The 3D shape of the human body is useful for applications in fitness, games and apparel. Accurate body scanners, howev- er, are expensive, limiting the availability of 3D body models. In this paper, we focus on the hu...The 3D shape of the human body is useful for applications in fitness, games and apparel. Accurate body scanners, howev- er, are expensive, limiting the availability of 3D body models. In this paper, we focus on the human body 3D modeling using one Kinect sensor modeling method. To get the human body model fast, three steps in rapid modeling of the human body are carried out. Firstly, according to anthropometric parameters, the standard model is parameterized; Secondly, the Kinect depth image of the human body model is gotten through, then, by using the PCL library the point cloud data is processed and matched, and the human body model is optimized; Finally, the realistic human body model is obtained with the rapid integration of the standard model and PCL library.展开更多
Landmarks on human body models are of great significance for applications such as digital anthropometry and clothing design.The diversity of pose and shape of human body models and the semantic gap make landmarking a ...Landmarks on human body models are of great significance for applications such as digital anthropometry and clothing design.The diversity of pose and shape of human body models and the semantic gap make landmarking a challenging problem.Inthis paper,a learning-based method is proposed to locate landmarks on human body models by analyzing the relationship between geometric descriptors and semantic labels of landmarks.A shape alignmentalgorithm is proposed to align human body models to break symmetric ambiguity.A symmetry-awaredescriptor is proposed based on the structure of the human body models,which is robust to both pose and shape variations in human body models.AnAdaBoost regression algorithm is adopted to establish the correspondence between several descriptors and semantic labels of the landmarks.Quantitative and qualitative analyses and comparisons show that the proposed method can obtain more accurate landmarks and distinguish symmetrical landmarks semantically.Additionally,a dataset of landmarked human body models is also provided,containing 271 human body models collected from current human body datasets;each model has 17 landmarks labeled manually.展开更多
After summarizing the current situation of the research on human body modeling, a new dynamic model containing 5 equivalent masses has been proposed and the corresponding dynamic equations has been deduced too. By usi...After summarizing the current situation of the research on human body modeling, a new dynamic model containing 5 equivalent masses has been proposed and the corresponding dynamic equations has been deduced too. By using this new model, more detailed information about the situation of the human body under impact and vibration can be obtained. The new model solves the problem that transmission functions of forces inside the human body can't be deduced by using 3-equivalent-mass model. It will find its usage in many applications.展开更多
In the study,a quantum resonant cavity model based on wave-particle duality was proposed for the explanation of the dynamic processes of essence,vigor,and spirit in the human body in traditional Chinese medicine(TCM)....In the study,a quantum resonant cavity model based on wave-particle duality was proposed for the explanation of the dynamic processes of essence,vigor,and spirit in the human body in traditional Chinese medicine(TCM).It is assumed that there is a macro human order parameter(wave function),and its dynamics are governed by a macro potential field reflecting influences from heaven,earth,and society,and satisfy the generalized Schrodinger equation.This proposed model was applied in the study to interpret basic concepts of human body in TCM,with an aim to unfold the TCM development in the future.展开更多
Modeling of the human body is a basic problem in computer animation of the humanbody. This paper presents a method in which the combination of polyhedra is used to establish aninitial rough design of the human body an...Modeling of the human body is a basic problem in computer animation of the humanbody. This paper presents a method in which the combination of polyhedra is used to establish aninitial rough design of the human body and subdivision of polyhedra to approximate the curvesurface of the real human body. In addition, the dynamic characteristics are taken intoconsideration of the human body, thus providing a fine basis for the establishment of the bumanbody animation.展开更多
Two-way feedback of human body was published in 1992. The sensation of two-way feedback of body is a special system of human reaction, which maintains and regulates symmetry and balance of human body. The human two-wa...Two-way feedback of human body was published in 1992. The sensation of two-way feedback of body is a special system of human reaction, which maintains and regulates symmetry and balance of human body. The human two-way feedback reacts to human health. For human overall health and delay decrepitude, it is necessary to pay attention to the stimulations (passive acceptance and initiative interventions) and relevant influences in human body and the stimulative effect. In this paper, the experimental research of stimulation and an example of two-way feedback in human body are given. And lay a foundation of prevention, medical treatment and hygiene of human overall health.展开更多
