Showing 53 results for شجاعی
Volume 6, Issue 5 (No.5 (Tome 26), (Articles in Persian) 2015)
Abstract
Many linguists have studied argument structure and argument realization in causative/inchoative alternations within the framework of lexicalist approaches. In the present paper, we will study, criticize and compare various derivatives of lexicalist approaches. Subsequently, we will test the main hypothesis underlying the mentioned accounts. In these accounts it is assumed that the verb’s lexical semantic features determine its argument structure and alternation. In this paper, based on Persian data, we will show that verb’s lexical semantics plays an important role in determination of its alternation, but the verb’s participation in causative alternation cannot be attributed sole to the verb’s semantic content. Overall, the findings of this survey cast doubt on the results of previous researches and show that other factors which transcend the verb’s lexical features determine its argument structure and its participation in causative alternation. With this regard, the other aim of this paper is to specify the factors affecting Persian verbs’ participation in causative alternation. Amongst these factors one can point to contextual factors such as semantic features of verb’s arguments and non-arguments alongside encyclopedic factors which coalesce at the level of logical form of the utterance.
Volume 8, Issue 1 (No.8- 2016)
Abstract
Iran revelution is a cultural and thinking event. we try here reply this question that what it is usese and capacities of discourses analysis relation to others approach (hermenutics and idieologic analysis) in study about iran revelution? here, at ferst we explain the problem then comprise discourses analysis with others approach (hermenutics and idieologic analysis) in study about think of Iran revelution 1n 1357. then, we present outcom and output . we perefer use of of discourses analysis relation to hermenutics approach because discourses analysis cover better power- knoledge and power-truth. so,discourses analysis go away from comprehention. this text believse that discourses analysis comprison with idieologic analysis can explain culthral and thinking dimension of Iran revelution. discourses analysis openes diffrence and new perspectives to this revelution. for example, in study about unpolitical thinkers and thinking elite, diversity and plural in revelution. or in study about think of Iran revelituion from ontologial historical view.
Volume 8, Issue 3 (Summer 2019)
Abstract
Aims: The aim of the current study was to determine the role of Avicennia marina’s primary production as well as other food sources in the diet of Longjaw thryssa, Thryssa setirostris (Broussonet, 1782) in an arid mangrove ecosystem using carbon stable isotopes of carbon (δ13C) and nitrogen (δ15N).
Material & Methods: We collected five potential food sources in the ecosystem including fresh and senescent leaves of Avicennia marina, particulate organic matter, microphytobenthos and sediment organic matter for further stable isotope analysis. Additionally, fishes were collected with a combination of set nets and seines. The muscle tissue (boneless and skinned, 5 g) was removed from the dorsum of fish.
Findings: Significant differences were found between carbon and nitrogen isotopes of different food sources (p < 0.05). Although, this was not significant for green and senescent leaves (p > 0.05). The average values of carbon and nitrogen isotopic ratios of T. setirostris were 15.93‰ and 13.01‰, respectively. The SIMMR model showed that the contribution of senescent and fresh leaves in the diet of T. setirostris was 15% and 10%, respectively.
Conclusion: The result of the current study emphasized a limited role for mangrove detritus in the diet of transient fishes in an arid mangrove ecosystem.
Volume 10, Issue 1 (Winter 2019)
Abstract
Enzymes of marine organisms are ideal candidates for biomonitoring of pollution in marine environments. For the widespread use of enzymes in industrial processes, carried out under certain physico-chemical conditions, their stability must be improved. In this study, for the first time, chitosan nanoparticles were used as matrices for augmenting the stability of Penaeus vannamei (Whiteleg shrimp)-derived purified proteases against metallic ions. For the electrostatic binding of the enzyme to the chitosan nanoparticles, the protein solution at a concentration of 7mg/ml was added to the nanoparticles, and incubated for 4 hours at 10°C. After 3 times rinsing with phosphate buffer of pH=7.5, the nano-enzyme was dissolved in 1ml phosphate buffer, and used for further studies. The results of this study showed that Fe2+ and Mn2+ significantly increased the enzyme activity, whereas a strong inhibitory effect was observed in the presence of Cd2+, Hg2+, Co2+, Ni2+, Cu2+ and Zn2+, and a weak inhibitory effect in the presence of Na+ and K+. The immobilized enzyme exhibited greater resistance to metal ions than its free counterpart. The free enzyme was susceptible to the presence of metal ions, and with the increment of their concentrations, enzyme activity declines. From this nexus, it could be inferred that the high stability of immobilized enzyme is due to the presence of chitosan nanoparticles. Stability retention of the immobilized enzyme at high concentrations of metal ions indicates the efficacy and utility of the immobilization method in industrial enzyme technology.
