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Transforming Education with Photogrammetry:Creating Realistic 3D Objects for Augmented Reality Applications

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 185-208页

作者： Kaviyaraj Ravichandran Uma Mohan Department of Computational intelligence School of ComputingSRM Institute of Science and TechnologyKattankulathur603203India

Augmented reality(AR)is an emerging dynamic technology that effectively supports education across different *** increased use of mobile devices has an even greater *** the demand for AR applications in education continues to increase,educators actively seek innovative and immersive methods to engage students in ***,exploring these possibilities also entails identifying and overcoming existing barriers to optimal educational ***,this surge in demand has prompted the identification of specific barriers,one of which is three-dimensional(3D)*** 3D objects for augmented reality education applications can be challenging and time-consuming for the *** address this,we have developed a pipeline that creates realistic 3D objects from the two-dimensional(2D)*** for augmented and virtual reality can then utilize these created 3D *** evaluated the proposed pipeline based on the usability of the 3D object and performance ***,with 117 respondents,the co-creation team was surveyed with openended questions to evaluate the precision of the 3D object created by the proposed photogrammetry *** analyzed the survey data using descriptive-analytical methods and found that the proposed pipeline produces 3D models that are positively accurate when compared to real-world objects,with an average mean score above *** study adds new knowledge in creating 3D objects for augmented reality applications by using the photogrammetry technique;finally,it discusses potential problems and future research directions for 3D objects in the education sector.

关键词： Augmented reality education immersive learning 3D object creation photogrammetry and StructureFromMotion

Improved model for defect detection in photovoltaic cells based on Yolov5

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Optoelectronics Letters 2025年

作者： BAI Xinfeng XUE Yuming DAI Hongli WANG Luoxin BAI Xin HU Xiaofeng institute of New Energy intelligence equipment， School of Integrated Circuit Science and Engineering， Tianjin University of Technology

In order to meet the requirements of recognition speed and accuracy for complex photovoltaic (PV) cell defect detection tasks， this paper proposed an improvement strategy based on the Yolov5 network model. First， the model's ability to localize defects was enhanced by adding shallow feature inputs to strengthen the model's fusion of shallow feature information; second， the Squeeze-and-excitation (SE) attention mechanism was introduced to expand the receptive field and strengthen the dependency between feature channels; finally， a smoothing downsampling module was constructed to replace the convolutional sampling， which reduced the loss of information while retaining the important features. The experimental results show that the Yolov5 model based on this improved strategy achieved an average accuracy of 92.06% in the multiclassification defect detection task， and the average recognition speed reached 25.31 frames per second (FPS)， which took into account the requirements of performance and real-time performance， and can satisfy the needs of PV cell defect detection in industrial scenarios.

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The effects of selenization conditions on the microstructure and optoelectronic properties of CZTSSe absorber layers prepared by the sol-gel method

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Optoelectronics Letters 2025年

作者： BAI Xin XUE Yuming DAI Hongli WANG Luoxin BAI Xinfeng HU Xiaofeng institute of New Energy intelligence equipment， School of Integrated Circuit Science and Engineering， Tianjin University of Technology

Cu2ZnSnSSe4（CZTSSe） thin film solar cells， with adjustable bandgap and rich elemental content， hold promise in next-gen photovoltaics. Crystalline quality is pivotal for efficient light absorption and carrier transport. During the post-selenization process， understanding crystal growth mechanisms， and improving layer quality are essential. We explored the effects of ramp rate and annealing temperature on CZTSSe films， using XRD， Raman， SEM， and UV-Vis. The optimal performance occurred at 25.25 ℃/min ramp rate and 530℃ annealing. This led to smoother surfaces， higher density， and larger grains. This condition produced a single-layer structure with large grains， no secondary phases， and a 1.14 eV bandgap， making it promising for photovoltaic applications. The study has highlighted the effect of selenization conditions on the characteristics of the CZTSSe absorber layer and has provided valuable information for developing CZTSSe thin film solar cells.