In this paper we propose a novel method for building animation model of realhuman body from surface scanned data. The human model is represented by a triangular mesh anddescribed as a layered geometric model. The mode...In this paper we propose a novel method for building animation model of realhuman body from surface scanned data. The human model is represented by a triangular mesh anddescribed as a layered geometric model. The model consists of two layers: the control skeletongenerating body animation from motion capture data, and the simplified surface model providing anefficient representation of the skin surface shape. The skeleton is generated automatically fromsurface scanned data using the feature extraction, and then a point-to-line mapping is used to mapthe surface model onto the underlying skeleton. The resulting model enables real-time and smoothanimation by manipulation of the skeleton while maintaining the surface detail. Compared withearlier approach, the principal advantages of our approach are the automated generation of bodycontrol skeletons from the scanned data for real-time animation, and the automatic mapping andanimation of the captured human surface shape. The human model constructed in this work can be usedfor applications of ergonomic design, garment CAD, real-time simulating humans in virtual realityenvironment and so on.展开更多
Highly realistic virtual human models are rapidly becoming commonplace incomputer graphics. These models, often represented by complex shape and requiring labor-intensiveprocess, challenge the problem of automatic mod...Highly realistic virtual human models are rapidly becoming commonplace incomputer graphics. These models, often represented by complex shape and requiring labor-intensiveprocess, challenge the problem of automatic modeling. The problem and solutions to automaticmodeling of animatable virtual humans are studied. Methods for capturing the shape of real people,parameterization techniques for modeling static shape (the variety of human body shapes) and dynamicshape (how the body shape changes as it moves) of virtual humans are classified, summarized andcompared. Finally, methods for clothed virtual humans are reviewed.展开更多
Investigation of the vertical vibration characteristics of the seated human body is beneficial for the design and development of vehicle ride comfort.In this study,we first established models of the seated human body ...Investigation of the vertical vibration characteristics of the seated human body is beneficial for the design and development of vehicle ride comfort.In this study,we first established models of the seated human body with two,three and four degrees of freedom(DOF).Then,the vibration characteristics of 30 volunteers were tested under standard conditions with a vibration test rig to obtain data for the apparent mass,driving point mechanical impedance,and seat-to-head transfer function.Based on the experimental data,the parameters of these models are identified and the results show that the four-DOF model can simulate the vertical vibration characteristics of the seated human body more comprehensively.Then,different seated human body models were applied to optimize the damping of shock absorber.The results show that the optimized damping with the four-DOF Chinese seated human body model is 27%more than that with rigid mass and 7%less than that with ISO 5982:2001 seated human body model.展开更多
A novel polysilicon-assisted silicon-controlled rectifier (SCR) is presented and analyzed in this paper, which is fabricated in HHNEC's 0.18μm EEPROM process. The polysilicon-assisted SCRs take advantage of polysi...A novel polysilicon-assisted silicon-controlled rectifier (SCR) is presented and analyzed in this paper, which is fabricated in HHNEC's 0.18μm EEPROM process. The polysilicon-assisted SCRs take advantage of polysilicon layer to help bypass electro-static discharge (E S D) current without occupying extra layout area. TLP current-voltage (I-V) measurement results show that given the same layout areas, robustness performance of polysilicon-assisted SCRs can be improved to 3 times of conventional MLSCR's. Moreover, one-finger such polysilicon-assisted SCRs, which occupy only 947 [3mz layout area, can undergo 7-kV HBM ESD stress. Results further demonstrate that the S-type I-V characteristics of polysilicon-assisted SCRs are adjustable to different operating conditions by changing the device dimensions. Compared with traditional SCRs, this new SCR can bypass more ESD currents and consumes smaller IC area.展开更多
A subsystem impactor test for pedestrian lower limb injury evaluation has been brought in China New Car Assessment Protocol(CNCAP).Concerning large anthropometric differences of the people from different countries,the...A subsystem impactor test for pedestrian lower limb injury evaluation has been brought in China New Car Assessment Protocol(CNCAP).Concerning large anthropometric differences of the people from different countries,the present study aims to establish and validate a finite element lower limb model representing 50th Chinese male size for pedestrian safety research,then compare its biomechanical responses with the general models currently in wide use in the world for pedestrian safety evaluation.Concerning the vehicle-pedestrian impact loading environment,the previously developed lower limb model with three-dimensional muscles was adjusted and validated through the related experiments.Then,the biomechanical responses of the validated model were compared with the Total Human Model for Safety(THUMS)and Advanced Pedestrian Legform Impactor(aPLI)models by combing with four typical vehicles.The results showed that both consistency and significant differences of biomechanical responses existed between the present model and the other two models.The injury measurements of the thigh region of the present model showed extremely large differences with the other two models,while the tibia and Medial Collateral Ligament(MCL)injury measurements show similar values.Thus,it can be concluded that directly using the aPLI or THUMS models for Chinese pedestrian safety evaluation is not robust concerning both kinematic responses and injury measurements.展开更多
