The paper describes the feasibility and method of the application of virtual reality technology to grinding process, and introduces the modeling method of object entity in the environment of virtual reality. The simul...The paper describes the feasibility and method of the application of virtual reality technology to grinding process, and introduces the modeling method of object entity in the environment of virtual reality. The simulation process of grinding wheels and ground surface roughness is discussed, and the computation program system of numerical simulation is compiled with Visual C++ programming language. At the same time, the three-dimensional simulation models of grinding wheels and ground surface roughness are made with OpenGL tool. The choice of grinding wheels, the forecast of ground surface quality and some simulation results can be realized by interactively inputting grinding parameters. The paper applies virtual reality technology to grinding process,makes the model of virtual grinding wheel and simulates the grinding process. The roughness of ground surface is showed in three-dimensional images, and therefore the grinding technology is studied. Computer simulation can not only be used as a shortcut to analyze and research the grinding process, but also increase the research scope and content. The virtual reality technology used in the paper is an advanced visualized simulation with interaction. The surface roughness Ra on simulated ground workpiece can be calculated by the arithmetic average of contour warp absolute value in sampling length of simulated ground workpiece. The parameters of virtual wheel and simulated grinding process can be changed by interaction input, so the simulated results in the desired grinding condition are gained. The effect of each parameter to ground surface can be analyzed by comparing the grinding results in different condition.展开更多
Long-time driving and monotonous visual environment increase the safety risk of driving in an extra-long tunnel.Driving fatigue can be effectively relieved by setting the visual fatigue relief zone in the tunnel.Howev...Long-time driving and monotonous visual environment increase the safety risk of driving in an extra-long tunnel.Driving fatigue can be effectively relieved by setting the visual fatigue relief zone in the tunnel.However,the setting form of visual fatigue relief zone,such as its length and location,is difficult to be designed and quantified.By integrating virtual reality(VR)apparatus with wearable electroencephalogram(EEG)-based devices,a hybrid method was proposed in this study to assist analyzers to formulate the layout of visual fatigue relief zone in the extra-long tunnel.The virtual environment of this study was based on an 11.5 km extra-long tunnel located in Yunnan Province in China.The results indicated that the use of natural landscape decoration inside the tunnel could improve driving fatigue with the growth rate of attention of the driver increased by more than 20%.The accumulation of driving fatigue had a negative effect on the fatigue relief.The results demonstrated that the optimal location of the fatigue relief zone was at the place where driving fatigue had just occurred rather than at the place where a certain amount of driving fatigue had accumulated.展开更多
The pincipl of a 6 DOF (degress of freedom) input device using ultrasonic distance measurement is presented in this paper. The system employs the method of measuring the time of flight. In addition, some techniques, i...The pincipl of a 6 DOF (degress of freedom) input device using ultrasonic distance measurement is presented in this paper. The system employs the method of measuring the time of flight. In addition, some techniques, including automatic gain control, self-adaptive variable threshold and temperature compensation, are also used to improve precision. Then, the positions and orientation of the input device can be calculated by the method of spatial analytic geometry. Meanwhile, commands from the 3-D input device are detected and carried out. The validity and precision of the input device are verified by the experiment in a robot system. The proposed device not only can be used for end effector position and orientation measurement in telerobotics, but also can be an interactive device in virtual reality systems, such as helmet tracking, viewpoint navigation and object manipulation.展开更多
