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Statistical Property and Model for the Inter-Event Time of Terrorism Attacks

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Chinese Physics Letters 2010年第6期27卷 273-276页

作者： ZHU Jun-Fang HAN xiao-pu WANG Bing-Hong Department of Modern Physics University of Science and Technology of China Hefei 230026 Institute of Complex Adaptive Systems Shanghai Academy of System Science Shanghai 200093

The inter-event time of terrorism attack events is investigated by empirical data and model analysis. Empirical evidence shows that it follows a scale-free property. In order to understand the dynamic mechanism of such a statistical feature, an opinion dynamic model with a memory effect is proposed on a two-dimensional lattice network. The model mainly highlights the role of individual social conformity and self-affirmation psychology. An attack event occurs when the order parameter indicating the strength of public opposition opinion is smaller than a critical value. Ultimately, the model can reproduce the same statistical property as the empirical data and gives a good understanding for the possible dynamic mechanism of terrorism attacks.

关键词： Data Mechanics Mechanization Models Property Properties

New hydrous phases in the Al_(2)O_(3)-SiO_(2)-H_(2)O system under the mantle transition zone conditions

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Science China Earth Sciences 2023年第4期66卷 730-737页

作者： Baoyun WANG Jin LIU Suyu FU pu xiao Li LI Xing DING Wansheng xiao College of Material and Chemical Engineering Tongren UniversityTongren 554300China Center for High Pressure Science and Technology Advanced Research(HPSTAR) Beijing 100193China Department of Earth and Planetary Science the University of TokyoTokyo 1130033Japan State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

Hydrous minerals in the subducting slabs are potential water carriers into the deep mantle,and thus the synthesis of new hydrous phases is significant in our understanding of water circulation throughout the Earth’s *** this study,we report the two new hydrous phases,Al_(2)SiO_(6)H_(2)and Al_(5.5)Si_(4)O_(18)H_(3.5)(hereafter referred to simply as phases Psi and Phi,respectively),which are synthesized in the Al_(2)O_(3)-SiO_(2)-H_(2)O system at 15.5 GPa,1400℃and 17.5 GPa,1600℃ by using Sakura2500-ton multi-anvil *** luminescence spectra of Cr3+show the phase Psi has characteristic peaks at 687,693 and705 nm,while phase Phi has characteristic peaks at 691,696 and 708 ***-crystal X-ray diffraction (SCXRD) refinements yield a monoclinic structure of both phases (space group P2_(1)) with ideal chemical formulae of Al_(2)SiO6H2and *** determined lattice parameters for phase Psi are a=9.4168±0.0016Å,b=4.3441±0.0007Å,c=9.4360±0.002Åand β=119.726±0.005°at ambient pressure and 300 K,while the phase Phi has a=7.2549±0.0018Å,b=4.3144±0.001Å,c=8.0520±0.002Å,and β=101.740±0.009°at ambient pressure and 250 *** microprobe analyses (EPMA) show the chemical compositions of phases Psi and Phi to be Al_(1.99)Si_(0.85)O_(6)H_(2.62)and Al_(5.58)Si_(2.81)O_(18)H_(8.03),respectively,which slightly deviate from the ideal formulae inferred from SCXRD *** may result from the disorder or substitution of Al and Si by H in the crystal structures under our synthesis *** study suggests that phases Psi and Phi are the two potential water carriers at the upper part of the mantle transitions zone,providing new insights into how deep water is stored in this region.

关键词： New hydrous phases Mantle transition zone Al_(2)O_(3)-SiO_(2)-H_(2)O system Al_(2)SiO_(6)H_(2) Al_(5.5)Si_(4)O_(18)H_(3.5)

Investigation on microscopic invasion characteristics and retention mechanism of fracturing fluid in fractured porous media

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Petroleum Science 2022年第4期19卷 1745-1756页

作者： Qi-An Da Chuan-Jin Yao Xue Zhang xiao-pu Wang xiao-Huan Qu Guang-Lun Lei Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao266580ShandongPeople's Republicof China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPeople's Republic of China Shandong Key Laboratory of Oilfield Chemistry China University of Petroleum(East China)Qingdao266580ShandongPeople's Republic of China

