• Smart Structures and Systems
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• 제21권5호
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• pp.695-703
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• 2018

Based on monitoring data collected from the Nanjing Dashengguan Bridge over the last five years, this paper systematically investigates the effects of temperature field and train loadings on the structural responses of this long-span high-speed railway bridge, and establishes the early warning thresholds for various structural responses. Then, some lessons drawn from the structural health monitoring system of this bridge are summarized. The main context includes: (1) Polynomial regression models are established for monitoring temperature effects on modal frequencies of the main girder and hangers, longitudinal displacements of the bearings, and static strains of the truss members; (2) The correlation between structural vibration accelerations and train speeds is investigated, focusing on the resonance characteristics of the bridge at the specific train speeds; (3) With regard to various static and dynamic responses of the bridge, early warning thresholds are established by using mean control chart analysis and probabilistic analysis; (4) Two lessons are drawn from the experiences in the bridge operation, which involves the lacks of the health monitoring for telescopic devices on the beam-end and bolt fractures in key members of the main truss.

• 한국염색가공학회지
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• 제19권2호
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• pp.14-23
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• 2007

This research article explores the use of phthalocyanine reactive dye on nylon substrate. The effect of factors such as pH, temperature, liquor ratio and alkali addition on level of dye exhaustion, fixation and total fixation efficiency. Low pH, high temperature and low liquor ratio were found to be suitable conditions for maximum % exhaustion values. The effect of sulphatoethylsulphone(SES) and vinylsulphone(VS) form of the dyes on level of dye fixation was also discussed. The optimized exhaustion (%E), fixation(%F) and total fixation efficiency were determined. Modification of the dyeing process with alkali addition displayed that dye fixation(%) increased by alkali addition. Vinylsulphone(VS) moiety of the dye was found to be superior to. maximum fixation (%F). Appropriate predictable empirical models, relatively a new approach in dyeing processes, were developed incorporating interactions effects of temperature, pH and liquor ratio for predicting % exhaustion, fixation and total fixation efficiency. The significance of the mathematical model developed was ascertained using microsoft excel regression(solver) analysis module. High correlation coefficient was obtained (R2=0.9895 for % exhaustion, R2=0.9932 for fixation, R2=0.9965 for total fixation efficiency) for the model which shows prominent prediction capacity of the model for my conditions. The predictable polynomial equations developed from tile experimental results were thoroughly analyzed by ANOVA (Analysis of Variance) statistical concepts.

• 보건행정학회지
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• 제29권4호
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• pp.412-421
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• 2019

Background: The purpose of this study was to identify the status of Successful Aging among the elderly aged 65 and over in rural areas and to compare factors related with Successful Aging between "kyung-ro-dang" users and non-users. Methods: A total of 181 elderly aged 65 or older were selected from four districts (Heung-upri, Mejiri, Sajerri, and Daeanri) of Wonju city. A survey method using face to face interviews was applied to collect information. Successful aging was measured on a 5-point Likert-type scale using the successful aging scale developed for the Korean elderly, which indicates the higher the score, the higher the level of successful aging. Descriptive statistics, bivariate, and multivariate analyses were computed; the level of significance was set at 5%. Hierarchical polynomial regression was applied to find out the factors associated with successful aging. Results: Of the total, 112 elders used kyung-ro-dang and 69 elders who did not use kyung-ro-dang. The level of successful aging of the elderly was higher among kyung-ro-dang users than non-users. The factors related to successful aging among kyung-ro-dang users were walking and social participation. Users who walk more than 4 times per week and social participation activities have a higher level of satisfaction. In the case of non-users, a higher level of monthly income, having a spouse, social support, and social participation associated with a higher level of successful aging. Conclusion: Monthly income, social participation, and social factors were found to be related to successful aging along with physical and mental health conditions among the elderly in rural areas. Therefore, it can be concluded that income, social as well as mental and physical factors, are more critical for successful aging in the rural community care in Korea.

