<p>Shiv Nadar University is a comprehensive, multidisciplinary, research-focused, and student-centric University offering a full range of academic programs at the undergraduate, postgraduate and doctoral level. With state-of-the-art infrastructure, the University comprises of academic wings, sophisticated labs, international standard sports facilities, amphitheaters, auditorium, conference rooms and smart classrooms. The University&rsquo;s goal is to become internationally recognized for the quality of its research and creative endeavors and their applicability to improving quality of life, generating new insights and expanding the boundaries of human knowledge creativity. Committed to excellence in teaching, research and service, the University aims to serve the higher education needs of India and the world beyond.</p>

Shiv Nadar University

<p>Road networks are permanent manmade features altering the landscape structure and subsequently influence regional landscape ecology. Taking south-western foothills of Central Himalaya, as a case, this study assessed the spatio-temporal variations in landscape structure and landscape ecological risk (LER) influenced by the road network and topography. The relationship between LER and accessibility factors (distance to different road-types and road kernel density) and topographical factors (elevation and slope) were explored using ordinary least square (OLS) regression and geographically weighted regression (GWR) model. Our results indicate that high-risk LER zones are closer to the road network. This is also in conjunction with increasing built-up areas adjacent to the road network. Regression analysis using GWR model better explained the relationship between LER (dependent variable) and distance from different road-types (independent variables) as compared to OLS with a significant correlation at 1\% confidence interval. The spatial variations in the interrelation between dependent and independent variables were explained using quantified coefficients estimated by the GWR model. The estimation and visualization of spatial associations between landscape structure, LER, and road network provided in our study can act as a baseline for developing a guideline for sustainable infrastructure development and management of ecologically vulnerable landscapes across the tropical world. © 2020 Taylor &amp; Francis Group, LLC.</p>

World University root node

Civil Engineering

(SoE) School of Engineering

Human and Ecological Risk Assessment

Spatio-temporal variations in landscape ecological risk related to road network in the Central Himalaya

Unsafe road crossing behavior by pedestrians is a main contributing factor of pedestrian casualties. Data from 2006 to 2012 in Delhi, India, show that pedestrians have the largest share in total road fatalities. Although facilities such as underpasses and overpasses are often provided to help cross a road, most often, pedestrians do not use them. Pedestrian perceptions play an important role in the use of such facilities. This study examined the relationship between actual crash risk and perceived risk for selecting crossing facilities by pedestrians. The road crossing preferences of pedestrians were analyzed for midblocks, intersections, and locations with a flyover where overpasses and underpasses are provided for road crossing. Responses covering safety and convenience of using specific facilities from one thousand pedestrians were collected through a structured questionnaire on selected locations. A path analysis model, i.e., a special case of structural equation modeling, was developed for analyzing the data. Results show that an inverse relationship exists between actual and perceived crash risks. Crossing behavior in midblocks was found to mediate this relationship. At locations with a flyover, the perspective of convenience was significantly related to the actual crash risk. This study identifies the potentially useful roles that pedestrian perceptions of risk and preferences in road crossing can play in avoiding actual crashes involving pedestrians. Pedestrians’ demographics was also analyzed with perceived risks and preferences for road crossing. From a policy standpoint, the relationships identified between actual and perceived risk and the built environment features of road crossing provide useful information for transportation planners, city planners and engineers. Since perceived risk influences travel behavior, it is important to study influence of perceived crash risk for pedestrians. Proactive interventions are required at the locations with low crash rates as the perceived risk by pedestrians is quite high at these places. This is in addition to the measures required at the locations associated with high actual crash risk faced by pedestrians though these locations are having low perceived crash risk. © 2020 Hong Kong Society for Transportation Studies

Travel Behaviour and Society

Influence of actual and perceived risks in selecting crossing facilities by pedestrians

This study investigates spatio-temporal paradigm of the impact of road networks on urban ecosystem dynamics (UED) by analysing the composition and configuration of land use land cover (LULC) and land surface temperatures (LST) derived from Landsat data for the years 2000 and 2017. The results indicate a positive association between road network and built-up land showing higher concentration of built-up land closer to the road network. This increase in grey infrastructure has led to an increase in the maximum LST by 6 °C to 7.5 °C along primary and tertiary roads, whereas 4 °C to 5 °C along secondary roads. Rapid intensification of road network along with the associated disproportionate changes in LULC and LST are deemed to be the major contributors to UED. Findings from this study will serve as baseline for examining the influence of road network on regional urban growth and assist in sustainable road infrastructure planning. © 2020, © 2020 Informa UK Limited, trading as Taylor & Francis Group.

