• Title/Summary/Keyword: 여과지

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Preparation and Treatment of Sulfur Dioxide Gas Generating Agent for Storage of Grape Fruits (포도 저장을 위한 아황산가스 발생제의 제조 및 처리 방법)

  • Choi, Seong-Jin
    • Food Science and Preservation
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    • v.15 no.6
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    • pp.791-795
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    • 2008
  • In order to establish the method to prepare and use the sulfur dioxide gas generating agent in low temperature storage of grape fruits, the $SO_2$ generation capacity from various sulfite compounds was investigated, and the method to regulate $SO_2$ gas generation and to detect the gas was developed. The conidial germination and mycelium growth of Botrytis cinerea which causes gray mold disease during grape fruit storage was completely inhibited at the $SO_2$ gas concentration of 400 ppm and 3200 ppm, respectively. Sodium hydrosulfite generated the most amount of $SO_2$ gas among the investigated 5 different sulfite or bisulfite compounds. By adjusting the number of pinholes on packaging film of the compound or by adding pH adjusting agent, e.g. citric acid or phosphates, it was possible to regulate the amount and duration of $SO_2$ gas generation from the compound. Because malachite green was quantitatively discolored by $SO_2$ gas, the solution or impregnated paper with the compound could be practically utilized as a indicator detecting $SO_2$ gas. Finally, when Muscat Bailey A grape was stored at low temperature with $SO_2$ gas generating agent, the disease incidence was reduced after storage.

Defeating IP Source Address Spoofing with Foreign Agent Care-of-Address in Mobile IPv4 (Mobile IPv4 네트워크에서 접속제어리스트와 역터널링을 이용한 IP Spoofing 제거 방안)

  • Kim, Han-Lim;Kim, Sung-Il;Kim, Sang-Eun;Park, Se-Jun
    • 한국정보통신설비학회:학술대회논문집
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    • 2005.08a
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    • pp.313-317
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    • 2005
  • The network ingress filtering is a simple and efficient method for preventing IP source spoofing of fixed nodes. Since mobile hosts cannot communicate with its correspondent nodes if the network ingress filtering is configured in mobile IPv4 network, reverse tunneling was considered as a method for avoiding network ingress filtering. But, unfortunately this method does not solve IP source spoofing of mobile nodes. In this paper, we propose a simple and efficient method for preventing IP source spoofing of mobile nodes assuming that only the mobile hosts connected to foreign agents and the network that foreign agent manages is small.

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Manufacture of High Purity KI Crystal by Fractional Crystallization Method from Aqueous Waste of KI (KI 폐용액(廢溶液)으로부터 분별결정법(分別結晶法)에 의한 고순도(高純度) KI결정(結晶) 제조(製造)에 관한 연구(硏究))

  • Kim, Dae Weon;Jang, Seong Tae;Choi, Sung Bum
    • Resources Recycling
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    • v.22 no.1
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    • pp.48-54
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    • 2013
  • A laboratory study was carried out to recover KI crystals with high purity by using fractional crystallization method from a waste solution generated from the production of polarizing film for LCD industry. The waste solution contains 1.3% KI, and other impurities such as B, Na, and PVA etc. With purity higher than 99.5% KI crystals were produced through refining process such as vacuum evaporation, fractional crystallization, filtering, and 24hr aging. Also the concentrated impurities were eliminated about 70% by recrystallization.

Parallel Processing of Multi-Way Spatial Join (다중 공간 조인의 병렬 처리)

  • Ryu, Woo-Seok;Hong, Bong-Hee
    • Journal of KIISE:Databases
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    • v.27 no.2
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    • pp.256-268
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    • 2000
  • Multi-way spatial join is a nested expression of two or more spatial joins. It costs much to process multi-way spatial join, but there have not still reported the scheme of parallel processing of multi-way spatial join. In this paper, parallel processing of multi-way spatial join consists of parallel multi-way spatial filter and parallel spatial refinement. Parallel spatial refinement is executed by the following two steps. The first is the generation of a graph used for reducing duplication of both spatial objects and spatial operations from pairs candidate object table that are the results of multi-way spatial filter. The second is the parallel spatial refinement using that graph. Refinement using the graph is proved to be more efficient than the others. In task creation for parallel refinement, minimum duplication partitioning of the Spatial_Obicct_On_Node graph shows best performance.

