• 멤브레인
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• 제32권5호
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• pp.348-356
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• 2022

바이오산업의 발전으로 의약품, 식품 등의 생산 과정의 분리/정제 공정에 사용되어 왔던 기존의 컬럼 크로마토그래피를 대체하여 더 높은 처리효율을 갖는 막 크로마토그래피가 부상하고 있다. 본 연구에서는 서로 다른 기공 크기의 두 가지 상용 셀룰로오스 아세테이트(Cellulose acetate, CA) 분리막을 탈아세틸화 과정을 통해, 리간드의 개질이 용이한 다공성 재생 셀룰로오스 지지체를(Regenerated cellulose, RC) 제조하였다. 음이온 교환능을 부여하고자 grafting을 수행하였으며, 구체적으로는 UV 중합법을 통해 4차 암모늄을 포함하는 음이온 교환 리간드(MAPTAC)를 부착하여 음이온 교환용 흡착막을 제조하였다. 단백질 흡착 용량은 정적 흡착 용량(Static binding capacity, SBC)시험을 통해 총 단백질 흡착 용량을 측정했고, 동적 흡착 용량(Dynamic binding capacity, DBC)을 측정하여 상용막과 비교 평가하였다. 성능 평가 결과 단백질 흡착량은 넓은 표면적에 의해 리간드 밀도가 높은, 기공 크기가 작은 순서로 높게 측정되었고, 상용 CA분리막을 탈아세틸화하고 리간드를 부착시킨 분리막(RC 0.8 + MAPTAC 43.69 mg/ml, RC 3.0 + MAPTAC 36.33 mg/ml)이 상용 막 크로마토그래피 제품(28.38 mg/ml) 대비 높은 흡착 용량을 보였다.

• 멤브레인
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• 제27권5호
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• pp.406-414
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• 2017

본 연구에서는 얇은 폴리에틸렌 계 다공성 필름(두께 = $25{\mu}m$)에 이오노머를 충진시킨 세공충진 이온교환막을 개발하였으며 이를 적용한 전 바나듐 레독스 흐름전지의 충방전 특성을 고찰하였다. 특히 분자 크기가 다른 가교제를 혼합함으로써 이온교환막의 가교도 및 자유체적을 적절히 제어하여 저저항 및 저 바나듐 투과도를 나타내는 이온교환막을 제조하고자 하였다. 실험 결과, 제조된 세공충진 이온교환막은 상용막 대비하여 동등 수준의 우수한 전기화학적 특성을 나타내었다. 또한 바나듐 이온 투과도 및 전 바나듐 레독스 흐름전지 성능 평가 실험을 통해 얇은 막 두께에도 불구하고 상용막 대비하여 낮은 바나듐 이온 투과도와 높은 충방전 효율을 나타냄을 확인하였다.

• 멤브레인
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• 제24권4호
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• pp.332-339
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• 2014

본 연구에서는 축전식 탈이온 공정(capacitive deionization, CDI)의 성능을 개선하기 위해 poly(2,6-dimethyl-1,4-phenylene oxide) (PPO)를 기저물질로 이용하여 코팅이 가능한 음이온교환 이오노머(quaternized PPO, QPPO) 용액을 제조하였다. 제조된 QPPO는 상용 음이온교환막(AMX, Astom Corp., Japan) 대비 우수한 이온전도도 특성을 나타내었으며 전기화학적 특성 또한 동등 수준임을 확인할 수 있었다. 다공성 탄소 전극에 이오노머 용액을 코팅하여 CDI 성능평가를 수행하였으며 그 결과 약 94.9%의 높은 염 제거 효율을 나타내었다. 기존의 CDI와 상용 음이온교환막을 결합한 membrane CDI (MCDI), QPPO가 코팅된 전극을 사용한 coated CDI (CCDI)의 탈염 성능을 비교한 결과 QPPO의 높은 이온선택성 및 낮은 이온 전달저항으로 CCDI가 기존의 CDI에 비해 52.1%, MCDI에 비해 18.3% 향상된 높은 염 제거 성능을 나타냄을 확인하였다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2002년도 춘계종합학술대회
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• pp.456-460
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• 2002

오늘날 비즈니스의 가장 큰 변화의 원인은 인터넷을 통한 전자상거래이다. 최근 이러한 인터넷을 통한 전자상거래는 기업간(B2B) 거래에 가장 큰 영향을 주고 있다. 인터넷을 통한 기업간 거래에 필요한 정보 교환 문서는 효율적으로 정보를 전송하고 시스템에 독립성을 가지며 거래 파트너간 상호 운용성을 향상 시켜야 한다. 기존의 정보 교환 전자 문서는 e-business에서 사용함에 있어서 정보교환 및 상호운용성 측면에서 문제점들이 발생하였다. 때문에 XML의 등장은 기존의 정보 교환 전자문서들이 가지고 있었던 문제점들을 해결할 수 있는 계기가 되었다. 또한, XML을 기반으로 하는 전자 상거래가 구축되었다. 이렇듯 e-business에 필요한 문서를 작성함에 있어서 XML 문서뿐만 아니라 XML 문서의 구조를 정의한 DTD나 XML Schema의 생성이나 편집 또한 필요하게 되었다. 이에 본 논문에서는 XML을 기반으로 한 e-business 문서 생성 및 편집을 위한 XML 편집기, DTD 편집기, XML Schema편집기 등의 통합 문서 편집 시스템을 설계 및 구현하였다.

