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Study of the relationship between fractures and highly productive shale gas zones, Longmaxi Formation, Jiaoshiba area in eastern Sichuan

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Petroleum Science 2018年第3期15卷 498-509页

作者： Yu-Feng Li Wei Sun Xi-Wu Liu dian-Wei zhang Yan-Chun Wang Zhi-Yuan Liu School of Geophysics and Information Technology China University of Geoscience Research Institute of Petroleum Exploration and Development Sinopec

Shale fractures are an important factor controlling shale gas enrichment and high-productivity zones in the Longmaxi Formation, Jiaoshiba area in eastern Sichuan. Drilling results have, however, shown that the shale fracture density does not have a straightforward correlation with shale gas productivity. Based on logging data, drilling and seismic data, the relationship between shale fracture and shale gas accumulation is investigated by integrating the results of experiments and geophysical methods. The following conclusions have been drawn：（1） Tracer diffusion tests indicate that zones of fracture act as favorable channels for shale gas migration and high-angle fractures promote gas accumulation.（2） Based on the result of azimuthal anisotropy prediction, a fracture system with anisotropy strength values between 1 and 1.15 represents a moderate development of high-angle fractures, which is considered to be favorable for shale gas accumulation and high productivity, while fracture systems with anisotropy strength values larger than 1.15 indicate over-development of shale fracture, which may result in the destruction of the shale reservoir preservation conditions.

关键词： Azimuthal anisotropy Fracture prediction Shale Shale gas Shale reservoir preservation conditions

Application of distributed model predictive control based on neighborhood optimization in gauge-looper integrated system of tandem hot rolling

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Journal of Iron and Steel Research International 2023年第2期30卷 277-292页

作者： Jie Sun Fan Hou Yun-jian Hu Long-jun Wang Hao-yue Jin Wen Peng Xiao-jian Li dian-hua zhang State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819LiaoningChina

To solve the coupling relationship between the strip automatic gauge control and the looper control in traditional control strategy of tandem hot rolling,a distributed model predictive control(DMPC)strategy for the tandem hot rolling was explored,and a series of simulation experiments were carried ***,based on the state space analysis method,the multivariable dynamic transition process of hot strip rolling was studied,and the state space model of a gauge-looper integrated system in tandem hot rolling was ***,DMPC strategy based on neighborhood optimization was proposed,which fully considered the coupling relationship in this integrated ***,a series of experiments simulating disturbances and emergency situations were completed with actual rolling *** experimental results showed that the proposed DMPC control strategy had better performance compared with the traditional proportional-integral control and centralized model predictive control,which is applicable for the gauge-looper integrated system.

关键词： Tandem hot rolling Gauge Looper integrated system State space model Distributed model predictive control Neighborhood optimization

Calculation Method of Optimal Speed Profile for Hot Plate During Controlled Cooling Process

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Journal of Iron and Steel Research International 2011年第5期18卷 38-41页

作者： WANG Bing-xing CHEN Xiao-lin TIAN Yong WANG Zhao-dong WANG Jun zhang dian-hua State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110004LiaoningChina

The healthy and rapid development of the controlled cooling technology was hampered by the uneven cooling phenomenon. During the process of hot plate production,the homogeneous cooling along the length direction of plate was constrained by lots of factors. And because the speed was a flexible control parameter,the calculation method of optimal speed profile was developed based on the measured start cooling temperature and its matrix equation was solved by the Cholesky decomposition method. The optimal speed profile was used in online control system. As a result,the temperature distribution along the plate length direction was relatively uniform,and 95% of measured final cooling temperature difference from the target temperature 700 ℃ was controlled within ±20 ℃.

关键词： plate controlled cooling homogeneous cooling speed profile Cholesky decomposition method

Use of QSAR and SSD methods on deriving predicted no-effect concentrations in seawater and sediment for ten individual parent-and alkyl-PAHs and a case study on the assessment of their ecological risks from the Dalian Bay, China

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Acta Oceanologica Sinica 2020年第12期39卷 95-105页

作者： Ying Wang Xing Liu Yi Cong Jin Fei Juying Wang dian zhang Liang Liu Jingli Mu Ziwei Yao Key Laboratory for Ecological Environment in Coastal Areas of Ministry of Ecology and Environment National Marine Environmental Monitoring CenterDalian 116023China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Third Institute of Oceanography Ministry of Natural ResourcesXiamen 361005China

Parent and alkylated polycyclic aromatic hydrocarbons(alkyl-PAHs),which are a class of important toxic components of crude oil especially in the marine environment,exhibit adverse effects on aquatic life and potentially pose a human health ***,the lack of chronic toxicity data is one of the hindrances for alkylPAHs when assessing their ecological *** this study,predicted no-effect concentrations(PNECs)in seawater and marine sediment for ten parent-and alkyl-PAHs were derived by applying species sensitivity distributions(SSDs)and quantitative structure-activity relationships(QSARs).The local area,Dalian Bay,where an oil-spilled accident happened in 2010,was chosen as a case site to assess ecological risks for ten PAHs in surface seawaters and marine *** PNECs in seawater and sediment for protecting aquatic organisms in marine ecosystems were calculated and recommended in the range of 0.012-2.79μg/L and 48.2-1337 ng/g(dry weight),***,the derived PNECs for the studied PAHs in seawater and marine sediment were comparable to those obtained by classical *** quotient results indicate low ecological risks to ecosystems for ten parent-and alkyl-PAHs in surface seawaters and surface sediments from the Dalian *** findings provide a first insight into the PNECs and ecological risks of alkyl-PAHs,emphasizing the role of the computational toxicology in ecological risk *** use of QSARs has been identified as a valuable tool for preliminarily assessing ecological risks of emerging pollutants,being more predictable of real exposure scenarios for risk assessment purposes.

