The prediction of projectile-target intersection for moving tank based on adaptive robust constraint-following control and interval uncertainty analysis

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.

Safe Efficient Policy Optimization Algorithm for Unsignalized Intersection Navigation

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.

{1012}twin–twin intersection-induced lattice rotation and dynamic recrystallization in Mg–6Al–3Sn–2Zn alloy

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.

MULTIPLE INTERSECTIONS OF SPACE-TIME ANISOTROPIC GAUSSIAN FIELDS

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.

Research of Fly over as a Solution to Congestion of Intersection Junction(Case Study:Jalan Jatingaleh Semarang)

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.

Proactive Platooning Based on C-V2X to Relieve Congestion at a Signalized Intersection

Nowadays urban traffic congestion becomes a major issue due to the increase in vehicles that lead to more commuting time,accidents,traffic violations,and high fuel consumption.Platooning is a good way to solve traffic congestion because it drives with a smaller inter-vehicle distance than human-driving.This paper proposes proactive platooning based on C-V2X(cellular vehicle-to-everything)to relieve congestion.Proactive platooning reduces the inter-vehicle distance and increases the throughput of signalized intersections through integrating the networked control platooning and computation-centralized platooning.Model and simulation experiments of proactive platooning were conducted to verify the impact of inter-vehicle distance on platooning latency,platooning safety,and traffic throughput.Simulation results show that the optimal inter-vehicle distance under proactive platooning is less than half of human-driving at a signalized intersection.

Automatic Lane-Level Intersection Map Generation using Low-Channel Roadside LiDAR

A lane-level intersection map is a cornerstone in high-definition(HD) traffic network maps for autonomous driving and high-precision intelligent transportation systems applications such as traffic management and control, and traffic accident evaluation and prevention. Mapping an HD intersection is time-consuming, labor-intensive, and expensive with conventional methods. In this paper, we used a low-channel roadside light detection and range sensor(LiDAR) to automatically and dynamically generate a lane-level intersection, including the signal phases, geometry, layout, and lane directions. First, a mathematical model was proposed to describe the topology and detail of a lane-level intersection. Second, continuous and discontinuous traffic object trajectories were extracted to identify the signal phases and times. Third, the layout, geometry, and lane direction were identified using the convex hull detection algorithm for trajectories. Fourth, a sliding window algorithm was presented to detect the lane marking and extract the lane, and the virtual lane connecting the inbound and outbound of the intersection were generated using the vehicle trajectories within the intersection and considering the traffic rules. In the field experiment, the mean absolute estimation error is 2 s for signal phase and time identification. The lane marking identification Precision and Recall are96% and 94.12%, respectively. Compared with the satellite-based,MMS-based, and crowdsourcing-based lane mapping methods,the average lane location deviation is 0.2 m and the update period is less than one hour by the proposed method with low-channel roadside LiDAR.

Novel Distance Measures on Hesitant Fuzzy Sets Based on Equal-Probability Transformation and Their Application in Decision Making on Intersection Traffic Control

The purpose of this study is to reduce the uncertainty in the calculation process on hesitant fuzzy sets(HFSs).The innovation of this study is to unify the cardinal numbers of hesitant fuzzy elements(HFEs)in a special way.Firstly,a probability density function is assigned for any given HFE.Thereafter,equal-probability transformation is introduced to transform HFEs with different cardinal numbers on the condition into the same probability density function.The characteristic of this transformation is that the higher the consistency of the membership degrees in HFEs,the higher the credibility of the mentioned membership degrees is,then,the bigger the probability density values for them are.According to this transformation technique,a set of novel distance measures on HFSs is provided.Finally,an illustrative example of intersection traffic control is introduced to show the usefulness of the given distance measures.The example also shows that this study is a good complement to operation theories on HFSs.

