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An Optimal Right-Turn Coordination System for Connected and Automated Vehicles at Urban Intersections
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作者 Mahmudul Hasan Shuji Doman +2 位作者 A.S.M.Bakibillah Md Abdus Samad Kamal Kou Yamada 《Computers, Materials & Continua》 2026年第1期430-446,共17页
Traffic at urban intersections frequently encounters unexpected obstructions,resulting in congestion due to uncooperative and priority-based driving behavior.This paper presents an optimal right-turn coordination syst... Traffic at urban intersections frequently encounters unexpected obstructions,resulting in congestion due to uncooperative and priority-based driving behavior.This paper presents an optimal right-turn coordination system for Connected and Automated Vehicles(CAVs)at single-lane intersections,particularly in the context of left-hand side driving on roads.The goal is to facilitate smooth right turns for certain vehicles without creating bottlenecks.We consider that all approaching vehicles share relevant information through vehicular communications.The Intersection Coordination Unit(ICU)processes this information and communicates the optimal crossing or turning times to the vehicles.The primary objective of this coordination is to minimize overall traffic delays,which also helps improve the fuel consumption of vehicles.By considering information from upcoming vehicles at the intersection,the coordination system solves an optimization problem to determine the best timing for executing right turns,ultimately minimizing the total delay for all vehicles.The proposed coordination system is evaluated at a typical urban intersection,and its performance is compared to traditional traffic systems.Numerical simulation results indicate that the proposed coordination system significantly enhances the average traffic speed and fuel consumption compared to the traditional traffic system in various scenarios. 展开更多
关键词 Right-turn coordination connected and automated vehicles vehicular communication edge processing urban intersection
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Reconceptualizing the Everyday in French Literary Fieldwork:Intersections of Buddhism,Daoism and French Literary Practice
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作者 ZHANG Dan 《Journal of Literature and Art Studies》 2025年第1期44-51,共8页
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
关键词 intersections EVERYDAY documentation literary fieldwork reinvention
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无信号灯控制交叉路口车-车交互场景基元库构建
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作者 胡林 陈旭东 +1 位作者 王兴华 杨非凡 《汽车工程》 北大核心 2026年第2期332-341,477,共11页
虚拟测试为自动驾驶系统的功能性和安全性评估与验证提供了一种强可控、低成本、高效的方案,但现有虚拟测试场景忽略了车辆速度与航向角等特征在交互过程中的描述,导致场景的真实性和覆盖度不足,降低了测试的可靠性。准确识别并表述车-... 虚拟测试为自动驾驶系统的功能性和安全性评估与验证提供了一种强可控、低成本、高效的方案,但现有虚拟测试场景忽略了车辆速度与航向角等特征在交互过程中的描述,导致场景的真实性和覆盖度不足,降低了测试的可靠性。准确识别并表述车-车交互过程的特征对于提升测试场景的真实性具有关键作用,因此本文基于inD数据集,构建了无信号灯控制交叉路口场景下车-车的交互场景基元库。首先,采用非参数贝叶斯模型对两车交互序列进行场景基元划分,并将场景基元表征的多维连续变量离散化为具备语义区分的分类变量;其次,通过独热编码和汉明距离构建距离矩阵,结合K-Medoids算法进行聚类分析,识别出25类具有不同运动特征的两车交互场景基元,系统揭示了真实交通环境中车-车交互行为的多样性。该交互场景基元库可进一步提高自动驾驶虚拟测试场景的真实性和多样性。 展开更多
关键词 无信号灯控制交叉路口 车-车交互 非参数贝叶斯 场景基元库
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Characteristics and risk of violation behavior of non-motorists at signalized intersections 被引量:6
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作者 赵星 任刚 +2 位作者 杜轩 王鹏 王卫杰 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期423-429,共7页
