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Dynamics of a Stochastic Epidemic Model with Age-group
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作者 LAN Xiaomin CHEN Guangmin +5 位作者 ZHOU Ruiyang ZHENG Kuicheng CAI Shaojian WEI Fengying JIN Zhen MAO Xuerong 《应用数学》 北大核心 2025年第1期294-307,共14页
A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,t... A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,the aging rates between two age groups are set to be constant.The existence-and-uniqueness of global positive solution is firstly showed.Then,by constructing several appropriate Lyapunov functions and using the high-dimensional Itô’s formula,the sufficient conditions for the stochastic extinction and stochastic persistence of the exposed individuals and the infected individuals are obtained.The stochastic extinction indicator and the stochastic persistence indicator are less-valued expressions compared with the basic reproduction number.Meanwhile,the main results of this study are modified into multi-age groups.Furthermore,by using the surveillance data for Fujian Provincial Center for Disease Control and Prevention,Fuzhou COVID-19 epidemic is chosen to carry out the numerical simulations,which show that the age group of the population plays the vital role when studying infectious diseases. 展开更多
关键词 Epidemic model Age groups PERSISTENCE EXTINCTION
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Effects of electroacupuncture at lower he-sea points on interleukin-1β and high mobility group box 1 in model rats with ulcerative colitis 被引量:4
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作者 张泓 易细芹 +2 位作者 凌希 吴金峰 艾坤 《World Journal of Acupuncture-Moxibustion》 CSCD 2015年第4期25-31,共7页
Objective To comparatively observe the effect of electroacupuncture at digestive system-related lower he-sea points on the expressions of serum interleukin-1β(IL-1 β), tumor necrosis factor-α(TNF-α) of colon t... Objective To comparatively observe the effect of electroacupuncture at digestive system-related lower he-sea points on the expressions of serum interleukin-1β(IL-1 β), tumor necrosis factor-α(TNF-α) of colon tissues and high mobility group box 1 protein(HMGB 1) of ulcerative colitis(UC) model rats, and to explore whether there is relative specificity of electroacupuncture at Shàngjùxū(上巨虚 ST 37), one of lower he-sea points of large intestine, in treatment of bowel diseases. Method A total of 60 SD rats were randomly divided into control group, model group, ST 37 group, Zúsānl?(足三里 ST 36) group, Xiàjùxū(下巨虚 ST 39) group and Yánglíngquán(阳陵泉 GB 34) group. There were ten rats in each group; five were males, and five were females. UC models were established by clysis with 2, 4, 6-trinitrobenzene sulfonic acid/alcohol solution. After modeling, treatment was conducted for ten days, specimens were collected, colonic ulcers and inflammation were inspected visually and scored. The content of serum IL-1β and the expressions of TNF-α and HMGB 1 in colon were detected through ELISA. Results 1 Compared with control group, the scores of colonic ulcers and inflammation, the content of serum IL-1β and the expressions of TNF-α(except ST 37 group) and HMGB 1 were all higher(P〈0.05, P〈0.01); 2 compared with model group, the scores of colonic ulcers in ST 36 group and ST 37 group were lower obviously(P〈0.05, P〈0.01); the expressions of IL-1β, TNF-α and HMGB 1 in the four treatment groups were lower obviously(P〈0.01); 3 compared with ST 37 group, the expressions of IL-1β, TNF-α and HMGB 1 in other three treatment groups were higher obviously(P〈0.05, P〈0.01); and the scores of colonic ulcers in ST 39 group and GB 34 group were higher obviously(P〈0.05). Conclusion 1 The score of colonic ulcers can be reduced through electroacupuncture at ST 37, ST 36, ST 39 and GB 34, which can also reduce the content of serum IL-1β and the expressions of TNF-α and HMGB 1, and effectively inhibit inflammatory response of colon caused by UC; 2 the effect trend of the four acupoints in treatment of UC is: ST 37ST 36ST 39GB 34, and electroacupuncture at ST 37 has the best effect with relative specificity. 展开更多
关键词 ELECTROACUPUNCTURE lower he-sea points ulcerative colitis(UC) model rats interleukin-1β(IL-1β) tumor necrosis factor-α high mobility group box 1 protein(HMGB 1) curing viscera diseases by he-sea points
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Sedimentary facies and depositional model of shallow water delta dominated by fluvial for Chang 8 oil-bearing group of Yanchang Formation in southwestern Ordos Basin,China 被引量:12
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作者 陈林 陆永潮 +5 位作者 吴吉元 邢凤存 刘璐 马义权 饶丹 彭丽 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第12期4749-4763,共15页
