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WEB SERVICES COMPOSING BY MULTIAGENT NEGOTIATION

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Journal of Systems Science & Complexity 2008年第4期21卷 597-608页

作者： jian TANG Liwei ZHENG Zhi jin Institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China. Institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China Institute of Computing Technology Beijing 100190 China.

Composing web services is gained daily attention in Service Oriented Computing. It includes the dynamic discovery, interaction and coordination of agent-based semantic web services. The authors first follow Function Ontology and Automated Mechanism Design for service agents aggregating. Then the problem is formulated but it is ineffective to solve it from the traditional global view. Because the complexity is NP-complete and it is dii^cult or even impossible to get some personal information. This paper provides a multi-agent negotiation idea in which each participant negotiates under the condition of its reservation payoff being satisfied. Numerical experiment is given and well evaluates the negotiation.

关键词： Feasible coalition multi-agent systems negotiation web services composing.

Integrated HI emission in galaxy groups and clusters

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Research in Astronomy and Astrophysics 2017年第10期17卷 15-26页

作者： Mei Ai ming Zhu jian Fu National Astronomical Observatories Chinese Academy of Sciences Key Laboratory of Radio Astronomy Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences

The integrated HI emission from hierarchical structures such as groups and clusters of galax- ies can be detected by FAST at intermediate redshifts. Here we propose to use FAST to study the evolution of the global HI content of clusters and groups over cosmic time by measuring their integrated HI emissions. We use the Virgo Cluster as an example to estimate the detection limit of FAST, and have estimated the integration time to detect a Virgo type cluster at different redshifts （from z = 0.1 to z ---- 1.5）. We have also employed a semi-analytic model （SAM） to simulate the evolution of HI contents in galaxy clusters. Our simulations suggest that the HI mass of a Virgo-like cluster could be 2-3 times higher and the physical size could be more than 50% smaller when redshift increases from z = 0.3 to z = 1. Thus the integration time could be reduced significantly and gas rich clusters at intermediate redshifts can be detected by FAST in less than 2 hours of integration time. For the local Universe, we have also used SAM simulations to create mock catalogs of clusters to predict the outcomes from FAST all sky surveys. Comparing with the optically selected catalogs derived by cross matching the galaxy catalogs from the SDSS survey and the ALFALFA survey, we find that the HI mass distribution of the mock catalog with 20 s of integration time agrees well with that of observations. However, the mock catalog with 120 s of integration time predicts many more groups and clusters that contain a population of low mass HI galaxies not detected by the ALFALFA survey. A future deep HI blind sky survey with FAST would be able to test such prediction and set constraints on the numerical simulation models. The observational strategy and sample selections for future FAST observations of galaxy clusters at high redshifts are also discussed.

关键词： galaxy clusters -- neutral hydrogen (HI) -- galaxy evolution

Thermal Stability of Nanocrystalline AZ31 Magnesium Alloy Fabricated by Surface Mechanical Attrition Treatment

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Acta Metallurgica Sinica(English Letters) 2015年第9期28卷 1162-1169页

作者： jiang-Man Xu Yong Liu Bin jin Jia-Xin Li Shi-ming Zhai Xiang-Jie Yang jian Lu Key Laboratory of Near Net Forming of jiangxi Province Nanchang University Department of Mechanical and Biomedical Engineering City University of Hong Kong Centre for Advanced Structural Materials City University of Hong Kong Shenzhen Research Institute

A nanocrystalline layer （NL） was fabricated on the surface of AZ31 magnesium （Mg） alloy sheet by surface mechanical attrition treatment （SMAT）. The microstructure of the Mg alloy was characterized by optical microscopy, X-ray diffraction and microhardness test. The results showed that both the microstructure and microhardness of AZ31 Mg alloy sheet after SMAT revealed a gradient distribution along depth from surface to center. The thermal stability of the NL was investigated through characterizing the microstructure evolution during the post-isothermal annealing treatment within the temperature range from 150 to 250℃. The NL exhibits a certain degree of thermal stability below 150 ℃, while it disappears quickly when annealing at the temperature range of 200-250 ℃. The grain growth kinetics of the nanocrystalline of AZ31 Mg alloy induced by SMAT was investigated. The activation energy of nanocrystalline AZ31 Mg alloy was obtained with a value of 92.8 kJ/mol.

