• Title/Summary/Keyword: model B3

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Prediction of the Spawning Ground of Todarodes pacificus under IPCC Climate A1B Scenario (IPCC 기후변화 시나리오(A1B)에 따른 살오징어(Todarodes pacificus) 산란장의 변동 예측)

  • Kim, Jung-Jin;Min, Hong-Sik;Kim, Cheol-Ho;Yoon, Jin-Hee;Kim, Su-Am
    • Ocean and Polar Research
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    • v.34 no.2
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    • pp.253-264
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    • 2012
  • In the northwestern Pacific, spawning of the common squid, Todarodes pacificus, occurs at continental shelf and slope areas of 100-500 m, and the optimum temperature for the spawning and survival of paralarvae is assumed to be $18-23^{\circ}C$. To predict the spawning ground of Todarodes pacificus under future climate conditions, we simulated the present and future ocean circulations, using an East Asia regional ocean model (Modular Ocean Model, MOM version3), projected by two different global climate models (MPI_echam5, MIROC_hires), under an IPCC SRES A1B emission scenario. Mean climate states for 1990-1999 and 2030-2039 from 20th and 21th Century Climate Change model simulation (from the IPCC 4th Assessment Report) were used as surface conditions for simulations, and we examined changes in spawning ground between the 1990s and 2030s. The results revealed that the distribution of spawning ground in the 2030s in both climate models shifted northward in the East China Sea and East Sea, for both autumn and winter populations, compared to that of the 1990s. Also, the spawning area (with $1/6^{\circ}{\times}1/6^{\circ}$ grid) in the 2030s of the autumn and winter populations will decline by 11.6% (MPI_echam5) to 30.8% (MIROC_hires) and 3.0% (MPI_echam5) to 18.2% (MIROC_hires), respectively, from those of the 1990s.

Study of the Effect and Underlying Mechanism of Enzyme-Treated Garlic Extract on a Lipopolysaccharide-Induced Acute Colitis Model (효소처리를 이용한 마늘 추출물이 Lipopolysaccharide 유발 급성 장염 모델에 미치는 효과 및 기전 연구)

  • Min Ju Kim;Mi-Rae Shin;Hak Joo Choi;Seong-Soo Roh
    • The Journal of Internal Korean Medicine
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    • v.44 no.6
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    • pp.1243-1255
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    • 2023
  • Objective: This study aims to explore the pharmacological effects and mechanisms of enzyme (Viscozyme)-treated garlic extract (EG) in an animal model of acute enteritis induced by lipopolysaccharide (LPS). Methods: The experiment included four subgroups: normal, control, EG200 (treated with 200 mg/kg EG), and EG400 (treated with 400 mg/kg EG). Drug administration lasted 3 days, followed by the induction of acute enteritis in all groups (except normal) through the intraperitoneal administration of 20 mg/kg of LPS 1 h after the last oral dose. Autopsy was conducted 24 h later to collect serum and colon tissue. Serum was analyzed for reactive oxygen species (ROS) and C-reactive protein (CRP), while Western blotting was performed on the colon tissue. Results: After analyzing the ROS and CRP levels in serum, the EG treatment group exhibited a significant decrease compared with the control group. The EG treatment group exhibited a significant decrease in the activation of the mitogen-activated protein kinases (MAPKs)/nuclear factor-kappa B p65 (NF-κB) pathway compared with the control group. EG administration significantly regulated apoptosis-related factors, including B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X, cysteine aspartyl-specific protease-3, and cytochrome C. Conclusions: EG treatment in mice with LPS-induced acute colitis reduced the ROS and CRP levels, suppressed the MAPKs/NF-κB pathway in the colon, and effectively alleviated acute enteritis by modulating apoptosis-related factors. Based on these findings, EG emerges as a promising candidate for the prevention and treatment of acute colitis, showing its potential therapeutic efficacy in this experimental model.

