Article
Optics
Louis Alliot de Borggraef, Hugues Guillet de Chatellus
Summary: We have developed a novel architecture that enables distributed acoustic sensing in a commercial single-mode fiber. The system has a sub-cm spatial resolution and an interrogation rate of 20 kHz. The architecture utilizes broadband light waveforms, coherent detection, and all-optical pulse compression to achieve high performance in distributed acoustic sensing applications.
Article
Engineering, Multidisciplinary
Chih-Chung Chung, Wei-Feng Chien, Van-Nhiem Tran, Hong-Ting Tang, Zih-Yi Li, Muhammad Saqlain
Summary: Recognizing land subsidence is vital in complex alluvial-basin aquifers, and this study used TDR technology for automatic and high-accuracy measurements. A physical model was used to examine measurement accuracy and standard deviation in different aquifer scenarios. The study also proposed a novel TDR multi-sections schema to extend the measurement range and reduce signal attenuation.
Article
Environmental Sciences
Chih-Chung Chung, Yen-Kai Wang
Summary: A novel real-time SSC monitoring approach using time domain reflectometry (TDR) was proposed in this study. By improving the method and solving practical problems, the measurement stability and accuracy for long-term monitoring in rivers and reservoirs were enhanced. Experimental results showed that the new method has potential for characterizing suspended sediment load more effectively.
WATER RESOURCES RESEARCH
(2022)
Article
Biology
Kahori Furuhata, Haruchika Masuda, Atsuko Sato, Kumiko Miyata, Naoki Shinyashiki, Rio Kita, Kotaro Imagawa, Tadashi Akamatsu, Shin Yagihara
Summary: This study examined the in vivo water structure dynamics (WSD) between physiological and pathophysiological statuses. The results showed that tumor-bearing mice exhibited aberrant WSD compared to healthy mice. Dielectric spectroscopy may provide novel pathophysiological perspectives in tumor-bearing living bodies.
Article
Engineering, Multidisciplinary
Kai Wang, Chih-Ping Lin
Summary: A real-time and durable system is needed for scour process monitoring in bridge safety management. The study proposed an innovative bundled time domain reflectometry sensing cable to enhance scour monitoring, but issues related to hydrological conditions, long-distance measurement, and actual field implementation still need further investigation. Through numerical simulations and laboratory experiments, a guideline for waveform classification and interpretation was proposed to validly determine scour depth under various field conditions.
STRUCTURAL HEALTH MONITORING-AN INTERNATIONAL JOURNAL
(2021)
Article
Optics
Haijun He, Lin Jiang, Yan Pan, Anlin Yi, Xihua Zou, Wei Pan, Alan E. Willner, Xinyu Fan, Zuyuan He, Lianshan Yan
Summary: The integration of high-speed optical communication and distributed sensing in fibre networks brings intelligent functionalities and improves transmission performance. This work demonstrates an integrated scheme using the same wavelength channel for data transmission and distributed vibration sensing, achieving improved performance and larger launching power. Experimental results show high resolution and frequency response in vibration sensing, offering a new path for exploring the potential of fibre-optic networks and measuring non-linear parameters in coherent optical communications.
LIGHT-SCIENCE & APPLICATIONS
(2023)
Article
Engineering, Multidisciplinary
Yu-Xin Gao, Hong-Hu Zhu, Chao Wei, Jing Wang, Wei Zhang
Summary: Ground collapse events can cause significant economic losses, catastrophic injuries, and fatalities. The use of fiber optic (FO) cables and monitoring techniques like optical frequency domain reflectometry (OFDR) and particle image velocimetry (PIV) can effectively locate and predict ground collapses. The study shows that FO cables can accurately measure strain profiles and settlements under different soil failure mechanisms, and the use of micro-anchors can enhance cable-soil interface bonding.
Article
Instruments & Instrumentation
Morgan L. Funderburk, Jamie Tran, Michael D. Todd, Anton Netchaev, Kenneth J. Loh
Summary: Local scour is becoming a major cause of bridge failure worldwide, with the effects of climate change increasing the vulnerability of bridges. This study explores the use of ultrasonic time-domain reflectometry for continuous monitoring of soil interface in order to detect scour. The results show that the Lamb wave scour sensor is capable of reliably detecting soil interfaces at regular intervals.
