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Quantifying Airborne Lidar Bathymetry Quality-Control Measures: A Case Study in Frio River, Texas
摘要： Airborne Lidar Bathymetry (ALB) is an advanced and effective technology for mapping water bodies and measuring water depth in relatively shallow inland and coastal zones. The concept of using light beams to detect and traverse water bodies has been around since the 1960s; however, its popularity has increased significantly in recent years with the advent of relatively affordable hardware, supplemented with potent software applications to process and analyze resulting data. To achieve the most accurate final product, which is usually a digital elevation model (DEM) of the bottom of a water body, various quality-control (QC) measures are applied during and after an airborne mission. River surveys, in particular, present various challenges, and quantifying the quality of the end product requires supplemental surveys and careful analysis of all data sets. In this article, we discuss a recent ALB survey of the Frio River in Texas and summarize the findings of all QC measures conducted. We conclude the article with suggestions for successful ALB deployments at similar survey locations.
关键词： quality management,environmental conditions,uncertainties,Lidar bathymetry
更新于2025-09-23 15:22:29
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[IEEE 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Sozopol, Bulgaria (2019.9.6-2019.9.8)] 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Revision of GUM: the suggested alhorythm for processing measurment results
摘要： The main requirements for the revised GUM are considered. The proposed algorithm for processing measurement results is given. Criteria for compliance with the listed requirements are described. Methods for processing the measurement results with a nonlinear model are proposed.
关键词： estimate and standard uncertainty of the measurand,estimates and standard uncertainties of input quantities,correlation,expanded uncertainty,GUM revision
更新于2025-09-23 15:21:01
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Extraction of uncertain parameters of single-diode model of a photovoltaic panel using simulated annealing optimization
摘要： In this article, our goal is to improve the estimation of the parameters of solar photovoltaic models, we propose a method based on Simulated Annealing (SA) Optimization, the proposed algorithm takes into account the uncertainties of measurements. This algorithm consists of three steps such as the extraction of the parameters in a conventional manner, then the determination of the uncertainties of each parameter, finally the determination of the instantaneous parameters taking into account the results of the first two steps. For the validation of the proposed theoretical developments, the algorithm is applied to four different PV parameter estimation problems. The results obtained are compared with well-established algorithms to confirm its effectiveness. These comparisons have shown that the proposed method exhibits largely effective performances than existing methods in the literature.
关键词： Uncertainties measurements,Photovoltaic model,Simulated annealing optimization,Parameter estimation
更新于2025-09-23 15:19:57
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[IEEE 2019 Second International Conference on Advanced Computational and Communication Paradigms (ICACCP) - Gangtok, India (2019.2.25-2019.2.28)] 2019 Second International Conference on Advanced Computational and Communication Paradigms (ICACCP) - Design and Analysis of an $H_{\infty}$ Controller for a Single Phase Grid Connected Photovoltaic System with Parametric Uncertainties
摘要： This paper presents the synthesis of a H∞ controller for a single phase single stage grid connected photovoltaic (PV) system. The PV array is integrated to the utility grid using an inverter and a filter. Many a times while deriving the mathematical model of a system, there exists some discrepancy between the actual and the derived model of the system. Hence these uncertainties should be taken into account while deriving the controller for the system in order to achieve robust stability. Here the robust controller is designed taking into consideration the uncertainty in the parameters R, L and C. An appropriate state space model of the system is derived in order to facilitate the controller design with the perturbations. Here the controller is designed to as to meet the required objective of good reference tracking, disturbance rejection and robust stability. The controller design step involves the proper selection of weighing function and solution of the cost functions. The cost functions in this case are transfer function from exogenous inputs to output of the system to be minimized. It was observed that in order to achieve the required performance criteria the infinity norm of the cost functions should be less than unity. For this an h infinity optimization problem was solved using the hinfsyn command in MATLAB. A transient analysis was done in MATLAB simulation to see the effect of output disturbance on the system performance. A μ-synthesis was further done to test whether the system is robustly stable under parametric uncertainties. It was found that the designed controller is robustly stable, effectively track the reference input given to the system. Also the effect of disturbances in the system output is minimized.
关键词： Photovoltaic system,single-phase grid,H∞ controller,parametric uncertainties
更新于2025-09-12 10:27:22
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Simultaneous measurements of fuel concentration and temperature in gas jets by laser induced breakdown spectroscopy
摘要： Laser induced breakdown spectroscopy (LIBS) enables quantitative measurements of the equivalence ratio in flames, spray and gas jets. Although there are always considerable temperature differences between the calibrations and the LIBS measurements in flames and fuel jets, the temperature effects on LIBS were rarely mentioned and not corrected in the previous LIBS measurements. In this study, a novel method to simultaneously measure the equivalence ratio and the gas temperature by LIBS in a single laser shot is proposed. This method can correct the temperature effects based on the linear correlation between the peak intensity ratio (PIR) of atomic lines and the gas temperature. The PIR of H656/N746 and the full width at half maximum (FWHM) of H656 are employed to establish calibration curves with the equivalence ratio and the gas temperature, respectively, and both of calibrations show high coefficients of determination (R2). Then, the measurement accuracy and precision of the proposed method are discussed in detail. The total uncertainties in measurements of equivalence ratio and gas temperature are estimated by 5.6% and 5.8%, respectively. Finally, the simultaneous measurements of equivalence ratios and gas temperatures in methane jets at different positions and at different injection pressures are conducted. The comparison of equivalence ratios before and after correction of the temperature effects indicates that the accuracy of the fuel concentration measurements by LIBS would be remarkably degraded if the temperature variations were neglected.
