半導体および関連材料，微細加工技術，実装技術，検査技術など，電子材料関連技術の重要性はIoT時代になってますます大きくなっている。材料の多様化に加えて，材料の微細形状に基づいた機能の発現や，光技術との融合，印刷による回路形成など，関連技術との協奏的な発展により，

Spherical-shaped submicron-sized particles (SMPs) of noble metals are an ideal material to prepare electronic wires using ink-jet printing. Platinum SMPs (PtSMPs) must be a better material than gold SMPs (AuSMPs) used in high temperature conditions, because of the higher melting point of platinum than that of gold. However, differing from AuSMPs, no convenient PtSMP preparation method have been developed so far. In the present study, we have applied the laser melting in liquids method (LML), which has been used to prepare SMPs of various materials, on the preparation of PtSMPs. The results showed that PtSMPs were successfully obtained by laser irradiation at 266 nm for platinum nanoparticles stabilized by a small amount of sodium citrate via the laser-induced agglomeration. It was also found that PtSMPs of the similar size were obtained when laser wavelength was changed to 355 nm, although the irradiation time necessary to induce NP agglomeration using 355 nm laser irradiation became longer than that using 266 nm laser irradiation. This laser wavelength dependence was explained in terms of the size-dependent heating efficiency of platinum particles.

We report prediction, synthesis and characterization of new carbon-based materials related to organic molecular materials. Five topics are described: Ferromagnetism of two-dimensional B-C-N systems, comparison between organic molecules and carbon atoms embedded in hexagonal boron nitride, photocatalysis of graphitic carbon nitride, and high-pressure synthesis of polymeric carbon from π-conjugate organic molecules.

With the aim of developing new electronic functionalities for flexible devices, a transfer process for the preparation of flexible conductive thin films was examined using epitaxially grown anatase Nb: TiO₂. Using pulsed laser deposition, water-soluble Sr₃Al₂O₆ (SAO) was deposited on a single-crystalline LaAlO₃ (100) substrate (LAO) as a sacrificial layer, followed by the epitaxial growth of anatase Nb: TiO₂ on the sacrificial layer. The Nb: TiO₂/SAO/LAO multilayer sample bonded onto a flexible polymer sheet via an adhesive tape was soaked into distilled water to transfer the epitaxially grown Nb: TiO₂ thin film from SAO/LAO to the polymer sheet. The transferred anatase Nb: TiO₂ thin film retained the clear X-ray diffraction peaks. Moreover, the areal transfer ratio was almost 100%, without the generation of significant impurity phases during the transfer process. On the basis of these results, the examined process was found promising for the preparation of flexible anatase Nb: TiO₂ thin films. The voltage drop - current characteristics were measured successfully at room temperature for the transferred anatase Nb: TiO₂ thin film using the standard four-probe method with gold electrodes.

Cylindrical structure of micro-swelling silicone rubber of approximately 1 µm diameter and 1.5 to 2 µm height was fabricated by the 193-nm ArF excimer laser-induced photodissociation of Si-O bonds of silicone rubber. To be periodically, single layer of silica glass microspheres was aligned on aluminum-coated silicone rubber during laser irradiation. The silicone rubber underneath each microsphere photochemically swelled, after laser-ablating aluminum to limit a diameter of the swelling. The aluminum also adjusted a focal point to the surface of silicone rubber to form a hole approximately 0.5 μm diameter centered at each the swelled silicone rubber. A purging O₂ molecules in the laser beam path by N₂ gas and lowering the laser pulse repetition rate were effective for fabricating the regular cylindrical structure. The regular cylindrical structure of micro-swelling silicone rubber showed superhydrophobicity.

We have analyzed the laser micro welding data for stainless steel (SUS304) by using the Hablanian plot. We have determined the standard fitting curve, which is obtained by fitting the laser micro welding data with a cubic polynomial, and the fitting difference (ΔLog₁₀(Vd/K)) in Log₁₀(Vd/K) between the standard fitting curve and the corresponding experimental data. When ΔLog₁₀(Vd/K) is equal to 0, we can precisely predict penetration depths by using the standard fitting curve. We have investigated the dependences of ΔLog₁₀(Vd/K) on penetration depth, welding speed, laser power, and spot diameter. The following findings could be derived. (1) The standard fitting curve for micro welding was mostly corresponding to that for macro welding. (2) ΔLog₁₀(Vd/K) had negative values above penetration depth of ~0.7-0.8 mm. The deeper penetration depth became, the more markedly ΔLog₁₀(Vd/K) decreased. (3) It is essential for accurate prediction of penetration depth to collect welding data for each spot diameter and to obtain the fitting difference ΔLog₁₀(Vd/K) for each spot diameter. (4) We showed that prediction of penetration depth with correction using ΔLog₁₀(Vd/K) data for each spot size is available.

We have aimed to apply epitaxial Pb(Zr_0.52, Ti_0.48)O₃ (PZT) thin films of ferroelectric and piezoelectric properties to flexible and wearable ultrasonic devices. To realize the flexible epitaxial PZT thin films, PZT thin films were transferred onto flexible printed circuit (FPC) composed of flexible polyimide sheet and Cu electrodes. To adhere PZT thin films to Cu electrodes of FPC, we used copper foil double-coated conductive adhesive tape. Buffer layer of Pt (60 nm) between PZT thin film and adhesive tape was quite effective to avoid serious exfoliation and cracks on the transferred PZT thin film. Transferred epitaxial PZT thin films onto Cu electrodes of FPC showed good electrical contact to the Cu electrodes and P-E hysteresis of ferroelectric characteristics was successfully measured.

