seyed mohammadjavad razavi

In this article, a harmonic generator based on klystron is presented, whose input signal is in Ka band and its amplified output signal is in W band. Harmonic generator design is based on Ka-band klystron, which reduces the electron beam current density in the interaction region, reduces the cathode density in the electron gun, and reduces the DC magnetic field required for electron beam convergence. Reducing the mentioned parameters reduces the challenges and complications related to the construction and increases the possibility of achieving high powers in the W band. One of the challenges of harmonic generators is their low efficiency, which has been tried to increase the electron efficiency by using the core oscillation method, which is one of the new methods for increasing the efficiency of klystron amplifiers. The designed harmonic generator structure consists of four Ka band cavity and one W band cavities. The design is done using AJDisk software and a indigenous code. The designed structure is simulated using the PIC studio of CST software. RF output power in W band (93.9 GHz frequency) is 6.4 kW with 16% efficiency. The input frequency is in the Ka band (31.3 GHz frequency). The gain of this device, which is equivalent to the ratio of output power to input power, is 53.9 dB. Extended interaction cavities have been used to reduce the voltage on the gap of the output cavity that prevents the RF breakdown

The accumulation and discharge of static electricity on the body of an aircraft in flight is inevitable which leads to interference in communication, Radar, and localizing systems of the aircraft. One of the more applicable and effective methods against this phenomenon is using a null-field static discharger. In this article, the amount of charging current injected into the airfoil has been calculated with empirical formulas. With the electrical field transient analysis on the aircraft body, the points that reach the corona threshold beforehand have been adopted as the discharger mounting areas. By implementing the structure of the null-field static discharger in the software and mounting it in the adopted points, the corona noise is reduced by 32 dB. The simulation results are justified by the experimental results of the references.

Due to fluid movement in fuel pipes and tanks, the electric charge will emerge in the fluid and its common surface with the pipes. As these charges become discharged the tanks and pipes are threatened; because the discharge energy becomes more than the lowest required energy of the fuel explosion and can lead to the fuel flaming and the explosion of tanks and tubes. In this article, the effect of the conductive and insulator pipes, the fluid velocity, and the pipe radius in the production of electric charge have been analyzed and studied. Always, in the calm fluid current, the produced electric charge is lesser than the turbulent fluid current counterparts. With more velocity of the fluid, the turbulent will become more occurred The results show that in the state of calm flow, the generated electric current is almost 250 dBA lower than the turbulent flow. Studies on the tanks during fueling show that accumulated electric charge has its maximum at the central axis and the charge is increasing with the filling of the tank..

The purpose of the present study is to design of the economic valuation model of Iranian basketball clubs was a choice experiment approach.

This study is analytical and descriptive. The statistical population of the study included four groups of faculty members, club managers, coaches and experts and, basketball veterans. Then, from each group according to the existing population, the sample was selected by a proportional distribution method. Therefore, in this study, 85 people were selected as a sample, which included 19 faculty members, 11 club managers, 23 coaches and, 32 basketball experts and veterans, respectively. For statistical analysis and also to present the proposed model of intangible assets of Iran basketball Club, Chioce experiment test and conditional logit and STATA13 software were used.

The results of economic valuation showed six models for valuation. Based on comments provided by the experts, sport federation officials, and basketball champion league, the fourth pattern was more practical than the other ones. The factor bearing the most amount of value in this pattern was related to the fans of a club with an acceptance inclination index of WTA: 2130673014 Tomans and the most amount of value for the inclination to pay indices was related to awarding one’s shirt to the fans with WPT of 1984774741 Tomans.

Considering the results of the present study, it is suggested that sports officials and champion leagues use the suggested model nonmarket assets of basketball clubs.

