• Journal of Power Electronics
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• 제17권4호
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• pp.914-922
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• 2017

Multilevel converters have attracted a lot of attention in recent years. The efficiency parameters of a multilevel converter such as the switching losses and total harmonic distortion (THD) mainly depend on the modulation strategy used to control the converter. Among all of the modulation techniques, the selective harmonic elimination (SHE) method is particularly suitable for high-power applications due to its low switching frequency and high quality output voltage. This paper proposes a new expression for the SHE problem in five-level converters. Based on this new expression, a simple analytical method is introduced to determine the feasible modulation index intervals and to calculate the exact value of the switching angles. For each selected harmonic, this method presents three-level or five-level waveforms according to the value of the modulation index. Furthermore, a flowchart is proposed for the real-time implementation of this analytical method, which can be performed by a simple processor and without the need of any lookup table. The performance of the proposed algorithm is evaluated with several simulation and experimental results for a single phase five-level diode-clamped inverter.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -1
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• pp.281-284
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• 2002

Error resilience for image coding is an important component of multimedia communication system. Error resilience schemes address loss recovery from the compression perspective. Multiple description coding (MDC) is one of the error resilience techniques promising for robust video transmission. It is the way to achieve tradeoff description such as scalar quantization, correlating transform and the quantized frame expansion. In this paper, we consider Multiple Description Scalar Quantization (MDSQ) to wavelet domain. Conventional MDSQ schemes considered description with equal weights in each sub-bands. But, we can see that the each sub-bands is unequal contribution to whole image quality. Therefore, we experiment the multiple design MDSQ table to make probability of zero index high, which gives high efficiency in arithmetic symbol coder. We also compare our proposed method with the conventional methods and show improved performance in terms of redundancy-rate-distortion.

• 한국막학회:학술대회논문집
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• 한국막학회 1996년도 제4회 하계분리막 Workshop (초순수 제조와 막분리 공정)
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• pp.121-147
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• 1996

Since 1980, the water quality of ultra-pure water has been rapidly improved, and presently ultra-pore water producing equipment for 64Mbit is in operation. Table 1 shows the degree of integration of DRM and required water quality exlmple. The requirements of the ultra-pure water for 64Mbit are resistivity: 18.2 MQ/cm or higher, number of particulates: 1 pc/ml or less (0.05 $\mu$m or larger). bacteria count: 0.1 pc/l or less. TOC (Total Organic Carbon, index of organic snbstance) : 1ppb or less, dissolved oxygen: 5ppb or less, silica: 0.5ppb or less, heavy metal ions: 5ppb or less. The effect of metals on the silicon wafer has been well known, and recently it has been reported that the existence of organic substance in ultra-pure water is closely related to the device defect, drawing attention. It is reported that if organic substance sticks to the natural oxidation film, the oxide film remaims on the organic substance attachment in the hydrofluoric acid treatment (removal of natural oxidation film). The organic substance forms film on the silicon wafer, and harmful elements such as metals and N.P.S., components contained in the organic substance and the bad effect due to the generatinn of silicon carbide cannot be forgotten. In order to remove various impurities in raw water, many technological develoments (membrane, ion exchange, TOC removal, piping material, microanalysis, etc.) have been made with ultra-pure water producing equipment and put to practical use. In this paper, technologies put to practical use in recent ultra-pure vater producing equimeut are introduced.

• Journal of Nutrition and Health
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• 제39권6호
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• pp.529-538
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• 2006

The prevalence of chronic diseases have been rising in the developing countries because of their increased animal foods consumption and Western lifestyle. Lately, vegetarian diet that exclude animal products get public attention. The purpose of this study was to evaluate the nutritional status and dietary quality of vegetarians, and their consumption of vitamin K and was also assessed. Vegetarians including strict vegan and lacto-ovo-vegetarian consumed their diet at least over 6 months. Carnivores were gender and age matched with vegetarians and they consumed over 50% of protein and fat from animal sources. Current nutrient intakes and dietary quality were assessed using 3-day food records and intake of vitamin K was calculated from the data base of 'Provisional Table on the vitamin K contents of foods, USA'. Blood sample were collected and biochemical parameters and plasma phylloquinone concentrations were analyzed. Anthropometric data from vegetarian and carnivore were not significantly different. The intake of calories, protein, vitamin $B_2$, Ca and Zn of the vegetarians were remarkably lower than RDA for each nutrient. Moreover, index of nutritional quality and nutrient adequacy ratio of vegetarians were lower than those of carnivore. Vegetarian consumed less fat and the ratio of n-6/n-3 fatty acid was lower in vegetarian. The intake of essential amino acids in vegetarian was significantly lower than that of carnivore. The vitamin K consumption and plasma phylloquinone concentration of vegetarian were significantly higher than those of carnivore (p<0.05). The dietary vitamin K consumption was positively correlated with plasma phylloquinone levels in vegetarian (p<0.01).

