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Volume 7, Issue 1 (Spring 2023)
Abstract
Research subject: Electromagnetic heating is one of the new methods of upgrading and increasing heavy oil extraction. In this method, electromagnetic waves will increase temperature, break heavy compounds, reduce viscosity, and improve and increase oil recovery.
Research approach: In this research, magnetic iron oxide nanoparticles (Fe3O4) were synthesized by the co-precipitation method, and the efficiency of these nanoparticles in the process of electromagnetic heating and heavy oil upgrading was investigated. Also, a comparison was made between the effect of these nanoparticles in the process of electromagnetic heating and activated carbon. In this process, oil samples containing 0.1% of Fe3O4 nanoparticles or activated carbon were irradiated with microwave (frequency 2.54 GHz and power 400 W) for 0 to 8 minutes, and the temperature and viscosity variation were investigated.
Main results: The results showed that microwave radiation increased the temperature of the samples. The temperature of the sample of crude oil, crude oil with activated carbon, and crude oil with Fe3O4 nanoparticles increased from ambient temperature to 70, 82, and 90°C, respectively, under wave radiation for 8 minutes. Also, the most significant decrease in viscosity was reported in 4 minutes: the viscosity of crude oil sample, crude oil with activated carbon, and crude oil with Fe3O4 nanoparticles under wave irradiation for 4 minutes decreased 295 mP.a to 261, 254, and 223 mP.a, respectively. In other words, the viscosity of the samples under wave irradiation for 4 minutes for crude oil, crude oil with activated carbon, and crude oil with Fe3O4 nanoparticles decreased by 11.5, 13.9 and 24.4%, respectively.
Volume 7, Issue 28 (11-2019)
Abstract
Rituals and arts, Iranian beliefs and traditions, and therefore the role and status of the ancient and innocent heroes of this land bring about diverse events in the rituals, myths and symbols of the Iranian Shiites, especially in Ashurā culture. The traces of these contents and thoughts can be found in many religious traditions. In this sense, the Ta'zieh manuscript is even more widespread because of its reputation among the general public. This article has attempted to show the impact of Siāvash's story on Ta'zieh version of Imam Hussein. Therefore the purpose of this research is through summarizing the two stories and their characteristics, to examine their similarities and their links with the mysterious birth of a celestial mother, their eternal aspect, their actions and reactions of nature to these heroes, their prediction and awareness of their destiny, their presence of supernatural, equipment, martyrdom, repetition of history, worship and protection, as well as common symbols and references. This research attempts to answer the question of how, in addition to tell a historical fact, it would be possible to combine the myths of mythical heroes with religious leaders in order to make the character more credible and even more praiseworthy.
Volume 8, Issue 2 (No. 8 (Tome 37), (Articles in Persian) 2017)
Abstract
Besides personal skills, individuals require some additional skills which are crucial to help them maintain a successful life in a community. One of them is the ability to communicate and develop social relationships. The current study aimed to investigate the effect of auditory training in social functions of elementary school bilingual Persian-Kurdish students in the town of Sar-pol-zahab. To implement the research in which a descriptive and analytical method is used, first the types of listening are defined and then the challenges and obstacles in the way of them happening are discussed. In addition, auditory training methods in teaching listening skills are explained for teachers. The data includes the assessment of the auditory skills improvement of Kurdish-speaker students whose auditory skills are being trained by teachers. The data is accumulated via questioners and processed by statistical methods. The results of this research are presented in the statistical analysis section.
Volume 8, Issue 35 (11-2020)
Abstract
Abstract
In textual criticism, it is necessary to pay attention to side sources and sometimes books of proverbs. Depending on the content and the main form of the proverbs, the editor can remove some of the ambiguities of the classical texts. Gradually, the use of these proverbs becomes more limited and turn into vague expressions for the scribes so that they may change them. For example, the phrase of "Shomar e khāne be bāzār rāst nemÎayad" (The counting of the house is not acceptable in the Bazar) is an ancient proverb, which means "Not matching a person's account at home with what he encounters in the market". This proverb at least has been used in Persian poetry and prose from the 5th century, and in our time, it has been used in Tajik Persian works. Sa'adi has used this proverb in the one of the verses of his Odes, but for the scribes of Saʿdī's Divan, it was not a familiar phrase, and hence, in most manuscripts and in all available editions of Divan and Odes, "arz e jame" (length of the clothes) has been distorted to the "arz e khane" (the length of the house). Most of the commentators of Sa'adi's Odes have trusted the text without paying attention to its transformation and distortion. They have interpreted the verse in such a way that it does not relate to Sa'adi's thought. In this article, the correct form of the Saʿdī's verse has been presented relying on some of the manuscripts of Sa'di's Divan and the background and meaning of this proverb.
Research Background
In this article, some distorted examples have been mentioned in the literary texts. For example, in the articles "The correction of some verses in Sanaī’s Hadiqa using Farhang-e jahāngīrī", "Pey e ŝirân gereftan va rân e gurân xordan", "The Necessity of re-correcting Katebi Neishaburi's Divan of Odes" (Khosravi, 2014, pp. 346-347; Harandi, 2018, pp. 99- 113; Bashiri et al., 2018, pp. 85-113), there are some evidence to show that the conversion and distortion of a proverb has taken the text away from its original form.
Aims, questions, and assumptions
The proverbs are one of the side sources that are effective in textual criticism. Sometimes, the proverbs have been changed due to the unfamiliarity of the scribes, but according to their prevalence in literary texts, the correct form of that text can be found.
