• Journal of Microbiology and Biotechnology
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• v.5 no.4
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• pp.229-233
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• 1995

Acremonium chrysogenum was immobilized in ionotropic gel beads to develop semi-continuous production of cephalosporin C (CPC). Barium alginate beads were more stable than calcium alginate or strontium alginate beads in chemically defined media. The gel stability of Ba-alginate was further increased by cross-linking with polyethyleneimine (PEI). The presence of carboxymethyl cellulose inside Ba-alginate beads did not reduce mass transfer resistance. Ba-alginate microbeads that had little diffusion limitation increased CPC production rate 1.6 fold higher than that of normal beads. CPC fermentation with immobilized cells in Ba-alginate microbeads was performed continuously for 40 days by way of repeated fed-batch operations. Mathematical modeling was developed to describe the repeated fed-batch fermentation system. Results of the computer simulation agreed well with the experimental data, which made it possible to predict an optimal feeding rate that could maximize total CPC productions.

• Journal of Microbiology and Biotechnology
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• v.9 no.5
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• pp.554-561
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• 1999

A novel estimation method was investigated for determining the concentrations of residual biomass, poly-3-hydroxybutyrate (PHB), and main nutrients including carbon and nitrogen sources, phosphate, and mineral ions from the supplied amount of ammonia solution used for a pH-control solution and nitrogen source in a PHB fermentation. The estimation equations for a batch culture and a fed-batch culture were derived from the relationship between the growth rate of residual biomass and the feed rate of the pH-control solution, and then were applied to the batch culture and the fed-batch cultures of Alcaligenes latus. This method was successfully applied to estimate the concentrations of residual biomass, PHB, and nutrients.

• Korean Management Science Review
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• v.11 no.1
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• pp.145-163
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• 1994

For an Information System to be successful the continual control of the database system(DBS) is very important. In general, such control operations are performed periodically in batches, even in real time systems. We explain DBS related such control operations and describe the decision problem in each of them. Specifically, backup, checkpointing, reorganization, and batch update operations are considered. Then we develop a general model of the batch backup situation to determine the optimal backup timing. Other operations are considered as special cases of the general batch backup operation are derived and compared. We show that, in general, the control limit policy is superior to the fixed time interval policy in terms of the long-run average cost per unit time. Some practical considerations about the implementation of optimal policies are also mentioned.

• Management Science and Financial Engineering
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• v.9 no.2
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• pp.47-68
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• 2003

We consider the customer order scheduling problem with job capacity restriction where the number of jobs in the shop at the same time is fixed. In the customer order scheduling problem, each job is part of some batch (customer order) and the composition of the jobs (product) in the batch is pre-specified. The objective function is associated with the completion time of the batches instead of the completion time of the jobs. We first summarize the known results for the general customer order scheduling problems. Then, we establish some new properties for the problems with job capacity restriction. For the case of unit processing time with the objective of minimizing makespan, we develop a polynomial-time optimal procedure for the two machine case. For the same problem with a variation of no batch alternation, we also develop a polynomial-time optimal procedure. Then, we show that the problems with the objectives of minimizing makespan and minimizing average batch completion time become NP-hard when there exist arbitrary number of machines. Finally, We propose optimal solution procedures for some special cases.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.5
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• pp.291-293
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• 2003

Batch reactors were employed to investigate the kinetics of cellulose hydrolysis under extremely low acid (ELA) and high temperature condition. The sawdust was pretreated by Auto-hydrolysis prior to the batch reaction. The maximum yield of glucose obtained from the batch reactor experiment was about 70% for the pretreated sawdust, this occurred at 210 and 22$0^{\circ}C$. The maximum glucose yield from the untreated sawdust was much lower at these temperatures, about 55%. The maximum yields of glucose from the lignocellulosics were obtained between 15th and 20th minutes after which gradual decrease was observed.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05a
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• pp.753-758
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• 1995

중수로 압력관용 Zr신합금을 개발하기 위하여 Batch 1(63종), Batch 2(33종), 및 Batch 3(33종)의 지르코늄합금을 설계, 제조하여 이들 합금에 대한 특성평가를 실시하였다. 설계합금은 고진공 전자빔 용해(Electron Beam Remelting), 단조(95$0^{\circ}C$), $\beta$열처리, 중간열처리, 냉간압연 및 진공열처리의 일관된 제조공정을 거쳐서 판상으로 제조되었다. 설계합금의 특성평가로 성분분석, 인장시험, 부식시험, 충격에너지시험 및 미세조직분석이 수행되었으며, Batchl-Batch3의 120여종의 지르코늄합금에 대한 특성을 종합적으로 평가하여 내부식성 및 고강도 특성의 7종 지르코늄합금을 선정하였다.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.3
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• pp.95-102
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• 2012

It is not easy to establish the correct standard time and standard manhour in a process of small quantity batch production system, especially in a case of irregular quantity of production. Therefore, how to establish rational standard time about manufacturing process of a power cable company which is representative business for small quantity batch production system will be suggested in this paper. Furthermore, how to establish standard manhour which can be used for effective control of labor productivity will also be presented.

• Journal of Microbiology and Biotechnology
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• v.12 no.4
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• pp.617-621
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• 2002

In order to optimize the carrot hairy root culture for SOD production, a fed-batch culture of hairy roots was performed in a bioreactor. Maximum SOD activity was obtained when the hairy roots were transferred to the MS medium containing 110 g/1 concentration of sucrose. By controlling the sucrose concentration (70 g/1 sucrose for growth and 110 g/1 sucrose far production, respectively) In a two-stage fed-batch culture, 29 g/1 of the hairy roots was obtained based on the final dry mass. The volumetrically determined SOD activity and productivity in the fed-batch culture were about 6 times higher than those from the flask culture containing sucrose at 30 g/1 concentration.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.845-848
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• 2008

In this study, through the Batch Plant in field which is carrying out in the country, this research is going to grope the development of Ready-mixed Shotcrete that can improve the construction of shotcrete, and long-term durability. Accordingly, in this study, the Batch Plant in field which is only for shotcrete will be chosen in random so that can be aware the problems of the Batch Plant in field, and when the results come out, the shotcrete system will be prepared that is based on the results of rsearch, and also can be used in preparation index of shotcrete. Moreover, the results will be able to improve an efficent tool that can increase shotcrete quality.

• Journal of the Korean Ceramic Society
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• v.15 no.4
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• pp.185-192
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• 1978

The effects of slag prticle size, $Na_2SO_4$ addition and sulphide in slag to the foam formation was investigated. This investigation showed that the slag particle size and the amount of $Na_2O$ had produced effects on the size of the foam, foam distribution and firing temperatures. In addition to that the amount of sulphide loss during the firing was controlling factor for the foam formation. The smaller slag particles and higher firing temperatures increased the loss of sulphide in the slag. The addition of $Na_2SO_4$ in the slag batch was likely to inhibit the foam formation. The larger slag particles resutled in the larger foam size and tended to be increasing the batch firing temperature. The main constituents of slag formed glass consisted of wallstonite and glassy phase. It is believed that the controlling the slag particle size and the amount of $Na_2SO_4$ in the slag batch will probably be main factors in foam formation.