Defining and Generating Axial Lines from Street Center Lines for better Understanding of Urban Morphologies

Axial lines are defined as the longest visibility lines for representing individual linear spaces in urban environments. The least number of axial lines that cover the free space of an urban environment or the space between buildings constitute what is often called an axial map. This is a fundamental tool in space syntax, a theory developed by Bill Hillier and his colleagues for characterizing the underlying urban morphologies. For a long time, generating axial lines with help of some graphic software has been a tedious manual process that is criticized for being time consuming, subjective, or even arbitrary. In this paper, we redefine axial lines as the least number of individual straight line segments mutually intersected along natural streets that are generated from street center lines using the Gestalt principle of good continuity. Based on this new definition, we develop an automatic solution to generating the newly defined axial lines from street center lines. We apply this solution to six typical street networks (three from North America and three from Europe), and generate a new set of axial lines for analyzing the urban morphologies. Through a comparison study between the new axial lines and the conventional or old axial lines, and between the new axial lines and natural streets, we demonstrate with empirical evidence that the newly defined axial lines are a better alternative in capturing the underlying urban structure. Keywords: Space syntax, street networks, topological analysis, traffic, head/tail division ruleComment: 10 pages, 7 figures, and 2 tables, one figure added + minor revisio

Driver’s Visual Engagement in Urban Streetscape

Representation of visual engagement in urban street through the streetscape is an important in urban design research as a city framework. Urban street are composed of various classifications and attract more attention from townspeople. Visual engagement is an important component for understanding a city. Human's perception of the nature environment and build environment gives a difference feeling to the visual. The city formed by many urban street that forms it. However, the establishment of this street still does not pay attention to the interests about visual on the street system as a city frameworks, but only pay attention to the function of the street. Urban street have regulations related to speed limits that are affect the visual of the driver. The importance of visual engagement driver’s when through the street to understanding of the city. The methodology in this study uses a post-positivist paradigm with quantitative strategies. Data collection tactics using Likert scale questionnaires was given to drivers or people who through the street by car with intensity once a week and data analysis uses SPSS application with descriptive statistics to identify factors that the most affect. The results of this study are to identify the factors of the urban streetscape that the most affect to the drivers when through the street. The visual elements factor that include the mass of the building, building entrance, textures, colours, and materials was establish the enclosure space on the street corridor. from these results identified a new factors that affect to visual engagement drivers

Shortest path or anchor-based route choice: a large-scale empirical analysis of minicab routing in London

Understanding and modelling route choice behaviour is central to predicting the formation and propagation of urban road congestion. Yet within conventional literature disagreements persist around the nature of route choice behaviour, and how it should be modelled. In this paper, both the shortest path and anchor-based perspectives on route choice behaviour are explored through an empirical analysis of nearly 700,000 minicab routes across London, United Kingdom. In the first set of analyses, the degree of similarity between observed routes and possible shortest paths is established. Shortest paths demonstrate poor performance in predicting both observed route choice and characteristics. The second stage of analysis explores the influence of specific urban features, named anchors, in route choice. These analyses show that certain features attract more route choices than would be expected were individuals choosing route based on cost minimisation alone. Instead, the results indicate that major urban features form the basis of route choice planning – being selected disproportionately more often, and causing asymmetry in route choice volumes by direction of travel. At a finer scale, decisions made at minor road features are furthermore demonstrated to influence routing patterns. The results indicate a need to revisit the basis of how routes are modelled, shifting from the shortest path perspective to a mechanism structured around urban features. In concluding, the main trends are synthesised within an initial framework for route choice modelling, and presents potential extensions of this research

Straight to the Point: How people encode linear discontinuations

Spatial discontinuations, as those found in cities and buildings, are everyday events. But, how do we encode and classify such misalignments? This is the topic of this paper. Twenty participants were asked to classify a total of 51 icons showing an upward-moving line being misaligned to the right, left and straight down. The results show that subjects were very sensitive to slight discontinuations occurring to vertical lines and that there was not exact symmetry between the left and right axis, meaning that the pieces slightly misaligned to the left were encoded differently than those misaligned to the right.Fil: Mora, Rodrigo I.. Universidad Diego Portales; ChileFil: Lobos, Alejandro. Universidad Diego Portales; ChileFil: Ibañez, Agustin Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto de Neurología Cognitiva; Argentina. Universidad Diego Portales; Chil

