• 제목/요약/키워드: junction

검색결과 3,323건 처리시간 0.023초

Spinal Gap Junction Channels in Neuropathic Pain

  • Jeon, Young Hoon;Youn, Dong Ho
    • The Korean Journal of Pain
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    • 제28권4호
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    • pp.231-235
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    • 2015
  • Damage to peripheral nerves or the spinal cord is often accompanied by neuropathic pain, which is a complex, chronic pain state. Increasing evidence indicates that alterations in the expression and activity of gap junction channels in the spinal cord are involved in the development of neuropathic pain. Thus, this review briefly summarizes evidence that regulation of the expression, coupling, and activity of spinal gap junction channels modulates pain signals in neuropathic pain states induced by peripheral nerve or spinal cord injury. We particularly focus on connexin 43 and pannexin 1 because their regulation vastly attenuates symptoms of neuropathic pain. We hope that the study of gap junction channels eventually leads to the development of a suitable treatment tool for patients with neuropathic pain.

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

  • 천창율;정진교
    • 산업기술연구
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    • 제13권
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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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LED 기생 커패시턴스를 고려한 접합온도 측정 시스템의 개선 (Improvement the Junction Temperature Measurement System Considering the Parasitic Capacitance in LED)

  • 박종연;유진완
    • 산업기술연구
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    • 제29권B호
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    • pp.187-191
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    • 2009
  • Recently, we have used LEDs to illumination because it has a high luminous efficiency and prolong lifespan. However the light power and lifetime is reduced by junction temperature increment of LED. So it is important to measure the junction temperature accurately. In case of using a electrical method measuring junction temperature of LED. Temperature measurement errors are spontaneously generated because of a parasitic capacitances in LED. In this paper, we proposed a method that reducing LED's parasitic capacitance effects for electrical measurement. It was demonstrated by the experimental result that is more correct than established method.

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트랩을 통한 열적 천이와 터널링 천이를 동시에 고려할 수 있는 새로운 터널링 모델에 관한 연구 (New Tunneling Model Including both the Thermal and the Tunneling Transition through Trap)

  • 박장우;곽계달
    • 전자공학회논문지A
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    • 제29A권8호
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    • pp.71-77
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    • 1992
  • According to increasing the doping concentration in p-n junction, a tunneling current through trap as well as SRH(Shockley-Read-Hall) generation-recombination current in depletion region occurs. It is the tunneling current that is a dominant current at the forward bias. In this paper, the new tunneling-recombination equation is derived. The thermal generation-recombination current and tunneling current though trap can be easily calculated at the same time because this equation has the same form as the SRH generation-recombination equation. For the validity of this equation, 2 kind of samples are simulated. The one is $n^{+}$-p junction device fabricated with MCT(Mercury Cadmium Telluride, mole fraction=0.29), the other Si n$^{+}-p^{+}$ junction. From the results for MCT $n^{+}$-p junction device and comparing the simulated and expermental I-V characteristics for Si n$^{+}-p^{+}$ junction, it is shown that this equation is a good description for tunneling through trap and thermal generation-recombination current calculation.

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Oxygen-Silver Junction Formation for Single Molecule Conductance

  • Jo, Han Yeol;Yoo, Pil Sun;Kim, Taekyeong
    • 대한화학회지
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    • 제59권1호
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    • pp.18-21
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    • 2015
  • We use a scanning tunneling microscope based break-junction technique to measure the conductance of a 4,4'-dimethoxybiphenyl molecular junction formed with Ag and Au electrodes. We observe the formation of a clear molecular junction with Ag electrodes that result from stable Ag-oxygen bonding structures. However we have no molecular bonding formation when using Au electrodes, resulting in a tunneling current between the top and bottom metal electrodes. We also see a clear peak in the conductance histogram of the Ag-oxygen molecular junctions, but no significant molecular features are seen with Au electrodes. Our work should open a new path to the conductance measurements of single-molecule junctions with oxygen linkers.

