The effect of neighbourhood characteristics,accessibility, home–work location,and demographics on commuting distances

The goal of this paper is to better understand home-to-work travel distances throughout the Montréal Metropolitan region. A simultaneous equation modelling analysis is carried out to jointly explain commuter trip length and home–work location as a function of neighbourhood typologies, commuter socio-demographics and measures of job and worker accessibility. First, a factor and cluster analysis of urban form is performed over the entire region on a fine-scale grid pattern. The outcome of this analysis is the classification of typologies at both home and job locations. Different measures of accessibility and commuter socio-demographics are then incorporated into the analysis. Varied data sources including a detailed Montréal Origin–Destination Survey on over 30,000 home-to-work automobile trips are analyzed. Among other results, commuters that live and work in a different sub-region almost double the average trip distance and although socio-economic factors have a statistically significant correlation with commuter distance, these factors have a marginal effect. Interestingly, our results highlight the importance of urban form and job accessibility. Deciding on whether to live and work in the same sub-region was modelled as an endogenous binary random utility model; unobserved heterogeneities seem to be simultaneously influencing both the home–work location choice and trip-to-work distances. Our results underscore the importance of home–work location with respect to urban form and job accessibility. Hence, policies that support more dense and mixed land-use in suburban areas would not be enough to reduce commuter distances. These actions should be accompanied by other policy initiatives to discourage long car trips.     

Experimental Investigation of a Hydraulic Turbine for Hydrokinetic Power Generation in Irrigation/Rainfall Channels

The development of microchannels with open flow for use in irrigation and rainy areas is challenged by electricity generation via hydrokinetic devices in shallo...     

Review of magnetorheological （MR） fluids and its applications in vibration control

1 Introduction1 Magnetorheological is a branch of Rheology that deals with the flow and deformation of the materials under an applied magnetic field. The discovery of MR fluids is credited to Jacob Rabinow[2,3] in 1949. Magnetorheological (MR) fluids are …     

Performance evaluation of energy meters under nonlinear loads

Due to rapid advancements in power electronics, the utilization of electronically switched loads and nonlinear loads is increasing gradually in the electrical power system. These loads create problems of measuring instruments, when connected to the power distribution systems. In this paper, an experimental investigation has been carried out to analyze the performance of single-phase watt-hour (induction and electronic types) energy meters that are being used in Pakistan. The accuracy of the energy meters has been tested under different household nonlinear loads, at various power factors and also at different supply voltage levels. Power factor and total harmonic distortion (THD) of different household loads are also recorded in the experimental work. A hardware based experimental setup has been designed to perform the experimental work. The experimental results have been compared to Water and Power Development Authority (WAPDA) standards for energy meters.     

Adjusting the service? Understanding the factors affecting bus ridership over time at the route level in Montréal,Canada

Transportation - Like many cities across North America, Montréal has experienced shrinking bus ridership over recent years. Most literature has focused on the broader causes for ridership...     

Rescuing the captive [mode] user: an alternative approach to transport market segmentation

The prevailing approach to transport market segmentation which identifies two distinct groups, “captive” and “choice” users, has widely been used by professionals and scholars despite the ambiguity associated with these terms. Furthermore, conflicting interpretations from the point of view of decision makers and individuals may result in negative policy implications where the needs of captive users are neglected in favour of attracting new users. This study attempts to address these concerns by proposing an alternative segmentation framework that could be applied to any mode of transport, in any regional context, by users and decision makers alike to better guide the development of transport policies. Using the results of a large-scale transportation survey, a series of clustering techniques are employed to derive this alternative approach for segmenting walkers, cyclists, transit and automobile users. The main factors considered in the final clustering analysis are the level of trip satisfaction and practicality. The analysis yielded four market segments: captivity, utilitarianism, dedication and convenience. Using this theoretical framework to understand the distribution of travellers among market segments is essential in identifying distinct and appropriate policy interventions to improve trip conditions. It is hoped that the segmentation approach and policy framework proposed here will encourage a better balance between pragmatic and idealistic goals in transportation policy.     

