A model for the layout of bike stations in public bike‐sharing systems

The problem of designing a layout of bike stations for public bike‐sharing systems entails selecting a number of stations and then constructing them within a planning area having many bike traffic zones and candidate bike stations. In this paper, we proposed a mathematical model to formulate the layout of public bike stations with the objective of minimizing users' total travel time and investment budget constraints. The model can guarantee that the needs for picking up and dropping off bikes amidst all bike travel demands are satisfied. Using this model, the number and locations of bike stations and the number of bikes and parking lockers at each bike station can be simultaneously determined. A typical example solved by lingo solver is created to illustrate the proposed model. Copyright © 2015 John Wiley & Sons, Ltd.     

A self-learning system for local ramp metering with queue management

This paper presents the design and evaluation process of a self-learning system for local ramp metering control. This system is developed on the basis of reinforcement learning (RL) and can deal with the problem of on-ramp queue management through a continuous learning process. A general framework of the system design including the definition of RL elements and an algorithm that can accomplish the learning process is proposed. Simulation tests are carried out to evaluate the performance of the new system. In terms of the total time spent by road users, the new system can achieve a 30% reduction from the situation of no control, a result which is competitive with the widely accepted algorithm ALINEA. Meanwhile, simulation results show that the new system can keep on-ramp queues strictly under a series of pre-specified constraints, which proves its capability of managing on-ramp queues.     

宁德某一级渔港水域布置

相较于普通货运码头及船舶,渔港水域布置方式、渔船船型有着其特殊性。针对渔港水域布置中存在的要点、难点及问题,总结水运、水产行业标准及地方标准,对水域设计条件要求进行研究。根据数模结果,采用多个水域布置方案研究、分析及比选的方法,得到水域平面布置与数模结果间的规律。根据方案对比经验,综合考虑并取舍波浪、潮流、泥沙回淤因素,确定最优水域布置方式。     

悬挂式单轨交通线路设计

在从事贵州黔东南、成都大邑、陕西韩城等地多个悬挂式单轨交通项目的设计基础及实践经验上，对悬挂式单轨交通线路技术标准进行分析。通过理论计算，明确线路标准的数据及参数。对不同地段线路平面、纵断面设计方法进行总结，提出在路中、路侧、沿河及地下敷设等线路的布置形式。同时，对应着重考虑的因素，线路设计中的特殊问题以及优化设计的建议进行论述，提出在平面与纵断面组合设计时的注意事项，供业内人士在类似项目设计中参考。     

基于JACK的载人潜水器观察窗布局优化设计

为了提高载人潜水器人机工效设计的质量,有效考虑狭小工作舱下潜航员的生理舒适度,保证载人潜水器观察窗布局人机合理性。本文在载人潜水器载人舱的设计过程中应用了人机工效设计原理,利用JACK软件对载人潜水器载人舱观察窗布局进行仿真,对潜航员的工作姿态、舒适性、关节角度等进行模拟。首先将载人潜水器载人舱模型导入JACK人因分析软件中,采用第95百分位数的中国男性作为潜航员,对潜航员在载人舱内的工作姿态进行模拟,并对其进行工作姿势评估、快速上肢分析、舒适度评估、下背部分析。根据分析结果完成了相应的设计优化。     

Improving fuel consumption and CO2 emissions calculations in urban areas by coupling a dynamic micro traffic model with an instantaneous emissions model

Τhis study demonstrates the combination of a microscopic traffic simulator (AIMSUN) with an instantaneous emissions model (AVL CRUISE) to investigate the impact of traffic congestion on fuel consumption on an urban arterial road. The micro traffic model was enhanced by an improved car-following law according to Morello et al. (2014) and was calibrated to replicate measured driving patterns over an urban corridor in Turin, Italy, operating under adaptive urban traffic control (UTC). The method was implemented to study the impact of congestion on fuel consumption for the category of Euro 5 diesel <1.4 l passenger cars. Free flow and congested conditions led to respective consumption differences of −25.8% and 20.9% over normal traffic. COPERT 5 rather well predicted the impact of congestion but resulted to a much lower relative reduction in free flow conditions. Start and stop system was estimated to reduce consumption by 6% and 11.9% under normal and congested conditions, respectively. Using the same modelling approach, UTC was found to have a positive impact on CO₂ emissions of 8.1% and 4.5% for normal and congested conditions, respectively, considering the Turin vehicle fleet mix for the year 2013. Overall, the study demonstrates that the combination of detailed and validated micro traffic and emissions models offers a powerful combination to study traffic and powertrain impacts on greenhouse gas and fuel consumption of on road vehicles over a city network.     

城市多层次轨道交通体系功能布局规划研究——以深圳市为例

轨道交通功能布局规划确定轨道交通发展的基本框架,是轨道交通线网规划与发展协调决策的重要基础。实际规划中亟须加强对其重视程度及编制规范性。以城市与多层次轨道交通互动发展为主线,结合相关规范要求,提出轨道交通功能布局规划的基本思路,包含制定总体目标、构思联系走廊、拟出概念架构、协调层次布局、形成功能方案等五个方面。以深圳市为例,说明多层次轨道交通体系功能布局规划要点,归纳总结具有推广意义的轨道交通功能布局规划模式。     

重庆果园港总体设计

重庆果园港是具有代表意义的内河第三代综合性港口,具有规模大、承担运输货种多、环境影响因素复杂的特点。通过对果园港的规划定位、装卸工艺、码头结构形式、总平面布置等关键技术方案进行分析,介绍了设计过程的主要理念,总结了在新的形势下长江上游港口总体设计的要点,为同类型港口的设计工作提供参考借鉴。     

Efficient intersection control for minimally guided vehicles: A self-organised and decentralised approach

An important question for the practical applicability of the highly efficient traffic intersection control is about the minimal level of intelligence the vehicles need to have so as to move beyond the traffic light control. We propose an efficient intersection traffic control scheme without the traffic lights, that only requires a majority of vehicles on the road to be equipped with a simple driver assistance system. The algorithm of our scheme is completely decentralised, and takes into full account the non-linear interaction between the vehicles at high density. For vehicles approaching the intersection in different directions, our algorithm imposes simple interactions between vehicles around the intersection, by defining specific conditions on the real-time basis, for which the involved vehicles are required to briefly adjust their dynamics. This leads to a self-organised traffic flow that is safe, robust, and efficient. We also take into account of the driver comfort level and study its effect on the control efficiency. The scheme has low technological barrier, minimal impact on the conventional driving behaviour, and can coexist with the traffic light control. It also has the advantages of being easily scalable, and fully compatible with both the conventional road systems as well as the futuristic scenario in which driverless vehicles dominate the road. The mathematical formulation of our scheme permits large scale realistic numerical simulations of busy intersections, allowing a more complete evaluation of the control performance, instead of just the collision avoidance at the intersection.     

智能船舶中环境对WSN影响分析与优化对策

根据CCS《智能船舶规范》,分析了智能船舶WSN的应用特征及现状.根据电磁波传输理论,建立了"白盒"、"黑盒"、"窗口"、"反射"、"衍射"、"地面"6种静态组网模型;根据WSN应用,建立了"微微网"、"散射网"和"混合网"3种动态组网模型,系统地将整个船舶归纳为8种典型环境,并对此环境下智能船舶WSN节点的布局给予了优化方案.