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Open Access Article
1 - Combined Estimating Influence Probabilities for an Influence Maximization Problem in Social Networks and Its Application in the Power Industry
Sohameh Mohammadi .Mohammad H Nadimi-Shahraki Zahra Beheshti kamran zamanifarNowadays, online social networks have an inseparable connection with the daily life of many people in the world. The applications of social networks are increasing in businesses for advertising, marketing, and recommender systems, as well as in resource and energy consu MoreNowadays, online social networks have an inseparable connection with the daily life of many people in the world. The applications of social networks are increasing in businesses for advertising, marketing, and recommender systems, as well as in resource and energy consumption management systems. One of the most important problems in the information diffusion process of social networks is the influence maximization. In recent years, some research has been conducted to improve the prediction quality of information diffusion models in this problem. In a review of existing models, the influence probabilities among users are estimated unrealistically. In this research, a new method has been proposed to determine the influence probabilities among social network users. This method is a combination of two main approaches in the calculation of influence probabilities, including the use of an action log table and the uniform method with a predetermined value. The performance of the proposed method was evaluated and compared with competitive methods on different real-world social network data sets. The results of the experiments show that the proposed method can increase the efficiency of the predictions in solving the influence maximization problems. Manuscript profile -
Open Access Article
2 - Conceptual Model For New Product Development In Concurrent Engineering Environment
S. M. Seied Hoseini S. J. IranbanToday necessary and important of new product, conversion as a necessary strategy for stay in business.Chief companies try to use new approaches for improvement of new product development (NPD) process.One of these new approaches is concurrent engineering (CE). Many rese MoreToday necessary and important of new product, conversion as a necessary strategy for stay in business.Chief companies try to use new approaches for improvement of new product development (NPD) process.One of these new approaches is concurrent engineering (CE). Many researches and studies about thisapproach was carried out or is doing now. In the general perspective, concurrent engineering presenting thepattern that have three aspects of design, production and customer. In other words, concurrent engineeringapproaches try to consider the design, manufacturing and customer of product for achievement thesignificant improvements in business. In this article try to consideration all three aspects of concurrentengineering and finally presenting the conceptual model of new product development (NPD) in thisenvironment. Manuscript profile -
Open Access Article
3 - “Evaluating the theory of ‘‘diffusion of innovations’’ in respect to consumers’ time of adoption (electronics industry)”
H. Nikoomaram H. Nezakati AlizadehAim of this research is evaluation of “Diffusion of Innovations Theory” in relation with Electronicsconsumers' adoption. To do so, a population of Iranian TV-set manufacturers is studied. Five majorcompanies, holding 95% of market share have been chosen. Sel MoreAim of this research is evaluation of “Diffusion of Innovations Theory” in relation with Electronicsconsumers' adoption. To do so, a population of Iranian TV-set manufacturers is studied. Five majorcompanies, holding 95% of market share have been chosen. Selection of main variables has been based on acategorization by the Ministry of Mine and Industry in three groups of products (14", 21" and 29" TV-sets).Due to the confidential nature of data and to facilitate generalizing and deducing, all data have been coded.Tests and analyses relating to research hypothesis have been lead to this conclusion that distribution curve ofDiffusion of Innovations in Electronic Industry (TV-sets), like the global pattern, does follow the normalcurve. But categorizing various types of adopters does not follow a global pattern; distribution beneath thecurve (Adopters Classifications) shows following record:- Lack of innovators is observed.- Early adopters and laggards mark a level higher than normal.- Early majorities and late majorities show a level lower than the normal limit. Manuscript profile -
Open Access Article
4 - Effect of different sizes of balls on crystalline size, strain, and atomic diffusion on Cu-Fe nanocrystals produced by mechanical alloying
Mohammad Reza Vaezi Seyed Hesam Mir Shah Ghassemi Ali Shokuhfar -
Open Access Article
5 - Atomic transport and surface properties of some simple liquid metal using one component plasma system
Yogeshkumar A Sonvane Pankajsinh B Thakor Ashwin R Jani -
Open Access Article
6 - The impact of AsH3 overflow time and indium composition on the formation of self-assembled InxGa1 − xAs quantum dots studied by atomic force microscopy
Didik Aryanto Zulkafli Othaman Abd Khamim Ismail -
Open Access Article
7 - Thermoelectric power of metallic Rb3C60: phonon-drag and carrier diffusion contributions
Dinesh Varshney Namita Singh -
Open Access Article
8 - Dynamical and transport properties in plasmas including three-particle spatial correlations
Hakima Ababsa Med Tayeb Meftah Thouria Chohra -
Open Access Article
9 - Ripple transport and neoclassical diffusion in IR-T1 tokamak
M. Hosseininejad M. Ghoranneviss M. K. Salem -
Open Access Article
10 - Exactly solvable reaction diffusion models on a Bethe Lattice through the empty-interval method
Laleh Farhang Matin -
Open Access Article
11 - Public Policy Palette: A Mixed Study of Meta-synthesis and Delphi Technique
Nima Eskandarinia Caramollah Daneshfard Abolhasan FaghihiAbstract Background: Nowadays, Public Policy Knowledge has been faced many new approaches including adaptive policy approach, public policy network approach, closed innovation diffusion policy approach & open innovation diffusion policy approach. The ability to choo MoreAbstract Background: Nowadays, Public Policy Knowledge has been faced many new approaches including adaptive policy approach, public policy network approach, closed innovation diffusion policy approach & open innovation diffusion policy approach. The ability to choose the right approach between adaptive policy approach, public policy network approach, closed innovation diffusion policy approach & open innovation diffusion policy approach in this condition is very important Objective: Proposing a contingency framework to choose the right approach between Stage process model, policy network approach, policy innovation diffusion and adaptive approach Method: Qualitative Research Method by means of mixed metasynthesis and Delphi technique. Metasynthesis has been conducted by Sandelowski and barroso (2007) technique & Delphi technique has been recurred 4 times in this research. Findings: Three variables including predictability, participatory and innovativeness can define applicability conditions of each approaches including stage, network, innovation diffusion and adaptive Conclusion: The applicability of each approach is not general and each of them has a unique condition Key Words: Stage Model, Network Approach, Adaptive Approach, Innovation Diffusion Manuscript profile -
Open Access Article
12 - Firmware Development Work on Expanding the Use of Smart Phone Applications
Hossein Maadanipour Ahmad AslizadehCurrent study has done to investigate the effect of smartphone operation systems development on application usage rate as a new media and new marketing channel. For this purpose, the effect has been formulated by diffusion innovation theory of Rogers considering innovat MoreCurrent study has done to investigate the effect of smartphone operation systems development on application usage rate as a new media and new marketing channel. For this purpose, the effect has been formulated by diffusion innovation theory of Rogers considering innovation and technology acceptance context. According to the model, features that cause an innovation and a technology adoption; are relative advantage, compatibility, complexity, trial ability, and visibility of the discussed phenomena. For more acquaintance of different operation systems, the history of creation and development in this field has been explained. Base on data that covered 377 users of an interactive application, correlation has been found. By regression analysis, the effect and coefficient has been proved. Results show that smartphone operation systems development has a positive effect on application usage rate. As a result, acceptor increase and growth rate of actual application users by OS development are more likely predictable. Manuscript profile -
Open Access Article
13 - Turing instability and pattern formation in reaction-diffusion models
َAli AtabaigiPatterns are found everywhere and the past fifty years studies have advanced our understanding of the mechanisms . In this paper, we study those systems that develop temporary patterns. Special emphasis is made on Turing instabilities as one of the most common sources o MorePatterns are found everywhere and the past fifty years studies have advanced our understanding of the mechanisms . In this paper, we study those systems that develop temporary patterns. Special emphasis is made on Turing instabilities as one of the most common sources of pattern formation. Gierer-Meinhardt model acts as one of prototypical reaction diffusion systems describing pattern formation phenomena in natural events. Bifurcation analysis, including theoretical and numerical analysis, is carried out on the Gierer-Meinhardt activator-substrate model. The effects of diffusion on the stability of equilibrium points is investigated. It shows that under some conditions, diffusion-driven instability, i.e, the Turing instability, about the equilibrium point will occur, which is stable without diffusion. These diffusion-driven instabilities will lead to the occurrence of spatially nonhomogeneous solutions. Consequently, some pattern formations, like stripe and spots solutions, will appear. To illustrate theoretical analysis, we carry out numerical simulations. These diffusion-driven instabilities will lead to the occurrence of spatially nonhomogeneous solutions. Consequently, some pattern formations, like stripe and spots solutions, will appear. To illustrate theoretical analysis, we carry out numerical simulations. Manuscript profile -
Open Access Article
14 - A semi-analytic method to solve the oxygen diffusion problem
Mojtaba MoradipourIn this paper, a semi-analytic approach is proposed to solve the oxygen diffusion problem.First, we discretize the partial differential equation of the oxygen diffusion problem in temporal direction using the backward finite difference Euler method. We achieve a sequenc MoreIn this paper, a semi-analytic approach is proposed to solve the oxygen diffusion problem.First, we discretize the partial differential equation of the oxygen diffusion problem in temporal direction using the backward finite difference Euler method. We achieve a sequence of free boundary problems in the form of ordinary differential equations (ODEs) in the spatial direction. The ODEs are then solved analytically and a recursive formula is presented to compute the solutions of the ordinary differential equations. The problems of finding unknown boundaries are reduced to nonlinear algebraic problems. Finally, the nonlinear algebraic problems are solved using the root-finding methods such as the false position method. The method proposed in this paper is easy to implement and a comparison with other numerical methods shows that the proposed approach is very efficient and gives very accurate numerical results.Some tables and figures are included to show the efficiency and effectiveness of the proposed technique. Manuscript profile -
