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Uncertainty quantification of the concrete Modulus of Elasticity through different experiment tests and sensors
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Investigation of the Effect of Harmonics Caused by Transformer-Induced Nonlinear Loads on Electrical Energy
Get PDFIn this study, distribution transformers in the Mu¸s Alparslan University campus are analyzed in order to minimize energy losses due to harmonics in the electrical network. Current and voltage harmonics, which are the power quality problems of these transformers, are analyzed. The power quality of different transformers in Mu¸s Alparslan University was measured with a Chauvin Arnoux CA:8331 energy analyzer. Three-phase nonlinear load models were created using current harmonic values in the Matlab/Simulink environment. A parallel active power filter is designed in the Matlab/Simulink environment to eliminate current harmonics. The performance of the parallel active power filter is analyzed for each transformer. As a result, the total harmonic distortion (THDI) ratio for the current decreased from 6.78% to 1.38% in fast Fourier transform analyses after the parallel active power filter was activated in the first transformer. Similarly, the THDI ratio decreased from 5.1% to 2.19% in the second transformer, from 4.5% to 1.39% in the third transformer, and from 5.63% to 1.36% in the fourth transformer.OPEN ACCESS Received: 20/02/2025 Accepted: 15/04/2025 Published: 30/05/202
Vectorization for Tower Sketches Using Large Model and Deep Learning
Get PDFBackground:3D modeling of transmission towers from hand-drawn sketches is occasionally needed in the exploration stage, construction stage, or operation of transmission lines. To achieve automatic 3D modeling, extracting standard vectors from the sketches is very important, however, this is still lacking for real applications. Methods: In this article, we propose a method for automatically converting the hand-drawn design drawings of a tower into standard vector diagrams. The network ControlNet is introduced to control the image generation model Stable Diffusion, to convert hand-drawn sketches into standard line-structural diagrams. Then, a vectorization network is used to vectorize the line structure, and some designed optimization modules are proposed to refine the vector extraction results. Results: Experiments prove that our method can output the most accurate and robust vectorization results compared with some state-of-the-art methods. Conclusion: The proposed method is automatic and does not need manual operations, which can bring convenience for the intelligent design and modeling of transmission towers. Furthermore, it can also provide technical support for developing relevant digital products for the smart grid.OPEN ACCESS Received: 31/10/2024 Accepted: 13/02/2025 Published: 30/05/202
A Critical Analysis of Pakistan’s 2021 National Climate Change Policy: Ambition vs. Implementation
No full textPakistan’s 2021 National Climate Change Policy (NCCP) articulates an ambitious goal: to steer the country toward “climate compatible development” – i.e. resilient, low-carbon growth . It lists 14 broad objectives (from sustaining growth while addressing climate impacts to building resilient infrastructure, protecting food/water security, and enhancing capacity ). The policy spans adaptation (water, agriculture, health, forestry, coastal and mountain ecosystems, disaster preparedness) and mitigation (energy, transport, industry, waste, carbon sequestration) across multiple sectors . Institutional mechanisms are envisaged: climate-change cells in federal/provincial ministries, inter-ministerial coordination bodies, and dedicated NCCP implementation committees at federal and provincial levels. 
