• 제목/요약/키워드: The rapid leakage

검색결과 225건 처리시간 0.028초

The safety behavior of agricultural reservoirs due to raising the embankment

  • Lee, Dalwon;Lee, Younghak
    • 농업과학연구
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    • 제40권3호
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    • pp.243-252
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    • 2013
  • This study was carried out to investigate safety evaluation of agricultural reservoirs due to raising the embankment. The seepage analysis and large-scale model test were performed to compare and analyze the pore water pressure(PWP), leakage quantity, settlement and piping phenomenon in the inclined core type and the vertical core type embankments. The PWP after raising the embankment showed smaller than before raising the embankment and the stability for piping after raising the embankment. The allowable seepage quantity and the allowable leakage for the steady state and transient conditions is within the range of safe management standard. After raising the embankment in the inclined core, there was no infiltration by leakage. For the vertical core, the PWP showed a large change by faster infiltration of pore water than in the inclined core. In a rapid drawdown, inclined core was remained stable but the vertical core showed a large change in PWP. Settlement after raising the embankment showed larger amounts of settlement than before raising the embankment. The leakage quantity before raising the embankment and the inclined core type showed no leakage. From the result, an instrument system that can accurately estimate a change of PWP shall be established for the rational maintenance and stabilization of raising the embankment for agricultural reservoirs.

해저터널 급속차폐시스템의 Inflater 분할구조에 따른 터널 내 차수효율에 대한 실험적 연구 (Model testing of leakage effect due to multi-cell inflater of rapid protection system in subsea tunnel)

  • 유광산;이지현;김연덕;김상환
    • 한국터널지하공간학회 논문집
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    • 제17권3호
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    • pp.295-303
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    • 2015
  • 본 논문은 해저터널 시공 및 운영 시 발생되는 돌발용수 및 이상누수에 의한 사고에 대비하기 위한 해저터널 급속차폐시스템의 Inflater 분할구조에 따른 터널 내 차수효율에 대한 실험적 연구이다. 해저터널 특성상 해수 유입 또는 지하수 유입, 호우로 인한 침수 등 물과 관련된 피해에 대한 방호시스템은 필수적이다. 이 연구에서는 이러한 급속차폐를 위해 고안된 Inflater 구조에 대하여 형태 및 분할에 따른 차폐능력, 누수량, 수압 그리고 축방향 변위 등을 연구하기 위하여 27:1 축소율을 적용한 실내모형을 다양한 Inflater 분할구조별로 실시하였다. 연구결과에 의하면 2분할 Inflater 구조인 경우가 다른 분할에 비해 시간당 누수량 및 축방향 변위가 낮아 차폐능력이 좋은 것으로 나타났다. 이러한 결과는 해저터널의 제원에 따라 다소 차이는 있을 것으로 예측되나 기본적으로 차폐시스템 설계 및 개발기술 발전에 매우 유용하게 활용될 것으로 기대된다.

축류 팬 누설 와류의 난류 특성 (Turbulence Characteristics of a Leakage Vortex in an Axial-Flow Fan)

  • 명환주;백제현;류호선;이인섭
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 1999년도 유체기계 연구개발 발표회 논문집
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    • pp.227-233
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    • 1999
  • Detailed Measurements were made to investigate the turbulence characteristics of a leakage vortex in an axial-flow fan using three-dimensional LDV. The turbulence in the leakage vortex has highly anisotropic characteristics with the radial value being the maximum. The turbulence intensity components in the vortex in the streamwise and tangential directions increase up to a certain downstrean position and then decrease. This increase is mainly due to the rapid decrease of the streamwise velocity of the vortex and partly due to the radial gradient of the streamwise velocity caused by a velocity deficit. As the vortex decays moving downstream, turbulence intensity also decrease gradually.

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Effect of Annealing on the Dielectric Properties and Microstructures of Thin Tantalum Oxide Film Deposited with RF Reactive Sputtering

  • 이경수;남기수;천창환;김근홍
    • ETRI Journal
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    • 제13권2호
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    • pp.21-27
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    • 1991
  • Effects of annealing on the dielectric properties and microstructures of thin tantalum oxide film(25nm) deposited on p-type Si substrate with rf reactive magnetron sputtering were investigated. The leakage current density was remarkably reduced from $10^-8$ to $10^-12$ A/$\mum^2$at the electric field of 2MV/cm after rapid thermal annealing(RTA) in $O_2$at $1000^{\circ}C$, while little leakage reduction was observed after furnace annealing in $O_2$ at $500^{\circ}C$. The structural changes of thin tantalum oxide film after annealing were examined using high resolution electron microscope(HREM). The results of HREM show that substantial reduction in the leakage current density after the RTA in $O_2$ can be attributed to crystallization and reoxidation of the thin amorphous tantalum oxide film.

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RTMOCVD법에 의해 제조된 Ta2O5 박막의 특성 (Characteristics of Ta2O5 thin film prepared by RTMOCVD)

  • 소명기
    • 산업기술연구
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    • 제19권
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    • pp.101-105
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    • 1999
  • Ultra thin $Ta_2O_5$ gate dielectrics were prepared by RTMOCVD (rapid thermal metal organic chemical vapor deposition) using Ta source $TaC_{12}H_{30}O_5N$ and $O_2$ gaseous mixtures. As a result, $Ta_2O_5$ thin films showed significantly low leakage current compared to $SiO_2$ of identical thickness, which was due to the stabilization of the interfacial layer by NO ($SiO_xN_y$) passivation layer. The conduction of leakage current in $Ta_2O_5$ thin films was described by the hopping mechanism of Poole-Frenkel (PF) type.