• 한국유통학회지:유통연구
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• 제16권1호
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• pp.95-115
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• 2011

본 연구는 Kano모델을 활용하여 프랜차이즈 매장에 관한 다양한 품질요인들의 속성을 고객의 관점에서 분류하였다. 또한, 각 품질요인들이 고객의 만족 또는 불만족에 미치는 상대적 영향력을 분석해 보고자 만족지수와 불만족지수를 산출하였다. 자료 수집을 위해 외식 프랜차이즈 매장 방문 경험이 있는 서울 및 전국광역시 거주 성인들을 대상으로 온라인조사를 실시하였으며, 총 257개의 응답이 분석에 사용되었다. 분석 결과, 해당 품질요소가 충족이 되지 않는 경우 소비자의 불만으로 이어지는 요소에는 매장 청결도, 직원 친절도 및 숙련도, 편의시설 제공 등이 포함되는 것으로 나타났다. 프랜차이즈 사업에서 매장 간 음식메뉴의 구색, 가격, 품질수준, 인테리어, 고객서비스 절차 등의 표준화는 중요하게 생각되어 왔으나, 이 중 음식 가격의 동일성만이 고객의 불만족과 깊은 관계를 가지고 있었다. 충족이 되지 않아도 상관없지만 충족이 되는 경우 고객들의 호의적인 반응을 이끌어낼 수 있는 요소로는 외부기관으로부터의 수상 또는 인증 경력, 프랜차이즈 브랜드의 해외진출, 경품이벤트 및 사용금액에 따라 혜택을 주는 로열티 프로그램의 실시, 그리고 우수한 매장접근성이 해당되었다. 프랜차이즈 브랜드를 상대적으로 자주 이용하는 헤비유저의 경우, 정기적인 신메뉴 출시 또한 매력적인 품질요인으로 생각하고 있었다. 본 논문은 경영자가 우선적으로 관심을 두고 개선하여야 하는 부분과 경쟁력 확보를 위해 추가적으로 투자해야 할 부분이 어디인가에 대한 시사점을 제공해 준다는 점에서 연구의 의의가 있다.

• Journal of Plant Biology
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• 제9권1_2호
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• pp.7-16
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• 1966

In order to determine the factors related to site quality, 13 areas of Larch growing in the Kwangung and its vicinity forest as sample plots, were examined. Sample plots included various site classes as well as age classes. Three were divided into two groups (major and minor trees). Average height of dominant trees was determined through messurement of 5 to 6 dominant tree in each sample plots. Average height of dominant 30 year-old trees was the basis for site index. A Standard Yield Table for the larch produced in Kwangnung forest was made by various data, which included age class 5, ranging from 10 to 45 years. The relationship of the height of the trees, the site conditions, and ground vegetation are investigated in this paper. The site indexes of 40 forest class age in 28-B and 28-G forest classes of the larch associations for ground vegetation had comparatively rarge differences due to the sampled areas. The relation of the direction of forest communities to the height and the diameter of the tree shwoed that its communiteis of northest and northwest parts appeared higher valueof the height and the diameter. The diameter and the height of trees were closely realted to each other. The samller the occupied area per tree and the smaller the average distance among trees, the more density was increased. The larger the density was the lower height of the trees. In the ground vegetation of the larch communities, there seems to be a definite correlation between the height of trees and the occupied area per tree or the average distance among the trees. The height of trees and site index of two larch communities were as follow: 28-B forest class site index 20.8, height 24.0m, 28-G forest class site index 18.4, height 20.9m. The ground layer was analyzed by the method of Quadrat(20/20sq. cm) with an interval of 1M. It set up 40 Quadrats of the larch communiteis. The community structure of the ground vegetation of two larch was analyzed, and important value was calculated and then evaluated. The ground vegetation under the larch had developed Burmannii Beauv stratal society below the 28-B and 28-G the forest class. Accordingly, the first important value of Burmannii Beauv was found in two ground vegetation below the larch. Therefore, this species could be quantitatively considered as the forest indicator species. Common species of each community appeared 18 species out of 34 species in the ground vegetation under two larch communities. The ground vegetation of the 28-B forest class showed more than that of the 28-G forest class. the similarity of the ground vegetation was measrued by the Frequency Index Community Coefficient. The differences between the associations were lcearly manifested by the ground vegetation tested by Gleason's Frequency Index of Community Coefficient for the analysis of each stratal society of all associations. According to F.I.C.C. the ground vegetation under two larch(28-B and 28-G) forest classes showed higher value. An investigation into the relationship of physical and chemical properties of soil and site was considered the next step to be taken in the study of the larch site classification.

