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81.
The reuse of business-process and information specifications can reduce the cost of business design by helping to alleviate bottlenecks in the development of workflow systems. Using a new concept we call workflow design pattern, we create a library of standard business-process and information specifications to be used as workflow business template. Business design and system design are done by customizing the standard specifications. New support tools are used to implement the design result. By using this proposed method, the cost of system development can be reduced.  相似文献   
82.
A new type of software system for an industrial sequence controller is proposed. In this system, a control program is described with the Petri net-like language named Control-net (C-net). This language improves control software maintainability and flexibility. An efficient C-net interpretation schema for real-time control is presented and an overhead time evaluation model of the proposed schema is developed. Through the model analysis and measurement of the response time of an interpreter on a microcomputer, it is proved that the interpretation schema satisfies the required response time. Finally, a microcomputer based controller named Station Controller (SCR) in which the presented C-net interpreter was installed is described and several applications of this controller to real systems are illustrated.  相似文献   
83.
A gradient-index (GRIN) plastic optical fiber was prepared by a heat-drawing process of the GRIN preform rod obtained by a new interfacial-gel copolymerization technique. The attenuation loss of the GRIN fiber was 179 kB/km at 650-nm wave-length and its numerical aperture was 0.20-0.25. To attain low loss and highly dense integrated circuits, steric radial-GRIN optical waveguide components such as GRIN branching, star coupler, multi-coupler, and a 2-D GRIN lens array, were monolithically fabricated by this technique. A novel spherical GRIN sphere lens, whose index function is symmetrical about the center of the sphere, with a low spherical aberration, was prepared by a modified suspension polymerization technique. A W-shaped GRIN sphere has been newly proposed to further reduce the spherical aberration, compared with the parabolic GRIN sphere previously proposed.  相似文献   
84.
End-carboxylated telechelic poly(ε-caprolactone)s (XPCLs) with different molecular weights were blended into a triblock copolymer of styrene–(epoxidized butadiene)–styrene (ESBS) to investigate the curing behaviour and the mechanical properties of the XPCL/ESBS binary reactive blend. It was found that the time–torque cure curve showed a significant torque increase after a very short induction period, in which the degree of the torque increase depended on the molecular weight of XPCL. This indicates that substantial crosslinking reaction takes place between the XPCLs and the epoxidized polybutadiene of the ESBS. Stress–strain curves of the blends after cure depended on the molecular weight of XPCL and the blend ratio. The XPCL/ESBS blends had sufficient thermal stability to show elastomeric behaviour at elevated temperature above the glass transition of the styrene domains of ESBS because of formation of crosslinking points between unlike polymer components by the reactive blending. © 1999 Society of Chemical Industry  相似文献   
85.
A novel type of monoamine oxidase (EC. 1.4.3.4) present in the liver of skipjack tuna (Katsuwonus pelamis) was extracted from mitochondrial preparations by Triton X-100. The enzyme was purified by ammonium sulphate fractionation, followed by Sephadex G-200, butyl-toyopearl 650 M, phenyl-toyopearl 650 M and hydroxyapatite chromatography. The molecular weight of the enzyme was estimated to be about 110000 by gel filtration on Sephadex G-200. The enzyme was activated by Mn2+, but was inhibited by Cu2+, Zn2+ and p-chloromercuribenzoic acid (PCMB). Furthermore, the enzyme was completely inhibited by Hg2+ and 5,5′-dithiobis(2-nitrobenzoic acid) (DTNB). © 1997 SCI.  相似文献   
86.
Drag reduction characteristics of trimethylolethane hydrate slurries treated with surfactants have been investigated. The effects of the surfactant concentration and hydrate fraction of the slurry on drag reduction behaviors were focused on in this paper. The friction coefficient in a pipe flow of hydrate slurries treated with surfactants and the relaxation time of trimethylolethane solution with surfactants were measured. From the results, it was found that the effective drag reduction appears in the cases of high surfactant concentration even in cases of high hydrate fraction. This behavior was supported by the viscosity shear-thickening occurrence reported in the previous study. However, the effective drag reduction disappears in the cases of low surfactant concentration in spite of the shear-thickening occurrence. On this discrepancy, the relaxation time of the solution was measured. It is found that the critical concentration determined from the relaxation time disappearance well corresponds to the limitation of effective drag reduction occurrence.  相似文献   
87.
Thermoelectric properties of Sn1−xyTiy SbxO2 ceramics were investigated in detail. The addition of Sb into SnO2 matrix increased the electric conductivity, σ. The increase in the σ value should be caused by the increase in the carrier concentration. The Seebeck coefficients of all the samples were negative, which means that these samples have n-type conduction. The samples of this study have porous structure. The maximum Z value of all the samples measured in this study was 2.4 × 10−5 K−1.  相似文献   
88.
Buckwheat grain has well‐balanced nutritional value, whereas its digestibility is relatively low. This review summarizes recent advances in studies on the hypolipidemic activity of buckwheat. The most remarkable function is a powerful hypocholesterolemic activity of buckwheat protein in rats, which is far stronger than that of soy protein. The cholesterol‐lowering effect is mediated by mechanisms involving higher excretion of fecal sterols and lower digestibility of buckwheat protein. The insoluble fraction of buckwheat protein associates with cholesterol and reduces micelle cholesterol uptake in caco‐2 cells. Furthermore, consumption of buckwheat protein suppresses cholesterol‐induced gallstones and body fat in rodents. Buckwheat sprouts also have hypolipidemic activity in rats or type 2 diabetic mice. Tartary buckwheat bran extract reduced the serum level of total cholesterol and triglyceride in hyperlipidemic rats. The consumption of buckwheat seed reduced low‐density lipoprotein cholesterol in the pastureland Mongolian population. Taken together, buckwheat may be beneficial for prevention of hyperlipidemia. © 2014 Society of Chemical Industry  相似文献   
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