To this aim, the following research questions are raised:
1. How do factors such as neglecting the meaning and ignoring proverbs have distorted the text?
2. How does investigating the use of proverbs in literary texts help the editor to edit the text?
3. How commentators' trust in correcting the meaning of proverbs written in some edited texts had diverted their minds from the original form of the text?
Discussion
In the study of classical texts, we find that the change and conversion of the proverb has sometimes taken the text away from its correct form. In this article, we have chosen a verse of Sa'di as an example to show that neglecting the proverb “Shomar e khāne be bāzār rāst nemÎayad" has caused ambiguity in the meaning of the verse. As in some manuscripts and all editions of Odes, “arz e jame” has been changed to " arz e khane” (Foroughi, 2007, p. 469; Yousefi, 2006, p. 19)
Searching this proverb in the classical texts, we found its other forms and mentioned its meaning and application in the literary texts, and showed that how researchers' trust in the Foroughi's edition of Sa'di's Odes prevented their minds from grasping the correct meaning of the verse and led to its misinterpretation and explanation.
The findings show that this proverb has been prevalent in Persian poetry and prose since, at least, the fifth century, and in texts such as Manouchehri Damghani's Divan (2006, p. 20), Nafsat ol- Masdoor (Zaidari Nesavi, 2002, p. 100) and Rouh-ol-Arvah (Samani, 2010, p. 538) and in our time has also been used in Tajik Persian works (also see Dehkhoda, 1984, 2/953; Zolfaghari, 2010, 1/834).
Conclusion
In textual criticism, it is necessary to pay attention to side sources. For example, the study of a hemistich of Sa'di's Odes and the commentators' descriptions of that verse clearly shows that due to the inaccuracy of the text, even the most meticulous scholars have misunderstood the meaning of the verse. The confidence in Foroughi's correction has prevented them to perceive the possibility of errors in the text, and consequently, the mistake in recording the hemistich is hidden. Most surprising of all is the distraction of Yousefi's precise notion, which did not pay attention to the correct recording of some manuscripts. The editors and commentators of Sa'di's Odes have not discussed the ambiguity of the second hemistich, but in explaining the verse according to the power of their imagination, they have made a new theme or taken it from someone else.
References
Bashiri, B., Amani, R., & Farzi, H. (2018). The necessity of re-correcting Katebi Neishaburi’s Divan of Ode. Textual Criticism of Persian Literature, 54, 85-113.
Dehkhoda, A. (1984). Dehkhoda's proverbs. Amirkabir.
Khosravi, M. (2014). The correction of some Verses in Sanaī’s Hadiqa using Farhang-e Jahāngīrī. Name-ye Farhangestan (Sub-continent), 3, 339-350.
Sa'di, M. (2007). Kolliāt (edited by Mohammad Ali Forughi). Amir Kabir.
Sa'di, M. (2006). Sa'di's Odes (edited by Gholamhossein Yusofi). Sokhan.
Samaani, Sh. (2010). Spirit of all spirits in understanding the names of the all good (edited by Najib Mile Heravi). Elmi va Farhangi.
Nandimi Harandi, M. (2018). Pey e ŝirân gereftan va rân e gurân xordan. Culture and Folk Literature, 20, 99-113.
Zolfaqari, H. (2010). The dictionary of Persian proverbs. Moin.
Zidari Nesavi, Sh. (2002). The sigh of a sad heart (edited by Amir Hassan Yazdgerdi). Toos.
In textual criticism, it is necessary to pay attention to side sources and sometimes books of proverbs. Depending on the content and the main form of the proverbs, the editor can remove some of the ambiguities of the classical texts. Gradually, the use of these proverbs becomes more limited and turn into vague expressions for the scribes so that they may change them. For example, the phrase of "Shomar e khāne be bāzār rāst nemÎayad" (The counting of the house is not acceptable in the Bazar) is an ancient proverb, which means "Not matching a person's account at home with what he encounters in the market". This proverb at least has been used in Persian poetry and prose from the 5th century, and in our time, it has been used in Tajik Persian works. Sa'adi has used this proverb in the one of the verses of his Odes, but for the scribes of Saʿdī's Divan, it was not a familiar phrase, and hence, in most manuscripts and in all available editions of Divan and Odes, "arz e jame" (length of the clothes) has been distorted to the "arz e khane" (the length of the house). Most of the commentators of Sa'adi's Odes have trusted the text without paying attention to its transformation and distortion. They have interpreted the verse in such a way that it does not relate to Sa'adi's thought. In this article, the correct form of the Saʿdī's verse has been presented relying on some of the manuscripts of Sa'di's Divan and the background and meaning of this proverb.
Research Background
In this article, some distorted examples have been mentioned in the literary texts. For example, in the articles "The correction of some verses in Sanaī’s Hadiqa using Farhang-e jahāngīrī", "Pey e ŝirân gereftan va rân e gurân xordan", "The Necessity of re-correcting Katebi Neishaburi's Divan of Odes" (Khosravi, 2014, pp. 346-347; Harandi, 2018, pp. 99- 113; Bashiri et al., 2018, pp. 85-113), there are some evidence to show that the conversion and distortion of a proverb has taken the text away from its original form.
Aims, questions, and assumptions
The proverbs are one of the side sources that are effective in textual criticism. Sometimes, the proverbs have been changed due to the unfamiliarity of the scribes, but according to their prevalence in literary texts, the correct form of that text can be found.