Reservoir damage caused by guar gum fracturing fluid and slick water seriously affects the subsequent oil and gas production. However, the invasion characteristics and retention mechanisms of fracturing fluids in the fracture-matrix zone are still unclear. In this work, a microscopic model reflecting the characteristics of the fracture-matrix zone was designed. Based on the microfluidic experimental method, the process of fracturing fluid invasion, flowback and retention in the fracture-matrix zone was investigated visually and characterized quantitatively. The factors and mechanisms affecting fracturing fluid retention in the fracture-matrix zone were analyzed and clarified. The results indicated that in the invasion process, the frontal swept range of slick water was larger than that of the guar gum fracturing fluid, and the oil displacement efficiency and damage rate were lower than those of the guar gum fracturing fluid under the same invasion pressure. With the increase in invasion pressure, the damage rate of slick water increased from 61.09% to 82.77%, and that of the guar gum fracturing fluid decreased from 93.45% to83.36%. Before subsequent oil production, the invaded fracturing fluid was mainly concentrated in the medium-high permeability area of the fracture-matrix zone. The main resistance of slick water was capillary force, while that of the guar fracturing fluid was mainly viscous resistance. The fracturing fluid retention was most serious in the low permeability region and the region near the end of the *** experimental and numerical simulation results showed that increasing the production pressure difference could improve the velocity field distribution of the fracture-matrix zone, increase the flowback swept range and finally reduce the retention rate of the fracture fluid. The retention mechanisms of slick water in the fracture-matrix zone include emulsion retention and flow field retention, while those of the guar gum fracturing fluid inc

关键词： Microfluidic experiment Reservoir damage Fracturing fluid Fracture-matrix zone Retention mechanism

Exact Solution of the Gyration Radius of an Individual's Trajectory for a Simplified Human Regular Mobility Model

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Chinese Physics Letters 2011年第12期28卷 63-66页

作者： YAN xiao-Yong HAN xiao-pu ZHOU Tao WANG Bing-Hong Department of Transportation Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043 Department of Modern Physics University of Science and Technology of ChinaHefei 230026 Web Sciences Center University of Electronic Science and Technology of ChinaChengdu 610054

We propose a simplified human regular mobility model to simulate an individual's daily travel with three sequential activities:commuting to workplace,going to do leisure activities and returning *** the assumption that the individual has a constant travel speed and inferior limit of time at home and in work,we prove that the daily moving area of an individual is an ellipse,and finally obtain an exact solution of the gyration *** analytical solution captures the empirical observation well.

关键词： Regular simplified finally

Characterization of phosphorus species and modeling for its organic forms in eutrophic shallow lake sediments, North China

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Frontiers of Environmental Science & Engineering 2014年第6期8卷 905-921页

作者： Hongguang CHENG xiao pu Yiting CHEN Fanghua HAO Liming DONG School of Environment Beijing Normal University Beijing 100875 China State Key Laboratory of Remote Sensing Science School of Geography Beijing Normal University Beijing 100875 China

Variations of phosphorus （P） and its species in surface sediment of Baiyangdian Lake, a eutrophic shallow lake located in North China, were investigated through combination of field survey and numerical calculation based on cluster analysis. P fractionation was performed by a sequential extraction scheme, categorized as loosely bound P （NH4Cl-P）, reductant soluble P （BD-P）, metallic oxide bound P （NaOH-P）, calcium bound P （HCl-P） and organic P （Org-P）. P concentrations exhibited regional similarities and a total of four sub-areas were identified in which the same rank was HCl-P 〉 Org-P 〉 BD-P ,=NaOH-P 〉NH4Cl-E NH4Cl-P, BD-P and Org-P were found to contribute to P enrichment in overlying water column. Specifically, labile Org-P acted as a potential pool with a greater contribution in aerobic layer compared to anaerobic layer. A hysteresis （lag = 4 months） existed when labile Org-P concentration was negatively correlated with aerobic layer thickness. In view of magnitude of identified P contributors in sub-areas, higher potential of P release was present in Fuhe River and Tang River estuary areas. On the basis of calibration and verification, the mathematical model with parameter settings applied in this study was improved to serve as a tool for limnology management and eutrophic control.

