The Rapidly-exploring Random Tree(RRT)algorithm is an efficient path-planning algorithm based on random sampling.The RRT^(*)algorithm is a variant of the RRT algorithm that can achieve convergence to the optimal solut...The Rapidly-exploring Random Tree(RRT)algorithm is an efficient path-planning algorithm based on random sampling.The RRT^(*)algorithm is a variant of the RRT algorithm that can achieve convergence to the optimal solution.However,it has been proven to take an infinite time to do so.An improved Quick-RRT^(*)(Q-RRT^(*))algorithm based on a virtual light source is proposed in this paper to overcome this problem.The virtual light-based Q-RRT^(*)(LQRRT^(*))takes advantage of the heuristic information generated by the virtual light on the map.In this way,the tree can find the initial solution quickly.Next,the LQRRT^(*)algorithm combines the heuristic information with the optimization capability of the Q-RRT^(*)algorithm to find the approximate optimal solution.LQRRT^(*)further optimizes the sampling space compared with the Q-RRT^(*)algorithm and improves the sampling efficiency.The efficiency of the algorithm is verified by comparison experiments in different simulation environments.The results show that the proposed algorithm can converge to the approximate optimal solution in less time and with lower memory consumption.展开更多
We examine the network performance of algorithms for self-organized traffic management. In particular, we focus on wireless network- ing between cars. One of many technologies that make road traffic safer and more eff...We examine the network performance of algorithms for self-organized traffic management. In particular, we focus on wireless network- ing between cars. One of many technologies that make road traffic safer and more efficient is the Virtual Traffic Light （VTL） system, which is able to coordinate the traffic flow at intersections without the need for physical lights. VTL takes a leading vehicle at an inter- section and uses it to control the traffic lights. We developed algorithms for leader election and traffic light computation in realistic ve- hicular networking scenarios. Our key contribution is the extension of this algorithm to support arbitrary intersection layouts. We in- vestigated the proposal in synthetic and realistic scenarios. The results show that, overall, VTLs use network resources efficiently and positively influences driving experience. It performs better than stationary traffic lights for a low to medium network load. We also identify potential optimizations to deal with high network load and to improve fairness.展开更多
Large cities suffer from traffic congestion,particularly at intersections,due to a large number of vehicles,which leads to the loss of time by increasing carbon emissions,including fuel consumption.Therefore,the need ...Large cities suffer from traffic congestion,particularly at intersections,due to a large number of vehicles,which leads to the loss of time by increasing carbon emissions,including fuel consumption.Therefore,the need for optimising the flow of vehicles at different intersections and reducing the waiting time is a critical challenge.Conventional traffic lights have been used to control traffic flow at different intersections and have been improved to become more efficient by using different algorithms,sensors and cameras.However,they also face some challenges,such as high-cost installation,operation,and maintenance issues.This paper develops a new system based on the Virtual Traffic Light(VTL)technology to improve traffic flow at different intersections and reduce the encountered loss of time and vehicles’travel time.Additionally,it reduces the costs of installation,maintenance and operation over various conventional traffic light systems.Consequently,the system proposes algorithms for traffic scheduling and lane identification by using vehicle ID,priority and time of arrival.To evaluate the system,four scenarios were presented where each scenario uses a different number of vehicles consisting of three types(emergency vehicles,public buses and private vehicles),each given a different priority.The proposed system is evaluated by integrating two simulators,namely,(OMNeT++)and(SUMO),and two frameworks,namely,(VEINS)and(INET)to prepare an appropriate working environment.the results prove that an improvement in the average travel time for several vehicles reaches 44.43%–49.76%compared with conventional traffic lights.Further,it is proven from the obtained results that the average waiting time for emergency vehicles is enhanced by 96.63%–97.63%,while the average waiting time for public buses is improved by 94.81%–97.23%.On the other hand,the waiting time for private vehicles‘improved by 87.14%to 89.71%’.展开更多