关键词： Magnesium alloy Thermal stability Surface mechanical attrition treatment Nanocrystalline structure Gradient structure

Rufoolivacin B,a novel polyketide pigment from the fruiting bodies of the fungus Cortinarius rufo-olivaceus(basidiomycetes)

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Chinese Chemical Letters 2009年第11期20卷 1324-1326页

作者： An Ling Zhang jian Chun Qin ming Sheng Bai jin ming Gao Ya Mei Zhang Sheng Xiang Yang Hartmut Laatsch College of Science Northwest A & F University Yangling Shaanxi 712100 China Department of Orgnic Chemistry University of Gottingen Tammannstrasse 2 D-3 7077 Gottingen Germany College of Life Sciences Northwest A & F University Yangling Shaanxi 712100 China Center for Experiments & Education Technology Linyi Normal University Linyi Shandong 276005 China

A novel polyketide pigment （1） with the 4＇,10-coupled linkage between 1-naphthalenol and 1,4-anthraquinone, named rufoolivacin B together with the known analog rufoolivacin （2）, has been isolated from the fruiting bodies of the Chinese toadstool Cortinarius rufo-olivaceus （basidiomycetes）. Their structures were characterized by means of analysis of spectroscopic methods, including 2D-NMR experiments and HR-ESI-MS.

关键词： Anthraquinone Polyketide Basidiomycetes Cortinarius rufo-olivaceus Fungal pigment Rufoolivacin B

Development characteristics and controlling factors of fractures in lacustrine shale and their geological significance for evaluating shale oil sweet spots in the third member of the Shahejie Formation in the Qikou Sag, Bohai Bay Basin

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Petroleum Science 2024年第2期21卷 791-805页

作者： Xu Zeng Tao Yang jian-Wei Feng Cong-Sheng Bian ming Guan Wei Liu Bing-Cheng Guo jin Dong Research Institute of Petroleum Exploration and Development China National Petroleum CorporationBeijing100083China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China School of Earth Sciences China University of PetroleumQingdao266400ShandongChina

Natural fractures are critical for shale oil and gas enrichment and development. Due to the extremely high heterogeneity of shale, the factors controlling the formation of internal fractures, especially horizontal fractures, remain controversial. In this study, we integrate thin section analysis and microcomputed tomography(CT) data from several lacustrine shale samples from the third member(Es3) of the Shahejie Formation, Qikou Sag, Bohai Bay Basin, to assess the fractures in detail. The goal is to reveal the development characteristics, controlling factors, and geological significance for evaluating sweet spots in a shale oil play. The fractures in the Es3contain high-angle structural and horizontal bed-parallel fractures that are mostly shear and extensional. Various factors influence fracture development,including lithofacies, mineral composition, organic matter content, and the number of laminae. Structural fractures occur predominantly in siltstone, whereas bed-parallel fractures are abundant in laminated shale and layered mudstone. A higher quartz content results in higher shale brittleness, causing fractures, whereas the transformation between clay minerals contributes to the development of bedparallel fractures. Excess pore pressure due to hydrocarbon generation and expulsion during thermal advance can cause the formation of bed-parallel fractures. The density of the bed-parallel and structural fractures increases with the lamina density, and the bed-parallel fractures are more sensitive to the number of laminae. The fractures are critical storage spaces and flow conduits and are indicative of sweet spots. The laminated shale in the Es3with a high organic matter content contains natural fractures and is an organic-rich, liquid-rich, self-sourced shale play. Conversely, the siltstone, massive mudstone, and argillaceous carbonate lithofacies contain lower amounts of organic matter and do not have bed-parallel fractures. However, good reservoirs can form in th

关键词： Fractures Development characteristics Controlling factors Shale oil Sweet spot

Melting and floating processes of inorganic materials in molten steel:Visualization physical simulation and mathematical modelling

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China Foundry 2023年第2期20卷 89-98页

作者： jin-hu Lai Sheng Yu Yang-jian Xu Dan-qing jiang San-san Shuai jiang Wang Zhong-ming Ren State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringShanghai UniversityShanghai 200444China Shaoxing Institute of Technology Shanghai UniversityShaoxing 312000ZhejiangChina

It has been demonstrated that heat absorption method by using the inorganic material rod to cool the molten steel can significantly reduce the macrosegregation level of the large steel ***,owing to the opacity of the molten steel,the physical mechanism of the heat absorption method is not *** this work,a transparent hydraulic physical model with water and paraffin wax was built to simulate the melting and floating processes of inorganic materials in the molten steel.A mathematical simulation was also carried out to analyze the connection between the actual ingot and the physical *** show that it is feasible to simulate the molten steel and inorganic materials with water and paraffin *** the help of the physical model,the process of the melting of paraffin wax and its floating to the surface of water were clearly observed,during which the temperature of water at some characteristic positions in the mold was *** visualization findings demonstrate that the melting and floating processes of paraffin wax can help to bring the heat from the center of the mold to the top surface more quickly,which reduces the superheat and significantly accelerates the cooling rate of *** experimental results show that for the water with a certain superheat,the use of a larger mass of paraffin wax can accelerate the cooling of the water,but there is a risk of incomplete melting of the paraffin wax.A higher superheat of water will lead to a quicker melting rate for a given mass of paraffin wax,while a lower superheat leads to the incomplete melting of paraffin wax as well.

