Constraints on unconsolidated pyroclastic flow sediments related REE enrichments originated from potassic-alkaline Gölcük stratovolcano: Darıdere-Direkli-Yakaören (DDY) table 4deposits,southwestern Anatolia of Turkey     

Budakoglu  Murat  Unluer  Ali Tugcan  Doner  Zeynep  Kocaturk  Huseyin  Kaya  Mustafa  Kumral  Mustafa  Kirikoglu  M. Sezai 《中国地球化学学报》2021,40(6):926-944

Acta Geochimica - In the last five decades, Rare Earth Elements (REE) are mostly produced from carbonatite complexes and alkaline magmatic environments. In this respect, pyroclastic flows produced...  相似文献   

An empirical relation for parameter mi in the Hoek–Brown criterion of anisotropic intact rocks with consideration of the minor principal stress and stress-to-weak-plane angle     

Wen  Tao  Tang  Huiming  Huang  Lei  Hamza  Asif  Wang  Yankun 《Acta Geotechnica》2021,16(2):551-567

Acta Geotechnica - The parameter mi accounts for the anisotropy of rock strength, and the accurate determination of mi is a primary requirement of the Hoek–Brown (H–B) strength...  相似文献   

Pore-water pressure development in a frozen saline clay under isotropic loading and undrained shearing     

Lyu  Chuangxin  Nishimura  Satoshi  Amiri  Seyed Ali Ghoreishian  Zhu  Feng  Eiksund  Gudmund Reidar  Grimstad  Gustav 《Acta Geotechnica》2021,16(12):3831-3847

Acta Geotechnica - A systematical testing program on frozen Onsøy clay under isotropic loading and undrained shearing at different temperatures...  相似文献   

An effective stress-based DSC model for predicting the coefficient of lateral soil pressure in unsaturated soils     

Akbari Garakani  Amir  Pirjalili  Ali  Desai  Chandrakant S. 《Acta Geotechnica》2021,16(12):3813-3830

Acta Geotechnica - In this study, an analytical model is developed to establish a framework for predicting the coefficient of lateral soil pressure in unsaturated soils. To this end, the disturbed...  相似文献   

Late quaternary seismic stratigraphy and active faults of the Gulf of İzmit (NE Marmara Sea)     

Mahmut Okyar  Ali Pinar  Devrim Tezcan  Züheyr Kamaci 《Marine Geophysical Researches》2008,29(2):89-107

The Upper Quaternary seismic stratigraphy and active faults of the Gulf of İzmit were investigated by means of high-resolution shallow seismic profiling data in the source region of 1999 İzmit earthquake. High-resolution seismic reflection data correlated with borehole data indicate that the stratigraphy of İzmit Bay consists of three distinct depositional sequences formed in response to middle Pleistocene-Holocene sea-level changes. Reflector R, separating the pre-Holocene sequences (1 and 2) from the Holocene sequence (3), represents an erosional unconformity produced by the subaerial fluvial erosion of the continental shelves at the time of the last glacial maximum. Occasional, anomalous reflections (acoustic turbidity) observed within the Holocene sequence are interpreted as gas accumulations. The maximum thickness of the Holocene sediments is found to be about 25 m. The isopach map of Holocene sediment implies that the thickness of the Holocene decreases from the east towards the central and western basins of İzmit Bay. Two distinct fault systems are interpreted in İzmit Bay. The main fault system extending roughly in an E-W direction along the Gulf of İzmit is an active right lateral strike slip fault with a normal component. The secondary faults are normal faults striking in different directions and these are identified as being both active and inactive. In addition, prominent compressive features are identified in the seismic cross-sections of some profiles acquired to the east of Hersek Peninsula where the focal mechanisms of the aftershocks of the 1999 İzmit earthquake also reveal predominantly reverse faulting mechanisms, as identified by a local dense seismic network.  相似文献   

Using uncertainty and sensitivity analysis for finding the best rainfall-runoff model in mountainous watersheds(Case study: the Navrood watershed in Iran)     

Arash ADIB  Morteza LOTFIRAD  Ali HAGHIGHI 《山地科学学报》2019,(3)

