• 한국전산유체공학회지
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• 제18권3호
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• pp.8-13
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• 2013

Drag reduction of a running vehicle is very important issue for the energy savings and emission reduction of its power train. Especially for a solar powered electric vehicle, the drag reduction and weight lightening are two serious problems to be solved to extend its driving distance under the given energy condition. In this study, the ground effect of an airfoil shaped road vehicle was studied for an optimum body design of an ultra-light solar powered electric vehicle. Clark-Y airfoil type was adopted to the body shape of the model vehicle to reduce aerodynamic drag. From the study, it was found that the drag of the model vehicle was reduced as the height(h) between ground and the lower surface of the model vehicle was decreased. It is due to the reduction of the down-wash decreasing the induced drag of the vehicle. The lift was also decreased as the height decreased. It is due to the turbulent boundary layer developed beneath the vehicle body. The drag is classified into two types; the form and friction drag. The fraction of form drag to friction one is 76 to 24 on the model vehicle. As the height(h) of the model vehicle from the ground surface increases the form drag also increases but the friction drag is in reverse.

• Asian-Australasian Journal of Animal Sciences
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• 제27권3호
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• pp.422-430
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• 2014

Pasture-based automatic milking systems (AMS) require cow traffic to enable cows to be milked. The interval between milkings can be manipulated by strategically allocating pasture. The current experiment investigated the effect of replacing an allocation of grazed pasture with grazed soybean (Glycine max) with the hypothesis that incorporating soybean would increase voluntary cow traffic and milk production. One hundred and eighty mixed age, primiparous and multiparous Holstein-Friesian/Illawarra cows were randomly assigned to two treatment groups (n = 90/group) with a $2{\times}2$ Latin square design. Each group was either offered treatments of kikuyu grass (Pennisetum clandestinum Hoach ex Chiov.) pasture (pasture) or soybean from 0900 h to 1500 h during the experimental period which consisted of 2 periods of 3 days following 5 days of training and adaptation in each period with groups crossing over treatments after the first period. The number of cows trafficking to each treatment was similar together with milk yield (mean ${\approx}18$ L/cow/d) in this experiment. For the cows that arrived at soybean or pasture there were significant differences in their behaviour and consequently the number of cows exiting each treatment paddock. There was greater cow traffic (more cows and sooner) exiting pasture allocations. Cows that arrived at soybean stayed on the allocation for 25% more time and ate more forage (8.5 kg/cow/d/allocation) relative to pasture (4.7 kg/cow/d/allocation). Pasture cows predominantly replaced eating time with rumination. These findings suggest that replacing pasture with alternative grazeable forages provides no additional incentive to increase voluntary cow traffic to an allocation of feed in AMS. This work highlights the opportunity to increase forage intakes in AMS through the incorporation of alternative forages.

• Asian-Australasian Journal of Animal Sciences
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• 제28권5호
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• pp.703-715
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• 2015

One of the challenges to increase milk production in a large pasture-based herd with an automatic milking system (AMS) is to grow forages within a 1- km radius, as increases in walking distance increases milking interval and reduces yield. The main objective of this study was to explore sustainable forage option technologies that can supply high amount of grazeable forages for AMS herds using the Agricultural Production Systems Simulator (APSIM) model. Three different basic simulation scenarios (with irrigation) were carried out using forage crops (namely maize, soybean and sorghum) for the spring-summer period. Subsequent crops in the three scenarios were forage rape over-sown with ryegrass. Each individual simulation was run using actual climatic records for the period from 1900 to 2010. Simulated highest forage yields in maize, soybean and sorghum- (each followed by forage rape-ryegrass) based rotations were 28.2, 22.9, and 19.3 t dry matter/ha, respectively. The simulations suggested that the irrigation requirement could increase by up to 18%, 16%, and 17% respectively in those rotations in El-Nino years compared to neutral years. On the other hand, irrigation requirement could increase by up to 25%, 23%, and 32% in maize, soybean and sorghum based rotations in El-Nino years compared to La-Nina years. However, irrigation requirement could decrease by up to 8%, 7%, and 13% in maize, soybean and sorghum based rotations in La-Nina years compared to neutral years. The major implication of this study is that APSIM models have potentials in devising preferred forage options to maximise grazeable forage yield which may create the opportunity to grow more forage in small areas around the AMS which in turn will minimise walking distance and milking interval and thus increase milk production. Our analyses also suggest that simulation analysis may provide decision support during climatic uncertainty.

