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Fitness of others'evaluation effect promotes cooperation in spatial public goods game

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Chinese Physics B 2021年第12期30卷 648-655页

作者： Jian-Wei wang Rong wang Feng-Yuan Yu School of Business Administration Northeastern UniversityShenyang 110819China

Payoff-driven strategy updating rule has always been adopted as a classic mechanism,but up to now,there have been a great many of researches on considering other forms of strategy updating rules,among which pursuing high fitness is one of the most direct and conventional motivations in the decision-making using game *** there are few or no researches on fitness from the perspective of others'*** view of this,we propose a new model in which the evaluation effect with fitness-driven strategy updating rule is taken into consideration,and introduce an evaluation coefficient to present the degree of others'evaluation on individual's *** cooperative individuals can get positive evaluation,otherwise defective individuals get negative evaluation,and the degree of evaluation is related to the number of neighbors who have the same strategy of *** numerical simulation,we find that the evaluation effect of others can enhance the network reciprocity,thus promoting the *** a strong dilemma,the higher evaluation coefficient can greatly weaken the cooperation dilemma;for a weak one,the higher evaluation coefficient can make cooperator clusters spread faster,however,there is no significant difference in the level of cooperation in the final stable state among different evaluation *** cooperation becomes more flourish as the number of fitness-driven individuals increases,when all individuals adopt fitness-driven strategy updating rule,the cooperators can quickly occupy the whole ***,we demonstrate the robustness of the results on the WS small-world network,ER random network,and BA scalefree network.

关键词： public goods game evaluation effect fitness network reciprocity

Effect of deep cryogenic treatment on mechanical behavior of a Cu-Cr-Zr alloy for electrodes of spot welding

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Rare Metals 2005年第4期24卷 392-396页

作者： wang Xiaofeng SHAN Ping HU Shengsun WU Zhisheng wang Xibao School of Material Science and Engineering Tianjin University Tianjin 300072 China

The effects of deep cryogenic treatment on mechanical behavior of a Cu-Cr-Zr alloy for electrodes of spot welding were investigated employing Brinell-hardness testing unit, abrasion examination machine, electronic almighty testing machine and X-ray stress analyzer. Tensile fracture surfaces of the alloy were characterized by scanning electronic microscope （SEM） with energy dispersive X-ray spectroscopy （EDS）. The results showed that, after deep cryogenic treatment, σb and σ0.2 increased 23 MPa and 21 MPa respectively, the wear rate of the alloy exhibited the trend of decrease with the decreasing temperature and increasing time of deep cryogenic treatment, and the surface residual stress of the alloy was partially eliminated by deep cryogenic treatment.

关键词： Cu-Cr-Zr alloy deep cryogenic treatment mechanical properties spot welding electrode

Testing potassium limitation on soil microbial activity in a sub-tropical forest

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Journal of Forestry Research 2019年第6期30卷 2341-2347页

作者： Taiki Mori Senhao wang Zhuohang wang Cong wang Hui Mo Jiangming Mo Xiankai Lu Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems and Guangdong Provincial Key Laboratory of Applied BotanySouth China Botanical GardenChinese Academy of SciencesGuangzhou 510650GuangdongPeople’s Republic of China Graduate School of Agriculture Kyoto UniversityKitashirakawa Oiwake-choSakyo-kuKyotoJapan University of Chinese Academy of Sciences Beijing 100049People’s Republic of China Department of Biological Sciences Stanford UniversityStanfordCA 94305-5020USA Department of Forest Site Environment Forestry and Forest Products Research InstituteTsukubaIbaraki 305-8687Japan

Because potassium(K)is a rock-derived essential element that can be depleted in highly-weathered tropical soils,K availability may limit some portion of soil microbial activity in tropical forest *** this paper we tested if K limits microbial activity in the condition of sufficient labile C *** incubation experiment was performed using surface soil samples(0–10 cm depth)obtained from four permanent ecological research plots in a natural sub-tropical forest in southern *** samples were taken in September *** soil respiration rates and microbial biomass were measured after the addition of glucose(both D and L)with and without K(potassium chloride).We did not observe any effects of K addition on soil microbial respiration,suggesting that K does not limit the microbial activity in the condition of sufficient labile C *** lack of microbial response to added K can be attributed to the high mobility of K in forest ecosystems,which may have provided sufficient K to microbes in our soil samples(already provided at the beginning of the incubation).However,at the present stage,we cannot conclude that K is not a limiting factor of soil microbial activity in other tropical forest ecosystems because of the heterogeneity of tropical forest ecosystems and few *** hypothesis needs to be tested in larger numbers of tropical forests.

