• Title/Summary/Keyword: sudden change

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An Empirical Study on the Determinants of Foreign Market Entrance of Japanese Enterprises -focusing on the Viewpoint Macro Economy- (일본기업의 해외시장 진출의 결정요인에 관한 경험적 연구 -거시경제 관점을 중심으로-)

  • Kim, il sik
    • International Area Studies Review
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    • v.13 no.3
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    • pp.385-412
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    • 2009
  • This study first analyzes economical environment change (factor) of investment nation Japan and Japanese enterprise at the analysis of Japanese enterprise's over-seas expansion factor and influence. As a result of an analysis of the factor about Japanese enterprise's overseas expansion from 1990 to 1996 and from 1998 to 2006, commonly applied factors were Yen exchange rate, interest rates, wage, enterprise profit, facility investment, and consumption expenditure. Especially, as a result of regression analysis, a sudden change of "low interest rate" was main factor at Japanese enterprise's overseas expansion from 1990 to 1996, and Japan's "Yen ex-change rate" was drawn as an important factor from 1998 to 2006. That is, from 1990 to 1996, a shock by a sudden rise in Yen value could be viewed gradually accumulated and absorbed inside Japanese economy from 1998 to 2006. Whereas it could be said that Japanese enterprise's overseas expansion was accelerated under Japanese government's overseas supporting policy and "low interest rate" together with the factor in the rise of Yen value from 1998 to 2006.

Predicting Impacts of Climate Change on Sinjido Marine Food Web (기후변화로 인한 신지도 근해 해양먹이망 변동예측)

  • Kang, Yun-Ho;Ju, Se-Jong;Park, Young-Gyu
    • Ocean and Polar Research
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    • v.34 no.2
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    • pp.239-251
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    • 2012
  • The food web dynamics in a coastal ecosystem of Korea were predicted with Ecosim, a trophic flow model, under various scenarios of primary productivity due to ocean warming and ocean acidification. Changes in primary productivity were obtained from an earth system model 2.1 under A1B scenario of IPCC $CO_2$ emission and replaced for forcing functions on the phytoplankton group during the period between 2020 and 2100. Impacts of ocean acidification on species were represented in the model for gastropoda, bivalvia, echinodermata, crustacean and cephalopoda groups with effect sizes of conservative, medium and large. The model results show that the total biomass of invertebrate and fish groups decreases 5%, 11~28% and 14~27%, respectively, depending on primary productivity, ocean acidification and combined effects. In particular, the blenny group shows zero biomass at 2080. The zooplankton group shows a sudden increase at the same time, and finally reaches twice the baseline at 2100. On the other hand, the ecosystem attributes of the mean trophic level of the ecosystem, Shannon's H and Kempton's Q indexes show a similar reduction pattern to biomass change, indicating that total biomass, biodiversity and evenness shrink dynamically by impacts of climate change. It is expected from the model results that, after obtaining more information on climate change impacts on the species level, this study will be helpful for further investigation of the food web dynamics in the open seas around Korea.

A Numerical Study on Aerodynamic Characteristics in Tunnel for High Speed Combi Train-HSB (여객/화물 복합열차 HSB의 터널 공력특성에 대한 시뮬레이션 연구)

  • Rho, Joo-Hyun
    • The KSFM Journal of Fluid Machinery
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    • v.17 no.5
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    • pp.54-59
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    • 2014
  • The new high speed combi train prototype project was developed which named HSB. It runs over the speed of 330km/h. As the speed of the train exceeds over 300km/h, due to pressure change in tunnel, aerodynamic problems such as sudden drag increase, severe acoustic noise, passenger discomfort and tunnel pressure sonic boom were occurred. This aerodynamic characteristics in tunnel should be reviewed in early design state to enhance the performance and driving quality of new high speed train. In this paper, the aerodynamic characteristics in tunnel for HSB such as pressure waves in tunnel, a rate of pressure change in cabin and micro pressure wave that cause sonic boom outside tunnel are analyzed by 2D axisymmetric CFD simulations. The results are also compared with the value for ordinary high speed train like the KTX-Sancheon. It is helpful how to design the configuration of HSB train. Finally it shows that the HSB train was well designed in tunnel condition because all values fulfill the criterions on UIC code and Korean national regulations.

