• 대한두경부종양학회지
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• 제33권2호
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• pp.23-27
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• 2017

Background and Objectives: Gastric acid reflux is known to be the most important cause of contact granuloma. Therefore, anti-gastric acid reflux medication has been used as the first line treatment although there are other treatment methods such as surgery or steroid injections. Actually, the role of surgery in the treatment of contact granuloma has not been established clearly. The purpose of this study was to evaluate the effectiveness of surgical treatment for contact granuloma. Materials and Methods: We retrospectively reviewed the medical records of 14 patients who were diagnosed with contact granuloma and treated with surgery from 2011 to July 2016 at Hanyang University hospital. Results: Of 14 patients, 9 (64.3%) were male and 5 (27.4%) were female. The mean age was 53.8 (${\pm}6.1$) years. The main symptoms were voice change followed by globus, dyspnea, and asymptomatic. Mean Reflux Finding Score (RFS) before surgery was 13.5 and mead Reflux Symptom Index (RSI) was 10.4. The causes of surgery were inadequate response to proton pump inhibitor (PPI) in 4 cases, airway obstruction with large granuloma in 8 cases, and differential diagnosis in 2 cases. Of 14 patients, recurrence occurred in 8 (53.3%) patients after surgery. In 8 recurrent cases, 5 patients showed complete remission and 3 patients showed partial remission with PPI medication. Conclusion: The role of surgery in the treatment of contact granuloma might be limited due to high recurrence rate.

• 한국실내디자인학회논문집
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• 제24권1호
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• pp.93-103
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• 2015

This study set out to figure out the tendencies of the staff members participating in the space design of Blade Runner and compare and analyze its set and location characteristics with its narrative based on Gilles Deleuze' Simulacrum, one of the basic theories of Post modernism, thus identifying the characteristics of postmodern space inherent in it. The findings were as follows: first, the spaces in a Late modernism tendency in Blade Runner seem to have been created by the cinematic imagination of Syd Mead and Douglas Trumbull rather than being influenced by the old Late modernism architecture. Second, the postmodern spaces of the movie were designed to depict a more realistic future by reinforcing the old ornamental elements or adding the mechanical aesthetics of Late modernism based on a prediction of future cities. Third, the characters representing Late modernism and Post modernism in the narrative of the movie embrace the tendencies of the parties objected by Model and Simulacrum in the scenes where they deny the tendencies of the spaces to which they belong, thus exhibiting a dual trend. Fourth, the dual narrative of Model and Simulacrum holds duality even in the space and architecture of the movie, which is the reason why the movie chose postmodern spaces reflecting historical contexts instead of inner spaces in the tendency of minimalism, which was in vogue when SF movies were made those days. Finally, the spaces of the movie can be categorized according to the Late modernism and Post modernism tendencies from the perspective of the 1980s and be understood to show the architecture and space of future Post modernism feasible through the layering of historicity, locality, and mechanical aesthetics from ancient Maya to a future city in Los Angeles, the background of the movie, from the perspective of 2019.

• 한국지진공학회논문집
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• 제12권6호
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• pp.13-23
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• 2008

본 논문에서는 거더교 형식을 갖는 교량구조물의 격자 유한요소모델에 대한 모델개선을 위해 하이브리드 유전자 알고리즘에 기초한 유한요소 모델개선기법을 제안하였다. 하이브리드 유전자 알고리즘은 유전자 알고리즘과 심플렉스 최적화방법에 기초한 직접탐색기법으로 구성하였다. 제안된 기법에 적용할 수 있도록 고유진동수, 모드형상 및 정적 처짐에 대한 계측값과 유한요소해석 결과를 사용한 적합함수를 제시하고, 강성과 질량을 동시에 개선할 수 있도록 이들 세 가지 적합함수의 선형 조합 형태를 갖는 다중목적함수를 제시하였다. 제안된 방법은 2경간 연속 격자 유한요소모델의 수치예제와 단경간 플레이트 거더교에 대하여 검증하였다. 수치예제의 경우, 랜덤 노이즈를 고려한 계측오차의 영향을 수치해석적으로 평가하였다. 수치해석과 실험적 검증을 통해, 제안된 방법이 거더교 형식의 교량에 대한 유한요소 모델개선에 적합하고 효과적임을 검증하였다.

