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91.
Entropy in a fuzzy set measures the amount of ambiguity/imprecision present in the fuzzy set. In this paper, we introduce a knowledge measure of a fuzzy set and its generalization (accuracy measure). The knowledge measure may be considered as a dual measure of fuzzy entropy. We also investigate the effectiveness and application of the proposed knowledge measure in multiple attribute decision making. Furthermore, we provide a result for obtaining a class of knowledge measure. We also prove a general method for obtaining a knowledge measure using accuracy measure. Among some suggested implications of the proposed fuzzy accuracy measure, we demonstrate the application of fuzzy accuracy measure in image thresholding.  相似文献   
92.
A work of architecture is experienced at many different levels, and yet all too often, preconceived notions of style and form at the largest scale are generated initially and become the operative focus of a given project. Carefully considered moments and rich tactile articulation on a human scale are all but lost to image-oriented design that glorifies the building as an object. It is the design of these component elements and the methodology according to which they are constructed and integrated into the whole that interest me. I believe that alternative design methodologies that analyze the role and function of the detail must be explored and elaborated.  相似文献   
93.
Coexpression of two classes of folding accessory proteins, molecular chaperones and foldases, can be expected to improve the productivity of soluble and active recombinant proteins. In this study, horseradish peroxidase (HRP), which has four disulfide bonds, was selected as a model enzyme and overexpressed in Escherichia coli. The effects of coexpression of a series of folding accessory proteins (DnaK, DnaJ, GrpE, GroEL/ES, trigger factor (TF), DsbA, DsbB, DsbC, DsbD, and thioredoxin (Trx)) on the productivity of active HRP in E. coli were examined. Active HRP was produced by very mild induction with 1 μM isopropyl-β- -thiogalactopyranoside (IPTG) at 37°C, whereas the amount of active HRP produced by the induction with 1 mM IPTG was negligibly small. Active HRP production was increased significantly by coexpression of DsbA-DsbB (DsbAB) or DsbC-DsbD (DsbCD), while coexpression of molecular chaperones did not improve active HRP production. The growth of E. coli cells was inhibited significantly by the induction with 1 mM IPTG in a HRP single expression system. In contrast, when HRP was coexpressed with DsbCD, the growth inhibition of E. coli was not observed. Therefore, coexpression of Dsb proteins improves both the cell growth and the productivity of HRP.  相似文献   
94.
The creep properties, that is, the velocity constant, activation energy, stress index, and time index, of a test piece (TP) cut from a glass‐fiber‐reinforced nylon 6 product were successfully determined by a compression creep test. In the determination of the creep properties, the experimental creep curves for the TP were fitted by finite element analysis (FEA). Fiber‐reinforced nylon 6 beams with different fiber orientations were also prepared, and their creep properties were successfully determined by a combination of the bending creep test and the corresponding analysis. The creep behavior of the press‐fit component composed of a metal collar and a fiber‐reinforced nylon 6 product was predicted by FEA with the determined creep properties of the TP. The predicted retention forces were in good agreement with the experimental ones. The effects of the fiber orientation on the long‐term reliability of the press‐fit component are also discussed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   
95.
Conductive network formation and its dynamic process for multiwalled carbon nanotubes (MWNTs) and carboxyl‐tethered MWNT (MWNT‐COOH) filled poly(vinylidene fluoride)(PVDF) systems were investigated. Based on real‐time tracing the variation of electrical resistivity of systems with isothermal treatment time, the conductive network formation was evaluated. It was found that the conductive network formation was temperature and time dependent. The percolation time, characterized at a certain annealing time where the electrical resistivity started to decrease drastically, decreased with the increase of the filler concentration or the annealing temperature. However, the values of the percolation time and the activation energy of conductive network formation for the PVDF/MWNT‐COOH system were higher than those of the PVDF/MWNT system, indicating that the interaction between MWNTs and PVDF molecules played an important role in the conductive network formation of the composites. Furthermore, a modified thermodynamic percolation model was proposed to predict the percolation time of PVDF/MWNT composites. It was found that the calculated results fit the experimental data very well. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
96.
The detonation propagation phenomena in curved channels were experimentally studied in order to determine the stable propagation condition. A stoichiometric ethylene–oxygen mixture gas and five types of rectangular-cross-section curved channels with different inner radii of curvature were employed. The detonation waves propagating through the curved channels were visualized using a high-speed video camera. Multi-frame short-time open-shutter photography (MSOP) was developed in the present study to simultaneously observe the front shock shape of the detonation wave and the trajectories of triple points on the detonation wave. The detonation wave became more stable under the conditions of a higher filling pressure of the mixture gas and/or a larger inner radius of curvature of the curved channel. The critical condition under which the propagation mode of the detonation wave transitioned from unstable to stable was having an inner radius of curvature of the curved channel (ri) equivalent to 21–32 times the normal detonation cell width (λ). In the stable propagation mode, the normal detonation velocity (Dn) increased with the distance from the inner wall of the curved channel and approached the velocity of the planar detonation propagating through the straight section of the curved channel (Dstr). The smallest Dn was observed on the inner wall and decreased with decreasing ri/λ. The distribution of Dn on the detonation wave in the stable mode was approximately formulated. The approximated Dn given by the formula agreed well with the experimental results. The front shock shape of the detonation wave could be reconstructed accurately using the formula. The local curvature of the detonation wave (κ) nondimensionalized by λ decreased with increasing distance from the inner wall. The largest λκ was observed on the inner wall and increased with increasing ri/λ. Dn/Dstr decreased with increasing λκ. This nondimensionalized Dnκ relation was nearly independent of ri/λ.  相似文献   
97.
Lantibiotics are a unique type of antimicrobial peptide produced by a large number of gram-positive bacteria that contain unusual amino acids, such as lanthionine and dehydrated amino acids. Ribosomally synthesized lantibiotic prepeptide consists of an N-terminal leader peptide followed by a C-terminal propeptide moiety that undergoes several post-translational modification events to yield a biologically active lantibiotic. Research on lantibiotics has drawn much attention in recent years and has undergone extensive progress as a step forward to the next paradigm. Unusual amino acids in lantibiotics solely contribute to their biological activity and also enhance their structural stability. Thus, enzymes involved in lantibiotic biosynthesis would have a high potential for peptide engineering by introducing unusual amino acids into desired peptides, which may establish a universal approach to advance the structural design of novel peptides, termed lantibiotic engineering. In this review, we focus on recent development with contemporary innovations and perspective of lantibiotic research.  相似文献   
98.
99.
Stable nitroxyl radical polymers, such as poly (2,2,6,6-tetramethyl-1-piperidinyloxy-4-yl methacrylate) (PTMA), are known to be effective as cathode active materials for lithium rechargeable batteries. A water-based slurry was used to prepare PTMA composite electrodes, enabling successful production of homogeneous electrodes. This improved utilization of active material and enabled us to obtain specific capacities almost equal to the theoretical value (111 mAh g−1). Lithium half cells were fabricated using these electrodes and using graphite as the anode active material, and their cycling stability, temperature dependence, rate capability and self-discharge rate were measured in detail. Although they showed 24% irreversible capacity on the first cycle, the capacity stabilized after the second cycle.  相似文献   
100.
继续前报内容介绍高速纺丝Nylon6纤维的结构和性能:密度随纺丝速度而变化,以有纤维的X射线衍射图像,晶型和力学性质。  相似文献   
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