Open Access Article
15 - Developing a Model for Software-as-a-Service Adoption
E. Haji Ahmadi B. KheiryPurpose: The goal of this paper is to investigate the effective factors on managers’ behavioral intention for software as a service adoption. Methodology: The factors identified from Technology Acceptance Model, Innovation Diffusion Theory and the study of Benlian MorePurpose: The goal of this paper is to investigate the effective factors on managers’ behavioral intention for software as a service adoption. Methodology: The factors identified from Technology Acceptance Model, Innovation Diffusion Theory and the study of Benlian & Hess (2011).The data were collected on top and middle managers using a structured questionnaire. A total of 370 questionnaires were completed. Results are analyzed by structural equation modeling, a path diagram generated and sixteen hypotheses tested using LISREL and SPSS software. Findings: five of the hypotheses were accepted. The results reveal that consumer behavioral intention for saas adoption affected by perceived consumer ease of use, marketing efforts and social influence. Research limitation: Other factors might have been identified and added to the conceptual framework. The timeframe of data collection was very specific. The large sample size and its apparent representativeness encourage confident generalization of the findings. Managerial Implications: marketers now have clear evidence that perceived consumer ease of use, marketing efforts and social influence are important factors that affecting consumer behavioral intention, and should plan their intelligence gathering and campaign strategy accordingly. Manuscript profile -
Open Access Article
16 - Electrocatalytic properties of platinum and it's binary alloy with vanadium in oxygen reduction reaction(ORR)
Mohammad Yari Sajjad Sedaghat Sherehjini -
Open Access Article
17 - Biochemical structure and antibacterial activity of hemolymph in male and female of fresh water prawn (Macrobrachium nipponense (
Karimzadeh, K.*, Zahmatkesh, A., Pormehr, M. .The aim of this study was to characterize the biochemical structure and bactericidal activity of hemolymph Microbrachium in different doses on several human bacterial pathogenFirst 80 individual (40 for male and 40 for female) of prawn (M. nipponense) with an average le MoreThe aim of this study was to characterize the biochemical structure and bactericidal activity of hemolymph Microbrachium in different doses on several human bacterial pathogenFirst 80 individual (40 for male and 40 for female) of prawn (M. nipponense) with an average length of 8.1 ± 0.12 were collected from Anzali wetland. After separation of males and female from each other, hemolymph of samples were taken from ventral sinus of the prawn and structure of collected hemolymph was determined through an electrophoresis and FTIR analysis.The antibacterial activity of M. nipponense hemolymph was investigated against five pathogenic bacteria (Vibrio cholera, Klebsiella pneumonia, Bacillus subtilis, Staphylococcus aureus, Escherichia coli) in doses of 25 to 100 micrograms per liter by disk diffusion method.The electrophoretic pattern of males and females hemolymph revealed presence of proteins with molecular weights between 22-100 Kda. Hemolymph structure contained both secondary regular and irregular protein structures by FTIR analysis. Different doses of hemolymph, indicated inhibitory activity against different bacterial strains. Also significant difference was observed between male and female hemolymph in case of antibacterial activity p <0.05).Highest inhibitory effect of hemolymph was shown against Staphylococcus aureus, Bacillus subtilis and Vibrio cholera in male. While the lowest level of antibacterial activity was recorded in female against Bacillus subtilis and Escherichia coli with zone of inhibition 5.9 ± 0.12 and 6.5 ± 0.08 mmResults of this study indicated that fresh water prawn hemolymph was shown well bactericidal activity and can be a substitute for antibiotic-based chemical drugs. Manuscript profile -
Open Access Article
18 - Study of Kinetic and Isotherm Models of Lead Ions from Aqueous Solution by Montmorillonite and Montmorillonite Modified with HDTMA-Br
Mahboobeh Abolhasani Zeraatkar Hamidreza Rafiei-SarbijanBackground and Aim: Because of its high specific surface area and high cation exchange capacity (CEC), as well as its availability and low price, sodium montmorillonite (Mt) is used as an adsorbent for a wide range of pollutants, including heavy metals and organic compo MoreBackground and Aim: Because of its high specific surface area and high cation exchange capacity (CEC), as well as its availability and low price, sodium montmorillonite (Mt) is used as an adsorbent for a wide range of pollutants, including heavy metals and organic compounds; but the structure of this type of natural clay, however, is unstable, and usually damaged by harmful substances of sewage liquid in the process of infiltration. The organic surfactant hexadecyltrimethylammonium bromide (HDTMA) was used to modify montmorillonite clay to solve this problem. The next step was to investigate lead removal using modified montmorillonite clay (Mt-H). Method: In this study, sodium montmorillonite organic clays modified with hexadecyltrimethylammonium bromide with a CEC two times greater than clay (Mt-H) were prepared. These modified clays were identified using X-ray diffraction, Fourier transform infrared spectroscopy, and field emission scanning electron microscopy. The effect of initial lead concentration on lead adsorption from aqueous solution by two adsorbents (montmorillonite clay and modified montmorillonite clay) was investigated. The lead adsorption process was studied using Langmuir and Freundlich adsorption isotherm models. The mechanisms of lead adsorption were investigated and compared using pseudo-first-order, pseudo-second-order, Elovich, and intraparticle diffusion models. Results: The results showed that the organic surfactant hexadecyltrimethylammonium bromide (Mt-H) successfully modified montmorillonite clay, and the interlayer space of the first order peak in montmorillonite clay increased from 11 to 19.7 Å after modification. According to the findings of this study, increasing the initial concentration of lead increased the amount of lead adsorption (Qi) in both adsorbents, sodium montmorillonite clay (Mt) and modified montmorillonite clay (Mt-H). Surface adsorption of lead in montmorillonite clay (Mt) with the Langmuir model and adsorption in modified montmorillonite clay (Mt-H) with the Freundlich model both showed good agreement with experimental data. According to the results, montmorillonite clay (Mt) adsorbed approximately 40% of the lead ions in the first 80 minutes of the reaction, but surface adsorption of lead by modified montmorillonite clay (Mt-H) reached approximately 40% after 1280 minutes. The maximum monolayer adsorption capacity calculated from the Langmuir model at 30°C in modified montmorillonite clay (Mt-H) was 32.54 mg/g, which was approximately 34% lower than the value obtained in montmorillonite clay (Mt). Surface adsorption in montmorillonite clay (Mt) showed the best fit with the Elovich kinetic model, but modified montmorillonite clay (Mt-H) showed the best fit with the intraparticle diffusion kinetic model. Conclusion: The results showed that adding hexadecyltrimethylammonium organic surfactant to sodium montmorillonite clay reduced its lead adsorption capacity. However, modified clay (Mt-H) adsorbs lead ions more strongly. Manuscript profile -
Open Access Article
19 - Investigating the Spread of Pollution in the Porous Environment of the Babol Aquifer by MODFLOW and MODPATH Models
Yaser Ghandehari Alireza Zamani Nouri Babak AminnejadBackground and Aim: Due to the sharp decline of the underground water in the country's plains due to their indiscriminate extraction for agricultural purposes, managers are looking for solutions to manage and restore underground water tables. One of the solutions to com MoreBackground and Aim: Due to the sharp decline of the underground water in the country's plains due to their indiscriminate extraction for agricultural purposes, managers are looking for solutions to manage and restore underground water tables. One of the solutions to compensate for the drop in the underground water level, which is one of the most effective factors in destroying the discharge capacity and increasing the quality in the underground water area, scenarios of reducing withdrawal of farming wells and prepare prohibition plans with the least uncertainty based on the regional sensitivity to pollution. The purpose of this research is to predict the flow and pollution conditions of the area based on numerical models, so that the level network and the direction of the underground water flow of the plain using MODFLOW software in a long-term period and the development of the prediction model using Calibration and validation operations should be performed on the base period of the studies in order to be able to implement the forecast scenarios by applying restrictions and reducing harvesting on aquifer exploitation resources, and specifically agricultural wells, until the stage of stable hydrograph extraction of the plain.Method: This research was carried out with the aim of estimating and predicting the state of pollution in the urban pollution site, using MODFLOW and MODPATH computer programs in GMS software. To achieve this goal, in the first step, the numerical model of the aquifer flow was prepared and calibrated by the MODFLOW code. Then, the MODPATH code was used to track the contaminated particles in the steady-state progressive method. In the second stage, the impact of the scenario of increasing and decreasing the pumping from the exploitation wells on the travel time, the length of the path and the catchment area of the leachate particles leading to them was predicted and evaluated by the regressive method. In the third step, the tracking of particles leading to qualitative sampling wells in the plain was predicted and evaluated by regressive method in steady state. Results: According to the automatic calibration and validation approach, the underground water flow model produced the least statistical deviation on the optimization parameters. Also, the particle transfer quality model was correctly implemented on the groundwater flow prediction model. In the Babol aquifer, the waste disposal area outside the designated aquifer is saturated. It was observed that, by adjusting the parameters of the simulation of the transfer of residual pollution cloud particles, an estimate of the concentration was applied to the permeable boundaries and the channel network. This means that in the simulation of particle transport, here the source of pollution spread