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1.
Julian Arellana María Saltarín Ana Margarita Larrañaga Vilma Alvarez César Augusto Henao 《运输评论》2020,40(2):183-203
ABSTRACTNumerous methodologies measuring walkability have been developed over the last years. This paper reviews the Walkability Index (WI) literature of the last decade (2009–2018) and highlights some limitations in the current approaches. Only a few studies have evaluated walkability in Latin America, mainly in big cities but not in medium and small-sized cities in the region, which present their own urbanisation dynamics, security issues, sidewalk invasion problems, and poor planning. Furthermore, most WIs in the literature use objective mesoscale variables to assess walkability in a given area. This paper contributes to filling these gaps by generating new evidence from a medium-sized city in Latin America to question if characteristics of the built environment encourage walking trips, as found in the literature, are transferable among regions. The study also proposes a novel index comprised of microscale and mesoscale built environment variables to assess walkability using virtual tools and considering users’ perceptions. The WI estimation relies on ranking probability models. The results of the case study suggest that subjective Security and Traffic Safety are the most crucial factors influencing walkability in these kind of cities, which is different from what is found in the literature from cities in developed countries where Sidewalk Condition and Attractiveness are the most important factors. Security appeared to be strongly associated with a subjective dimension, represented by the fear of crime or perceived risk for crime, instead of the actual occurrence of crimes. This result evidences the importance of the physical attributes of the real world and how they are captured, judged, and processed by pedestrians. Then, regional transferability of WIs needs to be done carefully. Finally, results in this paper highlight the importance of microscale built environment characteristics in the WI formulation in these cities. Results are in line with other research in some cities of the region, which found that microscale variables such as pavement quality and presence of obstacles on the sidewalks are relevant components to promote walkability. 相似文献
2.
Romero Fernando Gomez Juan Rangel Thais Jurado-Piña Rafael Vassallo José Manuel 《Transportation》2020,47(4):1665-1687
Transportation - In the field of road transport, Advanced Traveller Information Systems represent a relevant tool to manage road traffic, improve drivers’ utility and make a more efficient... 相似文献
3.
Transportation - Activity sequencing is a crucial component of disaggregate modeling approaches. This paper presents a methodology to analyse and predict activity sequence patterns for persons... 相似文献
4.
Procopiuck Mario Segovia Yenifer Ninosca Silva Procopiuck Ana Paula Vaz 《Transportation》2021,48(4):2055-2080
Transportation - Simultaneously addressing micro-mobility and urban tourism has been a challenge for urban managers formulating cycle-inclusive urban policies in different countries. In this... 相似文献
5.
Transportation - In recent years, climate change emerged as a dominant concern to many parts of the world bringing in huge economic losses disturbing normal business/life. In particular cities are... 相似文献
6.
P. Christopher Zegras Menghan Li Talip Kilic Nancy Lozano-Gracia Ajinkya Ghorpade Marco Tiberti Ana I. Aguilera Fang Zhao 《Transportation》2018,45(2):335-363
The household travel survey (HTS) finds itself in the midst of rapid technological change. Traditional methods are increasingly being sidelined by digital devices and computational power—for tracking movements, automatically detecting modes and activities, facilitating data collection, etc.. Smartphones have recently emerged as the latest technological enhancement. FMS is a smartphone-based prompted-recall HTS platform, consisting of an app for sensor data collection, a backend for data processing and inference, and a user interface for verification of inferences (e.g., modes, activities, times, etc.). FMS, has been deployed in several cities of the global north, including Singapore. This paper assesses the first use of FMS in a city of the global south, Dar es Salaam. FMS in Dar was implemented over a 1-month period, among 581 adults chosen from 300 randomly selected households. Individuals were provided phones with data plans and the FMS app preloaded. Verification of the collected data occurred every 3 days, via a phone interview. The experiment reveals various social and technical challenges. Models of individual likelihood to participate suggest little bias. Several socioeconomic and demographic characteristics apparently do influence, however, the number of days fully verified per individual. Similar apparent biases emerge when predicting the likelihood of a given day being verified. Some risk of non-random, non-response is, thus, evident. 相似文献
7.
Ports are drivers of regional and of countries’ economic development. Most ports are built close to coastlines, where waters are shallower and tend to suffer from deposit sedimentation processes, which reduce depths in operational areas. In presence of shallow waters and sedimentation, ports must decide whether to dredge or not, where both decisions have significant impacts on ports’ annual incomes. Nevertheless, there are seabeds, namely muddy bottoms, in which vessels can navigate with a safety degree. This paper aims at investigating the extent to which the theoretical knowledge of vessel’s control in muddy waters is valid at a certain nautical bottom, as defined by the Permanent International Association of Navigation Congresses (since 2009 the World Association for Waterborne Transport Infrastructure but the acronym stays PIANC) and its impact on port economics. To achieve the proposed objective, an email survey was sent to worldwide pilots that manoeuvre ships in muddy waters. The survey validated the theoretical knowledge, showed that navigation in muddy waters is possible, that it can contribute to reduce ports’ operational costs, and that the subject can be rather controversial. 相似文献
8.
Pablo Coto-Millan Jose Banos-Pino Ana Rodriguez-Alvarez 《Maritime Policy and Management》2013,40(2):169-174
In this study, a stochastic frontier cost function is used to estimate the econmic efficiency of Spanish ports through panel data. The sample covers annual data of 27 Spanish ports from 1985–1989. By comparing a Cobb-Douglas function with a translog, it is found that the latter best represents the technology according to the data. Analysing the efficiency indices obtained, it is found that the relatively larger ports are more economically inefficient. Moreover, the presence of large scale economies has been detected, as well as a lack of technical progress for the period considered. 相似文献
9.
A. López J. Serrat C. Cañero F. Lumbreras T. Graf 《International Journal of Automotive Technology》2010,11(3):395-407
Detection of lane markings based on a camera sensor can be a low-cost solution to lane departure and curve-over-speed warnings.
A number of methods and implementations have been reported in the literature. However, reliable detection is still an issue
because of cast shadows, worn and occluded markings, variable ambient lighting conditions, for example. We focus on increasing
detection reliability in two ways. First, we employed an image feature other than the commonly used edges: ridges, which we
claim addresses this problem better. Second, we adapted RANSAC, a generic robust estimation method, to fit a parametric model
of a pair of lane lines to the image features, based on both ridgeness and ridge orientation. In addition, the model was fitted
for the left and right lane lines simultaneously to enforce a consistent result. Four measures of interest for driver assistance
applications were directly computed from the fitted parametric model at each frame: lane width, lane curvature, and vehicle
yaw angle and lateral offset with regard the lane medial axis. We qualitatively assessed our method in video sequences captured
on several road types and under very different lighting conditions. We also quantitatively assessed it on synthetic but realistic
video sequences for which road geometry and vehicle trajectory ground truth are known. 相似文献
10.