Electrical Insulation Characteristics at Cryogenic Temperature for High Temperature Superconducting Cables

Okubo, Hitoshi,Hayakawa, Naoki The Korean Institute of Electrical Engineers 2004 KIEE International Transactions on Electrophysics Vol.4C No.1

This paper discusses electrical insulation characteristics at cryogenic temperature, especially focusing on partial discharge (PD) inception characteristics, for high temperature superconducting cables. In liquid nitrogen (L$N_2$) / polypropylene (PP) laminated paper composite insulation system, PD inception strength (PDIE) was evaluated in terms of volume effect and V-t characteristics. Different kinds of butt gap condition were applied in the experiments, using parallel plane and coaxial cylindrical cable samples. Experimental results revealed that the volume effect on PDIE could be evaluated by the statistical stressed liquid volume (SSLV) taking account the discharge probability not only in the butt gap but also in the other thin layers between PP laminated papers. Furthermore, the indices n of V-t characteristics at PD inception were estimated to be 80∼110, irrespective of the butt gap condition.

Detection of the $D_0{\rightarrow}D_1$ transition of $\beta$-carotene radical cation photoinduced in photosystem II

Okubo, Tatsunori,Tomo, Tatsuya,Noguchi, Takumi 한국광과학회 2009 Photochemical & photobiological sciences Vol.8 No.2

The $D_0{\rightarrow}D_1$ absorption band of a $\beta$-carotene radical cation in the near-infrared (NIR) region was detected for the first time in photosystem II (PSII). PSII-enriched membranes and isolated reaction center (RC) complexes (D1/D2/$Cytb_{559}$) from spinach were illuminated at 80 and 150 K, respectively, in the presence of electron acceptors. In both preparations, UV-Vis-NIR difference spectra upon illumination exhibited a medium-intensity band at ~1450 nm along with a strong band at ~990 nm. The latter band has been assigned to the $D_0{\rightarrow}D_2$ transition of the radical cation of the $\beta$-carotene in the secondary electron transfer pathway in PSII. These NIR bands disappeared at 210 K in the PSII membranes, and diminished their intensities in the RC complexes partially depleted of carotenoid. The absence or diminish of the $\beta$-carotene cation with little change in the formation of chlorophyll cations under these conditions were also confirmed by detecting light-induced FTIR difference spectra in the mid-IR region. From these results, it was concluded that the NIR band observed at ~1450 nm arose from the $D_0{\rightarrow}D_1$ transition of the $\beta$-carotene radical cation. It was shown that the observed band in the RC complexes was a mixture of the band of one $\beta$-carotene cation (${Car_{507}}^+$) at 1464 nm and that of the other cation (${Car_{489}}^+$) at a wavelength shorter than 1434 nm, indicating that the $D_0{\rightarrow}D_1$ transition is sensitive to the protein environment. It is proposed that the position and the relative intensity of the $D_0{\rightarrow}D_1$ band together with the well-known $D_0{\rightarrow}D_2$ band can be useful monitors to investigate the properties of the radical cation and the molecular interaction of $\beta$-carotene in the PSII proteins.

History and Future Challenges of Sports Promotion Activities in Japan - From the Sports Promotion Act (1961) to the Basic Act on Sports (2011) -

