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Showing 10 results for مرتضایی
Volume 1, Issue 1 (4-2013)
Abstract
MaqamateHamidi is a good example of a text, which has emerged out of the previous culture and literature. This book has turned into a broad site in which various texts have been mixed in such a way that it represents an extensive array of genres. The main purpose of this study is the discovery and analysis of the intertexual relations in Maqamate Hamidi. To achieve this aim, we investigated twenty three Maqams in this this book in the light of Gerard Jeant’s Transtexuality Theory. The results indicated that MaqamateHamidi is a good example of intertexuality in a sense that different allusions to the Holy Quran are made, and also Arabaic poetry is extravagantly is used. Moreover, Hamidi’s book is greatly modeled on Hamadani and Harriri’s works, which attest to the intertextual nature and diversity of voices within this book. This intertexuality reinforces the coherence of meaning in this text, which is in line with Gerard Jeant’s Intertexuality Theory.
Volume 2, Issue 1 (4-2014)
Abstract
In spite of their apparent diversity and variety, Arabic and Persian maqamas are unified, which is the result of a common narrative structure. The main purpose of this study is to uncover this common structure. To this end, 124 maqamas including those of Hamadani, Hariri and Hamidi were analyzed based on Vladimir Propp’s morphology theory. The results indicated that Arabic and Persian maqamas are similar to each other in terms of character types and functioning. Moreover, in 31 functions and seven areas, they are in line with Propp’s theory. Such an approach allowed us to investigate all of these 124 maqamas within a single model and to conclude that narrative structure of these maqamas is the result of a single and primary plan, which has been effective in creation of this genre.
Volume 6, Issue 8 (9-2021)
Abstract
Lefevere considers translation as a kind of rewriting that is informed by the extra-systemic limitations like ideology and intra-systemic limitations like poetics. Adopting a descriptive-analytical approach, this research seeks to study the chebli’s rewriting of the ghazal 10th and 12th of Hafez The final result of this research, shows this rewriting is influenced by Poetic limitation and ideological . Manifestations of Lefeverechr('39')s view can be seen in the form of poems and manipulating the rhythm, music,inverting the use of pronouns, increasing some words, and domesticating,with the mystical attitude oon the rewriting of monastic symbols , and feast (bazm). Sometimes it is far from Lefevere ‘s view by exaggerating, unclear meaning and the same reception of "Pir" and "Sheikh".
Volume 6, Issue 20 (6-2018)
Abstract
Khaqani is a poet of Arrani style (Azerbaijani), and one of the most prominent features of this style is the use of various tools to make the discourse difficult. Having benefited from a reach cultural background besides a deep understanding of science and technology of his own era, Khaqani has created the magnificent images and has avoided any obscenity in his words. In other words, this diversity and variety in his poetic images may be due to the extent of Khaqani's information, research and his knowledge of historical interpretive books. One of the tools used by this poet to create his own images is allusion which can be considered a featured style of Khaqani due to its high frequency in his Divan. In his allusions, Khaqani occasionally refers to the indications which we cannot find their resources and references in the official and written literature; therefore we should search folk and oral narratives to find those references. In this research, we intend to look at the sources of some Shahnameh allusions of Khaqani which are based on oral and folk narratives and they are not mentioned in the official and written sources.
Volume 9, Issue 1 (12-2017)
Abstract
Sakestan has always been an important region during the Sassanian era. The mints of this region have been the most active of all in Iranshahr from the reign of Khosrow I to Khosrow II, demonstrating the full dominance of Sassanians over Sakestan. After the death of Khosrow II, the mints of the region were inactive intermittently. A coin from the reign of Ardashir III which is currently kept in Hazrat Masumeh Museum of Qom is the only gold coin found of this king and the first with the mint mark of Sakestan. In this research, apart from studying this coin and comparing the findings with archeological data from the late Sassanian period in Sakestan, the political situation of southeastern Iran after Khosrow II has been explored using the archeological and historical data. This paper is considered an original research concerning its objective, and a historical and analytical-descriptive research in terms of its methodology and context. Data and information gathering were carried out in the field and library. Based on the results of this study, it seems that Sakestan region was under the control of the main branch of Sassanian dynasty, loyal to Khosrow II during the late Sassanian period. The importance of this study is that it can clarify the political status of southeastern Iran in the late Sassanian period based on new findings.