• Fisheries and Aquatic Sciences
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• 제17권1호
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• pp.47-57
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• 2014

Thai Jasmine rice (Oryza sativa, long grain Indica var.) is popular in southeastern Asia and China due to its non-glutinous, fluffy texture and fragrant smell. However it has a high starch digestibility, which leads to an increased glycemic index (GI). Therefore it may require modified cooking methods for diabetes patients. The objectives of this study were to optimize the ratio of Thai Jasmine rice, sea tangle, and olive oil (CLTR) based on consumers' acceptance. The GI of plain cooked Thai Jasmine rice (CLR) was measured as a control. Sensory evaluation and response surface methodology were used to determine the optimal ratio. Texture analysis and nutritional evaluation were also performed on the optimal recipe of cooked Jasmine rice with sea tangle. A multiple regression equation was developed in quadratic canonical polynomial models. We used 26 trained Chinese panelists in their forties to rate color, flavor, adhesiveness, and glossiness, which we determined were highly correlated with overall acceptability. The optimal CLTR formula was 34.8% rice, 2.8% sea tangle, 61.9% water, and 0.5% olive oil. Compared to CLR, CLTR had a lower hardness, but a higher springiness and cohesiveness. However, CLR and CLTR had the same adhesiveness and chewiness. The addition of sea tangle and olive oil delayed retro-gradation of starch in CLTR and increased total dietary fiber, and protein and ash contents. The degree of gelatinization, and in vitro protein and starch digestibility of CLTR were lower than those of CLR. Based on Wolver' method, the GI of CLTR (52.9, incremental area under the glycemic-response curve, ignoring the area below fasting, as used for calculating the GI [Inc]) was lower compared with that of CLR (70.94, Inc), which indicates that CLTR is effective in decreasing and stabilizing blood glucose level, owing to its lower degree of gelatinization and starch digestibility. Our results show that CLTR can contribute to the development of a healthier meal for families and the fast food industry.

• 한국식품과학회지
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• 제22권5호
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• pp.497-502
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• 1990

삼투압 농축중 설탕용액의 농도와 온도 및 침지시간에 따른 감자 내부의 수분손실, 고형분 증가나 손실 및 몰랄농도를 반응 표면 분석법으로 조사하였고, 이차 다항 회귀 모델로써 예측하였다. 또한 삼투압 농축과 데치기가 6%수분(wet basis)까지 열풍조건시 비타민 C 함량유지에 미치는 효과를 평가하였다. 감자내부의 수분손실, 고형분 증가나 손실, 몰랄농도, 속도 매개변수 및 비타민 C 함량에 가장 크게 영향을 미치는 요소는 설탕농도이었고 그 다음 침지시간과 침지온도 순이었다. 수분손실과 설탕흡수는 초기 10분간 침지과정에서 빠르게 이루어진 후 증가현상이 둔화되었다. 설탕용액 $(60\;Brix,\;80^{\circ}C)$에서 20분간 침지 후 44.6%의 수분손실이 되었다. 삼투압 농축후 건조시킨 감자가 데치기 한 후 건조시킨 감자보다 높은 비타민 C 함량을 유지하였다. 30% 이상의 수분손실과 50% 이상의 비타민 C 함량유지의 관점에서 삼투압농축공정의 최적조건은 $60-70^{\circ}C$의 침지온도와 60 Brix의 설탕농도 및 16-20분간의 침지시간이었다.

• 대한전자공학회논문지SP
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• 제44권6호
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• pp.1-8
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• 2007

본 논문에서는 영상의 공간 정합과 서로 다른 노출의 보정을 동시에 최적화하기 위한 연구를 수행하였다. 노출 보정은 영상의 밝기 보정이라는 틀 안에서 두 영상의 관계식을 다항식 근사를 통하여 이루는데, 이를 가우스-뉴톤 방식의 비선형 최적화 기법을 이용하여 공간 정합과 동시에 수행을 한다. 본 논문에서는 보다 신뢰성 있고 단순한 동시 최적화를 위하여 블록 좌표(block-coordinate) 방법과의 결합을 제안하며 심도 있는 모의실험을 통하여 성능을 비교하였다. 나아가서 블록 좌표 방법의 단순성과 융통성을 이용하여 밝기 보정에 회기 분석 기법을 도입하여 여러 종류의 영상에 대하여 안정성에서도 우수한 성능을 보이는 최적화를 수행하였다. 기존의 가우스-뉴톤 최적화에 블록 좌표 방법을 결합하여 일반 가우스-뉴톤 최적화에 비하여 계산을 단순화시키면서 보다 빠르게 수렴하는 특성을 보이며 대등한 성능의 칙적화를 수행할 수 있었다. 실험 결과를 보면 특정 영상에서 10회 반복정도로 원하는 수렴 결과를 얻었는데 이는 알고리듬 수행을 위한 계산을 50%정도 감소시킨 것이다 또한 에러도 1.5dB이상 감소시켰다.

