• Title/Summary/Keyword: Junction Area

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A Study on the Hydraulic Characteristics of River Junctions Using FLDWAV Model (FLDWAV 모형을 이용한 하천합류부에서의 수리학적 특성 연구)

  • Cho, Hyeon-Kyeong
    • Journal of the Korean Society of Industry Convergence
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    • v.10 no.4
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    • pp.275-283
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    • 2007
  • This study aims at the calculation of a variation of flow characteristics of main channel for tributary inflow in river junction. So this study was analyzed the variation of flow depth and velocity in main channel for a change of inflow degree. For this purpose, FLDWAV model are carried out for variations of $30^{\circ}$, $60^{\circ}$ and $90^{\circ}$ tributary inflow at junction. Results show that velocity ratio(V1/V3) increases and flow depth ratio(H1/H3) decreases for discharge ratio(Q1/Q3) of upstream and downstream when degree increases in junction. And FLDWAV model was applied at a real river junctions. Selected area is a junction of Gumho river and Sin stream. Results show that pattern is similar to a virtual channel.

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Numerical Analysis of Waveguide T-Junction (T-접합 도파관의 수치적 해석)

  • Cheon, Changyul;Chung, Jin-Kyo
    • Journal of Industrial Technology
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    • v.13
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    • pp.25-31
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    • 1993
  • This paper presents an analysis of microwave device component. An H-Plane waveguide component with arbitrary shape is analyzed using finite element method(FEM) cooperated with boundary element method(BEM). The finite element method(FEM) is applied to the junction region and the boundary element method(BEM) to the waveguide region. For the application of BEM in the waveguide structure, a ray representation of the waveguide Green's function is used. The proposed technique was applied to the analysis of the waveguide inductive junction to compare the numerical result with the result of the mode matching technique. The comparison showed good agreements between the two results. Transmitted powers were also computed in T-junction waveguides for the various shape of the junction area.

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Junction Capacitance Dependence of Response Time for Magnetic Tunnel Junction (터널링 자기저항 소자의 접합면 정전용량에 따른 전기적 응답특성)

  • Park, S.Y.;Choi, Y.B.;Jo, S.C.
    • Journal of the Korean Magnetics Society
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    • v.12 no.2
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    • pp.68-72
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    • 2002
  • In this research, the effects of capacitance to the access time were studied at the junction area of tunneling magnetoresistance when these were used as memory devices. These results were obtained by applying electric signal input and magnetic field was not used. We applied bipolar square waves of 1MHz to the MTJ samples to obtain the results and time constant ($\tau$) calculated by observing wave responses utilizing an oscilloscope. And time constant was compared with junction area. Each part of MTJ sample, such as electrical pad, lead and contact area, was modeled as an electrical equivalent circuit based on experimental results. For the 200㎛$\times$200㎛ cell, junction capacitance was 90 pF. Also, measurement and simulation results were compared, which showed those similarity.

Back Pain of Muscular Origin (근긴장성 요통의 치료에 대한 새로운 소견)

  • Choi, Joong-Rieb
    • The Korean Journal of Pain
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    • v.6 no.1
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    • pp.83-95
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    • 1993
  • In out-patient clinic, it seems to be common that most back pain arise from muscular origins rather than from skeletal origins. Most physicians have wished to diagnose lower back pain from the radiologic findings only. From clinical experiences and anatomical studies, I have gotten a different opinion from common sense about backaches. If I met a patient who had lower back pain around the posterior superior iliac crest(P.S.I.C.) area, I would had to search a trigger point in the erector spinae muscles at the level of thoraco-lumber junction rather than at the level of the painful site. It is why that sensory innervation over the posterior superior iliac crest area is the posterior primary branch of T12 spinal nerve running down through the erector spinae muscles. Pain on the iliac crest area is supposedly due to hyperirritability of the sensory nerve distributing to this area. Hyperirritability of the posterior primary branch of $T_{12}$ spinal nerve may be due to the spasm of the longissimus thoracis muscle in the erector spinae muscles at the level of the thoraco-lumbar junction. So finally, I would like to insist that spasmolytic treatment on the muscle at the level of the thoraco-lumbar junction would be better for pain relief around P.S.I.C. than treatment at the painful site only.

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Employing Al Etch Stop Layer for Nb-based SNS Josephson Junction Fabrication Process (Al 식각정지층을 이용한 Nb-based SNS 조셉슨 접합의 제조공정)

  • Choi, J.S.;Park, J.H.;Song, W.;Chong, Y.
    • Progress in Superconductivity
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    • v.12 no.2
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    • pp.114-117
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    • 2011
  • We report our efforts on the development of Nb-based non-hysteretic Josephson junction fabrication process for quantu device applications. By adopting and modifying the existing Nb-aluminum oxide tunnel junction process, we develop a process for non-hysteretic Josephson junction circuits using metal-silicide as metallic barrier material. We use sputter deposition of Nb and $MoSi_2$, PECVD deposition of silicon oxide as insulator material, and ICP-RIE for metal and oxide etch. The advantage of the metal-silicide barrier in the Nb junction process is that it can be etched in $SF_6$ RIE together with Nb electrode. In order to define a junction area precisely and uniformly, end-point detection for the RIE process is critical. In this paper, we employed thin Al layer for the etch stop, and optimized the etch condition. We have successfully demonstrated that the etch stop properties of the inserted Al layer give a uniform etch profile and a precise thickness control of the base electrode in Nb trilayer junctions.

