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71.
B. Marion S. Rummel A. Anderberg 《Progress in Photovoltaics: Research and Applications》2004,12(8):593-607
By means of bilinear interpolation and four reference current–voltage (I–V) curves, an I–V curve of a photovoltaic (PV) module is translated to desired conditions of irradiance and PV module temperature. The four reference I–V curves are measured at two irradiance and two PV module temperature levels and contain all the essential PV module characteristic information for performing the bilinear interpolation. The interpolation is performed first with respect to open‐circuit voltage to account for PV module temperature, and second with respect to short‐circuit current to account for irradiance. The translation results over a wide range of irradiances and PV module temperatures agree closely with measured values for a group of PV modules representing seven different technologies. Root‐mean‐square errors were 1·5% or less for the I–V curve parameters of maximum power, voltage at maximum power, current at maximum power, short‐circuit current, and open‐circuit voltage. The translation is applicable for determining the performance of a PV module for a specified test condition, or for PV system performance modeling. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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Dimitrios Tzovaras Nikos Grammalidis Michael G. Strintzis 《Signal Processing: Image Communication》1998,11(3):205-230
In the present paper techniques are examined for the coding of the depth map and disparity fields for stereo or multiview image communication applications. It is assumed that both the left and right channels of the multiview image sequence are coded using block- or object-based methods. A dynamic programming algorithm is used to estimate a disparity field between each stereo image pair. Depth is then estimated and occlusions are optionally detected, based on the estimated disparity fields. Spatial interpolation techniques are examined based on the disparity/depth information and the detection of occluded regions using either stereoscopic or trinocular camera configurations. It is seen that the presence of a third camera at the transmitter site improves the estimation of disparities, the detection of occlusions and the accuracy of the resulting spatial interpolation at the receiver. Various disparity field and depth map coding techniques are then proposed and evaluated, with emphasis given to the quality of the resulting intermediate images at the receiver site. Block-based and wireframe modeling techniques are examined for the coding of isolated depth or disparity map information. Further, 2D and 3D motion compensation techniques are evaluated for the coding of sequences of depth or disparity maps. The motion fields needed may be available as a byproduct of block-based or object-based coding of the intensity images. Experimental results are given for the evaluation of the performance of the proposed coding and spatial interpolation methods. 相似文献
76.
Elvi Räisänen-Ruotsalainen Timo Rahkonen Juha Kostamovaara 《Analog Integrated Circuits and Signal Processing》1998,15(1):49-57
The main features of two time-to-digital convertersbased on interpolation are presented, together with some measurementresults. The first converter is based on digital delay line interpolatorsand has been implemented in a 1.2 µm CMOS process.It has a single-shot resolution of 1 ns (-value)and a nonlinearity less than ±50 ps in the measurementrange 5 to 500 ns. The power consumption of the circuit is 15mW. The second time digitizer has analog interpolators basedon time-to-voltage conversion and has been implemented in a 1.2 µm BiCMOS process. It has a single-shot resolutionof 50 ps and a nonlinearity less than 150 ps in the measurementrange 1 to 300 ns. The power consumption of this circuit is 200mW. 相似文献
77.
An 8-bit, 200 MSPS Folding and Interpolating ADC 总被引:1,自引:0,他引:1
An 8-bit, 200 MSPS folding and interpolating analog-to-digitalconverter, ADC, has been implemented in a 1.2 µmBiCMOS-process. It achieves 7.5 effective bits with a power dissipationof 575mW. The active area is 4mm2. The implementationand measured results are presented. A simple analytical modelfor the interpolation-induced nonlinearity in a folding and interpolatingADC using sinusoidal folding is presented. The bowing of thereference ladder due to interaction with the input stages isanalyzed, and analytical models are derived. 相似文献
78.
针对传统单峰谱插值谐波测量算法在非同步采样时由于频谱泄漏造成测量精度不足的问题,提出一种基于频率补偿的改进算法,并且分析传统插值算法的测量误差,改进了修正公式。该算法通过三个步骤实现,第一,基于汉宁窗插值校正频率,然后利用相对频偏进行频率补偿得到准同步化序列。第二,采用准同步化序列基于汉宁窗再次插值校正频率,将两次计算得到的相对频偏相加用于修正频率,进而减轻频谱泄漏的影响。最后,为了提高幅值和相位的测量精度,利用准同步化序列基于平顶窗直接估计,无需推导反演公式。仿真实验结果表明,该算法的测量精度相比于传统的单峰谱插值算法提升显著,在噪声环境下相比于四谱线插值、相位差算法,该算法具有更高的精度和抗噪性能,验证了所提出算法的有效性和准确性。 相似文献
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Chi-Chang Wang 《International Communications in Heat and Mass Transfer》2005,32(10):1337-1349
This research discusses the impacts of the surface area that the wavy surface gets more than the flat plate upon the aerosol particle deposition. Starting from the full Navier–Stokes equation, the mathematical analysis takes the thermophoretic motion formed by the temperature gradient and the fluid thermal expansion into consideration, and converts the governing equations into the boundary layer equation by the simple coordinate transformation and non-similarity method, and then works out these equations by the Spline Alternating-Direction Implicit method (SADI). The numerical value result reveals that the average deposition effect of the wavy plate is greater than the flat plate and that the increasing rate is nearly equal to the value obtained by dividing the surface area that the wavy plate gets more than the flat plate by 2.2. 相似文献