• Title/Summary/Keyword: derivative models

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Design of Multivariable PID Controllers: A Comparative Study

  • Memon, Shabeena;Kalhoro, Arbab Nighat
    • International Journal of Computer Science & Network Security
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    • v.21 no.8
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    • pp.212-218
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    • 2021
  • The Proportional Integral Derivative (PID) controller is the most popular industrial controller and more than 90% process industries use this controller. During the past 50 years, numerous good tuning methods have been proposed for Single Input Single Output Systems. However, design of PI/PID controllers for multivariable processes is a challenge for the researchers. A comparative study of three PID controllers design methods has been carried-out. These methods include the DS (Direct Synthesis) method, IMC (Internal model Control) method and ETF (Effective Transfer Function) method. MIMO PID controllers are designed for a number of 2×2, 3×3 and 4×4 process models with multiple delays. The performance of the three methods has been evaluated through simulation studies in Matlab/Simulink environment. After extensive simulation studies, it is found that the Effective Transfer Function (ETF) Method produces better output responses among two methods. In this work, only decentralized methods of PID controllers have been studied and investigated.

3D stress-fractional plasticity model for granular soil

  • Song, Shunxiang;Gao, Yufeng;Sun, Yifei
    • Geomechanics and Engineering
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    • v.17 no.4
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    • pp.385-392
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    • 2019
  • The present fractional-order plasticity models for granular soil are mainly established under the triaxial compression condition, due to its difficult in analytically solving the fractional differentiation of the third stress invariant, e.g., Lode's angle. To solve this problem, a three dimensional fractional-order elastoplastic model based on the transformed stress method, which does not rely on the analytical solution of the Lode's angle, is proposed. A nonassociated plastic flow rule is derived by conducting the fractional derivative of the yielding function with respect to the stress tensor in the transformed stress space. All the model parameters can be easily determined by using laboratory test. The performance of this 3D model is then verified by simulating multi series of true triaxial test results of rockfill.

Knowledge-based learning for modeling concrete compressive strength using genetic programming

  • Tsai, Hsing-Chih;Liao, Min-Chih
    • Computers and Concrete
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    • v.23 no.4
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    • pp.255-265
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    • 2019
  • The potential of using genetic programming to predict engineering data has caught the attention of researchers in recent years. The present paper utilized weighted genetic programming (WGP), a derivative model of genetic programming (GP), to model the compressive strength of concrete. The calculation results of Abrams' laws, which are used as the design codes for calculating the compressive strength of concrete, were treated as the inputs for the genetic programming model. Therefore, knowledge of the Abrams' laws, which is not a factor of influence on common data-based learning approaches, was considered to be a potential factor affecting genetic programming models. Significant outcomes of this work include: 1) the employed design codes positively affected the prediction accuracy of modeling the compressive strength of concrete; 2) a new equation was suggested to replace the design code for predicting concrete strength; and 3) common data-based learning approaches were evolved into knowledge-based learning approaches using historical data and design codes.

Design of Multivariable PID Controllers: A Comparative Study

  • Memon, Shabeena;Kalhoro, Arbab Nighat
    • International Journal of Computer Science & Network Security
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    • v.21 no.9
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    • pp.11-18
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    • 2021
  • The Proportional Integral Derivative (PID) controller is the most popular industrial controller and more than 90% process industries use this controller. During the past 50 years, numerous good tuning methods have been proposed for Single Input Single Output Systems. However, design of PI/PID controllers for multivariable processes is a challenge for the researchers. A comparative study of three PID controllers design methods has been carried-out. These methods include the DS (Direct Synthesis) method, IMC (Internal model Control) method and ETF (Effective Transfer Function) method. MIMO PID controllers are designed for a number of 2×2, 3×3 and 4×4 process models with multiple delays. The performance of the three methods has been evaluated through simulation studies in Matlab/Simulink environment. After extensive simulation studies, it is found that the Effective Transfer Function (ETF) Method produces better output responses among two methods. In this work, only decentralized methods of PID controllers have been studied and investigated.