Volume 10, Issue 2 (Spatial Issue on Persian Gulf 2021)
Abstract
This study was conducted to investigate the morphological variation of Planiliza abu in the Tireh (Tigris Basin), Kor (Kor River Basin) and Jegin (Hormozgan Basin) rivers using traditional (TM) and geometric morphometric (GM) methods. For this purpose, a total of 62 specimens were collected using electrofishing device and Salik net. In the Lab, 21 morphometric traits were measured. Then, to extract the morphological data in the geometric method, 16 landmark-points were defined and digitized on the photographs taken from the left side of fish using tpsDig2 software. The results showed that the studied populations had significant differences in 7 morphometric traits (P<0.05). The differences in the geometric method were those of the head size, body depth, pectoral fin position and caudal peduncle length. Based on the results, GM method showed higher accuracy to reveal the morphological variations in the generalist species of Planiliza abu, which can inhabit a wide range of habitats.
Volume 10, Issue 2 (Spatial Issue on Persian Gulf 2021)
Abstract
This study was conducted to determine the temporal and spatial distribution of Opusia indica in the Hara Biosphere Reserve in the Persian Gulf. Seasonal sampling (four seasons) was performed from winter 2019 to autumn 2019. Sampling was done in five regions and three habitats within each region using metal quadrats with dimensions of 25 × 25 cm. In each habitat, environmental parameters including temperature, salinity, dissolved oxygen, pH along with organic matter and grain size were measured. The results showed that the abundance and biomass of Opusia indica have decreasing trend with increasing habitat complexity. Seasonally, the highest abundance and biomass were observed in winter and autumn, respectively, and the lowest abundance and biomass were observed in spring. There was a significant difference between habitats and seasons (p <0.05). Salinity showed a significant difference between habitats but didn't have seasonal changes. While temperature didn't show a significant difference between habitats, but it had seasonal changes. There was a significant difference between dissolved oxygen levels and pH between habitats and seasons. Significant changes were observed between habitat and seasons in sediment grain size, while the amount of organic matter showed only differences between habitats. Also, analysis of Kendall correlation between environmental factors (temperature, salinity, dissolved oxygen and pH) with abundance and biomass showed that there was a significant correlation between these environmental factors but no significant correlation was observed between abundance and biomass with the amount of organic matter. The results help to better understand the situation of this species in the mangroves ecosystem.
Koorosh Goudarzi, Vahid Jandeghi Shahi, ,
Volume 11, Issue 1 (6-2011)
Abstract
Passing manoeuvres and crosswind can have significant effects on the stability and fuel consumption of road vehicles. When two vehicles overtake or cross, they mutually influence the flow field around each other, and under certain conditions, can generate sever gust loads that acts as an additional forces on both vehicles. The forces acting on them are a function of the longitudinal and transverse spacings and of the relative velocity between the tow vehicles. In this paper, the models were designed to study the effects of various parameters such as the longitudinal and transverse spacing, the relative velocity and the crosswind on the aerodynamic forces and moments generated on the overtaken and overtaking vehicles using Ansys CFX. The aerodynamic forces have been predicted by a SST model solution of the Navier-Stokes equations for turbulent flow. The numerical predictions for the evaluation of aerodynamic coefficients agree well with the scaled-down air tunnel experimental work.
