The dynamic model of cold rolling mill based on strip flatness and thickness integrated control was proposed,containing the following sub-models:the rolling process model,the dynamic model of rolls along axial directi...The dynamic model of cold rolling mill based on strip flatness and thickness integrated control was proposed,containing the following sub-models:the rolling process model,the dynamic model of rolls along axial direction,and the compensation model.Based on the rule of volume flow rate,the dynamic rolling process model was built.The work roll and backup roll were taken as elastic continuous bodies,the effect of shear and moment of inertia were taken into consideration,and then the dynamic model of rolls was built.The two models were coupled together,and the dynamic model of rolling mill was built.In the dynamic model,the thermal expansion of the rolls,the wear of the rolls and other related parameters can not be considered.In order to compensate the dynamic model,the coupled static model of rolls and strip was applied.Then,according to the inner relationship of these models,the dynamic model and the compensation model were coupled,and the dynamic model of rolling mill based on the strip flatness and thickness integrated control was built.The dynamic simulation of the rolling process was made,and the dynamic thickness and the dynamic flatness information were obtained.This model not only provides a theory basis for the virtual rolling,but also provides a platform for the application of advanced control theory.展开更多
In order to study dynamic laws of surface movements over coal mines due to mining activities,a dynamic prediction model of surface movements was established,based on the theory of support vector machines(SVM) and time...In order to study dynamic laws of surface movements over coal mines due to mining activities,a dynamic prediction model of surface movements was established,based on the theory of support vector machines(SVM) and times-series analysis.An engineering application was used to verify the correctness of the model.Measurements from observation stations were analyzed and processed to obtain equal-time interval surface movement data and subjected to tests of stationary,zero means and normality.Then the data were used to train the SVM model.A time series model was established to predict mining subsidence by rational choices of embedding dimensions and SVM parameters.MAPE and WIA were used as indicators to evaluate the accuracy of the model and for generalization performance.In the end,the model was used to predict future surface movements.Data from observation stations in Huaibei coal mining area were used as an example.The results show that the maximum absolute error of subsidence is 9 mm,the maximum relative error 1.5%,the maximum absolute error of displacement 7 mm and the maximum relative error 1.8%.The accuracy and reliability of the model meet the requirements of on-site engineering.The results of the study provide a new approach to investigate the dynamics of surface movements.展开更多
To deploy sensor nodes over the area of interest,a scheme,named node scattering manipulation,was proposed.It adopted the following method:during node scattering,the initial states of every node,including the velocity ...To deploy sensor nodes over the area of interest,a scheme,named node scattering manipulation,was proposed.It adopted the following method:during node scattering,the initial states of every node,including the velocity and direction,were manipulated so that it would land in a region with a certain probability;every sensor was relocated in order to improve the coverage and connectivity.Simultaneously,to easily analyze the process of scattering sensors,a trajectory model was also proposed.Integrating node scattering manipulation with trajectory model,the node deployment in wireless sensor network was thoroughly renovated,that is,this scheme can scatter sensors.In practice,the scheme was operable compared with the previous achievements.The simulation results demonstrate the superiority and feasibility of the scheme,and also show that the energy consumption for sensors relocation is reduced.展开更多
The fact of proportional population growth in many countries drags the attention of researchers in the field of crowd dynamics to the need for developing reliable models to predict the behavior of human crowds in emer...The fact of proportional population growth in many countries drags the attention of researchers in the field of crowd dynamics to the need for developing reliable models to predict the behavior of human crowds in emergency situations such as evacuation processes. Computer based models that simulate human crowd dynamics prove to offer the optimum way to predict the crowd realistic behavior especially in emergency situations. This paper presents a vital extension of my previous work in which an individual-based model to simulate the behavior of human crowd was developed using the artificial potential fields to describe the interaction forces between each crowd member and the environment on one side and amongst the crowd members