다기간효율적(多期間效率的) 신호균형모형(信號均衡模型)에 의한 배당(配當) 및 자금조달정책(資金調達政策)의 연구(硏究)

이건호,Lee, Geon-Ho 한국재무관리학회 1992 재무관리연구 Vol.9 No.1

본(本) 논문(論文)에서는 기업 내부자와 자본시장 간에 정보(情報)의 배분(配分)이 불균등할 경우 외부자금의 조달 및 주주에 대한 현금배당 등의 재무정책(財務政策)에 관한 장기계획의 수립에서 고려하여야 할 문제들을 2단계(2段階) 효율적신호(效率的信號) 균형(均衡)의 모형(模型)을 통하여 분석하였다. 본(本) 연구(硏究)에서는 단위 기간의 연결체인 장기모형을 동태적(動態的)으로 분석함으로써 각 단위 기간의 모형 구성이 기존의 연구들과 유사함에도 불구하고 기존의 정태적(靜態的) 분석(分析)들에서 밝혀지지 않았던 현상들까지 설명이 가능하였다. 기존의 연구들에서 밝혀진 배당(配當) 및 신주발행(新株發行)의 정보효과(情報效果)는 본 연구의 동태적 균형에서도 나타났으나, 일반적으로 정태적 모형들이 재무정책(財務政策)의 정보효과에 기인한 투자정책의 왜곡을 지나치게 과장하고 있음을 보였다. 또 기존의 연구들에서는 분석이 곤란하였던 배당 및 기업 내부자금의 장기적 균등화의 문제를 분석하여 적정 여유자금의 보유가 기업가치의 증대에 도움이 됨을 보였다.

냉난방기 에너지소비 저감을 위한 이중외피시스템의 이해

이건호,Lee, Geon-Ho 대한설비공학회 2006 설비저널 Vol.35 No.11

실리콘 웨이퍼 세정을 위한 오존의 거동에 관한 연구

이건호,김인정,배소익,Lee Gun-Ho,Kim In-Jung,Bae So-Ik 한국반도체디스플레이기술학회 2005 반도체디스플레이기술학회지 Vol.4 No.4

The behavior of ozone in $NH_4OH$ was investigated to evaluate the solution as a cleaning chemical of the silicon wafer. The solubility of ozone in DI(Deionized) water increased as the oxygen flow-rate decreased and ozone generator power increased. Ozone in DI water showed solubility of 100 ppm or higher at room temperature. Ozone concentration was stabilized at the range of ${\pm}2ppm$ by controlling oxygen flow rate and ozone generator power. On the contrary, the solubility of ozone in $NH_4OH$ was very low and strongly depended on the concentration of $NH_4OH$ and pH. The redox potential of ozone was saturated within 10 minutes in DI water and decreased rapidly with the addition of $NH_4OH$. The behavior of ozone in $NH_4OH$ is well explained by redox potential calculation.

폐패각-정유폐촉매-배연탈황석고를 사용한 Calcium Sulfoaluminate 클링커의 합성과 특성

이건호,송태웅,Lee, Keon-Ho,Song, Tae-Woong 한국세라믹학회 2005 한국세라믹학회지 Vol.42 No.7

For the raw materials of 3CaO$\cdot$3Al$_{2}$O$_{3}$ $\cdot$CaSO$_{4}$(CSA) clinker manufacturing, the applications of industrial wastes such as waste shell, spent oil-refining catalyst and desulfurized gypsum were examined. The c1inkerbility of the raw mix and the behaviour of formation of clinker minerals were studied and then some hydraulic properties of cements containing the clinker were also investigated. By virtue of the high reactivity of thermally decomposed raw materials, CSA clinkers were obtained at relatively low temperature of 1250$^{\circ}C$ and thus oil-refining catalysts were more desirable than aluminium hydroxide as an aluminous raw material. The expansive cement samples showed somewhat lower flow value than that of OPC, but their compressive strengths were developed earlier and higher than that of OPC due to formation of ettringite in the early hydration time, which indicated the possibility of practical use of low-cost CSA clinker using industrial wastes only.

