• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.188-190
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• 2006

This paper describes the effects of air gap eccentricity in induction machines. Asymmetric electro-magnetic force caused by the frictional worn bearing, rotor misalignment and unbalanced rotor etc. generates an asymmetrical operation, vibration and electro-magnetic noise. The need for detection of these rotor eccentricities has pushed the development of monitoring methods with increasing sensitivity and noise immunity. In this paper, we focus on investigating the asymmetrical operation considering of unbalanced magnetic force in squirrel-cage induction motor with 380 [V], 7.5 [kW], 4P, 1,768 [rpm]. The effects of the rotor eccentricity, magnetic force are investigated by finite element method (FEM).

• Journal of Plant Biology
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• 제8권1_2호
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• pp.1-4
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• 1965

Beta-ray irradiation effects on structural changes of the chromosomes in root tip of rye, Secale cereale L., seedlings, particularly the frequency of chromosome bridge induction at anaphase stage treated with radioactive sulfur (S35) solutions were studied in this experiment. Among the four different concentrations of isotope solution, the lowest one, 0.4$\mu$c solution, has shown weak effect on the induction of chromosome aberration. On the other hand, higher concentration, 25.6$\mu$c solution, induced higher frequency of chromosome bridge induction as much as 4.3%. Concerning the relationship between the ages of after treatment and the ranges of concentration, the higher concentrations showed more pronounced effects than the lower ones.

• 한국정밀공학회지
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• 제19권6호
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• pp.136-144
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• 2002

Melting method has long been considered difficult to realize because of problems such as the low foamability of molten metal, the varying size of cellular structures and solidification shrinkage. The parameters to solve the problem in electric furnace were stirring temperature, stirring velocity, heating velocity and foaming temperature It is important to consider the effects of induction heating, because it brings about the inner flow by the temperature gradient. Aspect ratio also depends on the induction heating. Mechanical properties are dependent on cell sizes and aspect rations. Therefore, this paper presents the effects of these parameters on the cell sizes. For the sake of this, combined stirring process was used to fabricate aluminum foam materials by the above mentioned parameters. Image analysis was performed to calculate the cell sizes, distributions, and aspect ratioes at the cross section of feared aluminum in the direction of height.

• Archives of Pharmacal Research
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• 제20권3호
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• pp.234-238
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• 1997

CINC-1 is a member of chemokine family with chemotactic and activating properties to neutrophils. CINC-1 induction in IL-$1{\beta}$-stimulated rat fibroblast NRK-49F cells was quantitated by a sensitive ELISA. CINC-1 production was increased up to 135 ng/ml from basal 2-6 ng/ml by stimulation with IL-$1{\beta}$.Steroidal anti-inflammatory drugs including dexamethasone and prednisolone exhibited potent suppressive effects on IL-$1{\beta}$-induced CINC-1 production. Among 39 kinds of natural triterpenoids tested, acacigenin B exhibited the highest suppressive effects with about $10{\mu}M$ to be 50% of inhibition on the CINC-1 induction. The suppressive potency of acacigenin B on IL-$1{\beta}$induced CINC-1 production was about 10-fold less than that of the steroidal anti-inflammatory drugs.

• 대한한방부인과학회지
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• 제24권3호
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• pp.28-47
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• 2011

Objectives: This study was performed to investigate the effects of Angelicae gigantis Radix (AGR) which is one of the most useful herbal-drug to treat patients with Polycystic Ovary Syndrome (PCOS) in Oriental medicine on gene expression of ovary tissue. Methods: The effects of AGR on gene expression of ovary tissue resected from PCOS induced rats using single injection of $\ss$-Estradiol 17-valerate (EV) was measured using microarray technique, and the functional analysis on these genes was conducted. Results: Total 2,812 genes were up-regulated or down-regulated, 1,421 genes were up-regulated, 1,391 genes were down-regulated by induction of PCOS. Up-regulated genes were mainly involved in biological function such as cell signalling pathways and inflammatory response. Expression levels of 1,442 genes were restored to those of naive animals by administration of AGR. 558 genes were restored to those of naive animals, which were lowered by induction of PCOS. 884 genes were lowered to naive levels, which were elevated by induction of PCOS. The functions of restored genes were partially involved in the restoration of expression levels, which were changed by induction of PCOS. Especially, up-regulated gene by induction of PCOS were mainly involved in these changes. These results mean restorative effects of AGR on damaged functions by induction of PCOS. The network of total protein interactions was measured using cytoscape program, and some key molecules, such as IRS2, MCM10, ORC2L related in up-regulated genes, CTBP2, CD44, RHOA, related in down-regulated genes that can be used for elucidation of therapeutical mechanism of medicine in future were identified. Conclusion: Restored genes by AGR were thought to have common pathways related in regulation of gene expressions. Especially, genes in restored expression levels by AGR, which were up-regulated by induction of PCOS, were regulated by 9 of common transcription factors, genes in restored expression levels by AGR, which were down-regulated by induction of PCOS, were involved in 25 of common transcription factors.