A new method of elastic articulated objects (human bodies) modeling was presented based on a new conic curve. The model includes 3D object deformable curves which can represent the deformation of human occluding conto...A new method of elastic articulated objects (human bodies) modeling was presented based on a new conic curve. The model includes 3D object deformable curves which can represent the deformation of human occluding contours. The deformation of human occluding contour can be represented by adjusting only four deformation parameters for each limb. Then, the 3D deformation parameters are determined by corresponding 2D contours from a sequence of stereo images. The algorithm presented in this paper includes deformable conic curve parameters determination and the plane, 3D conic curve lying on, parameter determination.展开更多
Existing mobility models have limitations in their ability to simulate the movement of Wireless Body Area Network(WBAN) since body nodes do not exactly follow either classic mobility models or human contact distribu...Existing mobility models have limitations in their ability to simulate the movement of Wireless Body Area Network(WBAN) since body nodes do not exactly follow either classic mobility models or human contact distributions. In this paper, we propose a new mobility model called Body Gauss–Markov Mobility(BGMM) model,which is oriented specially to WBAN. First, we present the random Gauss-Markov mobility model as the most suitable theoretical basis for developing our new model, as its movement pattern can reveal real human body movements. Next, we examine the transfer of human movement states and derive a simplified mathematical Human Mobility Model(HMM). We then construct the BGMM model by combining the RGMM and HMM models. Finally,we simulate the traces of the new mobility model. We use four direct metrics in our proposed mobility model to evaluate its performance. The simulation results show that the proposed BGMM model performs with respect to the direct mobility metrics and can effectively represent a general WBAN-nodes movement pattern.展开更多
Purpose:Under-foot impact loadings can cause serious lower limb injuries in many activities,such asautomobile collisions and underbody explosions to military vehicles.The present study aims to comparethe biomechanical...Purpose:Under-foot impact loadings can cause serious lower limb injuries in many activities,such asautomobile collisions and underbody explosions to military vehicles.The present study aims to comparethe biomechanical responses of the mainstream vehicle occupant dummies with the human body lowerlimb model and analyze their robustness and applicability for assessing lower limb injury risk in underfoot impact loading environments.Methods:The Hybrid III model,the test device for human occupant restraint(THOR)model,and a hybridhuman body model with the human active lower limb model were adopted for under-foot impactanalysis regarding different impact velocities and initial lower limb postures.Results:The results show that the 2 dummy models have larger peak tibial axial force and highersensitivity to the impact velocities and initial postures than the human lower limb model.In particular,the Hybrid III dummy model presented extremely larger peak tibial axial forces than the human lowerlimb model.In the case of minimal difference in tibial axial force,Hybrid III's tibial axial force(7.5 KN)isstill 312.5%that of human active lower limb's(2.4 KN).Even with closer peak tibial axial force values,thebiomechanical response curve shapes of the THOR model show significant differences from the humanlower limb model.Conclusion:Based on the present results,the Hybrid III dummy cannot be used to evaluate the lowerlimb injury risk in under-foot loading environments.In contrast,potential improvement in ankle biofidelity and related soft tissues of the THOR dummy can be implemented in the future for betterapplicability.展开更多
Virtual human is a digital representation of the geometric and behavioral property of human beings in the virtual environment generated by computer. The research goal of virtual human synthesis is to generate realisti...Virtual human is a digital representation of the geometric and behavioral property of human beings in the virtual environment generated by computer. The research goal of virtual human synthesis is to generate realistic human body models and natural human motion behavior. This paper introduces the development of the related researches on these two topics, and some progresses on example based human modeling and motion synthesis, and their applications in Chinese sign language teaching, computeraided sports training and public safety problem studying. Finally, some hot research topics in virtual human synthesis are presented.展开更多
