List of Articles مخابرات

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  1 - Design of Secure Communication System by Use of Synchronization of Chaotic Systems
  Mohammad nikkhoo masoud shafiee koorosh kiani
  In this paper, the concept of secure synchronization of chaotic systems using adaptive and robust techniques , has been discussed and then a new secure communication scheme, based on secure synchronization of a general class of chaotic systems called Generalized Lorenz More

  In this paper, the concept of secure synchronization of chaotic systems using adaptive and robust techniques , has been discussed and then a new secure communication scheme, based on secure synchronization of a general class of chaotic systems called Generalized Lorenz System, are presented. This communication scheme is combination of conventional cryptographic methods and chaotic modulation method. Analytical and simulation results using sine and voice signal and with unknown constant propagation delay between transmitter and receiver , have been presented. Also, robustness of this scheme against Gaussian channel noise with variance of , and security analysis of this communication system from brute-force viewpoint has been evaluated. By using this communication scheme, the very great key length has been obtained. Manuscript profile
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  2 - Polar Diagram of Points with Moving Pole
  Bahram Sadeghi Bigham fateme rabani
  Polar diagram is a generalization of Voronoi diagram in which the angle is used as the metric. This Problem has many applications in visibility, image Processing, telecommunication, antenna, and Path Planning Problems. In recent years two kinds of Polar diagram have bee More

  Polar diagram is a generalization of Voronoi diagram in which the angle is used as the metric. This Problem has many applications in visibility, image Processing, telecommunication, antenna, and Path Planning Problems. In recent years two kinds of Polar diagram have been proposed and appropriate algorithm have been Presented for some types of sites. Also, some algorithms has presented for kinetic data and dynamic states. In this Paper, it is assumed that the Pole is moving and an algorithm is presented that updates near Pole Polar diagram of sites with moving pole efficiently and in a sub linear time. In this approach, the Preprocessing time is 〖O(n^4 log〗_2⁡〖n)〗 and updating time for diagram with each successive movement is 〖 O(log〗_2⁡〖n +k)〗 that k is the number of sites in region T which its site’s regions may be changed Manuscript profile
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  3 - Increasing the lifetime of underwater acoustic sensor networks by optimal relay node placement
  zahra mihamadi mohadeseh soleimanpour daryush avasimoghaddam Siamak Talebi
  Underwater acoustic sensor networks (UASNs) have gained growing importance due to their desirable features and wide spread practical applications in many communication fields. Due to the high cost of underwater sensor nodes as well as implementation complexity, increasi More

  Underwater acoustic sensor networks (UASNs) have gained growing importance due to their desirable features and wide spread practical applications in many communication fields. Due to the high cost of underwater sensor nodes as well as implementation complexity, increasing the lifetime of UASNs is an important issue. Although relay nodes have an important role in reducing the transmission distance and energy consumption. But the efficient RNP (Relay Node Placement) to avoid the critical sensor nodes' elimination is the main problem, i.e., to preserve the connected network. For this aim this paper presents an innovative solution called an Efficient Relay node Setting (ERS) algorithm, which involves formulating the Relay Node Placement (RNP) as a non-convex optimization problem. Actually, due to the Difference Convex (DC) constraints the proposed RNP problem is a non-convex problem and finding an optimal solution is complicated. However, a novel transformation can be applied to DC constraints which converts the problem into its convex programming equivalent. Application of the convex programming offers the advantage of readily computing a global optimal solution. Simulation results confirm the superiority of the proposed scheme over the competing RA method in terms of network lifetime and efficiency. Manuscript profile
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  4 - The investigation of the Impact of Employee Empowerment on Knowledge Sharing in Post and Telecommunication Company (PTC) of Shiraz city
  Saeed  Saeeda Ardakani Mehdi Tajpour Elahe Hosseini
  the present study aimed to investigate the effect of employee empowerment on knowledge sharing in Post and Telecommunication Company in Shiraz city. The statistical population consists of 210 people of all employees working in the PTC of Shiraz city. The sample size was More

  the present study aimed to investigate the effect of employee empowerment on knowledge sharing in Post and Telecommunication Company in Shiraz city. The statistical population consists of 210 people of all employees working in the PTC of Shiraz city. The sample size was determined 132 people according to Morgan table. Since this research discovers new facts and gives immediate answer to a question, it can be classified as an applied research by purpose. In addition, the Methodology approach to research is of descriptive-survey type that a standard questionnaire which its reliability was confirmed by Cronbach's alpha coefficient (0.799) was used to collect the date. The smart PLS software was employed to analyze the data. The results showed that knowledge empowerment of employees on knowledge sharing has a significant impact on knowledge. Manuscript profile
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  5 - Modeling and Analysis of Tower Protection Performance in Order to Coordinate with Environmental Conditions Response and Security Constraint Unit Commitment
  M. Yahyaabadi A.  Sadoughi
  رIn this paper, effective parameters on lightning performance of communication tower are analyzed. The effect of communication tower height, Influence of weather conditions and adjacent structures are investigated. A 3-D numerical analysis model based on charge simulati More

