• 대한조선학회지
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• 제24권4호
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• pp.1-8
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• 1987

In this paper negative drift forces are discussed, which act on a two-dimensional cylinder exposed to slightly modulated waves in water of finite depth. By combining matched asymptotic expansion method with multiple scale technique, it is clearly shown that the slowly-varying drift force can be negative under certain circumstances: i) Incident waves are irregular or slightly modulated. ii) The water depth is finite compared to the wave length of carrier waves. iii) The gap between the keel of the cylinder and ocean floor is narrow. Then the negative drift forces are caused by the unbalance of hydrostatic force associated with set down. Real fluid and wave breaking effects are not considered.

• Bulletin of the Korean Chemical Society
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• 제17권12호
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• pp.1112-1117
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• 1996

The electronic structures of twenty-seven isomers of a macrocyclic fulleropyrrolidine are investigated with semi-empirical extended Huckel (EH) molecular orbital method. The geometry of each isomer is determined by the molecular mechanics and dynamics methods based on UFF (universal force field) empirical force field. The calculated geometries, such as the carbon-carbon distances of the fullerene moiety, are in good agreement with those of related fullerene derivatives. The EH calculation shows that the formation of macrocyclic pyrrolidine ring on fullerene moiety results in the reduction of the HOMO-LUMO energy gap. From the graphical analysis of the DOS (density of states), PDOS (projected DOS), and MOOP (molecular orbital overlap population) curves, we can find that this reduction is due to splitting of the HOMO of fullerene moiety, which results from the symmetry-breaking and the distortion of the buckminsterfullerene framework from its ideal icosahedral structure.

• 한국운동역학회지
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• 제21권2호
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• pp.161-171
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• 2011

The purpose of this study was to identify biomechanical characteristics of glide and delivery motion of In-Sung Hwang, player who is a member of the national team among the finalists in the men's shot put at the 2010 National Sports Festivals. Three-Dimensional motion analysis using a system of 3 video cameras at a sampling frequency of 60 Hz was performed for this study. During the glide and delivery phase the results showed following characteristics; 1) The glide type was suitable for the short-long technique, but the trajectory of shot at the glide and delivery phase showed a different trajectory pattern with "S-shaped" type of elite players due to many deviating from central axis of the APSS(athletic-plus shot system). 2) Left knee was more flexed during failed trials compared to successful trials but COG was higher. Therefore, the player showed less stability of COG as he may not get enough breaking force at the left foot. 3) Furthermore, it would be required to have strong muscle power at the trunk, throwing arm, and the lower extremity in order to achieve maintain a low projection angle of the release.

• Journal of Nutrition and Health
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• 제44권2호
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• pp.101-111
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• 2011

It is controversial whether low calcium intake, commonly associated with osteoporosis, results in calcium accumulation in soft tissues. This study was conducted to investigate the effects of low calcium (Ca) and oxalate (ox) intake on soft-tissue Ca deposits and bone metabolism in ovariectomized (ovx) rats. Eight week old female Sprague-Dawley rats were ovariectomized and divided into four groups. The rats were fed experimental diets containing low (0.1%, w/w) or normal (0.5%, w/w) Ca with or without sodium oxalate (1%, w/w); Sham/NCa, Ovx/NCa, Ovx/LCa, Ovx/NCa-ox, Ovx/LCa-ox for 6 weeks. All ovx rats showed a remarkable increase in body and tissue weight, glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, blood urea nitrogen, alkaline phosphatase, and decreases in weight, ash, and Ca contents, as well as bone breaking force compared to those in sham rats. Serum Ca concentration was not significantly affected by dietary Ca levels or ox intake. Kidney Ca, ox acid content, and microscopic Ca deposition increased remarkably in the Ovx/LCa-ox group compared to those in the other groups. Ca content in the spleen and aorta also increased significantly, but the weight contents, Ca, bone breaking force, and Ca and oxalic acid in feces decreased significantly in the Ovx/LCa-ox group. Serum parathyroid hormone levels were not significantly different among the groups. These results indicate that low Ca intake decreased bone mineral content and increased Ca deposits in soft tissues, which was aggravated by ox intake in ovx rats. Thus, high ox intake may result in a kidney disorder in patients with osteoporosis who eat a low Ca diet.

