• KSBB Journal
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• 제5권3호
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• pp.223-227
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• 1990

Ethanol을 주로 생산하는 균주인 Z. mobilis의 cell wall 투과성을 높인 후 고정화하여 sorbitol 생산에 이용 하였다. 그러나, toluene으로 투과성을 높은 cell은 oxidoreductase의 유출, 손실로 인하여 sorbitol conversion efficency가 급격히 저하되었다. 따라서, 이와같은 enzymcd의 유출을 방지 하기 위하여, 투과성을 향상시킨 cell을 0.25% glutaraldehyd로 처리한 후 alginate와 chitin에 고정화하여 회석율 $0.2h^{-1}$에서 연속배양을 한 결과 210시간동안 효소활성도의 저하는 거의 일어나지 않았다. 이와같은 연속배양에서 얻어진 sorbitol productivity는 3.5g / l-h로 측정 되었다.

• 한국표면공학회지
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• 제38권6호
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• pp.212-215
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• 2005

Novel continuous electroforming process equipped with a rotating patterned mandrel, soluble/insoluble anode and multiple stage of rolling wheels was proposed to produce precision nickel mesh, which is known as a very efficient electromagnetic interference (EMI) shielding material. Continuously electroformed nickel deposits showed a tendency to form small-sized particles as the plating solution temperature increased and mandrel rotation speeded up and the applied current density decreased. Along the honeycomb patterns of mandrel, nickel was accurately electrodeposited on the surface of rotating mandrel, but quite different visual/structural characteristics were measured on both sides.

• 산경연구논집
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• 제6권3호
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• pp.5-8
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• 2015

Purpose - This article's aim is to examine how the utilization of existing and future decision-support systems will lead to a change in the auditing process. Research design, data, and methodology - An information system is a special decision-support system that combines information obtained from various sources and communicates among them to help in assessing appropriate complex financial decisions. This paper analyzes techniques such as data and text mining as components of decision-support systems to be used in the auditing process. Results - We present views about how existing decision-support systems will lead to a change in audits. Auditors, who currently collect significant data manually, will in the future move towards management through complex decision-support systems. Conclusions - Although some internal audit functions are integrated into systems of continuous monitoring, the use of such systems remains limited. Thus, instead of multiple decision-support systems, a unified decision-support system can be deployed for this that includes sensors integrated within a company in different contexts (e.g., production, sales, and accounting) that continually monitors violations of controls, unusual patterns, and unusual transactions.

• 품질경영학회지
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• 제20권2호
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• pp.55-66
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• 1992

The sampling plan CSP-1 for continuous production was first proposed by Dodge in 1943. Continuous production refers to products which are flowing past the inspection station such as products moving on a conveyor belt. One important measure of the effectiveness of a CSP is the average outgoing quality(AOQ). A concept for a short run of production length time, denoted by AOQ(t), is provided. The assumption of a s-independence in CSP-1 is unrealistic. It is possible to relax the assumption of a s-independence. The need for Markov model in a continuous production process can be discussed in this paper. The Markov and renewal theory are used to describe the property of AOQ in CSP-1.

• 대한기계학회논문집B
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• 제23권7호
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• pp.820-830
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• 1999

The coupled turbulent flow and solidification is considered in a typical slab continuous easting process using commercial program FIDAP. Standard $k-{\varepsilon}$ turbulence model is modified to decay turbulent viscosity in the mushy zone and laminar viscosity is set to a sufficiently large value at the solid region. This coupled turbulent flow and solidification model also contains thermal contact resistance due to the mold powder and air gap between the strand and mold using an effective thermal conductivity. From the computed flow pattern, the trajectory of inclusion particles was calculated. The comparison between the predicted and experimental solidified shell thickness shows a good agreement.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 춘계학술대회 논문집
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• pp.134-137
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• 2005

In this paper, a continuous contact treatment has been considered during FE-analysis of the sheet metal forming processes. Because the simulation is usually performed stepwise, the status of contact can change suddenly. In case of implicit scheme, the increment of punch stroke can be chosen as large value. For exact assessment of contact force and friction force between die and sheet, the continuous contact treatment is proposed. The virtual surface of sheet metal is modeled by NURBS curves or surfaces in order to calculate exact contact area and penetration depth. From the geometrical evaluation of contact behavior, additional contact pressure is imposed to the element. The deformation of bending process and hydroforming process are analyzed based on this scheme.