, , ,
Volume 11, Issue 2 (9-2011)
Abstract
In this study, TL characteristics of muffler shells are simulated using analytical and numerical model. Noise generated by engines, is radiated out into the atmosphere at the radiation end of the muffler and also from the shell of the muffler. So, accurate prediction of sound radiation characteristics from muffler shells is of significant importance in automotive exhaust system design. In analytical method, an exact solution is obtained by solving the vibration equation of the shell and acoustic wave equations simultaneously. Then, in numerical model, with the aid of SYSNOISE, commonly used commercial boundary element software, the coupled structural FEM-BEM model is applied to predict the TL of muffler shell. The predicted results agreed reasonably well with the experimental results. The effects of important design parameters likes thickness and geometrical shape are studied to provide design guidelines.
Volume 11, Issue 4 (12-2022)
Abstract
We studied the abundance, biomass and diet of Platevindex aff. tigrinus in the Hara Biosphere Reserve in the Persian Gulf. The seasonal sampling (two seasons) was conducted in winter 2018 and summer 2019. Samples were collected from six sites in Qeshm Island and Bandar Khamir. To determine the effect of environmental parameters on distribution of the species, temperature, salinity, pH, sediment grain size, total nitrogen and organic carbon were measured at each site. The results showed that the abundance of P. tigrinus was significantly higher in the winter compare to summer season. However, there was no significant difference in the biomass of the species between seasons. The PCA results showed that salinity, temperature and sediment grain size contributed to the separation of between seasons. The pH and total nitrogen followed the similar pattern in different sites and seasons. Although, temperature, salinity, sediment grain size, and organic carbon showed difference between seasons. The results showed that salinity and temperature were two important parameters in the distribution of the species during both seasons. The species was mainly feeding on the microphytobenthos during winter and on the sediment organic matter during summer.
Volume 12, Issue 2 (2-2021)
Abstract
Abstract
The history of children is among neglected fields in historical studies of Iran. Historians of social and cultural history of Iran has been working on some aspects of children's life in Qajar dynasty, such as education, but a large part of the life of this group has not been investigated and had been set in the side of Iranian histography. There for, the present article examines the part of the life of children (their training) during the Qajar period. with accordance to the wide range of the subject and the lake of data about children in the official and public historical texts of the Qajar dynasty on one hand and also reflects of the various aspects of the children's life in itineraries of foreign explorers in Qajar dynasty on the other hand the present subject, is investigated based on the itineraries of the foreign explorers of Qajar dynasty. This subject Emphasizing the foreign travelogues of the Qajar era has been studied. Findings of the research show that children's education includes school education, elementary education, secondary education and advanced and university education. In terms of education and educational facilities, most children are not in a good condition and their education is very simple and elementary have been. But gradually the situation got better. The research method in this paper is a historical one with a descriptive-analytical approach and a library data collection method.
Volume 12, Issue 2 (4-2023)
Abstract
The purpose of this research is to investigate the relative importance of Avicennia marina organic matter in the feeding of Ilisha melastoma fish in the Mangrove Biosphere Reserve; It was stable isotope approach. Three primary food sources including mangrove tree leaves, microphytobenthos and suspended organic particles were analyzed isotopically. The samples of primary food sources and fish are converted into pure and simple gases such as CO, CO2 and N2 after minimizing the size and turning into powder. Then the identified isotope ratios are compared with a measured standard and the exact amount of isotope formed in the sample is obtained. In this research, sampling was done seasonally in August in the summer season and February in the winter season of 2019 in the mangrove ecosystems of Bandar Khmer, Hormozgan province.In the summer season, the average stable carbon isotope of primary food sources fluctuated from -28.07 units per thousand for mangrove leaves to -13.58 units per thousand for microphytobenthos.This average in the winter season was obtained from -28.05 units per thousand for mangrove leaves to -13.54 units per thousand for microphytobenthos.The average stable nitrogen isotope of primary food sources in the summer season fluctuated from 1.44 units per thousand for microphytobenthos to 10.72 units per thousand for suspended organic particles.The results of this research showed that in the summer season, suspended organic particles with 63% and in the winter season, microphytobenthos with 45% play the most important role in providing the food needed by the small shemsk fish.
