• Journal of Electrical Engineering and Technology
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• 제12권5호
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• pp.1851-1863
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• 2017

Interior permanent magnet synchronous motor (IPMSM) is most commonly used in the automotive industry as a traction motor for electric vehicle (EV). In electric vehicle, the torque output rapidly changes according to the operation of the accelerator and the braking of the driver. The transient torques are thus generated very frequently in accordance with the variable speed control of the driver. Therefore, in this paper, a method for improving the torque response in the transient states of IPMSM is proposed. In order to complement the disadvantages of the conventional PI current controller in the field oriented control (FOC), the finite-state model predictive current control and 2D-LUT is applied to improve the torque response at the torque transient period. Simulation and experiment results are given to verify the reliability of the proposed method.

• 항공우주산업기술동향
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• 제8권1호
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• pp.45-54
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• 2010

본 논문에서는 최근에 개발된 고해상도 지구관측위성의 본체 형상설계 동향에 대해 기술하고자 한다. 인공위성의 본체는 임무, 탑재체, 발사환경, 임무특성, 자세제어 및 추진시스템에 따라 다양한 형상을 갖는다. 또한 2000년대 들어서 시작된 위성영상의 상업화에 따른 영상수요의 증가는 고해상도 영상을 신속히 많이 획득할 수 있는 위성시스템을 요구하고 있다. 이러한 요구에 맞춰 위성의 본체는 가벼우면서도 안정적으로 탑재체를 지지할 수 있도록 설계되고 있으며, 이 중에 형상설계 변화를 본 논문에서 집중적으로 살펴본다.

• Composites Research
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• 제28권3호
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• pp.99-103
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• 2015

본 논문에서는 복합재료 제조공정 중 온도에 따른 경화 반응을 이해하고 열분석을 수행하였으며, 이 결과를 바탕으로 온도에 따른 수지의 경화도 및 비열의 변화를 수식화하였다. 온도에 따른 경화도와 비열은 DSC와 MDSC (Modulated DSC)를 활용하여 측정하였다. DSC와 MDSC 분석은 Isothermal과 Dynamic 조건으로 수행하여 Cure Kinetics, 유리전이온도 및 비열을 측정하고, 회기 분석 방법을 이용하여 물성거동을 수학적으로 모델링하였다.

• Journal of Microbiology and Biotechnology
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• 제5권3호
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• pp.125-131
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• 1995

A 3, 346 bp of the cdd upstream region in Bacillus subtilis was sequenced from the pSO1 (Song BH and J Neuhard. 1989. Mol. Gen. Genet 216: 462-468) and sequence homology was searched to the known genes in Genbank and European Molecular Biology Laboratory databanks. Five complete and one truncated putative coding sequences deduced from the nucleotide sequence were found through the ORF searching by Genetyx and Macvector software, and one of them was identified as the dgk (diacylglycerol kinase) gene and another, a truncated one, as the phoH (phosphate starvation-inducible gene) gene. The B. subtilis dgk gene, having a role for response to several environmental stress signals, revealed an open reading frame of 134 amino acids with 43.1% of sequence identity to the Streptococcus mutans dgk gene. The carboxy terminal 59 residues of the truncated phoH gene showed 52.7% and 34.5% of sequence identity in amino acids with the corresponding genes of Mycobacterium leprae and Escherichia coli. The four remaining coding sequences consisting of 115, 421, 91, and 91 residues were thought to be unknown ORFs because they have no significant similarity to known genes.

• 한국정보교육학회:학술대회논문집
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• 한국정보교육학회 2009년도 하계학술대회
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• pp.189-194
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• 2009

디지털교과서 시범사업은 미래교육의 시발점으로서 다양한 장점 및 교육적 효과를 제공할 수 있다. 한편 디지털교과서 환경에서는 현실세계와 유사한 태블릿 PC 기반의 펜 스케치를 메타포로 사용하고 있으며, 디지털 잉크 기반의 이러닝은 다양한 교육적 장점을 제공할 수 있다. 그러나 현재 보급되고 있는 디지털교과서 콘텐츠는 펜 기반의 메타포를 고려하지 않은 서책형 교과서의 멀티미디어 버전 형태이며 그 결과 태블릿 PC의 본연의 기능을 충분히 활용하지 못하고 있다. 따라서 본 연구에서는 학습자가 자기주도적으로 전자 펜 기반 스케치 입력방식을 통해 문제를 해결하고 학습의 결과물을 직접 확인할 수 있는 스케치 기반의 인터페이스를 설계 및 적용하여 교수자와 학습자간의 활발한 상호작용을 제공하고자 한다. 본 연구의 결과는 온라인 교육이나 전자 책, 지능형 교육 시스템 등 상호작용이 가능한 교육용 콘텐츠 개발에 확대 적용될 수 있을 것으로 기대한다.

• 항공우주기술
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• 제10권2호
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• pp.94-100
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• 2011

본 논문에서는 고성능 저궤도 지구관측위성의 예비연성하중 해석결과에 대하여 평가한다. 연성하중해석을 수행하기 위하여 위성체 모델을 Craig-Bampton 모델로 축약한 후 발사체 개발업체로 제공하였다. 제공된 Craig-Bampton 모델은 인공위성의 질량행렬, 강성행렬, 가속도변환행렬 및 변위변환행렬이다. 발사체 개발업체에서는 위성체 Craig-Bampton 모델과 발사체 모델을 결합하여 연성하중해석을 수행한 후 그 결과를 제공하였다. 제공받은 연성하중해석 결과를 바탕으로 발사시 위성체가 구조적으로 이상이 없는지를 평가하였다. 평가결과 위성체는 발사하중하에서 안전함을 확인할 수 있었다.