To this aim, the following research questions are raised:
1. How do factors such as neglecting the meaning and ignoring proverbs have distorted the text?
2. How does investigating the use of proverbs in literary texts help the editor to edit the text?
3. How commentators' trust in correcting the meaning of proverbs written in some edited texts had diverted their minds from the original form of the text?
Discussion
In the study of classical texts, we find that the change and conversion of the proverb has sometimes taken the text away from its correct form. In this article, we have chosen a verse of Sa'di as an example to show that neglecting the proverb “Shomar e khāne be bāzār rāst nemÎayad" has caused ambiguity in the meaning of the verse. As in some manuscripts and all editions of Odes, “arz e jame” has been changed to " arz e khane” (Foroughi, 2007, p. 469; Yousefi, 2006, p. 19)
Searching this proverb in the classical texts, we found its other forms and mentioned its meaning and application in the literary texts, and showed that how researchers' trust in the Foroughi's edition of Sa'di's Odes prevented their minds from grasping the correct meaning of the verse and led to its misinterpretation and explanation.
The findings show that this proverb has been prevalent in Persian poetry and prose since, at least, the fifth century, and in texts such as Manouchehri Damghani's Divan (2006, p. 20), Nafsat ol- Masdoor (Zaidari Nesavi, 2002, p. 100) and Rouh-ol-Arvah (Samani, 2010, p. 538) and in our time has also been used in Tajik Persian works (also see Dehkhoda, 1984, 2/953; Zolfaghari, 2010, 1/834).
Conclusion
In textual criticism, it is necessary to pay attention to side sources. For example, the study of a hemistich of Sa'di's Odes and the commentators' descriptions of that verse clearly shows that due to the inaccuracy of the text, even the most meticulous scholars have misunderstood the meaning of the verse. The confidence in Foroughi's correction has prevented them to perceive the possibility of errors in the text, and consequently, the mistake in recording the hemistich is hidden. Most surprising of all is the distraction of Yousefi's precise notion, which did not pay attention to the correct recording of some manuscripts. The editors and commentators of Sa'di's Odes have not discussed the ambiguity of the second hemistich, but in explaining the verse according to the power of their imagination, they have made a new theme or taken it from someone else.
References
Bashiri, B., Amani, R., & Farzi, H. (2018). The necessity of re-correcting Katebi Neishaburi’s Divan of Ode. Textual Criticism of Persian Literature, 54, 85-113.
Dehkhoda, A. (1984). Dehkhoda's proverbs. Amirkabir.
Khosravi, M. (2014). The correction of some Verses in Sanaī’s Hadiqa using Farhang-e Jahāngīrī. Name-ye Farhangestan (Sub-continent), 3, 339-350.
Sa'di, M. (2007). Kolliāt (edited by Mohammad Ali Forughi). Amir Kabir.
Sa'di, M. (2006). Sa'di's Odes (edited by Gholamhossein Yusofi). Sokhan.
Samaani, Sh. (2010). Spirit of all spirits in understanding the names of the all good (edited by Najib Mile Heravi). Elmi va Farhangi.
Nandimi Harandi, M. (2018). Pey e ŝirân gereftan va rân e gurân xordan. Culture and Folk Literature, 20, 99-113.
Zolfaqari, H. (2010). The dictionary of Persian proverbs. Moin.
Zidari Nesavi, Sh. (2002). The sigh of a sad heart (edited by Amir Hassan Yazdgerdi). Toos.
Volume 10, Issue 19 (9-2023)
Abstract
In some of the ancient translations and exegesis of the Quran in the Herat region, a specific word, "Ḥin," has been used whose meaning is unclear. In most ancient Persian cultures, the word "Ḥin" is considered specific to the ancient Shirazi dialect and means "Is"; however, examining this word in the ancient translations of the Quran in the Herat region indicates differences in its usage and meaning compared to Shirazi texts. In this descriptive-analytical article, all instances of this word in the translations of the Quran in the Herat region have been collected in the first stage. Then, by referring to the Quranic text and equivalents of this word in Arabic on one side, and tracing the roots and explaining the ancient applications and meanings of this word in Middle Persian texts and early Islamic periods on the other side, an effort has been made to clarify and analyze the meanings and applications of this rare word in Quranic translations. The crucial results obtained from this research are as follows: In most cases, "Ḥin" is mechanically used without considering the grammatical structure of the Persian language in the translation of phrases such as "Hādhā," "Hātayni," "Hāʼulāʼ," "Yawmaʼidhin," "Kadhālika," "Hunālika," "Alʼān," and "Ka" and therefore, it is not considered a verb in Arabic nor as an auxiliary verb in Persian translation. "Hunna" is used in translating terms from words like "Hādhā, Hātayni, Hāʼulāʼ, etc." which signify warning, attention, and emphasis. In cases where "Hunna" seems to have no clear equivalent in the Arabic verse and is used as an auxiliary verb/agent, it carries the same emphasis and warning meaning mentioned earlier. Therefore, as conclusion, in the Heravi genre of Persian language, "Hunna" as a form of the third-person singular verb h- "Is" has preserved one of the semantic components of this verb from the Middle Persian period, namely certainty, definiteness, and emphasis on the timeless nature of documents, and transferred it to the new era of the Persian language.
