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101.
The notion of pseudorandomness is the theoretical foundation on which to consider the soundness of a basic structure used in some block ciphers. We examine the pseudorandomness of the block cipher KASUMI, which will be used in the next‐generation cellular phones. First, we prove that the four‐round unbalanced MISTY‐type transformation is pseudorandom in order to illustrate the pseudorandomness of the inside round function FI of KASUMI under an adaptive distinguisher model. Second, we show that the three‐round KASUMI‐like structure is not pseudorandom but the four‐round KASUMI‐like structure is pseudorandom under a non‐adaptive distinguisher model. 相似文献
102.
103.
Han-Jun Oh Jong-Ho Lee Hong-Joo Ahn Yongsoo Jeong Chang-Hoe Heo Choong-Soo Chi 《Journal of Electroceramics》2006,17(2-4):369-373
The characteristics and growth behaviors of alumina dielectric layer formed by anodic oxidation were investigated. The aluminum oxide layer anodized at 400 V was predominantly amorphous alumina, but at the applied potentials more than 500 V, amorphous and crystalline γ-alumina were existed in anodic oxide layer and the ratio of γ-alumina increased with the increasing applied potential. During the heat treatment at 600°C or higher temperature, amorphous alumina layer was transformed into the crystalline γ-alumina. The phase transition of anodic amorphous alumina into crystalline depends on anodic applied potentials and heat-treatment temperatures. 相似文献
104.
A facile method was developed to quantify unreacted ketene acetals during polymerization of poly(ortho ester)s. The method was based on isotopic (deuterium) labeling of the unreacted ketene acetal groups arising from the diketene acetal monomer, 3,9-diethylidene-2,4,8,10-tetraoxaspiro[5,5]undecane (DETOSU). In deuterium oxide, free ketene acetals are hydrolyzed to an α-deuterated ester; ortho ester bonds are hydrolyzed to the nondeuterated analog. The relative abundance of the deuterated ester side chain can be quantified by gas chromatography-mass spectrometry (GC-MS). In the current method, aliquots of a diketene acetal/polyol(s) reaction mixture were dissolved (crosslinked polymers swollen) in methylene chloride and excess D2O. The diketene acetal/polyol(s) reaction mixture was hydrolyzed under mildly acidic conditions to yield pentaerythritol dipropionate (PDP; hydrolysis product of DETOSU). PDP was extracted into an organic phase, silylated, and analyzed by GC-MS. Fragments corresponding to the C2H5C?O+ ion (57 a.m.u.) and C2H4DC?O+ ion (58 a. m. u.) were monitored and the quantity of free ketene acetal groups were calculated from the peak areas of the chromatograms. The precision of the method was ±0.1%. The accuracy, as compared to a parallel 1H-NMR study, was within 5%. This method permits determination of the cure end-point of a poly(ortho ester) polymerization reaction to within ±0.25%. The curing kinetics agreed well with DSC branching/crosslinking measurements. © 1994 John Wiley & Sons, Inc. 相似文献
105.
Sheng-Lueng Chung MuDer Jeng 《Robotics & Automation Magazine, IEEE》2004,11(3):14-21
In this paper, the scenario normalization technique is addressed, which is very useful in the context of generic equipment control, where an equipment-control system (ECS) is to control several pieces of equipment, possibly of different types. This paper begins with a background introduction to a photolithographic cell and the concept of generic equipment control adopted in semiconductor fabs. The concept of message modulation that translates in semantics context the sequence flows between the high-level ECS and the low-level equipment is presented. The main idea relies on the operational scenarios modeling by the sequence diagram; message translation based on semantics analysis; the derivation of production rules and the implementation of them on an event-triggering platform. Scenarios, thus obtained and presented to the high-level ECS by the coordinator, are then in compliance with the normalized scenario as required by the generic equipment controller. The significance of the proposed normalization techniques has the following implication: when different equipment are included in a cell operation, it is not necessary to rewrite control programs but to add relatively simpler transformation sequences enabling the use of the standard ECS function. From the control point of view, the controlled systems of stepper and track can be modeled as discrete event dynamic ones if operation coordination is considered. 相似文献
106.
