• Journal of KIISE:Computer Systems and Theory
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• v.36 no.6
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• pp.476-487
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• 2009

The virtual memory system in 4.4 BSD operating systems exploits a clustering scheme to reduce disk I/Os in paging out (or flushing) modified pages that are intended to be replaced in order to make free rooms in memory. Upon the page out of a victim page, the scheme stores a cluster (or group) of modified pages contiguous with the victim in the virtual address space to swap disk at a single disk write. However, it fails to find large clusters of contiguous pages if applications change pages not adjacent with each other in the virtual address space. To address the problem, we propose a new clustering scheme called Multiple-Object Clustering (MOC), which together stores multiple clusters in the virtual address space at a single disk write instead of paging out the clusters to swap space at separate disk I/Os. This multiple-cluster transfer allows the virtual memory system to significantly decrease disk writes, thus improving the page-out performance. Our experiments in the FreeBSD 6.2 show that MOC improves the execution times of realistic benchmarks such as NS2, Scimark2 SOR, and nbench LU over the traditional clustering scheme ranging from 9 to 45%.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.4
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• pp.124-130
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• 2008

Automatic layout decomposition techniques have been developed for double patterning technology (DPT). As CMOS manufacturing process scales down to 45nm and below, lithography resolution needs to be improved. DPT has been proposed to enhance the limitation of conventional lithography, by decomposing the layout design into two masks to relax the minimum spacing requirement. However, it is not always possible to decompose a layout into two masks. We have developed new automatic stitching techniques to resolve this problem. Experimental results show that the suggested techniques are promising in decomposing layouts for DPT.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.1
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• pp.81-86
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• 2016

In this paper, we present multi-channel authentication based security card design. Since this security card is written on the transparent paper, security information is extracted by overlaying the card with smartphone screen. This method removes the limitations of physical layout in previous security card and improves the security level. Furthermore, our security card is secure when our card is exposed to malicious users.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.6
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• pp.440-447
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• 2001

This study investigate experimentally the effect of in height, thickness, and clearance on the boiling heat transfer. The heat surfaces having copper fin array is tested for pool boiling. The gas-liquid exchange interference is investigated based on fin array clearance. These test results can be applied to the design of tube bundle system. The fin height of 2 mm is found to be effective. Effects of heat transfer promotion reaches the highest level when the fin clearance is 0.5mm. Also, heat flux is increased when the fin thickness is smaller. But0.2 mm fin thickness is highly recommended.

• TTA Journal
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• s.139
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• pp.40-43
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• 2012

주로 컴퓨터 자원(Platform, HDD, CPU)의 가상화를 통한 IT 인프라 관리 및 아웃소싱의 효율성을 추구하던 클라우드 컴퓨팅이 이제는 다양한 서비스 분야로 전환되고 있다. 심지어 사용자의 개인 데이터, 홈 가전기기, 헬스 기기 등의 모든 디지털화된 IT 자원이 스마트 폰, 태블릿 PC, IP-TV 중심의 N-Screen 등의 사용자 단말 기술들과 연계 및 진화하여 더욱 편리한 디지털 라이프의 변화를 주도하고 있다. 따라서 본 특집에서는 더욱 발전하는 클라우드 컴퓨팅의 주요 분야들 - 모바일 클라우드, DaaS(Desktop as a Service: 데스크톱 클라우드), 공공 부문의 SLA(Service Level Agreement), 퍼스널 클라우드 보안과 프라이버시 - 대해 기술적 동향과 이슈 등을 고찰하고자 한다. 특히 작금의 국제적 표준화가 ITU-T, ISO에서 조직과 체계를 구체적으로 마련하고 2012년부터는 본격적인 경쟁에 들어가는 중요한 시대적 위치에 있으므로 본 특집을 통해 국내 연구자 및 개발자들에게 표준화된 기술 및 서비스 개발에 동기를 부여하고자 한다. 본 특집을 기획하면서 클라우드 컴퓨팅은 IT의 인프라에서 응용까지 연계되어 서비스 산업의 좋은 모델로서 국가적 경쟁력을 끌어올릴 수 있는 중요한 기술임이 자명하며, 단기적으로 끝나는 기술이 아님을 다시 한 번 확인할 수 있는 좋은 기회로 산업의 많은 분야에 뿌리 깊이 내려지길 기대해 본다. 이를 위해 기업과 국가의 지속적인 개발과 지원에 대한 결정이 그 어느 때보다 필요하다.

