We analyze the amount of stress change during refraining from going outside caused by the new coronavirus. The relationship between the amount of stress change and various factors obtained from the questionnaire survey be examined using correlation analysis and quantification method I. The questionnaire survey is conducted in Tokyo and Nagano prefectures, and differences between the regions are investigated. The results of the analysis showed that the amount of stress and vitality changes were related to job satisfaction, home satisfaction and changes in the range of behaviors before and after self-restraint.

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In the present study, the standing tape dispenser used in regardless of the static friction coefficient and the shape with the mounting surface, the installation site and the length of the tape was proposed. The performance was evaluated. In the proposed tape dispenser, the tape was peeled in a lateral direction, the tape was extracted perpendicular to the mounting, and the tape was cut in a downward direction. The proposed tape dispenser was fixed at the mounting, by the static frictional force when the tape was peeled, by the gravity force when the tape was extracted, and by the reaction force from the mounting when the tape was cut. The installation site was not limited without requiring the iron mounting, and another fixing device in the mounting different from the proposed tape dispenser. The proposed tape dispenser was created actually to evaluate the performance. In the process of peeling the tape, extracting the tape and cutting the tape, the created proposed tape dispenser was not moved at lower values of the static friction coefficient and the patterned indented shape of the mounting. The length of the tape over 8.6 cm was created.

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The purpose of this study is to develop a decorative laser marking system on stainless steel. In the conventional research, since the thickness of the oxide film is controlled in order to reflect the interference color, there is a problem that the number of colors is small and it is difficult to use it for decorative purposes. Therefore, we propose a method to reflect various colors by forming a microstructure consisting of two types of oxide films. The proposed method demonstrated the improvement of color resolution due to the effect of simultaneous color mixing, and developed a system that can mark stainless steel blades.

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We propose a method to estimate the self-position from the distance between the poles and the LiDAR-equipped robot by placing poles with known coordinates at the four corners of the map. This method can be used for self-position estimation outdoors, where the scan data acquired by LiDAR is not fixed in time and position. Although it is possible to perform self-position estimation if at least two poles are used, we prove that using four poles improves the maximum error of x-coordinate by 41% and y-coordinate by 83%. We also prove that the maximum distance error from the true value can be reduced to 3.2 cm.

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Frequency-Modulated Continuous-Wave (FMCW) technique has been introduced into digital holography (DH) by using an injection-current-induced frequency modulation of a laser diode (LD) as a light source. Since the frequency of beat signals observed in time series holograms captured by a high speed digital camera depends on the optical path length difference between the reference and the object light waves, the introduction of FMCW technique into DH makes it possible to multiple record the object information in time-frequency domain. By the technique, a polarization state of the object wave transmitting through a PMMA sample was investigated using the proposed technique in which the object wave interfered with two orthogonally linearly polarized reference waves having the different optical path lengths.

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The deep hole processing of the high die steel is important technique for manufacturing the die for aluminum die casting for alternative vehicles. The automatic deep hole processing for small diameter is difficult. The control parameters are important for the automatic deep hole processing because the inadequate parameters cause the drill breakage and the productivity decrease. Currently, the expert technicians having excellent skills manually carry out the deep hole processing to the die steel. If the automatic control parameters for the machining center can be obtained based on the skills of expert technicians, the automatic deep hole processing is become possible and the productivity improves. In this study, the appropriate feed speed and the appropriate cut depth in each step were investigated as the suitable control parameters based on the expert technician’s skills. The automatic deep hole processing tests were carried out with a machining center via the suitable control parameters. The product sample with many small deep holes was processed with the machining center via the suitable control parameters and the previous control parameters. The machining time via the suitable control parameters were 30 % lower than that of previous control parameters and the productivity improvement was achieved.

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In this paper, we deal with an optimization problem of conveyance velocities and conveyer belts of a cascaded conveyer belt system. The aim of this system is to transport products to fit in with periodic motion of lower process of the conveyor line by using the conveyer belts without sensors which can detect the products continuously. Therefore, it is important to move the products without slipping and to determine the number and lengths of conveyer belts that realize the conveyance appropriately. This paper shows that this problem can be formulated as a linear programming problem and that the formulation makes the optimization of the conveyance velocities and the conveyer belts possible. The effectiveness is illustrated by some simulations.

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The agricultural workforce in Japan has been continuously decreased since 1950, and the aging of the agricultural workforce is getting serious. Hence, the development of burden reduction technology in the agricultural field has become a very important task in order to maintain agricultural production. In this study, we aim to develop an autonomous carrying vehicle to realize the carrying of harvest without workers. This vehicle is intended for use in sloping orchards and realizes autonomous carrying with AR markers and two-dimensional LRF. Also, an obstacle avoidance function and an operating status notification function are installed. As a result of the verification experiment using the vehicle, we confirmed that unmanned carrying could be realized. The effectiveness of the obstacle avoidance function and the operating status notification function is also confirmed. This vehicle can be used not only for transporting harvested products but also for orchard monitoring and pesticide spraying. Therefore, further efficiency of agricultural work can be expected.

