• KDI Journal of Economic Policy
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• 제36권4호
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• pp.1-32
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• 2014

주파수와 같이 매우 희소한 경제적 자원을 배분하는 경우 경매는 배분적 외부성으로 인하여 비효율적 결과를 낳을 수 있다. 경매수입이 아닌 사회후생을 기준으로 하면, 경매를 통한 배분은 경매참여자가 2인일 때에도 비효율적일 수 있다. 이는 2위 기업이 주파수를 더 효율적으로 활용할 수 있다 하더라도 이를 통해 얻는 이익은 크지 않은 반면에 선도기업이 시장을 잠식당함으로써 입는 손실이 클 때 발생한다. 2-경기자 호텔링 모형을 사용하여 분석한 결과, 2위 기업의 입찰가에 어떠한 승수를 곱함으로써 2위 기업을 경매에서 유리하게 만들 경우 경매를 통한 배분 결과가 파레토 개선된다. 승수는 시장점유율을 바탕으로 구할 수 있으며 시장점유율 격차가 클수록 높다.

• Preventive Nutrition and Food Science
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• 제8권3호
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• pp.289-293
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• 2003

Antioxidant activity and nicotine degradation activity (NDA) of 21 medicinal herbs were determined by using a 1,1-diphenol-2-picrylhydrazyl (DPPH) method and a PLC/PRF5 human liver cell line method, respectively, to develop an anti-smoking aid. The highest and lowest antioxidant activities represented by $IC_{50}$/ value were 30 $\mu$g/mL of Eugenia caryophyllus and 3,270 $\mu$g/mL of Panax ginseng C. A. Meyer, respectively. Antioxidant activity of Eugenia caryophyllus was equal to 38.0$\pm$1.2 mg VCEAC(vitamin C equivalent antioxidant capacity)/ g herb. The highest and lowest NDA values were 1.81 of Astrgalus membranaceus Bunge and 1.01 of Raphani seed and Lespedeza tomentosa Sieb, respectively. Eleven medicinal herbs with high antioxidant activity and/or NDA were selected to make an herbal tea. The herbal tea had high antioxidant activity (50 $\mu$g/mL $IC_{50}$/ and 22.4$\pm$1.4 mgVCEAC/g) and NDA (1.243). The medicinal herb tea could help smokers quitting smoking by degrading and exhausting nicotine accumulated in body and removing reactive oxygen species.

• Wind and Structures
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• 제11권3호
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• pp.193-208
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• 2008

This paper focuses on assessing the failure of one of the transmission towers that collapsed in Winnipeg, Canada, as a result of a microburst event. The study is conducted using a fluid-structure numerical model that was developed in-house. A major challenge in microburst-related problems is that the forces acting on a structure vary with the microburst parameters including the descending jet velocity, the diameter of the event and the relative location between the structure and the jet. The numerical model, which combines wind field data for microbursts together with a non-linear finite element formulation, is capable of predicting the progressive failure of a tower that initiates after one of its member reaches its capacity. The model is employed first to determine the microburst parameters that are likely to initiate failure of a number of critical members of the tower. Progressive failure analysis of the tower is then conducted by applying the loads associated with those critical configurations. The analysis predicts a collapse of the conductors cross-arm under a microburst reference velocity that is almost equal to the corresponding value for normal wind load that was used in the design of the structure. A similarity between the predicted modes of failure and the post event field observations was shown.

• Journal of Advanced Research in Ocean Engineering
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• 제1권4호
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• pp.227-238
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• 2015

The present work was an attempt to investigate the applicability of truncated mooring systems to KRISO's deep ocean engineering basin (DOEB) with ratios of 1:100, 1:60, and 1:50. The depth of the DOEB is 15 m. Therefore, the corresponding truncated depths for this study were equal to 1500 m, 900 m, and 750 m. The investigation focused on both the static and dynamic characteristics of the mooring system. It was shown, in a static pull-out test, that the restoring force of a FPSO vessel could be modified to a good level of agreement for all three truncation cases. However, when the radius of the mooring site was reduced according to the truncation factor, the surge motion response during a free-decay test showed a significant difference from the full-depth model. However, the reduction of this discrepancy was achieved by increasing the radius up to its maximum possible value while considering the size of the DOEB. Especially, in terms of the time period, the difference was reduced from 24.0 to 5.3 s for a truncation ratio of 1:100, 54.1 to 8.6 s for a truncation ratio of 1:60, and 31.7 to 3.9 s for a truncation ratio of 1:50. As a result, the study verified the applicability of the truncated mooring system to the DOEB, and therefore it could represent the full-depth mooring system relatively well in terms of the static and dynamic conditions.