• Current Research on Agriculture and Life Sciences
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• 제18권
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• pp.1-7
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• 2000

본 실험은 식물조직배양 기법을 통하여 한란과 심비디움의 효율적인 증식을 위한 식물 생장조절물질의 적정 처리방법을 구명하고자 수행하였다. 한란의 rhizome 형성은 무처리 및 10 ppm kinetin + 2 ppm NAA, 심비디움의 protocorm 형성은 무처리 및 10 ppm kinetin + 0.05 ppm NAA에서 아주 양호하였다. Callus 유도의 적정 식물 생장조절물질의 농도는 구명하지 못했다. 한란 rhizome으로부터의 shoot 분화에는 10 ppm BA + 2 ppm NAA, 5 ppm BA + 2ppm NAA, 심비디움 protocorm으로부터의 shoot 분화는 10 ppm Kinetin + 0.05 ppm NAA, 1 ppm Kinetin + 2 ppm NAA에서 비교적 효과적인 것으로 나타났다.

• 한국가축번식학회지
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• 제16권3호
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• pp.231-237
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• 1992

The effects to the corticosteroid dexamethasone(DEX) and(or) estradiol-benzoate(E-B) treated to induction of parturition and birth weights of the young was conducted in 48 pregnant Korean native goats. The animals were divided into 4 goats per each treatment by the time(142, 145 and 148 day of pregnancy) and dosage(DEX 15, 20mg, DEX 8mg＋E-B 10mg and DEX 13mg＋E-B 7.5mg per goat). The results obtained were summarized as follows: 1 The time for induction of parturtion after DEX(15, 20mg) treatment on day 148 of pregnancy was significantly(P<0.01) shorter than 142 and 145 days. There was no significant difference each dosage of DEX on same day of pregnancy. 2. The addition of E-B to DEX treatment compared with DEX alone group at day 142 and 145 of pregnancy were significantly(P<0.01) shorter the time for induction of parturition. However, treatment with DEX along or with E-B on 148 day of pregnancy did not affect the time to induction(about 27 hrs) of parturition between each treatment. 3. The birth weight of kids after parturition was heaviest(P<0.01) on day 148 of pregnancy. However, development and vigor of kids were not significant different between DEX alone treatment and with E-B.

• 동의생리병리학회지
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• 제25권2호
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• pp.257-263
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• 2011

This study was designed to investigate the effects of Hominis placenta pharmacopuncture treatment and electroacupuncture therapy on the functional recovery and histological change, protein expression in spinal cord injury(SCI) rats. Experimental groups were divided into the Group I(normal control rat), Group II(Non-treatment after spinal cord injury induction), Group III(Hominis placenta pharmacopuncture treatment after SCI induction), Group IV (Electroacupuncture therapy after SCI induction), Group V(Hominis placenta pharmacopuncture treatment and electroacupuncture therapy after SCI induction). After operation, rats were tested at modified Tarlov test at 1 to 3 days with divided into 4 groups, and motor behavior test(BBB locomotor rating scale, Grid walk test) was examined at 3, 7, 14, and 21 days. For the observation of damage change and size of the organized surface in muscle and spinal cord, histopathological studies were performed at 21 days by H & E stain, and BDNF & NT-3 protein expression studies were performed at 21 days. Acco rding to the results, Hominis placenta pharmacopuncture treatment and electroacupuncture therapy can play a role in facilitating recovery of locomotion following spinal cord injury. Specially, Hominis placenta pharmacopuncture treatment and electroacupuncture combimed therapy after SCI induction was most improvement in functional recovery, BDNF, and NT-3 protein synthesis.

• Tribology and Lubricants
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• 제34권6호
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• pp.284-291
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• 2018

Ball-milling for reactant powders in advance and using an induction heating system for Ni-Al intermetallic coating process are known to enhance the reactivity of combustion synthesis. In this work, the effects of the charging weight ratio of ball to powder in ball-milling for reactant Ni-Al powders and the synthesizing temperature in induction heating on sliding wear behavior of the coating layers are investigated. Sliding wear behavior of the coating layers is examined against a tool steel using a pin-on-disc type sliding wear machine. As results, wear of the coating layer ball-milled without ball was severely worn out at the sliding speed of 2m/s, regardless of the synthesizing temperature in induction heating. However, the wear rate of the coating layers at the sliding speed was remarkably decreased with increasing the charging weight ratio of ball in ball-milling for reactant powders. This can be explained by the fact that the void in the coating layer is disappeared and the coating layer is densified by the ball-milling. The evidence showed that pitting damages were disappeared on the worn surface of ball-milled coating layer. Consequentially, the Ni-Al intermetallic coating layer could have better wear resistance at all sliding speed ranges with the ball-milling for reactant powders in advance.

• 전기학회논문지P
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• 제57권3호
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• pp.225-230
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• 2008

Reactor starting method has the advantage of simplicity and closed transition in spite of lower starting torque per kVA. This method allows a smooth start with almost no observable disturbance on transition and is suitable for applications such as centrifugal pumps or fans. Reactive power doesn't contribute to work but needs to sustain the electromagnetic field required for the induction motor to operate. Starting power factor of induction motor is specially lower than running power factor. Power factor application is needed to compensate for the lower power factor of induction motor. This power factor compensation systems is occasionally being hit by the effects of the starting reactor connection position at the starting, stopping of high-voltage induction motor. This paper describes voltage and current stress affected by the installation position of power factor compensation application at the reactor starting method.