• Spatial Information Research
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• 제8권1호
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• pp.155-170
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• 2000

공간 인덱스인 R-Tree를 이용하여 조건에 만족하는 공간 객체를 찾기 위해서 MBR의 비교하는 여과 과정만으로는 부정확한 경우가 있으며 그러한 경우에는 해당 공간 객체를 읽어 조건과 직접 비교하는 과정, 즉 정제과정이 필요하게 된다. 정제과정을 수행하기 위해서는 디스크 입출력이 요구되고 고비용 공간 연상을 수행해야 하므로 이는 검색 비용이 커지는 요인이 된다. 그래서, 여과 과정후의 후보 객체수를 최소화하기 위한 2단계 여과 기법들이 연구되었지만, 여과 효율이 떨어지거나, 추가로 데이터를 유지해야하거나, 원래 객체의 정보를 잃어버려 객체들을 재구성해야하는 문제점이 발생한다. 따라서, 본 논문에서는 이차 여과 과정에서 공간 객체의 존재여부를 저장하는 진위 테이블인 그리드 필터를 이용하여 간단한 논리 연산만으로 공간객체를 검색할 수 있도록 하는 확장된 R-Tree를 제안한다. 그러므로, 그리드 필터를 가지는 확장된 R-Tree 는 효율적인 이차 여과과정을 수행하기 때문에 여과를 위한 연산비용이 작고, 근사의 질이 높아 여과 효율이 우수하다.

• 대한지역사회영양학회지
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• 제19권3호
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• pp.274-282
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• 2014

Objectives: The objective of this study was to revise the target pattern in food guidance system for adolescents' balanced menu planning. Methods: The food groups in the target pattern were divided into detailed food items, and intake number were assigned to each food items based on the revised standard food composition table. The validity of revised target pattern was examined. Menu planning according to the revised target pattern was made available to 305 male and female middle school students and the nutritional assessment of the menu plan were carried out using SPSS WIN 12.0. Results: The energy contents, energy contribution ratios of carbohydrate, fat, and protein, and 4 minerals' and 6 vitamins' contents of the revised target pattern were adequate. The average energy contents of the menu planned according to revised target pattern were 400~500 kcal higher than that of the revised target pattern when the revised standard food composition was applied. The energy contribution ratios of fat were 28.9%, close to maximum of acceptable macronutrient distribution range (AMDR) (30%), and that of carbohydrate were 54.5%, lower than minimum of AMDR (55%). The nutrient adequacy ratios (NARs) of calcium and vitamin C were less than 1.0. According to index of nutritional quality (INQ) of food items, kimchi, milk dairy products, and soybean curd were energy efficient source for calcium, kimchi, fruit, vegetable and seaweed were energy efficient source for vitamin C, with INQ of food items were higher or close to 2.0. Kimchi was the best energy efficient source of calcium and vitamin C. Conclusions: Revised target pattern based on the adolescent's foods intake was not good enough for balanced menu planning by adolescents, because what they ate and what they wanted to eat were very much different. Detailed guidance for food selection is necessary in each food items.

• 대한임상검사과학회지
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• 제36권1호
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• pp.19-26
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• 2004

According to increase of domestic blood components use, the quality control of blood components is necessary to support good products. The purpose of this study is used to provide the producing index of the good product as compared with the accuracy and validity for the distribution of the quality control data. The value of mean, standard deviation, 95% confidence interval and degree of normal distribution of data were calculated by univariate procedure, the value of monthly mean of each blood centers per items were compared by Analysis of Variance(ANOVA) test for the degree of distribution. When there was difference among the mean values, the Duncan's multiple range test was done to confirm the difference. Finally, methods for accessing accuracy and validity of the quality data was done by the Contingency table test. The quality data of five blood centers was showed to the normal distribution and it was in a acceptable range. For each blood centers, the monthly means of Hematocrit(Hct), Platelet(PLT) and pH were not significantly different except Hct of C center, PLT of B, D center and pH of A center. The quality data per items was graded according to quality to six level. As a result of the comparative analysis, the monthly means of Hct of C and E center was significantly different higher than that of D, B and A center. The monthly means of PLT of A center and pH of C center was significantly different higher than that of the others. In the accuracy and validity of the quality control data, C center for Hct, A center for PLT and C center for pH were better than the other. The C blood center was most satisfiable and stable in the quality control for blood component. If the quality control method used in C blood center is adopted in other blood centers, the prepared level of the blood component of the center will be improved partly.

• 디지털융복합연구
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• 제12권5호
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• pp.125-130
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• 2014

오늘날의 글로벌 시장에서의 경쟁은 많은 회사들이 시장에서 충분한 다양성을 가진 product family를 개발하도록 하고 있다. Product family를 설계할 때 중요한 이슈 중에 하나는 제품의 공통성과 차별성간의 절충점을 찾아내는 것이다, 이와 동시에 Product family를 설계할 때 리드타임을 단축시키고, 품질을 향상시키며 비용을 절감하는 것뿐만 아니라 제품의 환경 성능을 고려하는 것도 필요하다. 본 연구에서는 환경성을 고려한 메타 휴리스틱 알고리즘 기반의 그린 Product Family 재설계 방법론을 제안한다. 제안하는 방법은 그린 product family의 설계를 위해 메타휴리스틱 알고리즘으로써 유전자 알고리즘과 green product family index (GPFI)를 이용한다. 추가적으로 product family 레벨과 부품 레벨의 product family 재설계 추천방안도 제시하였다. 본 연구에서는 테이블 램프 product family를 대상으로 제안한 방법의 효율성과 타당성을 검증하였다.