关键词： alkyl-PAHs QSARs PNECs ecological risks Dalian Bay

Application of Parallel Mechanism in Varistructured Quadruped/Biped Human-carrying Walking Chair Robot

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International Journal of Automation and computing 2013年第5期10卷 447-454页

作者： Ling-Feng Sang Hong-Bo Wang dian-Fan zhang Zhen-Hua Tian Fu-Hai Deng De-Lei Fang Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan University Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of Education Yanshan University Science and Technology Research Institute Yanshan University

For the existing problems of walking chair robot such as simple function,lower bearing capacity and not walking in complex environment,a novel varistructured quadruped / biped human-carrying walking chair robot is *** proposed robot could be used as biped and quadruped walking chair *** the conversion of the walking chair robot from the quadruped to the biped or vice versa,6-UPS and 2-UPS＋UP（U,P and S are universal joint,the prismatic pair,and sphere joint,respectively） parallel mechanisms are selected as the leg mechanism of the biped walking robot and quadruped walking robot,*** the screw theory and theory of mechanism,the degrees of freedom of the leg mechanism and the body mechanism in diferent motion states are computed so as to meet the requirements of mechanism *** motion characteristics of the 2-UPS＋UP parallel mechanism which is the key part of the walking chair robot are ***,the workspace of the moving platform is drawn and the efect of the structural parameters on the workspace volume is ***,it is found that the volume of the workspace of the moving platform is bigger when the side length ratio and the vertex angle ratio of the fxed platform and the moving platform which are isosceles triangles are close to *** study provides a theoretical foundation for the prototype development.

关键词： Human-carrying walking chair robot parallel leg mechanism degree of freedom varistructure workspace kinematics

Some Discussions on the Improvements in the English-Chinese Dictionary （unabridged）

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Sino-US English Teaching 2004年第2期1卷 70-77页

作者： dian ＇en zhang Tangshan Teacher＇s College

Based on the comparison between the improvements in the English-Chinese Dictionary and A New English-Chinese Dictionary some discussions are made on the improvements in the English＇Chinese Dictionary in terms of macrostructure and microstructure. Therefore, some differences are highlighted, with which users can make better use of the English-Chinese Dictionaries.

关键词： differences macrostructure microstructure

An Inquiry to College English Written Communication

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校园英语 2015年第33期 9-10页

作者： zhang dian Department of Foreign Languages Hunan University of Humanities Science and Technology

This paper discusses the strategies for college English writing teaching and learning from the perspective of the communicativeness of writing on the analysis of the situation of college English writing teaching and l... 详细信息

关键词： inquiry College English Written communication

Algorithm Design and Application of Laminar Cooling Feedback Control in Hot Strip Mill

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Journal of Iron and Steel Research International 2012年第4期19卷 39-42页

作者： LIU En-yang zhang dian-hua SUN Jie PENG Liang-gui GAO Bai-hong SU Li-tao State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110819 LiaoningChina Shenyang Machine Tool Co Ltd Shenyang 110004 Liaoning China Sales Company ofShougang Group Beijing 100043 China

Feedback control is one of the most important ways to improve coiling temperature control precision during laminar cooling *** cooling equipments of a hot strip mill and structure of the control system were *** control algorithm based on PI controller and that based on Smith predictor were designed and tested in a hot strip mill *** application shows that the feedback control system based on PI controller plays a limited role in improving coiling temperature control *** feedback control system based on Smith predictor runs stable and *** the measured coiling temperature deviates from the target value,it can be adjusted to the required range quickly and steadily by Smith predictor feedback control,which improves the coiling temperature control precision greatly,and qualities of hot rolled strips are improved significantly

关键词： hot strip mill laminar cooling feedback control Smith predictor PI controller

An analysis of the motivational effect on employees of Maslow＇s Hierarchy of Needs in international culture circumstances

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International Journal of Technology Management 2017年第3期 77-78页

作者： zhang dian Jiangxi University of Finance and Economics 330013Nanchang China Jiangxi College of Foreign Studies 330099Nanchang China

Maslow＇ s Hierarchy of Needs, which is one of the important motivation theories, has become a strategy used by managers to motivate employees. The project will explain the definition of motivation and Maslow＇ s Hierarchy of Needs from the perspective of organizational behavior and the strengths and weaknesses of the theory. Then it will consider how the theory is applied effectively in the USA and Northwest Europe and ineffectively in some developing and undeveloped countries with different economical backgrounds, political systems and cultural preferences. The conclusion suggests that managers should choose motivation systems that fit in the local cultural backgrounds.

关键词： motivational effect Maslow' s Hierarchy of Needs culture