Generally speaking, "an economic circle" refers to a group of countriesand regions whose economic relations override the universally accepted in-ternational practice or norms and they have formulated new eco...Generally speaking, "an economic circle" refers to a group of countriesand regions whose economic relations override the universally accepted in-ternational practice or norms and they have formulated new economic ruleswhich are applicable only to countries and regions inside the circle.展开更多
The comprehensive evaluation of six properties for equipment product is an important basis for their quality control,and their correlative relationship among six properties will affect their quality level.To understan...The comprehensive evaluation of six properties for equipment product is an important basis for their quality control,and their correlative relationship among six properties will affect their quality level.To understand their correlative relationship among six properties,this paper firstly combines group evaluation with decision-making trial and evaluation laboratory(DEMATEL)model,and develops the optimization model based on group consensus to form six influent relationship matrices.Secondly,group consensus matrix is used to design super network hierarchy matrix,and the weights of six properties with relevant environment is also proposed.Thirdly,the elimination and choice translating reality(ELECTRE)model is used to make comprehensive evaluation,and an example is used to compare the results under two kinds of conditions,and illustrate the effect of the weights of six properties on the priority of equipment products.展开更多
主持人语：3D打印亦称增材制造。3D设计的开放化、数字制造的社会化、3D打印机的商用化使人类跨越从＂虚拟到现实＂（ virtual to reality ）、从＂创意到产品＂（ mind to product ）的鸿沟，通过DIY打开了比特向原子（ bits to atoms...主持人语：3D打印亦称增材制造。3D设计的开放化、数字制造的社会化、3D打印机的商用化使人类跨越从＂虚拟到现实＂（ virtual to reality ）、从＂创意到产品＂（ mind to product ）的鸿沟，通过DIY打开了比特向原子（ bits to atoms）复归的大门，自此撩开3D打印侵犯知识产权的神秘面纱。3D打印技术作为一种新型的复制手段，将对著作权法产生何种影响？专利法如何回应社会制造对专利产品修理再造规则的挑战？怎样完善3D打印专利间接侵权在客观行为、主观意图和行为后果等方面的认定标准？商标法岂能防止3D打印导致的商标功能淡化抑或贬损？<br> 华中科技大学是国内率先从事3D打印和知识产权教学研究的高校之一，针对3D打印技术发展与知识产权制度的变革，做了大量的前期研究工作。本期专题冀通过对上述问题的探讨，从中一览知识产权制度应对3D打印技术发展的概貌。展开更多
Augmented solar images were used to research the adaptability of four representative image extraction and matching algorithms in space weather domain.These include the scale-invariant feature transform algorithm,speed...Augmented solar images were used to research the adaptability of four representative image extraction and matching algorithms in space weather domain.These include the scale-invariant feature transform algorithm,speeded-up robust features algorithm,binary robust invariant scalable keypoints algorithm,and oriented fast and rotated brief algorithm.The performance of these algorithms was estimated in terms of matching accuracy,feature point richness,and running time.The experiment result showed that no algorithm achieved high accuracy while keeping low running time,and all algorithms are not suitable for image feature extraction and matching of augmented solar images.To solve this problem,an improved method was proposed by using two-frame matching to utilize the accuracy advantage of the scale-invariant feature transform algorithm and the speed advantage of the oriented fast and rotated brief algorithm.Furthermore,our method and the four representative algorithms were applied to augmented solar images.Our application experiments proved that our method achieved a similar high recognition rate to the scale-invariant feature transform algorithm which is significantly higher than other algorithms.Our method also obtained a similar low running time to the oriented fast and rotated brief algorithm,which is significantly lower than other algorithms.展开更多
The scientific research on Qinghai—Tibet Plateau has already been the hot and key point on the plateau evolvement, the earth ecological variety, as well as the society harmonious development. The research on Qinghai...The scientific research on Qinghai—Tibet Plateau has already been the hot and key point on the plateau evolvement, the earth ecological variety, as well as the society harmonious development. The research on Qinghai—Tibet Plateau has the following characteristics:(1) 4\|dimension of time and space: with a vast territory and very deep depth, as well as the big time span.(2) Wide fields and across subjects: including geology, environment, ecology, climate, land, agriculture, forestry, animal husbandry, etc.(3) Theory and practice with profound and lasting influence: the research results can be great function for the direction in understanding the world, ecological environment and the human living conditions.The current issues of the research on Qinghai—Tibet Plateau are as follows:(1) Thousands of papers concerned about Qinghai—Tibet Plateau are lack of quantification data, and the research results are not displayed vividly.(2) The study scopes are more in the portion and less in the whole.(3) There are not enough work of combination of depth study with surface study, the representation in 3\|D is limited.(4) The study of time variation is not enough and there is poor way to show the time series results.(5) There are not enough work in the different specialties intercross, as well as the synthesis study of interdisciplinary subjects and cross subjects.展开更多