사례기반추론과 규칙기반추론을 이용한 e-쇼핑몰의 상품추천 시스템

이건호,이동훈,Lee, Gun-Ho,Lee, Dong-Hun 한국정보처리학회 2004 정보처리학회논문지D Vol.11 No.5

e쇼핑몰 경영자들은 고객들의 다양한 제품 구매 욕구를 충족시키기 위한 효율적 시스템에 많은 관심을 가지고 있다. 인터넷 쇼핑몰 운영에 있어 고객들의 개인적 구매 특성 및 취향을 파악하여 고객들을 효과적으로 관리하는데 많은 어려움이 있다. 상품 추천의 과정이 기획된 소수의 특정 상품을 고객의 유형 및 특성들의 고려 없이 공급자 중심으로 이루어져 고객관리의 문제점으로 지적되고 있다. 본 연구에서는 고객위주의 추천을 위해 규칙기반추론(Rule-Based Reasoning, RBR)과 사례기반추론(Case-Based Reasoning, CBR)을 하여 고객의 취향 및 구매 특성에 따른 추천방법을 제시한다. 기존의 제품 판매정보와 고객정보를 이용해 생성한 규칙베이스와 사례베이스의 고객특성과 입력된 고객특성의 유사도를 평가해서 고객의 취향에 따라 추천하도록 한다. 생성된 규칙과 사례기반의 추론으로 기존의 정보를 효과적으로 사용하고 또한 고객 및 시장 상황의 변화를 인식하고 지속적인 학습을 수행하여 지능적 추천이 이루어진다. It is a major concern of e-shopping mall managers to satisfy a variety of customer's desire by recommending a proper product to the perspective purchaser. Customer information like customer's fondness, age, gender, etc. in shopping has not been used effectively for the customers or the suppliers. Conventionally, e-shopping mall managers have recommended specific items of products to their customers without considering thoroughly in a customer point of view. This study introduces the ways of a choosing and recommending of products using case-based reasoning and rule-based reasoning for customer themselves or others. A similarity measure between one member's idiosyncrasy and the other members' is developed based on the rule base and the case base. The case base is improved for the system intelligence by recognizing and learning the changes of customer's desire and shopping trend.

객체지향개발에서의 속성 클러스터링과 클래스 계층구조생성

이건호,Lee Gun Ho 한국정보처리학회 2004 정보처리학회논문지D Vol.11 No.7

객체지향 소프트웨어 개발 초기단계에서 클래스의 결정은 많은 객체와 관련된 속성들의 클러스터링을 하는 복잡한 문제이다. 클래스의 재사용을 위해 라이브러리에 클래스의 등록은 반복적인 시행착오에 의존하여왔다. 클래스를 등록하는 전통적인 방법과 모델링 혹은 설계단계에서 클래스와 그 계층구조의 정의를 위한 통합적인 방법에 대해 논의한다. 속성 클러스터링 문제를 위해 객체들의 속성 유사도에 근거하여 0-1 정수프로그램 위한 모형을 제시하고 또한 네트워크 기법을 이용한 클러스터링 알고리즘을 제안한다. 클래스 계층구조를 생성하기 위한 규칙을 제시하였으며 계층구조그래프 생성알고리즘을 제안한다. 본 연구결과를 이용하여 실제 현장의 문제를 사례로 제시한다. The clustering characteristics for a number of classes, and defining the inheritance relations between the classes is a difficult and complex problem in an early stage of object oriented software development. We discuss a traditional iterative approach for the reuse of the existing classes in a library and an integrated approach to creating a number of new classes presented in this study. This paper formulates a character-istic clustering problem for zero-one integer programming and presents a network solution method with illustrative examples and the basic rules to define the inheritance relations between the classes. The network solution method for a characteristic clustering problem is based on a distance parameter between every pair of objects with characteristics. We apply the approach to a real problem taken from industry.

