Promotion in Iran`s Football Pro-League: Important but Weak!

( Mehrdad Estiri ),( Mohammad Haghighi ),( Reza Mohammadkazemi ),( Hamzeh Rayej ),( Mohammad Jahed ) 체육과학연구원 2010 International Journal of Applied Sports Sciences Vol.22 No.1

The present research attempts to clarify and extend the conceptualization and measurement of promotional activities in Iran`s football professional league. Based on this, this research was conducted to recognize the promotion activities in Iran`s football League and perform an analysis of the current situation of this league in order to compare it with other Asian Leagues such as Japan and South Korea. The review of the Sport marketing and Sport Promotion literatures and the findings from qualitative and quantitative studies conducted by the authors reveal that, promotional activities in Iran`s football League consisted of 14 factors. The revealed results regarding Iran`s football league position, have shown that Iran`s league compared with Japanese and South Korean leagues was not in a desirable position. We conclude the paper with a summary of the main results of the study and directions for future research.

Detection and Tracking of Screen Golf Ball based on Image Segmentation

Mehrdad Ahmadi(메흐다드 아마디),K. W. Ko(고국원),D. H. Kim(김동현) 한국정밀공학회 2014 한국정밀공학회 학술발표대회 논문집 Vol.2014 No.10월

Numerical Optimization for the Cascade of a Transonic Axial Turbine via Genetic Algorithm

Mehrdad Nafar-Sefiddashti,Mahdi Nili-Ahmadabadi,Kyung Chun Kim 대한기계학회 2019 대한기계학회 춘추학술대회 Vol.2019 No.11

This study presents a numerical optimization method for the cascade of an axial turbine. The optimization of a turbine blade is in fact the redesign of the existing blade by coupling a CFD flow solver with an optimization algorithm in order to achieve better performance. Genetic algorithm was used as the optimization algorithm. The CIRCLE method, as a design method with continuous surface curvature distribution, parameterized the geometry of the blades by 33 geometrical parameters. The cost function was to reduce the total pressure loss by considering the constraints on the load factor, blade cross-section, mass flow rate and outlet flow angle. Finally, the genetic algorithm, the geometry parameterization algorithm, computational grid generator and CFD flow solver were automatically coupled to optimize a transonic stator blade row.

Modeling of Belt-Pulley and Flexible Coupling Effects on Submarine Driven System Electrical Motors

Mehrdad Jafarboland,Mahmoud Zadehbagheri 전력전자학회 2011 JOURNAL OF POWER ELECTRONICS Vol.11 No.3

Nowadays numerous research projects are being conducted in the field of electric motors. Non-modeling of flexible connections such as couplings and the belt-pulley do not show some real behaviors. With an increase in the number of connections and drive factors, these Non-modeled modes become more important. The coupling of two electric motors, instead of one motor, in submarine propeller force is an obvious example which shows that Non-modeled vibration modes caused by flexible connections can disturb controller operation and make undesirable vibrations in the submarine body. In this paper a dynamic model of flexible connections and a completed dynamic model of two different coupled electric models is presented. A robust controller for the completed model is also amended so that the two controlling targets of a desired speed adjustment and an appropriate load division between the two motors with sufficient accuracy are achieved.

Analysis of an LCLC Resonant Converter with a Capacitive Output Filter

Mehrdad Jafarboland 전력전자학회 2011 JOURNAL OF POWER ELECTRONICS Vol.11 No.5

This paper presents an analysis of a 4th order LCLC resonant converter with a capacitive output filter using the state-space approach. The analysis of the converter shows that there are four intervals in a half period. In each interval, the state-space equations are obtained. Due to the soft switching of the converter, an exact equation for the Zero Voltage Switching (ZVS) time and the maximum dead time of the inverter switches are presented. The simulation and experimental results obtained from a 10kv, 370w prototype confirm the validity of the theoretical analysis.

A comparative study of ectoparasites occurrence between grass carp and silver carp in guilan province culture ponds, Iran

( Mehrdad Asgharnia ),( Mohaddes Ghasemi ) 한국어병학회 2021 한국어병학회지 Vol.34 No.2

Parasitic infection is among the most common problems for carp cultivation. They are also important for the principal entrance of other hazardous infections as well. This study was carried out for determining of parasitic fauna of two major carp known as silver and grass carp with the comparison of prevalence value and intensity rate of parasites among them, alongside the relationship between the biometric characteristics and host sex with the infection level. For this purpose, a total of 94 fish samples were caught randomly using a fishing net, from Guilan ponds during spring and summer of the year 2018 and transported alive to the laboratory. Upon arriving, the biometric characteristics and genus of each carp were measured individually. Specimens were then acquired from the skin, gills, and eyes of the carp and examined according to standard parasitology methods. Recovered parasites were observed under a light microscope and then fixed for identification. As the result, the occurrence and intensity in the higher length group were comparatively greater than the lower one. Also, the prevalence and intensity of total parasites in male carp were higher than in females. In this research, Dactylogyrus hypophthalmichthys and Dactylogyrus aristhichtys were observed in silver carp and Dactylogyrus lamellatus was detected in grass carp. In the paper below, we found that the host specificity varies in different species of Dactylogyrus isolated from grass carp and silver carp.

