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The primary synchronization signal (PSS) and secondary synchronization signal (SSS) transmitted in the 5G are used to perform a synchronization procedure. This paper proposes an effective residual frequency offset (RFO) estimation method in a 5G new radio (NR) system. The proposed RFO estimation method applies two branches correlation using PSS and SSS sequence. This paper shows via the simulation results that the inherent property of the PSS and SSS signals is exploited for a robust RFO estimation at various delay spread of wireless environments. It is demonstrated that the proposed RFO estimation scheme is efficient for the 5G NR system.

In this study, we designed a wideband (Ku-band) voltage-controlled oscillator based on a NMOS cross-coupled topology using the 65 nm complementary metal oxide semiconductor process technology, and simulated its frequency control range and phase noise to evaluate its performance. By adding current sources into the voltage-controlled oscillator, we improved the phase noise characteristics caused by power supply noise.

This paper introduces a 5G network simulator capable of conducting a performance test and analysis on new technological methods, industry requirements, and products. This is necessary for the creation of a 5G K-Test bench for developing new network architectures and service provision methods that are required for 5G mobile communication to achieve industry convergence. Based on ongoing 5G technical documents, the network simulator developed earlier determines the key technologies and requirements that should be further defined and designs the structure. In addition, by defining the I/O required for each interlocking function module and designing the interface between modules, the interlocking function module studies the reliable network simulator interlocking function, including the functions given in the standard.

Various technologies and standards for the Internet of Things (IoT) have defined the way devices should interact with each other to provide an intelligent IoT service to users in an efficient manner. Although the usability of system interface between the platform and users is one of the key factors for the success of IoT ecosystems, the manner in which IoT platforms should interact with users has not been well studied. Current IoT platforms provide a simple list-based interface to manage devices, which result in the degradation of their usability as the number of devices increases. In this paper, we propose an interactive web-based IoT management system where deep object detection techniques are adopted to facilitate user&rsquo, s device selection and management. The proposed system automatically recognizes the device type from video streams and accordingly generates smart controllers. The users can choose a device by touching an object in the video stream and use a smart controller to control the selected device. Finally, we show the feasibility of the proposed system through the implementation of a prototype which demonstrates a set of user scenarios.

The present paper analyzes the establishment of an overall network, necessary bandwidth, estimated performance and capacity, and the requirements of unit network factors and thereafter proposes the direction for testing/verification of products, for the purpose of developing a new network structure and a new method of service provision to support 5G mobile communications that pursues convergence between different industries.

When entering a PIN on the touch screen of smartphone, users have their unique patterns, which shows different time interval, strength, position, and usage angel. Using this user's pattern, it is possible to distinguish the imposter who knows the user's PIN, then the PIN verification can be enhanced in the smartphone environment. In this paper, we tested classifiers with five features that can be extracted from smartphone sensors. Also, we collected keystroke data for each user's posture, and compared the characteristics of the posture. We consider the importance of preprocessing and feature combinations.

Data security has a critical role in the larger context of information and system security. In this paper, we propose the anomaly detection system for securing database. Our approach is based on analyzing the user's access pattern stored in database log and detecting the anomalous access event. We consider three methods for this, user pattern analysis, machine learning analysis, and rule-based access control. Our experimental evaluation on both real and virtual database shows that our approaches work well.

This paper comparatively analyzes the performance of X-MAC and PW-MAC as asynchronous sensor MACs with tree-topology using virtual simulation. PW-MAC has better performance in comparison to X-MAC, but it is receiver-initiated and shows collision when data is sent to common receiver. Therefore, this study evaluates whether PW-MAC maintains better performance in tree topology having common receiver for all transmissions. The result of simulation on NS-2 showed better performance of PW-MAC than X-MAC in tree-topology.

Today, the power utilities are setting on the slow load growth and the aging of power equipment, and then could spend the efforts on the stability of system performance. Under structure of vertically integrated power industry, great cost has been spent to enhancing reliability of such power utilities. This paper presents the principle calculation of determining economic life cycle on the power transformer from economic aspect of asset management. Economic life cycle is calculated by life cycle cost analysis performed in accordance to IEC 60300-3-3. The proposed method will be expected to play an important role in investment decision making considering economic evaluation.

Recently, sensorless controls, which eliminate position and speed sensors in a permanent magnet synchronous motor drive, have been much studied. Most sensorless control algorithms are based on the back-EMF and speed estimations which are obtained from the voltage equations. Therefore, the sensorless control performance is largely affected by the parameter errors of a motor. This paper investigates an improved state observer with the parameter error compensation for the speed sensorless control of a permanent magnet synchronous motor. The proposed parameter estimation is obtained through the LMS algorithm minimizing the performance function of d- and q- axis current errors. The performance of the proposed algorithm is verified through the simulation and experimentation.

Recently, the size of wind turbines is increased. As a result, the permanent magnet synchronous generator (PMSG) plays an important role because of its simple structure and high efficiency. This paper proposes a torque and pitch control scheme for variable speed wind turbines. A torque controller is designed to maximize the output power below the rated wind speed and a pitch controller is designed to regulate above the rated wind speed. The controllers exploit sliding mode control scheme considering the rapid variation of wind speed. Since the aerodynamic torque and rotor acceleration are difficult to measure in practice, an observer is designed which estimate them. In order to verify the proposed control strategy, we provide stability analysis and present simulation results.

As an emerging technology, wireless mesh networks are making significant progress in the area of wireless networks in recent years. However, the nature of sharing transmission medium makes it challenging to fully exploit these networks. In an attempt to improve the radio resource utilization, several routing metrics have been specifically designed for wireless mesh networks. However none of these routing metrics efficiently tackles interference issues. In this paper, we propose a routing metric for wireless mesh networks, which takes account of the amount of interference by considering the traffic situation of adjacent nodes and selects less interfered path for transmission. The aim of this metric is to route the traffic through interference areas and balance the load amongst the network nodes. Simulation results show that the proposed routing metric reduces the end-to-end delay when compared to the MIC, ETT and hop-count routing metrics.

This paper presents the experimental results of hand-written digit recognition. This neural approach is based on the graph matching, a form of elastic matching, and one-variable stochastic simulated annealing (OVSSA) which is a mean-field annealing algorithm to find a global minimum of a real valued function. Experimental results show that this method is insensitive to displacement, scale changes and rotation, and promising to hand-written character recognition.