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Showing 31 results for Haghighat


Volume 0, Issue 0 (Articles accepted at the time of publication 2024)
Abstract

Urban landscape, as a narrative text, seeks to link social history to the arena of the city in urban open spaces. The interventions made in the environments over many years, which are manifested in the form of urban landscapes, etc., are actually new textual layers, that are the result of a relationships chain of companionship and succession in the primary text's narration. In all, there are traces of various signs related to different epochs related to the memories of the site, as well as, reception and understanding the narrative language of any urban landscape. The main question of this research is to discover the relationship between collective and individual memories with the reception of the urban landscape layers as a narrative text; and how to use these relationships in renovating the landscape in the historical urban sites.

This paper pursues the achievement of process in the reconstruction and reception of landscape in the historical sites based on the preservation of collective memories, and the Intertextuality theory as the main goal.

This qualitative research used the method of field study and semi-structured interviews with 32 citizens in the age range of 30 to 70 years of Isfahan city, and the results were analyzed with interpretative content analysis.

This study shows that in order to protect and strengthen the possibility of reception and understanding the narrative urbabn landscape as a text and the continuity of collective memories in historical sites, conserving and renovating strategies based on intertextual relations should be considered together.



Volume 2, Issue 1 (Issue 1 (Tome 2)- 2012)
Abstract

Garden city idea as an important idea had emerged on 19 century. Creating sustainable complexes and having more relationship with natural environment were the main goals which had been defined for this idea. This idea was established in urbanism literature by Howards' research about creating a balance between city and village living; whereas in east, Garden City as a pure idea has had a metaphysic meaning which is used to create earthy paradise since 16th century. Respect and reverence for water and trees is institutionalized in ancient civilizations of Iran. Iranian people respect trees and water, both separately and in composite forms as gardens, which have been a well-known cultural value both before and after Islam. The oldest Persian garden that have been discovered dates back to the Achaemenid Empire and the quadripartite gardens (charbagh) of Pasargadae. By studying about existent historic gardens, Persian Gardens are divided into different types. The way people use special physical and functional features could also be used as a scale of this division. In Persian Garden category, Garden City has been defined as a well-known model for designing particular gardens in city scale. According to this model, gardens have used sacred and soft spaces as a combination of hard and heavenly, for defining body structure and the development of the city textures. In advanced (pre- designed) samples, the entire city has been formed as a big garden; composed of a set of small gardens with many symbolic features, such as pavilions and water ponds, as seen in the Persian Charbagh Garden. During Safavid dynasty, Isfahan, as the largest Persian garden city, had been supported by a green major axis; which is the so called Charbagh that has been remained as a green heritage so far. Gardens and trees were the most important natural and architectural elements in Isfahan's cityscape at that period. These elements usually have been considered as the traditional identity of the garden city; hence their sustainability had a key role in preserving the structures. Therefore, Designers manufactured particular urban infrastructures to provide useful irrigation system. They had to construct the channels that branched off from the central river of Isfahan (Zayandehrood) and made the water accessible all around the city. First section of this paper is about Safavid Garden City origin. This subject was studied from the politics and governance points of views. In the following, Howard's Garden City origin has been studied. It has formed according to the special Utopias, which had relationships with that time's believes. In addition, some principles of Safavid Garden City have been compared to Howard's. The special study has been done about Intellectual origins which have influenced these Garden Cities creation. In conclusion, the comparison of Howard and Safavid Garden Cities shows that these ideas had been developed based on the worldview and vision of creative Iranians during Safavid dynasty and in 19th century. Moreover, the special methods of plantation, the quality of social relationships and economic similarities were the main differences between these two Garden Cities.

