Small unmanned aircraft such as drones are attracting considerable attention in various fields and for actual services. In general, a small unmanned aircraft transmits telemetry data such as position information and video data through a wireless communication link. On the other hand, a ground control station/controller transmits control commands. Therefore, wireless communication techniques are essential for the safe operation of unmanned aircraft systems. This paper outlines wireless communication techniques used for small unmanned aircraft systems.

Secure computation has been a major research topic in cryptography since the 1980s. It can accelerate the application of sensitive data since one can analyze data while ensuring their secrecy by using secure computation. Despite this advantage of secure computation, it has not been widely used in practice, one of the main reasons being its inefficiency. Secure computation tends to require heavy computation and communication compared with computation in the clear. In addition, we cannot use an efficient algorithm in secure computation without careful consideration of how not to violate the security. However, the performance of secure computation has been greatly improved recently, and secure computation is expected to be increasingly used in practice. In this paper, we introduce several techniques to carry out secure computation and algorithms to improve the performance of secure computation.

This article surveys a recently introduced data compression method known as compression by substring enumeration (CSE) and its related topics. CSE is an offline, lossless universal code, which encodes an entire data sequence as a single block without using prior knowledge of the information source. It is strongly related to existing offline compression methods such as enumerative codes, the block-sorting method, and the antidictionary method. Various interesting characteristics are seen in several fields from information theory to algorithms and data structures in the development of CSE. CSE leads to a better understanding of a class of offline lossless compression algorithms.

Facing a super-aging society, there is an urgent need in Japan suggested to shift from passive medical care to preventive medicine and health management, and therefore, a strong desire for healthcare monitoring that is available anytime and anywhere. Firstly, this paper focuses on core technologies of wearable healthcare monitoring, including physiological information sensing. Then, cuffless wearable devices for blood pressure sensing and stress monitoring are reviewed, which have recently been attracting a lot of attention. Concerning the research and development of physiological information sensing, it is important to achieve the following two technologies:(1) unconstrained monitoring using wearable sensors (hardware) and (2) high-order information extraction of physical and psychological conditions from multivariate analysis of sensor data (software).

Quality-oriented software management technologies and their sustainable improvements are the key factors for ensuring the success of software projects and developing high-quality software. Focusing on the four topics related to software reliability measurement/assessment and management technologies, we explain their technologies from the viewpoint of quality-oriented software management with some examples of applications to actual software project data.

This article discusses wireless networks from the viewpoint of queueing theory. First, queueing theory and its scale effect are explained. Then, it is discussed how to obtain the scale effect in wireless networks. Finally, the following examples of applications of queueing theory are described: simple analysis for contending and hidden nodes, dynamic channel selection in vehicular ad hoc Networks (VANETs), and a performance comparison of wireless networks using single-user/multiuser multiple input multiple output (MIMO) systems.