·Safer＇chemsex＇：GPs＇role in harm reduction for emerging forms of recreational drug use安全＂chemsex＂：全科医生在减少新兴形式毒品伤害方面的作用·Managing older people＇s alcohol misuse in primary care初...·Safer＇chemsex＇：GPs＇role in harm reduction for emerging forms of recreational drug use安全＂chemsex＂：全科医生在减少新兴形式毒品伤害方面的作用·Managing older people＇s alcohol misuse in primary care初级医疗对老年人乙醇滥用的管理·The role of general practice in following up patients with trauma全科医生在创伤患者随访中的作用·Rhetoric and reality in person-centred care：introducing the House of Care framework以人为中心护理的修辞和现实：展开更多
Immersive virtual product development is a new desi gn , developing and evaluation method of integrated product and processing tragedie s, which using VR, multi-discipline simulation and scientific visualization tec h...Immersive virtual product development is a new desi gn , developing and evaluation method of integrated product and processing tragedie s, which using VR, multi-discipline simulation and scientific visualization tec hnologies. Users may have the experiences of being part of a cyberspace environm ent with the ability to navigate and manipulate objects which have properties an d behaviors that correspond to those of the real world objects. We present a fra mework and prototype system of an immerse VPD (IVPD) which enables users to navi gate and interact with 3D peripherals with the display system. The framework of IVPD which we have defined can meet these requirements. In the immersive virtual environment, design will include four main parts: 3D CAD/modeler, multidiscipli ne simulations, CAM and discrete system simulation. 3D CAD/modeler can create 3D geometric objects and import models from other commercial softwares such as UG, CATIA etc. It can also store all kinds of models into databases with hierarchy which will provide geometric models with simulations and evaluations in later pr ocedures. Multidiscipline simulations can integrate many simulations such as FEA , CFD, Noisy and etc. Each kind of these simulation softwares will reflect a cer tain aspect of product or component’s performances. CAM, as a successor of prod uct development, mainly simulates the manufacturing procedures in the computer. Discrete system simulation will able to see the layout problems for a factory. I t is very useful for production management. Participants may actively view the v irtual world revolving around them while others control navigation and simul ations, and may interact with other members such as pass an object from one embo died manikin to another.展开更多
文摘The paper describes the feasibility and method of the application of virtual reality technology to grinding process, and introduces the modeling method of object entity in the environment of virtual reality. The simulation process of grinding wheels and ground surface roughness is discussed, and the computation program system of numerical simulation is compiled with Visual C++ programming language. At the same time, the three-dimensional simulation models of grinding wheels and ground surface roughness are made with OpenGL tool. The choice of grinding wheels, the forecast of ground surface quality and some simulation results can be realized by interactively inputting grinding parameters. The paper applies virtual reality technology to grinding process,makes the model of virtual grinding wheel and simulates the grinding process. The roughness of ground surface is showed in three-dimensional images, and therefore the grinding technology is studied. Computer simulation can not only be used as a shortcut to analyze and research the grinding process, but also increase the research scope and content. The virtual reality technology used in the paper is an advanced visualized simulation with interaction. The surface roughness Ra on simulated ground workpiece can be calculated by the arithmetic average of contour warp absolute value in sampling length of simulated ground workpiece. The parameters of virtual wheel and simulated grinding process can be changed by interaction input, so the simulated results in the desired grinding condition are gained. The effect of each parameter to ground surface can be analyzed by comparing the grinding results in different condition.
