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A MESSAGE-DRIVING FORMALISM FOR MODELING AND SIMULATION OF MULTI-AGENT SUPPLY CHAIN SYSTEMS

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Journal of Systems Science and Systems Engineering 2011年第4期20卷 385-399页

作者： Wenzhe TAN1 Yueting CHAI2 Yi LIU3 1department of Automation, Tsinghua university, beijing, 100084, china 2department of Automation, Tsinghua university, beijing, 100084, china 3department of Automation, Tsinghua university, beijing, 100084, china department of Automation Tsinghua University Beijing China

To acquire a competitive advantage in the expanding market, manufacturing enterprises should be able to manage their supply chains as effectively as possible. It is now becoming popular to model supply chains as multi-agent systems and use discrete event simulation to learn more about their behaviors or investigate the implications of alternative configurations. In order to enhance the computational efficiency and keep the simulation credibility, this paper proposes a message-driving formalism for the simulation of multi-agent supply chain systems. Through the message-driving formalism, the problem of shared variables is addressed and the parallel operation of agents is implemented. Simulation experiments with a prototype implementation show that the message-driving formalism is able to provide credible results in significantly less simulation time.

关键词： Supply chain multi-agent system modeling and simulation parallel discrete event simulation message-driving formalism

CONVERGENCE OF THE POINT VORTEX METHODS FOR EULER EQUATION ON HALF PLANE

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Journal of Computational Mathematics 1996年第3期14卷 213-222页

作者： P.W. Zhang(department of Mathematics, beijing university, beijing, china) 北京大学数学系北京

In this paper, we study the point vortex method for 2-D Euler equation of incompressible how on the half plane, and the explicit Euler's scheme is considered with the reflection method handling the boundary condition.... 详细信息

关键词： Math CONVERGENCE OF THE POINT VORTEX METHODS FOR EULER EQUATION ON HALF PLANE Zhang

Micro-mechanisms of residual oil mobilization by viscoelastic fluids

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petroleum Science 2008年第1期5卷 56-61页

作者： Zhang Lijuan Yue Xiang＇an Guo Fenqiao Key Laboratory of petroleum Engineering Ministry of Education China University of Petroleum Beijing 102249 China Development department Sinopec Exploration and Production Research Institute Beijing 100083 China

Four typical types of residual oil, residual oil trapped in dead ends, oil ganglia in pore throats, oil at pore corners and oil film adhered to pore walls, were studied. According to main pore structure characteristics and the fundamental morphological features of residual oil, four displacement models for residual oil were proposed, in which pore-scale flow behavior of viscoelastic fluid was analyzed by a numerical method and micro-mechanisms for mobilization of residual oil were discussed. Calculated results indicate that the viscoelastic effect enhances micro displacement efficiency and increases swept volume. For residual oil trapped in dead ends, the flow field of viscoelastic fluid is developed in dead ends more deeply, resulting in more contact with oil by the displacing fluid, and consequently increasing swept volume. In addition, intense viscoelastic vortex has great stress, under which residual oil becomes small oil ganglia, and finally be carried into main channels. For residual oil at pore throats, its displacement mechanisms are similar to the oil trapped in dead ends. Vortices are developed in the depths of the throats and oil ganglia become smaller. Besides, viscoelastic fluid causes higher pressure drop on oil ganglia, as a driving force, which can overcome capillary force, consequently, flow direction can be changed and the displacing fluid enter smaller throats. For oil at pore corners, viscoelastic fluid can enhance displacement efficiency as a result of greater velocity and stress near the corners. For residual oil adhered to pore wall, viscoelastic fluid can provide a greater displacing force on the interface between viscoelastic fluid and oil, thus, making it easier to exceed the minimum interfacial tension for mobilizing the oil film.

关键词： Viscoelastic chemical flooding displacement mechanism residual oil swept volume

A study of different fluid droplets impacting on a liquid film

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petroleum Science 2008年第1期5卷 62-66页

作者： Huang Qiyu Zhang Holden petroleum Engineering department The University of Tulsa Tulsa OK 74104 USA beijing Key Laboratory of Urban Oil and Gas Distribution Technology China University of Petroleum Beijing 102249China

Knowledge of droplet dynamics provides the basis of predicting pressure drops, holdups and corrosion inhibitor distribution in multiphase flow. Droplet size and its distribution also determine the separation efficiency between different phases. Experimental observations were conducted for droplet impingements with different fluids, droplet sizes and velocities, and film thicknesses. The observed transition boundaries were compared with the models developed by different authors. For impingement on a deep pool surface, the Marengo and Tropea correlation for splashing does not agree with the experimental results in this study. The Bai and Gosman critical Weber number for bouncing agrees with the water results but not the oil results. Three new correlations for transition boundaries between bouncing, coalescence, jetting and splashing were proposed and compared with the experimental observations.

