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Journal of Thermal Science 2019年第3期28卷 585-595页

作者： ZHAI Xiaowei XU Yu YU Zhijin College of Safety Science and Engineering Xi'an University of Science and Technology Shaanxi Key Laboratory of Prevention and Control of Coal Fire

LCO_2(liquid CO_2) can absorb heat and release latent heat via phase transition, which can provide considerable cooling energy and effectively solve the problem of thermal damage in deep coal mining processes. A LCO_2 cycle refrigeration system is designed to continuously cool down the working face in a mine, and CO_2 is cyclically utilized. Additionally, LCO_2 is used not only as a cold source but also to prevent spontaneous combustion of coal in the gob. COMSOL Multiphysics simulation software is used to characterize the thermal performance of the heat exchange system, where the heat transfers between the CO_2 and the airflow. For a LCO_2 consumption of 13.54 m^3/h, the temperature of the airflow in the tunnel decreases by 7.72°C, and the cooling volume of the system reaches 142.99 kW/h; the cooling volume provides a latent heat release of 46.68 k W/h. The main influencing factors of the refrigeration system, such as ventilation flux, LCO_2 flow, LCO_2 temperature and initial tunnel temperature, are also analyzed quantitatively through the software. The temperature of the steady airflow in the tunnel is proportional to the square of the local fan ventilation flux, and it decreases linearly with an increase in the LCO_2 flow but increases with both the temperature of the LCO_2 and the initial temperature in the tunnel. When the temperature difference between the LCO_2 and wind increases, the heat exchange between the CO_2 and wind intensifies, and the cooling volume increases.

关键词： LCO2 refrigeration working face cooling numerical simulation heat exchange

DISTRIBUTION LAW OF RANDOM UNBALANCE RESPONSE OF MULTISTAGE BLOWER

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中国有色金属学会会刊：英文版 1998年第1期8卷 165-168页

作者： Tan, Qing Zhong, Jue Central South Univ of Technology Changsha China

ＤＩＳＴＲＩＢＵＴＩＯＮＬＡＷＯＦＲＡＮＤＯＭＵＮＢＡＬＡＮＣＥＲＥＳＰＯＮＳＥＯＦＭＵＬＴＩＳＴＡＧＥＢＬＯＷＥＲ①ＴａｎＱｉｎｇａｎｄＺｈｏｎｇＪｕｅＣｏｌｅｇｅｏｆＭｅｃｈａｎｉｃａｌａｎｄＥｌｅｃｔｒｉｃａｌ... 详细信息

ＤＩＳＴＲＩＢＵＴＩＯＮＬＡＷＯＦＲＡＮＤＯＭＵＮＢＡＬＡＮＣＥＲＥＳＰＯＮＳＥＯＦＭＵＬＴＩＳＴＡＧＥＢＬＯＷＥＲ①ＴａｎＱｉｎｇａｎｄＺｈｏｎｇＪｕｅＣｏｌｅｇｅｏｆＭｅｃｈａｎｉｃａｌａｎｄＥｌｅｃｔｒｉｃａｌＥｎｇｉｎｅｒｉｎｇ，Ｃｅｎｔｒａ...

关键词： unbalance distribution random experiment method vibration response centrifugal blower overcritical rotating speed autobalance technology working condition diagnosis

Evaluation of the Fatigue Characteristics of Laser-processed Hot Work Tool Steel Based on Reliability

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Journal of Materials Science & Technology 2003年第Z1期19卷 83-85页

作者： Satoshi HANAKI Yahong SUI Masato YAMASHITA Hitoshi UCHIDA Hironobu TSUJII Graduate School of Engineering Himeji Institute of Technology Japan Himeji Institute of Technology Japan Graduate School of Engineering Himeji Institute of Technology Japan Graduate School of Engineering Himeji Institute of Technology Japan Technical Research Laboratories Sanyo Special Steel Co Japan

It is reported that laser-processing is effective to repair the heat checks, which are fine shallow cracks on a surfaceof die-casting dies. In this study, the rotating bending fatigue tests have been carried out to evaluate the fatiguecharacteristics of laser-processed hot working tool steel. Because test results are scattered, S-N curves are decidedbased on the evaluation of fatigue strength distribution. As a result, the fatigue strength of the laser-processedspecimens decreases remarkably in comparison with that of base metal. However, it can be recovered to almostinitial value by heat treatment at secondary hardening temperature. This procedure is also effective to decrease thescatter of fatigue strength. The laser-processing can be carried out at low cost and this method is effective for theextension of the work life of dies.

