Showing 55 results for سیر
Volume 19, Issue 3 (Fall 2015)
Abstract
Abstract This research aims to experiment a quantitative method in urban form studies with a typomorphological approach .This method is originally based on physical density with its more reliable description as a measurable indicator. In this paper after the introduction and a brief look at some former quantitative approaches to urban form through the theoretical framework ; and also the relationship between density and architectural-urban typomorphology , a method (or tool) called the "spacemate" is described in a rather detailed manner .As the case study of this research, some samples from the urban tissues of Tabriz metropolis were chosen to be analyzed with this method. The basic data was then collected and classified ,and the results were placed and reflected on the "spacemate" in order to be analyzed at the final step. Although at the first place this tool is originally designed to be applied as a tool for studying and analyzing the urban forms in the western cities and towns ,and has been examined in a limited scale, but the results of this research (which is the first of its kind in Iran) show that it is also applicable in studying many aspects of urban forms -both descriptively and anticipatively-in Iranian cities, as well as many other urban textures in other similar countries, in presence of sufficient and reliable data.
Volume 19, Issue 6 (12-2019)
Abstract
Buckling of thin-walled structures is an important issue. Thin wall shells have many applications. The refinement of fuel and fluid storage tanks is very valuable. The important points of the thin-walled cylindrical shells are the little thickness of the shell relative to the other dimensions of these structures. This feature places the instability issue as a determining factor in the behavior of these structures. Due to the low thickness and compressive strength of the field, the forces on the shell of these structures are more likely to be buckling. Researchers have always tried to increase the buckling strength of thin-walled cylindrical shells by recognizing the behavior of different types of materials and their geometry types, thus maximizing the use of existing structures. The conventional method is to use steel rings to retrofit steel cylindrical shells. However, the use of this method according to the conditions of the workshop and that the structure may be load-bearing and carrying flammable liquids is due to the use of welding with fire hazards and practically there will be no use of this method in these structures. So according to the above topic, in this research, the benefits of using CFRP as new materials have been considered. In this paper CFRP rings are used to replace steel reinforcement rings. Here, the use of these materials has been investigated for the reinforcement of thin-walled cylindrical shells under uniform lateral pressure. This type of loading is generally caused by the discharging of cylindrical shells and reservoirs. In this paper, CFRP rings were used as reinforcement against the buckling of thin-walled steel cylindrical shells and at certain locations at shell height. Five specimens have been manufactured and used for testing. The first experimental specimen is without ring reinforcement. The second and third specimens have a reinforcing ring in the middle of specimen high. The number of CFRP layers in the XC2 specimen is half the XC3 specimen. The fourth and fifth specimens have two reinforcing rings in one third and two-thirds of the height of the specimens. The number of CFRP layers is based on the results obtained from the nonlinear numerical analysis. The number of layers is chosen so to stop CFRP ring buckling. The external uniform pressure is used as specimens loading by employing a vacuum pump. ABAQUS software has been used for nonlinear analysis. The results of the experiments show that the CFRP rings greatly increase the buckling and post-buckling strength of the thin-walled shells. Therefore, the use of CFRP rings is being proposed as an alternative method for the reinforcement of these structures. experimental results show that the XC5 specimen, which has two CFRP rings, has the highest buckling strength compared to other specimens. The results show that buckling strength of cylindrical shells increases with increasing number of rings and number of layers. In this research, theoretical relations, as well as the code relations of the United Kingdom and the European :union:, have been used to assess the obtained results and a good agreement achieved.
