Showing 24 results for Hosseinali
Volume 1, Issue 1 (3-2013)
Abstract
In this study, the effect of fructooligosaccharide as a prebiotic on the growth and density of lactobacillus in intestine of stellate (Acipenser stellatus) has been investigated. To do this, 90 individuals of stellate fingerlings (ten in each replications) were prepared with an average weight of 30.16 ± 0.14 gr from International Sturgeon Research Institute. This study was carried out in a completely randomized design with three replications in fiberglass tanks with 2000 liters volume. They were fed with feed containing 0, 1 and 2 percents of fructooligosaccharide (Raftilos P95, Sigma Company). Results indicated that feed with one percent fructooligosaccharide had a significant effect (P < 0.05) on weight gain, SGR, FCR, FE, PER and HI. The number of colonies regarding to lactobacillus showed a significant increase compared to the control (in one percent fructooligosaccharide). Results indicated that fructooligosaccharide as a prebiotic (in level of one percent in feed) caused good growth capabilities and feed efficiency through increasing the density of lactobacillus in intestine.
Volume 2, Issue 2 (Summer 2014)
Abstract
An important subject in the field of linguistics is the impact of one thought system on the community of lingual symbols. The relationship between mind and language conventions has long been of interest to linguists. The importance of this relationship becomes more prominent in comparative approaches where, through comparative study and analysis of the main schemas of the ideas of several thinkers or artists, the researcher traces the consistent and common use of linguistic symbols.
In the hermeneutic analysis of the works of Mowlana Jalal ad-Din Mohammad Rumi, the interpretation of symbols, analogy and codes governing his mind and language is a major research interest. One of the most important branches among these researches concerns the kinship of Mowlana’s language codes with other thinkers and artists.
On the other hand, Nietzsche, as a transcendental thinker, tries to use a symbolic language in explaining his thinking system. Due to his familiarity with the culture and literature of the East and the essential sameness of some of his principles with Mowlana’s transcendental approaches about the existence, morality, art , etc., Nietzsche achieves a set of symbols common with Rumi, which forms a shared language between the two thinkers.
Volume 3, Issue 2 (, (Articles in Persian) 2012)
Abstract
Intertextuality of two text: Comparative analysis between king Lear and Feridoon
Comparative study which has opened to investigation the text could illuminate the relationship between cultures and shows the originality and richness of one literature alongside with range of its stubbornness of our or other culture. Comparative analysis between Feridoon’s tragedy and King Lear shows the interlocking relationship and arrangement between two texts in different and completely dissimilar culture and different historical context with two kind of language.
Although mapping out the conscious or unconscious trace and impact of this texts over each other is completely impossible but the high level of intersexuality between the two texts is obvious so that this relationship could not be ignored. “similarity of plot”, “being tragically”, “impulses”, “familiarity of two text”, “dividing of kingdom”, “presence of destiny”, “parallel of characters”, “conflict”, “prediction”, “chorus” could be accepted as issues which are convinced common points between the two text. The analysis and survey toward understanding the equivalent between the two texts by helping of comparative literature is the fundamental question which has been followed by this paper.
Volume 3, Issue 2 (6-2014)
Abstract
Among the recently collected chalcidoid wasps in a rice field of eastern Guilan province (coast of Caspian Sea), in July 2012, there was a specimen of Pteromalidae belonging to the genus Callitula. It was identified as Callitula ferrierei (Bouček, 1964). Both genus and species are new record for Iranian fauna. Morphological characters and geographical distribution of the newly recorded species are given.
Volume 14, Issue 5 (8-2014)
Abstract
A two dimensional numerical study is presented for steady state performance analysis of a catalytic radiant counter-diffusive burner. In these burners, the gaseous fuel enters from the rear of the burner and passes through the insulation and catalyst layers. The oxygen enters the catalyst layer from the burner surface and opposite to the fuel path. The reaction takes place over the catalyst layer. In this paper, the momentum, energy and species conservation equations in porous and non-porous media are solved using the finite element method in the COMSOL software. The simulations are based on proposed corrections on boundary conditions and combustion rate of methane equation. The simulation results compared with experimental measurements published in the literature for the same geometry and conditions which shows a considerable (10%) improvements. It is shown that diffusion of oxygen through the pad limits the catalytic combustion and controls the fuel conversion in the burner.