Geocarto International

Road network drives urban ecosystems - a longitudinal analysis of impact of roads in the central Himalaya

Pedestrian fatalities from 2001 to 2009 in Delhi, India show that pedestrians have the largest share in total road fatalities. Though, facilities like pedestrian underpasses and overpasses are provided to cross the road at several locations, all too often pedestrians do not use them. This study was designed to analyze the pedestrians’ perceptions for underutilization of pedestrian facilities. Five hundred pedestrians were interviewed at seven different locations based on available pedestrian facilities such as zebra crossing, pedestrian underpasses and overpasses. Analysis of usage of these facilities showed that usage of underpasses and zebra crossing is less by female respondents. To know the safety and convenience perception of pedestrians with respect to a specific facility, ordinal logit model was used in this study. Results showed that convenience perception is statistically significant (at 95% CI) for the use of zebra crossings. The conclusions drawn from this study can be used to improve the state of pedestrian facilities in Delhi for prioritization of the facilities based on stated preferences. © 2016 Elsevier Ltd

Transportation Research Part F: Traffic Psychology and Behaviour

Pedestrians perceptions for utilization of pedestrian facilities – Delhi, India

Traffic crash fatalities from 2006 to 09 in Delhi, India show that pedestrians have the largest share in total road fatalities. Perception of risk provides important information to identify potential crash risk. Thus, the main objective of this paper is to explore the pedestrian perception of risk in getting involved in a traffic crash in different locations and the role of built environment features in risk perception of pedestrians. Locations having a high number of pedestrian fatal crashes were identified using GIS map of Delhi. Pedestrian perceptions of risk at forty-five actual crash sites were collected through questionnaire survey. Risk perception of pedestrians of built environment features were analyzed based on pedestrian demographic characteristics. Ordered logit model was used to examine the influence of these variables on risk perception of respondent's neighborhood and of the location where the survey was conducted. Seventy percent respondents perceive the neighborhoods where they reside having higher risk than the actual crash locations. Several factors such as gender, number of lanes, sidewalk width, sidewalk maintenance, traffic speed and traffic volume were significantly associated with perceived risk. Survey sites were further categorized into four groups i.e. foot of flyover, four-way junctions below flyover, midblocks and intersections to find the impact of characteristics of locations on pedestrians' risk perception of different locations. Four-way junctions below flyover were found to have higher perceived risk compared to other locations. © 2016 Elsevier Ltd.

Safety Science

Pedestrians risk perception of traffic crash and built environment features - Delhi, India

An analysis of fatal crashes involving pedestrians in Delhi, India, from 2006 to 2009 that used a geographic information system showed clusters of crashes at certain locations. An evaluation of the characteristics of the built environment around the high crash location clusters was necessary. This paper presents an analysis of the built environment factors that influenced the safety of pedestrians. Locations surveyed included roads around the fatal crash clusters of pedestrians. Factors that influenced the number of fatal crashes of pedestrians were analyzed with negative binomial regression. Types of locations were categorized into locations with a flyover and without a flyover. Results showed that an increase in traffic volume by 1% would increase pedestrian fatal crashes by 1.6% at locations with a flyover and by 0.9% at locations without a flyover. Arterial roads with more traffic volume, more road lanes, and higher speed tended to have more fatal crashes. Locations where medians were fenced or raised in height to prevent pedestrians from crossing were also found to be associated with a greater number of crashes. These findings are useful for improving the safety of pedestrians around specific road infrastructure.