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[IEEE 2018 International Seminar on Application for Technology of Information and Communication (iSemantic) - Semarang, Indonesia (2018.9.21-2018.9.22)] 2018 International Seminar on Application for Technology of Information and Communication - Comparison of First Order Differential Algorithm, Perturb and Observe (P&O) and Newton Raphson Methods for PV Application in DC Microgrid Isolated System
摘要： The necessary for energy always increases every year, so it is necessary energy alternative to overcome the phenomenon. From some alternative energy that is currently widely developed is solar energy. Unfortunately the use of solar energy with the help of solar panels produces power that varies according to the irradiation received and the temperature on the solar panel. Irradiation is the emission of energy coming from the sun. This parameter causes the output power characteristic curve to be non-linear. And the power generated by PV has not reached the maximum power point. To overcome this problem requires an arrangement to find the maximum power point and make it stable at that point. Therefore, this paper proposes "Comparison of First Order Differential Algorithms, Perturb and Observe(P&O) and Newton Raphson Methods for PV Application in DC Microgrid Isolated System" so that the maximum power point can be achieved quickly and accurately. In this paper we tried to compare 3 methods of First-order Differential, P & O (Perturb and Observe) and Newton Raphson by using ZETA Converter as its object in switching settings. By using the simulation can be obtained the results of tracking speed and maximum power level. The results of the simulation show that error power the First-order Differential is 4%, P & O is 0.26389% and Newton Raphson is 0.45178%. It is evident that Raphson's newton algorithm is superior to speed and accuracy.
关键词： Solar Panel,First-Order Differential,Maximum Power Point Tracking (MPPT),Newton Raphson Method,Perturb and Observe (P&O)
更新于2025-09-04 15:30:14
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Quasi-Static Surface-PEEC Modeling of Electromagnetic Problem With Finite Dielectrics
摘要： This paper presents a quasi-static surface-based partial element equivalent circuit (PEEC) model for electromagnetic problems consisting of coupled conductors and heterogeneous dielectrics of finite size. The PEEC model is based on the surface equivalent principle. Unlike the traditional surface-based PEEC models, in which the integral equations are set up by enforcing the field continuity in the true field region, the homogeneous integral equations in this model are obtained by enforcing the tangential null field condition in the null field regions. Simplified integral equations are obtained under the quasi-static assumption, in which the circuit elements carrying electric currents and magnetic charges on the dielectric surfaces are vanished. Consequently, the size of the subcircuit describing dielectrics is reduced significantly compared to the full-wave surface-PEEC (S-PEEC) model. Since the quasi-static S-PEEC model only contains frequency-independent circuit elements, it can be conveniently used for time-domain simulation. Three numerical examples are presented to validate the new PEEC model for typical embedded RF passive components, packaging and interconnection problems in both the frequency domain and the time domain. Excellent agreement is observed between the results of the proposed PEEC model, S-PEEC model, and those of commercial software within the quasi-static frequency range.
关键词： Dielectrics,integral equations,interconnection,partial element equivalent circuit (PEEC) method,embedded passives
更新于2025-09-04 15:30:14
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Estimating the Influence of Quantum Noises on the Quality of Material Identification by the Dual-Energy Method
摘要： A mathematical model has been developed to describe the radiation transparency of a test object with allowance for quantum noise. The technique of estimating the effective atomic number of the test object by the dual-energy method has been improved based on the analysis of radiation transparency with regard to necessary restrictions and recommendations. An algorithm is presented for the statistical evaluation of the influence of quantum noises on the quality of test-object material identification by the dual-energy method. An example is given of using the algorithm in a baggage and carry-on inspection system that has the maximum X-ray energies of 80 and 160 keV and is equipped with total-absorption detectors.
关键词： quantum noise,dual-energy method,effective atomic number,material identification,digital radiography
更新于2025-09-04 15:30:14
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Structural, optical, and dielectric studies of LaFe1?xMoxO3 (x?=?0.0, 0.5) perovskite materials
摘要： The structural, optical, and dielectric properties of LaFe1?xMoxO3 (x = 0.0, 0.5) synthesized by the sol–gel method were investigated by X-ray diffraction (XRD), Raman scattering, and impedance spectroscopy. XRD analysis revealed that the x = 0.5 compound is single-phase and orthorhombic, with space group Pbnm, similar to the parent x = 0.0 compound but with larger lattice parameters and/or a larger unit-cell volume. The Raman scattering spectra revealed local lattice distortions in the x = 0.5 compound and spin–phonon coupling related to the magnetic transition (Néel) temperature. The impedance data were well fitted with an R(R1-CPE1)//(R2-CPE2) equivalent electrical circuit, demonstrating the contributions of both grains and grain boundaries. The temperature (300–500 K) and frequency (100 Hz–1 MHz) dependences of the dielectric properties showed that Mo substitution adversely affected the dielectric parameters.
