• 한국수산과학회지
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• 제28권6호
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• pp.793-804
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• 1995

Polychaetous community survey in Tomioka Bay was carried out 5 times seasonally from May 1991 to March 1992 by quantitative grab sampling (0.05m2) at 11 stations. Based on the granulometric composition and environmental factors, a homogeneous soft bottom was found in St.5-10. The species of the polychaete were classified into three feeding groups using the Fauchald and Jumars' feeding guild system. According to polychaetous community composition data, deposit feeders predominate in sandy silt area where the silt-clay content is $60-69.3\%.$ These deposit feeders were subdivided into surface deposit feeders and subsurface deposit feeders by their living position and mode. Also, suspension feeding group comes as the third dominant group. Seasonal changes of each feeding group were described in terms of numerical density and biomass. Feeding layer and types of dominant species (Lumbrineris longifolia: surface deposit feeder; Praxillella pacifica: subsurface deposit feeder; Chone duneri; suspension filter feeder, etc.) were examined in the intact sediment core samples. Also, longterm density change among the three dominant species during 10 years was disussed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 A
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• pp.85-87
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• 1994

Feeding biological cells one by one is the key point in the manipulation of cells. The conventional valve systems have many difficulties in feeding cells one by one, because they shut the whole flow of fluids when they are closed and have possibilities of breaking the fragile cells. They need some other equipments for continuous supply of suspension and to protect the cells. We design a check valve for feeding biological cells one by one using polyimide all the silicon substrate. The cells are fed by hydraulic pressure through the isotropically etched cavity. When the suspension flows continuously along the channel the valve is bent by hydraulic pressure and a cell is fed to the outlet. We have studied a cell fusion device fabricated with polyimide and electroplating. If the designed check valve is located in front of the cell fusion device it is helpful to fuse two different kinds of cells.

• KSBB Journal
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• 제8권5호
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• pp.488-494
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• 1993

본 연구에서는 캘리포니아 양귀비(Eschscholtzia californica) 현탁배양세포의 주요 이차대사산물인 benzophenanthridine alkaloid의 생성을 증가시키기 위해 생합성 전구체인 tyrosine, tyramine, dopamine 그리고 L-dopa를 exponential phase 말기에 투여하였다. 그리고 이때 yeast elicitor와 전구체를 동시에 투여한 것과 비교하여 보았다. 그 결과 적당량의 전구체 투여시 benzophenanthridine alkaloid의 생성은 대조구(무처리)에 비해 증가하였다. 그리고 elicitor와 전구체를 동시에 투여해 주었을 때 대조구(elicitor만 처리)에 비해 상당히 증가하였는데, 이것은 elicitor에 의해 유도된 이차대사 관련 효소에 의해 전구체의 biotransformation이 촉진된 것이라 생각된다. 이와 같이 전구체 투여에 의해 이차대사산물의 생성을 증가시키려 할 때 전구체만 투여하는 것보다는 촉진제를 동시에 투여함으로써 최종산물의 생성을 극대화시킬 수 있으리라 생각되며, 식물세포배양의 산업화에 유용하게 이용되리라 생각된다.

• Journal of Power Electronics
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• 제16권1호
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• pp.111-120
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• 2016

Generally, a single phase H-bridge converter feeding a single primary track is employed in conventional inductive power transfer systems. However, these systems may not be suitable for some high power applications due to the constraints of the semiconductor switches and the cost. To resolve this problem, a novel dual coupled primary tracks IPT system consisting of two high frequency resonant inverters feeding the tracks is presented in this paper. The primary tracks are wound around an E-shape ferrite core in parallel which enhances the magnetic flux around the tracks. The mutual inductance of the coupled tracks is utilized to achieve adjustable power sharing between the inverters by configuring the additional resonant capacitors. The total transfer power can be continuously regulated by altering the pulse width of the inverters' output voltage with the phase shift control approach. In addition, the system's efficiency and the control strategy are provided to analyze the characteristic of the proposed IPT system. An experimental setup with total power of 1.4kW is employed to verify the proposed system under power ratios of 1:1 and 1:2 with a transfer efficiency up to 88.7%. The results verify the performance of the proposed system.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 춘계학술대회 논문집
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• pp.205-208
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• 2008

Generally, there are several types in rear suspension. The rear suspension of subframe type consisting of side member and front/rear cross member is widely used in a medium car and full car. In the small car case, the beam of tubular type without independent suspension system is used to reduce manufacturing cost. The optimized rear suspension of subframe type using hydroforming method has been developed in this study. In designing suspension, the driving stability and durability performance should be considered as an important factor. The stability is related to dynamic frequency and durability is connected with stress analysis of structure. We focus on increasing the stiffness of suspension and decreasing the maximum stress relating to durability cycle life. For making use of the merits of hydroforming which is possible to make the bead, tube expansion, and feeding in desiring position, several optimization design techniques such as shape, size, and topology optimization are proposed. This optimization scheme based on the sensitivity can provide distinguished performance improvement in using hydroforming. Through commercial software based on the finite element, the superiority of this design method is demonstrated.

