In chemical processes, fault diagnosis is relatively difficult due to the incomplete prior-knowledge and unpredictable production changes. To solve the problem, a case-based extension fault diagnosis (CEFD) method is ...In chemical processes, fault diagnosis is relatively difficult due to the incomplete prior-knowledge and unpredictable production changes. To solve the problem, a case-based extension fault diagnosis (CEFD) method is proposed combining with extension theory, in which the basic-element model is used for the unified and deep fault description, the distance concept is applied to quantify the correlation degree between the new fault and the original fault cases, and the extension transformation is used to expand and obtain the solution of unknown faults. With the application in Tennessee Eastman process, the result indicates that CEFD method has a flexible fault representation, objective fault retrieve performance and good ability for fault study, providing a new way for diagnosing production faults accurately.展开更多
The experiments of one-stage semi-circular and two-stage semi-circular impinging stream drying as well as the vertical and semi-circular combined impinging stream drying were carried out. The velocity distribution and...The experiments of one-stage semi-circular and two-stage semi-circular impinging stream drying as well as the vertical and semi-circular combined impinging stream drying were carried out. The velocity distribution and the mean residence time of particles, and the influence of various factors on drying characteristics were studied. A mathematical model of granular material drying in a semi-circular impinging stream dryer was proposed, in which the flow characteristics as well as the heat and mass transfer mechanisms were considered. Reasonable numerical methods were used to solve the equations. Under various conditions, the calculated results agree well with the experimental data. The unsteady-state drying dynamic equation, as well as the variations of drying rate and moisture content versus time were obtained. The results indicate that constant drying rate period does not exist in a semi-circular impinging stream dryer. Appropriate semi-circular stage number and curvature radius, flow-rate ratio, air velocity, and higher inlet air temperature should be used for enhancing the drying process.展开更多
Utilizing the acoustic emission(AE) technique, an experimental investigation into the damage evolution for steel strand under axial tension was described. The damage evolution model for steel stand relating the damage...Utilizing the acoustic emission(AE) technique, an experimental investigation into the damage evolution for steel strand under axial tension was described. The damage evolution model for steel stand relating the damage evolution to acoustic emission parameters was proposed by incorporating the AE rate process theory. The AE monitoring results indicate that damages occur in both elastic and plastic phases of steel strand. In elastic phase, AE signals are mainly sent out from the micro damage due to the surface friction among the wires of steel strand, while in plastic phase, AE signals emitted from the plastic deformation of wires. In addition, the AE cumulative parameters curves closely resemble the loading curve. The AE cumulative parameters curves can well describe the damage evolution process including the damage occurrence and damage development for steel strands. It is concluded that the AE technique is an effective and useful nondestructive technique for evaluating the damage characteristics of steel strand.展开更多
Local inhomogeneity in totally asymmetric simple exclusion processes (TASEPs) with different hopping rates was studied. Many biological and chemical phenomena can be described by these non-equilibrium processes. A s...Local inhomogeneity in totally asymmetric simple exclusion processes (TASEPs) with different hopping rates was studied. Many biological and chemical phenomena can be described by these non-equilibrium processes. A simple approximate theory and extensive Monte Carlo computer simulations were used to calculate the steady-state phase diagrams and bulk densities. It is found that the phase diagram for local inhomogeneity in TASEP with different hopping rates p is qualitatively similar to homogeneous models. Interestingly, there is a saturation point pair (a*, fl*) for the system, which is decided by parameters p and q. There are three stationary phases in the system, when parameter p is fixed (i.e., p=0.8), with the increase of the parameter q, the region of LD/LD and HD/HD phase increases and the HD/LD is the only phase which the region shrinks. The analytical results are in good agreement with simulations.展开更多
During the evolution from cognitive radio to cognitive networks,the environment cognition extended from wireless environments to network and user environments.To understand the basic theory of Local Multi-Domain Cogni...During the evolution from cognitive radio to cognitive networks,the environment cognition extended from wireless environments to network and user environments.To understand the basic theory of Local Multi-Domain Cognition(LMDC),and to provide a theoretical basis for further study in cooperative multi-domain cognition and initiative multi-domain cognition,the LMDC is investigated in this paper.A Local Single-Domain Cognitive(LSDC)approach is first proposed based on multidimensional edge detection theory.This approach can divide the parameter space that describes the single-domain environment into different areas,and can represent each area with an identifier.Using this as a foundation,the single-domain environment is extended to multi-domain environments,and an LMDC approach is presented to describe the LMDC environment.The paper concludes by introducing two examples and the corresponding analysis to illustrate the feasibility of the proposed LMDC approach.展开更多
