A new methodology for incident detection and characterization on surface streets

In this paper, a new methodology is presented for real-time detection and characterization of incidents on surface streets. The proposed automatic incident detection approach is capable of detecting incidents promptly as well as characterizing incidents in terms of time-varying lane-changing fractions and queue lengths in blocked lanes, lanes blocked due to incidents, and incident duration. The architecture of the proposed incident detection approach consists of three sequential procedures: (1) Symptom Identification for identification of incident symptoms, (2) Signal Processing for real-time prediction of incident-related lane traffic characteristics and (3) Pattern Recognition for incident recognition. Lane traffic counts and occupancy are the only two major types of input data, which can be readily collected from point detectors. The primary techniques utilized in this paper include: (1) a discrete-time, nonlinear, stochastic system with boundary constraints to predict real-time lane-changing fractions and queue lengths and (2) a pattern-recognition-based algorithm employing modified sequential probability ratio tests (MSPRT) to detect incidents. Off-line tests based on simulated as well as video-based real data were conducted to assess the performance of the proposed algorithm. The test results have indicated the feasibility of achieving real-time incident detection using the proposed methodology.     

单层铺筑大厚度水泥碎石结构施工控制方法

文章以广西岑溪至梧州高速公路工程为例,介绍采用大吨位压路机,一次性摊铺碾压成型大厚度水泥碎石基层的施工流程,并通过对试验路段的钻芯取样实验,验证采用该施工方法的可行性.     

重大突发公共卫生事件下城市应急医疗物资优化调度研究

针对新型冠状病毒肺炎（新冠肺炎）疫情防控中应急医疗物资调度不尽合理、集配中心中转效率不够高等问题，重新设计了重大突发公共卫生事件下城市应急医疗物资调度与配送体系，并给出了应急医疗物资的分类方法。从医疗物资使用需求和库存估计可使用时间2个维度构建需求点紧急度指标，考虑突发公共卫生事件特征，以加权的需求满足率最大化为主要目标、车辆行驶距离最小化为次要目标，构建应急医疗物资动态分配模型，并通过算例验证了模型的有效性和可行性。结果表明：所构建的模型能够兼顾医疗物资分配的公平和效率，符合突发公共卫生事件中应急医疗物资供给和需求的动态变化特性，确保在物资短时间供给不足的情况下各需求点也能公平获取一定比例的物资；且模型仅要求各需求点上报各种品类医疗物资的使用人数和库存量，同时模型还给出数据缺失时的自动计算办法，可操作性更强；运用紧急度指标对需求满足率最大化目标进行校正，解决了各需求点因需求量差异对公平分配造成的影响，使得应急医疗物资分配更加合理。研究成果结合了新冠肺炎疫情防控中应急医疗物资调度的具体过程，使得分配模型更符合实际需要，可为城市应急医疗物资优化调度提供决策依据。     

Simulation of dynamic interaction between train and railway turnout

Dynamic train–track interaction is more complex in railway turnouts (switches and crossings) than that in ordinary tangent or curved tracks. Multiple contacts between wheel and rail are common, and severe impact loads with broad frequency contents are induced, when nominal wheel–rail contact conditions are disturbed because of the continuous variation in rail profiles and the discontinuities in the crossing panel. The absence of transition curves at the entry and exit of the turnout, and the cant deficiency, leads to large wheel–rail contact forces and passenger discomfort when the train is switching into the turnout track. Two alternative multibody system (MBS) models of dynamic interaction between train and a standard turnout design are developed. The first model is derived using a commercial MBS software. The second model is based on a multibody dynamics formulation, which may account for the structural flexibility of train and track components (based on finite element models and coordinate reduction methods). The variation in rail profile is accounted for by sampling the cross-section of each rail at several positions along the turnout. Contact between the back of the wheel flange and the check rail, when the wheelset is steered through the crossing, is considered. Good agreement in results from the two models is observed when the track model is taken as rigid.     

港口集装箱传送分配系统的分类比较研究

港口集装箱装卸传输的工作效率是码头竞争力的核心,在不同的码头条件下,只有采用合适的集装箱装卸传输系统才能使作业效率达到最佳。基于这个目标,分别以系统构成、效率、优劣点、适用条件为考核标准,对现今港口集装箱装卸传输进行传统系统和新型系统的横向比较及分析,为因地制宜地采用合适的集装箱传输系统提供理论依据。     

不同优化方法对斜拉桥成桥状态的影响分析探究

参考工程案例实用数据,借助有限元数理计算方式,基于零点移位法和最小屈曲应变能法,对斜拉索桥成桥状态数理计算开展专题分析探究。经过相关索力、弯矩及线形比对,分析了不同优化计算方法对该类型桥梁成桥状态的影响,以为同类斜拉索桥工程应用提供研究和技术参考,助力建设安全牢固的斜拉索桥梁。     

工程造价人员做好工程经济工作的新思路

工程造价控制是一项涉及立项、设计、施工、结算等内容的系统工程，采取的预防措施和控制手段应贯穿于工程项目建设的全过程。此文针对工程建设领域多年来存在的工程技术与经济分离的现象，从工程造价人员整体素质不高，在项目建设过程中参与的深度和广度不够，创新服务能力弱，急需改进和提高等方面进行分析与探讨，并提出工程造价人员要不断学习和掌握一定的工程技术，与设计人员密切配合，在提高编制概预算水平的基础上，向工程经济与技术相结合的模式发展，开创新理念的工作思路，这一思路可促使工程投资效益最大化。     

高职学生社会公德意识调查与分析

本文通过对高职学生社会公德意识现状的调查及数据分析,提出了优化高职学生公德意识的途径.     

多用途乘用车侧翻稳定性能动态测试方法研究

对比分析了国内外车辆侧翻稳定性相关的标准法规的基本情况。研究了车辆发生侧翻的类型和机理,基于侧向加速度判断车辆侧翻状态的方法,通过整车道路试验对比了正弦停滞试验和鱼钩试验诱导车辆发生侧翻的效果,初步探讨了多用途乘用车侧翻稳定性动态测试方法和评价指标,为国内车辆侧翻稳定系统的开发和测评标准的制定提供了参考。     

铁路大跨度连续梁拱组合桥结构参数研究

为了解结构设计参数对铁路大跨度连续梁-拱组合桥受力特性的影响,进而对今后同类桥梁设计提供引导作用,以兰渝线广元嘉陵江特大桥为工程背景,研究矢跨比、拱轴线形状、拱梁刚度比这3个设计参数对桥梁结构力学特性的影响。分析结果表明:矢跨比对拱肋轴力和拱脚、主梁中跨弯矩影响显著,取值在1/4~1/5时较为合理;1.6次抛物线、2.4次抛物线及圆弧线作为拱轴线时,拱脚截面弯矩过大,2次抛物线或悬链线作为此类桥型的拱轴线较为合理;拱梁刚度比对结构轴力影响较小,对拱肋弯矩影响较大,随拱梁刚度比的增大,拱肋分担的弯矩显著提高。