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61.
The world is facing a global water crisis. Already, deficiencies in water supply and water quality are causing widespread human suffering. About 1.1 billion people lack access to clean water, and 2.6 billion do not have access to improved sanitation facilities. Everyday, 4500 children throughout the world die from preventable diseases caused by the lack of clean water and sanitation. China, India, and the United States are all facing major shortages of freshwater, and water pollution is having serious impacts on public health and the environment in both China and India. Major investments in science and technology will be required to address the water issues of the future. A new generation of innovative, small-scale technologies is needed to prevent and control pollution, and to restore watersheds. Creative, collaborative approaches to addressing the world's decline in freshwater resources are urgently needed. 相似文献
62.
徐斐达 《特种铸造及有色合金》2011,31(11):1032-1035
面对现阶段愈演愈烈的用工荒,从宏观与微观两方面分析了用工荒产生的成因、特点、分布,利用人力资源管理理论,阐述了一些企业用工方面存在的典型问题以及用工误区,提出了一些建设性的意见与措施。 相似文献
63.
The Building Research Institute in Warsaw has developed an organic concrete additive, known as Dikszopt, which is derived from tanning oak extract. Tests, mostly in the laboratory but some in application trials, show that it has a remarkable ability to protect reinforcing steel against corrosion, notably in carbonized concrete. It also appears to improve the consistency of the concrete mix and retard the setting time, as discussed in this article from the Institute. 相似文献
64.
G. Tomei D. Cerratti E. Tomao D. Vacca M. Di Famiani S. De Sio 《The Science of the total environment》2010,408(4):681-508
The aim of our meta-analysis is to evaluate the association between the modifications of the cardiovascular system and chronic exposure to noise in occupationally exposed subjects.We considered the articles published from 1950 to May 2008. Only 15 papers were conforming to the inclusion criteria identified for this meta-analysis. A total of 18,658 workers were divided in three groups according to the level of noise exposure as measured in the original studies (High Exposure, HE, Intermediate Exposure, IE, Low Exposure, LE). A preliminary evaluation of the type of data allowed for a classification of the type of performed measurements. Two classes of variables were identified: Class I, composed by continuous variables (systolic blood pressure, SBP, diastolic blood pressure, DBP, and heart rate, HR) and Class II, composed by not continuous variables (prevalence of hypertension and prevalence of ECG abnormalities). For each variable the calculation of heterogeneity was performed. For continuous variables the calculation of ES and its significance were performed while Odds Ratio (OR) and its significance were calculated for not continuous variables.The results show a statistically significant increase of SBP and DBP in HE workers compared to LE and IE workers while HR is statistically higher in HE participants compared to LE participants. The prevalence of both hypertension and ECG abnormalities is statistically higher in HE workers compared to LE and IE workers.Taking into account both the extremely high heterogeneity among studies and the ES/OR values we suggest a particular attention to the measurement and evaluation of SBP, DBP and HR in workers with chronic exposure to noise. Also ECG for workers with chronic exposure to noise is suggested in order to identify and evaluate possible abnormalities noise could be a concurrent cause of. 相似文献
65.
物联网是当前信息领域中研究的热点。本文以CC1110芯片为核心,利用温湿度、烟雾、亮度等传感器结合自主开发的WIA-PA协议栈软件,研制了一种基于433MHz频段的物联网开发平台。利用该平台提供的开发套件,可方便地开发智能家居、环境监测等应用系统。目前,重庆伟岸测器利用本平台已成功开发了无线热能表系统。 相似文献
66.
Ron Craig 《Construction Management & Economics》2013,31(1):91-100
The UK's NJCC Code of Procedure for Single Stage Selective Tendering (now withdrawn) and its successor, the CIB's Code of Practice for the Selection of Main Contractors are criticized in the light of decisions of the common law courts with regard to regulation of the tendering process. It is argued that a new ‘Tendering Code’ should be produced in the style and format of a contract document which reflects not only the statutory regulation imposed on public bodies, but common law decisions of the courts. The nature of this tendering contract is explained as a means of regulating the tendering process. Issues discussed are: dealing with errors and irregularities found in tenders; dealing with non-compliant tenders; dealing with tender withdrawal prior to its acceptance or rejection; making provisions as to time for submission of tenders and dealing with late tenders; making provision for submission of tender by fax or other electronic means; making provision for evaluation of tenders received; and imposing or negotiating reductions in price with tenderers prior to acceptance. The paper concludes that the common law obligations placed on the owner to treat all tenderers equally and fairly and to apply the tender conditions when evaluating tenders and awarding contracts seems to be good common sense and of commercial advantage, not only to the immediate parties concerned but also to the wider community. 相似文献
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