基金Project(2018YFB2101000) supported by the National Key R&D Program of ChinaProject(20YF1451400) supported by Shanghai Sailing Program,ChinaProject(SLDRCE19-A-14) supported by the Research Fund of State Key Laboratory for Disaster Reduction in Civil Engineering,China。
文摘Long-time driving and monotonous visual environment increase the safety risk of driving in an extra-long tunnel.Driving fatigue can be effectively relieved by setting the visual fatigue relief zone in the tunnel.However,the setting form of visual fatigue relief zone,such as its length and location,is difficult to be designed and quantified.By integrating virtual reality(VR)apparatus with wearable electroencephalogram(EEG)-based devices,a hybrid method was proposed in this study to assist analyzers to formulate the layout of visual fatigue relief zone in the extra-long tunnel.The virtual environment of this study was based on an 11.5 km extra-long tunnel located in Yunnan Province in China.The results indicated that the use of natural landscape decoration inside the tunnel could improve driving fatigue with the growth rate of attention of the driver increased by more than 20%.The accumulation of driving fatigue had a negative effect on the fatigue relief.The results demonstrated that the optimal location of the fatigue relief zone was at the place where driving fatigue had just occurred rather than at the place where a certain amount of driving fatigue had accumulated.
文摘The pincipl of a 6 DOF (degress of freedom) input device using ultrasonic distance measurement is presented in this paper. The system employs the method of measuring the time of flight. In addition, some techniques, including automatic gain control, self-adaptive variable threshold and temperature compensation, are also used to improve precision. Then, the positions and orientation of the input device can be calculated by the method of spatial analytic geometry. Meanwhile, commands from the 3-D input device are detected and carried out. The validity and precision of the input device are verified by the experiment in a robot system. The proposed device not only can be used for end effector position and orientation measurement in telerobotics, but also can be an interactive device in virtual reality systems, such as helmet tracking, viewpoint navigation and object manipulation.
文摘Generally speaking, "an economic circle" refers to a group of countriesand regions whose economic relations override the universally accepted in-ternational practice or norms and they have formulated new economic ruleswhich are applicable only to countries and regions inside the circle.
文摘The comprehensive evaluation of six properties for equipment product is an important basis for their quality control,and their correlative relationship among six properties will affect their quality level.To understand their correlative relationship among six properties,this paper firstly combines group evaluation with decision-making trial and evaluation laboratory(DEMATEL)model,and develops the optimization model based on group consensus to form six influent relationship matrices.Secondly,group consensus matrix is used to design super network hierarchy matrix,and the weights of six properties with relevant environment is also proposed.Thirdly,the elimination and choice translating reality(ELECTRE)model is used to make comprehensive evaluation,and an example is used to compare the results under two kinds of conditions,and illustrate the effect of the weights of six properties on the priority of equipment products.
文摘主持人语：3D打印亦称增材制造。3D设计的开放化、数字制造的社会化、3D打印机的商用化使人类跨越从＂虚拟到现实＂（ virtual to reality ）、从＂创意到产品＂（ mind to product ）的鸿沟，通过DIY打开了比特向原子（ bits to atoms）复归的大门，自此撩开3D打印侵犯知识产权的神秘面纱。3D打印技术作为一种新型的复制手段，将对著作权法产生何种影响？专利法如何回应社会制造对专利产品修理再造规则的挑战？怎样完善3D打印专利间接侵权在客观行为、主观意图和行为后果等方面的认定标准？商标法岂能防止3D打印导致的商标功能淡化抑或贬损？<br> 华中科技大学是国内率先从事3D打印和知识产权教学研究的高校之一，针对3D打印技术发展与知识产权制度的变革，做了大量的前期研究工作。本期专题冀通过对上述问题的探讨，从中一览知识产权制度应对3D打印技术发展的概貌。
基金Supported by the Key Research Program of the Chinese Academy of Sciences(ZDRE-KT-2021-3)。
文摘Augmented solar images were used to research the adaptability of four representative image extraction and matching algorithms in space weather domain.These include the scale-invariant feature transform algorithm,speeded-up robust features algorithm,binary robust invariant scalable keypoints algorithm,and oriented fast and rotated brief algorithm.The performance of these algorithms was estimated in terms of matching accuracy,feature point richness,and running time.The experiment result showed that no algorithm achieved high accuracy while keeping low running time,and all algorithms are not suitable for image feature extraction and matching of augmented solar images.To solve this problem,an improved method was proposed by using two-frame matching to utilize the accuracy advantage of the scale-invariant feature transform algorithm and the speed advantage of the oriented fast and rotated brief algorithm.Furthermore,our method and the four representative algorithms were applied to augmented solar images.Our application experiments proved that our method achieved a similar high recognition rate to the scale-invariant feature transform algorithm which is significantly higher than other algorithms.Our method also obtained a similar low running time to the oriented fast and rotated brief algorithm,which is significantly lower than other algorithms.