( Okubo Hideak ),( Kanazawa- Seiryo ) 한국체육학회 2016 국제스포츠과학 학술대회 Vol.2016 No.1

The Sports Promotion Act, the first of its kind in Japan, was established in 1961 with an eye toward the Games for the XVIII Olympiad in Tokyo (1964). While it was the only law that laid down Japan’s sports policies, the act did not require the central government or local governments to implement any specific measures or guarantee to finance sports promotion activities. It was characterized by the enumeration of non-binding targets (such as, “efforts should be made to achieve…”). On the other hand, since it was based on amateurism, the act has contributed to the dissemination of sports among schools, companies, and the public. However, it lacked measures to secure financial resources and, therefore, failed to provide effective countermeasures against the termination or discontinuation of more than 300 company sport clubs, which had been taking place due to economic stagnation in the 1990s. Moreover, since the act did not address professional sports to begin with, the act was regarded not instrumental in the professionalization and sophistication of sports or the development of top-level international athletes. In 2011, the Sports Promotion Act was repealed for the first time in 50 years, and the Basic Act on Sports was newly established in response to the campaign to host the Games of the XXXII Olympiad (2020). The new act stipulates that all people have the right to sports and declares that it is the responsibility of the state to promote the public significance of and policies on sports. It lays out eight basic principles of sports, one of which states that athletes, including professional athletes, should strive to perform well in international competitions. In this presentation, I would like to discuss the sport policies that have been promoted for 50 years under the Sports Promotion Act and their characteristics, the sports policies that will be rolled out over the coming several decades under the Basic Act on Sports and their characteristics, and the role that the academic society should play in promoting those policies.

Relative validity of dietary patterns derived from a self-administered diet history questionnaire using factor analysis among Japanese adults

Okubo, Hitomi,Murakami, Kentaro,Sasaki, Satoshi,Kim, Mi Kyung,Hirota, Naoko,Notsu, Akiko,Fukui, Mitsuru,Date, Chigusa Cambridge University Press 2010 Public health nutrition Vol.13 No.7

<B>Abstract</B><B>Objective</B><P>Although dietary pattern approaches derived from dietary assessment questionnaires are widely used, only a few studies in Western countries have reported the validity of this approach. We examined the relative validity of dietary patterns derived from a self-administered diet history questionnaire (DHQ) among Japanese adults.</P><B>Design</B><P>The DHQ, assessing diet during the preceding month, and 4 d dietary records (DR) were collected in each season over one year. To derive dietary patterns, 145 food items in the DHQ and 1259 in the DR were classified into thirty-three predefined food groups, and entered into a factor analysis.</P><B>Setting</B><P>Three areas in Japan; Osaka (urban), Nagano (rural inland) and Tottori (rural coastal).</P><B>Subjects</B><P>A total of ninety-two Japanese women and ninety-two Japanese men aged 31-76 years.</P><B>Results</B><P>We identified three dietary patterns (‘healthy’, ‘Western’ and ‘Japanese traditional’) in women and two (‘healthy’ and ‘Western’) in men, which showed a relatively similar direction and magnitude of factor loadings of food groups across the first and mean of four DHQ (DHQ1 and mDHQ, respectively) and 16 d DR. The Pearson correlation coefficients between DHQ1 and 16 d DR for the healthy, Western and Japanese traditional patterns in women were 0·57, 0·36 and 0·44, and for the healthy and Western patterns in men were 0·62 and 0·56, respectively. When mDHQ was examined, the correlation coefficients improved for women (0·45-0·69).</P><B>Conclusions</B><P>Dietary patterns derived from the DHQ could be used for epidemiological studies as surrogates of those derived from DR.</P>

Three major dietary patterns are all independently related to the risk of obesity among 3760 Japanese women aged 18–20 years

Okubo, H,Sasaki, S,Murakami, K,Kim, M K,Takahashi, Y,Hosoi, Y,Itabashi, M Nature Publishing Group 2008 International Journal of Obesity Vol.32 No.3

Objective:To examine associations between dietary patterns and obesity.Design:Cross-sectional study.Subjects:A total of 3760 Japanese female dietetic course students aged 18–20 years from 53 institutions in Japan.Measurements:Diet was assessed over a 1-month period with a validated self-administered diet history questionnaire with 148 food items, from which 30 food groups were created and entered into a factor analysis. Body mass index (BMI) was calculated from self-reported body height and weight.Results:Mean BMI (±s.d.) was 20.9±2.8 kg m<SUP>−2</SUP>. Four dietary patterns were identified. After adjustment for several confounding factors and total energy intake, the ‘Healthy’ pattern, characterized by high intakes of vegetables, mushrooms, seaweeds, potatoes, fish and shellfish, soy products, processed fish, fruit and salted vegetables, was significantly associated with a lower risk of BMI25 (odds ratio of the highest quintile vs lowest, 0.57; 95% confidence interval: 0.37–0.87; P for trend <0.05). In contrast, the ‘Japanese traditional’ pattern, characterized by high intakes of rice, miso soup and soy products, and the ‘Western’ pattern, characterized by high intakes of meats, fats and oils, seasonings, processed meats and eggs, were both significantly associated with an increased risk of BMI25 (OR: 1.77; 95% CI: 1.17–2.67; P for trend <0.01 and OR: 1.56; 95% CI: 1.01–2.40; P for trend=0.04, respectively).Conclusion:Three major dietary patterns, Healthy, Japanese traditional and Western, were all independently and significantly related to the risk of obesity even among a relatively lean young Japanese female population.International Journal of Obesity (2008) 32, 541–549; doi:10.1038/sj.ijo.0803737; published online 25 September 2007