Volume 3, Issue 1 (spring 2022)
Abstract


 Statement of Problem: Rural landscapes, as continuing cultural landscapes, represent the natural personality of their community over time, landscapes that change under the influence of cultural and natural currents in their context. Human interaction with nature and the continuity of these landscapes have created several outstanding values in rural landscapes that express tangible and intangible values or in other words, its semantic importance. International documents emphasize the need to develop a conceptual framework and identify these values as a key component in the process of conservation of these landscapes, so that any effort to protect and regenerate rural landscapes, in principle, helps to preserve culture and sustainability of a land.
Aims: To identify and categorize the values of rural landscapes in order to regenerate and sustainably protect such environments and transfer their collective knowledge and cultural meanings to future generations.
Methods: This research first defines the concept of cultural landscape and formulates the conceptual framework and position of rural landscape by reviewing international documents and conventions and examining the views of experts. Then, according to the studies, the values in rural landscapes are classified and explained and finally, a model for regenerating and preserving rural landscapes is presented.
Findings: In this study, the values of rural landscapes divided into two groups: natural and tangible values ​​and cultural and intangible values. Natural and tangible values ​​including environmental, physical, economic and educational values, ​​and cultural and intangibles values include cultural, spiritual, social, and recreational ones. Although in some cases, values ​​are a combination of both, so they are very difficult to refine.
Results: Considering the existing values, a model for recreating and protecting rural landscapes has been presented, which in order to coordinate with the change in the prioritization of these values, it is necessary to pay more attention to their dynamic and multifunctional aspects.

Volume 3, Issue 2 (summer 2022)
Abstract

Objectives: In recent years, the study of the concepts of resilience in different urban areas at different scales has attracted special attention, although the level and number of these studies are very small. Especially in the city of Tehran, which has entered the modern period from traditionl period ,the issue can be considered.
Methods: in the current research , first through library studies in the filed, items related to physical , environmental and social resilience in residential complexes were extracted.then, in these complexes, there are many modes of this type of resilience , which can be achieved by studying and classifying them to the degree of desirability of these complexes. the case study ,studied in this research is kOI No bonyad residential complex, because it is very popular despite the fact that it was built a long time ago .this research is done with interpretive method and in the form of qualitative and quantitative analysis. questionnaire, which was distributed among the residents of this complex to measure the level of physical -environmental and social resilience.
finding: from the findings of this research , it can be seen tha ASP foundation complex(ASP towers)has high level of resilience despite its high construction year.
conclusion: with the investigation done, the patterns used in the complex, which caused its durability , popularity and high resilience , can be used in the design of modern residential complexes so that we can have lasting buildings.

Volume 4, Issue 4 (winter 2024)
Abstract

Problem: The problem addressed in this research is the potential conflict between economic goals in urban branding and the long-term health of urban ecosystems. Specifically, there is concern that focusing solely on economic aspects in urban design may jeopardize the health of the urban ecosystem and lead to severe damage over time.
Target: The primary objective of this research is to develop an urban brand that prioritizes sustainability and enhances the health of the ecosystem within cities. The aim is to provide solutions for maintaining and strengthening social and environmental interactions through landscape design in urban green infrastructures.
Method: The research adopts an applicable-science approach with a descriptive-analytical method. Data collection is primarily library-based, focusing on gathering information about urban green infrastructure, particularly paths and spaces, and their role in fostering sustainability and social and environmental interactions.
Result: Based on the collected information, the research identifies the key components and principles of urban green infrastructure. The two major components are paths and spaces, which form the structure of green infrastructure. Additionally, the research outlines principles such as multi-functionality, communication, synchronization, process-oriented design, and strategic planning as fundamental to the development of sustainable urban branding through landscape design.




Volume 6, Issue 1 (7-2016)
Abstract

In today's highly competitive conditions to maintain and expand market share is the result of brand performance. Suppliers to maintain and improve its position against competitors must pay attention to branding and brand management.Therefore, identifying of factors influencing brand performance is an important issue in the implementation of marketing strategies.In this article, the researchers explore to thisquestion: What factors influencing on brand performance? This study discusses variables from customers’ viewpoints by taking the sample of industrial purchasersand buying center of experts from manufacturers of home appliances in Tehran.106analyzed questionnaires from buying center was presented to. PLS software was used to test hypotheses.The results of the data analysis confirmed that all of theHypothesis.Research Results indicate thatsupplier social responsibility, reputation, B2B brand equity, brand preference and purchasing repeat and loyalty intentions havesignificant and positive effect on brand performance. Relationships reputationand social responsibility on B2B brand equity;social responsibility and reputation;B2B brand equity and brand preference; brand preference and purchasing repeat intentions was significant positively. Internal Suppliers can use the researchfindings to branding and brand performance management in internal and externalindustrial markets.

