- 标题
- 摘要
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- 实验方案
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Treatment of sanitary landfill leachate by the combination of photo-Fenton and biological processes
摘要： In this work, the pollutant reduction performance in landfill leachate by combining both photo-Fenton and biological processes was investigated. First, conventional biological treatment was performed, consisting of a decantation process, with centrifugation at 5000 rpm for 15 min, followed by the biological process conducted at 2.36 ± 0.1 mg mg?1 (BOD5/MLSS) and 0.571 ± 0.04 vvm (L L?1 min?1) for 40 h. At the same time, in the application of the photo-Fenton process, a central composite rotatable design (CCRD) was applied to evaluate the effect of main process variables. The quadratic models of chemical oxygen demand (COD) and 5 days biological oxygen demand (BOD5) removal were proposed and validated, being separately used as objective functions during the search for optimal operating conditions. After the application of the conventional biological process, removals of 87 ± 2% and 84 ± 2% were obtained for COD and BOD5, respectively. For the photo-Fenton process under optimum conditions (3400 mg H2O2 L?1, 80 mg Fe2? L?1, pH = 2.40 and 120 min), removals of 89 ± 3% COD and 75 ± 1% BOD5 were obtained. However, both processes did not meet effluent discharge standards. So, the optimized photo-Fenton process was then combined with the biological process, performed for 150 h with 1.571 ± 0.06 vvm and 4.41 ± 0.3 mg mg?1 (BOD5/MLSS). With the combined process, it was possible to treat an effluent with high organic load, achieving a removal of 98% COD and BOD5 and meeting the restrictive standards of release in recipient water bodies.
关键词： Toxic effluent,Processes combination,Biodegradability,Processes performance assessment
更新于2025-09-23 15:23:52
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Multi-scale fidelity measure for image fusion quality assessment
摘要： Image fusion is considered an effective enhancing methodology widely included in high-quality imaging systems. Nevertheless, like other enhancing techniques, output quality assessment is made within small sample subjective evaluation studies which are very limited in predicting the human-perceived quality of general image fusion outputs. Simple, blind, universal and perceptual-like methods for assessing composite image quality are still a challenge, partially solved only in particular applications. In this paper, we propose a fidelity measure, called MS-QW with two major characteristics related to natural image statistics framework: a multi-scale computation and a structural similarity score. In our experiments, we correlate the scores of our measure with subjective ratings and state of art measures included in the 2015 Waterloo IVC multi-exposure fusion (MEF) image database. We also use the measure to rank correctly the classical general fusion methods included in the Image Fusion Toolbox for medical, infra-red and multi-focus image examples. Moreover, we study the scores variability and statistical discrimination power with the TNO night vision database using the Friedman test. Finally, we define a new leave one out procedure based on our fidelity measure that selects the best subset of images (within a collection of distorted and unregistered cellphone type images) that provides a defect-free composite output. We exemplify the procedure with the fusion of a collection of images from Latour and Van Dongen paintings suffering from glass highlights and speckle noise, among other artifacts. The proposed multiscale quality measure MS-QW demonstrates improvement over the previous single-scale similarity measures towards a fidelity assessment between quantitative image fusion quality metrics and human perceptual qualitative scores.
关键词： structural similarity,statistical performance assessment,high quality photographs of paintings,multi-scale measures,image fusion quality assessment
更新于2025-09-19 17:15:36
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An effective maximum power point tracker for partially shaded solar photovoltaic systems
摘要： The photovoltaic (PV) systems should operate at a maximum power point (MPP) to extract the maximum possible output power with high tracking efficiency under various operating conditions This paper discusses a new maximum power point tracking (MPPT) technique to extract the peak power from the PV panel/array during partial shaded conditions (PSCs). The proposed algorithm is based on bio-inspired Whale Optimization (WO) with reinitialization process when the PV system is subjected to change in shading pattern, and the algorithm tries to locate the global peak (GP) with a high convergence rate and high tracking efficiency. The proposed algorithm eliminates the computational burden faced by the hybrid MPPT algorithms as discussed in various literature and reduces the power oscillation during the change in operating conditions. The proposed technique is modeled and simulated under different test conditions using MATLAB/Simulink software. The performance of the proposed technique is compared with conventional perturb and observation (PO), Grey Wolf Optimization (GWO) and hybrid GWO (HGWO) techniques in terms of tracking time and tracking efficiency and the simulation result proves that WO technique displays high tracking efficiency (>95%) and less convergence time (<0.15sec) under PSCs with less power oscillations. Moreover, the performance assessment is carried out in terms of mismatching loss, fill factor, and relative power loss/gain.
关键词： Partial shading,Performance assessment,Global peak,WO,Convergence time,MPPT
更新于2025-09-19 17:13:59
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Artificial neural network based assessment of grid-connected photovoltaic thermal systems in heating dominated regions of Iran
摘要： In this paper, an artificial neural network (ANN) is developed to assess hybrid photovoltaic thermal (PVT) systems for grid-connected (GC) electricity generation, space heating and domestic hot water providing in heating dominated regions of Iran. To do so, monthly and annual performance of a 5 kWp GCPVT system is simulated for a single-family house. The simulation results show that the GCPVT system is very promising whereas the annual yield factor varies from 1506 kWh/kWp to 1891 kWh/kWp. Also, an appropriate solar fractions for covering hot water are achieved in a range from 74.5% to 49.4%. A multilayered perceptron feed-forward neural network which is trained by Levenberg-Marquardt algorithm is used to predict AC electrical energy and solar thermal output of the GCPVT system. The developed ANN is based on global horizontal irradiance, ambient temperature, ambient relative humidity and wind speed as inputs. The proposed configuration of ANN presents a high accuracy in predicting output energy of the GCPVT system according to minimum mean square error and maximum correlation coefficient. Analysis of variance is performed to determine the significant control parameters influencing the output energy of the GCPVT system.
关键词： Solar heating,AC electricity,Grid-connected PVT,Artificial neural network,Performance assessment
更新于2025-09-19 17:13:59
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Reliable long-term performance assessment of commercial photovoltaic modules tested under field conditions over 5 years
摘要： Due to their scalability and global abundance of sunlight, photovoltaic panels are a promising option as a renewable energy source. Implementation of photovoltaic technologies on a large scale requires a careful business-case assessment, aimed at the selection of the technological option most appropriate for the local conditions in terms of long-term performance. For this purpose, five types of modules representative of current options on the market were tested under field conditions for five years at a test facility in Germany. The degradation rates of module performance were computed from the obtained photovoltaic power normalized by both recorded and modeled solar irradiance. The results emphasize the relevance of using modeled irradiance data in addition to recorded solar irradiance in order to extract reliable degradation rates. The available methodological tools still have to be adapted to every dataset for the most accurate result. Eventually, robust degradation rates were extracted from experimental power data, based on modeled clear-sky irradiance, and a combination of aggregation and regression strategies. The results show distinctive degradation behaviors of the five available commercial photovoltaic modules in response to the local conditions.
关键词： performance assessment,photovoltaic modules,field conditions,degradation rates,solar irradiance
更新于2025-09-16 10:30:52