Social media have dramatically changed the mode of information dissemination.Various models and algorithms have been developed to model information diffusion and address the influence maximization problem in complex s...Social media have dramatically changed the mode of information dissemination.Various models and algorithms have been developed to model information diffusion and address the influence maximization problem in complex social networks.However,it appears difficult for state-of-the-art models to interpret complex and reversible real interactive networks.In this paper,we propose a novel influence diffusion model,i.e.,the Operator-Based Model(OBM),by leveraging the advantages offered from the heat diffusion based model and the agent-based model.The OBM improves the performance of simulated dissemination by considering the complex user context in the operator of the heat diffusion based model.The experiment obtains a high similarity of the OBM simulated trend to the real-world diffusion process by use of the dynamic time warping method.Furthermore,a novel influence maximization algorithm,i.e.,the Global Topical Support Greedy algorithm(GTS-Greedy algorithm),is proposed corresponding to the OBM.The experimental results demonstrate its promising performance by comparing it against other classic algorithms.展开更多
The modified shear lag model proposed recently was applied to calculate thermal residual stresses and subsequent stress distributions under tensile and compressive loadings. The expressions for the elastic moduli and ...The modified shear lag model proposed recently was applied to calculate thermal residual stresses and subsequent stress distributions under tensile and compressive loadings. The expressions for the elastic moduli and the yield strengths under tensile and compressive loadings were derived which take account of thermal residual stresses. The asymmetries in the elastic modulus and the yield strength were interpreted using the derived expressions and the obtained results of the stress calculations. The model predictions have exhibited good agreements with the experimental results and also with the other theoretical predictions展开更多
Based on risk social cognition theory and planned behavior theory, the influence factors of the public participation in the nanotechnology risk communication are analyzed,and the concept model is presented to analyze ...Based on risk social cognition theory and planned behavior theory, the influence factors of the public participation in the nanotechnology risk communication are analyzed,and the concept model is presented to analyze their relationships and functional mechanism. In the model,the risk communication behaviors are divided into two variables of the public opinion expression and information acquisition,and the subjective norm divided into the internal and external social networks. Then the questionnaire is designed so as to verify the proposed model and analyze their relationships. The survey data are analyzed using SMART PLS software. The validity analysis shows that the questionnaire has a high convergence and discriminant validity. In addition, the Cronbach'a coefficient of each item is more than 0. 70,which shows the questionnaire has a high credibility. Based on the statistical data analysis, relationships of the influence factors are obtained.Further,the influence path model of the public attitude,intention,self regulation and behavior control in the risk communication is established. According to the Bootstrap algorithm in SMART,the path coefficient and its explanation variance of each influence factor are obtained. The calculation results show that the explanation variance values are all bigger than 10% and the path is reliable.Based on the path model, the influence path and function relationships of the participation attitude, subjective norm and behavior control on the participation intention and behavior are obtained. This will provide theoretical and data supports for the risk management and strategy making of the public participation in nanotechnology risk communication.展开更多
Amyloid peptide(Aβ)oligomers are considered one of the primary causal factors for the synaptic loss characteristic of Alzheimer’s disease(AD)(Karran and De Strooper,2016).However,Aβis generated in normal brai...Amyloid peptide(Aβ)oligomers are considered one of the primary causal factors for the synaptic loss characteristic of Alzheimer’s disease(AD)(Karran and De Strooper,2016).However,Aβis generated in normal brains and accumulates at synaptic sites,which raises the question whether Aβplays a physiological role in synapses.展开更多
Diffusion has been systematically described as the main mechanism of chloride transport in reinforced concrete(RC) structure, especially when the concrete is in a saturated state. However, the single mechanism of di...Diffusion has been systematically described as the main mechanism of chloride transport in reinforced concrete(RC) structure, especially when the concrete is in a saturated state. However, the single mechanism of diffusion is not able to describe the actual chloride ingress in the nonsaturated concrete. Instead, it is dominated by the interaction of diffusion and convection. With the synergetic effects of various factors taken into account, this study aimed to modify and develop an analytical convection- diffusion coupling model for chloride transport in nonsaturated concrete. The model was verified by simulation of laboratory tests and field measurement. The results of comparison study demonstrate that the analytical model developed in this study is efficient and accurate in predicting the chloride profiles in the nonsaturated concrete.展开更多
During the experiment of gas/liquid coaxial swirl injector conducted with air and water under atmosphere environment, it is observed that the injector may selfoscillate. The self oscillation periodically occurs and va...During the experiment of gas/liquid coaxial swirl injector conducted with air and water under atmosphere environment, it is observed that the injector may selfoscillate. The self oscillation periodically occurs and vanishes with the increasing velocity of the gas flow.A theoretical model is presented based on the experiment investigation. Simulation of the acoustic process has been performed and conclusions consistent with the experiment can be drawn from the theoretical model, which explains the exPeriment phenomena quite well. At last, the comparison between phenomena of the self oscillation and some experiments of LRE indicates that some instability phenomena in oxygen/hydrogen propellant rocket engine may be the related to self oscillation in coaxial injectors展开更多
