• Title/Summary/Keyword: 세정수

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A Study on the Citation Impact of International Collaboration Research for 13 Government-supported Research Institutes of Korea Research Council of Fundamental Science and Technology(KRCF) (국제 공동연구의 인용영향력에 대한 연구 - 기초기술연구회 13개 출연연구기관을 대상으로 -)

  • Lee, June-Young;Shim, We;Ahn, Se-Jung;Kwon, Oh-Jin;Noh, Kyung-Ran
    • The Journal of the Korea institute of electronic communication sciences
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    • v.7 no.6
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    • pp.1353-1362
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    • 2012
  • Many studies have demonstrated that articles from international collaborations are more cited than articles from domestic collaborations. However, difference between the citation impact of international and domestic co-authored papers is supposed to be widened due to the collaboration strategy adopted by individual institute. In short, each institute will show the significantly different citation impact between international and domestic co-authored papers. In this paper, we applied the index of Incremental Ciation Impact(ICI) to identify the different value of citation impact between international and domestic co-authored papers for research institutes of KRCF, results of which will be understood under the strategy of international research collaboration.

Reuse of Petroleum Refinery Wastewater Using Reverse Osmosis Membrane (역삼투막을 이용한 정유산업 폐수 재활용 연구)

  • Hwang, Jong-Sic;Sang, Byoung-In;Yoo, Je-Kang;Lee, Kyu-Hyun;Min, Byoung-Ryul;Kim, Byoung-Sik
    • Membrane Journal
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    • v.4 no.4
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    • pp.213-220
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    • 1994
  • Reverse osmosis(R/O) pilot system, which consists of pretreatments and R/O membranes, was demonstrated to regenerate the petroleum refinery wastewater for the process feedwater supply. Despite of the unsteady quality of the wastewater effluent from the process facilities, relatively high salt rejection of 96~99% was obtained and the product water showed a feasible quality for the use of cooling tower feed water. The results of R/O membrane module cleaning with NaOH solution represented that there was some fouling effects on the membrane performance during the period of test due to the ineffective treatment processes proposed and used in this study.

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Comparison of PCB Surface Treatment Effect Using UV Equipment and Atmospheric Pressure Plasma Equipment (UV 장비 및 대기압 플라즈마 장비를 이용한 PCB 표면 처리 효과 비교)

  • Ryu, Sun-Joong
    • Journal of the Microelectronics and Packaging Society
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    • v.16 no.3
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    • pp.53-59
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    • 2009
  • Low pressure mercury lamp type UV equipments have been widely used for cleaning and modification of PCB surfaces. To enhance the productivity of the process, we newly developed remote DBD type atmospheric pressure plasma equipment. The productivity of both equipments could be compared by measuring surface contact angle for various transferring speed. By the result of the measurement, we could verify that the productivity of the atmospheric pressure plasma be superior to the productivity of the UV equipment. XPS experiments confirmed that the surface effect of the UV and atmospheric pressure plasma processing are similar for each other. Organic contamination level was reduced after the processing and some surface elements were oxidized for both cases. Finally, the atmospheric pressure plasma equipment was adapted to flip chip BGA's flux printing process and it was concluded that the printing uniformity be enhanced by the atmospheric pressure plasma surface treatment.

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Solvent Extraction of Silver (Ag) by Cyanex 301 (Cyanex 301에 의한 은(Ag) 용매추출)

  • Cho, Yeon-Chul;Kang, Myeong-Sik;Ahn, Jae-Woo;Ryu, Ho-jin
    • Resources Recycling
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    • v.25 no.5
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    • pp.50-56
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    • 2016
  • Extraction behaviour of silver from nitric acid solutions by Cyanex 301 as an extractant was examined. Detailed studies have been conducted to evaluate the effect of different variables influencing the extraction such as concentration of nitric acid and extractant, phase ratio(O/A) and synergism of mixed extractant. The extraction behaviour of associated metals namely Ca, Al, Fe, Zn and Sr has been investigated. The extraction results show that Ag can be extracted effectively by Cyanex 301 and selectively extracted from 3.0M $HNO_3$ using 5% Cyanex 301. Impurity metals loaded in organic phase can be effective scrubbed by 4.0M HCl. Finally, pure silver solution can be obtained efficiently by thiourea as a stripping reagent.

