• Title/Summary/Keyword: Clark

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A NUMERICAL STUDY ON THE EFFECT OF DOWN-WASH OF A WING-BODY ON ITS AERODYNAMIC CHARACTERISTICS (익형 동체의 하강기류(Down-wash)가 공기역학적 특성에 미치는 영향에 관한 수치해석연구)

  • Yoon, K.H.;Kim, C.H.
    • Journal of computational fluids engineering
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    • v.18 no.3
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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.

Grazing Soybean to Increase Voluntary Cow Traffic in a Pasture-based Automatic Milking System

  • Clark, C.E.F.;Horadagoda, A.;Kerrisk, K.L.;Scott, V.;Islam, M.R.;Kaur, R.;Garcia, S.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.3
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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.

Modelling Pasture-based Automatic Milking System Herds: Grazeable Forage Options

  • Islam, M.R.;Garcia, S.C.;Clark, C.E.F.;Kerrisk, K.L.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.5
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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.

Survival Association and Cell Cycle Effects of B7H3 in Neuroblastoma

  • Zhang, Haibo;Zhang, Jinsen;Li, Chunjie;Xu, Hao;Dong, Rui;Chen, Clark C.;Hua, Wei
    • Journal of Korean Neurosurgical Society
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    • v.63 no.6
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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.

Runoff Characteristics Analysis using GCUH on Ungauged Small Basin (지형기후학적순간단위유량도를 이용한 미계측 소유역의 유출특성 분석)

  • Lee, Sang-Jin;Choi, Hyun;Lee, Bae-Sung;Jeong, Dong-Kug
    • Journal of Korean Society for Geospatial Information Science
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    • v.14 no.2 s.36
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    • pp.15-22
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    • 2006
  • Runoff Characteristics has been Analysis Using geomorphologic Instantaneous Unit Hydrograph(GIUH) and geomorphoclimatic unit hydrograph(GCUH) on an ungaged vary small basin about $5km^2$ scale in Kyungbuk gampo area. First, we estimated hydrology Factor using Geographic Information System(GIS) tool and then, calculated the characteristic velocity using the real rainfall-runoff data. It is compared with several velocities derived from GCUH theory and several other concentration time formulae. Kerby and Braby-Williams seems to be more applicable as characteristic velocity formula. Second, We compared the GCUH peak discharge with the probable flood, also compared the unit hydrograph as like the Clark, the Nakayasu and the S.C.S and GCUH with the observed discharge using the real rainfall events. The comparison results showed that GCUH could be applicable on an ungaged vary small basin. We expected that the result can be used as for estimation of a flash flood standard rainfall as well as emergency management plan.

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Anti-ageing Effect of Cysteine-containing Peptides Derived from Milk Whey Protein (유청 유래 시스테인 함유 펩타이드의 항노화효과)

  • Dudek, Steffi;Clark, David C.
    • 한국유가공학회:학술대회논문집
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    • 2005.06a
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    • pp.13-35
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    • 2005
  • The trend towards ageing populations has been observed over many years in Europe and the US but has accelerated significantly in developed countries in Asia including Japan and South Korea. In the latter country the elderly population (65+) has increased 5-fold between 1960 and 2000 and this group will comprise 40% of the population by 2050. This creates a new socio-economic group with specific demands and considerable spending power. As ageing occurs a range of changes occur in the body that can be moderated by adjustments in nutrition. A significant body of evidence points to changes in the balance of glutathione synthesis and utilisation as people age. Glutathione is the most important natural anti-oxidant of the body and the amounts present can become limited by available cysteine in the diet. A cysteine-enriched peptide product, Cysteine Peption$^{TM}$ has been developed by DMV International for dietary supplement and food applications. A qualitative consumer trial has indicated benefits including improved sleep and more energy. Animal and clinical trials will be described that provide indications on bioavailability and possible mechanisms of action of Cysteine Peption$^{TM}$ with particular focus on the ageing population.

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CHANGE DETECTION ANALYSIS OF FORESTED AREA IN THE TRANSITION ZONE AT HUSTAI NATIONAL PARK, CENTRAL MONGOLIA

  • Bayarsaikhan, Uudus;Boldgiv, Bazartseren;Kim, Kyung-Ryul;Park, Kyeng-Ae
    • Proceedings of the KSRS Conference
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    • 2007.10a
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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.

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The Symbolistic Values of Western Beards' Style in the Twentieth Century (20세기 서구 남성 수염 스타일의 상징적 가치)

  • Chang, Mee-Sook;Lee, Hwa-Soon;Lee, Yon-Hee
    • Fashion & Textile Research Journal
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    • v.12 no.1
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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.

Effects of Strengthening and Stretching Exercise for Individuals with Intrinsic Patellofemoral Pain Syndrome (잠재적인 슬개대퇴동통증후군에 대한 근력 및 유연성운동의 효과)

  • Kim, Myung-Chul;Lee, Myoung-Hee;Han, Seul-Ki;Kim, Yong-Seong
    • Journal of the Korean Society of Physical Medicine
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    • v.6 no.2
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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.

AN ANALYSIS OF INFRARED IMAGES OF JUPITER IMPACTED BY P/SHOEMAKER-LEVY 9

  • KIM YONG HA;SUNG KIYUN;KIM SANG JOON;COCHRAN W. D.;LESTER D. F.;TRAFTON L.;CLARK B. E.
    • Journal of The Korean Astronomical Society
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    • v.29 no.2
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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.

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