SMART MATERIALS AND STRUCTURES
(2022)
Article
Engineering, Electrical & Electronic
Evan Benoit, Joel B. Harley, Cynthia M. Furse
Summary: We evaluate the feasibility of spectral time domain reflectometry (STDR) and spread spectrum time domain reflectometry (SSTDR) as a new modality for impedance measurement. The study focuses on testing energized/noisy systems over a broad frequency spectrum and multiple channels in parallel. Signal parameters of S/SSTDR and their effects on accuracy and usable frequency band are simulated, along with an initial measurement validation. The conclusion includes a recommendation for a viable multichannel impedance measurement system for energized or nonenergized systems in noisy environments.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2023)
Article
Optics
Miguel Soriano-Amat, Hugo F. Martins, Vicente Duran, Luis Costa, Sonia Martin-Lopez, Miguel Gonzalez-Herraez, Maria R. Fernandez-Ruiz
Summary: The phase-sensitive optical time-domain reflectometry (phi OTDR) technique provides spatio-temporal measurements of environmental variables in real time, with a novel approach achieving cm-scale spatial resolutions over 1 km at remarkably low detection bandwidths. This approach utilizes dual-comb spectrometry and random phase-spectral coding to maximize signal-to-noise ratio for sensing schemes.
LIGHT-SCIENCE & APPLICATIONS
(2021)
Article
Chemistry, Analytical
Andres Biondi, Rui Wu, Lidan Cao, Balaji Gopalan, Jackson Ivey, Camila Garces, Michael Mitchell, John D. D. Williams, Xingwei Wang
Summary: This paper introduces a distributed fiber optic smart textile (DFOST) embedded into a composite panel for optimizing the performance and durability of composite materials. DFOST is created using an embroidery method, allowing for different layout patterns and enabling two- or three-dimensional measurements. Measurements of strain, temperature, and displacement changes are obtained using optical frequency domain reflectometry (OFDR).
Article
Engineering, Electrical & Electronic
Hyeong Min Lee, Geon Seok Lee, Gu-Young Kwon, Su Sik Bang, Yong-June Shin
Summary: The demand for cable diagnostics and monitoring techniques has increased significantly in recent decades. Among various diagnostic tests, reflectometry stands out as a nondestructive method that can be applied regardless of cable type. Time-frequency domain reflectometry, an improved type, is more accurate than conventional methods and robust to noise, making it suitable for industrial applications.
IEEE SENSORS JOURNAL
(2021)
Article
Engineering, Electrical & Electronic
Zhenyu Xu, Thomas Mauldin, Zheyi Yao, Gerald Hefferman, Tao Wei
Summary: Time-domain reflectometry (TDR) is an established method for measuring impedance inhomogeneity of waveguides, but traditional TDR systems are costly and bulky, limiting their practicality. There is a growing demand for a simple, portable, and low-cost TDR technology to address this issue.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2021)
Article
Engineering, Electrical & Electronic
Andrea Cataldo, Egidio De Benedetto, Raissa Schiavoni, Giuseppina Monti, Annarita Tedesco, Antonio Masciullo, Emanuele Piuzzi, Luciano Tarricone
Summary: This article introduces an innovative wearable device that monitors skin hydration through microwave reflectometry technique. The device has good wearability and surface adherence to the skin. The potential of the system is validated through numerical analysis and experimental tests.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2022)
Article
Optics
Andrea Baggio, Matteo Turani, Massimo Olivero, Milena Salvo, Diego Pugliese, Marco Sangermano
Summary: A new system is developed to detect hydrocarbons using optical fiber distributed sensing. The system utilizes a custom-designed optical fiber with silica core and thin silicone cladding, providing quick and selective absorption of oil products and insensitivity to water. By detecting Rayleigh backscattering, the system demonstrates a rapid response to high refractive index hydrocarbons, with a response time of approximately 1 s. Furthermore, in its high-resolution version, the system can accurately locate leakages with an accuracy of 14 cm.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Materials Science, Composites
Yusuke Nishio, Akira Todoroki, Yoshihiro Mizutani, Yoshiro Suzuki
ADVANCED COMPOSITE MATERIALS
(2017)
Article
Engineering, Electrical & Electronic
Masahiro Suzuki, Yoshiro Suzuki, Akira Todoroki, Yoshihiro Mizutani
IEEE SENSORS JOURNAL
(2018)
Article
Chemistry, Multidisciplinary
Vannei Sry, Yoshihiro Mizutani, Gen Endo, Yoshiro Suzuki, Akira Todoroki
APPLIED SCIENCES-BASEL
(2018)
Article
Materials Science, Composites
Kouki Ishii, Akira Todoroki, Yoshihiro Mizutani, Yoshiro Suzuki, Yoichiro Koga, Ryosuke Matsuzaki, Masahito Ueda, Yoshiyasu Hirano
ADVANCED COMPOSITE MATERIALS
(2019)
Article
Materials Science, Composites
Akira Todoroki, Tastuki Oasada, Yoshihiro Mizutani, Yoshiro Suzuki, Masahito Ueda, Ryosuke Matsuzaki, Yoshiyasu Hirano
ADVANCED COMPOSITE MATERIALS
(2020)
Article
Mechanics
Takeshi Ashizawa, Yoshihiro Mizutani, Nobuyuki Toyama, Akira Todoroki, Yoshiro Suzuki
COMPOSITE STRUCTURES
(2020)
Article
Materials Science, Textiles
V Sry, D. Y. Jung, Y. Mizutani, G. Endo, A. Todoroki
Summary: This study investigates the effect of preload treatment on the elastic modulus of braided high modulus polyethylene (HMPE) rope for static loading in tendon-driven robot. It is found that preloading in tensile loading can be an alternative method to replace the commonly used preload treatment in cyclic loading. After preload treatment, the elastic modulus of the preloaded rope and strand at the first cycle is the smallest, attributed to the elastic recovery of the material itself.
