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91.
This is the second of two papers surveying research in coordination approaches and systems. This paper is concerned with operational coordination, which is aimed at coordinating activities such that the design process can be performed in a near optimal manner with respect to time, and the allocation and utilisation of resources. Aspects of coordination categorised as operational include resource management, scheduling and planning. The first of these two papers presents a review of coordination from a strategic perspective, which is concerned with the decision management aspects of coordination. Greater emphasis is now being placed on the significance of organising the design process as this affects time to market, product quality, cost, and consequently product success. The aim of this paper is to present a fundamental review of operational coordination approaches and systems. The 1990s has seen much progress being made towards a greater understanding and appreciation of coordination in various disciplines through the development of a wide range of approaches and systems. However, there remains a requirement to formally identify the key issues involved in coordination such that a widely accepted representation can be agreed upon. Consequently, research should continue to be supported in the exploration for a unified approach to coordination which will permit a broader and greater understanding of those aspects involved.  相似文献   
92.
93.
Site monitoring is an indispensable procedure in construction quality control. It does not only minimize construction defects and human errors but also supports project team members making strategic decisions at critical points throughout the construction stages. This paper presents a cost-effective construction site monitoring system integrating a long-range wireless network, network cameras, and a web-based collaborative platform. The system supports simultaneous user access therefore project team members could view real-time captured images or video of a construction site, discuss and exchange ideas with gadgets such as video conference, text and shared whiteboard at a distance via the Internet. It was carefully configured in order to maintain the reliability under the reactive conditions of the construction sites. The system has been implemented and tested on two construction sites and promising results were obtained.  相似文献   
94.
95.
This field experiment examined effects of a support intervention on the physical and mental health of coronary artery bypass graft (CABG) surgery patients. Control participants (N?=?90) received usual hospital care; experimental participants (N?=?100) also received visits from a "similar other" while in the hospital. Similar others were Veterans Administration veterans who had CABG surgery previously and were trained in simple supportive techniques. Outcomes were assessed prior to surgery and at 1, 6, and 12 months afterwards. Unexpectedly, the intervention generally had no effects on participants' well-being. Further analysis showed that participants who talked often with fellow cardiac patients in the hospital ("de facto similar others") experienced improvements in their physical and emotional well-being over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
96.
Bill Boni 《Network Security》2002,2002(4):18-19
In what may turn out to be one of the most interesting incidents of early 21st century electronic business, a French company, Canal+ Group and two subsidiaries recently filed a lawsuit in US District Court for Northern California against NDS Group [NASDAQ:NNDS]. The basis for the complaint is that NDS, a UK-based company ‘spent large amounts of money and resources’ to break the security system underlying Canal+’s digital TV smartcard. The suit claims that NDS masterminded ‘a conspiracy to harm Canal+’s competitive position in the digital television market.’ The plaintiffs allege violations of US copyright law and the Racketeer Influenced and Corrupt Organizations Act, as well as the California Unfair Competition statute, all of which carry very serious penalties.  相似文献   
97.
98.
Bill 《Refocus》2004,5(5):56-57
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99.
[Fe]‐Hydrogenase (Hmd) catalyzes reversible hydride transfer from H2. It harbors an iron‐guanylylpyridinol as a cofactor with an FeII that is ligated to one thiolate, two COs, one acyl‐C, one pyridinol‐N, and solvent. Here, we report that CuI and H2O2 inactivate Hmd (half‐maximal rates at 1 μM CuI and 20 μM H2O2) and that FeII inhibits the enzyme with very high affinity (Ki=40 nM ). Infrared and EPR studies together with competitive inhibition studies with isocyanide indicated that CuI exerts its inhibitory effect most probably by binding to the active site iron‐thiolate ligand. Using the same methods, it was found that H2O2 binds to the active‐site iron at the solvent‐binding site and oxidizes FeII to FeIII. Also it was shown that FeII reversibly binds away from the active site iron, with binding being competitive to the organic hydride acceptor; this inhibition is specific for FeII and is reminiscent of that for the [FeFe]‐hydrogenase second iron, which specifically interacts with H2.  相似文献   
100.
A two-step doping strategy was applied to the synthesis of La0.9Sr0.1Ga0.8Mg0.2O2.85 (LSGM1020) powder by a gel combustion method. The Mg-doped LaGaO3 powder was prepared in the first step, and Sr incorporation in the Mg-doped LaGaO3 powder was done in the second step to obtain the final LSGM1020 powder. The two-step procedure is effective in preparing higher purity powders than the traditional one-step procedure. Rietveld refinement of X-ray powder diffraction (XRD) patterns shows that incorporation of Mg in LaGaO3 in the first step enlarges the LaGaO3 lattice: this facilitates the incorporation of Sr in the second doping step and thus high purity powder is obtained. Relatively phase pure LSGM1020 powder with only 3.1% of LaSrGaO4 was obtained after calcination at 1300 °C for 5 h. Therefore, the two-step doping strategy is an effective procedure for the preparation of LSGM powders with high Sr- and Mg-doping levels.  相似文献   
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