• Title/Summary/Keyword: Separation media

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Development of the Water-borne Separation Media Polymer for a Moving Historic Sites (자기분산형 수용성 에폭시를 이용한 유구 이전용 박리제의 개발)

  • Han, Won-Sik;Hong, Tae-Kee;Lim, Sung-Jin;Wi, Koang-Chul
    • Journal of Conservation Science
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    • v.25 no.2
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    • pp.171-178
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    • 2009
  • When we considered the superior ability of the semi-water soluble urethane 1st transcription and final epoxy products, the stability for moving historic sites depend on physical properties and the peel off state of separation media. In this paper, we synthesised three type of water-borne epoxy solution without using a surfactant, and investigated the peel off state, physical properties, and the state between urethane surface and epoxy surface after exfoliation. The life time of water-borne separation media is over the 60 days. When it is used the 30% solution of water-borne separation media, it made good separation of urethane pre-products surface and epoxy final product surface and no color change. The separation tension pressure is about 15~50 kg/$cm^2$ and there is no surface whitewash phenomenon. We suggest that this water-borne epoxy will be best material as separation media of low viscosity type.

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Role of Crossflow Module Media in Gas-liquid-solid Separation and Biomass Retention in Hybrid Anaerobic Filter (교차흐름식 모듈 충전 hybrid 혐기성여상의 기·액·고 분리능 및 슬러지보유능)

  • Chang, Duk;Chae, Hee-Wang;Bae, Hyung-Suk;Chung, In;Han, Sang-Bae;Hur, Joon-Moo;Hong, Ki-Ho
    • Journal of Korean Society of Water and Wastewater
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    • v.23 no.6
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    • pp.769-778
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    • 2009
  • Performances and internal behaviors of the upflow hybrid anaerobic filters treating a dairy wastewater were analyzed to identify the functions and roles of the modular crossflow media and sludge bed layer and to discover their interrelationship in the filter. The media could perform independent biological and physical separation role without buildup of sludge bed, while the role of sludge bed was dependent on the function of the media. The filter packed with the crossflow media did not necessarily require the formation of sludge bed when treating a dairy wastewater. Biological contribution of the media was controlled by that of biologically active sludge bed complementing mutually each other. The gas-liquid-solid separation capability of the media was indispensible to ensure the active biological role of sludge bed, since sludge bed buildup without the media had no independently effective biological function. It was believed that the filter in itself could also function as a selector for physical gas-liquid-solid separation resulting in selectively concentrating particles with superior settleability in sludge bed. The sludge bed in the filter played a key role in the physical solids capture from influent as well as biological organics removal.

Protection of Incumbent Services and Its Impact on Coverage of TV Band Device Networks in TV White Space

  • Kang, Kyu-Min;Park, Jae Cheol;Cho, Sang-In;Park, Seungkeun
    • ETRI Journal
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    • v.38 no.1
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    • pp.112-122
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    • 2016
  • This paper presents a set of candidate regulatory requirements for TV band devices (TVBDs) in the Rep. of Korea. To guarantee the protection of incumbent services, especially digital TV (DTV) and wireless microphones, in TV frequency bands, we suggest minimum separation distances of TVBDs from the noise-limited contour according to incumbent users and TVBD types. This paper also deals with multiple sets of separation distances of a co-channel TVBD network from a DTV protected contour on the basis of the radio propagation characteristics of different geographic areas to make good use of TV white space (TVWS) and safely protect the DTV service. We present a low-power transmission mode of TVBDs and the relevant separation distances for small-cell deployment. The service coverage reduction ratio of a TVBD network is investigated in the presence of DTV interference in four geographic areas. The TVWS field verification results, conducted on the island of Jeju (Rep. of Korea), show that incumbent services operate well without harmful interference from neighboring TVBDs with the proposed separation distances.

Analysis of Double-Stranded DNA Fragments by Capillary Electrophoresis Using Entangle Polymer Solutions in Uncoated Fused Silica Capillary Columns

  • Lee, Jong-Jin;Lee, Kong-Joo
    • BMB Reports
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    • v.31 no.4
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    • pp.384-390
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    • 1998
  • DNA fragments (51-587 bp) were separated by capillary electrophoresis using entangled polymer, hydroxyethylcellulose, in uncoated fused silica capillary columns. The factors affecting the separation of DNA fragments with hydroxyethylcellulose media were evaluated, i.e., the concentration of buffer and entangled polymer, effects of additives (methanol, ethidium bromide, EDTA), temperature, and injection methods. Maximum performance was obtained by adding 5% methanol in 0.5% hydroxyethylcellulose solution at $30^{\circ}C$. Addition of methanol in polymer media increased the resolution of small size DNA fragments (< 100 bp). On the other hand, addition of ethidium bromide and EDTA, which are commonly used in conventional DNA separation, reduced the resolution of DNA fragments in the polymer solution. It turns out that the separation behavior of DNA in entangled polymer is more sensitive to the running condition compared to that in polyacrylamide gel-filled capillary, but the reproducibility of DNA separation in entangled polymer is reliable.

