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991.
俄罗斯商用压水堆VVER和大多数实验堆均采用了六角形紧凑型栅格布置,为了实现VVER和六角形实验堆的高保真数值模拟分析,本文基于数值反应堆物理计算程序（NECP-X）开展了六角形堆芯高保真计算方法研究和程序开发。首先,将全局-局部耦合共振自屏计算方法拓展至六角形堆芯,实现六角形堆芯燃料棒的全堆芯高精度共振计算;其次,基于2D/1D耦合输运计算方法研究了六角形堆芯的高保真计算方法;最后,为了提高全堆芯计算的计算效率,研究了基于区域分解松耦合的非结构网格的粗网有限差分（CMFD）加速方法,可以实现以矩形、六角形和其他多边形栅元为基础的pin-by-pin CMFD 加速。为了验证六角形堆芯高保真计算方法的精度和效率,计算了六角形C5G7基准问题,并分析了六角形输运计算方法的计算精度和CMFD方法的加速效果;将NECP-X程序应用于西安脉冲堆的2D全堆芯计算,与蒙特卡罗程序的结果对比表明NECP-X程序计算得到的特征值和功率分布均具有较高精度。因此,本文建立的六角形堆芯高保真计算方法可以应用于六角形堆芯的分析计算。 相似文献
992.
Tatsuya Funai Megumi Aotani Risa Kiriu Junko Nakamura Yuki Miyazaki Dr. Osamu Nakagawa Dr. Shun-ichi Wada Prof. Dr. Hidetaka Torigoe Prof. Dr. Akira Ono Prof. Dr. Hidehito Urata 《Chembiochem : a European journal of chemical biology》2020,21(4):517-522
Spectroscopic characterization of AgI-ion-mediated C-AgI-A and C-AgI-T base pairs found in primer extension reactions catalyzed by DNA polymerases was conducted. UV melting experiments revealed that C-A and C-T mismatched base pairs in oligodeoxynucleotide duplexes are specifically stabilized by AgI ions in 1:1 stoichiometry in the same manner as a C-C mismatched base pair. Although the stability of the mismatched base pairs in the absence of AgI ions is in the order C-A≈C-T>C-C, the stabilizing effect of AgI ions follows the order C-C>C-A≈C-T. However, the comparative susceptibility of dNTPs to AgI-mediated enzymatic incorporation into the site opposite templating C is dATP>dTTP≫dCTP, as reported. The net charge, as well as the size and/or shape complementarity of the metal-mediated base pairs, or the stabilities of mismatched base pairs in the absence of metal ions, would be more important than the stability of the metallo-base pairs in the replicating reaction catalyzed by DNA polymerases. 相似文献
993.
Ryoichi Chiba Tamon Nakamura Mitsutoshi Kuroda 《Journal of Materials Processing Technology》2011,211(11):1878-1887
In this study, the possibility of solid-state recycling of aluminium alloy machining swarf using cold extrusion and a subsequent cold rolling process is investigated. Cast Al-Si alloy swarf was cold compacted into billets and successfully profile-extruded into square bars with a rectangular cross-sectional aspect ratio of 1:1.8 under an extrusion ratio of 4 or more. After annealing, the extruded bars underwent multi-pass cold rolling into 1-mm thick strips with a total rolling reduction of 85%. Optical microscopy demonstrated that in material recycled using only an extrusion process, coarse residual voids existed in regions where insufficient plastic strain was introduced, causing a visible expansion of the material during heat treatment. However, uniaxial tensile tests showed that extrusion-recycled material had a higher mechanical strength than the original aluminium alloy, implying sufficient bonding among the individual pieces of machining swarf. It was also found that the strength and density of material recycled through extrusion and an additional rolling process were superior to material recycled using extrusion only. Moreover, it was observed that the ductility of the recycled materials was inferior to that of the original aluminium alloy. 相似文献
994.
Tetsushi Ono Tsutomu Kawamura Ryosuke Nakamura 《IEEJ Transactions on Electrical and Electronic Engineering》2021,16(10):1319-1327
More and more factories and commercial buildings are installing combined heat and power (CHP) systems that include various energy storage devices. To reduce the energy cost of CHPs, optimal operation plans to satisfy time-varying energy demands with minimum energy cost are required. Conventional operation planning methods using optimized calculation have an issue with long computing time. To address this, we adapted a convolutional neural network (CNN) to learn the time-series features of input–output pairs of optimized calculations. The architecture of the proposed CNN has the following key features: (i) the application of one-dimensional convolutional filters to extract the time-series features of input data and (ii) the elimination of pooling layers that compress the input data. We also designed rule-based flows to remove constraint violations from the generated operation plans. Our evaluations showed that the proposed method could generate operation plans with the average error of 3.3%, which is much lower than the 8.0% average error when using the conventional CNN with pooling calculation. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. 相似文献
995.