Volume 10, Issue 3 (12-2010)
Abstract
Abstract Due to its simplicity, the structural engineering profession uses the nonlinear static analysis or pushover analysis. Modeling of such analysis requires the determination of the nonlinear properties of each component in the structure, quantified by strength and deformation capacities depending on the modeling assumptions. Pushover analysis is carried out for either user-defined nonlinear hinge properties or default-hinge properties, available in some programs based on the FEMA guidelines. While such documents provide the hinge properties for several ranges of detailing, the programs may implement averaged values. The user needs to be careful; becduse the misuse of default-hinge properties may lead to unreasonable displacement capacities for existing structures. This paper studies the possible differences in the results of push-over analysis due to default and user-defined nonlinear component properties. Four- and eight-story buildings were considered to represent low- and mediumrise buildings for this study. Plastic hinge length and transverse reinforcement spacing were assumed as effective parameters in the user-defined hinge properties. The observations showed that plastic hinge length and transverse reinforcement spacing have no influence on the base shear capacity, while these parameters have considerable effects on the displacement capacity of the frames. The comparisons pointed out that an increase in the amount of transverse reinforcement improves the Frames displacement capacity. Also Our findings clearly showed that the user-defined hinge model is better than the default-hinge model in reflecting the nonlinear behavior compatible with the element properties. However, although the default-hinge model is preferred due to its simplicity, the user should be aware of the circumstances provided in the program and thus should avoid the misuse of default-hinge properties.
Volume 15, Issue 1 (5-2015)
Abstract
One of the strengthening methods in reinforced concrete frame buildings is improving seismic behavior of such structures by means of steel bracing. When influenced by compressive stresses, traditional steel braces would buckle and are free of any ductility. As a result, efforts in order to restrain buckling problem for steel braces has led to creation of steel unbonded brace. In these braces, Eulerian buckling of central steel core is controlled by placing in a steel tube full of mortar. In this paper, RC buildings of 6, 12 and 18 stories are first designed based on standard 2800 and then controlled based on the rehabilitation regulation and the third edition of standard 2800. After analyzing and in order to improve seismic behavior, these buildings are strengthened by the use of common braces and steel unbonded braces and the columns of braced frames are also reinforced by concrete jacket. Totally, 42 models were analyzed by nonlinear static analysis (pushover analysis). The results indicate that structures with traditional braces have weakness in high level of drifts due to buckling of compressive braces and the energy absorption in 12 and 18 stories structures is even lower than non-strengthened structures. Nevertheless, this defect is removed by applying unbounded braces because of somehow identical behavior in extension and pressure as well as utilizing total capacity of these kinds of brace. Also, in comparison with structures with traditional braces and non-strengthened structures, a high level of energy absorption will be obtained. One of the strengthening methods in reinforced concrete frame buildings is improving seismic behavior of such structures by means of steel bracing. When influenced by compressive stresses, traditional steel braces would buckle and are free of any ductility. As a result, efforts in order to restrain buckling problem for steel braces has led to creation of steel unbonded brace. In these braces, Eulerian buckling of central steel core is controlled by placing in a steel tube full of mortar. In this paper, RC buildings of 6, 12 and 18 stories are first designed based on standard 2800 and then controlled based on the rehabilitation regulation and the third edition of standard 2800. After analyzing and in order to improve seismic behavior, these buildings are strengthened by the use of common braces and steel unbonded braces and the columns of braced frames are also reinforced by concrete jacket. Totally, 42 models were analyzed by nonlinear static analysis (pushover analysis). The results indicate that structures with traditional braces have weakness in high level of drifts due to buckling of compressive braces and the energy absorption in 12 and 18 stories structures is even lower than non-strengthened structures. Nevertheless, this defect is removed by applying unbounded braces because of somehow identical behavior in extension and pressure as well as utilizing total capacity of these kinds of brace. Also, in comparison with structures with traditional braces and non-strengthened structures, a high level of energy absorption will be obtained.
Volume 16, Issue 89 (7-2019)
Abstract
Honey types have many physicochemical and medicinal properties, depending on the herbaceous origin, geographic location, environmental factors, and honey bee species. In this study, the comparison of physicochemical characteristics and antioxidant activity of honey containing added Dill extract in the process and biological methods. Physicochemical tests including moisture, pH, acidity, viscosity, colorimetry, total phenolic compounds by Folin-Ciocalteu method and antioxidant activity (DPPH) for Dill honey, processed and biological honey including Dill extract, and natural honey (control i.e., Alfalfa honey ) were done. The results revealed that the highest antioxidant activity in natural honey was obtained (60.87%). Natural Alfalfa honey had antioxidant activity equal to 43.62%. Although the production of biological honey did not show favorable results with compared to natural honey, the results of processed honey did not significantly differ (P <0.05). Hence the production of processed honey is an effective method for producing honey with different therapeutic properties. But biological honey, in addition to its high cost, has lower antioxidant properties than natural and processed honey. Darker honey samples had higher amounts of phenolic compounds, flavones, and flavonols and increased antioxidant activity.
