نشریه نوآوری های فناوری اطلاعات و ارتباطات کاربردی
پیاپی 1 (بهار 1400)

The Internet of Things (IoT) is intended to transform human life and unleash enormous economic benefits. However, inadequate data security and trust of the current IoT are seriously limiting its adoption. Blockchain, a distributed and tamper-resistant ledger, maintains consistent records of data at different locations, and has the potential to address the data security concern in IoT networks. While providing data security to the IoT, Blockchain also encounters a number of critical challenges inherent in the IoT, such as the huge number of IoT devices, the non-homogeneous network structure, the limited computing power, the low communication bandwidth, and error-prone radio links. This paper performs a comprehensive survey on the existing Blockchain technologies with an emphasis on the IoT applications, and identifies the Blockchain technologies which can potentially address the IoT’s critical challenges and hence suit the IoT applications. The above results along with the investigations on the potential adaptations and present enhancements in the Blockchain consensus protocols and data structures are fully elaborated.

Broadband wireless systems are subject to variable channel conditions due to destructive propagation features such as multi-path fading. The OFDM is a multi-carrier technique which can overcome these effects. This paper focuses on the evaluation of the SC-FDE algorithm, which is considered a suitable replacement for OFDM systems. The SC-FDE algorithm is a new technique in the field of wireless communications. This technique has been able to improve the time and frequency synchronization performance in addition to maintaining the channel estimation and compensation features of the OFDM technique. The SCFDE technique compensates the negative  features of OFDM systems, especially the RF amplifier sensitivity, the carrier frequency offset, and the PAPR challenge. In fact, SC-FDE systems are less susceptible to RF disturbances and power amplifier nonlinearity due to structural reasons, which improves the PAPR parameter in high-order modulation. In this paper, a new approach is used to apply the FZC sequence in synchronization and the channel estimation in the information frame. The performance of the radio link in 256 QAM modulation has also been investigated. Furthermore, training sequence transmission in data frames has been reduced by selecting an adaptive scheme for framing. This scheme can reduce the transmission of the training sequence up to 4 times.

It has been demonstrated in the electronics industry, that miniaturizing the silicon components below 10 nm and integrating million of them in a chip would not be a good idea. This is due to the high-energy consumption, high-cost fabrication, the limitations originating  from quantum mechanics, and technological difficulties that obstacle the further miniaturization of electronic devices. Therefore, researchers should think about something out-of-the silicon-box to fabricate a more compacted electronic device. Accordingly, through evaluating and discovering the wide range of molecular structures which enable effective data encoding and manipulation, molecular informatics can be an appropriate alternative to the conventional digital logic. In this regard, molecular platforms can be considered as computing devices, which convert the physical/chemical inputs into the desired outputs by employing a set of logic operations. This field is related to the hardware subcategory of quantum computing technologies, and therefore, the fabrication of more efficient molecular electronic devices and sensors can produce positive meaningful effects on the defense and security abilities of a country. In this review paper, a brief history of molecular devices is initially presented because awareness of the evolution of a scientific subject can underpin more fundamental progress. In the next step, the main reasons for changing the paradigm toward molecular devices are explained, and by introducing the logic gates used, the fundamental and technological limitations of conventional devices are reviewed. Then, the different functionalities of molecular logic gates in the two aspects of molecular electronics and chemical logic sensors are discussed in a detailed way to demonstrate the capabilities of molecules in different computational systems.

Quantum cryptography or quantum key distribution (QKD) is a technique that allows a bit stream to be used as a key in cryptographic protocols by protecting its distribution. Extensive studies began when it was observed that quantum computers can break public key cryptography based on the number theory. The use of quantum cryptography provides complete security and confidentiality and has proven invincible against major attacks for decryption. Although the security of quantum cryptographic protocols has been mathematically proven, it should be emphasized that its implementation in the real world suffers from the limitations of physical devices, which in turn can make it vulnerable to misuse by eavesdroppers. The result of these studies has been the introduction of the first quantum key distribution protocol called the BB84 protocol. The purpose of this article is to study some if its applications, and then explain and review the protocol structure, implementation, and security analysis.

Today, WDM wavelength division multiplexing systems have made fiber optic communications more efficient. A WDM multiplexer combines the signals received from several separate transmitters in order to send them with minimal loss and scatter in a single-mode fiber. The transmitted signals are separated from each other at the receiver. The use of EDFA-doped fiber amplifiers in WDM-based optical networks will increase data transmission rates and communication distances. In this research we assume a fiber optic communication link with a four-channel WDM system, and use the Optisystem software to simulate the desired links. The main goal is to maximize the communication distance between the transmitter and the optical receiver and the data transmission rate. The hypothetical values of the QF quality factor and the BER bit error rate guarantee the quality of the communications. The important results are obtained from the simulations in this paper, can be effectively used in analyzing the performance and design of WDM systems with different data rates and communication distances.In this paper, important results are obtained after the simulations. The use of these results is very effective in analyzing the performance and design of WDM systems with different data rates and communication distances.

One of the approaches that has recently entered the field of management and can best motivate and guide innovation in the field of human resource management is the Internet of Things. The basis of this concept is the assumption that all objects can communicate with each other via the Internet. Therefore, the purpose of this study is to identify the components of human resources in the Internet of Things, based on previous researches in this field and to extract the relevant components based on the meta-combination method. Hypertext is not an extract from the interpretations of similar studies; rather, it is the integration of the interpretation of the main findings of the selected studies to create comprehensive and interpretive findings that indicate the researcher's deep understanding in this regard. Using these 5 keywords: “IoT”, “human resources”, “IoT and human resources”, “human resource management”, and “human resource information system” to explore and exploit the Emerald, ProQuest, SID, and Web of Science databases, as well as Google, the researchers have reviewed scholar and student dissertations defended in recent years. In the evaluation process, the researchers selected 20 articles out of 921 articles and dissertations for data analysis. Findings of this study showed that components such as databases (data collection and transmission), human relations in the organization, human resource monitoring, human resource components and processes, human resource information system (HRIS), pre-deployment requirements, and post-deployment requirements must be intelligently monitored by human resource managers. Also, the relationship with human resource systems and processes needs to be considered more than other dimensions, and then it is important to address the dimensions of challenges and features resulting from the effects of the establishment of the Internet of Things on human resources. The more human resource managers can explore the basic themes presented in this research, the more easy and less challenging, the IoT-based human resource system would be installed, deployed, and evaluated.