Volume 12, Issue 3 (9-2009)
Abstract
Objective: The aim of the present study was to investigate the effect of protein and DNA components of Toxoplasma gondii on maturation of dendritic cells and their efficiency in IL-12 production and proliferation of T cells.
Materials and Methods: for DC generation, Bone marrow cells were cultured in the presence of GM-CSF and IL-4 for 5 days. Tumor lysate and protein or DNA components of Toxoplasma gondii were added to the culture media and incubated for another 2 days. LPS was added as control for DC maturation. Proliferation of T cells were determined by MLR and IL-12 production was measured by ELISA kit. Maturation of dendritic cell were determined by flowcytometry.
Results: DCs treatment with protein components of Toxoplasma gondii caused a significant increase in IL-12 production and proliferation of T cells (P<0.001).
Conclusions: Different compositions of microbial body like protein and DNA components of Toxoplasma gondii can cause augmentation of antigen presentation capacity of DC and their IL-12 production capability. Among these components the protein was more effective as compared to DNA.
, Rohollah Talebitooti, ,
Volume 13, Issue 1 (4-2013)
Abstract
In this paper, an algorithm is presented based on using bspline function for optimizing tank cross section. This process minimizes fluid c.g. height and overturning moment and improve rollover threshold of tank vehicles. This algorithm receives tank capacity specifications as inputs and offers fourth order bspline function with 10 control points that has more roll stability, and then optimizes it for different filling conditions. This algorithm is based on the third order bspline function with 8 control points, initially. Therefore, with averaging and optimizing, range of control points is modified and the numbers of control points and degree of bspline function are increased. The results show that, the mutation rate is better to be between 4 and 6%, and the number of individuals in each generation should be at least 40. The algorithm presented in this paper, is a fast and accurate method for optimization of tank cross section in different filling conditions. The Algorithm based on GA maintains simplicity applicable for industries and specially has a rollover threshold of 10% higher than conventional tanks.
Volume 13, Issue 1 (9-2021)
Abstract
The purpose of this study is to investigate the emergence of new phenomena in the field of politics and power relations in Iran. Analyzing the history of political developments in contemporary Iran, based on Ernesto Laclau's account of "politics" and "people-based politics" and through the method of discourse analysis, we came to the conclusion that despite the multiplicity of movements, riots and resistance In the cities and villages against the local rulers and the central power, it is in the "tobacco movement" that we are confronted with a new kind of political action that calls for the demands and demands of the "people".
Volume 13, Issue 2 (5-2013)
Abstract
Abstract:
In this paper the experimental study of the flow pattern around a round wall jet has been carried out to investigate the effect of the bed roughness on the turbulence characteristics, including Reynolds stress and turbulence intensities. Measurements were conducted using the three-dimensional velocimeter, ADV and time series of the velocity components are used to investigate the variation of the turbulent flow parameters along the measuring domain. The results showed that by increasing the bed roughness, the streamwise and vertical turbulence intensities increase by downstream distance and for a specific bed roughness the streamwise turbulence intensity is higher than the vertical one. Furthermore, by going downstream from the jet entrance the bed shear stress reduces and by increasing the bed roughness, the bed shear stress has an increasing trend along the jet centerline. Location of the maximum bed shear stress does not change by changing the bed roughness.
Kiumars Mazaheri, Hossein Shojaee,
Volume 13, Issue 3 (6-2013)
Abstract
In most airbag systems, the gaseous mixture that fills up the airbag is produced by the fast combustion of a propellant in a combustion chamber called inflator. Since the process of gas production in the airbag inflator is a high-temperature combustion process, having a right understanding and precise control over the combustion in the airbag inflator has always been a challenge. In this paper, the numerical study of combustion process in a pyrotechnic inflator was carried out based on a Zero-Dimensional Multi Zones model. The parametric study show that the performance of inflator is more affected by the propellant characteristics such as mass, combustion index, and propellant temperature coefficient and is not significantly influenced by hardware elements of inflator. In order to simulate hybrid pyrotechnic inflator, the initial pressure of gas plenum was increased by 25 to 50 times. As a result, the performance both in combustion chamber and in discharge tank decreased. This lower temperature leads to a higher thermal efficiency.