Six-year trends and intersectional correlates of meeting 24-Hour Movement Guidelines among South Korean adolescents:Korea Youth Risk Behavior Surveys,2013-2018

Background:Grounded in intersectionality theory,this study examined the 6-year prevalence trend and correlates in meeting Canada’s 24-Hour Movement Guidelines(Guidelines hereafter)in a nationally representative adolescent samples of South Korea(officially the Republic of Korea).Methods:Self-reported,annually repeated cross-sectional data collected between 2013 and 2018 were used(n=372,433,12-17 years old,47.9%females).Adolescents were categorized as meeting or not meeting different sets of physical activity,screen time(ST),and sleep recommendations within the Guidelines,separately for weekdays and weekend days.Intersectional correlates included sex and social class(i.e.,family economic status,parental education level,and academic performance).Multiple logistic regression analyses were performed.Results:Overall,the proportion of adolescents meeting physical activity,ST,and sleep recommendations were 5.3%,60.3%,and 10.2%on weekdays and 5.3%,28.2%,and 46.4%on weekend days,respectively.Between 2013 and 2018,no substantial changes were observed for meeting the physical activity or sleep recommendation,while meeting the ST recommendation was markedly lower in 2018.The proportion of meeting all 3 recommendations were 0.5%for weekdays and 0.8%for weekend days.Overall,compared to female adolescents,male adolescents were consistently associated with more favorable patterns of meeting different sets of recommendations,regardless of social class.Among females only,social class appeared to be not important or even detrimental in meeting different sets of recommendations.Being male,compounded with social class,was associated with meeting the ST recommendation.Conclusion:Less than 1%of Korean adolescents met the overall Guidelines.Intersectionality-based analysis and intervention may be important in promoting healthy active lifestyles among South Korean adolescents.

Mechanical analysis of the femoral neck dynamic intersection system with different nail angles and clinical applications

BACKGROUND The femoral neck dynamic intersection system(FNS)is mechanically more stable than other internal fixation techniques.Current studies have confirmed that the structural design of FNS has good biomechanical properties in European and American populations.However,whether the suitability of the FNS's 130°main nail angle design for Asian populations has been thoroughly investigated remains unclear.AIM To compare the biomechanical stability differences among different main nail angles of the FNS in the treatment of femoral neck fractures in Asian populations.METHODS Computed tomography data of the femur of healthy adult male volunteers were imported into Mimics software to create a three-dimensional model of the femur.The model was adapted to the curve using Geomagic software and imported into Solidworks software to construct the Pauwels I femoral neck fracture model and design the FNS internal fixation model using different main nail angles.Afterward,the models were assembled with the FNS fracture model and meshed using the preprocessing Hypermesh software.Subsequently,they were imported into Abaqus software to analyze and evaluate the biomechanical effects of different angles of the FNS main nail on the treatment of femoral neck fractures.RESULTS The peak displacement of the proximal femur under different angles of FNS fixation under stress was 7.446 millimeters in the 120°group and 7.416 millimeters in the 125°group;in the 130°,135°,and 140°FNS fixation groups,the peak displacement was 7.324 millimeters,8.138 millimeters,and 8.246 millimeters,respectively.In the 120°and 125°FNS fixation groups,the maximum stresses were concentrated at the main nail and the anti-rotation screw,which intersected the fracture line of the femur neck,resulting in peak stresses of 200.7 MPa and 138.8 MPa,respectively.Peak stresses of 208.8 MPa,219.8 MPa,and 239.3 MPa were observed on the angular locking plate distal to the locking screw in the 130°,135°,and 140°fixation groups.CONCLUSION FNS has significant stress distribution properties,a minimal proximal femoral displacement,and an optimal stability for treating femoral neck fractures in Asian populations when performed with a 130°main nail angle.

Law and Literature: Exploring the Intersection of Two Fields

This article aims to explore the intersection of law and literature,analyzing their connections and influences.First,the article introduces the definitions and basic characteristics of law and literature,emphasizing their similarities and differences.Then,the article discusses how literary works involve legal issues and how law becomes the subject and background of literary works.In addition,the article studies the interaction between law and literature,exploring the impact of novels on legal practice,and how legal texts are rewritten and interpreted in literary works.Finally,the article summarizes the relationship between law and literature and offers some prospects and reflections.

