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31.
Using the nationally representative dataset of the 2007 Pakistan Time-Use Survey, this paper examines gender differences in daily trip rate, mode choice, travel duration, and purpose of travel, which are previously unreported because of limited data availability. Wide gender mobility gaps are observed in the country, where women are less likely to travel, are half as mobile as men and may rely heavily on walking. The particular social and cultural context of the country, that renders women as private, secluded and family honor, seems influential in shaping their mobility and choice of activities. Demographic factors such as age, household income, and marital status significantly decrease female mobility levels. Hence, these findings call for a gender-based culturally responsive transportation policy in the country.  相似文献   
32.
本文研究了某护卫舰的再设计和再分析,用有限元法计算了舰船船体中剖面构件的应力,用修正缩减基法对护卫舰进行了结构再分析。  相似文献   
33.
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 …  相似文献   
34.
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.  相似文献   
35.
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.  相似文献   
36.

Most airlines across Asia are struggling to cope with an unprecedented economic crisis which they have very little control over, and the survival of some remains in doubt. The continuing uncertainty generated by the crisis has accelerated the process of change in the aviation industry and has highlighted the need for adaptability, and its effects have been deeper and longer lasting than previously anticipated. After a year-long slump in the Asian travel market, airlines are now considering a range of options and rehabilitation programmes including a series of cost-cutting measures. There appears to be a trend towards the extension and consolidation of strategic alliances, structural and operational reorganization, and the application of new technologies. The success of these measures will become apparent over time, but action is necessary to minimize the adverse consequences of the crisis which has dominated the region since 1997.  相似文献   
37.
<正>(上接2014年第5期)1.2在EXCEL中建立数学公式按上述装配关系,在EXCEL中建立数学公式,逐项输入计算所需的各项参数(均为相关部品的结构尺寸参数及装配要求参数等,表中所列数据仅为计算示意),得到表1所示的计算表(计算公式略)。表中,序号26中的拉杆长度为初设值,系统自动计算出初设拉杆长度的理论露出长度,调整拉杆的初设长度,使拉杆理论露出长度近似等于规定值(后续通过公差计算,确定此处最佳的规定值),即可得到拉杆的理论长度。  相似文献   
38.
Introduction The scarcity of available radio spectrum limits theextension of the modern wireless communication. Oneapproach to alleviate this limitation is the dynamicspectrum allocation (DSA) at network level, which isable to adapt to the spatial and temporal variation intraffic load[1]. The concept of DSA was first presentedin the DARPA (Defense Advanced Research ProjectsAgency) XG Program[2], with the aim to increase thespectral efficiency by spectrum sharing among radios.Due to the…  相似文献   
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