Engineering change management is a special form of problem solving where many rules must be followed to satisfy the requirements of product changes.As engineering change has great influence on the cycle and the cost o...Engineering change management is a special form of problem solving where many rules must be followed to satisfy the requirements of product changes.As engineering change has great influence on the cycle and the cost of product development,it is necessary to anticipate design changes(DCs)in advance and estimate the influence effectively.A process simulation-based method for engineering change management is proposed incorporating multiple assessment parameters.First,the change propagation model is established,which includes the formulation of change propagation influence,assessment score of DC solution.Then the optimization process of DC solution is introduced based on ant colony optimization(ACO),and an optimization algorithm is detailed to acquire the optimal DC solution automatically.Finally,a case study of belt conveyor platform is implemented to validate the proposed method.The results show that changed requirement of product can be satisfied by multiple DC solutions and the optimal one can be acquired according to the unique characteristics of each solution.展开更多
In this paper,an improved Susceptible-Infected-Susceptible(SIS) epidemic spreading model is proposed in order to provide a theoretical method to analyze and predict the spreading of diseases.This model is based on the...In this paper,an improved Susceptible-Infected-Susceptible(SIS) epidemic spreading model is proposed in order to provide a theoretical method to analyze and predict the spreading of diseases.This model is based on the following ideas:in social networks,the contact probability between nodes is decided by their social distances and their active degrees.The contact probability of two indirectly connected nodes is decided by the shortest path between them.Theoretical analysis and simulation experiment were conducted to evaluate the performance of this improved model.Because the proposed model is independent of the network structure,simulation experiments were done in several kinds of networks,namely the ER network,the random regular network,the WS small world network,and the BA scale-free network,in order to study the influences of certain factors have on the epidemic spreading,such as the social contact active degree,the network structure,the average degree,etc.This improved model provides an idea for studying the spreading rule of computer virus,attitudes,fashion styles and public opinions in social networks.展开更多
Computer simulation models are widely applied in various areas of the health care sector, including the spread of infectious diseases. Patch models involve explicit movements of people between distinct locations. The ...Computer simulation models are widely applied in various areas of the health care sector, including the spread of infectious diseases. Patch models involve explicit movements of people between distinct locations. The aim of the present work has been designed and explored a patch model with population mobility between different patches and between each patch and an external population. The authors considered a SIR （susceptible-infected-recovered） scheme. The model was explored by computer simulations. The results show how endemic levels are reached in all patches of the system. Furthermore, the performed explorations suggest that the people mobility between patches, the immigration from outside the system and the infection rate in each patch, are factors that may influence the dynamics of epidemics and should be considered in health policy planning.展开更多
Based on the Navier-Stokes Equations (NSE), numerical simulation with fine grids is conducted to simulate the coastal surface wave changes, including wave generation, propagation, transformation and interactions betwe...Based on the Navier-Stokes Equations (NSE), numerical simulation with fine grids is conducted to simulate the coastal surface wave changes, including wave generation, propagation, transformation and interactions between waves and structures. This numerical model has been tested for the generation of the desired incident waves, including both regular and random waves. Some numerical results of this model are compared with available experimental data. In order to apply this model to actual cases, boundary conditions are considered in detail for different shoreline types (beach or breakwater, slope or vertical wall, etc. ). Finally, the utility of the model to a real coastal area is shown by applying it to a fishing port located in Shidao, Rongcheng, Shandong Province, P.R. China.展开更多
We report the oscillating propagation of kink in a nondissipative Frenkel-Kontorova （FK） chain driven by external DC force, which is different from the usual propagation of localized modes with equal speed. When the...We report the oscillating propagation of kink in a nondissipative Frenkel-Kontorova （FK） chain driven by external DC force, which is different from the usual propagation of localized modes with equal speed. When the kink moves in the opposite direction of the external DC force, the kink will be accelerated and the potential of the FK chain in the external force field is transformed to be the kinetic energy of the kink. If the kink reaches the boundary of the FK chain, the kink will be bounced back and moves in the opposite direction, then the kink will be decelerated gradually and the kinetic energy of the kink ＆ transformed to be the potential of the FK chain in the external force field. If the speed of the kink reaches zero, the kink will move in the opposite direction again driven by the external DC force, and a new oscillating cycle begins. Simulation result demonstrates exactly the transformation between the kinetic energy of the kink and the potential of the FK chain in the external force field. The interesting energy exchange is induced by the special topology of kinks, and other localized modes, such as breathers and envelope solitons, have no the interesting phenomenon.展开更多
Based on the research of Lynett and Liu, the horizontal fully two-dimensional, depth-integrated model for the internal wave propagation is re-deduced. By combining this model with the M4S model, the propagation proces...Based on the research of Lynett and Liu, the horizontal fully two-dimensional, depth-integrated model for the internal wave propagation is re-deduced. By combining this model with the M4S model, the propagation process of the internal waves is simulated in Synthetic Aperture Radar （SAR） images. The simulation results clearly show the bottom effects during the propagation such as fission and isobaths-parallelized propagation direction. This simulation procedure can lay the foundation for the quantitative interpretation of internal waves from fully two-dimensional SAR images.展开更多
基金supported by the National Natural Science Foundation of China(No.51805253)Research Start-up Fund Project of Introduced Talent(No.YKJ201969)Equipment Project of Ship Assembly and Construction for the Ministry of Industry and Information Technology(No.TC190H47J)。
文摘Engineering change management is a special form of problem solving where many rules must be followed to satisfy the requirements of product changes.As engineering change has great influence on the cycle and the cost of product development,it is necessary to anticipate design changes(DCs)in advance and estimate the influence effectively.A process simulation-based method for engineering change management is proposed incorporating multiple assessment parameters.First,the change propagation model is established,which includes the formulation of change propagation influence,assessment score of DC solution.Then the optimization process of DC solution is introduced based on ant colony optimization(ACO),and an optimization algorithm is detailed to acquire the optimal DC solution automatically.Finally,a case study of belt conveyor platform is implemented to validate the proposed method.The results show that changed requirement of product can be satisfied by multiple DC solutions and the optimal one can be acquired according to the unique characteristics of each solution.
