Background: Wrist pain is prevalent. Activities such as dexterous sports, prolonged use of personal handheld devices, and extensive desktop keyboard usage are common contributors to wrist pain. Intersection syndrome, ...Background: Wrist pain is prevalent. Activities such as dexterous sports, prolonged use of personal handheld devices, and extensive desktop keyboard usage are common contributors to wrist pain. Intersection syndrome, a form of inflammatory tenosynovitis, occurs at the intersection of the first and second dorsal compartments of the wrist. The first dorsal compartment is comprised of the tendons of abductor pollicis longus and extensor pollicis brevis, while the second dorsal compartment contains the tendons of extensor carpi radialis longus and extensor carpi radialis brevis. Intersection syndrome is diagnosed by pain localized to the dorsoradial forearm, approximately five cm proximal to the wrist joint, which worsens with resisted wrist and thumb extension. To date, the use of hydro dissection with 5% dextrose under ultrasound guidance as a treatment for Intersection syndrome has not been reported. This case report presents the first report on ultrasound-guided hydro dissection as a therapeutic approach for intersection syndrome. Methods: A case report, with informed consent, involving a 32-year-old male athlete. The patient, a hurling player, presented with chronic right wrist pain diagnosed as intersection syndrome. The condition significantly affected his work, sporting activities, and daily living activities. Previous conservative management and physiotherapy had failed to alleviate his symptoms. To confirm the diagnosis, relevant imaging was performed, supplemented by dynamic ultrasound assessment. The procedure was performed aseptically. Continuous ultrasound guidance was employed to ensure accurate needle placement. Once the needle tip position was confirmed, an initial injection of 5 mL of 0.25% chirocaine was administered. 10 mL of 5% dextrose was injected under ultrasound guidance for hydro dissection, with good visualization of the solution’s distribution. Conclusion: Ultrasound-guided hydro dissection has not previously been documented as a treatment option for intersection syndrome. In this case, it proved to be an effective pain-relieving therapy with sustained effect at three-month clinical follow-up. Further studies are required.展开更多
The intersection is a widely used traffic line structure from the shallow tunnel to the deep roadway,and determining the subsidence hidden danger area of the roof is the key to its stability control.However,applying t...The intersection is a widely used traffic line structure from the shallow tunnel to the deep roadway,and determining the subsidence hidden danger area of the roof is the key to its stability control.However,applying traditional maximum equivalent span beam(MESB)theory to determine deformation range,peak point,and angle influence poses a challenge.Considering the overall structure of the intersection roof,the maximum equivalent triangular plate(METP)theory is proposed,and its geometric parameter calculation formula and deflection calculation formula are obtained.The application of the two theories in 18 models with different intersection angles,roadway types,and surrounding rock lithology is verified by numerical analysis.The results show that:1)The METP structure of the intersection roof established by the simulation results of each model successfully determined the location of the roof’s high displacement zone;2)The area comparison method of the METP theory can be reasonably explained:①The roof subsidence of the intersection decreases with the increase of the intersection angle;②The roof subsidence at the intersection of different roadway types has a rectangular type>arch type>circular type;③The roof subsidence of the intersection with weak surrounding rock is significantly larger than that of the intersection with hard surrounding rock.According to the application results of the two theories,the four advantages of the METP theory are compared and clarified in the basic assumptions,mechanical models,main viewpoints,and mechanism analysis.The large deformation inducement of the intersection roof is then explored.The J 2 peak area of the roof drives the large deformation of the area,the peak point of which is consistent with the center of gravity position of the METP.Furthermore,the change in the range of this peak is consistent with the change law of the METP’s area.Hence,this theory clarifies the large deformation area of the intersection roof,which provides a clear guiding basis for its initial support design,mid-term monitoring,and late local reinforcement.展开更多
This article explores the intersections of Buddhism,Daoism,and contemporary French literary practice in the study of the everyday(quotidien).Since the 1980s,French literature has increasingly shifted its focus from th...This article explores the intersections of Buddhism,Daoism,and contemporary French literary practice in the study of the everyday(quotidien).Since the 1980s,French literature has increasingly shifted its focus from the exotic to the mundane,engaging with theoretical frameworks developed by scholars such as Henri Lefebvre and Michel de Certeau.Drawing on Buddhist notions of emptiness and dependent arising,as well as Daoist principles of yin-yang interdependence,the article bridges Eastern and Western philosophies to demonstrate the everyday not as a static or trivial backdrop,but as a dynamic and transformative space.It further examines how representations of daily life in the works of Georges Perec and Jacques Roubaud employ the meticulous documentation of mundane details to uncover hidden patterns,rhythms,and structures of human experience.Through literary fieldwork,Perec and Roubaud challenge conventional perceptions of the everyday,unveiling its depth,complexity,and potential for reinvention.展开更多
