International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

Considerable research has been conducted on measuring maximum tongue pressure, which is an index of tongue muscle strength that includes the relationship between tongue strength and swallowing function. Tongue pressure is the force with which the tongue presses a bolus of food against the palate and sends it into the pharynx. A low tongue pressure makes the aspiration of food more likely. In this study, we investigated the age-dependence of human swallowing function, as well as the swallowing function of female high school students in different courses, one in physical education and one in health and nursing.

In recent years, natural disasters have occurred almost annually in Japan, causing great damage. Power outages in disasterstricken areas have occasionally forced victims to resort to outdoor campfires or indoor candles for lighting. Prolonged bad weather during such events makes it difficult to safely secure lighting, which could have a negative influence on people’s health. To address this issue, we used white light-emitting diodes (LEDs) as the light source and fabricated handmade lanterns by filling a 500 mL plastic bottle with tap water and adding 1–2 drops of milk. In this study, an LED light source casing was constructed using a three-dimensional printer, achieving a stable light scattering effect. Red, green, blue, and yellow LEDs were used for the lantern, considering people’s preferences for colored handmade lanterns. An additional light source case was easily made from cardboard, and a bamboo light source case was also constructed.

Plasma-based ion implantation (PBII) is a surface modification technique that applies a negative high-voltage pulse to a sample immersed in plasma. PBII is suitable for samples with complex geometries, as its ion sheath conforms to the sample’s shape, ensuring uniform ion implantation. Due to its precise controllability, PBII is widely used industrially for surface modification and has promising applications for sterilization. We previously used PBII with oxygen gas to successfully sterilize heat-resistant spore. Here, we evaluated the use of PBII with HHO as the process gas for sterilization. Sterilization exceeding 7D was achieved at 10 min and 3 Pa. The enhancement of the sterilization efficacy was attributed to the synergistic effect of plasma and thermal energy, which emerged as a consequence of a temperature increase exceeding 100°C due to adjustments in pulse width and delay time. These results indicate the possibility for temperature control in PBII technology, which has potential application in sterilization processes.

When location was estimated using Sigfox’s Atlas Wi-Fi, the estimation error is several hundred meters. Meanwhile, when location was estimated using the Wi-Fi media access control (MAC) address and HERE’s API, the estimation error was ~10 m. In an Internet of Things device that obtains the Wi-Fi MAC address, the combination of exp32 and 100a was ~1/5th of the combination of Arduino R4 and Sigfox Shield.

The electric potential distribution is critical in Plasma-Based Ion Implantation (PBII), as it directly influences the energy and spatial distribution of implanted ions. Understanding the effects of key parameters, such as the applied voltage and gas pressure, on the formation of the electric potential distribution is essential for optimizing PBII-based sterilization. In this study, plasma simulations were conducted using PEGASUS (PEGASUS Software Co., Ltd.) to examine variation in the electric potential distribution under different operating conditions. The analysis focused on changes in the electric potential distribution and ion density in response to variations in the applied voltage. The results indicated that, increasing the applied voltage, led to an expansion of the negative potential region to approximately −500 V, highlighting the role of positive ions play a key role in the sterilization process. Furthermore, enclosing non–sample areas with a grounded structure reduced unnecessary plasma generation, potentially improving energy efficiency during sterilization experiments.

In recent years, natural disasters have frequently occurred in Japan, almost yearly, causing enormous damage. In Hiroshima Prefecture, heavy rains in August 2014 and July 2018 caused large-scale landslides. Power outages continued in the affected areas, and some survivors had been lighting campfires outdoors and using candles indoors. In times of disaster in which bad weather persists, it is difficult to safely secure lighting, which can adversely affect health. Lanterns can be created by putting a few drops of milk into a PET bottle filled with water and shining light from the bottle’s bottom. In this study, we used a light emitting diode (LED) as a light source to evaluate the luminance of handmade lanterns. Results suggested that when using tap water with one LED lamp and a 500 ml PET bottle, 1–2 drops of milk are suitable to achieve the optimal light scattering effect.

In this study, the Sigfox network and the Internet were employed to develop an Internet of Things device equipped with temperature, humidity, barometric pressure, and other sensors to measure different physical data. In addition, we attempted to control Sigfox communication by employing AT commands using the Arduino UNOR4 Sigfox module, and social implementation of the proposed system.

The Internet of Things (IoT) has seamlessly integrated more than a billion intelligent, interconnected devices into our world today, and is expected to accommodate soon hundreds of billions more such devices. This imminent proliferation heralds a profound transformation that stands to influence the electronics industry and many other sectors. Furthermore, integrating blockchain technology into IoT can impart genuine trust in the collected data. Hence, our research endeavors to harness this potential by applying it to hydrogenrelated data, which are expected to be critical in realizing a carbon-neutral society.
Specifically, our attention is directed toward utilizing an initial blockchain system to securely store data obtained from IoT devices equipped with hydrogen sensors that can communicate through Sigfox technology.

We report the results of measuring carbon dioxide (CO2) concentrations 140 times a day in habitable spaces using Sigfox along with temperature, humidity, and atmospheric pressure measurements. We design and fabricate a printed circuit board to integrate the sensor with an Arduino processor. Using the developed sensor, we estimate that if one adult male performs light work for 1 h in a typical living room [3.17 m (width 3.17 m) × 7.4 m (length 7.4 m) × 2.6 m (height 2.6 m) = volume 61.4 m3], the carbon dioxide CO2 concentration will increase by approximately 200 ppm. In the future, the developed sensor could be used for detailed human behavior studies in the context of CO2 concentrations.

We achieved a CT(ozone concentration(ppm) X exposure time(min) )value of 60, which can inactivate coronavirus from 1/10 to 1/100 by operating for 24 h at an appropriate ozone concentration (less than 0.1 ppm) using feedback control in the previous report. In this system, the only way to reduce the ozone concentration is the decomposition reaction of ozone in the natural world, and it was not possible to cope with the rapid increase in ozone. In this study, we investigated the reduction of ozone concentration using hydrogen. As a result, it was clarified that the concentration of ozone rapidly decreased even with about 1/100 of hydrogen’s explosion limit (about 4%).

Galvanic corrosion is a well-known phenomenon, which occurs when two different metals exposed to the same conditions exhibit differential corrosion rates. The corrosion process is accelerated by the exchange electrons between the metals. In this study, we created a novel layered structure of Cu and Al for efficient electron extraction through charge transfer. Using this Cu/Al laminated structure configuration and galvanic corrosion effect, an open-circuit voltage of approximately −160 mV was generated by measuring the difference in potential between the metal and a useful indicator of the electrochemical dynamics of the system. Furthermore, we effectively transmitted electrons between the metal in the layered structure, as demonstrated by the extraction of a charge of approximately 10−5 C. These results show the potential of using a laminated structure to take advantage of galvanic corrosion as energy generation and electrochemical sensing.

Using the Sigfox network, one of LPWA (Low Power Wide Area), and the Internet, we developed a temperature, humidity, pressure, and Internet of Things devices with different sensors to measure various physical data. It is much simpler to work with weather data when using OpenWeatherMap’s widely recognizable weather products. In this study, OpenWeatherMap’s meteorological data were captured every 15 minutes using are Sigfox communication, which is one of LPWA. These data were transferred to ThingSpeak using MATLAB analysis and time control of ThingSpeak.