This paper, an addendum to “Dialectical Thermodynamics’ solution to the conceptual imbroglio that is the reversible path”, this journal, 10, 775-799, was written in response to the requests of several readers to pr...This paper, an addendum to “Dialectical Thermodynamics’ solution to the conceptual imbroglio that is the reversible path”, this journal, 10, 775-799, was written in response to the requests of several readers to provide further evidence of the said “imbroglio”. The evidence here presented relates to the incompatibility existing between the total-entropy and the Gibbs energy prescriptions for the reversible path. The previously published proof of the negentropic nature of the transformation of heat into work is here included to validate out conclusions about the Gibbs energy perspective.展开更多
Friendship paradox states that individuals are likely to have fewer friends than their friends do,on average.Despite of its wide existence and appealing applications in real social networks,the mathematical understand...Friendship paradox states that individuals are likely to have fewer friends than their friends do,on average.Despite of its wide existence and appealing applications in real social networks,the mathematical understanding of friendship paradox is very limited.Only few works provide theoretical evidence of single-step and multi-step friendship paradoxes,given that the neighbors of interest are onehop and multi-hop away from the target node.However,they consider non-evolving networks,as opposed to the topology of real social networks that are constantly growing over time.We are thus motivated to present a first look into friendship paradox in evolving networks,where newly added nodes preferentially attach themselves to those with higher degrees.Our analytical verification of both single-step and multistep friendship paradoxes in evolving networks,along with comparison to the non-evolving counterparts,discloses that“friendship paradox is even more paradoxical in evolving networks”,primarily from three aspects:1)we demonstrate a strengthened effect of single-step friendship paradox in evolving networks,with a larger probability(more than 0.8)of a random node’s neighbors having higher average degree than the random node itself;2)we unravel higher effectiveness of multi-step friendship paradox in seeking for influential nodes in evolving networks,as the rate of reaching the max degree node can be improved by a factor of at least Θ(t^(2/3))with t being the network size;3)we empirically verify our findings through both synthetic and real datasets,which suggest high agreements of results and consolidate the reasonability of evolving model for real social networks.展开更多
In this paper we summarize the characteristics of the dishpan experiment, the principle of substance revolving, and the scientific basis of the “retrograde wave in only one direction” with respect to weather data an...In this paper we summarize the characteristics of the dishpan experiment, the principle of substance revolving, and the scientific basis of the “retrograde wave in only one direction” with respect to weather data and S. C. OuYang＇s articles in which the fundamental questions in the meteorological theory were pointed out. Furthermore, we discuss the systematic changes involving the concept, theory, and method that substance evolves.展开更多
以英国中学地理教材Geography B Evolving Planet中的教材栏目为研究对象,结合其在教材中实际发挥的功能,将八种主要的教材栏目划分为问题思考类、技能训练类、信息提示类和考试导向类四大类。这四大类教材栏目体现出了不同的特点。问...以英国中学地理教材Geography B Evolving Planet中的教材栏目为研究对象,结合其在教材中实际发挥的功能,将八种主要的教材栏目划分为问题思考类、技能训练类、信息提示类和考试导向类四大类。这四大类教材栏目体现出了不同的特点。问题思考类栏目指向不同教学目标,技能训练类栏目凸显实用性和应用性的学科特色,信息提示类栏目关注学生心理特点,考试导向类栏目提高应试答题技巧。受此启发,未来我国中学地理教材栏目设置应有所侧重,即教材栏目在内容设置上要注重针对性,在形式设置上要增加多样性,在外观设置上要注重醒目性。展开更多
This paper tries to demarcate the evolving process of decategorization into three periods and exemplify it by studying the Chinese character Mao.The exemplification shows the correctness of the demarcation.
