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Some Analytical Properties of the Model for Stochastic Evolutionary Games in Finite Populations with Non-uniform Interaction Rate

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Communications in Theoretical Physics 2013年第7期60卷 37-47页

作者： quan ji WANG Xian-jia GuangDong Electric Power Design Institute China Energy Engineering Group Co. Ltd Guangzhou 510663 China Department of Management and Economics Tianjin University Tianjin 300072 China Institute of Systems Engineering Wuhan University Wuhan 430072 China School of Economics and Management Wuhan University Wuhan 430072 China

Traditional evolutionary games assume uniform interaction rate, which means that the rate at which individuals meet and interact is independent of their strategies. But in some systems, especially biological systems, the players interact with each other discriminately. Taylor and Nowak (2006) were the first to establish the corresponding non-uniform interaction rate model by allowing the interaction rates to depend on strategies. Their model is based on replicator dynamics which assumes an infinite size population. But in reality, the number of individuals in the population is always finite, and there will be some random interference in the individuals' strategy selection process. Therefore, it is more practical to establish the corresponding stochastic evolutionary model in finite populations. In fact, the analysis of evolutionary games in a finite size population is more difficult. Just as Taylor and Nowak said in the outlook section of their paper, 'The analysis of non-uniform interaction rates should be extended to stochastic game dynamics of finite populations.' In this paper, we are exactly doing this work. We extend Taylor and Nowak's model from infinite to finite case, especially focusing on the influence of non-uniform connection characteristics on the evolutionary stable state of the system. We model the strategy evolutionary process of the population by a continuous ergodic Markov process. Based on the limit distribution of the process, we can give the evolutionary stable state of the system. We make a complete classification of the symmetric 2×2 games. For each case game, the corresponding limit distribution of the Markov-based process is given when noise intensity is small enough. In contrast with most literatures in evolutionary games using the simulation method, all our results obtained are analytical. Especially, in the dominant-case game, coexistence of the two strategies may become evolutionary stable states in our model. This result can be used to

关键词： stochastic evolutionary games non-uniform interaction rate finite population evolutionary stablestate

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Control Strategy of a Two-Lap Connection Converter

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Journal of China University of Mining and Technology 2007年第3期17卷 436-440页

作者： quan ji-nan WANG Cong School of Mechanical Electronic and Information China University of Mining ＆ Technology Beijing 100083 China Heilongjiang Institute of Science and Technology Harbin Heilongjiang 150027 China

Two-lap sequential control converters are usually adopted to supply and improve the power factor of input side. The line harmonic damage generated by a sequential control thyristor converter can be serious. To solve this prob-lem and seek an optimum control strategy,we derived the changeable regular of the line-input-current,the fundamen-tal-frequency-current,the harmonic-current-content and the harmonic total distortion ratio of the converter at different firing angles. We obtained relevant data from experiments with a sequential control system of a DC 2.2kW/220V motor. With the example of the operating condition of a DC mine elevator,the harmonic current is two times approximately in sequential control compared to synchronous control when the firing angle of the two converters differs in 30°. At dif-ferent operating states of a two-lap connection converter,the ideal strategy is an exchange between sequential control and synchronous control,by which we can achieve the complementary goal of improving the power factor and har-monic effect. All analytical conclusions are supported by simulation and experimental results.

关键词： sequential control synchronous control harmonic current mine elevator

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Texture-based magnetostriction calculation of oriented polycrystalline cobalt ferrites

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Rare Metals 2018年第5期37卷 421-426页

作者： ji-quan Wang ji-Heng Li Chao Yuan Xiao-Qian Bao Xue-Xu Gao State Key Laboratory of Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083China

Oriented polycrystalline cobalt ferrites with different alignments were prepared via a ceramic method. The maximum magnetostriction λs up to -270×10^-6 was achieved for oriented samples, when the oriented magnetic field was above 1.0 T. Textures of all samples were determined by electron back-scattered diffraction （EBSD） technique and were used to calculate magnetostriction values of oriented polycrystalline cobalt ferrite samples. Results show that a preferred 〈001〉 orientation has been obtained within oriented sample. Calculation was done by considering the magnetostriction value as the sum of the content in volume fraction-weighted single-crystal behavior along [100], [110], [210], [310], [311], [211] and [111] directions. The calculated magnetostriction values when compared with experimentally obtained values show identical behavior as a function of applied magnetization orientation field. Good consistency of change rules between calculated values and measured ones illustrates the successful application of this method in predicting magnetostriction values of polycrystalline materials.

