• 한국과학교육학회지
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• 제25권6호
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• pp.678-688
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• 2005

The main objective of this study was to investigate Korean university students' understanding of the structure of the atom based on a Lakatosian view. In this study, we examined twenty-three Korean university students' understandings of atomic structure using an open-ended questionnaire. The participants were all junior students majoring in chemistry education in Korea. The characteristics of students' understanding were categorized into three philosophical stances based on the classification criteria. Assertions were constructed concerning students' written descriptions of the development of scientific knowledge with respect to atomic structure: (a) characteristics of positivist response; (b) characteristics of transitional response; (c) characteristics of Lakatosian response; and (d) tendencies in students' responses.

• 대한안전경영과학회지
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• 제17권2호
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• pp.67-78
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• 2015

The purpose of the establishment of corporation's Business Continuity Plan(BCP) is to maintain corporations' own business and establish the response plan in order to resume operation in a short time period when crisis situations occur due to natural disaster and human error. This study has presented all types of procedures and criteria which are needed to establish the airport crisis response system in order to maintain the business continuity by utilizing BCP technique. Basically the risk response procedures must be established in the process of (1) preparation stage, (2) plan development stage, (3) documentation stage, (4) test & maintenance stage. The guideline has been suggested that each stage must be carried out in the sequence of Policy & Planning Responsibility, Business Impact Analysis, Recovery Strategy & Plans, Emergency Plan & SOP, Training Awareness and Maintenance & Review

• 정보통신설비학회논문지
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• 제4권1호
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• pp.23-29
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• 2005

This study is about designing mobile phone display in consideration of elder people's preferences by reason of their optical weakness. The research is closely connected with designing user-friendly interface by considering user characteristics. The criteria for first experiment are font sizes, font types, line spacing and background colors. With the experiment result, relative importance of each attribute and subjective preference are investigated by conjoint analysis. Secondly, an optimal display design for elder people is presented by response surface method on the basis of the result of conjoint analysis, other statistical analyses, and user interviews.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.860-861
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• 2007

This paper deals with optimum design criteria to minimize torque ripple of concentrated winding Synchronous Reluctance Motor (SynRM) using Response Surface Methodology (RSM). The feasibility of using RSM with the finite element method(FEM) in practical engineering problem is investigated with computational examples and comparison between the fitted response and the results obtained from an analytical solution according to the design variables of stator and rotor in concentrated winding SynRM (6slot).

• Structural Engineering and Mechanics
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• 제89권6호
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• pp.549-556
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• 2024

A serial pendulum dynamic vibration absorber (DVA) was designed to suppress the vibration of two degrees of freedom (Two-DOF) structure model. The optimal DVA parameters are selected using a genetic algorithm (GA) by minimizing the fitness function formulated from the system's frequency response function (FRF). Two fitness function criteria, using one and two target frequency ranges, were utilized to calculate the optimal DVA parameters. The optimized serial pendulum DVA parameters were used to reduce structural vibration under free and forced excitation conditions. The simulation study found that the serial pendulum DVA can effectively reduce the vibration response for a small excitation amplitude. However, the DVA performance decreases for a large excitation amplitude due to the nonlinearity of pendulum motion, and the percentage of vibration response attenuation is smaller than that obtained using a small excitation amplitude.

• Steel and Composite Structures
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• 제23권3호
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• pp.285-302
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• 2017

Buckling-restrained braced frames (BRBFs) are commonly used as the lateral force-resisting systems in building structures in the seismic regions. The nearly-symmetric hysteretic response and the delayed brace core fracture of buckling-restrained braces (BRBs) under the axial cyclic loading provide the adequate lateral force and deformation capacity to BRBFs under the earthquake excitation. However, the smaller axial stiffness of BRBs result in the undesirable higher residual drift response of BRBFs in the post-earthquake scenario. Two alternative approaches are investigated in this study to improve the elastic axial stiffness of BRBs, namely, (i) by shortening the yielding cores of BRBs; and (ii) by reducing the BRB assemblies and adding the elastic brace segments in series. In order to obtain the limiting yielding core lengths of BRBs, a modified approach based on Coffin-Manson relationship and the higher mode compression buckling criteria has been proposed in this study. Both non-linear static and dynamic analyses are carried out to analytically evaluate the seismic response of BRBFs fitted with short-core BRBs of two medium-rise building frames. Analysis results showed that the proposed brace systems are effective in reducing the inter-story and residual drift response of braced frames without any significant change in the story shear and the displacement ductility demands.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.275-282
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• 2006

System algorithms estimated by deterministic input may occur the error between predicted and actual output. Especially, actual system can't predict the exact outputs due to uncertainty and tolernce of input parameters. A single output to a set of inputs has a limited value without the variation. Hence, we should consider various scatters caused by the load assessment, material characteristics, stress analysis and manufacturing methods in order to perform the robust design or etimate the reliability of structure. The system design with uncertainty should perform the probabilistic structural optimization with the statistical response and the reliability. This method calculated the probability distributions of the characteristics such as stress by combining stress analysis, response surface methodology and Monte Carlo simulation and got the probabilistic sensitivity. The sensitivity of structural response with respect to in constant design variables was estimated by fracture probability. Therefore, this paper proposed the probabilistic reliability design method for fracture of uncorved freight end beam and the design criteria by fracture probability.