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 questionnaire... 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. 展开更多
关键词 traffic violation behavior traffic safety non- motorist signal intersection
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适用于轻量级客户端的多方隐私集合求交协议
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作者 杨乐 何慧阳 +2 位作者 尤玮婧 张佰韬 林璟锵 《信息网络安全》 北大核心 2026年第2期251-262,共12页
随着隐私保护需求的增长,多方隐私集合求交(MP-PSI)协议作为一种关键的隐私计算技术,在多个领域受到广泛关注。然而,在计算资源受限的环境中,现有的MP-PSI协议往往面临客户端计算负担较重的问题,限制了其在实际应用中的可行性。为解决... 随着隐私保护需求的增长,多方隐私集合求交(MP-PSI)协议作为一种关键的隐私计算技术,在多个领域受到广泛关注。然而,在计算资源受限的环境中,现有的MP-PSI协议往往面临客户端计算负担较重的问题,限制了其在实际应用中的可行性。为解决这一问题,文章提出一种基于布隆过滤器和同态加密的轻量级客户端MP-PSI协议。该协议通过引入不经意可编程伪随机函数,将大部分计算任务从客户端转移到服务器,从而显著降低了客户端的计算开销并充分利用了服务器的计算资源。实验结果表明,该协议在客户端计算时间和服务器计算效率方面均优于现有方案。协议在半诚实模型中可抵抗至多n-1个参与方合谋攻击,可确保诚实参与方的隐私。该协议为资源受限环境下的隐私保护问题提供了新的解决方案。 展开更多
关键词 多方隐私集合求交 轻量级客户端 布隆过滤器 不经意可编程伪随机函数
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基于改进协方差交叉融合算法的低空协同监视技术
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作者 张强 员腾蛟 林智奇 《科学技术与工程》 北大核心 2026年第2期841-847,共7页
为了满足未来智慧空中交通的发展对低空协同监视技术的迫切需求,提出了一种基于互协方差补偿机制的改进协方差交叉融合算法。该算法通过将互协方差信息引入传统协方差交叉(covariance intersection,CI)融合框架,有效降低了融合误差方差... 为了满足未来智慧空中交通的发展对低空协同监视技术的迫切需求,提出了一种基于互协方差补偿机制的改进协方差交叉融合算法。该算法通过将互协方差信息引入传统协方差交叉(covariance intersection,CI)融合框架,有效降低了融合误差方差阵估计的保守性。再结合无迹卡尔曼滤波(unscented Kalman filter,UKF)搭建双层滤波融合框架,融合了ADS-B、5G数据链和“北斗”短报文的监视数据。实验结果表明利用改进CI融合算法融合的航迹均方根误差在经纬度和高度上均有减小,证明了改进CI融合算法的有效性。这为目标跟踪、航迹预测等任务提供了更精准、更可靠的数据基础,有助于提升低空空域的安全性和运行效率。 展开更多
关键词 低空监视 无迹卡尔曼滤波 数据融合 协方差交叉融合算法
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Method for pedestrian signal timing at signalized intersections 被引量:3
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作者 王京元 王炜 《Journal of Southeast University(English Edition)》 EI CAS 2006年第4期564-569,共6页
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 ... 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. 展开更多
关键词 signalized intersection pedestrian signal timing WALK indication flashing DON'T WALK indication
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交叉口绿闪信号下行人过街行为特征分析与仿真建模
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作者 裴玉龙 赵金剑 《交通运输研究》 2026年第1期36-45,共10页
为研究交叉口绿闪信号期间行人过街行为特征,弥补现有行人仿真模型在此场景下的不足,首先基于无人机高空摄像采集的交叉口交通视频数据,采用Tracker影像分析软件提取行人轨迹与速度信息,对比分析了绿闪与常规绿灯信号下行人过街的速度... 为研究交叉口绿闪信号期间行人过街行为特征,弥补现有行人仿真模型在此场景下的不足,首先基于无人机高空摄像采集的交叉口交通视频数据,采用Tracker影像分析软件提取行人轨迹与速度信息,对比分析了绿闪与常规绿灯信号下行人过街的速度与避让行为特征。然后,结合实际数据改进传统社会力模型中的目标速度参数,构建了绿闪信号下的行人过街行为模型。最后,借助AnyLogic平台开展仿真实验,将仿真结果与实测行人过街速度进行对比。结果表明:绿闪时段行人平均步行速度为1.92 m/s,显著高于绿灯时期的1.48 m/s,部分行人以2.5~3.3 m/s的速度快速通过;绿闪时段行人在过街过程中普遍表现为“加速-减速-平稳”三阶段速度变化趋势;行人避让行为发生频率在绿闪场景下减少26.4%,避让触发距离平均延长1.22 m;行人避让横向偏移量保持在0.52 m左右,与绿灯时期无显著差异。仿真结果显示,模型速度曲线与实测数据拟合良好,平均模拟精度为95.2%,较已有相似场景研究的精度提高了6%。这表明改进后的模型能够较好地还原绿闪信号下行人过街的速度变化,可为信号交叉口行人仿真提供参考。 展开更多
关键词 城市交通 行人过街特性 社会力模型 信号交叉口 行人绿闪信号
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Ultrafast Dynamics Through Conical Intersections in 2,6-dimethylpyridine Studied with Time-resolved Photoelectron Imaging
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作者 邱学军 朱荣淑 +3 位作者 徐晏琪 布玛利亚·阿布力米提 张嵩 张冰 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第5期551-556,I0003,共7页