X-RAY PROPERTIES OF THE PULSAR PSR J0205+6449 IN 3C 58

  • Kim, Minjun;An, Hongjun
    • The Bulletin of The Korean Astronomical Society
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    • v.45 no.1
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    • pp.53.2-53.2
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    • 2020
  • We measure X-ray timing and spectral properties of the pulsar PSR J0205+6449. Pulsar's rotation frequency ν = 15.20102357(9) s-1 and its derivative ${\dot{\nu}}=-4.5(1){\times}10^{-11}s^{-2}$ are measured, and the pulsed spectrum of 2-30 keV is model of power law with photon index ��psr = 1.07(16) and F2-30 keV = 7.3(6) × 10-13 erg cm-2 s-1. We use thermal emission models and non-thermal model to fit the pulsar spectrum and measure the surface temperature and luminosity of the pulsar. The surface temperature T∞ = 0.5-0.8 MK and luminosity Lth = 1-5 × 1032 erg s-1 are measure, and this result verifies the previous results known to have low surface temperature and luminosity for the age range of

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3-(Naphthalen-2-yl(propoxy)methyl)azetidine hydrochloride attenuates MPP+-induced cytotoxicity by regulating oxidative stress and mitochondrial dysfunction in SH-SY5Y cells

  • Yang, Seung-Ju;Yang, Ji Woong;Na, Jung-Min;Ha, Ji Sun;Choi, Soo Young;Cho, Sung-Woo
    • BMB Reports
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    • v.51 no.11
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    • pp.590-595
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    • 2018
  • Parkinson's disease (PD) is a common chronic neurodegenerative disease mainly caused by the death of dopaminergic neurons. However, no complete pharmacotherapeutic approaches are currently available for PD therapies. 1-methyl-4-phenylpyridinium $(MPP^+)$-induced SH-SY5Y neurotoxicity has been broadly utilized to create cellular models and study the mechanisms and critical aspects of PD. In the present study, we examined the role of a novel azetidine derivative, 3-(naphthalen-2-yl(propoxy)methyl)azetidine hydrochloride (KHG26792), against $MPP^+$-induced neurotoxicity in SH-SY5Y cells. Treatment of KHG26792 significantly attenuated $MPP^+$-induced changes in the protein levels of Bcl-2 and Bax together with efficient suppression of $MPP^+$-induced activation of caspase-3 activity. KHG26792 also attenuated mitochondrial potential and levels of ROS, $Ca^{2+}$, and ATP in $MPP^+$-treated SH-SY5Y cells. Additionally, KHG26792 inhibited the induced production of nitric oxide and malondialdehyde. Moreover, the protective effect of KHG26792 is mediated through regulation of glutathione peroxidase and GDNF levels. Our results suggest a possibility that KHG26792 treatment significantly protects against $MPP^+$-induced neurotoxicity in SH-SY5Y cells and KHG26792 may be a valuable therapeutic agent for the treatment of PD induced by an environmental toxin.

Analgesic Action Mechanism of DA-5018, a New Capsaicin Derivative : Relationship to Opiate :Receptors and Prostanoids (새로운 캅사이신 유도체 DA-5018의 진통활성 기전연구: Opiate 수용체 및 :Prostanoid와의 상관성)

  • 손미원;손문호;배은주;김순희;김원배;양중의
    • Biomolecules & Therapeutics
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    • v.5 no.1
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    • pp.87-93
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    • 1997
  • DA-5018, a new capsaicin derivative, showed potent analgesic effect comparable to that of morphine in various experimental acute pain models. in this study, whether the analgesic mechanism of DA-5018 is related to opiate receptors or prostanoids was investigated. The affinity of DA-5018 for opiate receptor was determined by receptor binding assay. The Ki values of DA-5018 for nonspecific and specific $\mu$, $textsc{k}$, $\delta$-opiate receptor was 299$\pm$8.88, 735$\pm$215, 2930$\pm$ 163, 1550$\pm$813 nM, respectively and DA-5018 exhibited lower affinity than morphine. DA-5018 (10-"~3$\times$10-′M) inhibited electrically-evoked contractions of the guinea ply ileum and rat vas deferens, and these inhibition was not antagonized by naloxone(10 nM), an opiate receptor antagonist. Antagonism of analgesic effect of 7A-5018 by naloxone was examined by tail pinch test. Analgesic action of DA-5018(0.1 ~2 mg/kg, 5.c.) was not antagonized by naloxone(1 mg/rg, i.p.). These results indicate that pharmacological action of DA-5018 is not related with opiate receptor. Cyclooxygenase and 5-lipoxygenase activities in rat peritoneal neutrophil treated with A23187 and arachidonic acid were measured by radioimmunoassay. DA-5018 stimulated the cyclooxygenase activity and the concentration show-ing the two fold increase of activity was 124$\mu$M. DA-5018 slightly inhibited 5-lipoxygenase activity and these results together indicate that analgesic action of 3A-5018 is not mediated through inhibition of cyclooxy genase or lipoxygenase. These results suggest that the analgesic effect of DA-5018 is not due to blocking opiate receptor or to inhibiting the synthesis of prostanoids in the arachidonic acid metabolism pathway.