A multi-local-world model is introduced to describe the evolving networks that have a localization property such as the Internet. Based on this model, we show that the traffic load defined by 'betweenness centrali...A multi-local-world model is introduced to describe the evolving networks that have a localization property such as the Internet. Based on this model, we show that the traffic load defined by 'betweenness centrality' on the multi-local-world scale-free networks' model also follows a power law form. In this kind of network, a few vertices have heavier loads and so play more important roles than the others in the network.展开更多
In this paper we propose a simple evolving network with link additions as well as removals. The preferential attachment of link additions is similar to BA model’s, while the removal rule is newly added. From the pers...In this paper we propose a simple evolving network with link additions as well as removals. The preferential attachment of link additions is similar to BA model’s, while the removal rule is newly added. From the perspective of Markov chain, we give the exact solution of the degree distribution and show that whether the network is scale-free or not depends on the parameter m, and the degree exponent varying in （3, 5] is also depend on m if scale-free.展开更多
Association analysis is an effective data mining approach capable of unveiling interesting associations within a large dataset.Although widely adopted in e-business areas,it still has many difficulties when applied in...Association analysis is an effective data mining approach capable of unveiling interesting associations within a large dataset.Although widely adopted in e-business areas,it still has many difficulties when applied in practice.For instance,there is a mismatch between the static rules discovered and the drifting nature of the user interests,and it is difficult to detect associations from a huge volume of raw user data.This paper presents an effective approach to mine evolving association rules in order to tackle these problems.It is followed by a recommendation model based on the evolving association rules unveiled.Experimental results on an online toggery show that it can effectively unveil people's shifting interests and make better recommendations accordingly.展开更多
In some real complex networks, only a few nodes can obtain the global information about the entire networks, but most of the nodes own only local connections therefore own only local information of the networks. A new...In some real complex networks, only a few nodes can obtain the global information about the entire networks, but most of the nodes own only local connections therefore own only local information of the networks. A new local-world evolving network model is proposed in this paper. In the model, not all the nodes obtain local network information, which is different from the local world network model proposed by Li and Chen （LC model）. In the LC model, each node has only the local connections therefore owns only local information about the entire networks. Theoretical analysis and numerical simulation show that adjusting the ratio of the number of nodes obtaining the global information of the network to the total number of nodes can effectively control the valuing range for the power-law exponent of the new network. Therefore, if the topological structure of a complex network, especially its exponent of power-law degree distribution, needs controlling, we just add or take away a few nodes which own the global information of the network.展开更多
Complex hypernetworks are ubiquitous in the real system. It is very important to investigate the evolution mecha- nisms. In this paper, we present a local-world evolving hypernetwork model by taking into account the h...Complex hypernetworks are ubiquitous in the real system. It is very important to investigate the evolution mecha- nisms. In this paper, we present a local-world evolving hypernetwork model by taking into account the hyperedge growth and local-world hyperedge preferential attachment mechanisms. At each time step, a newly added hyperedge encircles a new coming node and a number of nodes from a randomly selected local world. The number of the selected nodes from the local world obeys the uniform distribution and its mean value is m. The analytical and simulation results show that the hyperdegree approximately obeys the power-law form and the exponent of hyperdegree distribution is 7 = 2 ＋ 1/m. Furthermore, we numerically investigate the node degree, hyperedge degree, clustering coefficient, as well as the average distance, and find that the hypemetwork model shares the scale-flee and small-world properties, which shed some light for deeply understanding the evolution mechanism of the real systems.展开更多