A mechanism-oriented model is proposed here as a speculative but robust attempt to understand whether there might be any increased risk of electrostatically induced contamination,with relevant consequences from the ep...A mechanism-oriented model is proposed here as a speculative but robust attempt to understand whether there might be any increased risk of electrostatically induced contamination,with relevant consequences from the epidemiological viewpoint.This could also be the case for the COVID-19 spreading because an amount of micro-sized droplet nuclei,often carrying net electric charge,are expected to be electro-dynamically involved in a physical process originated by the natural and unperceivable static electrification of human beings.The effects of the triboelectric charging have long been successfully tested because the phenomenon under examination is also implied in the genesis of the electrostatic discharge(ESD),a demanding key objective in the special context of electromagnetic compatibility(EMC).Therefore,the ultimate purpose of this technical paper is to provide valuable insights into infection control,building on what is already being done for maintaining static-safe environments.The stature of the applied model can be further appreciated because some currently observed climate-dependent and sexlinked different vulnerabilities to COVID-19 are critically examined by unique sound arguments.These ultimately focus attention on ambient relative humidity and worn shoes,the latter differing for typology,size and material,for their integrated control of the inadvertent human aptitude to buildup tribocharges.These would appear as a dreadful prerequisite for charge bearing droplets in the airborne state to be efficiently attracted/repelled according to the described electrostatic mechanism.展开更多
A 3-D impedance method has been introduced to compute the electric currents induced in a human body exposed to extremely low-frequency electromagnetic field. The 3-D impedance method has been deduced from Maxwell equa...A 3-D impedance method has been introduced to compute the electric currents induced in a human body exposed to extremely low-frequency electromagnetic field. The 3-D impedance method has been deduced from Maxwell equations and is put into the computation and simulation effectively to the visible human body model, which has 196×114×626 cells and more than 40 types of tissues. As the result, two representative cases are investigated. One is exposure of the human body to 100 μT (1 000 mG), the limit recommended by the International Commission on Non-Ionizing Radiation Protection for the public and the other one is the exposure of human body to 0.4 laT (4 mG), the level at which a statistical link appears with a doubled risk of development of childhood leukaemia. The distribution of induced current density can be obtained and the maximum of induced current are found to be 16 mA/m^2 and 0.07 mA/m^2.展开更多
The human body model(HBM) stress of a no-connect metal cover is tested to obtain the characteristics of abnormal electrostatic discharge,including current waveforms and peak current under varied stress voltage and d...The human body model(HBM) stress of a no-connect metal cover is tested to obtain the characteristics of abnormal electrostatic discharge,including current waveforms and peak current under varied stress voltage and device failure voltage.A new discharge model called the "sparkover-induced model" is proposed based on the results.Then,failure mechanism analysis and model simulation are performed to prove that the transient peak current caused by a sparkover of low arc impedance will result in the devices' premature damage when the potential difference between the no-connect metal cover and the chip exceeds the threshold voltage of sparkover.展开更多
基金Supported by MOE(Ministry of Education in China)Project of Humanities and Social Sciences(No.13YJC890027)the National Natural Science Foundations of China(No.61003173)+1 种基金the Fundamental Research Funds for the Central Universities(No.2012ZZ0063)the Science and Technology Project of Guangzhou City(No.2012J4100002)
文摘The 3D shape of the human body is useful for applications in fitness, games and apparel. Accurate body scanners, howev- er, are expensive, limiting the availability of 3D body models. In this paper, we focus on the human body 3D modeling using one Kinect sensor modeling method. To get the human body model fast, three steps in rapid modeling of the human body are carried out. Firstly, according to anthropometric parameters, the standard model is parameterized; Secondly, the Kinect depth image of the human body model is gotten through, then, by using the PCL library the point cloud data is processed and matched, and the human body model is optimized; Finally, the realistic human body model is obtained with the rapid integration of the standard model and PCL library.
基金jointly supported by the National Natural Science Foundation of China under Grant Nos.61732015,61932018,and 61472349.
文摘Landmarks on human body models are of great significance for applications such as digital anthropometry and clothing design.The diversity of pose and shape of human body models and the semantic gap make landmarking a challenging problem.Inthis paper,a learning-based method is proposed to locate landmarks on human body models by analyzing the relationship between geometric descriptors and semantic labels of landmarks.A shape alignmentalgorithm is proposed to align human body models to break symmetric ambiguity.A symmetry-awaredescriptor is proposed based on the structure of the human body models,which is robust to both pose and shape variations in human body models.AnAdaBoost regression algorithm is adopted to establish the correspondence between several descriptors and semantic labels of the landmarks.Quantitative and qualitative analyses and comparisons show that the proposed method can obtain more accurate landmarks and distinguish symmetrical landmarks semantically.Additionally,a dataset of landmarked human body models is also provided,containing 271 human body models collected from current human body datasets;each model has 17 landmarks labeled manually.