Volume 21, Issue 6 (12-2021)
Abstract
The science of seismic control of the structures always seeks to reduce and control the destructive effects of the forces which are produced during an earthquake event. However, the yield of the soil under intensified seismic loads can cause some irreversible effects on the structural elements and the structure may withstand the increased moments and the forces for which it is not formerly designed. This unfavorable phenomenon significantly affect the seismic response and performance of the structures, and will ultimately leads to disappearance of all functional goals that are sought to create in the structural design stage by the designer of the structure. In this research, by a relatively accurate three dimensional finite element modeling, from a high-rise concrete structure equipped with the active mass damper, and by examining the lesser-known aspects of the problem such as uplift of the foundation and the effects of nonlinear interaction of soil and structure, an attempt has been made to conduct a relatively comprehensive study on the questions of seismic control of structures equipped with active mass dampers due to the nonlinear effects of the underneath soil behavior. For this purpose, time history dynamic analysis was performed on the structural model under the effect of 22 horizontal records of distant basin earthquakes in x and y directions followed by the Appendix A of FEMA P695. The Ibarra model (a reviewed and modified model based on the Clough model) is used for modeling of the hysteresis behavior of concrete materials. The underneath soil is modelled by three springs approach presented in ATC 40 and FEMA 440 with equivalent stiffness based on soil modulus of elasticity and Poisson’s ratio of three categories (the main C category and upper and lower C and E categories ). To achieve the goal of optimization and evaluation of the active mass damper parameters (consist of tuning ratio, mass ratio and damping ratio), the mass damper spectra method with investigation of changes in structural responses has been used. The Fuzzy theory has been used to calculate the control force of an active mass damper. The results indicate that with respect to entrance of the structure to non-linear zone and its interaction with non-linear behavior of the soil, the efficiency of the active mass damper in uplift control of the foundation decreases, but a good efficiency is observed in the lateral displacement and inter story drift control. By evaluation of the three dimensional analysis results of a nonlinear soil structure system equipped with the active mass damper, the researchers observed that for the set of the recorded earthquake and based on the specifications considered for fuzzy algorithm, the active mass damper has a satisfactory effect in the control of displacements and drifts of the structure, in the amount of almost 15 percent. It was also identified that the active mass damper has a negligible effect on the foundation uplift in the structures which constructed on the hard soil. But when the soil becomes softer, a 3 percent mean decrease is observed in the uplift displacements in foundation.
Volume 22, Issue 3 (5-2022)
Abstract
Deep foundations are often used in a typical engineering project to transfer loads from heavy superstructures (bridges, highways, embankments and high-rise buildings) to the subsoil safely without subsidence or instability problems. In order to achieve an accurate and economical design in each of these projects, we must have a good understanding of how deep foundations behave, which can be done through analytical methods, numerical methods and experiments or experimental observations. Since a series of simplifications are usually performed in numerical and analytical methods, the use of experimental methods is selected to achieve a more desirable result. Experimental methods can be done by examining real models on site or performing experiments on a small-scale model in the laboratory (physical modeling), which due to lower cost, simplicity and reproducibility, usually physical modeling compared to Real on-site models are preferred. For physical modeling, various devices such as Simple Chamber (1 g), Calibration Chamber (CC) and centrifuge device can be used. The limitations and difficulties of these devices led to the recent introduction of a device called the Frustum Confining Vessel (FCV) for the physical modeling of deep foundations. In this device, which is in the form of an incomplete cone, by applying pressure to the bottom of the device, a linear stress gradient can be created along the central axis to be consistent with what is actually happening. Despite the many advantages that this device , it does not have a system for measuring the matric suction in unsaturated soils. Therefore, in this article, by embedding precision instruments in the sample made of this device in Amirkabir University of Technology (FCV-AUT) and implementing and loading of a pile in the soil inside it, It is possible to study the behavior of piles in unsaturated soil and the effect of moisture and matric suction on the load-displacement curve. The pile used in this research is an open-end pile which was implemented by driving method in Firoozkooh silty sand with gravimetric moisture contents of 0, 5, 10, 15 and 20% and in each case a load-displacement curve was drawn. The floor pressure applied in this research is equal to 100 kPa, Which was determined by placing several stress sensors at different soil depths and measuring the stress changes in depth. The following results were obtained after experiments:
- In the tested soil, up to 5% moisture content, no significant lateral friction is observed between the pile and the soil, and the end resistance, which is the result of plugging the soil inside the pile, provides most of the bearing capacity of the pile.
- From 5 to 15% moisture content, the lateral friction between the pile and the soil is gradually mobilized and while creating an initial jump in the curve of load-displacement, it increases the bearing capacity of the pile exponentially. But from 15% moisture content onwards, the initial slope decreases again due to the reduction of lateral friction.
- Considering the final bearing capacity of the pile as the load corresponding to 10% of the displacement of the pile head, the effect of matric suction on the changes of final bearing capacity was investigated. It was found that By increasing the amount of matric suction, first the final bearing capacity of the pile increases and after reaching a certain value, it decreases. The cause of this phenomenon is changes in wet soil behavior in different areas of the soil-water characteristic curve (SWCC) and is affected by various factors such as grain size, initial moisture content and soil density percentage.
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