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In Japan, where the birthrates are declining and the population is aging rapidly, there is a critical shortage of medical and nursing personnel to support the elderly. Under these circumstances, various monitoring systems using robots have been proposed. In this study, we focused on the path planning method for robots and applied Deep Reinforcement Learning, which has been shown to be capable of creating a path that takes various environmental information into account, to a monitoring robot. In this paper, in order to recognize a map as an image in an environment where the destination is moving, we perform path finding using a Convolutional Neural Network (CNN) and three types of deep reinforcement learning algorithms, which are effective for image recognition, and evaluate each path finding method by simulation.

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The study of refrigeration systems is attracted topics. Refrigeration is the generation of cooling to maintain a particular product or space at a temperature lower than the ambient temperature. For realizing good control performances, a model-free control is desired. However, a standard PID control may not realize good control performance since refrigeration systems have strong nonlinearity. In this study, we proposed a temperature control based on Fictitious reference feedback tuning(FRIT). The validity of the proposed method is verified through numerical simulation of PID Benchmark 2018.

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We have been in aging society for years. Aging population causes an increase in the number of elderly population. And declining birthrate causes a decrease in the number of caregivers. These cause the decline in the quality of nursing home. So that is one of social issues that needs solution urgently. From the background of our society, especially home healthcare has become more important due to the issue. To support home healthcare, we have developed a device and its system to make home healthcare easy. The device is a smartwatch which measures pulse on wrist. Its system calculates breathing rate and heart rate from the pulse data at the same time. The algorithm was Fast Fourier Transform (FFT). And the system used preset frequency ranges to extract breathing rate and heart rate. In this study, we introduce new system for the device to set the frequency ranges automatically. So, this time, we put wavelet algorithm into the device system, instead of FFT. With wavelet algorithm, the device system sets frequency ranges of breathing rate and heart rate. Then it extracts each data, even if the ranges are fluctuating. So, it calculates breathing rate and heart rate with robustness.

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Recently home healthcare has become more important due to aging population and declining birthrate. It also causes shortage of nursing home services. On the other hand, generally it is hard to find patients who have the sleep apnea syndrome (SAS) or the cardiac arrhythmia. Because those symptoms happen during sleep or sudden in everyday life. Also, it is said that patients tend to have the SAS and the cardiac arrhythmia at the same time. So sometimes they are required having diagnoses at a hospital for a long time to find the symptoms. For supporting home healthcare, many handy devices have been developed. And those usually measure a single vital sign such as heart rate. But for instance, measuring breathing rate is required to find the SAS. Or it is better to also measure heart rate at the same time for the cardiac arrhythmia which sometimes happens with the SAS. Thus, we focus on supporting home healthcare. In this paper, we show a handy device we created to diagnose multiple symptoms at the same time automatically by measuring breathing and heart rates for a long time.

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In this paper, the authors report on the prototype of the low cost of the cutting tool edge polisher that can correspond to the shape and size of any tool. In a previous study, the authors developed a tool edge polisher for wear research. However, it was difficult to use at the production site because it was an expensive machine that could handle only one size and shape. In this work, we prototyped the low-cost polisher based on a small commercially available milling machine that moves the polishing buff using a numerical control. As a result, the cutting edge of the tool was polished uniformly and smoothly. In addition, cutting experiments with polished tools have shown that the flank wear width of the cutting edge is smaller than with unpolished tools.

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Wastewater monitoring is necessary to preserve the quality of water in publicly water bodies. In particular, the presence of colored pollutants in wastewater inhibits the photosynthesis of seaweed, and therefore requires adequate treatment for its removal. We developed a surface-enhanced Raman scattering (SERS) sensor for the detection of color-polluted water. Silver particles on a quartz substrate were grown via mist chemical vapor deposition; this substrate was built into the sensor to enhance its Raman-scattering signals. Aqueous solutions colored with a single dye were detected at concentrations as low as the ppb level, and the intensity of their SERS spectra decreased with the dye concentration. Additionally, we evaluated the performance of the SERS sensor using mixed dyes dissolved in river-water, making assumptions suited to practical occurrences results demonstrated that our sensor depicts the molecular features of each dye in the river-water sample, clearly detecting them at concentrations as low as the ppb level. Therefore, this study proved that SERS can be applied in an environmental spectroscopic sensor.

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A compact electrochemical sensor system was constructed by using basic electrical and electronic circuit design and a microcomputer for the control. The measurement accuracy was almost the same as the one obtained with a commercially available potentiostat which is a typical electrochemical measurement equipment. The proposed system implements a function that displays the measurement results immediately using Processing a programming language for visual design. The low manufacturing cost is also one of the attractive features of this system. In other words, this system is readily available and compact so that it can be used anywhere. This suggests that such a system should be highly useful in various industrial fields.

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