关键词： Nutrient limitation Rock-derived nutrients Soil biology Nutrient dynamics Potassium addition

Spray pyrolysis synthesis of nickel-rich layered cathodes LiNi_(1-2x)Co_xMn_xO_2(x = 0.075, 0.05, 0.025) for lithium-ion batteries

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Journal of Energy Chemistry 2018年第2期27卷 447-450页

作者： Yan Li Xinhai Li Zhixing wang Huajun Guo Jiexi wang School of Metallurgy and Environment Central South University

In this study we report a series of nickel-rich layered cathodes LiNi1-2xCoxMnxO2（x = 0.075, 0.05,0.025） prepared from chlorides solution via ultrasonic spray pyrolysis. SEM images illustrate that the samples are submicron-sized particles and the particle sizes increase with the increase of Ni ***0.85Co0.075Mn0.075O2 delivers a discharge capacity of 174.9 mAh g-1 with holding 93% reversible capacity at 1 C after 80 cycles, and can maintain a discharge capacity of 175.3 mAh g-1 at 5 C rate. With increasing Ni content, the initial specific capacity increases while the cycling and rate performance degrades in some extent. These satisfying results demonstrate that spray pyrolysis is a powerful and efficient synthesis technology for producing Ni-rich layered cathode（Ni content 〉 80%）.

关键词： Lithium-ion batteries Nickel-rich layered cathode Ultrasonic spray pyrolysis Powder technology Composite materials

Microstructure and kinetics of hot deformation WE43 magnesium alloy

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Rare Metals 2008年第4期27卷 405-409页

作者： GAO Jiacheng wang Qiang wang Yong LI Wei NIU Wenjuan College of Materials Science and Engineering National Engineering Research Center for Magnesium Alloys Chongqing University Chongqing 400044 China

The effect of compression on the microstructures and flow behavior of WE43 magnesium alloy was investigated in this article. The relationship between flow stress and strain rate was discussed. According to the empirical formula ε = Aδ^n exp （-Q/R T）, the value of heat activation of WE43 magnesium alloys is 297,15 kJ/mol. A mechanism of deformation softening of WE43 alloy in testing hot deformation was identified to be dynamic recrystallization.

关键词： WE43 magnesium alloy hot deformation microstructure kinetics

Frequent and prolonged nocturnal occupation of port areas by Yangtze finless porpoises (Neophocaena asiaeorientalis): Forced choice for feeding?

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Integrative Zoology 2015年第1期10卷 122-132页

作者： Zhitao wang Tomonari AKAMATSU Zhigang MEI Lijun DONG Tomohito IMAIZUMI Kexiong wang Ding wang The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences Institute of Hydrobiology of the Chinese Academy of SciencesWuhanChina University of Chinese Academy of Sciences BeijingChina National Research Institute of Fisheries Engineering IbarakiJapan

During the Yangtze Freshwater Dolphin Expedition 2012,Yangtze finless porpoises(Neophocaena asiaeorientalis)were acoustically monitored in 9 port areas at *** 6566 min of nocturnal monitoring,porpoise sonar was detected for 488 min(7.43%of the total time).Of all 81 encounters,the longest echolocation span obtained was 102.9 min,suggesting frequent and prolonged porpoise occupation of the port areas.A combined total of 2091 click trains were recorded,with 129(6.2%)containing minimum inter-click intervals(ICIs)below 10 ms(termed a buzz).Buzzes with a decrease in ICIs and search and approach phases that resembled feeding echolocation signals accounted for 44.2%(N=52)of all *** with an increase in ICIs,suggesting a mirrored prey capture phase,accounted for 20.2%(N=26)and could reflect attempts to locate escaped prey because they were followed by approach-phase feeding *** evidence of porpoises fleeing the proximity of vessels was *** recordings indicating clusters of porpoises feeding near the port areas suggest a forced choice for feeding due to the relatively higher prey availability in the port areas compared to other areas in the Yangtze River that are probably overfished.

