• The Korean Journal of Food And Nutrition
• /
• v.17 no.4
• /
• pp.347-355
• /
• 2004

This study was undertaken in order to evaluate effects of methanol extracts of Stachys sieboldii MIQ and its related enzyme activities in brain tissues of rats. Sprague-Dawley(SD) male rats were fed within a control group, which is a basic diet group. The experimental diet group was given 100 and 200 mg/kg to supervise 100 and 200 mg/kg body weight per day for 20 days. Lipid peroxide levels and acetylcholine esterase activity in brain tissues were slightly decreased at a dose dependent manner, in vitro. Lipid peroxide levels were also decreased at a dose dependent manner; methanolic extracts of Stachys sieboldii MIQ demonstrated significant inhibitory effects, in vivo. Monoamine oxidase and xanthine oxidase activities were significantly inhibited in the brain tissues of experimental group compared to control group and the ratio of type conversion of xanthine oxidase were decreased.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.25 no.1B
• /
• pp.62-70
• /
• 2000

Intelligent vehicles are equipped with radar sensors for collision avoidance. We present a method of suppressing mutual interference among pulse-type radars, where all the radars are standardized. We developed a method of separating the true self-reflection from the false one by controlling the pulse emission of a radar in anorhogonal ON, OFF pattern. Interference signal identified in OFF-intervals is recorded to indicate the positions of the expected ghosts in ON-intervals. PFA and PM are derived for a radar system with I-Q demodulation scheme, where Gaussian noise alone is Rayleigh-distributed and Gaussian noise plus reflected radar pulse are Rician-distributed. The value of the threshold adaptively updated in order to prevent the deterioration of PM. In the experimental result, PFA decreases by an order of 10,000, when compared with the conventional M of N majority voting method.

• Journal of Life Science
• /
• v.18 no.2
• /
• pp.148-153
• /
• 2008

Phytochrome double mutant (PhyAB) showed the delayed root gravitropic response compared to the wild type (WT) in Arabidopsis. After 8 hr of gravistimulation, the gravitropic response of mutant showed 48% of the WT. The delayed response started at 1.5 hr after gravistimulation. And we measured the ethylene production in the root segments of WT and mutant for 12 hr. Ethylene production of mutant decreased about 40% of the WT at 12 hr. This result suggested that the phytochrome might be linked with ethylene production in some way. Generally, ethylene inhibits the growth of plant organs including roots. We measured the root growth rate in the presence of ACC (1-aminocyclopropane-1-carboxylic acid), a precursor of ethylene. And WT showed the inhibition of root growth with ACC, but mutant did not show the inhibition as WT did. To confirm the relationship between the ethylene and gravitropic response, we measured the gravitropic response with ACC. In the presence of $10^{-6}$ M ACC, WT showed the 37.4% inhibition compared to the control (no ACC), whereas mutant showed the only 6.6% inhibition of control (no ACC). This research suggested the relationship between phytochrome and gravitropic response through an ethylene production.

• Proceedings of the KIPE Conference
• /
• 2004.11a
• /
• pp.5-9
• /
• 2004

본 논문에서는, 벨트 연결형 기동발전기(Integrated Starter Generators)를 이용하여 승용 자동차에서 엔진 기동 시 발생하는 토크 맥동을 억제하는 방법을 제안하였다. 기동발전기의 빠른 토크 응답성을 통하여 내연기관의 기동 시 발생하는 저 주파수의 진동을 억제하여 승용차의 승차감을 개선하고자 한다. 특히 벨트를 통하여 구동되는(또는 구동하는) 벨트 연결형 기동발전기에 있어 벨트의 특성 분석과 모델링을 통하여 효과적인 맥동토크 억제 법을 제시하였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 1999.05a
• /
• pp.45-45
• /
• 1999

