The impact of block adaptive quantization algorithm on power-loss with SAR raw data

2015 ◽  
Author(s):  
Haojie Zhang ◽  
Jie Chen ◽  
Hongcheng Zeng ◽  
Wei Yang ◽  
Jingwen Li
Keyword(s):  
Power Loss ◽  
Raw Data ◽  
Adaptive Quantization ◽  
The Impact

scholarly journals An Improved BAQ Encoding and Decoding Method for Improving the Quantized SNR of SAR Raw Data

Sensors ◽  
2018 ◽  
Vol 18 (12) ◽  
pp. 4221
Author(s):  
Wei Ji ◽  
Xiaolan Qiu ◽  
Xuejiao Wen ◽  
Lijia Huang
Keyword(s):  
Power Loss ◽  
Signal To Noise Ratio ◽  
Practical Application ◽  
Scattering Mechanism ◽  
Echo Signal ◽  
Signal To Noise ◽  
Raw Data ◽  
Look Up Table ◽  
Adaptive Quantization ◽  
Simulation Results

When the original echo data of SAR are saturated for quantization, the performance of the commonly used block adaptive quantization (BAQ) algorithm will be degraded, which will degrade the imaging quality. This article proposes an improved Llody-Max codec method, which only needs to change the codec look-up table to get better quantization performance when the original echo is saturated. The simulation results show that the proposed method can reduce the quantization power loss, improve the echo signal-to-noise ratio (SNR), and reduce the influence of quantization saturation on the scattering mechanism of polarized SAR data, which have good practical application value.

scholarly journals In-Situ Measurement of Power Loss for Crystalline Silicon Modules Undergoing Thermal Cycling and Mechanical Loading Stress Testing

Energies ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 72
Author(s):  
Sergiu Spataru ◽  
Peter Hacke ◽  
Dezso Sera
Keyword(s):  
Thermal Cycling ◽  
Power Loss ◽  
Stress Testing ◽  
Series Resistance ◽  
Short Circuit ◽  
In Situ Measurement ◽  
Mechanical Degradation ◽  
Model Parameters ◽  
The Impact

An in-situ method is proposed for monitoring and estimating the power degradation of mc-Si photovoltaic (PV) modules undergoing thermo-mechanical degradation tests that primarily manifest through cell cracking, such as mechanical load tests, thermal cycling and humidity freeze tests. The method is based on in-situ measurement of the module’s dark current-voltage (I-V) characteristic curve during the stress test, as well as initial and final module flash testing on a Sun simulator. The method uses superposition of the dark I-V curve with final flash test module short-circuit current to account for shunt and junction recombination losses, as well as series resistance estimation from the in-situ measured dark I-Vs and final flash test measurements. The method is developed based on mc-Si standard modules undergoing several stages of thermo-mechanical stress testing and degradation, for which we investigate the impact of the degradation on the modules light I-V curve parameters, and equivalent solar cell model parameters. Experimental validation of the method on the modules tested shows good agreement between the in-situ estimated power degradation and the flash test measured power loss of the modules, of up to 4.31 % error (RMSE), as the modules experience primarily junction defect recombination and increased series resistance losses. However, the application of the method will be limited for modules experiencing extensive photo-current degradation or delamination, which are not well reflected in the dark I-V characteristic of the PV module.

scholarly journals Derivation of power loss factors to evaluate the impact of postcombustion CO2 capture processes on steam power plant performance

2011 ◽  
Vol 4 ◽  
pp. 1385-1394 ◽  
Author(s):  
Sebastian Linnenberg ◽  
Ulrich Liebenthal ◽  
Jochen Oexmann ◽  
Alfons Kather
Keyword(s):  
Power Plant ◽  
Co2 Capture ◽  
Power Loss ◽  
Plant Performance ◽  
Steam Power ◽  
Steam Power Plant ◽  
The Impact ◽  
Loss Factors

scholarly journals Slow Decay of Impact in Equity Markets

2015 ◽  
Vol 01 (02) ◽  
pp. 1550007 ◽  
Author(s):  
X. Brokmann ◽  
E. Sérié ◽  
J. Kockelkoren ◽  
J.-P. Bouchaud
Keyword(s):  
Power Law ◽  
Equity Markets ◽  
Impact Model ◽  
Market Impact ◽  
Temporal Dependence ◽  
Raw Data ◽  
Slow Decay ◽  
First Approximation ◽  
Information Contents ◽  
The Impact

