Semiconductor integrated circuits use ultra-flat substrates called wafers, in which minute irregularities are eliminated to the utmost limit. To produce such a flat substrate, a polishing technique called chemical mechanical polishing (CMP) is used. In particular, polymeric polishing pads used for CMP facilitate the retention of polishing slurry material and the discharge of polishing products. The objective of this study was to develop hollow microcapsules to form polymer-based CMP polishing pads with superior strength. Hollow microcapsules were prepared with chlorobenzene as the core material and a melamine-formaldehyde skeleton as the wall material, and then removing the chlorobenzene by a subsequent drying process. Specifically, this study examined the effects of microcapsule preparation conditions (stirring speed during emulsification, concentration of capsule wall material, and volume ratio of dispersed phase to continuous phase) on capsule morphology and average particle diameter, the relationship between average particle diameter and bulk density, and drying methods to maintain a hollow structure. As a result, hollow microcapsules with an average particle size of 5-30 µm and a bulk density of less than 0.3 g/cm3 were achieved.

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In recent years, nursing and welfare facilities have been facing a growing shortage of nursing care workers due to a decline in the working-age population caused by a falling birthrate and aging population. ICT is regarded as one of the solutions to these issues in nursing and welfare facilities, however, issues that arise from ICT have also surfaced. One such problem is the slowdown of communication speed caused by congestion. In this study, network simulations were conducted, and the performance of Reactive TCP, an implemented congestion control algorithm, was evaluated. In the experiment, throughput and the volume of packet losses were measured as the communication volume increased. Loss-based and delay-based schemes are used by Reactive TCP depending on the situation, and packet loss is used as an indicator of congestion. The algorithm is normally operated on a loss basis, and communication is continued on a loss basis if congestion is not detected. When congestion is detected, a switch to delay-based processing is made, and loss-based communication is resumed. Three sets of data were used in the experiment, labeled data (1) through data (3). The algorithm for data (1) is switched when a packet is discarded, for data (2), the switching timing is delayed, and for data (3), the switching timing is accelerated. It was shown by the experimental results that the algorithm in data (1) was highly effective in both throughput and volume of packets lost. However, since this differs from the actual internet environment, further experiments in the actual internet environment need to be considered.

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Recently, the advancement of virtual reality (VR) technology has led to its increased utilization in the field of education. Particularly, experimental practices in primary and secondary education play an important role in enhancing students’ interest and understanding. Applying VR technology to these practices enables the simulation of situations that are difficult to reproduce in real life while maintaining experiential learning effects. On the other hand， to implement VR in educational settings, it is crucial to develop devices that do not depend on media literacy and to provide highly immersive experiences that combine enjoyment and richness. In this study, we developed the Thermal Grip VR Controller (TGV-C), which incorporates a peltier module-based heating and cooling presentation system and an intuitive input system using a bending sensor. The temperature presentation positions are the pads of the thumb and index finger, and the input operation is performed using the bending sensor of the middle finger. Evaluation of users’ reaction speed to the TGV-C’s temperature change function revealed a delay of 5.27 seconds for warm sensation presentation and 2.28 seconds for cold sensation presentation. Furthermore, comparative verification with an existing controller (Meta Quest Touch Plus controller: MQT-C) indicated that the TGV-C enhances the sense of immersion and presence in VR experiences while reducing physical fatigue during use. However, there is still room for improvement in terms of production costs and design. Moving forward, it is necessary to consider the application to VR chemical experiments and to conduct efficacy verification for various user attributes, with a view to applying the TGV-C in the field of education.

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This study fabricates 50SiO2·50GeO2 and 50SiO2·(50-x)GeO2·xR2O (R: Na, K, Rb, and Cs, x = 5–40) glasses using the conventional melt-quenching method. Their photoluminescence characteristics were investigated by measuring their emission and excitation spectra. In the case of the 50SiO2·50GeO2 glass, a sharp and significant emission band attributed to the Ge2+ center appeared prominently at a central wavelength of 395 nm, corresponding to an excitation band at 250 nm. However, the emission spectra of 50SiO2·(50-x)GeO2·xR2O glasses revealed distinct emission bands around 480 and 540 nm, which differ from the 395 nm emission band typically associated with the Ge2+ center. These emission bands indicated coordination of the Ge2+ center with alkali ions. The basicity of alkali oxide, which is linked to its ability to provide O2– ions, influenced the coordination of the Ge2+ center with alkali ions in the glasses, resulting in a decrease in the amount of coordination. Consequently, the intensity of the emission bands varied depending on the quantity and type of alkali components present.