  رIn this paper, effective parameters on lightning performance of communication tower are analyzed. The effect of communication tower height, Influence of weather conditions and adjacent structures are investigated. A 3-D numerical analysis model based on charge simulation method is applied to calculate the probability of shielding failure and to determine the number of direct lightning strokes to antenna. The communication tower, lightning rod, downward descending leader and upward leaders are modeled by different shapes of charges. For each of the numerous points of all the space above the tower and for different values of lightning current, downward lightning leader is considered to be initiated, and it is distributed step by step until final jump. The electric field around the grounded objects is calculated and upward leader inception criterion is checked in each step. If this criterion were approved for a point, an upward leader would be initiated from that point and then the distribution of upward leader would continue. Upward leaders might be initiated from more than one point but only one of them could strike to downward leader. This process will continue for different conditions and in every situation all the results are analyzed and evaluated. Manuscript profile
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  6 - Coordinated Fair Scheduling in LTE-Advanced Multi-Sector Cells
  M. Abiri Mehri Mehrjoo R. Abaspour Ghadi
  In this paper, we propose a coordinated fair scheduling (CFS) scheme for LTE-Advanced networks where the cells are equipped with multiple sector antennas. To enhance the network spectral efficiency and throughput, the sectors use the same frequency bands. However, to re More

  In this paper, we propose a coordinated fair scheduling (CFS) scheme for LTE-Advanced networks where the cells are equipped with multiple sector antennas. To enhance the network spectral efficiency and throughput, the sectors use the same frequency bands. However, to reduce the co-channel interference, the transmissions from the sectors to the users are coordinated. In other words, multiple sectors are allowed to transmit simultaneously, if the occurred co-channel interference is less than a threshold value. The scheduling scheme takes advantage of the user's diversity in space to transmit to the users with good channel conditions while maintaining fairness among the users using the alpha-fair criterion. Furthermore, a heuristic approach is proposed to reduce the computational complexity of the scheduling scheme. The performance of the proposed CFS scheme and the heuristic approach are evaluated using simulation results. The simulation results show that using coordinated fair scheduling improves system performance and increases cell throughput. Manuscript profile
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  7 - Wireless Powered Communication System Design with Nonlinear Energy Harvester
  مهرنوش  میرحاج مریم مسجدی محمدفرزان صباحی
  In this paper, a wireless powered communication network (WPCN) is considered, in which the hybrid access point (HAP) and the users are equipped with multiple antennas.In the downlink phase, an energy HAP transfers the energy signal to the users and in the uplink phase, More

  In this paper, a wireless powered communication network (WPCN) is considered, in which the hybrid access point (HAP) and the users are equipped with multiple antennas.In the downlink phase, an energy HAP transfers the energy signal to the users and in the uplink phase, users apply the harvested energy to transfer their information to the HAP using spatial division multiple access (SDMA) technology. By considering the nonlinear behavior of energy harvester in system design and aiming to maximize the sum of the rates, we propose an optimal method for designing energy pre-coding matrices, user information pre-coding matrices, and time devoted to the downlink and uplink phases. For this purpose, we rewrite the problem as a convex optimization problem by appropriate change of variables and propose a method to solve it. The simulation results show that in practical scenarios, employing the nonlinear energy harvesting model in the system design could reduce the transmitted energy, increase and the sum rate of the users. Manuscript profile
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  8 - Designing and explaining the professional development model of senior managers of Iran's telecommunications industry Case study: companies MCI, Irancell, Rightel
  Saeed Hadavand Afsaneh Zamanimoghadam Ali Taghipoorzahir
  10.52547/istd.31250.8.28.194
  The aim of this study was to design and explain the model of promoting the professional development of senior managers in the Iranian telecommunications industry. For this purpose, the exploratory mixed research method was used. In the qualitative section, in order t More