Volume 13, Issue 62 (5-2025)
Abstract
Fictional literature has various aspects, one of which is its regional character. In such stories, besides language, nature and imagery derived from the author’s specific region, local legends, indigenous music and melodies, popular beliefs, proverbs, local customs and rituals, etc., are manifested. Folk culture is closely linked to regional literature. Folk culture contrasts with official and elite culture, which unlike folk culture that is mostly oral, is written and related to the masses. When these elements are employed in literature, they give the works a distinctive regional color, known as regional literature. Understanding and analyzing fictional literature requires examining the relationship between the author and their environment; the conscious and unconscious influences the author receives from their environment and region, which affect the structure, meaning, and development of the narrative. Seyyed Hossein Mirkazemi is among contemporary writers whose works prominently feature the regional character of northern Iran. This study descriptively-analytically examines the regional character in one of his works, The Olive Garden of the Eye, revealing the abundant presence of northern Iranian regional elements, especially from the Gorgan area: natural elements and related imagery, linguistic and lexical features, beliefs and customs, places, occupations, and even specific social and political events-all serving to naturalize the story’s setting, events, and the realism of its characters.
Research background
No prior research has been conducted on this topic in the works of Seyyed Hossein Mirkazemi, but valuable studies exist in the field of regional literature. Gahraman Shiri has focused on regional literature since 2003 and more comprehensively in his book Schools of Fiction Writing in Iran (2008). Jafari (Ghanavati) studied oil and its reflections in Khuzestani fiction writers (2004). Sadeghi Shahpar researched the five regional domains in contemporary Iranian fiction (2012), and Moshtagh Mehr and Sadeghi Shahpar analyzed regional features in northern Iranian fiction (2010). Other studies include manifestations of Turkmen folk culture in the novel Yurt (2021) by Dastpisheh, Nabilu, and Tahmasebi, and beliefs and folk literature elements in the novel Savushun (2014) by Kafi and Ameri.
Theoretical framework
One aspect of fictional literature is its regional character, which aims to explain the reciprocal relationship between humans and their environment. This helps identify a writer’s stylistic identity and discover elements that distinguish one region from others. Understanding fictional literature requires analyzing the bond between the author and their environment. This study, using a descriptive-analytical method, examines the regional features in The Olive Garden of the Eye by Seyyed Hossein Mirkazemi-a contemporary writer with a strong northern regional influence. The findings include:
Regional imagery: Includes tangible-to-tangible similes and three categories of similes, that is, animal, nature, and human-made products.
Local language and dialect: Language is a tool for communication and the first step to understanding a region’s culture. In this work, it appears in two forms:
Vocabulary and expressions: Mirkazemi, a graduate in education and a teacher in Golestan province’s towns and villages, is committed to preserving folk culture and uses abundant regional vocabulary and expressions in his works.
Laments and folk songs: Each region’s people have unique poems, songs, and laments, recited in different emotional states.
Reflection of the author’s regional material folklore (Customs and Rituals): Regional literature reflects the characteristics of a specific region, providing valuable information about beliefs, customs, proverbs, and folk themes. Mirkazemi, interested in folk literature, mentions various beliefs, customs, traditions, and local norms.
In the third chapter, titled Nowruz Stories, customs related to Nowruz such as Nowruz reading, copper cleaning, pottery making, Samanu cooking, and the Chaharshanbe Suri ceremony are described.
Architecture: Houses with tiled roofs and white stripes between them are depicted.
Occupations: The author describes various professions and duties of men and women from his childhood, reflecting his enthusiasm for preserving folk culture and customs.
Conclusion
The study shows that The Olive Garden of the Eye belongs to regional fiction. Although not all events, characters, and settings are exclusively from northern Iran, the story’s background is imbued with the color and character of northern Iran, especially the Gorgan region. Many features such as nature and regional imagery, local language and dialect, beliefs and customs, architectural style, occupations, and even some specific social and political events serve this purpose.
Additional Context on Seyyed Hossein Mirkazemi
Born on 27 Ordibehesht 1321 in Gorgan, Seyyed Hossein Mirkazemi is recognized as the father of Golestan’s fictional literature. Unlike predecessors like Nematollah Ghazi and Parvin Sepahri, who began in the 1950s and whose works were mostly serialized, Mirkazemi professionalized and expanded this literary form. His first non-fiction book Knowledge and Insight in the Village was published by the Ministry of Education. His first fiction work Alaman (meaning “raid” in Turkmen) is a collection of rural stories, some incomplete due to censorship. His famous novel Yurt is a historical, epic, and romantic work, noted for its majestic prose, literary devices, and linguistic richness, awarded at the Gardoon Literary Festival. He also collected folk tales and contributed to children’s literature innovatively.
Mirkazemi emphasizes the fusion of story and legend, believing that modern Iranian fiction can be enriched by integrating traditional folklore, as seen in Yurt, Zan va In Goman, and The Olive Garden of the Eye. He advocates for familiarity with Iranian and international folklore to innovate in storytelling.
Research background
No prior research has been conducted on this topic in the works of Seyyed Hossein Mirkazemi, but valuable studies exist in the field of regional literature. Gahraman Shiri has focused on regional literature since 2003 and more comprehensively in his book Schools of Fiction Writing in Iran (2008). Jafari (Ghanavati) studied oil and its reflections in Khuzestani fiction writers (2004). Sadeghi Shahpar researched the five regional domains in contemporary Iranian fiction (2012), and Moshtagh Mehr and Sadeghi Shahpar analyzed regional features in northern Iranian fiction (2010). Other studies include manifestations of Turkmen folk culture in the novel Yurt (2021) by Dastpisheh, Nabilu, and Tahmasebi, and beliefs and folk literature elements in the novel Savushun (2014) by Kafi and Ameri.