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This study investigates the effectiveness of essential oils in relieving chronic pain in patients with Parkinson’s disease (PD). Chronic pain affects around 22.5 % of the Japanese population, and its prevalence is rising due to an aging population. Traditional pharmacological treatments often fail to provide sufficient relief, which is leading to interest in alternative therapies such as aromatherapy. In this study, gas chromatography was used to analyze the chemical composition of four domestically produced essential oils: lemongrass, eucalyptus, bergamot, and kuromoji. Active compounds with potential pain-relieving and calming effects were identified. The suitability of these oils for the Japanese population was assessed by comparing their aromatic profiles with those of foreign produced oils. The analysis revealed several bioactive compounds in the essential oils. Lemongrass and eucalyptus oils contained significant amounts of citral and 1,8-cineole, both known for their pain-relieving properties. Bergamot and kuromoji oils had high levels of linalool, associated with calming effects. Additionally, the domestically produced oils showed aromatic profiles that were more in line with the preferences of the Japanese population compared to foreign produced oils. The essential oils studied contain compounds with potential analgesic and calming effects, indicating their potential for managing chronic pain in PD patients. The oils’ alignment with aromatic preferences of the Japanese population may improve acceptance and adherence to aromatherapy. Further clinical studies are needed to validate these findings and explore the therapeutic potential of these oils in chronic pain management.

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Currently used methods for selenium quantification include X-ray fluorescence spectrometry and inductively coupled plasma analysis. However, both methods require expensive equipment, specialized knowledge, making them unsuitable for simple on-site quantification. Therefore, in this study, we developed a simple and rapid method for selenium content determination based on methylene blue reduction. We investigated the feasibility of selenium quantification using a superabsorbent polymer supporting methylene blue. When a selenium solution was added to the polymer, a correlation was observed between the fading time of methylene blue and selenium concentration in the range of 0-10 ppm. These results suggest that selenium content in soil eluate can be quantified using the proposed method. Furthermore, this method enables the determination of selenium content in both aqueous solutions and soil samples. Additionally, it does not depend on temperature, making it suitable for quantifying selenium under various temperature conditions.

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It has been demonstrated that providing instructions during the execution of sports skills can influence performance outcomes. This study aimed to explore the impact of instructions on operational performance in a controlled experimental setting, thereby enhancing our understanding of how different types of instructions affect skill execution. The experiment was conducted indoors, with participants seated in chairs. Before initiating the task, participants were given a printed sheet of instructions and directed to adhere to the guidelines during the operation. The task involved using a pipette to transfer a specific volume of water from a beaker to a tube. The instructions were designed to include conditions emphasizing either operational accuracy or speed. Additionally, a total of five distinct instruction conditions were created, varying in phrasing but sharing the same underlying intentions. Task performance was assessed by measuring the time taken and the weight of the transferred water for each instruction set. Cluster analysis of task duration and accuracy divided participants into two distinct groups: those whose accuracy varied across instructional conditions and those whose accuracy remained consistent. In the group where accuracy fluctuated, a trade-off between task duration and operational error was observed. Notably under conditions prioritizing accuracy, performance declines led to increased errors. Conversely, in the group where accuracy did not fluctuate, task duration varied while the error in the set value remained consistent.

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Helping behavior is intended to increase other people’s well-being without expecting substantive rewards. Although a helper performs helping behavior for the target’s benefit, the behavior also affects the helper. For instance, not only compassionate feelings, but also conformity and norms can produce helping behavior. However, people tend to over-estimate the value of helping behavior when the behavior stems from compassionate feelings. This study aimed to investigate the effects of helping behavior that compassionate feelings elicit on the helper’s inner state. In Studies 1 and 2, participants worked as a paid volunteer transcriber for people with hearing difficulties and for other people with difficulties in listening to spoken language (compassion condition) or as an out-sourcing paid job worker (neutral condition). Questions about self-esteem, psychological well-being, intention to help, one’s own morality, work efficacy, and the respondent’s demographic were asked after the task (dependent variables). In testing the original hypothesis, results from a series of t-tests were not significant. An ANOVA, an exploratory analysis, showed that participants in the compassion condition had a higher level of some dependent variables when they had past volunteer experience in comparison to those who had no experience. Although the original hypothesis was not supported, this study found that the experience of volunteering is important for feeling compassion and the consequential actual helping behavior. Among the findings of this study, notably manipulating compassion experimentally (not as individual difference) is an important contribution to future research.

