• 제목/요약/키워드: Movement variability

검색결과 101건 처리시간 0.022초

외환위기 전후 주식시장의 변동성에 관한 융복합 분석 - 정규분포, 첨도, 왜도를 중심으로 (Convergence analysis about volatility of the stock markets before and after the currency crisis - With a focus on Normal distribution, kurtosis, skewness)

  • 최정일
    • 디지털융복합연구
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    • 제13권8호
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    • pp.153-160
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    • 2015
  • 국내 주식시장은 1997년 9월 외환위기 이후 커다란 변화를 겪게 되었다. 외환위기 이후 국내 금융시장이 개방되면서 해외자본이 주식시장과 채권시장, 외환시장으로 들어왔다 나가기를 반복하고 있다. 국내 주식시장은 외환위기 이전에는 대부분 국내 자본에 의해 영향을 받아왔다. 그러나 외환위기 이후에는 해외자본에 의해 절대적인 영향을 받아오고 있다. 본 연구의 목적은 두 구간의 동향을 살펴보고 외환위기 이후 종합주가지수의 변동성에 어떠한 변화가 나타나고 있는지 분석하는데 있다. 이를 위해 본 연구는 두 구간의 차이를 살펴보고자 일간과 주간, 월간의 정규분포와 첨도, 왜도를 구하여 두 구간의 변동성과 기울임 현상을 분석하고자 한다. 이를 바탕으로 향후 국내 주식시장의 움직임도 예측하고자 한다. 분석 결과 외환위기 이후 등락폭은 감소하였으나 중장기적으로 종합주가지수의 방향성은 상대적으로 뚜렷하게 나타나고 있다. 이를 근거로 향후 국내시장은 방향성을 보면서 중장기적인 투자가 바람직해 보인다.

Evaluation of Erosivity Index (EI) in Calculation of R Factor for the RUSLE

  • Kim, Hye-Jin;Song, Jin-A;Lim, You-Jin;Chung, Doug-Young
    • 한국토양비료학회지
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    • 제45권1호
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    • pp.112-117
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    • 2012
  • The Revised Universal Soil Loss Equation (RUSLE) is a revision of the Universal Soil Loss Equation (USLE). However, changes for each factor of the USLE have been made in RUSLE which can be used to compute soil loss on areas only where significant overland flow occurs. RUSLE which requires standardized methods to satisfy new data requirements estimates soil movement at a particular site by utilizing the same factorial approach employed by the USLE. The rainfall erosivity in the RUSLE expressed through the R-factor to quantify the effect of raindrop impact and to reflect the amount and rate of runoff likely is associated with the rain. Calculating the R-factor value in the RUSLE equation to predict the related soil loss may be possible to analyse the variability of rainfall erosivity with long time-series of concerned rainfall data. However, daily time step models cannot return proper estimates when run on other specific rainfall patters such as storm and daily cumulative precipitation. Therefore, it is desirable that cross-checking is carried out amongst different time-aggregations typical rainfall event may cause error in estimating the potential soil loss in definite conditions.

기관사의 각성상태 평가를 위한 소형 피부전기활성도 측정 시스템 개발 (Development of the Electrodermal Activity Monitoring System for the Evaluation of Train Driver's Arousal State)

  • 임민규;이영재;이강휘;강승진;김경남;박희정;양희경;이정환
    • 전기학회논문지
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    • 제63권9호
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    • pp.1286-1293
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    • 2014
  • Typically, studies through the simulation system have been progressed, because the evaluation of the driver's arousal state about the service of a actual train has risk of safety for the driver. When configured event same as the real in simulation system, the ability to cope with an accident situation may be the same each other. But the difference in the state of tension or arousal will occur. In this study, requested to cooperate with the railways in order to escape from these constraints, and the target of the experiment was to real engineer service. I was set about experiment when the train was stopped as safe as possible. As a result, the beta wave of EEG signals that representing complex calculations or anxiety is increased rapidly on the basis of a flag station from at the time of departure. The size of the electrodermal activity signal in response to movement of the body gave a noticeable. In terms of HRV, if the train approach a flag station gradually and the R-R interval is narrowed. So that the driver can be estimated as arousal state. In accordance with this study, if the quantitative standard of arousal state be based on the driver's biosignals will provide, it will be able to take advantage of development the system that would prevent train accidents caused by human error.

