加拿大3S技术的发展和应用

介绍了3S技术在加拿大的发展和应用情况.地理信息系统是空间信息管理的平台,在政府和许多行业中有广泛的应用,在互联网上掀起了电子地图和位置搜索的应用浪潮.遥感技术是信息采集的重要手段,在数据处理技术方面不断进步,广泛应用于城市和环境研究.全球定位系统是空间定位的重要工具,包括导航GPS和测量GPS两大应用领域.3S技术的综合应用,推动着一种以空间信息服务为特征和载体的产业G-business正在形成.     

Application of a contribution to sustainability test by the Joint Review Panel for the Canadian Mackenzie Gas Project

Ultimately, the enhancement we need to deliver through environmental assessment is confidence that every approved undertaking will move us positively towards a desirable and durable future. In Canada, the most promising steps in this direction have been in several major project assessment reviews with public hearings and independent panels that applied a contribution to sustainability test. The most recent and advanced case is the review of a proposed C$16.2 billion natural gas infrastructure undertaking in the Northwest Territories. The Panel's application of the contribution to sustainability test compared the cumulative effects, equity and legacy implications of a range of project pace and scale alternatives. The Panel concluded that the project would offer positive overall contributions only if 176 recommendations were implemented. While the Panel's process was slow and the governments accepted only the most modest recommendations, the Panel's review set a new standard of analytical practice. This paper examines how the review was done and assesses its strengths and limitations, with particular attention to the design and application of the contribution to sustainability test.     

Large multifunctional suburban centres and the transformation of the suburban realm

ABSTRACT

The paper contributes to the present reflection on the transformation of the suburb by investigating the capacity of large multifunctional suburban centres (LMSCs) to provide public transit- and walking-conducive environments within the suburban realm. To this end, it investigates land-use and commuter journey patterns of the 13 largest suburban multifunctional centres in Canada. The study exposes difficulties in using LMSCs as recentralization instruments meant to “urbanize” the suburb by making it more public transit- and walking-oriented. It points to tensions within LMSCs between playing the role of activity centre and adopting land-use configurations conducive to public-transit use and walking. The stronger is the centrality role of an LMSC, the more it is overtaken by automobiles from its dispersed suburban surroundings. Alternatively, LMSCs can generate weak centrality effects while performing as effective transit-oriented developments. The paper concludes by highlighting difficulties in overcoming suburban transportation and land-use path dependencies.     

成功的旧建筑革新——加拿大多伦多市女王港旧仓库改建项目

加拿大蔡德勒·罗伯茨建筑师事务所将多伦多 市女王港的旧有仓库改建成为一个综合性商业中心，创造了全新而富有魅力的建筑环境。其成功的经验表明旧建筑革新再利用既可以取得可观的经济和环境效益 ，也有益于保持城市的固有文脉 ，要实现这一点需要各方面的理解和支持，也需要建筑师的聪明才智。     

Field Investigation on the First Bridge Deck Slab Reinforced with Glass FRP Bars Constructed in Canada

Recently, there has been a rapid increase in using noncorrosive fiber-reinforced polymers (FRP) reinforcing bars as alternative reinforcement for bridge deck slabs, especially those in harsh environments. A new two-span girder type bridge, Cookshire-Eaton Bridge (located in the municipality of Cookshire, Quebec, Canada), was constructed with a total length of 52.08 m over two equal spans. The deck was a 200-mm-thick concrete slab continuous over four spans of 2.70 m between girders with an overhang of 1.40 m on each side. One full span of the bridge was totally reinforced using glass fiber-reinforced polymer (GFRP) bars, while the other span was reinforced with galvanized steel bars. The bridge deck was well instrumented at critical locations for internal temperature and strain data collection using fiber optic sensors. The bridge was tested for service performance using calibrated truckloads as specified by the Canadian Highway Bridge Design Code. The construction procedure and field test results under actual service conditions revealed that GFRP rebar provides very competitive performance in comparison to steel.     

加拿大东部出现世纪冰雨

介绍了解１９９８ 年１ 月加拿大东部地区特大冰灾概况。     

Short-Term Traffic Prediction on Different Types of Roads with Genetically Designed Regression and Time Delay Neural Network Models

Research for advanced traveler information systems (ATIS) has been focused on urban roads. However, research for short-term traffic prediction on all categories of highways is needed, as highway agencies expect to implement intelligent transportation systems across their jurisdictions. In this study, genetic algorithms were used to design time delay neural network (TDNN) models as well as locally weighted regression models to predict short-term traffic for six rural roads from Alberta, Canada. These roads are from various trip-pattern groups and functional classes. Refined TDNN models developed in this study can limit most average errors less than 10% for all study roads. Refined regression models show even higher accuracy. Average errors for the refined regression models are less than 2% for roads with stable patterns. Even for roads with unstable patterns, average errors are below 4%, and the 95th percentile errors are less than 7%. It is believed that such accurate predictions would be useful for highway agencies to implement statewide ATIS.     

基于“3S”技术的加拿大“一枝黄花”空间分布研究

近几年来，加拿大一枝黄花在宁波疯狂蔓延，影响生物多样性，破坏生态平衡，造成巨大的危害。弄清加拿大一枝黄花在某一地区的空间分布，是采取各种防治措施的前提。以“3S”技术为依托，将一枝黄花的分布区类比于土地监测中的地类图斑，通过对遥感影像的处理，确定一枝黄花的空间分布地域，利用GIS软件矢量化出它的地类图斑，再针对这些地类图斑进行调查，从整体上确定一枝黄花在该地区的属性特征，并以该理论为指导，以“3S”技术为基础研究加拿大一枝黄花分布的理论模型。     

Association between vascular access type and patient mortality among elderly patients on hemodialysis in Canada

Optimal vascular access in elderly patients requires consideration of the benefits and risks in a population with increased comorbidity and mortality. Our objective was to examine the association between vascular access type and patient mortality by age category among incident adult hemodialysis patients registered in the Canadian Organ Replacement Register between 2001 and 2010. We also describe the secular trend in incident and prevalent vascular access use. We used a Cox proportional hazards model to evaluate the overall mortality in patients aged less than 65, 65–74, 75–85, and greater than 85 years who initiated hemodialysis using a central venous catheter (catheter) or arteriovenous (AV)‐access (fistula or graft) using an intention‐to‐treat approach. The cohort of 39,721 patients consisted of 42%, 27%, 26%, and 5% of patients aged <65, 65–74, 75–85, and >85, respectively. Patients who initiated hemodialysis using an AV‐access constituted 21%, 22%, 20%, and 15% of each age category. AV access use was associated with lower adjusted mortality compared with catheter use in each age category (Hazard Ratios [HR], 0.67; 95% Confidence Interval [0.62–0.72]; HR, 0.76 [0.63–0.91]; HR, 0.77 [0.64–0.93], HR, 0.73 [0.56–0.96], respectively). In Canada, use of an AV‐access is associated with lower mortality across all age categories, even in the very elderly. Further studies are required to understand the patient preference, complications, and resource use when selecting access type in the elderly.