• 한국공간구조학회논문집
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• 제12권2호
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• pp.89-98
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• 2012

본 연구는 공간 트러스의 전체 좌굴을 고려한 최적 구조설계에 대해 연구를 하였으며, 구조물의 최소중량을 구하는 것이 목적이다. 응력제약에 의한 부재 최적화를 위해서 수리 계획법이 사용되었으며, 뜀-좌굴을 고려하기 위해 동적 계획법을 적용하였다. 트러스 부재의 최적설계를 위한 수리 모형은 전체중량 목적함수와 인장 또는 압축 허용응력 및 세장비 제약식으로 구성하였다. 평형경로상의 임계점 즉 좌굴하중을 구하기 위해서 접선 강성행렬의 행렬식 변화를 조사하였으며, 설계하중에 대한 좌굴하중 비율이 동적계획법의 반복계산과정에서 공간 트러스의 강성을 조절하기위해 반영되었다. 제안된 최적설계 프로세서의 검증을 위해서 스타 돔 구조물 예제를 통해 조사하였으며, 수치 결과는 잘 수렴하고 모든 제약을 만족하였다. 제시된 최적설계 프로세스는 전체좌굴을 고려한 최적설계를 수행하기 위한 비교적 간단 방법이고, 실무 구조설계를 반영하는데 가능하다.

• 정보처리학회논문지A
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• 제8A권4호
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• pp.489-498
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• 2001

본 논문에서는 하이퍼볼릭 평면에서 임의의 분산 데이터 보간을 지역적으로 제어하는 새로운 방법을 개발하였다. 지역적 제어와 관련된 주제는 상호대화형식의 디자인분야에서 매우 중요하다. 특히 본 논문에서 제안한 방법은 하이퍼볼릭 평면상에서 형성되는 genus-N 객체 모델을 상호대화형식으로 디자인하는데 유효하게 적용될 수 있다. 특 변화된 데이터가 미치는 영향이 일정한 지역에만 국한되므로 일반 사용자가 genus-N객체를 상호대화형으로 디자인하기가 훨씬 편리하다. 따라서, 본 연구은 genus-N 객체를 형성하는데 사용한 하이퍼볼릭 평면상에서의 전역적 보간법을 발전시켜 하이퍼볼릭 평면에서의 지역적 보간법개발 및 구현을 목적으로 하고 있다. 이는 다음과 같은 주요 과정을 통하여 구현된다. 먼저, 보간 함수를 지역화하기 위하여 하이퍼볼릭 영역을 임의의 삼각형 패치로 세분화하고 각 데이터에 인접한 삼각형 패치들의 모임을 부 영역이라고 정의한다. 각 부 영역에서 가중치 함수가 설정된다. 마지막으로 중첩된 삼각형 영역의 세 개의 가중치를 혼합함으로써 지역적 보간 함수가 완성된다. 그 결과로서, 여러 개의 샘플 데이터 및 함수를 사용하여 전역적MQ 보간법과 비교한다.

• 대한건축학회논문집:구조계
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• 제36권5호
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• pp.177-185
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• 2020

The building energy performance indicator, called Energy Performance Index (EPI), has been used for the past decades in South Korea. It has a list of design variables assigned with weighting factors (a, b). Unfortunately, the current EPI method is not performance-based but very close to a prescriptive rating. With this in mind, this study aims to propose a new performance-based EPI method. For this purpose, a global sensitivity analysis method, Sobol, is employed. The Sobol method is suitable for complex nonlinear models and can decompose all the output variance due to every input. The Sobol sensitivity index of each variable is defined as 0 to 1 (0 to 100%), and the sum of all sensitivity indices is equal to 1 (100%). In this study, an office building was modeled using EnergyPlus and then the Latin Hypercube Sampling (LHS) was conducted to generate a surrogate model to EnergyPlus. The sensitivity index was suggested to replace weight (a) in the existing EPI. In addition, the discrete weight (b) in the existing EPI was replaced by a set of continuous regression functions. Due to the introduction of the sensitivity index and the continuous regression functions, the new proposed approach can provide far more accurate outcome than the existing EPI (R²: 0.83 vs. R²: 0.01 for cooling, R²: 0.66 vs. R²: 0.01 for total energy). The new proposed approach proves to be more rational, objective and performance-based than the existing EPI method.