JOURNAL OF THE TEXTILE INSTITUTE
(2021)
Article
Materials Science, Composites
Takeshi Ashizawa, Yoshihiro Mizutani, Nobuyuki Toyama, Akira Todoroki, Daniel Lopez Rodrigo
Summary: This study examined the three-dimensional propagation of bulk waves in CFRPs with concentrically curved fibers, expanding the similarity law to account for the 3D propagation behaviors. The experimental visualization demonstrated that the shape changes of quasi-longitudinal waves follow the similarity law, eventually verifying it for 3D propagation. Mathematical discussion based on the governing equations showed the need for equal expansion parameters in both thickness and radial directions to satisfy the similarity law in the 3D case.
ADVANCED COMPOSITE MATERIALS
(2021)
Article
Materials Science, Textiles
Doyun Jung, Yoshihiro Mizutani, Akira Todoroki, Wonjin Na
Summary: Exposure to up to 300 hours of ultraviolet irradiation led to a decrease in tensile strength and higher attenuation of acoustic emission signals in glass fiber-reinforced composite specimens. While the b-value initially tended to increase with exposure to UV light, it decreased after 300 hours, highlighting the impact of attenuation on the structural health parameter calculation.
FIBERS AND POLYMERS
(2021)
Article
Materials Science, Textiles
Vannei Sry, Yoshihiro Mizutani, Gen Endo, Akira Todoroki
Summary: This article discusses the stabilization of longitudinal elastic modulus of braided high modulus polyethylene rope for dynamic loading in tendon-driven robot through preload treatment. Utilizing experimental data and a spring-dashpot model, the strain of the rope under impact loading can be estimated with consistent results.
JOURNAL OF THE TEXTILE INSTITUTE
(2022)
Article
Materials Science, Composites
Wataru Matsunaga, Koichi Mizukami, Yoshihiro Mizutani, Akira Todoroki
Summary: A novel eddy current testing method was developed for testing UD-CFRP and controlling the detection range. By adding electrodes orthogonal to the fibers, the eddy current density could be significantly increased, and the depth distribution of the eddy current density could be controlled by adjusting the distance of the electrodes. However, for quasi-isotropic CFRP, the distance of the electrodes could not control the depth distribution of the eddy current density. The impedance of the UD-CFRP with electrodes increased as the distance between electrodes increased, which was consistent with the numerical simulation results.
ADVANCED COMPOSITE MATERIALS
(2022)
Article
Materials Science, Composites
Xiaojuan Xu, Wataru Matsunaga, Koichi Mizukami, Yoshihiro Mizutani, Akira Todoroki
Summary: This study proposes a smart eddy current testing method for identifying crack orientation by introducing an additional electrically anisotropic plate. The experimental results show that the magnetic field distribution changes when the anisotropic plate is inserted, and the output voltage of the probe is affected by the angle between the conductivity angle of the anisotropic plate and the crack orientation.
ADVANCED COMPOSITE MATERIALS
(2023)
Article
Materials Science, Composites
Wataru Matsunaga, Yoshihiro Mizutani
Summary: This study investigates the arrangement and shape of coils for permittivity measurement using electromagnetic induction testing (EIT) in a dielectric sandwiched between carbon fiber reinforced plastics (CFRPs). Finite element analysis (FEA) confirms that EIT can be used for permittivity measurement. Suitable coil arrangement and shape are determined through FEA analysis. The experimental results demonstrate the effectiveness of the proposed method for permittivity measurement.