文摘The scientific research on Qinghai—Tibet Plateau has already been the hot and key point on the plateau evolvement, the earth ecological variety, as well as the society harmonious development. The research on Qinghai—Tibet Plateau has the following characteristics:(1) 4\|dimension of time and space: with a vast territory and very deep depth, as well as the big time span.(2) Wide fields and across subjects: including geology, environment, ecology, climate, land, agriculture, forestry, animal husbandry, etc.(3) Theory and practice with profound and lasting influence: the research results can be great function for the direction in understanding the world, ecological environment and the human living conditions.The current issues of the research on Qinghai—Tibet Plateau are as follows:(1) Thousands of papers concerned about Qinghai—Tibet Plateau are lack of quantification data, and the research results are not displayed vividly.(2) The study scopes are more in the portion and less in the whole.(3) There are not enough work of combination of depth study with surface study, the representation in 3\|D is limited.(4) The study of time variation is not enough and there is poor way to show the time series results.(5) There are not enough work in the different specialties intercross, as well as the synthesis study of interdisciplinary subjects and cross subjects.
文摘·Safer＇chemsex＇：GPs＇role in harm reduction for emerging forms of recreational drug use安全＂chemsex＂：全科医生在减少新兴形式毒品伤害方面的作用·Managing older people＇s alcohol misuse in primary care初级医疗对老年人乙醇滥用的管理·The role of general practice in following up patients with trauma全科医生在创伤患者随访中的作用·Rhetoric and reality in person-centred care：introducing the House of Care framework以人为中心护理的修辞和现实：
文摘Immersive virtual product development is a new desi gn , developing and evaluation method of integrated product and processing tragedie s, which using VR, multi-discipline simulation and scientific visualization tec hnologies. Users may have the experiences of being part of a cyberspace environm ent with the ability to navigate and manipulate objects which have properties an d behaviors that correspond to those of the real world objects. We present a fra mework and prototype system of an immerse VPD (IVPD) which enables users to navi gate and interact with 3D peripherals with the display system. The framework of IVPD which we have defined can meet these requirements. In the immersive virtual environment, design will include four main parts: 3D CAD/modeler, multidiscipli ne simulations, CAM and discrete system simulation. 3D CAD/modeler can create 3D geometric objects and import models from other commercial softwares such as UG, CATIA etc. It can also store all kinds of models into databases with hierarchy which will provide geometric models with simulations and evaluations in later pr ocedures. Multidiscipline simulations can integrate many simulations such as FEA , CFD, Noisy and etc. Each kind of these simulation softwares will reflect a cer tain aspect of product or component’s performances. CAM, as a successor of prod uct development, mainly simulates the manufacturing procedures in the computer. Discrete system simulation will able to see the layout problems for a factory. I t is very useful for production management. Participants may actively view the v irtual world revolving around them while others control navigation and simul ations, and may interact with other members such as pass an object from one embo died manikin to another.