• 한국기계가공학회지
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• 제18권5호
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• pp.53-59
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• 2019

Continuous ship unloaders (CSUs) are used for the uninterrupted transport of material in processing industries, power plants, and harbors in accordance with the stream rate of the material. This study analyzed the structural integrity and fatigue life of a CSU structure using finite element structural analysis in ANSYS APDL software. The stress varied greatly depending on the luffing angle and the slew angle of the boom conveyor. The structural integrity of the CSU girder was evaluated by applying ASME BPVC Section VIII Division 2. The fatigue cycle at the angle with the greatest stress difference was calculated. The fatigue cycle was calculated by applying the JIS B 8821:2013 fatigue curve. It was confirmed that the fatigue cycle of the CSU satisfies the allowable fatigue of 200,000 cycles.

• Korean Chemical Engineering Research
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• 제43권4호
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• pp.467-473
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• 2005

액상의 아산화질소($N_2O$) 혼합물은 주요 불순물로써 공기, 일산화탄소, 수분, 이산화탄소와 NOx 성분을 포함하고 있다. 저온에서 고체화하여 고 순도의 $N_2O$를 얻어내는 것은 위험하다고 알려져 있다. 본 연구에서는 연속식 증류공정에 기초하여 고 순도의 $N_2O$ 제품을 얻어내는 새로운 방법을 소개하였다. 99.999％ 이상의 고 순도의 $N_2O$ 제품을 얻어낼 수 있는 연속식 증류공정을 모델화하기 위하여 intalox wire guaze 타입의 SCH-80S의 충진탑을 사용하였다. Peng-Robinson 상태방정식을 사용하여 연속식 증류탑과 냉동 사이클을 모사하였다. 본 연구에서 수행한 전산모사 결과는 상용성 화학공정모사기인 Aspen Plus로 모사한 결과와 매우 잘 일치함을 알 수 있었다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 춘계학술대회
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• pp.110-112
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• 2006

Membrane electrode assembly (MEA) for polymer electrolyte fuel cell (PEFC) are commonly prepared in the research laboratory by spraying, screen-printing and brushing catalyst slurry onto membrane or other support material like carbon paper or polyimide film in a batch style. These hand applications of the catalyst slurry are painstaking process with respect to precision of catalyst loading and reproducibility. It has been generally mentioned that the adoption of continuous process is very helpful to develop the reliable product. In the present work, we report the results of using continuous type coater with doctor-blade to coat catalyst slurry for preparing the MEA catalyst layers In a faster and highly reproducible fashion. We show that while expectedly faster than batch style, the machine coater requires the use of slurry of appropriate composition and a properly selected transfer decal material in order to achieve superior MEA plat lnw loading reproducibility. To make highly viscous catalyst slurry that is imperative for using coater, we use 40wt.% Nafion solution and minimize the content of organic solvent. And the choice of proper high surface area catalyst is important in the viewpoint of making well-dispersed slurry. After catalyst coating onto the support material, we transferred the catalyst layer to both sides of Nafion membrane by hot-pressing In this case, the degree of transfer was Influenced by hot-pressing condition including temperature, pressure, and time. To compare the transferring ability, we compared so many films and detaching papers. And among the support, polyethylene terephthalate(PET) film shows the prominent result.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제4권1호
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• pp.93-100
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• 2000

This paper deals with some fundamental matters pertaining to estimation of critical quantities associated with continuous processes which are frequently related to the quality rating of the product. Specifically, it examines bounds on estimation and bounds on the estimation error variance. It draws on recent results from the theory of mathematical inequalities and their applications.