A systematic analysis of southwestern Ordos Basin's sedimentary characteristics,internal architectural element association styles and depositional model was illustrated through core statistics,well logging data an... A systematic analysis of southwestern Ordos Basin's sedimentary characteristics,internal architectural element association styles and depositional model was illustrated through core statistics,well logging data and outcrop observations in Chang 8 oil-bearing group.This analysis indicates that shallow water delta sediments dominated by a fluvial system is the primary sedimentary system of the Chang 8 oil-bearing group of the Yanchang Formation in southwestern Ordos Basin.Four microfacies with fine grain sizes are identified: distributary channels,sheet sandstone,mouth bar and interdistributary fines.According to the sandbody's spatial distribution and internal architecture,two types of sandbody architectural element associations are identified: amalgamated distributary channels and thin-layer lobate sandstone.In this sedimentary system,net-like distributary channels at the delta with a narrow ribbon shape compose the skeleton of the sandbody that extends further into the delta front and shades into contiguous lobate distribution sheet sandstone in the distal delta front.The mouth bar is largely absent in this system.By analyzing the palaeogeomorphology,the palaeostructure background,sedimentary characteristics,sedimentary facies types and spatial distribution of sedimentary facies during the Chang 8 period,a distinctive depositional model of the Chang 8 shallow water fluvial-dominated delta was established,which primarily consists of straight multi-phase amalgamated distributary channels in the delta plain,net-like distributary channels frequently diverting and converging in the proximal delta front,sheet sandstones with dispersing contiguous lobate shapes in the distal delta front,and prodelta or shallow lake mudstones. 展开更多
关键词 sedimentary facies architectural element DEPOSITIONAL model shallow water delta CHANG 8 oil-bearing group ORDOS Basin
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Modeling walking behavior of pedestrian groups with floor field cellular automaton approach 被引量:4
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作者 陆丽丽 任刚 +1 位作者 王炜 王义 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第8期654-660,共7页
Walking in groups is very common in a realistic walking environment. An extended floor field cellular automaton (CA) model is therefore proposed to describe the walking behavior of pedestrian groups, This model repr... Walking in groups is very common in a realistic walking environment. An extended floor field cellular automaton (CA) model is therefore proposed to describe the walking behavior of pedestrian groups, This model represents the motion of pedestrian groups in a realistic way. The simulation results reveal that the walking behavior of groups has an important but negative influence on pedestrian flow dynamics, especially when the density is at a high level. The presence of pedestrian groups retards the emergence of lane formation and increases the instability of operation of pedestrian flow. Moreover, the average velocity and volume of pedestrian flow are significantly reduced due to the group motion. Meanwhile, the parameter-sensitive analysis suggests that pedestrian groups should make a compromise between efficient movement and staying coherent with a certain spatial structure when walking in a dense crowd. 展开更多
关键词 pedestrian groups floor field CA model leader-follower pattern simulation
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Physical modeling of behaviors of cast-in-place concrete piled raft compared to free-standing pile group in sand 被引量:1
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作者 Mehdi Sharafkhah Issa Shooshpasha 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2018年第4期703-716,共14页
Similar to free-standing pile groups, piled raft foundations are conventionally designed in which the piles carry the total load of structure and the raft bearing capacity is not taken into account. Numerous studies i... Similar to free-standing pile groups, piled raft foundations are conventionally designed in which the piles carry the total load of structure and the raft bearing capacity is not taken into account. Numerous studies indicated that this method is too conservative. Only when the pile cap is elevated from the ground level,the raft bearing contribution can be neglected. In a piled raft foundation, pileesoileraft interaction is complicated. Although several numerical studies have been carried out to analyze the behaviors of piled raft foundations, very few experimental studies are reported in the literature. The available laboratory studies mainly focused on steel piles. The present study aims to compare the behaviors of piled raft foundations with free-standing pile groups in sand, using laboratory physical models. Cast-in-place concrete piles and concrete raft are used for the tests. The tests are conducted on single pile, single pile in pile group, unpiled raft, free-standing pile group and piled raft foundation. We examine the effects of the number of piles, the pile installation method and the interaction between different components of foundation. The results indicate that the ultimate bearing capacity of the piled raft foundation is considerably higher than that of the free-standing pile group with the same number of piles. With installation of the single pile in the group, the pile bearing capacity and stiffness increase. Installation of the piles beneath the raft decreases the bearing capacity of the raft. When the raft bearing capacity is not included in the design process, the allowable bearing capacity of the piled raft is underestimated by more than 200%. This deviation intensifies with increasing spacing of the piles. 展开更多