In the next few years traffic will happen most of the time.This was triggered by the growing rate of vehicles against the road capacity which is not balance.All the time the congestion in the city of Semarang has occu...In the next few years traffic will happen most of the time.This was triggered by the growing rate of vehicles against the road capacity which is not balance.All the time the congestion in the city of Semarang has occured at peak hours.Congestion also occured in between Teuku Umar and Setia Budi road Jatingaleh because of a plot intersection(Kesatrian intersection,PLN intersection and Jatingaleh intersection)with the Toll Road.Jatingaleh is located in the southern city of Semarang which is a central meeting point between the upper and lower Semarang where the vehicle flows in through a combination of local current and regional traffic,and the flow of vehicles coming in and out from highway.The main cause of the problems that occurred in the area of Jatingaleh is due to the numbers of vehicles movement that occurs at the intersections.With the above issues,it is necessary to analyse the existing conditions and look into some solutions.Before carrying out an analysis a field surveys at peak hours for example morning(06:00 to 08:00 am)and for the afternoon(04:00 to 06:00 pm)should be conducted,then the number of vehicles is counted manually with“short-breakcounting”according to types of vehicles.From the analysis we found that the degree of saturation(DS)is 1.61 between Teuku Umar and Setia Budi road during the morning peak hours and 1.56 during the afternoon peak hours.This means that the capacity of the existing road is no longer able to accommodate the traffic flow.One of the solutions for the congestion that occurs at the intersection of Jatingaleh is to apply the efficiency of the intersection that is not in a plot with a Fly over,Underpass and the combination of Fly Over-Underpass.Base on the flow reduction calculation with 3 comparative modeling it shows that the Fly Over is the most technically efficient to be applied in this research.展开更多
In this paper,we introduce the normalized L,mixed intersection body and demonstrate how the normalized L_(p) mixed intersection body operator can be used to obtain the polar body operator as a limit.Moreover,we study ...In this paper,we introduce the normalized L,mixed intersection body and demonstrate how the normalized L_(p) mixed intersection body operator can be used to obtain the polar body operator as a limit.Moreover,we study the L_(p)-Busemann-Petty type problem for the normalized L_(p) mixed intersection bodies.展开更多
Dynamic recrystallization(DRX)is of great significance for the thermomechanical processing and microstructural regulation of TiAl intermetallics.However,the underlying DRX mechanism remains poorly understood.In this s...Dynamic recrystallization(DRX)is of great significance for the thermomechanical processing and microstructural regulation of TiAl intermetallics.However,the underlying DRX mechanism remains poorly understood.In this study,an Avrami kinetics model for DRX was established,which was capable of predicting the DRX fraction accurately.In addition,the effect of Al_(2)O_(3)short fiber on the DRX mechanisms of TiAl matrix composite during the isothermal compression was investigated for the first time.The re-sults showed that other than inhibiting DRX by particles in the TiAl matrix composites,the addition of Al_(2)O_(3)short fiber accelerated a novel DRX process,which was induced by twinning and twin intersec-tions(TDRX).Thus,this composite exhibited a higher DRX rate than that of the as-cast TiAl monolithic alloy.The origin of the twin intersection and TDRX for the composite was revealed.The stress concentration near the Al_(2)O_(3)fiber was above the critical shear stress for twinning and thus was favorable for the formation of twinning and twin intersections.The high stored strain energy at the regions of twins and twin intersections provided the driving force for TDRX.TDRX accelerated the grain refinement in the TiAl matrix near the Al_(2)O_(3)fiber.The present findings would provide a new perspective on DRX mechanisms,and provide the scientific guidance for optimizing the microstructures of TiAl matrix composites.展开更多
To improve the hit probability of tank at high speed,a prediction method of projectile-target intersection based on adaptive robust constraint-following control and interval uncertainty analysis is proposed.The method...To improve the hit probability of tank at high speed,a prediction method of projectile-target intersection based on adaptive robust constraint-following control and interval uncertainty analysis is proposed.The method proposed provides a novel way to predict the impact point of projectile for moving tank.First,bidirectional stability constraints and stability constraint-following error are constructed using the Udwadia-Kalaba theory,and an adaptive robust constraint-following controller is designed considering uncertainties.Second,the exterior ballistic ordinary differential equation with uncertainties is integrated into the controller,and the pointing control of stability system is extended to the impact-point control of projectile.Third,based on the interval uncertainty analysis method combining Chebyshev polynomial expansion and affine arithmetic,a prediction method of projectile-target intersection is proposed.Finally,the co-simulation experiment is performed by establishing the multi-body system dynamic model of tank and mathematical model of control system.The results demonstrate that the prediction method of projectile-target intersection based on uncertainty analysis can effectively decrease the uncertainties of system,improve the prediction accuracy,and increase the hit probability.The adaptive robust constraint-following control can effectively restrain the uncertainties caused by road excitation and model error.展开更多