• 전자공학회논문지
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• 제50권11호
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• pp.188-194
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• 2013

본 논문에서는 폐 영상에서 폐 혈관을 분할하고 정제하는 방법을 제안하였다. 제안된 방법은 다음과 같이 다섯 단계로 구성된다. 첫 번째, 폐 영상에서 히스토그램 변화율의 다항식 회귀 분석을 사용하여 임계값을 계산한다. 두 번째, 계산된 임계값으로 밝기값 기반 분할 방법을 사용하여 폐 혈관을 분할한다. 세 번째, 분할한 폐 혈관 영상에 2차원 연결 요소 레이블링 방법을 사용하고, 레이블링 요소의 크기와 이심률을 계산하여 좌측 및 우측 횡격막의 씨앗점을 결정한다. 네 번째, 결정된 씨앗점에서 3차원 영역 성장법을 사용하여 횡격막을 추출한다. 다섯 번째, 이진 영상의 3차원 연결 요소 레이블링 방법을 사용하여 폐 혈관 영상의 노이즈를 제거한다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집B
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• pp.501-506
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• 2001

Computer modeling is essential to evaluate possible design of suspension for a railway vehicles. By creating a simulation, the engineers are able to assess the feasibility of a given design and change the design factors to get a better design. But if one wishes to perform complex analysis on the simulation, such as railway vehicle dynamic, the computational time can become overwhelming. Therefore, many researchers have turned to surrogate modeling. A surrogate model is essentially a regression performed on a data sampling of the simulation. In the most general sense, metamodels(surrogate model) take the form $y(x)=f(x)+{\varepsilon}$, where y(x) is the true simulation output, f(x) is the metamodel output, and $\varepsilon$ is the error between the two. In this paper, a second order polynomial equation is partially used as a metamodel to represent the forty-six dynamic performances for high speed train. The number of factors as design variables of the metamodel is twenty-nine, which are composed the dynamic characteristics of suspension. This metamodel is used to search the optimum values of suspension characteristics which minimize the dynamic responses for high speed train. This optimization is a multi-objective problem which have many design variables. This paper shows that the response surface model which is made through the design of analysis of computer experiments method is very efficient to solve this complex optimization problem.

• 한국식품저장유통학회지
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• 제10권3호
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• pp.314-319
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• 2003

가지의 수출 경쟁력 향상을 위한 한 방안으로 수출용 가지품종인 축양품종을 염가공품으로 개발하기 위하여 염절임 공정을 최적화하였다. 염절임 시간, 절임온도, 염농도를 독립변수로 하고 절임 후 수분함량, 염도, 표면과 내부의 색도 등을 종속변수로 하여, 중심합성계획법으로 실험을 설계하여 최적조건을 얻고자 하였다. 수립된 이차회귀모형으로 예측식을 수립할 수 있었으며 특히 수분함량이나 염도, 표면과 내부의 L과 b 값에 대하여 높은 적합도를 보여 최적조건을 수립하기 위한 제한 변수로 선정하였다. 염농도를 중심점(30%)에서 고정시켜서 얻은 절임시간과 온도는 각각 5.5-6.5일과 13-17$^{\circ}C$였으며, 이때의 종속변수의 제한 요건으로는 수분함량 84%이하, 염도 14%이하 표면 L 값 10-20, b값 0 이하, 내부 L 값은 70-75, b 값이 16-18이었다.

• 한국식품저장유통학회지
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• 제10권3호
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• pp.320-325
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• 2003

대부분의 마는 건조분말제품으로 가공되고 있는데, 마를 다양한 가공품으로 개발하기 위한 방법의 하나로 삼투건조라는 전처리를 행하여 건조에 의한 품질손상을 억제하고 단맛으로 기호성을 높인 건조 마 제품을 얻을 수 있는 당절임 공정의 최적화를 시도하여 최적조건을 얻고자 하였다. 침지시간을 3-7시간, 온도는 20-6$0^{\circ}C$, 당농도는 30-70%로 하는 중심합성계획법으로 실험을 설계하여 최적화하였다. 이때의 종속변수로는 침지 후 수분함량, 당도, 색도, 그리고 동결건조후의 수분함량과 재수화율로 하여 분석한 결과 동결건조 후 수분함량에 대해서는 유의성이 없었다. 세 가지의 공정 변수 중 온도의 영향이 가정 적어 온도를 중심으로 고정한 후 침지시간과 당농도의 최적조건을 찾은 결과, 수분함량을 66-70%, 당도를 25-30%, L 75이상, a -2.1--2.4, b를 5이상 그리고 재수화율을 200-250을 제한 조건으로 하는 영역은 5.2-5.9시 간, 56-61%로 나타났다.