Abstract
Urban sewer system management is challenging due to its higher vulnerability to flooding caused by rapid urbanization and climate change. For local decision-makers, storm water management is ...essential for urban planning and development. Therefore, the main objective of this study is to develop a numerical model for the sewerage network of the central catchment area of Algiers since it has experienced frequent overflows during the winter season. For this purpose, to model the sewerage networks, the model was built by coupling ArcGIS with MIKE URBAN. Its calibration and validation were performed using real-time measurements with a time step of 15 min. The model was evaluated by several statistical indicators, such as the coefficient of determination (R2), Nash–Sutcliffe efficiency (NSE), root mean square error (RMSE), and percent bias (PBIAS). The model results showed acceptable model performance, with an NSE superior to 0.50, R2 of approximately 0.63, RMSE of 7%, and PBIAS of 10% during the validation of the model. The performance parameters prove the reliability of the developed model. The employed model can be applied in other regions and could be helpful for policymakers and managers to improve flood mitigation measures based on the model prediction of the sewerage network.
Any hydro-meteorology variable includes different components, in general, such as periodicity, trend, possibly jump, and uncertain stochastic parts. Among these, the trend analysis gained importance ...in the last three decades due to global warming and climate change effects. The literature is full of monotonic trend applications by taking into consideration trend analysis methodologies such as Mann–Kendall trend identification, Sen trend slope calculation, and Şen innovative trend analysis (ITA). It is more important in practical studies to deal with less than one-year durations to assess the possible trend pieces for better practical uses such as agricultural productivity purposes. In this paper, a new concept is applied, known as the innovative polygon trend analysis (IPTA), to assess the trend component transitions between two successive months. The application of the methodology is presented for the coastal region of northeast Algerian precipitation records. The emanated results from this study provided information that El Taref station has the most unstable precipitation behavior among all the meteorology stations in the study area, moving from a month to another rather very unsystematically; whereas other meteorology stations have systematic movement from a month to the subsequent one.
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•An inclusive DEA-based approach to compute a Composite Water Quality Index (CWQI).•CWQI fully ranks water sources via observed physicochemical factors.•OWA operator incorporates ...practical water treatment conditions into CWQI.•k-Means clustering analysis used to derive water quality ranges.•The new methodology is applied on 47 dams located in the Tellian region, Algeria.
This paper introduces a new index, identified as Composite Water Quality Index (CWQI), for assessing water quality. The novelty of CWQI is rooted in the practical significance of the methodological approach that is developed for its computation. The CWQI is computed within an inclusive framework that integrates data envelopment analysis (DEA) Cross Efficiency (CE) and the Ordered Weighted Averaging (OWA) operator, using Optimistic Closeness Values (OCVs) as input variables. The OCV, which measures the potential of a water quality parameter to reach its best quality status, sets a solid preliminary ground for the assessment process. The DEA-CE approach enables a collective evaluation of the water quality, which bestows more inclusiveness on the quality assessment process and, hence, more robustness of the CWQI. The OWA operator extends the standard role of CWQI, as solely a water quality measurement device, to incorporate the practical conditions of water treatment for future decision plans. The new methodology has been applied on a sample of 47 dams, described with 10 physicochemical parameters, located in Northern Algeria. Adopting a wide range of water treatment conditions, the results reveal “Kissir” and “Bougara” as the best and the worst water sources, respectively. Meanwhile, the ranking patterns of the dams are found almost the same. The k-means clustering identified the Oranie–Chott–Chergui (OCC) basin as the poorest water quality zone and Algerois–Hodna–Sommam (AHS) basin as the best.
Flood magnitude, frequency and intensity are bound to increase in many parts of the world due to global warming and its consequent effect as climate change impacts. The main purpose of this paper is ...to apply the classical probable maximum precipitation and probable maximum flood methodologies leading to a new concept of risk level charts, which provide hydrograph time to peak probable maximum discharge after the beginning of precipitation, base time and peak discharge values. Dimensionless hydrograph methodology is employed for flood hydrograph analysis. The applications of probable maximum precipitation and probable maximum flood methodologies are presented for Algerian meteorology stations’ annual maximum daily precipitation amounts from 23 different locations at Hodna drainage basin in the north-eastern of Algeria. Classical probable maximum precipitation frequency factor is obtained for each meteorology station record, which are then converted to pointwise probable maximum flood amounts that are helpful to construct practically applicable flood charts. A new relationship is provided between probable maximum precipitation and the frequency factor for the study area. The efficiency factor is calculated for each station to understand whether there is a further possibility for extreme precipitation, and consequent flood occurrences.
