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61.
Recent years have witnessed a growing volume of papers describing the use of GPS technology and other tracking technologies for obtaining data on time–space activities. These methods have several advantages over traditional methods of time–space data collection in terms of accuracy, resolution and length of the possible data collection period. However, to date, no work has been done on the compliance rates among participants and the resulting validity of the collected data. This paper presents a method that combines the use of a GPS receiver with Radio Frequency Identification (RFID) technology that was implemented in research on time–space activities of elderly persons with cognitive impairment. The method presented in this paper enables monitoring the level of compliance of the participants during their participation in the study and presents a unique opportunity to examine the extent to which participants in a GPS based study are able to comply with study requirements. Healthy older adults and those with cognitive decline were found to be generally compliant with a complex study protocol. These results serve as another step into the acceptance of GPS based studies as a valid methodology for mobility data collection.  相似文献   
62.

An integrated method for benthic habitat assessment is described, in which divers maneuver boards equipped with digital video, temperature, and depth recorders while being towed behind a small boat. The tow path is concurrently recorded by a GPS receiver, and a layback model is applied to more accurately map the data. Percent cover of salient benthic categories is quantified by whole-image analysis of still frames sampled at 30-s intervals. The results of 15 towed-diver surveys at Midway Atoll in the Hawaiian Archipelago during a mass coral bleaching event are presented to exemplify the method and are compared to results derived from conventional methods. Towed-diver surveys bridge a gap between large-scale mapping efforts using satellite data and small-scale, roving diver assessments, providing a mesoscale spatial assessment of reef habitats. The spatial coverage of towed-diver surveys provides comprehensive data to managers concerning the extent, intensity, differential taxonomic response, and bathymetric correlates of bleaching.  相似文献   
63.
64.
Based on 2001-census data for Belgium, energy consumption levels for commuting were calculated and mapped on the basis of residential locations in the administrative regions of Flanders and Brussels. Comparison with regional differentiations in commuting distances, modal shares of non-car travel modes and aspects of infrastructure and population densities clarifies some relationships between energy consumption, commuting behaviour and spatial-economic structure in the suburbanised historic–polycentric spatial structure which characterises the northern part of Belgium. It is found that mode choice appears to be of little impact for the energy performance of home-to-work travel on the scale of the Flanders region. At the other hand, proximity between home and work locations is paramount.Residential density plays a part in this, although much depends on the specific situation. This is also the case for the accessibility of the main road and rail network. In some regions these infrastructures induce long-distance commuting, whereas in the economic core areas this effect is much less pronounced. All these are factors that are very much determined by infrastructural and spatial policies of the past.  相似文献   
65.
一年一度的美国中部地区卡车展览会(Mid America Truck Show)于今年3月19~21日在肯塔基州路易斯维尔如期举行.康明斯展出了全系列满足EPA2010排放标准的中马力(6.7、8.3和9升)和重型柴油机(11.9升和15升)产品。  相似文献   
66.
康明斯连续第二年入选《财富》“全球最受尊敬企业”排行榜 《财富》杂志日前公布了2009年度“全球最受尊敬企业(World’s Most Admired Companies)”排行榜,康明斯公司连续第二年入选,是唯一一家上榜的柴油机公司。  相似文献   
67.
Stated preferences for investigating commuters' diversion propensity   总被引:4,自引:0,他引:4  
A reasonable response to increasing traffic congestion may come from the rapidly developing traveler information systems. Such systems may be successful if they effectively influence drivers' enroute decisions; in this regard, a critical factor may be commuters' willingness to divert from their regular route in response to information about traffic congestion. This study evaluates the effects of real-time traffic information along with driver attributes, roadway characteristics and situational factors on drivers' willingness to divert.The empirical portion of this study is based on a survey of downtown Chicago automobile commuters. The stated preference approach was used to study commuters' diversion propensity. Drivers expressed a higher willingness to divert if expected delays on their usual route increased, if the congestion was incident-induced as opposed to recurring, if delay information was received from radio traffic reports compared with observing congestion, and if trip direction was home-to-work rather than work-to-home. Respondents were less willing to divert if their alternate route was unfamiliar, unsafe or had several traffic stops. Socioeconomic characteristics were also significant in predicting willingness to divert.  相似文献   
68.
2008年6月11日,随着无锡康明斯涡轮增压技术公司(原无锡霍尔塞特)二期新厂房正式落成、无锡范尼韦尔工程公司开业投产以及康明斯涡轮增压技术系统新技术中心正式揭牌.康明斯涡轮增压技术系统(康明斯公司全资子公司)在华本地生产和研发能力得到新的提升。  相似文献   
69.
尽管于2007年1月1日开始在美国正式实施的全球最为严格的机动车排放法规EPA2007,给北美重卡和发动机行业带来了很大的压力,但更加严格的EPA2010排放标准却已经成为了那些在行业具有领导地位的发动机企业全力攻关的方向.  相似文献   
70.
As the proliferation of e-commerce leads to ever greater numbers of on-line transactions, transportation planners are interested in the impacts of e-shopping on our strained transportation systems. Although the substitution effect of e-shopping is appealing, previous studies provided mixed results on its impact. Using 539 adult internet users in the Minneapolis-St Paul metropolitan area, this study applied a structural equations model to investigate the interactions among online purchases, in-store shopping, and product information search via internet. We found that online searching frequency has positive impacts on both online and in-store shopping frequencies and online buying positively affects in-store shopping. In particular, the marginal effects of online-buying frequency and online-searching frequency on in-store shopping frequency were estimated at 0.153 and 0.189, respectively. Since the internet as a shopping channel tends to have a complementary effect on in-store shopping, the rise of e-shopping is not likely to be a solution but a challenge to travel reduction.  相似文献   
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