• Title/Summary/Keyword: S-parameters

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Additional Traffic Descriptors for Associatiove QoS Parameters in a Multimedia Service (멀티미디어 서비스에서 연관 QoS 지원을 위한 트래픽 기술자)

  • 김지영;이상목최봉근이상홍
    • Proceedings of the IEEK Conference
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    • 1998.06a
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    • pp.86-89
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    • 1998
  • Multiple types of information in a multimedia service are delivered though multiple virtual connections on ATM network, while each virtual connection may be controlled independently. A multimedia service requires an associative relationship among multiple information streams to provide required harmonization. There may be required additional traffic descriptors to guarantee the required harmonization among multiple information streams in a multimedia service. For buffering of large bandwidth information stream(e.g., video), extremely large buffer size is necessary, but this approach should not be efficient way to compensate a severely delayed cells/blocks experienced at network. The best way to solve this problem will be minimization of relative-delayed-transfer of cells/blocks to application processes through ATM network control. To minimize a delayed transfer the mapping between relative delay parameter(i.e., associative Group QoS parameters) and per-VC traffic descriptor will be necessary. This paper is present additional functions and parameters to interpret the mapping between relative delay parameters(i.e., associative Group QoS parameters) and per-VC traffic descriptors in ATM API for multimedia application services.

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Parameter Extraction and Simulation in order to Manufacture Ready-made Ear Shell for CIC Type Hearing Aids (CIC형 보청기용 범용 이어쉘 제작을 위한 파라미터 추출 및 시뮬레이션)

  • U, Erdenebayar.;Jeon, Y.Y.;Park, G.S.;Song, Y.R.;Lee, S.M.
    • Journal of Biomedical Engineering Research
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    • v.31 no.4
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    • pp.321-327
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    • 2010
  • Most of the ear shells of hearing aids are manufactured manually, and it is one of the reasons that the cost of the custom-made hearing aids can be increased. Thus it is required to manufacture the ready-made ear shell for the purpose of easy manufacturing and decrease in cost. In this study, we extract parameters in order to manufacture the ready-made ear shell for CIC type hearing aids and simulate to reconstruct the ear shell using the extracted parameters. To parameter extraction, we set up the eleven parameters for the ready-made ear shell based on anatomical characteristics of the ear canal, and we found values of the parameters from twenty-one impressions in their 20s and twelve impressions in their 60s using aperture detection and feature detection algorithms. Classifying the parameters by size, we also determine the parameters of ready-made ear shell into three types for people in their 20s and two types for people in their 60s. Each ready-made ear shell was simulated to reconstruct using figured parameters, and evaluated the rate of agreement with unused impressions for setting parameters. To evaluate the ready-made ear shell, we calculate the volume ratio and intersection between of the each impression and ready-made ear shell, and the intersection ratio using the intersection volume and ready-made ear shell volume. As a result, the volume ratio was about 70%, and volume match ratio was also up to 70%. It means that the ready-made ear shell we simulated is the significantly matched to impression.

Small signal model and parameter extraction of SOI MOSFET's (SOI MOSFET's의 소신호 등가 모델과 변수 추출)

  • Lee, Byung-Jin;Park, Sung-Wook;Ohm, Woo-Yong
    • 전자공학회논문지 IE
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    • v.44 no.2
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    • pp.1-7
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    • 2007
  • The increasing high frequency capabilities of CMOS have resulted in increased RF and analog design in CMOS. Design of RF and analog circuits depends critically on device S-parameter characteristics, magnitude of real and imaginary components and their behavior as a function of frequency. Utilization of scaled high performance CMOS technologies poses challenges as concerns for reliability degradation mechanisms increase. It is important to understand and quantify the effects of the reliability degradation mechanisms on the S-parameters and in turn on small signal model parameters. Various physical effects influencing small-signal parameters, especially the transconductance and capacitances and their degradation dependence, are discussed in detail. The measured S-parameters of H-gate and T-gate devices in a frequency range from 0.5GHz to 40GHz. All intrinsic and extrinsic parameters are extracted from S-parameters measurements at a single bias point in saturation. In this paper we discuss the analysis of the small signal equivalent circuits of RF SOI MOSFET's verificated for the purpose of exacting the change of parameter of small signal equivalent model followed by device flame.

Parameter Extraction for BSIM3v3 RF Macro Model (BSIM3v3 RF Macro Model의 파라미터 추출)

  • Choi, Mun-Sung;Lee, Yong-Taek;Kim, Joung-Hyck;Lee, Seong-Hearn
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.671-674
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    • 2005
  • The series parasitic resistances ($R_s$, $R_g$, $R_d$, $R_{sub}$) of BSIM3v3 RF MOSFET macro model were directly extracted from measured S-parameters in the GHz region by using simple 2-port parameter equations. Also, overlap capacitance and junction capacitance parameters were extracted by tuning $S_{11}$, $S_{12}$, and $S_{22}$ respectively while DC-parameters and all parasitic resistances are fixed at previously extracted values. These data are verified to be accurate by observing good correspondence between modeled and measured S-parameters up to 10GHz.