• Korean Journal of Biological Psychiatry
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• v.27 no.2
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• pp.84-93
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• 2020

Objectives The purpose of the present study was to examine the relationship between the chronotype and the burnout, so we investigated the mediating effects of the mediators such as perceived stress, stress response, and depression. Methods Employees working at Incheon Customs conducted a mental health self-examination through the internet. Among them, 174 people who agreed to the mental health survey participated in the study. Participants completed questionnaires including Composite Scale of Morningness (CSM), Center for Epidemiological Studies-Depression Scale (CES-D), Perceived Stress Scale (PSS), Stress Response Inventory (SRI), Maslach Burnout Inventory-General Survey (MBI-GS). Results Our results showed a higher degree of CES-D, SRI, exhaustion, and cynicism in evening and intermediate type compared to morning type, and a higher degree of professional efficacy in morning type compared to intermediate type. CSM was shown to have a direct effect on exhaustion and indirect effect through CES-D and SRI. CSM also had a direct effect on professional efficacy and had an indirect effect through the CES-D. However, CSM was found to have only indirect effects through the SRI for Cynicism. Conclusions In this study, individuals with evening type tend to experience a high degree of burnout (exhaustion, cynicism and professional efficacy) through the mediation effect of depression and stress response. Further study is necessary to reveal the effect of management of the depression and stress response in the employee with evening type.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.8 no.4
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• pp.527-536
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• 1996

Convective nucleate boiling and burnout heat flux have been studied on a flat, downward facing, constant heat flux surface cooled by an impinging water jet. The tests are progressed from low, nonboiling power to high, burnout heat flux power. The jet velocity and the subcooling do not affect the nucleate boiling curve of $q{\sim}{\Delta}T_{sat}$ diagram, but the supplementary water height affects the curve. For the case of dimensionless height of supplementary water S/D=1, the boiling curve shift to the heigher heat flux than that of S/D=0 or S/D=2. Burnout heat flux is enhanced with increasing jet velocity and subcooling. Also. by using the supplementary water(S/D=1 or S/D=2), burnout heat flux is larger than that of the simple water jet(S/D=0). A generalized correlation for the burnout heat flux data in the present boiling system with an impinging water jet is successfully evolved.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.2
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• pp.204-210
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• 2005

This paper presents online identification algorithm for TSK fuzzy model. The proposed algorithm identify structure of premise part by using distance, and obtain the parameters of the piecewise linear function consisting consequent part by using recursive least square. Only input space was considered in Most researches on structure identification, but input and output space is considered in the proposed algorithm. By doing so, outliers are excluded in clustering effectively. The existing other algorithm has disadvantage that it is sensitive to noise by using data itself as cluster centers. The proposed algorithm is non-sensitive to noise not by using data itself as cluster centers. Model can be obtained through one pass and it is not needed to memorize many data in the proposed algorithm.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.1
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• pp.131-142
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• 2004

When the cotton/polyester fiber mixed fabrics were treated with ferrous sulfate and oxalic acid for burn out finishing, it was examined how the effects of process conditions as concentration of burn out agents, temperature, time and pressure act onto the properties of polyester ground fabrics. The results are as follows. The effect of burn out finishing by pressure was greated in 3 kgf/$\textrm{cm}^2$. The properties as white index and tensile strength of polyester ground fabrics were decreased according as processing concentration, temperature time increases. The shrinkage was increased according as processing concentration, temperature time increases. The optimum condition of burn out agents to ferrous sulfate was 30% concentration, 150$^{\circ}C$, 1 min, 3 kgf/$\textrm{cm}^2$ and to oxalic acid was 10% concentration, 110$^{\circ}C$, 1min, 3 kgf/$\textrm{cm}^2$. And the optimum of ferrous sulfate and oxalic acid used in combination was 10% ferrous sulfate and 7% oxalic acid, 110$^{\circ}C$, 1 min., 3 kgf/$\textrm{cm}^2$.

• Journal of the Korea Society of Computer and Information
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• v.15 no.7
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• pp.1-10
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• 2010

The power of computational Grid resources can be utilized on users desktop by employing workflow managers. It also helps scientists to conveniently put together and run their own scientific workflows. Generally, stage-in, process and stage-out are serially executed and workflow systems help automate this process. However, as the data size is exponentially increasing and more and more scientific workflows require multiple processing steps to obtain the desired output, we argue that the data movement will possess high portion of overall running time. In this paper, we improved staging time and design a new scheduler where the system can execute concurrently as many jobs as possible. Our simulation study shows that 10% to 40% improvement in running time can be achieved through our approach.