In this article, generalized differential quadrature method (GDQM) is used to study the free vibrational behavior of variable cross section nano beams. Eringen's nonlocal elastic theory is taken into account to model the small scale effects and nonuniformity is assumed by exponentially varying the width of nano beam. Governing equation of motion is solved using generalized differential quadrature method with different numbers of sampling points. Effects of increasing the sampling points in reaching more accurate results for first three frequency parameters are presented and it is shown that after a specific number of sampling points, results merge to a certain accurate number. It is concluded that generalized differential quadrature method is able to reach the correct answers comparing to analytical results. Moreover, due to the stiffness softening behavior of small-scale structures, necessity of using Eringen's nonlocal elastic theory to model the small scale effects due to the frequency variation is observed. |
Nanotransformations of a blanket at the fair dimensional combined processing with imposing of electric field the tool in the form of untied metal granules are considered. An object of researches are the figurine details applied in aviation, the missile and space equipment and in the oil and gas industry: driving wheels and a flowing part of cases of turbo-pump units, screws, krylchatka where there are sites of variable curvature with limited access of the tool in a processing zone.It is shown that the combination in the combined process of two-component technological environments of current carrying granules and the electroconductive liquid environment given with a high speed to a processing zone allows to receive the required quality of a blanket; action of electric field from a source with the increased tension allows to create at fair dimensional processingthe required peening from blows of firm granules. It gives the chance to raise a resource and durability of responsible knots of the aerospace equipment and oil and gas equipment, to expand the field of use of the combined processing with untied granules on a detailwith the sitesnot available to processing by a profile electrode.
This report deals synthesis of CuInGa (CIG) nano materials along with doctor blade and spin coated thin films selenization and their physical properties. The doctor blade and spin coated CIGS/SLG thin films thicknesses are obtained ̴ 2 μm and ̴ 2.95 μm. Raman spectroscopy of these thin films leads the chalcopyrite phase formation by exhibiting the peak at wave number 171 cm-1. The well developed grain growths of spin coated thin film are appeared in the surface morphology. While the grain growths developments in doctoral blade coated thin film is rather hard and fuzzy. EDS measurement recognised the existence of the compositional ratio presence of the alloying elements Cu, In. Ga and Se. The doctor blade and spin coated CIGS/SLG thin films are exhibited the UV- Visible transmission peak in the wave length range 240 nm 320 nm. The optical energy band gaps for the doctor blade and spin coated CIGS thin films are obtained 1.41eV and 1.5 eV.
The technology of vermicomposting containing their leachates, teas and other extracts such as vermiwash as a result of earthworm action is widely applied for safe management of agricultural, industrial, domestic and hospital wastes. Remediation of polluted soils, improving crop productivity and inducing the resistance against biotic and abiotic stresses are other advantages of vermicompost derived liquids when used in agriculture. Contrary to the fact that chemical fertilizers are still widely used in agriculture, societies gradually become aware of the negative effects of these fertilizers on their health. Therefore, vermicompost derived liquids contain high amount of valuable plant nutrients which has the potential to be used as liquid fertilizer. This paper reviews the potential of vermicompost derived liquids as as an efficient combination of nutrient source of vermicompost derived liquids contributing to plant growth and acting as a deterrent to biotic and abiotic stresses.
Fire is one of the most serious hazards, which causes many economic, social, ecological, and human damages every year in the world. Fire in forests and natural ecosystems destroys wood, regeneration, forest vegetation, as well as soil erosion and forest regeneration problems (due to the dryness of the weather and the weakness of the soil). Awareness of the extent of the zones that have been fired is important for forest management. On the other hand, the difficulty of fieldwork due to the high cost and inaccessible roads, etc. reveals the need for using remote sensing science to solve this problem. In this research, MODIS satellite images were used to detect and determine the fire extent of Golestan province forests in northern Iran. MID13q1 and MOD13q1 images were used to detect the normal conditions of the environment. The 15-year time series data were provided for the NDVI and NDMI indicators in 2000-2015. Then, the behavior of indicators in the fire zone was studied on the day after the fire. The burned zones by the fire were specified by determining the appropriate threshold and then, they were compared to long-term normals. In the NDMI and NDVI indicators, the mean of the numeric value threshold limit for determining the burnt pixels was respectively 1.865 and 0.743 of the reduction in their normal long-term period, which are selected as fire pixels. The results showed that the NDMI index could determine the extent of the burned zone with the accuracy of 95.15%.
Identify and diagnosis of homogenous units and separating them and eventually planning separately for each unit are considered the most principled way to manage units of forests and creating these trustable maps of forest’s types, plays important role in making optimum decisions for managing forest ecosystems in wide areas. Field method of circulation forest and Parcel explore to determine type of forest require to spend cost and much time. In recent years, providing these maps by using digital classification of remote sensing’s data has been noticed. The important tip to create these units is scale of map. To manage more accurate, it needs larger scale and more accurate maps. Purpose of this research is comparing observed classification of methods to recognize and determine type of forest by using data of Land Cover of Modis satellite with 1 kilometer resolution and on images of OLI sensor of LANDSAT satellite with 30 kilometers resolution by using vegetation indicators and also timely PCA and to create larger scale, better and more accurate resolution maps of homogenous units of forest. Eventually by using of verification, the best method was obtained to classify forest in Golestan province’s forest located on north-east of country.
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