• Title/Summary/Keyword: shock

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Heterogeneous Responds to Demand and Supply Oil Price Shocks: Evidence from Korea (수요와 공급 요인의 유가쇼크에 대한 한국 경제의 상이한 반응)

  • Jung, Heonyong
    • The Journal of the Convergence on Culture Technology
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    • v.4 no.3
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    • pp.93-98
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    • 2018
  • The article studies macroeconomic effects of the oil shock for Korea, which is a representative emerging economy of Asia and a small open economy. This article analyzed the macroeconomic effects of oil shocks in terms of demand and supply. In the case of Korea, oil price shocks different responds depending on factors of shock. Oil supply shock have led to a decline in industrial activity and interest rate, and oil specific demand shock have shown the greatest increase in interest rate relative to other oil price shocks. In addition, oil demand shock driven by economic activity showed that the comsumer price and the exchange rate are the largest compared to the oil shock caused by other factors. Therefore, policy makers will need to identify the source of the oil shock.

Effects of heat and ethanol shock on the membrane proteins of Vibrio vulnificus (열 및 에탄을 shock이 Vibrio vulnificus의 막단백질에 미치는 영향)

  • Heo, Moon-Soo;Jung, Cho-Rok
    • Journal of fish pathology
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    • v.12 no.2
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    • pp.89-99
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    • 1999
  • New sixteen heat shock proteins (Hsps) and ten ethanol shock proteins were appeared on the analysis with SDS-PAGE when cultivation temperature for the Vibrio vulnifrcus ATCC 27562 strain was shifted-up to $42^{\circ}C$ from $30^{\circ}C$ for 20 mins and treated with of 6% ethanol for 10 mins, respectively. Even the induction of thermotolerance in V. vulnificus was coincided with the induction of Hsps if the pre-shock was adjusted to thermal temperature. Outer membrane proteins (OMPs) that were purified from the membrane of cells after heat shock showed more immunodominant pattern to the immunized rabbit anti-V. vulnificus O serum in enzyme-linked immunosorbent assay (ELISA). On the western immunoblot analysis it was confirmed that both 62 kDa IMP and 69 kDa OMP in the Hsps and 48 kDa IMP a major OMP in the ethanol shock proteins were reacted with rabbit anti-V. vulnificus O sera. Agglutination titer of the heat shocked V. vulnificus with rabbit anti-V. vulnificus O serum was higher than that of the untreated bacteria.

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Effects of Nonequilibrium Condensation on an Oblique Shock Wave in a Supersonic Nozzle of Constant Expansion Rate (팽창률이 일정한 초음속 노즐흐름에 있어서 비평형 응축이 경사충격파에 미치는 영향)

  • 강창수;권순범;김병지;홍종우
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.14 no.5
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    • pp.1311-1319
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    • 1990
  • For the purpose of preventing the flow undulation in the cascade of steam turbine, the blades are made into a constant expansion rate in static pressure. And the flow in those cascades is transonic or supersonic in the range of 0.7-2.0 in Mach number. As a consequence, an oblique shock wave, known as inner or outer edge shock wave, arises in the flow of cascades. Especially when the steam in cascades is in a state of high wetness, nonequilibrium condensation and condensation shock wave occur, and they give rise to an interference with oblique shock wave. In the present study the case of expansion of moist air through a supersonic nozzle of constant expansion rate, which behaves similar to that of wet steam, was adopted. The effect of nonequilibrium condensation on the oblique shock wave generated by placing the wedge into the supersonic part of the nozzle was investigated. Furthermore, the relationship between nonequilibrium condensation zone and incident point of the oblique shock wave, oblique shock wave angle, the variations of angles of incident and reflected shock waves due to the variation of initial stagnation supersaturation and the relationship between the height of Mach stem and initial stagnation supersaturation are discussed.

Synthesis and thermotolerance of heat shock proteins in campylobacter jejuni (Campylobacter jejuni에서 고온충격 단백질의 합성과 내열성)

  • 김치경;김현옥;이길재
    • Korean Journal of Microbiology
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    • v.29 no.1
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    • pp.49-55
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    • 1991
  • The heat shock responses of Campylobacter jejuni were studied by examination of their survival rates and synthesis of heat shocd proteins. When C. jejuni cells were treated at the sublethal temperatures of 48.deg.C for 30 minutes, most of the cells maintained their viabilities and synthesized the heat shock proteins of 90, 73, and 66 kD in molecular weight. By the method of two-dimensional electrophoresis, the heat shock proteins of C. jejuni were identified to be Hsp90, Hsp73, and Hsp66. During the heat shock at 48.deg.C, the heat shock proteins were induced from about 5 minutes after the heat shock treatment. Their synthesis was continued upto 30 minutes, but remarkably retarded after 50 minutes. When C. jejune cells were heat shocked at 51.deg.C for 30 minutes, the survival rates of the cells were decreased by about $10^{3}$ fold and synthesis of heat shock proteins and normal proteins was also generally retarded. The cells exposed to 55.deg.C for 30 minutes died off by more than $10^{5}$ cells and the new protein synthesis was not observed. But when C. jejuni cells were heat-shocked at the sublethal temperature of 48.deg.C for 15 to 20 minutes and then were exposed at the lethal temperature of 55.deg.C for 30 minutes, their viabilities were higher than those exposed at 55.deg.C for 30 minutes without pre-heat shock at 48.deg.C. Therefore, the heat shock proteins synthesized at the sublethal temperature of 48.deg.C in C. jejuni were thought to be responsible for thermotolerance. However, when C. jejuni cells heat-shocked at various ranges of sublethal and lethal temperatures were placed back to the optimum temperature of 42.deg.C, the multiplication patterns of the cells pretreated at different temperatures were not much different each other.