Existing theories of the globalisation of firms fall short of integrating evolutionary, self-reproductive mechanisms. This conceptual paper serves to provide an overview on existing literature in systems theory and to...Existing theories of the globalisation of firms fall short of integrating evolutionary, self-reproductive mechanisms. This conceptual paper serves to provide an overview on existing literature in systems theory and to develop a basic framework for the study of evolutionary processes in the globalisation of firms. Ontological, epistemological, and methodological consequences of an evolutionary social systems approach to globalisation will be discussed.展开更多
Based on the theory of random process and the characteristic of the functioning of a system component subject to a certain specific probability distribution, emulated the whole process of system production on Iongwall...Based on the theory of random process and the characteristic of the functioning of a system component subject to a certain specific probability distribution, emulated the whole process of system production on Iongwall face was emulated, in which the methods of time pace and computer random emulation were adopted. The paper provides an objective basis for the analysis of a mining Iongwall face and the varied lines of effectiveness, machine stoppage rate and coal flow of components and system, and output etc.lt also offers some theories to improve productivity by discussing the application of the transformation plan and optimization of reasonable coal stock capacity, as well as selection of system equipment and matching optimization.展开更多
The interaction between radionuclides and solid/water interfaces is important to understand the physicochemical processes of radionuclides in the natural environment.Herein,the interaction of 60Co(Ⅱ) with TiO 2 in aq...The interaction between radionuclides and solid/water interfaces is important to understand the physicochemical processes of radionuclides in the natural environment.Herein,the interaction of 60Co(Ⅱ) with TiO 2 in aqueous solution as a function of pH and ionic strength was studied by using batch technique combined with surface complexation model and density functional theory(DFT) calculations.The batch experimental results showed that the adsorption of 60Co(Ⅱ) was dependent on pH and independent of ionic strength,indicating the formation of inner-sphere surface complexes on TiO 2 surfaces.The results of surface complexation models and DFT calculations indicated that the surface species of 60Co(Ⅱ) adsorbed on TiO 2 followed the trend:B structure(i.e.,60Co(Ⅱ) was linked to one bridge oxygen site) was the dominant surface species at low pH,and TT structure(i.e.,60Co(Ⅱ) was linked to two terminal oxygen sites) became the important surface complex at neutral and alkaline pH values.These results demonstrated that a multi-technique approach could lead to definitive information on the structures of adsorbed 60Co(Ⅱ) at the molecular level at the TiO 2 /water interfaces,as well as realistic models to rationalize and accurately evaluate the macroscopic manifestations of radionuclide adsorption phenomena.展开更多
The W UMa-type contact binaries have been observed for several decades.To construct the evolutionary model for W UMa-type contact binaries,many difficulties were encountered due to the existence of complicated physica...The W UMa-type contact binaries have been observed for several decades.To construct the evolutionary model for W UMa-type contact binaries,many difficulties were encountered due to the existence of complicated physical processes in such systems.The model introduced by Huang,Song and Bi includes some special and unique understandings of the physical processes of contact binaries.It is necessary to test whether this model can be used for W UMa-type contact binaries.The best way to test a theoretical model is to know whether this model can explain the observational phenomena of such systems.For this aim,a comparison is performed for the relations of mass-luminosity,mass-radius,and the distribution in the HR diagram obtained from the model introduced by Huang et al.and those from the astronomical observations.The result of the comparison indicates that this model can be applied to W UMa-type contact binaries and can explain the observational phenomena of such binaries.展开更多
Porous poly(vinylidene fluoride)(PVDF)/poly(methyl methacrylate)(PMMA) blend five-bore hollow fiber membranes are prepared by wet phase inversion methods.In spinning these PVDF hollow fibers, N,N-dimethylacetamide(DMA...Porous poly(vinylidene fluoride)(PVDF)/poly(methyl methacrylate)(PMMA) blend five-bore hollow fiber membranes are prepared by wet phase inversion methods.In spinning these PVDF hollow fibers, N,N-dimethylacetamide(DMAc) and polyvinyl pyrrolidone(PVP) are used as the solvent and the non-solvent additive,respectively.The external coagulant uses water.The internal coagulants use water and DMAc-water solutions.The membranes are characterized in terms of water flux and molecular weight cut-off for the wet membranes.The cross-sectional structures are examined by scanning electron microscopy(SEM).The effects of polymer concentration and the internal coagulant on the permeation properties and membrane structures are examined keeping the bore liquid flow and air-gap constants.Relative high flux,rejection and strengh PVDF five-bore hollow fiber membranes could be prepared from the polymer concentration in dope solution at 17%of mass fraction,the air gap distance of 14 cm,and using 10%of mass fraction of DMAc solution as the internal coagulant at 13 mL/min of flow.展开更多
基金Supported by the National Natural Science Foundation of China (61104131).