• 치과방사선
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• 제28권1호
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• pp.47-58
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• 1998

The purpose of this study was to investigate an influence of the change of central panoramic curves on the image reconstruction in the dental implant CT. The author designed three experimental groups according to the location of central panoramic curve. In group A, central panoramic curve was determined as the curve connecting the center of roots from the first premolar to the first molar. In group B, central panoramic curve was determined as the line connecting the lingual cortical plate at the level of the mesial aspect of the first premolar with the buccal cortical plate at the level of the mesial aspect of the first molar. In Group C, central panoramic curve was determined as the line connecting the buccal cortical plate at the level of the mesial aspect of the first premolar with the lingual cortical plate at the level of the mesial aspect of the first molar. Twenty four reformatted CT images was acquired from four mandibles embedded in the resin block and twenty four contact radiographs of dog specimens were acquired. Each Image was processed under Adobe Photoshop program analysed by MSPA(mandible/maxilla shape pattern analysis) variables such as MXVD, MXHD, UHD, MHD, and LHD. The obtained results were as follows ; 1. The mean of MXVD variable was 19.9, 20.2, and 20.0 in group A, B, and C, respectively, which were smaller than actual value 20.5. But, there was no significant difference among 3 groups (p>0.05). 2. The mean of MXHD, UHD, MHD, and LHD variables in group A, B, and C was 11.9, 12.2, and 12.3; 9.3, 9.5, and 9.6; 10.0, 10.3, and 10.3; 9.2, 9.3, and 9.4 respectively which were equal to or greater than the actual value 11.8, 9.3, 10.0, and 9.2. But, there was no significant difference among 3 groups (p>0.05). 3. The number of noneffective observations with difference over or under 1 mm with comparison to the actual value was 24(20％), 58(48.3％), and 52(43.3％), respectively, in group A, B, and C. 4. In group A, the number of observations over 1 mm and under 1 mm was 9 and 15, respectively, but in group Band C, the number of observations over 1 mm was more than under 1 mm.

• Asian-Australasian Journal of Animal Sciences
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• 제22권5호
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• pp.694-699
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• 2009

The present study was conducted to evaluate the effect of chilled drinking water on the productivity of laying hens under constant high ambient temperature. A total of seventy-two, 123-day-old Hy-line brown layers was divided into two equal groups. The first group (UDWG) was given unchilled water ($23.0{\pm}2.5^{\circ}C$) as a control, and the second group (CDWG) was given chilled water ($16.0{\pm}0.5^{\circ}C$). The laying hens were kept at $30^{\circ}C$ constant temperature with 50% relative humidity and were exposed to 17 h of light per day. Feed intake, egg production, egg quality (egg weight, shell weight, shell thickness, egg color, yolk color, and Haugh unit), and blood samples were collected and analyzed. The results showed that the feed intake of CDWG laying hens was significantly higher (11.64%) than the UDWG counterparts (p<0.01). Egg production of CDWG was also significantly higher (11.27%) than the UDWG counterparts (p<0.001). Furthermore, we observed that the CDWG laying hens had significantly higher (11.72%) levels (p<0.10) of blood calcium, with a corresponding value of 21.92 mg/dl compared to the UDWG hens (19.62 mg/dl). The higher calcium concentration in the CDWG animals may contribute to increased egg production. The CDWG laying hens also contained higher (12.53%) phosphorus concentrations in blood compared to the UDWG (4.22 mg/dl vs. 3.75 mg/dl), although not statistically different (p>0.10). Egg weight and egg quality were not affected by chilled drinking water. In conclusion, providing chilled drinking for laying hens under high ambient temperature improved feed intake and egg production.

• 디자인학연구
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• 제15권4호
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• pp.359-368
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• 2002

본 연구는 시각적 등가성에 대한 한국인의 성향분석을 목적으로 수행되었다. 자연현상에서 흔히 조우할 수 있는 시각적 동등성에 우리가 동일한 가치를 부여할 수 있는지 없는지에 대해 일부 심리학자들의 유사연구를 참고로 하였고, 설문조사를 통해서 한국인의 성향을 조사하였다. 그 결과는 다음과 같은 발견점을 가져다 주었다. - 일부 특수한 경우를 제외하고 시각적 등가성은 한국인에 있어서는 현실적으로 존재하기 어렵다. - 화면에서의 대각선은 오른쪽 아래에서 왼쪽 위방향보다 왼쪽 아래에서 오른쪽 위방향으로 보다 상승감을 느끼게 해준다는 지적은 사실로 드러났다. - 화면의 오른쪽이 왼쪽보다 무거워보인다는 지적은 우리 나라 사람들에게 있어서는 확인되지 않았거나 무시할만한 정도 이내이다. - 자연현상의 묘사나 이에 대한 관찰자의 시각물 수용에서, 사용자 인터페이스가 작용하는 것으로 드러났다. 이 경우 오른손 듣기가 대부분인 한국인에 있어서는 이러한 현상을 자연스러운 것으로 받아들이는 것이 좋다. - 한국인의 좌측 우위사상에서 오는 전래적인 시각적 표현은 지금도 우리 문화 속에 녹아 있다. 이상의 내용을 한 마디로 정리한다면, 한국인에 있어서 시각적 등가성은 대체적으로 실존하지 않는다는 점이며, 여러 가지 측면에서 오른쪽보다는 왼쪽에 경도되는 일반적인 성향을 한국인이 가지고 있다는 점이 발견되었다.