基金supported by National Natural Science Foundation of China 61301091Shaanxi Province Science and Technology Project 2015GY015
文摘In this paper,an improved Susceptible-Infected-Susceptible(SIS) epidemic spreading model is proposed in order to provide a theoretical method to analyze and predict the spreading of diseases.This model is based on the following ideas:in social networks,the contact probability between nodes is decided by their social distances and their active degrees.The contact probability of two indirectly connected nodes is decided by the shortest path between them.Theoretical analysis and simulation experiment were conducted to evaluate the performance of this improved model.Because the proposed model is independent of the network structure,simulation experiments were done in several kinds of networks,namely the ER network,the random regular network,the WS small world network,and the BA scale-free network,in order to study the influences of certain factors have on the epidemic spreading,such as the social contact active degree,the network structure,the average degree,etc.This improved model provides an idea for studying the spreading rule of computer virus,attitudes,fashion styles and public opinions in social networks.
文摘Computer simulation models are widely applied in various areas of the health care sector, including the spread of infectious diseases. Patch models involve explicit movements of people between distinct locations. The aim of the present work has been designed and explored a patch model with population mobility between different patches and between each patch and an external population. The authors considered a SIR （susceptible-infected-recovered） scheme. The model was explored by computer simulations. The results show how endemic levels are reached in all patches of the system. Furthermore, the performed explorations suggest that the people mobility between patches, the immigration from outside the system and the infection rate in each patch, are factors that may influence the dynamics of epidemics and should be considered in health policy planning.
基金supported by the National Natural Foundation of China(No.50479027)the Natural Science Foundation of Qingdao(Grant No.03-jr-15).
文摘Based on the Navier-Stokes Equations (NSE), numerical simulation with fine grids is conducted to simulate the coastal surface wave changes, including wave generation, propagation, transformation and interactions between waves and structures. This numerical model has been tested for the generation of the desired incident waves, including both regular and random waves. Some numerical results of this model are compared with available experimental data. In order to apply this model to actual cases, boundary conditions are considered in detail for different shoreline types (beach or breakwater, slope or vertical wall, etc. ). Finally, the utility of the model to a real coastal area is shown by applying it to a fishing port located in Shidao, Rongcheng, Shandong Province, P.R. China.
基金supported by Scientific Research Fund of Hunan Provincial Education Department under Grant No. 07B075Interactive Project Fund of Xiangtan University under Grant No. 061ND09Dr. Shangyou Zeng's Initial Scientific Research Fund of Xiangtan University
文摘We report the oscillating propagation of kink in a nondissipative Frenkel-Kontorova （FK） chain driven by external DC force, which is different from the usual propagation of localized modes with equal speed. When the kink moves in the opposite direction of the external DC force, the kink will be accelerated and the potential of the FK chain in the external force field is transformed to be the kinetic energy of the kink. If the kink reaches the boundary of the FK chain, the kink will be bounced back and moves in the opposite direction, then the kink will be decelerated gradually and the kinetic energy of the kink ＆ transformed to be the potential of the FK chain in the external force field. If the speed of the kink reaches zero, the kink will move in the opposite direction again driven by the external DC force, and a new oscillating cycle begins. Simulation result demonstrates exactly the transformation between the kinetic energy of the kink and the potential of the FK chain in the external force field. The interesting energy exchange is induced by the special topology of kinks, and other localized modes, such as breathers and envelope solitons, have no the interesting phenomenon.
文摘Based on the research of Lynett and Liu, the horizontal fully two-dimensional, depth-integrated model for the internal wave propagation is re-deduced. By combining this model with the M4S model, the propagation process of the internal waves is simulated in Synthetic Aperture Radar （SAR） images. The simulation results clearly show the bottom effects during the propagation such as fission and isobaths-parallelized propagation direction. This simulation procedure can lay the foundation for the quantitative interpretation of internal waves from fully two-dimensional SAR images.