is the channel network and permeable boundaries, which will be directly affected by pollution during periods of rainfall and especially floods. The concentration limit was given to the model in the form of variable figures based on discharge and precipitation in the range and equal to the primary stable threshold of the research subject (landfill). Based on the cumulative diagram of the outlet concentration from the permeable boundary and flow channel in the southeast region, the trend of changes in the cloud pollution concentration diagram, in the qualitative modeling of the plain, shows that in the forecast period, the increase in concentration will increase linearly. Considering that the waste disposal location is outside the plain, the rate of increase in pollution was not very high until the end of the initial simulation. However, the reason for the increase in concentration accumulation volume can be related to the existence of permeable boundaries and severe drop of underground water in this area. In other words, when the underground water level drops too much in the saturation area of the plain, the direction of the flow will move the volume of polluted water towards the aquifer at a higher speed.Conclusion: If the situation of groundwater withdrawals continues in the same way, in addition to the reduction of the groundwater storage of the plain, the quality of the remaining water storage will also decrease. This causes more serious problems in the agricultural situation of the region. The results of the implementation of quantitative and qualitative model in order to investigate the infiltration of polluted water from the landfill based on the concentration of pollution, showed that there is a high probability of the infiltration of polluted particles from the south wall side to the aquifer during periods of rainfall Event that current is run in the channels accidently. and then the expansion to the sea will actually occur due to the drop in the water level of the Caspian Sea. Water infiltration is more likely in the eastern regions than in the western regions. The reason for choosing the spread of pollution from the eastern waste disposal site in order to show the accumulation of polluted particles and the repulsion from the sea was the same. It is suggested that in the field of policy making, in order to control the plain's leachate crisis, appropriate bed construction and walling of the waste accumulation area should be applied based on the flow direction. Manuscript profile -
Open Access Article
20 - Investigation of Thin Layer-Drying Kinetics of Strawberry Using Infrared Radiation
F. Salehi Introduction: One of the new techniques in the drying of food is the application of infrared radiation that increases the drying rate, enhanced the final product quality, and decreases the costs of the process. Materials and Methods: In this study, drying kinet More Introduction: One of the new techniques in the drying of food is the application of infrared radiation that increases the drying rate, enhanced the final product quality, and decreases the costs of the process. Materials and Methods: In this study, drying kinetic modeling of strawberry in an infrared dryer was investigated. The effect of radiation lamp power (150, 250 and 375 W) and distance of the lamp from the sample (5, 7.5 and 10 cm), on drying time, and moisture diffusion coefficients during the drying process of strawberry were evaluated. For measuring the weight of the samples during experimentation without taking them out of the dryer, the tray with samples was suspended on the digital balance. Standard models (Wang and Singh, Henderson and Pabis, Approximation of diffusion, Page, Modified Page –II, Newton, Midilli and Logarithmic) were fitted to experimental data to study the drying kinetics and fitting quality (coefficient of determination and standard error) of them was analyzed. Results: By increasing infrared lamp power from 150 to 375 W, the drying time of strawberry is reduced by 79.8%. Decreasing the distance of the lamp from a sample from 10 to 5 cm, 40.1 % of drying time is reduced. The effective diffusivity coefficient was increased by increasing heat source power and decreasing distance. Moisture effective diffusivity coefficient of strawberry was between 1.54×10-9 to 13.83×10-9 m2/s. Conclusion: The effect of radiation lamp power and distance on the drying process of strawberry is significant. Modeling of strawberry drying process showed that all the models led to proper results, but in total, the Page model, compared to other studied models, with the biggest coefficient of determination (R2=0.999) and the smallest error (<0.011), had closer results to the experimental data. Manuscript profile -
Open Access Article
21 - Biosorption of Cu (II) by Dead Fungal biomass of Penicillium Camemberti: Batch and Fixed Bed studied
Rana Khalilnezhad Moayed Hosseini SadrBackground and Objectives: The presence of heavy metals in aqueous sources is one of the most important problems that effects on health and environment. Adsorption by microorganisms using methods has many advantages. For this purpose, used microorganisms such as fungi, MoreBackground and Objectives: The presence of heavy metals in aqueous sources is one of the most important problems that effects on health and environment. Adsorption by microorganisms using methods has many advantages. For this purpose, used microorganisms such as fungi, bacteria, and algae for removing heavy metals. Materials and methods: In this study the use of non-living fungal of Penicillium camemberti as biosorbent for removal of copper ions from aqueous solution was investigated in batch system and fixed bed column. In the batch system, for the biological absorption of copper, the parameters of temperature, pH, the dosage of biosorbent and contact time were optimized. In the kinetic study of the biosorption of copper metal by means of the non-living fungus, the Lagergren intraparticle diffusion models have been used. Findings: Considering the obtained results, it is determined that the biological absorption of copper using fungus follows from the second order equation because in the second order state, the amounts of qcal are close to the amounts of qexp and also R2>0/97.The results also demonstrate that an intra-particle diffusion mechanism play a significant role in the sorption process. In continues system, the biosorbent was turned into granul and the effects of hight and flow rate studied. The structure of Penicillium camemberti was characterized by IR spectrometer. Disscusion and Conclusion: The results also demonstrate that adsorption mechanism plays a significant role in the sorption process. The maximum biosorption obtained from the batch process was 86/52% for biomass in pH=5/5. Manuscript profile -
Open Access Article
22 - Estimation the risk-neutral processes in jump–diffusion models of gold coin future contracts in Iran Mercantile Exchange
Nahid Malekiniya hosein asgari aloujEstimation the risk market prices and the functions of the stochastic processes of the model are necessary in commodity derivatives pricing. When a closed-form solution is unclear, estimating of the risk market price is a main question in the jump–diffusion models MoreEstimation the risk market prices and the functions of the stochastic processes of the model are necessary in commodity derivatives pricing. When a closed-form solution is unclear, estimating of the risk market price is a main question in the jump–diffusion models. This paper along with Gomez's, Habibilashgari's and Rodriguez's review (2016) is suggested to estimate the functions of the risk-neutral processes directly from market data of Iran. In this approach, there is no need to estimate the physical drift and the risk market prices of coin future contracts pricing. This research estimates the risk-neutral drifts, volatilities and parameters of the jump range distributions with Iran Mercantile Exchange data of the coin future contract , from 2010 to 2017. The findings show that JDM and DM under price the futures prices and the prices obtained with the JDM are closer to the observed prices than those obtained with the DM. For the longest maturities the JDM provides smaller errors than the DM. The higher the maturity, the higher the differences between the two models. Manuscript profile -
Open Access Article
23 - Option Hedging in Jump-Diffusion Markets by Malliavin Calculus
Minoo Bakhsh Mohammadlou Rahman FarnooshWe obtain the hedging strategy in a jump-diffusion market by minimizing the variance of the residual risk. We calculate the residual risk by two formulas: the Ito's formula and the jump-diffusion version of the Clark-Ocone formula. The results show that Malliavin calcul MoreWe obtain the hedging strategy in a jump-diffusion market by minimizing the variance of the residual risk. We calculate the residual risk by two formulas: the Ito's formula and the jump-diffusion version of the Clark-Ocone formula. The results show that Malliavin calculus can generate the hedging strategy under weaker assumptions. Thus afterward we do not require to check the strong condition on and the condition with bounded derivative is sufficient. Manuscript profile -
Open Access Article
24 - MDH Flow Past a Vertical Rotating Plate with Chemical Reaction and Mass Diffusion in the Presence of Hall Current
Neetu Kanaujia‎ U S Rajput -
Open Access Article
25 - The Study of the Diffusion Coefficient of Meso-Scale Eddies in the Persian Gulf
Amin Raeisi Hesameddin Mehrfar AbbasAli AliAkbariBidokhtiBackground and objectives: Meso-scale eddies are not only dynamically important, but also climatologically, environmentally, as well as in terms of air-sea interaction are of special importance. Due to the existence of oil and gas fields, the Persian Gulf is exposed to MoreBackground and objectives: Meso-scale eddies are not only dynamically important, but also climatologically, environmentally, as well as in terms of air-sea interaction are of special importance. Due to the existence of oil and gas fields, the Persian Gulf is exposed to oil pollution, analyzing the role of factors such as meso-scale eddies in the spread of pollution in the Persian Gulf is very important.Methods: In this study, sea level data related to the analyzed Aviso reference data series (2010-2014) were used and meso-scale eddies were identified and tracked using a method based on sea level, and the relevant maps were drawn. This method is more effective than other common methods of tracking eddies.Findings: By studying the location of formation of eddies, eddy distribution coefficient was also calculated and the results indicated that eddies created in spring have a larger scale and higher speed, while eddies created in winter have a smaller scale and lower speed.Discussion and Conclusion: The eddies located in the north and south of the Persian Gulf have moved to the west and east of the Persian Gulf, respectively, which is consistent with the results of other studies. The range of the most eddy activity in the entrance parts of the Persian Gulf is from the Strait of Hormuz and inclined to the coast of Iran as well as northwest of the Persian Gulf. The maximum number of eddies is observed in summer and winter and the least number of eddies is observed in spring and autumn. Manuscript profile -
Open Access Article
26 - Antibiotic Resistance Pattern of Klebsiella Pneumoniae from Patients in Qaem Teaching Hospital, Mashhad University of Medical Sciences
