An annealing machine in which the Ising model is used to solve combinatorial optimization problems is proposed. In the annealing machine, combinatorial optimization problems are mapped to an Ising model that expresses the magnetic spins, and the problems are solved using the Ising model’s convergence property. A CMOS annealing machine, which implements annealing machines with CMOS semiconductor circuits, effectively solves the problems through a combination of deterministic and stochastic operations. An examination of a prototype chip confirmed that the CMOS annealing machine effectively yielded an approximate solution, and the power efficiency of its calculation was better than that of conventional von Neumann computers. In this article, a whole system for the realization of the technique is also described.
In the modern world, multiple devices are connected through communication networks. Consequently, control methods using communication networks have attracted much attention. A control system where plants and controllers are connected through communication networks is called a networked control system and has been widely studied. In this article, we introduce event-triggered and self-triggered control methods for networked control systems. Using these methods, low communication load and high control performance are achieved.
The shear-vibration resonance frequency of an AT-cut quartz crystal shows ultrahigh temperature stability on the order of 1 ppm/K. When molecules are captured on the oscillator surface, the resonance frequency decreases because of the mass-loading effect. Because the shear vibrational mode allows vibration even inside a liquid, the AT-cut quartz resonator has been adopted for biosensors. It has been recognized that the mass sensitivity significantly increases upon thinning the oscillator, but achieving this has never been straightforward because of the heavy electrodes and wires attached directly on the surfaces. We thus developed wireless-electrodeless quartz-crystal-microbalance (QCM) biosensors; instead of electrodes, we used antennas for noncontact measurement of the resonance frequency and achieved significantly improved mass sensitivity. Here, I introduce the principle and configurations of the wireless-electrodeless QCMs, including the MEMS process for mass production.
Image colorization has been studied to obtain color images from monochrome images. Recently, deep-learning-based colorization algorithms have enabled the automatic colorization of an image. In this manuscript, we describe some image colorization algorithms, which can be classified into three kinds on the basis of the difference in the intervention by the user: some color scribbles by the user, the source color image provided by the user, and no intervention of the user. Furthermore, colorization applications, such as medical image processing, animation production, and color image coding, are also described.
In this report, an overview and case studies of the vehicle-to-vehicle communication and ranging system using the spread spectrum technique called the boomerang system and improved systems are introduced. The vehicle with the boomerang system can communicate with another vehicle also with this system and, at the same time, the distance between the two vehicles can be controlled. The systems introduced here are important for the practical use of safe driving support systems, which fall under the field of intelligent transport systems (ITS).