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With the development of IT technology in recent years, various digital technologies and automation technologies are also used in shipbuilding / shipping industry, and the existing closed structure is changing to an ICT-based open structure. If the various systems (navigation communication, engines, etc.) installed and operated on ships have been limited to each unit function and provided functions, these changes are now the ones to an integrative and comprehensive ship operating system which integrate data and share mutual information through interworking and integration between internal and external systems of the ship using the ICT technology based on the unit system. Moreover, the development of Hyper-connectivity and Super-intelligence technology of the 4th Industrial Revolution has a rapid and widespread influence on the shipbuilding and shipping industry. In this change, we have designed a smart autonomous ship architecture that enables Unmanned Ship by using Intelligence Information Technology (ICBMS + AI), which is the core technology of the fourth industrial revolution, and remote ship operation and management system that can operate it safely, economically and efficiently. In this paper, we derived the technology through the analysis from various angles such as components of ship, characteristics of shipping logistics, duties and roles of crew, and applications of intelligent information technology and proposed Smart Autonomous Ship and Shore Architecture in which the information between Smart Autonomous Ship and Data Center is converged and is organically integrated and operated by applying these technologies to Smart Autonomous Ship and Shore Data Center.

Over the last decade, the number of Low-Power Wireless Access (LPWA) devices has increased remarkably. It has become crucial to introduce several LPWA technologies to share the burden of catering to the demands of these devices. Narrowband Internet of Things (NB-IoT) is one such new cellular LPWA technology which has been standardized by 3rd Generation Partnership Project (3GPP) in June, 2016. It was developed with the aim to support low-complexity and low-power devices serving areas of poor radio coverage. In this survey, we review NB-IoT technology in detail. NB-IoT’s architecture is derived from that of Long Term Evolution (LTE) cellular technology, which is another 3GPP technology. We first discuss the architectural changes made to the design of LTE to derive the design of NB-IoT, including changes in physical layer and layer-2 architecture. Next, we describe the various features introduced for NB-IoT in 3GPP Rel-13 and follow it up to describe the enhancements made in subsequent 3GPP releases until 3GPP Rel-16. Then, we review, in depth, the research work done on various aspects of NB-IoT. We follow it up with a discussion on the combination of NB-IoT with other interesting cellular technologies like Device-to-Device communication (D2D), Non-Orthogonal Multiple Access (NOMA), social IoT, and 5th Generation New Radio (5G NR). We also look into a wide variety of real-world applications of NB-IoT. Finally, we point out a few open issues of NB-IoT and identify possible future research directions.

The paper discusses an adaptive multiuser receiver for CDMA systems in which the scaled unscented filter (SUF) and the square root unscented filter (SURF) are used for joint estimation and tracking of the code delays and multipath coefficients of the received CDMA signals. The proposed channel estimators are more near-far resistant than the conventional extended Kalman filter (EKF) and present lower complexity than the conventional particle filter (PF) based methods. To present meaningful performance measures, the modified Cramer-Rao lower bound (CRLB) and computational complexity metrics are derived for the proposed and existing channel estimators. Computer simulation results demonstrate the superior performance of the proposed channel estimators. The proposed estimators are also shown to exhibit lower complexity relative to the PF.

An alternative state estimator structure for linear time-invariant systems named for dynamic observer is presented, which can be considered as an extension of the usual observer in its configuration. As a possible design method for the dynamic observer, an efficient and plausible design algorithm is also provided. The mechanism of the proposed dynamic observer design is the dual of the output feedback controller design. The essential characteristics of the dynamic observer to be qualified as an effective observer are addressed.