• Journal of Environmental Science International
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• v.21 no.4
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• pp.411-419
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• 2012

In this study, Ibuprofen (IBP) degradation by the photo catalytic process was investigated under various parameters, such as UV intensity, optimum dosage of $TiO_2$, alkalinity, temperature and pH of bulk solution. The pseudo-first order degradation rate constants were in the order of $10^{-1}$ to $10^{-4}min^{-1}$ depending on each condition. The Photocatalytic IBP degradation rate increased with an increase in the applied UV power. At high UV intensity a high rate of tri-iodide ($I_3{^-}$) ion formation was also observed. Moreover, in order to avoid the use of an excess catalyst, the optimum dosage of catalyst under the various UV intensities (30 and 40 W/L) was examined and ranged from approximately 0.1 $gL^{-1}$. The photo catalytic IBP degradation rate was changed depending on the alkalinity and temperature and pH in the aqueous solution. This study demonstrated the potential of photo catalytic IBP degradation under different conditions.

• Journal of Information Technology and Architecture
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• v.10 no.2
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• pp.197-209
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• 2013

This study analyzes the nature of consumers and smart phones as well as its limitations that domestic mobile communication companies confront. According to the analysis results, emerging technologies such as 5G communication, pervasive computing, augmented reality, and big data seem to have significant effect on the ICT ecosystem in the near future. Based on the results, this study suggests four counterstrategies for domestic mobile communication companies: big data strategy, preparation of things acting as a main communication agent, new service platform development, and 'total life care service provider' strategy.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.5
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• pp.1-12
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• 2009

This research was initiated to investigate the revegetation characteristics under the seeding amount treatments of cool-season turfgrasses on the disturbed slope. 4 different seeding amounts of cool-season turfgrasses (0.0 $g/m^2$, 1.5 $g/m^2$, 3.0 $g/m^2$, 6.0 $g/m^2$) with the same seeding amounts of native woody (Rhus chinensis, Albizzia julibrissin) and herbaceous plants (Lotus corniculatus var. japonicus, Dianthus sinensis, Aster yomena) were treated with 3 replications on the experimental disturbed slope. Data such as soil hardness (mm), moisture content (%), surface coverage rate (%), the number of each germinating plant and plant height were analyzed. There were no statistic differences observed in the soil hardness and the soil moisture content while a significant difference was observed in the surface coverage rates. The surface coverage rates were higher in 3.0 $g/m^2$ and 6.0 $g/m^2$ plots compared to the rest two plots of cool-season turfgrasses. However, the emergence of native woody and herbaceous plants was relatively low in 3.0 $g/m^2$ and 6.0 $g/m^2$ plots of high seeding amounts of cool-season turfgrasses. This result indicated that high seeding amounts of cool-season turfgrasses could decrease the emergence of native woody and herbaceous plants. We concluded that 1.5 g~3.0 $g/m^2$ seeding amounts of cool-season turfgrasses was optimum level for the balanced emergence of cool-season turfgrasses, native woody and herbaceous plants in the viewpoint of the ecological disturbed slope revegetation.

• ETRI Journal
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• v.39 no.4
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• pp.525-534
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• 2017

A hardware-acceleration architecture that separates virtual network functions (VNFs) and network control (called HSN) is proposed to solve the mismatch between the simple flow steering requirements and strong packet processing abilities of software-defined networking (SDN) forwarding elements (FEs) in SDN/network function virtualization (NFV) architecture, while improving the efficiency of NFV infrastructure and the performance of network-intensive functions. HSN makes full use of FEs and accelerates VNFs through two mechanisms: (1) separation of traffic steering and packet processing in the FEs; (2) separation of SDN and NFV control in the FEs. Our HSN prototype, built on NetFPGA-10G, demonstrates that the processing performance can be greatly improved with only a small modification of the traditional SDN/NFV architecture.

• Electronics and Telecommunications Trends
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• v.36 no.4
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• pp.1-12
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• 2021

The competition to lead the next generation of mobile technologies, 6G, is underway while the deployment of 5G has not been implemented worldwide. ITU-R plans to develop technical requirements and standards after completing the 6G Vision by 2023. It can be considered too early to have a concrete view of the 6G core network architecture from this timeline. However, major stakeholders have started making their presence felt by publishing their views. From updated analysis on the technology and service trends proposed, we present a list of research directions on 6G core network from several perspectives: distribution of network functions to nearer edge locations; future fixed-mobile convergence, including low earth orbit satellites; highly-precise QoS guarantee; supporting an extremely wide variety of service requirements; AI-native automation and intelligence; and aligning with the evolution of radio access network.