关键词： Measurement uncertainties,Laser-induced breakdown spectroscopy (LIBS),Equivalence ratio,Gas temperature,Full width at the half maximum (FWHM)
更新于2025-09-12 10:27:22
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A Simple and Reliable Photovoltaic Forecast for Reliable Power System Operation Control
摘要： Recently various forecasting methods for photovoltaic (PV) generation have been proposed in the literature. However, these standard methods cannot be successfully and widely used in general due to the fact that they require access to specialized data that are not always and everywhere readily available in practice. Furthermore, prediction accuracy of such methods tends to deteriorate specially due to data scarcity. This paper proposes a simple and reliable PV forecasting method using machine learning and neural networks. Confidence interval (CI) results are specifically provided for the local supply-demand control as well as for the robust power system security. The proposed method uses only weather forecasting data that are provided by the Japan Meteorological Agency (JMA) and which is available to the public. The proposed method maintains a high level of accuracy by using real-time correlation data between the specific target and the neighboring areas. Multiple neural networks are constructed based on a weather clustering technique. It has been confirmed through extensive simulation results that the proposed method demonstrates robustness in prediction accuracy and CI effectiveness.
关键词： Confidence intervals,Local energy management,Neural networks,Uncertainties,PV forecasting
更新于2025-09-12 10:27:22
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Extraction of Uncertain Parameters of Double-Diode Model of a Photovoltaic Panel Using Simulated Annealing Optimization
摘要： In this article, our goal is to improve the estimation of the parameters of solar photovoltaic models by using the simulated annealing (SA) algorithm. The proposed approach takes into account the uncertainties of measurements. This approach consists of three steps. The ?rst is the extraction of the parameters in a conventional manner based on SA. Then, in order to reduce the search interval of parameters, we will determine the uncertainties of the measurements of each parameter. Finally, we will determine the instantaneous parameters, taking into account the results of the ?rst two steps. For the validation of proposed theoretical developments, the proposed approach is applied to two di?erent commercial solar panel parameter estimation problems (the monocrystalline solar module STM6-40/36 and the polycrystalline silicon cells photovoltaic module Sharp ND-R250A5). The results obtained are compared with well-established algorithms to con?rm its e?ectiveness. These comparisons have shown that the proposed method exhibits largely more e?ective performances than existing methods in the literature.
关键词： uncertainties,polycrystalline silicon cells,solar photovoltaic models,simulated annealing,monocrystalline solar module,parameter estimation
更新于2025-09-11 14:15:04
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[IEEE 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Paris, France (2018.7.8-2018.7.13)] 2018 Conference on Precision Electromagnetic Measurements (CPEM 2018) - Calculation of Voltage Reflection Coefficients of Coaxial Airlines and Evaluation of Their Measurement Uncertainties at SCL
摘要： This paper describes the use of a simple software tool developed by Standards and Calibration Laboratory (SCL) to calculate the voltage reflection coefficients (VRC) of coaxial airlines and evaluate their measurement uncertainties with Monte Carlo method. The results can be used to verify vector network analyzer before using it to take measurement.
关键词： Coaxial airlines,measurement uncertainties,voltage reflection coefficients,Monte Carlo method
更新于2025-09-10 09:29:36
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[IEEE 2018 10th International Conference on Wireless Communications and Signal Processing (WCSP) - Hangzhou, China (2018.10.18-2018.10.20)] 2018 10th International Conference on Wireless Communications and Signal Processing (WCSP) - Achievable Rate of Indoor THz Communication Systems with Finite-Bit ADCs
摘要： In this paper, the achievable rate of the downlink terahertz (THz) communication systems equipped with finite-bit analog-to-digital converters (ADCs) at user sides is investigated. Considering the array of subarray antenna structure, the hybrid precoding with the maximum ratio transmission (MRT) and zero-forcing (ZF) precoding are applied at the baseband. The closed-form expression of the lower bound of the achievable rate is derived when the number of subarray antennas goes to infinity. It is shown that the coarse quantization distortion cannot be ignored in large antenna subarray regime. On the other hand, the rate loss caused by the phase uncertainties can be negligible in large subarray antenna regime. Overall, the impact of quantized receivers on the performance of indoor THz communication systems is characterized.
关键词： finite-bit ADCs,hybrid precoding,Terahertz communication,phase uncertainties,achievable rate
更新于2025-09-04 15:30:14
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Reduction of Forced Outages in Islanded Microgrids by Compensating Model Uncertainties in PV Rating and Battery Capacity
摘要： Energy management systems for islanded microgrids often rely on predictions of energy availability and usage. Such predictions can be used to plan actions, such as shedding non-essential loads, so that critical loads continue to be served. However, uncertainties in the prediction models may lead to incorrect decisions, and subsequently jeopardize reliable operation of the microgrid. For a photovoltaic (PV) and battery based microgrid, uncertainties in the PV rating and the battery capacity model parameters can lead to otherwise avoidable outages. In this paper, techniques have been developed to identify and compensate for such model uncertainties. The approach uses differences between the actual and predicted data sequences to determine compensation factors to improve prediction accuracy. The developed techniques account for operating condition changes automatically, and no additional sensors are needed for their implementation. The method has been evaluated using data from rooftop irradiance and temperature sensors and the corresponding forecasts. It has been shown that the proposed techniques can improve the accuracy of the predictions and hence lead to more effective energy management decisions. Together with a pre-emptive load shedding strategy, the total outage time of the microgrid can be shortened by as much as 11% for the chosen scenario.
关键词： Energy management,photovoltaic systems,prediction model uncertainties,microgrids
更新于2025-09-04 15:30:14