文摘After summarizing the current situation of the research on human body modeling, a new dynamic model containing 5 equivalent masses has been proposed and the corresponding dynamic equations has been deduced too. By using this new model, more detailed information about the situation of the human body under impact and vibration can be obtained. The new model solves the problem that transmission functions of forces inside the human body can't be deduced by using 3-equivalent-mass model. It will find its usage in many applications.
基金the ENN Institute of Life Science and Technology for their financial support。
文摘In the study,a quantum resonant cavity model based on wave-particle duality was proposed for the explanation of the dynamic processes of essence,vigor,and spirit in the human body in traditional Chinese medicine(TCM).It is assumed that there is a macro human order parameter(wave function),and its dynamics are governed by a macro potential field reflecting influences from heaven,earth,and society,and satisfy the generalized Schrodinger equation.This proposed model was applied in the study to interpret basic concepts of human body in TCM,with an aim to unfold the TCM development in the future.
文摘Modeling of the human body is a basic problem in computer animation of the humanbody. This paper presents a method in which the combination of polyhedra is used to establish aninitial rough design of the human body and subdivision of polyhedra to approximate the curvesurface of the real human body. In addition, the dynamic characteristics are taken intoconsideration of the human body, thus providing a fine basis for the establishment of the bumanbody animation.
文摘Two-way feedback of human body was published in 1992. The sensation of two-way feedback of body is a special system of human reaction, which maintains and regulates symmetry and balance of human body. The human two-way feedback reacts to human health. For human overall health and delay decrepitude, it is necessary to pay attention to the stimulations (passive acceptance and initiative interventions) and relevant influences in human body and the stimulative effect. In this paper, the experimental research of stimulation and an example of two-way feedback in human body are given. And lay a foundation of prevention, medical treatment and hygiene of human overall health.
文摘In this paper we propose a novel method for building animation model of realhuman body from surface scanned data. The human model is represented by a triangular mesh anddescribed as a layered geometric model. The model consists of two layers: the control skeletongenerating body animation from motion capture data, and the simplified surface model providing anefficient representation of the skin surface shape. The skeleton is generated automatically fromsurface scanned data using the feature extraction, and then a point-to-line mapping is used to mapthe surface model onto the underlying skeleton. The resulting model enables real-time and smoothanimation by manipulation of the skeleton while maintaining the surface detail. Compared withearlier approach, the principal advantages of our approach are the automated generation of bodycontrol skeletons from the scanned data for real-time animation, and the automatic mapping andanimation of the captured human surface shape. The human model constructed in this work can be usedfor applications of ergonomic design, garment CAD, real-time simulating humans in virtual realityenvironment and so on.
文摘Highly realistic virtual human models are rapidly becoming commonplace incomputer graphics. These models, often represented by complex shape and requiring labor-intensiveprocess, challenge the problem of automatic modeling. The problem and solutions to automaticmodeling of animatable virtual humans are studied. Methods for capturing the shape of real people,parameterization techniques for modeling static shape (the variety of human body shapes) and dynamicshape (how the body shape changes as it moves) of virtual humans are classified, summarized andcompared. Finally, methods for clothed virtual humans are reviewed.
文摘Investigation of the vertical vibration characteristics of the seated human body is beneficial for the design and development of vehicle ride comfort.In this study,we first established models of the seated human body with two,three and four degrees of freedom(DOF).Then,the vibration characteristics of 30 volunteers were tested under standard conditions with a vibration test rig to obtain data for the apparent mass,driving point mechanical impedance,and seat-to-head transfer function.Based on the experimental data,the parameters of these models are identified and the results show that the four-DOF model can simulate the vertical vibration characteristics of the seated human body more comprehensively.Then,different seated human body models were applied to optimize the damping of shock absorber.The results show that the optimized damping with the four-DOF Chinese seated human body model is 27%more than that with rigid mass and 7%less than that with ISO 5982:2001 seated human body model.