on the other side to add realistic flavor to the predicted crowd behavior. In this paper, the successive multi-goals (SMG) method, which is a new method to represent the environment in which the crowd moves, is developed. Rather than using the traditional static potential field, the successive multi-goals method uses a dynamic potential field which is vital to solve the reactive problem that is considered as a drawback of the model when simulating the human crowd behavior during evacuation of buildings whose structures are complex such as bottlenecks and narrow corridors. Numerical results that match the real behavior of human individuals in emergency situations prove the efficiency of the new method to solve the problem on an individual basis as well as its applicability.展开更多
Using the Splitting Hopkinson Pressure Bar (SHPB) experimental system, investigations were made into the dynamic mechanical performances of underground soft rocks. The experiments proved that the measured stress-str...Using the Splitting Hopkinson Pressure Bar (SHPB) experimental system, investigations were made into the dynamic mechanical performances of underground soft rocks. The experiments proved that the measured stress-strain curves display the characteristics of plastic deformation. By making use of a revised overstress constitutive formula for the stress model and by taking into account that the strain rate and strain are a function of I - E(t)/Eo, a revised overstress constitutive formula for the stress model was simplified by applying dimensional analysis and consequently, a simplified overstress formula was obtained for the stress model. Then, by taking into consideration the effects of damage under a dynamic load on the dynamic loading strength of the rock, the continuous damage theory and the statistical strength theory were introduced into the development of the simplified overstress constitutive formula for the stress model. Hence, a damage-based constitutive formula for an overstress model, which can be appropriately applied to the analysis of full dynamic stress-strain curves, was developed. By using the simplified damage-based constitutive formula for an overstress model, the actually measured curves are fitted, indicating that the fitting curves and those actually measured are in good agreement.展开更多
This paper starts from other scholars' studies of multimodality and multimodal discourse and discusses PPT--PowerPoint, as a pragmatic and effective means in teaching English to non-English major students. By using m...This paper starts from other scholars' studies of multimodality and multimodal discourse and discusses PPT--PowerPoint, as a pragmatic and effective means in teaching English to non-English major students. By using multiple modalities of language, pictures, sound; and videos together with the facilities of slide-projector and computer, the multimodal background provides top teaching auxiliary for teachers employing PPT to achieve most desirable effects in real class. This paper discusses the feasibility and effectiveness of PPT as teaching materials and PPT-based class construction in order to show examples to other English teachers how to conduct English teaching and promote students to take more interests in English learning. The writer gets to the conclusion that PPT, as a multimodal measure in teaching, can help the students to learn English more effectively and teachers to achieve better quality in lectures.展开更多
Under the target of the sustainable development,optimization of forestry industrial structure contains rationalization and advancement of forestry industrial structure in the traditional sense,as well as ecologicaliza...Under the target of the sustainable development,optimization of forestry industrial structure contains rationalization and advancement of forestry industrial structure in the traditional sense,as well as ecologicalization of forestry industrial structure.The connotation of optimization of forestry industrial structure is analyzed at first,and then the paper chooses the typical evaluation indexes from the three sides of rationalization,advancement and ecologicalization to evaluate the current situation of the regional forestry industrial structure.With the aid of the theory of fuzzy mathematics and information entropy,the paper establishes a fuzzy evaluation model which is based on information entropy for optimization of forestry industrial structure,and the evaluation model is applied in the study for the current situation of forestry industrial structure from 2000 to 2006 in Hubei province.The results show that the grade of forestry industrial structure is bad basically during the research,of which the overall level of forestry industrial structure of Hubei province is poor,the degree of utilizing forest resource is lower,and ecological environment in the forest region has been damaged to some extent.On this basis,the author presents the countermeasure to promote the optimization of forestry industrial structure.展开更多