• 조명전기설비학회논문지
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• 제23권10호
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• pp.14-20
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• 2009

전력 계통 내에서 발생하는 과도한 고장전류의 억제를 위한 가장 이상적인 방안은 초전도 한류기이다. 초전도 한류기의 전력계통 적용을 위해 본 논문에서는 전력계통 내에서 발생하는 1선, 2선, 3선 지락사고를 모의하여 매트릭스형 초전도 한류기의 동작 특성 및 소비전력을 분석하였다. 모든 지락사고에 대해 매트릭스형 초전도 한류기는 사고 초기에는 85[%] 이상, 1주기 이후에는 95[%] 이상 고장전류를 제한시킬 수 있다는 것을 확인하였다. 또한 초전도 소자간의 임계특성의 차이를 줄여줌으로써 소비전력이 균등해진다는 것을 확인하였다.

• 복식문화연구
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• 제13권6호통권59호
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• pp.960-976
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• 2005

Classicism pursued beauty comprised of a perfect form, and beauty was perceived as a state of sufficiency. Accordingly, a completed and permanent beauty was sought after; as a result, a perfect and flawless form became the mainstream, and there was an effort to visualize the eternal proportional perfection. In classicism, forms were perfectly embodied with systematic inevitability and absolute inflexibility, by which an extremely clear aspect appeared. This study analyzes a classical construction paradigm in modern fashion according to the five categories: 'Harmony and order by numerical proportion', 'Clear form', 'Simplification of form and two-dimensional Seh-form', 'Completed contracture structure', and 'Pluralistic unification', and the respective formative characteristics are as follows. First, in terms of the formative aspect of modern fashion,'Harmony and order by numerical proportion' results from thorough observance of extreme and golden section (proportion of 5 :8) which was an aesthetic standard of beautiful body in classicism. Second, 'Clear form' appears in clothes as individual clearness of structural elements expressing each part of body, and shows a well-established form possible to be grasped with equal and clear contour line. Third,'Simplification of form and two-dimensional Seh-form' comes out as form composition, single line, single layer structure, two-dimensional form and arrangement of elements of clothes through the front viewpoint caused by 2D diagramming work while fashion-designing and producing. Also, it is seen that two-dimensional proportion which is composed of sections through various harmonious lines and sides according to the simple two-dimensional compatibility principle is accomplished. Fourth, 'Completed contracture structure' emerges as an expression of stationariness, in other words, fixation of an overall impression. This is a tendency that the overall form is grasped as a fixedly intact shape without a big change of the silhouette of clothes. Fifth, 'Pluralistic unification' means that it respectively emphasizes all the parts composing clothes by making them individually independent at the same time as each element is inclusively shown with the harmony of the overall silhouette of clothes and many other details. This study examined classical formative characteristics through a theoretical research on a formative paradigm revealing the classical style. Also, the significance of classical or rational value of art was illuminated by observing what characteristics a classical formation paradigm shows in modern fashion. As a result, classical characteristics in modern fashion prove that classicism is not a merely past construction style separated from the present but a construction paradigm deeply involved in our reason system.

• Journal of Animal Science and Technology
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• 제62권3호
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• pp.374-384
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• 2020

Two experiments were conducted to determine apparent metabolizable energy (AME), nitrogen-corrected AME (AMEn), and ileal digestible amino acid (AA) content of brown rice (BR) and to investigate the effect of dietary supplementation of BR on laying performance and egg quality of laying hens. In Exp. 1, 72 Hy-line Brown layers (49-week-old) were allocated to two treatments using a completely randomized block design, and each treatment included six cages per treatment and six hens per cage. A semi-purified diet was formulated to include BR as the sole source of AA and energy and an N-free diet was used to determine basal endogenous loss of AA. The hens were fed a commercial layer diet for adaptation to the experimental environment and diet for 7 days from d 0, and then fed experimental diets for 5 days from d 7. Excreta were collected from d 10 to 11 and ileal digesta were collected on d 12. On a dry matter (DM) basis, the AME and AMEn of BR was determined at 3,773 and 3,729 kcal/kg, respectively. The apparent ileal digestibility (AID) of BR ranged from 32.7% for Thr to 73.7% for Arg. The range of the standardized ileal digestibility (SID) value was between 79.4% for Met and 96.6% for Lys. In Exp. 2, 252 Hy-line Brown layers (44-week-old) were divided into four groups, comprising seven replicates of nine birds each and assigned to four experimental diets containing 0 (Control), 5%, 10%, or 15% BR for 5 weeks. The BR-containing diets were formulated to be equal in the content of AMEn and digestible AA to those of the diet without BR. No significant differences were observed in laying performances. Egg quality and blood profiles were not linearly or quadratically affected by dietary treatments. These results suggest that up to 15% BR can be included into layer feed without any adverse effects on laying performance and egg quality, if its energy and digestible AA values are well evaluated.