The Implementation of Real-Time Vital Sign Information Transmission Monitoring System using TMO (TMO를 이용한 실시간 생체정보 전송 모니터링 시스템 구현)

  • Lim, Se-Jung;Kim, Gwang-Jun
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.1 no.3
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    • pp.33-40
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    • 2008
  • The TMO may contain two types of methods, time-triggered methods(also called the spontaneous methods of SpMs) which are clearly separated from the conventional service methods (SvMs). The SpM executions are triggered upon design time whereas the SvM executions are triggered by service request message from clients. In this paper, we describes the application environment as the patient monitor telemedicine system with TMO structure. Vital sign information web viewer systems is also the standard protocol for medical image and transfer. In order to embrace new technologies as telemedicine service, it is important to develope the standard protocol between different systems in the hospital, as well as the communication with external hospital systems. It is able to apply to remote medical examination and treatment. Through the proper data exchange and management of patient vital sign information, real time vital sign information management will offer better workflow to all hospital employee.

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Recovery of High Purity KI Crystal from Aqueous Waste of Polarizing Film Manufacturing Process (LCD용(用) 편광(偏光)필름제조폐용액(製造廢溶液)으로부터 고순도(高純度) KI결정(結晶) 회수(回收)에 관한 연구(硏究))

  • Kim, Dae-Weon;Jang, Seong-Tae;Choi, Soon-Ryung
    • Resources Recycling
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    • v.21 no.2
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    • pp.53-58
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    • 2012
  • A laboratory study was carried out to recover KI crystals with high purity from a waste solution generated from the production of polarizing film for LCD industry. The waste solution contains 1 to 4% KI, and other impurities such as B, PVA and etc. More than 95% purity of KI crystals were produced through refining process such as vacuum evaporation and fractional crystallization. Most of B compounds and impurities were removed by concentrating the waste solution until KI content reached about 50%. The KI crystals were washed with solvents to remove most of PVA which gave result in producing 99.5% purity of crystals. The overall recovery of KI was about 90% during the concentration process.

Bioactive and Skin-compatible Properties of Silk Sericin (세리신 단백질의 생리활성과 피부친화성 탐색)

  • 이광길;여주홍;이용우;권해용;김종호
    • Journal of Sericultural and Entomological Science
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    • v.43 no.2
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    • pp.109-115
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    • 2001
  • Silk sericin protein was extracted by treatment with enzyme or NaOH solution from raw silk and culled-cocoon shell. The extracted sericin was characterized and examined the functional properties as well as subjective properties for its use as a soap and a body cleaner. The optimum extraction conditions on specimen are NaOH (0.02 wt.%) or enzyme, Flavourzyme 3% under N2 gas. Molecular weights of sericin was decreased by treatment with enzyme, Actinase, from 10,000-30,000 to 2,700-4,200. Sericin showed important bioactive properties, for instance, lowering effect on blood glucose and alcohol. Subjective test of sericin soap and body cleaner showed superior in washability, foamability, and skin hydration, etc., to commercial soap and body cleaner. Therefore, it is thought that silk sericin can be expected as the source of bioactive and skin-compatible materials.

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Mobile Proxy Architecture and Its Practice: Mobile Multimedia Collaboration System (모바일 기기를 위한 프록시 구조와 모바일 멀티미디어 협업 시스템 적용예)

  • Oh, Sang-Yoon
    • Journal of the Korea Society of Computer and Information
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    • v.14 no.7
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    • pp.123-132
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    • 2009
  • The perforrnance and portability of mobile applications can be greatly increased by adopting proxy modiles which exists between the conventional system and the device. When mobile devices collaborate with the conventional computers, there are problems to address: a battery life problem, limited input and output methods, and intermittent wireless connection. Those issues are magnified in the multimedia collaboration environment since it works in a real-time condition and the size of the message in the system is big in many cases. Additionally, because multimedia collaboration system softwares are too heavy and complex for mobile devices, it is veη hard to integrate them with conventional systems. In this paper, we describe our design and its implementation of a novel approach to map events (i.e. messages) using a proxy for mobile applications. We adopt a proxy to provide a content adaptation (i.e. transcoding) where the message contents are customized. Also, we design a mobile version publish/subscribe system to provide communication service for mobile device in loosely coupled and flexible manner. We present our empirical results which show that our design can be efficiently implemented and integrated with a conventional multimedia collaboration system.