Ali Shamsazar Arshid Yousefi-Avarvand Farzad KhademiKlebsiella pneumoniae is a gram-negative, non-motile and capsular gram-negative bacillus. It is one of the most important human pathogens and is an important factor in causing nosocomial infections. The bacterium is inherently resistant to a number of antimicrobial agen MoreKlebsiella pneumoniae is a gram-negative, non-motile and capsular gram-negative bacillus. It is one of the most important human pathogens and is an important factor in causing nosocomial infections. The bacterium is inherently resistant to a number of antimicrobial agents. The aim of this study was to evaluate the antibiotic resistance pattern of Klebsiella pneumoniae isolated from patients referred to Ghaem hospital in Mashhad. A total of 274 Klebsiella pneumoniae isolates were collected from April to October 2013 from Qaem teaching hospital of Mashhad University of Medical Sciences. Identification of these isolates was performed using microbiological methods such as hot staining and differential media. Modified disk diffusion method (MDDM) was used to determine the susceptibility of bacteria to the antibiotics amoxicillin, nalidixic acid, cefotaxime, ceftizoxime, ceftriaxone, ceftazidime, ciprofloxazine, imipenem, and nitrofurantoin. In this study 175 isolates (87.63%) were from urine sample and 99 isolates (13.36%) were from different samples (blood, cerebrospinal fluid, ulcer, ascites, and secretions). Resistance of Klebsiella pneumoniae isolates to ciprofloxacin, imipenem, nitrofurantoin and gentamicin antibiotics were 71.46%, 9.56%, 3.39% and 30%, respectively. The results of this study indicate that resistance of Klebsiella pneumoniae isolates to different antibiotics is higher than previous studies. Further studies in this area could help guide us to better understand the antibiotic resistance of these infectious bacteria. Manuscript profile -
Open Access Article
27 - Antimicrobial Modified-Tragacanth Gum/Acrylic Acid Hydrogels for the Controlled Release of Quercetin
Javid Monjezi Rezvan Jamaledin -
Open Access Article
28 - An Investigation on the Modeling of Heat Distribution and Atomic Diffusion in the Joining of the AA2024-T4 to AA6061-T6 by TLP Process
Anbarzadeh A Sabet H Geranmayeh A. R -
Open Access Article
29 - A Comprehensive Review of Thermal Barrier Coatings Microstructure with Different Platinum-Modified Aluminide Bond Coats
A Rabieifar -
Open Access Article
30 - Green waste: A fresh approach to antimicrobial compounds
Ruchita Haldar Suresh Kumar Manukonda -
Open Access Article
31 - Fundamental Solution in the Theory of Thermoelastic Diffusion Materials with Double Porosity
T Kansal -
Open Access Article
32 - A Generalized Thermo-Elastic Diffusion Problem in a Functionally Graded Rotating Media Using Fractional Order Theory
K Paul B Mukhopadhyay -
Open Access Article
33 - Analysis of Reflection Phenomena in a Fiber Reinforced Piezo-Thermoelastic Half Space with Diffusion and Two-Temperature
K Jain S Kumar S Deswal -
Open Access Article
34 - Experimental and Numerical Investigation on Geometric Parameters of Aluminum Patches for Repairing Cracked Parts by Diffusion Method
S Dehghanpour A. R Nezamabadi M.M Attar F Barati M Tajdari -
Open Access Article
35 - Effect of Rotation and Stiffness on Surface Wave Propagation in a Elastic Layer Lying Over a Generalized Thermodiffusive Elastic Half-Space with Imperfect Boundary
R Kumar V Chawla -
Open Access Article
36 - Wave Propagation in Micropolar Thermoelastic Diffusion Medium
A Miglani S Kaushal -
Open Access Article
37 - Wave Propagation and Fundamental Solution of Initially Stressed Thermoelastic Diffusion with Voids
R Kumar R. Kumar -
Open Access Article
38 - Boundary Value Problems in Generalized Thermodiffusive Elastic Medium
K Sharma -
Open Access Article
39 - Three-dimensional Free Vibration Analysis of a Transversely Isotropic Thermoelastic Diffusive Cylindrical Panel
R Kumar T Kansal -
Open Access Article
40 - Problem of Rayleigh Wave Propagation in Thermoelastic Diffusion
R Kumar V Gupta -
Open Access Article
41 - A Second-Order Accurate Numerical Approximation for Two-Sided Fractional Boundary Value Advection-Diffusion Problem
Elyas Shivanian Hamid Reza Khodabandehlo -
Open Access Article
42 - ارائه روشی مبتنی بر رتبهبندی و الگوریتم انتشار گرما برای استخراج جامعه در شبکههای اجتماعی
Malihe Ebrahimi nejad Samaneh Hasan Zadeh Mehrdad Jalali -
Open Access Article
43 - Numerical Solution of Multidimensional Exponential Levy Equation by Block Pulse Function
Minoo Bakhshmohammadlou Rahman Farnoosh -
Open Access Article
44 - Oil Price estimating Under Dynamic Economic Models Using Markov Chain Monte Carlo Simulation Approach
Kianoush Fathi Vajargah Hossein Eslami Mofid Abadi Ebrahim Abbasi -
Open Access Article
45 - Explaining the state of medical science and medicine in the Islamic world of the Abbasid era (132-656 AH) and the ways of transferring it to the West (Europe)
Batool Rabiei Boshra Delrish Elham Malekzadeh Koorosh FathiAs it stands today, medical science did not grow and develop overnight. This science has been formed due to the efforts of millions of people throughout the history of mankind. Meanwhile, the fact is that one of the standard bearers of this sacred responsibility (medica MoreAs it stands today, medical science did not grow and develop overnight. This science has been formed due to the efforts of millions of people throughout the history of mankind. Meanwhile, the fact is that one of the standard bearers of this sacred responsibility (medical sciences) are Muslims. Muslims, during the Abbasid era, have developed this science more than any other civilization. Therefore, in this article, an attempt has been made to highlight the fact that the Renaissance of Europe is partly indebted to the inventions and discoveries of Islamic medicine of the Abbasid period, and the ways of transferring this science from the East to the West are documentedIn the upcoming research, in order to explain and analyze the progress of medical knowledge in the Abbasid era and the ways of its transfer to the West, the "diffusion theory" is used as the theoretical framework of the work. Based on this, the influential origin in the field of medical knowledge of the Islamic world in the Abbasid era is taken into account, and the influential destination is the Western civilization, and the ways and channels of transmission are mentioned along with its obstacles. The findings of the research show that medical knowledge was one of the first sciences that the Islamic world learned based on the medical data of Iran, India and Greece, and then developed it in the best possible way and spread it to other societies. Manuscript profile -
Open Access Article
46 - Studying the Antifungal effect of Hydroalcoholic extracts of three species of Medicinal plants from the growing areas of Meshgin Shahr against Clinical isolates of Candida Albicans.
Hojjat Eghbal Mehdi Ahmadi Sabegh Neda Jahani Yousef Jahani JelodarMethod: dual mixture of Pune-Peppermint extract, Pune-Sourberry, Sour-Peppermint and Triple Blend of Hydroalcoholic extract of Pune, Peppermint and Sorghum used. The extracts were diluted with propylene glycol and in addition to pure extracts, concentrations of 10, 20, MoreMethod: dual mixture of Pune-Peppermint extract, Pune-Sourberry, Sour-Peppermint and Triple Blend of Hydroalcoholic extract of Pune, Peppermint and Sorghum used. The extracts were diluted with propylene glycol and in addition to pure extracts, concentrations of 10, 20, 30, 40 and 50 mg / ml of extract were prepared. To study the effect of hydroalcoholic extracts of Pune, Mint and Sour and Dual Blend Triticale extracts of these three plants were used to grow Albicans candidate by antibiotic and MIC methodsResults: The results of this study showed that the triple mixture of Puneh, Mint and Savange extracts with a concentration of 50 mg / ml with a diameter of 32.2 mm had the highest diameter of the inhibition zone and the hydroalcoholic extract Peppermint at a concentration of 10 mg per milliliter with a diameter of 7 mm halo assigns the lowest diameter of the non-growth zone of Candida albicans. Also, the triple mixture of Puneh, Mint and Souri showed relatively similar results to fluconazole antibiotics.Conclusion: The results of the minimum inhibitory concentration showed that the lowest inhibitory concentration was related to the antibiotic fluconazole and the triple mixture of hydroalcoholic extract of Punea, Mint and Sardinia, and the lowest was the hydroalcoholic extract of Mint herb. Manuscript profile -
Open Access Article
47 - Study of kinetic and changes in the diffusion coefficient of the release of doxorubicin-Chrysin drugs coated with magnetic nanoparticles and polycaprolactone-polyethylene glycol copolymers
Sahar Jahangiri Leila Amirkhani Abolfazl Akbarzadeh Reza HajimohammadiIn recent years, the development of nanoparticles in the field of drug release has received much attention. This research aims to develop new methods for the physical modification of Fe3O4 superparamagnetic nanoparticles with polymers through physical retention. In this MoreIn recent years, the development of nanoparticles in the field of drug release has received much attention. This research aims to develop new methods for the physical modification of Fe3O4 superparamagnetic nanoparticles with polymers through physical retention. In this study, after synthesizing the biodegradable polycaprolactone-polyethylene glycol magnetic copolymer, the anticancer drugs doxorubicin and Chrysin in these polymers were encapsulated by dual emulsion (w / o / w). The effect of temperature and pH on drug release was investigated. After performing kinetic studies, the diffusion coefficient of drug release was also studied. The drug distribution was considered uniform and the system was assumed to be in Cartesian coordinates. The results showed that the diffusion coefficient of drug release followed Fick's law. At first, due to the high concentration difference of drugs in the early times, the diffusion coefficient was higher, but then with time and with decreasing the concentration difference, the diffusion coefficient decreased and remained constant. Manuscript profile -
Open Access Article
48 - Determining COVID-19 Tweet Check-Worthiness: Based On Deep Learning Approach
hosniyeh safiarian Mohammad Jafar Tarokh MohammadAli Afshar Kazemi -
Open Access Article
49 - A Knowledge Management Approach to Discovering Influential Users in Social Media
Hosniyeh Safi Arian Mohammad Jafar Tarokh -
Open Access Article
50 - Discovering influential content for improving knowledge management based on deep learning