Volume 20, Issue 1 (Spring 2016)
Abstract
Strategic Planning for Tourism Development in Yazd City, Using Meta-SWOT Model Abstract Satrategic planning is an approchfor management to do better and for get aimes. Thus strategic planning can use in tourism management. Touris strategy is in the core of tourism scince such as other activities.in thise regard SWOT model used fof strategic planning in tourism planning. Today with assessment of SWOT model understood that is qualified and haven’t predicat potaintial, thuse SWOT can supersed with Meta-SWOT. Formation of thise model has seven stepes that any step has seven steps. The purpose of this paper is to make brainstorm and ranking of decisions. Because of individuals changes your decision in during of activities, this tool can review input unbounded. This research is for tourism development in Yazd city and introduces Meta-SWOT for the first time.the methodology of this research is descriptive and analytical and data collection methods are documentary and survey. The results show that political stability is the main reseon for tourism development in Yazd city, and the other factor for tourism development in Yazd city are: economics constrains, note autthurities, human power and investment in tourism plans. The economics constrains for development of tourism in Yazd city depend on industries, legal restrictions and monetrary and currency problems. Key Word: Strategic Planning, Urban Tourism, Meta-SWOT, Yazd City.
Volume 20, Issue 1 (Spring 2020 2020)
Abstract
Expansion, utilization and distribution of potential economic opportunities among people have important impacts on the prosperity of each country. Simon Kuznets was the first researcher who systematically examined the relationship between economic growth and income distribution based on the statistical data. According to Kuznets, income inequality will decrease by economic growth in the long term. Therefore, economists focused on economic growth in order to reduce income inequality. However, the Kuznets hypothesis was faced with a serious challenge by publication of Piketty's “Capital” in the twenty-first century. Since, according to Piketty, not only income inequality has not diminished, but also it has increased unprecedentedly in the advanced stages of economic growth and development. In this regard, the aim of this study is to investigate the Thomas Piketty's hypothesis based on the statistical evidence of Iran by using the ARDL econometric method during the period 1975-2015. The results confirm Thomas Piketty's hypothesis according to statistical evidence of Iran. In addition, the effect of non-oil GDP on income inequality is negative and significant, but the impact of oil revenues is positive and significant. War has also led to increased income inequality.
Masoumeh Yousefi, Mahsa Tabari, Hamid Tavakolipour, Sirous Bidarigh,
Volume 20, Issue 139 (September 2023)
Abstract
In this study, the effect of nanoparticles on oxide at three levels of 1, 3 and 5% was added to polylactic acid and chitosan nanocomposites and the results of its SEM (electron microscope) evaluation were evaluated and showed films containing polylactic acid and chitosan. It had an irregular and compact structure and with the addition of nanoparticles on oxide, it had a regular and cohesive structure. And water vapor permeability showed a significant effect (P <0.05). The results of histometry showed that with increasing the concentration of nanoparticles, the tensile strength of the film and the nanocomposite coating was significantly lower than the control treatment (P <0.05). Also, large changes in length to break point did not show a statistically significant difference. The results of tissue stiffness of this study also showed that during the 15-day storage time, the test treatment had the highest amount of stiffness. The effect of film and coating of nanocomposites based on polylactic acid and chitosan containing nanoparticles on zinc oxide on microbial properties indicated that during the shelf life of bread containing polylactic acid and chitosan dimers has an inhibitory effect on fungal growth by increasing nanoparticles on zinc oxide. Increases significantly. It also showed that the shelf life of seven sliced toast containing the mentioned variables was higher at 5% level compared to the control treatment.
Mohammadjavad Morshedhassan, Shabnam Hamzeh, Zahra Siyar,
Volume 20, Issue 143 (January 2023)
Abstract
Phase separation and cocoa precipitation at the bottom of the bottle of cocoa milk is unpleasant from the consumer's point of view. Usually the amount of cocoa particles precipitate at the bottom of the bottle is of most importance. The aim of this research was to investigate the effect of five levels of stabilizers including: xanthan, κ‐carrageenan and mono-diglyceride on the sensory and physicochemical characteristics of cocoa milk using the response surface method (RSM). Therefore, 20 treatments were produced in three blocks with six replications at the central point, then physicochemical properties and sensory evaluation tests were performed. Numerical optimization method has been applied to produce optimal cocoa milk with a suitable viscosity of 110 centipoise and the lowest amount of phase separation and precipitation. The suggested samples of the software were compared in the production laboratory with the real results of cocoa milk with a one-sample T-test software at a 95% confidence level, which confirmed the correctness of the predicted model due to the absence of significant differences. Based on the results, it was found that the increase of hydrocolloids caused an increase in viscosity as a confidence level (p<0.001), as well as an increase in product stability and a decrease in the amount of sediment formation. Sensory evaluation showed that κ‐carrageenan had the greatest effect on overall acceptance, followed by xanthan and mono-diglyceride (p<0.001).