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Case-based Filtering by Using Degree of Membership for Digital Contents (디지털 콘텐츠를 위한 소속도를 이용한 사례기반 필터링)

  • Kim, Hyung-Il
    • The Journal of the Korea Contents Association
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    • v.10 no.10
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    • pp.9-18
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    • 2010
  • As digital contents become vast in quantity, it takes long time for users to search the digital contents they want, which is a problem that has arisen. Therefore, it is required to have the technology that analyzes vast digital contents and extracts the appropriate contents for users in order to provide them with contents they want. For a fast searching of digital contents suitable for users, it is necessary to have the technology of filtering for digital contents. In this paper, we propose a method of filtering digital contents suitable for individual users. The method suggested in this paper is to analyze case-based information in digital contents and provide the digital contents suitable for individual users. The case for using digital contents is used for analysis of users' preference. Various simulations were conducted to confirm the effectiveness of the proposed method.

Numerical Analysis of the Turbulent Flow through an Oil-Grit Separator according to Turbulent Models (난류모형에 따른 유류 유사분리기내에서의 유류-흐름해석)

  • Lee, Jin-Woo;Yoo, Je-Seon;Cho, Yong-Sik
    • Proceedings of the Korea Water Resources Association Conference
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    • 2008.05a
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    • pp.1761-1764
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    • 2008
  • 본 연구에서는 상용 3차원 수치모형 코드인 FLOW-3D를 이용하여 난류모형에 따른 유류-유사 분리기 내에서 유체의 흐름거동을 해석하였다. 우수로 인해 발생한 유출수는 유류, 유사 및 쓰레기 등을 포함하고 있기 때문에 3차원적 거동을 하고 다양한 흐름특성을 갖는다. 유류-유사 분리기는 도심지의 지하구조물로서 이러한 유출수의 수질을 개선하여 하천이나 강으로 흘려보내는 기능을 갖는다. 분리기내에서의 복잡한 흐름 거동을 해석하기위해 정류판과 유류흡착기로 구성된 유류-유사분리기를 제작하여 수치모의를 실시하였다. 유류-유사분리기로 유입되는 유입수에 포함된 유사는 유체의 흐름이 분리기내에 설치되어있는 정류판을 지나면서 여과되도록 하였고 유사와 함께 유입수에 포함된 유류는 유류흡착기를 통해 여과되도록 하였다. 기존의 수리실험 결과와 수치모의를 통한 연구결과에서 유입수에 포함된 유사와 유류는 유류흡착기를 설치하였을 경우 유사와 유류의 분류활동이 더 활발하게 이루어지는 것을 알 수 있었다. 따라서, 본 연구에서는 유사와 유류의 포획률을 증가시키기 위한 단계로서 유류-유사분리기에 유류흡착기를 설치하고 분리기내의 복잡한 흐름을 각각의 난류모형을 이용하여 비교분석하였다. 수치모의는 $\kappa$ - 모형과 LES(Large Eddy Simulation) 모형의 두가지 난류모형을 사용하였고, FLOW-3D를 이용하여 3차원 수치모의를 실시하였다.

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A Compromise-Resilient Tunneled Packet Filtering Method in Wireless Sensor Networks (무선 센서 네트워크에서 훼손 감내하는 터널된 패킷 여과 기법)

  • Kim, Hyung-Jong
    • Convergence Security Journal
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    • v.8 no.1
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    • pp.19-26
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    • 2008
  • In wireless sensor networks, an adversary can launch the wormhole attacks, where a malicious node captures packets at one location and tunnels them to a colluding node, which retransmits them locally. The wormhole attacks are very dangerous against routing protocols since she might launch these attacks during neighbor discovery phase. A strategic placement of a wormhole can result in a significant breakdown in communication across the network. This paper presents a compromise-resilient tunneled packet filtering method for sensor networks. The proposed method can detect a tunneled message with hop count alteration by a comparison between the hop count of the message and one of the encrypted hop counts attached in the message. Since the proposed method limits the amount of security information assigned to each node, the impact of wormhole attacks using compromised nodes can be reduced.