The ultrafast dynamics through conical intersections in 2,6-dimethylpyridine has been studied by femtosecond time-resolved photoelectron imaging coupled with time-resolved mass spectroscopy. Upon absorption of 266 nm ... The ultrafast dynamics through conical intersections in 2,6-dimethylpyridine has been studied by femtosecond time-resolved photoelectron imaging coupled with time-resolved mass spectroscopy. Upon absorption of 266 nm pump laser, 2,6-dimethylpyridine is excited to the S2 state with a ππ character from So state. The time evolution of the parent ion signals consists of two exponential decays. One is a fast component on a timescale of 635 fs and the other is a slow component with a timescale of 4.37 ps. Time-dependent photo- electron angular distributions and energy-resolved photoelectron spectroscopy are extracted from time-resolved photoelectron imaging and provide the evolutive information of S2 state. In brief, the ultrafast component is a population transfer from S2 to S1 through the S2/S1 conical intersections, the slow component is attributed to simultaneous IC from the S2 state and the higher vibrational levels of S1 state to So state, which involves the coupling of S2/S0 and S1/So conical intersections. Additionally, the observed ultrafast S2--+S1 transition occurs only with an 18% branching ratio. 展开更多
关键词 2 6-dimethylpyridine Photoelectron imaging Conical intersection Internalconversion Time-resolved spectroscopy
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Multi-phase bus signal priority strategy at isolated intersections
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作者 王琳虹 别一鸣 +1 位作者 王殿海 宋现敏 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期430-435,共6页
To satisfy the multiple priority requests from buses that arrive at different phases within a small time window, a multi-phase bus signal priority (MPBSP) strategy is developed. The proximity principle is brought fo... To satisfy the multiple priority requests from buses that arrive at different phases within a small time window, a multi-phase bus signal priority (MPBSP) strategy is developed. The proximity principle is brought forward to settle the conflicts among multiple priority requests and arrange the optimal priority sequence. To avoid over saturation of the intersection, a conditional MPBSP algorithm that adopts early green and green extension strategies is developed to give priority to the bus with the highest priority level when green time that each phase runs makes its saturation degree not larger than 0. 95. Finally, the algorithm is tested in the VISSIM environment and compared with the normal signal timing algorithm. Sensitive analysis of the number of priority phases, bus demand, and volume to capacity ratios are conducted to quantify their impacts on the benefits of the MPBSP. Results show that the MPBSP strategy can effectively reduce bus delays, and with the increase in the number of priority phases, the reduction range of bus delays also increases. 展开更多
关键词 bus signal priority multiple phases early green green extension isolated intersection
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Analytical method of minimum spacing of signalized intersections on bidirectional two-lane highways
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作者 马永锋 袁黎 张文波 《Journal of Southeast University(English Edition)》 EI CAS 2015年第4期547-552,共6页
In order to improve the smoothness of traffic flow on bidirectional two-lane highways, an analytical method is proposed to optimize the minimum spacing of the signalized intersections. The minimum signal spacing is de... In order to improve the smoothness of traffic flow on bidirectional two-lane highways, an analytical method is proposed to optimize the minimum spacing of the signalized intersections. The minimum signal spacing is determined by two parts, including the necessary distance for stabilizing the traffic flow after it passes through the