• 한국산업정보학회논문지
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• 제12권4호
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• pp.107-118
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• 2007

A single-server queueing model with infinite buffer and batch arrival of customers is considered. In contrast to the standard batch arrival when a whole batch arrives into the system at one epoch, we assume that the customers of an accepted batch arrive one-by one in exponentially distributed times. Service time is exponentially distributed. Flow of batches is the stationary Poisson arrival process. Batch size distribution is geometric. The number of batches, which can be admitted into the system simultaneously, is subject of control. Analysis of the joint distribution of the number batches and customers in the system and sojourn time distribution is implemented by means of the matrix technique and method of catastrophes. Effect of control on the main performance measures of the system is demonstrated numerically.

• 한국환경보건학회지
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• 제30권2호
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• pp.84-91
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• 2004

Biological nutrient removal(BNR) from wastewater was performed by adopting various process configurations. The simultaneous biological organics, phosphorus and nitrogen removal of synthetic wastewater was investigated in a sequencing batch biofilm reactor (SBBR). The other reactor was operating as a reference, without biofilm being added. The cycling time in SBR and SBBR was adjusted at 12 hours and then certainly included anaerobic and aerobic conditions. Both systems has been operated with a stable total organic carbon(TOC), nitrogen and phosphorus removal performance for over 90 days. Average removal efficiencies of TOC and total nitrogen were 83% and 95%, respectively. The nitrification rate in SBR was higher than that in SBBR. On the contrary, the denitrification rate in SBBR was higher than that in SBR. The phosphorus release was occurred in SBBR, however, not in SBR because of the inhibition effect of NO$_3$$^{[-10]}$ .

• 제어로봇시스템학회논문지
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• 제22권12호
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• pp.1040-1045
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• 2016

An inventory control system was developed for multiproduct batch plants with an arbitrary number of batch processes and storage units. Customer orders are received by the plant at intervals and in quantities that are subject to random fluctuations. The objective of the plant operation is to minimize the total cost while maintaining inventory levels within the storage or warehouse capacity by adjusting the startup times, the quantities of raw material orders, and production batch sizes. An adaptive model-based control algorithm was developed that uses a periodic square wave model to represent the flows of material between the processes and the storage units. The effectiveness of this approach was demonstrated by performing simulations.

• 산업경영시스템학회지
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• 제31권4호
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• pp.21-28
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• 2008

본 연구는 반도체 제조공정에서 사용되는 단일 Burn-In oven에서의 Total weighted earliness와 Tardiness를 최소화하기 위한 생산 스케줄링을 결정하는 문제를 다룬다. 본 연구에서는 모든 작업은 상시에 시작가능하고 각각은 서로 다른 가중치를 가지고 있다고 가정하였다. 일반적으로 단일 Burn-In oven은 다양한 작업들이 동시에 가능한 Batch processing 기계이다. 따라서 다양한 작업들로 구성된 하나의 Batch의 Processing time은 그 Batch 내에 있는 가장 긴 Processing time을 가지는 작업에 의해 결정된다. 본 연구에서 Batch size는 미리 결정되지 않은 상황이라고 가정한 후, 최적의 Batch 개수와 작업의 순서를 결정하기 위해 유전자 알고리즘을 적용하였다. 수리적 예제를 통해서 다양한 접근방법의 성능들을 비교한 결과, 유전자 알고리즘이 Total weighted earliness와 Tardiness를 최소화하는데 가장 뛰어난 성능을 가지고 있음을 알 수 있다.

• 한국초전도ㆍ저온공학회논문지
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• 제7권3호
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• pp.9-12
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• 2005

[ $Y_1Ba_2Cu_3O_{7-8}$ ] (YBCO) coated conductor has been fabricated by batch-type process using oxide-precursor-based metal-organic deposition (MOD) method. The batch-type process can be scaled up more simply to Produce long-length YBCO conductor than the reel-to-reel process. Also, it has less handling problems and is adequate to the ambient gas environment. In this work, YBCO oride powder was used as a starting precursor for MOD method. After reel-to-reel dip coating process, me ter-long-buffered metal tape was wound around a cylinder and underwent calcination and annealing processes. Annealed YBCO films showed good c-axis alignment and dense surface morphology with no cracks, but exhibited very low critical current density of $10^5\;A/cm^2$.