This article presents a comprehensive step-by-step design and simulation process for a new multilayer monopulse antenna operating in the Ku frequency band. The antenna is designed to exhibit high gain, high efficiency, low sidelobe levels, and 45° linear polarization. The radiating element employs a microstrip antenna with waveguide feeding. To mitigate coupling between the radiation elements in the array structure, a metal cavity is strategically placed between the feeding network and the radiation patch. Additionally, a sub-array is designed to simplify the feeding network, incorporating a cavity power divider and feeding slots between the layers to reduce the antenna's overall height. A two-dimensional Chebyshev distribution is employed to design a 1 to 48 power divider. Through simulation, the antenna demonstrates an 11% bandwidth, 38.4 dB gain, sidelobe levels better than 19 dB in both planes, an approximate beam width of 2.4 degrees at the center frequency, efficiency higher than 86%, and a null depth better than -38 dB. The radiation patterns exhibit good symmetry in both the E and H planes. A one-twelfth scale model of the antenna is constructed, with measurement results showing excellent agreement with the simulation.

Operational sensitivities of military air craft, deterrent measures in aircraft design to prevent the accumulation of static charge on the surface of the aircraft or Electrostatic Discharge, is very necessary and important. These include antistatic coatings, flame spraying, the use of carbon fiber composites and nanocomposites in aircraft fuselage design, and electrostatic dischargers. The aim of this study was to investigate, simulate and compare the effect of electrostatic discharge (ESD) in military aircraft with all-metal, all-composite body and the combined state of several structures. In this paper, by selecting the military Aircraft body of composite, metal and combined mode, the effects and surface of induced electric field, surface currents due to electrostatic flux and Radiation electromagnetic fields from the transient state of surface current will be compared and examined in different parts of the military air craft, including: radar system, cabin and electronic telecommunication systems, internal and external fuel tank.

One of the cases of crimes against individuals is the stalking, which is actually a crime against one's mental freedom. The various instances of this criminal behavior have been explicitly stated in the laws of many countries and have been considered as a misdemeanor in most cases. Iranian criminal law is silent in this respect. The existence of this behavior against individuals in the community, as well as its expansion in the real world and also through cyberspace, in addition to offenses and damages caused by such behaviors, including the fear of insecurity in citizens, necessitates legislative intervention in this regard. The present article attempts to make a comparative analysis of this behavior and its elements, including the legal, mens rea and actus Reus of this crime, by using a descriptive-analytic method. Then, practical and comprehensive suggestions have been presented to the legislator for removing this legal silence.

Electrostatic discharge(ESD) is a highly repeatable problem with harmful effects. These effects include destroying computer systems memory, damaging the electronic circuits, electromagnetic interference on the airplane radar and avionics systems, and destroying the surfaces. Knowing the places where electrostatic discharges have occurred in the airplane body can help in the airplane cost reduction for scanning and finding the resulting defects of ESD. Also, it informs the pilot and crews for example to know why communication and radar systems do not work correctly. So, it causes airplanes to be designed and fabricated safer. On this basis, in this article, the position of the electrostatic discharge in the cylindrical structure of the airplane has been obtained by the TDOA method. The accuracy of the estimation in the simulation is 9cm and in the measurement is 11cm.

The ionosphere, a crucial component of Earth's atmosphere, plays a pivotal role in facilitating radio communication. However, its inherent characteristics, such as the reflection and refraction of radio waves, are subject to instability, exhibiting sudden changes influenced by temporal and geographical factors. These fluctuations pose challenges for radar and communication systems reliant on the natural ionosphere, diminishing their reliability. Consequently, numerous studies have focused on inducing controllable alterations in ionospheric properties, including electron density, plasma frequency, and electron temperature. One prevalent method involves heating specific ionospheric regions using electromagnetic waves, offering a means to manipulate its characteristics deliberately. By implementing such controlled modifications, the inherent instability of the natural ionosphere can be mitigated. This paper presents the creation of an artificial ionized region, achieving an electron density of 108e/cm3, through a heating array with an Effective Radiated Power (ERP) of 153 dBW, situated at an altitude of 65 km. This artificial ionized zone enables controlled reflection of radio waves within the frequency range of 3-90 MHz, catering to radar and communication systems' requirements. The primary focus of this article is the analysis and investigation of the ionospheric heating process utilizing high-power electromagnetic waves emitted by heating antennas. Specifically, employing an analytical approach, the article delineates the calculation of requisite characteristics for the heating antennas to generate artificial ionized areas at varying altitudes.