Mohammad Hassan Shojaeefard, Abolfazl Khalkhali, Mojtaba Tahani, Behzad Salimian Rizi,
Volume 13, Issue 11 (1-2014)
Abstract
Centrifugal pumps performance is highly affected by working fluid viscosity. So, optimization of such pumps for pumping of viscose fluids is very important. In the present paper, multi-objective optimization of the centrifugal pumps is performed to obtain optimum impellers for pumping fluids with various viscosities at different volumetric flow rates. In this way, theoretical head and impeller hydraulic losses are considered as objective functions. Design variables defined in this optimization problem are passage width of impeller and outlet angle of blade. Diagrams of Pareto fronts and Pareto sets are extracted for different viscosities and different volumetric flow rates. Some trade-off optimum design points are selected from all non-dominated points using three different methods namely break point, TOPSIS and near to ideal point. Such methods are defined completely and employed to achieve compromising point successfully. Obtained optimum points contain interesting results which cannot be achieve without using proposed multi-objective optimization approach.
Mohamadhasan Shojaeifard, Rouhollah Talebitooti, Mansour Torabi, Reza Ahmadi,
Volume 14, Issue 1 (4-2014)
Abstract
In the present paper, power transmission interaction of multilayered sound isolation panels consists of porous, solid materials and air gaps using Transfer Matrix Method (TMM) has been considered. Considering the theories related to acoustical behavior of multilayered panel lined with poroelastic materials, detail explanation of Transmission Loss (TL) of a panel via TMM has been presented. Calculation of TL for a specified panel via TMM has been compared to existed experimental data in the literature and excellent agreement is observed. Next, based on this verified model, a multi-objective optimization of multilayered panel has been conducted using NSGA-II to maximize TL of panel while the panel weight is kept to a minimum. Results of two-objective optimization reveals, if the designer target is to achieve a specific average TL in the frequency band of 10 to 500 Hz, for a panel with constant width, selecting a panel with lower layers (three layers) can bring lower weight. But, if a higher average TL in the same frequency band is desired, a panel with more layers (six layers) has much better conditions in terms of weight.
Mohammad Hasan Shojaeefard, Abolfazl Khalkhali, Javad Zare, Mojtaba Tahani,
Volume 14, Issue 1 (4-2014)
Abstract
Heat pipe is an effective device for heat transferring. Using nanofluid as working fluid can significantly increase heat pipe thermal performance. But rate of the performance improvement, is dependent on parameters of the suspended nanoparticles in nanofluid. In this article, for the first time by considering nanoparticle volume fractions and diameters as design variables and the difference between the wall temperature of evaporator and condenser and liquid pressure drop as objective functions, the heat pipe performance has optimized. The used heat pipe is a cylindrical heat pipe with nanofluid as working fluid. Heat pipe thermal performance while using nanofluid has modeled by CFD method and then GEvoM has used to relate between design variables and objective functions. Using the modified NSGAII approach, pareto front has plotted and the values of recommended optimum points has obtained by mapping method. Recommended design points unveil interesting and important optimal design principles that would not have been obtained without the use of a multi-objective optimization approach.
Rouhollah Talebi, Mohammad Hassan Shojaeifard, Reza Ahmadi, Mohammad Reza Gheybi,
Volume 14, Issue 4 (7-2014)
Abstract
The objective of this paper is representation an analytical solution to calculate sound transmission loss (TL) of infinite thick transverse-isotropic cylindrical shell immersed in a fluid medium with an uniform external airflow and contains internal fluids where external sidewall of the shell excited by an oblique plane wave. In order to derive the governing equations the third-order shear deformation theory (TSDT) is used. Also, equation of motion of shell is obtained using Hamilton's principle. With solving shell vibration equations and acoustic wave equations simultaneously, the exact solution for TL is obtained. Transmission loss resultant from this solution is compared with those of other authors. The results also indicate that TSDT is more powerful than FSDT and CST, especially in high frequency and less R/h.