일반 구조용 탄소강은 수용액 중에 노출될 때 부식에 의한 손상을 받기 쉽다. 부식의 양지를 위한 방법으로 사용 매체 중에 부식억제제를 첨가하여 탄소강의 부식속도를 낮추는 방법은 흔히 사용되는 방법이다. 부식억제제는 부식억제의 원리에 따라 양극부식억제제, 음극부식억제제 그리 고 이들의 혼합부삭억 세제 둥 여러 종류가 목적에 따라 사용되고 있다. 일반적으로 부식억제제의 성능 평가에는 무게감량볍, 표면분석법, 분극거동측정, 부석전위, 선 형분극법에 의한 부식속도 측정 등 다양한 방법이 시도되고 있다. 이 중에서 전기화학적 평가볍 은 부삭억제제의 작용 기구 규명 등을 위하여 많이 사용되고 있다. 한편 제품의 개발 단계에서 실질적인 평가법으로 갈리 사용하고 있는 방법은 무게 감량법인데 이 방법은 전면부식에 의한 금 속 손실량을 측정하여 부식억제능을 측정하는 방법이다. 그러냐 실제로 부삭억제제가 사용되고 있는 환경에서의 부식양상을 판찰하여보면 전면부식에 의한 손상보다는 국부부식에 의한 손상이 보다 치명적언 경우를 종종 목격할 수 있다. 이러한 관점에서 가존의 무게감량법은 한계가 있다. 따라서 본 연구에서는 이러한 국부부식을 보다 효과적으로 평가하기 위해 새로운 시험법을 도 입 상용 부식억제제의 종류별로 비교하였다. 부식억제제로는 수용액 중의 부식억제제로 널리 사용되고 있는 Nalco 39L과 본 연구실에서 SK해미칼과 공동 개발한 GH-110 등에 대하여 MCA(Multiple Crevice Assembly)를 이용 틈부식 저항성을 평가하였다. 또한 박막화된 전기저항형 부석속도 측정 센서를 틈부식 형태의 부식측정 에 적용하는 연구를 행하였다. 시험에 사용한 재갚는 천연가스의 감압 온도보상용으로 운전하는 가스히터의 주 구성 재료인 저탄소강을 사용하였으며 열화된 부식억제제 용액으로 사용기간이 서로 다른 수용액들에 대하여 평가 방법을 적용하여 비교하였다 다양한 부식억 제 제 수용액을 비교한 결과 MCA(Multiple Crevice Assembly)를 이용한 틈부식 억제능 시험은 실제 현장 사험 결과와 어느 정도 일치하는 결과를 보였다. 새로운 틈부식 저항성 측정법으로 시도한 철박막을 이용 틈부식 측정법은 육안 검사를 실시하지 않고도 틈부식의 전행 여부를 확인할 수 있는 가능성을 확인하였다.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.11 no.3
• /
• pp.274-283
• /
• 2006

The Permanent Magnet Synchronous Motor(PMSM) drive systems with ball-screw, gear and timing-belt are widely used in industrial applications such as NC machine, machine tools, robots and factory automation. These systems have torsional vibration in torque transmission from servo motor to mechanical load due to the mechanical couplings. This vibration makes it difficult to achieve quick responses of speed and may result in damage to the mechanical plant. This paper presents adaptive notch filter with auto searching function of vibration frequency to reject the mechanical vibration of linear feeder system with PMSM. The proposed adaptive notch filter can suppress the torque command signal of PMSM in the resonant bandwidth for reject the mechanical torsional vibration. However, the resonant frequency can vary with conditions of mechanical load system and coupling devices, adaptive notch filter can auto search the vibration frequency and suppress the vibration signal bandwidth. Computer simulation and experimental results shows the verification of the proposed adaptive notch filter in linear feeder system with PMSM.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2007.11a
• /
• pp.38.1-38.1
• /
• 2007

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.12
• /
• pp.480-490
• /
• 2018

This study investigated the profiles of anger expression (anger control, anger in, anger out) and their variation in forms, and determined the differences in depression, aggression, and negative affect intensity of middle school students. For this purpose, the survey responses of 296 middle school students in Seoul were analyzed. The major study results are as follows. (1) Cluster analyses yielded four anger expression profiles: cluster 1 was characterized by high scores for anger control, anger in and anger out, cluster 2 by low scores for anger control, high scores for anger in and anger out, cluster 3 by low scores for anger control, anger in and anger out, and cluster 4 by low scores for anger in, high scores for anger control and anger out. (2) Between-cluster differences in depression, aggression, and negative affect intensity were all significant. The posteriori test indicated that cluster 4 was higher than the other three clusters in terms of depression. Cluster 3 was higher than the other three clusters on aggression, cluster 2 was higher than cluster 4 in terms of aggression. The interventions by aggression expression cluster are discussed and the implications of this research to education and counseling are explained.

