• 대한토목학회논문집
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• 제13권1호
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• pp.97-103
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• 1993

두 개의 서로 다른 수문지질학적 성질을 갖는 다공성 매질이 대수층을 이룰 때, 수두분포를 적분방정식을 이용한 준해석적인 방법으로 구하는 방법을 연구하였다. 하단(下端)에서 지하수위(地下水位)의 위치가 알려져 있고, 하단(下端)에서의 경계조건이 일정수도 혹은 일정 유동량으로 주어질 때의 1차원 해석 알고리즘을 개발하고, 충적층(沖積層)(alluvium) 위에 석탄재(fly ash)를 매립하는 처분장의 경우에 적용하였다. 그 결과 얻어진 수두분포는 경계면 바로 윗부분에서 매우 큰 압력경사를 나타내었고, 이것이 수치해석을 어렵게 만드는 요인임을 발견하였다. 해석적으로 얻은 압력경사는 수치해석 수행시 격자(格子)의 배열을 어떻게 할 것인지에 대한 대안을 제시하였고, 그에 따른 수치해석 결과는 해석치와 근사함을 보였다.

• 한국초등과학교육학회지:초등과학교육
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• 제34권1호
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• pp.46-57
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• 2015

The purpose of this study was to analyze the writing styles and features of science writing by using science notebook for elementary school science gifted. The subject of this study was 37 sixth grade elementary school science gifted in P city. The preliminary 1 hour instruction was conducted to explain the usage of science notebook. The summarized activity using science notebook was conducted for 20 minutes following 4 hour lesson. These activities were performed for 8 times. As the result of this study, in The content which is learned today (main learning content)' which is one of components of science note, the writing appears the most frequently in external expression types and features of scientific writing, followed by writing+drawing, drawing, cartoon, writing+cartoon, mind map, table. Science writing which uses inductive thinking appears the most frequently in internal expression types and features of scientific writing, followed by deductive thinking, creative thinking. Among the components of science note, 'thinking and feeling', 'question,' 'one's own thinking of question' which are the components of science note promote the reflective thinking of elementary school student gifted for science.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2003년도 제2차 연례학술대회 발표논문집
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• pp.133-138
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• 2003

The prediction of protein secondary structure has been an important bioinformatics tool that is an essential component of the template-based protein tertiary structure prediction process. It has been known that the predicted secondary structure information improves both the fold recognition performance and the alignment accuracy. In this paper, we describe several novel ideas that may improve the prediction accuracy. The main idea is motivated by an observation that the protein's structural information, especially when it is combined with the evolutionary information, significantly improves the accuracy of the predicted tertiary structure. From the non-redundant set of protein structures, we derive the 'potential' parameters for the protein secondary structure prediction that contains the structural information of proteins, by following the procedure similar to the way to derive the directional information table of GOR method. Those potential parameters are combined with the frequency matrices obtained by running PSI-BLAST to construct the feature vectors that are used to train the support vector machines (SVM) to build the secondary structure classifiers. Moreover, the problem of huge model file size, which is one of the known shortcomings of SVM, is partially overcome by reducing the size of training data by filtering out the redundancy not only at the protein level but also at the feature vector level. A preliminary result measured by the average three-state prediction accuracy is encouraging.

• Coupled systems mechanics
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• 제1권4호
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• pp.311-324
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• 2012

Previous investigations have demonstrated that strong earthquakes can cause severe damage or collapse to storage tanks. Theoretical studies by other researchers have shown that allowing the tank to uplift generally reduces the base shear and the base moment. This paper provides the necessary experimental confirmation of some of the numerical finding by other researchers. This paper reports on a series of experiments of a model tank containing water using a shake table. A comparison of the seismic behaviour of a fixed base system (tank with anchorage) and a system free to uplift (tank without anchorage) is considered. The six ground motions are scaled to the design spectrum provided by New Zealand Standard 1170.5 (2004) and a range of aspect ratios (height/radius) is considered. Measurements were made of the impulsive acceleration, the horizontal displacement of the top of the tank and uplift of the base plate. A preliminary comparison between the experimental results and the recommendations provided by the liquid storage tank design recommendations of the New Zealand Society for Earthquake Engineering is included. The measurement of anchorage forces required to avoid uplift under varying conditions will be discussed.

• 한국강구조학회 논문집
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• 제15권4호통권65호
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• pp.413-422
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• 2003

구조 설계를 위해 초기 부재를 가정할 때나 건축 실무에서 개산 견적을 계산할 때 기술자의 직관이나 비슷한 조건의 기존 설계 평균값을 사용하고 있으나 설계 조건은 모두 다르기 때문에 큰 오차가 발생할 수밖에 없다. 이러한 문제점을 해결하기 위해서 확률론적인 절차가 내재되어 있어 불확실성을 다룰 수 있는 인공 신경 회로망의 이용하여 와렌 트러스를 설계하므로써 적용성을 평가하였다. 제안된 신경망 설계변수값와 구조설계 단계에 따라 다양한 와렌 트러스를 설계하여 MIDAS 프로그램 설계결과의 10% 오차 이내로 근사 설계를 하므로써 모델의 타당성을 검증하였다. 제안된 모델은 약간의 오차를 포함하지만 적은 시간과 노력으로 신뢰할 수 있는 설계 결과를 얻을 수 있으며, 부재 테이블을 사용하는 비선형 관계의 구조설계에도 적용 가능한 특성을 가지고 있다.