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Enhancing the performance of the absorber of Cu2ZnSn（S， Se）4 photovoltaic materials by doping Cd2+

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Optoelectronics Letters 2025年

作者： YANG Shuqi XUE Yuming DAI Hongli WANG Luoxin ZHANG Haiwei BAI Xin institute of New Energy intelligence equipment， School of Integrated Circuit Science and Engineering， Tianjin University of Technology

Cationic doping is considered to be an effective way to improve the efficiency of Cu2ZnSn（S，Se）4（CZTSSe） photovoltaic materials. To improve the quality of the absorption layer of the crystal film， CZTSSe film was doped with some Cd to change the ratio of Cd and Zn in the precursor solution. XRD， Raman， SEM， UV-Vis spectroscopy， and other results showed that Cd successfully replaced Zn in the crystal lattice during post-selenization. The formation of harmful Zn-related defects was reduced， the grain size and crystallinity of the films were significantly increased， and the photoelectric properties of the films such as crystal quality and structural morphology were improved. As the Cd/（Cd+Zn） ratio increased from 0 to 0.35， the band gap of CZCTSSe decreased to 1.02eV. When Cd/（Cd+Zn）=0.25， the crystallinity and grain size reached the best value， and the film surface was smooth and dense， which inhibited the formation of the second phase on the surface of *** theoretical basis and experimental results showed that proper Cd doping can promote the growth of grain， so that compact CZCTSSe films with larger grain sizes and fewer holes could be prepared.

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Influence of band gap and different defects on the performance of Cu（In， Ga）Se2 solar cells

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Optoelectronics Letters 2025年

作者： LU Yahan XUE Yuming DAI Hongli WANG Luoxin LI Weiwei JI Licui institute of New Energy intelligence equipment， School of Integrated Circuit Science and Engineering， Tianjin University of Technology

The SCAPS-1D simulator， a one-dimensional solar cell capacitance simulator is utilized for simulating CIGS solar cells. It has been observed that the performance of solar cells can be enhanced by uniformly adjusting the band gap value of the CIGS absorption layer. Upon doing so， the solar cell's conversion efficiency reaches 22.13% when the band gap of the CIGS absorption layer is 1.3eV. Subsequently， the influence of defect type and density on photoelectric properties is analyzed by using the improved absorption band gap. The findings indicate that to heighten the photovoltaic efficiency， it is imperative to minimize the defect concentration in the absorption layer， as high-density defects significantly impact the efficiency， and can even render the conversion efficiency to zero. This study underscores the pivotal influence of band gap adjustments and defect charge types on the photoelectric properties of thin film solar cells.

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Effect of ammonia concentration of complexing agent on CdxZn1-xS buffer layer by chemical bath deposition and performance of CIGS cell

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Optoelectronics Letters 2025年

作者： LU Yahan XUE Yuming DAI Hongli WANG Luoxin ZHOU Liwei TAN Zhiyuan institute of New Energy intelligence equipment， School of Integrated Circuit Science and Engineering， Tianjin University of Technology

In this paper， CdxZn1-xS thin films were deposited on glass substrates by chemical bath deposition （CBD），and the effects of different concentrations of ammonia water on the morphology， structure and optical properties of the films were studied. CdxZn1-xS thin films have hexagonal crystal structure， the transmittance is above 75% in the visible range， and the optical band gap is between 2.6 eV and 2.9 eV. The influence of the experimental group of deposited thin films on the performance parameters of the CIGS battery was studied by simulation with SCAPS-1D software and the cell efficiency reached 22.42%. It is introduced that the buffer layer prepared in this experiment is feasible in CIGS solar cells.

