• 전자공학회논문지 IE
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• v.45 no.4
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• pp.11-18
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• 2008

This study is implementation of attitude control system(ACS - Attitude Control System). for a multi legs robot. This study designs H/W of Inertial Measurement Unit (IMU) and attitude control algorithm S/W. Compare performance with Mtx and MTx in order to verify action performance of this system after implementation, and will verify a system integrated IMU of a multi-legs robot. ACS uses Gyro and an accelerometer and an earth magnetism sensor, and it is a system controlling a roll, pitch angle attitude of an object. Generally, low price MEMS is difficult to calculate a correct situation of an object as an error occurs severely the Inertial sensor. This study implements IMU in order to develop ACS as use MEMS, accelerometer, Gyro sensor and earth magnetism sensor. Design algorithm each a roll, pitch, yaw attitude guaranteeing regular performance, and do poling in a system as include an attitude calculation program in an IMU system implemented. Mixed output of Gyro and an accelerometer, and recompensed a roll, pitch angle, and loaded in this study on a target platform in order to implement the ACS which guaranteed performance more than a continuously regular level, and operated by real time, and did porting, and verified.

• Polymer(Korea)
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• v.38 no.2
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• pp.156-163
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• 2014

Hydroxyapatite has osteoconductivity, biocompatibility and noninflammatory, and it has been used clinically as artificial bone. In this study, we prepared hydroxyapatite/poly(lactic-co-glycolic acid) (PLGA) scaffolds using 0, 10, 20, 40 and 60 wt% of hydroxyapatite. We analyzed compressive strength, SEM analysis and FTIR for mechanical property of 3D hydroxyapatite/PLGA scaffolds. For biocompatibility tests, cell proliferation and viability were measured via MTT assay and SEM. We analyzed RT-PCR, FACS, histology (H&E, ED-1) for anti-inflammatory effect. This study showed that hydroxyapatite hybrid scaffolds have low inflammatory reaction compared with the PLGA. This result has a potential for the application of artificial bone graft material.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.739-744
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• 2020

This study evaluates the erosive potential and effects of mixed alcohols by analyzing the pH, titratable acidity, and fluorescence loss degree (△F). Following alcohol groups were investigated: Soju, Calamansi+soju, Yakult+soju, Cola+soju, and Energy drink+soju. The ratio of soju:beverage in the alcohol mixtures was 7:3. Ed. Notes: The sentence lacks clarity. Please review if the edit correctly portrays the meaning. If not, please revise appropriately. Measurement of the pH and titratable acidity (the amount of 1M NaoH solution required to raise to pH 5.5 (TA5.5) and 7.0 (TA7.0)) of alcohols was achieved by stirring with pH meter. The erosive effect of the alcohol mixtures on bovine tooth (△F) after 1, 2, 4, and 6 hours exposure were analyzed by quantitative light-induced fluorescence (QLF-D). All the mixed alcohols in this study showed an acidic pH, lower than 4.5. The average pH of mixed alcohols was 3.17 ± 0.50 whereas the pH of Soju was 8.6 ± 0.01. The TA5.5 and TA7.0 values of the mixed alcohols were 0.5~18 and 0.5~23.5, respectively. △F of the three tested mixed alcohol groups (except yakult+soju group) were observed to increase in a time-dependent manner. The calamansi mixed alcohol had the highest acidity potential and erosive effect among the tested groups. Taken together, the results indicate that the mixed alcohols have a strong erosive effect and potential on dental enamel.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.2
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• pp.169-178
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• 2010