This study investigated the formation mechanism of new grains due to twin–twin intersections in a coarse-grained Mg–6Al–3Sn–2Zn alloy during different strain rates of an isothermal compression.The results of elect...This study investigated the formation mechanism of new grains due to twin–twin intersections in a coarse-grained Mg–6Al–3Sn–2Zn alloy during different strain rates of an isothermal compression.The results of electron backscattered diffraction investigations showed that the activated twins were primarily{1012}tension twins,and 60°<1010>boundaries formed due to twin–twin intersections under different strain rates.Isolated twin variants with 60°<1010>boundaries transformed into new grains through lattice rotations at a low strain rate(0.01 s^(−1)).At a high strain rate(10 s^(−1)),the regions surrounded by subgrain boundaries through high-density dislocation arrangement and the 60°<1010>boundaries transformed into new grains via dynamic recrystallization.展开更多
Urban intersections without traffic signals are prone to accidents involving motor vehicles and pedestrians.Utilizing computer vision technology to detect pedestrians crossing the street can effectively mitigate the o...Urban intersections without traffic signals are prone to accidents involving motor vehicles and pedestrians.Utilizing computer vision technology to detect pedestrians crossing the street can effectively mitigate the occurrence of such accidents.Faced with the complex issue of pedestrian occlusion at signal-free intersections,this paper proposes a target detection model called Head feature And ENMS fusion Residual connection For CNN(HAERC).Specifically,the model includes a head feature module that detects occluded pedestrians by integrating their head features with the overall target.Additionally,to address the misselection caused by overlapping candidate boxes in two-stage target detection models,an Extended Non-Maximum Suppression classifier(ENMS)with expanded IoU thresholds is proposed.Finally,leveraging the CityPersons dataset and categorizing it into four classes based on occlusion levels(heavy,reasonable,partial,bare),the HAERC model is experimented on these classes and compared with baseline models.Experimental results demonstrate that HAERC achieves superior False Positives Per Image(FPPI)values of 46.64%,9.59%,9.43%,and 6.78%respectively for the four classes,outperforming all baseline models.The study concludes that the HAERC model effectively identifies occluded pedestrians in the complex environment of urban intersections without traffic signals,thereby enhancing safety for long-range driving at such intersections.展开更多
Understanding unsaturated flow behaviors in fractured rocks is essential for various applications.A fundamental process in this regard is flow splitting at fracture intersections.However,the impact of geometrical prop...Understanding unsaturated flow behaviors in fractured rocks is essential for various applications.A fundamental process in this regard is flow splitting at fracture intersections.However,the impact of geometrical properties of fracture intersections on flow splitting is still unclear.This work investigates the combined influence of geometry(intersection angle,fracture apertures,and inclination angle),liquid droplet length,inertia,and dynamic wetting properties on liquid splitting dynamics at fracture intersections.A theoretical model of liquid splitting is developed,considering the factors mentioned above,and numerically solved to predict the flow splitting behavior.The model is validated against carefullycontrolled visualized experiments.Our results reveal two distinct splitting behaviors,separated by a critical droplet length.These behaviors shift from a monotonic to a non-monotonic trend with decreasing inclination angle.A comprehensive analysis further clarifies the impacts of the key factors on the splitting ratio,which is defined as the percentage of liquid volume entering the branch fracture.The splitting ratio decreases with increasing inclination angle,indicating a decrease in the gravitational effect on the branch fracture,which is directly proportional to the intersection angle.A non-monotonic relationship exists between the splitting ratio and the aperture ratio of the branch fracture to the main fracture.The results show that as the intersection angle decreases,the splitting ratio increases.Additionally,the influence of dynamic contact angles decreases with increasing intersection angle.These findings enhance our understanding of the impact of geometry on flow dynamics at fracture intersections.The proposed model provides a foundation for simulating and predicting unsaturated flow in complex fractured networks.展开更多
Unsignalized intersections pose a challenge for autonomous vehicles that must decide how to navigate them safely and efficiently.This paper proposes a reinforcement learning(RL)method for autonomous vehicles to naviga...Unsignalized intersections pose a challenge for autonomous vehicles that must decide how to navigate them safely and efficiently.This paper proposes a reinforcement learning(RL)method for autonomous vehicles to navigate unsignalized intersections safely and efficiently.The method uses a semantic scene representation to handle variable numbers of vehicles and a universal reward function to facilitate stable learning.A collision risk function is designed to penalize unsafe actions and guide the agent to avoid them.A scalable policy optimization algorithm is introduced to improve data efficiency and safety for vehicle learning at intersections.The algorithm employs experience replay to overcome the on-policy limitation of proximal policy optimization and incorporates the collision risk constraint into the policy optimization problem.The proposed safe RL algorithm can balance the trade-off between vehicle traffic safety and policy learning efficiency.Simulated intersection scenarios with different traffic situations are used to test the algorithm and demonstrate its high success rates and low collision rates under different traffic conditions.The algorithm shows the potential of RL for enhancing the safety and reliability of autonomous driving systems at unsignalized intersections.展开更多