Theoretical framework
One aspect of fictional literature is its regional character, which aims to explain the reciprocal relationship between humans and their environment. This helps identify a writer’s stylistic identity and discover elements that distinguish one region from others. Understanding fictional literature requires analyzing the bond between the author and their environment. This study, using a descriptive-analytical method, examines the regional features in The Olive Garden of the Eye by Seyyed Hossein Mirkazemi-a contemporary writer with a strong northern regional influence. The findings include:
Regional imagery: Includes tangible-to-tangible similes and three categories of similes, that is, animal, nature, and human-made products.
Local language and dialect: Language is a tool for communication and the first step to understanding a region’s culture. In this work, it appears in two forms:
Vocabulary and expressions: Mirkazemi, a graduate in education and a teacher in Golestan province’s towns and villages, is committed to preserving folk culture and uses abundant regional vocabulary and expressions in his works.
Laments and folk songs: Each region’s people have unique poems, songs, and laments, recited in different emotional states.
Reflection of the author’s regional material folklore (Customs and Rituals): Regional literature reflects the characteristics of a specific region, providing valuable information about beliefs, customs, proverbs, and folk themes. Mirkazemi, interested in folk literature, mentions various beliefs, customs, traditions, and local norms.
In the third chapter, titled Nowruz Stories, customs related to Nowruz such as Nowruz reading, copper cleaning, pottery making, Samanu cooking, and the Chaharshanbe Suri ceremony are described.
Architecture: Houses with tiled roofs and white stripes between them are depicted.
Occupations: The author describes various professions and duties of men and women from his childhood, reflecting his enthusiasm for preserving folk culture and customs.
Conclusion
The study shows that The Olive Garden of the Eye belongs to regional fiction. Although not all events, characters, and settings are exclusively from northern Iran, the story’s background is imbued with the color and character of northern Iran, especially the Gorgan region. Many features such as nature and regional imagery, local language and dialect, beliefs and customs, architectural style, occupations, and even some specific social and political events serve this purpose.
Additional Context on Seyyed Hossein Mirkazemi
Born on 27 Ordibehesht 1321 in Gorgan, Seyyed Hossein Mirkazemi is recognized as the father of Golestan’s fictional literature. Unlike predecessors like Nematollah Ghazi and Parvin Sepahri, who began in the 1950s and whose works were mostly serialized, Mirkazemi professionalized and expanded this literary form. His first non-fiction book Knowledge and Insight in the Village was published by the Ministry of Education. His first fiction work Alaman (meaning “raid” in Turkmen) is a collection of rural stories, some incomplete due to censorship. His famous novel Yurt is a historical, epic, and romantic work, noted for its majestic prose, literary devices, and linguistic richness, awarded at the Gardoon Literary Festival. He also collected folk tales and contributed to children’s literature innovatively.
Mirkazemi emphasizes the fusion of story and legend, believing that modern Iranian fiction can be enriched by integrating traditional folklore, as seen in Yurt, Zan va In Goman, and The Olive Garden of the Eye. He advocates for familiarity with Iranian and international folklore to innovate in storytelling.
Volume 14, Issue 8 (11-2014)
Abstract
This paper presents an elastic parametric analysis for the purpose of investigating the limit angular speed, displacement and stresses in rotating disks made of functionally graded materials (FGMs) based on Tresca yield criterion. The material properties obey the power law in radial direction. The Poisson’s ratio due to slight variations in engineering materials is assumed constant. For different values of inhomogeneity constant, limit angular speed, displacement and stresses in radial direction are plotted and for the commencement of the plastic flow, different states are investigated. state1: onset of plastic flow at the inner radius, state2: onset of plastic flow at the outer radius, state3: onset of plastic flow as the simultaneously at both radii and state4: onset of plastic flow between the inner and outer radii. To the best of the researchers’ knowledge, so far, in the papers which have been dealing with the investigation of onset yield analysis, the density and yield stress has been assumed constant; however, in this paper by assuming varying density and yield stress in rotating disks made of functionally graded materials and comparing results obtained by fixing these parameters, it has been observed that taking the density as a constant value is wrong and varying it has significant effects on the stresses.
Volume 14, Issue 9 (12-2014)
Abstract
A new complete system model of a flapping wing has been derived which consists of all effective parameters. Flapping mechanism can deliver maneuverability as well as low speed flight capability in MAVs. Here a validated aeroelastic model is being developed based on the wing torsional deformation assumption. Based on the proposed model complete parameter study could be performed and consequently the optimization requirements can be extracted. Experimental results of a static test stand have been used for validation. Performance indices, composed of force generated, power consumption and efficiency are depicted in terms of stiffness and kinematic properties. The average behavior is being referred. It is revealed that by changing frequency and speed, the optimum values for stiffness and amplitude are independent. Therefore using suitable kinematics one can utilize specified constant stiffness to optimize the flapping robot flight.