• 한국학교보건학회지
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• 제27권2호
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• pp.59-68
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• 2014

Purpose: The purpose of this study was to investigate the intention of smoking cessation according to the level of cigarette price increase among adolescent smokers and to suggest a reasonable cigarette price to effectively reduce smoking prevalence. Methods: In 2007, subjects were selected from middle and high school students except twelfth graders using a complex sampling design which employs a two-stage cluster sampling method. In total, 1,001 current smokers were included in the study. To investigate the intention of smoking cessation according to the level of cigarette price increase, cumulative percentages of smoking cessation of every smoking-related subgroup were presented under the assumption that cigarette prices increased to 3,000, 4,000, 5,000, 6,000 or 10,000 won. Non-parametric statistical methods were used to compare the prices at which the subjects intended to quit smoking among the subgroups. Results: More than 50 percent of current smokers intended to quit smoking under the assumption that cigarette prices were doubled to 5,000 won. However, the effect of cigarette prices on smoking cessation was less sensitive when the prices exceeded 5,000 won. In addition, the median of cigarette prices at which the subjects intended to quit smoking was 5,000 won, excluding the subjects who smoked less than a cigarette a day. Conclusion: This study suggests that 5,000 won for one pack of cigarettes is a reasonable price to effectively encourage smoking cessation, considering the price elasticity. Therefore, this finding may be helpful in establishing a new cigarette price policy for anti-smoking.

• 대한한방내과학회지
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• 제25권4호
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• pp.383-390
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• 2004

The most common causes of severe sleepiness beginning or progressively worsening in adults are SLEEP APNEA and RELATED BREATHING DISORDERS DURING SLEEP. Idiopathic hypersomnia is excessive sleeping without obvious cause. Idiopathic hypersomnia diagnosis can be explained as follows: One could be chronically sleepy due to either something wrong with sleep that makes it non-refreshing, or a problem with the brain mechanisms which normally should keep one alert whether caused by primary problems within the brain or its chemistry, or by other factors (such as sedating medications or thyroid problems). A 71-year-old male who had suffered from excessive sleeping was admitted to our department for oriental treatment on 7th of July, 2003. He was diagnosed as an idiopathic hypersomnia for excessive sleeping without obvious cause. Initial treatment modalities with administration of "SoonHwanGi1HoBang(循環器1號方)" were not effective. However, after administration of "YukMiGiHwangTang(六味地黃湯)" desirable effects were seen.

• 동아시아식생활학회지
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• 제20권2호
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• pp.239-247
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• 2010

This study was conducted to increase the keeping quality of the minimally processed pear slices during the cold storage. Korean pears, 'Shin-go (Niitaka)', 'Chu-hwang' and 'Won-hwang’ were immersed in 1% ascorbic acid, 0.1% calcium propionate, 1% citric acid, 0.2% N-acetyl cysteine and 0.5 M 4-hexylresorcinol solution for 3 three minutes and then stored at $1{\pm}0.5^{\circ}C$ for 10 days. We have also examined into the firmness and the color difference of pears slices as affected by the application of the anti-browning agents. The firmness of pears slices which that were immersed in 0.1% calcium propionate and 0.2% N-acetyl cysteine solution were not significant at did not differ significantly after 10 days after of cold storage. However, the ${\Delta}E^*$ values of 'Shin-go' slices which that were treated with 0.1% calcium propionate and 0.2% N-acetyl cysteine solution and stored for 10 days decreased by 3.18 and 3.83, when compared with that in of the control, which decreased by 6.36. The ${\Delta}E^*$ values of 'Chu-hwang' slices which that were treated with 0.2% N-acetyl cysteine and 0.1% calcium propionate solution had the slight difference by differed by only 2.09 and 2.14, when compared with that in of the control, which differed by 3.04. The ${\Delta}E^*$ values of 'Won-hwang' slices which that were treated with 1% citric acid and 0.5 M 4-hexylresorcinol were 4.49 and 5.83, respectively, while that in of the control decreased by 8.95. It was assumed that the anti-browning agent treatment had the different activities among varieties of the pear varieties slices, however, application of 0.2% N-acetyl cysteine and 0.1% calcium propionate application had greater the higher antibrowning activity.

• Molecular & Cellular Toxicology
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• 제2권2호
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• pp.141-149
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• 2006

Tamoxifen (TAM), a non-steroidal anti estrogen anticancer drug and chemopreventive agent for breast cancer, have caused cholestasis in liver. The potent hepatocarcinogenicity of this drug has been reported. Methotrexate (MTX) is dihydrofolate reductase inhibitor which interfaces with the synthesis for urine nucleotide and dTMP. And it may cause atrophy, necrosis and steatosis in liver. These two anticancer drug have well-known hepatotoxicity. So, in this study we compare the gene expression pattern of antitumor agent TAM and MTX, using the cDNA microarray. We have used 4.8 K cDNA microarray to identify hepatotoxicity-related genes in 5-week-old male Sprague-Dawley (SD) rats. Confirm the pattern of gene expression, we have used Real time PCR for targeted gene. In the case of MTX, Protease related gene (Ctse, Ctsk) and Protein kinase (Pctk 1) have shown specific expression pattern. And in the case of TAM, apoptosis related gene (Pdcd 8) and signal transduction related gene (kdr) have significantly up regulated during treatment time. Gene related with growth factor, lipid synthesis, chemokins were significantly changed. From the result of this study, the information about influence of TAM and MTX to hepatoxicity will provide.