نشریه دستاوردهای نوین در برق،کامپیوتر و فناوری
پیاپی 3 (تابستان 1401)

Today, technology is advancing day by day. That the world of communications embraces a huge part of technology. The Internet, social networks, and telephone calls are part of the world of communication. The most important part of these cases is the mobile device. This development also has many security aspects. In this article, we are going to examine the mobile IMEI code. And let's examine the mobile registry plan in Iran in terms of security aspects, what are its advantages and disadvantages. It also examines the use of a decentralized identity management framework to implement a system to combat counterfeit smartphones, which provides features of identity creation and transfer of ownership along with fast and secure capabilities. On the other hand, reports of stolen equipment and insecure people in the communication platform will be followed up in the shortest time.

In this paper, a wearable dual-band filter is designed and simulated to operate on ISM frequency bands. For this reason, in addition to recognizing the mentioned frequency bands, the design process of wearable filters has also been studied. In this regard, first, the desired characteristics of a filter are examined. These characteristics include scattering parameters (S-Parameters) and group delay. In the following and in explaining the objectives, by defining numerical values for these characteristics, the framework of the paper is determined. Since the subject of this article is the design of wearable filters, a substrate that has this capability should be used. In this regard, a flexible substrate with felt, thickness 1.4 mm, dielectric constant of 1.45, and tan (δ) = 0.001 has been used. Using this dielectric, a proposed dual-band filter with dimensions of 29.4×33.4 mm2 was designed. The frequency bands covered include 2.4-2.5 GHz and 5.15-5.35 GHz. These bands are standard values covered by ISM. At all operating frequencies, the conditions S11 < -10 dB and S21 > + 0.5 dB are met.

Veneer laminate is a conservative treatment for unsightly anterior teeth; The continuous development of dental ceramics offers doctors many options for creating beautiful and practical porcelain veneers; This evolution of materials, ceramics and adhesive systems improves the beauty of the patient's smile and self-esteem; Physicians need to know the latest ceramic materials in order to be able to recommend them for use based on their applications and techniques, and to ensure clinical success; In this study, the most important parameters determining long-term success, proper use and clinical limitations of porcelain veneers have been investigated.

In this paper, we study the microgrid network including solar energy, battery and supercapacitor using fuzzy controller. Due to the voltage changes in the DC bus, it is necessary to adjust the solar cell and the battery using the control method and converter. Also, with the help of batteries and supercapacitors, this equipment is used when there is a need for more power in the load. Supercapacitors are used for instantaneous times and batteries for longer periods of time to power output loads. A fuzzy control system is a control system based on the fuzzy-mathematical logic of a system that analyzes analog input values in terms of the logical variables they contain and is used in several parts of the system to improve performance. The simulation is performed in MATLAB / Simulink software and the output results confirm the accuracy and validity of the system used.

Rapid advances in the Internet and communications have greatly increased the size of the network and networks related data. As a result, many new attacks are emerging, challenging network security to accurately identify intrusions. In addition, the presence of hackers with the aim of carrying out various attacks within the network cannot be ignored. Intrusion detection systems are an important protection tool for the network. Intrusion detection systems are classifiers that receive input records and predict the class of types of attacks. In network attacks, there are various deep learning algorithms that have been proposed for intrusion detection systems. Over the past decades, researchers have used a variety of deep learning algorithms to classify and detect malicious traffic from normal traffic without prior knowledge of attack pattern. This article provides an overview of deep learning algorithms that use for intrusion detection systems. A separate section is dedicated to presenting the datasets used in intrusion detection systems in particular, the two main datasets, KDDCup99 and NSL-KDD. Evaluation criteria and implementation tools in intrusion detection systems are also examined.

A Voltage Reference is a pivotal block in several radio-frequency and mixedsignal applications, for instance, data converters, PLLs and power converters. The most used CMOS implementation for voltage references is the Bandgap circuit due to its high predictatibility, and low dependency of the supply voltage and temperature of operation. This thesis studies the Bandgap voltage references. The relevant topologies usually employed to implement Bandgap voltage references are investigated, and the limitations of these architectures are discussed.In this thesis First-order curvature correction Bandgap voltage references and Second-order correction curvature Bandgap voltage references in low voltage and low power are investigated. To support our work, Bandgap voltage references are designed using the standard TSMC 0.18 μm CMOS Technology and simulation results are compared with previous works.