关键词 Free-standing pile group Piled raft Pileesoileraft interaction Physical modeling Cast-in-place concrete piles
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Consensus model of social network group decision-making based on trust relationship among experts and expert reliability 被引量:4
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作者 WANG Ya CAI Mei JIAN Xinglian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第6期1576-1588,共13页
Due to people’s increasing dependence on social networks,it is essential to develop a consensus model considering not only their own factors but also the interaction between people.Both external trust relationship am... Due to people’s increasing dependence on social networks,it is essential to develop a consensus model considering not only their own factors but also the interaction between people.Both external trust relationship among experts and the internal reliability of experts are important factors in decision-making.This paper focuses on improving the scientificity and effectiveness of decision-making and presents a consensus model combining trust relationship among experts and expert reliability in social network group decision-making(SN-GDM).A concept named matching degree is proposed to measure expert reliability.Meanwhile,linguistic information is applied to manage the imprecise and vague information.Matching degree is expressed by a 2-tuple linguistic model,and experts’preferences are measured by a probabilistic linguistic term set(PLTS).Subsequently,a hybrid weight is explored to weigh experts’importance in a group.Then a consensus measure is introduced and a feedback mechanism is developed to produce some personalized recommendations with higher group consensus.Finally,a comparative example is provided to prove the scientificity and effectiveness of the proposed consensus model. 展开更多
关键词 social network group decision-making(SN-GDM) trust relationship expert reliability consensus model probabilistic linguistic term set(PLTS).
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GLOBAL STABILITY OF EXTENDED MULTI-GROUP SIR EPIDEMIC MODELS WITH PATCHES THROUGH MIGRATION AND CROSS PATCH INFECTION 被引量:8
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作者 Yoshiaki MUROYA Yoichi ENATSU Toshikazu KUNIYA 《Acta Mathematica Scientia》 SCIE CSCD 2013年第2期341-361,共21页
In this article, we establish the global stability of an endemic equilibrium of multi-group SIR epidemic models, which have not only an exchange of individuals between patches through migration but also cross patch in... In this article, we establish the global stability of an endemic equilibrium of multi-group SIR epidemic models, which have not only an exchange of individuals between patches through migration but also cross patch infection between different groups. As a result, we partially generalize the recent result in the article [16]. 展开更多
关键词 multi-group SIR epidemic model PATCH global asymptotic stability Lyapunovfunction
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Group Decision-Making Model of Renal Cancer Surgery Options Using Entropy Fuzzy Element Aczel-Alsina Weighted Aggregation Operators under the Environment of Fuzzy Multi-Sets 被引量:1
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作者 Jing Fu Jun Ye Liping Xie 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第3期1751-1769,共19页
Since existing selection methods of surgical treatment schemes of renal cancer patients mainly depend on physicians’clinical experience and judgments,the surgical treatment options of renal cancer patients lack their... Since existing selection methods of surgical treatment schemes of renal cancer patients mainly depend on physicians’clinical experience and judgments,the surgical treatment options of renal cancer patients lack their scientifical and reasonable information expression and group decision-making model for renal cancer patients.Fuzzy multi-sets(FMSs)have a number of properties,which make them suitable for expressing the uncertain information of medical diagnoses and treatments in group decision-making(GDM)problems.To choose the most appropriate surgical treatment scheme for a patient with localized renal cell carcinoma(RCC)(T1 stage kidney tumor),this article needs to develop an effective GDM model based on the