• Journal of Microbiology
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• 제33권3호
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• pp.208-214
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• 1995

The effects of various 2, 4-D-degradative plasmids on the axenic growth patterns, the degradation phenotypes, and the competitiveness of different host bacteria were evaluated in liquid cultures; the organisms and plasmids used were Alcaligenes eutrophus JMP134/pJP4, Alcaligenes paradoxus/p2811, Pseudomonas pickettii/p712, pJP4, and p712 or p 2811 exhibited very different restriction fragment profiles in restriction endonuclease digests. These plasmids were transferred to the recipients (P. cepacia and Alcaligenes JMP228) at relatively high frequencies ranging from 8.9 $\times$ 10$^3$ to 1.6 $\times$ 10$^5$ per donar cell. In the axenic liquid cultures the fast-growing strains, such as P. pseudomallei/p745 and P. cepacia/pJP4, exhibited short lag periods, high specific growth rates, and high relative fitness coefficients, while the slow-growing strains, such as P. pickettii/p712 and A. paradoxus/p2811, had long lag periods, low specific growth rates, and low relative fitness coefficients. Depending on the type of plasmid containing the genes for the 2, 4-D pathway, some transconjugants exhibited intermediate grwoth patterns between the fast-growing strains and the slow-growing strains. The plasmid and plasmid-host interactions determined specific growth rate and lag time, respectively, which were shown to be principal determinants of competitiveness among the strains, but relative fitness coefficient derived from the axenic culture was not always predictive for the mixed culture condition.

• Computers and Concrete
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• 제10권6호
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• pp.587-607
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• 2012

The purpose of this research is to propose a design technique of concrete mix proportions satisfying service life through genetic algorithm (GA) and neural network (NN). For this, thirty mix proportions and the related diffusion coefficients in high performance concrete are analyzed and fitness function for diffusion coefficient is obtained considering mix components like w/b (water to binder ratio), cement content, mineral admixture (slag, flay ash and silica fume) content, sand and coarse aggregate content. Through averaging the results of 10 times GA simulations, relative errors to the previous data decrease lower than 5.0% and the simulated mix proportions are verified with the experimental results. Assuming the durability design parameters, intended diffusion coefficient for intended service life is derived and mix proportions satisfying the service life are obtained. Among the mix proportions, the most optimized case which satisfies required concrete strength and the lowest cost is selected through GA algorithm. The proposed technique would be improved with the enhancement of comprehensive data set including wider the range of diffusion coefficients.

• 대한토목학회논문집
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• 제30권5A호
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• pp.433-442
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• 2010

콘크리트의 염화물 확산계수의 제어는 염해에 노출된 콘크리트 구조물의 내구수명 확보에 필수적이며, 이를 위해 많은 연구가 진행되어 왔다. 본 연구는 목표 내구수명을 만족하는 목표확산계수를 도출하고 유전자 알고리즘을 통하여, 최적배합을 도출하는데 있다. 이를 위하여, 동일한 골재 및 혼화재를 사용한 30개의 배합과 그에 따른 염화물 확산계수를 분석하였으며, 27개를 대상으로 확산계수 예측식을 도출하였다. 확산계수 예측식의 변수로는 물-결합재비, 단위 혼화재량(슬래그, 플라이 애쉬, 실리카퓸), 단위 시멘트량, 단위 잔골재 및 굵은 골재량을 포함하도록 하였으며 나머지 3개의 배합에 대하여 검증을 수행하였다. 최적 함수식은 27개의 배합에 대하여 평균 18.7%의 오차와 16.0%의 변동계수를 보이고 있었다. 주어진 3개의 확산계수에 대하여, 유전자 알고리즘을 통하여 도출된 배합은 0.3%~12.2%의 오차범위를 가지며 각각의 배합인자를 도출하였다. 최종적으로 서로 다른 내구성 설계변수(목표내구수명, 피복두께, 표면염화물량, 혼화재량)와 노출환경(온도 및 습도)을 가정하여 목표 확산계수를 도출하였으며, 이에 만족하는 최적화된 콘크리트 배합을 제안하였다. 본 연구에서는 유전자 알고리즘을 이용하여, 내구성 콘크리트 배합도출에 대한 적용성을 평가하였으며, 제안된 기법은 다양한 확산계수의 범위를 가지는 광범위한 자료구축을 통하여 개선될 것이다.

• 경영과정보연구
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• 제17권
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• pp.161-189
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• 2005

As the importance of intellectual assets has been brought into relief, this study aims at positively verifying where the intellectual workers' overall level of their knowledge conversion preference and their job character has reached, and how much the knowledge conversion preference, the job character and the fitness of both factors affects the job effectiveness respectively. For this purpose 3 types of research hypotheses were set up and the result of the verification of the hypotheses is summarized as follows: First, the verification of the relation between the knowledge conversion preference and the job effectiveness revealed that the workers who have the higher synthetic ability in knowledge conversion preference show the higher job satisfaction and job product. Secondly, the verification of the relation between the MPS representing the job character by measured index and the job satisfaction revealed that the absolute value of relative coefficient between the 4 factors excluding the public welfare factor and the MPS is 4, interpreted as medium correlation. Thirdly, the analysis on the degree of relation between the job product measured by the quality of job result and the input effort and the MPS showed that the absolute value of person relative coefficient is 5, interpreted not only as medium correlation but also very meaningful. Accordingly, the main purpose of this study was to give a guideline which can be utilized as an indicator for educating, training and placing the workers. As results, the main effect that the variable of knowledge conversion preference and job character chosen as the independent variable influences on the dependent variable of job satisfaction and job product is very meaningful except the public welfare factor.