• Journal of Microbiology and Biotechnology
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• 제8권3호
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• pp.237-244
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• 1998

A study was carried out to elucidate the relation between the production of flavonol glycosides and the change of phenylalanine ammonia-lyase activity in cell suspension cultures of Ginkgo biloba by the unassisted and synergistic effects of various factors. The quercetin production showed a mixed-growth-associated pattern in cell suspension cultures. Fluorescent light and UV radiation increased phenylalanine ammonia-lyase (PAL) activity, and resulted in the increase of the production of quercetin and kaempferol ten- and four-fold, respectively, as compared to that obtained in the normal culture condition. The cell growth of Ginkgo biloba was enhanced .at higher temperatures whereas the quercetin production was at its maximum at low temperatures. Moreover, the quercetin production was increased by temperature change during the culture period. In particular, the quercetin production was at the highest level when the culture temperature was elevated from $10^{\circ}C\;to\;30^{\circ}C$. The addition of phenylalanine as a precursor in the culture medium stimulated an 8-fold increase in the production of quercetin; the addition of naringenin caused a l0-fold increase. The quercetin production was also greatly increased by feeding enzyme cofactors such as 2-ketoglutarate and ascorbic acid in the culture medium, but specific PAL activity was not increased except with phenylalanine feeding. The synergistic effect of UV radiation and naringenin feeding was observed, resulting in the increase of flavonol glycoside production at a rate higher than in any other case investigated.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.250-253
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• 2000

We researched effects of growth on initial inoculum size, liquid volume, and medium feeding rate etc. Cell suspension inoculated at low cell concentrations showed a typical growth reduction, whereas root cultures showed an improvement in growth. In this paper, Hairy roots showed high growth rate at 0.4 % inoculum size and 100 mL liquid volume in 250 mL flask cultures.

• Applied Biological Chemistry
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• 제36권5호
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• pp.358-363
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• 1993

박하(Mentha piperita) 세포현탁배양에(-)-menthol 생합성 중간체를 투여하여 배양된 세포의 대사경로를 연구하였다. (-)-Limonene을 투여 하였을 때 이는 다른 대사물로 변환되지 않는 것으로 관찰 되었다. (+)-Pulegone은 (+)-isomenthone 및 (-)-menthone으로 변환되었으며, (-)-menthone은 (-)-menthol로 변환되었다. 이 실험은 현탁배양세포가 대부분의 생합성 활성을 유지하고 있으며 (-)-limonene hydroxylase의 활성이 제한적임을 보여 주었다. (-)-Isopiperitenone을 투여하였을 때는 (+)-pulegone, piperitenone, (-)-7-hydroxyisopiperitenone, (R)- 및 (S)-6-hydroxyisopiperitenone이 생성되었다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권6호
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• pp.331-334
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• 2002

Culture conductivity and on-line NADH fluorescence were used to measure cellular growth in plant cell suspension cultures of Podophyllum hexandrum. An inverse correlation between dry cell weight and medium conductivity was observed during shake flask cultivation. A linear relationship between dry cell weight and culture NADH fluorescence was obtained during the exponential phase of batch cultivation In a bioreactor under the pH stat (pH 6) conditions. It was observed that conductivity measurement were suitable for biomass characterisation under highly dynamic uncontrolled shake flask cultivation conditions. However, if the acid/alkali feeding is done for pH control the conductivity measurement could not be applied. On the other hand the NADH fluorescence measurement allowed online-in situ biomass monitoring of rather heterogenous plant cell suspension cultures in bioreactor even under the most desirable pH stat conditions.

• 한국임상수의학회지
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• 제17권2호
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• pp.411-415
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• 2000

For comparison with conventional barium-gastrointestinal study, modified method using barium and methylcellulose was performed in 16 normal dogs (4-8 kg) divided into two groups. The group 1 received 8ml/kg of 40% w/v barium suspension only, and group 2 had taken 15 ml/kg of 0.6% w/v methylcellulose after administration 4 ml/kg of 40% w/v barium suspension by feeding tube. The barium suspension was prepared mixing full strength-barium suspension with water and methylcellulose solution was produced by blending methylcellulose sterilized water Sequential radiographs, lateral and ventrodorsal projections were obtained at 5 minute, 20 minute,40 minute. 60 minute and every 30 minutes thereafter, until the contrast is seen in the large intestine Inage qual- ity was rated by three veterinary radiologists as " poor" " fair ". "good", or "excellent" We analyzed the relationship between image quality,, transit time. Between two techniques, the modified method with 4ml of 40% w/v barium suspension and 15 ml of 0.6% w/v methylcellulose showed much better image quality ["excellent" result in 7 of the 8 subjects (88%)] and shorter transit time (107 minutes) toe the cecum. In addition, the best image quality was obtained at 20 and 40 minutes after admin-istration of contrast agent. It call be concluded the modified gastrointestinal study using methylcel-lulose after administration of barium suspension was a simple technique and easily improved the image quality and diagnostic accuracy of gstrointestinal disorders in small animal.racy of gstrointestinal disorders in small animal.