• 한국수산과학회지
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• 제32권3호
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• pp.247-251
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• 1999

최근 다양한 기능성의 발현으로 크게 각광받고 있는 키토산 올리고당을 이용하여 칼슘의 체내 흡수율의 효과에 미치는 영향을 in vitro 및 랫트를 이용한 in vivo에 의해 검토하였다. 1. 제조된 키토산 올리고당은 3당류$\~$5당류가 주로 분포되어 있었으며, 이들의 총 함량은 $70\%$ 이상이었다. 그리고 강력한 항종양활성 및 항균활성을 가지는 것으로 알려져 있는 6당류와 7당류도 각각 $14.2\%$와 $11.3\%$로 비교적 높게 함유되어 있었다. 2. in vitro에서, 키토산 올리고당의 첨가는 무첨가에 비해 칼슘의 흡수율을 약 $50\%$ 향상시킨 것으로 나타났다. 3. 키토산 올리고당 $1\%$만을 염화칼슘과 함께 랫트에 섭취시켰을 경우, 분으로 배출되는 칼슘량은 약 $75\%$ 감소하였으며, 대퇴골의 뼈골절강도는 대조군보다 약 $20\%$, 올리고당 무첨가군보다 약 $15\%$ 증가하였다. 4. 이상의 결과를 종합적으로 검토하면, 키토산 올리고당은 칼슘의 체내 흡수율을 명확히 향상시키는 것으로 판단되었다.

• 한국식품과학회지
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• 제30권6호
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• pp.1301-1306
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• 1998

산성, 중성 및 알칼리성 영역에서 각각 추출한 SPI를 첨가한 복합분의 제면적성에 미치는 영향을 조사하였다. SPI-건면과 조리면의 l값은 대조구에 비해 모두 감호하였으나 a와 b값은 증가하였다. SPI-건면의 최적조리시간은 100% 밀가루로 제조된 건면에 비해 증가하였으나 SPI-조리면의 중량, 부피 및 수분흡수율은 감소하였다. $SPI-2,\;SPI_3,\;SPI_7$및 $SPI-{10}$-건면의 파쇄력은 첨가농도에 관계없이 대조구에 비해 낮게 나타났으나 5%, 10% $SPI-{12}$-건면의 파쇄력은 대조구와 큰 차이를 나타내지 않았다. SPI의 첨가농도와 종류에 관계없이 SPI-조리면의 탄성과 응집성은 대조구와 비슷한 값을 나타내었고 씹힘성과 견고성은 대조구보다 높게 나타났다.

• Journal of Nutrition and Health
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• 제34권5호
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• pp.541-546
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• 2001

This study examined the effect of various types of exercise on bone formation and resorption in rat. Five-week-old male Sprague-Daweley rats were randomly assigned to one of four groups with 10 animals in each; Control, Treadmill, Swimming, Resistance. The exercise regimen consisted of treadmill running at 25m/min, 1 hr per day, 5 days a week, and swimming for 1 hr per day, 5 days a week. Resistant exercise type with weight-bearing was designed to extend lower and upper extremities in order to feed the diet and water. Food intake showed no significant difference among groups but body weight gain and food efficiency were significantly increased in Control group as compared with exercise groups. Femur and tibia length and weight were higher in Control group and the density of therm tended to be higher in exercise groups than Control group, but this difference was not statistically significant. The breaking force of femur was the highest in Swimming group and tibia was the highest in Resistance group among groups, while there was no signigicant difference among the exercise groups. The calcium content of femur was significantly increased in Resistance group than the other groups. Calcium intake and urinary calcium showed no significant difference among groups, while calcium absorption and retention were significantly higher in exercise group than Control group. In conclusion, exercise training enhanced bone formation due to the positive effect on metabolism of calcium and bone which were different according to the types of exercise. (Korean J Nutrition 34(5) : 541∼546, 2001)

• 대한조선학회논문집
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• 제49권6호
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• pp.478-483
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• 2012