signalized intersections and the length of the upstream functional area of intersection. For the former, based on the platoon dispersion theory, the stable distance determination problem of traffic flow is studied and a model of dispersion degrees varying with the distance from the upstream intersection is presented, in which the time headway is intended to yield the shifted negative exponential distribution. The parameters of the model for medal and collector highways are estimated respectively based on the field data. Then, the section at which the slope of dispersion degree curve equals -0.1 is regarded as the beginning of the dispersion stable state. The length of the intersection upstream functional area is determined by three parts, including the distance traveled during perception-reaction time, the distance traveled while a driver decelerates to a stop, and the queue storage length. Based on the above procedures, the minimum signal spacing of each highway category is proposed. 展开更多
关键词 HIGHWAY signalized intersection SPACING platoon dispersion
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THE MAXIMUM NUMBER OF INTERSECTIONS BETWEEN TWO PLANE RECTANGULAR PATHS
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作者 LI QIAO, XU JUNMING, AND ZHANG ZHONGLIANG 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1995年第2期215-222,共8页
We show that the maximum number of intersections between two plane rectangular paths with lengths m and(mod 3); and it is mn+1 otherwise.
关键词 Lay-out on printed circuit board rectangular paths intersections.
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Safety Analysis for Older Drivers at SignalizedIntersections
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作者 Daba S. Gedafa 《Journal of Civil Engineering and Architecture》 2013年第5期626-632,共7页
The proportions of older drivers continue to increase since baby boom generation is becoming old. The level of mobility of older drivers is also increasing. Older drivers begin to noticeably be over-involved in fatal ... The proportions of older drivers continue to increase since baby boom generation is becoming old. The level of mobility of older drivers is also increasing. Older drivers begin to noticeably be over-involved in fatal crashes. Intersections appear to be hazardous to older drivers, particularly left turn due to one or more of. sensory, perceptual, cognitive, physical and general driving knowledge deficiencies. The safety concern of older drivers is also becoming significant. Ten years of crash data has been extracted from Kansas accident report system. It has been analyzed using SAS (statistical analysis system) software. Five different age groups have been considered. Comparison has been made between different age groups of the same gender, and the same age group for different gender. Effects of light condition, weather condition, surface type, surface condition, road character and construction/maintenance zone on older drivers' safety have also been considered in this study. It has been found out that proportion of older drivers in through movement involved in accident decreases as age increases whereas the proportion of left turn accidents increases with age, left turn is harder for females in all age groups, and proportion of right turn accidents has no specific trend. Most of the accidents have taken place during daylight when there are no adverse weather conditions on dry surface, straight and level road, and blacktop surface type. 展开更多
关键词 Traffic safety older drivers intersections.
