The movement pattern of ellipsoidal nanoparticles confined between copper surfaces was examined using a theoretical model and molecular dynamics simulation.Initially,we developed a theoretical model of movement patter...The movement pattern of ellipsoidal nanoparticles confined between copper surfaces was examined using a theoretical model and molecular dynamics simulation.Initially,we developed a theoretical model of movement patterns for hard ellipsoidal nanoparticles.Subsequently,the simulation indicated that there are critical values for increasing the axial ratio,driving velocity of the contact surface,and lowering normal loads(i.e.,0.83,15 m/s,and 100 nN under the respective conditions),which in turn change the movement pattern of nanoparticles from sliding to rolling.Based on the comparison between the ratio of arm of force(e/h)and coefficient of friction(μ),the theoretical model was in good agreement with the simulations and accurately predicted the movement pattern of ellipsoidal nanoparticles.The sliding of the ellipsoidal nanoparticles led to severe surface damage.However,rolling separated the contact surfaces and thereby reduced friction and wear.展开更多
As a typical rhythmic movement, human being＇s rhythmic gait movement can be generated by a central pattern generator （CPG） located in a spinal cord by self- oscillation. Some kinds of gait movements are caused by g...As a typical rhythmic movement, human being＇s rhythmic gait movement can be generated by a central pattern generator （CPG） located in a spinal cord by self- oscillation. Some kinds of gait movements are caused by gait frequency and amplitude variances. As an important property of human being＇s motion vision, the attention selection mechanism plays a vital part in the regulation of gait movement. In this paper, the CPG model is amended under the condition of attention selection on the theoretical basis of Matsuoka neural oscillators. Regulation of attention selection signal for the CPG model parameters and structure is studied, which consequentially causes the frequency and amplitude changes of gait movement output. Further, the control strategy of the CPG model gait movement under the condition of attention selection is discussed, showing that the attention selection model can regulate the output model of CPG gait movement in three different ways. The realization of regulation on the gait movement frequency and amplitude shows a variety of regulation on the CPG gait movement made by attention selection and enriches the controllability of CPG gait movement, which demonstrates potential influence in engineering applications.展开更多
Population movement is an important phenomenon in China in recent years. Its mechanism is: (1) thrust of more people and less land in the eastern region of China; (2) attraction of dual economy in the western region o...Population movement is an important phenomenon in China in recent years. Its mechanism is: (1) thrust of more people and less land in the eastern region of China; (2) attraction of dual economy in the western region of China; (3) national policy on preferential wages and grains for the western region. Population movement has an important effect on the change of regional division pattern in China: by the medium of the moving people, there forms another regional division pattern, i.e. rural industry system based on rural town industry; (2) there forms another profit mechanism compensated from the western region to the eastern region. It not only wins more profit in the eastern region, but also changes dual economy in the western region. Therefore, We should make choice of a comprehensible and encouraging attitude on population movement; a special government organization for general survey of the moving people should be set up at once.展开更多
In this paper,multi_quadric equations interpolation is used to establish a widely covered and valuable speed field model,with which the crustal movement image is obtained.
Understanding how signal properties are optimized for the reliable transmission of information requires accurate descriptionof the signal in time and space. For movement-based signals where movement is restricted to a...Understanding how signal properties are optimized for the reliable transmission of information requires accurate descriptionof the signal in time and space. For movement-based signals where movement is restricted to a single plane, measurementsfrom a single viewpoint can be used to consider a range of viewing positions based on simple geometric calculations.However, considerations of signal properties from a range of viewing positions for movements extending into three-dimensions(3D) are more problematic. We present here a new framework that overcomes this limitation, and enables us to quantify the extentto which movement-based signals are view-specific. To illustrate its application, a Jacky lizard tail flick signal was filmed withsynchronized cameras and the position of the tail tip digitized for both recordings. Camera alignment enabled the construction ofa 3D display action pattern profile. We analyzed the profile directly and used it to create a detailed 3D animation. In the virtualenvironment, we were able to film the same signal from multiple viewing positions and using a computational motion analysisalgorithm (gradient detector model) to measure local image velocity in order to predict view dependent differences in signalproperties. This approach will enable consideration of a range of questions concerning movement-based signal design and evolutionthat were previously out of reach [Current Zoology 56 (3): 327-336, 2010].展开更多
Seismic gap method is one of the effective earthquake prediction methods using seismicity patterns. However, this method has some limitations and uncertainty when using it singly in predicting earthquakes. This paper ...Seismic gap method is one of the effective earthquake prediction methods using seismicity patterns. However, this method has some limitations and uncertainty when using it singly in predicting earthquakes. This paper puts forward the prediction method using the dynamic seismicity pattern with dynamic implications. This method considers the formation and evolution of the seismic gap on the basis of plate movement and structural characteristics. Through analysis of 26 cases of earthquakes of MS≥5.0 occurring in East China and South China, this paper obtains the relationship between the main shock with seismic gap and active fault's location, as well as the relationship between the seismic gap and location and strike of active faults. Meanwhile, this paper provides a dynamic explanation of the differences in the formation and evolution patterns of the seismic gap between the two regions, thus providing the physical basis for and reducing the uncertainty of predicting earthquakes using the seismic gap method.展开更多
基金The authors acknowledge the financial support from the National Natural Science Fundation of China(NSFC)(51905433)the National Key R&D Program of China(No.2018YFB0703800)the Fundamental Research Funds for the Central Universities(No.3102019TS0405).