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Density Functional Theory (DFT) Study of Gas-phase O.C Bond Dissociation Energy of Models for o-TEMPO-Bz-C(O)-Peptide: A Model Study for Free Radical Initiated Peptide Sequencing

  • Kwon, Gyemin;Kwon, Hyuksu;Lee, Jihye;Han, Sang Yun;Moon, Bongjin;Oh, Han Bin;Sung, Bong June
    • Bulletin of the Korean Chemical Society
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    • v.35 no.3
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    • pp.770-774
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    • 2014
  • The bond dissociation energy (BDE) of the chemical bond between the carbon and oxygen atoms of a simple TEMPO-derivative is calculated by employing the density functional theory, the $2^{nd}$ order M${\phi}$ller-Plesset (MP2) perturbation theory, and complete basis set (CBS) methods. We find that BDE of the positive ion of the TEMPO-derivative is larger at least by 7 kcal/mol than that of the negative ion, which implies that the dissociation reaction rate of the positive ion should be slower than that of the negative ion. Such theoretical predictions are contrary to the results of our previous experiments (Anal. Chem. 2013, 85, 7044), in which the larger energy was required for negative o-TEMPO-Bz-C(O)-peptides to undergo the dissociation reactions than for the positive ones. By comparing our theoretical results to those of the experiments, we conclude that the dissociation reaction of o-TEMPO-Bz-C(O)-peptide should occur in a complicated fashion with a charge, either positive or negative, probably being located on the amino acid residues of the peptide.

The Singular Position Detection Method from the Measured Path Loss Data for the Cellular Network (이동 통신 망에서 측정하여 계산된 경로 손실의 급격한 변동 위치 추출 방법)

  • Park, Kyung-Tae;Bae, Sung-Hyuk
    • Journal of the Institute of Convergence Signal Processing
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    • v.15 no.1
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    • pp.9-14
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    • 2014
  • The path loss data was re-calculated according to the distance between the base station and a mobile station in the mobile telecommunications network. In this paper, the averaged path loss data was plotted with the conventional path loss models(free space, plane earth, Hata model ${\ldots}$). The standard deviations for the 2 Km, 1 Km, 0.5 Km-interval averaged path loss were 2.29 dB, 3.39 dB, 4.75 dB, respectively. Additionally, the derivative values for the 2 Km, 1 Km, 0.5 Km-interval averaged path loss were evaluated to find the positions with more than 1 times or 2times of the standard deviation. The situations with the sharply fluctuated path loss were calculated to 5 positions in the 2 Km interval, to 7 positions in the 1 Km interval, to 19 positions in the 0.5 Km interval, respectively. And, the exact distances between the base station and a mobile station were found with the sharply fluctuated path loss.

Analysis of Nonlinear Behavior in Love Model as External Force with Gaussian Fuzzy Membership Function (가우시안 퍼지 소속 함수를 외력으로 가진 사랑 모델에서의 비선형 거동 해석)

  • Bae, Young-Chul
    • Journal of the Korean Institute of Intelligent Systems
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    • v.27 no.1
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    • pp.29-34
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    • 2017
  • Recently, studying chaotic dynamic have been concerned by many researchers in areas of physics, chemistry, mathematics, engineering and social science. Especially, model of addiction, happiness, family and love become major research subjects in the social science. Among these models, love is one of the four emotions that human being have. There are many definitions for love, however, each definitions of love does not coincide with each other. Recently, one of the most important efforts for research is love and it is represented by derivative equation. Then they try to find nonlinear or chaotic behavior from this derivative equation. This paper propose Gaussian fuzzy membership function in order to make external force that are close to action and awareness of human based on love model of Romeo and Juliet with external force. This paper also confirms the existence of nonlinear characteristics through time series and phase portrait.