Let X={X(t)∈R^(d),t∈R^(N)}be a centered space-time anisotropic Gaussian field with indices H=(H_(1),…,H_(N))∈(0,1)~N,where the components X_(i)(i=1,…,d)of X are independent,and the canonical metric√(E(X_(i)(t)-X...Let X={X(t)∈R^(d),t∈R^(N)}be a centered space-time anisotropic Gaussian field with indices H=(H_(1),…,H_(N))∈(0,1)~N,where the components X_(i)(i=1,…,d)of X are independent,and the canonical metric√(E(X_(i)(t)-X_(i)(s))^(2))^(1/2)(i=1,…,d)is commensurate with■for s=(s_(1),…,s_(N)),t=(t_(1),…,t_(N))∈R~N,α_(i)∈(0,1],and with the continuous functionγ(·)satisfying certain conditions.First,the upper and lower bounds of the hitting probabilities of X can be derived from the corresponding generalized Hausdorff measure and capacity,which are based on the kernel functions depending explicitly onγ(·).Furthermore,the multiple intersections of the sample paths of two independent centered space-time anisotropic Gaussian fields with different distributions are considered.Our results extend the corresponding results for anisotropic Gaussian fields to a large class of space-time anisotropic Gaussian fields.展开更多
With the support of Vehicle-to-Everything(V2X)technology and computing power networks,the existing intersection traffic order is expected to benefit from efficiency improvements and energy savings by new schemes such ...With the support of Vehicle-to-Everything(V2X)technology and computing power networks,the existing intersection traffic order is expected to benefit from efficiency improvements and energy savings by new schemes such as de-signalization.How to effectively manage autonomous vehicles for traffic control with high throughput at unsignalized intersections while ensuring safety has been a research hotspot.This paper proposes a collision-free autonomous vehicle scheduling framework based on edge-cloud computing power networks for unsignalized intersections where the lanes entering the intersections are undirectional,and designs an efficient communication system and protocol.First,by analyzing the collision point occupation time,this paper formulates an absolute value programming problem.Second,this problem is solved with low complexity by the Edge Intelligence Optimal Entry Time(EI-OET)algorithm based on edge-cloud computing power support.Then,the communication system and protocol are designed for the proposed scheduling scheme to realize efficient and low-latency vehicular communications.Finally,simulation experiments compare the proposed scheduling framework with directional and traditional traffic light scheduling mechanisms,and the experimental results demonstrate its high efficiency,low latency,and low complexity.展开更多
In the next few years traffic will happen most of the time.This was triggered by the growing rate of vehicles against the road capacity which is not balance.All the time the congestion in the city of Semarang has been...In the next few years traffic will happen most of the time.This was triggered by the growing rate of vehicles against the road capacity which is not balance.All the time the congestion in the city of Semarang has been occurred at peak hours.Congestion also occurred in between Teuku Umar and Setia Budi road Jatingaleh because of a plot intersection(Kesatrian intersection,PLN intersection and Jatingaleh intersection)with the Toll Road.Jatingaleh is located in the southern city of Semarang which is a central meeting point between the upper and lower Semarang where the vehicle flows in through a combination of local current and regional traffic,and the flow of vehicles coming in and out from highway.The main cause of the problems that occurred in the area of Jatingaleh is due to the numbers of vehicles movement that occurs at the intersections.With the above issues,it is necessary to analyse the existing conditions and look into some solutions.Before carrying out an analysis a field surveys at peak hours for example morning(06:00 to 08:00 am)and for the afternoon(04:00 to 06:00 pm)should be conducted,then the number of vehicles is counted manually with“short-breakcounting”according to types of vehicles.From the analysis we found that the degree of saturation(DS)is 1.61 between Teuku Umar and Setia Budi road during the morning peak hours and 1.56 during the afternoon peak hours.This means that the capacity of the existing road is no longer able to accommodate the traffic flow.One of the solutions for the congestion that occurs at the intersection of Jatingaleh is to apply the efficiency of the intersection that is not in a plot with a Fly over,Underpass and the combination of Fly Over-Underpass.Base on the flow reduction calculation with 3 comparative modeling it shows that the Fly Over is the most technically efficient to be applied in this research.展开更多
智能网联技术的不断发展为实现公交信号优先提供了技术支持,也将助力智能网联公交向“精准公交”“安全公交”方向发展。本文从不同相位间的冲突博弈关系出发,构建智能网联环境下基于斗鸡博弈的公交信号优先引导策略。首先,利用斗鸡博弈...智能网联技术的不断发展为实现公交信号优先提供了技术支持,也将助力智能网联公交向“精准公交”“安全公交”方向发展。本文从不同相位间的冲突博弈关系出发,构建智能网联环境下基于斗鸡博弈的公交信号优先引导策略。首先,利用斗鸡博弈,分析以公交优先相位与非优先相位作为博弈双方的博弈行为,建立以加权延误为收益矩阵的博弈模型;其次,考虑优先公交车的准时性、最小绿灯时长限制、优先相位及非优先相位延误等因素,结合建立的博弈模型,采取主动优先与车速引导相结合的方法,提出智能网联环境下公交优先引导策略及优化流程;最后,利用SUMO(Simulation of Urban Mobility)和采集的交叉口数据对提出的优先引导策略进行仿真。结果表明:与初始配时相比,本文提出的公交信号优先策略可有效提高公交优先相位的通行效益,减少对非优先相位的负面影响;50%渗透率条件下,对比未实施策略,20%的优先公交车准点情况优化显著,平均排队长度、平均停车次数、延误等通行效益指标至少降低33.27%,油耗及CO_(2)排放至少降低12.20%;非优先相位各指标的劣化程度均低于8%。展开更多
