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11.
Iman Malekmohamadi Mohammad Reza Bazargan-Lari Reza Kerachian Mohammad Reza Nikoo Mahsa Fallahnia 《Ocean Engineering》2011,38(2-3):487-497
Wave Height (WH) is one of the most important factors in design and operation of maritime projects. Different methods such as semi-empirical, numerical and soft computing-based approaches have been developed for WH forecasting. The soft computing-based methods have the ability to approximate nonlinear wind–wave and wave–wave interactions without a prior knowledge about them. In the present study, several soft computing-based models, namely Support Vector Machines (SVMs), Bayesian Networks (BNs), Artificial Neural Networks (ANNs) and Adaptive Neuro-Fuzzy Inference System (ANFIS) are used for mapping wind data to wave height. The data set used for training and testing the simulation models comprises the WH and wind data gathered by National Data Buoy Center (NDBC) in Lake Superior, USA. Several statistical indices are used to evaluate the efficacy of the aforementioned methods. The results show that the ANN, ANFIS and SVM can provide acceptable predictions for wave heights, while the BNs results are unreliable. 相似文献
12.
Hormozgan Province with arid climate is an important source of energy resources for Iran. This study investigates the results of hydrogeochemical investigation and its tectonic control in Hormozgan Province, Southern Iran. The chemical analysis of 158 groundwater samples was evaluated to determine the hydrogeochemical processes and ion concentration background in the region. Several NW-SE trending and NE-dipping basement reverse faults have intersected the area and have divided it into four tectonic terranes. Huge extension of Hormuz Formation in Zagros Foredeep tectonic terrane has increased the cations, Cl and SO4 concentration in groundwaters. HCO3 concentration in Sanandaj-Sirjan Zone and High Zagros is the result of silicate weathering or carbonates. Eighty-three percent of samples have negative CAI values in High Zagros, Sanandaj-Sirjan Zone, and eastern Zagros Fold Thrust Belt. The dominant hydrochemical facies of groundwater are Na-Mg-Ca-Cl (25.3% of samples) and Na-Mg-Cl (20.9% of samples). They are confined to the west of Main Zagros Reverse Fault and east of High Zagros Fault, respectively. The salt content of the groundwater indicates samples with very high salinity—as a result of Hormuz Formation—are mainly limited to the west of High Zagros Fault while samples with high to medium salinity are mainly limited to the east of this fault. Eastward increment of rock weathering is controlled with thrust faults activity of the area and southwestward migration of deformation front. Westward increment of evaporites is compatible with Hormuz Formation/salt dome density through the area. 相似文献
13.
Recently much research has been focused on developing techniques and systems for providing routes within buildings. While outdoor routing is based on criteria such as shortest, fastest and least turns, indoor routing is primarily based on accessibility and safety criteria, and while outdoor routing could adversely be impacted by weather and traffic, among other conditions, such conditions do not affect indoor routing. However, developing techniques that meet user's indoor routing preferences, especially those with special needs, is a challenging task. An example is development of a set of techniques that avoids a hallway with a protruding object to allow safe passage by the visually impaired or that avoids stairs for the mobility impaired. In this article, we present and analyze new techniques based on the Americans with Disabilities Act (ADA) standards that provide routes within buildings and meet user's special needs and preferences. 相似文献
14.
Seismic ambient noise of surface wave tomography was applied to estimate Rayleigh wave empirical Green's functions(EGFs) and then to study crust and uppermost mantle structure beneath the Makran region in south-east Iran.12 months of continuous data from January 2009 through January 2010,recorded at broadband seismic stations,were analyzed.Group velocities of the fundamental mode Rayleigh wave dispersion curves were obtained from the empirical Green's functions.Multiplefilter analysis was used to plot group velocity variations at periods from 10 to 50 s.Using group velocity dispersion curves,1-D vs velocity models were calculated between several station pairs.The final results demonstrate significant agreement to known geological and tectonic features.Our tomography maps display low-velocity anomaly with SW-NE trend,comparable with volcanic arc settings of the Makran region which may be attributable to the geometry of Arabian Plate subducting beneath the overriding the Lut block.The northward subducting Arabian Plate is determined by high-velocity anomaly along the Straits of Hormuz.At short periods(20 s),there is a sharp transition boundary between low- and high-velocity transition zone with the NW trending at the western edge of Makran which is attributable to the Minab fault system. 相似文献
15.
Evaluation of efficiency of different estimation methods for missing climatological data 总被引：2，自引：1，他引：1
Mahsa Hasanpour Kashani Yagob Dinpashoh 《Stochastic Environmental Research and Risk Assessment (SERRA)》2012,26(1):59-71
Reliable estimation of missing data is an important task for meteorologists, hydrologists and environment protection workers
all over the world. In recent years, artificial intelligence techniques have gained enormous interest of many researchers
in estimating of missing values. In the current study, we evaluated 11 artificial intelligence and classical techniques to
determine the most suitable model for estimating of climatological data in three different climate conditions of Iran. In
this case, 5 years (2001–2005) of observed data at target and neighborhood stations were used to estimate missing data of
monthly minimum temperature, maximum temperature, mean air temperature, relative humidity, wind speed and precipitation variables.
The comparison includes both visual and parametric approaches using such statistic as mean absolute errors, coefficient of
efficiency and skill score. In general, it was found that although the artificial intelligence techniques are more complex
and time-consuming models in identifying their best structures for optimum estimation, but they outperform the classical methods
in estimating missing data in three distinct climate conditions. Moreover, the in-filling done by artificial neural network
rivals that by genetic programming and sometimes becomes more satisfactory, especially for precipitation data. The results
also indicated that multiple regression analysis method is the suitable method among the classical methods. The results of
this research proved the high importance of choosing the best and most precise method in estimating different climatological
data in Iran and other arid and semi-arid regions. 相似文献