Selected Articles
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A multi-module deep learning framework with graph-based network and crack attention for tunnel lining crack segmentation from LiDAR point cloud
Cracks in railway tunnels threaten safety and require efficient monitoring. This study introduces PointCrackNet, a deep learning method that detects tunnel lining cracks directly from LiDAR point clouds. By combining graph-based convolution, attention mechanisms, and a crack-enhancement module, the model accurately captures fine crack details while maintaining global structural context. A tailored loss function addresses class imbalance and improves crack continuity. Tested on a large-scale LiDAR dataset from a real railway tunnel, PointCrackNet outperformed existing methods. The approach enables automated tunnel inspection and supports smart, data-driven infrastructure maintenance.
Shanpeng Liu, Koichi Isobe, Junling Si, Diyuan Li, and Daoju Ren
Construction and Building Materials Volume 494, 2025, 143383
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Effects of Combined Deterioration of Steel Corrosion and Freeze-thaw Cycles on the Pull-out Behavior of Deformed Bars in Concrete
This study is the first to systematically investigate how loading sequence and cracking history affect the bond performance of deformed bars under the combined deterioration caused by steel corrosion and freeze–thaw action, a serious problem in concrete structures in cold regions. Through controlled experiments simulating realistic deterioration paths, the study clarified the influence of damage sequence on structural performance. In particular, it demonstrated that pre-existing cracks significantly accelerate deterioration by promoting moisture ingress and freeze–thaw damage. These findings highlight that considering damage history is essential for reliable durability assessment and long-term maintenance planning of aging reinforced concrete infrastructure.
Muhmudul Hasan Mizan, Ryuhei Hayakawa, and Koji Matsumoto
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Superfluid dripping: a new analog for continuous time crystals
The dripping behavior of superfluid helium-4 has been found to be consistently discretized, even when flow rates vary. This unexpected phenomenon suggests that the superfluid dripping system exhibits time crystallinity by spontaneously breaking continuous time translation symmetry. The condition for the emergence of this continuous time crystal is that the edges of the pendant droplets, which hang from the underside of the cup, can move freely—a characteristic specific to superfluid dripping. This free motion leads to volume-independent oscillation periods for the droplets, effectively eliminating the influence of fluctuations in the flow rates.
Shota Takamatsu, Ryota Yamane, Tomoyuki Tani, Yuri Ishimoto, Keito Miyake, Yuki Aoki, and Ryuji Nomura
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Mesoscale modeling of anisotropic compressive behavior and pull-out performance of 3D printed concrete with steel bars using 3D RBSM
This study uses a 3D Rigid Body Spring Model (RBSM) to analyze the anisotropic behavior of 3D-printed concrete (3DPC) with steel reinforcement. Validated by experiments, the research highlights how the mesoscale structure—specifically porous interlayer interfaces—affects performance. Results indicate that specimens loaded parallel to the printing direction exhibit superior compressive strength and bond performance. Conversely, loading perpendicular to the layers leads to stress concentrations and weaker bonds due to interfacial zones. Overall, this research provides a predictive framework for optimizing the structural integrity of 3DPC through mesoscale modeling.
Jiaxu Yao, Jie Luo, Minghong Qiu, and Kohei Nagai
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Substituent Effects on Electrocyclic Reactions: Ultrafast Ring-Opening of α-Phellandrene Stimulated by Impulsively Excited Molecular Vibrations
Zhiyi Zhou, Kenichiro Saita, Yusuke Minegishi, Tetsuya Taketsugu, and Taro Sekikawa*
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Broadband Phase Retardation with Palladium Coated Mirrors for M-edge XMCD in the 40–70 eV Range
Furkan Aksay, and Taro Sekikawa
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Reliable pathfinding problems for a correlated network: A linear programming problem in a hypergraph
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Self-organized luminous pattern formation observed above the anode surface of a DC glow discharge in pure He
To elucidate the mechanism of self-organization phenomena in luminescence observed on the anode surface during atmospheric pressure direct current glow discharge generation, we investigated luminescence patterns while varying pressure in a pure He environment. The results revealed that luminescence patterns appear when the product of pressure p and electrode distance d (pd) is high. Moving forward, we will connect this to reaction-diffusion systems, a method used in mathematics to obtain self-organization phenomena.
Toshiaki Miyazaki, Jan Kuhfeld, Koichi Sasaki, and Naoki Shirai
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SH wave scattering in Eringen’s nonlocal elastic solid using the method of fundamental solutions
Eringen’s nonlocal elastic solid is a mechanical model that enables the analysis of phenomena difficult to describe using classical elasticity. This study analyzed wave scattering in nonlocal elastic solids using the method of fundamental solutions, a meshfree numerical method. An analytical representation of the traction operator specific to nonlocal elasticity was derived, and scattering characteristics relevant to ultrasonic nondestructive testing were evaluated.
Akira Furukawa, Taizo Maruyama, Takahiro Saitoh, Sohichi Hirose, Davinder Kumar, Dilbag Singh, and Sushil K. Tomar
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Protium enrichment by polymer electrolyte fuel cell with hydrogen gas circulation
A polymer electrolyte fuel cell (PEFC) equipped with a gas recirculation system was employed for deuterium separation. Incorporating a hydrogen gas tank into the gas recirculation line achieved significant hydrogen concentration. During fuel cell operation, hydrogen concentration in the gas increased, yielding a high separation factor. This improvement in separation efficiency is thought to result from enhanced separation efficiency via gas-phase chemical exchange reactions.
Toranosuke Nago, Mikito Ueda, and Hisayoshi Matsushima