文摘A novel polysilicon-assisted silicon-controlled rectifier (SCR) is presented and analyzed in this paper, which is fabricated in HHNEC's 0.18μm EEPROM process. The polysilicon-assisted SCRs take advantage of polysilicon layer to help bypass electro-static discharge (E S D) current without occupying extra layout area. TLP current-voltage (I-V) measurement results show that given the same layout areas, robustness performance of polysilicon-assisted SCRs can be improved to 3 times of conventional MLSCR's. Moreover, one-finger such polysilicon-assisted SCRs, which occupy only 947 [3mz layout area, can undergo 7-kV HBM ESD stress. Results further demonstrate that the S-type I-V characteristics of polysilicon-assisted SCRs are adjustable to different operating conditions by changing the device dimensions. Compared with traditional SCRs, this new SCR can bypass more ESD currents and consumes smaller IC area.
基金This work is supported by the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(Grant No.51621004)National Natural Science Foundation of China(Grant No.51875187)+1 种基金Hunan Youth Talent Program(Grant No.2020RC3016)Hunan Provincial Natural Science Foundation of China(Grant No.2019JJ40021).
文摘A subsystem impactor test for pedestrian lower limb injury evaluation has been brought in China New Car Assessment Protocol(CNCAP).Concerning large anthropometric differences of the people from different countries,the present study aims to establish and validate a finite element lower limb model representing 50th Chinese male size for pedestrian safety research,then compare its biomechanical responses with the general models currently in wide use in the world for pedestrian safety evaluation.Concerning the vehicle-pedestrian impact loading environment,the previously developed lower limb model with three-dimensional muscles was adjusted and validated through the related experiments.Then,the biomechanical responses of the validated model were compared with the Total Human Model for Safety(THUMS)and Advanced Pedestrian Legform Impactor(aPLI)models by combing with four typical vehicles.The results showed that both consistency and significant differences of biomechanical responses existed between the present model and the other two models.The injury measurements of the thigh region of the present model showed extremely large differences with the other two models,while the tibia and Medial Collateral Ligament(MCL)injury measurements show similar values.Thus,it can be concluded that directly using the aPLI or THUMS models for Chinese pedestrian safety evaluation is not robust concerning both kinematic responses and injury measurements.
基金the Postdoctoral Science Foundation of China(Grant No.20070421018)
文摘A new method of elastic articulated objects (human bodies) modeling was presented based on a new conic curve. The model includes 3D object deformable curves which can represent the deformation of human occluding contours. The deformation of human occluding contour can be represented by adjusting only four deformation parameters for each limb. Then, the 3D deformation parameters are determined by corresponding 2D contours from a sequence of stereo images. The algorithm presented in this paper includes deformable conic curve parameters determination and the plane, 3D conic curve lying on, parameter determination.
基金supported by the National Natural Science Foundation of China(Nos.61171107 and 61271257)General program of science and technology development project of Beijing Municipal Education Commission(Nos.KM201510012005,SQKM201610012008,and SQKM201710012006)+1 种基金the research project of the China Scholarship Council(Nos.201509970037 and 201609970003)Beijing Institute of Fashion Technology College of Special Plan Young Top-notch Talent Project(No.BIFTBJ201803)
文摘Existing mobility models have limitations in their ability to simulate the movement of Wireless Body Area Network(WBAN) since body nodes do not exactly follow either classic mobility models or human contact distributions. In this paper, we propose a new mobility model called Body Gauss–Markov Mobility(BGMM) model,which is oriented specially to WBAN. First, we present the random Gauss-Markov mobility model as the most suitable theoretical basis for developing our new model, as its movement pattern can reveal real human body movements. Next, we examine the transfer of human movement states and derive a simplified mathematical Human Mobility Model(HMM). We then construct the BGMM model by combining the RGMM and HMM models. Finally,we simulate the traces of the new mobility model. We use four direct metrics in our proposed mobility model to evaluate its performance. The simulation results show that the proposed BGMM model performs with respect to the direct mobility metrics and can effectively represent a general WBAN-nodes movement pattern.
基金This work is supported by the National Natural Science Foundation of China(Grant No.51875187,32171305)Hunan YouthTalent Program(Grant No.2020RC3016)+1 种基金Natural Science Foundation of Chongqing(Grant No.cstc2021jcyj-msxmX0109)Chongqing Technology Innovation and Application DevelopmentProject(CSTB2023YSZX-JSX0003).