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基于旋转单天线的欺骗干扰检测方法
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作者 陈世淼 倪淑燕 +2 位作者 王绍山 王海宁 吕金飞 《北京航空航天大学学报》 北大核心 2026年第1期244-251,共8页
欺骗干扰具有隐蔽性强、危害性大的特点,严重威胁全球导航卫星系统(GNSS)的安全稳定运行。目前基于运动单天线的欺骗干扰检测方法无法实现多来向欺骗干扰检测。为此,提出一种用于旋转单天线的基于波达方向角度差的欺骗干扰检测方法。该... 欺骗干扰具有隐蔽性强、危害性大的特点,严重威胁全球导航卫星系统(GNSS)的安全稳定运行。目前基于运动单天线的欺骗干扰检测方法无法实现多来向欺骗干扰检测。为此,提出一种用于旋转单天线的基于波达方向角度差的欺骗干扰检测方法。该方法的本质是根据接收信号的载波相位估计一对信号之间的波达方向角度差。当没有欺骗信号时,波达方向角度差的估计值应与预测值一致。欺骗信号难以精确模拟导航信号的方向性,会破坏波达方向角度差的估计值和预测值一致性。因此,基于波达方向角度差的估计值和预测值建立检测变量,通过广义似然比检验(GLRT)可以检测多来向欺骗信号。进行软件仿真分析旋转单天线的参数对检测性能的影响,并通过现场试验进行验证和评估。结果表明:所提方法可高效实现多来向欺骗干扰的检测。 展开更多
关键词 欺骗干扰检测 载波相位 波达方向 角度差 旋转天线
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开角范围约束下分布式无源声呐网络多目标跟踪方法
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作者 郑策 王一名 +2 位作者 孙思博 乔钢 吴罗柽 《声学学报》 北大核心 2026年第2期574-591,共18页
针对开角约束条件下分布式无源声呐网络的多目标跟踪问题,提出一种基于广义协方差交叉融合的标签多伯努利跟踪方法。通过划分全局开角覆盖范围,将各节点的多目标后验密度分解为重叠区域和非重叠区域部分,并推导出融合后多目标后验密度... 针对开角约束条件下分布式无源声呐网络的多目标跟踪问题,提出一种基于广义协方差交叉融合的标签多伯努利跟踪方法。通过划分全局开角覆盖范围,将各节点的多目标后验密度分解为重叠区域和非重叠区域部分,并推导出融合后多目标后验密度的解析表达式;进一步改进了基于广义协方差交叉散度的批次匹配方法,无需邻节点开角范围的先验信息,有效解决了节点间批次缺失和不一致问题。仿真实验结果表明,该方法实现了不同开角覆盖范围场景下各个节点目标信息的融合,有效提升了目标跟踪精度和稳定性。SwellEx-96海试数据处理结果进一步表明,通过约束声呐节点的有效开角范围,可以避免端射方向观测精度下降对融合性能的影响。 展开更多
关键词 分布式系统 无源声呐 多目标跟踪 广义协方差交叉
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基于微观换道的互通入口与平交进口最小净距研究
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作者 陈桥梁 潘兵宏 田鑫 《公路交通科技》 北大核心 2026年第1期33-47,共15页
【目标】在集散型一级公路中,互通式立体交叉入口与平面交叉进口间距设置不合理易导致交通受扰、冲突增加等潜在安全风险,目前对此尚无明确规定。为解决这一问题,本研究构建了可量化的最小净距模型,并提出工程可行的净距推荐值。【方法... 【目标】在集散型一级公路中,互通式立体交叉入口与平面交叉进口间距设置不合理易导致交通受扰、冲突增加等潜在安全风险,目前对此尚无明确规定。为解决这一问题,本研究构建了可量化的最小净距模型,并提出工程可行的净距推荐值。【方法】首先,从互通入口和平交进口功能独立性出发,界定不同加速车道形式下的最小净距范围。随后,基于驾驶人在最不利情况下的行驶特性和驾驶习惯,建立了由恢复距离、交通标志判读距离、换道距离和驶出确认距离构成的最小净距计算模型,并通过数据调查,确定了计算模型中关键参数的取值,计算了最小净距理论建议值。最后,采用VISSIM仿真软件构建互通入口与平交进口路段仿真模型,采用冲突率作为评价指标,分析了不同交通量对应的最小净距推荐值,验证了理论最小净距值的合理性。【结果】主线单向3车道情况下,设计速度为60 km/h和80 km/h时的互通入口与平交进口最小净距一般值分别为680 m和880 m;最小净距值受交通量影响较大,随v/C值的提高而增加。【结论】本研究所构建模型能有效反映互通入口和平交进口的空间需求,提出的最小净距具有良好的工程适用性,可为集散型一级公路的设计提供依据。 展开更多
