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The integration of computers within the manufacturing environment has long been a method of enhancing productivity. Their use in many facets of a manufacturing enterprise has given industries the ability to deliver low-cost, high-quality competitive products. As computer technology advances, we find more and more uses for new hardware and software in the enterprise. Over a period of time, we have seen many “islands” of computer integration. Distinct, fully functional hardware and software installations are a common base for many industries. Unfortunately, these islands are just that, separate, distinct and functional but non-integrated. The lack of integration within these information systems make it difficult for end users to see the same manufacturing data. We are finding the need for a “single image” real-time information system to provide the enterprise with the data that is required to plan, justify, design, manufacture and deliver products to the customer. Unfortunately, many industries have a large installed base of hardware and software. Replacement of current systems is not a cost-justified business decision. An alternative would be the migration of current systems to a more integrated solution. The migration to a computer-integrated manufacturing (CIM)-based architecture would provide that single image real-time information system.

The effort and skills necessary for the implementation of a CIM-based architecture would require active participation from two key organizations: Manufacturing and information systems (I/S). The manufacturing engineers, process engineers and other manufacturing resource would be the cornerstone for obtaining requirements. The ability to effectively use I/S is a critical success factor in the implementation of CIM. I/S has to be viewed as an equal partner, not just as a service organization. Manufacturing management needs to understand the justification process of integrating computer systems and the “real” cost of integration versus the cost of non-integrated manufacturing systems. The active participation of both organizations during all phases of CIM implementation will result in a effective and useful integrated information system.  相似文献   

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Reassembly of enzymes from peptide fragments has been used as a strategy for understanding the evolution, folding, and role of individual subdomains in catalysis and regulation of activity. We demonstrate an oligomerization-assisted enzyme reassembly strategy whereby fragments are covalently linked to independently folding and interacting domains whose interactions serve to promote efficient refolding and complementation of fragments, forming active enzyme. We show that active murine dihydrofolate reductase (E.C. 1.5.1.3) can be reassembled from complementary N- and C-terminal fragments when fused to homodimerizing GCN4 leucine zipper-forming sequences as well as heterodimerizing protein partners. Reassembly is detected by an in vivo selection assay in Escherichia coli and in vitro. The effects of mutations that disrupt fragment affinity or enzyme activity were assessed. The steady-state kinetic parameters for the reassembled mutant (Phe-31 --> Ser) were determined; they are not significantly different from the full-length mutant. The strategy described here provides a general approach for protein dissection and domain swapping studies, with the capacity both for rapid in vivo screening as well as in vitro characterization. Further, the strategy suggests a simple in vivo enzyme-based detection system for protein-protein interactions, which we illustrate with two examples: ras-GTPase and raf-ras-binding domain and FK506-binding protein-rapamycin complexed with the target of rapamycin TOR2.  相似文献   
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The mathematical model of a new autooscillatory system with chaotic dynamics based on self-excitation of an anharmonic oscillator is considered. The results of numerical analysis show the possibility of generating chaotic oscillations with linear gain in the delayed feedback and controlling chaos by means of parametric self-action.  相似文献   
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Conducted a confirmatory test of I. Ajzen and M. Fishbein's (1980) theory of reasoned action as applied to the realm of moral behavior, using structural equation modeling. Ss were 1,056 male and female athletes (aged 10–18 yrs [M?=?14.5]). Ss completed a questionnaire that contained 2 hypothetical situations related to moral behavior in sports. For each situation, Ss completed scales assessing all components of the model. A modified version of the theory provided a significant improvement over the Ajzen and Fishbein model. This model retained the basic relationships postulated by the theory and added correlations between the attitudinal and normative structures and a causal path from normative beliefs to attitudes. This model was very robust, holding for the 2 situations. Implications for the construct validity of the theory of reasoned action and its application for moral behavior are drawn. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
996.
Conclusions The aging of concentrated spinning solutions of PM PAA polyamido acid has been investigated with the use of viscosimetry, exclusion liquid chromatography, and rheology.It has been found that the aging of PAA solutions is accompanied by reactions of further polycondensation and of transamidation. These reactions lead to a decrease in the polydispersity index and in structure-formation in the solution, which also causes the observed nonparallel change in intrinsic and effective viscosities of PAA solutions in the initial stages of the process.Translated from Khimicheskie Volokna, No. 3, pp. 15–17, May–June, 1987.  相似文献   
997.
Methylenetetrahydrofolate([H4] folate) dehydrogenase (D) and methenyl[H4] folate cyclohydrolase (C) coexist as a bifunctional enzyme (DC) or as the amino-terminal domain of a trifunctional enzyme (DCS) where the third activity is 10-formyl[H4]folate synthetase (S). Two crystal forms of the DC domain of the human cytosolic DCS enzyme have been grown from polyethyleneglycol solution. The monoclinic P2(1) crystals diffract to 2.8 A with a = 72.5 A, b = 68.5 A, c = 125.2 A, and beta = 91.8 degrees but were found to be twinned. The orthorhombic P2(1)2(1)2(1) crystals diffract to 2.5 A with a = 67.7 A, b = 135.9 A, c = 61.6 A, and contain two molecules per asymmetric unit.  相似文献   
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