• Journal of the Korean Solar Energy Society
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• v.33 no.1
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• pp.73-78
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• 2013

Hexadecane and exfoliated graphite nanoplate (xGnP)composite was prepared as a shape-stabilized phase change material (SSPCM) in a vacuum to develope thermal energy storage. The Hexadecane as an organic phase change material (PCM) is very stable against phase separation of PCM and has a melting point at $18^{\circ}C$ that is under the thermally comfortable temperature range in buildings. The xGnP is a porous carbon nanotube material with high thermal conductivity. Scanning electron microscope (SEM) and Fourier transformation infrared spectrophotometer (FT-IR)were used to confirm the chemical and physical stability of Hexadecane/xGnP SSPCM. In addition, thermal properties were determined by Deferential scanning calorimeter(DSC) and Thermogravimetric analysis (TGA). The specific heat of Hexadecane/xGnPSSPCM was $10.0J/g{\cdot}K$ at $21.8^{\circ}C$. The melting temperature range of melting and freezing were found to be $16-25^{\circ}C$ and $17-12^{\circ}C$. At this time, the laten heats of melting and freezing were 96.4J/g and 94.8J/g. The Hexadecane was impregnated into xGnP as much about 48.8% of Hexadecane/xGnP SSPCM's mass fraction.

• Journal of The Korea Institute of Healthcare Architecture
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• v.16 no.4
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• pp.33-40
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• 2010

Gross-to-net ratio is the important factor determining size of the building. However it was determined as the empirical method without the exact basis in the existing planning. This paper proposes more accurate methods for determining the gross-to-net ratio of architectural planning in general hospital. This paper analyzes the difference of gross-to-net ratio according to the various conditions and presents the elements of influencing on gross-to-net ratio. These elements is evaluated by applying in the typical hospital case. In conclusion, gross-to-net ratio is influenced by the accuracy of the space program, form type of the space and correspondence potential about the internal variation. In addition, This study has proved that empirical approach is a standard of minimum area.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.1
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• pp.28-35
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• 1998

Six soil compositions with three seeding rates were evaluated for influence on germination, coverage, height and sod development of Phragmites japonica. 1. Germination was high on peat, vermiculite and bark as compared with on peatmoss and sandy loam. 2. Covering rate was high within 2 months when seeded at 9g/$m^2$, but became same within 3 months afterwards when seeded at 3,6 and 9g/$m^2$, respectively. 3. Sod was highly developed on peat and bark treatments whereas Sandy loam, peatmoss and vermiculite treatments didn't develop sod. 4. Sod grown on bark weighed light and, therefore, was suggested best from a dealing cost point of view. 5. Cutting at 10 cm height didn't influence on sod development regardless of soil compositions.

• Electronics and Telecommunications Trends
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• v.31 no.6
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• pp.88-96
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• 2016

5G RAN은 4G가 진화된 무선기술(evolved E-UTRA)과 5G 무선기술(New Radio, NR)을 모두 지원하는 새로운 무선액세스 네트워크(New RAN)이며, 코어 네트워크 (EPC and NGC)과 접속되어 5G 시스템(NextGen System)을 구성한다. 본고에서는 5G RAN(Radio Access Network,)을 대상으로, RAN 시설 배치 시나리오, RAN과 CN 간 기능 분배 및 인터페이스, 프런트-홀 네트워크의 전송 용량 및 지연, New RAN과 E-UTRA 간 모빌리티 시나리오 등에 대한 표준 이슈를 살펴본다. 마지막 절에선 RAN의 네트워크 슬라이싱 지원 방안으로 상위레벨 개념의 구조와 절차를 정리한다. 본 문서는 3GPP RAN3 그룹의 기술보고서(TR 38.801)와 SA2 기술보고서(TR 23.799)를 바탕으로 작성되었다.

• Electronics and Telecommunications Trends
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• v.31 no.1
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• pp.1-13
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• 2016

5G는 2020년 이후를 위한 4G 다음 세대의 이동통신으로 검토가 시작되었으나, 이동통신의 연장선이 아닌 이동통신과 네트워크의 새로운 패러다임으로 인식되고 있다. 5G는 이동통신, 인터넷, 클라우드가 통합되는 네트워크 + IT 환경이 될 것이며, 기술, 서비스, 타 산업과의 관계, 시장, 사업구도 등 모든 면에서 새로운 변화가 예상된다. 본고에서는 2016년을 기점으로 본격화될 5G의 아키텍처에 대한 최근 연구동향을 정리한다. 아키텍처의 범위는 Radio Access Network(RAN) 아키텍처, 코어네트워크 아키텍처, 가상화/프로그래머블 아키텍처, 네트워크 관리 자동화/지능화 아키텍처 등이다. 주요 연구프로젝트, 통신사업자, 산업체 등에서 제안한 5G 아키텍처 현안들을 각각 정리한다.