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11.
根据我国已建成通车的高等级公路的使用情况,从路基施工前准备、路基施工、台背处理、路面施工及路表面排水处理等方面较全面地分析了水泥混凝土路面破坏的原因及其防治。  相似文献   
12.
我国基金选股选时能力实证分析   总被引:3,自引:0,他引:3  
本文运用西方基金绩效评价中较为常见的选股选时能力模型及其FF3改进模型对我国证券投资基金进行实证研究,在处理过程中考虑了不同取样频率和不同样本区间的影响.研究结果表明:(1)我国基金只存在很小程度的选股能力,而基本不存在选时能力,更没有基金同时具有选时能力和选股能力;(2)多因素改进模型与原模型相比显著提高了解释能力,说明在可能的情况下应尽可能使用多因素模型;(3)加快取样频率后基金表现出更强一些的选股能力,但在各年度内基金的选股能力有所差异.  相似文献   
13.
毕明丽 《价值工程》2014,(19):135-136
地质勘测工程具有复杂、要求高的特点,本文从工程地质勘测出发,对其勘测方法、勘测原则作出了分析,重点探讨了地质勘测施工各阶段需要控制的要点,具有一定的借鉴效果。  相似文献   
14.
Deaths, injuries and disabilities resulting from road traffic injuries (RTIs) are a public health major concern. This study aims to calculate the burden of RTIs in Kermanshah Province in Iran. In this study to determine the years of life lost (YLL) related to RTIs, the National Death Registration and Forensics Medicine census data were employed. We use forensic medicine data to calculate the incidence of non-fatal injuries and years lost due to disability (YLD). The cause of death and non-fatal injuries was classified using ICD-10 codes and 23 groupes of global burden of diseases (GBD) 2010. The disability-adjusted life year (DALY) estimated on the guidelines of the GBD 2010 and age and sex structure was taken from the National Statistic Center for the year 2010. Overall, 70.8% of the subjects were males. The fatal and non-fatal injury rates of RTI were 51.3 and 283.6 per 100,000 persons, respectively. YLLs and YLDs were 46613 (24.5 per 1000) and 3405 (1.8 per 1000) in both sexes, respectively. The disability adjusted life years were 40711 in males, 9306 in females and 50018 in both sexes (42.5, 9.8 and 26.3 per 1000, respectively). More than 93% of DALY was from YLL (24.5 per 1000), with a small proportion for YLD (1.8 per 1000). Accounting for more than 50,000 DALY attributed to RTIs, traffic injuries is a major public health and socioeconomic problem in Kermanshah. Designing cost-effective interventions based on comprehensive and multi-sectoral programmes at the national and provincial levels can save many lives and resources that are lost every year. Undoubtedly, establishing a surveillance system at the sub-national level and measuring the burden of injuries, as in this study, can help policy-makers and planners in lessening the burden of RTIs.  相似文献   
15.
李杨 《价值工程》2014,(29):102-103
本文通过理论与实践知识结合,结合交通工作经验,深度挖掘农村公路建设中存在的问题,并就如何坚持科学发展观,推动农村公路健康发展的有效对策进行探讨。  相似文献   
16.
孔海东  张培  刘兵 《技术经济》2019,35(6):99-108
通过文献调查并结合案例的描述性分析,提出数字技术时代价值网络中不同行为主体之间的赋能内涵、关键维度以及基于赋能跨层次效应的价值共创行为分析框架。将"赋能氛围""主体赋能"分别作为价值网络中赋能的宏观维度和微观维度进行概念化。界定了两个维度的关键组成要素,分别包括信息共享、开放性结构、协同规则以及主体关系、资源整合和影响。构建了赋能的跨层次效应模型,分析了赋能的宏观-微观跨层次效应及其对价值网络生态和主体价值创造的影响。  相似文献   
17.
围绕数据组织、数据的联动检索技术、Excel高级函数、Excel自定义函数、Excel VBA程序的开发过程,系统地建立了基于Excel的道路工程计算的框架模板。  相似文献   
18.
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   
19.
This study analysed motorcycle crashes in Spain. Ninety-nine thousand three hundred and four motorcycle crash reports filed in the years 2006–2011 were extracted from the Directorate General of Traffic database of crashes with victims. These data were analysed in terms of gender, age groups, trip purpose, type of crash, speed violation, day of the week, harm caused, use of helmet and psychophysical conditions of the driver to study the characteristics of motorcycle crashes in Spain and to assess the differences between male and female motorcycle drivers in these crashes. Significant differences were found in all the variables considered in the study, which implies gender differences in the profile of the injured motorcycle driver. The severity of motorcycle crashes suffered by male drivers is higher than that of women. These results corroborate the need to develop measures differentiated by gender, based on their profile.  相似文献   
20.
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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