• 콘크리트학회논문집
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• 제22권3호
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• pp.335-343
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• 2010

콘크리트 내부의 철근부식은 구조물의 안전성에 큰 영향을 주므로, 목표 내구수명동안 구 조물의 성능을 확보하려는 연구가 활발하게 진행되고 있다. 이 연구는 대도시나 지하구조물에서 중요하게 평가되는 탄산화에 대하여, 유전자 알고리즘을 적용한 콘크리트 배합기법에 대한 연구이다. 이를 위해, 배합인자에 따른 이산화탄소 확산계수를 문헌조사를 통하여 분석하였으며, 습도를 고려한 최적 함수식을 회귀분석을 통하여 도출하였다. 최적 함수식은 12개의 실험자료에 대하여, 물-시멘트비, 단위 시멘트량, 잔골재율, 단위 굵은골재량, 그리고 상대습도를 포함하도록 고려하였으며, 유전자 알고리즘을 통하여, 주어진 이산화탄소 확산계수에 대한 콘크리트 배합을 도출하였다. 3개의 배합에 대하여 검증한 결과, 10% 미만의 상대오차를 보이며 주어진 배합을 잘 추정하였다. 최종적으로 서로 다른 환경과 설계 제원을 가지는 콘크리트 구조물을 가정하여, 목표 확산계수와 단위 시멘트량을 계산하였으며, 이를 이용하여 배합을 추정하였다. 제안된 기법은 주어진 확산계수와 배합을 잘 추정하였으며, 다양한 배합인자 및 혼화재료가 고려된 실험 자료를 이용한다면 더욱 합리적인 배합 기법으로 발전할 것이다.

• 한국환경보건학회지
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• 제23권4호
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• pp.73-81
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• 1997

Diphtheria was the world-spread, respiratory infectious disease in the past. But after developing the diphtheria toxoid, diphtheria vaccine, composed of diphtheria toxoid, is generalized, so prevalence of diphtheria is sharply dropped. But diphtheria is come back in NIS(New Independent States) in 1990s. It is believed that recurrence of diphtheria is mainly due to shortage of protective diphtheria antibody titer in adults. And it is related to 70% prevalence in adults, not in children. Considering this changing environment, this study was designed to research the diphtheria antibody titer of whole population and existence of titer difference by sex. Also it was studied whether ELISA has fitness as determination method of diphtheria antibody titer compared with neutralization method on microcell culture. This study was done to 277 samples of three hospitals in Seoul area, and sera was tested by neutralization method on microcell culture and ELISA method. The results of this study were as follows 1) Of this studied population, 31.05% had an antibody titer below the protective level (<0.01 IU/ml), 40.79% had a titer of a relative degree of protection (0.01-0.09 IU/ml) and 28.16% had a reliable degree of protection ($\geq$0.1 IU/ml). Therefore, 68.95% had a basic protective antibody titer level. 2) 20-40 age group showed the lowest diphtheria antibody titer among the studied population. 3) GMT of diphtheria antibody titer was the highest in the children. But, after child period, GMT was fallen. Standard deviation value was the lowest in older group. 4) Protective level of diphtheria antibody titer of male was slightly higher than female (70.94% vs 66.66%). But this difference was not statistically significant. 5) Diphtheria antibody titer by ELISA method was wholly higher than by neutralization method on microcell culture. Compared the two results by ELISA and neutralization, the regression coefficient was 0.38. And in titer, which was obtained by ELISA method, false-positive results was abundant.

• Journal of the Korean Data and Information Science Society
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• 제27권2호
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• pp.395-407
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• 2016

본 연구는 G-Theory를 적용하여 태권도 품새 평가항목에 대한 채점자 간 평가점수의 신뢰도를 추정하기 위해 G-연구로 경기일 수, 채점자 수를 다중오차원으로 선정하고 이들 변인간의 상호작용으로 인한 오차변량의 상대적 크기에 의해 오차원을 분석하고, G-연구의 결과를 토대로 D-연구를 수행하여 최적의 측정조건을 결정하는 데 목적이 있다. 결과를 요약하면 다음과 같다. G-Theory를 적용하여 태권도 품새 평가항목 중 정확성에 대해 분산성분 추정치를 추정한 결과, 오차의 영향력은 채점자국면에서 가장 크게 나타났으며, 각 설계에 따른 상호효과 (피험자 내), 피험자 간 순서였으며, 표현성 평가항목에 대한 분산성분 추정치 오차의 영향력은 상호효과 (피험자 내)국면에서 가장 크게 나타났으며, 각 설계에 따른 피험자 간, 채점자 국면 순으로 나타났다. 마지막으로 D-연구를 통하여 일반화가능도계수를 추정한 결과, 채점자 수에 따른 최적수준의 측정조건은 정확성 평가항목에서 8명의 채점자일 때 안정적인 신뢰도를 얻을 수 있으며, 표현성 평가항목에서는 7명의 채점자일 때 안정적인 신뢰도를 얻었다.