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1.
The United Nations Watercourses Convention entered into force on 17 August 2014, following a long and complex journey that dates back to 1970 when the UN referred the matter to its legal arm, the International Law Commission. This article follows the Convention through that long and turbulent road, examines its main provisions and analyses the reasons for the delay of its entry into force. It concludes by answering the question of why entry into force of the Convention should indeed matter.  相似文献   
2.
美国21世纪前期的军事战略重点将是争夺外空优势,夺取制天权和制信息权。分析了美国夺取外空优势的原因,及其为夺取外空优势在国家政策、航天发展和技术准备等方面采取的措施。  相似文献   
3.
本文所讲述的是美国国家公园服务中心在评估申请提案、制定审查方案过程中所应用的各种标准和准则 ,同时也列出了一些认识、保护未列入国家公园体系中其他重要资源的途径和方法。  相似文献   
4.
Routine inspection is the most common form of highway bridge inspection to satisfy the requirements of the National Bridge Inspection Standards. The accuracy and reliability of documentation generated during these inspections are critical to the allocation of Department of Transportation construction, maintenance, and rehabilitation resources. Routine inspections are typically completed using only the visual inspection technique and rely heavily on subjective assessments made by bridge inspectors. In light of this, and given the fact that visual inspection may have other limitations that influence its reliability, the Federal Highway Administration initiated an investigation to examine the reliability of visual inspection as it is currently applied to bridges in the United States. This paper will summarize results from this study related to the accuracy and reliability of routine inspection documentation. A number of important conclusions were developed from the experimental study. Generally, it was found that all structural condition documentation is collected with significant variability. Specifically, 95% of primary element condition ratings for individual bridge components will vary within two rating points of the average and only 68% will vary within one point. Documentation generally collected to support condition ratings also has significant variability as exemplified by the number and types of field notes and photographs taken by inspectors. With respect to the use of element-level inspections, it was found that element usage was generally consistent with the Commonly Recognized Element Guide. However, there is significant variability in the condition state assignments of those elements and in some cases the condition states are not applied correctly to particular elements.  相似文献   
5.
美国节能管理工作特点及对我国的启示   总被引:5,自引:1,他引:4  
翟青  康艳兵  牛波 《中国能源》2003,25(7):7-13
本文比较系统地分析了美国节能管理工作的主要特点,并研究了美国的节能管理模式对我国推动节能工作的启示。文中首先介绍了美国推动节能工作的主要机构,然后从最低能耗标准、能效标识、节能工作参与群体的市场定位、基于市场的节能激励机制及政府机构节能等方面详细阐述了美国节能政策制定和实施的基本特点,并结合我国的国情分析了美国节能管理模式对我国节能工作的启示,最后提出了相关政策建议。  相似文献   
6.
A 1-D transient model (RESHEAT), developed by the writers, was used to study the thermal performance of a highly reflective paint applied sequentially to the outer walls and roof of a simulated residence in a hot and arid region of the southwestern United States. The model uses climatological inputs from a file that includes hourly data on ambient temperatures, insolation, cloud cover, and so on, at the particular location. The model focuses particularly on the potential cooling load reduction due to the reduced heat pickup from the inside attic surfaces to the outer surfaces of the supply duct. This simulation showed that a reduction of 33.6% (cooling load) on the average is achieved over the base case where no reflective paint is used when the outer surface of the roof and walls are painted. Alternatively, only a 11% reduction would be achieved if the reflective paint is applied only to the roof. Savings of $42 per month are conservatively estimated from calculations made when applying this technology to a typical residence (roof and walls) equipped with a 4 ton refrigeration unit in the Southwest.  相似文献   
7.
The cumulative survival of Japanese hemodialysis patients is more than 2.5 times better than that of dialysis patients in the United States (U.S.). The difference is particularly pronounced in older patients, being 4 times better in patients over the age of 50 years. The mortality in U.S. patients has increased from 10 to 25% over the last three decades, but has remained stable at around 10% in Japan.
There is no obvious difference in patient selection. The Japanese accept almost as high a proportion of diabetic patients as does the United States, and the mean age of incident patients is higher in Japan.
Renal transplantation, virtually absent in Japan, should increase mortality in U.S. dialysis patients by removing patients with the highest probability of survival, but even if one adds surviving transplant patients and studies prevalent populations, the survival rate is much better in Japan. Genetic factors are unlikely to explain differences in mortality, as older Americans live much longer than older Japanese.
We speculate that the difference lies in the practice of dialysis. Patients in the United States are generally treated by much faster and shorter dialysis than in Japan. This puts a severe burden on the cardiovascular system of older patients, leading to the poorer survival rate. Japanese physicians also appear to be better trained in dialysis and to spend more time with their patients. The nursing shortage in the United States may also contribute to the increased mortality. Whatever the explanations, the U.S. dialysis community must work to equal and, hopefully, surpass the now superior survival of Japanese dialysis patients.  相似文献   
8.
This paper describes the design and application of the Atmospheric Evaluation and Research Integrated model for Spain (AERIS). Currently, AERIS can provide concentration profiles of NO2, O3, SO2, NH3, PM, as a response to emission variations of relevant sectors in Spain. Results are calculated using transfer matrices based on an air quality modelling system (AQMS) composed by the WRF (meteorology), SMOKE (emissions) and CMAQ (atmospheric-chemical processes) models. The AERIS outputs were statistically tested against the conventional AQMS and observations, revealing a good agreement in both cases. At the moment, integrated assessment in AERIS focuses only on the link between emissions and concentrations. The quantification of deposition, impacts (health, ecosystems) and costs will be introduced in the future. In conclusion, the main asset of AERIS is its accuracy in predicting air quality outcomes for different scenarios through a simple yet robust modelling framework, avoiding complex programming and long computing times.  相似文献   
9.
为不断提升高校统战对象马克思主义信仰教育与思想政治教育工作水平与效果,对部分高校统战对象马克思主义信仰教育情况进行了调查,分析了当前高校统战对象马克思主义信仰教育存在的问题,提出了相应对策.  相似文献   
10.
美国国务院和美国国务卿本是两个意译名,因其词不达意,实际上是作为两个特别的称谓来使用。多方面的复杂的原因,造成这两个中文称谓存在诸多问题。主要问题有:两个称谓别出心裁,将美国联邦行政部门中分别用同一个词表示的同一个概念,即其它部门的“部”和“部长”,单独称为“院”和“卿”,变成了不同的概念,有违原意;两个称谓中的“国务”一词,名不副实,以偏概全;两个称谓极易误导,一个将美国的内阁部门误为其国家最高行政机关,一个将美国的内阁部长误为其政府首脑;关国国务卿这个称谓还存在不伦不类的问题。这两个中文称谓总是与历史发展不相适应,不能再继续使用了。  相似文献   
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