Volume 15, Issue 3 (9-2015)
Abstract
This research is devoted to the adaptive solution and control point net improvement of axisymmetric problems in isogeometric analysis using the error estimation based methods for stress recovery. For this purpose, after the calculation of the energy norm, the estimated value of error in the vicinity of each control point is assigned to the neighboring members of a hypothetical truss-like structure as an artificial thermal gradient. By analysis of this network of rods under the temperature variations a new arrangement of control points is obtained. Repeating this process of thermal isogeometric analysis will eventually lead to a better distribution of errors in the domain of the problem and results in an optimal net of control points for the calculation of the integrals. To demonstrate the performance and efficiency of the proposed method, two axisymmetric elasticity problems with available analytical solutions are considered. The obtained results indicate that this innovative approach is effective in reducing errors of axisymmetric problems and can be employed for improving the accuracy in the context of the isogeometric analysis method. Innovated method of this research focuses on adaptive analysis and Network improving of axisymmetric problems in isogeometric analysis using error estimation methods based on stress recovery. For this purpose after calculation the energy norm, estimated value of error in the vicinity of control points is assigned to each rod as the thermal gradient. Thus after analyzing the hypothetical rods network under the temperature changes a new arrangement of control points and knot vectors can be obtained. The use of multi-cycle of this process in isogeometric analysis will lead to a better distribution of errors in the domain and thus achieve optimal network to calculate the integrals. To measure the efficiency of this method and demonstrate the increased carefully in axisymmetric problems, which has the analytical solution, two elasticity problem is evaluated. The results show that innovative network improving method has good efficiency to reduce the error rate and can be used to increase the accuracy of isogeometric analysis results. Innovated method of this research focuses on adaptive analysis and Network improving of axisymmetric problems in isogeometric analysis using error estimation methods based on stress recovery. For this purpose after calculation the energy norm, estimated value of error in the vicinity of control points is assigned to each rod as the thermal gradient. Thus after analyzing the hypothetical rods network under the temperature changes a new arrangement of control points and knot vectors can be obtained. The use of multi-cycle of this process in isogeometric analysis will lead to a better distribution of errors in the domain and thus achieve optimal network to calculate the integrals. To measure the efficiency of this method and demonstrate the increased carefully in axisymmetric problems, which has the analytical solution, two elasticity problem is evaluated. The results show that innovative network improving method has good efficiency to reduce the error rate and can be used to increase the accuracy of isogeometric analysis results.
Volume 15, Issue 4 (6-2015)
Abstract
Forming media in metal forming processes is so important. Since the forming media in Ball deep-drawing process is discrete, it is quite flexible. In this paper, thickness distribution and required force for forming of conical part by ball deep-drawing and conventional deep-drawing processes using finite element simulation and experimental stages, were studied. In this research, sheets were used made St14 steel and brass wit 1mm thickness. The experimental results are in good agreement with simulation results. The results showed the sample formed by conventional deep-drawing process had more uniform thickness distribution than ball deep-drawing, but the maximum thinning in the parts of ball forming process was less than conventional deep-drawing process. Also it was observed that required force for ball deep drawing process is more than the conventional deep-drawing process. It was observed that with increasing radius of the input die, the force required to stretch the ball deep-drawing and ball processes is decreased, also with increasing radius of the input die is reduced thinning amount. It was noted that one of the advantages of ball deep drawing process than traditional deep drawing process is achieved a negative slope part.
Volume 16, Issue 5 (7-2016)
Abstract
Polymeric foams have a cellular structure composed of a polymeric matrix with gaseous cells which achieved by expansion of a blowing agent in polymer melt matrix during a foaming process. In the present study, the bubble expansion step in Polystyrene/CO2 batch foaming process was simulated and compared to the reported experimental results. A single spherical bubble surrounded by an incompressible viscoelastic fluid (upper-convected Maxwell model) was considered. To calculate concentration profile in the shell, mass diffusion equations were solved using finite element method, potential function definition and integral methods. The predicted results show that when the gas concentration profile obtained by finite element method and the concentration gradient near the bubble-shell interface was used to calculate the pressure inside the bubble, the predicted results were in good agreement with the experimental ones which there was less than 1% error at each foaming time. The effects of the thermo-physical and rheological properties on the bubble growth dynamics were also studied and It was found out that increasing the diffusivity coefficient by factor of 10 would increase the bubble size up to 1.5 times, whereas increasing the viscosity by 3 folds would only change the bubble size about 2% showing that the bubble growth step in foaming process was a mass transfer controlled process.
Volume 16, Issue 7 (9-2016)
Abstract
In this paper, a trajectory tracking control strategy for a quadrotor flying robot is developed. At first, dynamic model is obtained by lagrange-euler approach. Then, control structure, consisting of a model-based predictive controller, has been used based on state space error to track transitional movements for reference trajectory and also robust nonlinear H∞ control is applied for stabilizing the rotational movements and reject the external disturbance. In both controllers the integral of the position error is considered, allowing the achievement of a null steady-state error when sustained disturbances are acting on the system. The external disturbances is considered as aerodynamic torques. If uncertainties increase, the designed control system will be unable to track and stabilizing perform properly and completely. So finally, in order to eliminate the effects of parameter uncertainties the recursive least squares is used for estimating mass and moment inertia parameters which are linear and it is applied to the control system. Simulation results show that by using estimation of system parameters, the proposed control system has a promising performance in terms of stabilization and position tracking even in the presence of external disturbance and parametric uncertainties.
