Value of travel time reliability: A review of current evidence

Travel time reliability is a fundamental factor in travel behavior. It represents the temporal uncertainty experienced by travelers in their movement between any two nodes in a network. The importance of the time reliability depends on the penalties incurred by the travelers. In road networks, travelers consider the existence of a trip travel time uncertainty in different choice situations (departure time, route, mode, and others). In this paper, a systematic review of the current state of research in travel time reliability, and more explicitly in the value of travel time reliability is presented. Moreover, a meta-analysis is performed in order to determine the reasons behind the discrepancy among the reliability estimates.     

Sea Cucumber Moratorium and Livelihood Diversity in Papua New Guinea

Livelihood diversity factors such as flexibility within fisheries, geographical mobility, reallocation of fishing effort into the broader economy, and the non-material benefits that fisheries provide are important areas of research in marine policy. We use two small-scale fisheries related socio-economic surveys of communities in the Tigak Islands of Papua New Guinea. The first conducted 5 years before a ban on the harvesting of sea cucumbers was imposed and the second from the present day, 5 years after the initiation of the ban—with the objectives of exploring changes in household fishing strategies (types and numbers of species targeted) and to identify any important socioeconomic factors that help explain those changes. Fishing's contribution to total household income has increased significantly (p = 0.019) up from 61% in 2004 to 73% in 2014 with the percentage of female residents living in a household now positively and significantly (p = 0.018) associated with fishing income. The average number of species categories targeted per household increased insignificantly while households with more women are significantly (p = 0.018) less likely to target more species than households with more men. Moreover, customary management practices contribute to this difference. Together, these results show that households are not worse off financially 5 years after the ban on sea cucumber harvesting and that gendered seascape use has implications for the role of livelihood diversity as a marine policy tool.     

“Local background” levels of carbon monoxide in an urban area

The objective of this study was to obtain a better understanding of carbon monoxide (CO) concentrations immediately upwind of urban roadways, the “local background” values, and how these concentrations depend upon the surrounding traffic and the general meteorology. Measurements were made at seven sites in Seattle, WA during the winter of 1993. Local background CO concentrations were characterized by an absence of short term fluctuations, a steady buildup during the 3 p.m. to 11 p.m. period, and a lack of spatial gradients in the 8-h average values. Distinctly different log-normal distributions of the 8-h averages were observed for “trafficked” sites versus “urban park” sites, with mean values of 1.6 and 1.0 ppm respectively. A simple regression model was developed to predict the local background CO that includes distance from roadway, average daily traffic of nearby roadways, and the frequency of occurrence of low wind speeds (R² = 0.74; F = 170).     

The influence of habit formation on modal choice —a Heuristic model

Most modal split models have been based on the assumption of rational behaviour in an individual's choice evaluation of the generalised costs of modal alternatives. This paper integrates conceptual and empirical information from a wide range of sources and points towards an alternative way of looking at modal choice. The main conclusion is that the car is usually perceived as the superior mode for vehicular travel and that the potential user is committed to its use largely through the act of purchasing it. The conceptual structure of a sequential modal split model is outlined as one that is based on a four-stage decision-making framework which considers the role of learning and habit-formation. In the conclusion, the implications of this approach are considered in terms of the conventional modal split and trip generation submodels, and certain policy measures are assessed.     

The role of information in ocean-shipping management

In this article the nature of information in the ocean shipping industry is analysed and an information system for processing industry data is outlined. The system collects and verifies data from many sources and supplies input for the decision-maker, in a comprehensible format, based on facts and not on estimates. Typical applications of the system are discussed and their impact in several cases is presented.     

An assignment principle for urban networks based on travel budgets

A new assignment principle for traveler behavior in an urban network is described which is based on empirical findings in the theory of travel budgets. It characterizes the distribution of travelers, demand, and modal split. It treats all travel decisions (whether to travel, where to go, how to get there) and the important costs (time and money) in a single, unified way. A numerical technique is proposed and it is applied to several examples to illustrate qualitative features.     

The simulation of a fork-lift truck and crane transfer operation

The authors of this paper make use of computer simulation techniques as a means of investigating the problems associated with minimizing a ship's turn-round time.     

Reported household gasoline purchasing experience: June 1979

A sample of 1000 households completed a questionnaire regarding difficulties encountered purchasing gasoline during the week 4–10 June 1979 and whether difficulties encountered purchasing gasoline affected household automobile tripmaking. Results of this survey were analyzed and it was found that the frequency of reporting purchasing difficulties varied directly with household income and inversely with the age of the household. The frequency of reporting that purchasing difficulties affected automobile trip-making varied directly with household income and inversely with the number of adults in the household. Further, although individual household response was highly sensitive to socioeconomic characteristics, the overall response to the survey would not have differed significantly had the socioeconomic mix of households been different.