Phase velocity and interaction impedance measurements on slow wave structures are especially important in the microwave tubes industry. Among the methods available for measuring the phase velocity and interaction impedance, non-resonant perturbation method is simple yet accurate and applicable. In this paper, the correctness of this method for helical slow wave structure is investigated with simulation and analytical methods and based on it, a device is built that has the precision needed to move the perturber inside a slow wave structure. The results and measurement capabilities of this device have been demonstrated using simulations in CST software and analytical relationships.

Personal brand management is very necessary for both athletes and sports organizations. Therefore, with respect to the importance of personal brand for players, the purpose of this research is the explaining the model of the impact of critical thinking and interpersonal communication skills on the personal brand promotion in Iranian football league players.

The research community of this study was 288 players of the Iranian football league (Persian Gulf Cup). According to Krejcie and Morgan table, the sample size was estimated to be 165 players. This study is a causal research and by survey method was conducted. The questionnaires of critical thinking, interpersonal communication skills and personal brand are the main tools of variables measuring. The content validity of the research tool was confirmed by 10 experts and sport management professors, and the reliability of these questionnaires was also confirmed using Cronbach's alpha coefficient, being 0.88, 0.86 and 0.92, respectively.

The results of data analysis by using partial least squares (PLS) method, showed that critical thinking had significant effect on personal brand and interpersonal communication skills of Iranian football league players. Also, interpersonal communication skills had significant effect on the personal brand of Iranian football league players.

So, we can conclude that by using the appropriate and desirable way of critical thinking in the Iranian football league players, we will see development and promotion of interpersonal communication skills and personal brand in the Iranian football league players.

This work aims to identify and prioritize the factors involved in the human capital (HC) development in Iran's sports production firms using the multi-criteria analysis and the Copland's approach. This work follows a practical application and uses a descriptive-survey design. The research population of this work consists of 107 experts from the Iran's sports production firms. The sampling method is purposive.

At the company level, human capital (HC) should be considered as a resource that can be used in order to achieve a sustainable competitive advantage. Based on the HC theory, it is the individuals with different knowledge and skills that create an economic value. There is a convincing evidence that the HC knowledge is essential for the discovery, creation, and exploitation of corporate entrepreneurial opportunities. Therefore, the level of knowledge, experience, and merit of the managers and employees in a company helps to provide HC through formal education, business experience, practical learning, and informal education.

The data was collected using a research-made questionnaire. After confirming the content validity of the questionnaire using the opinions of 10 experts in the field of sport management, the reliability of the questionnaire was obtained using the Cronbach's alpha coefficient (α = 0.89). The factors involved were initially identified and then ranked using various models of multi-attribute decision-making with excel2013 and expert choice11. As the results obtained from the above-mentioned models did not conform to each other in some cases, an integrated model called the Copland approach was used in order to reach a general consensus in ranking the obstacles to the factors involved in the HC development.

The ranking results obtained from the Copland technique revealed that the three main factors involved in the human capital development have attracted the human resources with a high level of expertise and knowledge, creating and using an integrated knowledge management system, and using experienced managers and staff with experience, respectively. According to the results of this research work, using the correct factors provided from the development of HC such as the use of skilled, experienced, and knowledgeable human resources, we will see more efficiency of this valuable resource in the Iran's sports production firms by improving the performance of these companies to provide the necessary ground for the further improvement of the Iranian sports industry.

Sport financial sponsorship can offer sport marketers the opportunities to address new audiences and enhance brand equity and companies’ performance.

The purpose of the current study was to develop a model for the role of sport financial sponsorship on brand equity of Yazd ceramic and tile companies.

The current study was conducted with a survey method. Standard sport financial sponsorship and brand equity questionnaires were used as measurement tools to assess the subjects. Data analysis was conducted both descriptively and inferentially.

The results of the data analysis revealed that sport financial sponsorship has a significant positive effect on brand equity, and brand equity, in turn, has a significant positive impact on companies’ performance.