Volume 16, Issue 10 (1-2017)
Abstract
In this paper a nonlinear controller is going to be designed for micro-beam’s deflections under mechanical shock effects. The micro-beam is supposed to undergo mechanical shocks. Mechanical shocks are one of the failure sources and the controller is to considerably suppress shock’s unfavorable effects. Half-Sine, rectangular and triangular pulses are chosen as reference shock signals to represent true complicated shock signals in nature which consist of different harmonics. Two layers of electrodes are placed in both sides of the micro-beam and they are used to actuate the micro-beam by different voltage levels. Upper layer is specifically meant for control purpose. Nonlinear equations governing micro-beam’s deflection dynamics are derived, discretized by Galerkin method to a set of nonlinear duffing type ODE and used to investigate micro-beams response to each shock input signal. Controller design is based on a simple nonlinear model formed by micro-beam’s first mode shape. Proper second order behavior is generated by feedback linearization method as controller logic. Finally controller performance and shock rejecting capability is evaluated by numerical simulations. Controller is shown to be very effective in diminishing shock unfavorable effects and postponing pull-in instability by numerical simulations.
Volume 16, Issue 11 (1-2017)
Abstract
In this paper, using both linear and nonlinear identification methods based on iterative and recursive least-square, the performance of a backstepping control system of a quadrotor in the presence of uncertainties is improved. At first, the dynamic model of a quadrotor is introduced and descriptive equations are presented in an appropriate state-space in order to design a controller based on backstepping method. Then the backstepping controller is designed using virtual controller for trajectory tracking. In this control system, the control performance is not satisfying because of the physical uncertainties existed in quadrotor. Consequently, an online identification method is introduced and used to improve the performance of the controller. In this regard, some parameters, which are linear in the model structure, are identified by least square error technique and iterative least square method is used for identifying other parameters.The results indicate that the steady-state error is decreased and the ability of tracking of a desired trajectory in the presence of uncertainties is increased. Furthermore, the result demonstrate the stabilization of roll and pitch angles, while, the method prevents the vibration of control forces.
Volume 16, Issue 89 (7-2019)
Abstract
The aim of this study was to investigate the effect of ultrasound power at 40 to 80 percent (equal to 232-464 W), extraction temperature (50 to 80 °C) and extraction time (10 to 30 min) on the soluble polysaccharide extraction from the Pleurotus ostreatus. The response surface methodology using Box-Behnken design (with three variables, three levels and 5 replications at central point) was applied to optimize extraction conditions and evaluation of the effects of main factors and their interactions. Antioxidant activity (scavenging ability of OH and DPPH) of extracted polysaccharide were also evaluated. Optimization of polysaccharide extraction yield using response surface methodology indicated that combination of the ultrasonic power of 58.06 percent (~337 W), extraction temperature of 65.15 °C and extraction time of 21.72 min resulted in maximum extraction yield (17.71%). Among three independent variables, ultrasonic power had the highest and temperature had the lowest impact on the rate of extraction. The results from antioxidant activity evaluation showed that even though extracted polysaccharide had lower absorbance capacity of the free radicals in comparison with control samples (ascorbic acid and BHT), but it revealed an acceptable antioxidant property.
Volume 17, Issue 6 (8-2017)
Abstract
In this paper, reliability of missile system in its total life cycle is evaluated in terms of its subsystems’ reliability, using Continuous Time Markov Chains (CTMC) and Monte Carlo simulation method, finally results of both methods are compared. Missile system’s life cycle includes storage, pre-launch and operation states. Missile system is composed of variety of components and materials, hence different environmental conditions and various stresses imposed on missile system in each state during its life cycle, stimulates diverse failure modes and mechanisms. Therefore, failure probability distribution function differs for each subsystem in each state. Flight control, mechanical parts and equipment, engine and warhead are four main subsystems of the missile system. They are linked in series therefore each one’s failure will result in system’s failure. Exponential, Weibull, Lognormal and Gompertz distributions are used for subsystems’ modeling in different life cycle states. Unlike many other researches in this field, failure rates are time variant. System is supposed to be unrepairable during life cycle. Finally, Continuous Time Markov Chain’s superiority in comparison with Monte Carlo method, both in accuracy and required amount of calculations is demonstrated and a few suggestions, based on obtained results, are presented for system reliability improvement.
Volume 17, Issue 9 (11-2017)
Abstract
The system of compressible equations using upstream numerical methods has convergence problem to analyze low-Mach number flow. In this study precondition method is employed in Euler equations to solve convergence problem in low-Mach number flow and this preconditioned equations are used to analyze flow around a two-dimensional body. The preconditioner modifies the transient behavior of the Euler equations in manner that the stiffness of the eigenvalues is removed and allows for a faster convergence to the steady state. So, Turkel precondition method, one of the useful preconditioner matrices, is applied in system of Euler equations. As majority of solvers use conservative variables, precondition matrix is recalculated for conservative variables and is employed in Euler equations. The upstream finite volume Roe method in an unstructured grid is employed for space discretization of equations. Transient part of equations also is discretized with fourth order explicit Runge-Kutta method. The performance of the proposed approach is vetted through an inviscid tow-dimensional flow around the NACA0012 airfoil with different Mach number and the steady state solution is calculated. Numerical results show that Turkel preconditioner allow for a faster convergence to the steady state solution in low-Mach number. . .