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Production of Artificial Seeds by Alginate-encapsulation of Rice Somatic Embryos (벼의 수화겔 인공종자 생산)

  • 정원중;민성란;송남희;유장렬
    • Korean Journal of Plant Tissue Culture
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    • v.21 no.3
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    • pp.183-186
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    • 1994
  • Somatic embryos derived from cell suspension cultures of rice were singly alginate-encapsulated to be used as artificial seeds. When placed on half strength MS solid medium,73% of the encapsulated somatic embryos were capable of germination Encapsulation per se did not affect the germination frequency of embryos. When incubated by wrapping with moistured non-sterile filter paper, 60% of the encapsulated somatic embryos germinated. However encapsulated zygotic embryos without endosperm showed a high germination frequency regardless of the sterility of the incubation conditions. The results suggest that a greater susceptibility of somatic embryos to contaminants is attributed to lower germination frequency of encapsulated somatic embryos in non-sterile conditions.

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The adaptive filter configuration for down stream of Naktong river (낙동강 하류원수에 적합한 여과지의 여재구성)

  • Kim, Sang-goo;Ryou, Dong-choon;Lee, Yung-sik;Son, Jin-eun
    • Journal of Environmental Science International
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    • v.4 no.5
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    • pp.95-95
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    • 1995
  • This study was carried out to evaluate the variations of headloss rate and of specific deposit to depths with effective size of media and configuration of filter layer during algae blooming period. 0.51mm size media was disqualified because most of headloss occurred rapidly below 5cm from surface layer however 0.91mm size media acted deep filtration more than 20cm from top, as result 0.91mm sixte media filter had 2∼3 times longer filtration time than 0.51mm sixte media filter, but 0.91mm size media have break-through potentiality. multi-layer filter with 1.02mm anthracite and 0.51mm sand had large deposit volume in upper layer that could longer filtration time, moreover smaller media in lower layer that could protect break-through.

Numerical Analysis of the Turbulent Flow through an Oil-Grit Separator (3차원 모형을 이용한 유류-유사분리기내에서의 난류흐름해석)

  • Lee, Jin-Woo;Lee, Seung-Oh;NamGung, Don;Cho, Yong-Sik
    • Proceedings of the Korea Water Resources Association Conference
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    • 2007.05a
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    • pp.1254-1257
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    • 2007
  • 본 연구에서는 유류-유사 분리기내에서 유체의 흐름거동을 상용 3차원 수치모형인 FLOW-3D를 이용하여 해석하였다. 유류-유사 분리기는 도심지의 우수로 인한 유출발생시 동반되는 이물질을 여과시키는 기능을 가진 지하구조물이다. 우수로 인한 유출이 발생하여 유류-유사 분리기내로 흘러들어오는 유입수는 3차원적 거동을 하고 다양한 흐름특성을 갖는다. 따라서, 분리기내에서의 흐름거동을 정확히 해석하는데 많은 어려움이 있다. 본 연구에서는 정류판(baffle)과 유류흡착기(oil skimmer)로 구성된 유류-유사 분리기에서의 유류와 유사를 포함하고 있는 유출수의 복잡한 거동을 해석하기 위해 수치모의를 실시하였다. 유류와 유사에 대한 포착률(oil and grit trap)은 유류-유사 분리기내에서 유체의 흐름거동과 관계된다. 따라서, 본 연구에서는 유류와 유사의 포착률을 향상시키기 위한 수치모의의 기초적인 단계로서 유류-유사 분리기내에서 유류흡착기(oil skimmer)를 설치한 경우와 설치하지 않은 경우에 대한 유체의 흐름거동을 FLOW-3D를 이용하여 3차원 수치모의를 실시하였다. 수치모의를 통해 유류흡착기의 유무에 따른 유류-유사 분리기내에서의 흐름거동을 알 수 있었으며, 유류흡착기를 설치한 경우엔 유류 흡착기에 의해 여과될 수 있는 유류와 유사에 대한 각각의 포획률이 높아짐을 알 수 있었다.

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