文摘In chemical processes, fault diagnosis is relatively difficult due to the incomplete prior-knowledge and unpredictable production changes. To solve the problem, a case-based extension fault diagnosis (CEFD) method is proposed combining with extension theory, in which the basic-element model is used for the unified and deep fault description, the distance concept is applied to quantify the correlation degree between the new fault and the original fault cases, and the extension transformation is used to expand and obtain the solution of unknown faults. With the application in Tennessee Eastman process, the result indicates that CEFD method has a flexible fault representation, objective fault retrieve performance and good ability for fault study, providing a new way for diagnosing production faults accurately.
基金Supported by the State Key Fundamental Research Plan of China (No. G20000263) and the Director Foundation of Institute of Engineering Thermophysics, Chinese Academy of Sciences.
文摘The experiments of one-stage semi-circular and two-stage semi-circular impinging stream drying as well as the vertical and semi-circular combined impinging stream drying were carried out. The velocity distribution and the mean residence time of particles, and the influence of various factors on drying characteristics were studied. A mathematical model of granular material drying in a semi-circular impinging stream dryer was proposed, in which the flow characteristics as well as the heat and mass transfer mechanisms were considered. Reasonable numerical methods were used to solve the equations. Under various conditions, the calculated results agree well with the experimental data. The unsteady-state drying dynamic equation, as well as the variations of drying rate and moisture content versus time were obtained. The results indicate that constant drying rate period does not exist in a semi-circular impinging stream dryer. Appropriate semi-circular stage number and curvature radius, flow-rate ratio, air velocity, and higher inlet air temperature should be used for enhancing the drying process.
基金Projects(51308073,51378081)supported by the National Natural Science Foundation of ChinaProject(20124316120002)supported by PhD Programs Foundation of Ministry of Education of China+1 种基金Project(12KB02)supported by the Key Laboratory for Safety Control of Bridge Engineering of Ministry of Education of ChinaProject(14JJ3087)supported by the Science Foundation of Hunan Province,China
文摘Utilizing the acoustic emission(AE) technique, an experimental investigation into the damage evolution for steel strand under axial tension was described. The damage evolution model for steel stand relating the damage evolution to acoustic emission parameters was proposed by incorporating the AE rate process theory. The AE monitoring results indicate that damages occur in both elastic and plastic phases of steel strand. In elastic phase, AE signals are mainly sent out from the micro damage due to the surface friction among the wires of steel strand, while in plastic phase, AE signals emitted from the plastic deformation of wires. In addition, the AE cumulative parameters curves closely resemble the loading curve. The AE cumulative parameters curves can well describe the damage evolution process including the damage occurrence and damage development for steel strands. It is concluded that the AE technique is an effective and useful nondestructive technique for evaluating the damage characteristics of steel strand.
基金Project(2011FZ050) supported by Applied Basic Research Program of Yunnan Provincial Science and Technology Department,ChinaProject(2011J084) supported by Master Program of Yunnan Province Education Department,China
文摘Local inhomogeneity in totally asymmetric simple exclusion processes (TASEPs) with different hopping rates was studied. Many biological and chemical phenomena can be described by these non-equilibrium processes. A simple approximate theory and extensive Monte Carlo computer simulations were used to calculate the steady-state phase diagrams and bulk densities. It is found that the phase diagram for local inhomogeneity in TASEP with different hopping rates p is qualitatively similar to homogeneous models. Interestingly, there is a saturation point pair (a*, fl*) for the system, which is decided by parameters p and q. There are three stationary phases in the system, when parameter p is fixed (i.e., p=0.8), with the increase of the parameter q, the region of LD/LD and HD/HD phase increases and the HD/LD is the only phase which the region shrinks. The analytical results are in good agreement with simulations.
基金supported in part by the State Key Program of National Natural Science Foundation of China under Grant No. 61231008the National Natural Science Foundation of China under Grant No. 61072068the program for Cheung Kong Scholars and Innovative Research Team in University under Grant IRT0852
文摘During the evolution from cognitive radio to cognitive networks,the environment cognition extended from wireless environments to network and user environments.To understand the basic theory of Local Multi-Domain Cognition(LMDC),and to provide a theoretical basis for further study in cooperative multi-domain cognition and initiative multi-domain cognition,the LMDC is investigated in this paper.A Local Single-Domain Cognitive(LSDC)approach is first proposed based on multidimensional edge detection theory.This approach can divide the parameter space that describes the single-domain environment into different areas,and can represent each area with an identifier.Using this as a foundation,the single-domain environment is extended to multi-domain environments,and an LMDC approach is presented to describe the LMDC environment.The paper concludes by introducing two examples and the corresponding analysis to illustrate the feasibility of the proposed LMDC approach.
