نشریه فناوری اطلاعات و ارتباطات انتظامی
پیاپی 8 (زمستان 1400)

Cloud computing and online storage of information is realized as an excellent replacement for hardware memory mostly because it is the transfer and use of information by cloud computing are less expensive, more practical, simpler, faster, and more accessible. However, some issues should be taken care of. One of these issues is cyber threats which are much greater than what we had in the past. The current technologies and even the most advanced computers and classical cryptography are not able to deal with cyber threats in this volume of information transfer and use. On the other hand, there is quantum computing which is the most advanced type of data transmission we know. It relies on the existence and presentation of quantum computers and will be the only way to smarten and provide cyber security in the future. Quantum computing focuses on building very fast computers using the concepts of quantum physics, and cloud computing allow this computing power to be provided as a service. Cloud-based quantum computing provides direct access to quantum simulators and processors, and this could revolutionize intelligence. With the advent of quantum computers, the security of today's cryptographic systems is compromised, since many of today's cryptocurrencies are based on the difficulty of calculating the prime factors of numbers, and the Shor’s quantum algorithm can break these cryptographies. Grover's quantum algorithm can also make it easier for us to access passwords. In this article, we first briefly discuss the basics and concepts related to quantum cloud computing.

In this paper, an artificial intelligence model for energy-aware task scheduling is based on learning automata in Fog Computing applications. fog computing is a distributed computing layer that acts as an intermediate layer between the cloud and the Internet of Things to improve the quality of services. One of the most important factors in energy consumption is related to task scheduling. This paper examines the timing of tasks in a fog environment to reduce energy consumption, makespan, and cost using learning automata. Then, for the first time, a neural network is introduced as a model of artificial intelligence based on learning automata in fog. The proposed neural network model has the ability to predict the relationship between the parameters of completion time, energy, and cost based on the number of virtual machines. The results of the proposed artificial intelligence model show that all the mentioned parameters are predicted with less than one percent accuracy.

VOIP technology provides significant benefits for customers and communication service providers such as cost savings, good media services, telephone and service portability, mobility and integration with other applications. However, there are many challenges in working with VOIP technology; Such as architectural complexity, interoperability issues, service quality issues, and security challenges. Among these issues, security risks are the most important. This study provide an algorithm to improve the security of encrypted conversations based on VOIP. In this our simulation, we use the NS2 emulator with the version 2.35NS that it is under Linux. The proposed method is AES-GCM encryption, which is compared with AES-CTR in different network parameters with two factors of time and packet size. The obtained results show that the package delivery rate in AES-GCM is higher than the operating mode of AES-CTR, which is the reason for the superiority of AES-GCM in providing service quality, furthermore in this method, encryption time, decryption, power consumption, and packet loss rate in encryption are far less than operational. In another comparison, the required time to sending the package and the delay rate in transfer of package in the proposed mode of operation is far less. Therefore, in the proposed method the low rate of time and delay are required in comparison with the AES-CTR method.

Due to the increasing use of Inertial Navigation Systems (INSs) in various fields, increasing the accuracy and efficiency of this system is significant. INS is a standalone system that works in any weather conditions and can provide continuous navigation information of position, velocity, and attitude without affecting the environment. However, due to errors in gyroscope and accelerometer sensors, the accuracy of INS sensor performance decreases over time. Therefore, the main problem in using INS for navigation systems is the unlimited errors that occur over time. In other words, over time, its performance suffers from errors that are increasing rapidly. Therefore, to achieve the desired outputs, noise removal must be performed. In this paper, according to the types of sensors, the best noise removal method has been presented. The wavelet noise removal based on the lifting scheme is utilized for de-noising. The lifting method is real-time and does not require blocking the received data. Also, we have leveraged some multi-level liftings. Further, we propose an optimization method based on the genetic algorithm to increase accuracy by combining the results of multi-level liftings. For evaluation, two types of dynamic and static data have been used. The achieved results have clarified the effectiveness of our proposed method. Therefore, a suitable method for good, reliable, and fast noise removal is presented.

Today, paying attention to risk management and removing its barriers is one of the effective indicators on productivity and competitiveness. The purpose of this study is to investigate the effect of organizational risk management on competitive advantage with the mediating role of information technology.The present study is a descriptive research using survey method and from the perspective of research objective, is an applied and non-experimental research. Statistical population of this study is Iran Khodro Company managers and experts that is estimated about 450 people and using simple random sampling method and according to Cochran's formula, the sample size is 212 people. The data were collected through questionnaires, and were analyzed using structural equation modeling method and Amos software and also Sobel test for examining the mediators.The highest impact factor was associated to the follow-up component equal to 0.49 and the lowest one was associated to the identification component equal to 0.28 on the competitive advantage with the mediating role of information technology in Iran Khodro Company. All research hypotheses in line with the impact of organizational risk management including the components of identification, analysis, planning, Follow-up and control on the competitive advantage with the mediating role of information technology in Iran Khodro Company were accepted.

