• 제목/요약/키워드: derivative models

검색결과 132건 처리시간 0.023초

새로운 캅사이신 유도체 DA-5018의 국소자극성에 관한 연글 (Studies on the Local Irritation of DA-5018, a New Capsaicin Derivative)

  • 손문호;배은주;신명수;김희기;김순희;김원배;양중익
    • Biomolecules & Therapeutics
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    • 제5권2호
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    • pp.150-157
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    • 1997
  • Capsaicin cream has been used to attenuate the pain associated with diabetic neuropathy, rheum-atoid arthritis, osteoarthritis and postherpetic neuralgia. But its common side effect, local irritation, limits the use of it and there is still a need for a new analgesic devoid of this side effect. This study was conducted to compare the local irritant effect of DA-5018, a new capsaicin derivative, with that of capsaicin in various animal models and human beings. Capsaicin, applied topically to the mouse ear, produced dose-dependent increase of ear volume and the frequency of ear scratching behavior in mice. Neither ear volume nor scratching behavior was affected by DA-5018. In eye wiping test of rat, DA-5018 was 10 times less irritant than capsaicin. Capsaicin administered intradermally into the rat paw elicited paw lick/lift response with a potency which was three times that of DA-5018. Zostrix-HP (0.075% capsaicin cream), but not DA-50180.3% cream, increased ear volume of rat and induced thermal hyperalgesia in normal and carrageenan inflamed paws. Six day-treatment of Zostrix-HP failed to develop tolerance against this thermal hyperalgesia. In human beings, Zostrix-HP produced burning sensation and itching in more than 90% of volunteers involved and its maximum irritant effect was significantly higher than that of DA-5018 cream. These results suggest that local irritation and burning sensation produced by DA-5018 is much less than capsaicin.

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Determination of flutter derivatives by stochastic subspace identification technique

  • Qin, Xian-Rong;Gu, Ming
    • Wind and Structures
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    • 제7권3호
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    • pp.173-186
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    • 2004
  • Flutter derivatives provide the basis of predicting the critical wind speed in flutter and buffeting analysis of long-span cable-supported bridges. In this paper, one popular stochastic system identification technique, covariance-driven Stochastic Subspace Identification(SSI in short), is firstly presented for estimation of the flutter derivatives of bridge decks from their random responses in turbulent flow. Secondly, wind tunnel tests of a streamlined thin plate model and a ${\Pi}$ type blunt bridge section model are conducted in turbulent flow and the flutter derivatives are determined by SSI. The flutter derivatives of the thin plate model identified by SSI are very comparable to those identified by the unifying least-square method and Theodorson's theoretical values. As to the ${\Pi}$ type section model, the effect of turbulence on aerodynamic damping seems to be somewhat notable, therefore perhaps the wind tunnel tests for flutter derivative estimation of those models with similar blunt sections should be conducted in turbulent flow.

점탄성 감쇠기의 비선형거동을 고려한 선형모델 해석 (Linear Modeling of Viscoelastic Dampers Considering Nonlinear Dynamic Behavior)

  • 김진구;권영집;민경원
    • 한국구조물진단유지관리공학회 논문집
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    • 제6권1호
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    • pp.171-177
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    • 2002
  • The viscoelastic dampers are considered to be one of the most efficient means of upgrading existing structures against seismic loads. Generally in the dynamic analysis of a structure with added viscoelastic dampers the internal forces of the dampers are represented by constants that are linearly proportional to displacement and velocity. The purpose of this study is to verify the validity of the linear Kelvin model by comparing the results from the linear analysis with those obtained from the more rigorous nonlinear model such as fractional derivative model. According to the results the structural responses of 1-DOF structure obtained using the linear model are very close to those obtained from nonlinear model. However for multi-D0F structure the difference between the results from both models is enlarged as a results of the assumptions associated with the linear modeling of the viscoelastic dampers.

Fault Detection in the Semiconductor Etch Process Using the Seasonal Autoregressive Integrated Moving Average Modeling

  • Arshad, Muhammad Zeeshan;Nawaz, Javeria Muhammad;Hong, Sang Jeen
    • Journal of Information Processing Systems
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    • 제10권3호
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    • pp.429-442
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    • 2014
  • In this paper, we investigated the use of seasonal autoregressive integrated moving average (SARIMA) time series models for fault detection in semiconductor etch equipment data. The derivative dynamic time warping algorithm was employed for the synchronization of data. The models were generated using a set of data from healthy runs, and the established models were compared with the experimental runs to find the faulty runs. It has been shown that the SARIMA modeling for this data can detect faults in the etch tool data from the semiconductor industry with an accuracy of 80% and 90% using the parameter-wise error computation and the step-wise error computation, respectively. We found that SARIMA is useful to detect incipient faults in semiconductor fabrication.

