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Time–space fractional governing equations of transient groundwater flow in confined aquifers: Numerical investigation 
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下载免费PDF全文 In order to model non‐Fickian transport behaviour in groundwater aquifers, various forms of the time–space fractional advection–dispersion equation have been developed and used by several researchers in the last decade. The solute transport in groundwater aquifers in fractional time–space takes place by means of an underlying groundwater flow field. However, the governing equations for such groundwater flow in fractional time–space are yet to be developed in a comprehensive framework. In this study, a finite difference numerical scheme based on Caputo fractional derivative is proposed to investigate the properties of a newly developed time–space fractional governing equations of transient groundwater flow in confined aquifers in terms of the time–space fractional mass conservation equation and the time–space fractional water flux equation. Here, we apply these time–space fractional governing equations numerically to transient groundwater flow in a confined aquifer for different boundary conditions to explore their behaviour in modelling groundwater flow in fractional time–space. The numerical results demonstrate that the proposed time–space fractional governing equation for groundwater flow in confined aquifers may provide a new perspective on modelling groundwater flow and on interpreting the dynamics of groundwater level fluctuations. Additionally, the numerical results may imply that the newly derived fractional groundwater governing equation may help explain the observed heavy‐tailed solute transport behaviour in groundwater flow by incorporating nonlocal or long‐range dependence of the underlying groundwater flow field. 相似文献
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Education infrastructure issues have been one of the most important topics in developing countries that have difficulty reserving money for education infrastructure needs, especially Turkey. Development plans have a crucial role in meeting school infrastructure needs in Turkey. Generally, the expropriation method has been used for land transitions from private to public ownership. However, scarcity of monetary resources for such land transitions and legal/technical deficiencies delays the process. The main objectives of this paper are to respond to the need of the education sector by using land management tools and to identify the most suitable land management tool for allocating basic and primary school lands free of charge. Current trends, education indicators, management responsibility and financial resources, statistical and economical information, education infrastructure needs, and qualitative-quantitative characteristics of the pupils in the Turkish education system are analyzed based on national and international reports. Then, the property right problems experienced in the process of allocating school lands are defined. Methods of transferring school lands to public ownership are examined, and the benefit-cost relationships are revealed. Land readjustment (LR) would make an important contribution to planning decisions and the implementation stage in the sustainable management of school lands. 相似文献
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In this review, the shifts in organic matter (OM) accumulation and C:N ratios in lake sediments to reconstruct paleoclimate and paleo-environmental changes since the early Holocene period are presented. The C:N proxy data of total OM reflect wet climatic conditions during early Holocene (10 to 8.2 kyrs BP) due to enhanced southwest monsoon. This was followed by intermittent arid conditions during the mid and late Holocene period (8.2 to 2.8 kyr BP). Enhanced values of C:N ratio during middle to late Holocene (7.8–2.3 kyrs B.P) indicate periods with lower lake levels and minimum precipitation, while decreased C:N ratio point to stronger SW monsoon and expansion of the lakes. Further, C:N and δ13C results from the lake sediments reveal a detailed and continuous paleo-environmental changes in the relative sources of OM (allochthonous vs autochthonous). Proxy records using such natural archives have also been utilized to reconstruct past extreme events and environmental changes around the lake systems, such as causes for lake desiccation, hydrographic changes, alternations between C3 and C4 vegetation and historical disturbances in the catchment area since the early-late Holocene period coupled with the Indian summer monsoon. 相似文献
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Abdulkadir Yasar Erdo?an Simsek Mehmet Bilgili Ahmet Yucel Ilhami Ilhan 《Meteorology and Atmospheric Physics》2012,115(1-2):81-87
The aim of this study is to estimate the monthly mean relative humidity (MRH) values in the Aegean Region of Turkey with the help of the topographical and meteorological parameters based on artificial neural network (ANN) approach. The monthly MRH values were calculated from the measurement in the meteorological observing stations established in Izmir, Mugla, Aydin, Denizli, Usak, Manisa, Kutahya and Afyonkarahisar provinces between 2000 and 2006. Latitude, longitude, altitude, precipitation and months of the year were used in the input layer of the ANN network, while the MRH was used in output layer of the network. The ANN model was developed using MATLAB software, and then actual values were compared with those obtained by ANN and multi-linear regression methods. It seemed that the obtained values were in the acceptable error limits. It is concluded that the determination of relative humidity values is possible at any target point of the region where the measurement cannot be performed. 相似文献
