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Abstract Background Accurate breed identification is essential for the conservation and sustainable use of indigenous farm animal genetic resources. In this study, we evaluated the phylogenetic relationships and genomic breed compositions of 13 sheep breeds using SNP and InDel data from whole genome sequencing. The breeds included 11 Chinese indigenous and 2 foreign commercial breeds. We compared different strategies for breed identification with respect to different marker types, i.e. SNPs, InDels, and a combination of SNPs and InDels (named SIs), different breed-informative marker detection methods, and different machine learning classification methods. Results Using WGS-based SNPs and InDels, we revealed the phylogenetic relationships between 11 Chinese indigenous and two foreign sheep breeds and quantified their purities through estimated genomic breed compositions. We found that the optimal strategy for identifying these breeds was the combination of DFI_union for breed-informative marker detection, which integrated the methods of Delta, Pairwise Wright's FST, and Informativeness for Assignment (namely DFI) by merging the breed-informative markers derived from the three methods, and KSR for breed assignment, which integrated the methods of K-Nearest Neighbor, Support Vector Machine, and Random Forest (namely KSR) by intersecting their results. Using SI markers improved the identification accuracy compared to using SNPs or InDels alone. We achieved accuracies over 97.5% when using at least the 1000 most breed-informative (MBI) SI markers and even 100% when using 5000 SI markers. Conclusions Our results provide not only an important foundation for conservation of these Chinese local sheep breeds, but also general approaches for breed identification of indigenous farm animal breeds.

The study is based on 162 Agricultural Cooperatives in Zhejiang Province. On the basis of literature, this paper analyzes the service situation of agricultural production cooperatives, including production, processing and financing. The influencing factors are discussed theoretically and tested empirically. The study concluded that most cooperatives provide pre-and post-production supply services to participating members, as well as financing services. In addition, in order to strengthen human resources, the leaders of each cooperative are encouraged and the service awareness of the agricultural industrial chain of the cooperative is enhanced; the membership is expanded to facilitate agricultural production and the provision of financing services by the cooperative. At the same time, the increase in post-natal strength provides a positive impact on cooperatives and optimizes the overall market environment for cooperatives. Of course, the agricultural industrial chain services provided by cooperatives are also affected by the variety of products.

This research presents a bibliometric analysis focusing on practical applications of computer vision in transportation systems. The study offers a nuanced understanding of the topic, emphasizing its relevance to areas such as traffic surveillance, management, and road safety. By synthesizing insights from various studies, the analysis provides a comprehensive overview that serves as a valuable foundation for informed decision-making by policymakers and practitioners. The discussion not only highlights current applications but also identifies gaps and limitations in the existing literature. Furthermore, the study offers future directions for the integration of computer vision technologies into diverse transportation scenarios and suggests innovative ideas to overcome current limitations.

In order to evaluate the mechanical condition and working performance of a rigid frame bridge after reconstruction and extension, the mechanical performance of the bridge was analyzed by static load test. Static load test is the test of stress at each section of main beam under the action of partial load and medium load. The results show that, under the action of each load, the check coefficient of strain and deflection at each measuring point of the box girder does not exceed the standard limit value 1, the relative residual strain or deformation at each measuring point does not exceed the standard limit value 20%, the stress condition of the tested section of the box girder is normal, and the structure is under the normal stress state under the action of the test load.

In order to evaluate the stress state and working performance of a rigid frame bridge after reconstruction and extension, load test and transverse load distribution were carried out. Static load test is the test of stress at each section of main beam under the action of partial load and medium load. Dynamic load test is used to test the inherent fundamental frequency, damping ratio and impact coefficient of the bridge through pulsation test and sports car test. The results show that the first order vibration of the bridge is mainly transverse vibration from the measured modal parameters, which is consistent with the characteristics of higher pier and greater flexibility. The vibration characteristics of the bridge structure are low frequency and small damping vibration, the value of which belongs to the normal range among similar bridge structures, the overall stiffness of the bridge structure is normal, and the measured impact coefficient during the test of sports car is less than the design impact coefficient, indicating that the dynamic stiffness of the bridge meets the design and specification requirements.