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1.
Dorostkar  Ehsan  Najarsadeghi  Mahsa 《GeoJournal》2022,87(4):885-895

The shift to building capacity and the loss of regional equilibrium may undermine service delivery and create a hardness issue for governmental and non-governmental organizations. Different countries follow different frameworks for regional equilibrium to evaluate the results of their actions. To achieve good regional equilibrium, we have performed a comparative analysis between the 10 existing frameworks and put 5 main criteria along with 60 sub-criteria in a checklist. We examined the method of measuring these components with the help of various indicators and to distribute weight between these indicators, we consulted experts. Finally, Iran is discussed with examples of direct indicators that may be used to measure the sub-criteria of each specific criterion. The quantification process is also shown by several specific representative indicators. For example, Mobile phones to the population, general practitioners per population, health and social employees to the population. Researchers, policy-makers, decision-makers, and decision takers, are those who can use the method studied in this study to assess the level of regional equilibrium in their country specifically and according to the environmental conditions and the current situation in the region.

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2.
Although the Volterra models are non-parsimonious ones, they are being used because they can mimic dynamics of complex systems. However, applying and identification of the Volterra models using data may result in overfitting problem and uncertainty. In this investigation we evaluate capability of different wavelet forms for decomposing and compressing the Volterra kernels in order to overcome this problem by reducing the number of the model coefficients to be estimated and generating smooth kernels. A simulation study on a rainfall?runoff process over the Cache River watershed showed that the method performance is successful due to multi-resolution capacity of the wavelet analysis and high capability of the Volterra model. The results also revealed that db2 and sym2 wavelets have the same high potential in improving the linear Volterra model performance. However, QS wavelet was more successful in yielding smooth kernels. Moreover, the probability of overfitting while identifying the nonlinear Volterra model may be less than the linear model.  相似文献   
3.
Stochastic Environmental Research and Risk Assessment - Organizations are continuously endeavoring to provide a healthy work environment without any incident, by Health, Safety, and Environment...  相似文献   
4.
We investigate the mean velocity dispersion and the velocity dispersion profile of stellar systems in modified Newtonian dynamics (MOND), using the N -body code n-mody , which is a particle-mesh-based code with a numerical MOND potential solver developed by Ciotti, Londrillo & Nipoti. We have calculated mean velocity dispersions for stellar systems following Plummer density distributions with masses in the range of 104 to  109 M  and which are either isolated or immersed in an external field. Our integrations reproduce previous analytic estimates for stellar velocities in systems in the deep MOND regime  ( a i, a e≪ a 0)  , where the motion of stars is either dominated by internal accelerations  ( a i≫ a e)  or constant external accelerations  ( a e≫ a i)  . In addition, we derive for the first time analytic formulae for the line-of-sight velocity dispersion in the intermediate regime  ( a i∼ a e∼ a 0)  . This allows for a much-improved comparison of MOND with observed velocity dispersions of stellar systems. We finally derive the velocity dispersion of the globular cluster Pal 14 as one of the outer Milky Way halo globular clusters that have recently been proposed as a differentiator between Newtonian and MONDian dynamics.  相似文献   
5.
Abstract

