the behavior of suspended sediment during flood events is not only a function of energy conditions, i.e. sediment is stored at low flow and transported under high flow conditions, but also is related to the variations in sediment supply and sediment depletion. these changes in sediment availability result in so-called hysteresis effects. therefore, hysteresis pattern analysis is of great import...

introduction climate change happens due to abnormal changes of climate within the earth’s atmosphere and their consequences. one of the most significant effects of climate change is the irreversible damage to some floral species and forest ecosystems. tree species reflect the impact of climate changes on their ring width. generally, tree rings vary in size each year depending upon the environme...

among the most common types of problematic soils, are probably the expansive ones. one of the modern methods of strengthening and improving the soil in place is the use of electro-osmotic improving treatment. this paper presents the design of an apparatus suitable for electro-osmotic treatment. a soil sample of a high expansive potential was compacted and the effect of electro-osmotic treatment...

a study was carried out to examine the effect of different levels of herbal methionine and dl-methionine on the growth performance and immunocompetence of broiler chickens fed on a corn-soybean meal diet. a total of 225 old male broiler chickens (ross 308) were used as experimental samples in a completely randomized design. they were randomly assigned to 9 treatments each of 5 replicates in eve...

application of various composts has been intensified in agriculture, due to manifestation of negative effects of chemical fertilizers on environment and soil fertility. however, their usage should be accompanied by environmental and nutritional studies. to study the effects of sulfur granular compost on yield and yield components of two wheat cultivars, a pot experiment was conducted in a compl...

most geologic changes have a seismic response but sometimes this is expressed only in certain spectral ranges hidden within the broadband data. spectral decomposition is one of the methods which can be utilized to help interpreting such cases. there are several time-frequency methods including: short-time fourier transform (stft), continuous wavelet transform (cwt), wigner-ville distribution (w...

this research was conducted to study the effects of styrene and methyl methacrylate cell lumen monomers on the mechanical properties and decay resistance of beech wood. mechanical and decay resistance test samples were prepared according to astm d143-94 and din en113 standards and impregnated with five concentration monomer solution 0, 40, 60, 80 and 100 percent using bethell method. treated sa...

a synoptic method based on stream analysis is applied to understand the governing mechanism of summer rainfall occurrence in the south of iran. based on this, the rainfall data of 152 stations of iran were analyzed for a 33-year period (1970-2002). investigating the spatial and temporal distribution of summer rainfall, a typical rainy region is recognized in the south east of iran. it is found ...

For a scalar delay differential equation ẋ(t)+ a(t)x(h(t))− b(t)x(g(t))= 0, a(t) 0, b(t) 0, h(t) t, g(t) t, a connection between the following properties is established: nonoscillation of the differential equation and the corresponding differential inequalities, positiveness of the fundamental function and existence of a nonnegative solution for a certain explicitly constructed nonlinear integr...