Card-based cryptography enables us to perform secure multi-party computations using a deck of physical cards. Since it was shown in 1989 that secure AND computation can be carried out with five cards, many card-based protocols have been proposed. Card-based protocols can be easily executed without a computer, and their correctness and security are easy to understand for non-specialists such as high school students. This manuscript gives an overview of the evolution of card-based cryptography.

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Compilers must be highly reliable since they are infrastructure tools for software development. Although compilers are tested intensively using test suites consisting of a huge volume of test programs, it is theoretically impossible to validate compilers completely with a finite set of test programs and many bugs have been reported in open-source compilers such as GCC and LLVM/Clang. Recently, some tools for the random testing or fuzzing of compilers have been developed and their effectiveness has been demonstrated. This article surveys the technical and practical aspects of the tools and discusses the challenges and future direction of compiler fuzzing.

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To understand the confusing usage of "hacker" and "hacking" clearly, we explore how public images of hackers have developed and try to place these public images in a historical framework. The social anxieties of each decade are projected on hackers. Images have been constructed not only by the mass media but also by computer professionals and academics. Focusing on hackers can provide an alternative historical perspective of computing and future role models and public images of computing.

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Basic features of aerial ultrasonic waves are discussed and a method of generating ultrasonic waves of high power at a high efficiency in air is described. Furthermore, techniques to generate high-intensity ultrasonic waves using these radiation waves are described. We give a basic outline of a practical ultrasonic source and discuss the basic characteristics of the sound source. In addition, we outline various applied technologies that use a specific effect of high-intensity aerial ultrasonic waves.

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The virtual slide has been developed and is a key to innovation in digital pathology. The image quality of digital pathological images is one of the most important issues in the practical use of virtual slides since it greatly affects the accuracy of pathology diagnosis and image analysis. In this paper, we discuss the importance of image quality in digital pathology and an approach to the standardization of digital images by employing image analysis techniques. As a contribution to the standardization of digital pathological images, we introduce a color correction method and an algorithm for image quality assessment.

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Since the basis of Hölder's inequality was found by mathematicians, i.e., independently by Rogers in 1888 and Hölder in 1889, the inequality has been frequently utilized as a basic inequality in mathematical analysis such as functional analysis. However, surprisingly, no physical interpretation of the inequality was introduced until 2014. In this article, I show that the inequality gives an elegant solution to a recent open nonlinear problem. It is also asserted that the inequality can be a fundamental basis in Tsallis statistics, studied recently in information and communications technology. Furthermore, it is argued that the inequality can make a useful addition to modern control theory.

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Recently, communication technologies for reliable remote control have become indispensable, and many communication technologies based on control theory have attracted considerable attention. In particular, networked control that considers the packet loss and transmission delay, and control-theory-based data transmission that considers the quality of the service of data transmission have been studied actively. In this paper, we introduce resource management technologies based on control theory for optical grids and cognitive wireless networks. For optical grids, the resource management technologies utilize PID control and model predictive control so that both computer resources and wavelength resources are utilized effectively. For cognitive wireless networks, on the other hand, the resource management technologies adjust the transmission power to utilize wireless resources effectively by utilizing PID control and model predictive control. In terms of the technologies, we explain how each network is modeled and how PID control and model predictive control are utilized.

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Spin-based integrated electronic devices utilizing both the spin and charge degrees-of-freedom of the electron, commonly known as spintronic devices, have been progressively explored. In particular, spintronic devices exploiting spin-current-induced magnetization dynamics, such as magnetoresistive random access memory (MRAM), spin torque nanooscillators (STNOs), and ferromagnetic nanowires, are expected to surpass CMOS devices in their ability to reduce power consumption and achieve high functionality. In this article, we propose a dynamical system design approach for spintronic devices, in which device dynamics underlying the operational mechanism of target devices are treated as dynamic systems from a mathematical viewpoint. Our aim is to establish a universal design and control theory independent of specific features of materials and substances. First, we overview the dynamics-based design approaches, which are a foundation for our approach, developed in the field of nonlinear science and technology. Next, we briefly review the operating characteristics of representative spintronic devices, such as MRAM and STNOs, in view of the aspects of dynamical systems. Furthermore, we present several case studies of our design approach for optimizing various synchronization schemes for STNO arrays. Finally, we discuss the extendability of our approach to the optimal control of advanced spintronic devices.

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