불화나트륨 바니쉬와 요오드화 칼륨이 Silver Diamine Fluoride의 재광화 효과에 미치는 영향

이건호,안준용,김종수,한미란,이준행,신지선,Lee, Kunho,Ahn, Junyong,Kim, Jong Soo,Han, Miran,Lee, Joonhaeng,Shin Jisun 대한소아치과학회 2021 대한소아치과학회지 Vol.48 No.4

The purpose of this study was to compare the effect of sodium fluoride(NaF) varnish and potassium iodide(KI) on remineralization efficacy of silver diamine fluoride(SDF) by measuring microhardness and evaluating surface morphology by scanning electron microscope(SEM). Artificial caries lesions were induced on extracted primary molars and vickers microhardness was measured. Specimens were randomly separated into 4 groups for treatment. The specimens in group I were treated with SDF, group II with NaF varnish after SDF, group III with KI after SDF and group IV with distilled water. After 8 days of pH cycling, vickers microhardness was measured and difference before and after treatment was calculated. For SEM, 2 samples were evaluated respectively after enamel polishing, lesion formation and after pH cycling. Group III showed highest increase in microhardness. Group I showed higher increase in microhardness than Group II but without statistical difference. Group IV showed lowest increase in microhardness value among 4 groups. On SEM image, group I, II and III showed smoother and less irregular surface compared to group IV. Amorphous crystal pellicles were observed in group III. In conclusion, SDF, SDF and NaF, SDF and KI groups showed smoother surface and increase in microhardness suggesting the possibility that remineralization effect might take place in oral conditions. In addition, in limited conditions of this study, applying NaF varnish after SDF did not increase the remineralization efficacy of SDF while KI significantly increased the remineralization efficacy of SDF. However, additional study considering various conditions that might affect demineralization and remineralization in clinical situations need to be conducted.

폐암 방사선 치료 시 Hybrid-Volumetric Modulated Arc Therapy의 유용성 평가

이건호,강효석,최병준,박상준,정다이,이두상,안민우,전명수,Lee, Geon Ho,Kang, Hyo Seok,Choi, Byoung Joon,Park, Sang Jun,Jung, Da Ee,Lee, Du Sang,Ahn, Min Woo,Jeon, Myeong Soo 대한방사선치료학회 2017 대한방사선치료학회지 Vol.29 No.2

Objectives: In the Lung, the VMAT rotates continuously and examines radiation. That increases the low doses to normal lung. Due to that, the incidence of radiation pneumonia among radiation side effects may increase. The cause of radiation pneumonia is the lower dose area of the lungs. The H-VMAT was applied to patients who applied to reduce radiation in the lower doses of the lungs. We wanted to assess the usefulness of the H-VMAT by comparing the radiation doses to the low dose areas of the lungs and the normal organs. Materials and Methods: A total of 26 patients who applied for a H-VMAT procedure were applied to the patient. The prescription dose applied to total dose 44 Gy from 22 divisions. For each patient, a plan was implemented with Conventional RT, VMAT and H-VMAT. Conventional RT was carried out in four to five fields each, considering the size, location, shape, and location of the PTV. In the case of a VMAT plan, the two Half ARC, three Half ARC method and the two Full ARC were planned. The H-VMAT was planned by adding two Static fields in the VMAT, taking into account the dose of the lung and the tolerance dose of the organs. Results: In the NSCLC, the lung doses $V_5$ and $V_{10}$ of the lungs except for the treatment plan volume were the lowest with $55.40{\pm}13.39%$ and $32.05{\pm}11.37%$ of H-VMAT. And, in the SCLC, the lung doses of V5 and V10 were the lowest at $64.32{\pm}16.15%$ and $35.50{\pm}9.91%$, respectively. The spinal dose of VMAT in NSCLC was $21.15{\pm}4.02Gy$, which was 7.94 Gy lower than other treatment methods. The lowest spinal dose was delivered at $19.72{\pm}1.82Gy$ for SCLC. The mean dose delivered to the esophagus was also $17.44{\pm}2.04Gy$ and $17.84{\pm}9.20Gy$ in SCLC and NSCLC, respectively. Conclusion: When comparing the value of the surrounding normal organ dose, the VMAT showed that less doses were transmitted from the heart, esophagus and spinal cord than the rest of the treatment plan. However, it was similar to VMAT in normal organs except for the spinal cord. VMAT has increased doses of some normal organs but did not exceed the tolerance dose. It showed a low value in $V_5$, $V_{10}$. When comparing Conventional RT, VMAT, and H-VMAT, If the dose to the heart, esophagus and spinal cord is lower than the tolerance dose, it is thought to reduce the incidence of radiation pneumonia by applying H-VMAT that show the benefits of low doses of the lungs.