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Optimal Parameters Estimation of Diffusion-Analogy Geomorphologic Instantaneous Unit Hydrograph Model (확산-유추 지형학적 순간단위도 모형의 최적매개변수 추정)

  • Kim, Joo-Cheol;Choi, Yong-Joon
    • Journal of Wetlands Research
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    • v.13 no.3
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    • pp.385-394
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    • 2011
  • In this study, optimal parameters of diffusion-analogy GIUH were calculated by separating channel and hillslope from drainage structures in the basin. Parameters of the model were composed of channel and hillslope, each velocity($u_c$, $u_h$) and diffusion coefficient($D_c$, $D_h$). Tanbu subwatershed in Bocheong river basin as a target basin was classified as 4th rivers by Strahler's ordering scheme. The optimization technique was applied to the SCE-UA, the estimated optimal parameters are as follows. $u_c$ : 0.589 m/s, $u_h$ : 0.021 m/s, $D_c$ : $34.469m^2/s$, $D_h$ : $0.1333m^2/s$. As a verification for the estimated parameters, the error of average peak flow was about 11 % and the error of peaktime was 0.3 hr. By examining the variability of parameters, the channel diffusion coefficient didn't have significant effect on hydrological response function. by considering these results, the model is expected to be simplified in the future.

An Indirect Approach Determining Parameters of Clark's Model Based on Model Fitting to the Gamma Distribution function (Gamma분포형 함수 적합을 이용한 Clark 모형의 매개변수 간접추정)

  • Seong, Kee-Won
    • Journal of Korea Water Resources Association
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    • v.36 no.2
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    • pp.223-235
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    • 2003
  • An indirect or supplementary approach is proposed for determining the parameters of the Clark's model in order to improve existing defect in estimating the parameters. The gamma-distribution type function is employed to represent the Clark's model, which takes the same form as the Nash's model, so that parameter estimation is not difficult since it can be performed with a simple optimization process. Analytic forms of Clark's models parameters are introduced using parameters of the proposed methodology to give traditional form of Clark's. An application to a watershed has shown that the proposed approach can preserve the properties of observed data. Based the application, the new approach is recommended as an alternative to the existing parameter estimating methodology.

Gateway Discovery Algorithm Based on Multiple QoS Path Parameters Between Mobile Node and Gateway Node

  • Bouk, Safdar Hussain;Sasase, Iwao;Ahmed, Syed Hassan;Javaid, Nadeem
    • Journal of Communications and Networks
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    • v.14 no.4
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    • pp.434-442
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    • 2012
  • Several gateway selection schemes have been proposed that select gateway nodes based on a single Quality of Service (QoS) path parameter, for instance path availability period, link capacity or end-to-end delay, etc. or on multiple non-QoS parameters, for instance the combination of gateway node speed, residual energy, and number of hops, for Mobile Ad hoc NETworks (MANETs). Each scheme just focuses on the ment of improve only a single network performance, i.e., network throughput, packet delivery ratio, end-to-end delay, or packet drop ratio. However, none of these schemes improves the overall network performance because they focus on a single QoS path parameter or on set of non-QoS parameters. To improve the overall network performance, it is necessary to select a gateway with stable path, a path with themaximum residual load capacity and the minimum latency. In this paper, we propose a gateway selection scheme that considers multiple QoS path parameters such as path availability period, available capacity and latency, to select a potential gateway node. We improve the path availability computation accuracy, we introduce a feedback system to updated path dynamics to the traffic source node and we propose an efficient method to propagate QoS parameters in our scheme. Computer simulations show that our gateway selection scheme improves throughput and packet delivery ratio with less per node energy consumption. It also improves the end-to-end delay compared to single QoS path parameter gateway selection schemes. In addition, we simulate the proposed scheme by considering weighting factors to gateway selection parameters and results show that the weighting factors improve the throughput and end-to-end delay compared to the conventional schemes.

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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Model of Least Square Support Vector Machine (LSSVM) for Prediction of Fracture Parameters of Concrete

  • Kulkrni, Kallyan S.;Kim, Doo-Kie;Sekar, S.K.;Samui, Pijush
    • International Journal of Concrete Structures and Materials
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    • v.5 no.1
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    • pp.29-33
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    • 2011
  • This article employs Least Square Support Vector Machine (LSSVM) for determination of fracture parameters of concrete: critical stress intensity factor ($K_{Ic}^s$) and the critical crack tip opening displacement ($CTOD_c$). LSSVM that is firmly based on the theory of statistical learning theory uses regression technique. The results are compared with a widely used Artificial Neural Network (ANN) Models of LSSVM have been developed for prediction of $K_{Ic}^s$ and $CTOD_c$, and then a sensitivity analysis has been performed to investigate the importance of the input parameters. Equations have been also developed for determination of $K_{Ic}^s$ and $CTOD_c$. The developed LSSVM also gives error bar. The results show that the developed model of LSSVM is very predictable in order to determine fracture parameters of concrete.

Extraction of Passive Device Model Parameters Using Genetic Algorithms

  • Yun, Il-Gu;Carastro, Lawrence A.;Poddar, Ravi;Brooke, Martin A.;May, Gary S.;Hyun, Kyung-Sook;Pyun, Kwang-Eui
    • ETRI Journal
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    • v.22 no.1
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    • pp.38-46
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    • 2000
  • The extraction of model parameters for embedded passive components is crucial for designing and characterizing the performance of multichip module (MCM) substrates. In this paper, a method for optimizing the extraction of these parameters using genetic algorithms is presented. The results of this method are compared with optimization using the Levenberg-Marquardt (LM) algorithm used in the HSPICE circuit modeling tool. A set of integrated resistor structures are fabricated, and their scattering parameters are measured for a range of frequencies from 45 MHz to 5 GHz. Optimal equivalent circuit models for these structures are derived from the s-parameter measurements using each algorithm. Predicted s-parameters for the optimized equivalent circuit are then obtained from HSPICE. The difference between the measured and predicted s-parameters in the frequency range of interest is used as a measure of the accuracy of the two optimization algorithms. It is determined that the LM method is extremely dependent upon the initial starting point of the parameter search and is thus prone to become trapped in local minima. This drawback is alleviated and the accuracy of the parameter values obtained is improved using genetic algorithms.

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