It seems that due to the nature of the exercise and its effectiveness in promoting the sponsor company, it has a positive influence on developing brand equity of companies. It was found that proper behavior of members of the board of directors of companies towards their brand facilitates this process.

To effectively response to environmental changes and gain a competitive advantage, sports manufacturing companies should invest in human capital.

The study aimed at examining the effects of human capital on technological innovation capabilities in Iranian sports manufacturing companies.

Conducted applied research and the survey. Data were collected using standard questionnaires in human capital and technological innovation capabilities. The reliability of the questionnaires was 0.81 and 0.85, respectively. The study was conducted on 546 employees from 77 sports manufacturing companies. To evaluate the research hypotheses, structural equation modeling based on partial least-squares method was used.

The study results indicated a significant impact of brand associations on brand equity and brand citizenship behavior; human capital also had a significant impact on technological innovation capabilities. According to ranking results, the three main features of the human capital of sports manufacturing companies respectively were skills and expertise, knowledge, and experience.

The main factors can significantly affect the development of human capital and technological innovation capabilities in Iranian sports manufacturing companies.

ranking of university sports teams participating in Olympiad games done based on total earned scores, but should be noted that to achieve competition outputs (the total number of scores won in the tournament) are possible only in the context of utilization of inputs and using appropriate processes and for precise, regular and targeted evaluation, smaller inputs should be included along with more outputs in the evaluation models. In this research, we try to evaluate the performance of sports teams participating in the 13th Olympiad culture and sport in Iran by using one of the nonparametric methods of operations research called Data Envelopment Analysis (DEA). The model in the paper considers two input (population of a university student and head-money of universities) and two outputs (sum of sports team score and number of university athletes) with different weight and importance for performance assessment. The results of this model for boys sports teams showed that of the 24 universities participating in the Olympiad games, 10 universities get maximum Efficiency also The results of this model for girls sports teams showed that of the 23 universities participating in the Olympiad games, 8 universities get maximum Efficiency.

Exercise is an organized phenomenon that can be evaluated in various aspects. An important aspect of it is its universal and sense of public port, considering the important role of public sport on the health, social and economic aspects of the society; it was aimd to perform the study to analyze the participation motivation of male and female in Yazd City in the universal sports. Methods: The statistical population consisted of 486152 participants between male and female above 15 years age in the Yazd City; obtained by the census data of 2011, the selected sample size was 400 people. This research was based on applied and field survey method. The data were quantitatively collected using questionnaire. After confirming the content validity of the questionnaire by the opinions of ten experts in the field of sport management, the reliability of the questionnaire was obtained using Cronbach's alpha coefficient. In this study, the strategies to motivate the participation of male and female of Yazd City in the universal sport in a qualitative way the data were analyzed using SPSS 16 software. The results showed that the main factors influencing the motivation of participation of male and female in sports in Yazd City was management, cultural and preventive and therapeutic factors, respectively. Therefore, it is necessary to adopt regular planning by sports managers and to use mass media for encouraging people to participate in universal sports, and to develop a culture among people of Yazd City to participate in the daily life sports activity

The present study was conducted aiming at the explication of market entry (West Asian Markets) mode strategies via resource-based and institutional influences on the Iranian body building equipment industry. Current research is applied in terms of method and has been done by means of survey. The statistic population includes all senior managers and employees of Iranian producing factories and export-import companies of body building equipment in 2017 (192 cases). The PPS method was used for sampling. The research instrument includes the questionnaire of examining market entry mode strategies via resource-based and institutional influences of Zovo Kavogil (1996) and the questionnaire of company performance of Okas et al. (2012). Structural equation modeling technique was used to analyze the data using the software PLS and SPSS. Based on the results of data analysis, resource-based characteristics and environment-based features have a significant effect on the selection of market entry strategies. In addition, the strategies selected to penetrate the target market have a significant and positive effect on the company's performance. As a result, there are two equal and unequal modes of entry into the new market; companies seeking to enter the unequal state of the target market should have a dual view on their strategies: 1. Short-range vision (using strategies related to environmental resources Infiltration into the target market. 2. Long-term vision (considering organizational influences on the type of market entry choice).