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Study on the Peel off Style Low Viscosity Epoxy and Separation Media for a Moving Historic Sites (유구 이전 전용 저점도형 에폭시와 박리제에 관한 연구)

  • Han, Won-Sik;Hong, Tae-Kee;Park, Gi-Jung;Lim, Sung-Jin;Wi, Koang-Chul
    • Journal of Conservation Science
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    • v.24
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    • pp.37-42
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    • 2008
  • Stability of the moving historic sites have something to do with the degree of easiness of work as well as physical property of polymer product. These agents should be able to use without the effect of outer environments like water or low temperature and must have stability during progress of working the peel off Urethane pre-product from Epoxy surface. So, we synthesized low viscosity epoxy resin and hardener with best physical quality and separation media for the moving of historical sites. These products have very good tension strength, adhesion strength, low viscosity and various physical properties that the users want. Particularly, separation media products have good separation of Urethane pre-products surface and Epoxy final product surface.

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A Study on the Educational Space in Religeous Buildings (교회(敎會)의 교육공간(敎育空間)을 위한 매체(媒體)센터 시설(施設)에 관(關)한 연구(硏究))

  • Kang, Eun-Hee
    • Journal of the Korean Institute of Educational Facilities
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    • v.2 no.1
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    • pp.7-14
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    • 1995
  • The importance of church school education is becoming more emphasized. To maximize the effectiveness and efficiency of church school education, frequent utilization of instructional media is more desirable. Systematic approach to media utilization will be developed by the extabilishment of church media center. The purpose of this study was to review the concept and components of church media center and to survey the current status and hope for the facility of church media center. For the survey the 400 questionnaries were distributed to pastors or missionaries who are responssible for education, or personnels in church media center in Korea. The churches that they belong to have above approximately 500 church members. Among the distributed questionnaires, the 202 were collected. The results of the survey are as follows. The printed media and the AV media were managed separately in most churches. Many church media center was shared the space with other programs. The space was allocated mainly for storage. Most respondants hoped that they have a variety of areas in their churches. Many church media center have no separation between the area for the adults and that for children. However, most respondants hoped the separation of that areas. Followings are suggestions for the plan of church media center facilities. The space only for the church media center should be allocated. Church media center should be located in the first floor of the building as soon as possible. (If there is elevators in the building, it may be located above first floor). If enough space for the church media center is allocated, the areas for the adults and children should be separated by partitions or separate room. The space should consist of various areas like circulation area, reading area, working area for the personnel, production area, and storing area.

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Acculturation Strategies and Media Contents (재미한인의 문화변용전략과 미디어 콘텐츠)

  • Park, Cheong Yi;Sung, Jiyeon
    • The Journal of the Korea Contents Association
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    • v.12 no.12
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    • pp.479-488
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    • 2012
  • The study examined acculturation patterns of Korean-Americans living in Portland, USA and their relationship to the consumption of media contents. Under the academic guidance of Berry's acculturation model, the four strategies of acculturation model were extensively inquired that immigrants and sojourner would adopt in host culture: Integration, Assimilation, Separation and Marginalization. Furthermore, how differently the four acculturation modes are related to media contents was examined. For this study, the survey questionnaires were administered among Korean Americans in Portland, USA. The total 371 data were collected and analyzed. The result indicated that 1) they preferred integration(M=4.57) and separation modes(M=4.49) over assimilation (M=2.92); 2) as separation tendency increased, the preference of Korean contents over American contents increased while as assimilation tendency increased, the preference of American contents over Korean contents; 3) high assimilation persons consumed more news than entertainments in American media contents. Compared to it, high separation persons used more entertainments than news in American media contents and more news than entertainments in Korean media contents.

The Finite Element Analysis and Experiment of Flexible Media Separation Mechanism (유연매체 분리기구의 유한요소해석과 실험)

  • Yoon, You-Hoon;Baek, Yoon-Kil;Yoon, Joon-Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.05a
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    • pp.322-325
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    • 2005
  • The separation mechanism is installed to separate a note one by one from the stacked notes and the overlap type, one of separation mechanism, has been used a lot in financial equipments like ATM. This paper has compared and estimated analysis results using finite element method with experimental results over various parameters such as conditions of note, overlap value, roller shapes, which affect the friction force (resistance) exerting on notes between rollers. Consequently, the effect of various parameters on the performance of overlap type separation mechanism can be known and optimal shape and overlap value can be obtained.

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Study on the separation of large ionic-molecules by electrofiltration (전기여과에 의한 거대이온성 분자체 분리현상연구)

  • Park Young-Gyu
    • Journal of the Korean Electrochemical Society
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    • v.1 no.1
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    • pp.18-23
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    • 1998
  • Theoretical model has been derived in the electrophoretic separation system where an electric potential is applied to the system in the axial direction. The effect of electrophoretic convection in the polymeric media is significantly contributed to separate large ionic-molecules because the conformation of large ionic-molecule quickly orients in the field direction. The dependence of the transport in the polymeric media upon field intensity and molecular size aids in understanding the transport of large ionic-molecule in the system, since the convective velocity of large ionic-molecule is accelerated inside a porous material. The separation of two different large ionic-molecules is predicted with a value of $(Pe_t/Pe_g)$ of individual large ionic-molecule using an operator and the reptation theories.