فهرست مطالب j.ahmadi

The spatial arrangement of housing, pertaining to the interconnection of spatial components, exhibits an intricate relationship with all architectural challenges and concerns. Consequently, the objective of this research endeavor is to scrutinize and explore the arrangement of modern structures in Mashhad, aiming to identify discernible patterns.

The current investigation adopted a practical approach and was carried out within the confines of Mashhad city in 2021, employing a mixed qualitative-quantitative methodology. A comparative-descriptive analysis was performed on the residential layouts of Mashhad city. The sampling technique utilized was random, leading to the selection of a cluster comprising 61 samples from 17 districts of Mashhad.

A total of 44 distinct graphs were observed, with the predominant layouts in Mashhad being those consisting of six or seven nodes. These nodes typically encompass areas such as the entrance space, reception area, parents' bedroom, child's bedroom, kitchen, and bathroom. Analysis of the connection parameter revealed that the minimum maximum value among the depicted graphs was 2, whereas the maximum peak value stood at 4. In terms of the selection parameter, the highest rating reached 2 due to the limited number of internal spaces, while the lowest rating was 1.

The primary structure common to all graphs entails an entrance space leading to a reception area. Spatial organization has been prominently upheld in the majority of designs, with particular emphasis on the kitchen and service areas as pivotal zones within the layouts.

Record values have many applications in reliability theory, such as the shock and minimal repairs models. In this regard, many works have been done based on records in the classical model. In this paper, the records are studied in the geometric random model. The concept of the mean residual of records is defined in the random record model and some of its properties are investigated in the geometric random record model. Then, it is shown that the parent distribution can be characterized by using the sequence of the mean residual of records in a geometric random model. Finally, the application of the characterization results to job search models in labor economics is mentioned.

All important decisions that affect the thermal performance of the building are made in the early stages of design. Accordingly, in this research, the initial stage of architectural design which is related to space plan was targeted. The aim of this research is the perfect approach to evaluate, and optimize the energy a set of alternative spatial layout solutions through the functional computational design model. The method of this research includes the production of coherent design solutions and the evaluation and optimization of the energy performance of the selected solutions. In the first part, space allocation at a level produces the plan through an evolutionary technique. In the next step, certain plans were evaluated for energy performance, performance rank, and optimization. The energy simulation tool is Honeybee and Ladybug plugins,. The optimization tool is Pareto Evolutionary Algorithm in the Octopus plugin. The reproduction rate, the mutation rate and the possibility of mutation were 0.9, 0.8 and 0.2, respectively. The results showed that each algorithm is a suitable tool for design solutions, thermal performance of floor plans, helping architects’ perspective in the decision-making process, and speeding up the design process. Finally, based on the optimization, the final result of the research algorithm is 70 elite answers in the Pareto front. Only during the Pareto front optimal responses, energy consumption can be reduced by more than 30%; in daylight time and more than 39% improvement was achieved.

In this paper, using the linear and non-linear vehicle-driver model, the effect of the driver's time delay on the vehicle lateral stability has been investigated. Driver's time delay is an unavoidable issue in vehicle handling dynamics. Apart from intrinsic time-delay in human sensory-motor response, the driver's health condition can potentially affect the reaction-time. Taking into account the driver time delay in the modeling, transforms the vehicle handling dynamics to a system of delay differential equations (DDE), which has infinite solution in mathematical sense. In this paper, to solve the follow-on DDE, the time delay is approximated via a Taylor series. Stability charts, demonstrating the acceptable regions for driver's proportional and derivative gains are provided for a specified driver time delay. The results show that as the time delay increases or the vehicle speed increases, the stability region becomes smaller. The critical value of driver time delay for a specified set of driver’s proportional and derivative gains is also calculated. This analysis shows that if the driver drives at higher speeds, he must react faster so that the vehicle does not become unstable. Numerical simulation of a vehicle driver model subjected to a rigorous lane change maneuver is carried out to verify the results obtained from the stability charts. In the simulation a nonlinear seven degrees of freedom of vehicle and a nonlinear tire model is used. The simulation results fully confirm the stability analysis results.

