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91.
A micromirror with large rotation angle and vertical displacement is proposed and developed. The proposed micromirror is actuated by newly developed prestress comb drive actuators, which exhibit no pull-in, no hysteresis, and large vertical displacement range characteristics. The micromirror was fabricated using commercially available PolyMUMPs. Experimental results indicated that the maximum rotation angle and vertical displacement of the device are 26 and 45 mum, respectively  相似文献   
92.
In this paper, the exact stability bound for discrete multiple time-delay singularly perturbed systems is examined. The obtained results, based on state space approach for the critical stability criterion of discrete systems, are sufficient conditions for the original system and its reduced subsystems about stability problems. Besides, we show that the subsystems are, indeed, zero-order approximations to the original systems. An example is given to illustrate the proposed schemes.  相似文献   
93.
Based on Lee-Lu-Lee's array multipliers and the RESO method, a concurrent error detection scheme in array multipliers for GF(2m ) fields is presented and only one clock cycle is added. The fault tolerant capability in such array multipliers is also included and only two extra clock cycles are required  相似文献   
94.
Protein concentrates from jatropha (JPC) and soy seeds (SPC) were obtained by solubilization and acid precipitation of proteins. JPC and SPC films were prepared by the casting method, using two different montmorillonite (MMT) clay concentrations and plasticized with glycerol. Film properties were evaluated by scanning electron microscopy, transmission electron microscopy, X‐ray diffraction (XRD), Fourier transform infrared spectroscopy, thermogravimetric analysis, tensile properties, water retention, and water vapor transmission rate (WVRT). Typical tactoid microcomposite structures were found to be heterogeneously dispersed in the films containing MMT. A small XRD peak was found in films with MMT. Slight improvements in thermal stability and tensile strength were observed in the films with MMT. Reductions in water retention and WVRT were obtained when MMT was added into the films. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44459.  相似文献   
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The regulation of would healing is one of the most important fields of research in ophthalmology today. Rabbit corneal fibroblast cultures were used to study the effects of interleukin-1 (IL-1) blockers on the proliferation of fibroblasts which is closely related to the wound healing. It was found that IL-1 blockers, such as CK-17, CK-101A, CK-2 and CK-103A, suppress fibroblast proliferation in a concentration-dependent manner. DNA synthesis was significantly inhibited by CK-17 and CK-103A but not by CK-101A and CK1-102. Although the synthesis of mRNA was reduced by all CK-compounds at most concentration tested, the synthesis of protein was only slightly reduced or unaffected. These results indicate that CK-compounds are potent fibroblast inhibitors but not cytolytic agents.  相似文献   
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The Aspergillus flavus group covers species of A. flavus and Aspergillus parasiticus as aflatoxin producers and Aspergillus oryzae and Aspergillus sojae as koji molds. Genetic similarity among these species is high, and aflatoxin production of a culture may be affected by cultivation conditions and substrate composition. Therefore, a polymerase chain reaction (PCR)-mediated method of detecting the aflatoxin-synthesizing genes to indicate the degree of risk a genotype has of being a phenotypic producer was demonstrated. In this study, 19 strains of the A. flavus group, including A. flavus, A. parasiticus, A. oryzae, A. sojae, and one Aspergillus niger, were subjected to PCR testing in an attempt to detect four genes, encoding for norsolorinic acid reductase (nor-1), versicolorin A dehydrogenase (ver-1), sterigmatocystin O-methyltransferase (omt-1), and a regulatory protein (apa-2), involved in aflatoxin biosynthesis. Concurrently, the strains were cultivated in yeast-malt (YM) broth for aflatoxin detection. Fifteen strains were shown to possess the four target DNA fragments. With regard to aflatoxigenicity, all seven aflatoxigenic strains possessed the four DNA fragments, and five strains bearing less than the four DNA fragments did not produce aflatoxin. When peanut kernels were artificially contaminated with A. parasiticus and A. niger for 7 days, the contaminant DNA was extractable from a piece of cotyledon (ca. 100 mg), and when subjected to multiplex PCR testing using the four pairs of primers coding for the above genes, they were successfully detected. The target DNA fragments were detected in the kernels infected with A. parasiticus, and none was detected in the sound (uninoculated) kernels or in the kernels infected with A. niger.  相似文献   
100.
This paper presents a floor-wall and ceiling (FWC) approach to determining the tool axes for five-axis pocket machining. The FWC method generates tool axes by simply linking the corresponding points between tool location paths on floor and tool axial paths on ceiling. The geometry of the floor, wall, and ceiling of a pocket are first discussed. The construction and manipulations of the tool location paths and the tool axial paths are then addressed. The relationship between the tool axis variation and the manipulations is analyzed such that the generated tool axes are guaranteed to be smooth, optimized, and collision-free. By using the FWC method, the complexity of determining the tool axes can be significantly reduced. Computer illustrations and example demonstrations are shown in this paper. The results reveal that the FWC method can generate much higher quality tool axes than the traditional methods.  相似文献   
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