The present study was conducted with four ruminally fistulated cattle to examine the fermentation characteristics and effective degradability (ED) in the rumen, and whole tract digestibility and TDN values of various silages (whole crop rye, RS; whole crop barley, BS; Italian ryegrass, IRGS and sudangrass, SGS) which were produced in Korea. The pH of rumen fluid were not greatly affected by silage at most times after feeding but SGS decreased (p<0.049) the ruminal ammonia-N concentration as 7.28 mg/100 ml at 3h after feeding compared to other silages. An acetate proportion from SGS feeding was higher at 1h (p<0.018), 3h (p<0.004) and 6h (p<0.019) after feeding than those from other silages. The propionate ($C_2$) proportion, however, was greater (p<0.001~p<0.042) for the RS and BS than the corresponding values of other silages up to 6h after feeding while the lowest $C_2$ proportion was observed from SGS. The butyrate proportion was lowest (p<0.007~p<0.027) in the cattle fed BS at 1~6h after feeding among silages. An ED of dry matter (DM) in the rumen was highest (P<0.048) for RS as 59.64%, and was reduced in the order of BS (56.12%), IRGS (55.64%) and SGS (54.02%). Similar tendency was observed in the EDs of crude protein (p<0.014) and organic matter (OM, p<0.039). The whole tract digestibility of DM (p<0.032), neutral detergent fiber (NDF, p<0.034) and OM (p<0.041) of SGS was greatly reduced. The TDN value based on whole tract digestibility of silages was highest for RS as 61.1%, and TDN values of BS, IRGS and SGS were 57.1%, 57.9% and 50.7%, respectively. Based on the results obtained from the present study, components in various whole crop silages produced in Korea might affect the ruminal VFA proportion, and especially, NDF content could greatly influence on the TDN value of silage calculated based on the NDF content.

• Journal of Life Science
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• v.23 no.8
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• pp.989-997
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• 2013

In this study, based on the antioxidative effects in organic solvent fractions obtained from the main methanolic extract of L. japonica, the protective cellular effects and gene expression patterns of ethyl acetate fractions on $H_2O_2$-induced Raw 264.7 cell death ($IC_{50}$) were analyzed. The antioxidant activity of the fractions measured using DPPH free radical scavenging activity increased in a dose-dependent manner, and the $ED_{50}$ exhibited the highest $39.56{\mu}g/ml$ in the ethyl acetate fraction. In addition, the ethyl acetate fractions' cell viability on $H_2O_2$-induced Raw 264.7 cell damage increased in a concentration-dependent manner, showed a visible cell survival rate of 82.49% at a concentration of $100{\mu}g/ml$. The gene expression patterns related to the ethyl acetate fractions' cytoprotective effect in $H_2O_2$-induced Raw 264.7 cell damage presented similar patterns to those of BHA. In comparative analysis for antioxidant activity-related genes affected by ethyl acetate fractions and BHA in $H_2O_2$-induced Raw 264.7 cells, both ethyl acetate fractions and BHA showed very similar gene expression patterns, but the gene expression level of the heme oxygenase 1 (Hmox1) gene making antioxidant enzymes in cells was four times higher in ethyl acetate fractions than BHA. In inflammation-related genes in $H_2O_2$induced Raw 264.7 cells, the T-box transcription factor (Tbx21) gene was expressed about two times more frequently in the ethyl acetate fraction treatment group, while it was expressed half as frequently in the BHA treatment group.

• 대한위암학회:학술대회논문집
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• 2002.04a
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• pp.9-17
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• 2002

