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Azizi S.,Islamic Azad University at Yasuj | Ahmadloo E.,Islamic Azad University at Darab
Applied Thermal Engineering | Year: 2016

An artificial neural network model was developed to predict convective heat transfer coefficient (HTC) during condensation of R134a in an inclined smooth tube for the entire range of inclination angles at different saturation temperatures and regardless of flow pattern. The network was designed and trained using a total of 440 experimental data points collected from the literature. Inclination angle, mass flux, saturation temperature and mean vapor quality were used as input variables of multiple layer perceptron (MLP) neural network, while the corresponding HTC was selected as its output variable. By trial-and-error method, MLP network with 18 neurons in the hidden layer was achieved as optimal structure of the ANN which made it possible to predict the HTC with a high accuracy. Mean absolute percent error (MAPE) of 1.48% and correlation coefficient (R) of 0.997 for training data and MAPE of 1.94% and R value of 0.995 for testing data were obtained. Also, 95% and 99% all data were within ±5% and ±7% error band, respectively. MAPE of 1.61% and R value of 0.9963 were calculated for all data. These results confirm the high ability of the ANNs for predicting the HTC values for the entire range of inclination angles and independent of the flow pattern. © 2016 Elsevier Ltd

Ahmadloo E.,Islamic Azad University at Darab | Azizi S.,Islamic Azad University at Yasuj
International Communications in Heat and Mass Transfer | Year: 2016

This paper presents a 5-input artificial neural network (ANN) model for the prediction of the thermal conductivity ratio of nanofluids to the base fluid (knf/kf) of various nanofluids based on water and ethylene glycol (EG) and a type of transformer oil. The studied nanofluids are Al2O3-Water, Al-Water, TiO2-Water, Cu-Water, Cuo-Water, ZrO2-Water, Al2O3-EG, Al-EG, Cu-EG, Cuo-EG, Mg(OH)2-EG, Al2O3-Oil, Al-Oil, Cuo-Oil and Cu-Oil (15 nanofluids). The network is designed and trained using a total of 776 experimental data points collected from 21 sources of experimental data available in the literature. Average diameter, volume fraction, thermal conductivity of nanoparticles and temperature as well as some appropriated numbers for both nanoparticle and base fluid are chosen as input variables of the network, whereas the corresponding value of (knf/kf) is selected as its target. The developed optimal ANN model shows a reasonable agreement in predicting experimental data with mean absolute percent error of 1.26% and 1.44% and correlation coefficient of 0.995 and 0.993 for training and testing data sets, respectively. © 2016 Elsevier Ltd.

Amiri-Khorasani M.,Shahid Bahonar University of Kerman | Sotoodeh V.,Islamic Azad University at Darab
Journal of Sports Medicine and Physical Fitness | Year: 2013

Aim. The purpose of this study was to compare the acute effects of different stretching methods on acceleration, speed, agility, power, and flexibility in different soccer positions. Methods and results. Therefore, 16 soccer players conducted 10 m, 20 m, shuttle run agility, vertical jump, and V-sit flexibility after static (SS), dynamic (DS), combined (static + dynamic) (CS), and no stretching (NS). Relative to the no-stretching condition, there were significant differences in fitness performances after (1) DS vs. SS, (2) DS vs. CS, and (3) CS vs. SS in defenders, midfielders, strikers, and also in all players (P<0.05). Conclusion. In conclusion, it may be desirable for soccer players to perform DS during warm up prior to the performance of activities that require a high power output.

Kharchineh B.,Islamic Azad University at Darab | Ettelaee M.,Islamic Azad University at Tehran
2nd International Conference on Future Networks, ICFN 2010 | Year: 2010

In designing an electronic voting protocol factors such as security, simplicity, justice, and easily communicate should be considered. In general, an electronic voting protocol security how is higher, is more complex, but this problem has been solved because of the new protocol using a fixed blind signature scheme. The advantage of this protocol in the same samples that the same simply has higher security level. This protocol is also designed so that the voters could be considered of their votes to be safe and no part can not alone be aware of his votes. This will cause that voters can trust to the system, justice and democracy is respect. On The other hand the type of algorithms used in this plan has the lowest rate of change is that the information on each type of connection and even mobile can be implemented. © 2010 IEEE.

Sohrabi M.R.,Islamic Azad University at North Tehran | Matbouie Z.,Islamic Azad University at Darab | Asgharinezhad A.A.,Shahid Beheshti University | Dehghani A.,Iran University of Science and Technology
Microchimica Acta | Year: 2013

We describe a novel magnetic metal-organic framework (MOF) for the preconcentration of Cd(II) and Pb(II) ions. The MOF was prepared from the Fe3O4-pyridine conjugate and the copper(II) complex of trimesic acid. The MOF was characterized by IR spectroscopy, elemental analysis, SEM and XRD. A Box-Behnken design through response surface methodology and experimental design was used to identify the optimal parameters for preconcentration. Extraction time, amount of magnetic MOF and pH value were found to be critical factors for uptake, while type, volume, concentration of eluent, and elution time are critical in the elution step. The ions were then determined by FAAS. The limits of detection are 0.2 and 1.1 μg L-1 for Cd(II), and Pb(II) ions, respectively, relative standard deviations are <4.5% (for five replicates at 50 μg L-1 of Cd(II) and Pb(II) ions), and the enrichment capacity of the MOF is at around 190 mg g-1 for both ions which is higher than the conventional Fe3O4-pyridine material. The magnetic MOF was successfully applied to the rapid extraction of trace quantities of Cd(II) and Pb(II) ions in fish, sediment, and water samples. © 2013 Springer-Verlag Wien.