关键词： Droplet liquid film transition boundary high-speed video

Diagenesis and Restructuring Mechanism of Oil and Gas Reservoir in the Marine Carbonate Formation,Northeastern Sichuan:A Case Study of the Puguang Gas Reservoir

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Acta Geologica Sinica(English Edition) 2009年第6期83卷 1173-1181页

作者： DU Chunguo1, 2, WANG Jianjun1, ZOU Huayao2, ZHU Yangming3 and WANG Cunwu4 1 Research Institute of petroleum Exploration and Development, beijing 100034, china 2 petroleum university of china, beijing 102249, china 3 department of Earth Science, Zhejiang university, Hangzhou 310027, china 4 Faculty of Earth Resources, china university of geosciences, Wuhan 430074, china Research Institute of petroleum Exploration and Development Beijing 100034 China petroleum university of china Beijing 102249 China department of Earth Science Zhejiang University Hangzhou 310027 China Faculty of Earth Resources China University of Geosciences Wuhan 430074 China

Based on the technology of balanced cross-section and physical simulation experiments associated with natural gas geochemical characteristic analyses, core and thin section observations, it has been proven that the Puguang gas reservoir has experienced two periods of diagenesis and restructuring since the Late Indo-Chinese epoch. One is the fluid transfer controlled by the tectonic movement and the other is geochemical reconstruction controlled by thermochemical sulfate reduction (TSR). The middle Yanshan epoch was the main period that the Puguang gas reservoir experienced the geochemical reaction of TSR. TSR can recreate the fluid in the gas reservoir, which makes the gas drying index higher and carbon isotope heavier because C2+ (ethane and heavy hydrocarbon) and 12C (carbon 12 isotope) is first consumed relative to CH4 and 13C (carbon 13 isotope). However, the reciprocity between fluid regarding TSR (hydrocarbon, sulfureted hydrogen (H2S) , and water) and reservoir rock results in reservoir rock erosion and anhydrite alteration, which increases porosity in reservoir, thereby improving the petrophysical properties. Superimposed by later tectonic movement, the fluid in Puguang reservoir has twice experienced adjustment, one in the late Yanshan epoch to the early Himalayan epoch and the other time in late Himalayan epoch, after which Puguang gas reservoir is finally developed.

关键词： diagenesis and restructuring mechanism marine carbonate formation thermochemical sulfate reduction Puguang gas reservoir

Geochemical characteristics and origin of gases from the Upper,Lower Paleozoic and the Mesozoic reservoirs in the Ordos Basin,china

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Science china Earth Sciences 2008年第S1期51卷 183-194页

作者： HU AnPing 1 ,Li Jian 2 ,ZHANG WenZheng 3 ,LI ZhiSheng 2 ,HOU Lu 4 &LIU QuanYou 5 1 department of Earth Sciences,Zhejiang university,Hangzhou 310027,china 2 Langfang Branch,Reasearch Institute of petroleum Exploration and Development,Petrochina,Langfang 065007,china 3 Institute of Exploration and Development,Petrochina Changqing Oilfield Company,Xi’an 710021,china 4 university of petroleum,beijing102249,china 5 Petrochina Research Institute of petroleum Exploration and Development,beijing 100083,china department of Earth Sciences Zhejiang University Hangzhou China Langfang Branch Reasearch Institute of Petroleum Exploration and Development PetroChina Langfang China Institute of Exploration and Development PetroChina Changqing Oilfield Company Xi’an China university of petroleum Beijing China Petrochina Research Institute of petroleum Exploration and Development Beijing China