Simplified Electromagnetic Method for the Analytical Euclidean Modeling of Multiple Electrical Conductors in Arbitrary Directions
Get PDFThe analytical modeling of electromagnetic fields generated by multiple current-carrying conductors is fundamental in power systems, electromagnetic compatibility, and transmission line analysis. Traditional analytical methods often assume conductors aligned with the coordinate system axes, limiting their applicability to arbitrary configurations. This paper presents a novel analytical approach that determines the exact electric and magnetic fields for multiple conductors oriented in arbitrary directions within a Euclidean space, assuming linear, homogeneous, and isotropic media. Unlike numerical methods, such as the Finite Element Method (FEM), which require extensive meshing and domain discretization, the proposed method directly computes field vectors without interpolation or artificial boundary conditions. The applicability of the method is evaluated through four case studies, demonstrating its effectiveness in various configurations, including power transmission lines, communication cables, and grounding systems in homogeneous isotropic media. Additionally, a comparative analysis is performed using a specific case with a known analytical solution, validating the method against FEM-based solvers such as ANSYS Maxwell and FEMM. The results confirm that the proposed approach achieves higher accuracy with significantly lower computational costs.OPEN ACCESS Received: 10/03/2025 Accepted: 09/06/2025 Published: 30/06/202
Numerical Study of a Vertical Axis Wind Turbine with an Inner Cylindrical Deflector
Get PDFClimate change demands innovative renewable energy solutions, with wind energy emerging as a key resource. Vertical-axis wind turbines (VAWTs) are particularly suited for low-speed, turbulent wind environments due to their ability to capture wind from all directions. However, VAWTs face aerodynamic difficulties, especially at the downwind, where problems like negative torque and decreased efficiency are frequent. This study explores a novel solution for enhancing VAWT performance by incorporating an inner cylindrical deflector aimed at optimizing airflow around the blades. Using computational fluid dynamics (CFD) simulations, the study focuses on a three-bladed H-type VAWT with an airfoil profile of NACA0018 at a turbine diameter of 1 m. The simulations begin by evaluating a bare turbine arrangement, which shows negative torque beginning at an azimuth angle of about 165 degrees onwards. When a cylindrical deflector of different diameters is introduced, the torque coefficient and overall performance are greatly enhanced by a 0.3-meter diameter. The cylindrical deflector’s effectiveness is demonstrated by the 15% increase in power coefficient C pthat results from its inclusion. These results highlight how an inner cylindrical deflector could be a useful addition to VAWTs, resolving significant inefficiencies while preserving a positive angle of attack. This strategy offers a way forward for more effective VAWT designs in renewable energy systems in addition to increasing energy output. To enhance the efficiency of vertical-axis wind turbines (VAWTs) for both urban and rural applications, future research could investigate different configurations and empirically confirm these findings.OPEN ACCESS Received: 21/01/2025 Accepted: 10/03/2025 Published: 20/04/202
Coupled Magnetothermal Effects in Biomagnetic Fluid Flow over a Stretched Sheet with Copper Nanoparticles
Get PDFThe study of biomagnetic nanofluids has gained significant attention due to their applications in biomedical engineering and thermal management systems, where precise control of heat and fluid flow is crucial. This research investigates the coupled effects of a magnetic dipole, thermal radiation, and copper nanoparticles on biomagnetic nanofluid flow over a stretching sheet to analyze their impact on velocity and temperature distribution. The governing equations are solved numerically using MATLAB’s bvp4c solver over the computational domain [0, 20], and results are validated against benchmark studies to ensure accuracy. Findings reveal that increasing nanoparticle volume fraction enhances thermal conductivity but reduces velocity due to increased viscosity, while stronger ferromagnetic interactions intensify localized heating, significantly altering temperature gradients. Additionally, streamline analysis illustrates the magnetic field’s influence on flow structures, and surface plots provide a comprehensive visualization of heat dissipation within the nanofluid. The study also highlights the role of viscous dissipation and Prandtl number in thermal regulation, offering insights applicable to magnetic hyperthermia treatments, targeted drug delivery, and advanced cooling technologies.OPEN ACCESS Received: 18/02/2025 Accepted: 21/03/2025 Published: 20/04/202
A Human-Computer Collaborative Behavior Measurement Model for Assembly in Constrained Visibility Environments
Get PDFCollision interference detection is an important concern in the manual installation of cable harnesses. Due to the complex and variable layout of cable harness installations, hand assembly movements are prone to collisions, contact, and other forms of interaction with surrounding equipment. Furthermore, cable harnesses often need to be routed along specific paths in visually constrained environments. Currently, there is a lack of modeling in the extraction of hand motion parameters and the data analysis of hand action intent. To address this challenge, we propose a novel human-machine collaboration behavior measurement model. This model not only provides a rapid solution for extracting hand motion parameters but also delivers efficient and natural visual feedback for the behavioral intent reflected by hand motion features. First, we introduce a hand motion parameter extraction mechanism based on a hand kinematics model. Second, we develop a virtual-to-real spatial registration model specifically designed for visually constrained conditions, enabling accurate recognition and 3D calibration of hand action intent. A user study experiment demonstrates that the proposed model outperforms traditional hand behavior measurement models in terms of manual task efficiency, hand motion recognition accuracy, and the naturalness of hand interactions. This improvement is particularly evident in visually constrained environments, effectively addressing challenges in obstacle avoidance and intent inference during spatially constrained assembly tasks.OPEN ACCESS Received: 10/09/2024 Accepted: 08/11/2024 Published: 20/04/202