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21.
Exposure to fine particulate matter from vehicle exhaust is associated with increased health risk. This study develops a new approach for creating spatially detailed regional maps of fine particulate matter concentration from vehicle exhaust using a dispersion model to better evaluate these risks. The spatial extent, diurnal, and seasonal patterns of concentration fields across Los Angeles County, California are evaluated and population exposure and exposure equity by race and income are investigated. The results demonstrate how this modeling approach can create new knowledge about vehicle emissions exposure. This approach also provides a method for proactively screening out regional plans, or specific projects within these plans, that are likely to cause air quality concerns. A proactive and regional air quality assessment can identify potential problems earlier in the planning process and a wider range of solutions, saving time, money and protecting public health. The detailed concentration maps can also be used to improve the siting of regulatory air quality monitors and provide more accurate exposure data for epidemiology studies.  相似文献   
22.
文中指出了小曲率、薄壁感应热煨弯管前过渡区出现的成型问题,分析感应加热弯曲时前过渡区的受力状况和变形稳定性,从加强前过渡区钢管热弯曲时的稳定性出发,设计了伸缩自如、支撑力大、自身质量轻、装卸方便、通用性强的前过渡区支撑器。由应用前后的对比可知,前过渡区出现的问题得到根本解决。  相似文献   
23.
As a response to profoundly poor air quality and associated environmental justice concerns in the San Joaquin Valley region in California, the Tune In & Tune Up (TI&TU) program provides residents with free vehicle emissions testing and vouchers for smog repair. We used data on approximately 19,000 repaired TI&TU vehicles from 2012 to 2018, and several estimation techniques, to quantify a range of nitrogen oxides (NOX) emissions prevented as a result of the program. We then calculated resulting mortality impacts from reduced exposure to fine particulate matter (PM2.5) in the form of secondary nitrates. After applying a novel smog repair emissions abatement depreciation function, we find that six years of operation of the TI&TU program has reduced NOX emissions by approximately 53–302 tons by the end of 2018. Using a concentration response function for ambient PM2.5, we found that between 0.055 and 0.31 premature deaths have also been avoided. We present multiple methods for assessing public health impacts, which can be used as guidance for evaluating similar transportation-based emission reduction programs.  相似文献   
24.
国内外的普遍服务政策中存在许多重要的理论和实践问题。普遍服务政策实际上是一个经济与社会发展问题.本文选择了道路交通中的信息服务的几个方面,讨论了在我国当前发展水平下,如何对大多数出行者进行服务和有关政策问题.文中首先对道路交通信息服务进行了界定,简要介绍了国内城乡道路交通信息服务的状况和存在的问题,然后就道路交通信息服务的发展与普遍服务展开了讨论.通过国内外经济发展和道路交通情况的对比,得出了目前我国道路交通发展水平基本相当于发达国家20世纪60年代末到70年代的判断.由此提出:由于我国道路交通和运输仍然处在初期,这使得我国在信息化浪潮中面临着“数字鸿沟”和用信息化带动工业化的矛盾;但是民众的出行效率和方便程度是政府的责任,民众有权要求得到方便和便宜的道路交通信息服务.因此,政府在设计和安排道路交通信息系统时,应本着实事求是和执政为民的原则,将主要注意力集中到为大众服务的领域.为乘坐公共交通工具的出行者提供价格低廉的,甚至是免费的信息服务.最后从发展是一个动态过程的角度出发,提出应该辩证地看待不同的利益和效率,处理好先走一步和公平的问题.  相似文献   
25.
介绍了国内外交通事故救援现状,重点分析了我国道路救援系统存在的问题,并从将道路交通救援工作依托于城市紧急救助系统、加强事故现场交通管制、强化黄金1小时救护制和对交通事故救援预案重新分级等四个方面提出了改善我国道路交通事故紧急救援的对策。  相似文献   
26.
针对炭质千枚岩隧道施作锚杆时容易剥落掉块并导致局部失稳的问题,对先喷后锚法与传统先锚后喷法进行比较研究。为了分析2种施工方法对围岩与支护体系力学响应的影响,借助三维数值分析手段对洞周位移变化、初期支护结构受力、锚杆受力及围岩的塑性发展进行分析。结果表明,先喷后锚法引起的围岩变形与支护体系应力略大,先锚后喷法对控制围岩变形效果显著,二者均可满足一般工程需要;当对围岩变形控制要求严格时应选用先锚后喷法。  相似文献   
27.
人类对于正义及其标准的探讨由来已久,不过,在当代政治学理论界中最具影响的正义理论莫过于罗尔斯的正义理论。从《正义论》到《政治自由主义》,罗尔斯在对古典功利主义正义观批判的基础上提出了基于两大正义原则的正义理论。本文评析了罗尔斯正义理论的突破意义,总体介绍了《正义论》的主要观点。  相似文献   
28.
Abstract

Multi-purpose marine protected areas (MPAs) are prevalent world-wide as institutional mechanisms deployed in the marine environment to manage multiple uses, conserve resources and protect ecosystems. Yet some people may experience disadvantage following the implementation of new MPAs. One understudied aspect of MPAs is the distribution of advantages and disadvantages and how best to address the “justice” concerns that they raise. This article identifies a framework of principles, methods and tools to address these concerns. It devises a “MPA justice model” and demonstrates its applicability to a Taiwanese case study. In 2014, Taiwan proclaimed its first multiple-purpose MPA, the South Penghu Marine National Park and the case study shows ways that the MPA’s socio-economic sustainability could have been better accomplished. The article focuses on future MPA establishment that incorporates distributional fairness and procedural legitimacy into MPA site designation and zoning design - but might also be adapted to use retrospectively in MPA review processes.  相似文献   
29.
Abstract

Engineering bridges the gap between, on the one hand, that mix of philosophy and politics that we call policy and, on the other, the physical implementation of the means to put policy into practice. Starting with a brief outline of the nature of accessibility, why it is important and how in some cases a person might be disabled by a lack of accessibility, this article – based on the author's Inaugural Lecture given at University College London in February 2005 – turns to consider how a person's needs challenge their capabilities (i.e. what they can do) and considers a radical approach to understanding people's capabilities in the implementation process. Next, the formation of policy intentions in order to permit, encourage and implement the engineering of appropriate solutions is discussed and conclusions drawn about how this affects work in the transport domain. Perhaps we need to look at the world in a different way before we can make it a better place.  相似文献   
30.
为了运用应变能密度方法对黄土滑坡进行临滑预报,通过假定黄土为近似弹性体,以发生剪切破坏时的最大抗剪强度与临滑时最大应变的乘积作为最大应变能密度。同时以实际观测的位移-时间变量之间的关系,用回归法拟合出应变-时间关系的表达式,并得出应变能-时间的表达式。用应变能密度法对黄茨滑坡进行了临滑预报,并与滑坡的实际发生时间作了对比,两者非常接近。应用应变能密度法可对黄土滑坡进行较为准确的临滑预报。  相似文献   
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