• 수산경영론집
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• 제23권2호
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• pp.53-67
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• 1992

It has been recognized, virtually from the time of its inception, that fisheries economics, like other aspects of resource economics, should ideally be cast in capital-theoretic terms. The fish population or biomass can be viewed as a capital stock in that, like conventional or man-made capital, it is capable of yielding a sustainable consumption flow through time. This study is to introduce the optimal control theory which was extended from the theory of calculus of variations into the study of former static theory of fisheries economics started by Gordon (1954). The optimal control theory eliminated the inadequacies of the classical techniques to a large extent. From this point of view, this study, on the base of Schaefer model, summerizes most of major results achieved so far, but does so in a manner such that the links with capital theory are made transparent. This study explores two sets of problems. The first concerns the optimal approach to the equilibrium stock, i.e. the optimal investment policy. The second set of problems arises from the relaxation of the highly restrictive assumption of autonomy (i.e. the assumption that the parameters are independent of time), then concludes the relaxation of linearity assumption together with the complexities caused by that.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제10권2호
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• pp.41-47
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• 2006

The Renewal process and the Non-homogeneous Poisson process (NHPP) process are probably the most popular models for describing the failure pattern of repairable systems. But both these models are based on too restrictive assumptions on the effect of the repair action. For these reasons, several authors have recently proposed point process models which incorporate both renewal type behavior and time trend. One of these models is the Modulated Power Law Process (MPLP). The Modulated Power Law Process is a suitable model for describing the failure pattern of repairable systems when both renewal-type behavior and time trend are present. In this paper we propose Bayes estimation of the next failure time after the system has experienced some failures, that is, Mean Time Between Failure for the MPLP model. Numerical examples illustrate the estimation procedure.

• Mycobiology
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• 제38권1호
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• pp.70-73
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• 2010

Temperature-sensitive yeast mutants were used to screen for cell cycle-related genes from Pleurotus eryngii genomic DNA. A mushroom genomic DNA library was established and each gene was screened for the ability to rescue seven Saccharomyces cerevisiae temperature-sensitive strains. Hundreds of yeast transformants were selected at restrictive temperatures over $30^{\circ}C$. Plasmids from the transformants that survived were isolated and transformed back into their host strains. The temperature sensitivity of the resulting transformants was tested from $30^{\circ}C$ to $37^{\circ}C$. Ten DNA fragments from P. eryngii were able to rescue yeast temperature-sensitive strains, and their DNA sequences were determined.

• 한국대기환경학회지
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• 제15권4호
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• pp.457-461
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• 1999

Recently, increasing usage of diesel vehicle, many countries try to reduce the pollutant materials by emission regulation standard. Particularly, in our country, the supplement ratio of diesel vehicle is high, and air pollution by particulate matter(PM) is very serious. So, in theoretical study wer analyzed the formation principle of gaseous emission and PM, the characteristics of CVS-75 mode. In experimental study, we tested exhaust gas reduction of emission and PM, the characteristics of CVS-75 mode. In experimental study, we tested exhaust gas reduction of disel oxidation catalyst(DOC) by CVS-75 mode in light duty diesel vehicle. In case of an automobiletest with the 2,956cc diesel engine which DOC was equipped, CVS-75 mode which is similar to driving conditions on the road was chosen as the restrictive mode of light duty diesel automobile in our country. According to the Pt, the reduction rate of exhaust emission was estimated with using 0.1% high sulfur fuel and 0.05% low sulfur fuel.

• Journal of Information Technology Applications and Management
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• 제11권4호
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• pp.95-102
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• 2004

This paper proposes a method of segmenting compound nouns which include unregistered nouns into a correct combination of unit nouns using characteristics of person's names, loanwords, and location names. Korean person's name is generally composed of 3 syllables, only relatively small number of syllables is used as last names, and the second and the third syllables combination is somewhat restrictive. Also many person's names appear with clue words in compound nouns. Most loanwords have one or more syllables which cannot appear in Korean words, or have sequences of syllables different from usual Korean words. Location names are generally used with clue words designating districts in compound nouns. Use of above characteristics to analyze compound nouns not only makes segmentation more accurate, helps natural language systems use semantic categories of those unregistered nouns. Experimental results show that the precision of our method is approximately 98% on average. The precision of human names and loanwords recognition is about 94% and about 92% respectively.