In watersheds that have not sufficient meteorological and hydrometric data for simulating rainfall-runoff events, using geomorphologic and geomorphoclimatic characteristics of watershed is a conventional method for the simulation. A number of rainfall-runoff models utilize these characteristics such as Nash-IUH, Clark-IUH, Geomorphologic Instantaneous Unit Hydrograph(GIUH), Geomorphoclimatic Instantaneous Unit Hydrograph(GcIUH), GIUH-based Nash(GIUH-Nash) and GcIUH-based Clark(GcIUH-Clark). But all these models are not appropriate for mountainous watersheds. Therefore, the objective of this study is to select the best of them for the simulation. The procedure of this study is: a) selecting appropriate rainfall-runoff events for calibration and validation of six hybrid models, b) distinguishing the best model based on different performance criteria(Percentage Error in Volume(PEV); Percentage Error in Peak(PEP); Percentage Error in Time to Peak(PETP); Root Mean Square Error(RMSE) and Nash-Sutcliffe model efficiency coefficient(ENS)), c) Sensitivity analysis for determination of the most effective parameter at each model, d) Uncertainty determination of different parameters in each model and confirmation of the obtained results by application of the performance criteria. For application of this procedure, the Navrood watershed in the north of Iran as a mountainous watershed has been considered. The results showed that the ClarkIUH and GcIUH-Clark are suitable models for simulation of flood hydrographs, while other models cannot simulate flood hydrographs appropriately. The sensitivity analysis shows that the most sensitive parameters are the infiltration constant rate and time of concentration in the Clark-IUH model. Also, the most sensitive parameters include the infiltration constant rate and storage coefficient in the GcIUHClark model. The Clark-IUH and GcIUH-Clark models are more sensitive to their parameters. The Latin Hypercube Sampling(LHS) on Monte Carlo(MC) simulation method was used for evaluation of uncertainty of data in rainfall-runoff models. In this method 500 sets of data values are produced and then the peak discharge of flood hydrographs for each produced data set is simulated with rainfall-runoff models. The uncertainty of data changes the value of simulated peak discharge of flood hydrograph. The uncertainty analysis shows that the observed peak discharges of different rainfall-runoff events are within the range of values of simulated by the six hybrid rainfall-runoff models and IUH that inputs of these models were the produced data sets. The range of the produced peak discharge of flood hydrographs by the Clark-IUH and GcIUH-Clark models is wider than those of other models.  相似文献   

Spatial analysis of water quality and its suitability in farming giant freshwater prawn (Macrobrachium rosenbergii) in Negeri Sembilan region,Peninsular Malaysia     

Benjamin Ezekiel Bwadi  Firuza Begham Mustafa  Mohammad Lokman Ali  Subha Bhassu 《Singapore journal of tropical geography》2019,40(1):71-91

Finding potential sites for resilient prawn production in the tropical environment that also prevents wastage of natural resources is not an easy task. The purpose of this study is to evaluate water quality suitability for prawn farming in Negeri Sembilan of Peninsular Malaysia based on Geographic Information System (GIS). To achieve this goal, numerous criteria including sources of water, water temperature, water pH, sources of pollution, salinity, soil texture and availability of phytoplankton criteria were considered for the modelling process. Analytic Hierarchy Process (AHP) technique was performed to standardize the criteria and the weighting process. The weighted overlay of indicators and results were accomplished by applying the Multi‐Criteria Decision Analysis (MCDA) method in GIS. It was indicated that the Negeri Sembilan area has potential for prawn farming. The results showed that about 25 per cent (163 056.93 ha) of the area was most suitable for prawn farming, about 58 per cent (384 656.88 ha) was considered moderately suitable, while 18 per cent (117 633.49 ha) was regarded as least suitable. The study concluded that the multi‐criteria decision analysis of water quality for prawn farming is vital for regional economic planning in the Negeri Sembilan area and also significant when establishing a model for aquaculture development.  相似文献   

Use of genetic algorithm in new approach to modeling of flood routing     

El Alaoui El Fels  Abdelhafid  Alaa  Noureddine  Bachnou  Ali 《中国海洋湖沼学报》2019,37(1):72-78

Journal of Oceanology and Limnology - The hydrological models and simplified methods of Saint-venant equations are used extensively in hydrological modeling, in particular for the simulation of the...  相似文献   

Experimental Evaluation of A New Developed Algorithm for An Autonomous Surface Vehicle and Comparison with Simulink Results     

Mousazadeh  Hossein  Kiapey  Ali 《中国海洋工程》2019,33(3):268-278

China Ocean Engineering - Performing repeatable duties automatically was the dreams of human being for centuries. Although full autonomy has long been dreamed of by visionaries, many researches...  相似文献   

Estimation of crowd density from UAVs images based on corner detection procedures and clustering analysis     

Ali Almagbile 《地球空间信息科学学报》2019,22(1):23-34

With rapid developments in platforms and sensors technology in terms of digital cameras and video recordings, crowd monitoring has taken a considerable attentions in many disciplines such as psychology, sociology, engineering, and computer vision. This is due to the fact that, monitoring of the crowd is necessary to enhance safety and controllable movements to minimize the risk particularly in highly crowded incidents (e.g. sports). One of the platforms that have been extensively employed in crowd monitoring is unmanned aerial vehicles (UAVs), because UAVs have the capability to acquiring fast, low costs, high-resolution and real-time images over crowd areas. In addition, geo-referenced images can also be provided through integration of on-board positioning sensors (e.g. GPS/IMU) with vision sensors (digital cameras and laser scanner). In this paper, a new testing procedure based on feature from accelerated segment test (FAST) algorithms is introduced to detect the crowd features from UAV images taken from different camera orientations and positions. The proposed test started with converting a circle of 16 pixels surrounding the center pixel into a vector and sorting it in ascending/descending order. A single pixel which takes the ranking number 9 (for FAST-9) or 12 (for FAST-12) was then compared with the center pixel. Accuracy assessment in terms of completeness and correctness was used to assess the performance of the new testing procedure before and after filtering the crowd features. The results show that the proposed algorithms are able to extract crowd features from different UAV images. Overall, the values of Completeness range from 55 to 70 % whereas the range of correctness values was 91 to 94 %.  相似文献