A virtual reconfigurable architecture(VRA)-based evolvable hardware is proposed for automatic synthesis of combinational logic circuits at gate-level.The proposed VRA is implemented by a Celoxica RC1000 peripheral com...A virtual reconfigurable architecture(VRA)-based evolvable hardware is proposed for automatic synthesis of combinational logic circuits at gate-level.The proposed VRA is implemented by a Celoxica RC1000 peripheral component interconnect(PCI)board with an Xilinx Virtex xcv2000E field programmable gate array(FPGA).To improve the quality of the evolved circuits,the VRA works through a two-stage evolution: finding a functional circuit and minimizing the number of logic gates used in a feasible circuit.To optimize the algorithm performance in the two-stage evolutionary process and set free the user from the time-consuming process of mutation parameter tuning,a self-adaptive mutation rate control(SAMRC)scheme is introduced.In the evolutionary process,the mutation rate control parameters are encoded as additional genes in the chromosome and also undergo evolutionary operations.The efficiency of the proposed methodology is tested with the evolutions of a 4-bit even parity function,a 2-bit multiplier,and a 3-bit multiplier.The obtained results demonstrate that our scheme improves the evolutionary design of combinational logic circuits in terms of quality of the evolved circuit as well as the computational effort,when compared to the existing evolvable hardware approaches.展开更多
In this paper, we propose an evolving network model growing fast in units of module, according to the analysis of the evolution characteristics in real complex networks. Each module is a small-world network containing...In this paper, we propose an evolving network model growing fast in units of module, according to the analysis of the evolution characteristics in real complex networks. Each module is a small-world network containing several interconnected nodes and the nodes between the modules are linked by preferential attachment on degree of nodes. We study the modularity measure of the proposed model, which can be adjusted by changing the ratio of the number of inner- module edges and the number of inter-module edges. In view of the mean-field theory, we develop an analytical function of the degree distribution, which is verified by a numerical example and indicates that the degree distribution shows characteristics of the small-world network and the scale-free network distinctly at different segments. The clustering coefficient and the average path length of the network are simulated numerically, indicating that the network shows the small-world property and is affected little by the randomness of the new module.展开更多
Thoracic Surgery is a continuous evolving specialty. In the past, thoracic surgeons had to make large incisions in order to operate any pathology inside the chest. This often meant big, painful and ugly scars and long...Thoracic Surgery is a continuous evolving specialty. In the past, thoracic surgeons had to make large incisions in order to operate any pathology inside the chest. This often meant big, painful and ugly scars and long recovery times after surgery. But he history of thoracic surgery changed since the begining of video-assisted thoracoscoDic surgery （VATg3展开更多
The squeezed back-to-back correlation(SBBC)of a boson-antiboson pair is sensitive to the time distribution of the particle-emitting source,and the SBBC function for an evolving source is expected to be affected by the...The squeezed back-to-back correlation(SBBC)of a boson-antiboson pair is sensitive to the time distribution of the particle-emitting source,and the SBBC function for an evolving source is expected to be affected by the relaxation time of the system.In this study,we investigated the effect of relaxation time on the SBBC function.We propose a method for calculating the SBBC function with relaxation-time approximation for evolving sources.SBBC functions of D^(0)D^(-0)in relativistic heavy-ion collisions were investigated using a hydrodynamic model.We found that the relaxation time reduces the amplitudes of the SBBC functions.This becomes apparent for long relaxation times and large initial relative deviations of the chaotic and squeezed amplitudes from their equilibrium values in the temporal steps.展开更多
Systematically sorting out the evolving pattern of solid waste management policies and studying the key points and development trends of solid waste management policies are conducive to the clarification of improvemen...Systematically sorting out the evolving pattern of solid waste management policies and studying the key points and development trends of solid waste management policies are conducive to the clarification of improvement path of solid waste management policies.Based on the promulgated solid waste management policies,this study applies statistical methods to the analysis of the text structure and contents of the solid waste management policies,attempting to find out the internal evolving pattern of the solid waste management policies in China.Closely integrating the current policy requirements for the construction of‘waste-free city’,this study puts forward a policy optimization and improvement path.The findings are briefly listed blow:①The solid waste management policies have demonstrated multiple text types and various levels of effectiveness,and the policy framework system is gradually optimized.②In each edition of solid waste management policy,the hotspot issues are highlighted with distinctive characteristics of the times and dynamic evolution.The policies are covering more fields,the contents are more targeted and comprehensive,and the implementation is more specific and practical.