• 한국세라믹학회지
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• 제27권3호
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• pp.311-320
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• 1990

Hydroxyapatite powders were synthesized with Ca/P=1.67, 1.70 and pH=7, 11 by precipitation method and fluorine substituted hydroxyapatite ceramics were prepared using these powders. After characterization of these hydorxyapatite bioceramics, chemical bonding between these sepcimens in simulated body fluid was investigated. Bysubstitution of 7.5% of fluorine, hydroxyapatite was prevented to decompose into β-tricalcium phosphate and its sintered density and mechanical strength were increased. The bending strength of these hydroxyapatite ceramics was 137MPa. The hydroxyapatite ceramics chemically bonded each other in Ringer's solution and the component of bonded layer was also hydroxyapatite.

• 동력기계공학회지
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• 제17권2호
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• pp.103-107
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• 2013

The structure of a variable liquid column oscillator(a VLCO) is analogous to that of the tuned liquid column damper used to suppress oscillatory motion in large structures like tall buildings and cargo ships. The VLCO is a system absorbing high kinetic energy of accelerated motions of multiple floating bodies in the effect of air springs occurred by installation of inner air chambers. Thus, VLCO can improve the efficiency of energy than wave energy converters of the activating object type made in Pelamis Company. In this research, the experiment was performed that a simple floating body was filled with internal fluid of same draft. The characteristics of motions were evaluated in each case of the opening or closing of the upper valves.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2011년 춘계학술대회논문집
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• pp.453-457
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• 2011

In this study, transonic aeroelastic response analyses haw been conducted for the business jet aircraft configuration considering shockwave and flow separation effects. The developed fluid-structure coupled analysis system is applied for aeroelastic computations combining computational structural dynamics(CSD), finite element method(FEM) and computational fluid dynamics(CFD) in the time domain. It can give very accurate and useful engineering data on the structural dynamic design of advanced flight vehicles. For the nonlinear unsteady aerodynamics in high transonic flow region, Navier-Stokes equations using the structured grid system have been applied to wing-body configurations. In transonic flight region, the characteristics of static and dynamic aeroelastic responses have been investigated for a typical wing-body configuration model. Also, it is typically shown that the current computation approach can yield realistic and practical results for aircraft design and test engineers.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.597-600
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• 2008

Preconditioners for a two-dimensional combined finite element formulation have been devised and tested for fluid-structure interaction (FSI) problems. The FSI code simulating the interaction of a elastic body with an unsteady flow is based on P2P1 finite element combined formulation. It has been shown that two preconditioners among them perform well with respect to computational memory and convergence for a bench-mark problem. Based on the verification of the preconditioners for the two-dimensional combined formulation, four preconditioners are proposed for the problem of an elastic body interacting with a flow.

• 대한한의학원전학회지
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• 제21권2호
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• pp.145-150
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• 2008

In this study, we investigated how prescriptions from "Sanghallon(傷寒論)", such as Oryeongsan(五笭散), Banhasasimtang(半夏瀉心湯), Dohaekseunggitang(桃核承氣湯), Jukyeopseokgotang(竹葉石膏湯), were applicated in Onbyeongjobyeon(溫病條辦). When applying prescriptions from "Sanghallon" onto Onbyeong(溫病), Odang had replaced warm, dry herbs with cool herbs which generate body fluid, considering general characteristics of onbyeong that may easily dry up and injure body fluid. In the case of Seuponbyeong(濕溫病), however, warm, dry herbs were also used, as well. Odang did not persist in the general characteristic of onbyeong, but composed prescriptions only based on pathological condition. From this, one can point out his precise thinking of Byeonjeung(辯證), and pragmatic nature of his study.