An Investigation of the Types of Analogies Generated by Science-Gifted Student, Mapping Errors on the Chromatography, and the Perceptions on Generating Analogy (크로마토그래피 개념에 대해 중학교 과학영재가 만든 비유의 유형과 대응 오류 및 비유 만들기 활동에 대한 인식 조사)

  • Kim, You-Jung;Moon, Se-Jeong;Noh, Tae-Hee
    • Journal of The Korean Association For Science Education
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    • v.29 no.8
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    • pp.861-873
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    • 2009
  • This study investigated the types of analogies generated by science-gifted students, mapping errors on the chromatography, and the perceptions on generating analogy. The subjects were science-gifted eighth-graders (N=68) enrolled at four gifted-education centers in Seoul. Analyses of the results revealed that most science-gifted students represented the analogies using verbal and pictorial forms based on concrete and everyday experiences, and they elaborately explained them including the functional attributes and the causal relationships of the target concept. Science-gifted students selected the analogies having rich similarities or similar structure and principle between the target concept and the analogy as the best of the self-generated analogies. And they used mainly their 'school life' as analogy materials. The results of the mapping test showed that many science-gifted students had mapping errors such as 'failure to map' and 'overmapping'. They were found to have the positive perceptions on generating analogy. The present study will provide the basic information to develop an instructional model in generating analogy in an education program for science-gifted students.

Optimization of highly scalable gate dielectrics by stacking Ta2O5 and SiO2 thin films for advanced MOSFET technology

  • Kim, Tae-Wan;Jo, Won-Ju
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.259-259
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    • 2016
  • 반도체 산업 전반에 걸쳐 이루어지고 있는 연구는 소자를 더 작게 만들면서도 구동능력은 우수한 소자를 만들어내는 것이라고 할 수 있다. 따라서 소자의 미세화와 함께 트랜지스터의 구동능력의 향상을 위한 기술개발에 대한 필요성이 점차 커지고 있으며, 고유전(high-k)재료를 트랜지스터의 게이트 절연막으로 이용하는 방법이 개발되고 있다. High-k 재료를 트랜지스터의 게이트 절연막에 적용하면 낮은 전압으로 소자를 구동할 수 있어서 소비전력이 감소하고 소자의 미세화 측면에서도 매우 유리하다. 그러나, 초미세화된 소자를 제작하기 위하여 high-k 절연막의 두께를 줄이게 되면, 전기적 용량(capacitance)은 커지지만 에너지 밴드 오프셋(band-offset)이 기존의 실리콘 산화막(SiO2)보다 작고 또한 열공정에 의해 쉽게 결정화가 이루어지기 때문에 누설전류가 발생하여 소자의 열화를 초래할 수 있다. 따라서, 최근에는 이러한 문제를 해결하기 위하여 게이트 절연막 엔지니어링을 통해서 누설전류를 줄이면서 전기적 용량을 확보할 수 있는 연구가 주목받고 있다. 본 실험에서는 high-k 물질인 Ta2O5와 SiO2를 적층시켜서 누설전류를 줄이면서 동시에 높은 캐패시턴스를 달성할 수 있는 게이트 절연막 엔지니어링에 대한 연구를 진행하였다. 먼저 n-type Si 기판을 표준 RCA 세정한 다음, RF sputter를 사용하여 두께가 Ta2O5/SiO2 = 50/0, 50/5, 50/10, 25/10, 25/5 nm인 적층구조의 게이트 절연막을 형성하였다. 다음으로 Al 게이트 전극을 150 nm의 두께로 증착한 다음, 전기적 특성 개선을 위하여 furnace N2 분위기에서 $400^{\circ}C$로 30분간 후속 열처리를 진행하여 MOS capacitor 소자를 제작하였고, I-V 및 C-V 측정을 통하여 형성된 게이트 절연막의 전기적 특성을 평가하였다. 그 결과, Ta2O5/SiO2 = 50/0, 50/5, 50/10 nm인 게이트 절연막들은 누설전류는 낮지만, 큰 용량을 얻을 수 없었다. 한편, Ta2O5/SiO2 = 25/10, 25/5 nm의 조합에서는 충분한 용량을 확보할 수 있었다. 적층된 게이트 절연막의 유전상수는 25/5 nm, 25/10 nm 각각 8.3, 7.6으로 비슷하였지만, 문턱치 전압(VTH)은 각각 -0.64 V, -0.18 V로 25/10 nm가 0 V에 보다 근접한 값을 나타내었다. 한편, 누설전류는 25/10 nm가 25/5 nm보다 약 20 nA (@5 V) 낮은 것을 확인할 수 있었으며 절연파괴전압(breakdown voltage)도 증가한 것을 확인하였다. 결론적으로 Ta2O5/SiO2 적층 절연막의 두께가 25nm/10nm에서 최적의 특성을 얻을 수 있었으며, 본 실험과 같이 게이트 절연막 엔지니어링을 통하여 효과적으로 누설전류를 줄이고 게이트 용량을 증가시킴으로써 고집적화된 소자의 제작에 유용한 기술로 기대된다.

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