Experimental study of effects of circular-cross-section riblets on the aerodynamic performance of Risø airfoil at transient flow regime

Mehrdad Nafar Sefiddashti,Mahdi Nili-Ahmadabadi,Behnam Saeedi Rizi 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.2

New drag reduction methods have received much attention due to the importance of drag reduction in airplanes and wind turbines. One of the ways for drag reduction is the use of riblets. We investigated the effects of riblets on the aerodynamic performance of the Risø airfoil quantitatively. By installing a load cell and using the one-sided force measurement method, the drag and lift coefficients of the Risø airfoil were measured in two modes: With and without riblets at three different arrangements. The shape of riblets is a circularcross-section and the ratio of riblets’ diameter to the airfoil chord is equal to 0.005. The tests were carried out in transient flow regime (Two Reynolds numbers of 2.02×10 5 and 1.4×10 5 ), and at attack angles from 0 to 20 degrees. The results indicate that the extent of the riblets effect on the aerodynamic performance of the airfoil depends on the angle of attack, Reynolds number, and arrangement of the riblets on the airfoil. The maximum drag reduction at the Reynolds numbers of 2.02×10 5 and 1.4×10 5 is about 29.7 % and 54 %, respectively, that occurs at an attack angle of 7 degrees for both two Reynolds numbers .

The Assessment of Tourism carrying Capacity of Historical city : A case study of Borujerd city

Mehrdad karami,Mehdi Modiri,Mohanna Nikbin 세계문화관광학회 2011 Conference Proceedings Vol.12 No.-

In order to control the pressure loaded on the tourist sources of the historic city and prevent the destructive effects of the tourism development it is intended to specify the tourism carrying capacity of the Historic city of Borujerd. the study was intended to measure tourism carrying capacity of Borujerd city. In the study on the one hand we engaged in measuring tourism carrying capacity of the city. The study indicated that tourist influx into Borujerd took place in late winter and early spring. The volume of incomer tourists outnumbers the current carrying capacity of the city. Taken its defined carrying capacity into account the city's tourism development trend was unstable. In view of the approach based on the theory of cycles tourism in Borujerd had almost been saturated inharmoniously and incompletely without supplying the required infrastructures for the tourists. Especially in the first quarter of the year the number of tourists meets its peak and unveils its negative effects on the environment at different economic social and environmental aspects.

Power spectral density method performance in detecting damages by chloride attack on coastal RC bridge

Mehrdad Hadizadeh-Bazaz,Ignacio J. Navarro,Víctor Yepes 국제구조공학회 2023 Structural Engineering and Mechanics, An Int'l Jou Vol.85 No.2

The deterioration caused by chloride penetration and carbonation plays a significant role in a concrete structure in a marine environment. The chloride corrosion in some marine concrete structures is invisible but can be dangerous in a sudden collapse. Therefore, as a novelty, this research investigates the ability of a non-destructive damage detection method named the Power Spectral Density (PSD) to diagnose damages caused only by chloride ions in concrete structures. Furthermore, the accuracy of this method in estimating the amount of annual damage caused by chloride in various parts and positions exposed to seawater was investigated. For this purpose, the RC Arosa bridge in Spain, which connects the island to the mainland via seawater, was numerically modeled and analyzed. As the first step, each element’s bridge position was calculated, along with the chloride corrosion percentage in the reinforcements. The next step predicted the existence, location, and timing of damage to the entire concrete part of the bridge based on the amount of rebar corrosion each year. The PSD method was used to monitor the annual loss of reinforcement cross-section area, changes in dynamic characteristics such as stiffness and mass, and each year of the bridge structure’s life using sensitivity equations and the linear least squares algorithm. This study showed that using different approaches to the PSD method based on rebar chloride corrosion and assuming 10% errors in software analysis can help predict the location and almost exact amount of damage zones over time.

Brain Tumor Detection Using Wavelet Transform and Convolution Neural Network in Magnetic Resonance Imaging

Mehrdad Dadgostar,Sahar Solaymanpour,Zahra Einalou,Hamidreza Hosseinzadeh 서울대학교 인지과학연구소 2022 Journal of Cognitive Science Vol.23 No.1

The brain tumor is the growth of an abnormal mass in the brain which may be malignant or benign. Misdiagnosis of different types of brain tumors reduces the patients' chances of survival. In the last years, efforts have been made to automate the present process for clinical and research reasons. For this purpose, machine learning methods were highly considered for a long time. In this paper, we presented a method for classification of brain tumors from magnetic resonance images using a convolutional neural network and two-level discrete wavelet transform algorithm. The BRATS 2013 dataset contains FLAIR, T1, T1c and T2 images of 20 patients with high-grade glioma, and ten patients with low-grade glioma were used in this investigation. This study aimed to classify the data into two classes of high-grade glioma and low-grade glioma by convolution neural network using a two-level wavelet transform algorithm on images. The Image wavelet coefficients contain more information than the original images, thus increasing the network performance. All the experiments were performed on the main dataset and two synthetic datasets with 60 and 300 data. The highest classification accuracy is obtained for T1 images in all three sets of 30, 60 and 300 data that were 86.25%, 94.58%, and 95.86%, respectively.