• ETRI Journal
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• 제38권2호
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• pp.397-404
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• 2016

In group-oriented applications, it is often required to verify a group of signatures/messages. The individual verification of signed messages in such applications comes at a high cost in terms of computations and time. To improve computational efficiency and to speed up the verification process, a batch verification technique is a good alternative to individual verification. Such a technique is useful in many real-world applications, such as mail servers, e-commerce, banking transactions, and so on. In this work, we propose a new, efficient identity-based signature (IDS) scheme supporting batch verifications. We prove that the proposed IDS scheme and its various types of batch verifications is tightly related to the Computational Diffie.Hellman problem under a random oracle paradigm. We compare the efficiency of the proposed scheme with related schemes that support batch verifications.

• 한국환경보건학회지
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• 제21권4호
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• pp.32-36
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• 1995

This study was carried out to investigate the treatment efficiency of sequencing batch reactor when the livestock nightsoil organic loading rate was varied. Sequencing batch reactor was operated with the variance of influent BOD concentration and operating cycle. The average influent BOD concentrations in this study were 150 mg/l, 200 mg/l, 250 mg/l, 300 mg/l, 350 mg/l, 400 mg/l, 450 mg/l and 500 mg/l in the condition of 1~3 cycles/day. The treatment efficiency of sequencing batch reactor is good at the volumetric loading of 0.05~0.20 kg $BOD/m^3\cdot day$. Therefore, sequencing batch reactor process would become an effective alternative for the process of small scale livestock nightsoil treatment plants.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.177-179
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• 2002

The process for the production of mannitol with fructose (5% to 25%) using Leuconostoc mesenteroides NRRL B-1149 was investigated. Optimization study for mannitol production was carried out in 8 liter batch or fed-batch cultures at $28^{\circ}C$, pH 5.0, without aeration. When 5% fructose was used in a batch culture fermentation, the yield of mannitol was 78% of theoretical. As the concentration of fructose was increased to 10% in a batch culture, the yield was reduced to 59.6% of theoretical. Using a fed-batch fermentation with 10% fructose, the yield was increased to 81.9%. When 15% fructose was used for a fed batch fermentation 5% fructose was initially added and the last 10% fructose was supplied continuously. The final yield of mannitol was 83.71% of theoretical. When 20% fructose was used, the yield was more higher, 89.48%.

• 대한산업공학회지
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• 제40권2호
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• pp.215-222
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• 2014

This paper provides a real-time loading strategy for batch processing machines in which a number of jobs are simultaneously processed as a batch. The batch processing machines can be seen in both manufacturing industries (e.g., semiconductor, automobile and metal working) and service industries (transportation vehicles, mail shipment and theme park). This paper focuses on batch processing machines in semiconductor manufacturing. We present a look-ahead loading strategy for tardiness minimization where future arrivals and due dates are taken into consideration. Simulation tests are performed on the presented strategy and some existing loading heuristics under various production settings with different traffic intensities and forecasting errors. Experimental results show that our strategy provides the performance of good quality.

• 한국축산시설환경학회지
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• 제13권3호
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• pp.219-232
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• 2007

Odors from manures are a major problem for livestock production. The most significant odorous compounds in animal manure a.e volatile fatty acids(VFAs). This work reviews the VFAs from the anaerobic sequencing biofilm batch reactor(ASBBR), anaerobic sequencing batch reactor(ASBR), solid compost batch reactor(SCBR), and aerobic sequencing batch reactor(SBR) associated with the animal manure biological treatment. First, we describe and quantify VFAs from animal manure biological treatment and discuss biofiltration for odor control. Then we review certain fundamentals aspects about Anaerobic and aerobic SBR, composting of animal manure, manure compost biofilter for odorous VFAs control, SBR for nitrogen removal, and ASBR for animal wastewater treatment systems considered important for the resource recovery and air quality. Finally, we present an overview for the future needs and current experience of the biological systems engineering for animal manure management and odor control.

• KSBB Journal
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• 제11권2호
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• pp.201-210
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• 1996

본 연구는 단일 탄소원인 포도당으로부터 PHA를 생산하는 공시균 Pseudomonas sp. HJ의 유가배양 을 검토함으로써, PHA 대량생산을 위한 기초자료 를 얻는데 그 목적을 두었으며 그 결과는 다음과 같다. U 발효조를 이용하여 배양시 교반속도 4 400rpm, 통기량 2vvm, 종균 배양시간 18 시간 및 종균 접종량 5%(v/v)일때 최적 생육을 나타내었다. 공시균 Pseudomonas sp. HJ는 용존산소의 결핍 에 의해서 PHA 축적율이 향상되지 않았으며, P PHA 생산단계에 충분한 수준으로 용존산소를 유지 시켜 주어야 함을 알 수 있었다. 공시균 Pseudomo­7 nas sp. HJ를 회분배양했을 때 24시간만에 $6.251g/\ell$의 건조균체량과 20% 의 PHA 축적율을 나타내었으며, constant feeding fed-batch culture로 배 양 45시간만에 최고$33.24g/\ell$의 건조균체량과 48.9%의 PHA 축적율을 나타내었다. 또한 intermit­t tent feeding fed-batch culture로 공시균 Pseu domonas sp. HJ를 배양했을때, 배양 45시간만에 $37.89g/\ell$의 건조균체량과 53.5%의 PHA 축적율을 나타내였다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권4호
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• pp.267-273
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• 2004