Volume 14, Issue 9 (12-2014)
Abstract
In the present study, fabrication and performance testing of a flameless catalytic pad has been investigated. The catalyst was prepared with 1g of H2PtCl6.6H2O solved in 0.5 liter solvent contains 50% water and 50% ethanol and sprayed on the alumina - silica fiber mat as the catalyst support. The wet pad was dried and calcined before usage. The performance of the heater was evaluated by design and fabrication of a test stand which was capable of measuring parameters such as temperature at surface and in depth of the catalyst layer, the amount of pollutants such as CO and NOx, flow rate and pressure of the fuel and surface air circulation in front of the pad. In addition, by placing the panel containing the pad in an environmental test chamber, the effect of different climate conditions in five cities of Iran, i.e., Borojerd, Khalkhal, Lavan, Mahshahr and Puladshahr were investigated. Average surface temperature of the pad was measured about 350°C. No NOx was detected and CO emission of the burner was measured up to 5ppm. In Khalkhal conditions with the lowest temperature and humidity, the highest temperature at surface was recorded and the maximum CO emissions in Mahshahr with the highest temperature and humidity was about 3ppm. It was shown that increasing the fuel flow rate increases the surface temperature and CO emissions. It was also shown that an increase of environment temperature and humidity, increases the surface temperature.
Volume 14, Issue 10 (1-2015)
Abstract
In this paper, 5 samples of one kind of swirl injector with tangential inlets, which has been designed and manufactured by using CNC, have been tested. Above injector has a spray cone in the shape of very thin layer because it is formed an air core in injector center. In fact, this is a one-fluid injector but its operation is two-phase. In order to detect acceptable injector among them, characterization tests have been done in the propulsion laboratory of Tarbiat Modarres University for all sample injectors. The methods of experimental characterization have been described in detail in current paper and also important parameters introduced. In these tests, injection uniformity, symmetry, mass flow rate versus pressure difference and some other parameter such as spray cone angle are investigated. Experimental results have been compared with design points. Finally, one injector has been selected as a suitable and nearer to theoretical design injector among them. The selected injector can be used for validation of numerical analysis results and also doing some complemental microscopic experiments. The results show good agreement between theoretical predictions and experimental results.
Volume 16, Issue 13 (Conference Special Issue 2017)
Abstract
Volume 17, Issue 3 (5-2017)
Abstract
Prediction of spray droplet diameter distribution depends on the various parameters such as physical properties, fluid velocity, and discharge environment and injector geometry. The stage of forming droplets has a great variety in size and therefore will be predictable with a statistical approach. The maximum entropy principle is one of the most popular and best ways to predict the spray droplet size distribution along with the conservation equations. Due to some drawbacks in this model, the predicted results do not match well with the experimental data. It is suggested to improve the available energy source in the MEP model equation by numerical solution of flow inside the injector based on the CFD technique. This will enhance the calculation accuracy of the turbulent kinetic energy of the output spray. In fact, by using this sub-model in the maximum entropy model, the prediction accuracy of the spray characteristics is improved. Also, the requirement of the maximum entropy model to the experimental data as inputs has been reduced. By the present coupled model, the effect of spray upstream on the droplet size distribution can be considered with a good accuracy. The results show a close agreement with the available experimental data.