Conductance of a Single Molecule Junction Formed with Ni, Au, and Ag Electrodes

  • Kim, Taekyeong
    • 대한화학회지
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    • 제58권6호
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    • pp.513-516
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    • 2014
  • We measure the conductance of a 4,4'-diaminobiphenyl formed with Ni electrodes using a scanning tunneling microscope-based break-junction technique. For comparison, we use Au or Ag electrodes to form a metal-molecular junction. For molecules that conduct through the highest occupied molecular orbital, junctions formed with Ni show similar conductance as Au and are more conductive than those formed with Ag, consistent with the higher work function for Ni or Au. Furthermore, we observe that the measured molecular junction length that is formed with the Ni or Au electrodes was shorter than that formed with the Ag electrodes. These observations are attributed to a larger gap distance of the Ni or Au electrodes compared to that of the Ag electrodes after the metal contact ruptures. Since our work allows us to measure the conductance of a molecule formed with various electrodes, it should be relevant to molecular electronics with versatile materials.

Lattice Boltzmann 법을 이용한 Cross-Junction 채널 내의 droplet 유동에 관한 수치해석적 연구 (Numerical Study on the Droplet Flows in a Cross-Junction Channel Using the Lattice Boltzmann Method)

  • 박재현;서용권
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2006년 창립20주년기념 정기학술대회 및 국제워크샵
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    • pp.407-410
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    • 2006
  • This study describes a simulation of two-dimensional bubble forming and motion by the Lattice Boltzmann Method with the phase field equation. The free energy model is used to treat the interfacial force and deformation of binary fluids system, drawn into a T-junction the micro channel. A numerical simulation of a binary flow in a cross-junction channel is carried out by using the parallel computation method. The aim in this investigation is to examine the applicability of LBM to numerical analysis of binary fluid separation and motion in the micro channel.

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직접변환 수신기를 위한 상관기용 6-단자 설계 (Design of a 6-Port Junction for Direct Conversion Receiver(DCR))

  • 이승섭;지기만;박동철
    • 한국전자파학회:학술대회논문집
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    • 한국전자파학회 2003년도 종합학술발표회 논문집 Vol.13 No.1
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    • pp.299-303
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    • 2003
  • A miniaturized 6-port junction using tandem couplers is presented. The proposed 6-port junction is designed at the center frequency of 5 GHz. The size reduction of the 6-port junction is achieved by replacing the $90^{\circ}$ hybrids with the tandem couplers. The magnitude imbalance and the phase imbalance of the proposed 6-port junction are similar with those of the conventional one.

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대용량 전력변환용 초접합 IGBT 개발에 관한 연구 (The Develop of Super Junction IGBT for Using Super High Voltage)

  • 정헌석;강이구
    • 한국전기전자재료학회논문지
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    • 제28권8호
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    • pp.496-500
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    • 2015
  • This paper was proposed the theoretical research and optimal design 3000V super junction NPT IGBT for using electrical automotive and power conversion. Because super junction IGBT was showed ultra low on resistance, it was structure that can improve the thermal characteristics of conventional NPT IGBT. The electrical characteristics of super junction NPT IGBT were 2.52 V of on state voltage drop, 4.33 V of threshold voltage and 2,846 V breakdown voltage. We did not obtaing 3,000 V breakdown voltage but we will obtain 3,000 V breakdown voltage through improving p pillar layer. If we are carried this research, This device will be used electrical automotive, power conversiton and high speed train.

Effect of Flow Direction on Two-Phase Flow Distribution of Refrigerants at a T-Junction

  • Tae Sang-Jin;Cho Keum-Nam
    • Journal of Mechanical Science and Technology
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    • 제20권5호
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    • pp.717-727
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    • 2006
  • The present study experimentally investigated the effect of flow direction and other flow parameters on two-phase flow distribution of refrigerants at a T-junction, and also suggested a prediction model for refrigerant in a T-junction by modifying previous model for air-water flow. R-22, R-134a, and R-410A were used as test refrigerants. As geometric parameters, the direction of the inlet or branch tube and the tube diameter ratio of branch to inlet tube were chosen. The measured data were compared with the values predicted by the models developed for air-water or steam-water mixture in the literature. We propose a modified model for application to the reduced T-junction and vertical tube orientation. Among the geometric parameters, the branch tube direction showed the biggest sensitivity to the mass flow rate ratio for the gas phase, while the inlet quality showed the biggest sensitivity to the mass flow rate ratio among the inlet flow parameters.