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Estimation of Saturation Percentage of Soil Using Multiple Regression, ANN, and ANFIS Techniques
Khaled Ahmad Aali,Masoud Parsinejad,Bizhan Rahmani
Computer and Information Science , 2009, DOI: 10.5539/cis.v2n3p127
Abstract: The saturation percentage (SP) of soils is an important index in hydrological studies. In this paper, arti?cial neural networks (ANNs), multiple regression (MR), and adaptive neural-based fuzzy inference system (ANFIS) were used for estimation of saturation percentage of soils collected from Boukan region in the northwestern part of Iran. Percent clay, silt, sand and organic carbon (OC) were used to develop the applied methods. In additions contributions of each input variable were assessed on estimation of SP index. Two performance functions, namely root mean square errors (RMSE) and determination coefficient (R2), were used to evaluate the adequacy of the models. ANFIS method was found to be superior over the other methods. It is, then, proposed that ANFIS model can be used for reasonable estimation of SP values of soils.
On the possibility of magnetic field detection on a microlensed source star
Ahmad Mehrabi,Habib khosroshahi,Hadi Rahmani
Physics , 2015,
Abstract: In a microlensing event, a large magnification occurs at caustic crossing and provides an opportunity to obtain a stronger signal associated with the object. In this paper we study the possibility of magnetic field detection in a microlensing event through the Zeeman effect. We follow the prescription introduced by \citep{Robinson:1980} which analyses the spectrum of a star in a Fourier space to deconvolve other broadening mechanism from the actual Zeeman effect. First we study magnification contrast between source and spot in terms of spot size and then consider two distinct strategies using modern spectrographs and perform a Monte Carlo simulation to find the detection efficiency in magnification-magnetic field plan. The spectral resolution and signal to noise ratio in each strategies, specify suitable places in this plane to detect a magnetic field. Apart from complexity of magnetic field on a star, we consider a simple model and propose a fantastic method to detect magnetic field using spectrum of source stars at caustic crossing.
Prevalence and Predisposing Factors of Retinopathy of Prematurity in Very Low-Birth-Weight Infants Discharged from NICU
Reza Saeidi,Ahmad Hashemzadeh,Sina Ahmadi,Shagayeg Rahmani
Iranian Journal of Pediatrics , 2009,
Abstract: Objective: Retinopathy of prematurity (ROP) is a disease of the eye caused by disorganized growth of retinal blood vessels resulting in scarring and retinal detachment. All preterm babies are at high risk for ROP, and very low birth weight is an additional risk factor. An increased incidence of ROP is expected in Iran because of improved survival of low birth weight and premature babies, and it is obvious that pediatricians and ophthalmologists are concerned about prevention and timely treatment of ROP in these children. To asses the real situation of ROP in our NICU we studied its prevalence and risk factors. Methods: This was a retrospective analysis of premature infants with birth weight of ≤1500 grams or gestational age of ≤32 weeks, admitted April 1, 2005 to March 28, 2006, to the Neonatal Intensive Care Unit of Qaem Hospital, Mashhad, Iran. The collected data of 47 cases in this cross-sectional study are analyzed by SPSS (Mann_Whitney, t-Student). Findings: Forty five infants were included in the study. Out of these, 4 (8.5%) developed ROP (inclusive all stages). Our analysis revealed that low gestational age, sepsis and respiratory distress syndrome were independent predictors for the development of ROP. Conclusion:The frequency of ROP in our hospital was lower than the range reported in developed countries, and our risk factors were a little different.
