• The monthly packaging world
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• s.362
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• pp.83-92
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• 2023

• Proceedings of the Korea Contents Association Conference
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• 2010.05a
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• pp.25-27
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• 2010

인터넷 보급률이 증가함에 따라 동시 접속자 수가 크게 증가한 요즘 기존에 소규모 시스템 및 소수의 사용자에게 적합한 클라이언트와 서버 방식인 2-티어 환경에서의 시스템은 성능저하의 요인이 되었고 이는 대규모 프로젝트 수행시 좀더 높은 성능으로 처리하게 되었다. 본 논문에서는 대규모 프로젝트의 최적의 성능 및 유지보수 편의성을 제공하기 위해 닷넷 리모팅 서비스와 스마트 클라이언트를 기반으로 한 3-티어 환경에서의 학사시스템 아키텍쳐를 설계하였다.

• Proceedings of the Korea Contents Association Conference
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• 2007.11a
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• pp.255-258
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• 2007

WLCG/EGEE project has a main goal of providing application scientists with access to a geographically distributed computing Grid infrastructure. Currently, WLCG/EGEE infrastructure is the world's largest Grid infrastructure, providing over 20,000 CPUs and about 3 PB disk at 200 international sites and used by over 9 application domains including LHC experiments from high-energy physics. This paper addresses the design and construction of WLCG/EGEE tier-2 propelled by international collaboration with EGEE-II project.

• Journal of the Korea Society of Computer and Information
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• v.16 no.2
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• pp.101-111
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• 2011

A new MAC protocol, MT-MAC(Multi-Tier Medium Access Control) by name, is proposed for dense sensor networks. Depending on the density of nodes in a virtual cluster, the cluster header performs the splitting to several tiers in nodes of virtual cluster. MT-MAC split the tiers to use modfied-SYNC message after receiving the beacon message from the cluster header. Because only the sensor nodes in the same tier communicate each other, less power is consumed and longer network life time is guaranteed. By a simulation method with NS-2, we evaluated our protocol. In dense nodes environments, MT-MAC protocol shows better results than S-MAC in terms of packet delivery rates throughput and energy consumption.

• Environmental and Resource Economics Review
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• v.30 no.3
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• pp.471-501
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• 2021

We measure Environmental Efficiency (EE) based on CO₂ in four income groups from 1998 to 2018, using the Meta Stochastic Frontier Analysis method by Input Distance Function. Our results showed that economic growth and energy consumption would increase carbon dioxide emissions, and increasing labor and capital input will reduce it. Moreover, we compared Group Environmental Efficiency (GEE), Meta Environmental Efficiency (MEE), and Environmental Gap Ratio (EGR). The results showed that GEEs were be overestimated. Furthermore, the MEE showed a downward trend during this period. The lower-middle-income group had the highest EGR performance. High-income and upper-middle-income groups showed less efficiency in MEE and EGR. To improve environmental efficiency, we must reduce fossil fuels and find more scientific and technological ways to solve existing environmental problems as soon as possible.

• Analytical Science and Technology
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• v.19 no.3
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• pp.244-254
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• 2006

Flame retardants are added to prevent catching fire and to slow down the burning process. PBDEs are known to affect thyroid hormones and hormone disruption. The aim of this study was to propose a manual for determination of PBDEs, and investigate the accumulation of PBDEs(BDE-28, 47, 99, 100, 153, 154 and 183) in fish&shellfish and human milk samples. Pre-treatment for PBDEs determination, alkali digestion and L-L(Liquid-Liquid) extraction method could be applied to fish and shellfish. When Multi-layer column was used for cleaning up the sample, 50 mL of hexane and 100 mL of hexane:dichloromethane(9:1) solutions were used for pre- and post-elution, respectively. Activated-carbon column was optimized by a 100 mL of hexane:dichloromethane(3:1). The result of fish, highest concentration was detected in flatfish, 890 pg/g(wet weight). The other side, lowest concentration was detected in pollack, 40 pg/g(wet weight). The result of breast milk, PBDEs was detected 2,580 and 3,600 pg/g(lipid weight) from breast milk of Seoul and Juju, respectively. BDE-153 and 183 were not detected in all samples. There was no difference in PBDEs level was not difference between first and second delivery. In this study, we could find that PBDEs level in Korea is lower than other countries.

