Investigation of Applicability to Accident Tolerant Fuel (SiC cladding)

In the Fukushima Daiichi Nuclear Power Plant accident, nuclear fission reaction was stopped successfully after the earthquake. However, due to the failure of cooling by the station blackout, the cladding temperature rose and the cladding reacted with high-temperature steam, causing a hydrogen explosion, scattering radioactive materials over a wide area and injuring many residents. After this accident, many countries around the world started to develop cladding materials that do not generate hydrogen or generate little hydrogen even at high temperatures. Silicon carbide is one of the new cladding material candidates. It hardly reacts with high-temperature steam, and its melting point is much higher (2730℃) than the melting point (1852℃) of Zircaloy, the current cladding material. Moreover, the thermal neutron absorption cross-section is smaller than that of the Zircaloy alloy, and it is superior in terms of nuclear performance. On the other hand, since silicon carbide is a ceramic, when the diameter of the uranium dioxide pellet increases due to swelling at high burnup, the effect of pellet-cladding interaction (PCI) is a concern. In this study, the fuel behavior analysis code FEMAXI-8 was used to quantify the interaction between the uranium dioxide pellets and the SiC cladding at high burnup. It was confirmed that the cladding stress increased sharply when it exceeded over 70GWd/tU. Although the cladding stress is below the yield strength, it was understood that it is necessary to change the dimensions, shape, and material of fuel so that PCI does not become excessive in fuel design.departmental bulletin pape

Comparison on the Word-final Nasals between Japanese and English

Syllable final nasals have a language-specific duration among languages. There have been studies on syllable-final nasals but not on word-final nasals. This paper conducted a recording experiment to calculate the durational ratio of word-final nasals between English and Japanese. The analysis revealed that the ratio of syllable initial nasal to word-final counterpart in English was 1:1.53 and that of Japanese was 1:2.33 and found that Japanese word-final nasals are significantly longer than English ones. In future experiments, the recordings obtained through the current experiment are going to be edited and used to find out the durational threshold for Japanese listeners to recognize a word-final consonant.departmental bulletin pape

Predicting Land Price Changes in Fukui Prefecture with the Extension of the Hokuriku Shinkansen

This paper predicts the change in land prices in Fukui Prefecture following Hokuriku Shinkansen Fukui Extension. This analysis uses the land price change in Ishikawa Prefecture due to the Kanazawa extension of the Hokuriku Shinkansen line. Bullet of the Shinkansen tends to land prices to decrease by 0.074% in Kanazawa city. Based on the results of the regression analysis, this paper predicted the change in land prices for each location in Fukui Prefecture for the two years before and after the extension of the Hokuriku Shinkansen line. This study finds out that the extension of the Hokuriku Shinkansen Line enhances the agglomeration of the city: 1% increase in distance lead the change in land prices before and after the extension of the Hokuriku Shinkansen Line tends to change by -0.080%. The opening of the Shinkansen tends to increase by 0.025% where the use status of the land price location is residential.departmental bulletin pape

A Study of the former Matsuoka Clan members ISONO Tamiya family and SHIBUYA Gonzaemon family of Samurai Residences The Study on the Samurai’s Premises in the Matsuoka Clansman, part8

This paper was study of the samurai residences of the ISONO-Tamiya family and SHIBUYA-Gonzaemon family, former Matsuoka clan members. Both families lived in Osensui-Machi, the residential district of the senior samurai, for about 140 years after moving to Fukui Castle Town. Both the ISONO-Tamiya and SHIBUYA-Gonzaemon families serve as YORIAI-SEKI in the Fukui Clan. Both families were adjacent to each other in both Matsuoka and Fukui castle towns, with the Isono-Tamiya family to the north and the Shibuya-Gonzaemon family to the south.departmental bulletin pape