ADVANCED COMPOSITE MATERIALS
(2023)
Article
Engineering, Chemical
Rio Hirakawa, Tetsuo Yasuoka, Yoshihiro Mizutani
Summary: The effect of a rectangular convex/concave shape on preventing crack growth in adhesively bonded joints was investigated analytically. The study used the finite element method to simulate a double cantilever beam test and evaluate crack growth resistance. The results showed that both concave and convex shapes improved fracture toughness and acted as crack arresters.
JOURNAL OF ADHESION
(2023)
Article
Materials Science, Composites
Wataru Matsunaga, Koichi Mizukami, Yoshihiro Mizutani, Akira Todoroki
Summary: In this study, a novel method using electromagnetic induction testing was presented to estimate the moisture absorption rate of glass fiber reinforced plastics. The relationship between permittivity and moisture absorption rate was analytically calculated, and the validity of the method was verified through experiments.
COMPOSITES PART C: OPEN ACCESS
(2022)
Article
Mechanics
Rawan Aqel, Patrick Severson, Rani Elhajjar
Summary: A novel core splice joint configuration for composite sandwich structures is studied and proposed to improve the strength and toughness. Experimental and numerical efforts show that this configuration can significantly increase the ultimate strength by 13% to 51% and the toughness by 2% to 35%.
COMPOSITE STRUCTURES
(2024)
Article
Mechanics
Xianheng Wang, Cong Chen, Jinsong Zhang, Xinming Qiu
Summary: In this paper, a new form-finding method based on spatial elastica model (FMSE) is proposed for elastic gridshells. The method integrates the deformations of elastic rods into the overall deformation of the gridshell, and solves a set of transcendental equations using the quasi-Newton method to ensure the deformation satisfies the given boundary conditions. The method is validated through experiments and expected to have potential applications in the investigations of elastic gridshells.
COMPOSITE STRUCTURES
(2024)
Article
Mechanics
Hao Huang, Zitong Guo, Zhongde Shan, Zheng Sun, Jianhua Liu, Dong Wang, Wang Wang, Jiale Liu, Chenchen Tan
Summary: The conventional evaluation of 3D braided composites' mechanical properties through numerical and experimental methodologies hinders material application due to the expenses, time constraints, and laborious efforts involved. This study establishes a multi-scale finite element model and a surrogate model for predicting the elastic properties of 3D4D rotary braided composites with voids. By optimizing a neural network model, the results are validated and provide valuable insights into the microstructure and properties of these composites.
COMPOSITE STRUCTURES
(2024)
Article
Mechanics
Xinyu Li, Hao Zhang, Haiyang Yang, Junrong Luo, Zhongmin Xiao, Hongshuai Lei
Summary: Due to their excellent mechanical properties and design flexibility, fluted-core composite sandwich structures have gained significant attention in aerospace and rail transit applications. This study investigated the free-vibration characteristics and optimized design of composite fluted-core sandwich cylinders through theoretical models and experimental tests.
COMPOSITE STRUCTURES
(2024)
Article
Mechanics
Chao Li, Chunzheng Duan, Xiaodong Tian, Chao Wang
Summary: A mechanistic model considering the bottom edge cutting effect and the anisotropic characteristics of the material is proposed in this paper to accurately predict cutting forces. The model was validated through a series of milling experiments and can be used to predict the cutting force of various parts of the cutter and any feed direction.
COMPOSITE STRUCTURES
(2024)
Article
Mechanics
Camila Sanches Schimidt, Leopoldo Pisanelli Rodrigues de Oliveira, Carlos De Marqui Jr
Summary: This work investigates the vibro-acoustic performance of graded piezoelectric metamaterial plates. The study shows that piezoelectric metamaterial plates with reconfigurable properties can provide enhanced vibration and sound power attenuation.
COMPOSITE STRUCTURES
(2024)
Article
Mechanics
Jun Ke, Li-jie Liu, Zhen-yu Wu, Zhong-ping Le, Luo Bao, Dong-wei Luo
Summary: Compared with other green natural fibers, ramie has higher mechanical properties and lower cost. In this study, ramie and glass fiber are made into composite circular tubes. The results show that the hybrid circular tube with ramie and glass fiber has improved torsional mechanical properties and reduced weight and cost. The failure mechanisms are affected by the loading direction and the content of each fiber.