Husnyeh Safearyan Mohammad Jafar Tarokh Mohammad ali afshar kazemiThe presence of social media has brought about fundamental changes in today's societies. These media are a good platform for users to share ideas. This has caused users to encounter a lot of information that is not suitable for them most of the time and has little influ MoreThe presence of social media has brought about fundamental changes in today's societies. These media are a good platform for users to share ideas. This has caused users to encounter a lot of information that is not suitable for them most of the time and has little influence on them. Providing a way to select effective posts for the user among a multitude of posts can be very important. The methods presented in recent research for selecting effective posts are based on statistical features related to various microblog data and less in terms of content content, each post has been measured on a specific user. Despite the variety of topics, content of tweets and different users, most of these methods are not accurate by providing a general model based on a large number of features and are not able to provide online predictions. In this study, by analyzing the dissemination of posts among users in a specific period of time, a method for measuring users' attention to shared content and their effects is examined. This method is named IKS, which is based on the characteristics of content published by The user is presented as a binary classroom problem based on in-depth learning. Evaluation of this method has been done using intuitive method and data set evaluation which is more accurate compared to other methods. Manuscript profile -
Open Access Article
51 - Knowledge Diffusion to Workplace Safety and Health Improvement
Kassu Jilcha Daniel Kitaw Birhanu Beshah -
Open Access Article
52 - بررسی متغیرهای چالشبرانگیز اجتماعیفرهنگی تأثیرگزار بر هویت زبانآموزان ایرانی
هاجر مقدسی حاجی آباد شعله کلاهی بهدخت مالامیریپژوهش حاضر متغیرهای فرهنگی اجتماعی چالش برانگیز و تاثیرگذار بر هویت زبان آموزان زبان انگلیسی در ایران را بررسی کرده است. برای دستیابی به متغیرها و حوزه های فرهنگی اجتماعی مشخص، مرور جامعی بر پیشینهی تحقیق بر مبنای دیدگاه مدرسان زبان انگلیسی و تحلیل کتب آموزشی زبان انگ Moreپژوهش حاضر متغیرهای فرهنگی اجتماعی چالش برانگیز و تاثیرگذار بر هویت زبان آموزان زبان انگلیسی در ایران را بررسی کرده است. برای دستیابی به متغیرها و حوزه های فرهنگی اجتماعی مشخص، مرور جامعی بر پیشینهی تحقیق بر مبنای دیدگاه مدرسان زبان انگلیسی و تحلیل کتب آموزشی زبان انگلیسی صورت گرفته است. علاوه بر آن، یک پرسشنامهی باز طراحی و بین پنجاه زبان آموز دختر و پسر ایرانی در گروه سنی سیزده تا بیست و یک سال (میانگین سنی 16) که بر اساس نظریه اریکسون در مرحله سردرگمی هویتی قرار دارند جهت بررسی متغیرهای جدید احتمالی توزیع گردید. در نتیجه، فهرستی از عوامل تاثیر گذار بدست آمد که متغیرهای فرهنگی اجتماعی تاثیرگذار بر زبان آموزان ایرانی را با جزییات مشخص میکند و زمینه را برای تحقیقات بعدی مهیا میسازد. فهرست جامعی از متغیرهای فرهنگی اجتماعی تاثیرگذار بدست آمد که می تواند در پژوهشهای بین رشته ای مربوط به آموزش زبان انگلیسی، جامه شناسی زبان، مطالعات فرهنگی و غیره کارایی داشته باشد. نتایج تحقیق همچنین ضرورت آگاهی از عوامل فرهنگی اجتماعی تاثیرگذار بر هویت زبان آموزان ایرانی را در کلاس های درس و دوره های تربیت معلم روشن میکند. Manuscript profile -
Open Access Article
53 - Antagonistic effect of native lactic acid bacteria against foodborne bacterial pathogens
A. Tarinejad P. Pourabdi Sarabi M. A. HejaziIdentification of lactic acid bacteria, bacteriocin producing has been noticeable by most researchers. The surveys showed that bacteriocins of lactic acid bacteria has antibacterial effect against bacteria of poisoning agent, so these bacteriocins could be used as natur MoreIdentification of lactic acid bacteria, bacteriocin producing has been noticeable by most researchers. The surveys showed that bacteriocins of lactic acid bacteria has antibacterial effect against bacteria of poisoning agent, so these bacteriocins could be used as natural preserving of food materials. In this research, antimicrobial activities of bacterial supernatant from 10 native strain of lactic acid bacteria existing in Biotechnology Research Institute of Iran (ABRII), Branch of North-West and West Region of Iran evaluated by disk diffusion assay against seven pathogen including Listeria innocua, Bacillus cereus, flexneri Shigella, Escherichia coli, Staphylococcus aureus, Yersinia entrocolitica, Klebsiella pneumonia. Each test had three replications and the inhibition zone diameter measured in strains and compared with each other. At next step, peptide identification of antibacterial agent was detected by trypsin enzyme treatment. The results represented that lactic acid strains represented good antimicrobial potential against seven bacteria of poisoning agent. Also 15E strain with 6.03mm and 0.167mm inhibition zone diameter versus flexneri shigella and Yersinia entrocolitica showed the highest and lowest rate of suppression, respectively. Escherichia coli and Shigella flexneri the sensitive and Bacillus cereus as resistant strain was detected against bacteriocins of lactic acid bacteria. Also enzyme treatment result confirm peptide identification of antibacterial agent. T2 native strain could consider as strain with high potential versus gram-negative bacteria like Flexneri shigella, E. coli, Yersinia entrocolitica, and Klebsiella pneumonia. Manuscript profile -
Open Access Article
54 - Antibacterial effects of castor oil on foodborne pathogens: comparative evaluation of the components
samaneh hatami masud Yavarmanesh, M. Ali Hatami, S.For centuries, antimicrobial compounds derived from plants, have been used for medicinal treatment. The aim of this study was to evaluate the antibacterial activity of castor seed oil extracted from Mashhad and Isfahan varieties on Staphylococcus aureus, Escherichia col MoreFor centuries, antimicrobial compounds derived from plants, have been used for medicinal treatment. The aim of this study was to evaluate the antibacterial activity of castor seed oil extracted from Mashhad and Isfahan varieties on Staphylococcus aureus, Escherichia coli and Listeria inocula. The sensitivity of the indicator bacteria was evaluated using disc diffusion technique and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were tested by broth micro-dilution assays. Oil from castor seeds was extract by Soxhlet method and the extracted oils were analyzed by a gas chromatograph connected to a mass spectrometer (GC/MS). According to the results of various dilutions of the extracts, MIC for castor oils ranged 12.5-25%, except for the Isfahan variety that was estimated at 6.25-12.5% for E. coli. The two varieties of castor oils showed the MBC activity on the indicator organisms at the original (100%) concentration. Based on GC/MS data, ricinoleic acid (1.307%), genetistic acid (0.597%) and palmitic acid (1.947%) were detected in oil extracted from Isfahan variety; meanwhile these compounds did not found in Mashhad variety. According to the results, the two castor varieties had antibacterial impact on E. coli. In addition, the overall antimicrobial activity of Isfahan variety was higher than Mashhad type. It seems that the presence of phenolic compounds as well as camphoric and unsaturated fatty acids is the major reason for the higher antibacterial effect of Isfahan variety on E. coli. Considering the inhibitory impact of castor oil, it can be used as a natural preservative in food industry. Manuscript profile -
Open Access Article
55 - The study of antibacterial activity of non-polar extract of Malva silvestris L., using well diffusion and tube dilution method.
akbar hassanpour solmaz zakhireh amirreza ebadi Nowadays, due to the resistance of bacteria to antibiotics and their side effects, much attention is paid to the antibacterial properties of medicinal plants. Malva sylvestis L. plays an important role in traditional medicine and herbal medicine industry. T More Nowadays, due to the resistance of bacteria to antibiotics and their side effects, much attention is paid to the antibacterial properties of medicinal plants. Malva sylvestis L. plays an important role in traditional medicine and herbal medicine industry. This study deals with antibacterial effects of 50, 100, 200, 400 mg/ml concentration of non-polar extract of Malva sylvestris L. on Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa bacteria by means of well diffusion method. Determination test of MIC (Minimum inhibitory concentration of bacteria growth) and MBC (Minimum bactericidal concentration) was done by tube dilution method. The results indicated that non-polar extract of Malva sylvestris L. inhibits growth of Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa bacteria. The inhibitory effect increases by increasing the extract concentration. MIC and MBC of these bacteria respectively varies from 12.5-50 mg/ml and 12.5-100 mg/ml respectively. This extract can be a good candidate for future in vivo studies for production of new antibacterial drugs. Manuscript profile -
Open Access Article
56 - Dynamic light scattering: A useful technique to characterize nanoparticles
Abbas Rahdar Nooshin Amini Faezeh Askari Md. Susan -
Open Access Article
57 - Studding Democracy Convergence in Developing Countries: A Spatial Econometric Approach
Seyed Kamal Sadeghi mohsen pourabdollahan Parviz Mohamadzadeh zahra karimi parvin alimoradi afsharThe purpose of this paper is to study empirically the convergence of democracy in developing countries. For this purpose, the spatial econometric and panel data approach was used during the period 1990- 2014. The results show that the geographic proximity of countries h MoreThe purpose of this paper is to study empirically the convergence of democracy in developing countries. For this purpose, the spatial econometric and panel data approach was used during the period 1990- 2014. The results show that the geographic proximity of countries has a positive and significant effect on democracy. In other words, on average, the increase in the level of democracy in the geographic neighbors has led to a 6 percent increase in democracy, which reflects the political influence of each other. Also, foreign aids does not have a significant effect on the spread of democracy in developing countries. In general, the spatial effects of democracy or the theory of diffusion in developing countries are confirmed. Therefore, According to the theory of diffusion and convergence of democracy, increase or decrease in democracy in a country can increase or decrease democracy in neighboring countries. Manuscript profile -
Open Access Article
58 - Designing a New Gate-Diffusion Input in Quantum-Dot Cellular Automata Technology
Hamidreza Sadrarhamii Sayed Mohammadali Zanjani Mehdi Dolatshahi Behrang BarekatainQuantum-dot cellular automata (QCA) is a modern technology, which has higher speed, lower power consumption, higher density, and lower complexity than conventional technologies, such as CMOS. Moreover, the gate diffusion input (GDI) technique has been successful in redu MoreQuantum-dot cellular automata (QCA) is a modern technology, which has higher speed, lower power consumption, higher density, and lower complexity than conventional technologies, such as CMOS. Moreover, the gate diffusion input (GDI) technique has been successful in reducing complexity, area, and energy consumption in low-power circuit designs. In this technique, a wide range of complex logic functions can be implemented using only two transistors as the main block. In this study, a QCA-based GDI block is proposed using only 11 cells as a standard design unit that can be used to implement basic functions such as AND, OR, MUX, BUFFER, NOT and XOR in digital circuits. QCADesigner simulations of the functions in 18 nm technology indicate the superior performance of the proposed block with only one clock cycle delay in performing the operations. Moreover, the power consumption analysis of the designed circuits is performed using QCADesigner. The advantages of the proposed circuit compared to previous designs are 31% reduction in cell count, 50% smaller surface area, and 17% reduction in total energy loss. Manuscript profile -
Open Access Article
59 - Antimicrobial effect of walnut leaves aqueous extract and comparison of disc diffusion and wells methods