In the information age, knowledge is the most important factor for success for an individual and an organization. On the other hand, unlike the old organizations, knowledge-based and intelligent technology-based organizations have advanced technology and manage and utilize knowledge and information in order to improve efficiency, better customer service and follow up on constant changes. The statistical population of this study included 587 managers, senior experts and operational users based in the technology-oriented intelligent organization. By multi-stage random sampling method, 230 people were selected as the sample size.The data collection tool was a researcher-made questionnaire, which includes 6 factors: organizational structure, organizational culture, information technology infrastructure, human resources, strategic aspect and leadership aspect of education and retraining. The face and content validity of the questionnaire were confirmed by experts.The reliability of the questionnaires was confirmed by calculating the Cronbach's alpha coefficient of 0.82. Data analysis was performed at two levels of descriptive and inferential statistics (t-test and factor analysis and Friedman test). The results showed that organizational culture with an average rank of 16.26 first rank, organizational structure with an average rank of 13 second rank, human resources with an average rank of 12.11 third rank, information technology infrastructure with an average rank of 63.11 fourth rank, education and retraining with an average rank of 10.98 rank Fifth and the strategic and leadership aspect with an average rank of 9.48 is in sixth place.

The purpose of this article is to design and manufacture the desired RFID antenna materials to positioning. Since the shape and size of the antenna limit its use, the design and manufacture of flexible materials with the ability to absorb and radiate properly, especially in the three-dimensional design of the desired antenna is the current article. In this regard, the use of silver nanoparticles in the design of the mentioned materials has been studied and the properties of the resulting material have been evaluated and presented based on laboratory results. The size and morphology of silver nanoparticles in conductive ink, based on electron microscopy and histogram curve, is about 7 nm and is spherical. Using an absorption spectrophotometer, the ultraviolet light absorption spectrum of the ink is obtained at a wavelength of 410 nm, which indicates the presence of silver nanoparticles. Also, the average measured electrical conductivity is 4.400×107 s/m.

This paper introduces a novel microstrip dual-band bandpass filter that combines a stepped impedance resonator (SIR), parallel stubs and asymmetric input and output ports on both sides. This configuration can lead to desired frequency characteristics like central frequency and required band passes. The required bandwidths will be optimized by stepped impedance resonator and the return and the insertion losses by the parallel stubs on both sides of the structure. Finally, we obtained a suitable isolated frequency response between the two passes bands by making asymmetric the location of the input/output port on the sides. For design and manufacturing a dual-band filter with 4.7 GHz and 7.16 GHz frequencies with the same 87 MHz bandwidth in each band, a suitable structure is proposed and used. The circuit analysis of the filter is performed section by section, to better examine results. The simulation and test results of the proposed structure indicate a 0.92 and 0.45dB insertion loss and 21 & 24.31 dB return losses in the two bands. In the following, we show by changing the dimensions of the middle stubs, the central frequency and bandwidth of the filter can be tuned. The main features of this filter are compact size, dual bands, and proper passing bands isolation.

In the coupler design, there are some important parameters, including size reduction, harmonic suppression and insertion loss, which affect the quality of the final product. Thus improving each of these parameters contributes to a more efficient design. In this paper a novel Rat-race coupler with size reduction and harmonics suppression is designed. In the proposed coupler structure, parallel capacitor and indicator are used. The proposed device correctly works at 800 MHz and occupied small size of 46.3mm×23.15mm (0.17λ ×0.08λ), which shows more than 63% size reduction compared to the conventional coupler. The proposed coupler not only reduce the circuit size but also suppresses 2nd, 3rd and 4th harmonics with 21dB, 38 dB and 20 dB attenuation levels, respectively. The proposed coupler provides wide rejection band from 1.6 GHz to 3.3 GHz with more than 20 dB attenuation level. The insertion loss parameter is less than 0.1 dB and more than 40 dB return loss and isolation are obtained at operating frequency, which show superior performance of the proposed Rat-race coupler.

In this paper, a class E/F5 amplifier is designed and analyzed at 1 MHz frequency. A new technique is presented in the proposed circuit, in which a load capacitor is placed in the output circuit of the amplifier. The proposed technique has improved the performances of the proposed circuit, such as higher maximum frequency and lower switch voltage. In the designed circuit, the IRF510 transistor is used as the switch and the circuit is simulated using PSpice software. The proposed circuit is analyzed considering ZVS (zero voltage switching) and ZDS (zero derivative switching) conditions, which the simulations result has confirmed the analyzed results. The results show efficiency of 92.8%, output power of 30W, and normalized voltage of 2.8 which shows good improvement, compared to the other amplifiers. The proposed amplifier with such superior results can be considered as a good candidate for the inverter applications in the military vehicles.