• Elastomers and Composites
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• 제6권1호
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• pp.53-70
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• 1971

We have studied the blending effects of cis-1,4-polybutadiene (CBR) and styrene-tutadiene rubber at various blending ratios of 100 : 0, 70 30, 50 : 50, 30 : 70, 0 : 100, and of carbon black ISAF and HAP at various compounding ratios of 45 PHR, 55 PHR, 65 PHR, for tyre tread rubber. The results obtained are summerized as follows; 1. For tyre tread rubber, it was found to increased efficiency to use SBR polymer only than to use the blending ratio CB/SBR=30/70 below. But it was observed that the latter was adapted for the bus or truck tyre and the former for the passenger tyre. 2. Excellent efficiency was obtained in case of carbon black compounding ratio of 55%, and also the compounding of ISAF made better efficiency than that of HAF. 3. Carbon black was more efficient to SBR than to CB. 4. For the aging ratio, the compounding rubber of NR was the highest, and the ratio was decreased in order of the compounding rubber of oil-extended SBR or CB polymer only, the compounding rubber of non oil-extended SBR or CB polymer only, and the blending rubber.

• 한국자원식물학회지
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• 제20권6호
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• pp.491-498
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• 2007

It has been hypothesized that efficient exclusion of methylated retrotransposons and repeated DNA region is one of the rapid and cost-effective approaches for comprehensive gene discovery in large genome size of maize. Three kinds of methylation-sensitive restriction enzymes, HapII, MspI and McrBC, were used to identify the restriction frequency of cytosine methylation sites in maize genome. Roughly 60% of total maize genomic DNA was restricted less than 500bp by McrBC, and the most of restricted small size fraction was composed retrotransposon. In order to validate the efficient construction of gene-rich shotgun library, we compare two gene-rich methyl-filtration shotgun libraries using in vivo and in vitro methyl-filtration system. The size selected DNA fraction by Sau3A-McrBC enzyme treated was very stable and has not appeared modification in E. coli, but most insert DNA size of partially digested with Sau3A were decrease less than 500bp by bacterial methylation-modification system. In compare of retroelements portion, A 44.6% of the sequences were retroelement in unmethyl-filtered library, and the most of them was Copia type, such as Prem, Opie and Ji. The portion of retroelement was drastically decreased to 25% and 20% by in vivo and in vitro filtration system, respectively.

• 혜화의학회지
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• 제16권2호
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• pp.217-223
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• 2007

Over the period between October 2005 and February 2007, herbal medicine was administered to the patients coming to Dr. Cha Oriental Medical Clinic. As regards the prescription administered to children patients for treating their growth deficiency, Eukmigihwang-tang related to the kidney, the congenital factor, Bojungikgi-tang related to the spleen, the acquired factor. So I administered Eukmigihwang-tang plus Bojungikgi-tang(a union of both herb-remedy: Eukmigihwang-tang and Bojungikgi-tang) The results were obtained as follows. 1. The youngest is six years old, the oldest is thirteen years old. 2. A ratio of male and female children was same. 3. It was shown to be a greater increase than the average value of growth surveyed by the National Statistical Office. 4. It is considered that EukmigihwangtangHapBojungikgitang is effective on child growth.

• 한국재료학회지
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• 제19권12호
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• pp.680-685
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• 2009

Using a polyurethane foam replica method, porous hydroxyapatite scaffolds (PHS) were fabricated using conventional and microwave sintering techniques. The microstructure and material properties of the PHS, such as pore size, grain size, relative density and compressive strength, were investigated at different sintering temperatures and holding times to determine the optimal sintering conditions. There were interconnected pores whose sizes ranged between about 300 ${\mu}m$ and 700 ${\mu}m$. At a conventional sintering temperature of 1100$^{\circ}C$, the scaffold had a porous microstructure, which became denser and saw the occurrence of grain growth when the temperature was increased up to 1300$^{\circ}C$. In the case of microwave sintering, even at low sintering temperature and short holding time the microstructure was much denser and had smaller grains. As the holding time of the microwave sintering was increased, higher densification was observed and also the relative density and compressive strength increased. The compressive strength values of PHS were 2.3MPa and 1.8MPa when conventional and microwave sintering was applied at 1300$^{\circ}C$, respectively.

• 한국세라믹학회지
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• 제45권1호
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• pp.1-29
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• 2008

In last two decades, an impressive progress has been recorded in terms of developing new materials or refining existing material composition/microstructure in order to obtain better performance in biomedical applications. The success of such efforts clearly demands better understanding of various concepts, e.g. biocompatibility, host response, cell-biomaterial interaction. In this article, we review the fundamental understanding that is required with respect to biomaterials development, as well as various materials and their properties, which are relevant in applications, such as hard tissue replacement. A major emphasize has been placed to present various design aspects, in terms of materials processing, of ceramics and polymer based biocomposites, Among the bioceramic composites, the research results obtained with Hydroxyapatite (HAp)-based biomaterials with metallic (Ti) or ceramic (Mullite) reinforcements as well as $SiO_2-MgO-Al_2O_3-K_2O-B_2O_3-F$ glass ceramics and stabilized $ZrO_2$ based bioinert ceramics are summarized. The physical as well as tribological properties of Polyethylene (PE) based hybrid biocomposites are discussed to illustrate the concept on how can the physical/wear properties be enhanced along with biocompatibility due to combined addition of bioinert and bioactive ceramic to a bioinert polymeric matrix. The tribological and corrosion properties of some important orthopedic metallic alloys based on Ti or Co-Cr-Mo are also illustrated. At the close, the future perspective on orthopedic biomaterials development and some unresolved issues are presented.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 전력전자학술대회 논문집
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• pp.9-13
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• 2001