文摘Background: Wrist pain is prevalent. Activities such as dexterous sports, prolonged use of personal handheld devices, and extensive desktop keyboard usage are common contributors to wrist pain. Intersection syndrome, a form of inflammatory tenosynovitis, occurs at the intersection of the first and second dorsal compartments of the wrist. The first dorsal compartment is comprised of the tendons of abductor pollicis longus and extensor pollicis brevis, while the second dorsal compartment contains the tendons of extensor carpi radialis longus and extensor carpi radialis brevis. Intersection syndrome is diagnosed by pain localized to the dorsoradial forearm, approximately five cm proximal to the wrist joint, which worsens with resisted wrist and thumb extension. To date, the use of hydro dissection with 5% dextrose under ultrasound guidance as a treatment for Intersection syndrome has not been reported. This case report presents the first report on ultrasound-guided hydro dissection as a therapeutic approach for intersection syndrome. Methods: A case report, with informed consent, involving a 32-year-old male athlete. The patient, a hurling player, presented with chronic right wrist pain diagnosed as intersection syndrome. The condition significantly affected his work, sporting activities, and daily living activities. Previous conservative management and physiotherapy had failed to alleviate his symptoms. To confirm the diagnosis, relevant imaging was performed, supplemented by dynamic ultrasound assessment. The procedure was performed aseptically. Continuous ultrasound guidance was employed to ensure accurate needle placement. Once the needle tip position was confirmed, an initial injection of 5 mL of 0.25% chirocaine was administered. 10 mL of 5% dextrose was injected under ultrasound guidance for hydro dissection, with good visualization of the solution’s distribution. Conclusion: Ultrasound-guided hydro dissection has not previously been documented as a treatment option for intersection syndrome. In this case, it proved to be an effective pain-relieving therapy with sustained effect at three-month clinical follow-up. Further studies are required.
基金Project(52204164)supported by the National Natural Science Foundation of ChinaProject(2021QNRC001)supported by the Young Elite Scientists Sponsorship Program by CAST,China。
文摘The intersection is a widely used traffic line structure from the shallow tunnel to the deep roadway,and determining the subsidence hidden danger area of the roof is the key to its stability control.However,applying traditional maximum equivalent span beam(MESB)theory to determine deformation range,peak point,and angle influence poses a challenge.Considering the overall structure of the intersection roof,the maximum equivalent triangular plate(METP)theory is proposed,and its geometric parameter calculation formula and deflection calculation formula are obtained.The application of the two theories in 18 models with different intersection angles,roadway types,and surrounding rock lithology is verified by numerical analysis.The results show that:1)The METP structure of the intersection roof established by the simulation results of each model successfully determined the location of the roof’s high displacement zone;2)The area comparison method of the METP theory can be reasonably explained:①The roof subsidence of the intersection decreases with the increase of the intersection angle;②The roof subsidence at the intersection of different roadway types has a rectangular type>arch type>circular type;③The roof subsidence of the intersection with weak surrounding rock is significantly larger than that of the intersection with hard surrounding rock.According to the application results of the two theories,the four advantages of the METP theory are compared and clarified in the basic assumptions,mechanical models,main viewpoints,and mechanism analysis.The large deformation inducement of the intersection roof is then explored.The J 2 peak area of the roof drives the large deformation of the area,the peak point of which is consistent with the center of gravity position of the METP.Furthermore,the change in the range of this peak is consistent with the change law of the METP’s area.Hence,this theory clarifies the large deformation area of the intersection roof,which provides a clear guiding basis for its initial support design,mid-term monitoring,and late local reinforcement.
基金funded by Sichuan International Studies University within the framework of the research project“Oulipian Experimentalism and Spatial Structure in the Travel Narratives of Jacques Roubaud”(sisu202008).
文摘This article explores the intersections of Buddhism,Daoism,and contemporary French literary practice in the study of the everyday(quotidien).Since the 1980s,French literature has increasingly shifted its focus from the exotic to the mundane,engaging with theoretical frameworks developed by scholars such as Henri Lefebvre and Michel de Certeau.Drawing on Buddhist notions of emptiness and dependent arising,as well as Daoist principles of yin-yang interdependence,the article bridges Eastern and Western philosophies to demonstrate the everyday not as a static or trivial backdrop,but as a dynamic and transformative space.It further examines how representations of daily life in the works of Georges Perec and Jacques Roubaud employ the meticulous documentation of mundane details to uncover hidden patterns,rhythms,and structures of human experience.Through literary fieldwork,Perec and Roubaud challenge conventional perceptions of the everyday,unveiling its depth,complexity,and potential for reinvention.