Volume 17, Issue 5 (7-2017)
Abstract
Gas turbine power and thermal efficiency increase with inlet temperature. Considering the temperature limitations for the alloys used in gas turbine components, employment of techniques for reduction of these components temperatures seems to be an essential subject. Based on the research conducted on this subject, among all the proposed methods, rib cooling yields higher heat transfer coefficient and among various types of ribs, V-shaped ribs have higher heat transfer compared to angled rib. The purpose of this feasibility study is to investigate the two proposed ribs for use in gas turbine from heat transfer and fluid flow view and compare their thermal performance. In this work, 3-D numerical simulation has been performed for V-shaped ribs with an angle of 〖60〗^° for the two cases of staggered and inline ribs in two opposite walls in a rectangular channel. Experimental results have been used for validation. The results indicate an enhancement of ~22% in heat transfer if V-shaped ribs with an angle 〖60〗^° and downstream orientation are located in staggering form in two opposite walls of a channel. In this case, an increase of 10% is observed for pressure drop, however, its thermal performance increases 12% which is positive and considerable.
Volume 18, Issue 1 (5-2014)
Abstract
Scheduling plays an important role in the development and success of the project; this has always been one of the main issues considered in operations and management science researches. Another reason for the focus of much research into it is the difficult nature of this problem. Therefore, special techniques and methods have been proposed to solve this problem. On the other hand, in order to intensify sanctions on foreign delaying projects, timely completion of projects has been accelerated. Therefore, attention to project robustness subject to project managements. In this article, a real issue is scheduled for a robust scheduling model of a refinery project. Since project scheduling has resource constraints such NP-Hard problems, simulated annealing algorithm was proposed to solve this problem. In order to validate the model, 4 problems with small size were chosen and the solutions obtained by the proposed algorithms were compared with the exact solution obtained by Lingo8 software. The results showed that the proposed algorithm is efficient and convergent to the optimal solution.
Volume 18, Issue 1 (3-2018)
Abstract
In this paper, the instability of wave motion on the surface of liquid sheet emanating from a swirl injector exposed to inner and outer air streams, before the breakup is considered using the linear instability analysis by a perturbation method. The forces acting on a liquid gas interface in sprays, including surface tension, pressure, inertia force, centrifugal force and viscous force, lead to grow the disturbances originated from inside the injector on the outgoing liquid sheet. Interaction between these forces ultimately breaks up the jet into the ligaments. The linear instability analysis used in the present study is different from prior analysis. A cylindrical liquid sheet has been considered in previous studies but the present study implements the linear instability on a conical annular liquid sheet. Due to the complexity of derived governing equations a semi-analytical and numerical method was utilized in the solution procedure. The present model is capable to solve governing equations for the liquid jet with large range of spray angle. The predicted results compared with the prior studies results and experiments. The results of the current model in comparison with prior models have better accordance with experimental data. Also, the results show that the improved linear theory (the present model) predicts the breakup length better than linear theory.
Volume 18, Issue 2 (4-2018)
Abstract
In this paper, the goal is to provide analytical solutions for the thin film flow of a non-Newtonian fluid in different geometries and boundary conditions. An analytical solution for the non-Newtonian fluids is one of the most important and challenging issues that helps in understanding the physics of these fluids. For this purpose, the theory of micropolar fluids has been used. Thin film in three specific geometries, including flow downward on an inclined surface, flow on a moving ribbon, and flow downward on a vertical cylinder is considered. In order to solve the governing equations and obtaining the velocity and rotational fields, in the first two geometries, an analytical methods and in the third geometry a combined analytic and numerical methods are used with respect to the complexity of the equations. The rotational and velocity fields are plotted for all three cases and the results are discussed for different values of the parameters of a micropolar fluid. Also, the effect of the concentration of microelements in the fluid has been studied. It was observed that with the increase of the micropolar fluid parameter, the magnitude of velocity and rotation decreases.
Volume 18, Issue 116 (October 2021)
Abstract
The production of healthier fried foods requires the adaptation of industrial processes. In this context, air frying is an alternative to deep oil frying to Potato products such as chips to obtain with lower fat content. One of the most important points in designing, modeling and optimizing the frying processes is to precise determination the mass transfer parameters. Accordingly, in this research were investigated, the effects of mass transfer parameters such as effective penetration coefficient, mass dimensionless Biot number and mass transfer coefficient as well as activation energy in three temperatures and two air flow velocities. In this study, for the first time, air flow velocity was used as a variable factor in hot air frying, which also had a significant effect on decreasing moisture content.The results showed that all the mass transfer parameters as well as the relative constant of water reduction were directly proportional to the temperature and increased with increasing process temperature. At different flow velocities, all the parameters in except of the Biot number were increasing. The results of the activation energy obtained using the Arrhenius equation were also estimated at lower airflow velocities.