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Shock Thyroid in a Patient with Septic Shock: A Case Report and Literature Review (패혈성 쇼크 환자에서 동반된 쇼크 갑상샘: 증례 보고 및 문헌 고찰)

  • Wang Hyon Kim;Min Seon Kim;Jun Ho Kim;Kyung Hee Lee;Jung Hwan Lee
    • Journal of the Korean Society of Radiology
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    • v.82 no.5
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    • pp.1328-1333
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    • 2021
  • Shock thyroid is a rare manifestation of the CT hypotension complex and can be diagnosed when thyroid and perithyroidal edemas are observed on CT during the onset of shock. Shock thyroid can be a useful CT sign for decompensated shock. This condition is reversible and recovers rapidly with adequate treatment. We present the case of an 84-year-old female with septic shock, exhibiting CT features consistent with a shock thyroid. We also reviewed the clinical and radiological findings reported in the literature. The present case emphasizes that shock thyroid can be an early indicator of impending hemodynamic instability and has important prognostic and therapeutic implications.

Shock Reflection and Penetration Impinging into a Vortex (I) - Experimental Model- (와동에 입사하는 충격파의 반사 및 투과(I))

  • Jang, Se-Myeong;Jang, Geun-Sik
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.26 no.9
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    • pp.1311-1318
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    • 2002
  • An experimental model is investigated in this paper using the experimental method with a shock tube and the numerical technique. The shock-vortex interaction generated by this model is visualized with various methods: holographic interferometry, shodowgraphy, and numerical computation. In terms of shock dynamics, there are two meaningful physics in the present problem. They are reflective wave from the slip layer at the vortex edge and transmitted shock penetrating the vortex core. The discussion in this study is mainly focused on the two kinds of waves contributing to the quadrupolar pressure distribution around the vortex center during the interaction.

Anti-shock Controller Design for Optical Disk Drive Systems with Nonlinear Controller (광디스크 드라이브 시스템을 위한 비선형 제어기를 이용한 Anti-Shock 제어기 설계)

  • Baek, Jong-Shik;Chung, Chung-Choo
    • Proceedings of the KIEE Conference
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    • 2004.11c
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    • pp.675-677
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    • 2004
  • This paper presents a nonlinear controller design for optical disk drive systems to improve anti-shock performance. The nonlinear anti-shock controller is added parallel to the original linear servo control loop. In the previous work, dead-zone nonlinear element is used for nonlinear controller and PID control method is used for linear controller. Although this strategy improves anti-shock performance, it has a narrow stability bound. In this paper, we propose dead-zone with saturation nonlinear element for the nonlinear controller. Since this nonlinear element improves stability margin, we can use higher gain of dead-zone than the controller with dead-zone only. In the linear controller design, we show that lead-lag control has improved stability margin over PID control. Numerical simulation results show that the proposed method can get better performance to the external shock than previously proposed method.

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A Study on the Vehicle Dynamic Characteristic of Displacement Sensitive Shock Absorber (변위감응형 충격흡수기의 차량 동력학적 특성에 관한 연구)

  • 이춘태;곽동훈;정봉호;이진걸
    • Journal of the Korean Society for Precision Engineering
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    • v.20 no.1
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    • pp.187-195
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    • 2003
  • The performance of shock absorber is directly related to the car behaviour and performance, both for handling and ride comfort. The displacement sensitive shock absorber has two modes of damping force (i.e. soft and hard) according to the position of piston. In this study, a mathematical nonlinear dynamic model is introduced to predict the performance of displacement sensitive shock absorber. Especially in this paper, the transient zone is considered and the simulation result is well fit with experimental data. And the vehicle dynamic characteristic of displacement sensitive shock absorber is presented using quarter car simulation model. The simulation results of frequency response are compared with passive shock absorber.

A Study on Dynamic Characteristics of Automotive Shock Absorber (자동차용 충격 흡수기의 동특성 연구)

  • 남경탁;황성원;신귀수
    • Journal of the Korean Society of Safety
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    • v.17 no.3
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    • pp.1-6
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    • 2002
  • A dynamic characteristics of shock absorber in the various excitation is investigated experimentally. Work diagrams and characteristic curves are used as a experimental standard. The various excitation conditions temperature and noise are very important factors in associated with the reduction of damping force. It is found that the heat occurrence from shock absorber, the gas shock absorber is much higher than oil shock absorber and increased in high speed. As to the variation of damping force, there are no change when the speed is low but we fixed amount of variation by increasing speed and change of new and old decrease. The sound pressure of the swash noise from cycle of shock absorber, we compared with theory sound pressure by experiment.

Experimental and Computational Studies of the Pulse Wave Impinging upon a Vertical Flat Plate (수직평판에 충돌하는 펄스파에 관한 실험적/수치해석적 연구)

  • 이동훈;김희동;강성황
    • Journal of KSNVE
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    • v.11 no.2
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    • pp.285-291
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    • 2001
  • The impingement of a weak shock wane discharged from the open end of a shock tube upon a flat plate was investigated using shock tube experiments and numerical simulations. Harten-Yee Total Variation Diminishing method was used to solve axisymmetric, unsteady, compressible flow governing equations. Experiments were carried out to validate the present computations. The effects of the flat plate and baffle plate sizes on the impinging flow field over the flat plate were investigated. Shock Mach number was varied in the range from 1.05 to 1.20. The distance between the plate and shock tube was changed to investigate the effect on the peak pressure. From both the results of experiments and computations we obtained a good empirical equation to predict the peak pressure on the flat plate.

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