• 제목/요약/키워드: Maximum variation

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Study of quake wavelength of dynamic movement with posture

  • Kim, Jeong-lae;Hwang, Kyu-sung
    • International journal of advanced smart convergence
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    • v.4 no.1
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    • pp.99-103
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    • 2015
  • Quake wavelength technique was designed of the sway by the body. There was presented a concept of the dangle wavelength by twisting condition of posture. We compared to the twisting condition for an average variation and maximum variation with the movement. There was used a combination system and correlation system of the posture. Their correlation signal was presented a control data by the dynamic movement. The quake wavelength system was to be formation of activity aspects by posture. The correlation of wavelength technique was applied to the a little action of posture variation signal. Quake wavelength by the dynamic movement was determined to a variation of vision condition of the $Vi-{\alpha}_{AVG}$ with $(-1.27){\pm}(-0.34)$ units, that vestibular condition of the $Ve-{\alpha}_{AVG}$ with $(-0.49){\pm}(-0.4)$ units, that somatosensory condition of the $So-{\alpha}_{AVG}$ with $0.037{\pm}0.269$ units, that CNS condition of the $C-{\alpha}_{AVG}$ with $(-0.049){\pm}0.015$ units. As the study of the quake wavelength technique was depended on the action system of body movement that a maximum and averag values was used a movement of combination data. The system was required an action signal for the form of actual signal on the basis of a little movement condition in the body. The human action systemwas compared to maximum and average from the movement derived the body. Therefore, their system was controlled to evaluate posture condition for the body correlation.

The Variation of Channel Bed by Location of Pier near 90° Channel Junction (90° 합류부를 지닌 수로에서 교각 위치에 따른 하상변동)

  • Choi, Gye-Woon;Kim, Young-Kyu;Kim, Gee-Hyoung
    • Journal of Korea Water Resources Association
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    • v.37 no.9
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    • pp.781-787
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    • 2004
  • The variation of channel bed which shows the complex hydraulic characteristics at channel junction was investigated by variation of discharge ratio and location of pier. As discharge ratio increase, the depth and width of erosion region become bigger to point of 63% of channel width in case of 1:0.5 discharge ratio. It was observed that the maximum scour depth at the point of 0.5 times of the channel width in the channel junction as 2.5 times bigger than straight channel. It means that the maximum scour depth at the channel junction is 2 times greater than by experimental formulas which are widely used in practical engineering, location of pier should be determined when it is installed in channel junction.

Characteristics of nocturnal maximum ozone and meteorological relevance in Pusan coastal area (부산 연안역의 야간 고농도 오존 발생 특성과 기상학적 관련성)

  • 전병일
    • Journal of Environmental Science International
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    • v.8 no.3
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    • pp.287-292
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    • 1999
  • This study was performed to investigate the characteristics of nocturnal maxiumu ozone occurrence and the meteorological relevance using to hourly ozone data and meteorological data for 1995~1996 in Pusan coastal area. Kwangbokdong showed the highest occurrence of nocturnal maximum ozone as 36.9%, and Deokcheondong showed the lowest occurrence(9.2%) for research period in Pusan. The occurrence rates of nocturnal maximum ozone concentration were decreased toward land area. The low maximum temperature, high minimum temperature, low diurnal range, high relative humidity, high wind speed, high could amount, low sunshine and low radiation were closely related to the main meteorological characteristics occuring the nocturnal maximum concnetration of ozone. It was shown that normal daily variation of ozone concentration by strong photochemical reaction at the before day of nocturnal maximum ozone. The concnetration of nocturnal maximum ozone were occured by entrainment of ozone from the upper layer of developed mixing layer. There are no ozone sources near the ground at night, so that the nighttime ozone should be entrained from the upper layer by forced convection.

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A Study on the Optimal Frame Design of Armscye Circumference (겨드랑둘레선의 최적 프레임 생성에 관한 연구)

  • Park, Sun-Mi;Choi, Kueng-Mi;Nam, Yun-Ja;Ryu, Young-Sil;Jun, Jung-Ill
    • Fashion & Textile Research Journal
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    • v.11 no.5
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    • pp.788-798
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    • 2009
  • This study aims to develop a highly reproducible, optimal frame design algorithm using variations in the curvature of armscye circumference, which will provide the basics for remodeling the 3D human body shape with the concept of reverse design used to develop total contents for the apparel industry. 1. The results of the experiment proved that ratio value was significantly efficient than absolute value of curvature variation to extract feature points in the armscye circumference 2. For the shoulder(1st and 2nd quadrant) and front armhole(3rd quadrant) parts of the armscye circumference, frame remodeling with the positive point of inflection led to the completion of a highly reproducible frame. 3. Similarly, even for the rear armhole part(4th quadrant) in the armscye circumference, it was found that frame remodeling using the positive maximum point of inflection resulted in highly reproducible body shape with the maximum point of inflection situated within the range of split angles $305^{\circ}{\sim}330^{\circ}$, while frame remodeling using simultaneously the two largest points of inflection including maximum point of inflection led to highly reproducible body shape with the maximum point of inflection out of the range $305^{\circ}{\sim}330^{\circ}$. 4. Based upon the optimal frame design algorithm developed in this study, section-specific feature points in the armscye circumference were extracted depending on the rate of curvature variation and remodeling with spline curves was conducted. The results indicate a remarkably high reproducibility(98.6%) and suggest that the algorithm developed in this study is suitable for human body modeling.

Maximum-Efficiency Tracking Scheme for Piezoelectric-Transformer Inverter with Dimming Control

  • Nakashima Satoshi;Ogasawara Hiroshi;Kakehashi Hidenori;Ninomiya Tamotsu
    • Proceedings of the KIPE Conference
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    • 2001.10a
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    • pp.7-10
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    • 2001
  • This paper provides a solution for the problem of efficiency decrease caused by load variation. A novel control scheme of tracking the PT's operation frequency for the maximum efficiency is proposed. As a result, a high efficiency over $80\%$ has been achieved even under the output-current decrease down to $10\%$ of the full load current.