위의 parietal cell 혹은 대식세포와 유사한 세포 내부에서 H. pylori가 발견된다는 보고가 있기는 하나 일반적으로 H. pylori는 Shigella와 같은 침습성 세균은 아닌 것으로 알려져 있다. 그럼에도 불구하고 H. pylori에 감염된 위점막에는 많은 수의 호중구를 위시한 염증세포의 침윤이 관찰되는데 H. pylori가 위상피세포에 부착 할 경우 위상피세포를 자극하여 interleukin-8을 위시한 cytokine 을 발현케하고 이에 의하여 호중구 등의 염증세포가 몰려들게 된다. 한편 고유층에 몰려든 호중구에서는 다시 interleukin-8을 위시한 일련의 호중구 활성화 chemokine을 분비하여 염증반응을 증폭해 나갈 것이다. 호중구에서 발현되는 myeloperoxidase나 활성 산소 등도 위점막의 조직 손상에 기여할 것이다. 위상피세포를 덮고 있는 점액층은 위상피세포를 보호한다고 알려져 있으나 H. pylori 감염의 경우 점액층에 의하여 H. pylori의 운동성이 증가하고 이것이 위상피세포로부터의 cytokine 발현을 자극하여 염증반응을 증폭하는데 관여할 가능성도 있다. H. pylori는 위상피세포에 대하여 apoptosis를 유도함과 동시에 고유층에 몰려든 호중구에 대하여는 apoptosis를 억제케하여 궁극적으로 염증반응을 증폭 및 지속시켜 나가는 쪽으로 작용한다. 한편 H. pylori는 위상피세포로부터 COX-2의 발현을 증가시키는데 이는 위상피세포의 apoptosis를 억제하는 방향으로 작용한다. 이외에 H. pylori의 urease에 의하여 발생한 암모니아나 H. pylori 자신이 분비하는 세포독소가 세포 손상을 유발할 가능성도 있다. 상술한 여러 독성 인자들 중 어느 하나가 단독으로 작용하기보다는 여러 인자가 같이 동시에 또는 시차를 두고 작용할 가능성이 많다고 생각된다.(\gamma-FeOOH)$, 침철광$(\alpha-FeOOH)$, 적금광$(\beta-FeOOH)$, 그리고 자철광$(Fe_3O_4)$이다. 인위적 부식에서는 전부 인철광의 부식물이 생성되었고 자연적 부식에서는 모두 침철광의 부식물이 생성되었다. 특히 철제 표면에 자연적으로 생성된 공식 녹을 XRD 분석한 결과 적금광으로 동정되었다. 이런 모든 시편들을 각 탈염방법에 따라 탈염처리한 후 XRD와 SEM-EDS으로 분석한 결과 인철광과 침철광은 어떠한 변화도 보이지 않았고, 다만 적금광으로 동정된 시편만이 잔존하지 않았다. 철기 제작별 $Cl^-$ 이온 추출량과 탈염효과에 대한 비교 실험은 이온 크로마토그래피 분석 결과와 마찬가지로 단조 철제유물이 주조 철제보다 $Cl^-$ 이온을 많이 가지고 있었으며, 탈염 처리 후에는 $Cl^-$ 이온은 전혀 발견되지 않았다. 이상의 결과 $K_2CO_3$와 Sodium 용액은 탈염처리에서 가장 적합한 탈염처리 용액으로 알수가 있었으며 특히 어떠한 탈염 용액으로 유물을 처리한다 해도 철제유물에 생성된 부식물은 제거되지 않는다는 것을 알게 되었다. 따라서 보존처리자는 유물 표면의 부식 상태만을 보고 처리하기 보다는 철기제작물로 고려하여 처리하는 것이 필요하다. 또한 금속에 부식을 야기시키는 $Cl^-$ 이온과 부식물을 완전하게 제거하여 탈염처리를 하는 것이 유물 부식을 최대한 지연시킬 수 있는 것이라 생각된다.TEX>$88\%$)였다.(P=0.063). 결론: 본 연구에서는 MTHFR C/T & T/T 유전자 다형성이 위암의 발생과 그 위치에 대해 관련이 있는 것으로 여겨지고, 흡연력, 음주력과는 관련이 없는 것으로 여겨진다.험이

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.8
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• pp.1102-1110
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• 2013

Following the extraction of oil for biodiesel production, oilseed press cakes are high in fat. As the dietary supplementation of fat is currently considered the most promising strategy of consistently depressing methanogenesis, it follows that oilseed press cakes may have a similar potential for $CH_4$ abatement. As such, this study aimed to characterise the nutritive value of several oilseed press cakes, glycerine and soybean meal (SBM) and to examine their effects on in vitro ruminal fermentation, digestion kinetics and $CH_4$ production. Moringa press oil seeds exhibited the greatest in sacco effective degradability (ED) of DM and CP (p<0.05). In vitro gas production (ml/g digested DM) was not affected (p = 0.70) by supplement at 48 h of incubation. In vitro DMD was increased with the supplementation of glycerine and SBM at all levels of inclusion. Moringa oilseed press cakes produced the lowest $CH_4$ (mg/g digested DM) at 6 and 12 h of incubation (p<0.05). The findings suggest that moringa oilseed press cake at 400 g/kg DM has the greatest potential of the oilseed press cakes examined in this study, to reduce $CH_4$ production, without adversely affecting nutrient degradability.

