• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2004년도 춘계 학술발표대회 개요집
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• pp.212-214
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• 2004

It is widely recognized that the residual stress of weldment affects steel construction and causes fracture initiation of welded structures. It is necessary to know since the power plants adopt a variety of welding processes distribution and magnitude of residual stresses. Therefore the purpose of present study is to investigate the validity of the indentation method to measure residual stresses of steel plates by residual stresses measured form the specimens of hot reheater pipes, cold reheater pipes and feed water lines used in power plants.

• 한국막학회:학술대회논문집
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• 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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• pp.25-28
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• 2004

In recent years, membranes have become fully or partially integrated into all facilities that produce drinking water since membrane processes can resolve technically complex and, at times, conflicting requirements related to compliance with multi-contaminant regulations. However, NF or RO technologies are hydraulically limited by the feed water quality that causes the fouling in a membrane system. In particular, NF or RO systems involved in surface water treatment generally require extensive pretreatment for controlling membrane fouling.(omitted)

• 한국생산제조학회지
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• 제23권4호
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• pp.325-329
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• 2014

This paper proposes a method to predict chatter vibration generated in milling processes and to enhance machining quality and surface finish. Chatter vibration is a common problem in the milling of thin walls and floors. It causes a poor surface finish, or even marks, to appear on the final machined surface. Therefore, an effective method is necessary to predict chatter vibration in machine tools. In this investigation, chatter vibration is measured by an accelerometer, microphone, and Acoustic Emission (AE) sensor in a machining operation. Based on the results of the experiment, a microphone can be applied for the prediction of chatter vibration in milling processes.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.725-731
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• 2009

Construction documents are recognized as an essential component for making a decision and supporting on construction processes. In construction, the management of project document is a complex process due to different factors such as document types, stakeholder involvement, document flow, and document flow processes. Therefore, inappropriate management of project documents can cause several impacts on construction work processes such as delay or poor quality of work. Several information and communication technologies (ICT) were proposed to overcome problems concerning document management practice in construction projects. However, the adoption of ICT may have some limitation on the compatibility of specific document workflow. Lack of understanding on designing document system may cause many problems during the use and implementation phase. Thus, this paper proposes the framework that integrates Soft System Methodology (SSM) concept and Integrated Definition Modeling Technique (IDEF) for analyzing document management system in construction project. Research methodology is classified as the case study. Five main construction building projects are selected as case studies. The qualitative data related to problems and processes are collected by interviewing construction project participants such as main contractors, owners, consultants, and designers. The findings from case study show the benefits of using SSM and IDEF. The use of SSM can help identify the problems in managing construction document in rich picture view whereas IDEF can illustrate the document flow in construction project in details. In addition, the idea of integrating these two concepts can be used to identify the root causes of process problems at the information level. As the results, this idea can be applied to analyze and design web-based document management system in the future.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2003년도 춘계학술대회 논문집
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• pp.121-122
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• 2003

Deposition to the sea surface is one of ozone's principal loss mechanisms (Galbally and Roy, 1980; Levy et al., 1985; Kramm, 1995). However, since complicated physical and chemical processes are involved, large uncertainties remain in evaluating this loss mechanism that need to be better characterized. In this study we attempted to explore possible causes that give rise to large variability of ozone deposition velocity in terms of wind speed and chemical reactivity in the aqueous-phase film. (omitted)

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 1992년도 자외선 차단 화장품의 SPF에 관한 심포지움(대한화장품학회)
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• pp.69-78
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• 1992

It is well hewn that ultraviolet light(UV) penetrates into the skin depends on the wavelength and causes many biochemical reactions in the skin. The enormous amount of information reveals that UV effects sun-burn, sun-tan and photoaging etc. In addition to these, it is now recognized that UV initiates immuno-suppression, and associated with this, skin cancer. In this review, I tried to illuminate the processes of injurious effects of UV on the skin.

• 한국지구과학회지
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• 제24권1호
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• pp.1-6
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• 2003

In this work, the present concentration levels of total gaseous mercury (TGM) are compared among three East Asian countries, Korea, China, and Japan. Comparison of Hg distribution patterns was made by selecting representative figures for each type of land use among those three countries. The results of the analysis indicate that Hg concentrations within a country can fall into a wide range due probably to the diversity of source processes. It is seen that the urban areas of China and Japan generally exhibit large spatial variability with notably high Hg levels (above 10 ng m$^{-3}$), compared to their Korean counterparts. Although the presence of high Hg levels in Chinese locations can be accounted for by the major man-made source processes (e.g., the use of coal), the causes of unexpectedly high Hg data in Japanese sites appear to be rather complicated. The Hg concentration levels in relatively remote locations however show much reduced values, above 3 ng m$^{-3}$, which is still higher than the typical background concentrations of 1 to 2 ng m$^{-3}$ in Europe or America. Considering that the presence of unusually high Hg levels in urban areas of Asia is the consequence of man-made activities, the prevalence of excessively high Hg values in certain regions of the Asian continent needs further research to accurately assess the fundamental picture of Hg geochemistry in the East Asia.