关键词： Magnetostriction calculation Oriented polycrystalline Cobalt ferrites Texture

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Evaluation of oasis ecosystem risk by reliability theory in an arid area: A case study in the Shiyang River Basin, China

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Journal of Environmental Sciences 2007年第4期19卷 508-512页

作者： LI Wei-de LI Zi-zhen WANG ji-quan Institute of Bioinformatics School of Mathematics and Statistics Lanzhou University Lanzhou 730000 China. Key Laboratory of Arid and Pastoral Agroecology of the Ministry of Education Lanzhou University Lanzhou 730000 China Institite of Cold and Arid Regions Environment and Engineering Chinese Academy of Sciences Lanzhou 730000 China

Ecosystem risk is a new concept in understanding environmental problems. It is important to study and develop quantitative methods for regional ecosystem risk analysis. In this study, some new indicators and methods for measuring oasis ecosystem risk were established using reliability theory. These indicators are linked to water resource, which is the key restricting factor in arid area oasis ecosystems. They have clear meanings and can also be compared in different arid area oases. A case study in the Liangzhou oasis of the Shiyang River Basin in China shows how to calculate these ecosystem risk indicators. The results of the case study are as follows： the reliability indicator, risk indicator, stability indicator, and integrated loss indicator of the Liangzhou oasis are 0.686, 0.314, 0.743, and 0.301, respectively. This means that the reliability degree of the oasis＇s ecosystem safety is 68.6%; the degree of risk that it is unsafe is 31.4%; the stability degree is 74.3%; and 30.1% of the oasis＇s area is supported by over-exploiting underground water and damaging the lower reaches of the ecosystem. This result can be used as a guide in controlling and managing ecosystem risk in the research area.

关键词： ecosystem risk sustainable development Shiyang River Basin risk analysis

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Giant Monopole Resonance with Boltzmann-Nordheim-Vlasov Model

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Chinese Physics Letters 1996年第10期13卷 724-726页

作者： WEN Wan-xin ZHONG ji-quan jiN Gen-ming Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000 CCAST(World Laboratory) P.O.Box 8730Beijing 100080

The Boltzmann-Nordheim-Vlasov (BNV) model was employed to investigate the giant monopole resonance (GMR) built on very excited residula nuclei formed in heavy-ion collisions. Roughly speaking the GMR energy of BNV model is very similar to the value given by the empirical formual EGMR = 31.2A^(-l/3) + 20.6A^(-l/6) and hardly changes with impact parameter and bombarding energy.

关键词： energy. excited Boltzmann

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Geographical Information System-Based Assessment of Ecological Security in Changbai Mountain Region

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Journal of Mountain Science 2014年第1期11卷 86-97页

作者： LU Xing-chang ZHANG ji-quan LI Xiao-zhen School of Environment Northeast Normal University College of Geo-exploration Science & Technology Jilin University Anyang City Bureau of Agriculture

Ecological security defined as the creation of a condition where the physical surroundings of a community provide for the needs of its inhabitants without diminishing its natural stock,which is important for regional security and social *** recent years,land use patterns in the Changbai Mountain region have changed significantly with intensive human activities,and consequently led to increasing problems in regional ecological *** on the Pressure-State-Impact-Response(PSIR) model and the mathematical method of catastrophe progression supported by geographical information system(GIS),the ecological security situation of the study area under land use and cover change(LUCC) was *** results indicated that the ecological security in Changbai Mountain region varied nonlinearly,which got better from 1990 to 2000 but became worse from 2000 to 2007,the ecological security levels in Changbai Mountain region were mainly medium and medium to low during the past 17 years,with higher values of Ecological Security Index(ESI) in the central region and lower values in the east and west,the ecological security situation was more serious in the settlements and river valleys,where the LUCC was most remarkable.

关键词： Ecological security Pressure-State-Impact-Response Land use and cover change Geographical Information System(GIS) Catastrophe progression Changbai Mountain

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Ultra-low-carbon steel spheroidization and torsion

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Journal of Iron and Steel Research International 2018年第9期25卷 968-974页

作者： Yan-jun Yin ji-quan Sun Ai-min Zhao jin Gou Institute of Engineering Technology University of Science and Technology Beijing Beijing 100083 China Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083 China

Spheroidizing annealing and torsion testing of 0.027 wt% carbon steel rod were conducted to evaluate spheroidization kinetic behavior at 943 K （670 ℃） under deformed and non-deformed states. Kinetic curves were also predicted using the Johnson-Mehl-Avrami-Kolmogorov equation, and the results agree well with the experimental ones. After spheroidization was performed twice, the spherical cementite and precipitated carbides became smaller and the distribution was more uniform. Comparison of materials subjected to single and double spheroidizing annealing indicated a difference in grain size. Torsion performance was considerably improved under double spheroidization, especially the maximum torque with slight variations.