关键词 智能交通 最小净距 VISSIM仿真 互通式立交 平面交叉 集散型一级公路
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一种基于不规则三角网的精确求交方法及三维地质建模应用
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作者 李逸达 朱双 郑贵洲 《地质科技通报》 北大核心 2026年第1期351-359,共9页
针对目前三维地质模型求交方法中精确度不高、数值计算存在误差等问题,提出一种基于不规则三角网、融合浮点精度与精确精度的地质体精确求交算法。首先,构建不规则三角网(TIN)的方向包围盒(OBB)层次树,通过快速碰撞检测筛选出有效相交... 针对目前三维地质模型求交方法中精确度不高、数值计算存在误差等问题,提出一种基于不规则三角网、融合浮点精度与精确精度的地质体精确求交算法。首先,构建不规则三角网(TIN)的方向包围盒(OBB)层次树,通过快速碰撞检测筛选出有效相交三角形对集合,大幅缩减后续计算范围。其次,将相交三角形对分解为边−三角形求交单元,建立包含交点空间位置状态(onVertex(顶点上);onEdge(边上);inTriangle(面内))及对应实体(点、边、面)ID的交点位置关系结构,既消除交点坐标的冗余计算,又通过位置状态与实体ID匹配精准判别重复交点(如:onVertex状态下匹配顶点ID;onEdge状态下匹配边ID)。最后,根据拓扑正确性需求动态选择精度模式:若浮点精度可维持拓扑正确,则采用投影降维的约束Delaunay三角化(CDT)方法完成重三角化;若出现交点位置偏移(如面内点投影至边外)、点重合或交线段虚假相交等偏差,则切换至有理数表示的精确精度,通过约束点插入(面内点将三角形拆分为3个新三角、边上点将相邻三角形拆分为4个新三角)与约束线段插入(处理相交线段并执行边交换规则:凸四边形直接换边、凹四边形待排队换边)实现重三角化,确保重构结果的拓扑一致性。结果表明,提出的求交算法可以很好地支撑三角网的求交运算,算法转换至精确精度的次数少,具有较好的计算效率及较高的鲁棒性。算法平均时间花销优于GOCAD软件,能够满足大多数不规则三角网复杂地质模型间求交计算的需要。 展开更多
关键词 地质体 三维地质建模 不规则三角网 三角网求交 重三角化
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深煤层弱固结面与水力裂缝相交扩展规律研究
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作者 徐敏 孔祥伟 +4 位作者 陈青 谢昕 张少斌 谢广宇 徐洲 《煤矿安全》 北大核心 2026年第1期1-10,共10页
煤岩储层内发育大量的割理、层理、天然裂缝等弱固结面,孔隙结构复杂,导致水力压裂期间裂缝扩展形态难以预测。明确煤层弱固结面与水力裂缝相交扩展规律,有利于实现煤层压裂全面有效增渗。基于黏聚力单元法,考虑弱固结面的产状以及与射... 煤岩储层内发育大量的割理、层理、天然裂缝等弱固结面,孔隙结构复杂,导致水力压裂期间裂缝扩展形态难以预测。明确煤层弱固结面与水力裂缝相交扩展规律,有利于实现煤层压裂全面有效增渗。基于黏聚力单元法,考虑弱固结面的产状以及与射孔的间距,建立了弱固结面水力压裂裂缝扩展模型,分析了不同弱固结面逼近角和强度下,长距比(弱固结面长度与注入点到弱固结面中心点间距的比值)对水力裂缝相交扩展规律的影响。结果表明:当长距比为1/3、2/3、1/1时,随逼近角增大,裂缝偏转角也增大;当长距比为1/3、2/3时,随逼近角增大,总缝长逐渐减小;当长距比为1/1时,随逼近角增大,总缝长逐渐增大;当逼近角≤15°时,水力裂缝与弱固结面相交后更倾向于沿弱固结面方向扩展延伸;当逼近角≥30°时,水力裂缝容易穿透弱固结面;当逼近角为30°时,缝宽最大;当弱固结面强度增大时,裂缝的偏转角和改造长度均呈增大趋势。 展开更多
