• Journal of international Conference on Electrical Machines and Systems
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• 제2권3호
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• pp.361-366
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• 2013

This paper presents the effect on application of the flywheel energy storage system (FESS) for load frequency control (LFC) of an interconnected 2 area power system. To do this, the control characteristics with the FESS were compared with that of the conventional governor controller. The controller for the FESS control and the governor control used a PID type controller. Both the FESS PID controller and the governor PID controller using genetic algorithm (GA) were designed to optimize the PID parameters. The frequency and generation output characteristics with the only FESS controller and with the only conventional governor controller were compared. To verify robust performance of the FESS controller, the computer simulations were performed under various disturbances. The simulation results showed that the FESS controller provided better dynamic responses in comparison with the conventional governor controller.

• 전기학회논문지
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• 제68권1호
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• pp.8-12
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• 2019

Combined Cycle Unit(CC) generates the primary power from the Gas Turbine(GT) and supplies the remaining heat of the GT to the Steam Turbine(ST) to generate the secondary power from the ST. It plays a major role in terms of energy efficiency and Load Frequency Control(LFC). Incremental Heat Rate(IHR) curves of economic dispatch(ED) of CC is applied differently by GT/ST combination. But It is practically difficult because of performance test by all combinations. This paper suggests a reasonable method for estimating IHR curves for partial combinations(1:1~(N-1):1) using IHR curves when operating with GT alone(1:0) and with all(N:1) combinations of CC.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2015년도 춘계학술대회
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• pp.272-274
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• 2015

Success of communication at sea is directly linked with clear and complete delivery and receipt of the target message between interlocutors. It can be said that speakers' effective delivery of their intended message and listeners' precise decoding and accurate understanding are the keys to successful maritime communication. From this perspective, the scope of maritime English education and training needs to be reconceptualized and expanded into the area of communication itself, beyond the simple acquisition of, and familiarization with, IMO Standard Maritime Communication Phrases (SMCP). Therefore, in order to make learners' acquisition of marine communication knowledge more feasible, and the knowledge learned more practically applicable, training on effective and clear oral delivery should be also considered within the frame of maritime English education. Thus, critical training elements to realize this goal need to be suggested as guidelines. In this presentation, the theoretical background on this will be introduced in terms of English as a Lingua Franca (ELF) and Lingua Franca Core (LFC), which are the current mainstream forms of English communication in the international business context. Based on this, six key training elements will be discussed; that is, speech rate, word groups, pauses, nuclear stresses, consonants (including consonant clusters), and vowels (specifically long and short vowels). Finally, the practical pedagogical methods of each element, and its actual application into a real ESP classroom, will be suggested.

• 말소리와 음성과학
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• 제5권3호
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• pp.3-10
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• 2013

This study investigated the rhythmic accommodation of Korean English learners' interlanguage talk. Twelve Korean speakers, 6 native English speakers and 6 non-native English speakers in London participated in multiple conversations on different topics which produced 36 conversational data in interlanguage talk (ILT) settings. 190 utterances from the 36 conversational data were analyzed to investigate the rhythmic patterns of Korean English learners when they communicated with English speakers with different language backgrounds. Save for the final-syllable, the normalized duration of consecutive syllables was compared in order to derive a variability index (VI). It was found that there was no significant variability in the measurement of the syllable-to-syllable duration for the utterances of Korean English learners, regardless of their interlocutor's language background. Conversely, it was found that there was evidence that Korean English learners showed rhythmic accommodation in ILT when they conversed with non-native English speakers. The speaking rate became significantly slower when Korean English learners talked to non-native English speakers, than when they talked to other Korean English learners. Furthermore, there was a negative correlation between speaking rate and the VI in the utterances of Korean English learners in ILT.

• 동의생리병리학회지
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• 제22권1호
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• pp.100-107
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• 2008

The purpose of this research was to investigate the anti-inflammatory effects of Gagamtunong-san(GTNS) which has been medicated the patient such as mastitis. The results were as follows. The cytotoxicity on mouse lung fibroblast Cells(mLFC) was not served at all concentration of GTNS. GTNS in RAW264.7 cell inhibited $IL-1{\beta}$, IL-6, $TNF-{\alpha}$, COX-2 and NOS-II mRNA genes expression in a concentration-dependent manner. Specially GTNS inhibited NOS-II production very significantly at 100 ${\mu}g/ml$. GTNS inhibited NO production significantly in a concentration-dependent manner. GTNS inhibited ROS production in a concentration-dependent manner. GTNS inhibited $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$ production significantly in serum of acute anti-inflammation-induced mice. GTNS increased the survival rate from the 3rd day on LPS-induced lethal endotoxemia. These results suggest that Gagamtunong-san(GTNS) can be useful in treating a lot of women mammary diseases caused by inflammation such as acute and chronic mastitis.

