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51.
ABSTRACT

Developing a general framework to capture the complexities associated with the non-linear and adaptive nature of farmers facing water resources scarcity is a challenging problem. This paper integrates agent-based modelling (ABM) and a data mining method to develop a hybrid socio-hydrological framework to provide future insights for policy-makers. The data associated with the farmers’ main characteristics were collected through field surveys and interviews. Afterwards, the association rule was employed to discover the main patterns representing the farmers’ agricultural decisions. The discovered patterns were then used as the behavioural rules in ABM to simulate the agricultural activities. The proposed framework has been was applied to explore the interactions between agricultural activities and the main river feeding the Urmia-Lake, Iran. The outcomes indicate that farmers’ acquisitive traits and belongings have significant impacts on their socio-hydrological interactions. The reported values of the efficiency criteria may support the satisfactory performance of the proposed framework.  相似文献   
52.
Matching pursuit belongs to the category of spectral decomposition approaches that use a pre-defined discrete wavelet dictionary in order to decompose a signal adaptively. Although disengaged from windowing issues, matching point demands high computational costs as extraction of all local structure of signal requires a large size dictionary. Thus in order to find the best match wavelet, it is required to search the whole space. To reduce the computational cost of greedy matching pursuit, two artificial intelligence methods, (1) quantum inspired evolutionary algorithm and (2) particle swarm optimization, are introduced for two successive steps: (a) initial estimation and (b) optimization of wavelet parameters. We call this algorithm quantum swarm evolutionary matching pursuit. Quantum swarm evolutionary matching pursuit starts with a small colony of population at which each individual, is potentially a transformed form of a time-frequency atom. To attain maximum pursuit of the potential candidate wavelets with the residual, the colony members are adjusted in an evolutionary way. In addition, the quantum computing concepts such as quantum bit, quantum gate, and superposition of states are introduced into the method. The algorithm parameters such as social and cognitive learning factors, population size and global migration period are optimized using seismic signals. In applying matching pursuit to geophysical data, typically complex trace attributes are used for initial estimation of wavelet parameters, however, in this study it was shown that using complex trace attributes are sensitive to noisy data and would have lower rate of convergence. The algorithm performance over noisy signals, using non-orthogonal dictionaries are investigated and compared with other methods such as orthogonal matching pursuit. The results illustrate that quantum swarm evolutionary matching pursuit has the least sensitivity to noise and higher rate of convergence. Finally, the algorithm is applied to both modelled seismograms and real data for detection of low frequency anomalies to validate the findings.  相似文献   
53.
Although the effectiveness of best management practices (BMPs) in reducing urban flooding is widely recognized, the improved sustainability achieved by implementing BMPs in upstream suburban areas, reducing downstream urban floods, is still debated. This study introduces a new definition of urban drainage system (UDS) sustainability, focusing on BMP usage to enhance system performance after adaptation to climate change. Three types of hydraulic reliability index (HRI) plus robustness and improvability indices were used to quantify the potential enhanced sustainability of the system in a changing climate, together with a climate change adaptability index (CCAI). The sustainability of UDS for the safe conveyance of storm-water runoff was investigated under different land-use scenarios: No BMP, BMP in urban areas, and BMP inside and upstream of urban areas, considering climate change impacts. Rainfall–runoff simulation alongside drainage network modelling was conducted using a storm-water management model (US EPA SWMM) to determine the inundation areas for both base-line and future climatic conditions. A new method for disaggregating daily rainfall to hourly, proposed to provide a finer resolution of input rainfall to SWMM, was applied to a semi-urbanized catchment whose upstream runoff from mountainous areas may contribute to the storm-water runoff in downstream urban parts. Our findings confirm an increase in the number of inundation points and reduction in sustainability indices of UDS due to climate change. The results present an increase in UDS reliability from 4% to 16% and improvements in other sustainability indicators using BMPs in upstream suburban areas compared to implementing them in urban areas.  相似文献   
54.
The complex stream bank profiles in alluvial channels and rivers that are formed after reaching equilibrium has been a popular topic of research for many geomorphologists and river engineers. The entropy theory has recently been successfully applied to this problem. However, the existing methods restrict the further application of the entropy parameter to determine the cross-section slope of the river banks. To solve this limitation, we introduce a novel approach in the extraction of the equation based on the calculation of the entropy parameter (λ) and the transverse slope of the bank profile at threshold channel conditions. The effects of different hydraulic and geometric parameters are evaluated on a variation of the entropy parameter. Sensitivity analysis on the parameters affecting the entropy parameter shows that the most effective parameter on the λ-slope multiplier is the maximum slope of the bank profile and the dimensionless lateral distance of the river banks.  相似文献   
55.
Studia Geophysica et Geodaetica - We examine the potential of magnetic susceptibility measurements to discriminate different soil drainage classes in the Gandoman region, central Iran. Four soil...  相似文献   
56.
The present paper is an attempt to integrate a semi-automated object-based image analysis (OBIA) classification framework and a cellular automata-Markov model to study land use/land cover (LULC) changes. Land use maps for the Sarab plain in Iran for the years 2000, 2006, and 2014 were created from Landsat satellite data, by applying an OBIA classification using the normalized difference vegetation index, salinity index, moisture stress index, soil-adjusted vegetation index, and elevation and slope indicators. The classifications yielded overall accuracies of 91, 93, and 94% for 2000, 2006, and 2014, respectively. Finally, using the transition matrix, the spatial distribution of land use was simulated for 2020. The results of the study revealed that the number of orchards with irrigated agriculture and dry-farm agriculture in the Sarab plain is increasing, while the amount of bare land is decreasing. The results of this research are of great importance for regional authorities and decision makers in strategic land use planning.  相似文献   
57.