fuzzy multivalued evaluation information of the renal cancer patients.First,we propose a conversionmethod of transforming FMSs into entropy fuzzy sets(EFSs)based on the mean and Shannon entropy of a fuzzy sequence in FMS to reasonably simplify the information expression and operations of FMSs and define the score function of an entropy fuzzy element(EFE)for ranking EFEs.Second,we present the Aczel-Alsina t-norm and t-conorm operations of EFEs and the EFE Aczel-Alsina weighted arithmetic averaging(EFEAAWAA)and EFE Aczel-Alsina weighted geometric averaging(EFEAAWGA)operators.Third,we develop a multicriteria GDM model of renal cancer surgery options in the setting of FMSs.Finally,the proposed GDM model is applied to two clinical cases of renal cancer patients to choose the best surgical treatment scheme for a renal cancer patient in the setting of FMSs.The selected results of two clinical cases verify the efficiency and rationality of the proposed GDM model in the setting of FMSs. 展开更多
关键词 Fuzzy multi-set entropy fuzzy element entropy fuzzy element Aczel-Alsina weighted arithmetic averaging operator entropy fuzzy element Aczel-Alsina weighted geometric averaging operator renal cancer surgical treatment option group decision-making model
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A modified multi-group model of angular and momentum distribution of cosmic ray muons for thickness measurement and material discrimination of slabs 被引量:5
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作者 Sa Xiao Wei-Bo He +2 位作者 Ming-Cong Lan Ying Chen Mao-Bing Shuai 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第2期111-117,共7页
Muon tomography is a capable imaging technique to measure the geometry of high-Z objects. However,most existed algorithms used in muon tomography have obscured the effects of angular distribution and momentum spectra ... Muon tomography is a capable imaging technique to measure the geometry of high-Z objects. However,most existed algorithms used in muon tomography have obscured the effects of angular distribution and momentum spectra of cosmic ray muons and reduced the spatial resolution. We present a modified multi-group model that takes into account these effects and calibrates the model by the material of lead. Performance tests establish that the model is capable of measuring the thickness of a Pb slab and identifying the material of an unknown slab on a reasonable exposure timescale, in both cases of complete and incomplete angular data. Results show that the modified multi-group model is helpful for improvements in image resolution in real applications. 展开更多
关键词 MUON tomography MODIFIED MULTI-group model ANGULAR distribution MOMENTUM spectra
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Group A streptococcal antigen exposed rat model to investigate neurobehavioral and cardiac complications associated with post-streptococcal autoimmune sequelae 被引量:1
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作者 Rukshan A.M.Rafeek Catherine M.Lobbe +5 位作者 Ethan C.Wilkinson Adam S.Hamlin Nicholas M.Andronicos David J.McMillan Kadaba S.Sriprakash Natkunam Ketheesan 《Animal Models and Experimental Medicine》 CSCD 2021年第2期151-161,共11页
Background:The neuropsychiatric disorders due to post-streptococcal autoimmune complications such as Sydenham's chorea(SC)are associated with acute rheumatic fever and rheumatic heart disease(ARF/RHD).An animal mo... Background:The neuropsychiatric disorders due to post-streptococcal autoimmune complications such as Sydenham's chorea(SC)are associated with acute rheumatic fever and rheumatic heart disease(ARF/RHD).An animal model that exhibits char-acteristics of both cardiac and neurobehavioral defects in ARF/RHD would be an important adjunct for future studies.Since age,gender,strain differences,and geno-types impact on the development of autoimmunity,we investigated the behavior of male and female Wistar and Lewis rat strains in two age cohorts(6 weeks and 12 weeks)under normal husbandry conditions and following exposure to group A streptococcus(GAS).Methods:Standard behavioral assessments were performed to determine the impair-ments in fine motor control(food manipulation test),gait and balance(beam walk-ing test),and obsessive-compulsive behavior(grooming and marble burying tests).Furthermore,electrocardiography,histology,and behavioral assessments were per-formed on male and female Lewis rats injected with GAS antigens.Results:For control Lewis rats there were no significant age and gender dependent differences in marble burying,food manipulation,beam walking and grooming be-haviors.In contrast significant age-dependent differences were observed in Wistar rats in all the behavioral tests except for food manipulation.Therefore,Lewis rats were selected for further experiments to determine the effect of GAS.After ex-posure to GAS,Lewis rats demonstrated neurobehavioral abnormalities and cardiac pathology akin to SC and ARF/RHD,respectively.Conclusion:We have characterised a new model that provides longitudinal stability of age-dependent behavior,to simultaneously investigate both neurobehavioral and cardiac abnormalities associated with post-streptococcal complications. 展开更多