• Childhood Kidney Diseases
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• 제11권2호
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• pp.145-151
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• 2007

Hypertonicity (hypernatremia) of extracellular fluid causes water movement out of cells, while hypotonicity(hyponatremia) causes water movement into cells, resulting in cellular shrinkage or cellular swelling, respectively. In most part of the body, the osmolality of extracellular fluid is maintained within narrow range($285-295 mOsm/kgH_2O$) and some deviations from this range are not problematic in most tissue of the body except brain. On the other hand, the osmolality in the human renal medulla fluctuates between 50 and $1,200 mOsm/kgH_2O$ in the process of urine dilution and concentration. The adaptation of renal medullary cells to the wide fluctuations in extracellular tonicity is crucial for the cell survival. This review will summarize the mechanisms of urine concentration and the adaptation of renal medullary cells to the hyper tonicity, which is mediated by TonEBP transcription factor and its target gene products(UT-A1 urea transporter etc.).

• 한국식품영양학회지
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• 제8권2호
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• pp.110-115
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• 1995

This study was devised to observe the inhibitory effects of ethanol treatment precipitate (crude acidic polysaccharide) from Korean red ginseng on a lipolytic action of Toxohormone-L which has been known as lipolytic and anorexigenic factors. Toxohormone-L was obtained by partial purification of the ascites fluid from mice which had been inoculated with sarcoma-180. The yields of crude acidic polysaccharide from Korean red ginseng was 63.5%. In vitro, at the concentration of 500rg /ml, the inhibition rate of lipolysis by the crude acidic polysaccharide of Korean red ginseng was 38.8% and the total inhibitory activity per gram of ginseng material was 4,928 nit. In vivo, the red ginseng polysaccharide(40mg/ml in saline soon.) 16ul/g of body weight was injected to the sarcoma-180 bearing mice once In 3 days until death. The effects against the extension of life span was little but body weight gain of sarcoma-180 bearing mice decreased significantly by administration of Korean red ginseng polysaccharide compared to those of the control group.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1089-1090
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• 2006

Biomimetic apatite deposition behaviors on Zr-1Nb and Ti-6Al-4V plate with various surface conditions were examined. Both alloys were polished with abrasive papers to have different roughness and some of them were treated in NaOH before exposition in simulated body fluid. NaOH treatment was found to enhance the deposition rate of apatite on Ti-6Al-4V significantly. On the other hand, the deposition rate of Zr-1Nb was not influenced by NaOH treatment. Without NaOH treatment, the polished Zr-1Nb with abrasive paper was found to induce more apatite nucleation than the polished Zr-6Al-4V.

• 유공압시스템학회논문집
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• 제7권4호
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• pp.44-49
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• 2010

This paper represents solenoid design of control valve for incline angle control in variable compressor. Some theoretical and numerical analysis were performed to analyse solenoid and compared with experimental results. Maxwell program was used for numerical analysis. Through redesigns of housing body, plunger, core, and disk in control valve, the needed force was gotten. Reduction of core groove and housing body air-gap had a large influence on magnetic force. But increasing of disk thickness had little effect on magnetic force. Control valve efficiency could be improved through solenoid redesign.

• 한국가축번식학회지
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• 제16권2호
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• pp.165-173
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• 1992

In order to study the mechanism of follicle growth and maturation, and also to supplement the criteria identifying the follicle state of normal of atretic, the histochemical investigation on the ovarian follicles according to the ovarian cycle of mouse, rat and pig has been done. The intercellular space of granulosa cells, especailly Call-Exner body, and follicular fluid in the antrum showed positive to PAS, and blue stain by trichrome dye. The resutls suggest that the mucous polysaccharide was synthesized by the granulosa cells, and secreted into the antrum through Call-Exner body so as to be the components of the follicular fluid as the follicles proceeded to growth and maturation. The further the follicles proceeded to atresia the more densely their theca externa were stained blue by follicles proceeded to atresia the more densely their theca externa were stained blue by trichrome dye, and the more densely the granulosa cells were stained red by oil red 0 dye. Therefore, these staining methods can be applied to the criteria identifying the follicle atresia.