Current hole matching pixel detector (HMPD) collimators for SPECT imaging exist in two configurations: one hole per pixel (1HMPD) or four holes per pixel (4HMPD). The aim of this study was to assess ...the performance of a dual-layer collimator made by stacking up these two collimator types (1H/4HMDP) for low- and medium energy gamma emitters.
. Analytical equations describing geometrical efficiency and full width at half maximum (FWHM) of the 1H/4HMDP collimator were derived. In addition, a fast dedicated Monte Carlo (MC) code neglecting scattering and designed for the collimator geometry was developed to assess the collimator's point spread function and to simulate planar and SPECT acquisitions.
A relative agreement between analytical equations and MC simulations better than 3% was observed for the efficiency and for the FWHM. The length of the two layers was optimized to get the best spatial resolution while keeping the geometrical efficiency equal to that of the 45 mm length 1HMPD collimator. An optimized combination of the 1H/4HMPD configuration with respective hole lengths of 20 and 13 mm has been derived. For source-collimator distances above 5 cm and equal collimator geometrical efficiency, the spatial resolution of this optimal 1H/4HMDP collimator supersedes that of the 45 mm length 1HMPD collimator, and that of the 19.1 mm length 4HMPD collimator. This improvement was observed in simulations of bar phantom planar images and of hot rods phantom SPECT. Remarkably, the spatial resolution was preserved along the whole radial range within the Jaszczak phantom.
The 1H/4HMDP collimator is a promising solution for CZT SPECT imaging of low- and medium energy emitters.
The study aimed to determine the areas of future urban expansion in Bordj Bou Arreridj, Algeria, by using multi-criteria analysis for decision-making. First, the future population was estimated to ...calculate the area we would need for the horizon of 2041AD. Second, criteria that contribute to determining the best areas for future expansion were selected based on recent research literature. Six factors were adopted: (industrial areas, agricultural lands, urban areas, road network, slopes, and hydrographic network). Third, the analytic hierarchy process (AHP) was used to make a comparison of the previous standards and to extract the weights. Fourth, translating the results obtained in the (QGIS) program and extracting a digital map showing areas suitable for future urban expansion according to three classifications (high spatial suitability, acceptable, and low). The results showed that the areas with high spatial suitability it densely distributed in the northeastern and western directions with an area of 12.42 km² or 23%. It is considered an insufficient area to meet the future need of 2041 AD, which amounted to 14.20 km². Followed by areas with acceptable suitability distributed in four geographical directions, occupying an area of 15.67 km² or 35%, which is a sufficient area and can be placed as a balance to fill the deficit. While the areas with low suitability densely distributed in the east-west sides, with an area of 16.26 km² or 37%. The research proved that the integration between (AHP) and (GIS) technologies have an important role in helping decision-makers identify suitable areas for future expansion, reduce the problems of random urbanization and create a homogeneous sustainable environment. Urban development in the future.
Significant progress has been achieved in the design of pixelated CZT detectors dedicated to cardiac and breast SPECT imaging. However, their detector geometry and associated collimators' design have ...limited their clinical use. The aim of this work is to determine the best combination between a large pixelated CZT detector and parallel-hole collimator that can provide high spatial resolution at low injected activity with low-energy radiotracers. Our proposed combination resulted in the design of a novel four-hole matched pixel detector (4-HMPD) configuration. Our novel 4-HMPD design based on large pixelated CZT detector was firstly compared to the standard one-hole matched pixel detector (1-HMPD) configuration using Monte Carlo simulation. We have also predicted the influence of pixel size, interpixel gap and source-to-collimator distance on the basis of resulting spatial resolution, sensitivity and crosstalk events fraction for three collimator hole lengths for Tc-99m (140 keV) . Thereafter, we used the same detector and collimator settings of the 1-HMPD configuration as constructed with the D-SPECT camera module (Redlen Technologies, BC, Canada) for our 4-HMPD design to compare the performance of the two configurations. Our preliminary results showed that a large pixel size, a small interpixel gap and a small collimator hole length increased significantly the sensitivity at the detriment of spatial resolution. The performance comparison between the 4-HMPD and the 1-HMPD configurations demonstrated an improved reconstructed spatial resolution (by a factor two), higher contrast with the large sphere of the modified Jaszczak phantom (from 63.1% to 39.1%), clear appearance of cold spheres (>14 mm diameter) and the cold cylinders (>11.1 mm diameter). The crosstalk events fraction varied from 8.5% to 12.8%. Our novel detector/collimator combination allows less electronic readout complexity, less crosstalk events between pixels and twofold increase in septal thickness resulting in low septal penetration compared to the classical 1-HMPD configuration. It also showed the highest enhancement in terms of spatial resolution even in cases of low sensitivity with less injected activity, and outperformed the performance of existing conventional NaI (TI) crystal-based systems.