Analysis of Stopping Behavior at Rural T-Intersections Using Naturalistic Driving Study Data

Rural intersections account for around 30% of crashes in rural areas and 6% of all fatal crashes, representing a significant but poorly understood safety problem. Crashes at rural intersections are also problematic since high speeds on intersection approaches are present which can exacerbate the impact of a crash. Additionally, rural areas are often underserved with EMS services which can further contribute to negative crash outcomes. This paper describes an analysis of driver stopping behavior at rural T-intersections using the SHRP 2 Naturalistic Driving Study data. Type of stop was used as a safety surrogate measure using full/rolling stops compared to non-stops. Time series traces were obtained for 157 drivers at 87 unique intersections resulting in 1277 samples at the stop controlled approach for T-intersections. Roadway (i.e. number of lanes, presence of skew, speed limit, presence of stop bar or other traffic control devices), driver (age, gender, speeding), and environmental characteristics (time of day, presence of rain) were reduced and included as independent variables. Results of a logistic regression model indicated drivers were less likely to stop during the nighttime. However presence of intersection lighting increased the likelihood of full/rolling stops. Presence of intersection skew was shown to negatively impact stopping behavior. Additionally drivers who were traveling over the posted speed limit upstream of the intersection approach were less likely to stop at the approach stop sign.

The Pathologies of Modernity:Liberalism,Nihilism,Conservatism,Postmodernism,Intersectionality/Identity Politics,and Secular Humanism

In this article,Mocombe highlights what he calls the pathological-pathogenic purposive-rationalities(liberalism,nihilism,conservatism,postmodernism,intersectionality/identity politics,and secular humanism)that emerge out of modernity as constituted by the West under American hegemony.In the place of these pathological-pathogenic responses to the vagaries of modernity,Mocombe calls for an antihumanism,associated with what he calls libertarian communism,as a panacea to the aforementioned malaises.

Analysis of occupation time of vehicles at urban unsignalized intersections in non-lane-based mixed traffic conditions

In India, traffic flow on roads is highly mixed in nature with wide variations in the static and dynamic characteristics of vehicles. At unsignalized intersections, vehicles generally do not follow lane discipline and ignore the rules of priority. Drivers generally become more aggressive and tend to cross the uncontrolled intersections without considering the conflicting traffic. All these conditions cause a very complex traffic situation at unsignal- ized intersections which have a great impact on the capacity and performance of traffic intersections. A new method called additive conflict flow （ACF） method is suitable to determine the capacity of unsignalized inter- sections in non-lane-based mixed traffic conditions as prevailing in India. Occupation time is the key parameter for ACF method, which is defined as the time spent by a vehicle in the conflict area at the intersection. Data for this study were collected at two three-legged unsignalized intersections （one is uncontrolled and other one is semi- controlled） in Mangalore city, India using video-graphic technique during peak periods on three consecutive week days. The occupation time of vehicles at these intersections were studied and compared. The data on conflicting traffic volume and occupation time by each subject vehicle at the conflict area were extracted from the videos using image processing software. The subject vehicles were divided into three categories： two wheelers,cars, and auto-rickshaws. Mathematical relationships were developed to relate the occupation time of different cate- gories of vehicles with the conflicting flow of vehicles for various movements at both the intersections. It was found that occupation time increases with the increasing con- flicting traffic and observed to be higher at the uncontrolled intersection compared to the semicontrolled intersec- tion. The segregated turning movements and the presence of mini roundabout at the semicontrolled intersection reduces the conflicts of vehicular movements, which ulti- mately reduces the occupation time. The proposed methodology will be useful to determine the occupation time for various movements at unsignalized intersections. The models developed in the study can be used by practitioners and traffic engineers to estimate the capacity of unsignalized intersections in non-lane-based discipline and mixed traffic conditions.

Characteristics and risk of violation behavior of non-motorists at signalized intersections

Aiming at prevalent violations of non-motorists at urban intersections in China, this paper intends to clarify the characteristics and risks of non-motorist violations at signalized intersections through questionnaires and video recordings, which may serve as a basis for non-motorized vehicle management. It can help improve the traffic order and enhance the degree of safety at signalized intersections. To obtain the perception information, a questionaire survey on the Internet was conducted and 972 valid questionnaires were returned. It is found that academic degree contributes little to non-motorist violations, while electrical bicyclists have a relatively higher frequency of violations compared with bicyclists. The video data of 18 228 non-motorist behaviors indicate that the violation rate of all non-motorists is 26.5%; the number of conflicts reaches 1 938, among which violation conflicts account for 66.8%. The study shows that the violation rates and the violation behavior at three types of surveyed intersections are markedly different. It is also concluded that the conflict rates and the violation rates are positively correlated. Furthermore, signal violation, traveling in the wrong direction, and overspeeding to cross the intersection are the most dangerous among traffic violation behaviors.