关键词： phosphorus fractionation variation characteristics modeling sediment Baiyangdian Lake

Advantage of populous countries in the trends of innovation efficiency

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Chinese Physics B 2022年第6期31卷 65-73页

作者： Dan-Dan Hu Xue-Jin Fang xiao-pu Han 2 1Alibaba Research Center for Complexity SciencesHangzhou Normal UniversityHangzhou 311121China Institute of Information Economy and Alibaba Business School Hangzhou Normal UniversityHangzhou 311121China

A flurry of studies indicates that population size has a positive effect on innovation,however,cross-country empirical evidence remains *** this paper,we add to the literature by investigating the relationship between population size and innovation efficiency at the country level through constructing three relative indexes based on the datasets of patent applications and Research and Development(R&D)*** from previous studies based on absolute innovation indicators,the relative indexes can reflect the core innovation efficiency of economies by excluding the impact from the difference of economic development level,with a view putting all economies into a comparable standard *** all of the three relative indexes,their long-term trends show significant correlations with population size,and the economy with a larger population usually has better and stable performance on the trends of innovation *** addition,we find that there is a critical population size,over which the economy would be more likely to have a spontaneous improvement on innovation *** study provides direct evidence in supporting the population size advantage on the trends of innovation efficiency at the economy level and provides new insight to understand the rapid development of innovation in a few populous countries.

关键词： innovation efficiency population size the relative indexes

public Attitudes Towards Policy Instruments for Congestion Mitigation in Shanghai

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Chinese Journal of Population,Resources and Environment 2008年第3期6卷 40-47页

作者： Chen Hongfeng xiao pu Feng Xiangzhao Li Fen Anhui Academy of Environmental Sciences Hefei 230061 China Policy Reseach Center for Environment and Economy of MEP Beijing 100029 China Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Congestion causes many externalities for the society, including time delays, excessive fuel consumption, air pollution, noise and safety concerns. In Shanghai, various policy options have been explored, piloted or applied; however, not all of them may be understood and accepted by the public. A survey was conducted to investigate people＇s attitudes towards several policy options. The main findings reveal that Shanghai residents are resistant to certain policies, such as congestion charges, higher parking charges in congested areas and car restrictions. Instead, they favor public transport provisions. The paper suggests that there is a case for promoting public transport and more efficient trips when the car ownership is still low, and for investing in a policy of educating the public on the ＇true＇ costs and causes of congestion before embarking on ,an intensive policy of congestion charges or restrictions.

关键词： traffic congestion travel demand management car ownership attitude survey

Game theoretic analysis of environmental impact assessment system in China

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Frontiers of Environmental Science & Engineering 2007年第4期1卷 448-453页

作者： CHENG Hongguang QI Ye pu xiao GONG Li School of Environment Beijing Normal UniversityBeijing 100875China School of public Policy and Management Tsinghua UniversityBeijing 100084China

Environmental impact assessment(EIA)system has been established in China since *** present EIA cases,there are four participants in general:governments,enterprises,EIA organizations and the *** public has held responsible for both social costs and social *** public supervises social costs produced by enterprises discharging pollutant in *** public participation is mostly deputized by governments,which severely weaken the independence of the public as one participant in *** this paper,EIA refers to the different attitudes of the par-ticipants whose optional strategies may be described by a proper game *** to disfigurements in EIA,three sides(governments,enterprises,and EIA organizations)dynamic iterative game theory of many phases is established referring to iterative game theory,dynamic game theory of incomplete information,and perfect Bayesian equilibrium theory to analyze the reciprocity relation among governments,EIA organizations and *** results show that in a short period,economic benefit is preponderant over social *** and enterprises both do not want to take EIA to reveal social *** organizations’income comes from enterprises and the collusions are built between them to vindicate economic *** a long run,social benefit loss caused by environmental pollution must be recuperated sooner or later and environmental deterioration will influence the achievements of economic benefit,so both governments and enterprises are certain to pursue high social benefit and willing to take EIA,helpful to increase private *** organizations will make fair assessment when their economic benefit are *** present,the public as silent victims can not take actual part in *** EIA system must be improved to break the present equilibrium of three sides,bringing the public to the equilibrium to exert public supervision.

关键词： environmental impact assessment(EIA) three sides dynamic iterative game theory of many phases perfect Bayesian equilibrium

3ranular cell tumor of the urethra： a case report anc iterature review

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Asian Journal of Andrology 2016年第6期18卷 946-948页

作者： Chun-xiao pu Liang Gao Yun-Jin Bai Ping Han Department of Urology West China Hospital Sichuan University No. 37 GuoxueXiang Chengdu 610041 China

Dear Editor, Granular cell tumors （GCTs） are uncommon soft tissue neoplasms of unclear origin that most often occur in head and neck regions particularly the tongue. Until now, GCTs of the male genitalia are extremely rare with 〈20 cases reported in the English literature. Although GCTs of the penis, including prepuce, shaft, glans, corona, and corpus cavernosum,1-3 have been reported, this report describes a case of GCT originating from the urethra. To the best of our knowledge, this is the first report of a urethral case in man.

关键词： @@