文摘In the next few years traffic will happen most of the time.This was triggered by the growing rate of vehicles against the road capacity which is not balance.All the time the congestion in the city of Semarang has occured at peak hours.Congestion also occured in between Teuku Umar and Setia Budi road Jatingaleh because of a plot intersection(Kesatrian intersection,PLN intersection and Jatingaleh intersection)with the Toll Road.Jatingaleh is located in the southern city of Semarang which is a central meeting point between the upper and lower Semarang where the vehicle flows in through a combination of local current and regional traffic,and the flow of vehicles coming in and out from highway.The main cause of the problems that occurred in the area of Jatingaleh is due to the numbers of vehicles movement that occurs at the intersections.With the above issues,it is necessary to analyse the existing conditions and look into some solutions.Before carrying out an analysis a field surveys at peak hours for example morning(06:00 to 08:00 am)and for the afternoon(04:00 to 06:00 pm)should be conducted,then the number of vehicles is counted manually with“short-breakcounting”according to types of vehicles.From the analysis we found that the degree of saturation(DS)is 1.61 between Teuku Umar and Setia Budi road during the morning peak hours and 1.56 during the afternoon peak hours.This means that the capacity of the existing road is no longer able to accommodate the traffic flow.One of the solutions for the congestion that occurs at the intersection of Jatingaleh is to apply the efficiency of the intersection that is not in a plot with a Fly over,Underpass and the combination of Fly Over-Underpass.Base on the flow reduction calculation with 3 comparative modeling it shows that the Fly Over is the most technically efficient to be applied in this research.
基金Supported by the Postgraduate Scientific Research Innovation Project of Hunan Province (CX20231033)。
文摘In this paper,we introduce the normalized L,mixed intersection body and demonstrate how the normalized L_(p) mixed intersection body operator can be used to obtain the polar body operator as a limit.Moreover,we study the L_(p)-Busemann-Petty type problem for the normalized L_(p) mixed intersection bodies.
基金the National Science and Technology Major Project(No.2019700160157)the Natural Science Foundation of Hunan Province(No.2021JJ40761)+3 种基金the Central South University Innovation-Driven Research Programmme(No.v2023CXQD030)the Independent Innovation Fund Project Aero Engine Corporation of China(No.CXPT-2021-001)the Postgraduate Scientific Research Innovation Project of Hunan Province(No.CX20230163)the Fundamental Research Funds for the Cen-tral Universities of Central South University(No.2023ZZTS0078)for providing financial support.
文摘Dynamic recrystallization(DRX)is of great significance for the thermomechanical processing and microstructural regulation of TiAl intermetallics.However,the underlying DRX mechanism remains poorly understood.In this study,an Avrami kinetics model for DRX was established,which was capable of predicting the DRX fraction accurately.In addition,the effect of Al_(2)O_(3)short fiber on the DRX mechanisms of TiAl matrix composite during the isothermal compression was investigated for the first time.The re-sults showed that other than inhibiting DRX by particles in the TiAl matrix composites,the addition of Al_(2)O_(3)short fiber accelerated a novel DRX process,which was induced by twinning and twin intersec-tions(TDRX).Thus,this composite exhibited a higher DRX rate than that of the as-cast TiAl monolithic alloy.The origin of the twin intersection and TDRX for the composite was revealed.The stress concentration near the Al_(2)O_(3)fiber was above the critical shear stress for twinning and thus was favorable for the formation of twinning and twin intersections.The high stored strain energy at the regions of twins and twin intersections provided the driving force for TDRX.TDRX accelerated the grain refinement in the TiAl matrix near the Al_(2)O_(3)fiber.The present findings would provide a new perspective on DRX mechanisms,and provide the scientific guidance for optimizing the microstructures of TiAl matrix composites.
基金financially supported by the National Natural Science Foundation of China(Grant 52175099)the China Postdoctoral Science Foundation(Grant No.2020M671494)+1 种基金the Jiangsu Planned Projects for Postdoctoral Research Funds(Grant No.2020Z179)the Nanjing University of Science and Technology Independent Research Program(Grant No.30920021105)。
文摘To improve the hit probability of tank at high speed,a prediction method of projectile-target intersection based on adaptive robust constraint-following control and interval uncertainty analysis is proposed.The method proposed provides a novel way to predict the impact point of projectile for moving tank.First,bidirectional stability constraints and stability constraint-following error are constructed using the Udwadia-Kalaba theory,and an adaptive robust constraint-following controller is designed considering uncertainties.Second,the exterior ballistic ordinary differential equation with uncertainties is integrated into the controller,and the pointing control of stability system is extended to the impact-point control of projectile.Third,based on the interval uncertainty analysis method combining Chebyshev polynomial expansion and affine arithmetic,a prediction method of projectile-target intersection is proposed.Finally,the co-simulation experiment is performed by establishing the multi-body system dynamic model of tank and mathematical model of control system.The results demonstrate that the prediction method of projectile-target intersection based on uncertainty analysis can effectively decrease the uncertainties of system,improve the prediction accuracy,and increase the hit probability.The adaptive robust constraint-following control can effectively restrain the uncertainties caused by road excitation and model error.
基金support from the Key Technology Research and Development Program of Shandong Province(Project No.2019GGX102060).