One of the most important issues in the space field of countries is the tracking of low earth orbit (LEO) satellites with high accuracy. Due to the fact that conventional filters are not able to track systems with nonlinear dynamics and their tracking is associated with many errors, the use of nonlinear filters is recommended. To solve nonlinear and noisy filtering problems, the Kalman filter algorithm is one of the most suitable methods. This filter is based on the principle of linearization of measurements and model development using Taylor series expansion. The Kalman filter can change the state variables of the system in non-linear stochastic systems where there is disturbance in the process and noise in sensor measurements. Estimate the optimal form. In this article, the satellite motion equations are applied separately to the developed nonlinear filters (EKF) and the sampler Kalman filter (UKF), and finally, by examining the performance of these two filters, it is observed that the sampler Kalman filter performs better compared to the Kalman filter. has developed The satellite studied in this article is NOAA19 meteorological satellite.

This paper discusses the Wavelength Division Multiplexing (WDM) application over the Plastic Optical Fiber (POF) used for data and networks communications of selected equipments onboard a navy ship. Four different wavelengths are used to connect equipments throughout the ship for access by the user, namely; LAN connections, telephone line, CCTV video image and central video/audio entertainments network. Some network topologies possible to be used are explained and improvised mesh topology is studied as possible architecture to be used for this study. The equipments will be able to be controlled and monitored from three different control centers; the Bridge, the Machinery Control Room (MCR) and the Combat Information Centre (CIC) for safety and security connection with redundancy feature, good performance and resilience connectivity. Some parameter such as output power and power losses in the networks were observed. The system promises an enhanced data transfer with the benefits of less overall ship’s weight and therefore will improve the speed and consume less fuel for new and future ship design or ship embarking life extension program.

Although the lack of data is one of the important challenges for research in the field of natural language processing, but this challenge is more acute in the Persian language, so finding a high-quality and comprehensive dataset in the Persian language is a difficult task. In addition to that, having some problems such as the ability to categorize and not complying with the storage standard are among the problems of the existing datasets, each of which can affect the learning rate of the model, the results, and the error rate in the experiments. For this reason, all these reasons made us seek to collect and prepare a dataset that covers all such problems and reduces the amount of error when using data in different models. In this research, we have designed and used a crawler to collect textual data. By crawling on one of the news bases, it has been able to collect data sets in five columns: title, summary, text, tag, and publication date. The textual data has been normalized with the help of one of the Persian language libraries in the Python programming language and stored in csv and xml formats and made available to fellow researchers. The tags in this dataset include 13 main tags of sports, art and media, culture, science and progress, political, foreign policy, life, family, society, education and training, international, economic and provinces. Among the tasks that can be done on this data set are text classification, text extraction, text summarization and title recognition. Also, one of the prominent features of this data set is its comprehensiveness, the amount of suitable data, the existence of useful features, having unique features, as well as storage in a standard format. This dataset is a product of the Language Processing Department of Imam Hossein Comprehensive University and can be downloaded and used through the link mentioned in the footnote of the next page and with respect to copyright.

In recent years, the use of unmanned aerial vehicles (UAVs) in military and civilian missions has increased due to the ability to float, fly at low height and in closed spaces. In the category of UAVs, there is a category called quadrotor, which has received much attention researchers due to its special features. The main applications of this category are related to their vertical landing and take-off, maneuverability and high controllability. Unmodeled dynamics, uncertainty, disturbance, and the unknown parameters of the quadrotor system are some of the problems that complicate the design of the controller for it, and as a result, it has found a special place in engineering fields, especially aerospace and control engineering. In this paper, PID, LQR and linearization feedback controller with PD were applied to the quadrotor system, so as to guarantee the stability of the closed-loop system. The simulations in MATLAB software show that the LQR controller is superior to the other two controllers.

With the development of technology, the use of social networks has become more popular. One of the most popular social networks is the Twitter platform. Sentiment analysis of users' tweets plays an important role in showing users' feelings about the existing conditions of society. In recent years, due to the fact that the text of users' tweets have become more conversational, sentiment analysis has become problematic and reduced its accuracy; It also makes natural language processing difficult. In this research, a method for sentiment analysis of Persian tweets based on the combination of semantic relations and support vector machine classification has been presented. FastText semantic relation is used to extract features. Considering that a large number of features have been extracted; They should be reduced, which is done by using long-short-term memory (LSTM) neural network. In the last part of the proposed method for the classification of sentiments in tweets, the support vector machine model is used. The evaluation criteria used in this research were precision, accuracy, recall and F criterion, and the evaluation results were 83.9, 84.3, 83.9 and 84, respectively. The results of the experiments show the applicability of the proposed method in analyzing the emotions of Persian tweets into six classes of anger, sad, joy, disgust, surprise and fear.