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High-precision tip positioning composite feedforward control of linear colocated motion systems with Bi-Loop iterative feedforward tuning

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Science China Technological Sciences 2025年

作者： Junyu HU Yourui TAO Shanhu LI Xu HAN College of Mechanical and Vehicle Engineering Hunan University State Key Laboratory of Reliability and intelligence of Electrical equipment Hebei University of Technology

To enhance the tip positioning accuracy and robustness against disturbances of linear colocated motion systems, a novel composite feedforward (COMFF) control with Bi-Loop iterative feedforward tuning (IFFT) is proposed. The tip positioning error consists of the coupled tip residual vibration and linear motor tracking error. Given the influence of nonlinear friction and load flexibility, the topology of COMFF is designed as decoupled structures so that COMFF can suppress the tip residual vibration and compensate for the linear motor tracking error compatibly. Furthermore, Bi-Loop IFFT is built to improve the robustness of COMFF in high-precision motor tracking performance. In the state space of the linear motor tracking error based on the projection theorem, two loops are performed in parallel along the iteration direction. One is the P-type iteration loop that drives linear motor tracking errors to converge to the zero state. The other is the observation loop constructed by the recursive least square with forgetting factors to accelerate the P-type iteration loop. Driven by the P-type iteration loop with the aid of the observation loop, the proposed COMFF is integrated with fast convergence and high robustness when confronted with model disturbances. The effectiveness of the proposed COMFF combined with Bi-Loop IFFT is validated by experiments.

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Traffic safety helmet wear detection based on improved YOLOv5 network

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Optoelectronics Letters 2025年第1期21卷 35-42页

作者： GUI Dongdong SUN Bo College of Software Southeast University Quanzhou equipment Research Centre Haixi Institute Chinese Academy of Sciences

Aiming at the problem that the current traffic safety helmet detection model can't balance the accuracy of detection with the size of the model and the poor generalization of the model, a method based on improving you only look once version 5(YOLOv5) is proposed. By incorporating the lightweight Ghost Net module into the YOLOv5 backbone network, we effectively reduce the model size. The addition of the receptive fields block(RFB) module enhances feature extraction and improves the feature acquisition capability of the lightweight model. Subsequently, the high-performance lightweight convolution, GSConv, is integrated into the neck structure for further model size compression. Moreover, the baseline model's loss function is substituted with efficient insertion over union(EIoU), accelerating network convergence and enhancing detection precision. Experimental results corroborate the effectiveness of this improved algorithm in real-world traffic scenarios.

关键词： Traffic control

Equivalent combined cycle modelling for three-heat-reservoir thermal Brownian heat pump with heat-transfer effect and its optimal performance

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Science China Technological Sciences 2025年

作者： Lingen CHEN Congzheng QI Yanlin GE Huijun FENG Hubei Provincial Key Laboratory of Chemical equipment Intensification and Intrinsic Safety Wuhan Institute of Technology Hubei Provincial Engineering Technology Research Center of Green Chemical equipment Wuhan Institute of Technology institute of Thermal Science and Power Engineering Wuhan Institute of Technology School of Mechanical & Electrical Engineering Wuhan Institute of Technology

Because of the important role of the absorption heat pump in low-grade thermal energy utilization, this paper extends it to micro domain and performs a finite-time thermodynamic modelling for a three-heat-reservoir (THR) thermal Brownian heat pump with heat transfer effect by using an equivalent combined cycle method, which was applied for macro endoreversible THR heat pumps. The working principle and energy transformation rule are studied, and the coefficient of performance (COP) and heating load are derived. With a fixed overall thermal conductance of three heat exchangers, the maximal heating load is determined by optimizing thermal conductance distributions among three heat exchangers and barrier height, and the optimal working temperatures are also obtained. The impact of external heat transfer is elucidated to show the difference between this model and a non-equilibrium thermodynamic one. Results indicate that external heat transfer determines the energy transformation directly, and performance characteristics are closer to reality when external heat transfer is considered. The heating load has a maximal value about thermal conductance allocation ratios. About half the overall heat exchanger inventory needs to be assigned to the heat exchanger of the heating space for maximal heating load. When the cycle is with only heat transfer effect, the net particle numbers are zero, and the cycle fails to pump heat. The research results are expected to offer an idea for thermodynamic optimization and design of micro THR thermal Brownian heat pump devices.

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