The Ordos Basin,the second largest sedimentary basin in china,contains the broad distribution of natural gas *** far,several giant gas fields have been discovered in the Upper and Lower Paleozoic in this basin,each having over 1000×10 8 m 3 of proven gas reserves,and several gas pools have also been discovered in the *** paper collected the data of natural gases and elucidated the geochemical characteristics of gases from different reservoirs,and then discussed their *** hydrocarbons preserved in the Upper Paleozoic,the elevatedδ13C values of methane,ethane and propane indicate that the gases would be mainly coal-formed gases;the singular reversal in the stable carbon isotopes of gaseous alkanes suggests the mixed gases from humic sources with different *** the Lower Paleozoic,theδ13C 1 values are mostly similar with those in the Upper Paleozoic,but theδ13C 2 andδ13C 3 values are slightly lighter,suggesting that the gases would be mixing of coal-type gases as a main member and oil-type *** are multiple reversals in carbon isotopes for gaseous alkanes,especially abnormal reversal for methane and ethane(i.e.δ13C 1 >δ13C 2 ),inferring that gases would be mixed between high-mature coal-formed gases and oil-type *** the Mesozoic,the δ13Cvalues for gaseous alkanes are enriched in 12C,indicating that the gases are mainly derived from sapropelic sources;the carbon isotopic reversal for propane and butane in the Mesozoic is caused by microbial oxidation and mixing of gases from sapropelic sources with different *** contrast to the Upper Paleozoic gases,the Mesozoic gases are characterized by heavier carbon isotopes of iso-butane than normal butane,which may be caused by gases generated from different kerogen types. Finally,according toδ13C 1 -Ro relationship and extremely low total organic carbon contents,the Low Paleozoic gases would not be generated from the Ordovician source as a main gas source,bycontrast, the Upper Pale

关键词： Ordos Basin natural gas chemical composition carbon isotope genesis

STATISTICAL EVALUATION OF CRITICAL INCLUSION FACTOR FOR SECONDARY RECRYSTALLIZATON IN 3%Si STEEL Lecturer,department of Materials Engineering,Southwestern Jiaotong university,Chengdu 610031,china

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Acta Metallurgica Sinica(English Letters) 1990年第5期3卷 327-331页

作者： LI Shuchen Southwestern Jiaotong university,Chengdu,chinaCHEN Mengzhe KE Jun university of Science and Technology beijing,beijing,china

On the basis of statistical data of MnS in the conventional 3% Si steel sheeets after various annealing processes,the critical inclusion factor has been evaluated to be 20 mm^(-1).The inhi- bition of MnS to grain grow... 详细信息

关键词： 3%Si steel secondary recrystallization inclusion factor

Synthesis of ZnS from organic sulfur in petroleum coke and its photocatalysis properties

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petroleum Science 2010年第2期7卷 268-272页

作者： Zheng Yanjun Wang Xudong Cui Lishan State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China department of Materials Science and Engineering China University of Petroleum Beijing 102249 China Technical department Construction Division Offshore Oil Engineering Co. Ltd Mailbox 595 Tianjin 300452 China

Organic sulfur in high sulfur petroleum coke was treated as the S source for synthesis of ZnS photocatalyst. Experimental results showed that with ball milling and subsequent heating treatment, ZnS compound could be successfully synthesized and showed considerable photocatalysis activity for decomposing industrial pollutants. The concentration of methyl orange or ethylene blue may be lowered to less than 5% after being decomposed by the synthesized-ZnS photocatalysis. Results of this study suggested a potential technique of turning high sulfur petroleum cokes from industrial wastes into useful products for environment improvement.

关键词： petroleum coke photocatalysis ZnS ball milling high-sulfur

Effective-Medium Theory for Two-Phase Random Composites with and Interfacial Shell

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Journal of Materials Science & Technology 2000年第4期16卷 367-369页

作者： Qingzhong XUE (department of Physics, university of petroleum, Dongying 257062, china) department of Physics University of Petroleum Dongying 257062 China

According to the Bruggeman theory and Maxwell-Garnett theory, the effective dielectric constant of a two-phase random composite with an interfacial shell is presented. The nonlinearity of the theory is obvious. Especially, the theory is suited to study the dielectric properties of two-phase random composites with a spherical interfacial shell. The theoretical results on dielectric properties of polystyrene-barium titanate composites with an interfacial shell are in good agreement with experimental data.

关键词： Zhang Effective-Medium Theory for Two-Phase Random Composites with and Interfacial Shell Wang