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排序方式: 共有244条查询结果,搜索用时 15 毫秒
1.
Fuzzy inference, a data processing method based on the fuzzy theory that has found wide use in the control field, is reviewed. Consumer electronics, which accounts for most current applications of this concept, does not require very high speeds. Although software running on a conventional microprocessor can perform these inferences, high-speed control applications require much greater speeds. A fuzzy inference date processor that operates at 200000 fuzzy logic inferences per second and features 12-b input and 16-b output resolution is described 相似文献
2.
The previous discrete-model-based stability analysis of regional and national voting has been extended to a continuous-model-based analysis in the simultaneous presence of white and concentrated components of noise, reconfirming the previous conclusion that regional voting with smaller sized regions always demonstrates an improved stability over those with larger sized regions, including the national voting in its limiting case in particular. The conclusion remains valid as long as the weak distribution assumption is valid. 相似文献
3.
T. Kimura T. Tokuda Y. Nakada T. Nokajima T. Matsumoto A. Doucet 《Pattern Analysis & Applications》2013,16(1):55-67
Mixture models are ubiquitous in applied science. In many real-world applications, the number of mixture components needs to be estimated from the data. A popular approach consists of using information criteria to perform model selection. Another approach which has become very popular over the past few years consists of using Dirichlet processes mixture (DPM) models. Both approaches are computationally intensive. The use of information criteria requires computing the maximum likelihood parameter estimates for each candidate model whereas DPM are usually trained using Markov chain Monte Carlo (MCMC) or variational Bayes (VB) methods. We propose here original batch and recursive expectation-maximization algorithms to estimate the parameters of DPM. The performance of our algorithms is demonstrated on several applications including image segmentation and image classification tasks. Our algorithms are computationally much more efficient than MCMC and VB and outperform VB on an example. 相似文献
4.
Spodoptera frugiperda 21 (Sf21) insect cell-free protein synthesizing system was expanded to include nonnatural amino acids. Orthogonal tRNAs that work as carriers of nonnatural amino acids in the insect system were explored. Four-base codons for assigning the positions of nonnatural amino acids were also selected. Mutated streptavidin mRNAs that contained different four-base codons were prepared and added to the insect cell-free system in the presence of various tRNAs possessing the corresponding four-base anticodons. The tRNAs were chemically aminoacylated with various types of nonnatural amino acids to examine their incorporation efficiencies. Using p-nitrophenylalanine as the nonnatural amino acid and streptavidin as the target protein, tRNA sequences and the types of four-base codons were optimized to maximize the yield of the nonnatural mutant and to minimize production of full-length proteins that do not contain the nonnatural amino acid. Among the tRNA sequences taken from a variety of tRNAs of nonstandard structures, the tRNA derived from Methanosarcina acetivorans tRNA(Pyl) was the most efficient and orthogonal tRNA. Of the CGGN-type four-base codons, CGGA and CGGG were the most efficient ones for assigning the positions of nonnatural amino acids. p-Nitrophenylalanine and 2-naphthylalanine were efficiently incorporated as in the case of Escherichia coli and rabbit reticulocyte cell-free systems. Much less efficient incorporation was observed, however, for other nonnatural amino acids, indicating that the insect system is less tolerant to the structural diversity of amino acids than the E. coli cell-free system. 相似文献
5.
In this paper, for the calculation of the deformation behaviors of shape-memory alloy under multi-axial loading conditions with temperature changes, a two-dimensional mechanical model of polycrystalline shape memory alloy is constructed on the bases of the crystal plasticity and the deformation mechanism of shape memory alloy. In such a model, the orientation of crystal grain in the polycrystal and the loading direction can be considered. The deformation behaviors under some complex loading conditions are calculated with the model, and the results show that they are in good qualitative agreement with the experimental results. 相似文献
6.
