Current Issue : April-June Volume : 2026 Issue Number : 2 Articles : 5 Articles
The transmission tower serves as a critical component of the national power transmission system, and together with overhead transmission lines, constitutes a nationwide power grid. However, as an indispensable part of transmission line infrastructure, it is highly susceptible to extreme structural failures such as overturning and collapse induced by external loads or material corrosion, which severely undermine the operational stability and safety of transmission lines. This paper proposes an innovative construction technique for replacing structural members of high- voltage transmission towers. The proposed method ensures the stability of the local member system during the replacement process and guides the construction under the coupled interaction of the tower- line system. A form- finding analysis of the ground wire is performed, deriving a mathematical model that characterizes the profile of transmission lines under combined self- weight and wind load conditions. By applying the equal- strength replacement principle and numerical simulation methods, the feasibility and practicality of in-situ live- line member replacement are verified. This method enables construction and maintenance work by replacing partial structural members without the need for complete tower dismantlement. Monitoring results indicate that the deformation deviations of the tower in all directions are maintained within the allowable safety range. Compared with conventional methods, this technique facilitates rapid in-situ live- line repair, offering remarkable advantages in terms of construction duration and economic efficiency....
Recognizing the negative consequences of auto-oriented urban transportation, Chinese cities began developing Urban Street Design Guidelines (USDGs) in 2016. The literature on urban transportation design from a decision-making perspective is very limited. As the first systematic evaluation of the pioneering effort by cities in China, this study analyzes local USDG documents and interviews key practitioner stakeholders from ten large cities by adapting a leading policy evaluation tool of urban street design for sustainable transportation based on the Complete Streets Policy Framework. A total of 11 USDGs adopted between 2016 and 2020 were evaluated to represent the wide range of urban contexts in China. The evaluation revealed an average performance of only 30.9% of the total possible score. Despite strong aspirations, local USDGs face significant implementation challenges, lack consideration of disadvantaged communities, and need clarify modal priorities in diverse contexts. Targeted improvements could contribute to more effective and sustainable urban street building and management in China’s cities. As an ex-ante assessment, this study provides a key reference for the future analyses of the outcomes of local USDGs....
Structural health monitoring (SHM) is critical for ensuring the safety and serviceability of civil infrastructures. Traditional vibration-based damage detection methods often rely on manually extracted features and expert knowledge, which can be time-consuming and subjective. This paper proposes a novel, data-driven approach for damage detection in simply supported beam structures utilizing a one-dimensional Convolutional Neural Network (1D-CNN). The proposed method automatically learns discriminative features directly from raw acceleration response signals under ambient excitation, eliminating the need for manual feature engineering. A numerical model of a simply supported beam is established to generate acceleration data for various damage scenarios, including different locations and severity levels of cracks. The collected time-domain signals are used to train and validate the designed 1DCNN model. Experimental results demonstrate that the proposed CNN model achieves high accuracy in identifying the presence, location, and severity of damage. The model exhibits strong robustness to noise and outperforms traditional methods that rely on modal parameters (e.g., natural frequencies and mode shapes). This study confirms the feasibility and effectiveness of using deep learning, specifically 1D-CNN, as a powerful and efficient tool for automated damage diagnosis in beam-like structures, offering significant potential for real-world SHM applications....
This paper details the design of a rectangular patch antenna intended for WLAN wireless communication systems. The antenna operates within a frequency range of 1.5 GHz to 3.5 GHz and is constructed using a wooden substrate with a relative permittivity of 1.77, a loss tangent of 0.0577, and a thickness of 1.6 mm. The antenna’s performance is evaluated through key parameters, including a reflection coefficient (S11) of −43.9987 dB, standing wave ratio (VSWR) of 1.0127, gain of 2.4 dB, directivity of 8.7 dB, efficiency of 23.36%, bandwidth of 180 MHz, and radiation diagram where obtained using ANSYS HFSS software. The results demonstrate that using wood as the substrate provides satisfactory performance for the antenna design....
Gradient stiffness structures are increasingly recognized for their excellent energy absorption capabilities, particularly under challenging loading conditions. Most studies focus on varying the thickness of the structure in order to produce gradient stiffness. This work introduces an innovative approach to design honeycomb architectures with controlled gradient stiffness along the out-of-plane direction achieved by materials’ microstructure variations. The gradient is achieved by combining three types of thermoplastic polyurethane (TPU) materials: porous TPU, plain TPU, and carbon fiber (CF)-reinforced TPU. By varying the material distribution across the honeycomb layers, a smooth transition in stiffness is formed, improving both mechanical resilience and energy dissipation. To fabricate these structures, a dual-head 3D printer was employed with one head printed processed TPU with a chemical blowing agent to produce porous and plain sections, while the other printed a CF-reinforced TPU. By alternating between the two print heads and modifying the processing temperatures, honeycombs with up to three distinct stiffness zones were produced. Compression testing under out-of-plane loading revealed clear plateau and densification regions in the stress–strain curves. Pure CF-reinforced honeycombs absorbed the most energy at stress levels above ~4.5 MPa, while porous TPU honeycombs were more effective under stress levels below ~1 MPa. Importantly, the gradient stiffness honeycombs achieved a balanced energy absorption profile across a broader range of stress levels, offering enhanced performance and adaptability for applications like protective equipment, packaging, and automotive structures....
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