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Simple Summary: Through beef cattle behavior recognition technology, livestock farmers can promptly identify abnormal behaviors in beef cattle, providing data and technological support for intelligent and welfare-oriented cattle farming. This study is based on computer vision's convolutional neural networks. It constructs a new method for the real-time detection of beef cattle behavior by optimizing the convolutional module and adding attention mechanisms. The method is evaluated on nine behavior datasets, including standing, lying, mounting, fighting, licking, eating, drinking, walking, and searching. It significantly improves the performance of beef cattle behavior recognition, achieving an average accuracy of 96.5%, which serves as a foundation for beef cattle health assessment and information-based farming. Behavior recognition in beef cattle is a crucial component of beef cattle behavior warning and intelligent farming. Traditional beef cattle behavior recognition faces challenges in both difficulty in identification and low accuracy. In this study, the YOLOv8n_BiF_DSC (Fusion of Dynamic Snake Convolution and BiFormer Attention) algorithm was employed for the non-intrusive recognition of beef cattle behavior. The specific steps are as follows: 45 beef cattle were observed using a fixed camera (A LINE OF DEFENSE) and a mobile phone (Huawei Mate20Pro) to collect and filter posture data, yielding usable videos ranging from 1 to 30 min in length. These videos cover nine different behaviors in various scenarios, including standing, lying, mounting, fighting, licking, eating, drinking, walking, and searching. After data augmentation, the dataset comprised 34,560 samples. The convolutional layer (CONV) was improved by introducing variable convolution and dynamic snake-like convolution modules. The dynamic snake-like convolution, which yielded the best results, expanded the model's receptive field, dynamically perceived key features of beef cattle behavior, and enhanced the algorithm's feature extraction capability. Attention mechanism modules, including SE (Squeeze-and-Excitation Networks), CBAM (Convolutional Block Attention Module), CA (Coordinate Attention), and BiFormer (Vision Transformer with Bi-Level Routing Attention), were introduced. The BiFormer attention mechanism, selected for its optimal performance, improved the algorithm's ability to capture long-distance context dependencies. The model's computational efficiency was enhanced through dynamic and query-aware perception. Experimental results indicated that YOLOv8n_BiF_DSC achieved the best results among all improved algorithms in terms of accuracy, average precision at IoU 50, and average precision at IoU 50:95. The accuracy of beef cattle behavior recognition reached 93.6%, with the average precision at IoU 50 and IoU 50:95 being 96.5% and 71.5%, respectively. This represents a 5.3%, 5.2%, and 7.1% improvement over the original YOLOv8n. Notably, the average accuracy of recognizing the lying posture of beef cattle reached 98.9%. In conclusion, the YOLOv8n_BiF_DSC algorithm demonstrates excellent performance in feature extraction and high-level data fusion, displaying high robustness and adaptability. It provides theoretical and practical support for the intelligent recognition and management of beef cattle. [ABSTRACT FROM AUTHOR]

Individual identification of pigs is a critical component of intelligent pig farming. Traditional pig ear-tagging requires significant human resources and suffers from issues such as difficulty in recognition and low accuracy. This paper proposes the YOLOv5-KCB algorithm for non-invasive identification of individual pigs. Specifically, the algorithm utilizes two datasets—pig faces and pig necks—which are divided into nine categories. Following data augmentation, the total sample size was augmented to 19,680. The distance metric used for K-means clustering is changed from the original algorithm to 1-IOU, which improves the adaptability of the model's target anchor boxes. Furthermore, the algorithm introduces SE, CBAM, and CA attention mechanisms, with the CA attention mechanism being selected for its superior performance in feature extraction. Finally, CARAFE, ASFF, and BiFPN are used for feature fusion, with BiFPN selected for its superior performance in improving the detection ability of the algorithm. The experimental results indicate that the YOLOv5-KCB algorithm achieved the highest accuracy rates in pig individual recognition, surpassing all other improved algorithms in average accuracy rate (IOU = 0.5). The accuracy rate of pig head and neck recognition was 98.4%, while the accuracy rate for pig face recognition was 95.1%, representing an improvement of 4.8% and 13.8% over the original YOLOv5 algorithm. Notably, the average accuracy rate of identifying pig head and neck was consistently higher than pig face recognition across all algorithms, with YOLOv5-KCB demonstrating an impressive 2.9% improvement. These results emphasize the potential for utilizing the YOLOv5-KCB algorithm for precise individual pig identification, facilitating subsequent intelligent management practices. [ABSTRACT FROM AUTHOR]

Taper angle is an important factor for characterizing a hyrocyclone's separation performance. Appropriate setting of the taper angle can contribute to particle grading and separation performance of the hydrocyclone. Through numerical analysis, this study investigated the flow fields and separation performances of the hydrocyclones with different taper angles in depth. Moreover, the numerical simulation results were compared with experimental data of the conventional hydrocyclone for accuracy validation. The results showed that the tangential velocity, axial velocity, and the diameter of air core increased with the increasing taper angle. At a too large or a too small taper angle, the inner flow field would become unstable, thereby leading to the increasing number of dislocated particles and reducing the particle separation precision. For the hydrocyclone with a diameter of 75 mm, the separation precision of fine particles can be remarkably enhanced by setting the taper angle of 15°, accompanied with the improvement of product quality. The present data can provide the related enterprises with favorable guidance and a theoretical foundation for further designing the taper angle of novel hydrocyclones. [ABSTRACT FROM AUTHOR]

Steam-Assisted gravity drainage (SAGD) technique has been successfully applied to unlock the oilsands resources in Canada. But to accurately estimate the steam chamber expansion and productivity of the entire lifetime of a SAGD well pair is still challenging. In this paper, a new comprehensive model is proposed encompassing the different stages of SAGD. Firstly, for the rising stage, based on the theory of volumetric displacement, an analytical model is developed for the rise speed and oil rate. Thereafter, based on Butler's theory, a 2D numerical approach is modelled for predicting the lateral spreading and confinement stage of steam chamber. Thus, combining the two different mathematical models, the steam chamber shape and recovery performance of a SAGD process can be calculated. The calculation results are also compared against 3D experimental results and field data to confirm the accuracy of this model. Then, a sensitivity analysis is performed to discuss the effects of operation parameters on steam chamber expansion and recovery performance of SAGD process. Results indicate that the calculated results can match the experiment results and field date very well. The calculated peak oil production rate causes a large error and the plateau time of SAGD process obviously is shortened if the preheating stage is neglected. A higher steam chamber pressure results in a narrower inverted triangle interface shape in the rising stage and a more concave-like interface in the sideways expansion stage. In addition, the oil rate increases with steam chamber pressure allowing for varying steam injection rate, whereas the increasing trend of ultimate recovery decreases with the steam chamber pressure increases, which indicates that a proper steam chamber pressure to be chosen can not only achieve a preferable ultimate recovery but also benefit for project economics. • A new comprehensive model encompassing different stages of SAGD was developed. • A 3D physical experiment was conducted for verifying the proposed model. • The preheating period has a little impact on the ultimate recovery. • Steam chamber pressure has a great effect on steam chamber evolution. [ABSTRACT FROM AUTHOR]