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NaxCoO2 is a widely used cathode material for sodium-ion batteries, which are expected to replace lithium-ion batteries. In this study, NaxCoOα·nH2O crystals were prepared from Na3[Co(NO2)6] using a complex pyrolysis method. According to thermogravimetric (TG)–differential thermal analysis results, Na3[CoIII(NO2)6] was pyrolyzed into a mixture of NaNO3, Na2O, and CoII,III3O4 at 250-350 °C and Na2O and NaCoII,IIIO1.83 above 800 °C. It was found that Na3[Co(NO2)6] existed in the form of thin Co-rich hexagonal platelet crystals embedded into Na-rich or amorphous crystals after heat treatment at 700 °C for 2 h. After further washing with deionized water, only the thin hexagonal platelet crystals were observed, whereas the Na-rich or amorphous crystals disappeared. X-ray diffraction measurements revealed that the hexagonal platelet crystals consisted of a single γ-NaxCoO2 phase. Its chemical composition estimated via energy-dispersive X-ray spectroscopy and TG analysis was Na0.34CoO1.39·0.20H2O. The intragranular and intergranular resistivities of Na0.34CoO1.39·0.20H2O crystals compressed at 100 MPa were 200 and 80 Ω·cm, respectively, at room temperature. Furthermore, Na0.34CoO1.39·0.20H2O powder can be potentially used as a positive electrode in Na-ion batteries.

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[in Japanese]

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In this study the power generation characteristics at room temperature of a fuel cell using the compacts of zirconium phosphate (γ-Zr(PO4)(H2PO4)･2H2O) and alumina (Al2O3) powders carrying phosphoric acid (H3PO4), which exhibits high proton conductivity, as the electrolyte were investigated. When using a proton-conducting γ-Zr(PO4)(H2PO4)･2H2O electrolyte and a <5%Pt-C + H3PO4> composite electrode, the open circuit voltage (OCV) was 0.55 V and the maximum power output (Pmax) was 0.020 mW･cm–2. When using a <γ-Zr(PO4)(H2PO4)･2H2O + H3PO4> composite electrolyte with improved proton conductivity and a <5%Pt-C + H3PO4>, the OCV was 0.73 V and the Pmax was 2.5 mW･cm–2. When using a <Al2O3 + H3PO4> composite electrolyte with insulating Al2O3 instead of γ-Zr(PO4)(H2PO4)･2H2O and a <5%Pt-C + H3PO4> composite electrode, the OCV was 0.75 V and the Pmax was 7.0 mW･cm–2. Therefore, it can be concluded that both γ-Zr(PO4)(H2PO4)･2H2O and Al2O3 powders function only as carriers for H3PO4. When the effect of average particle size on power generation characteristics was investigated using Al2O3 powder with different average particle sizes (0.3 µm, 0.7 µm, 1 µm, and 10 µm), Al2O3 powder with an average particle size of 0.3 µm achieved the best power generation characteristics (OCV: 0.84 V. Pmax: 14 mW･cm–2). Based on these results, we proposed a proton fuel cell using inorganic electrolyte powder that can be fabricated at room temperature and in air in an experiment lasting approximately three hours, and whose power generation characteristics can be measured.

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Automatic valet parking using learning function is proposed in this study. The number plate (vehicle registration plate or license plate) of each vehicle is read using a camera when entering and leaving the parking lot. The entering and leaving date and time of each vehicle can be searched by using the plate characters. An image recognition technic and a timer function are used at this time. The license plates are stored in a database. When a customer is entering the parking lot, the reception number and the customer’s vehicle plate number are stored on a magnetic card and handed over it to the customer. When leaving the parking lot, the customer goes to the exit and inserts the magnetic card, and the driver completes the payment process. It is the time when the leaving process is completed. The entering date and time and the leaving date and time are stored together in the database. It is important to shorten the time (leaving time) obtained by subtracting the requested leaving time from the actual leaving date and time in the automated valet parking. The patterns and characteristics of users can be extracted through a data-mining technique by utilizing the created database. Some new values can be added based on the characteristics of the customer’s car using this system. These will enable the functionality and efficiency of the system to be improved. For example, if it is known that a registered customer’s vehicle tends to stay parked there all day after entering the parking lot, the system will park the vehicle in a farthest location from the exit (a location with the lowest priority), allowing other vehicles to leave smoothly. The priority can be given to other vehicles. The vehicles that tend to leave the parking lot in a short time are conversely parked in the highest priority location (closest to the exit). This process can improve the time efficiency of leaving. When the leaving date and time of a vehicle can be known in advance, it can be moved closer to the exit and the time to leave can be shortened. In this study, a simulation system is constructed to improve the efficiency of automated valet parking using the above-mentioned learning function.

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