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Sound is one of the important factors in creating a good feeling in a mosque and it can play a role as a sensory medium to communicate spiritually with God. Therefore, the acoustic standards have defined the optimal level for the mosque in the field of various variables. In order to compare the acoustic conditions of the use of the mosque with the standard limits, the present research has carried out field measurements and software analysis of the standing position in order to simulate the prayer position. Form and volume are the two considered architectural parameters and Background Noise (BN), Reverberation Time (RT), and Sound Pressure Level (SPL) are the three acoustic variables of the study. A total number of 15 historical mosques in Tabriz are divided into three large, medium, and small volume categories and five form categories have been tested. The reference of the study is ISO3382-1 and ISO3382-2 and the measurements were made with B&K equipment. In addition to the direct achievements, the results have been adapted to international standards and show that the acoustic situation in the historical mosques of Tabriz, regardless of their volume and form, produces sound in the range of 60 to 90 phones, and in terms of RT, have the suitable design from the volume point of view, but the lack of carpet flooring in some of them has increased the RT. The background noise in these examples is less than NC-25, which provides a quiet space for the user and provides the necessary concentration for individual worship.

Paying attention to the sound quality of mosques is one of the architectural fundamentals of Islamic societies because the mosque is the most prominent ritual place of Islam, and speech and hearing are considered its main characteristics. In this research, the analysis of the most effective form in optimal sound quality was defined as the primary goal, and for this purpose, the historical mosques of Tabriz city were subjected to field analysis. The initial analysis of the samples from the perspective of the variables affecting the acoustics led to the selection of 15 samples in three volume categories and five form groups, in which the selected standards for measurement are 3382-1 and 3382-2, and the measurement equipment are the 2260 B&K investigator and the SINUS Acoustic Camera. Among the acoustic variables, Background Noise, Sound Pressure Level, and Reverberation Time were analyzed, and the results of field measurement led to the framework becoming the final goal of the study. The results of this study show that acoustic behavior in samples regardless of their size and form is almost similar, which is due to the components such as materials and their implementation, as well as the overall formal frame within mosques, which were considered the same to reduce the interventional variables. The second achievement, which is the result of a visual data collection of the quality of sound playback, identifies the mentioned components and shows that the reflection and propagation of sound in selected mosques are from architectural elements that are common in all samples and form the overall frame of space. These two achievements framed the final goal of the study in the form of determining acoustic identification for historical mosques in Tabriz.  The final result of this study is the analysis of data in MATLAB software which extracts the Background Noise, Sound Pressure Level, and Reverberation Time equation based on frequency in Tabriz historical mosques and spaces with a similar model.

In this study, a novel simple strategy is proposed to choose and accommodate an airfoil based on the effects of airfoil type and plan-form shape on the flight performance of a micro air vehicle. In this strategy, after defining flight mission, the weight of the micro air vehicle is estimated and then, aerodynamic parameters and thrust force are calculated. In the next step, some different plan-forms and airfoils are investigated to be selected for decreasing the stall region in high attack anglesby open source software named XFLR5. Having calculated the aerodynamic center, the pitching moment needed to stabilize the micro air vehicle is computed. Due to the static margin, the airfoil camber line is changed to stabilize the micro air vehicle and then, its thickness is improved to reach to a high aerodynamic characteristic. To evaluate the software results, some flight tests are performed which then compared to the software results that show a good agreement. Finally, some adjustments and improvements are made on the micro air vehicle and then, its performance is obtained by the flight tests. The flight test results show it has an excellent aerodynamic performance, stability and maneuverability.