Differences of Street Connectivity Between Old And New Zones In Malaysian Small Town

From the period before Malaysia’s independence until now, there are two significant characteristics of the town formed in small town. Pedestrian behavior in the streets is affected by the connectivity existed from the pattern of the street network of a town. Thus, the existing of characteristics of new and old zone require pedestrian to travel differently in those environments. By considering a small town consists of the old and new zone and population between 30,000 to 100,000, street network of Bandar Teluk Intan, Perak was selected. Three sets of data were produced from the land use map and Google Map image, then analyzed it using UCL Depthmap 10. Firstly, solid and void data was used in Visibility graph analysis to measure street connectivity from pedestrian visualization. Second data which convex space data used in Convex space graph analysis to measure street connectivity of spaces in street network that offer pedestrian interaction. Axial-line data is the third data was used in Axial-line graph analysis to measure street connectivity from pedestrian movement in street network. Finding shows that in old zone, junctions act as a connector to other streets when pedestrian visualize during travel, space in square and market chosen as meeting place, and main road as a guide when pedestrian move. In new zone, main road is a connecting feature for pedestrian because it's easy to find, connect with most streets, and the possible space to meet people during travel

Computing the Fewest-turn Map Directions based on the Connectivity of Natural Roads

In this paper, we introduced a novel approach to computing the fewest-turn map directions or routes based on the concept of natural roads. Natural roads are joined road segments that perceptually constitute good continuity. This approach relies on the connectivity of natural roads rather than that of road segments for computing routes or map directions. Because of this, the derived routes posses the fewest turns. However, what we intend to achieve are the routes that not only possess the fewest turns, but are also as short as possible. This kind of map direction is more effective and favorable by people, because they bear less cognitive burden. Furthermore, the computation of the routes is more efficient, since it is based on the graph encoding the connectivity of roads, which is significantly smaller than the graph of road segments. We made experiments applied to eight urban street networks from North America and Europe in order to illustrate the above stated advantages. The experimental results indicate that the fewest-turn routes posses fewer turns and shorter distances than the simplest paths and the routes provided by Google Maps. For example, the fewest-turn-and-shortest routes are on average 15% shorter than the routes suggested by Google Maps, while the number of turns is just half as much. This approach is a key technology behind FromToMap.org - a web mapping service using openstreetmap data.Comment: 12 pages, 5 figures, and 4 tables, language editing, some significant revisions, missing references adde

Street-based Topological Representations and Analyses for Predicting Traffic Flow in GIS

It is well received in the space syntax community that traffic flow is significantly correlated to a morphological property of streets, which are represented by axial lines, forming a so called axial map. The correlation co-efficient (R square value) approaches 0.8 and even a higher value according to the space syntax literature. In this paper, we study the same issue using the Hong Kong street network and the Hong Kong Annual Average Daily Traffic (AADT) datasets, and find surprisingly that street-based topological representations (or street-street topologies) tend to be better representations than the axial map. In other words, vehicle flow is correlated to a morphological property of streets better than that of axial lines. Based on the finding, we suggest the street-based topological representations as an alternative GIS representation, and the topological analyses as a new analytical means for geographic knowledge discovery.Comment: 14 pages, 9 figures, 6 tables, submitted to International Journal of Geographic Information Scienc

This is the tricky part: When directions become difficult

Automated route guidance systems, both web-based systems and en-route systems, have become commonplace in recent years. These systems often replace humangenerated directions, which are often incomplete, vague, or in error. However, humangenerated directions have the ability to differentiate between easy and complex steps through language in a way that is more difficult in automated systems. This article examines a set of human-generated verbal directions to better understand why some parts of directions are perceived as being more difficult than the remaining steps. Insights from this analysis will lead to recommendations to improve the next generation of automated route guidance systems

This is the tricky part: When directions become difficult

Automated route guidance systems, both web-based systems and en-route systems, have become commonplace in recent years. These systems often replace human-generated directions, which are often incomplete, vague, or in error. However, human-generated directions have the ability to differentiate between easy and complex steps through language in a way that is more difficult in automated systems. This article examines a set of human-generated verbal directions to better understand why some parts of directions are perceived as being more difficult than the remaining steps. Insights from this analysis will lead to recommendations to improve the next generation of automated route guidance systems