Comparison of flora, life forms and chorology in the two untouched and degraded sites in Beech forests (Case study: Shafaroud forests.Gilan,Iran)
Beitollah Amanzadeh,Mohammad Reza Pourmajidian,Ahmad Rahmani,Aiuob Moradi
International Journal of Forest, Soil and Erosion , 2013,
Abstract: : In order to study on environmental changes effects on understory vegetation, two untouched and degraded sites were evaluated in Shafaroud forests. Three sampling plots (one hectare in each site) were selected and each plot divided to four sub-plots (10*10m).In each Sub-plot plant samples were collected and identified using different flora references. Results showed that a total 45 species were known from untouched area that belong to 28 families and 39 genera. 32(71%) dicotyledones ,8 (18%) monocotyledones and 5 (11%) pterydophyta were identified. Lamiacea with four species was the highest number species.17 families have only one species. Flora of degraded site includes 74 species (60 (80%) dictyledones, 9 (12%) monocotyledones and 5 (8%) pterdophyta) that belong to 32 families and 62 genera. Asteraceae with 9 species are the most abundant in this area. Also 7 species of Lamiaceae family were identified in degraded area. hemichryptophytes are the most frequent life forms in the both areas. From the view of geographical distribution, plants of untouched area included 69% species belonging to Euro-Sibrean and only 2.5% species belonging to Cosmopolitan while in degraded area 51% and 3.5% species belaged to Euro-Sibrean and Cosmopolitan, respectively. Key Words: degraded ecosystems, life forms , chorology Caspian forests
Investigation of Water Disinfection by Electrolysis
Ali Reza Rahmani,Ahmad Jonidi Jafari,Amir Hossein Mahvi
Pakistan Journal of Biological Sciences , 2005,
Abstract: The main purpose of this study was to conduct experimental investigation of water disinfection by using the electrolysis method. Inactivation and killing Coliform in polluted waters are investigated by different voltage, electrodes (Al, St and Cu) and 5 min electrolyze time. The experimental results showed that the removal efficiency depends on the voltage and electrode materials. From the experiments carried out at 10 V and at current intensity of 135 mA, it was found that 5 min period was sufficient for disinfecting water by Stainless steel electrodes.
Effectiveness of photochemical and sonochemical processes in degradation of Basic Violet 16 (BV16) dye from aqueous solutions
Rahmani Zahra,Kermani Majid,Gholami Mitra,Jafari Ahmad
Iranian Journal of Environmental Health Science & Engineering , 2012, DOI: 10.1186/1735-2746-9-14
Abstract: In this study, degradation of Basic Violet 16 (BV16) by ultraviolet radiation (UV), ultrasonic irradiation (US), UV/H2O2 and US/H2O2 processes was investigated in a laboratory-scale batch photoreactor equipped with a 55W immersed-type low-pressure mercury vapor lamp and a sonoreactor with high frequency (130kHz) plate type transducer at 100W of acoustic power. The effects of initial dye concentration, concentration of H2O2 and solution pH and presence of Na2SO4 was studied on the sonochemical and photochemical destruction of BV16 in aqueous phase. The results indicated that in the UV/H2O2 and US/H2O2 systems, a sufficient amount of H2O2 was necessary, but a very high H2O2 concentration would inhibit the reaction rate. The optimum H2O2 concentration was achieved in the range of 17 mmol/L at dye concentration of 30 mg/L. A degradation of 99% was obtained with UV/H2O2 within 8 minutes while decolorization efficiency by using UV (23%), US (<6%) and US/H2O2(<15%) processes were negligible for this kind of dye. Pseudo-first order kinetics with respect to dyestuffs concentrations was found to fit all the experimental data.
THE EFFECTS OF PNF & STATIC STRETCHING ON KNEE ROM OF AMPUTEE ATHLETES
Hassan Daneshmandi,Ahmad Ebrahimi Atri,Ali Ghasemi,Pegah Rahmani
Brazilian Journal of Biomotricity , 2011,
Abstract: DANESHMANDI, H.; ATRI, A. E.; GHASEMI, A.; RAHMANI, P. The effects of PNF & static stretching on knee ROM of amputee athletes. Brazilian Journal of Biomotricity. v. 5, n. 4, p. 255-262, 2011. Flexibility is one of the most important factors in athletic preformance injuries prevantion especially in rehabilatation of athletic disabled. In order to maintain and develop ROM in an amputated limb, the superior joint of the stump should be under effective stretching exercises. Therefore the purpose of the present study was to compare the effects of two methods of static stretching and PNF (HR) on increasing the knee ROM of B.K. amputee athletes. The subjects were consisted of 19 B.K. male amputated athletes, with mean age of 35± 5years; and mean stump length of 19± 7 cm., which they were randomly divided into two groups of static stretching exercises (N=9); and PNF exercises (N=10). ROMs were measured by use of a"Lighton Flexometer".The exercise protocol of both groups consisted of 12 sessions of 20 minutes. Results were concluded in both training programs of static stretching method and PNF (HR), the ROM of the knee joint increased significantly (P≤ 0.05). There was no significant difference between two methods of stretching exercises. The present study showed the effects of flexibility exercises on improvement of ROM of knee joint of B.K amputees. Therefor it emphasizes the requirements of performing static stretching exercises and PNF exercises by the coaches in order to improve physical condition of amputees and to rehabilitate them.
