• International Journal of Precision Engineering and Manufacturing
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• v.2 no.1
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• pp.26-32
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• 2001

An ecpert system for rotationally symmetric deep drawing products has been developed. The application for non-axisymmetric components, however, has not been reported yet. This study construsctus and expert system for non-axisymmetric motor frame which shape is classified into ellipse in deep draqing process and investigates process sequence design with elliptical shape. The developed system consists of four modules. The first is recognition of calculate surface area for non-axisymmetric products. The third is blank design module the creates an oval-shaped blank with the same surface area. The fourth is a processplanning module based on production rules that play the best important roles in an expert system for manufacturing .The production rules are generated and upgraded by interviewing field engineers. Especially, drawing coefficient, punch and die radii for elliptical shape products are considered as main design parameters. The constructed system for elliptical deep drawing product would be very useful to reduce lead time and improve accuracy for products.

• Environmental and Resource Economics Review
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• v.11 no.3
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• pp.415-446
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• 2002

Due to its cost effectiveness, tradeable emission permits (TEP) system has been effectively used in the USA and many other advanced countries. But, academic many researchers have been argued that TEP system would not work as an efficient regulatory tools when there are imperfect competition in permits and/or products markets. Sartzetakis (1997), however, show that TEP system can serve as an effective environmental regulation under the certain demand/cost conditions even though duopolistic production market is not competitive. In this paper we extend Sartzetakis's analysis into the differentiated products markets under the same cost conditions, and examine the relative efficiency of TEP system by comparing it with the command and control system. We then show that the main results of Sartzetakis can hold if two differentiated products markets have the symmetric demands. In particular, it is revealed that social welfare will be increased under TEP system even though consumer surplus may be decreased.

• Journal of the Korean Mathematical Society
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• v.50 no.2
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• pp.275-306
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• 2013

For two positive integers $m$ and $n$, let $\mathcal{P}_n$ be the open convex cone in $\mathbb{R}^{n(n+1)/2}$ consisting of positive definite $n{\times}n$ real symmetric matrices and let $\mathbb{R}^{(m,n)}$ be the set of all $m{\times}n$ real matrices. In this paper, we investigate differential operators on the non-reductive homogeneous space $\mathcal{P}_n{\times}\mathbb{R}^{(m,n)}$ that are invariant under the natural action of the semidirect product group $GL(n,\mathbb{R}){\times}\mathbb{R}^{(m,n)}$ on the Minkowski-Euclid space $\mathcal{P}_n{\times}\mathbb{R}^{(m,n)}$. These invariant differential operators play an important role in the theory of automorphic forms on $GL(n,\mathbb{R}){\times}\mathbb{R}^{(m,n)}$ generalizing that of automorphic forms on $GL(n,\mathbb{R})$.

• Journal of the Korean Applied Science and Technology
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• v.14 no.2
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• pp.57-64
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• 1997

The symmetric naphthothiazolo carbocyanine is of industrial importance as green-sensitizing dye in the spectral sensitization of emulsion microcrystals in negative film-making. In this study, green-sensitizing dye was prepared by the reaction of 2-methyl-3-sulfopropyl-5-phenyl-benzoxazolium(inner salt) with triethyl orthoacetate in the presence of triethylamine. The product was identified by using various analytical tools such as Elemental analyzer, IR spectrophotometer, UV-Vis spectrophotometer, $^1H$-NMR spectrometer, TGA and DSC. The maximum absorption peak in methanol solvent was 502nm. Therefore, it was concluded that benzoxazolo carbocyanine dye can be used as green-sensitizing dye for the spectral sensitization of photographic emulsion.

• Korean Journal of Pharmacognosy
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• v.9 no.1
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• pp.1-9
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• 1978

The principle of Fourier Transform Nuclear Magnetic Resonance and its usefulness in the fields of pharmacy and biological sciences are described. 1. The $^1H\;and\;^{13}C$ NMR spectra of triostin A and its mixture with purine derivatives were taken. From the analysis of the spectra it has established that triostin A, which exists in two symmetric conformers in chloroform solution, forms complexes only with purine derivatives by the participation of one of the conformers. 2. Also, the $^{13}C$ NMR spectra of "intact" substances in the field of pharmacognosy were taken. From the spectra it was suggested that the method is very useful for natural product research in cooperation with the chemical method.