Today, digital signal processing based on new microprocessor technology allows for successful machine protection and is acceptably cost-effective. Furthermore, by means of vibration-diagnostics monitoring of machines ...Today, digital signal processing based on new microprocessor technology allows for successful machine protection and is acceptably cost-effective. Furthermore, by means of vibration-diagnostics monitoring of machines assisted by analytical methods it is possible to monitor and quantify dynamic parameters of a machine. By means of the analysis of dynamic behavior of rotor, it is possible to diagnose and solve the defects relating to rotor and other parts of machine. Recently, vibrations analysis and monitoring have become the most widespread method of machine diagnostics. Detection, identification and elimination of problems related to machine work can be simplified by modeling some dynamics solutions. The paper presents a mathematical model of elastic rotor with concentrated weight designed for the purpose of detecting defects with the help of vibrations measured by sensors based in bearings. Experimental results from test tables of the world's leading company, Bentley Nevada Co. USA, were used as the basis for development of this model. Accordingly, mathematical model for most of the cases was based on radial oscillation of rotor while torsion oscillations were used as the basis in some cases. Torsion vibrations cannot be detected without special sensors even at their highest magnitudes. Reliability of this model and accuracy of vibrodiagnostic analysis has been experimentally confirmed when applied on machines in operation.展开更多
This paper aims to develop a novel knowledge management framework for improving the system of pro-safety attitudes among young worker population in Poland. This is done through an efficient use of existing sources of ...This paper aims to develop a novel knowledge management framework for improving the system of pro-safety attitudes among young worker population in Poland. This is done through an efficient use of existing sources of explicit and tacit knowledge in the field of vocational occupational safety and health (OSH) training. This project identifies three specific research steps for the development of the knowledge management framework of the information technology-based approach for improving occupational safety training of young workers, including: (1) the development of the conceptual model of the flow of explicit knowledge of OSH; (2) evaluation of the effectiveness of formal and explicit knowledge sources for OSH and training methods using these sources in the context of attitudes towards health and safety at work; and (3) verification of the proposed model of vocational training with the use of combined explicit and hidden knowledge. The proposed framework includes consideration of the effectiveness of the formal and informal sources of safety knowledge. A mapping from the formal sources of explicit knowledge about the occupational safety to expected attitudes (hidden knowledge) towards OSH outcomes, including emotional, cognitive, and behavioral aspects has been used. The above framework should help to improve the system of vocational training for young workers in Poland.展开更多
The construction of China-Mongolia-Russia high-speed railways is a strategic move to promote transportation infrastructure inter-connectivity between these countries, which will accelerate the implementation of the Ch...The construction of China-Mongolia-Russia high-speed railways is a strategic move to promote transportation infrastructure inter-connectivity between these countries, which will accelerate the implementation of the China-Mongolia-Russia Economic Corridor. However, well-planned China-Mongolia-Russia high-speed railways demand accurately identifying construction risks, scientifically evaluating risk levels, and mapping the spatial distribution of these risks. Therefore, this study established the integrated risk evaluation model(IREM) to scientifically evaluate the economic, social, and ecological risks of China-Mongolia-Russia high-speed railway construction and determine their magnitude and spatial distribution pattern. Based on this analysis, we propose designs for the east and west China-Mongolia-Russia high-speed railways and policy suggestions to mitigate construction risks. Suggestions include developing innovative cooperation of the "high-speed railway for resources and market", strengthening communication and technology dissemination, and applying innovative engineering techniques and setting buffers; establishing collaborative prevention and control systems to mitigate the three major ecological risks in the China, Mongolia, and Russia trans-border areas; and promoting economic integration by improving strategic coordination. In summary, this study provides scientific support for designing the China-Mongolia-Russia high-speed railways minimizing construction risks.展开更多