• Journal of applied mathematics & informatics
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• 제33권5_6호
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• pp.607-625
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• 2015

Recently, Wang et al. [Computers and Mathematics with Ap-plications 57 (2009) 1232-1248.] and Wang and Watada [Information Sci-ences 179 (2009) 4057-4069.] studied the renewal process and renewal reward process with fuzzy random inter-arrival times and rewards under the T-independence associated with any continuous Archimedean t-norm. But, their main results do not cover the classical theory of the random elementary renewal theorem and random renewal reward theorem when fuzzy random variables degenerate to random variables, and some given assumptions relate to the membership function of the fuzzy variable and the Archimedean t-norm of the results are restrictive. This paper improves the results of Wang and Watada and Wang et al. from a mathematical per-spective. We release some assumptions of the results of Wang and Watada and Wang et al. and completely generalize the classical stochastic renewal theorem and renewal rewards theorem.

• 한국자동차공학회논문집
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• 제9권5호
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• pp.1-8
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• 2001

It is a present situation that the control on automobile emission is getting more restrictive and also the regulations for emission are changing greatly up to level of those advanced foreign countries. Specially, it has been many years that exhaust gases from gasoline automobile rather than from diesel is the major object concerned by Korea and other countries, and it is strongly required on the reduction techniques on harmful NOx and PM among those compositions. Thus, this research focused on the Exhaust Gas Recirculation (EGR) and the target for this research is heavy-duty turbo-diesel engine with Cooled EGR. Furthermore, this research has been made efforts to accomplish the regulation on emission for heavy duty diesel engine.

• 한국자동차공학회논문집
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• 제10권1호
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• pp.93-98
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• 2002

It is a present situation that the control on automobile emission is getting more restrictive and also the regulations for emission are changing greatly up to level of those advanced foreign countries. Specially, it has been many years that exhaust gases from gasoline automobile rather than from diesel is the major object concerned by Korea and other countries, and it is strongly required on the reduction techniques on harmful NOx and PM among those compositions. Thus, this research focused on the Exhaust Gas Recirculation (EGR) and the target fur this research is heavy-duty turbo-diesel engine with EGR, and conducted with numerical simulation to get engine performance and the characteristics of emission. Furthermore. the results obtained under different conditions such as rpm, power, EGR rate are compared and investigated with the numerical simulation using KIVA-3.

• Journal of Chest Surgery
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• 제24권11호
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• pp.1149-1153
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• 1991

A modified procedure for the operative management of the corrected transposition of the great arteries with ventricular septal defect and pulmonary stenosis or atresia was performed in 4 patients. (age ; 18 months-9 years). The operation consists of a venous switch procedure (Senning), intraventricular baffling directing the blood flow from the morphologic left ventricle into the aorta via ventricular septal defect through the right ventriculotomy, and insertion of valved conduit between the morphologic right ventricle and the pulmonary artery. All the four patients had large non-restrictive ventriular septal defects and no evidence of significant mitral valve regurgitation. Both ventricles were well-developed. Three cases had pulmonary atresia, and the remainder had severe subpulmonic stenosis. Postperatively, all patients showed no findings of systemic or pulmonary venous obstruction withnormal sinus rhythm. One patient died of sepsis due to infection by Methicillin-resistant S. aureus on the thirteenth postoperative day. Follow-up is done on the survivors, and all of them are dong well with regular sinus rhythm, with their functional class I or II at 2 to 8 months after the operation.

• 논리연구
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• 제15권3호
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• pp.323-347
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• 2012

최근 이병덕 교수의 논란 없는 원리(Uncontested Principle)의 거부를 둘러싼 논의가 송하석, 최원배 등을 중심으로 이루어졌다. 필자는 이들 논의가 충분하지 않다고 생각한다. 그 이유는 이들이 논란 없는 원리가 연역에 관한 한 정당하다고 생각하지만 이들의 논증만으로는 그렇게 판단하기 어려운 점이 있기 때문이다. 필자는 이 점을 먼저 이 글에서 밝히고 그 한계를 지적한다. 다음으로 대안 논리(alternative logic)의 관점에서 볼 때 논란 없는 원리는 그 자체로 정당화되기 어렵고 연역적으로 정당화되기 위해서는 실제로 여러 가지 제약조건이 필요함을 보인다. 즉 특정 조건이나 제약 하에서만 연역적으로 정당화될 수 있음을 보인다.