This study aimed to evaluate the effects of psychological support utilizing mindful breathing on emotional load and task execution in college students using pulse waves. The subjects (20 students) were randomly divided into two groups (10 students each in the mindfulness and nonmindfulness groups). The number of answers and number of correct answers on a mental arithmetic task were compared between the mindfulness group and non-mindfulness group on day 1, day 5, and day 10. We also analyzed the results of fingertip plethysmography during the experiment. There was a significant difference between the number of answers and number of correct answers on the mental arithmetic task. The results for pulse wavelength suggested that mindful breathing was effective in suppressing sympathetic nerves. With regard to autonomic nervous system activity, the sympathetic nervous system was dominant before mindfulness practice and the sympathetic nervous system was suppressed after mindfulness practice. These results suggest that mindfulness may be useful for task execution and relaxation.

The engineering of skeletal muscle tissue has gained considerable attention in recent years because of its clinical applications, which include muscle replacement and treatment of muscle-related disease. Magnetic nanoparticle internalization by skeletal muscle cells has been proposed as a means of improving cell density. In this study, by embedding magnetic nanoparticles in mouse C2C12 myoblast cells to engineer a muscle tissue sheet, we evaluated the cellular uptake of magnetic nanoparticles and their effects on cell proliferation and differentiation. Our results show a tendency for decreased muscle fiber thickness in C2C12 cells with internalized magnetite nanoparticles. However, no change was found in the number of cells or differentiation.

In this paper, an inverse self-convolution algorithm for probabilistic distribution estimation is proposed. The Fourier transform of the self-convolution is the square of the Fourier transform of the original function. Therefore, the calculation of the square root of the Fourier transform makes it possible to calculate inverse self-convolution. However, it is not straightforward to calculate inverse self-convolution because the square root of the complex number is not determined uniquely. To deal with this difficulty, we preprocess the data sequence to enhance the smoothness of the discrete Fourier transform, and extrapolate the complex number by means of the polynomial approximation.

In the previous works, self-repairing control systems (SRCS) have been investigated that can automatically replace failed components with healthy backups so as to maintain stabilities. Fault detection can be exactly accomplished by using a discontinuous detection filter. However, from mathematical viewpoint, existence and uniqueness of the solution of the differential equation expressing the discontinuous SRCS are not assured. In this paper, taking the discontinuity of the detection filter into consideration, based on the Filippov method, the SRCS is modified in order to have a unique Filippov solution and to achieve SRC. In addition, by approximating the discontinuous filter with a continuous one, the continuous SRCS is developed that inherits advantages from the discontinuous SRCS.

With recent advancements in deep learning, the performance of hand gesture recognition (HGR) models has greatly increased, enabling reasonably accurate hand gesture detection with real time speed on modern desktop computer systems. Recently, there has been a growing interest in developing smaller and faster deep neural network (DNN) architectures suited for embedded devices. In this paper, we present a new DNN based end-to-end real-time control for home appliances. In purpose to gain reliable accuracy and execution speed, we proposed a new architecture by replacing the backbone of YOLOv3 and refining its head. The proposed network's performance showed advantages compared to popular object detection models. The model was incorporated into a HGR system for home appliance controls. The system provides a user friendly interface to register the correspondence between infrared signals and gestures. The proposed system takes images from a camera as input, recognizes gestures and produces corresponding infrared signals as output, providing a low cost system that can be used to control various home appliances under a complex environment. The code, trained tensor lite models and other software used in this research are available at https://github.com/appleyuta/RaspberryPi-HGR-System.

In the case of outcall sales at financial institutions, how to acquire potential customers that lead to new contracts has a direct bearing on the performance of sales representatives. Unfortunately, to acquire prospective customers in an efficient manner is, in many cases, an intuitive skill that is learned by sales representatives through experience, and is not part of the institutional knowledge of the company.

In this study, we propose a customer key person extraction method using customer data based on the premise of Business style "Referral Sales", which will introduce new customers from existing customers by utilizing organizational intelligence to enable customers to be able to anticipate new contracts. Specifically, in order to extract the customer key person, the chain property and diversity of the relationship between the customers, by the various edge of the Human Relations Network, to express the following contents.

(1) A character in an edge is represented as peculiar coefficients.

(2) Each node value is summation of characters in edges that are connected to the node.

(3) A key person value in one node is calculated from its node value and node values of the descendant nodes multiplied by a distance coefficient.

Customer key person is selected in order high key person value of a node. We call this above method HuRAT; Human Relational Analysis Technique.

In addition, as a result of applying this method to the actual business operations of the three insurance companies, and HuRAT improved the customer key person extraction rate compared with PageRank and the other conventional centrality indicator methods.

In this paper, the digitally controlled oscillator (DCO) using 1+n/k frequency divider (k>n) based on multi-phase clock is proposed. In this DCO, the time resolution of the output signal is the time of one phase difference of the multi-phase clock. Also, the oscillation frequency range is wide and the duty ratio becomes almost 50%.