• Title/Summary/Keyword: transformed time scale

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A Study on the Analysis of Area for the Planning of Diagnostic Imaging Department (영상의학부 공간계획을 위한 면적분석에 관한 연구)

  • Youn, Woo-Young;Chai, Choul-Gyun
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.12 no.1
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    • pp.61-69
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    • 2006
  • The Diagnostic Imagining Department essentially needs to be transformed by the plan of the room and the medical equipment which should be improved according to a rapid development in technology. And the room should be considered the scale and composition an the time of planning. Because this part is often influenced in a specific character of imaging equipment in the room. The researches on the scale and composition of Diagnostic Imaging Department were the main part in 1980's but after 1990's this kind of researches have not been enough. So this study has an intention of proposing basic data which is used in planning the Diagnostic Imaging Department by analyzing the actual condition of the area organization in general hospital.

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A Reduction Algorithm of Computational Amount using Adjustment the Not Uniform Interval and Distribution Characteristic of LSP (불균등 간격조절과 선형 스펙트럼 쌍 분포특성을 이용한 계산량 단축 알고리즘)

  • Ju, Sang-Gyu
    • Proceedings of the KAIS Fall Conference
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    • 2010.05a
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    • pp.261-264
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    • 2010
  • Fast algorithm is proposed by using mel scale and the distribution characteristic of LSP parameters, and is to reduce the computational amount. Computational amount means the calculating times of transformation from LPC coefficients to LSP parameters. Among conventional methods, the real root method is considerably simpler than other, but neverthless, it still suffer from its indeterministic computational time. Because the root searching is processed sequentially in frequency region. In this paper, the searching interval is arranged by using mel scale but not it is uniform and searching order is arranged by the distribution characteristic of LSP parameters that is most LSP papameters are occured in specific frequency region. In experimental results, computational amount of the proposed algorithm is reduced about 48.95% in average, but the transformed LSP parameters of the proposed method were the same as those of real root method.

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A Study on the Frequency Scaling Methods Using LSP Parameters Distribution Characteristics (LSP 파라미터 분포특성을 이용한 주파수대역 조절법에 관한 연구)

  • 민소연;배명진
    • The Journal of the Acoustical Society of Korea
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    • v.21 no.3
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    • pp.304-309
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    • 2002
  • We propose the computation reduction method of real root method that is mainly used in the CELP (Code Excited Linear Prediction) vocoder. The real root method is that if polynomial equations have the real roots, we are able to find those and transform them into LSP. However, this method takes much time to compute, because the root searching is processed sequentially in frequency region. In this paper, to reduce the computation time of real root, we compare the real root method with two methods. In first method, we use the mal scale of searching frequency region that is linear below 1 kHz and logarithmic above. In second method, The searching frequency region and searching interval are ordered by each coefficient's distribution. In order to compare real root method with proposed methods, we measured the following two. First, we compared the position of transformed LSP (Line Spectrum Pairs) parameters in the proposed methods with these of real root method. Second, we measured how long computation time is reduced. The experimental results of both methods that the searching time was reduced by about 47% in average without the change of LSP parameters.

A Study on an Input-Output Controller Based on the Time-Scale Properties of an Underwater Vehicle Dynamics (수중 운동체의 운동 특성을 고려한 입/출력 제어기 구성에 관한 고찰)

  • Jo, Gyung-Nam;Seo, Dong-C.;Choi, Hang-S.
    • Journal of the Society of Naval Architects of Korea
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    • v.45 no.5
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    • pp.469-476
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    • 2008
  • In this paper, it is shown that an input-output (I/O) feedback linearized controller can be designed rationally by utilizing the time-scale properties of heave and pitch for an underwater vehicle. It is assumed that the dynamics of the vehicle is restricted to the vertical plane. An output-feedback control is designed, which stabilizes steady cruising paths. It is shown that the vehicle dynamics with acceleration as output becomes minimum phase. The dynamics can be transformed into a reduced system through a kind of partial linearization and singular perturbation technique. The reduced system is not only minimum phase but also exactly I/O linearizable via feedback. The I/O dynamic characteristics of the heave and pitch modes can be made linear and decoupled. Furthermore it becomes independent of cruising condition such as vehicle velocity. This study may help for designing autopilot systems for underwater vehicles.

Minimum-Time Trajectory Planning for a Robot Manipulator amid Obstacles (로봇팔의 장애물 중에서의 시간 최소화 궤도 계획)

  • 박종근
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.1
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    • pp.78-86
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    • 1998
  • This paper presents a numerical method of the minimum-time trajectory planning for a robot manipulator amid obstacles. Each joint displacement is represented by the linear combination of the finite-term quintic B-splines which are the known functions of the path parameter. The time is represented by the linear function of the same path parameter. Since the geometric path is not fixed and the time is linear to the path parameter, the coefficients of the splines and the time-scale factor span a finite-dimensional vector space, a point in which uniquely represents the manipulator motion. The displacement, the velocity and the acceleration conditions at the starting and the goal positions are transformed into the linear equality constraints on the coefficients of the splines, which reduce the dimension of the vector space. The optimization is performed in the reduced vector space using nonlinear programming. The total moving time is the main performance index which should be minimized. The constraints on the actuator forces and that of the obstacle-avoidance, together with sufficiently large weighting coefficients, are included in the augmented performance index. In the numerical implementation, the minimum-time motion is obtained for a planar 3-1ink manipulator amid several rectangular obstacles without simplifying any dynamic or geometric models.

