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Showing 12 results for شکوهی


Volume 14, Issue 4 (Winter 2011)
Abstract

This article, to determine aimed the criteria and basis of accessority of accessory contracts in relation to basic obligation, in order to determine the limits and basis of accessority. In this respect, two main theories were considered; theory of subjective accessority and theory of objective accessority. According to the subjective theory, the basis of accessority of accessory contract in respect of basic obligation is the will of the parties. Consequently, this would determine the limits and effects of this accessority. On the other hand, according to the objective theory, the basis of accessority of accessory contracts could be found in this fact that the basic obligation is the subject of the accessory contracts. This material relationship between the accessory contract and the basic obligation results in complete accessority of the accessory contracts from the characteristics of basic obligation. Determination of the accessority criteria would justify different effects and characteristics of the accessory contracts, which will be discussed.

Volume 15, Issue 1 (Spring 2015 2015)
Abstract

Inflation is the main problem which should be overcome both by the government and economic agents. The existence of inflation in an economy causes distortion and disequilibrium in the macroeconomic variables in the forms of decreasing growth rate, rising unemployment rate and uneven income distribution and so on. In addition, the uncertainties caused by the high inflation rates, raise the inflation expectations. This paper tries to found out which type of inflation expectations gives the better explanation of current inflation: backward-looking, forward-looking or some combination of the two? Using Generalized Method of Moments (GMM) and annual data over the period 1976-2008, the results of hybrid Philips model  show that inflation in Iran is significantly determined by backward-looking inflation expectations, forward-looking inflation expectations, the output gap, exchange rate, and liquidity growth. However, backward-looking inflation expectations are more important than forward-looking expectations. The findings imply that managing inflation expectations, liquidity growth, and exchange rate can complement each other to achieve overall price stability.

Volume 15, Issue 12 (2-2016)
Abstract

This paper deals with the collision-free path planning of planar parallel robot by avoiding mechanical interferences and obstacle within the workspace. For this purpose, an Artificial Potential Field approach is developed. As the main contribution of this paper, In order to circumvent the local minima problem of the potential fields, a novel approach is proposed which is a combination of Potential Field approach, Fuzzy Logic and also a novel algorithm consisting of Following Obstacle as well as Virtual Obstacle methods, as a hybrid method. Moreover, the inverse kinematic problem of the 3-RRR planar parallel robot is analyzed and then the aforementioned hybrid method is applied to this mechanism in singular-free case. It is worth mentioning that, in this paper, all the probable collisions, i.e., the collision between the mechanism and the obstacles and also among the links, are taken into accounts. Two general cases have been considered in collision-free path planning simulation; the first case considered a mobile robot in several workspaces and the second one was assigned to the 3-RRR planar parallel robot path planning. Results of the simulations, which are implemented in C programming language for the sake of real-time purposes. reveal that for the both cases, the newly proposed hybrid path planning method is efficient enough for the mobile robot, or the end-effector of the planar parallel robot to reach the goal without colliding with the obstacles.

Volume 16, Issue 2 (6-2016)
Abstract

Digital Elevation Models (DEMs) are one of the most important inputs in most rainfall -Runoff models and also in deriving watersheds geomorphological characteristics. One of the most important issues that should be taken into account when using DEMs in rainfall runoff modeling is the effects of DEM source on the results of the models. At present time, radar based DEMs are attracting a considerable attention in many earth related fields. Currently, there are several sources such as: Shuttle Radar Topography Mission (SRTM) data and the advanced space thermal emission radiometer (ASTER) that due to ease of access and free of charge, have an important role in hydrological modeling and the extraction of geomorphological parameters of catchments. This paper addressed the effects of different DEM sources: ASTER, SRTM, and 1:50000 topographic based DEM on the topographic index and performance of a semi- distributed model, called TOPMODEL. The obtained results indicated that by increasing DEM cell size, disregarding its source, the topographic index inceased. Also, it was illustrated that for all cell sizes other that 30 m there was no difference between the results of ASTER and SRTM DEM. Such a coincidence was observed for TOPO DEM for cell sizes larger than 100 m, as well. Results showed that the effect of data resolution on the average daily discharge, average saturation deficit of basin and the average distance to water table level is not meaningful. In daily discharge simulation, the performance of TOPMODEL when using the TOPO DEM ,based on the NASH- SUTCLIFFE efficiency index, was the highest and for the SRTM DEM was the lowest. In flood simulation, upto 200 m resolution, TOPMODEL efficiency was constant disregarding the DEM source, while its efficiency reduced for cell sizes greater than 200 m in all conditions. It was illustrated that by increasing the cell size, surface runoff contribution to total runoff, in contrast to subsurface flow, increased. Furthermore, For all of the sources, increasing the DEM cell size, incresesd the surface runoff contribution and decreased subsurface flow. The percent of surface flow simulated by the model when implementing the DEM of SRTM is the highest. According to achieved results, the percentage of simulated surface runoff from SRTM DEM was higher than the other two sources. It was observed that the number of cells of low slope in SRTM DEM is greater than the other sources, which was concluded as the main reason for this issue. Reducing the slope of a cell could reduce its potential to carry subsurface flow, which in turn could increase the cell potential to be saturated. It was concluded that DEM different sources effects on average saturation deficit and water table is negligible, and these ouputs of TOPMODEL is mainly affected by DEMs cell size. Finally, this important conclusion was drawn from the present research that the information content of ASTER DEM is nearly similar to TOPO DEM and higher than SRTM DEM; therefore, between satellite based DEMs, it is more convenient to use ASTER DEM for rainfall runoff modeling.
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Volume 17, Issue 2 (Summer 2013)
Abstract