Volume 7, Issue 4 (2017 2018)
Abstract

Iran has an arid climate which characterized by long, hot, dry summers and short, cool winters. Therefore, sunlight and its heating effects were important factors of Iranian architecture and gardens structural design. Textures and shapes were selected by architects to harness the light and supply a shadow in the summer.
Water is very important in this climate, both in the architectural design and longevity of gardens. In addition to water, the plants in Iran had been particularly significant. In ancient civilization of Iran, plants have had special position. Supernatural powers that had been in trees such as life-giving, young giving, productivity and Immortality made them sacred for Ancient Iranian people. However, attending to supernatural power of plants was the importance reason that people regarded to plants and made some symbols such as “Life Tree” has income. In Zoroastrian religion books, more values have said about Supernatural cost of plants. Plants have a special value in Zoroastrian Fire Temples, religious ceremony and routine life. Therefore, garden and gardening were sacred for Iranian. The term Zoroastrianism is, in general usage, essentially synonymous with Mazdaism, have discovered dependent on Achaemenids Empire (559–330 BC) and there were in Pasargad. In the Islam tradition the garden as Paradise is, perhaps, even stronger, since the Quran (the central religious text of Islam) describes Heaven as a garden. Islam was spread to the Persians, and reciprocally the Muslims adopted the Persian style of garden. Therefore garden has been invaluable to Iranians. Persian Garden includes some types which one them is Garden City.
Isfahan as the Capital of Safavid Dynasty has designed as a big garden according garden city model. Therefore, some solutions have used in urban design regarding Isfahan's arid climate. Safavid government followed the realization of cities ideal that rooted in Islamic beliefs and opinions. The investigations in historical perspective of Safavid cities indicates the importance of cities as the place for presence of symbols and signs. The Symbols which has remind as the ideological concepts, power of dominating government and also getting identity to the city.
During the history of Safavid urban design, there were some direct and wide streets (Charbagh) which were the main factors of development and improvement of cities among urban functional and symbolic elements. In historical background of Isfahan garden city is pointed to construction of street (Charbagh) which has attracted the European tourists attention and it will investigate in this article.
Initial section of this article is allocated to explain about historical background of Isfahan city in Safavid era and also Charbagh Street. Then this paper with emphasis on some historical documents and analytical studies, compares the Isfahan Charbagh Street with its similar sample in France (Champs-Elysées Street). The conclusion of this article indicates the similarity of Isfahan Charbagh Street and Champs-Elysées Street in some skeletal specifications and the way of formation. French Boulevards were constructed after Isfahan Charbagh in terms of time and they were formed after publishing itineraries and pictures of tourists from this place in Europe .

Volume 9, Issue 1 (Spring 2019)
Abstract

Some semi-closed or completely abandoned big sites found in cities which caused several urban problems in the vicinity of urban residential areas such as Environmental issues and visual pollutions of urban landscapes. Today Reclamation of this group of all kinds of urban landscapes with regard to their historical, identities and industrial heritage values is the major goal of planners, designers, and Landscape Architects. This article also emphasizes on this main goal.
The main issue of this research is how to reclaim post-industrial landscapes with the feature of enhancing the pleasant components as an effective factor in improving the quality of the place. Toward this goal by means of the analytical-descriptive research method and by using library and field research methods for data collection (i.e. interview with the expert elites) and international declarations of ICCOMOS and TICCIH, we extract the concepts relevant to post-industrial Landscapes and the factors influencing the sense of Pleasure on citizens.
The proper recognition of the approaches and policies of reclamation of post-industrial sites, along with the proper use of the potential of post-industrial landscapes to increase citizens’ sense of pleasure, are the most important findings of this paper.
The results of this essay are macro policies which can lead to sustaining Pleasure in citizens at the reclamation of post-industrial landscape process. To narrow the subject, the mentioned policies were evaluated through asking elite interviewees. Finally, a comprehensive model is presented in order to Reclamation of post-industrial landscapes with an aim of improving Pleasure in urban landscapes.