Based on a virtual spherical light source method, this paper presents an improved virtual spherical lights approach for glossy illumination by modifying a reflection render equation. First, in order to keep primitive ...Based on a virtual spherical light source method, this paper presents an improved virtual spherical lights approach for glossy illumination by modifying a reflection render equation. First, in order to keep primitive spherical lights, it uses non-zero solid angle integration instead of a geometric item of traditional Instant Radiosity arithmetic. Second, the formula mode for the light energy allocation of VSLs is improved by the energy distribution, in which the radius of sphere is replaced by the radius of inscribed circle generated by the tangent to the non-zero solid angle of cone. Third, the similar function of judging two point visibility takes place of a cosine term in the approximate equations of the VSLs. Experiments show that blurring or disappearing phenomenon that appear in part of right-angle surface scene is avoided.展开更多
With the development of virtual reality (VR) technology, more and more industries are beginning to integrate with VR technology. In response to the problem of not being able to directly render the lighting effect of C...With the development of virtual reality (VR) technology, more and more industries are beginning to integrate with VR technology. In response to the problem of not being able to directly render the lighting effect of Caideng in digital Caideng scenes, this article analyzes the lighting model. It combines it with the lighting effect of Caideng scenes to design an optimized lighting model algorithm that fuses the bidirectional transmission distribution function (BTDF) model. This algorithm can efficiently render the lighting effect of Caideng models in a virtual environment. And using image optimization processing methods, the immersive experience effect on the VR is enhanced. Finally, a Caideng roaming interactive system was designed based on this method. The results show that the frame rate of the system is stable during operation, maintained above 60 fps, and has a good immersive experience.展开更多
This article reports a case of dysarthria which was successfully treated by Strannik Light Therapy (SLT). It briefly discusses the known etiology for the condition and illustrates that dysarthria must be a problem of ...This article reports a case of dysarthria which was successfully treated by Strannik Light Therapy (SLT). It briefly discusses the known etiology for the condition and illustrates that dysarthria must be a problem of autonomic dysfunction in which pathological changes can influence the structure and/or subsequent function of the dynamic interplay between the brain and the organs involving the autonomic nervous system and physiological systems. The author reports a particular case in which a patient undertaking SLT fully recovered the ability to speak within 6 days.展开更多
基金This work was supported by the Natural Science Foundation of the Jiangsu Higher Education Institutions of China[grant number 19KJB510022]the Startup Research Foundation for Advanced Talents[grant number JSPIGKZ/2911119220].
文摘The Rapidly-exploring Random Tree(RRT)algorithm is an efficient path-planning algorithm based on random sampling.The RRT^(*)algorithm is a variant of the RRT algorithm that can achieve convergence to the optimal solution.However,it has been proven to take an infinite time to do so.An improved Quick-RRT^(*)(Q-RRT^(*))algorithm based on a virtual light source is proposed in this paper to overcome this problem.The virtual light-based Q-RRT^(*)(LQRRT^(*))takes advantage of the heuristic information generated by the virtual light on the map.In this way,the tree can find the initial solution quickly.Next,the LQRRT^(*)algorithm combines the heuristic information with the optimization capability of the Q-RRT^(*)algorithm to find the approximate optimal solution.LQRRT^(*)further optimizes the sampling space compared with the Q-RRT^(*)algorithm and improves the sampling efficiency.The efficiency of the algorithm is verified by comparison experiments in different simulation environments.The results show that the proposed algorithm can converge to the approximate optimal solution in less time and with lower memory consumption.
文摘We examine the network performance of algorithms for self-organized traffic management. In particular, we focus on wireless network- ing between cars. One of many technologies that make road traffic safer and more efficient is the Virtual Traffic Light （VTL） system, which is able to coordinate the traffic flow at intersections without the need for physical lights. VTL takes a leading vehicle at an inter- section and uses it to control the traffic lights. We developed algorithms for leader election and traffic light computation in realistic ve- hicular networking scenarios. Our key contribution is the extension of this algorithm to support arbitrary intersection layouts. We in- vestigated the proposal in synthetic and realistic scenarios. The results show that, overall, VTLs use network resources efficiently and positively influences driving experience. It performs better than stationary traffic lights for a low to medium network load. We also identify potential optimizations to deal with high network load and to improve fairness.
