• Title/Summary/Keyword: protection layer

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Soil Column Experiment to Evaluate Removal of Nutrients in Stormwater Runoff by Soil of Riparian Protection Zone (토양칼럼을 이용한 초기우수 중 염양염류의 수변녹지 토양에서의 제거도 평가)

  • Yoon, Seok-Pyo;Choi, Ji-Yong
    • Journal of Korean Society on Water Environment
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    • v.20 no.3
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    • pp.231-235
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    • 2004
  • To investigate removal effects of nutrients in stormwater runoff by soil of riparian protection zone, soil column experiment was conducted for 20 months. Artificial stormwater runoff containing phosphate and nitrate was applied on the surface of soil column twice a week, and phosphate and nitrate concentrations were measured from the leached water. Soil of riparian protection zone reduced the released amount of infiltrated water to the surrounding water. After infiltration of 1m depth of soil column, average removal rates of phosphate and nitrate were 97.7 % and 74.7 %, respectively. As main mechanisms of phosphate are adsorption to soil particle and utilization by plants, periodical replacement of soil and harvesting of plant at the end of growing season are required. For the removal of nutrients in stormwater runoff by the soil layer, soil of riparian protection zone has higher hydraulic conductivity to infiltrate stormwater. Sandy soil having hydraulic conductivity of about $1{\times}10^{-2}cm/s$ range might be appropriate for this purpose.

Experimental Study on Hydraulic Characteristics of Wave Dissipating Modified- Tribar (Modified- Tribar의 수리특성에 관한 실험적 연구)

  • KIM IN-CHUL;PARK YOUNG-WOO;KWEON HYUCK-MIN
    • Journal of Ocean Engineering and Technology
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    • v.18 no.4 s.59
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    • pp.23-32
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    • 2004
  • Specially shaped concrete blocks are used for the armor layer of rubble structure for breakers, seawalls, or other shore protection work. In this study, the hydraulic characteristics of the Modified-Tribar(MTB), which addresses the shortcomings of the Arch-Tribar, and the most widely used Tetrapod(TTP) in Korea are examined through hydraulic model tests. The MTB are much more stable than the TTP, as shown through the stability model tests under non-breaking and non-overtopping condition. The value of the stability coefficient(KD) was obtained at around 30. The model tests show that the TTP random two layers and MTB uniform 1.5 layers have similar effects, but the MTB one layer shows slightly low effects in dissipating wave energy. The TTP random two layer model is the most effective in reducing wave overtopping rate, under overtopping condition, while the MTB uniform one layer and the MTB uniform 1.5 layer models follow respectively.

Routing and Wavelength Assignment in Survivable WDM Networks (생존도를 고려한 WDM 망의 경로설정 및 파장할당)

  • Lee, Taehan;Park, Sungsoo
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2001.10a
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    • pp.124-127
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    • 2001
  • We consider the routing and wavelength assignment problem in survivable WDM transport network without wavelength conversion. We assume the single-link failure and a path protection scheme in optical layer. When a physical network and a set of working paths are given, the problem is to select a link-disjoint protection path for each working path and assign a wavelength for each working and protection path. We give an integer programming formulation of the problem and propose an algorithm to solve it based on column generation technique and variable fixing. We devise a branch-and-price algorithm to solve the column generation problem. We test the proposed algorithm on some randomly generated data and test results show that the algorithm gives very good solutions.

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Study on Museum Digital Exhibition Mode and Industrialization of Intangible Cultural Heritage

  • Bai, Jian-Song;Boo, Jong-Chul
    • Journal of information and communication convergence engineering
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    • v.9 no.2
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    • pp.129-134
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    • 2011
  • Nowadays, most of exhibits are material antiquities while the exhibit of intangible cultural heritage is deficient and the form is less advanced which cannot meet the exhibition needs of digital times. This has resulted in insufficient display of intangible heritage's value which may not facilitate inherit and protection of intangible heritage, no other than protection mechanism of forming healthy industrialization. This article has established digital exhibition mode in museum about intangible cultural heritage by analysis on current museum and using mobile communication and augmented reality techniques. Discuss the mode in the layer integrating creative industry and mobile industry and provide practicable reference project of forming the healthy industrialization mechanism for protecting intangible heritage.