Afshin alimohammadi Afshin Javadi Elham YaghmaToday food safety is a public health issue. One of the methods of healthy food production is the use of natural materials. The use of essential oils and plant extracts as antibacterial and antifungal additives is one of these methods. Antimicrobial compositions obtained MoreToday food safety is a public health issue. One of the methods of healthy food production is the use of natural materials. The use of essential oils and plant extracts as antibacterial and antifungal additives is one of these methods. Antimicrobial compositions obtained from plants were removed by different mechanisms of antibiotics, in which the effective influences of walnut and its components are significant. The aim of this study was to evaluate the antimicrobial effect of walnut leaf extract on Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), determine the optimal amount of extract and sensitivity to each of the bacteria against the extract and determine the most sensitive method of the study. In this study, the leaves was extracted from the walnut and then the antimicrobial properties of the extract and its optimal concentrations were measured using disc and well methods on S. aureus and E. coli. Based on the results, the extract of walnut leaves in the concentrations of 12.5% up to the above has antimicrobial effect. By increasing the amount of extract, the growth rate of the bacteria significantly decreases (p<0.01). The highest non-growth halo in both methods was obtained from the control sample containing chloramphenicol disk on the E. coli (24 mm) and after it, the sample that contain 50% extract on S. aureus had 13.33 non-growth halo in the well method, and in the disc method, the 50% extract of S. aureus had the highest non-growth halo (11 mm). In fact, S. aureus was more susceptible to walnut leaves extract than E. coli in both methods. However, between the two methods, the sensitivity of the wells samples was more than the discontinuation method. The overall result shows that the sample containing 50% walnut leaf extract on S. aureus has the most antimicrobial activity among other samples after the control sample (chloramphenicol disc on E. coli). Manuscript profile -
Open Access Article
60 - Evaluation of antimicrobial activity of Lactobacilli isolated from traditional sourdoughs against Bacillus cereus
Abolfazl Golshan Tafti Ghazal Yazdanpanah Mohammad Hassan FooladiIn this study, the inhibitory effect of 71 Lactobacilli isolated from traditional sourdoughs against Bacillus cereus was evaluated and compared by using three methods (spot on lawn,well diffusion and disk diffusion). There was no inhibition zone around the discs and wel MoreIn this study, the inhibitory effect of 71 Lactobacilli isolated from traditional sourdoughs against Bacillus cereus was evaluated and compared by using three methods (spot on lawn,well diffusion and disk diffusion). There was no inhibition zone around the discs and wells in the well diffusion and disk diffusion methods. The inhibitory effect of Lactobacillus isolates against Bacillus cereus in the Spot on lawn method was observed as a clear zone around the colonies. All Lactobacillus isolates were able to inhibit the growth of Bacillus cereus in the spot on lawn method, but there was a significant difference (p<0.01) among the isolates in terms of antimicrobial activity. Among the Lactobacillus isolates, 8 isolates had significantly stronger antimicrobial activity and the diameter of clear zone around the colonies was reported in the range of 2.67-7.83 mm. The diameter of clear zone around the Lactobacillusisolates 70, 46, 21, 55, 59 and 11 was 7.83, 7.67, 7.33, 7.16, 7 and 7 mm, respectively. Therefore, they were reported as Lactobacillus isolates with strong antimicrobial activity in the spot on lawn method. These isolates can have potential to be used as starter cultures in production of sourdough and bread. Manuscript profile -
Open Access Article
61 - Antimicrobial activity of aqueous, alcoholic and buffer extracts of honey-bee propolis on oral-intestinal bacteria
Mahnoush Aboutorab Mohammad Goli Elham KhosraviPropolis plays an antibacterial, anti-fungal, anti-parasitic, antioxidant, anti-inflammatory, anti-caries role due to its plant-derived compounds such as polyphenols and proteins such as 10-HDA. It has long been a therapeutic role for diseases, especially infections. In MorePropolis plays an antibacterial, anti-fungal, anti-parasitic, antioxidant, anti-inflammatory, anti-caries role due to its plant-derived compounds such as polyphenols and proteins such as 10-HDA. It has long been a therapeutic role for diseases, especially infections. In this study antimicrobial activity of alcoholic, aqueous and buffer extract of propolis, on oral bacteria including Streptococcus mutans, Streptococcus epidermidis, Staphylococcus aureus, and gastro-intestinal bacteria including Streptococcus salivarius and Escherichia coli measured using micro broth dilution test for assessing of minimum inhibitory concentration (MIC) and disk diffusion test for assessing of diameter of inhibition zone. The MIC did not differ significantly between the three alcoholic, aqueous and buffer extracts, i.e., the effect of the solvents on the solubility of the antibacterial compounds was approximately the same (P > 0.05). The most resistant gram-positive bacterium to alcoholic and buffer extract, Streptococcus mutans and the most resistant to all extracts, Escherichia coli, were reported. There was no significant difference between the bacterial resistance in the aqueous extract of propolis (P> 0.05). In the disk diffusion test, increasing the concentration of extracts had a significant effect on the bacterial killing rate and was identified as the most susceptible bacterium to the extracts Staphylococcus epidermidis and the most resistant bacterium Staphylococcus aureus. The bacteria were also more sensitive to buffer extract. Manuscript profile -
Open Access Article
62 - Introducing Pt/ZnO as a new non carbon substrate electro catalyst for oxygen reduction reaction at low temperature acidic fuel cells
Rasol Abdullah Mirzaie Fatemeh Hamedi -
Open Access Article
63 - The Explanation of Decision Making Process in Establishing Of the Entrepreneurship in Rural Areas, With Emphasis on Gender Approach (Case Study: Souleghan District)
Fazileh Dadvarkhani Somayeh MosaviThe aim of this empirical research is to analyze the factors influencing women's decision- making regarding adopting the entrepreneurship. In another word it evaluates the main factors which are effecting on extension of innovation adoption finalizing the adoption of en MoreThe aim of this empirical research is to analyze the factors influencing women's decision- making regarding adopting the entrepreneurship. In another word it evaluates the main factors which are effecting on extension of innovation adoption finalizing the adoption of entrepreneurship between rural women. The research concentrated on research in villages such as of Kan district that have considerable amount of entrepreneurs. The data has been collected by questionnaire on the base of Likert model and the documentary method as well, interviews . All entrepreneurs' women in the research area have been chosen, so no random selection is used. The statistical population of the research is the entrepreneurs family who growing and selling plants and flowers and living in 4 villages of the souleghan district.The research statistical population is 2,713 people, which include 667 households in the study area. All recipients of entrepreneurship and innovation that living in the 4 villages of Kan- souleghan are included in the sample population of the research ,that they are about 82 men and their wives.The data has been collected through the field work and library- base .they have been collected by questionnaires, interviews, books and various methods. The results shows that the family and social factors and personality of respondents have a greatest impact on the decision-making process of women in accepting an entrepreneurship, as well as their speed to make a decision. Finally, in the next step economic factors play a considerable role in this process and to their acceptance of an innovation. Manuscript profile -
Open Access Article
64 - شناسایی مواد موثره موجود در عصاره و اسانس گیاه زینتی-دارویی سداب (Ruta graveolens L) و بررسی اثر ضد میکروبی آنها
فاطمه ترابی داود هاشم آبادی بهزاد کاویانی لیلا اسدپوراین پژوهش با هدف بررسی مواد موثره موجود در عصاره و اسانس گیاه زینتی-دارویی سداب و بررسی اثر ضد میکروبی آنها انجام شد. بدینمنظور در آبان ماه 1398 اندام هوایی سداب از زیستگاه طبیعی آن در ارتفاعات چابکسر-استان گیلان جمعآوری شد. برگها و ساقه گیاه در آون الکتریکی با دمای Moreاین پژوهش با هدف بررسی مواد موثره موجود در عصاره و اسانس گیاه زینتی-دارویی سداب و بررسی اثر ضد میکروبی آنها انجام شد. بدینمنظور در آبان ماه 1398 اندام هوایی سداب از زیستگاه طبیعی آن در ارتفاعات چابکسر-استان گیلان جمعآوری شد. برگها و ساقه گیاه در آون الکتریکی با دمای 75 درجه سانتیگراد به مدت 24 ساعت خشک و سپس توسط کلونجر عصاره و اسانس گیاه استخراج شد. جهت شناسایی ترکیبات موثره عصاره و اسانس از GC-MS استفاده شد. نتایج نشان داد که Hexadecanoic acid، Isomaturnin، 2-Ethyl-1,3,4,5,6,7,8-heptamethy و12-methoxy-19-norpodocarpa بهترتیب بیشترین ترکیب موجود در اسانس برگ، اسانس ساقه، عصاره برگ و عصاره ساقه سداب است. نتایج تست میکروبی به روش دیسک دیفیوژن روی سویههای Pseudomonas aeruginosa, Staphylococcus aureus, Acinetobacter baumannii and Escherichia coli نشان داد که عصاره برگ و ساقه سداب بیشترین اثر را در برابر مهار باکتری A. baumannii دارد. بررسی نتایج MIC و MBC نشان داد که باکتری S. aureus با کمترین MIC و MBC حساسترین باکتری در برابر اسانس برگ و ساقه سداب است درحالیکه A. baumannii با کمترین MBC بیشترین حساسیت را به عصاره برگ سداب نشان داد. بنابراین میتوان از عصاره و اسانس گیاه سداب به-عنوان یک ماده ضد میکروبی علیه باکتریهای بیماریزای انسانی استفاده نمود. Manuscript profile -
Open Access Article
65 - The impact of open innovation on the empowerment of employees, the productivity of knowledge sharing Mellat Bank, Region 4)
mahnaz bagheri TanhaThe method of this research is based on the practical purpose and the nature of descriptive-survey data collection. The statistical population of this research includes the employees of Bank Mellat branches of District 4 in Tehran, whose number is 420. Using Morgan's ta MoreThe method of this research is based on the practical purpose and the nature of descriptive-survey data collection. The statistical population of this research includes the employees of Bank Mellat branches of District 4 in Tehran, whose number is 420. Using Morgan's table, a sample size equal to 201 people was selected for the study and the questionnaires were distributed among them by systematic random sampling method. To determine the reliability and validity of the questionnaire, the content validity method and the CVR index were used and it was found that the questionnaire has the required validity. Also, the obtained Cronbach's alpha coefficient showed that the reliability of the research measurement tool can be relied upon. Then, the collected data were analyzed using structural equation modeling method and AMOS software. The results of the data test showed that open innovation has a significant impact on empowering employees. Also, the dimensions of open innovation, which include the production and creation of open innovation, the dissemination and expansion of open innovation, and the use of open innovation through the mediating effect of knowledge sharing, have a significant impact on empowering employees. Only the dimension of maintaining and maintaining open innovation through the mediating effect of knowledge sharing does not have a significant effect on employee empowerment. Manuscript profile -