NSGA-Ⅱ based traffic signal control optimization algorithm for over-saturated intersection group

In order to improve the efficiency of traffic signal control for an over-saturated intersection group, a nondominated sorting genetic algorithm Ⅱ（NSGA-Ⅱ） based traffic signal control optimization algorithm is proposed. The throughput maximum and average queue ratio minimum for the critical route of the intersection group are selected as the optimization objectives of the traffic signal control for the over-saturated condition. The consequences of the efficiency between traffic signal timing plans generated by the proposed algorithm and a commonly utilized signal timing optimization software Synchro are compared in a VISSIM signal control application programming interfaces （SCAPI） simulation environment by using real filed observed traffic data. The simulation results indicate that the signal timing plan generated by the proposed algorithm is more efficient in managing oversaturated flows at intersection groups, and, thus, it has the capability of optimizing signal timing under the over-saturated conditions.

Intersection capacity based on driver's visual characteristics

In order to reflect the influence of the drivers＇ characteristic differences on intersection capacity under a mixed traffic flow, a driver correction coefficient for the intersection capacity calculation according to the driver＇s visual characteristics is proposed. First, the parameters of the driver＇s visual characteristics at some real roads, including gaze fixation distribution, mean fixation duration, visual angle distribution and some other parameters at intersections, are collected. Then, the relationship between the traffic flow rate at intersections and the parameters of driver eye movements are established. The analytical results indicate that when the traffic flow is unsaturated, the parameters of driver eye movements change relatively little; however, when the traffic flow is saturated, the parameters of driver eye movements change drastically. Finally, the saturation-flow-rate model is modified according to the parameters of driver eye movements; thus, a capacity model of intersections considering the driver＇s visual characteristics is obtained.

改进后Ray-Box Intersection权系数矩阵的SART＋TVM重建算法

针对均匀采样稀疏型重建问题,研究了Ray-Box Intersection和传统的双线性插值两种权系数矩阵计算方法。对Ray-Box Intersection算法的逻辑漏洞进行了改进,利用直线生成法并结合射线斜率和像素位置关系提出了改进算法。该算法利用代数关系求得射线穿过重建区域的起点和终点,然后取不大于其坐标的最大整数,最后采用直线生成法,依据射线斜率沿X或Y方向得到该条射线在投影区域内经过的所有像素块的左下角坐标集合,对于每个像素块,射线与像素块交点距离即为该像素块对射线的加权值。实验结果表明,相比Ray-Box Intersection权系数矩阵算法,改进后算法速度提高了96%,最大峰值信噪比提高了19%;相比双线性插值算法,改进后算法收敛速度更快,在同样时间代价下最大峰值信噪比提高了5%。改进后的Ray-Box Intersection算法能够获得更好的重建图像质量,细节更清晰。

Method for pedestrian signal timing at signalized intersections

The pedestrian timing at signalized intersections is studied aiming at the problems of the inconsistency of the vehicular and pedestrian timing requirements and the insufficiency of pedestrian clearance. Based on the formulae of WALK and flashing DON＇T WALK （FDW） in the highway capacity manual （HCM）, the relationship between pedestrian signal indications and vehicular signal indications is discussed using the theory of traffic flow. Then, methods of pedestrian timing for different cases are established, particularly the methods of the pedestrian green adjustment. Ways of pedestrian crossing are analyzed for roadways with different forms and widths of the median island. The sampling values of calculation parameters are studied, and the recommended formulae of pedestrian timing for different conditions are presented.

Multi-phase signal setting and capacity of signalized intersection

A capacity model of multi-phase signalized intersections is derived by a stopping-line method. It is simplified with two normal situations： one situation involves one straight lane and one left-turn lane; the other situation involves two straight lanes and one left-turn lane. The results show that the capacity is mainly relative to signal cycle length, phase length, intersection layout and following time. With regard to the vehicles arrival rates, the optimal model is derived based on each phase＇s remaining time balance, and it is solved by Lagrange multipliers. Therefore, the calculation models of the optimal signal cycle length and phase lengths are derived and simplified. Compared to the existing models, the proposed model is more convenient and practical. Finally, a practical intersection is chosen and its signal cycles and phase lengths are calculated by the proposed model.