③The policies mainly focus on harmlessness,reduction,reclamation,pollution prevention,supervision and management,secondary pollution,recycling,circular economy,etc.④The government strengthens the top-level design from the macro level,focusing on policy guidance and standardization,policy coordination,technical support,and governance improvement to promote the realization of the goals of‘harmlessness,reduction,reclamation’.⑤The diversification of tools,approaches and factors supporting solid waste management,and the growing awareness of the technical support of solid waste management,and the management mode and governance path have entered the phase of adaptive transformation.Based on practical needs,the market oriented policies and incentive mechanisms for solid waste management are inadequate,applicable technical attention is not highly paid,and the comprehensive management level and governance capabilities are in urgent need of improvement.Combined with the theoretical research,practical actions and policy initiatives of the construction of‘waste-free city’in other countries,from the perspectives of solid waste full product lifecycle management,technical support paradigm policy,main body coordination policy,guidance incentive policy,laws and regulations and other aspects,the policy improvement path and direction of China’s‘waste-free city’are thoroughly discussed in this study.展开更多
Aimed at improving the insufficient search ability of constraint differential evolution with single constraint handling technique when solving complex optimization problem, this paper proposes a constraint differentia...Aimed at improving the insufficient search ability of constraint differential evolution with single constraint handling technique when solving complex optimization problem, this paper proposes a constraint differential evolution algorithm?based on ensemble of constraint handling techniques and multi-population?framework, called ECMPDE. First, handling three improved variants of differential evolution algorithms are dynamically matched with two constraint handling techniques through the constraint allocation mechanism. Each combination includes three variants with corresponding constraint handling technique?and these combinations are in the set. Second, the population is divided into three smaller subpopulations and one larger reward subpopulation. Then a combination with three constraint algorithms is randomly selected from the set, and the three constraint algorithms are run in three sub-populations respectively. According to the improvement of fitness value, the optimal constraint?algorithm is selected to run on the reward sub-population, which can share?information and close cooperation among populations. In order to verify the effectiveness of the proposed algorithm, 12 standard constraint optimization problems?and 10 engineering constraint optimization problems are tested. The experimental results show that ECMPDE is an effective algorithm for solving constraint optimization problems.展开更多
To accurately describe the evolving features of Mobile Ad Hoc Networks (MANETs) and to improve the performance of such networks, an evolving topology model with local-area preference is proposed. The aim of the model,...To accurately describe the evolving features of Mobile Ad Hoc Networks (MANETs) and to improve the performance of such networks, an evolving topology model with local-area preference is proposed. The aim of the model, which is analyzed by the mean field theory, is to optimize network structures based on users' behaviors in MANETs. The analysis results indicate that the network generated by this evolving model is a kind of scale-free network. This evolving model can improve the fault-tolerance performance of networks by balancing the connectivity and two factors, i.e., the remaining energy and the distance to nodes. The simulation results show that the evolving topology model has superior performance in reducing the traffic load and the energy consumption, prolonging network lifetime and improving the scalability of networks. It is an available approach for establishing and analyzing actual MANETs.展开更多
Web quality of service (QoS) awareness requires not only the selection of specific services to complete specific tasks, but also the comprehensive quality of service of the whole web service composition. How to select...Web quality of service (QoS) awareness requires not only the selection of specific services to complete specific tasks, but also the comprehensive quality of service of the whole web service composition. How to select the web service composition with the highest comprehensive QoS is a NP hard problem. In this paper, an improved multi population genetic algorithm is proposed. Cosine adaptive operator is added to the algorithm to avoid premature algorithm caused by improper genetic operator and the disadvantage of destroying excellent individuals in later period. Experimental results show that compared with the common genetic algorithm and multi population genetic algorithm, this algorithm has the advantages of shorter time consumption and higher accuracy, and effectively avoids the loss of effective genes in the population.展开更多