The Effect of Surrounding Gas Flow on the Heat Transfer of the Falling Film Flowing Down the Outside of a Vertical Tube (수직원관 외부 유하액막 열전달에 주변 기체유동이 미치는 영향)

  • 권경민;정시영;김병주
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.14 no.12
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    • pp.996-1003
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    • 2002
  • Heat transfer characteristics were investigated for the falling film flowing down the outside of an electrically heated vertical tube. Water was used for the falling film, and its Reynolds number was varied in the range of 70~500. Because water is heated and evaporated as it flows down, both sensible and latent heat transfer should be considered. The effect of the surrounding air movement was investigated by changing the direction of the air injection; without air injection, parallel-flow, and counter-flow. For all cases, sensible teat transfer rate was almost linearly increased with the increasing film flow rate. It was found that the film heat transfer coefficient was hardly influenced by the parallel air flow. However, the counter-flow of air reduced the heat transfer coefficient, which might be caused by the uneven distribution or flooding of the film. At high heat flux, a sudden change of the film heat transfer coefficient was detected as the film flow rate reached the transition value. It is supposed that this phenomenon was caused by the change in the film flow pattern.

The Effect of Culture on Underwear Design in Renaissance era (르네상스 문화가 속옷디자인에 미친 영향)

  • Yoon Jin-A
    • Journal of the Korea Fashion and Costume Design Association
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    • v.7 no.2
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    • pp.75-85
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    • 2005
  • This study analyzed the factors of change of women's underwear in the Renaissance, which had a sudden change of shape. First, the spirit of the Renaissance was focused on human-attached importance to glamorous beauty of the body and pursued the glamorous well-proportioned figure as the ideal of the human body. This expressed a woman's beautiful curved lines by reduction of their waist size and emphasis of breast and hip lines. It also created and emphasized one's physical figure, which is a characteristic of sex. Also the materials and size of underwear cleared up the classification of class. Second, through the development of weaving techniques, more textiles were produced, from linen, the most common material used, to silk in underwear and stomacher, and chemise, which was made more splendid be devising elaborate embroidery techniques. Third, as we know that the farthingale was devised in Spain and transmitted to France because of the prevalence of printing and trade, where it changed and developed to more convenient style, this shows that information interchange was active, and we can see the phenomenon that it is developing continually through the prevalence of printing and trade.

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Development of Integrated Variable Sampling Interval EngineeringProcess Control & Statistical Process Control System (가변 샘플링간격 EPC/SPC 결합시스템의 개발)

  • Lee, Sung-Jae;Seo, Sun-Keun
    • Journal of Korean Institute of Industrial Engineers
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    • v.32 no.3
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    • pp.210-218
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    • 2006
  • Traditional statistical process control (SPC) applied to discrete part industry in the form of control charts can look for and eliminate assignable causes by process monitoring. On the other hand, engineering process control (EPC) applied to the process industry in the form of feedback control can maintain the process output on the target by continual adjustment of input variable. This study presents controlling and monitoring rules adopted by variable sampling interval (VSI) to change sampling intervals in a predetermined fashion on the predicted process levels under integrated EPC and SPC systems. Twelve rules classified by EPC schemes(MMSE, constrained PI, bounded or deadband adjustment policy) and type of sampling interval combined with EWMA chart of SPC are proposed under IMA (1,1) disturbance model and zero-order (responsive) dynamic system. Properties of twelve control rules under three patterns of process change (sudden shift, drift and random shift) are evaluated and discussed through simulation and control rules for integrated VSI EPC and SPC systems are recommended.