An Improvement of Distance Relay Technique Reliability using Elman Network (Elman Network를 이용한 거리계전기법의 신뢰성 향상)

  • Jung, H.S.;Lee, J.J.;Shin, M.C.;Lee, B.K.;Park, C.W.;Jang, S.I.
    • Proceedings of the KIEE Conference
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    • 2000.07a
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    • pp.212-214
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    • 2000
  • The distance relay technique used for transmission line protection operates overreach and underreach to the self protection region because the power system becomes complex and fault conditions are different. To solve these problems, this paper describes new technique to set the reliable self protection lesion. The trip region of the quadrilateral distance relay is set by training of multi layer recurrent elman network. The proposed network is able to reach the trip zone for the fault impedance, fault initial angle and source impedance variance correctly.

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TLP Properties Evaluation of ESD Protection Device of GGNMOS Type for Conventional CMOS Process (Conventional CMOS 공정을 위한 GGNMOS Type의 ESD 보호소자의 TLP 특성 평가)

  • Lee, Tae-Il;Kim, Hong-Bae
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.21 no.10
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    • pp.875-880
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    • 2008
  • In this paper, we deal with the TLP evaluation results for GGNMOS in ESD protection device of conventional CMOS process. An evaluation parameter for GGNMOS is that repeatability evaluation for reference device($W/L=50\;{\mu}m1.0\;{\mu}m$) and following factors for design as gate width, number of finger, present or not for N+ gurad -ring, space of N-field region to contact and present or not for NLDD layer. The result of repeatability was showed uniformity of lower than 1 %. The result for design factor evaluation was ; 1) gate width leading to increase It2, 2) An increase o( finger number was raised current capability(It2), and 3) present of N+ gurad-ring was more effective than not them for current sink. Finally we suggest the optimized design conditions for GGNMOS in evaluated factor as ESD protection device of conventional CMOS process.

Fracture Mechanism of Ceramic/Glass-fiber-reinforced-composites Laminate by High Velocity Impact (세라믹/유리섬유강화복합재 적층판의 고속충돌에 의한 파괴거동)

  • Jung Woo-Kyun;Lee Woo-Il;Kim Hee-Jae;Kwon Jeong-Won;Ahn Sung-Hoon
    • Journal of the Korean Society for Precision Engineering
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    • v.23 no.5 s.182
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    • pp.170-176
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    • 2006
  • Multi-layered laminate made of ceramic/composite have been developed to prevent penetration by high velocity impact. In this study, three-layered plates consisted of 1) cover layer (glass fiber reinforced polymer), 2) $Al_{2}O_{3}$, ceramic plate, and 3) backing plate (glass fiber reinforced polymer) were fabricated with various conditions and tested for their ballistic protection characteristic. The ceramic composite laminates, with thin backing plate, were completely penetrated by armor piercing projectile. The plate with inserted rubber between ceramic and backing plate showed excellent ballistic protection, though completely penetrated by the second shoot.

Study of the Application of Gel Electrolyte in the Reference Electrode of $Cu/CuSO_4$

  • Lin, Cunguo;Xu, Likun;Liu, Yang
    • Corrosion Science and Technology
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    • v.7 no.3
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    • pp.179-181
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    • 2008
  • With nano-$SiO_2$ and sulphate acid, a kind of colloid electrolyte is synthesized by sol-gel method. It is placed outside the reference electrode as a layer of gel electrolyte so as to decrease the leaching of $Cu^{2+}$ and increase the life of the reference electrode. The performance of the gel electrode in simulating soil solution is measured as follows: the potential of the electrodes ranging from 60 mV to 80 mV (vs. SCE) with potential variation no more than $\pm10mV$, enough resistance to polarization. The $Cu^{2+}$ effusion rate of the reference electrode without gel electrolyte is 3 times that with colloid electrolyte, which means that gel electrolyte can extend the life of the reference electrode significantly.