文摘This study investigated the formation mechanism of new grains due to twin–twin intersections in a coarse-grained Mg–6Al–3Sn–2Zn alloy during different strain rates of an isothermal compression.The results of electron backscattered diffraction investigations showed that the activated twins were primarily{1012}tension twins,and 60°<1010>boundaries formed due to twin–twin intersections under different strain rates.Isolated twin variants with 60°<1010>boundaries transformed into new grains through lattice rotations at a low strain rate(0.01 s^(−1)).At a high strain rate(10 s^(−1)),the regions surrounded by subgrain boundaries through high-density dislocation arrangement and the 60°<1010>boundaries transformed into new grains via dynamic recrystallization.
基金Beijing Natural Science Foundation(9234025)National Social Science Fund Project of China(21FGLB014)Humanity and Social Science Youth Foundation of Ministry of Education of China(21YJC630094).
文摘Urban intersections without traffic signals are prone to accidents involving motor vehicles and pedestrians.Utilizing computer vision technology to detect pedestrians crossing the street can effectively mitigate the occurrence of such accidents.Faced with the complex issue of pedestrian occlusion at signal-free intersections,this paper proposes a target detection model called Head feature And ENMS fusion Residual connection For CNN(HAERC).Specifically,the model includes a head feature module that detects occluded pedestrians by integrating their head features with the overall target.Additionally,to address the misselection caused by overlapping candidate boxes in two-stage target detection models,an Extended Non-Maximum Suppression classifier(ENMS)with expanded IoU thresholds is proposed.Finally,leveraging the CityPersons dataset and categorizing it into four classes based on occlusion levels(heavy,reasonable,partial,bare),the HAERC model is experimented on these classes and compared with baseline models.Experimental results demonstrate that HAERC achieves superior False Positives Per Image(FPPI)values of 46.64%,9.59%,9.43%,and 6.78%respectively for the four classes,outperforming all baseline models.The study concludes that the HAERC model effectively identifies occluded pedestrians in the complex environment of urban intersections without traffic signals,thereby enhancing safety for long-range driving at such intersections.
基金support from the National Natural Science Foundation of China (Grant No.52079062 and 42077177)the Natural Science Foundation of Jiangxi Province (Grant No.20232ACG01003)is acknowledged.
文摘Understanding unsaturated flow behaviors in fractured rocks is essential for various applications.A fundamental process in this regard is flow splitting at fracture intersections.However,the impact of geometrical properties of fracture intersections on flow splitting is still unclear.This work investigates the combined influence of geometry(intersection angle,fracture apertures,and inclination angle),liquid droplet length,inertia,and dynamic wetting properties on liquid splitting dynamics at fracture intersections.A theoretical model of liquid splitting is developed,considering the factors mentioned above,and numerically solved to predict the flow splitting behavior.The model is validated against carefullycontrolled visualized experiments.Our results reveal two distinct splitting behaviors,separated by a critical droplet length.These behaviors shift from a monotonic to a non-monotonic trend with decreasing inclination angle.A comprehensive analysis further clarifies the impacts of the key factors on the splitting ratio,which is defined as the percentage of liquid volume entering the branch fracture.The splitting ratio decreases with increasing inclination angle,indicating a decrease in the gravitational effect on the branch fracture,which is directly proportional to the intersection angle.A non-monotonic relationship exists between the splitting ratio and the aperture ratio of the branch fracture to the main fracture.The results show that as the intersection angle decreases,the splitting ratio increases.Additionally,the influence of dynamic contact angles decreases with increasing intersection angle.These findings enhance our understanding of the impact of geometry on flow dynamics at fracture intersections.The proposed model provides a foundation for simulating and predicting unsaturated flow in complex fractured networks.
基金supported by the National Natural Science Foundation of China (52102394,52172384)Hunan Provincial Natural Science Foundation of China (2023JJ10008)Young Elite Scientists Sponsorship Program by CAST (2022QNRC001)。
文摘Unsignalized intersections pose a challenge for autonomous vehicles that must decide how to navigate them safely and efficiently.This paper proposes a reinforcement learning(RL)method for autonomous vehicles to navigate unsignalized intersections safely and efficiently.The method uses a semantic scene representation to handle variable numbers of vehicles and a universal reward function to facilitate stable learning.A collision risk function is designed to penalize unsafe actions and guide the agent to avoid them.A scalable policy optimization algorithm is introduced to improve data efficiency and safety for vehicle learning at intersections.The algorithm employs experience replay to overcome the on-policy limitation of proximal policy optimization and incorporates the collision risk constraint into the policy optimization problem.The proposed safe RL algorithm can balance the trade-off between vehicle traffic safety and policy learning efficiency.Simulated intersection scenarios with different traffic situations are used to test the algorithm and demonstrate its high success rates and low collision rates under different traffic conditions.The algorithm shows the potential of RL for enhancing the safety and reliability of autonomous driving systems at unsignalized intersections.