Soil erosion, a serious environmental problem, is a global challenge. Once a portion of a fertile soil is lost, it is very difficult to replace it, and this leads to decrease in crop production, damage to drainage networks, and siltation of dams and reservoirs. Human practices like intensive agriculture, overgrazing, and deforestation have intensified the rate of soil erosion all over the world. The Jhelum basin which forms the north-western part of the complex mountain system Himalayas is not only highly vulnerable to natural hazards like earthquakes, landslides, and floods but is also highly susceptible to soil erosion. There is an immediate need to device strategies to reduce adverse impacts of soil erosion and to conserve natural resources like soil, water, and forests by means of proper watershed management programs in the Himalayan region. The present study is carried out for eight upper watersheds of Jhelum basin, an area which are facing serious issues like boulder extraction, deforestation, and unplanned urbanization. The present work demonstrates the use of morphometry, land use, and slope coupled with the multicriteria analytical (MCA) framework to estimate the soil erosion susceptibility of these watersheds using Remote Sensing and Geographical Information System techniques. The present study revealed that out of eight upper watersheds, Arapal, Lidder, and Bringi fall in high priority and need immediate attention and measures to reduce soil erosion in the area. Sandran, Rembiara, and Romshii fall in medium priority. Kuthar and Vishav fall in the low-priority category and are least susceptible to soil erosion.  相似文献   
58.
Dehoo manganese deposit is located 52 km to the south of Zahedan in Sistan and Baluchestan Province, southeastern Iran. This deposit that lies in the central part of the Iranian Flysch Zone is lenticular in shape and lies above the micritic limestone-radiolarite cherts of the upper Cretaceous ophiolite unit. It is hosted within the reddish to brown radiolarite cherts and in places interlinks with them, so that the radiolarite chert packages play a key role for Mn mineralization in the region. Investigated ore-paragenetic successions and the geochemical characteristics of the Dehoo deposit were studied by means of major oxide, trace, and rare earth element (REE) contents that provide information as to the mineral origin. Strong positive correlations were found between major oxides and trace elements (Al2O3-TiO2, r = 0.95; TiO2-MgO, r = 0.94; Fe2O3-Al2O3, r = 0.90; MgO-Al2O3, r = 0.84; MgO-Fe2O3, r = 0.88; Fe2O3-TiO2, r = 0.91; Fe2O3-K2O, r = 0.74; Al2O3-K2O, r = 0.69; Al2O3-V, r = 0.72; TiO2-V, r = 0.73, and MgO-V, r = 0.69) that testify to the contribution of mafic terrigenous detrital material to the deposit. Chondrite-normalized REE patterns of all ore samples are characterized by negative Ce (0.06–0.15, average 0.10) and slightly positive Eu (0.29–0.45, average 0.36) anomalies. Based on ratios of Mn/Fe (average 56.23), Co/Ni (average 0.33), Co/Zn (average 0.38), U/Th (average 3.40), La/Ce (average 1.45), Lan/Ndn (average 2.16), Dyn/Ybn (average 0.33), and light REE/heavy REE (average 8.40; LREE > HREE), as well as Ba (average 920 ppm) and total REE contents (average 6.96 ppm) negative Ce and positive Eu anomalies, Dehoo could be considered a predominantly submarine hydrothermal Mn deposit complemented by terrigenous detrital mafic material.  相似文献   
59.
Temporal changes of meteorological variables can affect reference evapotranspiration (ET0). The goal of the present research is to analyze the changes of ET0 and identify the impact of effective meteorological parameters to the changes of ET0. For this purpose, daily meteorological data recorded in 30 synoptic stations of Iran during 1960–2014 were used. The annual and seasonal values of ET0 were calculated by the recorded data. To calculate ET0, FAO56 Penman–Monteith method (standard method) was used. The annual and seasonal trends of ET0 and its eight effective parameters were analyzed. Then the contributions of effective parameters changes on ET0 were determined. To analyze ET0 trend at annual and seasonal scales, two common methods, Spearman’s Rho and Mann–Kendall tests, were used. The R 2 = 0.99 showed that the results of the mentioned methods were similar and on the basis of T-statistic <0.057, their difference was not significant (95% confidence level). Therefore, only one method’s results (Spearman’s Rho) were reported. On the basis of Spearman’s Rho results, the annual and seasonal values of ET0 had negative trend in most of arid and semi-arid stations while the trend of this parameter was positive in humid and very humid stations. At annual and seasonal scales, decreasing in wind speed (W), temperature (T), sunshine hours (n), minimum temperature (TN), dew point temperature (TD), maximum temperature (TX), saturation vapor pressure deficit (SVPD) and solar radiation (RS) was observed in 58, 54, 39, 43, 56, 65, 65 and 37% studied stations, respectively. In many scales, the results showed that TX and W were the most effective meteorological variables on ET0 changes and then SVPD was located in second step in arid and semi-arid stations. In humid and very humid stations, W was the first effective parameter at all scales, except autumn.  相似文献   
60.
Before starting seismic cycle of Ahar–Varzaghan 2012 event, a partial gap in the form of a pre-seismic calm sequence (seismicity rate, r = 0.46 event/year, b = 1.4) with duration of 303 days spatially has dominated over the entire seismogenic area. From April 17, 2012, to May 31, 2012, r significantly increased to 2.16, indicating strong foreshock sequence, and b value changed to 1.9, remarkably. In the last two months before the mainshock, foreshocks have partially migrated toward the earthquake fault (with a decrease in size, b = 2.0). Significantly, high rate of seismicity and low V P /V S (1.64) in the foreshocks sequence and also very high seismicity rate (17.3) and high V P /V S (1.76) in the aftershocks sequence make substantial differences between the seismic cycle and the background seismicity. Moreover, a significant E–W migration of the microseismicity was confirmed in the study area.  相似文献   
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