关键词 animal model group A streptococcus Lewis rats paediatric autoimmune neuropsychiatric disorders associated with streptococcal infections(PANDAS) rheumatic fever rheumatic heart disease sydenham chorea(SC)
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Global dynamics of a novel multi-group model for computer worms 被引量:3
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作者 巩永旺 宋玉蓉 蒋国平 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期56-62,共7页
In this paper, we study worm dynamics in computer networks composed of many autonomous systems. A novel multigroup SIQR (susceptible-infected-quarantined-removed) model is proposed for computer worms by explicitly c... In this paper, we study worm dynamics in computer networks composed of many autonomous systems. A novel multigroup SIQR (susceptible-infected-quarantined-removed) model is proposed for computer worms by explicitly considering anti-virus measures and the network infrastructure. Then, the basic reproduction number of worm R0 is derived and the global dynamics of the model are established. It is shown that if R0 is less than or equal to 1, the disease-free equilibrium is globally asymptotically stable and the worm dies out eventually, whereas, if R0 is greater than 1, one unique endemic equilibrium exists and it is globally asymptotically stable, thus the worm persists in the network. Finally, numerical simulations are given to illustrate the theoretical results. 展开更多
关键词 computer worm multi-group model Lyapunov function global dynamics
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Derivation of a second-order model for Reynolds stress using renormalization group analysis and the two-scale expansion technique
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作者 Xiao-Hong Wang Zheng-Feng Liu Xiao-Xia Lu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第5期649-659,共11页
With the two-scale expansion technique proposed by Yoshizawa,the turbulent fluctuating field is expanded around the isotropic field.At a low-order two-scale expansion,applying the mode coupling approximation in the Ya... With the two-scale expansion technique proposed by Yoshizawa,the turbulent fluctuating field is expanded around the isotropic field.At a low-order two-scale expansion,applying the mode coupling approximation in the Yakhot-Orszag renormalization group method to analyze the fluctuating field,the Reynolds-average terms in the Reynolds stress transport equation,such as the convective term,the pressure-gradient-velocity correlation term and the dissipation term,are modeled.Two numerical examples:turbulent flow past a backward-facing step and the fully developed flow in a rotating channel,are presented for testing the efficiency of the proposed second-order model.For these two numerical examples,the proposed model performs as well as the Gibson-Launder (GL) model,giving better prediction than the standard k-ε model,especially in the abilities to calculate the secondary flow in the backward-facing step flow and to capture the asymmetric turbulent structure caused by frame rotation. 展开更多
关键词 Turbulent modeling Renormalization group Two-scale expansion Reynolds stress transport equation Second-order model
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Exact solutions to drift-flux multiphase flow models through Lie group symmetry analysis
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作者 B.BIRA T.R.SEKHAR 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第8期1105-1112,共8页
In the present paper, Lie group symmetry method is used to obtain some exact solutions for a hyperbolic system of partial differential equations (PDEs), which governs an isothermal no-slip drift-flux model for multi... In the present paper, Lie group symmetry method is used to obtain some exact solutions for a hyperbolic system of partial differential equations (PDEs), which governs an isothermal no-slip drift-flux model for multiphase flow problem. Those sym- metries are used for the governing system of equations to obtain infinitesimal transforma- tions, which consequently reduces the governing system of PDEs to a system of ODEs. Further, the solutions of the system of ODEs which in turn produces some exact solutions for the PDEs are presented. Finally, the evolutionary behavior of weak discontinuity is discussed. 展开更多
关键词 multiphase flow drift-flux models Lie group analysis exact solution weakdiscontinuity
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Dynamic modeling of spacecraft solar panels deployment with Lie group variational integrator
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作者 Long Bai Xinsheng Ge 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2018年第6期415-424,I0005,共11页
