Influence of the weather on mode choice in corridors with time-varying congestion: a mixed data study

Studies that link human behaviour to the influence of weather have historically been conducted in such fields as tourism, marketing and leisure. In most studies that jointly examine weather and the mode of transport, only open-air transportation has been considered (for example, bicycle, motorcycle or walking). This focus, together with the habitual use of data collected with automatic devices and a lack of studies that analyse this issue using stated preference data, are the main reasons motivating this paper. This paper aims to analyse the influence of weather and the density of traffic on the choice of transport mode. A case study is conducted in an access/egress corridor located in the city of Barcelona (Spain). Two data sources were used: revealed preference and stated preference data. Modelling techniques using mixed data enabled the stronger features from both data sources to be captured. Finally, we discuss how the selection of different alternative specific constants in models estimated using mixed data could generate unrealistic forecasting results if environmental changes are expected in the actual market.     

Bicycle commuting in an automobile-dominated city: how individuals become and remain bike commuters in Charlotte,North Carolina

Transportation - In Charlotte, North Carolina less than one half of 1% of commuters ride a bicycle to work despite several decades of public investment in bicycle infrastructure and planning. Like...     

遮阳棚对隧道进出口明暗适应的影响规律研究北大核心CSCD

为研究隧道进出口路段驾驶员明暗适应的特性及遮阳棚对明暗适应过程的影响规律,文章依托紫荆隧道(无遮阳棚)及巴朗山隧道(有遮阳棚)进行驾驶试验,以驾驶员瞳孔直径及其变化速率为研究参数,分析遮阳棚对隧道进出口路段明暗适应的缓冲效果。研究结果表明:暗适应过程90%以上发生在洞内段,明适应过程54.61%以上发生在洞内段;在隧道进口段暗适应过程中,通过遮阳棚时间为2 s时,最大瞳孔直径变化速率下降4.84%,通过遮阳棚时间为5 s时,最大瞳孔直径变化速率下降33.58%;在隧道出口段明适应过程中,通过遮阳棚时间为2 s时,最大瞳孔直径变化速率下降38.75%,通过遮阳棚的时间为5 s时,最大瞳孔直径变化速率下降49.97%。     

基于SVM的隧道衬砌空洞填充物雷达图像识别研究北大核心CSCD

衬砌背后空洞及其填充物对隧道结构安全具有重要影响,开展空洞探测识别对于结构安全评估和病害处置具有重要意义。首先采用室内试验和FDTD正演模拟相结合的方法,获得了空洞内填充空气、水、干砂、湿砂条件下的雷达图谱数据,并对不同填充物波形规律进行对比分析;然后,基于支持向量机算法对波形特征进行提取和分类识别,建立了一种空洞填充物的人工智能辨识方法。研究结果表明,采用傅里叶变换前的平均值、方差、平均绝对离差和傅里叶变换后的最大幅度值max(fft(X))四个统计量作为支持向量机的识别特征,可以有效区分出衬砌背后填充物的六种类型;当采取单一倾向数据时,识别准确率较好,六种物质二分类问题准确率均可以达到90%以上。     

Hydroelastic analysis of a rectangular plate subjected to slamming loads

A hydroelastic analysis of a rectangular plate subjected to slamming loads is presented. An analytical model based on Wagner theory is used for calculations of transient slamming load on the ship plate. A thin isotropic plate theory is considered for determining the vibration of a rectangular plate excited by an external slamming force. The forced vibration of the plate is calculated by the modal expansion method. Analytical results of the transient response of a rectangular plate induced by slamming loads are compared with numerical calculations from finite element method. The theoretical slamming pressure based on Wagner model is applied on the finite element model of a plate. Good agreement is obtained between the analytical and numerical results for the structural deflection of a rectangular plate due to slamming pressure. The effects of plate dimension and wave profile on the structural vibration are discussed as well. The results show that a low impact velocity and a small wetted radial length of wave yield negligible effects of hydroelasticity.     

Multisite,Interdisciplinary Applications of Science to Marine Policy: The Conservation International Marine Management Area Science Program

This special issue provides insight into global conservation science by analyzing a 5-year, $12.5 million global marine conservation science and policy program that included over 50 studies in four priority regions involving over 100 scientists and numerous partners. In doing so, it provides reflections on critical challenges for any conservation science program that is intended to inform policymaking, including how to (1) ensure that science process and products influence conservation actions, (2) build global learning from a network of site-based projects, (3) strengthen in-region capacity, and (4) manage relationships across scales among scientists, conservationists, headquarters, and field-based staff. Information is presented on the development and progress of the program as a whole in addition to specific articles covering each of four focal geographic areas: Belize, Brazil, the Eastern Tropical Pacific Seascape, and Fiji.     

A New Coastal Policy for South Africa

Treaties on Trial: The Continuing Controversy Over Northwest Indian Fishing Rights by Fay G. Cohen (Seattle: University of Washington Press, 1986), 229 pages.     

Developing MPA Effectiveness Indicators: Comparison Within and Across Stakeholder Groups and Communities

Shared expectations about marine protected areas (MPAs) might be expected to enhance their effectiveness. This study determined whether members of local communities had common or divergent views about the objectives and indicators of MPA effectiveness. In the central Philippines we used unconstrained and constrained methods to interview people in five stakeholder groups (elders, fishers, leaders, women, and youth) associated with each of 10 community-based no-take MPAs that had been protected between 0 and 21 years. Respondents identified multiple MPA objectives, the most frequently mentioned of which was restoring and sustaining fish populations. The results suggest that MPA age accounts for the greatest level of variation across communities. When unconstrained, progress in enforcement was identified as a key indicator among respondents from younger MPAs while respondents from older MPAs identified increased fish abundance and catch. Although consensus can be reached more easily under constrained conditions, the results derived from unconstrained methods are more revealing of the needs and aspirations of communities. These are likely to contribute more to the search for appropriate management interventions, particularly given that MPAs evolve over time. Hence, the development of MPA effectiveness indicators must be an iterative community-informed process to ensure timely and relevant management interventions.     

Estuary Management and Recreational Fishing Benefits

Recognition of the benefits to society supported by estuary ecosystem functions and services, and threats to these benefits posed by human activities, has led to various public programs to restore and protect estuaries at the federal, state, and local levels. As available budgets shrink, program administrators and public elected officials struggle to allocate limited restoration and protection funds to the highest priority areas. Economic benefit and cost information can provide useful inputs into this decision-making process by quantifying estuary restoration and protection benefits and costs in commensurate terms. In this paper, a combined actual and intended travel behavior model is described that can be applied to estimate the recreational fishing benefits of estuary restoration and protection. The model was estimated for recreational fishing in the Lower Atchafalaya River Basin estuary along the Gulf of Mexico, Louisiana, USA coast. Changes in freshwater flows into this estuary may affect redfish and speckled trout game fish populations. The model indicates that changes in catch rates of these two species would have a relatively minor affect on annual fishing trips per angler. However, because total effects may be large when effects per angler are aggregated across total anglers, resource management agencies should consider these changes in recreation benefits when evaluating projects that influence the ecology of coastal estuaries, fish populations, and catch rates. Moreover, in other coastal areas or situations, the responsiveness of angling trips to changes in catch rates may vary because of differences in user populations, environmental conditions, fish populations, and fishing experiences.