A Review of SiC Static Induction Transistor (SIT) Development for High-Frequency Power Amplifiers

  • Sung, Y.M.;Casady, J.B.;Dufrene, J.B.
    • KIEE International Transactions on Electrophysics and Applications
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    • v.11C no.4
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    • pp.99-106
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    • 2001
  • An overview of Silicon Carbide (SiC) Static Induction Transistor (SIT) development is presented. Basic conduction mechanisms are introduced and discussed, including ohmic, exponential, and space charge limited conduction (SCLC) mechanisms. Additionally, the impact of velocity saturation and temperature effects on SCLC are reviewed. The small-signal model, breakdown voltage, power density, and different gate structures are also discussed, before a final review of published SiC SIT results. Published S-band (3-4 GHz) results include 9.5 dB of gain and output power of 120 W, and L-band (1.3 GHz) results include 400 W output power, 7.7 dB of gain, and power density of 16.7 W/cm.

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On Reasonable Boundary Condition for Inclined Seabed/Structure in Case of the Numerical Model with Quadrilateral Mesh System (사각격자체계 수치모델에서의 경사면 처리기법에 관하여)

  • Hur, Dong-Soo;Lee, Woo-Dong;Bae, Ki-Seong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.5B
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    • pp.591-594
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    • 2008
  • Present study aims at the development of a reasonable boundary condition for a structure over inclined seabed in case of the numerical model with quadrilateral mesh system. The technique for the inclined impermeable/permeable boundary in the quadrilateral mesh is newly proposed. The new technique and LES-WASS-3D model (Hur and Lee, 2007) have been used for the investigation of the dynamics of fluid field, and validated through the comparison with a typical stair-type boundary condition. 3-Dimensional numerical model with Large Eddy Simulation is called LES-WASS-3D, and is able to simulate directly interaction of WAve Structure Sea bed/Sandy beach.

Intergenerational Transmission of Attachment: Mother's Internal Working Model of Relationships and Infant Attachment Patterns (애착의 세대간 전이 - 어머니의 내적 실행모델과 영아의 애착유형 -)

  • Jang, Mi Ja;Choi, Bok Hee
    • Korean Journal of Child Studies
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    • v.20 no.1
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    • pp.147-164
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    • 1999
  • The purpose of this study was to investigate (1) intergenerational transmission from mother's internal working model of relationships formed in her childhood and infant's attachment patterns and (2) the associations among maternal working models, maternal sensitivity, and infant attachment patterns. The subjects were twenty 12- to 20-month-old infants and their mothers. The Adult Attachment Interview (1996) was used to assess mother's internal work model of relationships. Interviews were audio-recorded and transcribed verbatim. Each dyad was videotaped in the modified Ainsworth Strange Situation(1978) and filmed for 3 minutes in the Questionaire Situation of Smith and Pederson (1988). Mothers were classified as autonomous(F), dismissing(Ds), preoccupied(E), or unresolved/disorganized(Ud). Infants were classified as secure(B), insecure-avoidant(A), or insecure-resistant(C). Exact A/B/C/D and Ds/F/E/Ud agreement was observed in 55% of the dyads. Maternal sensitivity was related to infant attachment patterns but not to maternal working models.

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A Novel MRAS Based Sensorless Speed Control of Induction Motor (새로운 MRAS에 의한 유도전동기의 센서리스 속도제어)

  • Jin, Dae-Won;Gwon, Yeong-An
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.48 no.3
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    • pp.124-130
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    • 1999
  • Speed and position sensors require the additional mounting space, reduce the reliability in harsh environments and increase the cost of motor. Various control algorithms have been proposed for the elimination of speed senor. This paper investigates a novel speed sensorless control of induction motor. The proposed control strategy is based on MRAS(Model Reference Adaptive System) using state observer as a reference model for flux estimation. This algorithm may overcome several shortages of conventional MRAS: integrator problems, small EMF at low speed and relatively large sensitivity to resistance variation. The proposed algorithm is verified through simulation and experiment.

