Auction-based highway reservation system an agent-based simulation study

Based on previous studies of a highway reservation system, this paper proposed an auction-based implementation, in which the users can bid for the right to use a route during a certain period of time. This paper models the auction system with MATSim using an agent-based simulation technique. The agents adopt their own bidding logic in the auction, and the price converges after around 130 iterations, when the number of users using the reserved highway and the total collected revenue become stable. When the overall demand changes, the collected revenue ranges from 5 to 11 dollars per user, and from 0.7 to 1.5 dollars per mile. The auction system can transfer more consumer surplus to the toll road operators, since it is a personalized tolling mechanism. The users are using the reservation system as insurance of a guaranteed congestion-free travel. The auction-based highway reservation shows great potential as a new traffic management system.     

Collecting a multi-dimensional three-weeks household time-use and activity diary in the Bandung Metropolitan Area,Indonesia

This paper describes a comprehensive panel data collection and analysis at household level, including detailed travel behaviour variables and comprehensive in-home and out-of-home activities, individual cognitive habits and affective behaviours, the rate of physical activity, as well as health related quality of life (QoL) information in the Bandung Metropolitan Area (BMA) of Indonesia. To our knowledge, this is the first attempt to collect an individual’s activity diary over an extended period as it captures the multi-tasking activities and multidisciplinary factors that underlie individual activity-travel patterns in a developing country. Preliminary analyses of the collected data indicate that different beliefs, anticipated emotions, support and attachment to motorised modes significantly correlate with different groups of occupation, gender, age, activity participation, multi-tasking activities, and physical health, but not with different social and mental health. This finding highlights the reason why implementing car reduction policies in Indonesia, without breaking or changing the individual’s habits and influencing his/her attitudes have not been fruitful. The results also show that endorsing more physical activities may result in a significant reduction in the individual’s motorised mode use, whilst individuals who demonstrate a tendency to use their spare time on social activities tend to have better social health conditions. Furthermore, undertaking multi-tasking out-of-home discretionary activities positively correlates with better physical health. All these highlight the importance of properly understanding and analysing the complex mechanisms that underlie these fundamental factors that shape individual daily activity-travel patterns in developing countries. This type of multidisciplinary approach is needed to design better transport policies that will not only promote better transport conditions, but also a healthier society with a better quality of life.     

高速铁路桥台台背土压力试验与空间土压力计算分析

高速铁路桥台台后填土从填料选择、施工控制、质量监测等方面均不同于常规铁路。结合试验工程对台背土压力进行研究,同时运用三维有限元程序进行模拟计算,并将计算结果与实测结果进行对比分析。现场测试结果表明,台背土压力大致呈“抛物线型”分布,与库仑土压力理论的线性分布不同。软土地基上桥台土压力存在一定的时间效应,填土结束后有一随时间增长而逐渐趋于稳定的过程,至最终稳定大致需要3个月时间。有限元分析结果表明,台背土压力分布存在一定的空间效应,在同一深度上数值并不相等,中间大,两侧小。用库仑公式计算的结果比数值计算与实测的结果偏于安全。     

船舶电网参数基于DSP的液晶显示的研究

根据点阵液晶显示模块SED1335在船舶电网参数检测中的应用,提出了一种控制液晶显示的实现方法。针对液晶显示控制系统中遇到的大量数据的实时高速传输问题,采用具有快速的计算能力和强大的信息处理能力的数字信号处理器。具体介绍了数字处理芯片TMS320F2812及液晶模块SED1335的功能特性和控制参数,并提出以TMS320F2812为控制核心的硬件电路,给出了C语言实现软件设计的具体方法。     

The variation in the value of travel-time savings and the dilemma of high-speed rail in China

This paper examines the variation in the value of travel-time savings (VTTS), a fundamental element determining the market demand for high-speed rail. Following a review of time allocation theories, a time allocation model for general travel behavior is proposed as a further elaboration of Evans’ (1972) activities analysis. There are relationships among activities that can be expressed using a linear inequality to show the constraints on the arrangement of activities. This model indicates that two or more activities can be simultaneously rearranged to improve time management, which may be a source of variation in VTTS. This time allocation model can explain why large-scale high-speed rail construction in China faces significant market risks and a high likelihood of economic loss. Data from a new ticket sales and booking system for railway passengers indicate that passengers prefer conventional overnight sleeper trains, rather than high-speed trains, for long-distance travel, which supports the analysis of the time allocation model.     