• 대한암한의학회지
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• 제19권1호
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• pp.25-32
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• 2014

Objectives : The purpose of this study is to report the effect of Korean Medicine Treatment (KMT) on the advanced gastric carcinoma (AGC) patient. Method : One advanced gastric carcinoma patient was treated by Korean Medicine Treatment composed of pharmacopuncture, acupuncture and herbal medicine. At the same time, he received chemotherapy (S-1 and Cisplatin) and radiotherapy. The effect of KMT was measured by scanning with Computed tomography (CT) and Esophagogastroduodenoscopy (EGD). Response was evaluated using the Response Evaluation Criteria in Solid Tumors (RECIST) Committee classification. Result : The tumor was disappeared after the treatment during 13 months (Complete Response (CR)). As treatment was performed, chemoradiation therapy induced complication was alleviated. Conclusion : This case provides us a possibility that Korean Medicine Treatment offers potential benefits for advanced gastric carcinoma patient.

• 한국지진공학회논문집
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• 제27권1호
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• pp.1-12
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• 2023

Structures of high-rise buildings are less prone to earthquake damage. This is because the response acceleration of high-rise buildings appears to be small by generally occurring short-period ground motions. However, due to the increased construction volume of high-rise buildings and concerns about large earthquakes, long-period ground motions have begun to be recognized as a risk factor for high-rise buildings. Ground motion observed on each floor of the building is affected by the eigenmode of the building because the ground motion input to the building is amplified in the frequency range corresponding to the building's natural frequency. In addition, long-period components of ground motion are more easily transmitted to the floor or attached components of the building than short-period components. As such, high-rise buildings and non-structural components pose concerns about long-period ground motion. However, the criteria (ASCE 7-22) underestimate the acceleration response of buildings and non-structural components caused by long-period ground motion. Therefore, the characteristics of buildings' acceleration response amplification ratio and non-structural components were reviewed in this study through shake table tests considering long-period ground motions.

• Radiation Oncology Journal
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• 제29권2호
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• pp.63-70
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• 2011

목 적: 간세포암에 의한 뼈전이 환자의 방사선 조사선량에 따른 통증 감소 정도 및 전이성 병소의 영상학적 치료반응을 분석하고 고선량 방사선치료가 도움이 될 수 있는지 알아보고자 하였다. 대상 및 방법: 2007년 1월부터 2010년 6월까지 병리 혹은 임상적으로 간세포암에 의한 뼈전이로 진단받고 증상 완화 목적의 방사선치료를 받은 103명에서 뼈전이 병소 2237개 부위를 대상으로 연구하였다. 조사받은 생물학적 유효선량이 39 $Gy_{10}$이하인 경우 저선량군, 39 $Gy_{10}$를 초과하는 경우 고선량군으로 대상환자를 구분하였다. 통증 감소 정도는 숫자통증등급(numeric rating scale)을 이용하였고 통증이 감소한 경우, 통증 정도에 변화가 없는 경우, 통증이 증가한 경우로 나누었다. 영상학적 반응은 modified Response Evaluation Criteria In Solid Tumors (RECIST) 기준을 이용하였으며 환자의 생존율에 영향을 미치는 인자를 분석하였다. 결 과: 중앙추적 관찰기간은 6개월이었다(범위, 0~46개월). 저선량군에서는 67개 병소(66.3%) 부위에서, 고선량군 에서는 44개 병소(89.8%) 부위에서 영상학적 반응이 있었다 저선량군과 고선량군 사이에 영상학적 치료 반응 정도는 유의하게 차이를 보였다(p=0.02). 저선량군과 고선량군은 각각 65%와 75%의 통증 감소를 보였으나 통계적으로 유의한 차이는 없었다(p=0.24). 저선량군과 고선량군 사이에 급성 및 만성 치료 독성은 통계적으로 유의한 차이가 없었다(p>0.05). 뼈전이 진단 시부터 사망까지 생존기간은 0~46개월(중앙값, 11개월) 범위였고 1년 생존율은 41.6%였다. 잔존 간 기능(Child-Pugh 점수)이 생존율에 유의한 영향을 미치는 인자였고 Child-Pugh 점수에 따른 중앙생존기간은 A 14개월, 8와 C는 2개월로 나타났다. 결 론: 간세포암에 의한 뼈전이는 고선량군에서 영상학적 반응 정도가 더 높았다. 잔존 간 기능이 좋은 환자에게 고선량의 방사선치료 시 높은 치료 반응을 얻음으로써 삶의 질의 향상에 도움을 줄 수 있음을 알 수 있었다.