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42.
Essam Sharaf El Din Yun Zhang Alaeldin Suliman 《International journal of remote sensing》2017,38(4):1023-1042
The deterioration of surface water quality occurs due to the presence of various types of pollutants generated from human, agricultural, and industrial activities. Thus, mapping concentrations of different surface water quality parameters (SWQPs), such as turbidity, total suspended solids (TSS), chemical oxygen demand (COD), biological oxygen demand (BOD), and dissolved oxygen (DO), is indeed critical for providing the appropriate treatment to the affected waterbodies. Traditionally, concentrations of SWQPs have been measured through intensive field work. Additionally, quite a lot of studies have attempted to retrieve concentrations of SWQPs from satellite images using regression-based methods. However, the relationship between SWQPs and satellite data is complex to be modelled accurately by using regression-based methods. Therefore, our study attempts to develop an artificial intelligence modelling method for mapping concentrations of both optical and non-optical SWQPs. In this context, a remote-sensing framework based on the back-propagation neural network (BPNN) is developed for the first time to quantify concentrations of different SWQPs from the Landsat8 satellite imagery. Compared to other methods, such as Support Vector Machine, significant coefficients of determination (R2) between the Landsat8 surface reflectance and concentrations of SWQPs were obtained using the developed Landsat8-based-BPNN models. The resulting R2 values were 0.991, 0.933, 0.937, 0.930, and 0.934 for turbidity, TSS, COD, BOD, and DO, respectively. Indeed, these findings indicate that the developed Landsat8-based-BPNN framework is capable of developing highly accurate models for retrieving concentrations of different SWQPs from the Landsat8 imagery. 相似文献
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Trend Assessment by the Innovative-Şen Method 总被引:1,自引:0,他引:1
İsmail Dabanlı Zekai Şen Mehmet Öner Yeleğen Eyüp Şişman Bülent Selek Yavuz Selim Güçlü 《Water Resources Management》2016,30(14):5193-5203
Hydro-meteorological time series may include trend components mostly due to climate change since about three to four decades. Trend detection and identification in a better and refined manner are among the major current research topics in water resources domain. Even though different methodologies can be found for trend detection in literature, two well-known procedures are the Mann-Kendall (MK) trend test and recently innovative-?en trend method, which provides different aspects of the trend. The theoretical basis and application of these two methods are completely different. The MK test gives a holistic monotonic trend without any categorization of the time series into a set of clusters, but the innovative-?en method is based on cluster and provides categorical trend behavior in a given time series. The main purpose of this paper is to provide important differences between these two approaches and their possible similarities. The applications of the two approaches are given for hydro-meteorological records including relative humidity, temperature, precipitation and runoff from Ergene drainage basin in the north-western part of Turkey. It is observed that although MK trend test does not show significant trend almost in all the cases, the innovative-?en approach yields trend categorizations as “very low”, “low”, “medium” “high” and “very high”, which should be taken into consideration in future flood (“very high”) and drought (“very low”) studies. 相似文献
45.
Aysel Buyuksagis Meltem Dİlek 《Protection of Metals and Physical Chemistry of Surfaces》2019,55(6):1182-1194
Protection of Metals and Physical Chemistry of Surfaces - The corrosion inhibition and adsorption characteristics of the extract obtained from the plant Papaver somniferum L. (PSL) by... 相似文献
46.
Theoretical calculation simulation studies of ABV nuclear reactor coupled with desalination system
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Salah Ud‐Din Khan Syed Noman Danish Sajjad Haider Shahab Ud‐Din Khan 《国际能源研究杂志》2015,39(11):1554-1563
In this paper, research has been conducted on the floating type nuclear power plant named as ABV reactor which is designed for district heating, power, and sea water desalination by OKBM facility at Russia. This reactor was tested under different thermal loads during the designing phase, and three modules have been investigated. Theoretical calculations and simulation studies have been performed on these three modules having specifications as ABV‐6M with 47MWth, ABV‐6 with 38MWth, and ABV‐3 with 18MWth.The results obtained from these modules have been calculated mathematically and verified by simulation. We have compared the originally derived data of ABV desalination system with our theoretical and simulation analysis. The results from two desalination techniques including RO and RO + MED have been calculated and are presented in this paper with details. The results obtained from both analysis show that the efficiency of ABV nuclear reactor desalination system increases with the decrease in corresponding water cost ratio. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
47.
Neural Computing and Applications - The use of games in daily life, especially in education, has been in an incline during the COVID-2019 pandemic. Thus, game-based learning environments have... 相似文献
48.
Neural Computing and Applications - In this paper, a mini unmanned aerial vehicle (UAV) is planned to be used in applications such as spraying pesticide and weed control in agricultural areas.... 相似文献
49.
Korkanç Mustafa İnce İsmail Hatır M. Ergün Tosunlar M. Bahadır 《Bulletin of Engineering Geology and the Environment》2021,80(4):3053-3063
Bulletin of Engineering Geology and the Environment - The aim of this study is to determine the extent of deterioration of the limestone on which the İvriz rock monument is engraved. This... 相似文献
50.
In this paper, a novel system has been developed for plasma disruption conditions followed by downward vertical displacement. During the disruption, size and orientation of plasma decreases, which gives the halo current circulated around each contacting point in radial as well as in poloidal directions. Therefore, a new mathematical model has been developed, which gives the interaction forces of halo current, vertical, and radial plasma dynamical behavior (linear and nonlinear). This theoretical approach showed that the tokamak plasma has two connecting points in order to distinguish between the stable and unstable position. This model can particularly give the magnetic field change points and changing of flux, which are more convenient in order to discuss the static and tilting position of plasma behavior. Numerical techniques have been calculated in terms of plasma dynamical behavior, that is, Electromagnetic/plasma, Vertical Displacement Event (VDE) stages, and initial interaction between the forces under specific time interval. The objective of the research is to developed theoretical and computational model in order to investigate the dynamical behavior of plasma under disruption conditions. This is the novel method, and no work has been reported so far. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献