Kum‐Il Lee Yong‐Sik Yim Sang‐Wook Chung Jiaqiu Wei Jong Il Rhee 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(9):1036-1045
A two‐dimensional (2D) spectrofluorometer was used to monitor various fermentation processes with recombinant E coli for the production of 5‐aminolevulinic acid (ALA). The whole fluorescence spectral data obtained during a process were analyzed using artificial neural networks, ie self‐organizing map (SOM) and feedforward backpropagation neural network (BPNN). The SOM‐based classification of the whole spectral data has made it possible to qualitatively associate some process parameters with the normalized weights and variances, and to select some useful combinations of excitation and emission wavelengths. Based on the classified fluorescence spectra a supervised BPNN algorithm was used to predict some of the process parameters. It was also shown that the BPNN models could elucidate some sections of the process's performance, eg forecasting the process's performance. Copyright © 2005 Society of Chemical Industry 相似文献
107.
Confidence measures are computed to estimate the certainty that target acoustic units are spoken in specific speech segments. They are applied in tasks such as keyword verification or utterance verification. Because many of the confidence measures use the same set of models and features as in recognition, the resulting scores may not provide an independent measure of reliability. In this paper, we propose two articulatory feature (AF) based phoneme confidence measures that estimate the acoustic reliability based on the match in AF properties. While acoustic-based features, such as Mel-frequency cepstral coefficients (MFCC), are widely used in speech processing, some recent works have focus on linguistically based features, such as the articulatory features that relate directly to the human articulatory process which may better capture speech characteristics. The articulatory features can either replace or complement the acoustic-based features in speech processing. The proposed AF-based measures in this paper were evaluated, in comparison and in combination, with the HMM-based scores on phoneme and keyword verification tasks using children’s speech collected for a computer-based English pronunciation learning project. To fully evaluate their usefulness, the proposed measures and combinations were evaluated on both native and non-native data; and under field test conditions that mis-matches with the training condition. The experimental results show that under the different environments, combinations of the AF scores with the HMM-based scores outperforms HMM-based scores alone on phoneme and keyword verification. 相似文献
108.
109.
Organic‐acid‐catalyzed sol–gel route for preparing poly(methyl methacrylate)–silica hybrid materials
Jui‐Ming Yeh Kuan‐Yeh Huang Chung‐Feng Dai B. G. Chand Chang‐Jian Weng 《应用聚合物科学杂志》2008,110(4):2108-2114
In this study, a series of organic–inorganic hybrid sol–gel materials consisting of a poly(methyl methacrylate) (PMMA) matrix and dispersed silica (SiO2) particles were successfully prepared through an organic‐acid‐catalyzed sol–gel route with N‐methyl‐2‐pyrrolidone as the mixing solvent. The as‐synthesized PMMA–SiO2 nanocomposites were subsequently characterized with Fourier transform infrared spectroscopy and transmission electron microscopy. The solid phase of organic camphor sulfonic acid was employed to catalyze the hydrolysis and condensation (i.e., sol–gel reactions) of tetraethyl orthosilicate in the PMMA matrix. The formation of the hybrid membranes was beneficial for the physical properties at low SiO2 loadings, especially for enhanced mechanical strength and gas barrier properties, in comparison with the neat PMMA. The effects of material composition on the thermal stability, thermal conductivity, mechanical strength, molecular permeability, optical clarity, and surface morphology of the as‐prepared hybrid PMMA–SiO2 nanocomposites in the form of membranes were investigated with thermogravimetric analysis, differential scanning calorimetry, dynamic mechanical analysis, gas permeability analysis, ultraviolet–visible transmission spectroscopy, and atomic force microscopy, respectively. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
110.
Ching‐Nan Chuang Liang Chao Ying‐Jie Huang Tar‐Hwa Hsieh Hung‐Yi Chuang Shu‐Chi Lin Ko‐Shan Ho 《应用聚合物科学杂志》2008,107(6):3917-3924
The synthesis of a p‐toluidine/formaldehyde (PTF) resin was performed, and the effects of the molar ratio of the individual monomers and the polymerization conditions on the structure of the PTF resin were studied. Fourier transform infrared and 13C‐NMR spectra were used to characterize the PTF. Wide‐angle X‐ray diffraction patterns revealed the crystalline structures of various PTFs. Polarized optical microscopy revealed that the molar ratio of the monomers had a strong effect on the crystalline morphologies. A longer polymerization time turned out a polymer with a higher intrinsic viscosity and molecular weight, which led to differences in the proton conductivity. All of the PTFs showed a higher proton conductivity than a commercial Nafion membrane at 90–100°C and 0% relative humidity. The proton conductivity of the PTF series could be improved by sulfonation with sulfuric acid and could be maintained after blending with polyurethane. Pure methanol could be used as a fuel source because of the insolubility and nonwetting properties of PTF in methanol to increase the output current density for a PTF membrane electrode assembly. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008 相似文献