文摘The movement pattern of ellipsoidal nanoparticles confined between copper surfaces was examined using a theoretical model and molecular dynamics simulation.Initially,we developed a theoretical model of movement patterns for hard ellipsoidal nanoparticles.Subsequently,the simulation indicated that there are critical values for increasing the axial ratio,driving velocity of the contact surface,and lowering normal loads(i.e.,0.83,15 m/s,and 100 nN under the respective conditions),which in turn change the movement pattern of nanoparticles from sliding to rolling.Based on the comparison between the ratio of arm of force(e/h)and coefficient of friction(μ),the theoretical model was in good agreement with the simulations and accurately predicted the movement pattern of ellipsoidal nanoparticles.The sliding of the ellipsoidal nanoparticles led to severe surface damage.However,rolling separated the contact surfaces and thereby reduced friction and wear.
基金supported by the National Natural Science Foundation of China(Nos.11232005 and11472104)the Doctoral Fund of Ministry of Education of China(No.20120074110020)
文摘As a typical rhythmic movement, human being＇s rhythmic gait movement can be generated by a central pattern generator （CPG） located in a spinal cord by self- oscillation. Some kinds of gait movements are caused by gait frequency and amplitude variances. As an important property of human being＇s motion vision, the attention selection mechanism plays a vital part in the regulation of gait movement. In this paper, the CPG model is amended under the condition of attention selection on the theoretical basis of Matsuoka neural oscillators. Regulation of attention selection signal for the CPG model parameters and structure is studied, which consequentially causes the frequency and amplitude changes of gait movement output. Further, the control strategy of the CPG model gait movement under the condition of attention selection is discussed, showing that the attention selection model can regulate the output model of CPG gait movement in three different ways. The realization of regulation on the gait movement frequency and amplitude shows a variety of regulation on the CPG gait movement made by attention selection and enriches the controllability of CPG gait movement, which demonstrates potential influence in engineering applications.
文摘Population movement is an important phenomenon in China in recent years. Its mechanism is: (1) thrust of more people and less land in the eastern region of China; (2) attraction of dual economy in the western region of China; (3) national policy on preferential wages and grains for the western region. Population movement has an important effect on the change of regional division pattern in China: by the medium of the moving people, there forms another regional division pattern, i.e. rural industry system based on rural town industry; (2) there forms another profit mechanism compensated from the western region to the eastern region. It not only wins more profit in the eastern region, but also changes dual economy in the western region. Therefore, We should make choice of a comprehensible and encouraging attitude on population movement; a special government organization for general survey of the moving people should be set up at once.
文摘In this paper,multi_quadric equations interpolation is used to establish a widely covered and valuable speed field model,with which the crustal movement image is obtained.
基金National Natural Science Foundation of China （51274205）, the Doctoral Program Foundation of Ministry of Education the New Teacher Project （20070290022） and the Open Project of China University of Mining and Technology Resources and Mine Safety State Key Laboratory （S KLCRSM 10KFB 13）.
文摘Understanding how signal properties are optimized for the reliable transmission of information requires accurate descriptionof the signal in time and space. For movement-based signals where movement is restricted to a single plane, measurementsfrom a single viewpoint can be used to consider a range of viewing positions based on simple geometric calculations.However, considerations of signal properties from a range of viewing positions for movements extending into three-dimensions(3D) are more problematic. We present here a new framework that overcomes this limitation, and enables us to quantify the extentto which movement-based signals are view-specific. To illustrate its application, a Jacky lizard tail flick signal was filmed withsynchronized cameras and the position of the tail tip digitized for both recordings. Camera alignment enabled the construction ofa 3D display action pattern profile. We analyzed the profile directly and used it to create a detailed 3D animation. In the virtualenvironment, we were able to film the same signal from multiple viewing positions and using a computational motion analysisalgorithm (gradient detector model) to measure local image velocity in order to predict view dependent differences in signalproperties. This approach will enable consideration of a range of questions concerning movement-based signal design and evolutionthat were previously out of reach [Current Zoology 56 (3): 327-336, 2010].
基金supported by the National Science and Technology Program of China Earthquake Administration (No. 2006BAC01B02-01-05)Anhui Provincial Science and Technique Foundation (No. 08010302204)Joint Earthquake Science Fundation (A08077)
文摘Seismic gap method is one of the effective earthquake prediction methods using seismicity patterns. However, this method has some limitations and uncertainty when using it singly in predicting earthquakes. This paper puts forward the prediction method using the dynamic seismicity pattern with dynamic implications. This method considers the formation and evolution of the seismic gap on the basis of plate movement and structural characteristics. Through analysis of 26 cases of earthquakes of MS≥5.0 occurring in East China and South China, this paper obtains the relationship between the main shock with seismic gap and active fault's location, as well as the relationship between the seismic gap and location and strike of active faults. Meanwhile, this paper provides a dynamic explanation of the differences in the formation and evolution patterns of the seismic gap between the two regions, thus providing the physical basis for and reducing the uncertainty of predicting earthquakes using the seismic gap method.
