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131.
Trip generation of vulnerable populations in three Canadian cities: a spatial ordered probit approach 总被引:1,自引:0,他引:1
Matthew J. Roorda Antonio Páez Catherine Morency Ruben Mercado Steven Farber 《Transportation》2010,37(3):525-548
This paper provides an analysis of trip generation of three vulnerable groups: single-parent families, low income households,
and the elderly. It compares the mobility of these groups to that of the general population in three Canadian urban areas
of Hamilton, Montreal and Toronto, based on data from large-sample metropolitan transport surveys. An ordered probit model
with spatially expanded coefficients is used for the analysis. Spatial expansion shows that there are spatial mobility trends
for elderly populations and low-income populations even after socio-economic attributes are accounted for. Such spatial differences
are not generally found for single parent families. This novel spatial analysis provides clues as to where vulnerable populations
may experience greater degrees of social exclusion. It provides information to help prioritize transportation infrastructure
projects or other social programs to take into account the needs of vulnerable populations with the lowest levels of mobility. 相似文献
132.
133.
介绍海上平台生活楼HVAC系统通风管线下送风气流组织设计,其中,海上平台生活楼HVAC系统通风管线设计引用某平台生活楼详细设计及加工设计,下送风气流组织设计是在建造结束并在海上调试后,对每个房间内部通风效果和舒适性的思考及总结. 相似文献
134.
135.
测定了30例二尖瓣脱垂综合征伴室性心律失常患者的QTd。结果发现,二尖瓣脱垂组QTd、QTcd、JTd显著延长,说明心室肌复极有局部的不均一性和电不稳定性,离散度与室性心律失常的发生密切相关,可能是室性心律失常发生的机理之一。QTd不仅能预测室性心律失常及猝死,而且能指导临床用药,是一很好的临床观察指标。 相似文献
136.
A country can adopt one of two standards for traffic flow — cars may travel on the left or right side of the road. When drivers
who are accustomed to driving on the right side of the road drive on the left side, and vice versa, the mental workload is
likely increased due to the driver’s unfamiliarity with a new language, the position of the driver’s seat, different driving
directions, and other factors that differ from those of their home country. One method of doing this is to make sure that
the in-vehicle route guidance information (RGI) is not overly complicated — thereby assisting drivers in improving their safety.
Consequently, the aim of this study was to facilitate mobility and improve safety for natural right-side drivers driving temporarily
in left-side traffic. In this study, driver behavior and workload — given various types of RGI — were evaluated in a driving
simulator with a variety of prescribable test conditions. This research was composed of two experiments. In the first, various
types of in-vehicle route guidance systems were tested and evaluated in terms of their characteristics and associated driver
behaviors (while driving). In the second experiment, systemic factors and effectiveness were evaluated by two combined systems,
arrow and map-type information, based on the results of the first experiment. In light of both experiments, the various types
of route guidance systems were discussed in terms of their results. A navigation system was proposed to alleviate some of
the secondary tasks such as route selection. 相似文献
137.
Jiuh-Biing Sheu Stephen G. Ritchie 《Transportation Research Part C: Emerging Technologies》1998,6(5-6)
In this paper, a new methodology is presented for real-time detection and characterization of incidents on surface streets. The proposed automatic incident detection approach is capable of detecting incidents promptly as well as characterizing incidents in terms of time-varying lane-changing fractions and queue lengths in blocked lanes, lanes blocked due to incidents, and incident duration. The architecture of the proposed incident detection approach consists of three sequential procedures: (1) Symptom Identification for identification of incident symptoms, (2) Signal Processing for real-time prediction of incident-related lane traffic characteristics and (3) Pattern Recognition for incident recognition. Lane traffic counts and occupancy are the only two major types of input data, which can be readily collected from point detectors. The primary techniques utilized in this paper include: (1) a discrete-time, nonlinear, stochastic system with boundary constraints to predict real-time lane-changing fractions and queue lengths and (2) a pattern-recognition-based algorithm employing modified sequential probability ratio tests (MSPRT) to detect incidents. Off-line tests based on simulated as well as video-based real data were conducted to assess the performance of the proposed algorithm. The test results have indicated the feasibility of achieving real-time incident detection using the proposed methodology. 相似文献
138.
A multinational company uses a personal computer to schedule a fleet of coastal tankers and barges transporting liquid bulk products among plants, distribution centres (tank farms), and industrial customers. A simple spreadsheet interface cloaks a sophisticated optimization-based decision support system and makes this system useable via a varity of natural languages. The dispatchers, whose native language is not English, and some of whom presumably speak no English at all, communicate via the spreadsheet, and view recommended schedules displayed in Gantt charts both internationally familiar tools. Inside the spreadsheet, a highly detailed simulation can generate every feasible alternate vessel employment schedule, and an integer linear set partitioning model selects one schedule for each vessel so that all loads and deliveries are completed at minimal cost while satisfying all operational requirements. The optimized fleet employment schedule is displyed graphically with hourly time resolution over a planning horizon of 2-3 weeks. Each vessel will customarily make several voyages and many port calls to load and unload products during this time. 相似文献
139.
140.
Spatial fisheries ecology: Recent progress and future prospects 总被引:1,自引:0,他引:1
L. Ciannelli P. Fauchald K.S. Chan V.N. Agostini G.E. Dingsr 《Journal of Marine Systems》2008,71(3-4):223
We review recent progresses made in the study of fish distribution and survival over space — i.e., fisheries spatial ecology. This is achieved by first surveying the most common statistical approaches and relative challenges associated with the analysis of fisheries spatial data, loosely grouped in geostatistical and regression approaches. Then we review a selected number of case-studies implementing the discussed techniques. We conclude by proposing new areas of statistical and ecological research to further our understanding of how fish distribute and survive in space. This review serves a dual purpose by emphasizing the scientific importance of studying spatial interactions to better understand the temporal dynamics of fish abundance, and by promoting the development of new analytical and ecological approaches for the analysis of spatial data. Through our survey we cover different statistical techniques, marine ecosystems and life stages. This analytical, geographic and ontogenetic variety is also purposely selected to highlight the importance of comparative and multidisciplinary studies across diverging ecological disciplines, ecosystems and life stages. Besides having a general ecological relevance this review also bears a more applied significance, owing to the increasing need for protecting renewable marine resources along with their primary habitat. 相似文献