关键词： Hot working tool steel, Laser-processing, S-N curve, Fatigue strength, Reliability

Soft-sensing modeling and intelligent optimal control strategy for distillation yield rate of atmospheric distillation oil refining process

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Chinese Journal of Chemical Engineering 2019年第5期27卷 1113-1124页

作者： Zheng Wang Cheng Shao Li Zhu Institute of Advanced Control Technology Dalian University of Technology

It is a challenge to conserve energy for the large-scale petrochemical enterprises due to complex production process and energy diversification. As critical energy consumption equipment of atmospheric distillation oil refining process, the atmospheric distillation column is paid more attention to save energy. In this paper, the optimal problem of energy utilization efficiency of the atmospheric distillation column is solved by defining a new energy efficiency indicator - the distillation yield rate of unit energy consumption from the perspective of material flow and energy flow, and a soft-sensing model for this new energy efficiency indicator with respect to the multiple working conditions and intelligent optimizing control strategy are suggested for both increasing distillation yield and decreasing energy consumption in oil refining process. It is found that the energy utilization efficiency level of the atmospheric distillation column depends closely on the typical working conditions of the oil refining process, which result by changing the outlet temperature, the overhead temperature, and the bottom liquid level of the atmospheric pressure tower. The fuzzy C-means algorithm is used to classify the typical operation conditions of atmospheric distillation in oil refining process. Furthermore, the LSSVM method optimized with the improved particle swarm optimization is used to model the distillation rate of unit energy consumption. Then online optimization of oil refining process is realized by optimizing the outlet temperature, the overhead temperature with IPSO again. Simulation comparative analyses are made by empirical data to verify the effectiveness of the proposed solution.

关键词： Energy efficiency optimization Crude oil distillation Particle warm optimization Fuzzy C-means algorithm working condition

The law as it relates to subsidence as a consequence of mining activity in Britain

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中国有色金属学会会刊：英文版 2005年第S1期15卷 258-261页

作者： G. T. Powell K. Leighfield University of Glamorgan Wales United KingdomUniversity of Glamorgan Wales United Kingdom

Subsidence as a consequence of mining activity has been an onerous problem associated with mineral extraction in Britain. Mining law as it relates to subsidence has developed over several centuries. This paper will outline the legal implications for mineral subsidence and compensation, considering both common law and statute. Particular reference is made to the extraction of coal, salt in brine, protection of public utilities, working facilities orders, ironstone and ancient mining rights.

关键词： subsidence compensation coal working facilities orders

装载机工作装置模糊自适应PID电液比例系统设计（英文）

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机床与液压 2015年第18期43卷 99-104页

作者：徐秀芬新乡学院机电工程学院河南新乡453000

以ZL40G装载机为研究对象,根据装载机工作装置电液比例控制系统的结构建立其数学模型;采用模糊自整定PID参数法设计了位置控制器,运用Matlab/SIMULINK模块进行了仿真研究;通过与普通PID算法的仿真结果进行比较,结果表明:采用模糊自整定... 详细信息

以ZL40G装载机为研究对象,根据装载机工作装置电液比例控制系统的结构建立其数学模型;采用模糊自整定PID参数法设计了位置控制器,运用Matlab/SIMULINK模块进行了仿真研究;通过与普通PID算法的仿真结果进行比较,结果表明:采用模糊自整定PID参数法能消除系统负载干扰,可显著提高稳态特性,具有较好的自适应能力。