단일 유연 링크 매니퓰레이터의 복합 퍼지 제어 (Composite Fuzzy Control of a Single Flexible Link Manipulator)

  • 김재승;이수한
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.353-353
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    • 2000
  • To control a light weight flexible manipulator, a composite fuzzy controller is proposed. The controller is designed based on two time scaled models. A singular perturbation technique is applied for deriving the models. The proposed controller, however, does not use the complex equilibrium manifold equations, which are usually needed in the controller based on the two time scaled models. The controller for a slow sub-model and a fast sub-model are T-S type fuzzy controllers, which use 3 linguistic variables for each sub-model. A step trajectory is used in simulations as a reference trajectory of joint motions. The results of simulations with the proposed controller show excellent damping of flexible motions compared to a controller with derivative control of flexible motions.

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Thermoelastic deformation properties of non-localized and axially moving viscoelastic Zener nanobeams

  • Ahmed E. Abouelregal;Badahi Ould Mohamed;Hamid M. Sedighi
    • Advances in nano research
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    • 제16권2호
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    • pp.141-154
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    • 2024
  • This study aims to develop explicit models to investigate thermo-mechanical interactions in moving nanobeams. These models aim to capture the small-scale effects that arise in continuous mechanical systems. Assumptions are made based on the Euler-Bernoulli beam concept and the fractional Zener beam-matter model. The viscoelastic material law can be formulated using the fractional Caputo derivative. The non-local Eringen model and the two-phase delayed heat transfer theory are also taken into account. By comparing the numerical results to those obtained using conventional heat transfer models, it becomes evident that non-localization, fractional derivatives and dual-phase delays influence the magnitude of thermally induced physical fields. The results validate the significant role of the damping coefficient in the system's stability, which is further dependent on the values of relaxation stiffness and fractional order.

레이저 다이오드의 전기적 미분특성에 관한 연구 (Electrical Derivative Characteristics of Lsaer Diodes)

  • 김창균;도만희;김상배
    • 전자공학회논문지A
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    • 제30A권7호
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    • pp.38-46
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    • 1993
  • Based on the close correlation between the optoelectronic and electrical characteristics of laser diodes, this paper is to present an exact model for electrical characteristics of laser diodes with bulk active layers so that the optoelectronic characteristics may be estimated from the electrical Characteristics. Among the considered models, the most exact model is shown to be one which uses the Fermi-Dirac integral and the bimolecular recombination and takes into account the energy-gap shrinkage with the injected carrier density.

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Modelling KOSPI200 Data Based on GARCH(1,1) Parameter Change Test

  • Park, Si-Yun;Lee, Sang-Yeol
    • Journal of the Korean Data and Information Science Society
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    • 제18권1호
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    • pp.11-16
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    • 2007
  • Since the seminal work of Engle (1982), many researchers and practitioners have developed ARCH-type models to deal with volatility modelling, which, for instance, is crucial to perform the task of derivative pricing, measuring risk, and risk hedging. In this paper, we base the GARCH(1,1) model to analyze the KOSPI200 data, and perform the CUSUM test for detecting parameter changes in the GARCH model. It is shown that the data suffers from a parameter change.

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강제 가진에 의한 교량 플러터계수 추출 (Extraction of bridge flutter derivatives by a forced excitation)

  • 이승호;권순덕
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2009년도 춘계학술대회 논문집
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    • pp.538-544
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    • 2009
  • A vibration excitation system was designed and built of forced vibration experiments for using stepping motor and load cell. The identified flutter derivatives of the thin-plate acrylic model were very close to the analytical results of the idealized plate presented by Theodorsen. Five types of sectional models were tested in the wind tunnel using the proposed forced vibration method. To investigate the frequency, amplitude and angle of attack effects on flutter derivatives.

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분광분석법을 이용한 단립 쌀의 함수율 및 단백질 함량 예측모델 개발 (Development of Prediction Model for Moisture and Protein Content of Single Kernel Rice using Spectroscopy)

  • 김재민;최창현;민봉기;김종훈
    • Journal of Biosystems Engineering
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    • 제23권1호
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    • pp.49-56
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    • 1998
  • The objectives of this study were to develop models to predict the contents of moisture and protein of single kernel of brown rice based on visible/NIR (near-infrared) spectroscopic technique. The reflectance spectra of rice were obtained in the range of the wavelength 400 to 2,500 nm with 2 nm intervals. Multiple linear regression(MLR) and partial least squares (PLS) were used to develop the models. The MLR model using the first derivative spectra(10 nm of gap) with Standard Normal Variate and Detrending (SNV and Drt.) preprocessing showed the best results to predict moisture content of the sin린e kernel brown rice. To predict the protein content of a single kernel of brown ricer the PLS model used the raw spectra with multiplicative scatter correction(MSC) preprocessing over the wavelength of 1,100~1,500 nm.

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