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A Study on the Reduction of LSP(Line Spectrum Pair) Transformation Time in Speech Coder for CDMA Digital Cellular System (이동통신용 음성부호화기에서의 LSP 계산시간 감소에 관한 연구)

  • Min, So-Yeon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.8 no.3
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    • pp.563-568
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    • 2007
  • We propose the computation reduction method of real root method that is used in the EVRC(Enhanced Variable Rate Codec) system. The real root method is that if polynomial equations have the real roots, we are able to find those and transform them into LSP. However, this method takes much time to compute, because the root searching is processed sequentially in frequency region. But, the important characteristic of LSP is that most of coefficients are occurred in specific frequency region. So, to reduce the computation time of real root, we used the met scale that is linear below 1kHz and logarithmic above. In order to compare real root method with proposed method, we measured the following two. First, we compared the position of transformed LSP(Line Spectrum Pairs) parameters in the proposed method with these of real root method. Second, we measured how long computation time is reduced. The experimental result is that the searching time was reduced by about 48% in average without the change of LSP parameters.

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A Study on the Mixing Characteristics in Complex Turbulent Flow by a Laser Induced Fluorescence Method (레이저 형광여기법(LIF)를 이용한 복잡 난류유동장의 혼합특성에 관한 연구)

  • Kim, Kyung-Chun;Jeong, Eun-Ho
    • Proceedings of the KSME Conference
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    • 2001.06e
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    • pp.542-547
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    • 2001
  • A non-intrusive Planar Laser-Induced Fluorescence(PLIF) technique was applied to study the turbulent mixing process in a Rushton turbine reactor. Instantaneous and ensemble averaged concentration fields are obtained by measuring the fluorescence intensity of Rhodamine B tracer excited by a thin Nd:Yag laser sheet illuminating the whole center plane of the stirred tank. The gray level images captured by a 14-bit cooled CCD camera can be transformed to the local concentration values using a calibration matrix. The dye injection point was selected at the tank wall with three quarter height (3/4H) from the tank bottom to observe the mixing characteristics in upper bulk flow region. There exist distinct two time scales: the rapid decay of mean concentration in each region after the dye infusion reflects the large scale mixing while the followed slow decay reveals the small scale mixing. The temporal change of concentration probability functions conjectures the two sequential processes in the batch type mixing. An inactive column of water existed above the impeller disk, in which the fluid rotates with the shaft but is isolated from the mean bulk flow.

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A Study on the Mixing Characteristics in a Rushton Turbine Reactor by a Laser Induced Fluorescence Method (레이저 형광여기법(LIF)를 이용한 러쉬톤 터빈 교반기의 혼합특성에 관한 연구)

  • Jeong, Eun-Ho;Kim, Gyeong-Cheon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.26 no.8
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    • pp.1145-1152
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    • 2002
  • A non-intrusive Planar Laser-Induced Fluorescence(PLIF) technique was applied to study the turbulent mixing process in a Rushton turbine reactor. Instantaneous and ensemble averaged concentration fields was obtained by measuring the fluorescence intensity of Rhodamine B tracer excited by a thin Nd:Yag laser sheet illuminating the whole center plane of the stirred tank. The gray level images captured by a 14-bit cooled CCD camera could be transformed to the local concentration values using a calibration matrix. The dye injection point was selected at the tank wall with three quarter. height (3/4H) from the tank bottom to observe the mixing characteristics in upper bulk flow region. There exist distinct two time scales: the rapid decay of mean concentration after the dye infusion reflects the large scale turbulent mixing while the fellowed slow decay reveals the small scale molecular mixing. The temporal change of concentration variance field conjectures the two sequential processes for the batch type mixing. An inactive column of water is existed above the impeller disk, in which the fluid rotates with the shaft but is isolated from the mean bulk flow.

The Study on permeability enhancement in smear zone using electro-osmotic pressure (전기 삼투압을 이용한 교란영역의 투수성 개선에 관한 연구)

  • Ahn, Byung-Wook;Noh, Hee-Jeon;Kim, Hyun-Ki;Cho, Nam-Jun
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.03a
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    • pp.435-441
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    • 2008
  • More time is required for consolidating soft clay when its hydraulic conductivity around the vertical drains is reduced by soil disturbance. One of the methods to be proposed to solve such problem is the electro-osmotic flow application. This study presents the experimental results of model tests using a modified oedometer and a large-scale cylinder with a sand drain. Results show that the development of negative excessive pore water pressure due to the DC electrical field in saturated clay can be transformed to additional loads causing more consolidation settlement.

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A Note on the Efficiency Based Reliability Measures for Heterogeneous Populations

  • Cha, Ji-Hwan
    • Communications for Statistical Applications and Methods
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    • v.18 no.2
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    • pp.201-211
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    • 2011
  • In many cases, populations in the real world are composed of different subpopulations. Furthermore, in addition to the heterogeneity in the lifetimes of items, there also could be the heterogeneity in the efficiency or performance of items. In this case, the reliability measures should be defined in a different way. In this article, we consider the mixture of stochastically ordered subpopulations. Efficiency based reliability measures are defined when the performance of items in the subpopulations has different levels. Discrete and continuous mixing models are studied. The concept of the association between the lifetime and the performance of items in subpopulations is defined. It is shown that the consideration of efficiency can change the shape of the mixture failure rate dramatically especially when the lifetime and the performance of items in subpopulations are negatively associated. Furthermore, the modelling method proposed in this paper is applied to the case when the stress levels of the operating environment of items are different.