• Journal of Korean Neurosurgical Society
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• 제63권6호
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• pp.707-716
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• 2020

Objective : The function of B7H3, a member of the B7 family of proteins, in neuroblastoma (NB) remains poorly characterized. Here we examine the expression pattern of B7H3 in clinical NB specimens and characterize the phenotype of B7H3 knock-down in NB cell line. Methods : Immunohistochemical (IHC) staining was carried out to assess the expression of B7H3 in clinical NB specimens. Survival association was analyzed using five Gene Expression Omnibus (GEO) datasets (GSE85047, GSE45480, GSE62564, GSE16476, GSE49710). Clonogenic survival and flow cytometry were performed after B7H3 knockdown to assess the cellular proliferation and cell survival in vitro. Impact of B7H3 silencing on NB growth was examined in vivo using the SH-SY5Y xenograft model. Results : On IHC staining, B7H3 was widely expressed in clinical NB specimens. Analysis of the transcriptional profiles of five GEO datasets clinically annotated NB specimens revealed that decreased B7H3 expression was associated with improved overall survival. B7H3 knockdown suppressed the proliferation of the SH-SY5Y NB model in vitro and in vivo. Cell cycle analysis revealed that B7H3 silencing induced G1/S arrest. This arrest was associated with the suppression of E2F1 expression and induction of Rb expression. Conclusion : Our results demonstrate that B7H3 expression correlate with clinical survival in NB patients. Preliminary studies suggest that B7H3 may mediate the G1/S transition.

• 대한공간정보학회지
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• 제14권2호
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• pp.15-22
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• 2006

지형학적순간단위유량도 및 지형기후학적단위유량도를 이용하여 미계측 소유역의 특성을 분석하였다. 경북 감포지역 $5km^2$ 미만의 소유역을 중심으로 GIS 기법으로 수문특성인자를 도출하고, 지형학적순간단위유량도의 동역학적 매개변수인 특성속도를 호우사상별로 추정하여 지형기후학적 순간단위유량도 및 기타 집중시간 경험식과 비교한 결과 Kerby 및 Brasby-Williams공식이 소유역의 특성속도 산정공식으로 제시될 수 있는 것으로 분석되었다. 또한 확률 강우량으로부터 지형기후학적순간단위유량도의 첨두유량과 확률홍수량을 비교하는 방법과 여러 단위유량도 및 지형기후학적순간단위유량도에서 산정된 첨두유량을 실측자료와 비교한 결과 미계측 소유역의 적용 타당성이 확인되어 향후 돌발홍수 등 방재계획 수립 시 기준우량을 산정하는데 활용될 수 있을 것으로 판단된다.

• 한국유가공학회:학술대회논문집
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• 한국유가공기술과학회 2005년도 창립 30주년 기념 국제심포지움 - 웰빙시대의 우유.유제품의 새로운 발견
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• pp.13-35
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• 2005

노인 인구 증가는 유럽과 미국에 걸쳐 몇 년간 관찰되어 왔지만, 일본과 한국과 같은 개발도상국에서도 증가 추세가 현저히 나타나고 있다. 개발도상국에서는 2000년, 65세 이상 노인의 인구비율이 1960년에 비해 약 5배 정도 증가했으며, 2050년에는 전체 인구의 40% 정도를 차지할 것으로 예상되고 있다. 이런 급격한 인구 변화는 이들이 특정 권리와 구매력을 지니는 새로운 사회경제적 집단으로 성장하게 하는 계기가 되었다. 노화가 일어나면, 식이요법으로 어느 정도 조절할 수 있는 인체의 변화가 다양하게 일어난다. 그 중 대표적인 것은 글루타치온 합성과 이용의 균형에 변화가 생기는 것이다. 글루타치온은 인체에서 가장 중요한 항산화 물질이고, 식이 내 시스테인 아미노산에 의해 체내 함량이 결정될 수 있다. 시스테인이 풍부한 펩티드 제품이 기능성 식품 및 식품원료로 개발되었다. 소비자 조사 결과, 이 제품은 숙면과 활력을 제공하는 등 장점이 있음이 밝혀졌다. 동물 임상 실험 결과를 통해 특별히 노인 인구를 대상으로 하여 시스테인 펩타이드의 생리 활성과 대사 과정을 소개하고자 한다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.426-429
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• 2007

One of the widely used applications of remote sensing studies is environmental change detection and biodiversity conservation. The study area Hustai Mountain is situated in the transition zone between the Siberian taiga forest and Central Mongolian arid steppe. Hustai National Park carries out one of several reintroduction programs of takhi (wild horse or Equus ferus przewalskii) from various zoos in the world and it represents one of a few textbook examples of successful reintroduction of an animal extinct in the wild. In this paper we describe the results of an analysis on the change of remaining forest area over the 7-year period since Hustai Mountain was designated as a protected area for reintroduction to wild horses. Today the forested area covers approximately 5% of the Hustai National Park, mostly the north-facing slopes above 1400 m altitude. Birch (Betula platyphylla) and aspen (Populus tremula) trees are predominant in the forest. We used Landsat ETM+ images from two different years and multi temporal MODIS NDVI data. Land types were determined by supervised classification methods (Maximum Likelihood algorithm) verified with ground-truthing data and the Land Change Modeler (LCM) which was developed by Clark Labs. Forested area was classified into three different land types, namely the forest land, mountain meadow and mountain steppe. The study results illustrate that the remaining birch forest has rapidly changed to fragmented forest land and to open areas. Underlying causes for such a rapid change during the 15-year period may be manifold. However, the responsible factors appear to be the drying off and outbreak of forest pest species (such as gypsy moth or Lymantria dispar) in the area.

