• Title/Summary/Keyword: 여과지

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A Study on the Effect of Rare Earth Screen Filter (희토류 증감지를 이용한 여과판의 효과)

  • Huh, Joon;Kim, Chang-Kyun;Lee, In-Ja;Shin, Wha-Soo;Park, Jun-Chul;Kang, Hong-Seok;Ahn, Bong-Seon
    • Journal of radiological science and technology
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    • v.11 no.1
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    • pp.17-23
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    • 1988
  • As the reutilizing method of exhausted screen, authors used it as a filter and compared with the aluminium filtration. The results are as followed; 1. One sheet of gadolinium front screen has the same radiation absorption as $2.8{\sim}3.3\;mm$ Al equivalent and regular tungsten screen $2.3{\sim}2.7mm$ Al. 2. HVL after Gd-screen filtration was less than the values after aluminium and tungsten-screen filtration. And, image definition with Gd-screen filtration was better than other two cases. Ana surface dose to produce a same film density was more than other two cases. It will be very useful to apply, Gd-screen filter in clinics as it has no deficiency of image quality.

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The Analysis of Coagulation Effect in the Water Treatment Plant by Input of Micro-Particles having Different Specific Gravity (비중이 다른 미세입자의 투입에 따른 정수장의 응집 효과 분석)

  • Kwon, Young-Bin;Choi, Gye-Woon;Lee, Joo-Kyoung;Park, Hyo-Seon
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.673-677
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    • 2009
  • 현재 상수시설의 경우 갈수록 악화되는 수질과 정수장의 유지관리 인원 상주의 어려움, 기존의 응집, 침전, 여과 정수처리 시스템의 처리성능 증대에 따른 한계성에 직면한 상황이다. 안정적으로 수질의 개선을 통한 장치의 컴팩트화, 유지관리가 편리한 고도정수 수질기준에 만족하는 정수처리 시스템이 필요하다. 본 연구에서는 기존의 정수처리 시설인 혼화지에 응집제와 함께 다양한 비중을 가지고 있는 모래입자를 투입하여 응집제와 모래의 결합에 따른 탁도 제거효율과 슬러지의 양을 비교하였으며, 침전지내에 정류벽을 설치하여 침전지 초반에 가라앉을 수 있도록 유도하여 탁도 및 슬러지양을 비교하였다. 응집제만 투입한 경우보다 시료를 투입한 경우가 탁도제거율과 슬러지양이 상승하는 것을 볼 수 있으며 그중에서도 규사의 경우가 가장 많은 탁도제거율의 상승을 나타냈다. 또한 이중 정류벽을 설치하여 탁도 및 슬러지양을 측정한 결과 이중정류벽을 설치하지 않은 경우보다 탁도제거율 및 슬러지양 또한 높게 측정되었으며 슬러지의 양 또한 침전지 앞부분에 집중되는 것으로 나타났다. 이러한 경우 상기 플럭의 질량이 증가하기 때문에 처리속도를 높이고, 체류시간을 줄이고, 처리를 효율적으로 안정되게 수행하는 것이 가능하다. 본 연구결과를 바탕으로 정수시설의 설치에 있어 시료와 이중정류벽을 함께 사용할 경우 응집제의 절감 또는 침전지의 컴팩트화를 가져올 것으로 예상된다.

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Enzymatic Radioiodination of Insulin for Radioimmunoassay Use

  • Awh, Ok-Doo;Kim, Jae-Rok
    • Nuclear Engineering and Technology
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    • v.12 no.2
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    • pp.81-87
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    • 1980
  • Insulin was labelled with $^{125}$ I using lactoperoxidase as an oxidizing agent. The reaction product was purified via two stages: a starch gel electrophoresis(SGE) and a Sephadex gel filtration (SF). Upon comparison of the labelling yields and the bindabilities of the labelled insulin to its antibody, it has been found that the enzyme method shows higher yields (50%) and the better bindability to its antibody than the conventional chloramine-T method (35%). By checking the insulin blank labelling mixture with a SGE, a paper chromatography, and a radioautography technique, a by-product in the lactoperoxidase method has been identified. The separated fractions in SGE and SF were also analyzed and discussed.

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Drug-resistant bacteria isolated from Nakdong river and Carp-ponds (낙동강 잉어와 양식잉어의 장내약제내성균)

  • CHUN Seh Kyu;PARK Sung Woo;JUNG Young Sook
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.16 no.1
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    • pp.17-24
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    • 1983
  • The intestinal drug-resistant bacteria of carps in three recirculating system ponds in Pusan from May to September 1981 were isolated. Both fishes and waters, sampled from the fish farm in National Fisheries University of Pusan and Nakdong River, were tested in 1982. As results of both experiments, although frequent occurrence of drug-resistant bacteria was low in comparison with the foreign countries, it showed incresing tendency in this experiments, and level of the drug-resistant tolerance was incresing gradually. To decrease drug-resistant bacteria of culturing waters and fishes in our country, it is nessesary that, we should diagnose diseases actually and cure them with a right prescription and dosage. .At the end, it is the best way not to abuse drugs fundamentally.