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Volume 18, Issue 1 (may 2018)
Abstract

Rainfall Runoff modeling especially in ungauged watersheds is almost dependent on hydro-geomorphologic data. In this regard, the effects of data and DEM resolution on deriving watershed’s geomorphologic data such as subbasins area, channels and subbasins’ slope should be well realized in modeling. In this research, HEC-HMS as the rainfall runoff model and two subbasins with different areas, geomorphologic properties and climate were selected for studying. By reducing the cell size of the DEM derived from a topo map, simulated peaks increased. For DEM cell sizes less than 100 m, the differences in simulated peak were limited to 2 to 5%. Using SRTM DEMs against the topo DEM at the scale of 1:25000, representing the effects of data resolution in rainfall runoff modeling, led to obtaining higher flood peaks at the two watersheds. Such an outcome was obtained for time to peak, hydrograph base time, and the slope of hydrograph rising limb. Change of SRTM DEM resolution affected the model output more than the case of using topo DEM. Decreasing DEMs resolution by decreasing information content of the topo DEM reduced differences in the model output when using two different sources of DEM. Furthermore, it is concluded that the extent of scale effect in modeling could not be inferred by watershed size. It was illustrated that HEC-HMS application in a watershed of more diversity was more sensitive to data resolution. Using cell size of 100 m and less could guaranty the result of the HEC-HMS application regardless of DEM origin and size of watersheds. Rainfall Runoff modeling especially in ungauged watersheds is almost dependent on hydro-geomorphologic data. In this regard, the effects of data and DEM resolution on deriving watershed’s geomorphologic data such as subbasins area, channels and subbasins’ slope should be well realized in modeling. In this research, HEC-HMS as the rainfall runoff model and two subbasins with different areas, geomorphologic properties and climate were selected for studying. By reducing the cell size of the DEM derived from a topo map, simulated peaks increased. For DEM cell sizes less than 100 m, the differences in simulated peak were limited to 2 to 5%. Using SRTM DEMs against the topo DEM at the scale of 1:25000, representing the effects of data resolution in rainfall runoff modeling, led to obtaining higher flood peaks at the two watersheds. Such an outcome was obtained for time to peak, hydrograph base time, and the slope of hydrograph rising limb. Change of SRTM DEM resolution affected the model output more than the case of using topo DEM. Decreasing DEMs resolution by decreasing information content of the topo DEM reduced differences in the model output when using two different sources of DEM. Furthermore, it is concluded that the extent of scale effect in modeling could not be inferred by watershed size. It was illustrated that HEC-HMS application in a watershed of more diversity was more sensitive to data resolution. Using cell size of 100 m and less could guaranty the result of the HEC-HMS application regardless of DEM origin and size of watersheds.