关键词： Loader, working device, Fuzzy control, PID, Position control, Simulation

Energy efficiency evaluation based on DEA integrated factor analysis in ethylene production

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Chinese Journal of Chemical Engineering 2017年第6期25卷 793-799页

作者： Shixin Gong Cheng Shao Li Zhu Institute of Advanced Control Technology Dalian University of Technology Dalian 116024 China

Energy efficiency evaluation plays an important role in energy efficiency improvement of the ethylene production. It is observed from the actual production data that the ethylene production energy efficiency often varies with the complex production working conditions. In the favored methods for energy efficiency evaluation,DEA models may show poor resolution when directly used to evaluate the efficiency values. Therefore, a new energy efficiency evaluation method for ethylene production is proposed based on DEA integrated factor analysis with respect to operation classification. Three key factors, including raw material composition, cracking depth and load rate, are taken into account in determining the production working conditions by means of k-means algorithm. Based on the multi-working conditions mode the energy efficiency evaluation of the ethylene production is made by using DEA model, where the most related energy data are screened by factor ***, the supporting decision of energy efficiency improvement is provided to the operators. The accuracy and effectiveness of the proposed method are illustrated by applying in a practical ethylene production,which gives more effective energy efficiency evaluation in the complicated working conditions of ethylene production with declined dimension of input indicators.

关键词： Energy efficiency evaluation DEA k-means Factor Analysis Production working condition

Experimental Study of Performance of Thermoelectric Refrigerator under Different Intensity of Heat Emission

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湖南大学学报（自然科学版） 2009年第S1期36卷 127-130页

作者： HAN Tian-he,TANG Guang-fa,GONG Guang-cai,LI Tao,LIU Zhong-bing(College of Civil Engineering,Hunan University,Changsha,Hunan 410082,China) College of Civil Engineering Hunan University Changsha 410082 China

Heat emission and the voltage are the main factors affecting the refrigerating capacity of semiconductor *** experiments were designed to obtain their influence on refrigerating capacity of semiconductor and the interaction between heat emission and the *** results show that fixing the heat dissipation,there is an optimal working voltage for the semiconductor module;and if improving the heat emission,the refrigerating capacity increases and the optimal voltage becomes *** can provide the basis for the optimal design of semiconductor refrigeration.

关键词： semiconductor refrigeration heat emission optimal working voltage

Application of PCC pile in soil improvement of highway

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Journal of Central South University 2008年第S2期15卷 108-113页

作者：刘芝平刘汉龙谭慧明 Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai University Geotechnical Research Institute Hohai University Earthquake Research Institute of Jiangsu Province

The construction process and load-bearing behaviors of Cast-in-place concrete thin-wall pipe piles are analyzed based on its application on Yantong Expressway Project. The low strain test, static load test and field excavation were also carried out, and the bearing capacity of the new pile can meet the requirements of design. With the increase of pile diameter, the bearing capacity is increased. The settlement of composite foundation is decreased, when the replacement ratio of pile is increased. The test results also show that the load carried by inner soils is neglectable. According to the tests and application, it can be concluded that the new type of pile is convenient to construction with high bearing capacity and reliable quality, which has great potential in practical engineering.

关键词： PCC pile soil improvement working mechanism bearing capacity

SUMMARY OF CHINA-MADE X-RAY THICKNESS GAUGES FOR STEEL INDUSTRIES

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Nuclear Science and Techniques 1993年第2期4卷 86-90页

作者：乐茂生花宗正 Shanghai Electrical Apparatus Research Institute Shanghai 200063 China

There are two kinds of China- made X- ray thickness gaugemeters i.e. dual beam- dual detector system and single beam- single detector system- SM series, the latter is used dominantly in Chinese steel industries. The performance comparison between domestic and foreign instruments as well as its developments and applications is presented in this paper.

关键词： X- ray thickness gaugemeters Uses Performance Performance testing Steels Industrial plants working conditions