Open Access Article
66 - Predicting the Smartphone Addiction Based on Depression, Fear of Missing Out, and Identity Diffusion
Sadeq Fallah Shahram Alizade Nikzad Ghanbari Fatemeh Zamani The present study aimed to investigate the role of depression, identity diffusion, and fear of missing out in predicting smartphone addiction among adolescents in Tehran. The research was a cross-sectional correlational study. 382 high school students in Tehr More The present study aimed to investigate the role of depression, identity diffusion, and fear of missing out in predicting smartphone addiction among adolescents in Tehran. The research was a cross-sectional correlational study. 382 high school students in Tehran were selected using convenient sampling method and completed the short form of Smartphone Addiction Scale (Kwon, Kim, Cho & Yang, 2013), Fear of Missing Out Scale (Abel, Buff & Burr, 2016), Kutcher Adolescent Depression Scale (LeBlanc, Almudevar, Brooks &Kutcher, 2002) and Erikson Psychosocial stage Inventory (Rosenthal, Gurney & moore, 1981). The data were analyzed using Pearson correlation and stepwise multiple regression. The findings showed that all three predictor variables including depression, fear of missing out, and identity diffusion could significantly predict smartphone addiction among adolescents and account for 24 percent of the variance in smartphone addiction among adolescents. Based on these findings preventive programs can be designed not only to reduce depression, fear of missing out, and identity diffusion but also to reduce smartphone addiction among adolescents. Manuscript profile -
Open Access Article
67 - A Comparison study to determine glycopeptide resistance in Staphylococcus aureus isolates collected from Shohada Hospital during three years
shahrzad Ghasemi Saberi Haiedeh Mobaiyen Jeinus Bayat Makoo Sanam Sadeghi MohammadiBackground & Objectives: Glycopeptides such as vancomycin and ticoplanin are commonly used as antibiotic of choice for treatment of infections caused by methicillin-resistant Staphylococcus aureus. Following first reports of vancomycin resistant strains, the presenc MoreBackground & Objectives: Glycopeptides such as vancomycin and ticoplanin are commonly used as antibiotic of choice for treatment of infections caused by methicillin-resistant Staphylococcus aureus. Following first reports of vancomycin resistant strains, the presence and distribution of these bacteria have been continuously investigated in the clinic centers. This study was aimed to investigate the distribution of glycopeptide resistant S. aureus isolated from Shohada hospital during a period of three years. Materials & Methods: This cross-sectional study was carried out on 182 S. aureus strains isolated from wound orthopedic patients in three years. Resistance against glycopeptides, linezolid and ciprofloxacin were examined by disk agar diffusion method. Screening plate method containing 6µg / ml of vancomycin was used for resistance against vancomycin. Results: Among the 182 isolates, only 2 cases (1.09%) were confirmed as vancomycin-resistant S. aureus, VISA strains. In isolates from the last year of sampling, the resistance was controlled. Among total isolates, in 31 isolates (17%) demonstrated intermediate reaction against ticoplanin. Conclusion: Significant differences are indicated between glycopeptide resistances isolated from different years, despite a report of two VISA isolates in our center, which showed that the resistance controlled by the authorities. Manuscript profile -
Open Access Article
68 - On the Design of Extended State-Dependent Differential Riccati Equation Controller for Nonlinear Reaction-Advection-Diffusion Partial Differential Equation with Multiple Delays
Fariba Bouzari Liavoli Ahmad Fakharian Hamid KhaloozadehThis paper proposes a sub-optimal Extended State-Dependent Differential Riccati Equation (ESDDRE) controller for nonlinear Reaction-Advection-Diffusion (R-A-D) Partial Differential Equation (PDE) systems with multiple delays. A State-Dependent Riccati Equation (SDRE) is MoreThis paper proposes a sub-optimal Extended State-Dependent Differential Riccati Equation (ESDDRE) controller for nonlinear Reaction-Advection-Diffusion (R-A-D) Partial Differential Equation (PDE) systems with multiple delays. A State-Dependent Riccati Equation (SDRE) is a nonlinear version of Linear Quadratic Regulator (LQR) in optimal control and it is used to analyze nonlinear optimal control problems. Instead of the linearization or the Jacobin procedure, the ESDDRE technique applies a State-Dependent Coefficients (SDC) for parameterization to construct an Extended Pseudo-Linearization (EPL) representation. All of the multiple delays sections in this presentation can be located in the system matrices and input vectors. The control effort of ESDDRE method is derived based on the Hamiltonian equation and also cost function according to the PDE systems. In addition, the L_2 stability is guaranteed by Poincaré inequality and as well as Lyapunov function regarded on the ESDDRE control strategy for the closed-loop system. The simulation results for the nonlinear R-A-D partial differential equation with one and two constant delays indicate that the proposed ESDDRE controller technique is efficient. Manuscript profile -
Open Access Article
69 - On a modi cation of the Chebyshev collocation method for solving fractional diffiusion equation
Hosein jalebbonab Hojatollah Adibi -
Open Access Article
70 - Galerkin Method for the Numerical Solution of the Advection-Diffusion Equation by Using Exponential B-splines
Melis Zorsahin Gorgulu Idris Dag -
Open Access Article
71 - A New Implicit Finite Difference Method for Solving Time Fractional Diffusion Equation
elham afshari -
Open Access Article
72 - Option Pricing on Commodity Prices Using Jump Diffusion Models
Tesfahun Berhane Molalign Adam Eshetu Haile -
Open Access Article
73 - AN ANALYTICAL SOLUTION FOR DIFFUSION AND NONLINEAR UPTAKE OF OXYGEN IN THE RETINA
Deepti Seth -
Open Access Article
74 - In-vitro Antibacterial and Antifungal Screening of Newly Synthesized Trifluoromethylated N-Heterocyclic ketenimines and 1-aza butadiene Derivatives
Rosa Edris Ameri Bita Mohtat Eskandar Alipour Nahid Rahimifard Behrooz Mirza -
Open Access Article
75 - Evaluation of In-vitro Antimicrobial Activity of some Newly Synthe-sized2-amino-3-phenylsulfonyl-4-aryl-4H-benzo[h]chromens Derivatives
Farzaneh Manouchehri Bahareh Sadeghi Farhood Najafi Mohammad Hossein Mosslemin -
Open Access Article
76 - Investigating the Effect of Al Temper type on Microstructure and Mechanical properties of Al 6061/Mg AZ31 alloys Diffusion Bonded Joint
مجتبی جعفریان علیرضا خدابنده مرتضی جعفریانIn this study, the effect of Al alloy temper type on the microstructure and mechanical properties of Al 6061 (T6,O) and Mg AZ31 (O) were investigated. The interface of joints was investigated by optical microscope (OM) and Scanning Electron Microscope (SEM) equipped wit MoreIn this study, the effect of Al alloy temper type on the microstructure and mechanical properties of Al 6061 (T6,O) and Mg AZ31 (O) were investigated. The interface of joints was investigated by optical microscope (OM) and Scanning Electron Microscope (SEM) equipped with EDS and Linescane analysis. Mechanical properties of joints were measured by using a Vickers microhardness and shear strength tests. According to the results, in Al 6061-O/Mg AZ31 joint, less plastic deformation in the Mg alloy, further diffusion rate of Mg atoms in the Al alloy and the formation of diffusion region with the lowest amount of microhardness (140 HV) and the highest amount of shear strength (32 MPa) was occurred compared to Al 6061-T6/Mg AZ31 joint. Evaluation of fracture surfaces indicates the occurrence of the failure in brittle phase of Al3Mg2. Manuscript profile -
Open Access Article
77 - Synthesis of Molybdenum disulfide solid lubricant coating on steel using Thermal-diffusion method
mehdi akbarzadeh Morteza ZanrahimiMolybdenum disulfide (MoS2) is one of the most solid lubricants applied on surfaces under friction condition in different ways. In this study, MoS2 coatings was applied on 316 stainless steel using thermal diffusion method at various temperatures and times. Coatings pro MoreMolybdenum disulfide (MoS2) is one of the most solid lubricants applied on surfaces under friction condition in different ways. In this study, MoS2 coatings was applied on 316 stainless steel using thermal diffusion method at various temperatures and times. Coatings properties were investigated using SEM, EDX, XRD and FTIR, Hardness Tester and Roughness tester. The results indicated formation of a uniform layer on the surface that contains MoS2 and MoO3-X phases. Coatings have thickness of 20-50 µm and grain size of 400-1000 nm and hardness of 350- 550 HV. Also in this study, the kinetics of diffusion layer between substrate and coating has been investigated. the kinetics of diffusion layer between substrate and coating has been investigated. It was found that thickness of diffusion layer changes with time at constant temperature follow from parabolic equation.The thickness of diffusion layer changes with time at at constant temperature follow from parabolic equation. Manuscript profile -
Open Access Article
78 - Investigation of the effect of substrate on formation of chromium- and vanadium carbide coatings by thermal reactive diffusion
علی اکبر قادی حسن ثقفیان Mansour SoltaniehIn this research, the effect of substrate on the formation of chromium- and vanadium carbide coating was studied by thermal reactive diffusion. The substrate of H13 steel was coated in two kinds of metal and oxide bath with molar ratio of Cr/V=3 for 14 hour at 1000˚C. C MoreIn this research, the effect of substrate on the formation of chromium- and vanadium carbide coating was studied by thermal reactive diffusion. The substrate of H13 steel was coated in two kinds of metal and oxide bath with molar ratio of Cr/V=3 for 14 hour at 1000˚C. Carbide coatings including chromium carbide (Cr3C2, Cr7C3), vanadium carbide (V8C7) and the complex carbide phase of Cr2VC2 were formed on H13 steel. The thickness of the carbide coating was 8.5±0.5 µm and 6.5±0.5 µm, respectively in metal bath and oxide bath. The amount of vanadium- to chromium- rich regions in the carbide coating was less than the ratio of vanadium to chromium content in the metal bath. The results of coating in the present study was compared to the results of coating in a similar condition on Ck45 steel. The type of substrate had an important role on the coating thickness and the phase distribution of vanadium- and chromium- rich regions. However, the element distribution in the coating was not affected by the kind of substrate. Manuscript profile -
Open Access Article
79 - Efect of temperature on microstructure and intermetallic compound formation of Diffusion Bonded Mg/Al joints