• 지역사회간호학회지
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• 제31권2호
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• pp.166-178
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• 2020

Purpose: This study was conducted to examine the effects of the oral care program for improving swallowing function of the elderly using welfare centers on depression, self efficacy, subjective oral health status and swallowing related quality of life. Methods: The intervention in this study was systematically developed through the six stages of Intervention Mapping Protocol (IMP) and was based on Mead's symbolic interaction theory and Bandura's self efficacy theory. A non equivalent control group pre and post-test design was conducted on a total of 37 elderly people (experimental group: 19, control group: 18) from D city. The oral care program was administered to the experimental group once a week for five weeks, totaling five times, and the exact program ran for 50 minutes. The collected data were analyzed using the SPSS/WIN 25.0 program. Results: Following the intervention, subjective oral health score, and swallowing related quality of life were significantly improved in the experimental group. Conclusion: The oral care program presented in this study was found to be effective in increasing subjective oral health status, and swallowing related quality of life for the elderly using welfare centers.

• 한국환경과학회지
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• 제24권11호
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• pp.1547-1550
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• 2015

Fuji apple variety introduced in Japan has excellent storage quality and good taste so it is most commonly cultivated in the Korean Peninsula. Accurate prediction of harvest maturity allows farmers to more efficiently manage their farm, such as working time, fruit storage, market shipment and labor distribution so it is very important. This study was carried out to predict the harvest maturity of 'Fuji' apple using DTS (Days Transformed to Standard temperature) model based on the Arrhenius law in the Gunwi province of the South Korea. Input data are daily average temperature and apple harvest maturity. Predicted the harvest maturity of Fuji apple after estimating the optimal parameters by using the Nelder-Mead method. The differences of observed and predicted harvest maturity day are approximately 1 to 4 days and the RMSE is 2.9.

• International Journal of Fluid Machinery and Systems
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• 제2권4호
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• pp.392-399
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• 2009

The paper concerns the description of the step by step development process of the new fixed blade runner called "Mixer" suitable for the uprating of the Francis turbines units installed at the older low head hydropower plants. In the paper the details of hydraulic and mechanical design are presented. Since the rotational speed of the new runner is significantly higher then the rotational speed of the original Francis one, the direct coupling of the turbine to the generator can be applied. The maximum efficiency at prescribed operational point was reached by the geometry optimization of two most important components. In the first step the optimization of the draft tube geometry was carried out. The condition for the draft tube geometry optimization was to design the new geometry of the draft tube within the original bad draft tube shape without any extensive civil works. The runner blade geometry optimization was carried out on the runner coupled with the draft tube domain. The blade geometry of the runner was optimized using automatic direct search optimization procedure. The method used for the objective function minimum search is a kind of the Nelder-Mead simplex method. The objective function concerns efficiency, required net head and cavitation features. After successful hydraulic design the modal and stress analysis was carried out on the prototype scale runner. The static pressure distribution from flow simulation was used as a load condition. The modal analysis in air and in water was carried out and the results were compared. The final runner was manufactured in model scale and it is going to be tested in hydraulic laboratory. Since the turbine with the fixed blade runner does not allow double regulation like in case of full Kaplan turbine, it can be profitably used mainly at power plants with smaller changes of operational conditions or in case with more units installed. The advantages are simple manufacturing, installation and therefore lower expenses and short delivery time for turbine uprating.

• 대한조선학회논문집
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• 제29권2호
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• pp.115-122
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• 1992

Sandwich구조는 복합구조의 특별한 hybrid구조의 형태로써 두 층의 얇은 표면재와 가운데 두꺼운 층인 경량의 심재로 구성되어 있으며, 이는 표면재와 심재가 접착된 일체로써 서로의 단점을 보완하면서 구조 효율을 높인 형상이다. 또한 심재는 표면재에 비해서 상당히 두꺼운 두께를 갖기 때문에 전단 변형이 중요하므로 굽힘 강성도(bending stiffness) 계산에 전단효과가 고려되어야 한다. 구조 설계에서 중요한 목적은 중량 감소에 있기 때문에 본 논문에서는 sandwich panel의 설계시 표면재와 심재의 두께 및 재질을 변화시켜 제한조건에 맞는 최소 중량을 얻는 데 중점을 두었다. 본 해석에서 sandwich panel의 최소중량을 얻기 위하여 표면재와 전단력을 고려한 심재의 변형에 따른 변형에너지를 각각 계산한 후, 최소 potential 에너지 원리를 적용하여 목적함수의 최적치를 구하였다. 설계 제한조건으로는 허용 처짐, 허용 굽힘응력, 허용 전단응력과 국부적인 불안정 상태의 wrinkling 응력이 고려되었으며, 설계 모델은 수직 분포 하중에 의한 여러가지 경계조건에 따른 sandwich panel을 대상으로 하였다. 비선형 최적화 기법은 Nelder and Mead Simplex Search Method와 Hooke and Jeeves Pattern Search method에 External Penalty Function이 적용된 SUMT방법을 결합시킨 SUMTNM와 SUMTHJ를 사용하였으며, 해석 결과는 sandwich panel의 구조 설계에 활용할 수 있도록 표를 작성하였다.

