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Showing 10 results for farajollahi


Volume 1, Issue 1 (3-2013)
Abstract

This research was carried out to investigate allelopathic effect of Peganum harmala on seed germination of Bromus tectorum. Aboveground and underground tissues of Peganum harmala in addition to its seeds were collected from Bijar rangelands. Collected materials of root, leaves, stem, seeds and a complex of mentioned parts were dried and powder. The research was performed at the greenhouse condition. The treatments included 1, 3, 6, 9 and 12 weight percentage of above mentioned powders. Also a control treatment was used, too. A completely randomized design (CRD) was applied for 4 weeks. Germination seeds were counted and recorded daily. Germination properties included: germination percentage, mean germination time, germination speed, inhibitory percentage. At the end of study period, radicle and stem length were measured. Data were analyzed by ANOVA. The results revealed that allelopathic effect of P. harmala resulted in negative effects on germination properties of Bromus tectorum. The high concentration of P. harmala has strong Allelochemicals inhibitory effects on germination and initial growth characteristics of B. tectorum. It was found that the materials obtained from different tissues of P. harmala had different levels of inhibition on germination properties of B. tectorum, so that seeds were the most inhibitor tissues. The lowest germination percentage and seedling growth resulted from 12gr powder of seeds.

Volume 4, Issue 2 (6-2016)
Abstract

The runoff generation and soil erosion in the Kechik Watershed, Golestan Province, was assessed, using a designed and constructed portable rainfall simulator. Treatments were applied on different land-uses, slopes and aspects as the most influential factors. Results showed that land-use significantly affected runoff generation (13.35 l, 6.9 l, and 4.12 l, respectively for agriculture, forest and rangeland uses), however slope (7.7 l for Class I; 9.23 l for Class II) and aspect (8.52 l for the northern aspects; 8.32 l for the southern aspects) did not have significant influence. All factors, significantly altered sediment concentration (Agriculture 9.6 g l-1, forest 8.24 g l-1, and rangeland 5.26 g l-1; slope class I 6.6 g l-1 and slope class II 8.7 g l-1; northern aspect 8.7 g l-1, and southern aspect 6.9 g l-1). Agricultural fields generated the highest runoff and sediment under simulated rainfalls. Rangeland and forest did not have significant runoff generation and sediment concentration. Results showed that land-use management, especially in terms of agriculture, could not only hamper current erosion, but reduced further advancement of this encroaching phenomenon.

Volume 5, Issue 1 (3-2017)
Abstract

The socio-economic factors affecting land use changes in the Maraveh Tappeh region was determined from the viewpoint of beneficiaries and experts. The items of questionnaires designed as rating scale based on the five options Likert. Reliability of questionnaires was determined by Cronbach's alpha. Two sets of questionnaires were designed for beneficiaries and experts. Reliability of beneficiaries and experts questionnaires obtained 0.75 and 0.80, respectively. A total of 310 beneficiaries and 42 experts responded to the questionnaires. Mann-Whitney non-parametric test was used to compare the mean between the experts and beneficiaries. The reality amount of significant difference was obtained from the effect size. Rating average was used for each item and its priority. In ten items, significant difference at the 0.01 level between the viewpoints of beneficiaries and experts was observed. The high cost of living, low income of rural families and unemployment in rural areas were the top three priorities from the viewpoint of beneficiaries. The low income of rural household, the high cost of living and increasing the price of farmland were the most effective factors from the viewpoint of experts. Economic factors were the key priorities of land use change in viewpoint of both beneficiaries and experts, indicating that experts had the necessary experience and understanding of beneficiaries’ condition and were positive and important notes for policy making and management issues.

Volume 5, Issue 4 (winter 2024)
Abstract

Aims: Despite the existence of potential human and executive forces in Iran, industrialization and the use of materials in buildings in order to prevent the waste of materials, has gone through a very slow process, and considering the importance of the construction sector in Iran's economic activities, it is necessary to take effective measures to be done in this context. For this purpose, this research has been carried out with the aim of identifying and ranking the effective indicators on the waste of materials according to the existing theoretical foundations.
Methods: In terms of the purpose of this research, it is a developmental type of research, and in terms of the method of doing the work, it is descriptive, survey and document type. In order to identify the effective factors, a sample was selected from among the community of experts in this industry with a simple random sampling method, and the desired data was collected by distributing a questionnaire and analyzed with SPSS statistical software.
Findings: The research showed that proper design  has the greatest effect on the increase in construction waste. After that, the construction industry  in the second place, education  in the third place, financial resources and economic justification  in the fourth place and finally the reserve and warehouses  have the least impact on the increase of waste.
Key Words: Modern Materials, High-Rise Buildings in urban centers, Zero Waste.
 