  The aim of this study was to design and explain the model of promoting the professional development of senior managers in the Iranian telecommunications industry. For this purpose, the exploratory mixed research method was used. In the qualitative section, in order to be aware of the main components of the research, semi-structured interviews with 17 senior managers of the telecommunications industry and faculty members of the university who potentially had more information about the professional development of managers. By analyzing the information through systematic coding method, the findings were identified as 5 main components including "individual maturity, organizational maturity, educational maturity, research maturity and professional maturity" and 25 sub-factors. In the quantitative part of the research and based on qualitative findings, a researcher-made questionnaire was designed and administered on a sample of 172 senior managers who were selected using the non-probability sampling method. The validity of the questionnaire was confirmed by four experts and its reliability was calculated by Chronbach’s alpha with a coefficient of / 876. Indicates the coherence of the questions and the significant lack of dispersion between them. Data were analyzed by confirmatory factor analysis using AMOS software. The results confirmed the dimensions of the extracted model. Finally, the current situation of professional development of senior managers in each of the dimensions of the model was studied, which according to the results, it was found that there is a significant difference between all calculated means and the hypothetical average. Calculating the difference between the means also showed that research maturity and professional maturity have a negative difference and senior managers of Iran's telecommunications industry have a significantly lower-than average level of growth that should be in the program. Educational considerations to be considered. Manuscript profile
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  9 - Structural model of individual development of managers of Iran Telecommunication Company
  Hassan Saddoghi Mahmood Abolghasemi Seyfollah Fazlollahi ghomshi
  10.52547/istd.31367.8.29.175
  This research is prepared to present a structural model for personal development in TCI. Personal development is an effective procedure in developing and empowering managers in a systematic way. Methods: The descriptive research method is correlational in which the co More

  This research is prepared to present a structural model for personal development in TCI. Personal development is an effective procedure in developing and empowering managers in a systematic way. Methods: The descriptive research method is correlational in which the correlations between the components are examined. The research community consists of 220 TCI managers selected using random sampling and another 140 selected from Morgan Table. We collected the relevant data using a personal development questionnaire for managers with reliability of 0.96. Of the components, 16 in three dimensions of development is reviewed including “the effective factors in personal development” and “actions performed in personal development” and “managers’ individual competencies”. Conclusion: Results extracted from LISREL and “structural equations modeling analysis” demonstrated that structural model for development of managers consists of “three dimensions in personal development”, “the processes and actions in personal development” and “the managers’ individual competencies” in TCI. Each dimension has its set of components and the model has suitable fitness. Consequently, managers’ personal development was examined with a systematic structure. Additionally, the effective individual factors have an influence on process and actions with a path coefficient of 0.37. Process and actions have an influence on individual competencies with a path coefficient of 0.17. The relationship between the components is indicative of a clear process and a correlation so that factors effective in the process and actions will have an influence on individual competencies. The validity of model will be approved using structural equations and quantitative relationships between dimensions of model. Manuscript profile
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  10 - Energy procurement of a cellular base station in independent microgrids with electric vehicles and renewable energy sources: Mixed-integer nonlinear programming model
  Reza Bahri saeed zeynali
  The cellular base stations are communication devices that ensure the connection in the world. Nevertheless, they are usually installed in remote places. This paper, studied the energy procurement of a cellular base stations in an independent microgrid with a hydrogen-ba More

  The cellular base stations are communication devices that ensure the connection in the world. Nevertheless, they are usually installed in remote places. This paper, studied the energy procurement of a cellular base stations in an independent microgrid with a hydrogen-based energy storage system, photovoltaic (PV) system, electric vehicles and a diesel generator. A new mixed-integer nonlinear programming model was used to deal with nonlinearities of the system components. The paper studied different uncertainties, such as the connection rate in cellular base stations, the driver of the electric vehicle, and PV generation, using stochastic programming method. The potency of the proposed method was studied in different case studies. The results prove that smart electric vehicle chargers reduce the risks and also cost/emission objective functions. The usage of this model can reduce the emissions as much as 18.60%. Manuscript profile
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  11 - The effect of strategic planning on the effectiveness of the organization in the telecommunications company of Kohgiluyeh and Boyer Ahmad province
  milad badam firoz
  In the current situation, strategic planning plays a key role in the success of organizations in the field of competition, and if it is formulated correctly, it leads to the selection of correct strategies, and if it is implemented correctly and on time, it leads to the More

  In the current situation, strategic planning plays a key role in the success of organizations in the field of competition, and if it is formulated correctly, it leads to the selection of correct strategies, and if it is implemented correctly and on time, it leads to the excellence of the organization. on organizational effectiveness in the telecommunications company of Kohgiluyeh and Boyer Ahmad province. In this research, Bryson's strategic planning model, which is a public and non-profit model, is used. Bryson is the first person to pay attention to the planning systems of government organizations. This model includes the dimensions of initial agreement, determining organizational tasks, stakeholder analysis, mission, understanding the organizational environment, determining issues, strategic determination. The strategy describes the plans and actions of the organization's perspective and the one-year operational plan. This research has investigated each of the dimensions of strategic planning on organizational effectiveness based on the Talcott Parsons model that worked within the framework of the principles of the natural system. The Parsons model includes four components of adapting to the goal, Coherence, continuity and preservation of the model are the tools used in this research, including two questionnaires of strategic planning and organizational effectiveness. Descriptive statistics and inferential statistics (regression) were used for analysis and the obtained results indicate that strategic planning and each of its dimensions have an effect on organizational effectiveness. Manuscript profile