Behavioral factors of motorcyclists in right-turn movements at unsignalized intersections: An insight from Yogyakarta,Indonesia

Conflicting actions of motorcyclists making right-turn movements (RTM) pose a considerable risk of accidents, which is of great concern when attempting to augment the level of safety at unsignalized intersections. This study was conducted to identify the habits of motorcyclists in RTMs, including normal RTM, weaving/merging RTM, and opposite indirect RTM when crossing unsignalized intersections. The behavioral factors were affected by gender, passenger status, motorcycle type, STOP factor, speed, travel time, and lane width of major and minor roads, which were tested using multinomial and nested logit models on 2358 motorcyclists. The results indicated that all of the observed variables significantly influenced motorcyclists' behaviors at unsignalized intersections, excepting the variable of travel time. The factors of speed and lane width on minor roads significantly correlated to motorcyclist behaviors during weaving and merging RTM only. The logit model reveals that female motorcyclists tend to make normal RTMs. The study also proposes ideal and practical recommendations, such as stop and speed regulations, channelization, number of lanes and lane widths, and maneuver markers, in order to address dangerous behaviors, in particular weaving and merging and opposite indirect-type RTMs.     

A discrete optimization approach for locating Automatic Vehicle Identification readers for the provision of roadway travel times

This paper develops an algorithm for optimally locating Automatic Vehicle Identification tag readers by maximizing the benefit that would accrue from measuring travel times on a transportation network. The problem is formulated as a quadratic 0–1 optimization problem where the objective function parameters represent benefit factors that capture the relevance of measuring travel times as reflected by the demand and travel time variability along specified trips. An optimization approach based on the Reformulation–Linearization Technique coupled with semidefinite programming concepts is designed to solve the formulated reader location problem. To illustrate the proposed methodology, we consider a transportation network that is comprised of freeway segments that might include merge, diverge, weaving, and bottleneck sections. In order to derive benefit factors for the various origin–destination pairs on this network, we employ a simulation package (INTEGRATION) in combination with a composite function, which estimates the travel time variability along a trip that is comprised of links that include any of the four identified sections. The simulation results are actually recorded as generic look-up tables that can be used for any such section for the purpose of computing the associated benefit factor coefficients. Computational results are presented using data pertaining to a freeway section in San Antonio, Texas, as well as synthetic test cases, to demonstrate the effectiveness of the proposed approach, and to study the sensitivity of the quality of the solution to variations in the number of available readers.     

Road disturbance estimation for the optimal preview control of an active suspension systems based on tracked vehicle model

This research investigates stochastic estimation of a look-ahead sensor scheme using the optimal preview control for an active suspension system of a full tracked vehicle (FTV). In this scheme, wheel disturbance input to the front wheels are estimated using the dynamic equations of the system. The estimated road disturbance input at the front wheels are utilized as preview information for the control of subsequently following wheels of FTV. The design of optimal preview control is used as a classical linear quadratic Gaussian problem by combining dynamics of the original system and estimation of previewed road inputs. The effectiveness of the preview controller is evaluated by comparing the estimated information with the measured information for different road profiles, where Kalman filter is used for the state-variables estimation of the FTV. This research also considers the reduced order estimation using commonly available sensors in order to decrease the number of sensors and measurements. The simulation results’ using an active suspension system with different preview information shows that the proposed system can be beneficial for the improvement of ride comfort of tracked vehicles without using any specialized sensors for preview information calculation.     

Development of 19-plex Y STR system and polymorphism studies in Pakistani population

For the development of 19-plex Y STR system and polymorphism studies in locl ethnic populations sixteen markers of non-recombining regions (NRY) of Y chromosome, which show high power of discrimination among individuals, were selected in this study. Blood samples (600) were e.ollected from the males of three most common castes of Pakistani population (Arnin, Awan and Rajput) with different parent lineages. Three markers (DYS385a/b, DYS389Ⅰ/Ⅱ and YCAⅡa/b) among 16 Y STRs are double-targeted regions of the Y chromosome and thus provide two polymorphie peaks for each respective primer set. These 16 Y-STRs were developed into Megaplex system for simultaneous amplification of all markers within the population. The overall power of discrimination observed in focused populations was 60.5%, 66.5% and 55% in Rajput, Awan and Arain casts respectively. This discrimination power will be helpful in haman identification for forensic casework studies including sexual assaults and paternity testing.