Ecological compensation is becoming one of key and multidiscipline issues in the field of resources and environmental management. Considering the change relation between gross domestic product (GDP) and ecological cap...Ecological compensation is becoming one of key and multidiscipline issues in the field of resources and environmental management. Considering the change relation between gross domestic product (GDP) and ecological capital (EC) based on remote sensing estimation, we construct a new quantitative estimate model for ecological compensation, using county as study unit, and determine standard value so as to evaluate ecological compensation from 2001 to 2004 in Zhejiang Province, China. Spatial differences of the ecological compensation were significant among all the counties or districts. This model fills up the gap in the field of quantitative evaluation of regional ecological compensation and provides a feasible way to reconcile the conflicts among benefits in the economic, social, and ecological sectors.展开更多
A dynalnic model of skeletal muscle is developed to describe its activation kinetics and contraction dynamics based on the collective working mechanism of myosin II motors with a statistical mechanics method. Accordin...A dynalnic model of skeletal muscle is developed to describe its activation kinetics and contraction dynamics based on the collective working mechanism of myosin II motors with a statistical mechanics method. According to the structure of sar- comeres arranged in series and in parallel, the mechanical properties of skeletal muscle are studied. This model reveals the re- lations between action potential and muscle characteristics. It is shown that calcium concentration in sarcoplasmic (SP) in- creases linearly with the increasing stimulation frequency and gradually reaches saturation. Active force and contraction veloc- ity follow the trend of calcium concentration and reach a peak value at the maximum stimulation frequency. Contraction ve- locity is inversely proportional to the load while the contraction power increases to maximum and then reduces to zero with the increasing load. These properties are consistent with published physiological experimental results of skeletal muscle.展开更多
To solve the problems encountered in practical processes of magneto-optical sensing, the infinitesimal distributed-parameter model and finite-element accumulation of different dielectric properties of micromaterials w...To solve the problems encountered in practical processes of magneto-optical sensing, the infinitesimal distributed-parameter model and finite-element accumulation of different dielectric properties of micromaterials were used to describe the evolution of light polarization states, instead of the previously commonly used method of lumped-parameter simulation, thus essentially explaining the mechanism of sensing, magneto-optical effects, and related factors, and achieving multiphysics coupling using the COMSOL finite-element analysis method. Considering the cases of the Faraday effect without and with line birefringence, the magneto-optical effect and output characteristics of an infinitesimal magneto-optical sensor were simulated and studied. The results verified the effectiveness of the infinitesimal sensor model. Because the magnetic field, stress, and temperature changes alter the dielectric properties of magneto-optical materials, the finite-element accumulation method lays a good foundation for research on theoretical analysis and performance of magneto-optical sensors affected by factors such as the magnetic field, temperature, and stress.展开更多
基金Project(E2012203177)supported by the Natural Science Foundation of Hebei Province,ChinaProject(2011BAF15B01)supported by the National Science and Technology Support Plan of China+1 种基金Project(E2006001038)supported by Great Natural Science Foundation of Hebei Province,ChinaProject(NECSR-201202)supported by Open Project Program of National Engineering Research Center for Equipment and Technology of Cold Strip Rolling,China
文摘The dynamic model of cold rolling mill based on strip flatness and thickness integrated control was proposed,containing the following sub-models:the rolling process model,the dynamic model of rolls along axial direction,and the compensation model.Based on the rule of volume flow rate,the dynamic rolling process model was built.The work roll and backup roll were taken as elastic continuous bodies,the effect of shear and moment of inertia were taken into consideration,and then the dynamic model of rolls was built.The two models were coupled together,and the dynamic model of rolling mill was built.In the dynamic model,the thermal expansion of the rolls,the wear of the rolls and other related parameters can not be considered.In order to compensate the dynamic model,the coupled static model of rolls and strip was applied.Then,according to the inner relationship of these models,the dynamic model and the compensation model were coupled,and the dynamic model of rolling mill based on the strip flatness and thickness integrated control was built.The dynamic simulation of the rolling process was made,and the dynamic thickness and the dynamic flatness information were obtained.This model not only provides a theory basis for the virtual rolling,but also provides a platform for the application of advanced control theory.
