Kees Maat

Bio: Kees Maat is an academic researcher from Delft University of Technology. The author has contributed to research in topics: Travel behavior & Mode choice. The author has an hindex of 27, co-authored 70 publications receiving 4352 citations.

Deriving and validating trip purposes and travel modes for multi-day GPS-based travel surveys: A large-scale application in the Netherlands

Abstract: In the past few decades, travel patterns have become more complex and policy makers demand more detailed information. As a result, conventional data collection methods seem no longer adequate to satisfy all data needs. Travel researchers around the world are currently experimenting with different Global Positioning System (GPS)-based data collection methods. An overview of the literature shows the potential of these methods, especially when algorithms that include spatial data are used to derive trip characteristics from the GPS logs. This article presents an innovative method that combines GPS logs, Geographic Information System (GIS) technology and an interactive web-based validation application. In particular, this approach concentrates on the issue of deriving and validating trip purposes and travel modes, as well as allowing for reliable multi-day data collection. In 2007, this method was used in practice in a large-scale study conducted in the Netherlands. In total, 1104 respondents successfully participated in the one-week survey. The project demonstrated that GPS-based methods now provide reliable multi-day data. In comparison with data from the Dutch Travel Survey, travel mode and trip purpose shares were almost equal while more trips per tour were recorded, which indicates the ability of collecting trips that are missed by paper diary methods.

The role of attitudes toward characteristics of bicycle commuting on the choice to cycle to work over various distances

Abstract: This paper analyses the influence of commuters' attitudes toward the benefits of travel by bicycle (e.g. convenience, low cost, health benefits) on the mode choice decision for commutes to work. We assume that when the commute journey intensifies, either in terms of distance or frequency, attitudes toward cycling become more positive. Factor analysis reveals three underlying attitudinal factors toward cycling to work: awareness, direct trip-based benefits and safety. The decision to cycle is influenced by the factor "direct trip-based benefit" at all distances, whereas the "awareness" is influential only over long distances. The decision to cycle every day is again affected by the "direct benefit" factor. The factors "safety" and "awareness" are important over shorter distances. Having a cycling habit increases the likelihood of cycling and a higher frequency of cycling. The perceived opinion of others only affects the mode choice over short distances suggesting indicates mode choice on longer commutes is based on one's own attitudes. These findings indicate that attitudes and other psychological factors have a relatively strong impact on the choice to commute by bicycle.

A method to evaluate equitable accessibility: combining ethical theories and accessibility-based approaches

Abstract: In this paper, we present the case that traditional transport appraisal methods do not sufficiently capture the social dimensions of mobility and accessibility. However, understanding this is highly relevant for policymakers to understand the impacts of their transport decisions. These dimensions include the distribution of mobility and accessibility levels over particular areas or for specific population groups, as well as how this may affect various social outcomes, including their levels of participation, social inclusion and community cohesion. In response, we propose a method to assess the socially relevant accessibility impacts (SRAIs) of policies in some of these key dimensions. The method combines the use of underlying ethics principles, more specifically the theories of egalitarianism and sufficientarianism, in combination with accessibility-based analysis and the Lorenz curve and Gini index. We then demonstrate the method in a case study example. Our suggestion is that policymakers can use these ethical perspectives to determine the equity of their policies decisions and to set minimum standards for local transport delivery. This will help them to become more confident in the development and adoption of new decision frameworks that promote accessibility over mobility and which also disaggregate the costs and benefits of transport policies over particular areas or for specific under-served population groups.

Nature and Health

Abstract: Urbanization, resource exploitation, and lifestyle changes have diminished possibilities for human contact with nature in many societies. Concern about the loss has helped motivate research on the health benefits of contact with nature. Reviewing that research here, we focus on nature as represented by aspects of the physical environment relevant to planning, design, and policy measures that serve broad segments of urbanized societies. We discuss difficulties in defining “nature” and reasons for the current expansion of the research field, and we assess available reviews. We then consider research on pathways between nature and health involving air quality, physical activity, social cohesion, and stress reduction. Finally, we discuss methodological issues and priorities for future research. The extant research does describe an array of benefits of contact with nature, and evidence regarding some benefits is strong; however, some findings indicate caution is needed in applying beliefs about those benefits,...

Batteries and fuel cells for emerging electric vehicle markets

Abstract: Today’s electric vehicles are almost exclusively powered by lithium-ion batteries, but there is a long way to go before electric vehicles become dominant in the global automotive market. In addition to policy support, widespread deployment of electric vehicles requires high-performance and low-cost energy storage technologies, including not only batteries but also alternative electrochemical devices. Here, we provide a comprehensive evaluation of various batteries and hydrogen fuel cells that have the greatest potential to succeed in commercial applications. Three sectors that are not well served by current lithium-ion-powered electric vehicles, namely the long-range, low-cost and high-utilization transportation markets, are discussed. The technological properties that must be improved to fully enable these electric vehicle markets include specific energy, cost, safety and power grid compatibility. Six energy storage and conversion technologies that possess varying combinations of these improved characteristics are compared and separately evaluated for each market. The remainder of the Review briefly discusses the technological status of these clean energy technologies, emphasizing barriers that must be overcome. Recent years have seen significant growth of electric vehicles and extensive development of energy storage technologies. This Review evaluates the potential of a series of promising batteries and hydrogen fuel cells in their deployment in automotive electrification.

Rapidly falling costs of battery packs for electric vehicles

Abstract: A systematic analysis reveals a steep decline in the costs of battery packs for electric vehicles, with market-leading manufacturers setting the pace.

Electrically Rechargeable Zinc–Air Batteries: Progress, Challenges, and Perspectives

Abstract: Zinc-air batteries have attracted much attention and received revived research efforts recently due to their high energy density, which makes them a promising candidate for emerging mobile and electronic applications. Besides their high energy density, they also demonstrate other desirable characteristics, such as abundant raw materials, environmental friendliness, safety, and low cost. Here, the reaction mechanism of electrically rechargeable zinc-air batteries is discussed, different battery configurations are compared, and an in depth discussion is offered of the major issues that affect individual cellular components, along with respective strategies to alleviate these issues to enhance battery performance. Additionally, a section dedicated to battery-testing techniques and corresponding recommendations for best practices are included. Finally, a general perspective on the current limitations, recent application-targeted developments, and recommended future research directions to prolong the lifespan of electrically rechargeable zinc-air batteries is provided.