Element Free Gelerkin Method for 2-D Potential Problems  [PDF]
Ali Rahmani Firoozjaee
Applied Mathematics (AM) , 2015, DOI: 10.4236/am.2015.61015
Abstract: A meshfree method namely, element free Gelerkin (EFG) method, is presented in this paper for the solution of governing equations of 2-D potential problems. The EFG method is a numerical method which uses nodal points in order to discretize the computational domain, but where the use of connectivity is absent. The unknowns in the problems are approximated by means of connectivity-free technique known as moving least squares (MLS) approximation. The effect of irregular distribution of nodal points on the accuracy of the EFG method is the main goal of this paper as a complement to the precedent researches investigated by proposing an irregularity index (II) in order to analyze some 2-D benchmark examples and the results of sensitivity analysis on the parameters of the method are presented.
Comparison of growth, nutrition and soil properties of pure stands of Quercus castaneifolia C. A. Mey. and mixed with Carpinus betulus L. in the Hyrcanian forests of Iran
Seyed Mohsen Hosseini,Einollah Rouhi-Moghaddam,Ezzatollah Ebrahimi,Ahmad Rahmani
Ecologia Balkanica , 2011,
Abstract: In the present study, Quercus castaneifolia (Oak, as target species) and Carpinus betulus (Horn beam, as native component species) were planted in five proportions (100Q, 70Q:30C, 60Q:40C, 50Q:50C, 40Q:60C) in the Noor region (North Iran). After 12 years, the effects of the species on the growth of the trees, nutrient concentrations in the live and senescent leave and on soil properties were assessed. The results showed the survival and diameter at breast height (dbh) of the individual Oak trees were positively affected by the presence of Horn beam. Percent retranslocation of the nutrients in Quercus trees was: K>N>P. Leaflitter fall production ranged from 4.70 to 6.80 Mg ha1 year 1. N concentration in fully expanded leaves, N and Ca concentrations in the senescent leaves of Quercus trees and N concentration in topsoil were higher in some of the mixed plantations than in the monocultures of the Quercus trees. N fluxes, N and P etranslocation, and soil P concentrations in the monocultures were intermediate relative to mixed plantations. The obtained results somewhat indicated that the mixing with hornbeam increased the productivity and sustainability of the oak sites. Within the framework of this experiment, it appeared that production was maximized when these two species were grown together in the proportion of 50% Quercus castaneifolia and 50% Carpinus betulus.
The Regeneration Structure and Biodiversity of Trees and Shrub Species in Understory of Pure Plantations of Oak and Mixed with Hornbeam in the Hyrcanian Forests of Iran
Einollah Rouhi-Moghaddam,Seyed Mohsen Hosseini,Ezzatollah Ebrahimi,Ahmad Rahmani
Pakistan Journal of Biological Sciences , 2007,
Abstract: The regeneration structure and biodiversity of trees and shrub species in under story of pure and mixed Oak plantations were investigated in Chamestan Forest and Rangeland Research Station of Iran. Planted species including Oak (as main species) and Hornbeam (as associated species). This species were planted in five proportions (100Q, 70Q:30C, 60Q:40C, 50Q:50C, 40Q:60Z) in Northern of Iran in 11 years ago. All of regenerating seedlings and saplings of woody plants were divided into two height classes of 15-200 cm and more than 200 cm. In biodiversity study dominance index of Berger-Parker, diversity index of Fisher alpha, richness index of Margalef and evenness index of Equitability J were used. The results showed that abundance and diversity of regenerated species in under story of all plantations of oak were more than unplanted control plots and also under 50Q:50C were more than pure stand of oak. The presence of primary forest species in under stories of mixed plantation showed the usage of these plantations in development of succession in natural forests.
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