Volume 9, Issue 3 (Summer 2018)
Abstract

Aims: Nitric oxide (NO) plays an important role in maintaining cellular stem status, and the range of electromagnetic fields (EMF) is very deep in contrast to the electric field. The aim of this study was to investigate the effect of electromagnetic field and nitric oxide on the neural differentiation proteins marker and viability of the rat bone marrow mesenchymal stem cells.
Materials and Methods: The present experimental research was conducted on bone marrow mesenchymal stem cells of Vistar rats. For treatments of the cells, high (1mM) and low (10micromolar Deta-NO) concentrations were used as a nitric oxide donor molecule and 50Hz low-frequency electromagnetic field and they were compare with the control group. The cell viability was recorded by MTT assay test, the neural differentiation pathway gene expression was investigated by RT-PCR technique, and the neural differentiation marker protein expression was evaluated by Immunocytochemistry technique. The data were analyzed by one-way ANOVA, using SPSS 13 software.
Findings: After 24 hours of treatment with nitric oxide and EMF, the rate of viability in all groups was significantly decreased compared to the control group. After 48 hours, EMF alone, as well as with low concentration of nitric oxide did not decrease the rate of viability and cell growth increased compared to the control group. In the group treated with high nitric oxide concentration along with EMF, MAP2 protein was expressed in the number of cells more than the control group and the one treated with EMF.
Conclusion: The electromagnetic field, along with its high concentration of nitric oxide, decreases the number of rat bone marrow mesenchymal stem cells and, by increasing cell size, gene expression and neural differentiation proteins marker facilitates their differentiation to nerve-like cells.
 


Volume 10, Issue 1 (2-2025)
Abstract

Aims: Diabetic Neuropathy Pain (DNP) is a chronic condition that arises from nerve damage caused by prolonged hyperglycemia. It leads to burning, tingling, and sharp pain, primarily in the extremities. This study examines the effectiveness of Cognitive-Behavioral Therapy (CBT) in mitigating recurrent negative thoughts, reducing anxiety sensitivity, and enhancing emotional adjustment in individuals with DNP.
Method and Materials: The study employed a quasi-experimental pre-test-post-test design with a control group, involving 36 patients with DNP from Ardabil clinics located in Ardabil, Iran in 2024. Patients were purposively sampled and randomly assigned to intervention (n = 18) and control (n = 18) groups. The intervention group underwent eight 90-minute CBT sessions, while the control group received no intervention. Data were gathered using the Repetitive Negative Thinking Questionnaire, Anxiety Sensitivity Index-3, and Emotional Adjustment Measure. The collected data were analyzed using MANCOVA in SPSS-27.
Findings: The results demonstrated that CBT significantly improves emotional adjustment (F = 49.46) and reduces recurrent negative thoughts (F = 45.41), as well as physical (F = 52.27), cognitive (F = 59.61), and social dimensions of anxiety sensitivity (F = 38.34) in individuals with DNP (P < 0.001).
Conclusion: The findings highlight CBT's transformative impact on the psychological resilience of DNP patients, fostering adaptive emotional regulation and diminishing maladaptive thought patterns. By addressing the interconnected dimensions of anxiety sensitivity and emotional adjustment, CBT offers a pathway to holistic pain management, emphasizing its potential as a cornerstone in the psychological care of chronic pain conditions.