Aegilops range grasses (Poaceae family) as one of the most important ancestors of wheat is a rich source of stresses tolerance genes. For this, the fingerprinting of genetic relationships in accessions belonging to eight species of Aegilops was studied using targeted genes-related CoRAP molecular markers. In designing the fixed primers, six genes CAT, MnSoD, SoS1, miR398, miR160b and miR169gR responsible for abiotic stresses tolerance were used. The lowest and highest polymorphic information contents were related to CoRAP2 and CoRAP10 primers with 0.92 and 0.96, respectively. The marker index varied from 6.89 in CoRAP7 primer to 13.49 in CoRAP9 primer. Low gene flow (Nm) and high differentiation (Gst) was observed between species. Also, the Fst index equal to 0.45 showed that the studied populations were completely separated. Due to the high values of the effective allele number and Nei genetic diversity, two species Ae. cylandrica and Ae. caudata showed high intra-specific diversity. The greatest similarity was observed between two species Ae. truncialis and Ae. umbelulata as well as Ae. neglecta and Ae. cylanrica. Cluster analysis appropriately divided species into distinct groups, and principal coordinate analysis confirmed the results of cluster analysis. Using structure analysis of the population, the mode of gene flow and genetic intermixture among species were in accordance with the grouping results of cluster analysis and PCoA biplot.

Urania nanostructures were synthesized by a facile, which is a simple and clean and straightforward deposition method, for two different deposition time durations. The morphology and structures of the products were characterized by the X-ray diffraction analysis (XRD) and Scanning Electronic Microscopy (SEM). The SEM images indicated that the morphology of the synthesized samples for 10 minutes was composed of a coin-like structure with a nano-scale dimension in a narrow- size distribution. The results indicated that the deposition time affects the morphology while it does not affect the structure. The XRD results identified the sample structures as UO2 </sub>crystal. The chemical composition of different points of the sample surface was determined by the energy dispersive spectroscopy (EDS) technique and the results clarified that the samples have a homogeneous composition of uranium oxide. The synergistic properties of the substrate surface, and uranium ions are responsible for the formation of an outstanding and a novel structure.

Dual purpose cask system is one of the most important developing systems of dry interim storage of nuclear spent fuels. Thermal evaluation of a dual purpose cask designed for transport and interim storage of spent fuels of Bushehr Nuclear Power Plant is carried out as appears in this paper. SolidWorks and ANSYS Workbench 15 are utilized for the modeling and thermal simulation of the cask under normal condition of transport, as well as, normal condition of interim storage, respectively. According to the results, the maximum temperature of the fuel cladding will not exceed the allowed limits and the fuel integrity will be maintainel. Furthermore, the temperatures of the other components are predicted in the range of allowed limits, demonstrating the safety of the cask under the normal conditions based on the IAEA safety standards.

Olive is considered one of the most significant crops, with more than 1200 distinctive cultivars and an abundant number of wild forms. In this study, the genetic diversity in a set of Iranian and foreign olive cultivar was evaluated using ISSR primers. Using 16 ISSR primers, a total of 190 bands amplified, which out of 172 were polymorphic. The average of resolving power (Rp) and polymorphic information content (PIC ) was 10.22 and 0.45, respectively, hence this indicating the high efficiency of these primers to further genetic diversity assay. The results of analysis of molecular variance (AMOVA) showed 7% of the total genetic diversity refer to among groups, while 93% of the total variation was found within groups. The average percentage polymorphic loci (PPL), number of observed (Na) and effective (Ne) alleles, Shannon’s information index (I), and gene diversity (H) are 82.11%, 1.73, 1.43, 0.39 and 0.26, respectively, and Iranian cultivars showed higher amounts of all parameters than foreign cultivars. Genetic relationships inferred from a neighbor-joining dendrogram clustered cultivars into main three groups. This grouping pattern was matched with the groups obtained by principal coordinate analysis (PCoA). Taken together, the results obtained from this study indicate the ISSR primers used in this work will be useful for genetic diversity and phylogenetic studies in the olive cultivars. Hence, the use of these primers in other genetic studies like QTL and association mapping are recommended.