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Sarita?Gajbhiye?MeshramEmail author Randhir?Gautam Ercan?Kahya 《Theoretical and Applied Climatology》2018,132(3-4):939-951
The primary focus of this study is the analysis of droughts in the Tons River Basin during the period 1969–2008. Precipitation data observed at four gauging stations are used to identify drought over the study area. The event of drought is derived from the standardized precipitation index (SPI) on a 3-month scale. Our results indicated that severe drought occurred in the Allahabad, Rewa, and Satna stations in the years 1973 and 1979. The droughts in this region had occurred mainly due to erratic behavior in monsoons, especially due to long breaks between monsoons. During the drought years, the deficiency of the annual rainfall in the analysis of annual rainfall departure had varied from ?26% in 1976 to ?60% in 1973 at Allahabad station in the basin. The maximum deficiency of annual and seasonal rainfall recorded in the basin is 60%. The maximum seasonal rainfall departure observed in the basin is in the order of ?60% at Allahabad station in 1973, while maximum annual rainfall departure had been recorded as ?60% during 1979 at the Satna station. Extreme dry events (z score <?2) were detected during July, August, and September. Moreover, severe dry events were observed in August, September, and October. The drought conditions in the Tons River Basin are dominantly driven by total rainfall throughout the period between June and November. 相似文献
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Ahmet Güllü Ercan Yüksel Cem Yalçın A. Anıl Dindar Hasan Özkaynak Oral Büyüköztürk 《地震工程与结构动力学》2019,48(1):27-45
Input energy is the principal component of the energy balance equation. It is beneficial to determine, through its components, how the recoverable and irrecoverable energies are distributed within the structural elements. Several equations and attenuation relations to define mass-normalized input energy spectra exist in the literature. They are mainly proposed for elastic systems subjected to far-fault EQs. There is a lack of experimental verification of these proposed spectra. In this paper, experimental assessment was performed to the existing spectra, and further improvements were accomplished. For this purpose, steel cantilever columns were tested on the shake table for two specific historical EQs coincidently having similar spectral acceleration values. Based on the experimental results, a three-part mass-normalized relative input energy spectrum was formulated including soil type, EQ (corner period, intensity, duration, spectral acceleration, and velocity), and structural behavioral characteristics (period and structural damping). The proposed input energy spectrum was experimentally calibrated and numerically validated for various EQs featuring near- and far-field types. Analytical and experimental comparisons were made between the previously developed spectrum and the newly proposed one. The validation studies and the statistical evaluations exposed that the proposed spectrum yielded better agreement with the experimental and numerical results. 相似文献
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zcan Gyrgy Less Mria Bldi-Beke Katalin Kollnyi Ferhat Acar 《Journal of Asian Earth Sciences》2009,34(6):740-760
The marine Oligo-Miocene units of western Taurides, deposited under different tectonic regimes (in Bey Da?lar? platform in foreland and coeval sequences in hinterland), were studied to establish a high-resolution biostratigraphic framework. Biometric study of the full spectrum of larger foraminifera in a regional scale allowed us correlating them with the shallow benthic zonation (SBZ) system introduced by [Cahuzac, B., Poignant, A., 1997. Essai de biozonation de l’Oligo-Miocène dans les bassins européens à l’aide des grands foraminifères néritiques. Bulletin de la Société géologique de France 168, 155–169], and to determine the ages of these sites on zonal precision for the first time. In correlating these assemblages to standard shallow benthic zones, planktonic data were also used whenever possible. Taxa, classified under the genera Nummulites, Miogypsina, Miolepidocyclina, Nephrolepidina, Eulepidina, Heterostegina, Operculina and Cycloclypeus (?) and their assemblages, closely resemble to the fauna described from European basins. These groups characterize the SBZ 22B to 25 zones referring to a time interval from early Chattian to Burdigalian. However, a main gap in late Chattian (SBZ 23) and in early part of the Aquitanian (SBZ 24) is also recorded in the platform succession. In the meantime, rare Eulepidina in the Burdigalian levels suggest a clear Indo-Pacific influence. Based on the discovery of early Chattian (SBZ 22B) deposits (previously mapped under Eocene/Miocene units), the Oligo-Miocene stratigraphy of the Bey Da?lar? platform is also revised. A more precise chronology for regional Miocene transgression is presented based on the miogypsinid evolutionary scale. 相似文献