 

Volume 10, Issue 4 (winter 2021)
Abstract

Aims: The overall purpose of the current study is to read the spiritual contexts of the resurrection in the revival of the monumental and narrative perspective of abandoned in inner-city cemeteries. It has emphasized on the Quranic teachings and narrations of the infallible Imams in this study.
Instruments & Methods: This study has been conducted a descriptive-analytical method and using Library and field method (Question from the professional experts in the fieldes of religious and landscape architecture) to gather information. The issue of resurrection has been explained in accordance with the interpretations of the Holy Quran and Hadiths and the views of philosophers, mystics. Reviewed Also how to use the objective and mental codes of resurrection according to Quranic verses in the perspective of abandoned cemeteries in the city.
Findings: The relationship among the location's components, landscape, and semantics in the historic cemeteries landscape reading and perception is the most important finding in this study. The findings emphasize resurrection in accordance with the interpretations of the Holy Quran and hadiths and the views of philosophers, mystics.
Conclusion: The conclusion shows, in reviving the abandoned inner-city cemeteries landscapes, the concept of resurrection can lead citizens and visitors to a better understanding of death narration and its remembrance in the minds. It will also help to connect them more with landscape and reinforce place attachment.


Volume 10, Issue 4 (Fall 2024)
Abstract

Background: Viral infections may play a significant role in the development of heart failure, especially in people with related cardiac conditions such as myocarditis. Hepatitis B and D viruses (HBV-HDV) are potentially fatal liver infections. This study examined the influence of metabolic syndrome and its associated disorders.
Materials & Methods: This cross-sectional study investigated hepatitis D antibody and hepatitis B surface antigen (HBsAg) in 239 people aged 35 to 65 years in Mashhad, Khorasan Razavi Province, Iran in 2018-2019. There were two study groups: those with cardiovascular diseases (CVD) and healthy individuals. Serum samples of all subjects in both groups were examined using enzyme-linked immunosorbent assay (ELISA).
Findings: HDV infection was detected in none of the study groups. Only one patient (0.8%) in the case group tested positive for HBsAg. The average LDL (low-density lipoprotein) (p= .8) and cholesterol (p= .3) levels in terms of lipid profiles were similar in both groups. Although the mean high-density lipoprotein (HDL) level in the patient group was lower, the mean triglyceride level in this group was higher than in the control group. Fasting blood sugar (FBS) (p= .009) and aspartate aminotransferase (AST) levels were significantly higher in CVD patients, while 59.3% of them exhibited metabolic syndrome.
Conclusion: This study results demonstrate no connection between HBV/HDV infection and cardiovascular diseases. The findings confirm that metabolic syndrome and hyperglycemia are underlying factors in cardiovascular diseases. Changes in HDL and triglyceride levels could impact cardiovascular diseases more than other lipids.


Volume 11, Issue 4 (Winter 2022)
Abstract

Aims:
It is to achieve practical criteria for designing and improving the quality of social behavior settings in accordance with the spatial qualitative values of social behavior settings in neighborhood parks and considering the components affecting the quality of the behavior settings with a holistic approach (objective-subjective) which include objective and subjective criteria which lack of proper attention to them, overshadows the overall function of the park spaces. Based on the Persian garden lessons, it can strengthen social interactions.
Methods:
This study was based on fieldwork with an analytical-descriptive approach. Quantitative analysis tools of indicators include questionnaires and cognitive maps to examine objective and subjective criteria from the landscaping perspective in behavior settings and the objective quality of space is evaluated by the syntactic indicators of space syntax.
Findings:
Findings indicate that among the objective criteria of place in behavior settings of neighborhood parks in the 5th district of Tehran, safety and social activities and also among the subjective components of place, security and sociability in the physical quality of the park have higher priority.
Conclusion:
The results show that People use spatial places that are designed openly and adjacent to active social settings as subjective settings without regard to physical values. Numerical intervals obtained from modeling in the depthmap show the attention of designers to the shape of ground in the design of park and lack of attention to spatial quality of behavioral settings, which is directly related to security and sociability of the park.