关键词： water and paraffin wax heat absorption method physical simulation superheat large steel ingot

Microstructure characteristics of Ni/WC composite cladding coatings

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International Journal of Minerals,Metallurgy and Materials 2016年第2期23卷 184-192页

作者： Gui-rong Yang Chao-peng Huang Wen-ming Song jian Li jin-jun Lu Ying Ma and Yuan Hao State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou 730050China Lanzhou Petroleum Machinery Institute Lanzhou 730000China Wuhan Research Institute of Materials Protection Wuhan 430030China College of Chemistry and Materials Science Northwest UniversityXi'an 710069China

A multilayer tungsten carbide particle（WCp）-reinforced Ni-based alloy coating was fabricated on a steel substrate using vacuum cladding *** morphology,microstructure,and formation mechanism of the coating were studied and discussed in different *** microstructure morphology and phase composition were investigated by scanning electron microscopy,optical microscopy,X-ray diffraction,and energy-dispersive X-ray *** the results,the coating presents a dense and homogeneous microstructure with few pores and is free from *** whole coating shows a multilayer structure,including composite,transition,fusion,and diffusion-affected *** bonding was achieved between the coating and substrate because of the formation of the fusion and diffusion-affected *** Ni-based alloy is mainly composed of y-Ni solid solution with finely dispersed Cr7C3/Cr（23）C6,CrB,and Ni＋*** particles in the composite layer distribute evenly in areas among initial Ni-based alloying particles,forming a special three-dimensional reticular *** macrohardness of the coating is HRC 55,which is remarkably improved compared to that of the *** microhardness increases gradually from the substrate to the composite zone,whereas the microhardness remains almost unchanged in the transition and composite zones.

关键词： cladding composite coatings microstructure characteristics formation mechanisms hardness

X-ray Flashes from Off-axis Nonuniform Jets

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Chinese Journal of Astronomy and Astrophysics 2004年第5期4卷 473-480页

作者： Zhi-Ping jin Da-ming Wei Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008 National Astronomical Observatories Chinese Academy of SciencesBeijing 100012

It has been widely believed that the outflows in gamma-ray bursts are jetted and some jets may have structures like ∈(θ)∝θ-k. We check the possibility that X-ray flashes come from such jets. Both qualitative and quantitative analyses have shown that this model can reproduce most of the observational features of both X-ray flashes and gamma-ray bursts. Using the usual parameters of gamma-ray bursts, we have carried out numerical calculations for both uniform and nonuniform jets, of their fluxes, spectra and peak energies. It seems that nonuniform jets are more appropriate to these observational properties than uniform jets. We have also shown that in our model the observational ratio of gamma-ray bursts to X-ray flashes is about a few units.

关键词： X-rays general-gamma rays bursts-ISM jets and outflows

Orientation variation along growth direction of millimeter free-standing CVD diamond thinned by mechanical grinding

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International Journal of Minerals,Metallurgy and Materials 2014年第8期21卷 839-844页

作者： Xing-kai Wen Jun-jun Wei jin-long Liu jian-chao Guo Liang-xian Chen Cheng-ming Li Institute of Advanced Materials and Technology University of Science and Technology Beijing

A free-standing diamond film with millimeter thickness prepared by DC arc plasma jet was thinned successively by mechanical grinding. The orientation and quality of the diamond films with different thicknesses were characterized by X-ray diffraction and Raman spectroscopy, respectively. The results show a random grain-orientatinn distribution during the initial growth stage. As the film thickness increases, the preferred orientation of the diamond film changes from （111） to （220）, due to the competitive growth mechanism. Twinning generated during the nucleation stage appears to stabilize the preferential growth along the 〈110〉 direction. The interplanar spacing of the （220） plane is enlarged as the film thickness increases, which is caused by the increase of non-diamond-phase carbon and impurities under the cyclic gas. In addition, the quality of the diamond film is barely degraded during the growth process. Furthermore, the peak shift demonstrates a significant inhomogeneity of stress along the film growth direction, which results from competitive growth.

关键词： diamond films chemical vapor deposition grinding orientation growth mechanisms quality