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991.
注水井组对比测试在注水方案调整中的应用   总被引:1,自引:0,他引:1  
闫长辉  陈青 《钻采工艺》2008,31(2):71-73
双河油田V上油组进入特高含水开发后期,油层水淹十分严重,必须提高注水效率,重要的基础工作就是必须准确评价注水效果。根据注水井组对比测试评价注水效果,分析注采井对应关系。通过对V上油组7个注水井组对比测试结果分析,认为V上油组注水主要有能量存在亏空和注水见效不均匀两种情况,在下一步注水方案调整中采取相应的措施:V上油组V1,V8,V9,V10小层的注水强度应有所增加,V6小层向下调整,对于渗流能力较差的小层应采取酸化工艺。  相似文献   
992.
对管线进行完整性维护是目前管道公司的一项重要任务。文章分析了油气管线风险评价技术的现状,指出目前研究工作的范围和重点;介绍了一种处理管线维护资源最优分配的技术——基于风险的管线完整性维护决策优化技术。该方法分为系统排序和决策分析两过程:系统排序按照完整性维修等级或单位风险降低费用对不同管段进行排序;决策分析评估可供选择的维修方式,确定每一个目标管段的最优维修方式。建立了管道完整性维护决策的数学模型,模型包括五要素:状态集、决策集、概率分布、后果函数、决策准则与最优值。着重介绍了完整性维护决策优化的效用函数方法,包括效用函数的定义、分析原理、多准则效用函数的评估方法、基于效用函数的决策树、效用函数的构成等。还介绍了有限费用的决策优化方法。最后指出定量风险评价以及该技术中存在的难点,并提出建议。  相似文献   
993.
模糊评价系统中隶属函数构造与修正   总被引:3,自引:0,他引:3  
本文系统地提出了在模糊评价中构造隶属函数时,应根据各评价因素的特征,选择不同的构造方法,本文采用了统计类比法、待定系数法和多元隶属函数法三种不同方法来构造隶属函数,同时提出了隶属函数修正及其神经网络自学习模型,并将上述思想成功地运用到了具体的评价系统中。  相似文献   
994.
The effect of three different functional groups in ethylene copolymers on the adhesion with aluminium was studied. The interface in polymer/metal laminates was analyzed by FT-IR, and the adhesion mechanism for each functional group was evaluated. Laminate samples were prepared by solution casting or by hotpressing polymeric film onto the aluminium substrate. In the latter case, the interface was exposed by solvent extraction. The interfacial structures developed by the different copolymers were correlated to the mechanical strength of hotpressed laminates, which was measured by a peel test. The polymer surfaces were further characterized by contact angle measurements.

Polar functional groups, carboxylic acid and butyl ester in hotpressed laminates were found to form Lewis acid/base interactions with the aluminium oxide. The strength of the interfacial interactions was correlated to the concentration and acidity/basicity of the group, the acid group being the most efficient. A silane functional group provided strong adhesion to the laminates at a much lower concentration than the polar groups. Silanols as well as Al-O-Si linkages were detected at the polymer/aluminium interface.  相似文献   
995.
We tested the claim that computer-mediated communication (CMC) is more egalitarian than face-to-face (FTF) communication by studying patterns of reported participation and influence in 30 FTF and 30 synchronous CMC groups over seven weeks. Twenty-two of these groups were composed of a majority of males or females; these were used to test effects of communication medium and sex composition on relative levels of participation and influence among group members. Competing predictions were derived from three theories: proportional theory, social role theory, and expectation states theory. Results indicated that CMC participation was perceived as more centralized than was FTF participation in groups' first meetings, but as similar for the remaining six meetings. Results revealed no or weak support for any of the competing theories of sex composition. Influence was perceived as most centralized in CMC majority-male groups and in FTF majority-female groups. In CMC groups, males in majority-female groups were perceived as having more influence than their female group members, whereas males in majority-male groups were perceived as having less influence than their female group members. In FTF groups, the ratio of male-to-female influence in majority-male and majority-female groups did not differ significantly. Implications of these findings and the need for additional longitudinal research are discussed.  相似文献   
996.
Reviews the book, Assessing and treating culturally diverse clients: A practical guide by Freddy A. Panaigua (see record 1996-97152-000). This book is a timely and provocative delineation of highly relevant considerations to be made by counselors, psychotherapists, and other mental health professionals in the delivery of services to multicultural groups. The book deals with four ethnic populations in the United States—African American, Hispanic, Asian, and American Indian. Panaigua's contribution is part of a series on Multicultural Aspects of Counseling by Sage Publications. The purpose of the series is to increase the mental health practitioner's knowledge and sensitivity to cultural differences and to assist in alleviating bias in the therapeutic process. This purpose is accomplished with precision and insight by Panaigua. Unlike some other books dealing with cultural diversity, Panaigua's work offers specific treatment methods which have been demonstrated to be successful in treating members of the targeted groups. Problem solving and social skills training are recommended in some cases. In other instances, assertiveness training, music therapy, or direct advice are the modalities of choice. In other cases, education, medication, or behavioral approaches are preferred. Assessing and Treating Culturally Diverse Clients can serve the educational needs of graduate students in the fields of psychology, counseling, family therapy, and social work. It is an excellent guide for use in either the training or practice of these helping professions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
在城市人防工程可行性研究中,目前应用的方法很多。本文利用模糊数学综合评判的理论,提出了一个评判人防工程开发项目的方法,并能处理一些含经验的问题。  相似文献   
998.
An experimental study of 60 work groups that met weekly either face to face or via a computer conferencing system for seven weeks is described. The experimental design, computer technology, experimental tasks, and composition of the groups are described in detail. A brief overview is given of the five empirical pieces in this special issue that report findings from this experimental study.  相似文献   
999.
Information Analysts must be able to gather information and interpret it reliably to promote good organizational decision making. The Information Analyst has three ways of obtaining this information: (1) interviewing, (2) investigation of hard data, and (3) observation. Until recently, observation has only been accomplished subconsciously. This paper describes how STRuctured OBservation of the Environment (STROBE) was used to aid in determining the information requirements of a regional blood service organization. STROBE was developed from a methodology used in film criticism. It is conceptualized by drawing a parallel between the concrete and abstract elements in a film, and similar elements found in an organization. It is then applied to the blood service organization and examples are provided for both concrete and abstract elements. These examples demonstrate that structured observation provides information unobtainable through interviewing and investigation.  相似文献   
1000.
本文通过对沈抚灌区土壤及水稻的采样分析,同时结合水稻盆栽试验,分析测定了污灌区土壤中石油烃的残留及其对水稻生长的影响。结果表明土壤中石油烃含量同污灌年限、物理性粘粒含量及土壤质地等有着一定的相关关系,土壤中石油烃含量越高对水稻生长发育的影响越大。  相似文献   
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