Volume 13, Issue 1 (3-2022)
Abstract

Abstract
Introduction: Cervical cancer is the fourth most common cancer among women. In recent years, attention has increased to natural products such as curcumin with anti-cancer potential as a therapeutic supplement. However, due to its poor solubility, its clinical use is limited. In this regard, in this study, to improve clinical parameters, the effects of nanocurcumin on the angiogenesis inhibition of cervical cancer were investigated and compared with free curcumin.
Materials and Methods: MTT method was used to evaluate the proliferation of the HeLa cell line with free curcumin and nanocurcumin at different doses and time intervals and the rate of apoptosis was assessed by flow cytometry. Then, the expression of the vascular endothelial growth factor (VEGF-A) gene in HeLa cells was measured by Real-Time PCR and Western blotting, respectively.
Results: According to IC50 for 48 hours in the HeLa cell line, which was 15 μM/ml and 50 μM/ml for nanocurcumin and free curcumin, respectively, the nanocurcumin showed a greater lethal effect. VEGF-A gene expression (p <0.0001) and protein level (p <0.01) were significantly lower following nano-curcumin treatment than free curcumin.
Conclusion: Nanocarrier increased the solubility and further inhibited the proliferation of cervical cancer HeLa cells and was three times more effective than curcumin in inhibiting angiogenesis at the same concentration. Therefore, nanocurcumin can be a good option for drug supplementation along with routine cervical cancer treatment.
Keywords: Cervical cancer, Nanocurcumin, HeLa cell, VEGF-A.

Volume 13, Issue 3 (Fall 2023)
Abstract

Aims: This paper aims to find a comprehensive conceptual model for health landscape by reviewing some important and decisive theories on the relationship between landscape and health.   

Methodology: The theories in the field of health landscape are analyzed based on a descriptive-analytical method in two categories. The first category examines the existing mechanisms explaining the relationship between landscape and health and why the landscape affects people's health, while the second category tries to measure these effects by examining the quantitative and qualitative dimensions of the landscapes.

Findings: The analyses showed that the related theories in this field, which were initially formed based on a purely objective or subjective, gradually and in the course of their evolution, somehow converged with the comprehensive and holistic concept of landscape and focused on both aspects of objectivity and subjectivity in analyzing the health landscape. This has led to an approach in the field of landscape that emphasizes the role of the individual, society and the environment, considering the health of the landscape as a relative matter that will vary from person to person.

Conclusion: The presence of individual agency (adaptive skills and capacities of a person) and socio-environmental dimensions in today's definition of health in other fields indicates the existence of an interdisciplinary agreement on this convergence. This article shows that by relying on perception, these seemingly opposite aspects can be put together and a meaningful and holistic model can be achieved in relation to the health landscape.
 

Volume 13, Issue 55 (9-2015)
Abstract

  In this research, physicochemical properties and oxidative stability of Roghani virgin olive oil grown in two regions of Roodbar and Kazeroon, located in north and south of Iran respectively, with differences in pedoclimatic conditions, altitude and soil were investigated. To determine the physicochemical properties, acidity, peroxide value, spectrophotometric indexes at 232 and 270 nm, smoke point, specific gravity and refractive index as well as the total contents of phenolic compounds, alpha tocopherol, chlorophyll, carotenoid, and fatty acid composition were evaluated. To evaluate the oxidative stability, the effect of heat treatment at 180 °C for 8 hours on indicators such as conjugated diene value, carbonyl value, polar compounds and oxidative stability index were tested. Results indicated the differences in the structural properties and oxidative stability of the oil obtained from two regions. As the oil from Roodbar region with lower altitude, lower average annual temperature, higher average annual rainfall, and specific geographical conditions, contain higher phenolic compounds, alpha tocopherol and oleic acid and also showed higher oxidative stability during heat treatment. But the oil of Kazeroon region with higher altitude, higher average annual temperature, and lower average annual rainfall, had higher linoleic and linolenic acids and exhibited lower oxidative stability during thermal treatment. Therefore the results of this study can be used as a description of physicochemical properties and oxidative stability of Roghani olive oil from two regions of Roodbar and Kazeroon.  