Volume 21, Issue 1 (Spring 2018)
Abstract
Aims: Exercise activity and the use of herbal supplements are effective in regulating vascular contraction by influencing on angiogenesis factors. The purpose of this study was to investigate the effect of caffeine and genistein supplement on cardiac levels of nitric oxide (NO) and vascular endothelial growth factor (VEGF) in wistar rats, following an acute swimming exercise.
Materials and Methods: In this experimental study, 49 male Wistar 8-10-week rats were randomly divided into 7 groups of control, saline, acute exercise, caffeine, genistein, acute swimming exercise plus caffeine, and acute swimming exercises plus genistein (7 rats in each group). Acute exercise included 90 minutes swimming. Dietary supplement groups, taked the caffeine at a rate of 5mg/kg of body weight by gavage and Genistein in the amount of 100mg/kg of body weight by intra peritoneal injection. Two hours after the end of the training session, the levels of NO and VEGF were measured by ELISA. Data were analyzed by SPSS 20 software using one-way ANOVA.
Findings: 90 minutes swimming exercise caused a significant increase in cardiac levels of NO and VEGF in acute exercise, acute exercise plus caffeine, acute exercise plus genistein in comparison to the control and saline groups (p=0.01), while supplementation of caffeine or genistein alone did not significantly increase the levels of cardiac level of these factors compared to control and saline groups.
Conclusion: The supplementation of caffeine and genistein increases the levels of NO and VEGF of the heart tissue of rats following an acute swimming session.
Volume 21, Issue 3 (Fall 2018)
Abstract
Aims: Vascular disorder is one of the consequences of diabetes. Physical activity also plays an important role in the improvement of this disorder. Therefore, the aim of this study was to investigate the effect of vigorous aerobic training on serum levels of inhibitory and excitatory factors of Angiogenesis in women with type 2 diabetes.
Materials and Methods: In this quasi-experimental study with pre-test and post-test design that was performed among women with diabetes population in Gorgan in volunteer sampling, 28 women with type 2 diabetes in Gorgan were selected By … sampling method and were divided into training and control groups (14 individuals each group). Training intervention consisted 8 weeks of vigorous aerobic exercise (70%-80%) with 3 times per week. Just before the exercise and 48 hours after that, serum levels of Nitric Oxide (NO), Vascular Endothelial Growth Factor (VEGF), and Endostatin (ES) were evaluated. The data were analyzed by SPSS24 software, using repeated measures ANOVA..
Findings: Eight weeks of aerobic training caused a significant increase in serum levels of NO (p=0.016), VEGF (p=0.036), and an insignificant increase in ES (p=0.237). Also, a significant decrease was observed in fasting blood glucose (p=0.027) and A1C (p=0.003) compared to the control group.
Conclusion: Regular aerobic exercise improves serum levels of angiogenesis-related and metabolic factors in women with type 2 diabetes.
Volume 22, Issue 3 (7-2015)
Abstract
Jihadi management is a set of features along with managerial scientific structure and revolutionary and Velayati values to make a very strong driving force for the country to pass crises. Concerning its importance, present paper identifies the traits of Jihadi management in improving managers’ performance.
