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51.
The purpose of this study was to examine the relationships between computer use, identity formation, and self-esteem among Black and White emerging adult females. One hundred 56 female college students participated in this study by completing a survey that included the Internet/Computer Use Questionnaire, the Ego Identity Process Questionnaire, and the Rosenberg Self Esteem Scale. Racial differences were found between Black and White females with regard to perceived problematic use of the Internet and use of the computer for communication and use of the Internet for schoolwork. In addition, differences between Black and White females were found between identity formation and problematic use of the Internet and between self-esteem and type of use of the Internet. These findings were discussed in relation to future research and interventions.  相似文献   
52.
Abstract.  While a large body of research exists on the development and implementation of software, organizations are increasingly acquiring enterprise software packages [e.g. enterprise resource planning (ERP) systems] instead of custom developing their own software applications. To be competitive in the marketplace, software package development firms must manage the three-pronged trade-off between cost, quality and functionality. Surprisingly, prior research has made little attempt to investigate the characteristics of packaged software that influence management information system (MIS) managers' likelihood of recommending purchase. As a result, both the criteria by which MIS managers evaluate prospective packaged systems and the attributes that lead to commercially competitive ERP software products are poorly understood. This paper examines this understudied issue through a conjoint study. We focus on ERP systems, which are among the largest and most complex packaged systems that are purchased by organizations. In a conjoint study, 1008 evaluation decisions based on hypothetical ERP software package profiles were completed by managers in 126 organizations. The study represents the first empirical investigation of the relative importance that managers ascribe to various factors that are believed to be important in evaluating packaged software. The results provide important insights for both organizations that acquire such systems and those that develop them. The results show that functionality, reliability, cost, ease of use and ease of customization are judged to be important criteria, while ease of implementation and vendor reputation were not found to be significant. Functionality and reliability were found to be the most heavily weighted factors. We conclude the paper with a detailed discussion of the results and their implications for software acquisition and development practice.  相似文献   
53.
我国建筑涂料技术进步简评   总被引:1,自引:1,他引:0  
从以下诸方面简述我国建筑涂料的技术进步:⑴新品种涂料的研制开发;⑵加强对配套材料及施工技术的研究;⑶超细填料在涂料中的应用;⑷计算机自动配色技术;⑸产品标准的修订;⑹建筑涂料的实用范围扩大。  相似文献   
54.
介绍了机电一体化技术在国内外煤矿井下综采设备中的应用,并论述了机电一体化技术发展与相关技术的研究。  相似文献   
55.
随着西北勘测设计研究院(以下简称西北院)勘测总队所承担的黄河龙 ̄青段、白龙江流域等河段前期综合勘测工作的相继结束,拥有2000多名职工的勘测队伍面临着何去何从的重大选择。在此转折关头,勘测总队面对现实,审时度势,抓住机遇,开拓前进,及时转轨变型,制定了本单位发展的战略和方向,使勘测总队由单一勘测业务转变为集勘测与岩土工程施工为一身的新型综合队伍。几年来,经过全体职工的奋发努力,缍获得了1995年 ̄  相似文献   
56.
根据第十三届国际普兰西会议获得的信息,对国际上难熔金属、硬质合金、硬质材料和涂层技术等方面近几年来的研究和发展动态进行了综合评述。最后,提出了几点自己的看法。  相似文献   
57.
镍代钴矿用硬质合金的新进展   总被引:2,自引:0,他引:2  
概述了镍代钴矿用硬质合金的国内外进展情况.  相似文献   
58.
59.
The compaction properties of an investigational drug are studied by the use of a compaction simulator. The effects of punch velocity over the range of 30-640 mm-1 on the compaction properties of the pure drug and a variety of formulas incorporating a high dose of the active compound have been investigated. The data were analyzed by applying the Heckel equation. The pure drug was found to have a high yield pressure at a relatively low punch velocity of 31 mm-1. As the punch velocity was increased there was a decrease in crushing strength, primarily as a result of increasing yield pressure. These findings indicate that the pure drug predominantly consolidated by fragmentation and elastic deformation, with a slow plastically deforming component. The information obtained on the consolidation mechanism of the pure drug and, subsequently, on model formulas were instrumental in the design and selection of a robust formula and granulation process. The advantages of conducting dosage form design and characterization studies during the early phase of tablet formulation using means such as a compaction simulator are emphasized in this investigation.  相似文献   
60.
石油钻井用泥浆泵的新发展   总被引:1,自引:1,他引:0  
泥浆泵已发展到大功率、大排量、高压力。为适应现代钻井技术的发展,钻井设备制造商开发出了性能更好,体积更小,质量更轻的泥浆泵,以满足钻井承包商适应各种钻井工况的需要。文章简要介绍了近几年国内外新出现的几种泥浆泵。  相似文献   
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