• 한국정보처리학회논문지
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• 제6권8호
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• pp.2158-2170
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• 1999

멀티캐스트 프로토콜을 이용한 분산 시스템들이 널리 사용됨에 따라 시스템의 성능 향상과 여러 프로세스에 대한 좀더 신뢰성 있는 통신이 요구되고 있다. 분산 환경에서는 프로세스들간의 비동기적인 수행으로 데이터의 일관성을 유지하는 문제와 여러 프로세스들의 활동을 조정하는 문제가 발생한다. 이러한 문제를 해결하기 위해 본 논문에서는 전체 순서화 알고리즘인 TORMP을 제안한다. TORMP는 멀티캐스트 프로토콜의 장점을 이용하여 효율적인 토큰 전달 방법을 사용한다. TORMP는 메시지 전송 요청을 한 모든 프로세스에게 동시에 토큰을 멀티캐스트 하여 각 프로세스의 메시지 전송 전 지연시간이 줄어든다. 또한 토큰을 받은 모든 프로세스들이 동시에 메시지를 멀티캐스트 하여 전체적으로 전송 지연도 크게 줄어든다. TORMP는 한 프로세스만 메시지를 전송하는 경우 순서화를 위한 제어과정이 거의 없다. TORMP는 벡터 클락을 이용하여 그룹내의 모든 프로세스에게 메시지 전송 권한을 공정하게 나누어준다. TORMP는 다른 알고리즘들과는 달리 순서화 과정동안 발생되는 패킷의 수가 프로세스의 수에 의존적이지 않다.

• IMMUNE NETWORK
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• 제13권5호
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• pp.213-217
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• 2013

Enterotoxigenic Bacteroides fragilis (ETBF) is a human gut commensal bacteria that causes inflammatory diarrhea and colitis. ETBF also promotes colorectal tumorigenesis in the Min mouse model. The key virulence factor is a secreted metalloprotease called B. fragilis toxin (BFT). BFT induces E-cadherin cleavage, cell rounding, activation of the ${\beta}$-catenin pathway and secretion of IL-8 in colonic epithelial cells. However, the precise mechanism by which these processes occur and how these processes are interrelated is still unclear. E-cadherin form homophilic interactions which tethers adjacent cells. Loss of E-cadherin results in detachment of adjacent cells. Prior studies have suggested that BFT induces IL-8 expression by inducing E-cadherin cleavage; cells that do not express E-cadherin do not secrete IL-8 in response to BFT. In the current study, we found that HT29/C1cells treated with dilute trypsin solution induced E-cadherin degradation and IL-8 secretion, consistent with the hypothesis that E-cadherin cleavage causes IL-8 secretion. However, physical damage to the cell monolayer did not induce IL-8 secretion. We also show that EDTA-mediated disruption of E-cadherin interactions without E-cadherin degradation was sufficient to induce IL-8 secretion. Finally, we determined that HT29/C1 cells treated with LiCl (${\beta}$-catenin activator) induced IL-8 secretion in a dose-dependent and time-dependent manner. Taken together, our results suggest that BFT induced IL-8 secretion may occur by the following process: E-cadherin cleavage, disruption of cellular interactions, activation of the ${\beta}$-catenin pathway and IL-8 expression. However, we further propose that E-cadherin cleavage per se may not be required for BFT induced IL-8 secretion.

• 제어로봇시스템학회논문지
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• 제22권4호
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• pp.276-280
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• 2016

Due to the increasing interest in safety and consistent product quality over a past few decades, demand for effective quality monitoring and safe operation in the modern industry has propelled research into statistical based fault detection and diagnosis methods. This paper describes the application of Hotelling $T^2$ index based Principal Component Analysis (PCA) method for fault detection and diagnosis in industrial processes. Multivariate statistical process control techniques are now widely used for performance monitoring and fault detection. Conventional methods such as PCA are suitable only for steady state processes. These conventional projection methods causes false alarms or missing data for the systems with transient values of processes. These issues significantly compromise the reliability of the monitoring systems. In this paper, a reliable method is used to overcome false alarms occur due to varying process conditions and missing data problems in transient states. This monitoring method is implemented and validated experimentally along with matlab. Experimental results proved the credibility of this fault detection method for both the steady state and transient operations.