文摘Large cities suffer from traffic congestion,particularly at intersections,due to a large number of vehicles,which leads to the loss of time by increasing carbon emissions,including fuel consumption.Therefore,the need for optimising the flow of vehicles at different intersections and reducing the waiting time is a critical challenge.Conventional traffic lights have been used to control traffic flow at different intersections and have been improved to become more efficient by using different algorithms,sensors and cameras.However,they also face some challenges,such as high-cost installation,operation,and maintenance issues.This paper develops a new system based on the Virtual Traffic Light(VTL)technology to improve traffic flow at different intersections and reduce the encountered loss of time and vehicles’travel time.Additionally,it reduces the costs of installation,maintenance and operation over various conventional traffic light systems.Consequently,the system proposes algorithms for traffic scheduling and lane identification by using vehicle ID,priority and time of arrival.To evaluate the system,four scenarios were presented where each scenario uses a different number of vehicles consisting of three types(emergency vehicles,public buses and private vehicles),each given a different priority.The proposed system is evaluated by integrating two simulators,namely,(OMNeT++)and(SUMO),and two frameworks,namely,(VEINS)and(INET)to prepare an appropriate working environment.the results prove that an improvement in the average travel time for several vehicles reaches 44.43%–49.76%compared with conventional traffic lights.Further,it is proven from the obtained results that the average waiting time for emergency vehicles is enhanced by 96.63%–97.63%,while the average waiting time for public buses is improved by 94.81%–97.23%.On the other hand,the waiting time for private vehicles‘improved by 87.14%to 89.71%’.
基金Supported by the Program for New Jinzhou District Science and Technology Research(No.2013-GX1-015)the Scientific Research Fund of Liaoning Provincial Education Department(No.L2013459)
文摘Based on a virtual spherical light source method, this paper presents an improved virtual spherical lights approach for glossy illumination by modifying a reflection render equation. First, in order to keep primitive spherical lights, it uses non-zero solid angle integration instead of a geometric item of traditional Instant Radiosity arithmetic. Second, the formula mode for the light energy allocation of VSLs is improved by the energy distribution, in which the radius of sphere is replaced by the radius of inscribed circle generated by the tangent to the non-zero solid angle of cone. Third, the similar function of judging two point visibility takes place of a cosine term in the approximate equations of the VSLs. Experiments show that blurring or disappearing phenomenon that appear in part of right-angle surface scene is avoided.
文摘With the development of virtual reality (VR) technology, more and more industries are beginning to integrate with VR technology. In response to the problem of not being able to directly render the lighting effect of Caideng in digital Caideng scenes, this article analyzes the lighting model. It combines it with the lighting effect of Caideng scenes to design an optimized lighting model algorithm that fuses the bidirectional transmission distribution function (BTDF) model. This algorithm can efficiently render the lighting effect of Caideng models in a virtual environment. And using image optimization processing methods, the immersive experience effect on the VR is enhanced. Finally, a Caideng roaming interactive system was designed based on this method. The results show that the frame rate of the system is stable during operation, maintained above 60 fps, and has a good immersive experience.
文摘This article reports a case of dysarthria which was successfully treated by Strannik Light Therapy (SLT). It briefly discusses the known etiology for the condition and illustrates that dysarthria must be a problem of autonomic dysfunction in which pathological changes can influence the structure and/or subsequent function of the dynamic interplay between the brain and the organs involving the autonomic nervous system and physiological systems. The author reports a particular case in which a patient undertaking SLT fully recovered the ability to speak within 6 days.