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A COMPARATIVE EVALUATION OF THE ESTIMATORS OF THE 2-PARAMETER GENERALIZED PARETO DISTRIBUTION

  • Singh, V.P.;Ahmad, M.;Sherif, M.M.
    • Water Engineering Research
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    • v.4 no.3
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    • pp.155-173
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    • 2003
  • Parameters and quantiles of the 2-parameter generalized Pareto distribution were estimated using the methods of regular moments, modified moments, probability weighted moments, linear moments, maximum likelihood, and entropy for Monte Carlo-generated samples. The performance of these seven estimators was statistically compared, with the objective of identifying the most robust estimator. It was found that in general the methods of probability-weighted moments and L-moments performed better than the methods of maximum likelihood estimation, moments and entropy, especially for smaller values of the coefficient of variation and probability of exceedance.

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Analysis of Long-Term Riverbed-Level and Flood Stage Variation due to Water Gate Operation of Multi-functional Weirs at Geum River (다기능보의 수문운영에 따른 금강의 장기하상변동 및 홍수위변화 분석)

  • Jeong, Anchul;Jung, Kwansue
    • Journal of Korea Water Resources Association
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    • v.48 no.5
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    • pp.379-391
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    • 2015
  • Multi-functional weirs has been installed in four rivers are hydraulic structures across the river. The structures were divided into movable and fixed weirs. Hence, riverbed-level variation and sediment transport can be varied due to water gate operation. In this study, the long-term riverbed-level variation of Geum river basin due to water gate operation of multi-functional weirs was studied. Result of this study shows that the variation of thalweg elevation was greater than the variation of annual average riverbed elevation due to multi-functional weirs construction and water gate operation. Maximum riverbed degradation of thalweg elevation that occurred was 2.79m and riverbed aggradation was 1.90m. Maximum riverbed degradation of the annual average riverbed elevation that occurred was 2.16m and riverbed aggradation was 1.24m. Analysis result of flood stage by the variation of riverbed-level shows that flood stages were increased in majorities area. The maximum increase in the value of flood stage was 2.23m. For this reason, flood stages can be greater than the freeboard of the levees. Therefore, we should consider the water gate operation of multi-functional weirs when planning and managing sediment in the river. We are expecting to use the result of this study in river planning for river management and selecting the river regime.

Origin of the Initial Permeability of Manganese-Zinc Ferrite Polycrytals (Mn-Zn 페라이트 다결정의 조성에 따른 투자율의 변화 기구)

  • 변순천;제해준;고경현;홍국선
    • Journal of the Korean Ceramic Society
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    • v.34 no.4
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    • pp.351-356
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    • 1997
  • The origin of the variation of initial permeability in manganese-zinc ferrite polycrystals with a content of hematite was investigated. Initial permeability showed maximum with hematite content while there was no significant change in microstructure. Saturation magnetization increased with hematite content. So the variation of initial permeability was not explained on the basis of microstructural change or saturation magnetization. Temperature dependence of initial permeability revealed magnetocrystalline anisotropy was the origin of the variation of initial permeability. The change in magnetocrystalline anisotropy was ascribed to the variation in ferrous ion concentration. Therefore the variation of initial permeability in manganese-zinc ferrite polycrystals with a content of hematite was due to ferrous ion concentration via magnetocrystalline anisotropy.

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A Study on the Variation of Optical Fiber Splicing Loss due to Environment (광섬유 접속부의 환경 변화에 따른 손실변화 연구)

  • Kim Young-Ho;Yoo Kang-Hee
    • 한국정보통신설비학회:학술대회논문집
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    • 2006.08a
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    • pp.105-110
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    • 2006
  • The most sensitive part of the installed optical cable is the optical loss variation of the splicing point according to the environmental changes. This paper presents the details of the experimental results of the external environmental changes on optical loss, such as bending, temperature variation, temperature variation after water osmosis and variation. Through the bending test of optical fiber, rapid increase of optical loss was measured within the diameter of 30mm. The result of optical loss variation within the temperature range of $-30^{\circ}C{\sim}60^{\circ}C$ is less than 0.02dB. It was confirmed that the maximum optical loss increased up to 0.2dB in case of water osmosis within the temperature range of $-40^{\circ}C{\sim}80^{\circ}C$. There is small optical loss variation of 0.01dB under the 1mm vibration test. The experimental results of this paper can be used as the reference data for the design of the optical fiber cable splicing enclosure to protect the optical loss variation due to environmental changes.

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Performance of PI Controller for Maximum Power Extraction of a Grid-Connected Wind Energy Conversion System (계통연계 풍력발전 시스템의 최대출력 제어를 위한 PI 제어기의 성능 분석)

  • No, Gyeong-Su;Ryu, Haeng-Su
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.51 no.8
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    • pp.391-397
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    • 2002
  • This paper presents a modeling and simulation of a PI controller for maximum power extraction of a grid-connected wind energy conversion system with a link of a rectifier and an inverter. It discusses the maximum power control algorithm fnr a wind turbine and proposes, in a graphical form, the relationships of wind turbine output, rotor speed, power coefficient, tip-speed ratio with wind speed when the wind turbine is operated under the maximum power control. The control objective is to always extract maximum power from wind and transfer the power to the utility by controlling both the Pitch angle of the wind turbine blades and the inverter firing angle. Pitch control method is mechanically complicated, but the control performance is better than that of the stall regulation method. The simulation results performed on MATLAB will show the variation of generator's rotor angle and rotor speed, pitch angle, and generator output.