Condition of red tide appearance in Wakasa bay using satellite imagery

It is well known that red tides cause serious damage to the fishing industry, especially to culture businesses in Japan. If the appearance of the red tide can be predicted, there may be possible action to reduce fishery damage. In this paper, MODIS(Moderate Resolution Imaging Spectroradiometer) data were used to investigate the conditions under which red tides occur in Wakasa Bay. Results of the data analyses for the period from July, 2001 to December, 2019 indicate conditions, for the appearance of the red tide bloom in Wakasa bay as follows : (1) the threshold amount of chlorophyll-a is close to 3mg/m³, (2) the range of SST (Sea Surface Temperature) is limited in a range from 12 to 20℃. We also propose here to utilize MODIS band1 images corresponding to a red band with spatial resolution of 250m together with NDVI (Normalized Difference Vegetation Index) images which has also spatial resolution of 250m, for the confirmation of the red tide. In recent years, the occurrence of red tides in Wakasa Bay has been decreasing, which may be attributed to the improved water quality in the water surrounding Fukui Prefecture.departmental bulletin pape

The Student Guidance Office 2022 Annual Report : Support for Students in Third Year under COVID-19 Pandemic

This article reported statistics and some activities in the student guidance office as 2022 annual report, and examined the effects of support for students in third year under the coronavirus disease 2019 (COVID-19) pandemic. From the statistics, it was found that both the number of counseling and the number of users of the free space decreased in 2022 compared to 2021. This decrease was attributed to staff multitasking. In the third year of the pandemic, consultations related to academic issues, career paths, and employment accounted for 70%, suggesting a return to pre-pandemic conditions. Although the use of online counseling, which were widely utilized during the pandemic, decreased by 15%, it is expected that both online and face-to-face counseling will continue to be utilized after the pandemic subsides. in the future.departmental bulletin pape

Influence of Locomotive Organ Dysfunction on Fundamental Movements and Physical Fitness in Childhood

福井工業大学大学院工学研究科博士(工学)2022年度doctoral thesi

Mesophilic High-Solid Anaerobic Digestion of Municipal Wastewater Sludge-Effects of Influent Solids Content and Ammonia Stripping

This laboratory-scale study evaluated mesophilic high-solid anaerobic digestion (HSAD) of 9‒11%, 12‒15% and 17‒21% municipal wastewater sludge. At the hydraulic retention time of 20‒30 days, volatile solids (VS) reduction of 53.4‒56.6% and methane generation of 0.275‒0.296 NL/g-VS were obtained on average. At 12‒15% and 17‒21%, ammonia stripping of digested sludge and its return to the digester reduced the average total ammonia nitrogen (TAN) to 2,690 and 3,270 mg-N/L in digester, respectively, mitigating ammonia inhibition. The ammonia stripping, performed at 80℃, initial pH of 9 for 2‒3 hours and the return ratio of 100‒120%, showed TAN removal of 63.4‒74.5%. Microbial diversity became poorer with the influent level. Dewatering was achieved by the two-chemical conditioning with ferric chloride and an amphoteric polymer. Overall, the mesophilic HSAD in the wide and high solid range is feasible, as far as measures against high TAN and poor mixing is properly taken.departmental bulletin pape

Investigation of On-site Analysis for Heavy Metal Ions in Environmental Water by Combining Precipitation Technique and X-ray Fluorescence Analysis

In the present study, the analysis of Cr and Cd in sample solutions by a combination of precipitation technique and a handheld X-ray fluorescence spectrometer was attempted with a view to applying it to the on-site analysis of environmental water. As a result, it was found that Cr could be quantified to a level one order of magnitude lower than the permissible limit (0.5 mg L-¹) of the national effluent standards. On the other hand, the determination limit of Cd was estimated not reach 0.5 mg L-¹ due to its low SB ratio. In the future, in order to apply it to the on-site analysis of Cd in environmental water, it is necessary to reduce the background intensity by examining the material of the filter and to improve the SB ratio of Cd by more than one order.departmental bulletin pape

Note-Taking recommendations that support academic learning in a User-Led Research by a Student with Developmental Disorder

This study was examined the significance of learning support and the development of this approach to supporting students with developmental disabilities at universities from a user -led research. A graduate study was cited in which a student with developmental disability described in detail her own learning difficulties and coping strategies from her previous elementary and middle, high school experience. Based on her experiences, the student has found five new ways to take notes in different situations to help her deal with college classes and assignments. These results indicate that the user-red research by the student with disabilities can be used to support learning in the primary and secondary education, facilitates their own self-understanding and expression of their intentions.departmental bulletin pape