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Application of vegetative filter strip to control nonpoint source pollution (비점원 오염관리를 위한 식생여과대의 적용)

  • Chung, Ji-Eun;Chung, Sang-Ok
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2002.10a
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    • pp.417-420
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    • 2002
  • Non-point source pollution of sediment, plant nutrients and pesticides from cropland has been identified as a significant environmental problem. Vegetative Filter Strips have been identified as one of BMPs to control nonpoint source pollution. This paper reviews the concept, functions, design criteria and management of VFS to control nonpoint source pollution.

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An Improvement of Partition-Based Spatial Merge Join using Dynamic Object Decomposition (동적 객체 분해를 이용한 분할 기반의 공간 합병 조인의 개선)

  • Choi, Yong-Jin;Lee, Yong-Ju;Park, Ho-Hyun;Lee, Sung-Jin;Chung, Chin-Wan
    • Journal of KIISE:Databases
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    • v.27 no.2
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    • pp.247-255
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    • 2000
  • Traditional object decomposition techniques do not decompose spatial objects dynamically during spatial joins, because the object decomposition is very expensive. In this paper, we propose a modified object decomposition technique that can be applied in PBSM(Partition Based Spatial Merge-Join). In real-life data, there are much differences among the sizes of objects. We decompose only large objects with great effects on spatial joins. This technique decreases the decomposition cost of objects during spatial joins and enables efficient filter-refinement steps. Experiments show that the PBSM used with our proposed method performs significantly better than the traditional PBSM.

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A New Multicasting Method in a Multiple Access Network (다중 접근 네트워크에서의 새로운 멀티캐스트 기법)

  • 정민규;김용민;김종권
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.19 no.9
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    • pp.1824-1837
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    • 1994
  • Broadband ISDN will support advanced communication services such as multimedia conference, VOD and electronic news service. Because many of these advanced services require multimedia data delivery, future communication networks must have flexible and efficient multiparty communications capabilities. In this paper we propose a new multicasting method which uses packer filtering capabilities both in a physical network and in a logical network layers. This new scheme has potential to reduce the transmission and packet processing overheads of multicast communications. For the new multicasting method, we develop a group matching algorithm which finds a suitable set of groups that covers multiple target hosts. We show the application of the multicasting method and the group matching algorithm with two simple examoles.

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Fabrication of an IrDA transceiver module for wireless infrared communication system OPR 1002 (850nm 적외선을 이용한 근거리 무선통신 시스템용 송수신 모듈 제작)

  • 김근주
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.1B
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    • pp.175-182
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    • 2000
  • (A hybrid-type wireless infrared data communication module was fabricated by using the light emitting andabsorption diodes with the one-chip of integrated digital circuits. The light emitting diode with the peak spectrum of 850 nm was made from compound semiconductor material of AIGaAs and shows high speed signal transmission with the delay time of 60 nsec for the light direction angle of 30". The Si PIN photodiode showsthe good absorption rate for the range of wavelength of 450-1050 nm and convex-type epoxy lens was utilized for the spectrum filtering on the visible-range spectrum below 750 nm, The data transmission speed is 115.2 kbps and the fabricated module satisfies on the IrDA 1.0 SIR standard requirements.)ments.)

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Spam-mail Filtering based on Lexical Information and Thesaurus (어휘정보와 시소러스에 기반한 스팸메일 필터링)

  • Kang Shin-Jae;Kim Jong-Wan
    • Journal of Korea Society of Industrial Information Systems
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    • v.11 no.1
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    • pp.13-20
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    • 2006
  • In this paper, we constructed a spam-mail filtering system based on the lexical and conceptual information. There are two kinds of information that can distinguish the spam mail from the legitimate mil. The definite information is the mail sender's information, URL, a certain spam keyword list, and the less definite information is the word lists and concept codes extracted from the mail body. We first classified the spam mail by using the definite information, and then used the less definite information. We used the lexical information and concept codes contained in the email body for SVM learning. According to our results the spam precision was increased if more lexical information was used as features, and the spam recall was increased when the concept codes were included in features as well.

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Theoretical analysis of the projection of filtered data onto the quantization constraint set (양자화 제약 집합에 여과된 데이터를 투영하는 기법의 이론적 고찰)

  • 김동식;박섭형
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.7
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    • pp.1685-1695
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    • 1996
  • The postprocessing of compressed images based on the projections onto convex sets and the constrained minimization imposes several constraints on the procesed data. The quantization constraint has been commonly used in various algorithms. Quantization is many-to-one mapping, by which all the dat in a quantization region are mapped to the corresponding representative level. The basic idea behind the projection onto the QCS(quantization constraint set) is to prevent the processed data from diverging from the original quantization region in order to redue the artifacts caused by filtering in postprocessing. However, there have been few efforts to analye the POQCS(projection onto the QCS). This paper analyzed mathematically the POQCS of filtered data from the viewpoint of minimizing the mean square error. Our analysis shows that a proper filtering technique followed by the POQCS can reduce the quantization distortion. In the conventional POQCS, the outside data of each quantization region are mapped into the corresponding boundary. Our analysis also shows that mappingthe outside data to the boundary of a subregion of the quantization region yields lower distortion than does the mapping to the boundary of the original region. In addition, several examples and discussions on the theory are introduced.

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