• Membrane Journal
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• v.30 no.1
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• pp.9-20
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• 2020

Membranes are used in most processes of biopharmaceutical production. It is used for pretreatment of other processes, separation of impurities in the process, virus removal, control of products concentration and buffer solution exchange. Virus filters play an important role in ensuring product efficacy and stability because viral contamination of biopharmaceuticals for humans is a sensitive issue that is directly related to serious clinical outcomes. Virus filters typically have complex multilayer structures made of various polymers such as surface-modified PVDF, PES, CRC. Depending on the manufacturer, filters have different pore structures and shapes, such as symmetric or asymmetric, and is used in the form of pleated membrane, flat sheets or hollow fibers. Virus filters are exclusively supplied by few foreign companies such as Asahi Kasei, Millipore, Pall and Sartorius. Replacing virus filters can be time consuming and expensive, including approval from regulatory agencies through validation. As localization has become important due to Japan's recent export regulations, it is necessary to increase the degree of technical independence.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.49 no.1
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• pp.19-30
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• 2012

For digital data compression, the quantization is the main part of the lossy source coding. In order to improve the performance of quantization, the vector quantizer(VQ) can be employed. The encoding complexity, however, exponentially increases as the vector dimension or bit rate gets large. Much research has been conducted to alleviate such problems of VQ. Especially for high bit rates, a constrained VQ, which is called the sample-adaptive product quantizer(SAPQ), has been proposed for reducing the hugh encoding complexity of regular VQs. SAPQ has very similar structure as to the product VQ(PQ). However, the quantizer performance can be better than the PQ case. Further, the encoding complexity and the memory requirement for the codebooks are lower than the regular full-search VQ case. Among SAPQs, 1-SAPQ has a simple quantizer structure, where each product codebook is symmetric with respect to the diagonal line in the underlying vector space. It is known that 1-SAPQ shows a good performance for i.i.d. sources. In this paper, a study on designing 1-SAPQ for the first-order Markov process. For an efficient design of 1-SAPQ, an algorithm for the initial codebook is proposed, and through the numerical analysis it is shown that 1-SAPQ shows better quantizer distortion than the VQ case, of which encoding complexity is similar to that of 1-SAPQ, and shows distortions, which are close to that of the DPCM(differential pulse coded modulation) scheme with the Lloyd-Max quantizer.

• International Area Studies Review
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• v.12 no.3
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• pp.467-492
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• 2008

This paper analyzes the specific product-basis trade structure between Busan and Japan using the recent 2000-2007 trade statistical data. Several specific product-basis trade structure tests such as intra-industry trade index and market comparative advantage index show that there are considerable differences in intra-industry trade structure between Busan and Japan. Furthermore, this paper found that Busan has high quality vertical intra-industry trade and horizontal intra-industry trade as well as low quality vertical intra-industry trade in trading with Japan. While Busan has the market comparative disadvantage in automobile-part products in Japan. This paper also examines the contribution to trade balance of Busan's exports and the movement of Busan's comparative advantage patterns in Japan. The comparative advantage appears to have overall stability and convergence properties using symmetric indices.

• Journal of applied mathematics & informatics
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• v.32 no.1_2
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• pp.285-295
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• 2014

In the setting of semidenite linear complementarity problems on $S^n$, we focus on the Stein Transformation $S_A(X)\;:=X-AXA^T$, and show that $S_A$ is (strictly) monotone if and only if ${\nu}_r(UAU^T{\circ}\;UAU^T)$(<)${\leq}1$, for all orthogonal matrices U where ${\circ}$ is the Hadamard product and ${\nu}_r$ is the real numerical radius. In particular, we show that if ${\rho}(A)$ < 1 and ${\nu}_r(UAU^T{\circ}\;UAU^T){\leq}1$, then SDLCP($S_A$, Q) has a unique solution for all $Q{\in}S^n$. In an attempt to characterize the GUS-property of a nonmonotone $S_A$, we give an instance of a nonnormal $2{\times}2$ matrix A such that SDLCP($S_A$, Q) has a unique solution for Q either a diagonal or a symmetric positive or negative semidenite matrix. We show that this particular $S_A$ has the $P^{\prime}_2$-property.

• 한국연소학회:학술대회논문집
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• 2000.05a
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• pp.122-132
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• 2000

Computational fluid dynamic simulation is performed for the floating turbulent premixed flames stabilized in stagnation flows of Cho et al. [1] and Cheng and Shepherd [2]. They are both in the wrinkled flamelet regime far from the extinction limit with $u'/S^{0}_{L}$ less than unity. The turbulent flux is given in the first moment closure as a sum of the classical gradient flux due to turbulent motions and the countergradient flux due to thermal expansion. The parameter $N_{B}'s$ are greater than unity with the countergradient flux dominant over the gradient flux. The countergradient flux is assumed to be zero in $\bar{c}<0.05$. The flame surface density is modeled as a symmetric parabolic function with respect to $\bar{c}$. The product of the maximum flame surface density and the mean stretch factor is considered as a tuning constant to match the flame location. Good agreement is achieved with the measured $\tilde{w}$ and $\bar{c}$ profiles along the axis in both flames.