• 한국환경과학회지
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• 제32권11호
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• pp.745-756
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• 2023

Growing stringent global regulations in Korea poses a threat to corporate sustainability. Companies must respond strategically to navigate these regulations and avoid greenwashing. Objective of this research was to analyze how Korean companies are responding to the global trend of reducing plastic use and propose improved management strategies. Seven indicators were developed to assess companies' post-plastic strategies and applied to analyze the sustainability reports of Amore Pacific and LG Household & HealthCare. These indicators included, 1) disclosure of plastic raw materials used by weight or volume, 2) disclosure of recycled plastic raw materials used by weight or volume, 3) disclosure of waste recycling, reuse amounts, and disposal using waste treatment method 4) strategies to reduce environmental impact of plastics, 5) plastic packaging, reduce, recycle, reuse, and composting (in the real environment), 6) plastic management roadmap for the circular economy, and 7) education for sustainable plastic management. Based on the review of considered companies, we propose in-listed sustainable plastics management strategies: disclosing the ratio of plastic raw materials and recycled raw materials for all products, considering recycling rate throughout the product value chain, and not only for the production phase, reviewing carbon dioxide emissions based on life cycle assessment rather than reducing plastic consumption, studying the biodegradability of biodegradable plastics in natural environment such as soil, considering the consumer's perspective.

• ETRI Journal
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• 제37권2호
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• pp.406-416
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• 2015

Timing plays a key role in expressing the qualitative aspects of a character's motion; that is, conveying emotional state, personality, and character role, all potentially without changing spatial positions. Temporal editing of locomotion style is particularly difficult for a novice animator since observers are not well attuned to the sense of weight and energy displayed through motion timing; and the interface for adjusting timing is far less intuitive to use than that for adjusting pose. In this paper, we propose an editing system that effectively captures the timing variations in an example locomotion set and utilizes them for style transfer from one motion to another via both global and upper-body timing transfers. The global timing transfer focuses on matching the input motion to the body speed of the selected example motion, while the upper-body timing transfer propagates the sense of movement flow - succession - through the torso and arms. Our transfer process is based on key times detected from the example set and transferring the relative changes of angle rotation in the upper body joints from a timing source to an input target motion. We demonstrate that our approach is practical in an interactive application such that a set of short locomotion cycles can be applied to generate a longer sequence with continuously varied timings.

• 대한기계학회논문집A
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• 제26권2호
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• pp.406-414
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• 2002

A new approach, referred to as a successive zooming genetic algorithm (SZGA), is Proposed for identifying a global solution for continuous optimization problems. In order to improve the local fine-tuning capability of GA, we introduced a new method whereby the search space is zoomed around the design point with the best fitness per 100 generation. Furthermore, the reliability of the optimized solution is determined based on the theory of probability. To demonstrate the superiority of the proposed algorithm, a simple genetic algorithm, micro genetic algorithm, and the proposed algorithm were tested as regards for the minimization of a multiminima function as well as simple functions. The results confirmed that the proposed SZGA significantly improved the ability of the algorithm to identify a precise global minimum. As an example of structural optimization, the SZGA was applied to the optimal location of support points for weight minimization in the radial gate of a dam structure. The proposed algorithm identified a more exact optimum value than the standard genetic algorithms.

• 한국환경농학회지
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• 제28권4호
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• pp.435-441
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• 2009

In the present study, we analyzed the defensin protein deduced from Korean radish (Raphanus sativus L.) seeds.To express the genes in E. coli, we constructed a recombinant expression vector with a defensin gene, named rKRs-AFP gene isolated from Korean radish seeds. Over expressed rKRs-AFP proteins was separated by SDS-PAGE to determine the purity, and protein concentration was determined by the Bradford method. Antifungal activity was assessed by disk assay method against the tested fungi. As a result, when 500 mL of cell culture were disrupted by sonicator, 32.5 mg total proteins were obtained. The purified protein showed a single band on SDS-PAGE with estimated molecular weight about 6 KDa, consistent with the molecular mass calculated from the deduced amino acid sequence. The purified rKRs-AFP protein showed remarkable antifungal activities against several fungi including Aspergillus niger, Botrytis cinerea causing the gray mold disease, and Candida albicans. In field tests using the purified rKRs-AFP protein, the protein showed the reducing activity of disease spot and the mitigating effect of spreading of disease like agrichemicals. The immuno-assay of rKRs-AFP protein showed that the purified protein entirely accumulated at B. cinerea cytoplasm through the hyphal septa shown by fluorescence imaging. There was no fluorescence inside the cell, when the hypha was incubated without the protein. These all results indicate that the recombinant rKRs-AFP proteins can be utilized as a potential antifungal drug to control harmful plant fungal pathogens.

