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41.
Thermoplastic resin and fiber-reinforced thermo-plastics (FRTPs) were used without post-cure treatment as “molded material.” For such materials, creep behavior and physical aging occur simultaneously. This study examined the creep behavior of polycarbonate (PC) and glass-fiber-reinforced polycarbonate (GFRPC) injection moldings, including the effect of physical aging and fiber content, and determined that the time–temperature superposition principle could be applied to the creep behavior for different fiber contents. The effects of physical aging on creep behavior were evaluated quantitatively on pure resin and with various fiber contents without heat treatment. We found that the effect of physical aging could be evaluated with the proposed factor, “aging shift rate.” To discuss the linearity of viscoelasticity in FRTPs, this study used two shift factors: time and modulus shift factors. The fiber content affected creep behavior by both retarding and restraining it through changing the elastic modulus. This was shown by generating a grand master curve of creep compliance, which included the effects of time, temperature, and fiber content. Using the grand master curve of creep compliance and shift factors, it was possible to estimate the creep deformation of molded materials under varying conditions and fiber contents. The estimated creep deformation gave a very good fit to the experimental creep deformation.  相似文献   
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OBJECTIVE: To compare the influence of incongruent (asymmetric) follicular development on treatment outcome in IVF-ET and GIFT cycles. DESIGN: A retrospective comparative study. SETTING: Tertiary referral center for infertility. PATIENT(S): Five hundred forty-three consecutive assisted reproduction cycles (428 IVF-ET and 115 GIFT) in 422 infertile patients. INTERVENTION(S): Controlled ovarian hyperstimulation (COH) and IVF-ET or GIFT. MAIN OUTCOME MEASURE(S): The incongruity ratio as a parameter of the asymmetry in follicular development and pregnancy rate (PR). RESULT(S): For GIFT cycles, the PRs were 37.8% and 15.7% in cycles with congruent and incongruent follicular development, respectively. However, for IVF-ET cycles, the PR was not affected by incongruent follicular development: 28.2% and 29.0%, respectively. An inverse relationship was observed between the degree of incongruity and the estimated probability of pregnancy in GIFT cycles but not in IVF-ET cycles. Neither the side of the dominant ovary nor the degree of incongruity were consistent in consecutive cycles. CONCLUSION(S): Incongruent follicular development during COH has a significantly negative influence on the outcome of GIFT cycles but not on the outcome of IVF-ET cycles. The reason for this difference is not clear. We recommend considering IVF-ET instead of GIFT if incongruent follicular development occurs.  相似文献   
45.
We report the case of a 51-year-old Japanese man with a unique pustulosis. He had multiple erythematous plaques and numerous pinpoint pustules on the trunk and extremities resembling pustular psoriasis. Histologic features revealed a fully developed intraepidermal abscess filled with neutrophils and disrupted epidermal keratinocytes. Mild leukocytosclastic vasculitis was seen in the underlying dermis. A direct immunofluorescence study revealed IgM, Clq, C3 and fibrinogen deposits in the dermal vessels. The patient had also sternoclavicular hyperostosis. We think that this represents a unique type of pustular vasculitis distinct from pustular psoriasis.  相似文献   
46.
A high‐performance ambipolar light‐emitting transistor (LET) that has high hole and electron mobilities and excellent luminescence characteristics is described. By using this device, a conspicuous light‐confined edge emission and current‐density‐dependent spectral evolution are observed. These findings will result in broader utilization of device potential and they provide a promising route for realizing electrically driven organic lasers.  相似文献   
47.
We developed a fully automated electrophoresis system for rapid and highly reproducible protein analysis. All the two-dimensional (2D) electrophoresis procedures including isoelectric focusing (IEF), on-part protein staining, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and in situ protein detection were automatically completed. The system comprised Peltiert devices, high-voltage generating devices, electrodes, and three disposable polymethylmethacrylate (PMMA) parts for IEF, reaction chambers, and SDS-PAGE. Because of miniaturization of the IEF part, rapid IEF was achieved in 30 min. A gel with a tapered edge gel on the SDS-PAGE part realized a connection between the parts without use of a gluing material. A biaxial conveyer was employed for the part relocation, sample introduction, and washing processes to realize a low-maintenance and cost-effective automation system. Performances of the system and a commercial minigel system were compared in terms of detected number, resolution, and reproducibility of the protein spots. The system achieved high-resolution comparable to the minigel system despite shorter focusing time and smaller part dimensions. The resulting reproducibility was better or comparable to the performance of the minigel system. Complete 2D separation was achieved within 1.5 h. The system is practical, portable, and has automation capabilities.  相似文献   
48.