In order to explore the influence of different caving thicknesses on the MSS distributionand evolving characteristics of surrounding rocks in unsymmetrical disposal andfully mechanized top-coal caving (FMTC),based on ...In order to explore the influence of different caving thicknesses on the MSS distributionand evolving characteristics of surrounding rocks in unsymmetrical disposal andfully mechanized top-coal caving (FMTC),based on unsymmetrical disposal characteristics,the analyses of numerical simulation,material simulation and in-situ observation weresynthetically applied according to the geological and technical conditions of the 1151(3)working face in Xieqiao Mine.The results show that the stress peak value of the MSS-baseand the ratio of MSS-body height to caving thickness are nonlinear and inverselyproportional to the caving thickness.The MSS-base width,the MSS-body height,theMSS-base distance to working face wall and the rise distance of MSS-base beside coalpillar are nonlinear and directly proportional to the caving thickness.The characteristics ofMSS distribution and its evolving rules of surrounding rocks and the integrated cavingthickness effects are obtained.The investigations will provide lots of theoretic referencesto the surrounding rocks' stability control of the working face and roadway,roadway layout,gas extraction and exploitation,and efficiency of caving,etc.展开更多
As a Jewish woman writer from South Africa,Nadine Gordimer is a typical post-colonial novelist in the world history of literature.Her masterpiece Burger's Daughter has shown us her deep thinking about the relation...As a Jewish woman writer from South Africa,Nadine Gordimer is a typical post-colonial novelist in the world history of literature.Her masterpiece Burger's Daughter has shown us her deep thinking about the relation between the blacks and the whites in the revolution for the blacks' freedom.The thesis focuses on identity issue and analyzes how Rosa achieves self evolvement in different dialogues and her different life experiences.展开更多
文摘This paper, an addendum to “Dialectical Thermodynamics’ solution to the conceptual imbroglio that is the reversible path”, this journal, 10, 775-799, was written in response to the requests of several readers to provide further evidence of the said “imbroglio”. The evidence here presented relates to the incompatibility existing between the total-entropy and the Gibbs energy prescriptions for the reversible path. The previously published proof of the negentropic nature of the transformation of heat into work is here included to validate out conclusions about the Gibbs energy perspective.
基金supported by NSF China(No.61960206002,62020106005,42050105,62061146002)Shanghai Pilot Program for Basic Research–Shanghai Jiao Tong University.
文摘Friendship paradox states that individuals are likely to have fewer friends than their friends do,on average.Despite of its wide existence and appealing applications in real social networks,the mathematical understanding of friendship paradox is very limited.Only few works provide theoretical evidence of single-step and multi-step friendship paradoxes,given that the neighbors of interest are onehop and multi-hop away from the target node.However,they consider non-evolving networks,as opposed to the topology of real social networks that are constantly growing over time.We are thus motivated to present a first look into friendship paradox in evolving networks,where newly added nodes preferentially attach themselves to those with higher degrees.Our analytical verification of both single-step and multistep friendship paradoxes in evolving networks,along with comparison to the non-evolving counterparts,discloses that“friendship paradox is even more paradoxical in evolving networks”,primarily from three aspects:1)we demonstrate a strengthened effect of single-step friendship paradox in evolving networks,with a larger probability(more than 0.8)of a random node’s neighbors having higher average degree than the random node itself;2)we unravel higher effectiveness of multi-step friendship paradox in seeking for influential nodes in evolving networks,as the rate of reaching the max degree node can be improved by a factor of at least Θ(t^(2/3))with t being the network size;3)we empirically verify our findings through both synthetic and real datasets,which suggest high agreements of results and consolidate the reasonability of evolving model for real social networks.
文摘In this paper we summarize the characteristics of the dishpan experiment, the principle of substance revolving, and the scientific basis of the “retrograde wave in only one direction” with respect to weather data and S. C. OuYang＇s articles in which the fundamental questions in the meteorological theory were pointed out. Furthermore, we discuss the systematic changes involving the concept, theory, and method that substance evolves.
文摘以英国中学地理教材Geography B Evolving Planet中的教材栏目为研究对象,结合其在教材中实际发挥的功能,将八种主要的教材栏目划分为问题思考类、技能训练类、信息提示类和考试导向类四大类。这四大类教材栏目体现出了不同的特点。问题思考类栏目指向不同教学目标,技能训练类栏目凸显实用性和应用性的学科特色,信息提示类栏目关注学生心理特点,考试导向类栏目提高应试答题技巧。受此启发,未来我国中学地理教材栏目设置应有所侧重,即教材栏目在内容设置上要注重针对性,在形式设置上要增加多样性,在外观设置上要注重醒目性。
文摘This paper tries to demarcate the evolving process of decategorization into three periods and exemplify it by studying the Chinese character Mao.The exemplification shows the correctness of the demarcation.
基金This work was supported by the Hong Kong Research Grants Council under the CERG Grants CityU 1031/01E and 1115/03E.
