• Journal of Environmental Health Sciences
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• v.20 no.2
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• pp.28-38
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• 1994

New problems have been recently posed on the abnormal foaming (Scum) in an aeration tank and the sludge flotation in a final sedimentation tank during the activated sludge process. However, the activities of the causing bacteria, Nocardia-amarae in an aeration tank have not been searched out at all. Therefore, in this article the activities of Nocardia-amarae in an aeration tank have been closely examined by means of the changes of (F/M) ratio, SRT and inflowing substrate using continuous type and fed-batch type. Summarized results of experiments are as follows. 1. Regrading continuous culture when synthetic wastewater was used substrate neither the increase in the number of Nocardia-amarae in the aeration tank nor the Occurrence of Scum was observed. 2. In the case of fed-batch culture, Nocardia-amarae in the aeration tank increased due to the partial change in substrate and the effect of SRT was significant. 3. Once the scum was formed and the quantity of added Nocardia-amarae and substrate were not changed, the effect of STR was not significant.

• Journal of Sensor Science and Technology
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• v.14 no.1
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• pp.47-51
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• 2005

An active ${\mu}$-mixer is important in Bio-MEMS and ${\mu}$-TAS. The mixing state depends on some kinds of factors including the intensity of ultrasonic radiation. We have visualized the mixing state of the mixing chamber with radiation time and presented the influence of the driving voltage in this research. It will be possible to compare the performances of the ultrasonic radiation parts used in the active ${\mu}$-mixer using this method.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.701-702
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• 2000

The thiolated anti-Escherichia coli antibody prepared by thiolation with a thiolcleavable heterobifunctional cross-linker, sulfosuccinimidyl 6[3- (2-pyridyldithio) propionamido]hexanoate (sulfo-LC-SPDP) was chemisorped onto one gold electrode of the piezoelectric quartz crystal surface. In the QCM system employing a batch-type well holder, a steady-state frequency decrease was attained within 20 min when $100{\sim}200\;{\mu}L$ suspensions of Escherichia coli having viable cell counts of $10^5{\sim}10^6\;CFU/mL$ were added. The stability of sensor response was improved compared to the system with a batch-type dip holder.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.117-121
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• 2001

The present study has been conflicted to verify the applicability of tire powder and food waste compost as biofilter materials to degrade volatile organic compounds. Batch and column tests were performed to determine the optimum ratio of tire powder to compost and the appropriate mixing type of two materials for removal of the selected VOCs, i.e., benzene, ethylbenzene, PCE, and TCE. According to batch tests, tire powder and compost mixture had faster removal rate than the compost. The biofilter column filled with tire powder and compost showed better VOC removal efficiency than that filled with only tire powder. In this study, the best removal rate was observed in the sandwich type column test of which the tire : compost weight ratio was 1:2

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.05a
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• pp.303-306
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• 2005

본 연구는 개발한 batch type 동결농축장치를 이용하여 제조한 동결농축유의 일반성분 분석 및 이화학적 특성을 분석하고, 진공농축유와 비교하여 동결농축유의 우수성을 입증하기위하여 실시되었다. 동결농축유와 진공농축유는 농축방법에 따라 차이가 나타났으며, 전기영동 실험결과 진공농축유에 비하여 동결농축유의 band가 뚜렷하게 나타나 열처리한 진공농축유가 열변성이 된 것을 확인할 수 있었다. 열처리시에는 Maillard반응이 일어나거나 유효성 lysine함량이 감소되며, 유청내 용해성 칼슘이 인산이나 변성된 단백질과 결합하여 한외여과성칼슘(calcium ions in milk ultrafiltrates)함량이 감소되며, 비타민 손실, 유당의 이성체화, 휘발성 황화합물 생성에 의해 가열취가 발생될 수 있다. 따라서 전기영동 실험결과 batch type 동결농축장치를 이용하여 제조한 동결농축유의 우수성을 확인할 수 있었다.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.30 no.1
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• pp.33-40
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• 2007

A multi-server queueing system with finite buffer is considered. The input flow is the BMAP (Batch Markovian Arrival Process). The service time has the PH (Phase) type distribution. Customers from the BMAP enter the system according to the discipline of partial admission. Besides ordinary (positive) customers, the Markovian flow (MAP) of negative customers arrives to the system. A negative customer can delete an ordinary customer in service if the state of its PH-service process belongs to some given set. In opposite case the ordinary customer is considered to be protected of the effect of negative customers. The stationary distribution and the main performance measures of the considered queueing system are calculated.

• IE interfaces
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• v.19 no.1
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• pp.34-42
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• 2006

This paper presents a scheme for a hierarchical production scheduling and control system for a refrigerator factory with mixed model assembly lines. The setting of the factory is as follows. There are three mixed-model assembly lines called main line A, B and C and two batch lines that supply parts to the main lines. For each of the main lines, three work-centers are dedicated to them. The sub-lines and work-centers produce parts in batch type. An incoming production order from the master planner is characterized by its product type, amount, and due date. Under this situation, the proposed scheme has several features to schedule and control the above mentioned factory; 1) select the starting time and the place (assembly line) for an order processing, 2) devise a way to control orders to be processed as scheduled, and 3) reschedule orders when something unexpected happen. Finally, this paper provides a case study where the proposed scheme is applied to.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 1998.05a
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• pp.170-170
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• 1998

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.17 no.4
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• pp.299-306
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• 1988

• KSBB Journal
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• v.9 no.1
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• pp.48-54
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• 1994

A modified amidolytic assay and a fibrin plate method were used to accurately measure the concentration of single chain urokinase type plasminogen activator (scu-PA) and two-chain urokinase type plasminogen activator (tc-PA) in the spent media. $1.65{\times}10^6$(viable cells/ml) of maximum cell density and 1670(IU/ml) of scu-PA concentration were obtained in 1% serum containing medium. The overall conversion ratio from scu-PA to tc-PA was less than 10%. In the results of batch cultivation in a spinner vessel, $4.43{\times}10^6(total cells/ml)$ of maximum cell density and 1560(IU/ml) of scu-PA concentration was observed. The maximum scu-PA concentration and specific scu-PA Productivity were obtained in 1760(IU/ml) and $3.13{\times}10^{-4}(IU/cell)$, respectively, from perfusion cultivation. The conveysion ratios from batch, fed-batch and perfusion cultivations were less than 12%, which means that about 90% of scu-PA secreted from the cells can be maintained during the cultivations.