기후변화가 중서부태평양 가다랑어(Katsuwonus pelamis)의 어획분포와 생물학적 특성에 미친 영향 (Effects of Climate-induced Variation in the Catch Distribution and Biological Characteristics of Skipjack Tuna Katsuwonus pelamis in the Western and Central Pacific Ocean)

  • 김은정;문대연;김수암
    • 한국수산과학회지
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    • 제48권4호
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    • pp.489-497
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    • 2015
  • To reveal the spatial and temporal variability in the distribution, growth, and maturation of skipjack tuna Katsuwonus pelamis in the western tropical Pacific, we compared two El $Ni{\tilde{n}}o$-Southern Oscillation (ENSO) signals and the sea surface temperature (SST) in the main fishing area with fishery and biological data. An index of skipjack tuna distribution was calculated using Korean purse seine fishery data from 1985 to 2003. Biological data for skipjack tuna were collected monthly from Korean catches during the 1994-2003 period. The catch was more closely related to the SST in the main fishing area than to the ENSO signals. However, cross-correlated function analysis showed delayed interactions between abiotic and biotic factors. The El $Ni{\tilde{n}}o$ events preceded the eastward movement of the fishing center by 2-3 months. El $Ni{\tilde{n}}o$ had a positive effect on the skipjack tuna catch, and the change in the Southern Oscillation Index (SOI) preceded the catch fluctuation by ca. 5-7 months. In addition, negative El $Ni{\tilde{n}}o$ effects on gonad maturation and the mean length of skipjack tuna were detected with time lags of 12 and 7 months, respectively. The length frequency indicated that the regime-specific growth pattern at each discrete period seemed to be related to the ENSO.

SATELLITE DETECTION OF RED TIDE ALGAL BLOOMS IN TURBID COASTAL WATERS

  • Ahn, Yu-Hwan;Shanmugam, Palanisamy
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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    • pp.471-474
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    • 2006
  • Several planktonic dinoflagellates, including Cochlodinium polykrikoides (p), are known to produce red tides responsible for massive fish kills and serious economic loss in turbid Northwest Pacific (Korean and neighboring) coastal waters during summer and fall seasons. In order to mitigate the impacts of these red tides, it is therefore very essential to detect, monitor and forecast their development and movement using currently available remote sensing technology because traditional ship-based field sampling and analysis are very limited in both space and temporal frequency. Satellite ocean color sensors, such as Sea-viewing Wide Field-of-view Sensor (SeaWiFS), are ideal instruments for detecting and monitoring these blooms because they provide relatively high frequency synoptic information over large areas. Thus, the present study attempts to evaluate the red tide index methods (previously developed by Ahn and Shanmugam et al., 2006) to identify potential areas of red tides from SeaWiFS imagery in Korean and neighboring waters. Findings revealed that the standard spectral ratio algorithms (OC4 and LCA) applied to SeaWiFS imagery yielded large errors in Chl retrievals for coastal areas, besides providing false information about the encountered red tides in the focused waters. On the contrary, the RI coupled with the standard spectral ratios yielded comprehensive information about various ranges of algal blooms, while RCA Chl showing a good agreement with in-situ data led to enhanced understanding of the spatial and temporal variability of the recent red tide occurrences in high scattering and absorbing waters off the Korean and Chinese coasts. The results suggest that the red tide index methods for the early detection of red tides blooms can provide state managers with accurate identification of the extent and location of blooms as a management tool.