Volume 19, Issue 130 (December 2022)
Abstract

This study aimed to investigate the effect of chemical modification with adipic acid/acetic anhydride mixture (1:30) on the physicochemical and functional properties of amaranth starch and also to determine the optimal conditions for amaranth starch chemical modification with the mentioned mixture. Amaranth starch was isolated and then modified under nine different treatments designed by the Taguchi method using three main chemical modification factors, including the mixture of adipic acid /acetic anhydride concentration (4%, 6%, and 8%), reaction time (60, 90 and 120 min) and suspension pH (8, 8.5 and 9). Swelling power, solubility, color, paste clarity, thermal properties, freeze-thaw stability, and apparent viscosity of starch samples were investigated. Modification optimal conditions were determined using Taguchi analysis and the related percentage deviation (RPD) method. The result obtained from this study showed that the chemical modification significantly changed the physicochemical and functional properties of amaranth starch. Adipic acid/ acetic anhydride mixture improved the swelling power, solubility, viscosity, and paste clarity of modified starch than native. Modified starch powders showed more lightness, less yellowness, and redness in color. Chemical modification reduced gelatinization temperatures, gelatinization enthalpy, and freeze-thaw stability. However, since other food components such as sugars, salt, hydrocolloids, etc., influence the freeze-thaw stability of starch, the possibility of modified amaranth starch utilization as a stabilizer, thickener, or fat replacer in food products with the mentioned mixture needs additional research is required to be conducted. The optimum modification conditions were a concentration of 6%, a reaction time of 120 minutes, and a pH of 9.

Volume 20, Issue 4 (1-2017)
Abstract

Interaction of companies with customers in the form of customer relationship management has changed significantly. Identifying characteristics of different customers and allocating resources to them according to their value to the firm has become one of the main concerns in customer relationship management. The purpose of this paper is to provide an appropriate model for customer segmentation based on some of the most important financial and demographics characteristics influencing factors of customer lifetime value (CLV). The process proposed in this study was performed in Saman insurance company. After determining RFM model indices, which include date, frequency and monetary of purchase, AHP method used for weighting them among 180000 customers. The optimal number of clusters based on the silhouette and impact of RFM indicators was done by using Two-step algorithm and then customers classified through K-Means clustering algorithm. Results provided a platform to analyze the characteristics of customers in three main sections. Also, by prioritizing clusters based on the RFM indices, valuable customers were identified. Finally, some suggestions were presented to the company to improve its customer relationship management system.

Volume 20, Issue 135 (May 2023)
Abstract

In this research, quinoa starch samples were evaluated in 9 treatments with different proportions of adipic acid and acetic anhydride mixture (ratio 1 to 30), along with a control sample in terms of physicochemical and functional characteristics and determining the optimal conditions for chemical modification. The mentioned treatments were designed by 3 independent variables affecting chemical modification, including chemical modifier concentration (2%, 4% and 6%), suspension pH (8, 8.5 and 9) and reaction time (60, 90, 120 minutes) by Taguchi method. became The swelling power and water absorption capacity of sample T2 (modifier concentration 2%, suspension pH 9 and reaction time 120 minutes) significantly increased compared to the control sample, which is a sign of the formation of crosslinks along with the formation of stable three-dimensional gel networks. Spectroscopy results showed that except for T2 sample, the rest of the samples had a slight tendency to retrogradation, which was a sign of the high stability of the said sample during the retention period to syneresis (p<0.05). Acetylation significantly improved the solubility characteristics compared to the control sample due to the better dispersion of starch in the aqueous medium. With the increase in the modifier concentration, the stability of the samples against the freeze-thaw cycle decreased significantly (p<0.05). The investigated parameters in measuring the thermal characteristics of modified quinoa starch were evaluated with a significant difference more than the control sample. The apparent viscosity of the T2 sample at the shear speed of 20, 50 and 100 rpm increased significantly compared to the control sample, but the other samples showed a lower viscosity. Also, using Taguchi analysis, the optimal treatment of modified quinoa starch with 2% modifier concentration, suspension pH 9 and reaction time 120 minutes was determined.

Volume 20, Issue 141 (November 2023)
Abstract

The usage of plant extraction such as tannins, flavonoids & et. as an alternative to fungicidal effects. The aim of this study was to evaluate of  the antifungal effect of Iranian oak Jaft extract after extraction by different methods on Penicillium italicum and (Penicillium digitatum as an indicator of citrus fruit mold spoilage. molds were expossered by different concentrations of oak Jaft extract. The investigated factors including minimum inhibitory concentration (MIC) (mg/ml), minimum lethal concentration (MFC) (mg/ml) and non-growth diameter (mm) were determined by the methods of tube dilution, surface culture and diffusion in agar well (WD). The results showed that different concentrations of aqueous extract had significantly effect (p<0.05) on the non-growth  diameter of molds. The antifungal effect was significantly (p<0.05)increased in concentrations of 40 and 80 mg/ml aqueous extract. In this research, Fludioxionil 25%  poison as a control group showed a significant difference(p<0.05) in molds growth. In general, the extract of Iranian oak Jaft can be used to control the fungal spoilage of citrus fruits.
 