Shigeru Katayama Rio Yamazaki Hikaru Umise Hsu Pei Han Toshihiro Mihara Kimiko Uchiyama Hajime Takahashi Soichiro Nakamura 《Molecular nutrition & food research》2023,67(16):2200212
Scope
Ultraviolet B (UVB) radiation causes skin barrier dysfunction, leading to decreased water-holding capacity, impaired epidermal barrier function, and increased skin thickness. This study investigates the protective effects of oral administration of Lacticaseibacillus paracasei K71 against skin barrier dysfunction in UVB-irradiated mice.Methods and results
Mice are fed diets with or without K71 and irradiated with UVB three times a week for 12 weeks. Oral administration of K71 suppresses UVB-induced decrease in stratum corneum water content, mitigates the increase of transepidermal water loss, and decreases epidermal thickness of the dorsal skin. Treatment with K71 reverses the upregulation of inflammatory cytokines and the activation of nuclear factor-κB induced by UVB irradiation and upregulates the expression of anti-inflammatory IL-10 in the dorsal skin. Notable upregulation of IL-10 is observed in the spleens of K71-treated mice. K71 treatment enhances IL-10 production in J774.1 macrophages; however, this enhancement is diminished by inhibiting K71 phagocytosis and TLR3. Furthermore, transfection using K71 RNAs significantly increases IL-10 production.Conclusion
These results indicate that K71 may alleviate UVB-induced skin barrier dysfunction by attenuating inflammation via increasing IL-10 production and that K71 RNAs may induce IL-10 production in macrophages. Therefore, K71 may be beneficial for preventing skin barrier dysfunction. 相似文献996.
Rayleigh damping is commonly used in response history analysis (RHA) to provide an energy dissipation source, but the adaptation may be difficult if frequency independence damping is desired over a wide frequency range. And, while modal damping produces constant frequency-independent damping, the damping matrix becomes dense, increasing the calculation weight is large. This study examines the advantage of using extended Rayleigh damping in the RHA. First, the multi spring-mass system is used to assess the basic damping performance of the extended Rayleigh damping in the assumed frequency range. A 12-story 3D elastic moment frame model is then used to compare the damping performance. As a result, extended Rayleigh damping is demonstrated to be frequency independent over a wider frequency range than Rayleigh damping and less computationally demanding than modal damping. 相似文献
997.
Junji Akimoto Tadayoshi Akao Kunimitsu Kataoka 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(40):2301617
Garnet-type Li7La3Zr2O12 (LLZ) materials are attracting attention as solid electrolytes (SEs) in oxide-based all-solid-state batteries (ASSBs) owing to their high ionic conductivity. Although the electrochemical stability of LLZ against Li metal is demonstrated with possible high energy density, high-temperature sintering above 1000 °C, which is required to achieve high Li-ion conductivity, results in the formation of insulating impurities at the electrode–electrolyte interfaces. Here, nanosized fine-particle samples of Ta-substituted Li6.5La3Zr1.5Ta0.5O12 (LLZT) are successfully prepared at a remarkably low temperature of 400 °C utilizing an amorphous precursor oxide. The dense LLZT SE sintered by hot pressing at 500 °C shows room-temperature Li-ion conductivity of 1.03 × 10−4 S cm−1 without any additives. In addition, the bulk-type NCM–graphite full battery cell fabricated with the LLZT fine particles through a hot-pressing sintering method at 550 °C exhibits a good charge–discharge performance at room temperature with the bulk-type areal discharge capacity of 0.831 mAh cm−2. The nanosized garnet SE strategy demonstrated in this study paves the way for the formation of oxide-based ASSBs by low-temperature sintering. 相似文献
998.
This paper proposes a new state transfer method for geographic state machine replication (SMR) that dynamically allocates the state to be transferred among replicas according to changes in communication bandwidths. SMR improves fault tolerance by replicating a service to multiple replicas. When a replica is newly added or recovered from a failure, the other replicas transfer the current state of the service to it. However, in geographic SMR, the communication bandwidths of replicas are different and constantly changing. Therefore, existing state transfer methods cannot fully utilize the available bandwidth, and their state transfer time increases. To overcome this problem, our method divides the state into multiple chunks and assigns them to replicas based on each replica's bandwidth so that the broader a replica's bandwidth is, the more chunks it transfers. The proposed method also updates the chunk assignment of each replica dynamically based on the currently estimated bandwidth. The performance evaluation on Amazon EC2 shows that the proposed method reduces the state transfer time by up to 47% compared to the existing one. In addition, we apply the proposed method to dynamic replacement of replicas, which can mitigate latency degradation caused by network trouble, and evaluate how fast the method can relocate a replica. 相似文献
999.
Nakamura Keita Hanari Toshihide Kawabata Kuniaki Baba Keita 《Artificial Life and Robotics》2023,28(2):352-360
Artificial Life and Robotics - Photogrammetry is a three-dimensional (3D) reconstruction from images. In photogrammetry, when each image captures the features of the target object for 3D... 相似文献
1000.