فهرست مقالات Wireless sensor networks

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  1 - An efficient solution for management of pre-distribution in wireless sensor networks
  Asghar Dolatabadi Hamid Haj Seyyed javadi
  A sensor node is composed of different parts including processing units, sensor, transmitter, receiver, and security unit. There are many nodes in a sensor unit. These networks can be used for military, industrial, medicine, environmental, house, and many other applicat چکیده کامل

  A sensor node is composed of different parts including processing units, sensor, transmitter, receiver, and security unit. There are many nodes in a sensor unit. These networks can be used for military, industrial, medicine, environmental, house, and many other applications. These nodes may be established in the lands of enemies to monitor the relations. Hence, it is important to consider conservation of communications, declaration, and key removal. The locations of nodes are not usually defined in the networks. When a secure connection is required they can be used by symmetrical or asymmetrical encodings. A node can just make secure connection, if they are in same radio range or have a common key. In dynamic wireless sensor networks compared with static networks the sensors are moveable and can be added or removed. This research makes an attempt to investigate the challenges of key management for encoding. It also tries to solve other remained problems in this field. Therefore, distribution and key management schemes supplying security and operational requirements of sensor networks are examined in fuzzy clustering and suitable protocol for key management. پرونده مقاله
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  2 - Improvement of Energy, Lifetime and Delays in Underwater Wireless Sensor Networks by Effective Deployment of Relay Nodes
  Reyhane Zehtabzadeh Reza Gholamrezayi
  ABSTRACT: According to the importance of underwater exploration, the attention of many researchers has been attracted to underwater sensor networks (UWSNs). Problems of UWSNs are large propagation delay, low bandwidth, and limited energy. Because of these reasons, in t چکیده کامل

  ABSTRACT: According to the importance of underwater exploration, the attention of many researchers has been attracted to underwater sensor networks (UWSNs). Problems of UWSNs are large propagation delay, low bandwidth, and limited energy. Because of these reasons, in this paper, we propose a new routing method in UWSNs that considers these factors and also achieves better load balancing in the network. In this method, relay nodes are used for routing. The relay nodes have a higher traffic load compared to the other nodes. They remove some burden from the overloaded nodes. The relay nodes shorten the transmission distance between source and destination. They have more energy compared to the other nodes. Our results show that the deployment of relay nodes in sensor networks helps to balance energy consumption and enhance the network lifetime. Nodes, after calculating the distance to the relay nodes and finding the nearest relay node, transmit packets to the nearest relay node for onetime immediately, so this method does not have holding time and it has less delay. The results are compared with DBR and CODBR. The results show that our method achieves more network lifetime, less delay and energy consumption compared to DBR and CODBR. پرونده مقاله
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  3 - بررسی قابلیت اطمینان با معماری جدید مدل مارکوف گره پشتیبان با نرخ تعمیر و تعویض بهتر و نظارت بیشتر در پرهیز از خرابی شبکه‌های حسگر بی‌سیم صنعتی
  احمدرضا زمانی محمد علی پور مینا رامین شقاقی کندوان
  گره‌های حسگر به¬دلیل کاربردهای متنوع محیط‌های عملیاتی، مستعد خرابی هستند. ایده این مقاله، ارایه یک¬معماری جدید با مدل مارکوف برای بهبود قابلیت اطمینان می¬باشد. در اصلاح ایده¬هاي قبل با توجه به خستگي¬كاري، هزينه مصرف انرژي و تعميرات بالا مي¬توان از ایده افزایش نرخ تعمیر چکیده کامل

  گره‌های حسگر به¬دلیل کاربردهای متنوع محیط‌های عملیاتی، مستعد خرابی هستند. ایده این مقاله، ارایه یک¬معماری جدید با مدل مارکوف برای بهبود قابلیت اطمینان می¬باشد. در اصلاح ایده¬هاي قبل با توجه به خستگي¬كاري، هزينه مصرف انرژي و تعميرات بالا مي¬توان از ایده افزایش نرخ تعمیر و تعویض در پرهیز از خرابی با در¬دسترس¬بودن گره¬های جایگزین با برنامه¬ريزي دقیق تعمیرات ، بهره برد. مزاياي این¬روش کاهش میزان خرابی ، افزایش قابلیت اطمینان، پیاده سازی و استقرار سریع، بهره¬وری انرژی و صرفه¬جویی اقتصادی، بهبود عملکرد و عمر مفید شبکه، کاهش تاخير و جوان¬سازی و پویایی سیستم می¬با¬شد. ساختار روش پیشنهادی با استفاده از حالت خواب و بیداری گره آماده به¬کار سرد یا گرم به¬گونه¬ای است که گره یدکی به موازات گره اصلی قرار می¬گیرد و در صورت آسیب-دیدن یک یا دو گره، سیستم برگشت¬پذیر می¬باشد و می¬توان خرابی را تعمیر یا جایگزین نمود. تکنیک‌ زمان بیکاری و در¬دسترس¬بودن حسگر یدک پشتیبان ، نقش مهمی در کاهش مصرف انرژی دارد. و کارشناسان واحد پشتیباني تنظیمات پیکربندی را به گونه‌ای انجام می¬دهند تا در زمان بیکاری، تجهیزات به حالت خاموشی یا آماده¬به¬کار بروند و در صورت آسیب¬دیدن یک یا دو گره، ابتدا گره یدکی سالم بیدار و در سرویس و سپس گره آسیب¬دیده تعمیر و تعویض ¬و در حالت آماده¬به¬کار یا خواب قرار گیرد. از نتایج حاصل از نوآوري این روش، تأکید بر نظارت سلامتی گره، جلوگیری از خرابی و بهبود نرخ تعمیر و تعویض، کاهش مصرف و بهره¬وری انرژی می‌توان اشاره نمود. نتایج شبیه‌سازی در مقایسه با مدلهای قبل، بهبود بهتری را نشان می¬دهد. پرونده مقاله
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  4 - Localization of Underwater Wireless Sensor Network Nodes Using Cuckoo Optimization Algorithm
  Leila Falahatpisheh
  Underwater Wireless Sensor Networks (UWSNs) are considered as wireless sensor networks whose main task is to sense underwater events and send information to the sink. This information becomes valuable when the exact location of the occurrence is known. Generally, underw چکیده کامل