• 한국세라믹학회지
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• 제20권2호
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• pp.147-152
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• 1983

For $Na_2O-BaO-SiO_2$ system glass the pelletizing conditions of the disk type equipment were investigated. The effects of the pelletized batch on melting were also examined. Through the experiment the optimum conditions for pelletizing the batch were found as follows. Revolving speed of the pan 30rpm pan angle 40-35 degree Water content 12-13% Drying temperature $200^{\circ}C$ Preheating temperature $650^{\circ}C$ The molten glass of the pelletized batch was refined better than that of the loose batch.

• 한국초전도ㆍ저온공학회논문지
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• 제8권1호
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• pp.23-25
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• 2006

Optimization of process variables, including oxygen and water partial pressure and also an nesting temperature, was performed in batch-type process to fabricate YBCO films on LaAlO3 single crystal. In this work, YBCO oxide powder was used as a starting precursor for metal-organic deposition(MOD)method. The precursor films were fabricated in batch furnace and they were converted to the epitaxial YBCO films at the same furnace with varying the process variables. The oxygen partial pressure was varied from 100ppm to 2000ppm and the water partial pressure from 1.2% to 12.2%. The window for optimal P(O2) was narrow about 700ppm for batch-type process. YBCO films in bathc-thype MOD process were optimized at 740-770oC and P(H2O) of 2.3%-7.3%.

• Journal of Astronomy and Space Sciences
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• 제36권4호
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• pp.249-264
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• 2019

In this study, the precise orbit determination (POD) software is developed for optical observation. To improve the performance of the estimation algorithm, a nonlinear batch filter, based on the unscented transform (UT) that overcomes the disadvantages of the least-squares (LS) batch filter, is utilized. The LS and UT batch filter algorithms are verified through numerical simulation analysis using artificial optical measurements. We use the real optical observation data of a low Earth orbit (LEO) satellite, Cryosat-2, observed from optical wide-field patrol network (OWL-Net), to verify the performance of the POD software developed. The effects of light travel time, annual aberration, and diurnal aberration are considered as error models to correct OWL-Net data. As a result of POD, measurement residual and estimated state vector of the LS batch filter converge to the local minimum when the initial orbit error is large or the initial covariance matrix is smaller than the initial error level. However, UT batch filter converges to the global minimum, irrespective of the initial orbit error and the initial covariance matrix.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.390-393
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• 2001

The optimal temperature, pH and aeration rate for spore production by Bacillus polyfermenticus SCD in 500 ml shake flask and 5-1 jar fermenter were found to be $32^{\circ}C$, 7.0 and 1.0 vvm. respectively. When batch culture processes was performed under optimized culture conditions. viable cells were $3.3{\times}10^{10}$ CFU/ml and spore cells were $3.3{\times}10^{10}$ CFU/ml. Fed-batch culture processes were also examined with regard to higer maximum viable cell and spore production. The highe viable cells and spores were obtained in 5-1 jar fermenter at 72 h cultivation time by strategy in an intermediate feeding mode with 60% glucose solution 150 ml and 5% soybean flour solution 150 ml fed to the fermenter twice, and the productivity of spore cells was significantly increased. Finally. volumetric productivity of spore cells on fed-batch culture indicated $9.9{\times}10^8$ CFU/ml/h, which was approximately 2 times higher than batch culture. Thus, fed-batch culture show a promise as an industrial production method.

• 항공우주기술
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• 제2권2호
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• pp.45-49
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• 2003

한국항공우주연구원 위성시험동에 설치된 Bake-Out 챔버를 통하여 과학위성 1호 비행모델(STSAT-1FM)에 대한 Bake-Out 시험이 수행되었다. 본 시험은 시험 후에 장착될 FIMS라는 광학장비에 영향을 미칠 Outgassing Rate의 측정 및 고온에서의 Bake-Out을 통한 오염물질 제거에 목적을 둔 시험으로 총 10일여 동안 시험이 수행되었다. Honeycomb Panel 및 Harness에 대한 시험(Batch 1), 조립된 비행모델에 대한 Bake-Out(batch 2), 그리고 part별로 펼쳐진 상태로의 Bake-Out 시험(Batch 3), 총 세 번의 시험으로 이루어졌다. 각각의 시험에 대하여 TQCM(Thermoelectric Quartz Crystal Microbalance) 및 RGA(Residual Gas Analyzer)를 통하여 Outgassing 물질에 대한 정량적, 정성적 측정 및 분석이 이루어졌다.