• Title/Summary/Keyword: analysis parameters

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Determination of Dynamic Parameters of Continuous Beam Using Morlet Wavelet (Morlet웨이블렛을 이용한 연속보의 동적 파라메터 추정)

  • 박종열;박형기;김규학
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2002.03a
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    • pp.143-150
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    • 2002
  • This paper presents the application of continuous wavelet transform for determination of dynamic parameters of continuous beam subjected to moving load. Morlet wavelet is used as mother wavelet in wavelet transform. Dynamic parameters are estimated from the magnitudes and arguments of the wavelet coefficients obtained by wavelet transforming the response time histories of joints on the beam. This study shows that the estimated parameters such as natural frequencies, dmping ratios and mode shapes are to be well-compared with those of the finite element analysis.

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A Study on Design Parameters to Improve Load Capacity of Spiral Grooved Thrust Bearing (스파이럴 그루브 스러스트 베어링의 부하용량 향상을 위한 설계 변수에 대한 연구)

  • 강지훈;김경웅
    • Tribology and Lubricants
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    • v.18 no.3
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    • pp.181-186
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    • 2002
  • A numerical analysis is undertaken to show the influence of bearing design parameters on the load capacity of air lubricated spiral grooved thrust bearing. The governing equation derived from the mass balance is solved by the finite difference method. Optimal values for various design parameters are obtained to maximize the load capacity. The design parameters are the groove angle, the groove width ratio, the groove height ratio, and the seal ratio.

Stochastic Daily Weather Generations for Ungaged Stations (기상자료 미계측 지역의 추계학적 기상발생모형)

  • 강문성;박승우;진영민
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.40 no.1
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    • pp.57-67
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    • 1998
  • A stochastic weather generator which simulate daily precipitation, maximum and minimum daily temperature, relative humidity was developed. The model parameters were estimated using stochastic characteristics analysis of historical data of 71 weather stations. Spatial variations of the parameters for the country were also analyzed. Model parameters of ungauged Sites were determined from parameters of adjacent weather stations using inverse distance method. The model was verified on Suwon and Ulsan weather stations and showed good agreement between simulated and observed data.

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A Study on Design Parameters to Improve Load Capacity of Spiral Grooved Thrust Bearing (스파이럴 그루브 형상의 스러스트 베어링의 부하용량 향상을 위한 설계 변수에 대한 연구)

  • 강지훈;김경웅
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2001.06a
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    • pp.257-262
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    • 2001
  • A numerical analysis is undertaken to show tile influence of bearing design parameters on tile load capacity of air lubricated spiral grooved thrust bearing. The governing equation derived from the mass balance is solved by the finite difference method. Optimal values for various design parameters are obtained to maximize the load capacity. The design parameters are the groove angle, the groove width ratio, the groove height ratio, arid the seal ratio.

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An analysis of gait characteristic parameters for the Korean normal adults (한국인의 보행특성에 관한 연구)

  • 황규성;정민근;이동춘
    • Journal of the Ergonomics Society of Korea
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    • v.10 no.2
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    • pp.15-22
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    • 1991
  • Gait analysis techniques are widely used in Europe and the United States to investigate the loosening problems of total joint implantation and to improve the technologies in designing prosthetic devices. In Korea, however, the gait data are rarely found. Recently, as the standards of living become improved, the number of lower extremity operation patients increase rapidly. Therefore, a study on the gait characteristic parameters for Koreans is of great importance. In this study, time-distance gait parameters and ground reaction fore are analyzed using a FOANAS system developed by Pohang Institute of Science and technology (POSTECH). Gait parameters of Korean normal adults were preceded and comparisons were made for the distinction of sex and age.

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A Study for Design of Reinforced Concrete Pier Based on Virtual Model (Virtual Modeling 기반의 철근 콘크리트 교각 설계에 관한 연구)

  • Lee, Heon-Min;Park, Jae-Geun;Kim, Min-Hee;Choi, Jung-Ho;Shin, Hyun-Mock
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2008.04a
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    • pp.96-99
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    • 2008
  • When the design modification is occurred, at present, design process based on 2-D spend more time and effort than that based on 3-D to modify related structural details. To improve and develop these processes, therefore, the design possibility of civil structures based on virtual model of 3-D must be investigated. We designed reinforced concrete pier of 3-D model, containing parameters. The parameters was defined as structural details like area of the section, reinforcement specification for design modification and structural analysis. In this paper, we researched about the processes modeling of reinforced concrete bridge pier based on parameters, the extracting data from the virtual model of 3-D, and the reflection of data to virtual model throughout structural analysis.