• 한국산학기술학회논문지
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• 제12권7호
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• pp.3103-3108
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• 2011

탄소원으로 꿀을 사용하여 제조한 버찌-꿀술의 이화학적 특성을 분석하였다. 버찌-꿀술의 발효는 Saccharomyces bayanus (EC-118)를 스타터균으로 하여 발효액 2 L를 사용하여 30일 동안 진행하였다. 발효전 발효액에서 가장 많은 탄수화물은 과당이었으며, 포도당과 설탕 순으로 나타났다. 발효기간 동안 포도당은 효모균에 의하여 과당보다 빠르게 이용되어 사라졌으며, 발효기간이 진행됨에 따라 과당/포도당 비는 증가함을 보였다. 발효액의 pH와 효모 생균수는 발효 초기 5일 동안 급격하게 변화하였으나 발효액의 $^{\circ}Brix$(%)는 30일 기간 동안 점진적으로 감소하였다. 최종적으로 완성된 버찌-꿀술은 산가 0.43%, pH 3.5, $9.7^{\circ}Brix$(%), 에탄올 농도 14%였다. 버찌-꿀 술의 양조특성을 규명하였으므로 추가적인 버찌의 기능성이 확보된다면 버찌-꿀 술의 개발가능성이 충분히 있다.

• Earthquakes and Structures
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• 제5권1호
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• pp.83-109
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• 2013

A simple damper optimization method is proposed to find optimal damper allocation for shear buildings under both target added damping ratio and interstorey drift ratio (IDR). The damping coefficients of added dampers are considered as design variables. The cost, which is defined as the sum of damping coefficient of added dampers, is minimized under a target added damping ratio and the upper and the lower constraint of the design variables. In the first stage of proposed algorithm, Simulated Annealing, Nelder Mead and Differential Evolution numerical algorithms are used to solve the proposed optimization problem. The candidate optimal design obtained in the first stage is tested in terms of the IDRs using linear time history analyses for a design earthquake in the second stage. If all IDRs are below the allowable level, iteration of the algorithm is stopped; otherwise, the iteration continues increasing the target damping ratio. By this way, a structural response IDR is also taken into consideration using a snap-back test. In this study, the effects of the selection of upper limit for added dampers, the storey mass distribution and the storey stiffness distribution are all investigated in terms of damper distributions, cost function, added damping ratio and IDRs for 6-storey shear building models. The results of the proposed method are compared with two existing methods in the literature. Optimal designs are also compared with uniform designs according to both IDRs and added damping ratios. The numerical results show that the proposed damper optimization method is easy to apply and is efficient to find optimal damper distribution for a target damping ratio and allowable IDR value.

• Smart Structures and Systems
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• 제23권6호
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• pp.615-626
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• 2019

Inerter-based damping devices (IBBDs), which consist of inerter, spring and viscous damper, have been extensively investigated in vehicle suspension systems and demonstrated to be more effective than the traditional control devices with spring and viscous damper only. In the present study, the control performance on cable vibration reduction was studied for four different inerter-based damping devices, namely the parallel-connected viscous mass damper (PVMD), series-connected viscous mass damper (SVMD), tuned inerter dampers (TID) and tuned viscous mass damper (TVMD). Firstly the mechanism of the ball screw inerter is introduced. Then the state-space formulation of the cable-TID system is derived as an example for the cable-IBBDs system. Based on the complex modal analysis, single-mode cable vibration control analysis is conducted for PVMD, SVMD, TID and TVMD, and their optimal parameters and the maximum attainable damping ratios of the cable/damper system are obtained for several specified damper locations and modes in combination by the Nelder-Mead simplex algorithm. Lastly, optimal design of PVMD is developed for multi-mode vibration control of cable, and the results of damping ratio analysis are validated through the forced vibration analysis in a case study by numerical simulation. The results show that all the four inerter-based damping devices significantly outperform the viscous damper for single-mode vibration control. In the case of multi-mode vibration control, PVMD can provide more damping to the first four modes of cable than the viscous damper does, and their maximum control forces under resonant frequency of harmonic forced vibration are nearly the same. The results of this study clearly demonstrate the effectiveness and advantages of PVMD in cable vibration control.