The major outer membrane lipoprotein (Lpp) of Escherichia coli possesses serine at position 2, which is thought to function as the outer membrane sorting signal, and lysine at the C terminus, through which Lpp covalently associates with peptidoglycan. Arginine (R) is present before the C-terminal lysine in the wild-type Lpp (LppSK). By replacing serine (S) at position 2 with aspartate (D), the putative inner membrane sorting signal, and by deleting lysine (K) at the C terminus, Lpp mutants with a different residue at either position 2 (LppDK) or the C terminus (LppSR) or both (LppDR) were constructed. Expression of LppSR and LppDR little affected the growth of E. coli. In contrast, the number of viable cells immediately decreased when LppDK was expressed. Prolonged expression of LppDK inhibited separation of the inner and outer membranes by sucrose density gradient centrifugation, whereas short-term expression did not. Pulse-labeled LppDK and LppDR were localized in the inner membrane, indicating that the amino acid residue at position 2 functions as a sorting signal for the membrane localization of Lpp. LppDK accumulated in the inner membrane covalently associated with the peptidoglycan and thus prevented the separation of the two membranes. Globomycin, an inhibitor of lipoprotein-specific signal peptidase II, was lethal for E. coli only when Lpp possessed the C-terminal lysine. Taken together, these results indicate that the inner membrane accumulation of Lpp per se is not lethal for E. coli. Instead, a covalent linkage between the inner membrane Lpp having the C-terminal lysine and the peptidoglycan is lethal for E. coli, presumably due to the disruption of the cell surface integrity. 相似文献
7.
Melting and glass transition data are reported employing DSC for styrene-grafted high-density polyethylene obtained by γ radiation. Judging from the data of the melting point and the heat of fusion, the grafted polystyrene had no effect on the polyethylene crystallites, but the half-width of the thermogram was observed to increase slightly, showing an effect on the crystallite size distribution. As no effect was observed on the glass transition temperature by grafting, the amorphous region of the polyethylene apparently was not affected. It is suggested, therefore, that the free volume or segmental mobility will not be decreased by radiation-induced grafting. Very few but long grafted chains had negligible effect on the average polyethylene chain length available for segmental motion, and grafted polystyrene should be expected to differ little from the styrene homopolymer in thermal motions. 相似文献
8.
Maeda-Yamamoto M Saito T Nesumi A Tokuda Y Ema K Honma D Ogino A Monobe M Murakami A Murakami A Tachibana H 《Journal of the science of food and agriculture》2012,92(11):2379-2386
BACKGROUND: The purpose of this study was to evaluate the effects of leaf order or crop season on anthocyanins and other chemicals in the anthocyanin‐rich tea cultivar ‘Sunrouge’ (Camellia sinensis x C. taliensis) by using high‐performance liquid chromatography, and to study the effect of ‘Sunrouge’ extract on acetylcholinesterase (AChE) activity in human neuroblastoma SK‐N‐SH cells. RESULTS: The total anthocyanin content was higher in the third (3.09 mg g?1) than in the second (2.24 mg g?1) or first crop season (1.79 mg g?1). The amount of anthocyanins contained in the stem was high (1.61 mg g?1). In the third crop season, the concentrations of delphinidin‐3‐O‐β‐D ‐(6‐(E)‐p‐coumaroyl)galactopyranoside (DCGa), cyanidin‐3‐O‐β‐D ‐(6‐(E)‐p‐coumaroyl)galactopyranoside, delphinidin‐3‐O‐β‐D ‐galactopyranoside, delphinidin‐3‐O‐β‐D ‐(6‐O‐(Z)‐p‐coumaroyl)galactopyranoside, cyanidin‐3‐O‐β‐D ‐galactoside, and delphinidin‐3‐O‐β‐D ‐glucoside were 1.57 mg g?1, 0.52 mg g?1, 0.40 mg g?1, 0.22 mg g?1, 0.14 mg g?1, and 0.11 mg g?1, respectively. DCGa accounted for about 50% of the anthocyanins present. The suppressive effect of ‘Sunrouge’ water extract on AChE activity in human neuroblastoma SK‐N‐SH cells was the strongest among the three tea cultivars (‘Sunrouge’, ‘Yabukita’ and ‘Benifuuki’). CONCLUSION: These results suggested that ‘Sunrouge’ might protect humans from humans from AChE‐related diseases by suppressing AChE activity. To obtain sufficient amounts of anthocyanins, catechins and/or caffeine for a functional food material, ‘Sunrouge’ from the third crop season should be used. Copyright © 2012 Society of Chemical Industry 相似文献
9.