关键词： feeding behavior nocturnal passive acoustic monitoring port area prey availability

The Mechanical and Electrical Properties of the Smart Aggregate Based on the Mixed Cementitious Materials

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Journal of Wuhan University of Technology(Materials Science) 2024年第6期39卷 1528-1533页

作者： wang Haifeng YAN Handong XU Yuye MEI Zhen wang Chen College of Civil Engineering Huaqiao UniversityXiamen 361021China Higher-educational Engineering Research Centre for Intelligence and Automation in Construction of Fujian Province College of Civil EngineeringHuaqiao UniversityXiamen 361021China

Cement and resin were designed as mixed cementitious materials to study the smart aggregate(SA)of smart *** fiber(CF)and surfactant were taken into consideration to adjust the mechanical and electrical properties of smart aggregate(SA)in this *** experimental results indicate that the flexibility and mechanical properties of SA can be improved by using such mixed cementitious *** is shows that,although the compressive strength and flexural strength can be enhanced effectively by using resin and CF,the electrical conductivity decreases significantly,which is because the water molecules are difficult to penetrate through the mixture materials so the hydration reaction of cement can not fully carry ***,the electrical conductivity can be improved by adding the surfactant,and the strength and mechanical electrical properties can be adjusted effectively by the surfactant.

关键词： surfactant carbon fiber electrical property mechanical property smart aggregate

Generating quasi-single-cycle THz pulse from frequency-chirped electron bunch train and a tapered undulator

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High Power Laser Science and Engineering 2016年第1期4卷 5-8页

作者： Zhuoran Ma Zhe wang Feichao Fu Rui wang Dao Xiang Key Laboratory for Laser Plasmas (Ministry of Education) Department of Physics and AstronomyShanghai Jiao Tong University IFSA Collaborative Innovation Center Shanghai Jiao Tong University

We propose a proof-of-principle experiment to test a new scheme to produce a single-cycle radiation pulse in free-electron lasers(FELs). Here, a few α-BBO crystals will be first used to produce an equally spaced laser pulse ***, the laser pulse train illuminates the cathode to produce a frequency-chirped electron bunch train in a photocathode rf gun. Finally, the frequency-chirped electron bunch train passes through a tapered undulator to produce a quasi-single-cycle THz pulse. This experiment should allow comparison and confirmation of predictive models and scaling laws, and the preliminary experimental results will also be discussed.

关键词： electron bunch train single-cycle THz pulse tapered undulator

Effect of different aged cartilage ECM on chondrogenesis of BMSCs in vitro and in vivo

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Regenerative Biomaterials 2020年第6期7卷 583-595页

作者： Xiuyu wang Yan Lu Wan wang Qiguang wang Jie Liang Yujiang Fan Xingdong Zhang Guangxi Engineering Center in Biomedical Materials for Tissue and Organ Regeneration Guangxi Collaborative Innovation Center for BiomedicineGuangxi Medical UniversityNanning 530021China National Engineering Research Center for Biomaterials Sichuan UniversityWangjiang Road 29Chengdu 610064China

Extracellular matrix(ECM)-based biomaterials are promising candidates in cartilage tissue engineering by simulating the native microenvironment to regulate the chondrogenic differentiation of bone marrow mesenchymal stem cells(BMSCs)without exogenous growth *** biological properties of ECM scaffolds are primarily depended on the original source,which would directly influence the chondrogenic effects of the ECM *** the expanding investigations on ECM scaffolds in recent years,the selection of optimized ECM materials in cartilage regeneration was less *** this study,we harvested and compared the articular cartilage ECM from newborn,juvenile and adult *** results demonstrated the significant differences in the mechanical strength,sulphated glycosaminoglycan and collagen contents of the different aged ECM,before and after ***,different compositional and mechanical properties were shown in the three ECM-based collagen hydrogels,which exerted age-dependent chondrogenic *** general,both in vitro and in vivo results suggested that the newborn ECM promoted the most chondrogenesis of BMSCs but led to severe matrix *** contrast,BMSCs synthesized the lowest amount of cartilaginous matrix with minimal calcification with adult *** juvenile ECM achieved the best overall results in promoting chondrogenesis of BMSCs and preventing matrix ***,this study provides important information to our current knowledge in the design of future ECM-based biomaterials towards a successful repair of articular cartilage.

关键词： cartilage ECM mesenchymal stem cells collagen hydrogel chondrogenesis calcification