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91.
不同形貌氢氧化镁的化学合成及影响因素   总被引:2,自引:0,他引:2  
对不同形貌氢氧化镁的化学合成及外部生长环境进行了综述。尤其对影响氢氧化镁结晶性能和形貌起关键作用的因素,如碱性沉淀剂的选择、合成温度的确定、不同镁盐的影响、碱和镁盐的初始浓度及配比、水热处理、反应物的混合方式、晶形控制剂的加入等,进行了详细的阐述。  相似文献   
92.
介绍了隔膜碱整流装置发生的整流器故障的经过,并对事故进行了分析,进而提出了类似事故的预防措施。  相似文献   
93.
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   
94.
95.
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   

96.
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   
97.
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   
98.
油滴釉制作工艺的研究   总被引:2,自引:0,他引:2  
在研制氧化气氛烧制油滴黑釉器的基础上 ,探讨了影响油滴釉形成的工艺因素。通过一系列试验 ,进一步验证了油滴釉在结晶过程中主要发生了液液分相 ;釉料的化学组成是油滴晶斑形成的先决条件 ;釉层厚度、烧成制度等是决定釉面效果的重要因素 ;油滴晶斑的呈色不仅与烧成气氛有关 ,还与着色氧化物的引入有关。  相似文献   
99.
During early design and development stages, every engineering system has to meet its specific reliability goals. The target reliability of the system is achieved through application of an effective reliability apportionment technique to its subsystems. There are various traditional methods exist to perform the reliability allocation based on engineering factors that are assessed in a subjective manner. The conventional reliability allocation approach requires the assessment of factors like complexity, cost, and maintenance. This may not be realistic in real applications if they are assessed in a crisp manner by the domain experts of their varied expertise and background.In this paper, we treat allocation factors as fuzzy numbers, which are evaluated in fuzzy linguistic terms. As a result, fuzzy proportionality factor scales are proposed for the subsystems. In order to accomplish fuzzy division to evaluate the fuzzy proportionality factor, an approximation method based on linear programming for trapezoidal fuzzy numbers is also proposed in this paper. For the evaluation of weighting factors from fuzzy proportionality factors, centroid method of defuzzification is being employed. The allocated reliability of each subsystem is computed with the help of weighting factor thereafter. An example is provided to illustrate the potential application of the proposed fuzzy based reliability allocation approach.  相似文献   
100.
催化热裂解工艺机遇及影响因素   总被引:2,自引:0,他引:2  
分析了催化热裂解过程的反应机理及乙烯和丙烯形成的反应,乙烯和丙均可通过热裂解和催化裂解生成,讨论了影响乙烯,丙烯产率的因素:与USY和REY相比,使用ZSM-5催化剂能够提高乙烯,丙烯产率,磷改性ZRP-1经碱土金属改性后,可进一步提高乙烯和丙烯的产率,提高反应温度和降低剂油比,能够提高热裂解和催化裂解的比例,有利于乙烯产率的提高;增强蒸汽量能够减少焦炭产率,提高乙烯和丙烯产率。  相似文献   
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