Advanced Frequency Estimation Technique using Gain Compensation (이득 보상에 의한 개선된 주파수 추정 알고리즘)

  • Park, Chul-Won
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.59 no.2
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    • pp.173-178
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    • 2010
  • Frequency is an important operating parameter of a power system. Due to the sudden change in generation and loads or faults in power system, the frequency is supposed to deviate from its nominal value. It is essential that the frequency of a power system be maintained very close to its nominal frequency. And monitoring and an accurate estimation of the power frequency by timing synchronized signal provided by FDR is essential to optimum operation and prevention for wide area blackout. As most conventional frequency estimation schemes are based on DFT filter, it has been pointed out that the gain error by change in magnitude could cause the defects when the power frequency is deviated from nominal value. In this paper, an advanced frequency estimation scheme using gain compensation for fault disturbance recorders (FDR) is presented. The proposed scheme can reduce the gain error caused when the power frequency is deviated from nominal value. Various simulation using both the data from EMTP package and user's defined arbitrary signals are performed to demonstrate the effectiveness of the proposed scheme. The simulation results show that the proposed scheme can provide better accuracy and higher robustness to harmonics and noise under both steady state tests and dynamic conditions.

Study on the Simulation of the 4-Stroke Cycle Spark Ignition Engines (First Paper) (4 행정 사이클 스파크 점화기관의 시뮬레이션에 관한 연구 (제1보))

  • 윤건식;우석근;서문진;신승한
    • Journal of Advanced Marine Engineering and Technology
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    • v.25 no.6
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    • pp.1260-1271
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    • 2001
  • The simulation program which predicts the gas behavior in a spark ignition engine has been developed and verified by the comparison with the experimental results foy the MPI engine, naturally aspirated and turbochared engines with a carburettor. First paper describes the calculations of the behavior of gas in the intake and exhaust system. The generalized method of characteristics including friction, heat transfer, area change and entropy gradients was used to analyse the pipe flow The constant-Pressure model was applied for the analysis of the flow through engine valved, and the constant-pressure perfect-mixing model was applied for the flow at manifold junction. The concept of the sudden area change was used for the muffler and catalytic convertor. Fer the plenum chamber in an MPI engine, constant-pressure model and constant-volume model were both examined. Through the comparison of predicted results with experiments, the simulation program was verified by showing good prediction of the behavior of IC engine qualitatively and quantitatively under wide range of operating conditions.

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Development of Realtime ECG Analysis and Monitoring System (실시간 심전도 분석 및 모니터링 시스템 개발)

  • Jeong, Gu-Young;Yoon, Myoung-Jong;Yu, Kee-Ho
    • Journal of Institute of Control, Robotics and Systems
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    • v.15 no.4
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    • pp.406-412
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    • 2009
  • ECG is used on purpose to keep good health or monitor cardiac function of aged person as well as on purpose to diagnose the disease of heart patients. The ambulatory ECG monitoring system under guarantee of safety and accuracy is very efficient to prevent the progress of heart disease and sudden death. These systems can detect the temporary change of ECG that is very significant to diagnose heart disease such as myocardial ischemia, arrhyamia and cardiac infarction. In this paper, we describe the ECG signal analysis algorithm and measurement device for ECG monitoring. The authors designed a small-size portable ECG device that consisted of instrumentation amplifier, micro-controller, filter and RF module. The device measures ECG with four electrodes on the body and detects QRS complex and ST level change in realtime. Also it transmits the measured signals to the personal computer. The developed software for ECG analysis in personal computer has the function to detect the feature points and ST level changes.

Multiple Moving Object Tracking Using The Background Model and Neighbor Region Relation (배경 모델과 주변 영역과의 상호관계를 이용한 다중 이동 물체 추적)

  • Oh, Jeong-Won;Yoo, Ji-Sang
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.39 no.4
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    • pp.361-369
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    • 2002
  • In order to extract motion features from an input image acquired by a static CCD-camera in a restricted area, we need a robust algorithm to cope with noise sensitivity and condition change. In this paper, we proposed an efficient algorithm to extract and track motion features in a noisy environment or with sudden condition changes. We extract motion features by considering a change of neighborhood pixels when moving objects exist in a current frame with an initial background. To remove noise in moving regions, we used a morphological filter and extracted a motion of each object using 8-connected component labeling. Finally, we provide experimental results and statistical analysis with various conditions and models.