Géczy  Peter  Usui  Shiro 《Behaviormetrika》1999,26(1):89-106

The neural network rule extraction problem is aimed at obtaining rules from an arbitrarily trained artificial neural network. Recently there have been several approaches to rule extraction. Approaches to rule extraction implement a priori knowledge of data or rule requirements into neural networks before the rules are extracted. Although this may lead to a simplified final phase of acquitting the rules from particular type of neural networks, it limits the methodologies for general-purpose use. This article approaches the neural network rule extraction problem in its essential and general form. Preference is given to multilayer perceptron networks (MLP networks) due to their universal approximation capabilities. The article establishes general theoretical grounds for rule extraction from trained artificial neural networks and further focuses on the problem of crisp rule extraction. The problem of crisp rule extraction from trained MLP networks is first approached on theoretical level. Present ed theoretical results state conditions guaranteeing equivalence between classification by an MLP network and crisp logical formalism. Based on the theoretical results an algorithm for crisp rule extraction, independent of training strategy, is proposed. The rule extraction algorithm can be used even in cases where the theoretical conditions are not strictly satisfied; by offering an approximate classification. An introduced rule extraction algorithm is experimentally demonstrated.

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49.
Some kinetic characteristics and hydrolytic action patterns on various β-D -galactosyl-maltooligosaccharides (Gal-Gn), ranging in size from D.P. (degree of polymerization) 5 to 8, of an exo-maltotetraose-forming amylase of Pseudomonas stutzeri (G4-amylase) were examined to produce a few p-nitrophenyl β-D -galactosyl-α-maltooligosaccharides (Gal-GnP, n = 4,5). The relative hydrolytic reaction rates for larger Gal-Gn by the enzyme were larger than those for smaller saccharides tough the values for unmodified linear maltooligosachharides were almost same. Michaelis constants (Km) for hydrolysis of Gal-G4, Gal-G5, Gal-G6 and Gal-G7 by the enzyme were 1.3, 1.9, 1.3 and 1.3mM, and apparent molecular activities (ko) for these saccharides were 5.9, 38, 91 and 126s−1, respectively. The values of ko/Km for them were remarkably smaller than those for unmodified linear maltooligosaccharides. The G4-amylase cleaved 2 points of the α-1,4-glucosidic linkage in β-1,4-Gal-G4 to give β-1,4-Gal-G2 and -Gal-G3 in the molar ratio of 3:1, whereas the enzyme attacked 3 points of the linkage in β-1,4-Gal-G5, -Gal-G6 and -Gal-G7 to form β-1,4-Gal-G2,-Gal-G3 and Gal-G4 in the molar ratios of 2:5:1, 1:3:6 and 1:3:6, in the early stage of the reaction, respectively. On the other hand, the enzyme showed no action on β-1,6-Gal-G4 and formed β-1,6-Gal-G4 solely from β-1,6-Gal-G5, and β-1,6-Gal-G4 and -Gal-G5 were from β-1,6-Gal-G6 and -Gal-G7 in the ratios of 8:1 and 2:1, respectively. The enzyme also catalyzed the transfer action to produce Gal-G3P, Gal-G4P and Gal-G5P, of which the formation ratio was coincided well with the hydrolytic action pattern on each Gal-Gn, from Gal-Gn tested as a donor and p-nitrophenyl α-glucoside (GP) as an acceptor in an aqueous solution containing 40% (v/v) methanol. By using this novel reaction, Gal-G5P is now producing on an industrial scale to apply as a substrate for the assay of human α-amylase.  相似文献   
50.
Gamut mapping is a color transformation technique to solve a problem caused by mismatch of gamuts among imaging devices. One plausible goal of gamut mapping is to find a reproduction that is perceptually closest to the corresponding original image when an exact color matching is not possible. Several measures to quantify the perceptual difference between images have been proposed and applied to the gamut mapping problem. However most of the measures, such as average color difference, are applied on a pixel‐wise basis and show poor correlation with human visual perception. This article describes a model of the perceptual image difference for a given pair of images, which takes the human's contrast sensitivity into account and applies the model to a gamut mapping for generating a reproduction with minimum perceptual image difference. The model has a multispatial‐frequency channel structure with tunable peak gains for each channel, which are determined by psychophysical experiments, so that the model output fits the observer's sensitivity to the image difference. A gamut‐mapped image with minimum perceptual image difference is obtained by an iterative minimization process. To evaluate the proposed method, subjective evaluation experiments are performed to construct ratio scales that measure perceptual image difference of gamut‐mapped reproductions generated by the proposed and pixel‐wise methods. Results show that the reproductions by the proposed method are perceived as perceptually closest to the original, and the model's estimate of perceptual difference correlates better with the experimentally measured perceived image difference than other pixel‐wise measures. © 1999 John Wiley & Sons, Inc. Col Res Appl, 24, 280–291, 1999  相似文献   
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