production since 1990, a multiple dummy variable model was *** study finds that the implementation of three laws and one regulation average make China death rate per million tons coal more reduced 0.9956 person;and the effects of PRC Coal Law is unworthy on coal mine safely production relative to PRC Mine Safety Law, PRC Safety Production Law and the Regulation of Reporting and Investigating Production Accident, the ratio of deterrent effect of the latter three laws on coal mine safety production is about 6:13:13.

关键词： coal mine safety production law dummy variable model comparative analysis

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：