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851.
PPE标准化技术委员会标准全程控制系统是基于互联网的PPE信息管理系统平台。该系统采用便捷的B/S架构,利用先进的计算机信息技术,将标准制修订的全过程集成到一个系统中,使标准的制修订流程实现了全程自动化管理,极大地方便了标准制修订各个环节的工作,提高了PPE标准化工作的管理水平,促进了整个行业信息化的发展,确保了国家标准计划按期高水平的完成。  相似文献   
852.
Economists advocate for using the price mechanism to manage water scarcity, but complex nonlinear rate structures prevalent in markets for municipal water obscure price signals. We conduct a randomized field experiment that jointly elicits knowledge about the cost of water and examines the impact of improved information on demand by linking a survey to water billing records. Half of our sample of 30,000 single family homeowners are randomly sent an invitation to a survey that asks questions about the water bill and the costs of water-use activities (e.g. the cost of taking a shower), and subsequently provides personalized accurate information. Results show that consumers have poor information about the marginal price of water and overestimate the costs of using water. Respondents are relatively better informed about their total bill and water consumption. In aggregate, respondents increase water use in response to the survey, potentially due to learning that water is cheaper than they previously thought. Increased consumption is concentrated among low users who are more likely to over-estimate the costs of using water.  相似文献   
853.
运营期地铁隧道结构安全信息融合监控体系初探   总被引:2,自引:1,他引:1  
以隧道结构系统特性研究为基础,以从单一正向思维模式向逆向思维、系统思维、反馈思维等全方位思维模式的转变为核心,引入并讨论了基于信息融合、分析融合、诊断融合和评价融合的体系结构,探索性地研究了运营期地铁隧道结构安全信息融合监控理论和方法体系。  相似文献   
854.
基于博弈论的安全决策信息融合   总被引:5,自引:0,他引:5  
安全信息融合的研究涉及多源信息的表示、内在联系和运动规律的研究。冗余和互补的多源信息在融合系统中不可避免地存在着相互竞争和协同作用,因而多源融合系统中的信息冲突与合作的分析成为信息融合理论研究中的核心与实质问题。博弈理论对冲突和合作局势分析与研究提供了一种定量工具,其研究成果成功地解释了多局中人在“交互决策”过程如何构造博弈的“均衡点”,以及“均衡点”所具有的各种特性。笔者在研究了博弈理论的基础上,以博弈论的观点和方法解决安全信息融合系统冲突信息环境下的融合系统决策问题,并建立了相应的模型并应用了融合算法。  相似文献   
855.
科学有效地评价企业的碳信息披露质量并探寻影响碳信息披露的主要因素,有助于进一步提升企业的碳信息披露质量水平、发挥企业在我国如期实现碳达峰及碳中和进程中的积极作用。基于碳信息披露的四个维度构建制造业企业碳信息披露质量的评价体系,综合主成分分析法和熵权法测度我国制造业企业2018—2020年真实的碳信息披露质量水平及变化趋势,有效降低评价指标的维数,避免单一熵权法权重失真情况,并通过随机森林回归识别各个指标对企业碳信息披露质量的重要性。研究发现:(1)主成分和熵权法组合可有效降低信息量少的“干扰”维度对企业碳信息披露的影响,能客观真实地评价我国制造业企业的碳信息披露质量,从而获得比传统单独采用单一方法更有效的评价结果。(2)2018—2020年,我国制造业企业的碳信息披露质量整体呈现上升趋势且2020年的碳信息披露质量水平提升最大。(3)我国制造业企业的碳信息披露质量整体偏低,不同企业间的碳信息披露质量存在较大差异。(4)企业的研发投入、总资产、总负债等因素对企业碳信息披露质量有较大影响。  相似文献   
856.
ABSTRACT

The study found that encountering new information in an online chat rather than information that participants already knew and were familiar with was more likely to reduce support for the view that climate change is due to anthropogenic causes, even though the majority of the presented information supported anthropogenic causes. Participants reported feeling more competent and knowledgeable about the topic and felt less ostracized from others in the chat when participants were already familiar with information others discussed than when information discussed by others in the chat was new information. However, they viewed other chat members as more competent and knowledgeable when those others mentioned new information. Results are discussed within knowledge deficit model of science communication and the bias for common information.  相似文献   
857.