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장수명 공동주택 유지관리를 위한 프로세스 구축에 대한 연구 (The Development of Maintenance Process in Long-Life Housing)

  • 지장훈;김수암;윤상조
    • 한국주거학회논문집
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    • 제21권3호
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    • pp.115-124
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    • 2010
  • The environment which has been destroyed for the national growth since 1960's would seem to offer infinite resources to human, but now, the existence of human being is threatened by the development thoughtless for the environment. The World Powers have concentrated on green growth with eco-friendly resource since the end of 20th century. Korea suggested that the vision was the low carbon for green growth in 2008. It is necessary to supply Long-Life Housing in the green technology in terms of the sustainable housing development based on various life style, life cycle of the residences, the restrain remodeling and redevelopment in construction. This study is aim to establish the development of maintenance process to make continuous inhabitation of Long-Life Housing that has the separated SI for maintenance, durability, variability and remodeling. The maintenance for Long-Life Housing is very important to have more than 50~70 years the long term of life cycle in comparison with Housing. Also, the roles of manager and user are important parts in Long-Life Housing. The present maintenance for Housing is shift and repair works by the routine maintenance and demage. However, The maintenance for Long-Life Housing should consider movement and flexibility. In addition, Long-Life Housing requires the proper process of maintenance because it is different from Housing in housing concept, design and constructions stage. Therefore this study shows the efficient maintenance process for Long-Life Housing.

Dynamically Induced Anomalies of the Japan/East Sea Surface Temperature

  • Trusenkova, Olga;Lobanov, Vyacheslav;Kaplunenko, Dmitry
    • Ocean and Polar Research
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    • 제31권1호
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    • pp.11-29
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    • 2009
  • Variability of sea surface temperature (SST) in the Japan/East Sea (JES) was studied using complex empirical orthogonal function (CEOF) analysis. Two daily data sets were analyzed: (1) New Generation 0.05o-gridded SST from Tohoku University, Japan (July 2002-July 2006), and (2) 0.25o-gridded SST from the Japan Meteorological Agency (October 1993-November 2006). Linkages with wind stress curl were revealed using 6-h 1o-gridded surface zonal and meridional winds from ancillary data of the Sea- WiFS Project, a special National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) product (1998-2005). SST anomalies (SSTA) were obtained by removing the seasonal signal, estimated as the leading mode of the CEOF decomposition of the original SST. Leading CEOF modes of residual SSTA obtained from both data sets were consistent with each other and were characterized by annual, semiannual, and quasi-biennial time scales estimated with 95% statistical significance. The Semiannual Mode lagged 2 months behind the increased occurrence of the anticyclonic (AC) wind stress curl over the JES. Links to dynamic processes were investigated by numerical simulations using an oceanic model. The suggested dynamic forcings of SSTA are the inflow of subtropical water into the JES through the Korea Strait, divergence in the surface layer induced by Ekman suction, meridional shifts of the Subarctic Front in the western JES, AC eddy formation, and wind-driven strengthening/weakening of large-scale currents. Events of west-east SSTA movement were identified in July-September. The SSTA moved from the northeastern JES towards the continental coast along the path of the westward branch of the Tsushima Current at a speed consistent with the advective scale.

3D프린팅을 이용한 사용자 맞춤형 의수 개발 (Development of Customized Prosthetic Hand Using 3D Printing)