  Underwater Wireless Sensor Networks (UWSNs) are considered as wireless sensor networks whose main task is to sense underwater events and send information to the sink. This information becomes valuable when the exact location of the occurrence is known. Generally, underwater sensor nodes are not equipped with devices such as the Global Position System (GPS) with the purpose of reducing network costs. Therefore, finding the location of the nodes should be done using another exact method. In this paper, we intend to find the location of the underwater sensor nodes by introducing a new method based on the Cuckoo Optimization Algorithm (COA).We will compare the proposed method with the related methods in terms of the localization error rate and the number of nodes discovered. The results of the comparisons show that the proposed method can greatly reduce the error rate of the localization of the sensor nodes. پرونده مقاله
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  5 - MAC Protocols in Underwater Wireless Sensor Networks: Issues and Simulations
  Reza Mohammadi Seyyed Yahya Nabavi Reza Javidan
  Underwater Acoustic Wireless Sensor Network (UAWSN) use acoustic signals to transmit data. Acoustic signals in underwater environment have high bit error rate, long propagation delay and limited bandwidth. Another constraint in UWASN is energy. Due to these constraints, چکیده کامل

  Underwater Acoustic Wireless Sensor Network (UAWSN) use acoustic signals to transmit data. Acoustic signals in underwater environment have high bit error rate, long propagation delay and limited bandwidth. Another constraint in UWASN is energy. Due to these constraints, design of energy and bandwidth efficient and propagation delay aware MAC protocol is a great challenge in UWASN. Underwater sensor nodes have to share medium. The main role of the MAC layer protocol is to decide when a node accesses a shared medium and to resolve any conflicts between nodes. In this paper, we evaluate the performance of three famous underwater MAC protocols UWAN-MAC[1], R-MAC[2] and Slotted FAMA[3] in terms of packet drop rate, throughput and energy consumption. We have used Aquasim simulator to evaluate MAC protocols. پرونده مقاله
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  6 - Optimization of Mobile Base Station Placement to Reduce Energy Consumption in Multi-hop Wireless Sensor Network
  Gholamreza Farahani Ameneh Farahani
  Nowadays, wireless sensor networks (WSNs) are widely used in different sectors. The problem in these networks is the non-rechargeable batteries of these sensors, which limit the lifetime of the network. Therefore, the optimal energy consumption of sensors is an open res چکیده کامل

  Nowadays, wireless sensor networks (WSNs) are widely used in different sectors. The problem in these networks is the non-rechargeable batteries of these sensors, which limit the lifetime of the network. Therefore, the optimal energy consumption of sensors is an open research topic. In this paper, a new algorithm with the Development of Genetic Algorithm with the Floyd Warshall (DGAFW) has been proposed. Using the proposed DGAFW algorithm, the number of clusters and nodes assigned to each cluster is first determined with the Floyd Warshall algorithm and then the Cluster Head (CH) is selected using fuzzy logic. Finally, the optimal placement of the base station is specified by the combination of the Genetic Algorithm and the Floyd Warshall. The DGAFW algorithm is based on minimizing the distance of sending multi-hop messages. The simulation is carried out in MATLAB 2023a online software. The simulation results obtained from the DGAFW algorithm have been compared based on the distance, the amount of remaining energy in each round, and the number of rounds of network activity in the case where the location of the base station is fixed or randomly determined in each round. The results obtained show that the DGAFW algorithm compared to the case of random base station and fixed station respectively, has 12.7% and 14.3% shorter average message-sending distance in each round, 14.7% and 19.1% more residual energy and also 36% and 48% more rounds of network activity. پرونده مقاله