• 대한조선학회지
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• 제4권1호
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• pp.59-65
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• 1967

Since the screw propellers were adopted as ship propulsion devices, the replacement of propeller shaft due to damage was mostly of fatigue failure due to the alternative stresses [1],[2]. To prevent such a failure, hence, it is suggested that careful attention should be paid to account of the alternative stresses on the design stage of the propeller shafts. In connection with this fact the Ship Classification Societies' Rules are regarded simply as guidance for preliminary determination of the shaft diameter. In this paper, limiting the topic to the small and medium-sized motor ships, an evaluation of the Rules formulae to a theoretical based on Soderberg's correlation [5] between the factor of safety and the resultant stresses obtained by application of the maximum shear theory is done. For this purpose eleven (11) ships built recently in Korea were taken as a species(refer to table 2. in text). In the end the following conclusions are made: (1) In general the Rules formulae give considerably larger size of the propeller shaft diameter than that derived from theoretical calculation, that is, about 7% more in AB and BV Rules, and about 20% more in LR and KR-NK Rules. (2) LR Rule gives the largest size of all, and AB Rule is mostly closed value to the theoretical. (3) The formular of the AB Rule is considered to be of the simplest in utilization and of the reasonable.

• Journal of Photoscience
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• 제3권2호
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• pp.91-93
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• 1996

In connection with our interest on the photochemical properties of heteroaryl halides, which are currently the subject of heterocyclic ring formation and haloarene degradation, we have studied the photochemistry of the haloarene linked to N-heteroarene compounds. Imidazo[5,1-a]isoindole was synthesized from N-(ochlorobenzyl)imidazole or N-(o-bromobenzyl) imidazole in acidic aqueous solution or acetonitrile via the intramolgcular photocyclization (Table 1). This type of reaction provides the synthetic methods for 5- and 6-membered polyheteroatomic heterocyclic ring compounds. However, the reaction mechanism for the intramolecular photocyclization of haloarene tethered heteroarenes has not yet been established. Grimshaw et al. suggested a mechanism for homolyric carbonhalogen bond fission assisted by radical complexation to explain their results in the photocyclization of 5-(2-chlorophenyl)-1,3-diphenylpyrazole. They also reported the detection of acyclohexadienyl intermediate involved in the above reaction. Park et al. reported several transient 'intermediates involved in the laser flash photolysis of N-(o-halobenzyl) pyridinium and N-benzyl-2-halopyridinium salts. Thus we performed the laser flash photolysis study on the photocyclization reaction of N-(o-chlorobenzyl) imidazole to identify the intermediate species involved in the reaction. Here, we report on the preliminary results in the photocyclization reaction of N-(o-halobenzyl)imidazole through the detection of reaction intermediates.

• Human Ecology Research
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• 제54권6호
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• pp.631-642
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• 2016

This study analyzed of the themes (wounding and healing); concerning the Sandplay therapy process applied to children with emotional instability and attention deficit problems. The subjects of the study were 30 elementary school children who agreed to a personal-interview with the author. They all were families of receiving basic livelihood welfare living in the same county. After the preliminary analysis, the main study data collected from subjects was analyzed by variance (t-test), frequency analysis, and correlation analysis using the standard table modified in accordance with Mitchell's classification system. Particular attention was made in the analyses of the characteristics of the subjects as members of low-income families. As the Sandplay therapy proceeded, it became evident that the wounding area showed a low frequency while the healing area featured a high frequency, and confirmed (as in previous studies) that the Sandplay therapy would be effective for children with emotional instability as well as for those with attention deficit problems. The analysis of difference between the types of children with both problems revealed that Sandplay therapy was more effective for children with emotional instability than for those with attention deficit problems. The analysis also revealed that Sandplay therapy was more effective for girls than for boys.

• 복식문화연구
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• 제26권2호
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• pp.217-232
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• 2018

As the types of wedding ceremonies become diversified, and consumers' needs become more selective, greater importance is given to wedding planners' roles in the wedding industry, and consumers require differentiated types of wedding service. As a preliminary qualitative study in this field, an ethnographic study was conducted to identify factors valued by consumers when selecting a wedding planner in the wedding planner market, which has rapidly grown in recent years. An in-depth interview was performed with eight participants in terms of wedding planner utilization type and consumers' understanding of wedding preparation with a wedding planner. The collected data were analyzed through taxonomy, component analysis and decision table analysis; for validation, professional wedding planners were asked to review the items valued by consumers in selecting a wedding planner. Four factors - expense characteristic, wedding planners, wedding consulting companies, and customer characteristics - were identified, along with eight sub-factors (capability, service attitude, technical communication, personal factors, wedding planner encounter paths, spouse's satisfaction status, and companies). Out of these, price (within budget), wedding planners' capability, wedding planners' service attitude are expected to be meaningful in further research because they were found to be attributes commonly valued by every respondent. This study is significant in that it has made a new approach to understanding wedding planner selection attributes through ethnographic research and identified new wedding planner selection attributes.

• 자원리싸이클링
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• 제16권6호
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• pp.34-38
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• 2007

폐콘덴서로부터 탄탈륨 음극을 회수하기 위하여 물리적 선별과, 염소가스와 사염화탄소를 이용한 기초 염화반응에 관한 연구를 수행하였다. Stamp mill을 이용한 파쇄, 요동테이블에서의 습식 비중선별 그리고 공기 분급을 통하여 탄탈륨 음극을 98% 회수할 수 있었다. 염소가스를 이용한 TGA분석에서 탄탈륨 음극의 최대 무게 감소는 60%였고, 사염화탄소에 의한 탄탈륨 음극의 염화반응은 탄탈륨 음극을 산화탄탈륨으로 변환한 후가 반응율이 높았다.