关键词： X-ray diffraction,LaFe1?xMoxO3,impedance spectroscopy,Raman scattering,sol–gel method,dielectric properties
更新于2025-09-04 15:30:14
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[American Society of Agricultural and Biological Engineers 2017 Spokane, Washington July 16 - July 19, 2017 - ()] 2017 Spokane, Washington July 16 - July 19, 2017 - <i>Variety classification of maize kernels using near infrared (NIR) hyperspectral imaging</i>
摘要： Variety classification of maize kernels was evaluated using near infrared (NIR) hyperspectral imaging in this work. Firstly, NIR hyperspectral images of kernels of four widely used maize varieties were acquired within effective spectral range of 1000-2500 nm. Spectral math was used to compensate for minor lighting differences, and band math combined with threshold method was used to remove the background from images. Minimum noise fraction (MNF) was adopted to reduce noise. Texture features (mean, variance, homogeneity, contrast, dissimilarity, entropy, second moment, and correlation) as appearance character of each maize kernel were calculated and extracted to establish classification model combined with spectra data. Moving average smoothing and standard normal variate were applied on the raw spectra extracted from hyperspectral images. Four optimal wavelengths (1352.20 nm, 1615.50 nm, 1733.10 nm, and 2478.20 nm) were selected by competitive adaptive reweighted sampling (CARS) method. Partial least squares discriminant analysis (PLSDA) was employed to build varieties classification models, based on full wavelength data, the four wavelengths data, and combination of spectral and textural features at four wavelengths, respectively. Results demonstrated that PLSDA model based on combination of spectral and textural features had the best performance with accuracies of 0.89, 0.83 for calibration and prediction set, which indicated the hyperspectral imaging technique with combination of spectral and textural features had a potential of application for variety classification.
关键词： Variety classification,Maize kernel,NIR hyperspectral imaging,Partial least squares discriminant analysis (PLSDA),Competitive adaptive reweighted sampling (CARS) method
更新于2025-09-04 15:30:14
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VALIDATION STUDY OF STEROIDAL DRUGS (DEXAMETHASONE AND BETAMETHASONE) BY U.V. SPECTROPHOTOMETRIC METHOD
摘要： Objective: The present investigation involves development and validation of ultraviolet (UV) spectroscopic method for estimation of dexamethasone and betamethasone in a pharmaceutical dosage as per International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines. Method: Betamethasone and dexamethasone were dissolved in 50 mL Methanol: water (1:2) and 50 mL distilled water, respectively. The method was validated for accuracy, precision, linearity, ruggedness, and robustness to check its consistency. Result: The λmax or the absorption maxima of both the drugs was found to be 241 nm. A linear response was observed in the range of 10–20 μg/mL. Conclusion: The method could be applied for the analysis of marketed tablets and also can be used for the routine analysis of dexamethasone and betamethasone in bulk formulations using UV method. It is suitable for the intended purpose especially in forensic science laboratories and other laboratories involved in the pharmaceutical analysis.
关键词： Accuracy,Method validation,Betamethasone,Precision,Dexamethasone,Ultraviolet spectroscopy
更新于2025-09-04 15:30:14
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A spectral domain approach for the calculation of the scattering of the stratified uniaxial electric anisotropic media under point source excitation with arbitrary orientation
摘要： A method for the calculation of the scattering of the strati?ed uniaxial electric anisotropic media (UEAM) under point source excitation with arbitrary orientation is presented. In this method, the total ?eld is decomposed into three parts, the radiated ?eld of the point source in free space, the re?ected ?eld from the top interface of the UEAM and the transmitted ?eld after multiple re?ections in the anisotropic layer. The three parts are derived in spectral domain respectively and can be expressed by using Fourier transform. Then the saddle point technique (SPT) is introduced to obtain an asymptotic solution of the scattered ?eld. Results from the asymptotic solution are compared with the results calculated by the method of moments (MOM) and the comparison shows good agreement.
关键词： uniaxial electric anisotropic,scattering,spectral domain method,Point source,saddle point technique
更新于2025-09-04 15:30:14
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New Analytical Formulae to Calibrate Well-type Scintillation Detectors Efficiency
摘要： Direct Mathematical calculations for the absolute efficiency of well-type gamma ray scintillation crystals are described. Calculated detection efficiencies are drawn for two commonly used well crystals. Comparisons are made between present works and published Monte Carlo values. The present approach proved quite success in predicting the efficiency of well type detectors providing only the geometry and materials of the system formed of source, detector and shielding as well as the energy of the emitted photons.
关键词： Absolute efficiency,Well-type detector,Gamma-spectroscopy,New mathematical method
更新于2025-09-04 15:30:14