文摘Purpose:Under-foot impact loadings can cause serious lower limb injuries in many activities,such asautomobile collisions and underbody explosions to military vehicles.The present study aims to comparethe biomechanical responses of the mainstream vehicle occupant dummies with the human body lowerlimb model and analyze their robustness and applicability for assessing lower limb injury risk in underfoot impact loading environments.Methods:The Hybrid III model,the test device for human occupant restraint(THOR)model,and a hybridhuman body model with the human active lower limb model were adopted for under-foot impactanalysis regarding different impact velocities and initial lower limb postures.Results:The results show that the 2 dummy models have larger peak tibial axial force and highersensitivity to the impact velocities and initial postures than the human lower limb model.In particular,the Hybrid III dummy model presented extremely larger peak tibial axial forces than the human lowerlimb model.In the case of minimal difference in tibial axial force,Hybrid III's tibial axial force(7.5 KN)isstill 312.5%that of human active lower limb's(2.4 KN).Even with closer peak tibial axial force values,thebiomechanical response curve shapes of the THOR model show significant differences from the humanlower limb model.Conclusion:Based on the present results,the Hybrid III dummy cannot be used to evaluate the lowerlimb injury risk in under-foot loading environments.In contrast,potential improvement in ankle biofidelity and related soft tissues of the THOR dummy can be implemented in the future for betterapplicability.
基金Supported partially by the National High-Tech Research & Development Program of China (Grant Nos. 2006AA01Z336, 2007AA01Z320)the National Natural Science Foundation of China (Grant No. 60533070)
文摘Virtual human is a digital representation of the geometric and behavioral property of human beings in the virtual environment generated by computer. The research goal of virtual human synthesis is to generate realistic human body models and natural human motion behavior. This paper introduces the development of the related researches on these two topics, and some progresses on example based human modeling and motion synthesis, and their applications in Chinese sign language teaching, computeraided sports training and public safety problem studying. Finally, some hot research topics in virtual human synthesis are presented.
文摘A mechanism-oriented model is proposed here as a speculative but robust attempt to understand whether there might be any increased risk of electrostatically induced contamination,with relevant consequences from the epidemiological viewpoint.This could also be the case for the COVID-19 spreading because an amount of micro-sized droplet nuclei,often carrying net electric charge,are expected to be electro-dynamically involved in a physical process originated by the natural and unperceivable static electrification of human beings.The effects of the triboelectric charging have long been successfully tested because the phenomenon under examination is also implied in the genesis of the electrostatic discharge(ESD),a demanding key objective in the special context of electromagnetic compatibility(EMC).Therefore,the ultimate purpose of this technical paper is to provide valuable insights into infection control,building on what is already being done for maintaining static-safe environments.The stature of the applied model can be further appreciated because some currently observed climate-dependent and sexlinked different vulnerabilities to COVID-19 are critically examined by unique sound arguments.These ultimately focus attention on ambient relative humidity and worn shoes,the latter differing for typology,size and material,for their integrated control of the inadvertent human aptitude to buildup tribocharges.These would appear as a dreadful prerequisite for charge bearing droplets in the airborne state to be efficiently attracted/repelled according to the described electrostatic mechanism.
基金This work is supported by the National Natural Science Foundation of China (60671055, 60331010);Innovation Foundation from Beijing University of Posts and Telecommunications.
文摘A 3-D impedance method has been introduced to compute the electric currents induced in a human body exposed to extremely low-frequency electromagnetic field. The 3-D impedance method has been deduced from Maxwell equations and is put into the computation and simulation effectively to the visible human body model, which has 196×114×626 cells and more than 40 types of tissues. As the result, two representative cases are investigated. One is exposure of the human body to 100 μT (1 000 mG), the limit recommended by the International Commission on Non-Ionizing Radiation Protection for the public and the other one is the exposure of human body to 0.4 laT (4 mG), the level at which a statistical link appears with a doubled risk of development of childhood leukaemia. The distribution of induced current density can be obtained and the maximum of induced current are found to be 16 mA/m^2 and 0.07 mA/m^2.
基金supported by the National Natural Science Foundation of China(No.60927006)
文摘The human body model(HBM) stress of a no-connect metal cover is tested to obtain the characteristics of abnormal electrostatic discharge,including current waveforms and peak current under varied stress voltage and device failure voltage.A new discharge model called the "sparkover-induced model" is proposed based on the results.Then,failure mechanism analysis and model simulation are performed to prove that the transient peak current caused by a sparkover of low arc impedance will result in the devices' premature damage when the potential difference between the no-connect metal cover and the chip exceeds the threshold voltage of sparkover.