The speed performances of ice sea trial on the Arctic(2010 & 2011) area were shown different results depend on the ice floe size. Penetration phenomena of level ice was not happened on medium ice floe and tore up by the impact force because the mass of medium ice floe is similar to the mass of Araon which is Korean ice breaking research vessel and did not shut up by the ice ridge or iceberg. The sea trial on the Amundsen sea was performed at the big floe which is classified by WMO(World Meteorological Organization). Three measurements of ice properties and five results of speed trial were obtained with different ice thicknesses and engine powers. To evaluate speed of level ice trial and model test results at the same ice thickness and engine power, the correction method of HSVA(Hamburg Ship Model Basin) was used. The thickness, snow effect, flexural strength and friction coefficient were corrected to compare the speed of sea trial. The analyzed speed at 1.03m thickness of big floe was 5.85 knots at 10MW power and it's 6.10 knots at 1.0m ice thickness and the same power. It's bigger than the results of level ice because big floe was also slightly tore up by the impact force of vessel based on the observation of recorded video.

• 생명과학회지
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• 제17권5호
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• pp.728-734
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• 2007

원료육(돈육 뒷다리 및 닭가슴살)에 따라 pH 조절법(3.0 또는 11.0)으로 제조한 수리미의 이화학적 및 관능적 특성을 비교 분석한 결과, 돈육 뒷다리를 활용한 pH 3.0으로 조절한 수리미는 높은 조단백질 함량, 수율, 보수력을 보였으나, 적색도, 황색도, Mb 및 metMb 함량이 높고(P<0.05) 백색도, 근원섬유단백질, 파괴강도, 변형값 및 겔강도가 낮아(P<0.05) 품질에 나쁜 영향을 미쳤다. 돈육 뒷다리를 활용한 pH 11.0으로 조절한 수리미는 높은 조직 특성과 낮은 Mb 및 metMb 함량으로 인해 양호한 결과를 얻었으나, 가열감량이 낮고 파괴강도, 변형값 및 겔강도가 낮게 나타났다(P<0.05). 또한 닭가슴살을 활용한 pH 3.0으로 조절한 수리미는 높은 조단백질 함량, 수율, pH, 파괴강도, 변형값, 겔강도 및 명도를 보여 양호한 결과를 얻었으나(P<0.05), 근원섬유단백질, 적색도 및 metMb 함량이 높고 수리미의 조직 특성이 낮아 품질에 나쁜 영향을 미쳤다(P<0.05). 닭가슴살을 활용한 pH 11.0으로 조절한 수리미는 근원섬유단백질, 변형 값, 명도, 백색도 및 응집성이 높고 Mb 함량, 가열감량, 조단백질 함량, 수율 및 파괴강도 값이 낮게 나타났다(P<0.05). 따라서 색 및 겔 특성을 기준으로 수리미의 품질 특성을 비교하면, 돈육 뒷다리에 비해 닭가슴살의 활용이 명도, 백색도, 파괴강도, 변형값 및 겔강도 값이 높게 나타났으며, pH 3.0에 비해 pH 11.0으로 회수한 수리미에서 높은 백색도, 근원섬유단백질 함량 및 응집성을 보였다. 그러나 모든 수리미 샘플의 관능평가 항목에서 유의적인 차이가 나타나지 않아, 돈육 뒷다리 및 닭가슴살을 활용한 pH 조절법으로 회수한 수리미의 제조가 가능할 것으로 판단된다..

• 문화기술의 융합
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• 제4권1호
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• pp.263-273
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• 2018

본 연구는 공시적 관점에서 광복이후부터 1960년대 태권도시범이 어떻게 이루어졌는지 규명하는데 목적 둔 문헌조사연구이다. 연구결과는 다음과 같다. 첫째, 광복과 기간도장의 태동, 한국군 베트남전 파병, 국제태권도연맹(ITF) 창설과 같은 사회상황은 태권도시범에 많은 영향을 주었다. 둘째, 태권도시범은 형식면에서 연무(硏武)시범형태로 각 도장에서 승급 심사나 관의 홍보 및 개인 수련기량 연마를 보여줄 때 행하는 것이었으며, 태권도 기본기술을 바탕으로 위력 손 발 격파, 단순 도약격파, 대련, 실전호신술과 같은 내용으로 이루어졌다.