This paper proposes the electric stimulus tactile apparatus system(TESTAS) loaded on the hap-tic interface using ultrasonic motors(USMs). To touch the virtual object like wall in graphic, the 6 DOF haptic interface provides force feedback to users as if it is real. But the case of sharp virtual object like a puncture, it could not provided the sense of pain, but only the reaction-force. After the TESTAS had been loaded on this haptic interface. it could Provide not only the force but also the pain to users. To estimate the capability of TESTAS, we did experiments of three cases, one was very sharp, another was dull, the other is continuative contact.

• 대한의료기공학회지
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• 제5권1호
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• pp.22-39
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• 2001

This study is designed to compare the effect of a needle with the magnet on body. We took the skin temperature of the belly with digital infrared thermographic imaging while we sticked needle and apply magnets on L14. We made experiments on 40 healthy male volunteers for one month. We classified control group not acupuncture or magnet adhering(CON). acupuncture group on left and right L14(LA). and the permanent magnet group adhering to left and right(LM). And LM is divided into S-polar permanent magnet group(LMS) and N-polar permanent magnet group adhering to left and right L14(LMN). When we observed that temperature changed with time, the skin temperature of th belly in CON descended significantly but LM, LMS and LMN is not changed significantly. As mentioned above. we observed that the needles on L14 affected the change of temperature on the belly, and conjectured that the appliance of magnets had the same results. If the mechanism depends on the meridian of body and energy. we suppose that the appliance of magnets and needles has same effects.

• 대한한방내과학회지
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• 제22권3호
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• pp.405-413
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• 2001

Objective: Experimental studies were done to research the effects of Jahap-san(zige-san) on the allergic reaction Methods: For measuring the response about the antiallergic effect we investigated cytokines m-RNA expression of murine splenic B cell, production in anti-CD40 mAb-stimulated murine splenic B cells and the histamine release in IC-2 cells by anti-CD40 mAb-stimulated murine splenic B cells. Results: The extract of Jahap-san(zige-san) revealed significant decrease effect on cytokines m-RNA expression of murine splenic B cell, production in anti-CD40 mAb-stimulated murine splenic B cells and the histamine release in IC-2 cells by anti-CD40 mAb-stimulated murine splenic B cells. Conculusion : The extract of Jahap-san(zige-san) revealed significant effect on the antiallergy.

• 대한한방내과학회지
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• 제40권3호
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• pp.541-550
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• 2019

Objective: The aim of this clinical study was to describe the case of a patient who experienced chronic diarrhea related to seasonal changes that improved with herbal medicine treatment. Methods: A patient with diarrhea and globus hystericus was treated following treatment with Hoehyangbanchong-san-hap-Ukgan-san and Gamisachil-tang. A defecation and urination diary, the Bristol Stool Form Scale, and the Visual Analog Scale (VAS) were used to evaluate the effectiveness of this treatment. Results: During treatment, the patient's Bristol Stool Form Scale score changed from Type 7 to Type 4, and the VAS score was significantly decreased. The symptoms of diarrhea and globus hystericus almost subsided. Conclusion: In this case, Korean traditional herbal medicine reduced the clinical symptoms of diarrhea and globus hystericus.

• Communications for Statistical Applications and Methods
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• 제26권1호
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• pp.1-9
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• 2019

Various probabilistic methods have been proposed for using interpopulation allele frequency differences to infer the ethnic group of a DNA specimen. The selection of the statistical method is critical because the accuracy of the statistical classification results vary. For the ancestry classification, we proposed a new ancestry evaluation method that estimate the combined ethnicity index as well as compared its performance with various classical classification methods using two real data sets. We selected 13 SNPs that are useful for the inference of ethnic origin. These single nucleotide polymorphisms (SNPs) were analyzed by restriction fragment mass polymorphism assay and followed by classification among ethnic groups. We genotyped 400 individuals from four ethnic groups (100 African-American, 100 Caucasian, 100 Korean, and 100 Mexican-American) for 13 SNPs and allele frequencies that differed among the four ethnic groups. Additionally, we applied our new method to HapMap SNP genotypes for 1,011 samples from 4 populations (African, European, East Asian, and Central-South Asian). Our proposed method yielded the highest accuracy among statistical classification methods. Our ethnic group classification system based on the analysis of ancestry informative SNP markers can provide a useful statistical tool to identify ethnic groups.