Current study is a survey for which a questionnaire is used to gather data. To realize research aims, 384 middle and operational managers in companies and organizations in Tehran were considered as sample. Structural equation modeling (SEM) and confirmatory factors analysis (CFA) as well as LISREL and SPSS software packages were used to analyze data and to test research hypotheses and model. Research findings indicate significant impact by Jihadi traits such as “managers’ strong and good associations with employees”, “managers’ accountability and responsibility”, “obligation to commitments” , “authentication in affairs”, “designations” and “meritocracy” on managers’ performance.
Volume 22, Issue 3 (Fall 2018)
Abstract
Introduction
According to the World Bank (2016), more than 46% of the world's population (3.9 billion) live in rural areas. Predicted that by 2050 this number is reduced to 34%. The most important reason for this is rural migration to urban areas, seeking better quality of life, the existence of regional inequalities, and rural deprivation. Therefore, in order to prevent rural immigration and promote rural development, reducing deprivation and identifying its indicators as a principle for policy makers should be prioritized. These indicators are important for identifying the patterns of economic and social inequality in societies. For this reason, measures have been taken by countries to identify these indicators. The city of Poledokhtar is one of the areas with a rural population above the national average. The villages of this city are among the most deprived areas of Lorestan province. Barriers and limitations in quality of life, income sources, poor housing conditions, inadequate education, and lack of sanitation and social services for rural residents have led a large number of households to migrate from rural to urban areas to achieve better quality of life. On the other hand, it is necessary to identify the indices of deprivation in rural areas and present suitable solutions to it, implementation of deprivation and rural development programs, especially in the economic dimension and sustainable livelihood of rural households. Therefore, the present research attempts to analyze the regional deprivation indices in Poledokhtar. The research questions are: What are the most important indicators of rural deprivation in Poledokhtar? Which indicators (objective or subjective) can better assess rural deprivation? Moreover, what is the spatial pattern of the dimensions of rural deprivation in this region?
Research Methodology
Research and applied research as the "method", in the context of "cross" occurs. The data are collected in two ways: "documents" and "you know" is. Data collection has also been done in both "documentary" and "field". The statistical population of the research includes the village of Poldokhtar. Using Cochran formula, 400 households are selected randomly from a sample population. To identify the most important deprivation indices, unlimited exploratory uncertainty test (Johansson method) is used in Eviews software version 9. In this test, considering the special values (numerical value), identifying and exploring the most important indicators, they can be ranked. In order to evaluate the objective and subjective indices of deprivation, a one-sample t-test is used to examine the difference between rural areas in terms of deprivation indices of Post-Hoc Anova follow-up tests in Spss software version 22, and to provide a spatial pattern of the system Geographic Information (GIS) be used.
Discussion and Findings
To investigate the most important rural deprivation indices in the study area, an unlimited exploratory coherency test has been used. The findings of this test are shown that among the eighteen indicators considered to measure rural deprivation, eleven indicators are at a low level, and the villages in the region are in a disadvantaged position. Of these eleven indicators, three Index Income and savings (0.219), Ownership (0.120) and Housing (.114) related to economic deprivation, three Index Educational (0.147), Hygiene (0.127) and welfare Services (0.114) related to Social dimension, two Index of cultural infrastructure (0.120) and the rights of ethnicities and minorities (0.164) related to the political-cultural dimension and three Index Village environment (0.135), Street network (0.102) and Rural infrastructure (0.160) related to the Peripheral-physical dimension the deprivation has been. One-sample t-test is used in the context of the importance of the objective and subjective indices of rural deprivation. The findings show that the mean of objective indices is 4.08 and subjective indices are 3.52. The value of sig obtained for the dimensions is also not equal. Both are less than the alpha level of 0.05. This indicates the difference between objective and subjective indicators for assessing deprivation in the study area. Hence, it can be concluded that the respondents consider the importance of objective indicators to be more than mental indices. In rural areas where significant differences exist in the dimensions of deprivation.