A STUDY OF THE ROOT SURFACE AREA, ANATOMIC STRUCTURE AND LINEAR VARIATION OF THE ROOT SURFACE AREA OF THE MANDIBULAR SECOND MOLAR (하악 제2대구치 치근의 형태학적 구조 및 표면적에 관한 연구)

  • Chung, Hyung-Geun;Kwon, Young-Hyuk;Lee, Man-Sup
    • Journal of Periodontal and Implant Science
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    • v.23 no.1
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    • pp.159-169
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    • 1993
  • The thirty six mandibular second molars, which were extracted because of hopeless tooth due to advanced periodontal disease, were measured the length of mesial and distal root and the distance from cementoenamel junction to root separation. The molars were cross-sectioned every 1.5 milimeter from cementoenamel junction to root apex perpendicular to long axis and each section was photographed, projected and measured with a calibrated Digital Curvi-Meter(Com Curvi-8. Japan). The root surface area (RSA), percentage of the RSA and the linear variation of the RSA were calibrated for each 1. 5 mm section. The results were as follows. 1. The mean length of the roots was 12. 98mm for mesial root, 11.84 mm for distal root. The mesial root was longer than distal root.(p<0.01) 2. The mean distance from the cementoenamel junction to the point at which the root separate from the root trunk was 3.82mm for the buccal furcation and 4.75mm for lingual furcation. The buccal root separation was coronal than the lingual root separation.(p<0.01) 3. The total root surface area was $317.78mm^2$. 4. The mean surface area of the root trunk was $150.06mm^2$ and averaged 42.54% of the total root surface area. 5. The mean root surface area was $88.79\;mm^2$ for the mesial root, $78.93mm^2$ for distal root, The mesial root surface area was wider than the distal root surface area.(p<0.05) 6. In comparision, the mean root trunk surface area of the mandibular 2nd molar was wider than that of mandibular 1st molar(p<0.01), but each root of 2nd molar was smaller than that of 1st molar(p<0.01).

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Effect of the size of active device and heatsink of power MOSFETs on its the junction to ambient transient thermal behavior

  • Koh, Jeong-Wook;An, Chul
    • Proceedings of the IEEK Conference
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    • 2000.11b
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    • pp.241-244
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    • 2000
  • To investigate the compact effect of the different area of an active layer and the different type of heatsink on the junction to ambient transient thermal impedance, we have characterized the thermal behavior of power MOSFETs that have three different areas of an active layer and two types of heatsink. To do so, the "cooling curve method" has been used in order to measure the junction-to-ambient transient thermal impedance Zthja that represents the thermal behavior of the devices. The measured data depiets that the larger area of an active layer gives the better-in other words. smaller-thermal impedance, and that the larger size of a heatsink improves the thermal impedance.

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Characteristics of Air Pollution at a Junction Area Contaminated with Vehicle Emissions (자동차 배출가스에 의한 도심 교차로의 대기오염 특징)

  • Lee, Seung-Bok;Bae, Gwi-Nam
    • Transactions of the Korean Society of Automotive Engineers
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    • v.18 no.4
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    • pp.48-53
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    • 2010
  • Roadside measurement of ultrafine particles, black carbon, and NOx was carried out to investigate air pollution at a junction area contaminated with vehicle emissions in Seoul from March 19 to 23, 2007. Diurnal variation of ultrafine particles, black carbon, and $NO_x$ concentrations at a roadside showed minimum at around 2-4 a.m. and two peak modes during the morning and evening rush hours. Since these pollutants might be mainly emitted from vehicles, the roadside was highly contaminated with vehicles.

Junction Area Dependence of Tunneling Magnetoresistance in Spin-dependent Tunneling Junction with Natural $Al_2O_3$Barrier (자연산화 $Al_2O_3$장벽층을 갖는 스핀의존 터널링 접합에서 자기저항특성의 접합면적 의존성)

  • 이긍원;이상석
    • Journal of the Korean Magnetics Society
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    • v.11 no.5
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    • pp.202-210
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    • 2001
  • Spin dependent tunneling (SDT) junction devices of Ta/NiFe/Ta/NiFe/FeMn/NiFe/AlOx/CoFe/NiFe/Al with in-situ naturally oxidized Al barrier were fabricated using ion beam deposition and dc sputtering in UHV chamber of 10$^{-9}$ Torr. The maximum tunneling magnetoresistance (TMR) and the product resistance by junction (R$_{j}$ A) are 16-17% and 50-60 $\Omega$${\mu}{\textrm}{m}$$^2$, respectively. The values of TMR and (R$_{j}$ A) with field annealing were slightly increased. The TMR and (R$_{j}$ A) dependence versus the junction area size was observed. These results were explained by using sheet resistance effect of bottom electrode and spin channel effects.

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