• Journal of Korea Society of Industrial Information Systems
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• v.7 no.5
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• pp.129-146
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• 2002

In this study, an effective methodology to introduce knowledge management system into the retail business is suggested by overall analysis of examples those were carried out in business area. different from existing studies, which focus on theoretical aspect only, this study focuses its attention on theoretical & practical aspect simultaneously and tries to find a long-term & integrated knowledge management strategy. With examining the examples of knowledge management, this study deals with the fundamental conception, the procedure and the organization of knowledge management. Moreover, this study practically analyzes the knowledge management system of the company named ″H″, one of the retail business companies. By clarifying the problems, which is involved in the knowledge management process of the above company, this study suggests an improvement methodology to introduce and settle down knowledge management system into retail business company for the future. This study has good results in the viewpoint that it gives a definite direction of knowledge management introduction. However, there is some limitation such as the insufficiency of examples and the omission of documented analysis. Therefore, this study leaves some task to be achieve ed in the future.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.30.2-30.2
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• 2009

TiO2는 3가지의 결정구조를 가지고 있으며 결정 입자, 구조, 상의 형태에 따라서 성질 및 기능에 영향을 주고 있다. anatase상의 애너지 밴드갭과 전자와의 재결합 확률이 크기 때문에 Rutile상 보다 우수한 성질을 갖고 있어 산화물 반도체로 이용하는 것이 적합하다. 본 실험에서는 나노로드의 TiO2를 수열처리법에 의해 합성한 후 박막을 제조하여 감응특성을 조사하였다. X선 회절분석기(X-Ray Diffraction)로 분석결과 ph=1의 루타일상을 제외하고, pH=2~7의 더 넓은 구간에서 뚜렷한 회절피크의 anatase 상이 나타났으며 다른 비정질상이 발생되지 않는 결정성이 좋은 단결정임이 나타났다. NaOH solution 을 이용하여 수열처리후 $180^{\circ}C$이상의 특정 온도 구간에서 수십 나노 로드 형태로의 2차 성장된 모습을 TEM과 EDS로 결정구조와 화학조성을 분석하였다. 그리고 BET 측정을 통해 $180^{\circ}C$의 소성온도에서 TiO2 입자의 비표면적이 가장 우수한 것으로 나타났다. 나노로드의 수용액을 Al2O3기판의 감지막 위에 떨어뜨려 네트워크된 막을 형성한후에 센서를 제작하였다. 히터 전압이 $400^{\circ}C$에서 나노 파우더센서에서는 반응이 일어나지 않은 반면, 나노 로드센서는 CH3SH에서 28% 의 높은 감도를 얻었고, Toluene의 반응에서는 15%의 감도가 나타났다. 그 외 NO, CO, H2등의 측정에서 아무런 반응이 일어나지 않았다. 이는 비교적 기공이 큰분자(Size)를 가진 CH3SH=76nm, Toluene=60nm에서 반응이 일어난 반면, H2=28nm, CO=22nm에서 감도가 나타나지 않은 것을 보아 흡착분자크기에 의한 영향이 큰 것으로 나타났다.

• Korean Journal of Microbiology
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• v.36 no.3
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• pp.236-241
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• 2000

A defensin is an inducible antibacterial peptide from a fleshfly and contains 40 residues basic peptide with six cysteines. For the consiruction of recombinant S cerevisiae expressing defensin, the structural gene coding for active defensin was chemically synthesized and fused in fiam to GAP promoter, MFul preprosequence and the GAL7 transcription terminator, generating a recombinant plasnlid pGMD18. S. ce~evisine 2805 Gells were transror~ned to uracil prototroph by the pGMDl8 arid the transformed cells showing antibacterial activity against 111. luteus TAM1056 were selected by growth inhibition zone assay. The optimal culture conditions for the unprovement of the defensin production of a selected tmdonnant were investigated. The optirmzed medium containing 0.4% yeast extract, 2% corn steep liquor, 2.5% glucose and 0.05% $C_2CO_3$, could be determined and the optimum lemperature. and initial pH could be detennnied as $28^{\circ}C$ and pH 3, ~mpectively. The optimized conditioiis revealed the trvofold Increase in the cell growth and the fourfold in the antibaclerial activity. coinpar-ed with tllc Yl'D medium.