Volume 15, Issue 3 (5-2015)
Abstract

In the present paper, drawing process of metal plates through a wedge-shaped die, by proposing new velocity field, has been analyzed by upper bound method and simulated by finite element method (Abaqus software). Among the important cases in upper bound analysis of the forming processes is selection the appropriate boundaries for the deformation zone and offering admissible velocity field that in addition to satisfy the incompressibility condition and boundary conditions, is consistent by the behavior of metal flow in the deformation zone. The entrance boundary of deformation zone has been assumed exponential curve surface and boundary at exit has been assumed cylindrical surface. In the past analyses, metal flow lines in the deformation zone have been assumed straight but in reality it is not. In the present work, velocity field and also geometric shape of the deformation zone, justify that metal flow lines are non-straight. Base on proposed velocity field, internal powers, shear and frictional and also total power have been calculated. Then, according to the plate pulling velocity, required drawing force has been obtained. Finally, analytical results have been compared with the obtained results of FEM. In order to validate the present analysis, obtained results have been compared with other researchers. Also, the effect of various parameters, such as percentage reduction in thickness and shear friction constant on the drawing force and die optimum angle have been investigated.

Volume 16, Issue 4 (6-2016)
Abstract

In this paper, the drawing process of the sheet metal through the wedge shaped die has been analyzed by upper bound method using stream function. First, a new deformation model has been introduced in which inlet and outlet shear boundaries are considered flexible. Then, the optimized geometry of the deformation zone has been determined through the effect of work hardening of the sheet material depending on the process conditions. According to the suggested stream function, velocity field, strain rates and power terms have been calculated. The analytical results have been compared with the results of the published analytical data and the finite element simulation results. Furthermore, the effect of work hardening exponent has been investigated on the deformation zone, drawing force and optimum die angle. It has been shown that by increasing the work hardening exponent, inlet and outlet shear boundaries of deformation zone are being inclined to the inlet zone of the die and the required drawing stress is decreased. In addition, by increasing the friction factor, inlet and outlet shear boundaries are being inclined to outlet zone of the die, and by increasing reduction in thickness, inlet and outlet shear boundaries of deformation zone are being inclined to the inlet zone of the die. It is shown that the analytical results have been improved up to ten percent in comparison to the published data.

Volume 17, Issue 11 (1-2018)
Abstract

This paper attempts to predict the occurrence of central bursting defects in the plane strain extrusion process using upper bound method. For this purpose, the material under deformation is divided into three deformation zones. These deformation zones are separated from each other by the shear boundaries as the exponential functions. Then, an admissible velocity field, including the radial and the angular velocity components are developed for each deformation zone. Strain rates components are determined and mathematical relationships for internal, shear and friction powers are obtained. For a given process conditions, the total power toward geometrical shape of shear boundaries entrance and existence is optimized. Intersection position of the entrance and existence shear boundaries of deformation zone on centerline represents the occurrence of central bursting defects. The effect of process parameters, including semi die angle, reduction in area and friction factor on the defects and the extrusion force are investigated. The analysis results with the FEM simulation (Deform software) and the results of the published papers are compared. The results showed that increase of friction factor and increase the reduction in area decreases the probability of central bursting defects.
Ali Haghighat, Hamed Vahdati Nasab, Ali Reza Hejebri Nobari, Seyyed Mehdi Mousavi Kouhpar,
Volume 19, Issue 3 (7-2012)
Abstract

An amalgamation of ancient mythological and linguistic features from Ghabrestan Tepe, this article is disposed to introduce some of the oldest findings especially about the then prevailing myths. It can possibly be said that the oldest motifs carved by men, on bones, stones or on cave walls have been the depictions of myths related to Homo sapiens; however, even after the lapse of thousands of years, it is still impossible to find the main tenets they actually tried to narrate through those depictions. Unfortunately, we have to admit that, even the use of modern methods, doesn’t help us to reach to those stories that are much warped and deformed. This article, tries to carry, what has remained from some later version of the myths, backwards in time and, by focusing on a pottery design, uncover what once has been a mythological and significant narrative. Perhaps this had been a well-known mythological story narrated in religious and domestic circles.    

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