• 음성과학
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• 제8권2호
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• pp.107-117
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• 2001

The purpose of this study is to revisit the property of tapping, based on the data from Yonbyon Korean. Taps have been described as short segments derived from corresponding stops or trills. It is also widely assumed that tapping occurs due to lenition to minimize articulatory effort. However, Yonbyon Korean data show that taps can occur in strong as well as weak positions The results of the acoustic experiments conducted in this study show that in syllable-onset position, obstruent taps consistently appear from the underlying laterals, while in intervocalic position, sonorant taps similar to American English taps occur. The results of this study provide evidence against the uniform account of tapping as the result of lenition.

• Journal of Plant Biology
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• 제38권3호
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• pp.297-303
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• 1995

Four species of Symphyocladia growing along the coast of Korea were investigated in taxonomic point of view. Characters available for identification of the species were; difference in gross morphology, degree of cortication in vegetative axis, presence or absence of vegetative trichoblasts, and developmental pattern of stichidia. Vegetative structure and reproductive organs in developmental anatomy were similar among species. Branching pattern and occurrence of vegetative trichoblasts adopted for systematic criteria between Pterosiphonieae and Polysiphonieae, and between Symphyocladia and Pterosiphonia were no more confidential. The degree of congenital fusion of laterals with the parent axes was considered as only main character to distinguish Symphyocladia from Pterosiphonia.

• Journal of Chest Surgery
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• 제33권10호
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• pp.806-811
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• 2000

Background : The authors have modified the method of Ravitch technique. Material and Method ; This technique was applied to 6 patients out of 18 patients who underwent corrective surgery from May 1987 to July 1999. The technique is quite different from that of Ravitch. We did not divide the intercostal muscle bundles from the laterals of sternum and the Akin's struts were placed retrosternally crossing the chest horizontally to prevent flail motion during immediate post-operative period and retraction of the sternum afterwards. Anterior sternal osteotomy instead of the posterior one was performed for the latest 3 cases which made operative procedure more simple and easy. The struts were removed one year later. Result : Compared to the hospital stay of the patients who received standard Ravitch method that of the six cases who received our modification was definitely shortened from 13.1 days to 8.3 days(p<0.0000). Flail motion was not noted in any patient and chest wall stability was obtained more easily with this technique. Conclusion : Our modification is recommendable for correction of funnel chest in regards to shorter operation time better chest wall stability shorter hospital stay and less complication.

• 대한전기학회논문지:전력기술부문A
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• 제53권12호
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• pp.670-677
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• 2004

The Conventional approach for estimating the locations of transmission line shunt faults has been to measure the apparent impedance to the fault from a line terminal and to convert the reactive component of the impedance to line length. But, these methods do not adequately address the problems associated with the fault location on distribution systems. This thesis presents a technique that estimates the location of shunt fault on a radial distribution system that has several single and multiphase laterals. Tapped loads and non-homogenity of the distribution system are take into account. The developed technique, which can handle shunt faults was tested to evaluate its suitability. Results from computer simulation of faults on a model of a 25KV distribution lines like real system are presented. The results approved that the proposed technique works well for estimating the locations of the distribution line shunt faults.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전력기술부문
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• pp.121-123
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• 2001

This paper presents a fault location algorithm using iterative method at unbalance condition for distribution feeder systems. Distribution feeders include single phase and three phase laterals. The proposed algorithm achieves a high accuracy by continuously updating voltage and current phasor using the phase components and admittance load model.

• KIEE International Transactions on Power Engineering
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• 제3A권2호
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• pp.79-84
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• 2003

Unbalanced systems, such as distribution systems, have difficulties in fault locations due to single-phase laterals and loads. This paper proposes new fault locations developed by the direct three-phase circuit analysis algorithms using matrix inverse lemma for the line-to-ground fault case and the line-to-line fault case in unbalanced systems. The fault location for balanced systems has been studied using the current distribution factor, by a conventional symmetrical transformation, but that for unbalanced systems has not been investigated due to their high complexity. The proposed algorithms overcome the limit of the conventional algorithm using the conventional symmetrical transformation, which requires the balanced system and are applicable to any power system but are particularly useful for unbalanced distribution systems. Their effectiveness has been proven through many EMTP simulations.