基金supported by the National Natural Science Foundation of China(12371150,11971432)the Natural Science Foundation of Zhejiang Province(LY21G010003)+2 种基金the Management Project of"Digital+"Discipline Construction of Zhejiang Gongshang University(SZJ2022A012,SZJ2022B017)the Characteristic&Preponderant Discipline of Key Construction Universities in Zhejiang Province(Zhejiang Gongshang University-Statistics)the Scientific Research Projects of Universities in Anhui Province(2022AH050955)。
文摘Let X={X(t)∈R^(d),t∈R^(N)}be a centered space-time anisotropic Gaussian field with indices H=(H_(1),…,H_(N))∈(0,1)~N,where the components X_(i)(i=1,…,d)of X are independent,and the canonical metric√(E(X_(i)(t)-X_(i)(s))^(2))^(1/2)(i=1,…,d)is commensurate with■for s=(s_(1),…,s_(N)),t=(t_(1),…,t_(N))∈R~N,α_(i)∈(0,1],and with the continuous functionγ(·)satisfying certain conditions.First,the upper and lower bounds of the hitting probabilities of X can be derived from the corresponding generalized Hausdorff measure and capacity,which are based on the kernel functions depending explicitly onγ(·).Furthermore,the multiple intersections of the sample paths of two independent centered space-time anisotropic Gaussian fields with different distributions are considered.Our results extend the corresponding results for anisotropic Gaussian fields to a large class of space-time anisotropic Gaussian fields.
基金supported by the Natural Science Fund for Distinguished Young Scholars of Jiangsu Province under Grant BK20220067。
文摘With the support of Vehicle-to-Everything(V2X)technology and computing power networks,the existing intersection traffic order is expected to benefit from efficiency improvements and energy savings by new schemes such as de-signalization.How to effectively manage autonomous vehicles for traffic control with high throughput at unsignalized intersections while ensuring safety has been a research hotspot.This paper proposes a collision-free autonomous vehicle scheduling framework based on edge-cloud computing power networks for unsignalized intersections where the lanes entering the intersections are undirectional,and designs an efficient communication system and protocol.First,by analyzing the collision point occupation time,this paper formulates an absolute value programming problem.Second,this problem is solved with low complexity by the Edge Intelligence Optimal Entry Time(EI-OET)algorithm based on edge-cloud computing power support.Then,the communication system and protocol are designed for the proposed scheduling scheme to realize efficient and low-latency vehicular communications.Finally,simulation experiments compare the proposed scheduling framework with directional and traditional traffic light scheduling mechanisms,and the experimental results demonstrate its high efficiency,low latency,and low complexity.
文摘In the next few years traffic will happen most of the time.This was triggered by the growing rate of vehicles against the road capacity which is not balance.All the time the congestion in the city of Semarang has been occurred at peak hours.Congestion also occurred in between Teuku Umar and Setia Budi road Jatingaleh because of a plot intersection(Kesatrian intersection,PLN intersection and Jatingaleh intersection)with the Toll Road.Jatingaleh is located in the southern city of Semarang which is a central meeting point between the upper and lower Semarang where the vehicle flows in through a combination of local current and regional traffic,and the flow of vehicles coming in and out from highway.The main cause of the problems that occurred in the area of Jatingaleh is due to the numbers of vehicles movement that occurs at the intersections.With the above issues,it is necessary to analyse the existing conditions and look into some solutions.Before carrying out an analysis a field surveys at peak hours for example morning(06:00 to 08:00 am)and for the afternoon(04:00 to 06:00 pm)should be conducted,then the number of vehicles is counted manually with“short-breakcounting”according to types of vehicles.From the analysis we found that the degree of saturation(DS)is 1.61 between Teuku Umar and Setia Budi road during the morning peak hours and 1.56 during the afternoon peak hours.This means that the capacity of the existing road is no longer able to accommodate the traffic flow.One of the solutions for the congestion that occurs at the intersection of Jatingaleh is to apply the efficiency of the intersection that is not in a plot with a Fly over,Underpass and the combination of Fly Over-Underpass.Base on the flow reduction calculation with 3 comparative modeling it shows that the Fly Over is the most technically efficient to be applied in this research.
文摘智能网联技术的不断发展为实现公交信号优先提供了技术支持,也将助力智能网联公交向“精准公交”“安全公交”方向发展。本文从不同相位间的冲突博弈关系出发,构建智能网联环境下基于斗鸡博弈的公交信号优先引导策略。首先,利用斗鸡博弈,分析以公交优先相位与非优先相位作为博弈双方的博弈行为,建立以加权延误为收益矩阵的博弈模型;其次,考虑优先公交车的准时性、最小绿灯时长限制、优先相位及非优先相位延误等因素,结合建立的博弈模型,采取主动优先与车速引导相结合的方法,提出智能网联环境下公交优先引导策略及优化流程;最后,利用SUMO(Simulation of Urban Mobility)和采集的交叉口数据对提出的优先引导策略进行仿真。结果表明:与初始配时相比,本文提出的公交信号优先策略可有效提高公交优先相位的通行效益,减少对非优先相位的负面影响;50%渗透率条件下,对比未实施策略,20%的优先公交车准点情况优化显著,平均排队长度、平均停车次数、延误等通行效益指标至少降低33.27%,油耗及CO_(2)排放至少降低12.20%;非优先相位各指标的劣化程度均低于8%。