关键词 煤层压裂 黏聚力单元 裂缝相交 弱固结面 长距比
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位移型两相位交叉口设计方法及验证——以T型交叉口为例
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作者 申振武 邓帅 +2 位作者 王敏 李波 李晓宇 《公路交通科技》 北大核心 2026年第2期10-18,共9页
【目标】为突破传统交叉口优化研究的瓶颈,提升T形交叉口的通行效率并缓解交通拥堵,提出了一种新型的位移型两相位的交叉口优化设计方法。【方法】首先,系统性地提出了位移型两相位交叉口的概念,并将其物理结构归纳为单点位移、两点位... 【目标】为突破传统交叉口优化研究的瓶颈,提升T形交叉口的通行效率并缓解交通拥堵,提出了一种新型的位移型两相位的交叉口优化设计方法。【方法】首先,系统性地提出了位移型两相位交叉口的概念,并将其物理结构归纳为单点位移、两点位移和三点位移3大类共7种基本形式;其次,在信号配时方面,设计了直行同步与直行异步2种方法,并详细分析了快慢交通对应的组织策略;最后,为验证方案的有效性,选取了武汉市某T形交叉口作为实际案例,通过实地交通调查获取数据,并利用VISSIM仿真软件分别构建了现状模型与位移两相位优化方案模型。通过对比仿真结果,提取了交叉口整体服务水平、车辆平均延误及最大排队长度等关键评价指标。【结果】仿真结果显示,优化方案效果显著:交叉口的整体服务水平大幅提升;车辆平均延误时间由83.61 s降至22.23 s;最大排队长度也从510 m缩短至100 m。这些量化数据充分证明了位移型设计在提升通行效率方面的巨大潜力。【结论】位移型两相位交叉口能够针对性地缓解传统控制模式下的拥堵问题,有效改善交叉口运行状况。该研究成果为城市交通拥堵治理提供了一种创新且可行的设计方法,具有实际应用和推广的价值。 展开更多
关键词 智能交通 位移型两相位交叉口 交叉口冲突理论 T型交叉口 交通组织 VISSIM仿真
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综采工作面连续过交叉空巷充填控制技术研究与应用
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作者 曹海岗 姜全乐 +1 位作者 陈聪 邵泽宇 《中国矿业》 北大核心 2026年第2期218-228,共11页
针对综采工作面连续过交叉空巷问题,以西部某矿新布置综采面前方连续出现交叉空巷工况为研究背景,采用理论分析、数值模拟和现场试验等方法,对空巷直接顶的力学分析、空巷的围岩稳定性进行了研究,确定了空巷充填稳定控制采场覆岩技术,... 针对综采工作面连续过交叉空巷问题,以西部某矿新布置综采面前方连续出现交叉空巷工况为研究背景,采用理论分析、数值模拟和现场试验等方法,对空巷直接顶的力学分析、空巷的围岩稳定性进行了研究,确定了空巷充填稳定控制采场覆岩技术,研究优化了充填体参数,进行了现场试验验证。研究结果表明:通过建立局部充填下空巷直接顶力学模型,该空巷充填体的最佳长度间距为6 m,空巷临界支护阻力随着巷道宽度的增加而增加;根据对平行空巷布置不同长度的充填体情况下的塑性区分布规律、围岩破坏与围岩应力情况的数值模拟可知,随着充填体长度的增加,各种表征巷道围岩变形的指标均呈下降趋势,10 m充填长度下工作面推至空巷时顶板下沉量、充填体工作面侧巷帮移进量、底鼓量和远离工作面侧巷帮变形量相较于6 m充填体分别减少了22%、17%、4%和24%;空巷充填体长度的改变,会使塑性区的范围也随之变化,空巷充填体长度越大,空巷周围塑性区的范围越小。本次现场工业性试验验证了局部充填方案的可靠性。 展开更多
关键词 交叉空巷 围岩变形 充填控制技术 数值模拟 综采工作面
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