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991.
近50年来长江宜昌站水温变化的多尺度分析   总被引:10,自引:0,他引:10  
基于1956~2006年月均水温和年均水温资料,采用复Morlet小波函数,对长江中游宜昌水文站近50年来河流水温的年内变化和年际变化时间序列进行了小波分析,揭示了宜昌水文站水温变化的多时间尺度的复杂结构,分析了不同时间尺度下水温序列变化的周期和突变点,并根据主周期对未来水温变化进行了预测。结果表明,近50年来宜昌站河流水温变化具有多层次的时间尺度结构,年水温和各季节水温均存在10~16年和4~6年左右时间尺度的周期变化,水温变化的阶段性特征明显。经水温变化趋势分析,2006~2008年左右年均水温处于偏高期,在2009~2012年左右水温将偏低。该研究结果为长江中游宜昌江段重要水生生物动态变化的水温响应研究提供了参考。  相似文献   
992.
通过结合南京地铁3号线新庄站的地质条件与设计方案分析,认为钻孔咬合桩作为围护结构是可行的,同时针对钻孔咬合桩的超缓凝混凝土初凝时间、施工垂直度及成桩过程中存在问题的工程措施展开了研究。  相似文献   
993.
In this paper, to analyze the discontinuity structure of E-plane metal insert by mode matching method, and metal insert thickness and resonator length impact on filter design. This work was supported by the Natural Science Foundation of Jiangsu Province of China under Grant No. BK2008357.  相似文献   
994.
Currently, infection control guidelines in hospitals and other health care institutions are more expert-driven than user-oriented. In order to enhance the usability of the expert-driven guideline format, we developed a website for the communication of existing guidelines that better fit the practical information needs of health care workers (HCWs). We employed a user-centered design process that involved two studies.In the initial study, 28 HCWs were asked to solve tasks using existing, paper-based infection control guidelines. In order to detect their strategies and problems, the participants were asked to think aloud. Usability problems occurred due to poorly structured information, insufficient quality of information, and a mismatch between experts’ and HCWs’ vocabulary. To overcome these shortcomings, three design principles were applied for communicating infection control guidelines: better navigation (the guidelines should be searchable in several ways); multimodality (the guidelines should not be presented as text only), and action-orientation (the guidelines should be presented as HCWs’ behaviors). A website was developed to meet these principles.In the second study, the same 28 HCWs completed tasks identical to those of the first study while thinking aloud, but this time using the website. The percentage of correctly completed tasks increased and the mean time for task completion decreased significantly. Also, respondents were more satisfied with the website than the paper-based guidelines. The number of problems due to poor information quality and a mismatch in vocabulary declined, although the number of structural problems increased. This can probably be explained by the fact that the navigation structure was user-generated (using Card Sort), in contrast to a standardized answer format based on common usability principles.Overall, we found that involving HCWs in the development process is important to create a sense of ownership and to foster the implementation of the guidelines, which might eventually result in compliance and reduce health care-associated infections. This paper outlines concrete steps for how to involve HCWs in the design process.  相似文献   
995.
刘敏慧 《电子测试》2013,(9X):122-123
进入信息时代后,面对不断加深的金融改革以及瞬息万变的金融市场,地方中小商业银行开始需要应对住诸多的不利因素。战略联盟逐渐成为中小商业银行扩大生存空间、谋求自身发展的重要经营战略选择。本文通过对信息时代中小商业银行战略联盟现状的分析,指出了其存在的不足和问题,并提出了信息时代下加强战略联盟稳定性的相关建议。  相似文献   
996.
The configuration and mechanical behavior of steel-concrete composite cable-pylon anchorage in cable-stayed bridges are very complex. Considerable local deformation of composite cable-pylon anchorage zone could occur under the horizontal component of the inclined cable force. It is difficult and unfeasible to analyze the horizontal mechanical behavior of the composite cable-pylon anchorage by the traditional analytical theory of composite structures. In this paper, full-scale model tests were carried out according to an actual project to analyze the horizontal mechanical behavior of composite cable-pylon anchorage. Stress distribution patterns of the main members and the failure modes were obtained. Structural response of the anchorage was analyzed by spatial solid and shell finite element model. By analyzing and simplifying the configuration and details of the structure, the expression for calculating the horizontal force burdened by the main members of composite cable-pylon was derived based on the deformation compatibility principle. The equation for calculating internal forces of the main members in the composite cable-pylon anchorage was also obtained. It is shown that the proposed simplified method agree well with the experimental result and finite element method result.  相似文献   
997.

Arch dam deformation is comprehensively affected by water pressure, temperature, dam’s structural behavior and material properties as well as other factors. Among them the water pressure and temperature are external factors (source factors) that cause dam deformation, and dam’s structural behavior and material properties are the internal factors of deformation (resistance factors). The dam deformation is the result of the mutual game playing between source factors and resistance factors. Therefore, resistance factors of structure and materials that reflect resistance character of arch dam structure are introduced into the traditional model, where structure factor is embodied by the flexibility coefficient of dam body and the maximum dam height, and material property is embodied by the elastic modulus of dam. On the basis of analyzing the correlation between dam deformation and resistance factors, the game model of safety monitoring for arch dam deformation is put forward.

  相似文献   
998.
信息传播贯穿社会风险扩散的全过程,政府治理行为对风险信息传播有着重要影响,直接影响社会风险治理效果。本文在分析信息传播与社会风险关系的基础上,阐述信息治理的必要性,结合政府在信息治理中的主体地位,借鉴经典传染性模型,构建社会风险信息传播模型,研究政府治理行为对其传播规律的影响,并以工程项目社会风险治理为例进行仿真研究。仿真结果表明:1)政府信息治理延长了风险信息传播达到峰值和稳态的时间,有助于减缓社会风险传播;2)行政干预与正面回应都能增加信息传播系统中易感者比例,减少感染者比例以及达到峰值时的潜伏者比例,同时达到减缓社会风险信息传播的目的;3)正面回应对信息传播系统中各参数影响较大,正面回应手段更有效。从信息搜集、处理、发布的信息流动全过程视角,提出相关政策建议。  相似文献   
999.
Gravity dam is a typical structure that has been frequently used in the fields of water conservancy engineering, and the safety of the structure has received widespread attention recently. Due to earthquakes or other reasons, gravity dams normally have damage such as cracks in practical service. Damage in the structures can alter the structural dynamic behavior and seriously affect structural performance. Maintaining safety and integrity of the gravity dam structures requires a better understanding of dynam...  相似文献   
1000.
In order to utilize water and hydropower resources in China,multitudes of water projects are established or to be constructed as an integral part of the national economy's infrastructure.Under these circumstances,there are two outstanding problems:1) a mass of existing dams are in danger and 2) in the southwest water-conservancy construction plan,dozens of existing or planned dams are high dams or even super high dams with heights between 200 and 300 m.In accordance with demands of the National Program for ...  相似文献   
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