• 프린팅코리아
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• v.11 no.5
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• pp.98-99
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• 2012

에이스기계(주)(대표이사 이철)는 지난 4월 3일 고양시 킨텍스 1전시장 2층에서 신제품 및 신기술 발표회를 개최했다. 인쇄 및 포장업계 대표, 부서장, 접착기장 등 200여명이 참석한 이번 발표회에서는 시그니처 이글, 시그니처 오리엔트, 시그팩커, 인렛 스포트, 시그피더, 티어 테이핑기계 등이 소개됐다. 신제품 발표 외에도 접착기의 효율적인 관리방법에 대한 교육 및 접착기장 기술 인력 확충 방안에 대한 토론도 진행됐다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.4
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• pp.733-737
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• 2007

The object of this paper is to propose a method to solve resulting heat in using numerous modulized watt-class LEDs in MCPCB as lighting device. To use LED for lighting, the chip needs to have a large capacity, resulting in extra heat in P-N connection area. To solve this problem, a Pottier Module, heat-sink panel and a fan was installed to measure variations in the temperature. Additionally, temperature variation characteristics were observed according to the heat conductor panel connecting cooling module and heat-sink panel, insulator and thermal grease. As a result, the type and amount of heat-sink panel was the most important facto. The fan would effect the temperature by max. $18[^{\circ}C]$ while other materials affected the temperature by $2{\sim}3[^{\circ}C]$, showing significant difference.

• Journal of Technology Innovation
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• v.17 no.2
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• pp.131-158
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• 2009

We examine the effects of environmental or organizational factors on the performance of TLOs(technology transfer offices) in the PRIs(Public research institutes) using SFA(Stochastic Frontier Analysis), a technique for estimating the efficiency of DMUs(decision making units). In SFA, independent variables are assumed to determine the efficient production technique(production frontier) or affect the efficiency of DMUs. Previous researchs show that input variables such as number of personnel, R&D expenditure affect the production frontier while environmental or organizational variables affect the efficiency. We tried to estimate various types of models to find out whether environmental or organizational variables affect output variables differently from the previous research. Main empirical findings are as follows. First, R&D expenditure tends to increase all output variables considered. Second, environmental factors such as type of institutions and location of institutions affect the level of outputs. Third, organizational factors such as reward system for technology transfer also appear to affect the output variables. Fourth, environmental or organizational variables affect the production frontier directly rather than affect the efficiency of DMUs. Lastly, the efficiency of each DMU appear to be 1 or near to 1. Since almost all DMUs are equally efficient, it may not be effective to evaluate technology transfer activities of PRIs by efficiency criteria. We believe that this research should be complemented by additional data. More general types of production function need to be considered, and new techniques with concepts like output distance functions need to be developed to analyse multiple outputs simultaneously.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.1
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• pp.1-11
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• 2012

This paper reports on a prototype cooling garment applying a cooling module. The cooling module was composed of a Peltier device, a cold sink, a heat sink and two fans. A constant box was used to evaluate the cooling effect of the module. Two cooling modules were attached on each side of the garment. The wear trial was conducted using 10 male subjects in an environmental chamber maintained at $30{\pm}0.5^{\circ}C$, $50{\pm}5%$RH. Subjective sensations of thermal, humidity, and comfort were surveyed. Statistical package SPSS12.0 was used for the t-test and the Wilcoxon signed-rank test. The results showed that most effective cooling module decreased the temperature of the constant temperature box by $-4.9^{\circ}C$. The micro-temperature of the cooling garment with a Peltier device was lower than the control garment during the exercise. In particular, the chest skin temperature was $1.5^{\circ}C$ lower with the cooling garment than the control. The maximum temperature difference was $-2.57^{\circ}C$ on the sides of the $1^{st}$ layer. Subjective thermal sensation from wear trials of the Peltier device attached garment was lower than the control garment. Subjects felt more comfortable with the cooling garment in almost all the periods.