• 자원ㆍ환경경제연구
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• 제9권2호
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• pp.349-371
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• 2000

Data Envelopment Analysis model is a linear programming based technique for measuring the relative performance of organizational units where the presence of multiple inputs and outputs makes comparison difficult. A common measure for relative efficiency is weighted sum of outputs divided by weighted sum of inputs. DEA model allows each unit to adopt a set of weight that shows it in the most favorable light in comparison to the other unit. In this paper, we present the mathematical background and characteristics of DEA model, and give a short case study where we apply the DEA model to evaluate the relative efficiencies of 51 global electricity companies. The technical efficiency and scale efficiency are also to be investigated. Generating capacity and the number of employees are used for input data, and revenue, net profit and electricity sales are used for output data. We find that the companies with 100% relative efficiency are only 9 among 51 electricity companies. And the technical and scale efficiency of KEPCO is 98.7% and 78.89%, respectively. This means that the inefficiency of KEPCO is caused by the scale inefficiency. The analysis shows that the employees should be decreased by 15% at minimum to get the 100% efficiency. The result suggests that KEPCO needs the structural reform to improve the efficiency.

• Journal of Nutrition and Health
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• 제36권7호
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• pp.749-758
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• 2003

Malnutrition is a common problem in patients undergoing maintenance hemodialysis (HD) and compromised food intake is an important cause. Malnutrition is one of the important factors influencing mortality in these patients. This study was conducted to evaluate the effectiveness of nutrition education at improving nutritional status of 23 Korean HD patients (mean : 48.6 $\pm$ 10.4 years, men : 8, women : 15). Anthropometric indices, nutrient intakes, and biochemical blood indices were measured before and after a 6-month nutrition education intervention. Anthropometric indices such as percent ideal body weight [PIBW (%)], body fat, body mass index (BMI), mid-arm circumference (MAC), mid-arm muscle circumference (MAMC), and calculated arm muscle area (CAMA) of subjects were within the normal range and not changed by nutrition education. Subjective global assessment (SGA) was significantly increased (p < 0.05) after nutrition education. Intake of total energy, carbohydrate, lipid, Ca, and vitamin B1 was increased significantly (p < 0.05) but intake of phosphorus, potassium, and sodium was decreased (p < 0.05). The serum concentrations of albumin, total protein, and Ca were significantly increased (p < 0.05), but levels of P and K were decreased (p < 0.05) after the intervention. These findings suggest that nutrition education for HD patients can be effective for positively changing nutrient intakes, leading to improvements in blood indices and nutritional status.

• Clinical and Experimental Pediatrics
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• 제58권8호
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• pp.313-316
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• 2015

Interstitial deletions involving the chromosome band 15q22q24 are very rare and only nine cases have been previously reported. Here, we report on a 12-day-old patient with a de novo 15q22q23 interstitial deletion. He was born by elective cesarean section with a birth weight of 3,120 g at 41.3-week gestation. He presented with hypotonia, sensory and neural hearing loss, dysmorphism with frontal bossing, flat nasal bridge, microretrognathia with normal palate and uvula, thin upper lip in an inverted V-shape, a midline sacral dimple, severe calcanovalgus at admission, and severe global developmental delay at 18 months of age. Fluorescence in situ hybridization findings confirmed that the deleted regions contained at least 15q22. The chromosome analysis revealed a karyotype of 46,XY,del(15) (q22q23). Parental chromosome analysis was performed and results were normal. After reviewing the limited literature on interstitial 15q deletions, we believe that the presented case is the first description of mapping of an interstitial deletion involving the chromosome 15q22q23 segment in Korea. This report adds to the knowledge of the clinical phenotype associated with the 15q22q23 deletion.