혀 기저부의 골성 분리종 2예

이건호,원호륜,구본석,장재원,Lee, Geonho,Won, Ho-Ryun,Koo, Bon-Seok,Chang, Jae Won 대한두경부종양학회 2019 대한두경부 종양학회지 Vol.35 No.1

Osseous choristoma is a rare, benign proliferative osseous lesion, which is defined as the growth of normal tissue in an abnormal location. The etiopathogenesis for its formation is unknown, but various hypotheses have been proposed. Treatment of choice is en-bloc resection, and no recurrence has been reported. Here, we report the two cases of osseous choristoma, presented with a mass on the base of the tongue with/without globus symptom and were treated with surgical excision.

사이버나이프 6-D Skull Tracking의 유용성 평가

이건호,배선명,송흥권,백금문,Lee, Geon Ho,Bae, Sun Myeong,Song, Heung Kwon,Baek, Geum Mun 대한방사선치료학회 2018 대한방사선치료학회지 Vol.30 No.1

Purpose : The purpose of this study is to evaluate the usefulness of 6 Dimensional Skull Tracking(6DST) in Cyberknife Stereotactic Body Radiation Therapy(SBRT) for the first and second cervical vertebrae(C1 and C2) metastasis. Methode and material : The Computed Tomography (Lightspeed VCT 64, General Electric Co. Waukesha, WI, USA) was used to acquire the CT images of the 9 patients with cervical vertebrae(C1 and C2) metastasis. Treatment plans for Xsight spine tracking and 6 Dimensional skull tracking were established with planning system (Multiplan system Version 4.6, Accuray, US). The results of XST and 6DST for each patient were analyzed with Microsoft Excel 2010. Result : The Maximum offsets of XST for C1 were 0.9 mm in Y(supero-inferior), 0.9 mm in Z(antero-posterior), 0.7 mm in X(left-right) direction, and rotations were and 1.0 degrees roll, 1.0 degrees pitch and 1.2 degrees yaw. The Maximum offsets of 6DST for C1 were 0.7 mm, 0.7 mm, 0.9 mm and $1.0^{\circ}$, $1.0^{\circ}$, $1.2^{\circ}$ for Y, Z, X and Roll, Pitch, Yaw. The Maximum offsets of XST and 6DST for C2 were 0.7 mm, 0.7 mm, 0.8 mm and $0.9^{\circ}$, $1.0^{\circ}$, $1.8^{\circ}$, and 0.9 mm, 0.7 mm, 0.9 mm and $0.9^{\circ}$, $0.9^{\circ}$, $1.0^{\circ}$ for Y, Z, X and Roll, Pitch, Yaw, respectively. Conclusion : XST and 6DST showed identical results for translations and rotations within the tolerance. It is possible to simplify the treatment time and procedure by using the 6DST. Therefore, 6DST is very useful methode with XST among the various tracking methods in Cyberknife for the patients with C1, C2 vertebral metastasis.