Streamwise Body Force Model(SBFM)could be used to simulate the force of blade on the airflow,resulting in rapid propulsion-airframe integrated simulation.However,when subjected to inlet distortion,the upstream flow fi...Streamwise Body Force Model(SBFM)could be used to simulate the force of blade on the airflow,resulting in rapid propulsion-airframe integrated simulation.However,when subjected to inlet distortion,the upstream flow field of fan stage is redistributed,which causes inaccurate prediction of fan stage performance.As inspired by the upstream influence of compressor,this paper aims to present a modification strategy for SBFM method to predict the compressor performance under circumferential inlet distortion without any knowledge of compressor geometry.Based on the linearized motion equation,the Upstream Influence Model(UIM)is introduced to predict the upstream flow field redistribution.Then the theoretical Mach number at Aerodynamic Interface Plane(AIP)position is calculated and selected to determine the corresponding body force coefficients based on the functional relationship between body force coefficients and Mach number,thus the upstream influence of compressor could be accurately quantified and the Modified Streamwise Body Force Model(MSBFM)could be established.Two studied cases are calculated with different methods and the upstream flow fields are analyzed.The prediction error of MSBFM method for compressor adiabatic efficiency is less than 3%,and the calculation efficiency is improved 20 times under the condition of ensuring computing accuracy.The MSBFM method has the potential for rapid propulsion-airframe integrated simulation.展开更多
With the rapid development of location-based networks, point-of-interest(POI) recommendation has become an important means to help people discover interesting and attractive locations, especially when users travel o...With the rapid development of location-based networks, point-of-interest(POI) recommendation has become an important means to help people discover interesting and attractive locations, especially when users travel out of town. However, because users only check-in interaction is highly sparse, which creates a big challenge for POI recommendation. To tackle this challenge, we propose a joint probabilistic generative model called geographical temporal social content popularity(GTSCP) to imitate user check-in activities in a process of decision making, which effectively integrates the geographical influence, temporal effect, social correlation, content information and popularity impact factors to overcome the data sparsity, especially for out-of-town users. Our proposed the GTSCP supports two recommendation scenarios in a joint model, i.e., home-town recommendation and out-of-town recommendation. Experimental results show that GTSCP achieves significantly superior recommendation quality compared to other state-of-the-art POI recommendation techniques.展开更多
文摘Social media have dramatically changed the mode of information dissemination.Various models and algorithms have been developed to model information diffusion and address the influence maximization problem in complex social networks.However,it appears difficult for state-of-the-art models to interpret complex and reversible real interactive networks.In this paper,we propose a novel influence diffusion model,i.e.,the Operator-Based Model(OBM),by leveraging the advantages offered from the heat diffusion based model and the agent-based model.The OBM improves the performance of simulated dissemination by considering the complex user context in the operator of the heat diffusion based model.The experiment obtains a high similarity of the OBM simulated trend to the real-world diffusion process by use of the dynamic time warping method.Furthermore,a novel influence maximization algorithm,i.e.,the Global Topical Support Greedy algorithm(GTS-Greedy algorithm),is proposed corresponding to the OBM.The experimental results demonstrate its promising performance by comparing it against other classic algorithms.
文摘The modified shear lag model proposed recently was applied to calculate thermal residual stresses and subsequent stress distributions under tensile and compressive loadings. The expressions for the elastic moduli and the yield strengths under tensile and compressive loadings were derived which take account of thermal residual stresses. The asymmetries in the elastic modulus and the yield strength were interpreted using the derived expressions and the obtained results of the stress calculations. The model predictions have exhibited good agreements with the experimental results and also with the other theoretical predictions
基金National Social Science Foundation of China(No.14BTQ030)
文摘Based on risk social cognition theory and planned behavior theory, the influence factors of the public participation in the nanotechnology risk communication are analyzed,and the concept model is presented to analyze their relationships and functional mechanism. In the model,the risk communication behaviors are divided into two variables of the public opinion expression and information acquisition,and the subjective norm divided into the internal and external social networks. Then the questionnaire is designed so as to verify the proposed model and analyze their relationships. The survey data are analyzed using SMART PLS software. The validity analysis shows that the questionnaire has a high convergence and discriminant validity. In addition, the Cronbach'a coefficient of each item is more than 0. 70,which shows the questionnaire has a high credibility. Based on the statistical data analysis, relationships of the influence factors are obtained.Further,the influence path model of the public attitude,intention,self regulation and behavior control in the risk communication is established. According to the Bootstrap algorithm in SMART,the path coefficient and its explanation variance of each influence factor are obtained. The calculation results show that the explanation variance values are all bigger than 10% and the path is reliable.Based on the path model, the influence path and function relationships of the participation attitude, subjective norm and behavior control on the participation intention and behavior are obtained. This will provide theoretical and data supports for the risk management and strategy making of the public participation in nanotechnology risk communication.
