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Fuladipanah M.,Islamic Azad University at Ramhormoz | Jafarinia R.,Islamic Azad University of Arak
Ecology, Environment and Conservation | Year: 2014

River flow management requires discharge estimation. Unit hydrograph is an efficient method to flood hydrograph simulation. There are several models to create unit hydrograph. Clark model is one of the most widely used methods to produce unit hydrograph with its efficiency depending on the accuracy of estimation of storage coefficient and concentration time. In this the assessment of simulated unit hydrograph using Clark model has been investigated in Poledoab catchment, Iran. ARCGIS was used to evaluate physical properties of catchment in order to plot isochrones curves and time-area histogram. These curves were used to calculate storage coefficient and concentration time of catchment. The results showed that the Clark model has accepted simulation of peak time and peak discharge. Also, this model has accurate performance in large basins. Copyright © EM International.


Lack S.,Islamic Azad University | Marani N.M.,Islamic Azad University | Mombeni M.,Islamic Azad University at Ramhormoz
Advances in Environmental Biology | Year: 2012

This research was conducted in order to investigate the effects of planting date on the grain yield and yield components of three rice cultivars in Khouzestan climatic conditions (South-west Iran) this research was conducted as a split plot using Randomized Complete Block Design (RCBD) with three replications in the 2010 cropping season in the research field of Khuzestan Agricultural Research and Natural Resources Center(Shavoor agricultural research station). In this research the dates 5 th May 25 th May and 15 th June were considered as the main factor in the main plots and the rice cultivars Hamar RedAnbarbou and Danial were regarded as the secondary factors in the sub plots.The results showed that planting date significantly affected grain yield biological yield harvest index 1000 grain weight fertility percentage the number of filled grains per panicle and the number of fertile tillers. The second planting date exhibited the highest grain yield with an average of 6018.3 kgha -1 and the first planting date assumed the lowest grain yield. The cultivars had a significant difference in terms of the abovementioned attributes. Danial and Hamar cultivars featured the highest grain yield with averages of 5591 and 55549 kgha -1 respectively; the lowest amount belonged to Red Anbarbou cultivar.Theinteraction effects of planting date and cultivar was significant on all attributes except for panicle length. The highest grain yield belonged to Danial cultivar in the second planting date with an average of 6902.6 kgha -1 while the lowest was obtained for Red Anbarboucultivar on the first planting date. Both delayed and early planting resulted in the decline of grain yield of rice cultivars. The reason for these reductions was the shortening of the vegetative growth period in delayed planting andthe coincidence of the flowering stage with environmental high temperaturesin earlier planting dates compared to the desirable state. Thus Danial cultivar on the second planting date is recommended for cropping in Khouzestan climate conditions.


Fuladipanah M.,Islamic Azad University at Ramhormoz | Jorabloo M.,Islamic Azad University at Garmsar
Ecology, Environment and Conservation | Year: 2014

Water flow management is one of the most important parts of river engineering. Non-uniformity distribution of rainfall and various flow demand with unreasonable flow management will be caused destroyed of river ecosystem. Then, it is very serious to determine ecosystem flow requirement. In this paper, four hydrological based environmental flow assessment methods have been used to calculate environmental flow in Gharasou River, Ardabil, Iran as following: Flow duration curve indices method, Range of variability approach, Tessman method, and Global environmental flow calculator. In the first method, Q90 and Q95 for different return periods were calculated. Their magnitude were determined as 1-day, 3-day, 7-day and 30 day. Accordingthe second method, hydraulic alteration indices often had low and medium range. In order to maintain river at an acceptable ecological condition, July based flow was selected as environmental flow, i.e. 15 m3s-1. Using Tessman method, minimum and maximum values of monthly environmental flow was estimated 1.8 and 13.72 m3s-1, respectively. Based on the last method, seven scenarios were studied. Of all scenarios, scenario C indicates moderate situation of ecological habitat of river, according to calculations, the amount of the C scenario was determined as 6 m3s-1. Copyright © EM International.


Sedighi H.M.,Islamic Azad University at Ramhormoz | Reza A.,Islamic Azad University at Ramhormoz | Zare J.,Islamic Azad University at Ramhormoz
Journal of Vibroengineering | Year: 2012

This research presents the application of modern analytical approaches for the nonlinear vibrations of cantilever beams. These methods are Homotopy Analysis Method, Parameter Expansion Method and Bubnov-Galerkin Weighted Residual Method. Powerful analytical methods are used to obtain frequency-amplitude relationship of dynamic behavior of the mentioned system. It is demonstrated that one term in series expansions of all methods are sufficient to obtain a highly accurate solution. Finally, a comparison with numerical methods is provided in order to confirm the soundness of the obtained results. © VIBROENGINEERING.