• 영어영문학
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• 제55권5호
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• pp.767-792
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• 2009

The two fields, economics of art and literature, tend to be put together as part of cultural economic studies; yet the former has been widely popular as compared to the latter. Economics of art has been known as part of social science which studies art economically. Similarly, economics of literature is likely to be an interdisciplinary study of literature and economics. Literature is suggested usually to reflect the economic base of a society as a form of its superstructure in view of classical Marxism; so, it is interesting to see social, economic activities, such as individual values and social institutions, income, price and opportunity cost, in a particular way of analyzing economic ideas in literature. Capital seems to have an innate property of self-expansion in literature; this property thus features actual economic life since in capitalism money is the universal value between persons and literary works. Specifically, the field of economics of literature starts with such ideas: economics of literature is part of cultural economics; and economics of literature deals with the economic value of literature. Putting interdisciplinary fields of literature and economics together, this study is to examine the economic value of literature in which Karl Marx talked about commodities with exchange value, use value, and fetishism. The exchange value is commercial worth, the actual exchange value of a publication; yet, the use value is innate worth, the aesthetic use value of literature. With commodity fetishism, profit seems not as the outcome of a social relation, but of a work- "reification" as the would-be Marxists suggest. As a commodity, the literary work appears to be able to animate life and power in reality. As a result, this paper asserts that social, economical activities in literature as we may apply to the study of economics of literature increase its economic value, implying commercial and innate worth, as the capital in the marketplace.

• Journal of Microbiology and Biotechnology
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• 제30권8호
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• pp.1180-1183
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• 2020

The prevalence and characterization of plasmid-mediated quinolone resistance (PMQR) determinants in ciprofloxacin-resistant Escherichia coli isolated from a Korean commercial layer farm were studied. A total of 45 ciprofloxacin-resistant E. coli isolates were recovered and all isolates were multidrug-resistant. Eight isolates have the PMQR genes aac(6')-Ib-cr, qnrS1, and qnrB4, and seven isolates exhibited double amino acid exchange at both gyrA and parC, and have high fluoroquinolone minimum inhibitory concentrations. Five transconjugants demonstrated transferability of PMQR and β-lactamase genes and similar antimicrobial resistance. Because PMQR genes in isolates from commercial layer chickens could enter the food supply and directly affect humans, control of ciprofloxacin resistance is needed.

• 통상정보연구
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• 제8권3호
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• pp.259-275
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• 2006

The purpose of this study is to analyze trade environment and examine a commercial practices for a successful launching of Indian market In general, Indian trade environment is composed of a natural environment, religious peculiarity, history and politic and economic prospect. In order to understand Indian commercial practices and secure business achievements, its national character, mode of living, customs related to foods and social relations such as exchange of gifts, religious taboos, tendency of product preference should be recognized. The results of the study indicate mostly that even though an excellent brand image, a good quality and an efficient sales network are a basic factor for making of a successful business, practically it is more important to understand a business customs and national character of indian people. Because business is accomplished through relationship between human beings eventually.

• 한국정밀공학회지
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• 제23권12호
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• pp.95-102
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• 2006

A product is designed through the collaboration among engineers in several fields such as design, analysis, and manufacturing. These series of functions are performed repeatedly during the design process. An easy access and exchange of the model data is one of the important elements that help to shorten production development time. Especially, the importance of data exchange between CAD and CAE applications is increasing in the field of verification and estimation of the products. However, information and knowledge of model which is generated by a CAD software cannot be transferred by a function of CAE software, as an exchange of product data between CAD and CAE applications. It causes a delay in design analysis and eventually discourages a designer's effort in improving his design. Therefore, we need to integrate a commercial CAD and CAE applications effectively and to use the same interface on a product model obtained in a distributed environment. This paper shows how to implement a model exchange between CAD and CAE by a web-service and how to provide a communication environment among engineers.

• 한국수소및신에너지학회논문집
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• 제22권2호
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• pp.184-190
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• 2011

The membrane properties (membrane resistance and ion exchange capacity) of the five types of commercial anion exchange membrane, i.e. IOMAC, AHT, APS, AHA, AFN, were evaluated for the application in the alkaline electrolysis. The membrane resistance decreased in the order; in 1M KOH: AHT>IOMAC>AHA>AFN>APS; in 1M NaOH: AHT>IOMAC>AHA>APS>AFN. The ion exchange capacity decreased in the order: AFN>APS>AHT>AHA>IOMAC. The membrane life was determined from the change of membrane resistance in 1M KOH and NaOH with an increase of soaking time in 20 wt% KOH and 30 wt% NaOH solution. AHA membrane had a good membrane life in 20 wt% NaOH with its unchanged membrane resistance. And, AFN and AHA membrane had a good membrane life in 30 wt% NaOH with its unchanged membrane resistance.

• Journal of Ship and Ocean Technology
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• 제9권3호
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• pp.23-32
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• 2005

Ship STEP(Standard for the Exchange of Product Model Data) which is composed of AP 215 (Ship Arrangement), AP 216(Ship Hull Form), AP 218 (Ship Structure), has been developed more than last 10 years and it is now at the stage just before IS(International Standard). It is expected that ship STEP would be used for the seamless data exchange among various CAD/CAM/CAE systems of shipbuilding process. In this paper the huge and complicated data structure of ship STEP is briefly reviewed at the level of ARM(Application Reference Model) and some abstract test cases which will be included as part of the standards are introduced. Basically ship STEP has common data model to be used without losing compatibility among those three different ship AP's, and it is defined as the modeling framework. Typical cases of data exchange during shipbuilding process, such as hull form data exchange between design office and model basin, midship structure data between shipbuilding yard and classification society are reviewed and STEP physical data are generated using commercial geometric modeling kernel. Test cases of ship arrangement at initial design stage and hydrodynamic data of crude oil carrier are also included.