基金supported Fundación Reina Sofía Grant PI0006-08 to LTby Ministerio de Ciencia y Tecnología(ES)grant BFU2008-04683-C02-02 to LT
文摘Amyloid peptide(Aβ)oligomers are considered one of the primary causal factors for the synaptic loss characteristic of Alzheimer’s disease(AD)(Karran and De Strooper,2016).However,Aβis generated in normal brains and accumulates at synaptic sites,which raises the question whether Aβplays a physiological role in synapses.
基金Funded by the National Natural Science Foundation of China(Nos.51278304,U1134209,U1434204&51422814)the National Basic Research Program(973 Program)of China(No.011-CB013604)the Technology Research and Development Program(Basic Research Project)of Shenzhen(Nos.JCYJ20120613174456685&JCYJ20130329143859418)
文摘Diffusion has been systematically described as the main mechanism of chloride transport in reinforced concrete(RC) structure, especially when the concrete is in a saturated state. However, the single mechanism of diffusion is not able to describe the actual chloride ingress in the nonsaturated concrete. Instead, it is dominated by the interaction of diffusion and convection. With the synergetic effects of various factors taken into account, this study aimed to modify and develop an analytical convection- diffusion coupling model for chloride transport in nonsaturated concrete. The model was verified by simulation of laboratory tests and field measurement. The results of comparison study demonstrate that the analytical model developed in this study is efficient and accurate in predicting the chloride profiles in the nonsaturated concrete.
文摘During the experiment of gas/liquid coaxial swirl injector conducted with air and water under atmosphere environment, it is observed that the injector may selfoscillate. The self oscillation periodically occurs and vanishes with the increasing velocity of the gas flow.A theoretical model is presented based on the experiment investigation. Simulation of the acoustic process has been performed and conclusions consistent with the experiment can be drawn from the theoretical model, which explains the exPeriment phenomena quite well. At last, the comparison between phenomena of the self oscillation and some experiments of LRE indicates that some instability phenomena in oxygen/hydrogen propellant rocket engine may be the related to self oscillation in coaxial injectors
基金supported by the National Natural Science Foundation of China(Nos.52176032,51976005 and 52006002)the Advanced Jet Propulsion Creativity Center,China(No.HKCX2020-02-013)+2 种基金the National Science and Technology Major Project,China(Nos.2017-II-0004-0016 and 2017-II-0005-0018)the Fundamental Research Funds for the Central Universities,Chinathe Beijing Nova Program,China。
文摘Streamwise Body Force Model(SBFM)could be used to simulate the force of blade on the airflow,resulting in rapid propulsion-airframe integrated simulation.However,when subjected to inlet distortion,the upstream flow field of fan stage is redistributed,which causes inaccurate prediction of fan stage performance.As inspired by the upstream influence of compressor,this paper aims to present a modification strategy for SBFM method to predict the compressor performance under circumferential inlet distortion without any knowledge of compressor geometry.Based on the linearized motion equation,the Upstream Influence Model(UIM)is introduced to predict the upstream flow field redistribution.Then the theoretical Mach number at Aerodynamic Interface Plane(AIP)position is calculated and selected to determine the corresponding body force coefficients based on the functional relationship between body force coefficients and Mach number,thus the upstream influence of compressor could be accurately quantified and the Modified Streamwise Body Force Model(MSBFM)could be established.Two studied cases are calculated with different methods and the upstream flow fields are analyzed.The prediction error of MSBFM method for compressor adiabatic efficiency is less than 3%,and the calculation efficiency is improved 20 times under the condition of ensuring computing accuracy.The MSBFM method has the potential for rapid propulsion-airframe integrated simulation.
基金supported by the National Key Project of Scientific and Technical Supporting Programs of China(2014BAK15B01)
文摘With the rapid development of location-based networks, point-of-interest(POI) recommendation has become an important means to help people discover interesting and attractive locations, especially when users travel out of town. However, because users only check-in interaction is highly sparse, which creates a big challenge for POI recommendation. To tackle this challenge, we propose a joint probabilistic generative model called geographical temporal social content popularity(GTSCP) to imitate user check-in activities in a process of decision making, which effectively integrates the geographical influence, temporal effect, social correlation, content information and popularity impact factors to overcome the data sparsity, especially for out-of-town users. Our proposed the GTSCP supports two recommendation scenarios in a joint model, i.e., home-town recommendation and out-of-town recommendation. Experimental results show that GTSCP achieves significantly superior recommendation quality compared to other state-of-the-art POI recommendation techniques.