The aim of this study was to prioritize the barriers to the support of Yazd ceramic and tile companies for soccer clubs. This study was application and survey. The statistical population consisted of 352 members of the board of directors of 65 Yazd ceramic and tile companies. According to the Morgan Table, the sample size was determined to be 176 subjects. The barriers to the support for soccer clubs were identified using interviews of the sample and then the data were quantitative collected using a researcher-made questionnaire. The validity of the questionnaire was confirmed by 10 sport management professors and the reliability was calculated using Cronbach's alpha coefficient (α=0.87). Data were analyzed by both descriptive and inferential statistics. In this study, firstly, the barriers to the support of Yazd ceramic and tile companies for soccer clubs were identified and then ranked based on the Analytic Hierarchy Process (AHP). The ranking results showed that the three main reasons why Yazd ceramic and tile companies did not support soccer clubs were governmental (6 barriers), financial (5 barriers) and management (6 barriers) respectively. Thus, it will be useful to pay attention to these existing barriers to realize the support for soccer clubs.

The purpose of this study was identifying and modeling of the development guidelines of sports for all among the female students in University of Birjand. The statistical population of this research consisted of 8246 participants among the female students in university of Birjand; the sample size with Cochran formula was 370 people. This research is a survey-based study and it follows a practical application. The data was quantitatively collected using a research-made questionnaire. After confirming the content validity of the questionnaire by the opinions of eight experts in the field of sport management, the reliability of the questionnaire was obtained using Cronbach's alpha coefficient. In this study, the University of Birjand solutions to the female students participation in sport for all identification; and then measuring Structural equation modeling and Friedman test. Data analyses with PLS & SPSS22 software. The results showed that the main factors in girl Students participation in sport for all were economic solutions, management, cultural Infrastructure and facilities, research and education. Therefore, it is necessary to institutionalize the culture of sport, recreation and sports programs and sponsorship of sport for all students trying in develop sport among the female students in university of Birjand.

This study aimed at explaining the role of effective strategies on developing human resources, organizational entrepreneurship and organizational development from the viewpoints of employees of Sport and Youth Ministry. According to the information from Information Department of Sport and Youth Ministry of Islamic Republic of Iran in 2016, the statistical population consisted of 850 employees. The sample size was considered 265 subjects based on Krejcie and Morgan Table. This study was application and survey.  Strategies in the Development of Human Resources Questionnaire (Mirsepasi et al., 2010) and Organizational Entrepreneurship and Organizational Development Questionnaires (Talebpour&Razavi, 2016) were used. Their reliability were calculated as 0.87, 0.91 and 0.82 respectively. To test the conceptual model, structural equation modeling based on partial least squares method using PLS statistical software was applied. The results showed that strategies of the development of human resources had a significant effect on organizational entrepreneurship and organizational development. Also, organizational entrepreneurship had a significant effect on organizational development. According to those factors affecting the development of human resources and the promotion of organizational entrepreneurship, employees were an effective factor in promoting organizational development.

This study aims was to compilation the role knowledge management on the organizational entrepreneurship and employee empowerment in department of youth and sport of yazd. According to the information department of youth and sport of yazd, in the 2016 study sample consisted of 144 employees. The sample size was considered 105 number. conducted applied research and the survey. measuring was with, Standard questionnaires role knowledge management (Dilmaghani & Namvar, 2017), organizational entrepreneurship and employee empowerment (Talebpour & Razavi, 2016). The reliability of questionnaires, respectively, 0/89, 0/91 and 0/84 respectively. For the test a research hypotheses, structural equation modeling based on partial least squares method using statistical software PLS. the result showed there is a significant impact of knowledge management on organizational entrepreneurship and employee empowerment and there is a significant impact of employee empowerment on organizational entrepreneurship. It seams pay attention to knowledge management and promotion of employee empowerment in the organization was a contributing factor in the promotion of organizational entrepreneurship.