  • 문미경
    • 융합신호처리학회논문지
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    • 제19권3호
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    • pp.110-117
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    • 2018
  • 의수나 의족장치 개발은 전 세계적으로 꾸준히 이루어지고 있으며, 사람의 손과 똑같이 만들어 내거나 감각을 느끼게 하는 것은 힘들겠지만, 물건을 집거나 몇 가지 움직임을 마음먹은 대로 할 수 있다면 절단 장애인들에게는 큰 도움이 될 것이다. 3D프린팅 기술의 발달로 저렴한 의수개발이 가능해졌으며, 이러한 추세에 맞추어 개인맞춤형 의수를 비슷한 가격에 개발할 수 있다면 활용도 및 보급률이 훨씬 높아질 것이다. 본 논문에서는 3D프린팅을 이용하여 사용자 맞춤형 의수를 개발하는 방법에 대해 기술한다. 이를 위해 의수 외형 모델링의 변형수치를 가변값으로 추출하고, 의수 동작을 제어하는 기능을 소프트웨어 디자인 패턴을 이용하여 설계한다. 이를 통해 의수를 필요로 하는 사람들이 각자 원하는 자신만의 의수를 빠르고 저렴한 가격에 갖출 수 있도록 한다.

Effect of Prior Muscle Contraction or Passive Stretching on Eccentric-Induced Muscle Damage

  • Choi, Seung-Jun
    • PNF and Movement
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    • 제17권3호
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    • pp.487-497
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    • 2019
  • Purpose: This tutorial review investigated the effect of prior fatigue and passive stretches on eccentric contraction-induced muscle injuries, as well as the underlying mechanisms of eccentric contraction-related injuries. Methods: Contraction-induced muscle damage is the most common disabling problem in sports and routines. The mechanisms underlying the pathology and prevention of muscle damage lessened by prior fatigue or stretches are critical in assessing musculoskeletal injuries. Even though there are treatments to reduce eccentric contraction-induced muscle injuries, fatigue negatively influences them. Therefore, we reviewed previous studies on eccentric contraction-induced muscle injuries with prior treatments using the MEDLINE and PubMed databases. Results: Prior passive stretching had a preventative and therapeutic effect, but prior lengthening contractions did not. On the other hand, prior isometric contractions involving relatively small forces may not provide a sufficient stimulus to induce protection. As a result, high force isometric contractions may be necessary. The studies supported the positive effects of prior fatigue, concluding that it was a factor in determining the amount of damage caused by eccentric exercise. This was due to a reduction in force and increased temperature. Studies that did not support the positive effects of prior fatigue concluded that a shift in optimal length to a longer length and reduced energy absorption during lengthening are evidence that fatigue is not related to muscle injuries induced by lengthening. Conclusion: The variability of the experiment models, conditions, muscles, and treatment methods make it necessary to interpret the conditions of previous studies carefully and draw conclusions without making direct comparisons. Thus, additional studies should be carefully conducted to investigate the positive effect of fatigue on lengthening.

수도권의 사업체 규모에 따른 화물발생 예측 방법론 연구 (A Study on the Method of Freight Generation Estimation according to Company Size in Seoul Metropolitan Area)

  • 박상철;최창호
    • 한국항해항만학회지
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    • 제29권5호
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    • pp.431-437
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    • 2005
  • 화물발생 예측을 위해 주로 이용된 방법은 교통존을 중심으로 한 공간단위의 접근기법이다. 또한 연구사례에 따라 물동량 전수화 방법에 차이가 있고 모형에 포함된 변수가 다른 경우가 많아 일관된 화물발생 예측에 어려움이 있다. 본 연구에서 시도한 물동량 단위 예측기법은 개별 사업체를 대상으로 유출${\cdot}$입하는 화물 물동량과 종업원수, 매출액, 연면적, 부지면적 등 사업체의 특성을 이용하여 사업체 단위로 화물발생을 예측하는 것으로 공간단위 접근기법보다 간편하고 다른 지역에 적용이 가능한 장점이 있다. 연구의 대상은 수도권에 소재한 사업체이며 매출액을 설명변수로 선정하여 회귀식을 추정하고 모형의 적합성을 검증하였다. 회귀모형의 형태는 지수형으로 매출액이 증가함에 따라 화물발생의 규모도 커지는 특징을 갖는다. 본 연구는 교통 존 단위가 아닌 사업체 단위로 화물발생을 예측하는 보다 미시적인 연구방법을 개발함에 의의가 있다.