Rahim farajollahi, Gholamhosein Sharifi Voldani,
Volume 6, Issue 24 (12-2018)
Abstract

As the most prominent hero of the early history of Islam, Imam Ali (AS), the first Imam of the Shiites has always been considered by religious narratives and storytellers. Nowadays, there are diverse narrative fictions on his character. Some of these stories, apart from their fictive and non- historical behavior have their roots in historical facts (Fath , Kheibar, Khandagh) , but some of them belong to the esprit of writer. In this study, the author will examine the narratives and history of one of these stories entitled “Bae’r Zat-al-Elm”   dated from 2th to 13th centuries. In the first section, the author will present the evidence and narratives of this story in historical order and then by comparing the elements of the story with historical texts to its historical core, we will finally examine the historical evolution of the “Bae’r Zat-al-Elm “ as a geographical name.

Volume 9, Issue 4 (Fall 2021)
Abstract

Aim The present study aimed to analyze the strategies based on natural resource potentials to improve the livelihood of rural households in Najafabad region of Kurdistan province using SWOT analysis.
Methods The statistical population of this study included experts and rural residents. The sample size was 337 rural residents and 51 experts based on Cochran formula and matching with Krejcie and Morgan table. The items of questionnaires designed as a rating scale based on the five options Likert. Reliability of questionnaires was determined by Cronbach's alpha that obtained 0.85 for rural residents and 0.82 for experts. SWOT model was used to determine strategies for improving the livelihood of rural households.
Findings According to the results, “natural potentials such as suitable rangelands for animal husbandry” and “the presence of local, committed and experienced manpower in the village” were determined as the most important strengths from the viewpoint of experts and rural residents, respectively. “Traditional use and exploitation of rangeland and agricultural lands” and “high unemployment rate and low income” were determined as the most important weaknesses from the viewpoint of experts and rural residents, with a relative weight of 86.27 and 86.62, respectively. “The existence of a favorable vision and serious effort for rural development in the country” and “providing credit facilities and low-interest loans” were the most important opportunities.
Conclusion A competitive strategy has been obtained for improving the livelihood of the studied region relying on teaching and planning new methods of exploiting water resources and planting drought-resistant species.

Volume 13, Issue 3 (Fall 2023)
Abstract

Aims: The project's primary aim is to better understand the skills and knowledge necessary for success in the architecture field, as well as to evaluate the intelligence and aptitude of those intending to pursue a career in architecture, which will ultimately benefit job counseling.

methods: An investigation into Gardner's multiple intelligences theory was conducted by employing the Delphi method and a qualitative research questionnaire, with ten experts being asked questions. By using a methodical quantitative questionnaire, this research approach provides insight into the ratio of intelligence and its sections that are either natural or acquired and determines the influence of nature and nurture on architecture tasks by mathematics calculations.

Findings: The achievement of architectural skills is influenced by the nature and nurture components in approximately equal amounts, which in the contract principles are at least 5/1, consisting of 25/49 for nurture and 75/50 for nature. Likewise, a maximum of 7/16 percent goes to management plans and interaction with clients, 75/41 to nurture, and 25/58 to nature.

Conclusion: Concerning the effects of nature and nurture, the pursuit of architecture at the academic level should be done with one's genes and characteristics inherent in a person. On the other hand, the importance of nurturing in training highly qualified individuals is greater than its counterpart and therefore should be adequately maintained.
 