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지식가치를 극대화하기 위한 다큐먼트 보안 디자인 (Design of document security to maximize knowledge value)

  • 장덕성
    • 한국디지털정책학회:학술대회논문집
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    • 한국디지털정책학회 2003년도 창립학술대회
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    • pp.161-170
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    • 2003
  • Knowledge management system building knowledge acquisition, knowledge share, and knowledge maintenance for the member of corporation is expanded throughout whole industry to cope with rapid business environment. Electronic document basing knowledge management system can copy, print, and transfer knowledge to another party, so it is being regarded as a essential infrastructure to share knowledge. However, considering most of information leakage is sprung up by insider of organization, it is considered to provide countermeasure to protect illegal use from information leakage. The purpose of this paper is to establish digital information security system through design of document and manage digital information assets safely through electronic document security system protecting illegal leakage of digital information assets.

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BST 박막의 비대칭전극재료에 따른 누설전류특성 (The Leakage Current Properties of BST thin films with Unsymmetrical Electrode Materials)

  • 전장배;김덕규;박영순;박춘배
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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    • pp.329-332
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    • 1999
  • In this paper, BST((Bao.&o,dTi0:3) thin films were deposited by the rf magnetron sputtering method on Pt/$SiO_2$/Si substrate. Pt, $RuO_2$, Ag, Cu films for the formation of top electrode were deposited on BST thm films. And then Top Electrodes/BST/Pt capacitors were annealed with rapid thermal annealing(RTA) at various temperature. We have investigated effect of post-annealing on the electrical properties such as dielectric constant and leakage current of the capacitors. It was found that electrical properties of the capacitors were greatly depended on the annealing temperatures as well as the materials of top electrodes. In BST thin films with Pt top electrode was annealed at $700^{\circ}C$. the dielectric constant was measured to the value of 346 at l[kHzl and the leakage current was obtained to the value of $8.76\times10^8$[A/$\textrm{cm}^2$] at the forward bias of 2[V].

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직류전기철도 전식대책 실증실험(2) 속응형 정전위 정류기 (Field Test of Mitigation Methods for Stray Currents from DC Electric Railroad(2) Rapid Potential-Controlled Rectifier)

  • 하윤철;하태현;배정효;이현구;김대경;최정희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.217-219
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    • 2007
  • With the wide spread of direct current(DC) electric railroads in Korea, the stray current or leakage currents from negative return rails become a pending problem to the safety of nearby underground Infrastructures. The most widely used mitigation method for this interference is the stray current drainage method, which connects the underground metallic structures to the rails with diodes (polarized drainage) or thyristor (forced drainage). This method, however, inherently possesses some drawbacks such as an increase of total leakage torrents from rails, expansion of interference zone, etc. In order to resolve these drawbacks, we developed a rapid potential-controled rectifier and applied to a depot area where stray current inference is very severe. The effect of this method was analyzed from the field tell data and we suggest this method can be an excellent alternative to the drainage-bond-based mitigation methods.

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급속열처리에 의한 TiN/$TiSi_2$ 이중구조막을 이용한 submicron contact에서의 전기적 특성 (The Electrical Roperties of TiN/$TiSi_2$ Bilayer Formed by Rapid Thermal Anneal at Submicron Contact)

  • 이철진;성만영;성영권
    • 전자공학회논문지A
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    • 제31A권9호
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    • pp.78-88
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    • 1994
  • The electrical properties of TiM/TiSi$_{2}$ bilayer formed by rapid thermal anneal in NH$_{3}$ ambient after the Ti film is deposited on silicon cubstrate are investigated. N$^{+}$ contact resistance slightly increases with increasing annealing temperature with P$^{+}$ contact resistance decreases. The contact resistance of N$^{+}$ contance was less than 24[.OMEGA.] but P$^{+}$ thatn that of N$^{+}$ contact but the leakage current indicates degradation of the contact at high annealing temperature for both N$^{+}$ and contacts. The leakage current of N$^{+}$ Junction was less than 0.06[fA/${\mu}m^{2}$] but P$^{+}$ contact was 0.11-0.15[fA/${\mu}m^{2}$]. The junction breakdown voltage for N$^{+}$ junction remains contant with increasing annealing temperature while P$^{+}$ junction slightly decreases. The Electrical properties of a two step annealing are better than that of one step annealing. The Tin/TiSi$_{2}$ bilayer formed by RTA in NH$_{3}$ ambient reveals good electrical properties to be applicable at ULSI contact.

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그래핀 전극을 이용한 유연한 BMNO (Bi2Mg2/3Nb4/3O7) 캐패시터의 굽힘 특성 (Bending Properties of the Flexible BMNO (Bi2Mg2/3Nb4/3O7) Capacitor Using Graphene Electrode)

  • 송현아;박병주;윤순길
    • 한국전기전자재료학회논문지
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    • 제25권5호
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    • pp.387-391
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    • 2012
  • Graphene was fabricated onto Ni/Si substrate using a rapid-thermal pulse CVD and they were transferred onto the Ti/PES flexible substrate. For top electrode applications of the BMNO dielectric films, graphene was patterned using a argon plasma. Through an AFM image and a leakage current density of the BMNO films grown onto various bottom electrodes before and after bending test, BMNO films grown onto the graphene bottom electrode showed no change of the microstructure and the leakage current density after the bend.