A simple algorithm for the estimation of road traffic space mean speeds from data available to most management centres

The control of the evolution of road traffic streams is highly related to productivity, safety, sustainability and, even, comfort. Although, nowadays, the findings from research efforts and the development of new technologies enable accurate traffic forecasts in almost any conditions, these calculations are usually limited by the data and the equipment available. Most traffic management centres depend on the data provided, at best, by double-loop detectors. These loops supply time means over different aggregation periods, which are indiscriminately used as the bases for subsequent estimations. Since space mean speeds are those needed in most applications (note the fundamental relationship between flow and density in traffic flow theory), most current practice begins with an error. This paper introduces a simple algorithm that the allows estimation of space mean speeds from the data provided by the loops without the need for any additional financial outlay, as long as the traffic in each time interval of aggregation is stationary and its speed distribution is log-normal. Specifically, it is focused on the calculation of the variance of the speeds with regard to the time mean, thus making possible to use the relationship between time mean speeds and space mean speeds defined by Rakha (2005). The results obtained with real data show that the algorithm behaves well if the calculation conditions help fulfil the initial hypotheses. The primary difficulties arise with transient traffic and, in this case, other specific methodologies should be used. Data fusion seems promising in this regard. Nevertheless, it cannot be denied that the improvement provided by the algorithm turns out to be highly beneficial both when used alone in the case of stationarity or as a part of a fusion.     

Energy efficiency and time charter rates: Energy efficiency savings recovered by ship owners in the Panamax market

This paper presents the first analysis on how financial savings arising from energy efficient ships are allocated between owners and those hiring the ships. This as an important undertaking as allocation of financial savings is expected to have an impact on the incentives faced by ship owners to invest in more energy efficient vessels. We focus on the dry bulk Panamax segment as it contributes to around 50 Mt (5%) of total CO₂ emissions from shipping in 2007 and therefore its importance in terms of environmental impact should not be neglected. The time charter market represents a classical example of the principal–agent problem similar to the tenant–landlord problem in the buildings sector. We discovered that on average only 40% of the financial savings delivered by energy efficiency accrue to ship owner for the period 2008–2012. The finding that only part of the savings are recouped by shipowners affecting their incentives towards energy efficiency could consequently have implications on the type of emission reduction policies opted at both, global and regional levels.     

基于供应链管理的库存优化分析

对供应链管理库存控制多级问题进行分析,研究了两种多级库存策略,基于成本优化的多级库存策略,基于时间优化的多级库存策略。两种策略反映了库存管理的一般思想,即库存控制的最优化目标不仅是供应链环节中某一个或几个节点企业的库存最优化,而是整个供应链环节有机、协调地一体化库存的最优化。在此基础上提出了基于时间的多级库存成本优化思路。     

站间通信安全性与可靠性的研究

根据电气化铁路恶劣的电磁环境以及站间通信信道技术的发展，从如何提高站间通信的安全性和可靠性出发，系统地分析了如何利用编码理论，采用切实可行的编码方法，提高信息传输的可靠性，结合编码方法应用时序逻辑控制和Hash算法，有效地提高了站间通信的安全性和可靠性。     

Improved Capacity Spectrum Method Using Structural Inelastic Response

Existing problems of capacity-demand diagram were considered, and the conversion method between the results of the capacitydemand curves method and dynamic time-history analysis is presented. The factors causing the relative error between the different capacity curves, such as the distribution type for lateral load, assumptions of member bar model , surface irregularity of the structures and P-A effects, were analyzed to build the statistical correlation between the maximum base shear and the top displacements of the components under the different pushover analysis. ATC-40 （Procedure-B） method is verified to be more accurate in calculating the roof displacements of buildings. Meanwhile, the improved method is refined in three aspects and proved effective by a real concrete-freme building.