The spacecraft with multistage solar panels have nonlinear coupling between attitudes of central body and solar panels, especially the rotation of central body is considered in space. The dynamics model is based for d... The spacecraft with multistage solar panels have nonlinear coupling between attitudes of central body and solar panels, especially the rotation of central body is considered in space. The dynamics model is based for dynamics analysis and control, and the multistage solar panels means the dynamics modeling will be very complex. In this research, the Lie group variational integrator method is introduced, and the dynamics model of spacecraft with solar panels that connects together by flexible joints is built. The most obvious character of this method is that the attitudes of central body and solar panels are all described by three-dimensional attitude matrix. The dynamics models of spacecraft with one and three solar panels are established and simulated. The study shows Lie group variational integrator method avoids parameters coupling and effectively reduces difficulty of modeling. The obtained continuous dynamics model based on Lie group is a set of ordinary differential equations and equivalent with traditional dynamics model that offers a basis for the geometry control. 展开更多
关键词 Lie group Variational integrator SPACECRAFT Solar panels deployment Dynamics modeling
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Research on the Protection of Vulnerable Groups in Water Pollution Conflicts Based on Binomial Tree Pricing Model
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作者 Yanping Chen Tiejun Cheng Fengping Wu 《Journal of Water Resource and Protection》 2015年第8期659-664,共6页
The interests of vulnerable groups can’t be guaranteed due to their weaker capacity and the limited interests demand channels during the water pollution conflicts. The interest protection for the vulnerable people in... The interests of vulnerable groups can’t be guaranteed due to their weaker capacity and the limited interests demand channels during the water pollution conflicts. The interest protection for the vulnerable people in the water pollution conflicts has attracted attentions of the international scholars. The paper tries to construct the market mechanism which can make the vulnerable people to involve in the emission trading. The vulnerable people can buy American put option in the emission trading market. When the price of the emission runs below the contract price, the vulnerable people can get the benefit through executing the option. When the price of the emission runs above the contract price, the vulnerable people can give up the right. The binomial tree option pricing model can help the vulnerable people to make a decision through the analysis of the worth of the American put option. 展开更多
关键词 VULNERABLE groups Water Pollution Conflicts Emission TRADING American PUT OPTION BINOMIAL Tree OPTION PRICING model
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Hierarchical Merging &Generalization Method of Three-Dimension City Model Group Based on the Theory of Spatial Visual Cognition
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作者 Chaokui Li Jianhui Chen +2 位作者 Jun Fang Huiting Li Pu Bu 《Journal of Geographic Information System》 2019年第2期124-137,共14页
In order to simplify the three-dimensional building group model, this paper proposes a clustering generalization method based on visual cognitive theory. The method uses road elements to roughly divide scenes, and the... In order to simplify the three-dimensional building group model, this paper proposes a clustering generalization method based on visual cognitive theory. The method uses road elements to roughly divide scenes, and then uses spatial cognitive elements such as direction, area, height and their topological constraints to classify them precisely, so as to make them conform to the urban morphological characteristics. Delaunay triangulation network and boundary tracking synthesis algorithm are used to merge and summarize the models, and the models are stored hierarchically. The proposed algorithm should be verified experimentally with a typical urban complex model. The experimental results show that the efficiency of the method used in this paper is at least 20% higher than that of previous one, and with the growth of test data, the higher efficiency is improved. The classification results conform to human cognitive habits, and the generalization levels of different models can be relatively unified by adaptive control of each threshold in the clustering generalization process. 展开更多
关键词 Visual COGNITION 3D Building model group Geometry THRESHOLD Hierarchical GENERALIZATION Cluster GENERALIZATION
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Concave Group Selection of Nonparameter Additive Accelerated Failure Time Model
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作者 Ling Zhu 《Open Journal of Statistics》 2021年第1期137-161,共25页