关键词： Ultra-low-carbon steel Spheroidization Spheroidization kinetic Torsion property

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Single gate optimization for plastic injection mold

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第7期8卷 1077-1083页

作者： LI ji-quan LI De-qun GUO Zhi-ying LV Hai-yuan Department of Plasticity Technology Shanghai Jiao Tong University Shanghai 200030 China

This paper deals with a methodology for single gate location optimization for plastic injection mold. The objective of the gate optimization is to minimize the warpage of injection molded parts, because warpage is a crucial quality issue for most injection molded parts while it is influenced greatly by the gate location. Feature warpage is defined as the ratio of maximum displacement on the feature surface to the projected length of the feature surface to describe part warpage. The optimization is combined with the numerical simulation technology to find the optimal gate location, in which the simulated annealing algorithm is used to search for the optimum. Finally, an example is discussed in the paper and it can be concluded that the proposed method is effective.

关键词： Injection mold Gate location Optimization Feature warpage

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Design of the upstream decay pipe window of the long baseline neutrino facility

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Nuclear Science and Techniques 2021年第11期32卷 134-145页

作者： Hai-jing Wang Ye Yuan jing-Yu Tang quan ji Ling Kang Chang-Jun Ning ji-Lei Sun Shao-Hong Wei Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

The beam windows of high-energy beam lines are important,and it is sometimes difficult to design because it is necessary to ensure particle propagation with minimum disturbance and fulfill mechanical requirements at the same *** upstream decay pipe window of the long baseline neutrino facility at Fermilab has an extremely large diameter(1.8 m),with a thickness of only 1.5 mm to separate the helium atmosphere in the decay pipe and the nitrogen atmosphere on the other ***,the center of this dish-shaped window is expected to be a200-mm-diameter beryllium dish welded to the outside aluminum alloy A6061,and this welded combination must withstand extreme conditions of a 2.4-MW,high-energy proton beam without *** severe conditions make the design of this window an unprecedented *** paper describes the static thermal-structural analyses based on which the structure has been optimized,as well as dynamic analyses for understanding the shockwave effects originating in the *** optimization,the maximum von Mises stresses in the window decreased significantly in both normal operation and accident cases,making our design very reasonable.

关键词： Decay pipe window Structure optimization Dynamic analyses Long baseline neutrino facility

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EVALUATION OF ORAL MIDAZOLAM AS CONSCIOUS SEDATION FOR PEDIATRIC PATIENTS IN ORAL RESTORATION

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Chinese Medical Sciences Journal 2006年第3期21卷 163-166页

作者： Kuo Wan quan jing ji-zhi Zhao Department of Endodontics Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730

Objective To evaluate the effect of midazolam alone on sedation in young children for dental restorative care. Methods Forty children, aged 5 to 10 years with a mean age of 7.3 years, participated in this study. Twenty-one patients were assigned to intervention group received 0. 5 mg/kg of oral midazolam 20 minutes prior to the beginning of dental treatment, and 19 patients in control group received placebo liquid 20 minutes before treatment. All patients received painless local anesthetic injection and were restrained with children＇s board and bands. Blood pressure （ BP）, heart rate （HR）, oxygen saturation, treatment compliance scores of the Ramsay scale, the Briekopf and Butmer scale, Frankl scale, and the Houpt scale were recorded. Each procedure was taped and all the data were evaluated every 5 minutes by an anesthetist or experienced dentist who was unaware of the drug given to the child. Results HR in intervention group （82. 5 ± 5.1 bpm） was much lower than that in control group （95.2 ± 8.9 bpm; F=31.20, P 〈0. 001 ）. Intervention group had a significantly lower systolic BP level （94.8±5.6 mmHg） than control group （98.5±5.5 mm Hg; F=4. 34, P =0. 04）, but the diastolic BP （63.0 ± 3.5 mm Hg） was not significantly lower than control group （ 65.5 ± 4. 8 mm Hg; F = 3.31, P = 0. 07 ）. Children in intervention group showed more compliance. The patients＇ scores of the Ramsay scale, Briekopf and Buttner scale, Frankl scale, and Houpt scale in intervention group （ 1.37 ± 0. 96, 1.37 ± 0. 83, 1.32 ± 0. 67, and 2. 32 ± 1.49, respectively） were significantly lower than those in control group （3.71 ± 1.23, 2.71 ± 0. 96, 2.71 ± 0. 90, and 4.71 ± 1.19 ; F = 44. 66, 22. 36, 30.39,and 31.88,respectively,all P〈0.001） Conclusions Oral midazolam alone is safe and produces effective sedation for the dental treatment of young children. Oral midazolam application should be generally preferred because it is more easily accepted by pediatric patients.

关键词： midazolam oral administration dental anxiety dental restoration

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