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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

L^p-L^q Estimates for a Class of Pseudo-Differential Equations and Their Applications

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Acta Mathematica Sinica,English Series 2011年第7期27卷 1435-1448页

作者： Qing quan deng Xiao Hua YAO Department of Mathematics Huazhong Normal University Wuhan 430079 P. R. China

This paper is concerned with the L^p-L^q estimates of the solutions for a class of pseudodifferential equations under some suitable degenerate assumptions. As applications, these estimates can be used to show that a generalized Schroedinger operator with some integrable potential generates a fractionally integrated group in L^p（R^n）.

关键词： Pseudo-differential equation,L^p-L^q estimate integrated group

On Modeling Drilling Load in Lunar Regolith Simulant

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Chinese Journal of Mechanical Engineering 2018年第1期31卷 41-52页

作者： Qi-quan quan Chong-Bin Chen Zong-quan deng Jun-Yue Tang De-Wei Tang State Key Laboratory of Robotics and System Harbin Institute of Technology

Drilling and coring, as effective ways to obtain lunar regolith along the longitudinal direction, are widely applied in the lunar sampling field. Conventionally, modeling of drill-soil interaction was divided into soil cutting and screw conveyance processes, ignoring the differences in soil mechanical properties between them. To improve the modeling accuracy, a hypothesis that divides the drill-soil interaction into four parts: cuttings screw conveyance, cuttings extruding, cuttings bulldozing, and in situ simulant cutting, is proposed to establish a novel model based on the passive earth pressure theory. An iterative numerical calculation method is developed to predict the drilling loads. A drilling and coring testbed is developed to conduct experimental tests. Drilling experiments indicate that the drilling loads calculated by the proposed model match well the experimental results. The proposed research provides the instructions to adopt a suitable drilling strategy to match the rotary and penetrating motions, to increase the safety and reliability of drilling control in lunar sampling missions.

关键词： Lunar regolith drilling Lunar regolith simulant Drill-simulant interaction Screw conveyance

How Does Debt Structure Influence Stock Price Crash Risk?

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Journal of Systems Science & Complexity 2018年第2期31卷 473-492页

作者： jia Zichao deng Lu XU Ruiyang School of Economics and Management BeiHang University

This paper uses the financial data of Chinese listed firms to explore the relationship between the debt structure, which is measured as the ratio of trade credit to bank loan, and future stock price crash risk. The empirical results show that the ratio of trade credit to bank loan is positively associated with the firm-specific crash risk while a good institutional environment reduces this positive relationship. In addition, considering the firm＇s ownership type, the authors find that the positive relationship between the debt structure and crash risk is more significant in the SOEs.

关键词： Bank loan crash risk debt structure trade credit.

Analysis of blockchain protocol against static adversarial miners corrupted by long delay attackers

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Science China(Information Sciences) 2020年第3期63卷 49-63页

作者： quan YUAN Puwen WEI Keting jia Haiyang XUE Key Laboratory of Cryptologic Technology and Information Security Ministry of EducationShandong University Department of Computer Science and Technology Tsinghua University State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of Sciences Data Assurance and Communication Security Research Center Chinese Academy of Sciences

Bitcoin, which was initially introduced by Nakamoto, is the most disruptive and impactive cryptocurrency. The core Bitcoin technology is the so-called blockchain protocol. In recent years, several studies have focused on rigorous analyses of the security of Nakamoto’s blockchain protocol in an asynchronous network where network delay must be considered. Wei, Yuan, and Zheng investigated the effect of a long delay attack against Nakamoto’s blockchain protocol. However, their proof only holds in the honest miner setting. In this study, we improve Wei, Yuan and Zheng’s result using a stronger model where the adversary can perform long delay attacks and corrupt a certain fraction of the miners. We propose a method to analyze the converge event and demonstrate that the properties of chain growth, common prefix, and chain quality still hold with reasonable parameters in our stronger model.