In order to study the effect of restricted irrigation systems and different amounts of potassium fertilizer on water use efficiency and yield of rapeseed (Brassica napus L.), an experiment was conducted in an arid area in Khuzestan, Iran in 2013. The main plots consisted of three irrigation methods: FI (full irrigation), alternate furrow irrigation (AFI) and fixed furrow irrigation (FFI). Each subplot received three rates of K fertiliser application: 0, 150 or 300 kg ha-1. The results showed that the plots receiving full irrigation produced significantly higher grain yield, 1000-kernel weight and grain number per pod than both alternate treatments. However, the highest WUE was obtained with alternate furrow irrigation and 300kg K ha-1 and the lowest was found in the FI treatment and 0 kg K ha-1. Potassium application increased RWC in alternate furrow irrigation and fixed furrow irrigation more than the FI treatment. Maximum oil content was observed in those treatments where full irrigation was applied while minimum oil content was produced in FFI irrigated treatments. Potassium fertilizer also increased grain oil by 15% over the control. Deficit irrigation reduced oleic acid and erucic acid; however oleic acid and linoleic acid increased with increasing potassium. © 2016, Universidad de Tarapaca. All rights reserved.


Sedighi H.M.,Islamic Azad University at Ramhormoz | Reza A.,Islamic Azad University at Ramhormoz | Zare J.,Islamic Azad University at Ramhormoz
International Journal of Physical Sciences | Year: 2011

New analytical work on the well-known preload nonlinearity using the innovative equivalent function (EF) is presented in this paper. The nonlinear vibration of cantilever beam with nonlinear boundary condition in the presence of preload spring with cubic nonlinearity is studied. The powerful analytical method, called He's Parameter Expanding Method (HPEM) is used to obtain the exact solution of dynamic behavior of the mentioned system. It is shown that one term in series expansions is sufficient to obtain a highly accurate solution. Finally, we successfully compare our analysis with numerical solutions. © 2011 Academic Journals.


Barati J.,Islamic Azad University at Ramhormoz | Mortazavi S.S.,Shahid Chamran University | Saidian A.,Shahid Chamran University
International Review of Electrical Engineering | Year: 2010

This paper investigates and compares the enhancement of damping the power system oscillations via coordinated design of the power system stabilizer (PSS), Thyristor Controlled Series Compensation (TCSC) and Static Var Compensator (SVC) controllers. The design problem of FACTS-based stabilizers is formulated as an optimization problem. The proposed approach employs genetic algorithm (GA) for stabilizer parameters optimization. In this paper eigenvalue analysis method is used for small signal stability of single machine infinite bus (SMIB) system installed with PSS, TCSC and SVC. The proposed stabilizers are tested on a weakly connected power system with loading conditions. The eigenvalue analysis and non-linear simulation results are presented and to show and compare the effects of these FACTS-based stabilizers and reveal that TCSC-based stabilizers is much better than SVC-based stabilizers on the damping power system oscillations. © 2010 Praise Worthy Prize S.r.l. - All rights reserved.


Bahrani A.,Islamic Azad University at Ramhormoz | Pourreza J.,Islamic Azad University at Ramhormoz
Bangladesh Journal of Botany | Year: 2014

Foliar application of micronutrients like iron, zinc and manganese significantly increased 1000-kernel weight, grain yield, oil content of seed and harvest index of Brassica napus L. cv. Talayeh. Changes in grain yield was primarily due to the number of pod per plant and that of oil yield was due to grain yield. In general, applying two parts per thousand of the micronutrient was the best treatment to obtain high qualitative and quantitative yield in cv. Talayeh in this region.


Abdi N.,Islamic Azad University at Ramhormoz | Fuladipanah M.,Islamic Azad University at Ramhormoz
Ecology, Environment and Conservation | Year: 2014

Sediment load estimation is one of the challenges of river engineering. More researches have been conducted to develop a perfect model to sediment transport simulation. Analytical and data-driven models are two main groups of models. In this paper, one dimensional fully coupled model and artificial neural network models performance is compared in sediment rating curve simulation in Ahwaz station, Karoonriver, Iran. 1D fully coupled model has calibrated and validated using Nash-Sutdiffe coefficient. The magnitude of 0.15 and 0.19 of NS coefficient for calibration and validation periods of coupled model represent good agreement of the model with average condition of river. According to calculation, derived sediment rating curve using ANN with FFBP algorithm, has good agreement with measured rating curve. In high flows, both two models have difference with measured data. In general ANN model has more accuracy than coupled model. Copyright © EM International.


Tamoradi F.,Islamic Azad University at Ramhormoz | Moohamadmosaee J.,Islamic Azad University at Ramhormoz
Advances in Environmental Biology | Year: 2014

In this paper, various methods of financing and percentage changes in the cost of capital of listed companies on the Stock Exchanges, and the relationship between them are examined. In order to achieve this objective the definition of capital expenditures, weighted average cost of capital, the items constituting the weighted average cost of capital, the test statistic t, the test statistic f and correlation coefficient paid and consequently, it is explained how to calculate each. The research sample which consisted of 128 firms is in the time domain of 2009 to 2012 that are from firms in Tehran Stock Exchange. These results indicate that there is a significant relationship between the method of financing and capital cost rates however, varies the significance of this relationship depending on the method of financing and year of maturity. Also location of long-term debt financing leads to lower cost of capital and consequently increases shareholders wealth. Therefore, administrators, particularly with regards to the inflation conditions of country should try to be financed from the source location. © 2014 AENSI Publisher All rights reserved.

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