文摘Existing theories of the globalisation of firms fall short of integrating evolutionary, self-reproductive mechanisms. This conceptual paper serves to provide an overview on existing literature in systems theory and to develop a basic framework for the study of evolutionary processes in the globalisation of firms. Ontological, epistemological, and methodological consequences of an evolutionary social systems approach to globalisation will be discussed.
基金Supported by the Special Topics of Major Scientific and Technological Research Projects Shanxi Province (2006031099-01)Youth Science Funds of Shanxi Province (2006021024)Science and Technology Project of Taiyuan City (07010728)
文摘Based on the theory of random process and the characteristic of the functioning of a system component subject to a certain specific probability distribution, emulated the whole process of system production on Iongwall face was emulated, in which the methods of time pace and computer random emulation were adopted. The paper provides an objective basis for the analysis of a mining Iongwall face and the varied lines of effectiveness, machine stoppage rate and coal flow of components and system, and output etc.lt also offers some theories to improve productivity by discussing the application of the transformation plan and optimization of reasonable coal stock capacity, as well as selection of system equipment and matching optimization.
基金Progress of Projects Supported by NSFCsupported by the National Basic Research Program of China (2011CB933700)the National Natural Science Foundation of China (20907055,20971126,21071147,91126020,21077107)
文摘The interaction between radionuclides and solid/water interfaces is important to understand the physicochemical processes of radionuclides in the natural environment.Herein,the interaction of 60Co(Ⅱ) with TiO 2 in aqueous solution as a function of pH and ionic strength was studied by using batch technique combined with surface complexation model and density functional theory(DFT) calculations.The batch experimental results showed that the adsorption of 60Co(Ⅱ) was dependent on pH and independent of ionic strength,indicating the formation of inner-sphere surface complexes on TiO 2 surfaces.The results of surface complexation models and DFT calculations indicated that the surface species of 60Co(Ⅱ) adsorbed on TiO 2 followed the trend:B structure(i.e.,60Co(Ⅱ) was linked to one bridge oxygen site) was the dominant surface species at low pH,and TT structure(i.e.,60Co(Ⅱ) was linked to two terminal oxygen sites) became the important surface complex at neutral and alkaline pH values.These results demonstrated that a multi-technique approach could lead to definitive information on the structures of adsorbed 60Co(Ⅱ) at the molecular level at the TiO 2 /water interfaces,as well as realistic models to rationalize and accurately evaluate the macroscopic manifestations of radionuclide adsorption phenomena.
基金supported by the National Natural Science Foundation of China (Grant No. 10933002)
文摘The W UMa-type contact binaries have been observed for several decades.To construct the evolutionary model for W UMa-type contact binaries,many difficulties were encountered due to the existence of complicated physical processes in such systems.The model introduced by Huang,Song and Bi includes some special and unique understandings of the physical processes of contact binaries.It is necessary to test whether this model can be used for W UMa-type contact binaries.The best way to test a theoretical model is to know whether this model can explain the observational phenomena of such systems.For this aim,a comparison is performed for the relations of mass-luminosity,mass-radius,and the distribution in the HR diagram obtained from the model introduced by Huang et al.and those from the astronomical observations.The result of the comparison indicates that this model can be applied to W UMa-type contact binaries and can explain the observational phenomena of such binaries.
基金the China Postdoctoral Science Foundation (No.20110490645)the Science Foundation of Shanghai(No.11ZR1400800)
文摘Porous poly(vinylidene fluoride)(PVDF)/poly(methyl methacrylate)(PMMA) blend five-bore hollow fiber membranes are prepared by wet phase inversion methods.In spinning these PVDF hollow fibers, N,N-dimethylacetamide(DMAc) and polyvinyl pyrrolidone(PVP) are used as the solvent and the non-solvent additive,respectively.The external coagulant uses water.The internal coagulants use water and DMAc-water solutions.The membranes are characterized in terms of water flux and molecular weight cut-off for the wet membranes.The cross-sectional structures are examined by scanning electron microscopy(SEM).The effects of polymer concentration and the internal coagulant on the permeation properties and membrane structures are examined keeping the bore liquid flow and air-gap constants.Relative high flux,rejection and strengh PVDF five-bore hollow fiber membranes could be prepared from the polymer concentration in dope solution at 17%of mass fraction,the air gap distance of 14 cm,and using 10%of mass fraction of DMAc solution as the internal coagulant at 13 mL/min of flow.