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The United Parcel Service (UPS)–Motorola case study revolves around two major areas of information technology (IT) management: IT as a competitive tool and global outsourcing of IT projects. It provides an opportunity to become familiar with the decisions and actions taken by UPS to assure their competitive advantage in the turbulent courier services industry. In the IT outsourcing area, the case addresses managerial and technical issues associated with outsourcing IT projects across the global community. The case presents the specific factors that made this outsourcing project successful and discusses the development of the outsourcing relationships between UPS and Motorola (Israel), from initial negotiations to the creation of a strategic alliance between the two companies. A major point in this case is the gradual development of trust between the two sides, trust that led the two firms from being committed to a contract to becoming strategic partners.  相似文献   
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This paper deals with the interpretation and feasibility check of line drawings representing polyhedral scenes. The polyhedra are of general types and there are no restrictions on camera position. The geometric consistency check and the line labeling are carried out through constructions in the image plane. An algorithm for the geometric construction is suggested, and the necessary conditions for these constructions are discussed. The image plane construction can be used for preparing labeled junction catalogs for junctions other than trihedral. In addition the paper analyzes the relation between the image plane construction and the gradient space construction suggested by Mackworth [7] for the same purpose.  相似文献   
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微波辅助polyol法制备纳米金属镍及磁性研究   总被引:1,自引:1,他引:0  
采用微波辅助polyol法成功地制备了直径范围在5~10nm、100~180nm的单分散Ni球,对其磁性进行了测量分析.用XRD和EDAX,接着用TEM和MFM分别对制备的样品进行测试,并用VSM和SQUID进一步讨论了铁磁/反铁磁的界面耦合效应.XRD显示该样品是面心立方结构,EDAX数据表明制备过程中镍球被轻微氧化,MFM和TEM观察结果显示样品金属镍是比较理想的球型,VSM测试结果表明Ni纳米球具有典型的铁磁性.  相似文献   
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The two-campus transport problem (TCTP) is a dial-a-ride problem with only two destinations. The problem is motivated by a transport problem between two campuses of an academic college. The two campuses are located in two different cities. Lecturers living in one city are sometimes asked to teach at the other city’s campus. The problem is that of transporting the lecturers from one campus to the other, using a known set of vehicles, so as to minimize the time the lecturers wait for their transport. We mathematically model the general TCTP, and provide an algorithm that solves it, which is polynomial in the number of lecturers. The algorithm is based on a reduction to a shortest path problem.  相似文献   
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Bibliometric analysis of publication metadata is an important tool for investigating emerging fields of technology. However, the application of field definitions to define an emerging technology is complicated by ongoing and at times rapid change in the underlying technology itself. There is limited prior work on adapting the bibliometric definitions of emerging technologies as these technologies change over time. The paper addresses this gap. We draw on the example of the modular keyword nanotechnology search strategy developed at Georgia Institute of Technology in 2006. This search approach has seen extensive use in analyzing emerging trends in nanotechnology research and innovation. Yet with the growth of the nanotechnology field, novel materials, particles, technologies, and tools have appeared. We report on the process and results of reviewing and updating this nanotechnology search strategy. By employing structured text-mining software to profile keyword terms, and by soliciting input from domain experts, we identify new nanotechnology-related keywords. We retroactively apply the revised evolutionary lexical query to 20 years of publication data and analyze the results. Our findings indicate that the updated search approach offers an incremental improvement over the original strategy in terms of recall and precision. Additionally, the updated strategy reveals the importance for nanotechnology of several emerging cited-subject categories, particularly in the biomedical sciences, suggesting a further extension of the nanotechnology knowledge domain. The implications of the work for applying bibliometric definitions to emerging technologies are discussed.  相似文献   
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The authors investigated the direct and interactive effects of the job demand– control–support (JDC-S) model’s components on subsequent changes in high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides (TRI) separately for male and female employees. In contrast to all 14 past studies on these relationships, the authors used a longitudinal design. Study participants (N = 1,137, 66% men) were all apparently healthy employees who underwent a routine health check at 2 points in time (Time 1 and Time 2) about 22 months apart. In these analyses, the authors controlled for the Time 1 level of each criterion and for other confounders. Most of the direct and moderating effects found did not support the predictions of the JDC-S model; this finding is in agreement with the majority of past cross-sectional studies. The authors did not find any evidence supporting the existence of a reverse causation for either of the components of the JDC-S model. The authors suggest that serum lipids may not be a physiological mechanism mediating the effects of the JDC-S model on atherosclerotic diseases. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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