Emergency resources are an important basis of effective emergency response. But there are many disadvantages of the Chinese traditional material reserve method in which the resources are separately reserved in different regions and sections according to the kinds of disasters. So there comes the Multi-formal and Information-based Emergency Resource Reserve System (MIERRS) in China. The reserve body and method change from the single into the multiple forms, that is, the main reserve body changes from the single government agency into the organizations combining with the military, enterprise and society, and the reserve method changes from single material reserve into the reserve combining with market reserve, talents and technology reserve, and production capacity reserve. The content of the reserve change from material to information means to develop the Emergency Resource Management Information System realizing real-time control of resource characteristics and relevant reserve information. The MIERRS leads to a reserve system with rapid response and flexible schedule. It provides a convenient platform for resource sharing, thus avoiding duplication and waste, improving the utilization of resources, reducing the reserve loss and optimizing the structure of resource reserve.  相似文献   
858.
Meierdiercks, Katherine L., James A. Smith, Mary Lynn Baeck, and Andrew J. Miller, 2010. Heterogeneity of Hydrologic Response in Urban Watersheds. Journal of the American Water Resources Association (JAWRA) 46(6):1221–1237. DOI: 10.1111/j.1752-1688.2010.00487.x Abstract: The changing patterns of streamflow associated with urbanization are examined through analyses of discharge and rainfall records for the study watersheds of the Baltimore Ecosystem Study (BES). Analyses utilize a decade (1999-2008) of observations from a dense U.S. Geological Survey stream gaging network and Hydro-NEXRAD radar rainfall fields. The principal study watershed of the BES is Gwynns Falls (171 km2). Focus is given to two Gwynns Falls basins with contrasting patterns and histories of development, Dead Run and Upper Gwynns Falls. The sharp contrasts in streamflow properties between the basins reflect the differences in urban development prior to implementation of stormwater management regulations (much of Dead Run) and development for which stormwater management is an integral part of the hydrologic system (Upper Gwynns Falls). The mean annual runoff in Dead Run (558 mm) is 35% larger than that of Upper Gwynns Falls; larger contrasts in runoff properties typify the “warm season” and are linked to storm event hydrologic response. Spatial heterogeneities in storm event response are reflected in seasonal and diurnal properties of streamflow. Analyses of storm event response are presented for June 2006, during which monthly rainfall over the BES region ranged from less than 150 to more than 500 mm. Baisman Run, the BES forest reference watershed, and Moores Run, a highly urbanized watershed in Baltimore City, provide “end-member” representations of urban impacts on streamflow.  相似文献   
859.
As the world pays more attention to low-earbon and sustainable development,there’s a growing trend in architecture,engineering and construction fields to construct greener,more energy efficient and more sustainable buildings with the help of building information modeling(BIM).As BIM application becomes popular in industry,more and more scholars and engineers point out that an integrated construction environment is better for BIM’s fully functional capability.This paper illustrates the relationship between BIM application and an integrated construction environment based on case survey data.It is found that even though an integration construction environment is not necessary in BIM application,the statistical results showed that DBB(design-bid-build)and CM(construction management)modes have great differences in BIM’s application implementation scope and implementation deepness,while DB and CM modes do not.  相似文献   
860.
Abstract

Regional vegetation pattern dynamics has a great impact on ecosystem and climate change. Remote sensing data and geographical information system (GIS) analysis were widely used in the detection of vegetation pattern dynamics. In this study, the Yellow River Delta was selected as the study area. By using 1986, 1993, 1996, 1999 and 2005 remote sensing data as basic information resource, with the support of GIS, a wetland vegetation spatial information dataset was built up. Through selecting the land-scape metrics such as class area (CA), class percent of landscape (PL), number of patch (NP), largest patch index (LPI) and mean patch size (MPS) etc., the dynamics of vegetation pattern was analyzed. The result showed that the change of vegetation pattern is significant from 1986 to 2005. From 1986–1999, the area of the vegetation, the percent of vegetation, LPI and MPS decreased, the NP increased, the vegetation pattern tends to be fragmental. The decrease in vegetation area may well be explained by the fact of the nature environment evolution (Climate change and decrease in Yellow River runoff) and the increase in the population in the Yellow River Delta. However, from 1999–2005, the area of the vegetation, the percent of vegetation, LPI and MPS increased, while the NP decreased. This trend of restoration may be due to the implementation of water resources regulation for the Yellow River Delta since 1999.  相似文献   
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