Volume 15, Issue 6 (8-2015)
Abstract

The fThe flow field around the axisymmtric stream lined bodis which forms the main body of the airplaines and submarines has been the subject of several researches. Turning maneuvers of submarines result in cross flow separation that generates large hydrodynamic forces. The separation of a simple axisymmetric body is very complex in nature. Understanding these vortical flows is paramount to improving vehicle performance and design. A suitable way to reduce the effects of this separated flow is to use vortex generators. The main goal of the present study is to investigate the flow field around a Suboff standard underwater model employing the vortex generator by using the oil flow visualization method and CFD method (OpenFOAM code) at 0° ≤ α ≤ 30° angles of attack. The novelty of the this study is the application of oil flow visualizing method and CFD simulation which can help us to precisely study the structure of three-dimensional vortical flow field. The results show that Vortex Generators placed along the submarine do indeed significantly reduce cross flow separation, size of vortices and drag forces.

Volume 20, Issue 136 (June 2023)
Abstract

Tooth decay is one of the most common problems in the world, which is caused by the growth of biofilm and acid production by them. Many solutions have been used to solve this problem. However, due to the increase in antibiotic resistance of microorganisms and the increasing need for antimicrobial substances, efforts are being made to use natural antimicrobial substances. Lactoferrin is a protein in milk and saliva with antimicrobial and anti-biofilm properties. In this research, lactoferrin was encapsulated by nanoliposomes to increase its antimicrobial properties. In order to measure the effect of lactoferrin on the number of bacteria in the polymicrobial biofilm and acid production, each of the free substances or nanoliposomes in 4 concentrations (0, 1.5, 3, 6 mg/ml) in the Active Attachment biofilm model with saliva and culture medium was incubated.
The results showed that lactoferrin nanocoating increased the ability to inhibit biofilm and acid production by this bacterium due to the slow release of lactoferrin from liposomes. When increasing the concentration of free and nanoliposomal lactoferrin to a concentration of 3 mg/ml, a significant decrease in the number of bacteria in the biofilm was observed compared to the control sample (P<0.01). However, increasing the concentration of free lactoferrin again increased the number of bacteria in the biofilm. Meanwhile, nanoliposomal lactoferrin at a concentration of 6 mg/ml still caused a decrease in bacteria in the biofilm, which was insignificant compared to the concentration of 3 mg/ml (P>0.01). From the obtained results, it can be concluded that nanoliposomal lactoferrin can be used to design products related to oral and dental health.
 

Volume 23, Issue 4 (10-2023)
Abstract

Airports are one of the most vital infrastructures of any country, which play an important role in transporting cargo and passengers to different parts of the world. The preservation and optimal use of airport resources and assets is one of the main goals of airport managers. On the other hand, airlines have a special concern on saving time, fuel consumption, maintaining passenger satisfaction, and so on. One of the most important resources in the world's major airports are the gates of the passenger terminals of airports, which have an undeniable aspect in the better performance of the airport. The assigning of aircraft to these gates has long been a concern for researchers in operations research as well as air transport activists. This research deals with the issue of assigning aircraft to the passenger terminal gate. The problem of optimal gate assignment is a complex issue and requires consideration of many parameters and variables in order to achieve the desired result. In this research, it’s tried to solve the gate allocation problem by presenting a suitable model. Providing an appropriate linear model is one of the main challenges of the problem. A special attention has been paid to the issue of safety. Therefore, by applying safety restrictions, a suitable model is provided. The main purpose of this study is to minimize the scatter of idle (lost) gates while not preventing mismatch between flight size and gate and also justifying safety needs. These cases are assigned and examined in the framework of the optimization model in this research. To solve such problems, which are usually not possible by manual calculations or are very time consuming, the metaheuristic algorithms are used. Since because NP-Hard nature of problem, it is very time consuming and difficult in the usual way. Therefore, this study tries to provide an efficient and fast way to solve the gate assignment problem. In the proposed method, first all the sentences of the objective function were considered as, then all were divided into two categories of hard and soft constraints. On the other hand, in the model of the basic method, the power of two terms in the objective function is used. The proposed model was modified. In the end, it was tried to modify the terms of the objective function and constraints in such a way that in addition to meeting the expectations and constraints of the problem, it allows the use of two flights from the same gate (MARS effect) to increase resource efficiency. The method is based on a genetic algorithm that includes the initial population, selection, combination or mutation, generation of a new offspring, and re-selection. In this study, 5 scenarios with various flights and gates have been used. The improvement of total idle times in the first scenario was 72.75%, in the second scenario 76.92%, in the third scenario 82.38%, in the fourth scenario 82.38% and in the fifth scenario 79.67%. All of results. Show the efficiency of proposed model.

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