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Sensitivity Analysis of Design Parameters for Reduction of Cogging Torque in Brushless DC Motors used for Automobile Part (자동차 부품용 BLDC 모터 내의 코깅 토크 저감을 위한 설계 변수의 민감도 해석)

  • 황상문
    • Transactions of the Korean Society of Automotive Engineers
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    • v.6 no.2
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    • pp.235-243
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    • 1998
  • For motor operation at low speeds and loads, torque pulsation by the cogging torque is often a source of vibration and control difficulty. In this paper, the magnetic field of a motor is calculated by finite element method. The periodic cogging torque is determined using Maxwell stress method and time stepping method, and then decomposed using fourier series expansion, The purpose of this paper is to characterize design parameters on the cogging torque and to design a permanent magnet motor with a cogging torque less vulnerable to vibration, without sacrificing the motor performance. The design parameters include stator slot width, permanent magnet slot width, airgap length and magnetization direction. A new design with a less populated frequency spectrum of the cogging torque is proposed after characterizing individual effect of design parameters. Magnet pole edge shaping, by gradually increasing the cogging torque with reduced higher harmonics.

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Gait Analysis of Parkinson's Disease Patients (파킨슨 질환 환자의 보행분석)

  • You, Jae-Eung;Choi, Byung-Ok;Jung, Seok
    • The Journal of Korean Physical Therapy
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    • v.17 no.4
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    • pp.569-574
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    • 2005
  • The purposes of this study were to present the basic reference data of age and specipic gait parameters for Parkinson's disease patients. The basic gait parameters were extracted from 20 patients of parkinson's disease and 20 healthy control subjects using VICON 512 Motion Analyzer. The temporal gait parameters and kinematic parameters is data of Parkinson' s Disease Patients. The results were as follows: (1) In patients' group, cadence, walking velocity were less than control group (p<.05). (2) In patients' group, maximum flexion of hip, maximum adduction of hip and maximum flexion of the knee were less than control group (p<.05). (3) In patients' group, maximum varus of the knee were more than control group (p<.05).

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Reinforcement Efficiency of Concrete Compressive Members Confined with Carbon Fiber Sheet (탄소섬유쉬트로 횡보강된 콘크리트 압축부재의 보강성능에 관한 연구)

  • 성시문;강상용;임재형;이원호
    • Proceedings of the Korea Concrete Institute Conference
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    • 2002.05a
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    • pp.835-840
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    • 2002
  • The purpose of this study is to analyze the reinforcement effect of the RC compressive member confined with carbon fiber sheets and to suggest better transverse confinement coefficient(k$_1$) than one's in the existing analysis equations. Showing amounts of CPS in terms of ratio of transverse reinforcement to cross-section, it comes to be possible to calculate the objective and quantitative reinforcement amounts and to estimate the overlapping length of CFS that can influence on all its confinement effect. The previous parameters were compared using the existing experimental test data, then analyzed for the merits and demerits of existing parameters through the coefficient of correlation(R). The proposed parameters were derived in such a way that established parameters and their combination were obtained from the analytical study and then determined by regression analysis using the previous test data.

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Proposal of pulse parameter useful for pulse wave analysis in oriental medicine: Preliminary study on floating and sinking pulses (통계분석을 통한 한의 맥진에 유용한 파라미터 도출: 부침맥을 중심으로 한 예비연구)

  • Lee, Jeon;Lee, Yu-Jung;Lee, Hae-Jung;Choi, Eun-Ji;Kim, Jong-Yeol
    • Proceedings of the KIEE Conference
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    • 2006.10c
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    • pp.244-246
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    • 2006
  • In this study, we search some parameters well-related to floating-sinking pulse by statistical analysis, because these pulses are frequently used in clinic. Pulse signals were acquired by 3D pulse analyzer and 30 subjects consist of 15 people diagnosed as floating pulse and 15 people diagnosed as sinking pulse by oriental doctors who have over 5 years clinical experience. Then, we made a representative beat template for each subject and, through a peak detection algorithm, we calculated several pulse parameters. To find the parameters related to floating-sinking pulse, we performed statistical testing with 17 parameters through the independence sampling, t-test. As a result, there is the biggest difference between pressure, the maximum pulse pressure, diastolic area(Ad) and float-sink data. (p < .05).

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