By application of the limit equilibrium method associated with Coulomb failure mechanism, the effect of variation of undrained shear strength with depth on seismic bearing capacity was evaluated. The approach followed in this study to take into account seismic forces is pseudo-static. It is also assumed that the occurrence of an earthquake does not have any effects on the values of soil cohesion. Two different marine soil deposits exhibiting linear and bilinear variations of undrained shear strength with depth were considered. The undrained bearing capacity factor has been computed as a function of dimensionless parameters of λ1B/c0, λ2B/c0, and Zt/B. The results of this paper have been compared with solutions reported in the literature, and the consistency of the results confirmed the ability of Coulomb failure mechanism and its corresponding limit equilibrium method formulation in static condition. Furthermore, the pseudo-static bearing capacity of shallow foundations on heterogeneous marine deposit is addressed. Finally the results of this study presented in the form of table and design charts.  相似文献   
6.
In this study, we investigated the possible effects of paraquat and micro-plastics on blood biochemical parameters in common carp (Cyprinus carpio). We exposed C. carpio for 21 days to sublethal concentrations of paraquat (0.2 and 0.4 mg L?1) and micro-plastics (1 and 2 mg L?1), alone or in combination. Blood biochemical analysis indicated that exposure to 0.4 mg L?1 paraquat and mixture of paraquat and micro-plastics was followed by an increase in aspartate aminotransferase (AST), alkaline phosphatase (ALP), and creatine phosphokinase (CPK) activities and glucose levels. The activity of ALP and CPK showed a significant increase in fish treated with 2 mg L?1 micro-plastics. No significant changes were observed in glucose level, AST, ALT, and LDH activities in fish exposed to micro-plastics. Exposure to paraquat and/or micro-plastics resulted in a significant decrease in total protein, globulin, cholesterol, and triglyceride levels and γ-glutamyl transferase activity. When fish were exposed to paraquat or paraquat and micro-plastics, alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) activities increased significantly compared to the control group. Treating fishes with a mixture of paraquat and 2 mg L?1 micro-plastics caused a significant increase in albumin levels. However, a significant decrease in the albumin level was observed after exposure to paraquat or micro-plastics. Creatinine levels increased after exposure to paraquat and/or micro-plastics. The results indicate that increased doses of micro-plastics in water significantly increased toxic effects of paraquat in fish. Finally, these data support the hypothesis that changes in blood biochemical parameters were induced by exposure to paraquat and/or micro-plastics.  相似文献   
7.
In this paper, an upper bound estimate of the limit load on non-associative coaxial granular materials is presented. The kinematic approach of the upper bound limit analysis has been utilised. The failure mechanism is assumed to coincide with the direction of the shear bands at every point throughout the body. The shear band orientation in non-associative coaxial materials, i.e. those with the same major principal stress and major principal strain increment directions, can be found based on the angle of dilation and the major principal stress direction. Therefore, having known the stress field at limiting equilibrium, the orientation of the shear bands and hence, the failure mechanism can be obtained. In this study, the stress field is first determined by the method of stress characteristics. Then, the finite element interpolation technique is used to interpolate the stress field and to find the orientation of the shear bands at every point within the field. Once the failure mechanism and the stress state at every point along velocity discontinuities have been found, the upper bound limit analysis has been performed to estimate the limit load.  相似文献   
8.
9.
This study evaluates the performances of two distinct linear and non-linear models for simulating non-linear rainfall–runoff processes and their applications to flood forecasting in the Navrood River basin, Iran. Due to the excellent capacity of the artificial neural networks [multilayer perceptron (MLP)] and Volterra model, these models were used to approximate arbitrary non-linear rainfall–runoff processes. The MLP model was trained using two different training algorithms. The Volterra model was applied as a linear model [the first-order Volterra (FOV) model] and solved using the traditional ordinary least-square (OLS) method. Storm events within the Navrood River basin were used to verify the suitability of the two models. The models’ performances were evaluated and compared using five performance criteria namely coefficient of efficiency, root mean square error, error of total volume, relative error of peak discharge, and error of time for peak to arrive. Results indicated that the non-linear MLP models outperform the linear FOV model. The latter was ineffective because of the non-linearity of the rainfall–runoff process. Moreover, the OLS method is inefficient when the FOV model has many parameters that must be estimated.  相似文献   
10.
Mapping surveys of coastal benthic habitat in Qeshm Island Geopark, Persian Gulf, were conducted using a combination of biological, sedimentological and echo‐sounding data. The survey area covered approximately 233 km2 in a depth range of 5–25 m, and the data were acquired from a single beam echo sounder, grab, video and still photography. Sediment and macrofauna samples were collected by grab at 76 stations and subjected to classification and ordination analyses. Two acoustic classes were identified differentiating along the near/offshore axis. Sediment texture was dominated by fine grain sizes, with five distinct sub‐sediment types. In total, 214 macrobenthic taxa were identified, of which polychaetes accounted for 60%. Other dominant groups included young sponges, nematodes, malacostracan crustacean, bivalves, ostracods and ophiuroids. Underwater videos and still photos integrated the macrofaunal and sedimentary data and revealed a range of biogenic sedimentary features such as burrows and tubes. The biological data identified six main biological assemblages showing an inshore/offshore pattern. The macrobenthic abundance did not demonstrate a significant difference with depth, although polychaetes were positively correlated with depth. The highest abundance and species richness were observed at median depths. Species distribution and diversity did not show any correlation with sediment type. A preliminary habitat mapping of the south coast of the Qeshm Island Geopark has been carried out, integrating acoustic, sediment and biological data.  相似文献   
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