基金supported by the Research and Innovation Program for College and University Graduate Students in Jiangsu Province (No.CX10B-141Z)the National Natural Science Foundation of China (No. 41071273)
文摘In order to study dynamic laws of surface movements over coal mines due to mining activities,a dynamic prediction model of surface movements was established,based on the theory of support vector machines(SVM) and times-series analysis.An engineering application was used to verify the correctness of the model.Measurements from observation stations were analyzed and processed to obtain equal-time interval surface movement data and subjected to tests of stationary,zero means and normality.Then the data were used to train the SVM model.A time series model was established to predict mining subsidence by rational choices of embedding dimensions and SVM parameters.MAPE and WIA were used as indicators to evaluate the accuracy of the model and for generalization performance.In the end,the model was used to predict future surface movements.Data from observation stations in Huaibei coal mining area were used as an example.The results show that the maximum absolute error of subsidence is 9 mm,the maximum relative error 1.5%,the maximum absolute error of displacement 7 mm and the maximum relative error 1.8%.The accuracy and reliability of the model meet the requirements of on-site engineering.The results of the study provide a new approach to investigate the dynamics of surface movements.
基金Project(2007AA01Z224) supported by National High-Tech Research and Development Program of China
文摘To deploy sensor nodes over the area of interest,a scheme,named node scattering manipulation,was proposed.It adopted the following method:during node scattering,the initial states of every node,including the velocity and direction,were manipulated so that it would land in a region with a certain probability;every sensor was relocated in order to improve the coverage and connectivity.Simultaneously,to easily analyze the process of scattering sensors,a trajectory model was also proposed.Integrating node scattering manipulation with trajectory model,the node deployment in wireless sensor network was thoroughly renovated,that is,this scheme can scatter sensors.In practice,the scheme was operable compared with the previous achievements.The simulation results demonstrate the superiority and feasibility of the scheme,and also show that the energy consumption for sensors relocation is reduced.
文摘The fact of proportional population growth in many countries drags the attention of researchers in the field of crowd dynamics to the need for developing reliable models to predict the behavior of human crowds in emergency situations such as evacuation processes. Computer based models that simulate human crowd dynamics prove to offer the optimum way to predict the crowd realistic behavior especially in emergency situations. This paper presents a vital extension of my previous work in which an individual-based model to simulate the behavior of human crowd was developed using the artificial potential fields to describe the interaction forces between each crowd member and the environment on one side and amongst the crowd members on the other side to add realistic flavor to the predicted crowd behavior. In this paper, the successive multi-goals (SMG) method, which is a new method to represent the environment in which the crowd moves, is developed. Rather than using the traditional static potential field, the successive multi-goals method uses a dynamic potential field which is vital to solve the reactive problem that is considered as a drawback of the model when simulating the human crowd behavior during evacuation of buildings whose structures are complex such as bottlenecks and narrow corridors. Numerical results that match the real behavior of human individuals in emergency situations prove the efficiency of the new method to solve the problem on an individual basis as well as its applicability.
基金supported by funds from the National Natural Science Foundation of China (Nos. 51374013, 51174005 and 51134012)the Huo Yingdong Funds for Young Teachers to Conduct Researches on Basic Sciences (No. 121050)+1 种基金the academic research activities subsidies for academic and technical leaders and backup candidate in Anhui provincethe funds for the Doctoral Program of Higher Education (No. 20133415110006)
文摘Using the Splitting Hopkinson Pressure Bar (SHPB) experimental system, investigations were made into the dynamic mechanical performances of underground soft rocks. The experiments proved that the measured stress-strain curves display the characteristics of plastic deformation. By making use of a revised overstress constitutive formula for the stress model and by taking into account that the strain rate and strain are a function of I - E(t)/Eo, a revised overstress constitutive formula for the stress model was simplified by applying dimensional analysis and consequently, a simplified overstress formula was obtained for the stress model. Then, by taking into consideration the effects of damage under a dynamic load on the dynamic loading strength of the rock, the continuous damage theory and the statistical strength theory were introduced into the development of the simplified overstress constitutive formula for the stress model. Hence, a damage-based constitutive formula for an overstress model, which can be appropriately applied to the analysis of full dynamic stress-strain curves, was developed. By using the simplified damage-based constitutive formula for an overstress model, the actually measured curves are fitted, indicating that the fitting curves and those actually measured are in good agreement.