Volume 18, Issue 117 (November 2021)
Abstract
Ultraviolet radiation was used in the present study to process lemon juice. The designed UV system had five UV-C lamps and irradiation was performed based on the distance of the lamps (10, 20, and 30 cm) from the fluid layer and the circulation time (10, 20, and 30 minutes) of lemon juice in the system. Non-irradiated sample was also considered as a control treatment. The control and irradiated samples were filled in dark polyethylene bottles and stored at ambient temperature for 90 days. Immediately after irradiation and during the storage period, parameters such as pH, titratable acidity, total soluble solids, ascorbic acid content, color indices (L*, a*, and b*), browning index, as well as sensory attributes were evaluated. The pH, acidity, and total soluble solids did not show a definite trend. The results showed that among the color indices, L* decreased significantly, but a* and b* increased significantly during the storage period. The rate of color changes in irradiated samples from a distance of 10 cm was higher than other treatments. Irradiation also significantly reduced the ascorbic acid content of irradiated samples from a distance of 10 cm compared to other samples and control. However, the browning of irradiated samples from 10 cm distance was significantly less than that of irradiated samples from 20 and 30 cm distance. The score of the panelists indicated that irradiation and storage time altered the quality characteristics of lemon juice. The panelistschr('39') scores showed more acceptance of irradiated samples from 20 and 30 cm distance compared to irradiated samples from 10 cm distance. In general, the designed system in this study is not recommended for lemon juice processing due to the destructive effect of UV-C radiation on the content of ascorbic acid.
Volume 19, Issue 1 (7-2015)
Abstract
In recent years, due to the reverse logistics and particularly integration with direct Logistics is considered important in reducing supply chain costs. In this paper, a closed supply chain with multi-objective, multi-product and multi-period is designed. The objective functions consists of minimizing transportation costs between centers and processing cost within centers and centers construction and also the minimization of carbon dioxide is published within centers and carbon dioxide is published of transportation between centers. For this purpose, a mixed integer programming model is used and the problem is NP Hard. This model is superior to previous models,Considering multi-product and multi-period in relevant two objectives and also the relevant model constraints Production carbon dioxide between centers and within centers consideration. In order to integrate the supply chain's two goals the same phase and by multi-objective planning became an object. In order to validate the model and the influence of objective functions Weights several problem is designed and is solved with CPLEX 12.3 and in the end, the results are analyzed.
Volume 20, Issue 1 (January 2020)
Abstract
Nowadays, the interaction of oil droplets with gas bubbles plays an important role in many industrial, environmental and biological processes. Therefore, in this paper, the outcome of a collision between a silicon oil droplet and an air bubble in water has studied in order to identify the effective parameters in this process. For this purpose, an especial setup was built and four series of experiments in both dynamic (in which the relative velocity of collision is equal to the bubble velocity due to the Buoyancy force) and static conditions were carried out. The results of these experiments were presented and discussed in the form of several tables and pictures. In these experiments, a high-speed camera and image processing were used to gain a better understanding about bubble-drop coalescence qualitatively, and to obtain some quantitative information such as contact time, velocity, and kinetic and interfacial energies of bubbles and drops during the impact. The results of this study show that in addition to the spreading coefficient, the kinetic energy of bubble/droplet in the collision and their contact time, are also determinative parameters in the determination of the outcome of a collision. In the dynamic and static states, the effect of kinetic energy and contact time are more effective, respectively.