Discussion and conclusion
For a number of reasons, rural areas require a careful look and analysis of rural development policies; first, the bulk of the world's population lives in villages. Second, rural areas contain almost all the necessary resources, such as food and energy resources for human life; Third: Urban and rural inequality and rural deprivation. One of the most important strategies for most countries to achieve development is the issue of eliminating rural deprivation. Considering the importance of this issue, this study also identifies important indicators of rural deprivation, analyzing its spatial pattern. The results showed that of the eighteen indicators, eleven indicators are located at the lower level and the villages of the region are deprived of these eleven indicators. Of these, three indicators of income and savings, property and housing related to the economic dimension, three indicators of education, health and welfare services related to the social dimension, two indicators of cultural infrastructure and the rights of ethnic groups related to the political-cultural dimension, and finally Three environmental indicators, road network and infrastructure have been related to environmental degradation. Spatial analysis of the villages of Poldokhtar in terms of deprivation dimensions showed that there is a significant difference between different villages. The degree of deprivation of villages has severity and weakness, and in order to reduce the deprivation, identification of regional indicators of deprivation must be provided for each region. It is therefore proposed to effectively overcome rural deprivation, rural communities need real support, not with plans, programs and political gestures. To reduce rural deprivation, long-term plans for agriculture and livestock should be devised, not by the program. In physical and symbolic terms, it is necessary to provide them with the facilities, not cash or tune their stomachs.
Volume 22, Issue 4 (Fall 2019)
Abstract
Aims: The JAK/STAT signaling pathway is activated by an interlacing-6 family of proteins and plays a crucial role in the hypertrophy process. Also, examining the role of this pathway in cardiac physiological hypertrophy derived by endurance training was the ultimate aim of this research.
Material & Methods: 16 adult male Wistar rats (age, weeks) were used in this research. The rats were selected at random and assigned to one of two groups: Control and endurance training groups (8 rats in each group). Endurance training groups’ rats trained 8 weeks, 5 days/week. 48 hours after the last session, the rats were euthanized. The cardiac tissue was separated and cardiac hypertrophy was measured through considering heart weight to body weight ratio,
left ventricle wall thickness, and cardiomyocytes area. In addition, expression levels of CT1, gp130, JAK2, and STAT3 genes were measured by real-time PCR. Finally, the data were analyzed by the independent t-test. Differences were considered significant at p<0.05.
Findings: The endurance training group had a significant increase in the heart weight to body weight ratio compared with the control group (p≤0.0001). Moreover, analyses performed by staining with Hematoxylin Eosin, shown that the training group had significant increases in the thickness of the left ventricle (p≤0.0001). Yet, measuring expression levels of studied genes revealed that there were no significant differences between the training group and the control group expression levels (CT1: P=0.174, gp130: P=0.054, JAK2: P=0.423, STAT3: P=0.062).
Conclusion: Expression profiling in the training group performed after 8 weeks of training, revealed that the expression levels of genes involved in JAK/STAT pathway genes were not changed significantly. These findings suggest that despite the protective role, the JAK/STAT pathway may not play a crucial role in physiological cardiac hypertrophy.
Volume 23, Issue 5 (Winter 2021)
Abstract
Aims: Anion Exchange Protein 1 (AE1), also known as band 3, is one of the most abundant proteins in the red blood cell membrane and renal tubular a-intercalated cells with two different isoforms (eAE1 and kAE1, respectively). Mutations of the anion exchanger 1 (AE1) gene can cause hereditary spherocytosis (HS) and distal renal tubular acidosis (dRTA).
Materials & Methods: In the present Iranian families, five hereditary spherocytosis Patients with symptoms relative to kidney problems which investigated in from the Ali-Asghar Children’s Hospital. A patient suspected dRTA was employed for genetic analyses with whole-exome sequencing and Sanger sequencing methods. Data were analyzed using the Wilcoxon signed-rank test in SPSS Statistic
Findings: Clinical manifestations and laboratory findings of 5 study patients were observed in growth retardation, Splenomegaly, and significant urine infection. Also, one of 5 patients showed severe failure to thrive, Short stature, repeated urinary infection, and weakness. We have found a Combination of a novel homozygote missense variant (c.2494C>T (p.Arg832Cys) in the anion exchanger 1 and a heterozygote missense variant in SPTA1 gene (c. 466C>T (p. Arg156Trp).