Using a proprietary dataset of meta-orders and prediction signals, and assuming a quasi-linear impact model, we deconvolve market impact from past correlated trades and a predictable return component to elicit the temporal dependence of the market impact of a single daily meta-order, over a 10-day horizon in various equity markets. We find that the impact of single meta-orders is to a first approximation universal and slowly decays to zero (or to a small value), possibly as a power-law. We show that autocorrelated order-flows and trade information contents fully accounts for the apparent plateau observed in the raw data. We discuss the possible bias introduced by the quasi-linear assumption.

scholarly journals Numerical Simulation Investigation on the Windage Power Loss of a High-Speed Face Gear Drive

Energies ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 2093 ◽  
Author(s):  
Yu Dai ◽  
Feiyue Ma ◽  
Xiang Zhu ◽  
Jifu Jia
Keyword(s):  
Power Loss ◽  
High Speed ◽  
Outer Radius ◽  
Face Gear ◽  
Optimal Distance ◽  
Inner Radius ◽  
Common Goals ◽  
Cfd Method ◽  
Gear Drives ◽  
The Impact

Reducing the energy consumption and improving the efficiency of high-speed transmission systems are increasingly common goals; the windage power loss is not negligible in these methods. In this work, the multi-reference frame (MRF) and periodic boundary conditions (PBC) based on the computational fluid dynamics (CFD) method were adopted to investigate the windage phenomena of a single face gear with and without a shroud, and the impact of the gear speed on the windage power loss was analyzed. Furthermore, the effects on the distribution of static pressure due to the distances between the shroud and the gear body in different directions, including the outer radius direction, the inner radius direction, and the addendum direction were investigated. The results indicate that the gear speed significantly affected the windage loss, as the higher the gear speed was, the greater the windage power loss. Additionally, the shroud could effectively reduce the windage power loss, where the optimal distance from the addendum to the shroud was not the minimum distance; however, for the distances from the shroud to the inner radius and the outer radius, the smaller the distance was, the smaller the windage loss. The results can provide a theoretical basis and technical reference for reducing the windage power loss of various face gear drives.

Outliers in L2 Research in Applied Linguistics: A Synthesis and Data Re-Analysis

2020 ◽  
Vol 40 ◽  
pp. 26-55 ◽  
Author(s):  
Christopher Nicklin ◽  
Luke Plonsky
Keyword(s):  
Phase I ◽  
Relative Effectiveness ◽  
Reaction Time Data ◽  
Future Research ◽  
Time Data ◽  
Two Phase ◽  
Raw Data ◽  
Study Results ◽  
Using Data ◽  
The Impact

AbstractData from self-paced reading (SPR) tasks are routinely checked for statistical outliers (Marsden, Thompson, & Plonsky, 2018). Such data points can be handled in a variety of ways (e.g., trimming, data transformation), each of which may influence study results in a different manner. This two-phase study sought, first, to systematically review outlier handling techniques found in studies that involve SPR and, second, to re-analyze raw data from SPR tasks to understand the impact of those techniques. Toward these ends, in Phase I, a sample of 104 studies that employed SPR tasks was collected and coded for different outlier treatments. As found in Marsden et al. (2018), wide variability was observed across the sample in terms of selection of time and standard deviation (SD)-based boundaries for determining what constitutes a legitimate reading time (RT). In Phase II, the raw data from the SPR studies in Phase I were requested from the authors. Nineteen usable datasets were obtained and re-analyzed using data transformations, SD boundaries, trimming, and winsorizing, in order to test their relative effectiveness for normalizing SPR reaction time data. The results suggested that, in the vast majority of cases, logarithmic transformation circumvented the need for SD boundaries, which blindly eliminate or alter potentially legitimate data. The results also indicated that choice of SD boundary had little influence on the data and revealed no meaningful difference between trimming and winsorizing, implying that blindly removing data from SPR analyses might be unnecessary. Suggestions are provided for future research involving SPR data and the handling of outliers in second language (L2) research more generally.

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