• Tuberculosis and Respiratory Diseases
• /
• v.40 no.4
• /
• pp.395-403
• /
• 1993

Background: The cell cycle is composed of a series of steps which can be negatively or positively regulated by various factors. Alteration or inactivation of p53 by mutations, or by its interactions with oncogene products of DNA tumor viruses, can lead to cancer. Mutations of the p53 gene occur frequently in human primary lung cancers and the wild-type p 53 allele is often concomitantly deleted. These suggest that deprivation of suppressive role of the wild-type p53 may ensure tumor cell growth presumable by the mutant p53 gene. Methods: In an attempt to investigate this hypothesis, a mutant p53 gene was immunohistochemically demonstrated in the formalin-fixed paraffin-embedded tissue sections of lung cancers by using a monoclonal antibody p53 (Ab-3 and clone DO7). Results: The expression of p53 (DO7) was found in all four normal lung tissues, four small cell carcinomas, and four non small cell carcinomas in histologic types of lung cancer. In the six normal lung tissues the expressions of p53 (Ab-3) were not found. Contrarily, the expression of p53 (Ab-3) was found in the nuclei of lung cancers among fifteen (46.9%) of thirty-two cases studied. The expression of p53 (Ab-3) was disclosed in three case (37.5%) of eight small cell carcinomas and twelve cases (50.0%) of twenty-four non small cell carcinomas in histologic types of lung cancer. Conclusion: These findings suggest that expression of the mutant p53 is related to the one of events in the pathogenesis of human lung cancer and the role of the other oncogenes might be also related to the development of lung cancers.

• Korean Journal of Weed Science
• /
• v.30 no.3
• /
• pp.300-307
• /
• 2010

Greenhouse experiment was conducted to evaluate tolerance of six rice cultivars, three Indica${\times}$Japonica rice (long grain, cv. Dasanbyeo, Segejinmi and Hanareumbyeo) and three Japonica rice (short grain, Nampyung, Ilpumbyeo and Junamjosaeng) cultivars, to mesotrione+pretilachlor (MP) and bensulfuron-methyl+mesotrione+pretilachlor+pyriftalid (BMPP) in transplanting rice. Two herbicides were applied at 90 g and 180 g a.i. $ha^{-1}$ to three to four leaf stage rice at 5 and 15 days after transplanting, respectively. Related study was also conducted to compare $GR_{50}$ for Indica${\times}$Japonica and Japonica rice cultivars at different MP rates. Response to two herbicides varied with respect to rice cultivars and herbicide rates. All Indica${\times}$Japonica rice cultivars exhibited susceptible to both MP and BMPP as reflected by increased visual injury, shorter plant height and higher plant dry matter reduction when compared with nontreated rice cutlivars. The degree of foliar chlorosis by MP at 90 g a.i. $ha^{-1}$ was 5~6 at 7 days after treatment(DAT) but it was decreased to 3~6 at 14DAT. The degree of leaf chlorosis treated with 180 g a.i. $ha^{-1}$ MP was 6~7 at 7DAT and it was also decreased to 3~8 at 14 DAT. The plant hight of Indica${\times}$Japonica rices was inhibited by 18~43% at application of 90 g a.i. $ha^{-1}$ MP and 30~50% at 180 g a.i. $ha^{-1}$ MP. The dry matter reduction was greater than that of plant height inhibition, showing 46~73% at 90 g a.i. $ha^{-1}$ MP and 65~82% at 180 g a.i. $ha^{-1}$ MP. Similar leaf chlorosis injury and growth inhibition of rice cultivars was observed in the BMPP treatment. The injury and growth inhibition by MP and BMPP increased with increase in herbicide rate from 90 g a.i. $ha^{-1}$ to 180 g a.i. $ha^{-1}$. However, most of the Japonica cultivars are tolerant to MP and BMPP at both rates. There was no visible leaf chlorosis but plant height and dry matter production were slightly reduced at 180 g a.i. $ha^{-1}$. Based on $GR_{50}$ value determined in reduction of shoot dry weight for MP, the Indica${\times}$Japonica rice showed 12.9 fold lower compared with the Japonica rice. The result indicates that rice cultivars vary in tolerance to herbicides of MP and BMPP and Indica${\times}$Japonica rices were more susceptible than the Japonica rices to the MP and BMPP.