Hajian R.,Islamic Azad University at Gachsaran | Ekhlasi E.,Islamic Azad University at Gachsaran | Daneshvar R.,Islamic Azad University at Darab
E-Journal of Chemistry | Year: 2012

The interactions between epirubicin (EPR) and double stranded DNA (ds-DNA) have been studied by UV-Vis spectrophotometry, cyclic voltammetry, fluorescence spectroscopy and viscometery. The apparent binding constant of epirubicin with DNA was found to be 3.8 × 10 5 mol -1 L and was studied at different temperatures. It indicated that the former method could be successfully applied to the determination of epirubicin. Also, the voltammetric behavior of EPR was investigated at glassy carbon electrode using cyclic voltammetry. Thermodynamic parameters including δH 0, δG 0 and δS 0 were determined as -5.7×10 4, -3.13×10 4 J mol -1 and -87.96 J mol -1 K -1 respectively. One indication of the strong interaction between DNA and EP was increasing of viscosity. The diffusion coefficients of EP in the absence (D 0) f and presence of ds-DNA (D o) b was calculated as 5.04×10 -6 and 1.13×10 -6 Cm 2 s -1 respectively. According to the thermodynamic parameters, the main binding force could be judged. The experimental results revealed that EPR and ds-DNA had strong interactions. The mechanism of quenching belonged to static quenching and the main sort of binding force was intercalation.

Azam S.H.M.,Islamic Azad University at Darab | Ahmadloo E.,Islamic Azad University at Darab
Materials and Manufacturing Processes | Year: 2016

Machining is obviously indispensable to industrial manufacture, a process whereby a workpiece takes its planned shape after proper chip removal. The type and the size of a chip from such a process are determined by a set of factors, the analysis of which can provide valuable insights into the cutting process. In this study, a new quick-stop device (QSD) for chip removal was designed, manufactured, and employed in an analysis of chip formation in chip removal with cutting tool at varying cutting speeds. The samples competently illustrate the differences in the formation of chips at various cutting speeds. Depending on material and cutting conditions, a chip may be continuous or discontinuous. Employing metallographic techniques, the present study analyzed the orthogonal cutting of aluminum 5000 with cutting tool. During the experiments, the built-up edges (BUEs), the surface quality, and the interactions among machining parameters were observed. At the end, a frozen chip with a BUE was divided into seven sections. The results show that the new QSD is effective and BUEs have a direct effect on the quality of a workpiece's surface and additionally can increase the penetration depth and machining forces. 2016 Copyright © Taylor & Francis Group, LLC

Khorsandi F.,Islamic Azad University at Darab | Yazdi F.A.,Yazd Agriculture and Natural Resources Research Center
Communications in Soil Science and Plant Analysis | Year: 2011

Texture and salt type influence the relationships between saturated paste electrical conductivity (ECe) and EC of other soil/water ratios. The objectives of this study were to develop and validate relationships between ECe and EC1:5 suspension for soils in Yazd Province and evaluate the effects of soil texture and gypsum on those relationships. Three hundred twenty-two soil samples were collected, of which 272 (all data) were used to develop the models and 50 were used to validate them. The soils were divided into two general textural categories of coarse and fine and two categories of with (G) and without gypsum (NG). Gypsum content had a stronger impact on the accuracy of the suspension method in predicting ECe than texture. The ECe = 5.60 EC1:5 - 4.37 and ECe = 5.37 EC1:5 + 0.57 models are recommended for soils with and without gypsum, respectively. The methodology can be implemented in other regions, particularly if gypsum is present. © Taylor & Francis Group, LLC.

Haghighat-Jahromi M.,Islamic Azad University at Darab | Nahid S.,Islamic Azad University at Darab
Asian Journal of Animal Sciences | Year: 2011

As the dairy industry continues to strive for increased genetic gains in milk production, cows will continue to be at increased risk of developing ketosis. Subclinical ketosis is defined as increased levels of circulating ketone bodies without the presence of clinical signs of ketosis. In this study, subclinical ketosis incidence in dairy cows in Fars province of Iran and its correlation with some reproductive performance values was investigated. A total of 167 cows in 14 Holstein crossbreed herds were monitored for subclinical ketosis in a period of calving to 70th day postpartum, weekly. Milk samples were collected and the level of milk ketone bodies was determined qualitatively by the use of nitroprusside milk test. The incidence rate of subclinical ketosis was 7.2% (percent of cows with at least one positive test) in early lactation (0-70th day) period and the peak prevalence of subclinical ketosis occurred during the fourth week of lactation and there was no significant difference between positive and negative groups in reproductive performance values. © 2011 Knowledgia Review, Malaysia.

Akbari A.,University of Technology Malaysia | Talebanfard S.,Islamic Azad University at Darab | Hassan A.,University of Technology Malaysia
Polymer - Plastics Technology and Engineering | Year: 2010

Nanocomposites formation brings about an enhancement of many properties for polymers. They have attracted interests since they attain significant properties with far less clay content. It is generally assumed that exfoliation nanocomposites are preferred for the greatest increases in properties, but that is not correct in flame retardency properties. In this paper the effects of different types of clays and clay modifiers on final morphology of PS/clay nanocomposites were reviewed. Clay charge density and length, bulk, polarity, functional groups and polymerizability of the clay modifier are very significant in their efficiency and final morphology of PS/Clay nanocomposite. © Taylor & Francis Group, LLC.

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