COMPOSITE STRUCTURES
(2024)
Article
Mechanics
Natalia Pingaro, Gabriele Milani
Summary: This paper proposes an enhanced analytical model for predicting the behavior of FRCM samples tested under standard tensile tests. The model takes into account the interaction between fibers and matrix through the interface, and assumes different material properties at different phases. By solving a second order linear differential equation, an analytical solution can be obtained. The model is validated with experimental data and shows good predictability.
COMPOSITE STRUCTURES
(2024)
Article
Mechanics
Jialiang Fan, Anastasios P. Vassilopoulos, Veronique Michaud
Summary: This article investigates the effects of voids, joint geometry, and test conditions on the fracture performance of thick adhesive Double Cantilever Beam (DCB) joints. It concludes that grooved DCB joints with low void content tested at low displacement rates showed stable crack propagation without significant crack path deviation.
COMPOSITE STRUCTURES
(2024)
Article
Mechanics
Auwalu I. Mohammed, Kaarthikeyan Raghupathy, Osvaldo De Victoria Garcia Baltazar, Lawson Onokpasah, Roger Carvalho, Anders Mogensen, Farzaneh Hassani, James Njuguna
Summary: This study investigates the performance of composite pressure vessels under damaged and undamaged conditions, providing insights into their reliability and residual strength capabilities. The results demonstrate that the damage profile and its effect on compressive strength are similar between damaged and non-damaged cylinders. When subjected to quasi-static compression, the polyethylene liner absorbs enough elastic strain energy to recover without plastic deformation. Additionally, quasi-static compression has little to no influence on the axial strength of the cylinders. The damage characterization reveals fiber breakage, delamination, local buckling, and brooming failure. This study has direct implications for the safety design tolerances, manufacturing strategies, and operational failure conditions of composite overwrapped pressure vessels (COPVs).
COMPOSITE STRUCTURES
(2024)
Article
Mechanics
Muhammad Irfan Shirazi, Samir Khatir, Djilali Boutchicha, Magd Abdel Wahab
Summary: Structural health monitoring is important to ensure the safety of components and structures. This study proposes a method using finite element models and 1D-CNN network to extract and classify vibration responses for crack detection. The results show that the proposed approach is effective in real-time damage detection.
COMPOSITE STRUCTURES
(2024)
Article
Mechanics
Maryam Mirsalehi, Kiarash Kianpour, Sharif Shahbeyk, Mohammad Bakhshi
Summary: This study comprehensively investigates the one-way response of 3D-woven sandwich panels (3DWSPs) and their interfering parameters, providing interpretation of elastic and failure results, failure maps, and reliable theoretical models for linear elastic response and observed failure mechanisms.
COMPOSITE STRUCTURES
(2024)
Article
Mechanics
Yiming Zhao, Zhonggang Wang, Zhigang Yang, Bin Qin
Summary: The paper proposes a Ritz and statistical energy analysis (Ritz SEA) hybrid method for calculating rectangular plate acoustic vibration coupling in the mid-frequency range. This method combines the fast convergence and ability to handle arbitrary boundary conditions of the Ritz method with the power flow equation of the statistical energy analysis method. The results show that this approach effectively filters out random fluctuations in mid-frequency domains while demonstrating exceptional stability and precision.
COMPOSITE STRUCTURES
(2024)
Article
Mechanics
Joao Henrique Fonseca, Woojung Jang, Dosuck Han, Naksoo Kim, Hyungyil Lee
Summary: This study addresses the enhancement of an injection-molded fiber-reinforced plastic / metal hybrid automotive structure and its plastic injection molding process through the integration of the finite element method, artificial intelligence, and evolutionary search methods. Experimental validation of finite element models, the generation of a database through orthogonal array and Latin hypercube methods, and the training of artificial neural networks are conducted. The genetic optimization algorithm is then applied to identify optimal process parameters. The results show significant reduction in product warpage and manufacturing time while maintaining structural strength, contributing to the advancement of composite automotive structures with superior quality.
COMPOSITE STRUCTURES
(2024)
Article
Mechanics
Alessandro Vescovini, Carina Xiaochen Li, Javier Paz Mendez, Bo Cheng Jin, Andrea Manes, Chiara Bisagni
Summary: This paper presents a study on six single-stringer specimens manufactured using the card-sliding technique with non-crimp fabrics and adopting a Double-Double (DD) stacking sequence. The specimens were tested under compression loading conditions to investigate post-buckling and failure in aerospace structures. Experimental results and numerical simulations were compared to analyze the behavior and failure modes of the specimens. The study found promising evidence of a viable solution to optimize aeronautical structures and enhance resistance to skin-stringer separation, particularly with the use of tapered flanges.
COMPOSITE STRUCTURES
(2024)