• 한국육종학회지
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• 제40권4호
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• pp.371-376
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• 2008

For the purpose of breeding a high-yield superior variety of Korean raisin tree (Hovenia dulcis var. koreana Nakai), whose value as an edible and medicinal resource is increasing, tree candidates for superior individuals were selected from its 11 habitats in Korea from 1996 to 1998. A clone bank preserve was created in 1998 with 70 clones proliferated by grafting; the fruition traits (e.g., the number of fructified laterals, the average number of bunches per fructified lateral, the average number of bunches per fruiting lateral, the fruitpetiole weight per individual, and the yield per individual) of 47 clones that had bloomed and borne fruit were investigated and analyzed in 2002; five upper-ranking clones whose yield per individual exhibited a 261% improvement against the total average were picked in 2005; and three clones, including 'Poong-Sung 1', that showed a difference in their fruit petiole ripening stage, were finally selected in 2007 as high-yield new cultivars of Korean raisin tree.

• 한국토양비료학회지
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• 제16권3호
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• pp.280-285
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• 1983

Subterraneum 클로바의 생장(生長)에 미치는 pH와 칼슘의 영향(影響) 및 품종간(品種間) 반회차이(反灰差異)를 수경재배(水耕栽培) 실험(實驗)으로 조사(調査)하였다. 1. 산성(酸性)(pH 4.5이하(以下))에서 발아율(發芽率)을 제외(除外)한 조사조(調査調)된 모든 생장요인(生長要因)이 저하(低下)되었다. 2. 산성(酸性)에 의한 생장장해(生長障害)는 높은 농도(濃度)의 칼슘(3.0mM)처리(處理)로 감소(減少)되었다. 3. 산성(酸性)에 대한 반응(反應)에는 품종간(品種間)에 차이(差異)가 있어 Mt. Barker는 조사(調査)된 세 품종중(品種中) 가장 높은 발아율(發芽率) 및 가장 긴 유근신장(幼根伸長)을 보였으나, 지상부(地上部) 및 근건물중(根乾物重), 근장(根長) 및 측근(側根)의 수(數)에 있어서는 Tallarook가 가장 높은 값을 나타내었다.

• 전기학회논문지
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• 제62권9호
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• pp.1199-1208
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• 2013

In recent years, the development of application programs for distribution system analysis and control has been essential part for distribution management system (DMS). In this paper, we propose the common database for application programs of distribution management system. The proposed database model has several characteristics as followings. First, the proposed database model is designed for the common use of almost the whole distribution application software. The static equipment model and dynamic type tables are mixed and the parallel table structure is applied. Second, the linked list structure of database are used for the fast processing of applications. The database model includes the hierarchy and non-hierarchy distribution system structure. Third, the reduction method of distribution database is applied. For this, we present the network reduction rules. The basic concept of reduction rules are the electrical unification of successive line section which has not lateral branches and the removal of simple lateral branches which has no devices and other laterals. Proposed database model is tested for the Jeju system of Korea Electric Power Corporation (KEPCO). Through the test, we verified that the proposed database structure can be effectively used to accomplish the distribution system operation.

• 대한치과교정학회지
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• 제19권2호
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• pp.145-153
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• 1989

The causes of the missing teeth are classified as congenital missing, trauma and extraction due to dental caries, variable problems are occured clinically by the missing teeth. The missing of the upper incisors especially would assume a serious aspect, and could be treated by three methods of orthodontic treatment, prosthodontic treatment and autotransplantation of the premolar teeth. The patient of this report had the skeletal class II malocclusion with the left upper central incisor missing, and have been treated with the fixed appliance after extraction of the right upper central incisor and both lower second premolars. The results were obtained as follows: 1. Treatment was done for 1 year 6 months. 2. Normal overbite and overjet were achieved. 3. Cuspal interdigitation was obtained normally. 4. Space problem was resolved with resin restoration of the upper lateral incisors. 5. The upper canines were used as the upper laterals after cuspal contouring. 6. Retention would be required with adequate retainers for a long time to prevent relapsing after treatment.