关于钕铁硼(Nd Fe B)氢粉碎生产过程优化控制的研究,根据传统工艺过程机理建立的动态机理模型不能精确的反应真实氢碎状态。提出了面向复杂非线性过程的基于增强学习的神经网络优化模型和采用NLMS算法的Volterra级数自适应优化模型,分...关于钕铁硼(Nd Fe B)氢粉碎生产过程优化控制的研究,根据传统工艺过程机理建立的动态机理模型不能精确的反应真实氢碎状态。提出了面向复杂非线性过程的基于增强学习的神经网络优化模型和采用NLMS算法的Volterra级数自适应优化模型,分别利用上述两种模型对机理模型进行优化,输出合金氢含量、温度和压力的预测值,最后,通过实验验证了两种模型的有效性。实验结果表明,采用Volterra级数的优化模型对机理模型的优化效果更好,为实时优化控制钕铁硼氢粉碎过程提供了科学依据。展开更多
Identifying the flow patterns is vital for understanding the complicated physical mechanisms in multiphase flows.For this purpose,electrical capacitance tomography(ECT) technique is considered as a promising visualiza...Identifying the flow patterns is vital for understanding the complicated physical mechanisms in multiphase flows.For this purpose,electrical capacitance tomography(ECT) technique is considered as a promising visualization method for the flow pattern identification,in which image reconstruction algorithms play an important role.In this paper,a generalized dynamic reconstruction model,which integrates ECT measurement information and physical evolution information of the objects of interest,was presented.A generalized objective functional that simultaneously considers the spatial constraints,temporal constraints and dynamic evolution information of the objects of interest was proposed.Numerical simulations and experiments were implemented to evaluate the feasibility and efficiency of the proposed algorithm.For the cases considered in this paper,the proposed algorithm can well reconstruct the flow patterns,and the quality of the reconstructed images is improved,which indicates that the proposed algorithm is competent to reconstruct the flow patterns in the visualization of multiphase flows.展开更多
In multi-agent systems(MAS),finding agents which are able to service properly in an open and dynamic environment are the key issue in problem solving.However,it is difficult to find agent resources quickly and positio...In multi-agent systems(MAS),finding agents which are able to service properly in an open and dynamic environment are the key issue in problem solving.However,it is difficult to find agent resources quickly and position agents accurately and complete the system integration by the keyword matching method,due to the lack of clear semantic information of the classical agent model.An semantic-based agent dynamic positioning mechanism was proposed to assist in the system dynamic integration.According to the semantic agent model and the description method,a two-stage process including the domain positioning stage and the service semantic matching positioning stage,was discussed.With this mechanism,proper agents that provide appropriate service to assign sub-tasks for task completion can be found quickly and accurately.Finally,the effectiveness of the positioning mechanism was validated through the in-depth performance analysis in the application of simulation experiments to the system dynamic integration.展开更多
Objective To investigate the pathological mechanism of hip dysplasia. Methods The leftknee joints of eighteen rabbits were fixed in extending position with plaster cylinder for four weeks, but their hip joints were fl...Objective To investigate the pathological mechanism of hip dysplasia. Methods The leftknee joints of eighteen rabbits were fixed in extending position with plaster cylinder for four weeks, but their hip joints were flexed. The right side served as control. Roentgenogram was made in all animals. The changes of the x-ray films and the pathological findings between left and right hips were compared. Results Appearance of hip dysplasia was obvious at four weeks after plaster fixation. There were pathological changes, including shallow ace-tabulum and flat femoral head, increased acetabular index and decreased acetabular head index on the x-ray films. Conclusion The hip dysplasia is the result of prolonged extending position of the knee joint. Abnormal knee posture seems to be one of the important factors of hip dysplasia. This kind of deformation may be worsened with time.展开更多
It has been widely believed that trust is the basis for on-line trading by both academia and practice. The process of f initial trust formation is a dynamic and repeated process. In the electric business environment, ...It has been widely believed that trust is the basis for on-line trading by both academia and practice. The process of f initial trust formation is a dynamic and repeated process. In the electric business environment, this work chose to research the first phase of the process, which is initial trust. The Writer established dynamic model of initial trust formation biased on theory of planned behavior with other theories, such as TAM and social exchange theory, after micro-analyzing this formation mechanism from. in order to confirming effectiveness of the dynamic model, the writer adopted empirical study, from which writer got an order of. From the result of empirical study, we got the strength order of main factors that can influence the establishment of initial trust.展开更多