Wild relatives of wheat have served as an ideal gene pool for improving drought tolerance in wheat. The objective of this study was to investigate the expression patterns of several antioxidant genes comprising MnSOD, APX and GPX in the different cultivated and wild wheat species under control (90% field capacity) and drought stress (25% field capacity) conditions. For this purpose, a factorial experiment based on randomized complete block design with four replications (two biological and two technical replications) was conducted to compare five species of Aegilops and two species of Triticum along with two bread wheat check cultivars SIRVAN (as resistant to drought) and DARYA (as sensitive to drought) in greenhouse. The analysis of variance for the relative gene expression values showed significant effects for the drought stress, species and their interaction. Drought stress increased expression of MnSOD, APX and GPX by 9.55, 12.64 and 10.18-fold more than the control condition, respectively. Moreover, the results obtained by species comparison indicated a differential expression pattern of these genes among species. As a remarkable result Ae. tauschii, Ae. speltoides and Ae. cylindrica species showed higher expression than other species as well as the tolerant control variety when subjected to a high level of drought stress. Therefore, further studies on these species to determine the mechanisms associated with tolerance to drought stress are recommended.

In this paper, a new two-sampling scheme is proposed to construct appropriate confidence intervals for the lower population quantiles. The confidence intervals are determined in the parametric and nonparametric set up and the optimality problem is discussed in each case. Finally, the proposed procedure is illustrated via a real data set.

Nowadays one of the solutions to protect aquifers in developed countries is to prevent contamination of aquifers. In this study Salafchegan-Neyzar Aquifer vulnerability against agricultural pollution was evaluated, by Drastic and GIS models. In this method, seven hydrogeological factors that were effective in groundwater pollution were combined. The seven factors are: watertable depth, the net recharge aquifer, aquifer media, soil media, topography and the unsaturated hydraulic conductivity. Vulnerability zoning maps were drawn from the results obtained. Zones vulnerable to nitrate pollution were determined. Using GIS techniques and by single-parameter sensitivity analysis, the influence of parameters used were investigated. Results showed that depth to water table aquifer of Salafchegan was the most important factor influencing vulnerability in Salafchegan-Neyzar aquifer. The results of different qualitative zones was shown in four categories of very low, low, medium, high which were 550, 853, 150 and 498 square kilometers before the correction of model were converted to 351, 486, 401 and 425 after the model correction. In general, sensitivity analysis showed that effective and theoretical weight of using parameters, aren’t fully coincide and in some cases have considerable differences.

Hypercholesterolemia is major risk factors for heart disease. Plant sterols have been used for reduction of cholesterol since 1950 decade; so enriching food materials with such components is important. Major problems related to enrichment of products with plant sterols are high melting temperature and chalky taste. In addition, crystal form of these components in comparison with lipid-in solved forms can not significantly reduce the blood cholesterol. In this study enrichment of yogurt and optimization of the process condition were investigated. A four components (plant sterols, emulsifier, vegetable oils and water) mixture design was used to define the percentage of each mixture component to simulate wide range of mixture with different oil quantities. Emulsifier and soy oil were used for dissolving and dispersing of plant sterols in water phase. Yogurt texture, syneresis susceptibility, acidity and viscosity were measures during storage. Gel strength of enriched samples was higher than control. The mean values of syneresis and viscosity of enriched yogurts with phytosterol, were significantly (P < 0.05) lower than the control yogurt. Addition of plant sterol into yogurt did not change titrable acidity. Taste and flavor tested by panelists, where enriched yogurt was preferred to control.

Generation mean analysis (GMA) was used to study the type of gene action and inheritance of grain yield and its components. Generation mean analysis with joint scaling test was performed. This research was conducted at research farm of college of Agriculture at the University of Tehran. The parents and their progenies ( F1, F2, BC1 & BC2) in three mating groups ( Sardari × 7007, Sardari × 7107& 7107 × 5593) were produced and planted using a randomized complete block design with four replications for each mating group. Of four replications in each experiment, two replications for drought and two replications for non-drought condition were used. The eight traits which were evaluated included grain yield, plant height, plant weight, tiller number, spike length, grains per spikes and 100 grain weight. Most of the genetic parameters including mean (m), additive (d), dominant (h), additive × additive [i], additive × dominant [j], and dominant × dominant[l] effects were significant. However, all gene effects were not significant in all traits.The dominant gene effect was the most contributor factor to inheritance of the majority of traits. For the majority of the traits, additive gene effect was significant, but its magnitude was less than dominant gene effect. Also the dominant × dominant[l] epistasis was more important than additive× additive [i] epistasis. The degree of dominance in most of traits indicated the predominance of dominant gene effects.