The optimization of culture conditions for the bacterium Pseudomonas aeruginosa BYK-2 KCTC 18012P, was performed to increase its rhamnolipid production. The optimum level for carbon, nitrogen sources, temperature and pH, for rhamnolipid production in a flask, were identified as 25 g/L fish oil, 0.01% (w/v) urea, 25 and pH 7.0, respectively. Optimum conditions for batch culture, using a 7-L jar fermentor, were 200 rpm of agitation speed and a 2.0 L/min aeration rate. Under the optimum conditions, on fish oil for 216 h, the final cell and rhamnolipid concentrations were 5.3 g/L and 17.0 g/L respectively. Fed-batch fermentation, with different feeding conditions, was carried out in order to increase, cell growth and rhamnolipid production by the Pseudomonas aeruginosa, BYK-2 KCTC 18012P. When 2.5 g of fish oil and 100 mL basal salts medium, containing 0.01 % (w/v) urea, were fed intermittently during the fermentation, the final cell and rhamnolipid concentrations at 264 h, were 6.1 and 22.7 g/L respectively. The fed-batch culture resulted in a 1.2-fold increase in the dry cell mass and a 1.3-fold increase in rhamnolipid production, compared to the production of the batch culture. The rhamnolipid production-substrate conversion factor (0.75 g/g) was higher than that of the batch culture (0.68 g/g).

• Food Science and Biotechnology
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• 제17권5호
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• pp.990-995
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• 2008

A thermostable $\alpha$-L-arabinofuranosidases ($\alpha$-L-AFase) is an industrially important enzyme for recovery of L-arabinose from hemicellulose. The recombinant $\alpha$-L-AFase from Thermotoga maritima was expressed in Escherichia coli by using a constitutive pHCE or an inducible pRSET vectors. In batch fermentation, the constitutive expression system resulted in slightly faster growth rate (0.78 vs. 0.74/hr) but lower enzyme activity (2,553 vs. 3,723 units/L) than those of the induction system. When fed-batch fermentation was performed, biomass and enzyme activity reached the highest levels of 36 g/L and 9,152 units/L, respectively. The fed batch cultures performed superior results than batch culture in terms of biomass yield (4.62-5.42 folds) and enzyme synthesis (3.39-4.00 folds). In addition, the fed-batch induction strategy at high cell density resulted in the best productivity in cell growth as well as enzyme activity rather than the induction method at low cell density or the constitutive expression.

• 분석과학
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• 제12권3호
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• pp.196-202
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• 1999

갈조류인 Sargassum horneri를 중금속 흡착제로 사용하여 중금속 Cd(II) 및 Pb(II)이온을 제거하였다. Sargassum horneri는 동해안에서 채취하였고, 풍건 건조시켜 40~60 mesh의 입자 크기로 흡착제를 만들어 사용하였다. batch법은 진탕 시간에 따른 흡착량을 측정함으로써 흡착속도를 조사하였고, column법은 해조 분말을 충진 시킨후 일정농도의 중금속용액을 1 mL/min의 속도로 흘려보내면서 흡착시키고 흡착량을 알아 보았다. 중금석 흡착에 미치는 pH의 영향은 batch법과 column법 모두, pH 10.5>7.0>3.5순으로 나타났다. Pb(II)이온이 Cd(II)이온보다 높은 흡착량을 보였다. 특히 batch법에서는 모든 pH의 조건하에서 5분이내에 최대 흡착량에 도달하였다. 회수율은 batch법에 의해 흡착된 중금속의 회수율이 column법에 의해 흡착된 중금속의 회수율 보다 조금 높게 나타났다.

• 산업경영시스템학회지
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• 제43권4호
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• pp.23-32
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• 2020

Many small and medium-sized manufacturing companies process various product types to respond different customer orders in a single production line. To improve their productivity, they often apply batch processing while considering various product types, constraints on batch sizes and setups, and due date of each order. This study introduces a batch scheduling heuristic for a production line with multiple product types and different due dates of each order. As the process times vary due to the different batch sizes and product types, a recursive equation is developed based on a flow line model to obtain the upper bound on the completion times with less computational complexity than full computation. The batch scheduling algorithm combines and schedules the orders with same product types into a batch to improve productivity, but within the constraints to match the due dates of the orders. The algorithm incorporates simple and intuitive principles for the purpose of being applied to small and medium companies. To test the algorithm, two case studies are introduced; a high pressure coolant (HPC) manufacturing line and a press process at a plate-type heat exchanger manufacturer. From the case studies, the developed algorithm provides significant improvements in setup frequency and thus convenience of workers and productivity, without violating due dates of each order.