文摘A multi-local-world model is introduced to describe the evolving networks that have a localization property such as the Internet. Based on this model, we show that the traffic load defined by 'betweenness centrality' on the multi-local-world scale-free networks' model also follows a power law form. In this kind of network, a few vertices have heavier loads and so play more important roles than the others in the network.
基金supported by the National Natural Science Foundation of China (10671212)Research Fund for the Doctoral Program of Higher Education of China (20050533036)
文摘In this paper we propose a simple evolving network with link additions as well as removals. The preferential attachment of link additions is similar to BA model’s, while the removal rule is newly added. From the perspective of Markov chain, we give the exact solution of the degree distribution and show that whether the network is scale-free or not depends on the parameter m, and the degree exponent varying in （3, 5] is also depend on m if scale-free.
基金the Key Project of the National Foundation of Science and Technology Research(No.2008ZX10005-013)State Key Laboratory Fund of Software Engineering in Wuhan University(No.SKLSE2010-08-31)the Science and Technology Planning Project of Guangdong Province,China(No.2010A032000002)
文摘Association analysis is an effective data mining approach capable of unveiling interesting associations within a large dataset.Although widely adopted in e-business areas,it still has many difficulties when applied in practice.For instance,there is a mismatch between the static rules discovered and the drifting nature of the user interests,and it is difficult to detect associations from a huge volume of raw user data.This paper presents an effective approach to mine evolving association rules in order to tackle these problems.It is followed by a recommendation model based on the evolving association rules unveiled.Experimental results on an online toggery show that it can effectively unveil people's shifting interests and make better recommendations accordingly.
基金supported by the Scientific Research Starting Foundation of Hangzhou Dianzi University (Grant No KYS091507073)partly by the National High Technology Research and Development Program of China (Grant No 2005AA147030)
文摘In some real complex networks, only a few nodes can obtain the global information about the entire networks, but most of the nodes own only local connections therefore own only local information of the networks. A new local-world evolving network model is proposed in this paper. In the model, not all the nodes obtain local network information, which is different from the local world network model proposed by Li and Chen （LC model）. In the LC model, each node has only the local connections therefore owns only local information about the entire networks. Theoretical analysis and numerical simulation show that adjusting the ratio of the number of nodes obtaining the global information of the network to the total number of nodes can effectively control the valuing range for the power-law exponent of the new network. Therefore, if the topological structure of a complex network, especially its exponent of power-law degree distribution, needs controlling, we just add or take away a few nodes which own the global information of the network.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.71071098,91024026,and 71171136)supported by the Shanghai Rising-Star Program,China(Grant No.11QA1404500)the Leading Academic Discipline Project of Shanghai City,China(Grant No.XTKX2012)
文摘Complex hypernetworks are ubiquitous in the real system. It is very important to investigate the evolution mecha- nisms. In this paper, we present a local-world evolving hypernetwork model by taking into account the hyperedge growth and local-world hyperedge preferential attachment mechanisms. At each time step, a newly added hyperedge encircles a new coming node and a number of nodes from a randomly selected local world. The number of the selected nodes from the local world obeys the uniform distribution and its mean value is m. The analytical and simulation results show that the hyperdegree approximately obeys the power-law form and the exponent of hyperdegree distribution is 7 = 2 ＋ 1/m. Furthermore, we numerically investigate the node degree, hyperedge degree, clustering coefficient, as well as the average distance, and find that the hypemetwork model shares the scale-flee and small-world properties, which shed some light for deeply understanding the evolution mechanism of the real systems.
基金Projects(61203308,61309014)supported by the National Natural Science Foundation of China
文摘A virtual reconfigurable architecture(VRA)-based evolvable hardware is proposed for automatic synthesis of combinational logic circuits at gate-level.The proposed VRA is implemented by a Celoxica RC1000 peripheral component interconnect(PCI)board with an Xilinx Virtex xcv2000E field programmable gate array(FPGA).To improve the quality of the evolved circuits,the VRA works through a two-stage evolution: finding a functional circuit and minimizing the number of logic gates used in a feasible circuit.To optimize the algorithm performance in the two-stage evolutionary process and set free the user from the time-consuming process of mutation parameter tuning,a self-adaptive mutation rate control(SAMRC)scheme is introduced.In the evolutionary process,the mutation rate control parameters are encoded as additional genes in the chromosome and also undergo evolutionary operations.The efficiency of the proposed methodology is tested with the evolutions of a 4-bit even parity function,a 2-bit multiplier,and a 3-bit multiplier.The obtained results demonstrate that our scheme improves the evolutionary design of combinational logic circuits in terms of quality of the evolved circuit as well as the computational effort,when compared to the existing evolvable hardware approaches.
