• 경영과학
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• 제31권3호
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• pp.27-39
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• 2014

We derive a generalized statistic form of Q control chart, which is especially suitable for short run productions and start-up processes, for the detection of process mean shifts. The generalization means that the derived control chart statistic concurrently uses within lot variability and between lot variability to explain the process variability. The latter variability source is noticeably prevalent in lot type production processes including semiconductor wafer fabrications. We first obtain the generalized Q control chart statistic when both the process mean and process variance are unknown, which represents the case of implementing statistical process control charting for short run productions and start-up processes. Also, we provide the corresponding generalized Q control chart statistics for the rest of three cases of previous Q control chart statistics : (1) both the process mean and process variance are known (2) only the process mean is unknown and (3) only the process variance is unknown.

• 융복합기술연구소 논문집
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• 제1권1호
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• pp.13-17
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• 2011

The car industry is one of the technological applications which more rare earth metals employes as three-way catalysts. Therefore, the recovery of rare earth metals from the used automotive three-way catalysts could be important source to obtain these metals. This work presents the analysis of market and demand for rare earth metal in automotive three-way catalyst and introduces the dry and the wet processes for the recovery of rare earth metals from used three-way catalyst. Finally, the alternative methods to conventional wet processes was simply suggested based on the economic and ecological point of view.

• 대한기계학회논문집
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• 제17권1호
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• pp.172-181
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• 1993

본 연구에서는 이 사이클 주위에 열전달이 추가된 열기관에 대하여 최대출력 조건 등을 구하고, 내부의 사이클이 각각 타노 사이클 및 브레이튼 사이클인 경우의 결과와 비교하여, 내적가역 최대출력 사이클들의 특성을 밝히고자 한다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1197-1199
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• 2009

Self-alignment for the fabrication of printed thin film transistors has become of great interest because of the resolution and registration limits of printing technologies. In this work, self-patterning and selfregistration processes are introduced, which do not need surface energy patterning and the resulting minimum gate channel length could be down to $11.2{\mu}m$ with the sheet resistance of 2.6 ${\Omega}/{\square]$ for the source and drain electrodes.

• 한국정보과학회논문지:소프트웨어및응용
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• 제35권7호
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• pp.417-423
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• 2008

본 논문에서는 각 음원이 시간적 구조를 가졌을 경우 음원들을 분리해내는 확률적 음원분리 방법을 제안한다. 이를 위해 각 음원의 시간적 구조를 가우시안 프로세스(Gaussian process)로 모델링하고 기존의 음원분리 문제를 유사-가능도 최대화 문제(pseudo-likelihood maximization)로 공식화한다. 본 알고리즘을 통해 얻어진 데이타의 유사-가능도는 정규 분포이며 이는 가우시안 프로세스 회귀방법(Gaussian process regression)을 통해 쉽게 계산이 가능하다. 음원분리의 역혼합 행렬은 경도(gradient) 기반최적화 기법을 통해 데이타의 유사-가능도를 최대화하는 해를 찾음으로써 구해진다. 여러 실험을 통하여 제안 알고리듬이 몇 가지 특정 상황에서 기존의 분리 알고리듬들에 비해 우수한 성능을 보임을 확인 할 수 있다.

• 상하수도학회지
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• 제14권3호
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• pp.224-230
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• 2000

Membrane processes are capable of removing much materials from water. The removal or rejection characteristics of a membrane is usually depend upon the nominal pore size or MWCO(molecular weight cut off). A membrane with a smaller nominal pore size or MWCO should be capable of removing smaller contaminants from water. A series of experiments was performed to investigate the separation characteristics of membrane processes which consisted of microfiltration(MF) and nanofiltration(NF). To evaluate removal efficiencies of some pollutants such as the consumption of $KMnO_4$, THMFP, NH3-N, Fe, Mn, and pesticides, source water sampled from the Kum river was treated by the those membrane processes. Also, the results of experiments were compared with those of conventional water treatment processes. By two types of the membrane process, total removal efficiency of $KMnO_4$ consumed, THMEP, and $NH_3-N$ were 91.0%, 84.3%, and 85.5%, respectively and those processes were efficient in pesticides removal as well. Most of the effluents satisfied the Korean standard of drinking water quality continuously in the experimental periods. However, NF was needed for producing the safe drinking water in case of treating the raw water contaminated with Mn since removal efficiency of MF was not high enough. On the basis of the experimental results, it was suggested that NF could be applied to remove not only $NH_3-N$ but THMFP even without pre-chlorination.

• 한국정보시스템학회지:정보시스템연구
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• 제31권1호
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• pp.25-58
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• 2022

Purpose The purpose of this study is to analyzes the RPA fitting processes by the casese of manufacturing SMEs(Small and Medium-sized Enterprises) in an exploraty approach. Based on the findings on the RPA fitting processes, we intend to provide a cornerstone for developing a general-purpose RPA introduction model in the future. Design/methodology/approach In this study, empirical cases of RPA fitting processes were analyzed based on interviews with project managers of specialized IT suppliers in charge of RPA development and managers of IT departments of manufacturing SMEs that actually introduced RPA. In order to explore various RPA fitting process in the manufacturing value chain, a total of 7 manufacturing SMEs were interviewed, ranging from companies using a legacy system to companies without a legacy system. Over the primary and secondary activity processes, the details of RPA processes were analyzed in the steps of 'Frequency Identification, Input Processing, Source Identification, Inquiry and Processing, Information Registration, Result Reporting'. Findings From the analysis, we derived some exploratory results that the processes over 0.25 FTE and related with many suppliers and clients are fitting for RPA introduction in manufacturing SMEs Our results will provide basic data for the development of the future general-purpose RPA introduction model for manufacturing SMEs, providing practical reference for RPA introduction.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2012년도 춘계학술발표회 논문집
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• pp.128-128
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• 2012

Korea institute of materials science (KIMS) has researched an anode layer linear ion source (ALIS) for various roll-to-roll treatment processes. The ALIS can be used to Ar ion beam (1~2 keV) treatment, and diamond-like carbon coating and so on. The treatment width of ALIS is 500 mm with a uniformity below 5 % (=(Max-min)/(Max+min)). We also demonstrate the status of development of ALIS in a roll-to-roll industry.

• 상하수도학회지
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• 제29권1호
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• pp.1-9
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• 2015

A combined treatment system using multiple source water is becoming important as an alternative to conventional water supply for small-scale water systems. In this research, combined water treatment systems were investigated for simultaneous use of multi-source water including rainwater, ground water, river water, and reclaimed wastewater. A laboratory-scale system was developed to systematically compare various combinations of water treatment processes, including sand filtration, microfiltration (MF), granular activated carbon (GAC), and nanofiltration (NF). Results showed that the efficiency of combined water treatment systems was affected by the quality of feed waters. In addition, a simply approach based on the concept of linear combination was suggested to support a decision-making for the optimum water treatment systems with the consideration of final water quality.

• 한국환경과학회지
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• 제8권1호
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• pp.135-144
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• 1999

Air quality modeling about coastal urban region such as Pusan shoud be consider shipping source emmited from ships anchoraging and running. It has been proved at our previous studies that the ratios of air pollutants emission amount in coastal area to inland are 12.2% for NO$_2$ and 11.7% for $SO_2$ and the air qualify of coastal urban area consierably counts on ships. Also the dispersion pattern of the all pollutants followed local circulation system in this region. Therefore this study has been developed air quality model which can describe the formation, transport, transformation and deposition processes of air pollutants considering shipping source. Currently, restriction for emission amount of ships does not exist, so our study will be useful to set the omission standard and for devising air quality policy in coastal urban region.