• 한국태양에너지학회 논문집
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• 제21권1호
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• pp.43-49
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• 2001

Informations of the solar radiation component are essential for modeling various solar energy systems. These Informations are particularly used for middle and high temperature applications, those need concentrating direct normal insolation. In order to estimate the performance of concentrating systems, it is necessary to know the intensity of the beam radiation, as only this component can be concentrated. The Korea Institute of Energy Research(KIER) has began collecting solar radiation component data since August, 1996. KIER's component data will be extensively used by concentrating system users or designers as well as by research institutes.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.701-705
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• 2006

This paper dealt with a component test of train control and management system(TMS) developed for korean tilting train express(TTX). This system that is established on TTX monitors and controls action of various devices by running of the train. Also, to performance estimation of the TMS, it is essential to verify a composition and function of TMS. Therefore, this study reviewed standards related on a component test of the TMS and confirmed test items, test conditions and evaluation basis on a Component Test. Running Test of TTX can verify performance of TMS and communications with other devices and secure reliability of TMS.

• 소음진동
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• 제9권2호
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• pp.401-408
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• 1999

A method is presented for the vibration analysis of steam turbine-generator rotor system based on the component mode synthesis method. The motion of each component of the system is described by superposing constraint mode associated with boundary coordinates and constrained normal modes associated with internal coordinates. This method using real fixed-interface modes allows for significant reduction in system model size while retaining the essential dynamic characteristics of the lower modes. The capability of this method is demonstrated in the natural frequency and unbalance response analysis of the steam turbine-generator rotor system in which the dynamics of the pedestal is considered. The results by the present method are compared with finite element method and trnasfer matrix method in terms of the accuracy and computing time.

• 한국컴퓨터정보학회논문지
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• 제7권3호
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• pp.16-22
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• 2002

컴포넌트의 효율적인 검색은 컴포넌트에 기반한 소프트웨어 개발에 필수적이다. 패싯 방식은 컴포넌트 검색 방법의 하나로 많은 연구의 대상이다. 이 논문에서 여러 개의 패싯값에 대한 논리 부정 검색에 사용되는 가중치 신경 접속 행렬을 효율적으로 만드는 새로운 알고리즘을 제안한다. 이 알고리즘을 사용하여 연산에 드는 복잡도를 향상할 수 있다. 또한 여러 개의 서로 다른 패싯을 사용하는 경우 이에 대한 논리적인 검색이 가능하도록 새로운 연산 방법을 제안하다.

• International Journal of Contents
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• 제14권4호
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• pp.24-29
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• 2018

EEG-based brain-computer interfaces has focused on explicitly expressed intentions to assist physically impaired patients. For EEG-based-computer interfaces to function effectively, it should be able to understand users' implicit information. Since it is hard to gather EEG signals of human brains, we do not have enough training data which are essential for proper classification performance of implicit intention. In this paper, we improve the subject independent classification of implicit intention through the generation of additional training data. In the first stage, we perform the PCA (principal component analysis) of training data in a bid to remove redundant components in the components within the input data. After the dimension reduction by PCA, we train ICA (independent component analysis) network whose outputs are statistically independent. We can get additional training data by adding Gaussian noises to ICA outputs and projecting them to input data domain. Through simulations with EEG data provided by CNSL, KAIST, we improve the classification performance from 65.05% to 66.69% with Gamma components. The proposed sample generation method can be applied to any machine learning problem with fewer samples.

• Food Science and Biotechnology
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• 제14권4호
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• pp.450-455
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• 2005

This study was conducted to determine firstly the composition of the essential oil from fresh changpo (Acorus calamus var. angustatus Bess) roots quantitatively and qualitatively by use of two internal standards, and secondly volatile compounds which are primarily responsible for the aroma of changpo roots. Simultaneous steam distillation and extraction method was used for essential oil extraction, and aroma extract dilution analysis (AEDA) and sniffing test by gas chromatography/olfactometry (GC/O) were used to detect the characteristic impact odorants. According to the instrumental analysis of changpo root essential oil, cis, trans-famesol (47.56 mg/kg of fresh wt), octanoic acid (23.73 mg/kg of fresh wt), trans-2-dodecenal (20.28 mg/kg of fresh wt) and trans, trans-farnesol (13.81 mg/kg of fresh wt) were the most abundant compounds. Geranyl acetate, trans-nerolidol and trans, trans-farnesyl acetate were evaluated as the characteristic impact odorants of changpo roots from results of AEDA and sniffing test. Especially, geranyl acetate was considered as the most similar odor component to changpo roots by organoleptic evaluation with GC/O.

• Natural Product Sciences
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• 제13권1호
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• pp.85-89
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• 2007

To determine whether the essential oil from Coriandum sativum and its main component, linalool, exhibit antifungal activity, we employed a broth dilution assay and disk diffusion test using common pathogenic Candida and Trichophyton species. Both coriander oil and linalool significantly inhibited growth of the tested fungi, with minimal inhibitory concentrations (MICs) in the range of $0.03{\sim}2mg/ml$. Furthermore, in a checkerboard titer test, both the oil fraction and linalool exhibited synergism when combined with ketoconazole, with resultant FICIs ranging from 0.06 to 0.53. Notably, hyphal formation in C. albicans cells was obviously inhibited by C. sativum essential oil in this experiment.

• Natural Product Sciences
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• 제11권2호
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• pp.92-96
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• 2005

The antifungal activities of essential oils from the leaves of Glehnia littoralis, which is cultivated in Korea, were evaluated against pathogenic Trichophyton species by the broth dilution method and the disk diffusion test. Additionally, the effects of the oils together with ketoconazole were tested by the checkerboard titer test. The essential oil fraction and its main components showed significant inhibition of the tested Trichophyton fungi, with minimal inhibitor concentrations (MICs) in the range of 16-32 mg/ml. The results suggest that activities of this oil are based mainly on the contents of ${\alpha}-pinene$ (22.17%), the next prominent component of the oil fraction, while the first main components ${\beta}-pinene$ (57.83%) have relatively mild activity. The MICs of ${\alpha}-pinene$ and ${\beta}-pinene$ were 1-4 mg/ml and 4-32 mg/ml, respectively. Additionally the Glehnia oil fraction and its main components as well, exhibited significant synergism with ketoconazole against Trichophyton rubrum.

• 품질경영학회지
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• 제19권2호
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• pp.117-124
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• 1991

In this paper, it is assumed that a system is composed of an essential unit and a nonessential unit. During the running of the system, an essential unit is replaced at periodic replacement time T or at nth failure of essential unit whichever occurs first. Nonessential unit is replaced at its failure and at the replacement of essential unit. This paper derive optimal replacement period which minmises the total expected cost for replacement. The unimodality of totoal maintenance cost function is proved under the assumption that hazard rate of each component is continuous and monotone increasing failure rate(IFR). Based on this condition, it is shown that the optimal replacement period is finite and unique.

• 약학회지
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• 제58권1호
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• pp.58-61
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• 2014

The essential oil was extracted from the roots of Angelica dahurica Bentham et Hooker f. by steam distillation and its composition was analyzed by GC-MS. The antifungal activities were evaluated by micro-dilution method against five Aspergillus and three Trichophyton species. The most abundant component was ${\alpha}$-pinene (17.21%) among 40 compounds identified in this oil. The essential oil fraction of A. dahurica and ${\alpha}$-pinene exhibited marked inhibiting activities against the tested Aspergillus and Trichophyton species with MICs (minimum inhibitory concentrations) between 0.12 mg/ml and 8 mg/ml.