• 상하수도학회지
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• 제22권3호
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• pp.289-298
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• 2008

Because of their simplicity, efficiency, and economy, slow sand filters are appropriate means of water treatment for small water systems. Biological activity within the sand bed have the strongest influence on removal efficiency of pollutants by slow sand filtration. This report investigated the microorganisms(algae) of slow sand filtration pilot plant at Y water treatment plant. Data were collected at inflow and slow sand filtration from May to October, 2007. The results indicated that the light exposure was influenced on microorganism in slow sand filtration according to the formation of algal biofilm. The relative contribution of biomass and accumulated particulates to head loss development in slow sand filters requires further study.

• 한국의류학회지
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• 제35권11호
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• pp.1386-1398
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• 2011

Slow fashion can be viewed as an activism that provides an alternative solution to the problematic issues of fast fashion in a practical sense; however, (from a theoretical point of view) it is a fashion phenomenon arising from the criticism of an accelerating society. Slowness emphasizes the virtues of moderation. Slowness refers to the recovery of human ethics that have been neglected due to the goal-oriented nature of an accelerating society. Slowness can solve the problem of conformity and discrimination in society through pluralism and respect for local indigenousness. The characteristics of slow fashion can be defined by the aesthetic values of circularity, sustainability, moderation, expressivity and convergence. This includes the beauty of circularity (which views the relationships of all processes as organic), the beauty of sustainability (which ensures the maintenance of continuous emotions and the durability of products that can be promoted through slow processes), the beauty of moderation (which places importance on spiritual values and the moderate use of materials), and the beauty of expressivity (which plays the role of a social messenger that facilitates social assertion). These combined values present the beauty of convergence such as the harmony of local communities and the world in a blend of the old and the new with an exchange between producers and consumers.

• 대한전자공학회논문지
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• 제27권12호
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• pp.1859-1864
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• 1990

The effect of H+ and OH- ion concentrations at doped Si semiconductor/pH buffer solution interfaces were investigated in terms of cyclic current-voltage characteristics. The effects of space charge on oppositely doped Si semiconductors, i.e., p-and n-Si semiconductors, can be effectively applied to study the pH effects and the slow surface states at the interfaces. The adsorptions of H+ and OH- inons on the doped Si semiconductor surfaces are physical adsorption rather than chemical adsorption. Adsorptive processes and charging effects of the slow surface states can be explained as the potential barrier variations and the related current-voltage characteristics at the interfaces. Under forward bias, the charged slow surface states on the p-and n-si semiconductor surface are donor and acceptor slow surface states, respectively. The effects of minority carriers on the slow surface states can be neglected at the doped Si semiconductor interfaces.

• 상하수도학회지
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• 제22권4호
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• pp.461-466
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• 2008

Because of their simplicity, efficiency, and economy, slow sand filters are appropriate means of water treatment for small water systems. In this study, the effect of filtration velocity and dirty skin (Schmutzdecke) was evaluated on the performance of turbidity removal. Also, removal characteristics of particulate were investigated in the case of the usage of non-woven fabric on the surface of sand and the application of PCF as pretreatment process. Comparative column tests were carried out for the various operation condition. From the result of column tests, filtration velocity had little effect on the turbidity removal rate. The formation of algal biofilm on the surface of media is helpful in turbidity removal, while non-woven fabric is not as effective as expected. The relative contribution of biomass and accumulated particulates to head loss development in slow sand filters requires further study.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2000년도 제20회 KOSCO SYMPOSIUM 논문집
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• pp.133-141
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• 2000

The present study is focused on modeling the transient behavior of the local flame structure which is especially important for slow reaction processes, such as NOx formation in the radiating flame field. The recently developed unsteady flamelet model has been applied to analyze a steady, turbulent jet flame. Numerical results are compared with experimental data and numerical results of the conventional steady flamelet model. The numerical result reveals that the unsteady flamelet model correctly predicts the nonequilibrium effect upsteam and the subsequent decay of the superequilibrium radical concentrations the further downstream.

• 한국분무공학회지
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• 제6권3호
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• pp.8-16
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• 2001

The present study is focused on modeling the transient behavior of the local flame structure which is especially important for slow reaction processes, such as NOx formation in the radiating flame field. The unsteady flamelet model recently developed has been applied to analyze a steady, turbulent jet flame. Numerical results are compared with experimental data and numerical results of the conventional steady flamelet model. The numerical result reveals that the unsteady flamelet model correctly predicts the nonequilibrium effect upsteam and the subsequent decay of the superequilibrium radical concentrations further downstream.

• 대한안전경영과학회지
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• 제9권3호
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• pp.95-102
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• 2007

Nowadays, globally high-grade companies have done their best for increasing their competitive power through a many kinds of method in incisive competition for making certain of a pacesetting position. Among the rest, Six Sigma have been the best methodology of improving process and have proven to be effective by the result of improving process in many of manufacturing business, however, it has not obtained excellent results in the transaction business. In transaction business, a $30\sim50%$ costs in total costs is generated by slow-speed working and reworking. The slow processes decrease the quality and increase the cost, which decreases customer satisfaction, and finally the income is decreased. All of them are so called wastes in processes. For this, adopting of lean six sigma methodology in process management can eliminate the wastes and reduce the variation. This study focuses on distribution with the domains like capacity, layout, amount of location, assignment of product, operation procedure and operation rule in order to improve these domains, we make a further application of eight analysis ways based on DMAIC method for improving operation of processes of distribution center as the third profit source. The goal of this study is to trace an approach that can easily adopt of Lean Six Sigma in operational management of distribution center by a kind of data, analysis method and template.

• 정보처리학회논문지A
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• 제10A권4호
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• pp.313-320
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• 2003

본 논문에서는 분산 환경에서 e-비즈니스 프로세스들 간에 SFT(Slow Frequency Transaction) 데이터를 처리하는 동기화 에이전트 시스템을 설계 및 구현한다. 이 동기화 에이전트 시스템은 분산 프로세스들의 상호운용성 보장과 클라이언트/서버 구조의 문제를 해결하기 위해 이동에이전트를 이용하며, 분산된 이종 시스템 플랫폼상의 e-비즈니스 프로세스들의 데이터 동기화를 위한 정책을 제시한다. 제안된 동기화 정책은 유니캐스팅 전송 상에서 시스템 우선순위와 타임스탬프의 트랜잭션을 기본으로 한다.

• 상하수도학회지
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• 제19권2호
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• pp.209-213
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• 2005

Slow sand filtration processes amended with 5 and 10cm GAC layers at top was compared to same process at bottom in a pilot study for humic substances removal. In case of 5cm GAC layer, the process amended at bottom was superior to the process at top in DOC and UV254nm removal and same trends were observed in case of 10cm GAC layer. Head loss developments of the process GAC at bottom were higher than the process GAC at top so that maintenance of the process GAC at top is easier than the process GAC at bottom.

• 한국농공학회지
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• 제28권1호
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• pp.41-50
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• 1986

This paper attempts to qualitatively characterize scour erosion processes near USGS constriction type-I structures with vertical embankments and abutments. The scour dimensions and rates of sand beds around the structure models were measured in a rectangular flume. The test results showed that scour took place at a rapid rate at initial stages, which were followed by a stage of slow and general scour with greater extends. The maximum scour depth was observed near upstream corner of embankments. Empirical relationships for scour dimensions were derived, that were based on the results from a dimensional analysis of scour processes.