Conclusions: These results confirm the importance of Kidney failure with Hereditary Spherocytosis diseases. The combination of two mutations in the Patient 3 manifested as incomplete distal renal tubular acidosis (dRTA) in the affected patient. We reported for the first time, clinical and genetic characteristics of incomplete distal renal tubular acidosis disease in the affected patient.
Volume 24, Issue 2 (5-2017)
Abstract
Trying to understand the reality of the soul and its result (Self Knowledge Theology) has always attracted philosophers’ attention and has been regarded as one of the concerns of philosophical thinking. In this article, it is specified that the peripatetic philosophers, whether Greek or Islamic, have considered the soul as a chapter of naturalia and try mostly to comment on the soul’s powers and activities; they have not had any epistemological view of it. In contrast, Sheikh Eshragh closes the psychology to the theological discussions and looks at it from the epistemological point of view. His discussion is not about soul’s powers, but he provides a way to save the soul from the prison of the body and emancipate the human being from the darkness of material world. In the illuminationist philosophy, the theory of intuition was proposed for the first time (The substantial form), so it has discussed the nature of the soul from this viewpoint. Suhrawardi’s psychology isn’t a consequence of theoretical discussion, but it results from introspection and self-awareness that is possible only through the asceticism and controlling the dragon of carnal soul. It is soul which shows not only the Light of Lights, but it becomes divine and finally through this path he founds his luminous system. The system of being is realized through the epistemology of soul.
Volume 24, Issue 10 (October 2024)
Abstract
Passive vibration control of rotating nonlinear beams is crucial due to its potential to mitigate harmful vibrations in various engineering applications, including aerospace and industrial sectors. This study examines how different system parameters and inherent nonlinearities influence the vibrations of a nonlinear rotating beam subjected to periodic external forces. A nonlinear energy sink (NES) is attached to the beam's tip to attenuate vibrations. The system is modeled using the Euler-Bernoulli beam theory and von Kármán strain-displacement relations, with equations of motion derived via Hamilton’s principle. Complexification Averaging and Runge-Kutta methods are applied for analytical and numerical solutions, respectively. The findings reveal that increasing the stiffness reduces vibration amplitude, while a rise in the nonlinear coefficient induces hardening behavior. The system exhibits saddle-node and Hopf bifurcations under certain conditions, indicating complex dynamic transitions. These phenomena, driven by the beam's nonlinearity and the NES, effectively diminish the vibration amplitude, highlighting the system's complex dynamic responses and the NES's efficacy in vibration mitigation
Volume 27, Issue 1 (Spring 2023)
Abstract
Due to climate change in recent decades, resilience in times of crisis has become the focus of researchers. The aim of the current research is to analyze the resilience of rural farmers in the wake of drought management and the reduction of damage incurred to the rural community. After investigating numerous studies in the theoretical field of resilience and examine the characteristics expressing the resilience to measure, a combination of the spatial and community-oriented models were used which refer to the dimensions of resilience. Further, the key role of local community as well as social, institutional, economic, physical and ecological dimensions are selected to explain resilience. The research method is quantitative - survey and descriptive, analytical and correlational methods have been used. For this purpose, six villages were selected from Siriz rural district in the north of Kerman province, which are in severe drought condition. Among the 1118 households of the statistical population, using the Cochran formula, a sample size of 286 households was studied. The sampling method in this random research is simple and 286 heads of rural households were interviewed through structured questionnaires. The obtained data were analyzed using one-sample T-test, and correlation coefficient. The results emphasize the weak resilience in all aspects in these 6 villages where the effects of draught intensified and caused a lot of damage to the villagers and specifically to the farmers.