基金supported by the National Natural Science Foundation of China (Grant No.51078165)the Fundamental Research Funds for Central Universities,China (Grant No.HUST 2010MS030)
文摘In this paper, we propose an evolving network model growing fast in units of module, according to the analysis of the evolution characteristics in real complex networks. Each module is a small-world network containing several interconnected nodes and the nodes between the modules are linked by preferential attachment on degree of nodes. We study the modularity measure of the proposed model, which can be adjusted by changing the ratio of the number of inner- module edges and the number of inter-module edges. In view of the mean-field theory, we develop an analytical function of the degree distribution, which is verified by a numerical example and indicates that the degree distribution shows characteristics of the small-world network and the scale-free network distinctly at different segments. The clustering coefficient and the average path length of the network are simulated numerically, indicating that the network shows the small-world property and is affected little by the randomness of the new module.
文摘Thoracic Surgery is a continuous evolving specialty. In the past, thoracic surgeons had to make large incisions in order to operate any pathology inside the chest. This often meant big, painful and ugly scars and long recovery times after surgery. But he history of thoracic surgery changed since the begining of video-assisted thoracoscoDic surgery （VATg3
基金supported by the National Natural Science Foundation of China (Nos. 12175031 and 11675034)
文摘The squeezed back-to-back correlation(SBBC)of a boson-antiboson pair is sensitive to the time distribution of the particle-emitting source,and the SBBC function for an evolving source is expected to be affected by the relaxation time of the system.In this study,we investigated the effect of relaxation time on the SBBC function.We propose a method for calculating the SBBC function with relaxation-time approximation for evolving sources.SBBC functions of D^(0)D^(-0)in relativistic heavy-ion collisions were investigated using a hydrodynamic model.We found that the relaxation time reduces the amplitudes of the SBBC functions.This becomes apparent for long relaxation times and large initial relative deviations of the chaotic and squeezed amplitudes from their equilibrium values in the temporal steps.
文摘Systematically sorting out the evolving pattern of solid waste management policies and studying the key points and development trends of solid waste management policies are conducive to the clarification of improvement path of solid waste management policies.Based on the promulgated solid waste management policies,this study applies statistical methods to the analysis of the text structure and contents of the solid waste management policies,attempting to find out the internal evolving pattern of the solid waste management policies in China.Closely integrating the current policy requirements for the construction of‘waste-free city’,this study puts forward a policy optimization and improvement path.The findings are briefly listed blow:①The solid waste management policies have demonstrated multiple text types and various levels of effectiveness,and the policy framework system is gradually optimized.②In each edition of solid waste management policy,the hotspot issues are highlighted with distinctive characteristics of the times and dynamic evolution.The policies are covering more fields,the contents are more targeted and comprehensive,and the implementation is more specific and practical.③The policies mainly focus on harmlessness,reduction,reclamation,pollution prevention,supervision and management,secondary pollution,recycling,circular economy,etc.④The government strengthens the top-level design from the macro level,focusing on policy guidance and standardization,policy coordination,technical support,and governance improvement to promote the realization of the goals of‘harmlessness,reduction,reclamation’.⑤The diversification of tools,approaches and factors supporting solid waste management,and the growing awareness of the technical support of solid waste management,and the management mode and governance path have entered the phase of adaptive transformation.Based on practical needs,the market oriented policies and incentive mechanisms for solid waste management are inadequate,applicable technical attention is not highly paid,and the comprehensive management level and governance capabilities are in urgent need of improvement.Combined with the theoretical research,practical actions and policy initiatives of the construction of‘waste-free city’in other countries,from the perspectives of solid waste full product lifecycle management,technical support paradigm policy,main body coordination policy,guidance incentive policy,laws and regulations and other aspects,the policy improvement path and direction of China’s‘waste-free city’are thoroughly discussed in this study.