In this paper, we have studied the nonparameter accelerated failure time (AFT) additive regression model, whose covariates have a nonparametric effect on high-dimensional censored data. We give the asymptotic property... In this paper, we have studied the nonparameter accelerated failure time (AFT) additive regression model, whose covariates have a nonparametric effect on high-dimensional censored data. We give the asymptotic property of the penalty estimator based on GMCP in the nonparameter AFT model. 展开更多
关键词 Accelerated Failure Time model Nonparameter model group Minimax Concave Penalty Weighted Least Squares Estimation
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Performance Evaluation of Routing Protocols on the Reference Region Group Mobility Model for MANET
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作者 Yan Zhang Chor Ping Low Jim Mee Ng 《Wireless Sensor Network》 2011年第3期92-105,共14页
Group mobility is prevalent in many mobile ad hoc network (MANET) applications, such as disaster recovery, military operations, searching and rescue activities. Group partition, as an inherent phenomenon in group mobi... Group mobility is prevalent in many mobile ad hoc network (MANET) applications, such as disaster recovery, military operations, searching and rescue activities. Group partition, as an inherent phenomenon in group mobility, may occur when mobile nodes move in diverse mobility patterns and it causes the network to be partitioned into disconnected components. It may result in severe link disconnections, which interrupts network communications. To address this concern, we proposed a novel group mobility model in this paper, namely the Reference Region Group Mobility model, which can be used to mimic group operations in MANETs, i.e. group partitions and mergers. Based on this model, a comprehensive study on the impact of group partitions to the performance of network routing protocols are carried out by evaluating two well-known routing protocols, namely the Ad Hoc On-demand Distance Vector Routing protocol (AODV) and the Dynamic Source Routing protocol (DSR). The simulation results reflect that group partitions have a significant impact to the performance of network routing protocols. 展开更多
关键词 Ad HOC Network group Mobility model group PARTITION Routing AODV DSR
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SU(3) Simple Group Model and New Z' Properties in Future Linear Colliders
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作者 LIU Yao-Bei WANG Shuai-Wei ZHANG Wen-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第2期299-304,共6页
In the SU(3) simple group model, the new neutral gauge boson Z' couples to pairs of SM fermions with couplings fixed in terms of the SM gauge couplings and depending only on the choice of the fermion embedding. In ... In the SU(3) simple group model, the new neutral gauge boson Z' couples to pairs of SM fermions with couplings fixed in terms of the SM gauge couplings and depending only on the choice of the fermion embedding. In this paper, we calculate the contributions of this new particle to the processes e^+e^-→l^+l^-, bb^-, and cc^- and study the possibility of detecting this new particle via these processes in the future high-energy linear e^+e^- collider(LC) experiments with √s= 500 GeV and £int= 340 fb^-1. We find that the new gauge boson Z' is most sensitive to the process e^+e^-→b^+b^-. As long as Mz,≤2 TeV , the absolute values of the relative correction parameter are larger than 5%. We calculate the forward-backward asymmetries and left-right asymmetries for the process e^+e^-→c^+c^-, with both the universal and anomaly-free fermion embeddings. Bounds on Z' masses are also estimated within 95% confidence level. 展开更多
关键词 SU(3) simple group model relative corrections forward-backward asymmetry left-right asymme-try new gauge boson
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The Game Model Analysis between the Individual and the Group
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作者 Dehai Liu Dagang Wang Shulin Liu 《Chinese Business Review》 2004年第2期29-32,共4页
This paper analyses the game model between the individual and the group that has the characteristics of Stackelberg model in traditional game theory and replicator dynamic model in evolutionary game theory.In the firs... This paper analyses the game model between the individual and the group that has the characteristics of Stackelberg model in traditional game theory and replicator dynamic model in evolutionary game theory.In the first phase of game,the bounded rationality group players adopt the replicator dynamic behavior.Secondly,the full rationality individual player decides the own response function by the strategies distribution of group players.The shortsighted individual player will take the risk-dominant strategy.This model has some unique characteristics. 展开更多
关键词 the individual and the group Stackelberg model replicator dynamic group decision-making
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