Volume 21, Issue 151 (September 2024)
Abstract
The process of cheese production and ripening takes place with the help of an inclusive range of diverse and continuous biochemical reactions, which, if balanced, lead to the production of products with very desirable quality characteristics, including color and physicochemical properties. In this study, the kid goat and calf lipases at the levels of 0.1, 0.2, 0.3, and 0.4 g (per 100 Kg retentate) were used in the production of ultrufiltrated Iranian white cheeses. The effect of lipase treatment on color parameters (L*, a* and b* values) and some physicochemical properties (acidity, moisture, protein and fat) of the product were evaluated. The cheese sample without enzymatic treatment considered as control and its color and physicochemical properties was compared with other cheese samples during 90 days of storage period. Analysis of variance showed that the lipase enzyme significantly increased L* and b* index values of the cheese samples but it had not significant effect on the a* index. Furthermore, the time of storage caused a significant increase in these color parameters. Treatment with lipase and storage time had also significant effect on the physicochemical parameters. In general, by increasing the amount of lipase, and storage period, the amounts of acidity, moisture and protein increased and fat content decreased meaningfully. The results of this study revealed that by using 0.3-0.4 g lipase, particularly kid goat lipase, an ultrafiltrated Iranian white cheese with an acceptable quality can be produced.
Volume 21, Issue 156 (February 2025)
Abstract
The present study was conducted to investigating the effect of Persian gum (PG) and microbial transglutaminase (MTGase) on sensorial, color and microbial characteristics of ultrafiltrated semi-fat white cheese during 60 days of cold storage. In order to produce semi-fat cheeses, PG was used at three levels of 0, 0.25, and 0.5% and MTGase enzyme at three levels of 0, 0.5 and 1 unit/g of protein. The results revealed that the treatment of cheese samples with PG and MTGase enzyme had a positive effect on the sensory and quality characteristics of the product. In general, the cheese sample containing 0.5% PG and 0.5 units of MTGase enzyme attained the highest sensorial scores. Based on panelists’ preference, during the storage time, aroma and texture scores increased while color and appearance attributes decreased. The results obtained from the analysis of color values revealed that the lightness (L*) of cheeses increased with the addition of PG and MTGase enzyme treatment and decreased with the passage of storage time. Unlike the lightness, PG and MTGase enzyme had no significant effect on a* (red-green) and b* (yellow-blue) values of the experimented cheese samples. The results obtained from the microbial evaluation showed that the addition of PG increased the viability of lactic acid bacteria (LAB), but it had no effect on the count of mold and yeasts. On the other hand, increasing the concentration of the enzyme decreased the growth and survival of the studied microorganisms. The results of this study showed that PG can be used as a fat substitute along with MTGase enzyme to produce ultrafiltrated low-fat white cheese with favorable technological and sensory characteristics comparable to high-fat cheese varieties, and the best sample of ultrafiltrated semi-fat cheese is obtained using a treatment containing 0.5% PG and 0.5 unit of MTGase enzyme.Volume 22, Issue 3 (5-2022)
Abstract
The problem of determining the prestressing force in the tendons of prestressed concrete structures and monitoring the non-exceedance of prestressing drops is an issue that has been addressed by many researchers over the past decades and has provided methods in this field. Today, pre-installation sensors are installed in important prestressed concrete structures to monitor prestressing loss. However, due to the unpredictability of such equipment in older structures, monitoring of these forces requires destructive or non-destructive testing but is inaccurate. Therefore, in this paper, a method is presented that without the need for these sensors and destructive tests, only by measuring static displacement, is able to detect the amount of prestressing loss in the cross-sectional tendons of a prestressed concrete beam. In this regard, an algorithm in the Python program environment based on genetic algorithm as well as modeling in the finite element analysis program is provided. The numerical example presented in this research shows that the proposed algorithm detects the values of prestressing loss with good accuracy even in spite of 10% of the intentional error due to measurement. In recent years, the use of prestressing methods has become much simpler and more effective, and its materials have been optimized. Today, a high percentage of structures under construction worldwide are built using this technology, and the advance has found wide applications in the construction of office buildings, residential, commercial, parking lots, sports stadiums, concrete tanks and special structures such as piers. Therefore, in recent years, for long-term monitoring of prefabricated structures, equipment and sensors sensitive to force drop, such as fiber optic sensors and FBG sensors in the construction phase are predicted and installed in the desired locations. [13] However, since the above equipment requires a lot of money and it is not possible to use them in old structures, the need for a technique that shows the amount and location of force reduction in all tendons without using them remains. Therefore, in this paper, a method is presented that, while using the simplest tools, provides the most accurate results only by measuring static displacements under the effect of various loading scenarios and using an artificial intelligence algorithm based on genetic algorithm. The proposed method is based on computer analysis and comparison of the results of two prestressed concrete beams with the same geometry, loading and arrangement of tendons. First, a specific prestressing beam is modeled in the SAP2000 analysis program and the desired prestressing forces are applied to it, and then these forces are reduced in some of the studied tendons. This deliberate change in prestressing values is considered as failure and the technique presented in this mapping tries to discover the extent and location of failure of this beam. In other words, this paper is the determination of the amount of prestressing force in prestressed concrete beams in which force measuring sensors are not predicted without the need for destructive testing and only by measuring the static displacement under load. In the form of a numerical example on a prestressed concrete beam consisting of 6 steel tendons and using a genetic algorithm, it was shown that the displacement is a function of the amount of prestressing and its location and amount of reduction by the technique used. It was correctly detected with 93% accuracy when 10% of the deliberate error due to displacement field measurement was applied. As a suggestion for future work, this research will be able to be developed in the simultaneous diagnosis of prestressing reduction and beam concrete failure.