文摘This paper starts from other scholars' studies of multimodality and multimodal discourse and discusses PPT--PowerPoint, as a pragmatic and effective means in teaching English to non-English major students. By using multiple modalities of language, pictures, sound; and videos together with the facilities of slide-projector and computer, the multimodal background provides top teaching auxiliary for teachers employing PPT to achieve most desirable effects in real class. This paper discusses the feasibility and effectiveness of PPT as teaching materials and PPT-based class construction in order to show examples to other English teachers how to conduct English teaching and promote students to take more interests in English learning. The writer gets to the conclusion that PPT, as a multimodal measure in teaching, can help the students to learn English more effectively and teachers to achieve better quality in lectures.
基金supported by National Social Sciences Fund of China (Grant No 09XSH018)
文摘Under the target of the sustainable development,optimization of forestry industrial structure contains rationalization and advancement of forestry industrial structure in the traditional sense,as well as ecologicalization of forestry industrial structure.The connotation of optimization of forestry industrial structure is analyzed at first,and then the paper chooses the typical evaluation indexes from the three sides of rationalization,advancement and ecologicalization to evaluate the current situation of the regional forestry industrial structure.With the aid of the theory of fuzzy mathematics and information entropy,the paper establishes a fuzzy evaluation model which is based on information entropy for optimization of forestry industrial structure,and the evaluation model is applied in the study for the current situation of forestry industrial structure from 2000 to 2006 in Hubei province.The results show that the grade of forestry industrial structure is bad basically during the research,of which the overall level of forestry industrial structure of Hubei province is poor,the degree of utilizing forest resource is lower,and ecological environment in the forest region has been damaged to some extent.On this basis,the author presents the countermeasure to promote the optimization of forestry industrial structure.
文摘Today, digital signal processing based on new microprocessor technology allows for successful machine protection and is acceptably cost-effective. Furthermore, by means of vibration-diagnostics monitoring of machines assisted by analytical methods it is possible to monitor and quantify dynamic parameters of a machine. By means of the analysis of dynamic behavior of rotor, it is possible to diagnose and solve the defects relating to rotor and other parts of machine. Recently, vibrations analysis and monitoring have become the most widespread method of machine diagnostics. Detection, identification and elimination of problems related to machine work can be simplified by modeling some dynamics solutions. The paper presents a mathematical model of elastic rotor with concentrated weight designed for the purpose of detecting defects with the help of vibrations measured by sensors based in bearings. Experimental results from test tables of the world's leading company, Bentley Nevada Co. USA, were used as the basis for development of this model. Accordingly, mathematical model for most of the cases was based on radial oscillation of rotor while torsion oscillations were used as the basis in some cases. Torsion vibrations cannot be detected without special sensors even at their highest magnitudes. Reliability of this model and accuracy of vibrodiagnostic analysis has been experimentally confirmed when applied on machines in operation.
文摘This paper aims to develop a novel knowledge management framework for improving the system of pro-safety attitudes among young worker population in Poland. This is done through an efficient use of existing sources of explicit and tacit knowledge in the field of vocational occupational safety and health (OSH) training. This project identifies three specific research steps for the development of the knowledge management framework of the information technology-based approach for improving occupational safety training of young workers, including: (1) the development of the conceptual model of the flow of explicit knowledge of OSH; (2) evaluation of the effectiveness of formal and explicit knowledge sources for OSH and training methods using these sources in the context of attitudes towards health and safety at work; and (3) verification of the proposed model of vocational training with the use of combined explicit and hidden knowledge. The proposed framework includes consideration of the effectiveness of the formal and informal sources of safety knowledge. A mapping from the formal sources of explicit knowledge about the occupational safety to expected attitudes (hidden knowledge) towards OSH outcomes, including emotional, cognitive, and behavioral aspects has been used. The above framework should help to improve the system of vocational training for young workers in Poland.
