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排序方式: 共有1004条查询结果,搜索用时 15 毫秒
1.
We examined 2007, 2010, 2012, 2014, and 2016 data from 49 countries to determine changes wrought by China’s Belt and Road initiative; we also used panel data regarding the Maritime Silk and Inland Silk Roads to test initiative effects on Chinese exports. Post-initiative infrastructure expansion and logistics performance improvements led to positive effects on China’s exports. Additionally, legal-system similarities and inland borders with trade partners had a more positive effect on Chinese exports in the Inland Silk Road, while population and free trade agreements were found to have a more positive effect on the Maritime Silk Road.  相似文献   
2.
Distance functions are increasingly being augmented, with environmental goods treated as conventional outputs. A common approach to evaluate the opportunity cost of providing an environmental good is the exploitation of the distance function's dual relationship to the value function. This implies that the opportunity cost is assumed to be non‐negative. This approach also requires a convex technology set. Focusing on crop diversification for a balanced sample of 44 cereal farms in the East of England for the years 2007–2013, this paper develops a novel opportunity cost measure that does not depend on these strong assumptions. We find that the opportunity cost of crop diversification is negative for most farms.  相似文献   
3.
The One Belt One Road (OBOR) project is perhaps China's most significant international relations initiative in recent times. It is based on openness, harmony, inclusivity, mutual benefit and market operations and aims to connect the economically vibrant East Asia and the developed Europe by land and by sea, and in the process, it brings growth and development to tens of countries along the modern Silk routes. In this paper, we compare the impact of the main initiatives of OBOR, namely enhancements in physical infrastructure and improvements in border administration, on the trade of countries that have signed on to this project, especially countries along the six economic corridors. We find overwhelming evidence that shows improvements in border administration has the greatest impact on exports of corridor countries. Although physical infrastructure is important for trade, the Chinese government should place equal attention to improvements in trade facilitation to ensure trade routes operate seamlessly across the various corridors.  相似文献   
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5.
This study assesses the impact of traffic sign deficit on road traffic accidents in Nigeria. The participants were 720 commercial vehicle drivers. While simple random sampling was used to select 6 out of 137 federal highways, stratified random sampling was used to select six categories of commercial vehicle drivers. The study used qual-dominant mixed methods approach comprising key informant interviews; group interviews; field observation; policy appraisal and secondary literature on traffic signs. Result shows that the failure of government to provide and maintain traffic signs in order to guide road users through the numerous accident black spots on the highways is the major cause of road accidents in Nigeria. The study argues that provision and maintenance of traffic signs present opportunity to promoting safety on the highways and achieving the sustainable development goals.  相似文献   
6.
Cycling-inclusive urban planning is attracting attention worldwide because of the environmental, health, economic, and transport benefits inherent to cycling from the individual and the societal perspectives. The Czech Republic is one of the emerging cycling countries that are trying to promote and support cycling, but cycling mode shares are low because of the poor quality of the scarce infrastructure and the psychological barrier of the perceived lack of safety when cycling in mixed traffic. This study takes a multimodal approach based on the Theory of Planned Behaviour and focuses on the factors underlying the willingness to share the road from the perspective of cyclists and drivers: positive attitudes toward cycling, positive attitudes toward cyclists’ behavior, social norms toward cycling and anxiety to share the road. A web-based questionnaire was tailor-designed and administered in the Czech Republic via social networks, web forums, and the Civinet network, and a hybrid bivariate-ordered model tested the behavioral framework. Results show that the willingness to share the road as a cyclist or as a driver relates positively to positive attitudes towards cycling and cyclists’ behavior, and negatively to the anxiety of sharing the road. Moreover, mediator effects are observed and a clear relation emerges between the experience on the road as both a cyclist and a driver on the willingness to share the road as a cyclist. Lastly, results show that the factors underlying road sharing intentions are related significantly to gender, travel habits, and perceived personal and infrastructure-related barriers to cycling.  相似文献   
7.
This study aimed to identify the roles of laypeople at road traffic injuries (RTIs). A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The key words of ‘laypeople’, ‘layman’, ‘layperson’, ‘bystander’, ‘first responder’, ‘lay first responder’, ‘road traffic’, ‘road traffic injury’, ‘crash injury’, ‘crash scene’, ‘emergency’, ‘trauma care’, and ‘prehospital trauma care’ were used in combination with the Boolean operators OR and AND. We did electronic search on Google Scholar, PubMed, ISI Web of Science, CINAHL, Science Direct, Scopus, ProQuest. Based on the reviewed studies, some factors such as cultural conditions, knowledge, relief agencies, and demographic factors affect the interventions of laypeople at the crash scene in functional areas. Regarding the permanent presence of people at the crash scene, the present study can provide an opportunity to reduce different side effects of RTIs imposed on the society.  相似文献   
8.
本文基于预期功能安全,采用功能分解方法,总结出部分车辆自动紧急制动(AEB)系统失效和误作用场景,并从中选取典型场景作为测试场景,开展不同车型的实车道路试验,总结出AEB系统的缺陷与隐患分类。希望此类研究能为AEB系统失效和误作用测试标准的制定提供参考。  相似文献   
9.
通常,道路桥梁的施工难度较高,其中涵盖的内容较多,如技术管理、预算管理、成本控制等。这些因素使道路桥梁的施工变得更为困难,施工的复杂性和综合性更加突出。在桥梁的施工过程中,存在着许多风险,所以需要做好施工监理工作,从而最大限度地保障施工过程中不会出现任何故障和问题。因此,加强道路桥梁施工监理至关重要。论文从道路桥梁施工的角度,探究和分析如何做好相关的监理工作。  相似文献   
10.
Abstract

Over the past four decades considerable efforts have been taken to mitigate the growing burden of road injury. With increasing urbanisation along with global mobility that demands not only safe but equitable, efficient and clean (reduced carbon footprint) transport, the responses to dealing with the burgeoning road traffic injury in low- and middle-income countries has become increasingly complex. In this paper, we apply unique methods to identify important strategies that could be implemented to reduce road traffic injury in the Asia-Pacific region; a region comprising large middle-income countries (China and India) that are currently in the throes of rapid motorisation. Using a convolutional neural network approach, we clustered countries containing a total of 1632 cities from around the world into groups based on urban characteristics related to road and public transport infrastructure. We then analysed 20 countries (containing 689 cities) from the Asia-Pacific region and assessed the global burden of disease attributed to road traffic injury and these various urban characteristics. This study demonstrates the utility of employing image recognition methods to discover new insights that afford urban and transport planning opportunities to mitigate road traffic injury at a regional and global scale.  相似文献   
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