Mohammad Ammar Mofid Mostafa Hajian Heidary Ehsan Loryaei Hatef ShakeriThe diffusion bonding of two dissimilar alloys Al 5083 and Mg AZ31 was carried out at 420,430.440 and 450 °C for bonding time of 60 min. In order to characterize the microstructure evolution in the joint zone, scanning electron microscopy (SEM), energy dispersive sp MoreThe diffusion bonding of two dissimilar alloys Al 5083 and Mg AZ31 was carried out at 420,430.440 and 450 °C for bonding time of 60 min. In order to characterize the microstructure evolution in the joint zone, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) were applied. The results show that joint formation is attributed to the solid-state diffusion of Mg and Al into Al 5083 and Mg AZ31 alloys followed by eutectic formation and constitutional liquation along the interface. At bonding temperature of 430°C diffusion induced grain coarsening was observed at the interface. With increase in bonding temperature, the atomic diffusivity increases, results in easier and speeder chemical bonding. In bonding temperature of 440°C the weld had an irregular shaped region in the weld center, having a different microstructure from the two base materials. The irregular shaped region contained a large volume of intermetallic compound Al12Mg17 and showed significantly higher hardness in the weld center. The present study suggests that constitutional liquation resulted in the intermetallic compound Al12Mg17 in the weld center. Manuscript profile -
Open Access Article
80 - Electrochemical study on hot corrosion behavior of aluminide diffusion coating deposited on inconel 713C superalloy
Esmaeil Taheri Mehdi VerdianIn this study, the hot corrosion resistance of diffusion aluminide coating on Inconel 713C was investigated using electrochemical techniques. In this regard, potentiodynamic polarization tests were performed at 750 °C in two kinds of molten salts. The former contain MoreIn this study, the hot corrosion resistance of diffusion aluminide coating on Inconel 713C was investigated using electrochemical techniques. In this regard, potentiodynamic polarization tests were performed at 750 °C in two kinds of molten salts. The former contained 70% sodium sulphate and 30% sodium chloride. The latter was composed of 70% sodium sulphate, 25% sodium chloride and 5% vanadium pentoxide. The phase composition and microstructure of coatings and corrosion products were investigated using XRD and SEM-EDS techniques. The results showed that in the presence of vanadium, the protection efficiency of coatings increased and a current-independent region was observed in anodic polarization curve. Here, a compact corrosion product layer was seen. In absence of vanadium, both coated and uncoated samples exhibited similar corrosion rates. However, in comparison to vanadium-containing environment, all samples showed lower corrosion rate. In this case, the coatings exhibited active anodic behavior. The corrosion products were porous and discontinuous in vanadium free environment. Manuscript profile -
Open Access Article
81 - Investigating of High Temperature Oxidation and Thermal Shock Properties of YSZ/Al2O3 Composite Thermal Barrier Coatings with Alumina Made by Solution Precursor Thermal Spray
Saeid Taghi-ramezani Zia Valefi Naser EhsaniIn this research, a double layer thermal barrier coating was applied and then an alumina diffusion barrier layer was deposited on the YSZ by two solution precersore plasma and solution precersore flame spraying. High temperature oxidation and thermal shock resistance te MoreIn this research, a double layer thermal barrier coating was applied and then an alumina diffusion barrier layer was deposited on the YSZ by two solution precersore plasma and solution precersore flame spraying. High temperature oxidation and thermal shock resistance tests were done at 1100˚C. Microstructure of coatings were studied by optical Microscopy and Field Emission Scanning Electron Microscopy. Comparison of the microstructures of coatings showed that applying of Alumina with the solution precursor flame spray process upgrades the thermal properties. High temperature oxidation and thermal shock resistance of YSZ/Al2O3 coatings with Alumina applied by the solution precersoure thermal spray with the same compound were studied. Findings showed that applying alumina with the solution precursor flame spray process leads to increase the amount of the deposited splats and proper contact between them, causes to decrease the diffusion of O2 and as a result TGO thickness decreases and also thermal shock resistance increases. Manuscript profile -
Open Access Article
82 - Comparison of Oxidation and Thermal Shock Properties of YSZ/Nanoal2o3 Composite Thermal Barrier Coatings Made By Plasma Spraying of Un-Pyrolyzed Precursor and Aglomerated Nanocrystalline Alumina Powder
Saeid Taghi-ramezani Zia Valefi Naser Ehsani masud mirjaniIn this research, firstly amorphous Alumina powder was produced by co-precipitation method. Then YSZ/Al2O3 coatings were applied by plasma spraying process in two types of pyrolyzed and crystalline nano-alumina. High temperature oxidation and thermal shock resistance te MoreIn this research, firstly amorphous Alumina powder was produced by co-precipitation method. Then YSZ/Al2O3 coatings were applied by plasma spraying process in two types of pyrolyzed and crystalline nano-alumina. High temperature oxidation and thermal shock resistance test were done at 1100˚C. Microstructure and phase analysis of coatings were studied by optical and electron microscopes and XRD method. Comparison of the microstructure of coatings showed that the use of crystalline nano-alumina powder in the YSZ/Alumina layer composite upgrades the thermal properties. High temperature oxidation and thermal shock resistance of plasma sprayed YSZ/Al2O3 with un-pyrolysed nano-alumina and coatings with same composition with crystalline nano-alumina to created by plasma spraying were studied. Findings showed that the use of un-pyrolyzed nano-alumina powder in YSZ/Al2O3 layer composite resulted in increased porosity and shrinkage cavities in the coating, which increased the diffusion of O2 that causes the TGO growth rate. Also, high density and proper contact between the splats made of crystalline nano-alumina powder results in higher resistance of thermal cycles. Manuscript profile -
Open Access Article
83 - Choosing the Right Approach to Public Policy-Making in Different Environments: A Meta-Synthesis Study
Nima Eskandarinia Karamollah Daneshfard Abolhasan FaghihiNowadays, public policy knowledge is faced with a host of new approaches including adaptive approaches, policy networking, closed innovation dissemination and open innovation dissemination. In such a situation, the ability to choose the right approach to policy-making f MoreNowadays, public policy knowledge is faced with a host of new approaches including adaptive approaches, policy networking, closed innovation dissemination and open innovation dissemination. In such a situation, the ability to choose the right approach to policy-making from a set of diverse approaches is very important. The purpose of this study is to provide a contingency framework for selecting the appropriate policy-making approach from the approaches of phased, adaptive, networking and dissemination of innovation under different environmental conditions. Using inductive qualitative theory-generating meta-synthesis method, theory is generated through the steps of data collection and sampling, intra-study and inter-study note-taking, and finally the establishment of dynamic relationships between variables. According to the findings of this study, in situations where predictive power is not present, the general policy cycle is useless. Under such circumstances, the power of forecasting should be increased first with the help of adaptive methods, and then the policy should be formulated with the help of one of the approaches of general policy cycle, open innovation, closed innovation or networking. The choice of each of these approaches also depends on the two variables of public participation and public innovation. Manuscript profile -
Open Access Article
84 - Explaining the Strategic model for management process of accepts, transfer and diffusion of new media technologies in Iranian audience perspective.
babak rahnavard kamran mohamadkhani aliakbar farhangi amirhosain mohamad davodiAt the present time acceleration technology advances and increased understanding of the strategic implications of technology, especially has been very important for media managers, today the duty of a converting of media technology into a competitive advantage. Technolo MoreAt the present time acceleration technology advances and increased understanding of the strategic implications of technology, especially has been very important for media managers, today the duty of a converting of media technology into a competitive advantage. Technology can be used as a target or final product. With the advent of digital convergence that is possible through a new form of media emerge and be forward-thinking media executives, as well as analyze the media environment and notice of the change process forward so that he will comply with the conditions of future policies and strategy, media plan. According to ICT infrastructure development and increase in Internet users in our country Iran, the audience interaction with modern media technology has a written policy requiring According to Iranian interests and audience desires strategy for adoption and transfer of modern media technologies be developed at the individual level In this paper the qualitative research approach, the impact of convergence on the characteristics of the audience, content and new media technologies survey and the extent and terms of admission, transfer and dissemination of new media technology from the perspective of media industry experts will introduce and finally strategic model from the impact of convergence on adoption of new media and technology transfer will be explained. Manuscript profile -
Open Access Article
85 - Strategic Analysis of Mobile Value Added Services (M-VAS) Market in Iran Using the System Dynamics Approach
Mohammad Ali Valafar naser hamidi mahmood alborzi Seyed Javad Iranban FardDespite the launch of mobile app markets in Iran, these markets have not been able to capture a significant market share under a highly competitive environment. Therefore, it is very important for industry managers to review and improve the acceptance process of these m MoreDespite the launch of mobile app markets in Iran, these markets have not been able to capture a significant market share under a highly competitive environment. Therefore, it is very important for industry managers to review and improve the acceptance process of these markets. After identifying the factors influencing the acceptance and attractiveness of marketplaces, this study examined the network effect by providing a dynamic model based on bass diffusion theory and modeled and simulated the studied market. This was done by presenting dynamic hypotheses, plotting causal loop diagram (CLD), stock-flow diagram (SFD), and entering mathematical equations in Vensim software. Then, after validating and ensuring the correctness of the model's performance, two different policies were implemented in the model. The research findings show that under the pressure of the Play Store, Iranian markets are still forced to improve their services and at the same time try to reduce the competitive distance with it. These marketplaces need to reconfigure their existing resources and core competencies, given the market dynamics and to gain emerging opportunities. Manuscript profile
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