关键词： blockchain bitcoin random oracle delay consensus protocol

Deployment analysis of composite thin-walled lenticular tubes with effect of storage time and temperature

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Chinese Journal of Aeronautics 2024年第1期37卷 162-172页

作者： Jinfeng deng Ning AN Qilong jia Xiaofei MA School of Aeronautics and Astronautics Sichuan UniversityChengdu 610065China State Key Laboratory for Strength and Vibration of Mechanical Structures School of AerospaceXi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024China Xi’an Institute of Space Radio Technology Xi’an 710100China

Composite Thin-walled Lenticular Tube(CTLT)is increasingly utilized in small satellites missions as a lightweight,foldable,and rollable structural material that facilitates the construction of large deployable *** CTLT is initially flattened and coiled around a central hub for storage before launch,during which elastic energy is stored as deformation energy,allowing it to be self-deployed on demand for use in *** work presents a comprehensive investigation into the coiling,storage and deployment behaviors of CTLT that wraps around a central hub.A nonlinear explicit dynamic finite element model was developed with both deformable CTLT and rigidbodies mechanisms including the central hub and guide rollers,as well as the complex interactions among *** coiling mechanics characteristics such as stored strain energy and rotational moment were presented and validated against experimental data in the ***,the dynamic deployment behaviors were analyzed in terms of two different deployment methods,namely,controlled deployment and free *** effect of material property change during storage was also discussed through numerical experiments.

关键词： Composite deployable structures Deployment dynamics Finite element method Stress relaxation Thin-walled booms

Long-term oscillation of drought conditions in the western China： an analysis of PDSI on a decadal scale

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Journal of Arid Land 2016年第6期8卷 819-831页

作者： JIN jia WANG quan LI Lanhai Joint Research Center of Drylands Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China University of Chinese Academy of Sciences Beijing 100049 China Graduate School of Agriculture Shizuoka University Shizuoka 422-8529 Japan

Water resource availability is one of the primary limiting factors with regard to ecosystems in the western China. Having a clear understanding of multi-scale drought patterns in this region is a key step for adaption and mitigation to climate change. The Palmer drought severity index （PDSI） is a widely applied index to assess drought conditions. In this study, long-term monthly self-calibrated PDSI data from 1951 to 2012 were examined for drought spatiotemporal variations in the western China. The results clearly indicated that apparent spatial heterogeneities were evidenced between two sub-regions （arid land with annual precipitation less than 200 mm and semiarid land with annual precipitation between 200 to 500 mm） as well as in the entire region of the western China. Ensemble empirical mode decomposition （EEMD） analyses on monthly PDSI and other atmospheric variable time-series obtained from the Department of Civil and Environmental Engineering, Princeton University revealed that all monthly time-series of variables could be completely decomposed into eight intrinsic mode functions （IMFs） and a trend （residual）. This indicates that the monthly PDSI and atmospheric variables of the semiarid area in the western China contain eight quasi-period oscillations on various timescale spanning, seasonal to decadal cycles and a trend of a larger timescale from 1951-2012. The multi-scale drought patterns identified in this research could be powerful supports for decision-making regarding coping with droughts in this region.

关键词： decadal scale EEMD PDSI arid land semiarid land

FAST RECONSTRUCTION METHOD BASED ON COMMON UNIFIED DEVICE ARCHITECTURE(CUDA)FOR MICRO-CT

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Journal of Innovative Optical Health Sciences 2010年第1期3卷 39-43页

作者： GUOTAO quan TANGYOU SUN YONG deng Britton Chance Center for Biomedical Photonics Wuhan National Laboratory for Optoelectronics—Huazhong University of Science and Technology Wuhan 430074 P.R.China

Three-dimensional image reconstruction with Feldkamp,Davis,and Kress(FDK)algorithm is the most time consuming part in *** parallel algorithm based on the computer cluster is capable of accelerating image reconstruction speed;however,the hardware is very *** this paper,using the most current graphics processing units(GPU),we present a method based on common unified device architecture(CUDA)for speeding up the Micro-CT image reconstruction *** most time consuming filtering and back-projection parts of the FDK algorithm are parallelized for the CUDA *** CUDA-based reconstruction speed and image qualities are compared with CPU results for the projecting data of the Micro-CT *** results show that the 3D image reconstruction speed based on CUDA is ten times faster than the speed with *** conclusion the FDK algorithm based on CUDA for Micro-CT can reconstruct the 3D image right after the end of data acquisition.

关键词： Micro-CT FDK CUDA GPU

Preventing and localizing esophagogastric anastomosis leakage by sleeve-wrapping of the pedicled omentum

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World Journal of Gastroenterology 2014年第43期20卷 16282-16286页

作者： quan-Xing Liu Xu-Feng deng Bing Hou jia-Xin Min Ji-Gang Dai Department of Thoracic Surgery Xinqiao HospitalThird Military Medical University

AIM: To develop a technique of sleeve-wrapping the pedicled omentum around the esophagogastric anastomosis for preventing and localizing leakage.

关键词： Anastomotic leakage Esophageal cancer Esophagectomy Esophagogastrostomy Pedicled omentum