基金Science and Technology Basic Resources Survey Project of China,No.2017FY101304Major R&D Project of Chinese Academy of Sciences,No.ZDRW-ZS-2016-6-5National Natural Science Foundation of China,No.41701639
文摘The construction of China-Mongolia-Russia high-speed railways is a strategic move to promote transportation infrastructure inter-connectivity between these countries, which will accelerate the implementation of the China-Mongolia-Russia Economic Corridor. However, well-planned China-Mongolia-Russia high-speed railways demand accurately identifying construction risks, scientifically evaluating risk levels, and mapping the spatial distribution of these risks. Therefore, this study established the integrated risk evaluation model(IREM) to scientifically evaluate the economic, social, and ecological risks of China-Mongolia-Russia high-speed railway construction and determine their magnitude and spatial distribution pattern. Based on this analysis, we propose designs for the east and west China-Mongolia-Russia high-speed railways and policy suggestions to mitigate construction risks. Suggestions include developing innovative cooperation of the "high-speed railway for resources and market", strengthening communication and technology dissemination, and applying innovative engineering techniques and setting buffers; establishing collaborative prevention and control systems to mitigate the three major ecological risks in the China, Mongolia, and Russia trans-border areas; and promoting economic integration by improving strategic coordination. In summary, this study provides scientific support for designing the China-Mongolia-Russia high-speed railways minimizing construction risks.
基金Project (No. 2006AA120101) supported by the Hi-Tech Research and Development Program (863) of China
文摘Ecological compensation is becoming one of key and multidiscipline issues in the field of resources and environmental management. Considering the change relation between gross domestic product (GDP) and ecological capital (EC) based on remote sensing estimation, we construct a new quantitative estimate model for ecological compensation, using county as study unit, and determine standard value so as to evaluate ecological compensation from 2001 to 2004 in Zhejiang Province, China. Spatial differences of the ecological compensation were significant among all the counties or districts. This model fills up the gap in the field of quantitative evaluation of regional ecological compensation and provides a feasible way to reconcile the conflicts among benefits in the economic, social, and ecological sectors.
基金supported by the National Natural Science Foundation of China (Grant No. 61075101/60643002)the Research Fund of State Key Lab of MSV,China (Grant No. MSV-2010-1)+1 种基金the Science and Technology Intercrossingthe Medical and Technology Intercrossing Research Foundation of Shanghai Jiao Tong University (Grant No. YG2010ZD101)
文摘A dynalnic model of skeletal muscle is developed to describe its activation kinetics and contraction dynamics based on the collective working mechanism of myosin II motors with a statistical mechanics method. According to the structure of sar- comeres arranged in series and in parallel, the mechanical properties of skeletal muscle are studied. This model reveals the re- lations between action potential and muscle characteristics. It is shown that calcium concentration in sarcoplasmic (SP) in- creases linearly with the increasing stimulation frequency and gradually reaches saturation. Active force and contraction veloc- ity follow the trend of calcium concentration and reach a peak value at the maximum stimulation frequency. Contraction ve- locity is inversely proportional to the load while the contraction power increases to maximum and then reduces to zero with the increasing load. These properties are consistent with published physiological experimental results of skeletal muscle.
基金supported by the National Natural Science Foundation of China(Grant No.51277066)
文摘To solve the problems encountered in practical processes of magneto-optical sensing, the infinitesimal distributed-parameter model and finite-element accumulation of different dielectric properties of micromaterials were used to describe the evolution of light polarization states, instead of the previously commonly used method of lumped-parameter simulation, thus essentially explaining the mechanism of sensing, magneto-optical effects, and related factors, and achieving multiphysics coupling using the COMSOL finite-element analysis method. Considering the cases of the Faraday effect without and with line birefringence, the magneto-optical effect and output characteristics of an infinitesimal magneto-optical sensor were simulated and studied. The results verified the effectiveness of the infinitesimal sensor model. Because the magnetic field, stress, and temperature changes alter the dielectric properties of magneto-optical materials, the finite-element accumulation method lays a good foundation for research on theoretical analysis and performance of magneto-optical sensors affected by factors such as the magnetic field, temperature, and stress.