A VIEW FROM JAPANESE DEVELOPMENT EXPERIENCES

Okubo, Masakazu CONSORTIUM ON DEVELOPMENT STUDIES 1990 DYNAMIC TRANSFORMATION Vol.1990 No.-

錦絵と繪本一浮世絵版画の形態と特質

大久保純一(Okubo Junichi),정해열(번역자) 한국국학진흥원 2005 국학연구 Vol.6 No.-

Binary Document Classification Based on Fast Flux Discriminant with Similarity Measure on Word Set

Keisuke Okubo,Gendo Kumoi,Masayuki Goto 대한산업공학회 2019 Industrial Engineeering & Management Systems Vol.18 No.2

Fast Flux Discriminant (FFD) is known as one of the high-performance nonlinear binary classifiers, and it is possible to construct a classification model considering the interaction between variables. In order to take account of the interaction between variables, FFD introduces the histogram-based kernel smoothing using subspaces including variable combinations. However, when creating a subspace, the original FFD should cover all variables including combinations of variables with low interaction. Therefore, the disadvantage is that the calculation amount increases exponentially as the dimension increases. In this study, we calculate the similarity between variables by using KL divergence. Then, among the obtained similarities, divisions are performed for each subspace with similar variables. Through this method, we try to reduce the amount of calculation while maintaining classification accuracy by using only combinations of variables that are likely to take high interaction. Through the simulation experiments with Japanese newspaper articles, the effectiveness of our proposed method is clarified.

Simultaneous Optimization of Task Allocation and Path Planning Using Mixed-Integer Programming for Time and Capacity Constrained Multi-Agent Pickup and Delivery

Takuma Okubo,Masaki Takahashi 제어로봇시스템학회 2022 제어로봇시스템학회 국제학술대회 논문집 Vol.2022 No.11

Lately, there has been a need to improve the efficiency of material movements within factories and multi-agents are required to perform these tasks. In this study, graphical representation and mixed-integer programming have been adopted for simultaneous optimization of task allocation and path planning for each agent to achieve the following three goals. First, this study realizes time and capacity constrained multi-agent pickup and delivery (TCMAPD) that simultaneously considers time constraints, capacity constraints, and collision avoidance. Previous studies have not considered these constraints simultaneously. Thus, we can solve the problems associated with using multi-agents in actual factories. Second, we achieved TCMAPD that optimizes the collision avoidance between multi-agents. In conventional research, only a single collision avoidance method can be used. However, an appropriate route was selected from a variety of avoidance methods in this study. Hence, we could achieve a more efficient task allocation and path planning with collision avoidance. Third, the proposed method simultaneously optimizes task allocation and path planning for each agent. Previous studies have separately considered the approach of optimizing task allocation and path planning or used the cost of path planning after task allocation to again perform task allocation and path planning. To simultaneously optimize them in a single plan, we have developed a solution-derivable formulation using mixed-integer programming to derive a globally optimal solution. This enables efficient planning with a reduced total time traveled by the agents.

연구발표초록 - 특별강연 ( 유동층 )

Tatsuya Okubo,Hiroyuki Kawamura,Katsuki Kusakabe,Shigeharu Morooka 한국화학공학회 1990 춘계학술발표회 Vol.- No.-