文摘关于钕铁硼(Nd Fe B)氢粉碎生产过程优化控制的研究,根据传统工艺过程机理建立的动态机理模型不能精确的反应真实氢碎状态。提出了面向复杂非线性过程的基于增强学习的神经网络优化模型和采用NLMS算法的Volterra级数自适应优化模型,分别利用上述两种模型对机理模型进行优化,输出合金氢含量、温度和压力的预测值,最后,通过实验验证了两种模型的有效性。实验结果表明,采用Volterra级数的优化模型对机理模型的优化效果更好,为实时优化控制钕铁硼氢粉碎过程提供了科学依据。
基金Supported by the National Natural Science Foundation of China (50736002,50806005,51006106)the Program for Changjiang Scholars and Innovative Research Team in University (IRT0952)
文摘Identifying the flow patterns is vital for understanding the complicated physical mechanisms in multiphase flows.For this purpose,electrical capacitance tomography(ECT) technique is considered as a promising visualization method for the flow pattern identification,in which image reconstruction algorithms play an important role.In this paper,a generalized dynamic reconstruction model,which integrates ECT measurement information and physical evolution information of the objects of interest,was presented.A generalized objective functional that simultaneously considers the spatial constraints,temporal constraints and dynamic evolution information of the objects of interest was proposed.Numerical simulations and experiments were implemented to evaluate the feasibility and efficiency of the proposed algorithm.For the cases considered in this paper,the proposed algorithm can well reconstruct the flow patterns,and the quality of the reconstructed images is improved,which indicates that the proposed algorithm is competent to reconstruct the flow patterns in the visualization of multiphase flows.
基金Projects(61173026,61373045,61202039)supported by the National Natural Science Foundation of ChinaProject(2012AA02A603)supported by the National High Technology Research and Development Program of China+1 种基金Projects(K5051223008,K5051223002)supported by the Fundamental Research Funds for the Central Universities of ChinaProject(513***103E)supported by the Pre-Research Project of the"Twelfth Five-Year-Plan"of China
文摘In multi-agent systems(MAS),finding agents which are able to service properly in an open and dynamic environment are the key issue in problem solving.However,it is difficult to find agent resources quickly and position agents accurately and complete the system integration by the keyword matching method,due to the lack of clear semantic information of the classical agent model.An semantic-based agent dynamic positioning mechanism was proposed to assist in the system dynamic integration.According to the semantic agent model and the description method,a two-stage process including the domain positioning stage and the service semantic matching positioning stage,was discussed.With this mechanism,proper agents that provide appropriate service to assign sub-tasks for task completion can be found quickly and accurately.Finally,the effectiveness of the positioning mechanism was validated through the in-depth performance analysis in the application of simulation experiments to the system dynamic integration.
文摘Objective To investigate the pathological mechanism of hip dysplasia. Methods The leftknee joints of eighteen rabbits were fixed in extending position with plaster cylinder for four weeks, but their hip joints were flexed. The right side served as control. Roentgenogram was made in all animals. The changes of the x-ray films and the pathological findings between left and right hips were compared. Results Appearance of hip dysplasia was obvious at four weeks after plaster fixation. There were pathological changes, including shallow ace-tabulum and flat femoral head, increased acetabular index and decreased acetabular head index on the x-ray films. Conclusion The hip dysplasia is the result of prolonged extending position of the knee joint. Abnormal knee posture seems to be one of the important factors of hip dysplasia. This kind of deformation may be worsened with time.
文摘It has been widely believed that trust is the basis for on-line trading by both academia and practice. The process of f initial trust formation is a dynamic and repeated process. In the electric business environment, this work chose to research the first phase of the process, which is initial trust. The Writer established dynamic model of initial trust formation biased on theory of planned behavior with other theories, such as TAM and social exchange theory, after micro-analyzing this formation mechanism from. in order to confirming effectiveness of the dynamic model, the writer adopted empirical study, from which writer got an order of. From the result of empirical study, we got the strength order of main factors that can influence the establishment of initial trust.