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Measurement of Infinitesimal Delaminaton Thickness by Echo Amplitude of Ultrasonic Wave (초음파의 에코 높이를 이용한 미소(微小) 박리(剝離) 두께 측정에 관한 연구)

  • Han, E.K.;Jang, K.Y.;Hwang, B.I.;Lee, B.S.;Park, I.G.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.13 no.1
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    • pp.21-28
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    • 1993
  • If the infinitesimal delamination exists and the two waves can hardly be distinguished from each other on account of being much closer, we cannot measure the thickness of delamination by the time difference method. On this study, we calculated the thickness of infinitesimal delamination model by means of measuring echo height due to the deflection of material particles and utilized Newton Ring for optical measurement as a delamination model. From the result of Newton Ring expressed in the delamination model, we can calculate the infinitesimal delamination thickness up to $0.2{\sim}0.3{\mu}m$ due to the difference of acoustic impedance by the ratio of the echo height to the total reflection.

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The Characteristics of Hydraulic Valve for a Passive Reactor (피동형 원자로의 Hydraulic Valve 특성 실험)

  • Kim, Sang-Nyung;Kim, Yoong-Seock
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.22 no.8
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    • pp.1083-1090
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    • 1998
  • A kind of three-way check valve, so called hydraulic calve was proposed for the substitute of the density lock of passive reactor such as SPWR (System-Integrated Pressurized Water Reactor). The function of the valve are the separation of the borated water from main coolant loop for normal operation and the insurge of the water into the loop for shutdown and the removal of the decay power when the main coolant flow rate is not enough. To verify the operability and the characteristics of the valve, experimental works were executed with 1/3 scale model calve. Also a diffuser model was proposed for the theoretical analysis of the valve.

Theoretical Analysis of Carbon Nanotube Actuators (탄소나노튜브 작동기의 이론적 해석)

  • Park C.H.;Park H.C.;So H.K.;Jung B.B.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.06a
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    • pp.927-931
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    • 2005
  • Carbon nanotube actuator, working under physical conditions (in aqueous solution) and converting electrical energy into mechanical energy directly, can be a good substitute for artificial muscle. The carbon nanotube actuator simulated in this paper is an isotropic cantilever type with an adhesive tape which is sandwiched between two single-walled carbon nanotubes. For predicting the static and dynamic characteristic parameters, the analytical model for a 3 layer bimorph carbon nanotube actuator is developed by using Euler-Bernoulli beam theory. The governing equation and boundary conditions are derived from energy principles. The induced displacements of the theoretical model are presented in order to investigate the performance of the carbon nanotube actuator with different control voltages. The developed model presents invaluable means for designing and predicting the performance of carbon nanotube actuator that can be used in artificial muscle applications.

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Numerical analysis of blood flow in the cactus type KTAH (선인장 형태의 한국형 인공심장 내 3차원 혈류의 수치적 해석)

  • Park M.S.;Ko H.J.;Min B.G.;Shim E.B.
    • Proceedings of the KSME Conference
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    • 2002.08a
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    • pp.695-696
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    • 2002
  • Three-dimensional blood flow in the sac of the KTAH(Korean total artificial heart) is simulated using fluid-structure interaction model. The aim of this study is to delineate the three-dimensional unsteady-blood flow in the sac of KTAH. Incompressible viscous flow is assumed for blood using the assumption of Newtonian fluid. The numerical method employed in this study is the finite element software called ADINA. Fluid-structure interaction model between blood and sac is utilized to represent the deformation of the sac by the rigid moving actuator. Three-dimensional geometry of cactus type KTAH is chosen for numerical model with prescribed pressure boundary condition on the sac surface. Blood flow is generated by the motion of moving actuator and strongly interacts with the solid material surrounding blood. High shear stress is observed mainly near the inlet and outlet of the sac.

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