文摘Aimed at improving the insufficient search ability of constraint differential evolution with single constraint handling technique when solving complex optimization problem, this paper proposes a constraint differential evolution algorithm?based on ensemble of constraint handling techniques and multi-population?framework, called ECMPDE. First, handling three improved variants of differential evolution algorithms are dynamically matched with two constraint handling techniques through the constraint allocation mechanism. Each combination includes three variants with corresponding constraint handling technique?and these combinations are in the set. Second, the population is divided into three smaller subpopulations and one larger reward subpopulation. Then a combination with three constraint algorithms is randomly selected from the set, and the three constraint algorithms are run in three sub-populations respectively. According to the improvement of fitness value, the optimal constraint?algorithm is selected to run on the reward sub-population, which can share?information and close cooperation among populations. In order to verify the effectiveness of the proposed algorithm, 12 standard constraint optimization problems?and 10 engineering constraint optimization problems are tested. The experimental results show that ECMPDE is an effective algorithm for solving constraint optimization problems.
基金supported by National Science and Technology Major Project under Grant No. 2012ZX03004001the National Natural Science Foundation of China under Grant No. 60971083
文摘To accurately describe the evolving features of Mobile Ad Hoc Networks (MANETs) and to improve the performance of such networks, an evolving topology model with local-area preference is proposed. The aim of the model, which is analyzed by the mean field theory, is to optimize network structures based on users' behaviors in MANETs. The analysis results indicate that the network generated by this evolving model is a kind of scale-free network. This evolving model can improve the fault-tolerance performance of networks by balancing the connectivity and two factors, i.e., the remaining energy and the distance to nodes. The simulation results show that the evolving topology model has superior performance in reducing the traffic load and the energy consumption, prolonging network lifetime and improving the scalability of networks. It is an available approach for establishing and analyzing actual MANETs.
文摘Web quality of service (QoS) awareness requires not only the selection of specific services to complete specific tasks, but also the comprehensive quality of service of the whole web service composition. How to select the web service composition with the highest comprehensive QoS is a NP hard problem. In this paper, an improved multi population genetic algorithm is proposed. Cosine adaptive operator is added to the algorithm to avoid premature algorithm caused by improper genetic operator and the disadvantage of destroying excellent individuals in later period. Experimental results show that compared with the common genetic algorithm and multi population genetic algorithm, this algorithm has the advantages of shorter time consumption and higher accuracy, and effectively avoids the loss of effective genes in the population.
基金Supported by National Basic Research Program(973)(2005cb221503)National Natural Science Foundation of China(50674003)Science and Technological Fund of Anhui Province for Outstanding Youth(08040106839)
文摘In order to explore the influence of different caving thicknesses on the MSS distributionand evolving characteristics of surrounding rocks in unsymmetrical disposal andfully mechanized top-coal caving (FMTC),based on unsymmetrical disposal characteristics,the analyses of numerical simulation,material simulation and in-situ observation weresynthetically applied according to the geological and technical conditions of the 1151(3)working face in Xieqiao Mine.The results show that the stress peak value of the MSS-baseand the ratio of MSS-body height to caving thickness are nonlinear and inverselyproportional to the caving thickness.The MSS-base width,the MSS-body height,theMSS-base distance to working face wall and the rise distance of MSS-base beside coalpillar are nonlinear and directly proportional to the caving thickness.The characteristics ofMSS distribution and its evolving rules of surrounding rocks and the integrated cavingthickness effects are obtained.The investigations will provide lots of theoretic referencesto the surrounding rocks' stability control of the working face and roadway,roadway layout,gas extraction and exploitation,and efficiency of caving,etc.
文摘As a Jewish woman writer from South Africa,Nadine Gordimer is a typical post-colonial novelist in the world history of literature.Her masterpiece Burger's Daughter has shown us her deep thinking about the relation between the blacks and the whites in the revolution for the blacks' freedom.The thesis focuses on identity issue and analyzes how Rosa achieves self evolvement in different dialogues and her different life experiences.
