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1.
用于钻水平井的低密度水包油乳化钻井液 总被引:4,自引:0,他引:4
针对任平1井水平钻井的特点,研制了一种低密度、高油水比的水包油乳化钻井液。考察了乳化剂、增粘剂和配制工艺对乳状液性能的影响,评定了钻井液性能,介绍了现场应用情况。该钻井液性能稳定,润滑性好,净化井眼的能力强,能满足水平段钻井的要求。 相似文献
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Blanchard Kimberly A.; Morgenstern Jon; Morgan Thomas J.; Lobouvie Erich W.; Bux Donald A. 《Canadian Metallurgical Quarterly》2003,17(4):328
Negative consequences are an important component of the substance use change process, yet no standardized measure exists to assess consequences of use. This study evaluated the psychometric properties of the Inventory of Drug Use Consequences, a self-report measure assessing drinking and drug use consequences. Participants (N=252) were assessed at entry into outpatient substance abuse treatment. Items loaded strongly on 1 factor, and internal consistency of the total scale was high. Fifteen items with the highest correlations with the total scale were chosen to represent the construct. The shortened measure exhibited good internal consistency, convergent and discriminant validity, and detected change over time and may be the measure of substance use consequences that is lacking in the field. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Investigating the Impact of Familiarity and Product Conditions on The Ease of Use of a Product 下载免费PDF全文
Aththanayake Chandima Gayan PERERA 《国外电子测量技术》2021,8(2):40-48
Ease of use is one of the main criteria that customers consider when making a purchase decision. To provide a pleasant experience to the customers, offering products or services consisting of advanced features and functions is no longer enough, due to the existing competition in the global market. In reality, the ease of use of any product is influenced by the conditions of the product and the familiarity of the user. This study examines the influence of the familiarity and the product conditions on the ease of use of a product. This only explains how the conditions of the product and the fa-miliarity of the user, influence on the ease of use of a product when the usage hours of a product increases. A case study would be conducted to validate the results. The results of this study indicate that in the case where both the product conditions and the familiarity has been varied, the ease of use of the product has been increased from 0.229 to 0.380 gradually within the 10 weeks period. Through these results valuable guidance could be obtained by the manufacturers to identify how the ease of use level of a product deviates from the standard level when the usage hours of the product would increase. 相似文献
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The availability of a system or equipment is one of the crucial characteristics that measures the customer satisfaction and strongly influences his final choice decision between concurrent products. The aim of this work is to provide an approach to improve the products availability assessment by taking into account the safety criteria by considering the use situations at design stage. Our work focuses on the routine design of complex products. The availability is often simply estimated considering reliability and maintainability. Basically, the intrinsic availability is the probability that it is operating satisfactorily at any point in time when used under conditions stated by design specifications. The time considered includes operating time and active repair time. Thus, intrinsic availability excludes from consideration all other times in the product lifecycle such as: accident management time, storage time, administrative time or logistic time. But many studies show that the loss of availability performance is also due to accidents that occur in different unforeseeable utilization situations. This engenders stops of the system to ensure the users safety according to standards recommendations. In this purpose, we consider the structural product architecture and the different use cases that correspond to the operational states and downtimes due to stop events that may happen during the utilization like failures, maintenance tasks and accidents. Then, we propose a product behavioral analysis including the use cases to describe interactions between the product and users or maintenance operators. We use Markov chains to model the use cases corresponding to operating time (OT), maintenance time (MT) and preparing time after accidents (RT). Then these three parameters are considered to specify a generic approach to improve the availability assessment. Such an approach provides the traceability of the product behavior along its lifecycle. In this way, the main causes of stop can be identified and this may guide the designer for improving the availability of the product future versions. To validate our approach, an application is presented considering a printing line. The comparison of our simulation considering an industrial case study shows a good agreement about the influence of safety on the availability. 相似文献
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采用电镜分析、反相色谱、毛细管流变仪和布拉本达塑性仪研究了由锦西化工研究院生产的PVC管用树脂的颗粒形貌、比表面积、流变性能和加工速率。结果表明,该树脂和疏松型树脂的形貌呈棉桃状不同,外形为球状,比表面积较大,约比普通SG-5型树脂增加1倍,最高可达1.007m^2/g;在从低剪切到高剪切速率范围内,该树脂的表观粘度均比SG-5型树脂低,不论是采用粒料还是粉料挤出,在聚合度相同时,该树脂的挤出速率 相似文献
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古志华 《计算机光盘软件与应用》2011,(20)
本文通过探讨平面设计软件在中职艺术类院校的运用,提出了如何让学生在有限的时间里快速掌握多种平面广告设计软件的途径,对中职学生如何学好平面广告设计课程做出了一些思考。 相似文献
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廖彬 《计算机光盘软件与应用》2011,(12)
本文基于SQL Server 2000数据库,通过对索引开销的研究,针对如何建立最适当索引的问题给出索引选择模型以及相应算法,并比较各算法的优劣,确定最优选择 相似文献
10.
XIA Yan 《电脑编程技巧与维护》2008,(16)
NetBeans IDE是当前市场上最流行的、开源且免费的集成开发工具。使用NetBeans不仅可以开发Java程序,还提供了对UML的全面支持。利用NetBeans UML建模模块,可以创建八种类型的UML图,极大地方便了开发人员编写程序。本文首先介绍了NetBeans和UML的基本知识;其次着重介绍了如何在NetBeans IDE中实现UML建模;最后,通过创建一个酒店系统的用例图实例加深理解。 相似文献