This study aims to examine three machine learning (ML) techniques, namely random forest (RF), LightGBM, and CatBoost for flooding susceptibility maps (FSMs) in the Vietnamese Vu Gia-Thu Bon (VGTB). ...The results of ML are compared with those of the rainfall-runoff model, and different training dataset sizes are utilized in the performance assessment. Ten independent factors are assessed. An inventory map with approximately 850 flooding sites is based on several post-flood surveys. The inventory dataset is randomly split between training (70%) and testing (30%). The AUC-ROC results are 97.9%, 99.5%, and 99.5% for CatBoost, LightGBM, and RF, respectively. The FSMs developed by the ML methods show good agreement in terms of an extension with flood inundation maps developed using the rainfall-runoff model. The models' FSMs showed 10-13% of the total area to be highly susceptible to flooding, consistent with RRI's flood map. The FSMs show that downstream areas (both urbanized and agricultural) are under high and very high levels of susceptibility. Additionally, different sizes of the input datasets are tested to determine the least number of data points having acceptable reliability. The results demonstrate that the ML methods can realistically predict FSMs, regardless of the number of training samples.
The electrode wire feeding mechanism (EWFM) is a closed-loop system that is commonly utilized in power-controlled arc welding machines to achieve better performance for different electrode wire ...diameters. This study presents parameters self-tuning method based on RBF neural network for active disturbance rejection controller (ADRC) of a welding EWFM and establishes a real-time testing system based on the dSPACE platform. First, an ADRC control strategy is developed to enhance the tracking performance and robustness of a welding EWFM in a multi-source disturbance environment. Second, an RBF-based parameters tuning method is provided to correctly determine and adjust the gains of the suggested ADRC regulator. Finally, to confirm the considered strategy, the real-time tests are conducted. The findings demonstrate that the suggested ADRC regulator with RBF-based gains tuning algorithm has a considerable disturbance rejection capability, small overshoot, fast response, and high precision which can improve the stability and quality of the arc welding process.
Grid-integrated photovoltaic (PV) systems hold significant promise for sustainable energy production. However, these systems often struggle with maintaining energy quality and stability in the face ...of fluctuating conditions. To address these challenges, this study proposes the use of fractional-order integral sliding mode control (FO-ISMC) for grid-connected PV systems. The system comprises solar panel arrays, a DC/DC boost converter with its controller, and a three-phase inverter integrated into the utility grid. The primary goals of this study are to maximize power extraction from the PV system and to regulate system currents, thereby improving effectiveness and power quality. The proposed method is further refined using the particle swarm optimization (PSO) algorithm to fine-tune parameter settings. By optimizing the command gains of the FOI-SMC, the PSO algorithm enhances system performance and stability. Leveraging fractional-order and integral terms provides the control signal with additional degrees of freedom, enhancing system performance in the presence of internal and external disturbances. Simulation results demonstrate the effectiveness of the proposed controller compared to the classical controller, where in the case of Irradiation taking the value of 500 W/m2, the proposed strategy reduced the values of constant voltage, active power, and reactive power by percentages estimated at 88.18%, 90%, and 70%, respectively, compared to the traditional strategy. Also, the overshoot value of active power was reduced in all completed cases compared to the traditional strategy by percentages estimated at 53.57%, 66.66%, and 65%, respectively. The proposed strategy reduced the response time of reactive power in all cases compared to the traditional strategy by percentages estimated at 58.59%, 28.80%, and 75%, respectively. These ratios show the high performance of the proposed control in improving the characteristics of the studied system compared to traditional control based on PI control.
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