• 한국지능시스템학회논문지
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• 제7권5호
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• pp.14-20
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• 1997

This paper proposes a new design method for the SMC-type FLC and shows that a SMC-type LFC is an extension of the SMC with BL. The conventional SMC-type FLC uses error and change-of-error as inputs of the FLC and generates the absolute value of a switching magnitude. Then, the fuzzy rule table is constructed on a two-dimensional space of the phase plane and has commonly the skew symmetric property. In this paper, we introduce a new variable, signed distance, from the skew symmetric property of the rule table. And thd variable becomes only a fuzzy variable that is used to generate the control input of a SMC-type FLC. that is, we design a new SMC-type FLC that uses a signed distance and a control input as the variables representing the contents of the rule-antecedent and the rule-con-sequent, respectively. Then the number of total rules is reduced and the control performance is almost the same as that of the conventional SMC-type FLC. Additionally, we derive the control law of the ordinary SMC with BL from a new SMC-type FLC. Namely, we show that a FLC is an extension of the SMC with BL.

• 전기학회논문지
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• 제65권7호
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• pp.1161-1168
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• 2016

Battery energy storage system(BESS) attract the attention of the power system operators with its fast response to a disturbance in spite of its limited energy capacity. This paper proposes the operating method of BESS for following the Automatic Generation Control(AGC) frequency control which is centrally distributed by a system operator. As BESS needs to just meet the control requirement from the system operator, it should be able to properly manage the state of charge(SOC) of BESS to be available to control signal. For doing these, the proposed method distributes the control requirement to available batteries in proportion to its SOC. In addition, unavailable batteries are controlled to recover the SOC to an appropriate range, and the recovering power is supplied by available batteries meeting the control requirement. Moreover, the proposed method manages the efficiency of power conversion system (PCS) by limiting the number of PCS to be assigned for the low control requirement. Finally, the case studies are carried out to verify the effectiveness of proposed strategy.

• 동의생리병리학회지
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• 제18권6호
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• pp.1869-1880
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• 2004

In the oriental medicine, a mixture of herbs has been commonly used as important components to control allergic and inflammatory diseases. In the present study, we prepared a mixture of Dictamni Radicis Cortex(Baiksunpee), Houttuyniae Herba(Uhsungcho), and Aurantii Immaturus Fructus(Jisil) to examine its anti-allergic effects in activated mouse splenic cells and found that Mix-1 is involved in regulating levels of B cell activating factors (CD23 and CD11a), IL-1β, IL-6, IL-10, TNF-α, and 1gE as well as HRF expression. It was observed that Mix-1 did not have cytotoxic effects on mLFC. Mix-1 showed inhibition of CD23 and CD11 alpaha expression in mouse B cells, and also decreased the production of IL-6, TNF-α, and 1gE. Both RT-PCR and ELISA analyses indicated that IL-6 and TNF alpha production were regulated at the gene expression level. In contrast, IL-10 mRNA and protein levels were increased in activated B cells by Mix-1 treatment. We also found that Mix-1 inhibited B cell proliferation and inhibited histamine releasing factor(HRF) expression, suggesting its inhibitory effect on histamine secretion. These data indicated that Mix-1 has an anti-allergic effect in activated macrophages and further suggest the possible application of Mix-1 as a therapeutic agent for the treatment of allergy-related diseases.

• 에너지공학
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• 제15권1호
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• pp.45-51
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• 2006

본 연구에서는 LFG와 LNG의 혼합연료의 연소가스측 열전달 특성을 LFG, LNG 단독 연료와 비교함으로써 실험적으로 연구하였다. 실험을 위하여 파일럿 연소시스템을 제작하였으며, 연소시스템의 열교환부에는 수직 수평 배플을 가지는 다관형 열교환기를 설치하였다. 실험은 연료 주입 방식, 저위발열량, 메탄의 조성(44.5%, 54.5%)의 서로 다른 조건에서 수행되었다. 본 연구를 통하여 동일한 레이놀즈 수에서 LNG의 연소가스측누셀트 수는 LFG보다 큼을 알 수 있었으며, LFG의 경우에 LFG와 LNG 혼합 연료가 LFC 단독 연료보다 큼을 확인하였다. 따라서, LFG를 사용하는 경우 LFG 단독 연료를 사용하기보다는 LFG에 LNG를 적절히 첨가시켜 사용하는 것이 열전달이 향상되며, 발생 LFG의 공급 불안정성을 완화하는데 기여할 수 있다고 판단된다.

• 한국수정란이식학회지
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• 제17권2호
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• pp.109-115
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• 2002

The present study was conducted for the production of transgenic cloned cows those secrete human lactoferricin into milk by somatic cell nuclear transfer (NT). To estimate detrimental effects of gene transfection on transgenic cloned embryo production, development rates of NT embryos were compared between transfected and non-transfected cumulus and ear fibroblast cells. An expression plasmid for human lactofericin (pbeta-LFC) was constructed by inserting a bovine beta-casein promoter, a green fluorescent protein (GFP) marker gene, and human lactoferricin target gene into a pcDNA3 plasmid. Two bovine somatic cell lines (cumulus cell and ear fibroblast) were established and transfected with the expression plasmid using a liposomal transfection reagent, Fugene6 as a carrier. Cumulus cell and ear fibroblast were transfected at the passage of 2 to 4, trypsinized and GFP-expressing cells were randomly selected and used for somatic cell NT. Developmental competences (rates of fusion, cleavage, and blastocyst formation) in bovine transgenic somatic cell NT embryos reconstructed with non-transfectecd cells were significantly higher than those from transfected cells in cumulus cell and ear fibroblast (P＜0.05). This study indicated that transfection of done. cell has detrimental effect on embryo development in bovine transgenic NT.