Yoshinori Nishiki Koichi Aoki Koichi Tokuda Hiroaki Matsuda 《Journal of Applied Electrochemistry》1987,17(1):67-76
On the basis of the observation of gas bubbles evolved by electrolysis, a two-dimensional vertical model cell composed of electrodes with open parts for releasing gas bubbles to the back side is proposed. The model cell consists of two layers. One layer forms a bubble curtain with a maximum volume fraction of gas bubbles in the vicinity of the working electrode with open parts. The other. being located out of the bubble layer, is a convection layer with a small volume fraction distributed in the vertical direction under forced convection conditions. The cell resistance and the current distribution were computed by the finite element method when resistivity in the back side varied in the vertical direction along the cell. The following three cases for overpotential were considered: no overpotential, overpotential of the linear type and overpotential of the Butler-Volmer type. It was found that the cell resistance was determined not only by the interelectrode gap but also by the percentage of open area and in some cases by the superficial surface area. The cell resistance varied only slightly with the distribution of the bubble layer in the back side.Nomenclature
b
linear overpotential coefficient given byb=/i
-
C
proportionality constant given by Equation 15
-
d
1
distance between front side of working electrode and separator
-
d
2
thickness of separator
-
F
Faraday constant
-
I
total current per half pitch
-
i
current density at working electrode
-
i
0
exchange current density
-
L
length of a real electrolysis cell
-
n
number of electrons transferred in electrode reaction
-
O
p
percentage of open area given by Equation 1
-
p
pitch, i.e. twice the length of the unit cell, defined by 2(BC) in Fig. 4
-
q
thickness of bubble curtain, defined by (AM) in Fig. 4
-
R
gas constant
-
r
t
total cell resistance
-
r
unit-cell resistance defined by (V – V
eq)/I
-
r
rs
residue ofr from sum ofr
0 andr
-
r
0
ohmic resistance of solution when0
p=0
-
r
resistance due to overpotential when0
p=0
-
s
electrode surface ratio or superficial surface area given by Equation 2 for the present model
-
T
absolute temperature
-
t
thickness of working electrode defined by EF in Fig. 4
-
V
cell voltage
-
V
eq
open circuit potential difference between working and counter electrodes
-
solution velocity in cell
- 0
solution velocity at bottom of cell
-
w
width of working electrode, defined by 2(DE) in Fig. 4
-
x
abscissa located on cell model
-
y
ordinate located on cell model
-
anodic transfer coefficient
-
linear overpotential kinetic parameter defined byb/[bc(p/2)]
- d
infinitesimally small length on the boundary
-
volume fraction of gas bubbles in cell
-
dimensionless cell voltage defined bynF(V – V
eq)/RT
-
overpotential at working electrode
-
Butler-Volmer overpotential kinetic parameter defined by [nFi
0bc(p/2)]/RT
-
coordinate perpendicular to boundary of model cell
- 1
resistivity of bubble-free solution
- 2
resistivity of separator
- bc
resistivity of bubble curtain
-
potential in cell 相似文献
10.
An optoelectronic self-oscillatory circuit with a constant time delay and its injection locking have been theoretically and experimentally described. The oscillation circuit incorporates a delayed feedback path by utilizing an optical fiber and is characterized by a differential-difference equation. The oscillation waveform and amplitude have been investigated by computing the equation. It is also shown that a stable frequency locking region exists and expands with an increase in the injection amplitude. By employing a carrier signal, two methods for optoelectronic oscillation, an AM and an FM type, are proposed and have been demonstrated to obtain more stable oscillation. 相似文献