Volume 23, Issue 1 (Spring 2019)
Abstract

Abstract
 
Introduction: resident’s empowerment in a tourism region is essential to ensure the success and development of sustainable tourism. Empowerment can affect people's attitudes toward the positive and negative impacts of tourism. In addition, studies suggest that residents are more willing to support tourism development if its impacts are perceived to carry greater benefits than costs. Hence, empowerment is expected to be able to support the development of tourism. this study aims to investigate if empowerment could affect their attitudes toward tourism impacts and support of tourism development.
Methodology: This study is an applied research and with the survey method was conducted. The study population consisted of residents of Kamardough tourism region. The sample size was determined using the Morgan table (n=220). Using a random sampling method, 220 students were selected for this study. The face validity of the questionnaire was confirmed by a panel of experts. Cronbach alpha reliability coefficients were calculated for the pilot study and used to refine the questions for the final questionnaire. All scales indicated good-to-excellent reliabilit generally 0.71–0.91.
Results and discussion: Regression showed that Personal economic benefit and three empowerment dimensions (psychological, social and political) had direct and significant relationships with resident perceptions of tourism’s positive impacts. These variables predicted 51% of the variance in attitude toward positive impacts. Personal economic benefit and political empowerment have significant effect on attitude toward negative impacts of tourism. There is a negative relationship between political empowerment and perceived negative impacts from tourism. These variables predicted only 0/28 of the attitudes toward negative impacts. the Regression showed that psychological empowerment, social empowerment and political empowerment and attitudes toward positive impacts of tourism affect residents’ support for tourism. These variables predicted 47% of the variance in support.
Conclusion: These findings also have practical implications for those within the tourism industry looking for strategies to increase their residents’ support for and attitudes toward tourism development.
 


Volume 28, Issue 3 (autumn 2024)
Abstract

In recent decades, the term "right to the city" has been noticed first in philosophy and then in urban planning. Perhaps the right to the city can be defined as the right of citizens to benefit a rich cultural urban space. Based on this, urban development plans can play a significant role in realizing or not realizing this right. The question is how to find out to what extent an urban development plan is based on the right to the city? In order to answer this question, a scale should be proposed to measure the right to the city in urban development plans. Due to the relative nature of the achievement of the right to the city in urban development programs, the present research, while proposing a scale, by selecting two study samples (Tehran Comprehensive Plan and Paris Sustainable Development Plan), uses the comparative method in evaluating the right to the city.
 The research approach is a documentary and comparative approach. In the first step, while examining the theoretical foundations and existing literature (based on the opinions of Lefebvre, Soja and Harvey), a framework for measuring the right to the city in urban development programs is proposed, and then a comparative study has been done based on the data obtained from the study of the documents of the Tehran Comprehensive Plan and the Paris Sustainable Development Plan (Le Projet d'Aménagement et de Développement Durable- PADD) as well as the results of in-depth interviews with the planners and urban managers of Tehran and Paris.
The research approach is a documentary and comparative approach. In the first step, a framework for measuring the right to the city in urban development programs is proposed via examining the existing literature (based on the opinions of Lefebvre, Soja and Harvey). Then a comparative study has been done based on the data obtained from the study of the documents of the Tehran Comprehensive Plan and the Paris Sustainable Development Plan (Le Projet d'Aménagement et de Développement Durable- PADD) as well as the results of in-depth interviews with the planners and urban managers of Tehran and Paris.
The results indicate that urban development plans can be articulated based on to the right to the city along a continuum ranging from "the eradication of religious and racial discrimination" to "the right to urban existence". Furthermore, the comparative analysis of the urban development plans of Tehran and Paris, utilizing this proposed continuum range, reveals that the notion of the right to the city is significantly diminished within the Tehran comprehensive plan. Although the Tehran comprehensive plan document acknowledges certain facets of citizens' rights pertaining to urban existence, it predominantly adopts a physicalistic perspective, thereby neglecting the citizens' entitlement to experience an environment imbued with identity and cultural richness. Conversely, the sustainable development agenda of Paris contemplates a more elevated conception of the right to the city, such that it incorporates the right to the city at the level of "equitable access to economic and social opportunities" as a fundamental component of its strategic framework.


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