• 한국의류산업학회지
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• 제12권1호
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• pp.21-30
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• 2010

The purpose of this study is to research the symbolistic values of western beards' style in the twentieth century. Namely, it is to consider the relationship between social-cultural factors and aesthetic meanings of western beards' style. The contents are, firstly, studying the conception and the types of beard. A beard is the hair that grows on a person's chin, cheeks, neck, and the area above the upper lip. At the World Beard & Moustache Championships, there are moustache category (natural, english, hungarian, dali, fu manchu, freestyle), beard category (natural, musketeer, goatee, sideburns, freestyle), and full beard category (natural, garibaldi, verdi, van dyck, freestyle), Secondly, this paper is continued by researching the history of beard from the ancient to the present day, and thirdly, analyzing political dictatorship, social resistance and expression of personality, religious dignity, related with the change of world situation, the formation of postmodern anti-culture and pop-culture, and the coexistence of traditional culture. There are long and bushy full beards in some religions like Hinduism, Judaism and Islam. The meanings of their beards are purity, life and holiness. The beards of some politicians symbolize dictatorship. Namely, the chaplin of Hitler, the moustache of Hussein and the musketeer of Castro express strong power and charisma. In 1950s'-70s' subcultures, Hipsters' goatee, Bikers' horseshoe, Beat generations' goatee and Hippies' natural represent the lack of adaptability and social resistance. Also, the celebrities and artists like Ronald Colman, Clark Gable, Don Johnson, George Clooney, and Salvador Dali express freedom, personality, and taste with beards. For that matter, the symbolistic values of beards' style in the twentieth century are the religious dignity, the political dictatorship, the social resistance and the expression of personality. Today the beards' style is one of fashion items as well as a symbol of masculinity, customs and classes.

• 대한물리의학회지
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• 제6권2호
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• pp.165-175
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• 2011

Purpose: This study examined the effect of the strengthening exercise and stretching exercise to decrease symptom patellofemoral pain syndrome (PFPS). Methods: The Anterior Knee Pain Scale (AKPS) and Clark's test performed for diagnosis of intrinsic PFPS among young adults. Selected thirty young adults subjects who aged 20~26 years participated in the study. Participants were randomly assigned to strengthening, stretching, or control groups. Strengthening group consisted of quadriceps, hamstring and iliotibia band training used elastic band. Stretching group consisted of quadriceps, hamstring and iliotibia band trainings used stretching exercises program. Participants received 50-minute individualized exercise sessions, 3 times a week for 6 weeks. Results: The results were as follow: there were significantly difference stretching exercise group by all muscles on muscular strength test (p<.05). there were significantly difference both strengthening and stretching exercise group by all muscles on flexibility test (p<.05). There were significantly difference stretching exercise group by all muscles on step-down test (p<.05). There were significantly difference both strengthening and stretching exercise group by all muscles on visual analog scale (p<.05). Conclusion: Results suggest important implications for exercise programs of PFPS that stretching exercise is more improved knee pain, functional performance, patella mobility than strengthening exercise.

• 천문학회지
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• 제29권2호
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• pp.245-253
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• 1996

We have analyzed infrared (IR) images of Jupiter which was observed at the McDonald Observatory, Texas, U.S.A., during the P/SHoemaker-LEvy 9 (SL9) impact period and about one week after the last impact. The IR images were obtained on the 2.7m telescope using a NICMOS array with filters to isolate the $1.5{\mu}m\;NH_3\; band,\;the\;2.3{\mu}m\;CH_4\;band,\;the\;2.12{\mu}m\;H_2\;S(0)$ pressure-induced absorption, and the continua at $1.58{\mu}m\;and\;2.0{\mu}m$ (short K-band). All images except those with the $1.58{\mu}m$ continuum filter show bright impact sites against the relatively dark Jovian disk near the impact latitude of about $45^{\circ}$ S. This implies that dusts originated from the impacts reflect the solar radiation at high altitudes before absorbed by stratospheric $CH_4,\;NH_3 \;or\;H_2$. The impact sites observed with the $2.3{\mu}m$ filter are conspicuously bright against a very dark background. The morphology of impact sites, G, L, and H at 2.3 and $2.12{\mu}m$ filters shows clearly an asymmetric structure toward the incident direction of the comet fragments, in agreement with the studies of visible impact images obtained with the Hubble Space Telescope. Comparisons of reflectances of G, L, and H sites with simple radiative transfer models suggest that optically thick dust layers were formed at high altitudes at which methane absorption attenuates incoming sunlight only by about $1\%$. The dust layers in these sites seem to form at about the same altitude regardless of the magnitude of the impacts, but they appear to descend gradually after the impacts. The dust layers have optical depths of 2-5, according to the models.