Farhad Hosseinali, Ali Asghar. Alesheikh,
Volume 20, Issue 2 (4-2013)
Abstract
Expansion of urban area is a well-known phenomenon in developing countries with population growth and the migration from villages to cities being two major factors. Those factors reduce the influence of efforts to limit the cities boundaries. Thus, spatial planners always look for the models that simulate the expansion of urban land-uses, and enable them to prevent unbalanced expansions of cities, and guide the developments to the desired areas. Several models have been developed and evaluated for simulating urban land-use expansions. Although these models are numerous, most of them have focused to simulate urban land-use expansions in sub-urban areas. The regional models that cover wider area are equally important. In this study, a new agent-based model has been developed and implemented to simulate urban land-use expansion in Qazvin and Alborz regions of Qazvin province, which cover 1620 square kilometres. In this model, land-use developers have been treated as computer agents that move in the landscape explicitly, and assess the state of parcels for development. The environment of the model is raster. The agents are categorized based on two scenarios. In the first scenario, all agents are of similar category and in the second scenario the agents are divided into five categories with different objectives. Then, the results of the two scenarios are compared. Due to the spatial essence of the problem, Geographical Information Systems (GIS) were used to prepare the environment of agents’ movement and search, and to aggregate and analyze the results.
To evaluate the model, data of year 2005 were used as the input and data of year 2010 were used for checking the results. By calibrating the parameters, the most desired configuration of the model was found in the second scenario, since the results were close to the reality as the Kappa index raised up to 78.17 percent. These results showed that the precision of the model to simulate land-use developments are of considerable quality. Thus, the model is able to detect the area that faced rapid urban expansions. Moreover, a comparison between the results of the two scenarios revealed that dividing the agents into categories with different aims and parameters will improve the outcome of the model. However, it is vitally important to determine the number of the agents in each category as well as their parameters precisely.
Volume 20, Issue 8 (August 2020)
Abstract
Nowadays, the interaction between gas bubbles and oil droplets plays an important role in the efficiency of many industrial processes. Therefore, it is of great importance to study the influencing factors on these processes. So, in the present paper, the effect of droplet and bubble size on the drainage time of the trapped intervening film between droplet and bubble was investigated. Six series of experiments were conducted for various sizes and three characteristic time scales including drainage time, coverage time, and rupture time were measured. Each of these experiments was repeated at least five times. The results showed that the drainage time changed independently of the droplet/bubble size. Moreover, it was observed that due to the nature of the phenomenon, the measured drainage times in each equivalent size are notably scattered, which means that the microscopic interactions in the water film and between bubble-droplet interfaces have significant impacts on the drainage time. Also, in the current experiment, it was found that the volume of the intervening film between droplet and bubble has no vital role in the drainage time of the mediate water film.
Volume 20, Issue 10 (October 2020)
Abstract
In this paper, miscible viscous fingering instability in a Darcy and non-Darcy porous media was studied through numerical solution and the formation and growth of finger patterns were discussed. According to the porosity coefficient, the media can be divided into Darcy and non-Darcy categories. Also, flow velocity and fluid used (Newtonian or non-Newtonian) are the factors that limit the use of Darcy’s relation. In this simulation, against most previous studies which had been used the two-phase Darcy’s structural equation to approximate examination of instabilities, a two-dimensional model was used. This model was based on coupling flow equations in porous media (Darcy or Brinkman) and transport of diluted species. The effects of increasing injection rates and viscosity changes were investigated based on Peclet non-dimensional number and viscous ratio on instabilities. Besides, a comparison was done between the results of Darcy’s and Brinkman’s solution at different porosity coefficient and viscosity ratio. Image processing techniques were performed to measure the break through time, perimeter of the interface, fractal dimension and sweep efficiency. With increasing viscosity in Darcy and Brinkman solution, the perimeter of the interface and fractal dimension were increased and more complex fingers generated. As a result, the sweep efficiency of the porous media reduces. In addition, the growth of the media porosity led to sweep efficiency. Finally, it was observed that with increasing injection velocity in Brinkman’s solution, the fingers complexity and perimeter of the interface increased and sweep efficiency decreased.