This study aimed at brand associations and brand identity with an emphasis on the mediating role of brand citizenship behavior and providing a structural model of brand equity enhancement from the viewpoint of staff in Sport and Youth general office of Khorasan Razavi. This study was applied and survey. Researcher-made questionnaires of brand associations and brand citizenship behavior and standard questionnaires of brand identity and brand equity were used. Their reliability was 0.85, 0.82, 0.79 and 0.81 respectively. According to the information of Personnel Department of Sport and Youth general office in Khorasan Razavi, the population consisted of 123 employees in 2016. The sample equaled the population. To test the research model, structural equation modeling based on partial least squares method was used. The results showed that brand associations had a significant effect on brand equity and brand citizenship behavior. Also, brand identity had a significant effect on brand equity and brand citizenship behavior. Therefore, attention to maintain and develop brand identity and favorable brand associations in staff is a factor which influences brand equity enhancement in the organization.

The aim of the current study was to identify and prioritize barriers to the development of swimming in Kerman province according to Analytic Hierarchy Process (AHP). Research method was applied and in terms of data collection, it was a field study. The population consisted of 101 managers, coaches and athletes with swimming history in Kerman province. A researcher-made questionnaire about barriers of swimming development in Kerman province was designed after interviews with sport experts and managers. The results showed that factors such as lack of importance to swimming in schools, lack of efficient planners and proper planning at macro level, failure to attract sponsors to financially support swimming, lack of support from the media to promote swimming and lack of standard training and competition pools were considered as important internal barriers to the development of swimming in Kerman province. Also, among six main factors, management and planning barriers were taken into consideration as the main factor hindering the development of swimming. It seems that swimming can improve in Kerman province through proper planning, employing qualified individuals for talent identification of elementary school children, building a relationship with private and state organizations for financial support, operating competitions and inviting the media to encourage people to participate in swimming and running different meetings with officials of Sport and Youth Organization and subsequently the Ministry of Sport and Youth to construct standard water facilities.

This study aims to recognize and ultimately prioritize barriers to the privatization of soccer industry in Iran using the integrated approach of multi-criteria analysis and Coplands; this investigation is also based on the opinions of experts and informing sport policy makers about strengths and weaknesses of the privatization of soccer industry in Iran as well as the barriers to do so. This research is a survey-based study and it follows a practical application. The data was quantitatively collected using a research-made questionnaire. After confirming the content validity of the questionnaire by the opinions of 10 experts in the field of sport management. Both descriptive and inferential data analyses were conducted. In this study, barriers to the privatization of soccer industry in Iran were initially identified and then ranked using various models of multi-attribute decision making (MADM). As the results obtained from the above-mentioned models did not conform to each other in some cases, an integrated model called Copland approach was used to reach a general consensus in ranking obstacles to the privatization of soccer clubs in Iran. Ranking results obtained from Copland technique revealed that the three main barriers to the privatization of soccer industry in Iran are lack of proper planning for privatization, lack of television broadcasting right for soccer industry in Iran and lack of appropriate infrastructure for privatization of soccer industry in this country, respectively. Therefore, paying attention to the existing obstacles can be very useful in the realization of soccer industry privatization in Iran.

This study aimed to Identify and prioritize barriers to the development of football in the Yazd province. This study used a descriptive survey. The study sample consisted of 68 of managers, coaches and athletes in the sport of football in the Yazd province. This research is a survey-based study and it follows a practical application. The data was collected using a research-made questionnaire of barriers to the development of football in the Yazd province. After confirming the content validity of the questionnaire by the opinions of 10 experts in the field of sport management, the reliability of the questionnaire was obtained using Cronbach's alpha coefficient (α=0.82). Both descriptive and inferential data analyses were conducted. In this study barriers to the development of football in the Yazd province were initially identified and then ranked using various models of multi-attribute decision making. Ranking results from Kopland technique, showed the third leading cause were Failure to plan for barriers to the development of football, Lack of qualified personnel in managerial positions Yazd Soccer & Lack of attention to the talent and teams. It seems that it can be possible to step towards soccer improvement in Yazd province with proper planning, the use of qualified individuals for the talent identification, build a relationship with public organizations for support of financial sponsors.