• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.42_43
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• 2009

Ferroresonance is a resonance condition between a nonlinear iron core of a potential transformer (PT) and a capacitance. It can lead to PT voltages several times the normal equipment ratings, and cause the isolation broken and damage to equipments near the PT. This paper proposes a analysis method of PT ferroresonance in the time domain. Based on the simplified equivalent circuit, a differential equation was found and the flux was calculated when ferroresonance generates. The forced response and natural response were also analyzed. The performance of proposed analysis method was verified with the EMTP-RV generated data. The method can help analysis chaotic ferroresonance and periodic ferroresonance.

• Journal of Ginseng Research
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• 제18권2호
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• pp.113-117
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• 1994

To assess a polential relationship of Korean ginseng to allergic reactions, the effect of Korean ginseng on the total IgE in serum as an allergologic parameter was investigated in humans. Serum total IgE levels were measured in 8 subjects who have been taking ginseng for more than 5 years, 4 subjects of weak constitution, 10 newly hired workers in the ginseng processing industry and 7 normal subjects unexposed to Korean ginseng as control group. Blood samples were taken before and after the exposure to Korean ginseng. Total IgE levels after the exposure to Korean ginseng were not significantly different from those before the exposure within each group. And also, the IgE levels of control subjects were not significantly different compared with those of other groups. These results suggest that the exposure to Korean ginseng dose not affect significantly the IgE immune response of the subjects.

• 대한치과교정학회지
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• 제11권2호
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• pp.65-70
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• 1981

In the present study orthodontic force was applied to the molars of control group and experimental group treated with the lathyrogen beta-aminopropionitrile (BAPN). Observation resulted in the following conclusions : 1) New alveolar bone formation in response to orthodontic force in BAPN-treated rats exceeded corresponding bone formation in control of cup when measured at two tension sites in the periodontal ligament. 2) BAPN administration produced disorganization of the collagenous fibers of the periodontium of experimental group. Multiple eosinophilic cell-free areas were found distributed throughout the radicular portions of affected periodontal ligaments. 3) The areas of periodontium surrounding orthodontically treated teeth exhibited relatively normal organization under these conditions, while the periodontium of adjacent nonorthodontically treated teeth was disorganized. 4) The present results suggest that the typical histologic response to orthodontic force application can occur in the presence of a chemically and physically altered periodontium.

• 대한치과의사협회지
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• 제21권5호통권168호
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• pp.415-423
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• 1983

A total of 202 full coverage crowns from 31 patients was investigated to find out the relationships between crown contour and gingival response. Every experimental crown has its contralateral natural tooth for its control group. Gingival Index and buccolingual width of the crowns were measured on both experimental and control group. Following conclusions were obtained from the study. 1. Most of the crown restorations were overcontoured and the increments were servere at cervical and height of contour area. 2. Height of contour and contact point of the restored crown were located near cervical area. Besides, most crowns had narrow embrasure with wide contact area. 3. Gingival Index around crown restorations was significantly larger than that of control group. 4. the interrelationship between Gingival Index and restored material or restored period was not verified at 5% significant level. 5. When grouping the artificial crowns into overcontoured, normal contoured, and undercontoured group by their width increment, the gingival inflammation was the severest in the overcontoured group and the mildest in the undercontoured group.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.203-203
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• 2010

The proton exchange membrane fuel cell (PEMFC) is different from the normal power supply, and it is a nonlinear, multi-input, strong coupling, the complex dynamic system with large time delay. At present, many studies on the content of the fuel cell fuel cells focus on a static process, this paper analyzed in subsequent sections of the process of fuel cell dynamic response time of transition, and then it found the method to reduce the response time during the process of load change to ensure that the stability of output power.

• 한국생산제조학회지
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• 제24권2호
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• pp.211-216
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• 2015

Recently, because of the growth in the leisure industry and interest in health, the demand for bicycles has increased. In this research, considering the vertical load on a bike frame under static state conditions, the deflection and mass of the bike frame were minimized by satisfying the service condition and performing optimization. The thickness of the bicycle-frame tube was set to a design variable, and its sensitivity was confirmed by an analysis of means (ANOM). To optimize the solution, a response-surface-method (RSM) model was constructed using D-Optimal and central composite design(CCD). The optimization was performed using a non-dominant sorting genetic algorithm (NSGA-II), and the optimal solution was verified by finite-element analysis.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계 학술대회논문집(수송기계편)
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• pp.85-89
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• 2005

For the analysis of a vibrating two dimensional structure such as the simply supported rectangular plate, Spectral Finite Element Method (SFEM) has been studied. Under the condition that two parallel edges are simply supported at least and the other two edges can be arbitrary, Spectral Finite Element has been developed. Using this element SFEM is applied to the vibrating rectangular plate which all edges are simply supported, and obtain the frequency response function in frequency domain and the dynamic response in time domain. To evaluate these results normal mode method and finite element method (FEM) are also accomplished and compared. It is seen that SFEM is more powerful analysis tool than FEM in high frequency range.

• 한국가금학회지
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• 제15권2호
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• pp.67-71
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• 1988

백색 Leghorn 암탉의 난자생성과정 중 감수분열을 억제하여 2배수성 난자(2n)의 생산에 근거한 다배교성 가축생산과 능력개양의 기초연구인 본 실험에서 감수분열시기는 배난 전 2~4시간이고 이때에 체중 kg당 0.3mg의 TEM(Tri ethylene melamin)을 복강에 주입하여 수정율 38%의 계란을 얻었고 이들 중 66%가 TEM의 영향으로 2n 의 난자가 생성되어 정상정자와의 결합으로 3배수성(3n)의 배아로 나타났다.

• 대한자기공명의과학회:학술대회논문집
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• 대한자기공명의과학회 2003년도 제8차 학술대회 초록집
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• pp.85-85
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• 2003

Purpose： To investigate whether or not acupuncture of GB34 produces a significant response of the modulation of somatomotor areas by functional magnetic resonance imaging (fMRI) study. Materials and methods： The acupoint, GB34, located in the back of the knee, is known to be effective in recovering motor function after stroke. Using 3T MRI scanner, functional MR imaging of the whole brain was peformed in 12 normal healthy subjects during two stimulation paradigms; acupuncture manipulation on GB34 and sham points. This study investigates the activation of the motor cortex elicited by a soft and an intensified stimulation of GB 34.Three different paradigms were carried out to detect any possible modulation of the Blood Oxygenation Level Dependent (BOLD) response in the somatomortor area to motor stimulation through acupuncture.

• 대한한방소아과학회지
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• 제14권2호
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• pp.85-96
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• 2000

Objectives : This experimental study was designed to investigate the effects of hormone changes in the rats with muscle atrophy in response to Strychnos nuxvonica L. Methods : 24 male rats with muscle atropht by hindlimb suspension method as experimental group and 6 normal male rats were used. Experimental group was administered Strychnos nuxvonica L. 3 times a day, 1mg/kg per one dosage P,O, After 2 to 4 weeks hormone changes in blood were analysed. Results and Conclusions : Norepinephrine and Epinephrine level in blood as they act neurotransmitting substances were significantly increased by administering Strychnos nuxvonica L.