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近海大体积混凝土结构所处的外界环境以及地质条件比较复杂,对于带裂缝水闸结构来说,因所处的地理位置、气候变化以及潮汐升降水位等因素的缘故,水闸闸墩裂缝处于张合状态,这降低了水闸结构的稳定性,甚至会影响水闸结构的寿命。沿海环境温度变化对混凝土裂缝宽度变化的实际监测分析,对于混凝土结构安全耐久性评价具有一定价值,依托典型软土地基永定新河防潮闸工程,利用测缝计对闸墩裂缝宽度变化进行健康监测。主要研究运行期环境因素(以空气温度、水温以及潮汐水位为主)对闸墩裂缝的影响,采用健康安全监测软件,通过对数据的挖掘处理,得出环境温度和水位是影响闸墩水下裂缝宽度变化的敏感性因素的结论,为以后水闸闸墩裂缝的安全维护和裂缝的预防提供思路。 相似文献
125.
The nanometer scale topography of self‐assembling structural protein complexes in animals is believed to induce favorable cell responses. An important example of such nanostructured biological complexes is fibrillar collagen that possesses a cross‐striation structure with a periodicity of 69 nm and a peak‐to‐valley distance of 4–6 nm. Bovine collagen type I was assembled into fibrillar structures in vitro and sedimented onto solid supports. Their structural motif was transferred into a nickel replica by physical vapor deposition of a small‐grained metal layer followed by galvanic plating. The resulting inverted nickel structure was found to faithfully present most of the micrometer and nanometer scale topography of the biological original. This nickel replica was used as a die for the injection molding of a range of different thermoplastic polymers. Total injection molding cycle times were in the range of 30–45 seconds. One of the polymer materials investigated, polyethylene, displayed poor replication of the biological nanotopographical motif. However, the majority of the polymers showed very high replication fidelity as witnessed by their ability to replicate the cross‐striation features of less than 5 nm height difference. The latter group of materials includes poly(propylene), poly(methyl methacrylate), poly(L ‐lactic acid), polycaprolactone, and a copolymer of cyclic and linear olefins (COC). This work suggests that the current limiting factor for the injection molding of nanometer scale topography in thermoplastic polymers lies with the grain size of the initial metal coating of the mold rather than the polymers themselves.
126.
能源多元化对保障国家能源安全,紧跟世界能源发展趋势,及时转变能源发展战略的意义重大。分类讨论替代燃料,分析其发展态势和需要的支撑条件。 相似文献
128.
Various human factors classification frameworks have been used to identified causal factors for clinical adverse events. A systematic review was conducted to identify human factors classification frameworks that identified the causal factors (including human error) of adverse events in a hospital setting. Six electronic databases were searched, identifying 1997 articles and 38 of these met inclusion criteria. Most studies included causal contributing factors as well as error and error type, but the nature of coding varied considerably between studies. The ability of human factors classification frameworks to provide information on specific causal factors for an adverse event enables the focus of preventive attention on areas where improvements are most needed. This review highlighted some areas needing considerable improvement in order to meet this need, including better definition of terms, more emphasis on assessing reliability of coding and greater sophistication in analysis of results of the classification.
Practitioner Summary: Human factors classification frameworks can be used to identify causal factors of clinical adverse events. However, this review suggests that existing frameworks are diverse, limited in their identification of the context of human error and have poor reliability when used by different individuals. 相似文献
129.
《Information and Software Technology》2014,56(5):506-515
ContextWhile project management success factors have long been established via the golden triangle, little is known about how project iteration objectives and critical decisions relate to these success factors. It seems logical that teams’ iteration objectives would reflect project management success factors, but this may not always be the case. If not, how are teams’ objectives for iterations differing from the golden triangle of project management success factors?ObjectiveThis study identifies iteration objectives and the critical decisions that relate to the golden triangle of project management success factors in agile software development teams working in two-week iterations.MethodThe author conducted semi-structured interviews with members across three different agile software development teams using a hybrid of XP and Scrum agile methodologies. Iteration Planning and Retrospective meetings were also observed. Interview data was transcribed, coded and reviewed by the researcher and two independently trained research assistants. Data analysis involved organizing the data to identify iteration objectives and critical decisions to identify whether they relate to project management success factors.ResultsAgile teams discussed four categories of iteration objectives: Functionality, Schedule, Quality and Team Satisfaction. Two of these objectives map directly to two aspects of the golden triangle: schedule and quality. The agile teams’ critical decisions were also examined to understand the types of decisions the teams would have made differently to ensure success, which resulted in four categories of such decisions: Quality, Dividing Work, Iteration Amendments and Team Satisfaction.ConclusionThis research has contributed to the software development and project management literature by examining iteration objectives on agile teams and how they relate to the golden triangle of project management success factors to see whether these teams incorporate the golden triangle factors in their objectives and whether they include additional objectives in their iterations. What’s more, this research identified four critical decisions related to the golden triangle. These findings provide important insight to the continuing effort to better assess project management success, particularly for agile teams. 相似文献
130.
《Expert systems with applications》2014,41(1):69-80
This paper attempts to study the impact of customer satisfaction and the Chinese electronic retailers (E-retailers) competitiveness using quality factors. Two conceptual models based on asset-process-performance (APP) competitive theoretical framework have been proposed. The proposed models include E-retailers strategic factors such as logistics, quality and customer satisfaction equivalent to asset, process and performance entities of the APP framework. Using an empirical survey from a young population, this study, with the support of structural equation modeling (SEM) identifies reliability in service quality and purchasing experience in e-service quality as dominant customer satisfaction factors. This study uses both exploratory and confirmatory factor analysis and suggests that to be competitive Chinese E-retailers have to focus more on the delivery of products (logistics) compared to other intangible service quality factors. On theoretical front, this study is a novel attempt to validate the APP framework for E-retailers’ competitiveness. On the practical front, the outcome of the study would be highly beneficial to the Chinese E-retailers to fine tune their strategy to satisfy the growing demand. Furthermore, this study can supplement government policy makers to regulate the growing volatile market. 相似文献