SEISMIC DAMAGE FIELD OBSERVATION AND VULNERABILITY ANALYSIS OF MULTILAYER REINFORCED CONCRETE FRAME STRUCTURE

To research the seismic damage characteristics, mechanism and vulnerability of multi-storey reinforced concrete (RC) frame structures, statistics and analysis, were made on 930 RC frame structures in Dujiangyan during Wenchuan earthquake, China. Firstly, seismic damage of RC frame structure in Dujiangyan is investigated comprehensively. According to the investigation results, easily damaged locations of this kind of structural system are: infilled wall, frame column, beam-column, joints and stairs. However, a large number of RC frame structures are basically intact or slightly damaged. By using the method of numerical statistical analysis, the non-linear relationship model and the fitting curve of seismic damage investigation samples under multiple seismic damage grades are given. Considering the number of stories, multiple ages and seismic fortification influencing factors, the empirical seismic damage situation of structures under each factor is analyzed, and the non-linear regression curve is developed. The empirical seismic vulnerability matrix and continuous regression function model and curve of RC frame structure in multi-intensity region are established. A calculation model of mean seismic damage index (MSDI) is proposed, and the vulnerability matrix and regression curve based on this parameter are given in combination with the empirical seismic damage investigation data. The above research results can provide a basic reference for vulnerability analysis and intensity scale revision of RC structures

Disfrute de lenguas extranjeras y ansiedad en aula de idiomas para estudiantes chinos de alemán

This study was supported by the National Social Science Fund of China (Grant No. 19WZXB011) and the Humanities and Social Sciences Youth Foundation of the Ministry of Education of China (Grant No. 22YJC740047).This study examines both the foreign language enjoyment (FLE) and the foreign language classroom anxiety (FLCA) of 201 Chinese university students of non-German majors who were learning the German language. A questionnaire based on the FLE scale and the FLCA scale was employed to examine the participants’ classroom emotions as well as other learner- and teacher-related variables. Participants reported a higher level of FLE than FLCA, with these two emotions being negatively correlated. Also, regression analysis showed that FLE can be strongly predicted by teacher-related variables, while FLCA is predicted by learner-related variables. Moreover, qualitative analysis of the open-ended questions in the questionnaire showed that learners’ FLE in the German classroom was boosted by their sense of achievement in learning a new language and frequent interaction between the participants and their teachers and classmates. At the same time, the relatively high demands of German language learning and frequent exams resulted in higher FLCA. The findings suggest that teachers could organize diverse classroom activities and integrate more culture-related content to enhance their students’ FLE. Meanwhile, they could also adopt more flexible methods of assessment and provide clearer instructions thereon to help students to be more prepared, thereby ameliorating their FLCA.El presente estudio profundiza en el disfrute de lenguas extranjera (FLE) y ansiedad en el aula de lenguas extranjeras (FLCA) de 201 universitarios chinos de carreras no alemanas. Se empleó un cuestionario basado en escalas FLE y FLCA para examinar emociones en el aula de los participantes, y otras variables relacionadas con el alumno y el profesor. Los participantes mostraron un mayor nivel de FLE que FLCA, y que estas dos emociones estaban negativamente correlacionadas. El análisis de regresión demostró que FLE puede ser fuertemente predicha por variables relacionadas con el profesor y FLCA, por las con el alumno. Además, el análisis cualitativo de las preguntas abiertas manifestó que el FLE se vio impulsado por la sensación de logro en el aprendizaje de una nueva lengua y la frecuente interacción entre los participantes y sus profesores y compañeros. Simultáneamente, causaron una mayor FLCA la exigencia relativamente alta del aprendizaje del alemán y exámenes frecuentes. Según los resultados, sugerimos que los profesores organicen diversas actividades en el aula e integren más contenidos vinculados con la cultura para mejorar el FLE estudiantil. Mientras tanto, pueden adoptar formas más flexibles de evaluación e instrucciones más claras para prepararles más, mejorando así su FLCA.National Social Science Fund of China (19WZXB011)Ministry of Education of China (22YJC740047

Enhancing the Protein Tertiary Structure Prediction by Multiple Sequence Alignment Generation

The field of protein folding research has been greatly advanced by deep learning methods, with AlphaFold2 (AF2) demonstrating exceptional performance and atomic-level precision. As co-evolution is integral to protein structure prediction, AF2's accuracy is significantly influenced by the depth of multiple sequence alignment (MSA), which requires extensive exploration of a large protein database for similar sequences. However, not all protein sequences possess abundant homologous families, and consequently, AF2's performance can degrade on such queries, at times failing to produce meaningful results. To address this, we introduce a novel generative language model, MSA-Augmenter, which leverages protein-specific attention mechanisms and large-scale MSAs to generate useful, novel protein sequences not currently found in databases. These sequences supplement shallow MSAs, enhancing the accuracy of structural property predictions. Our experiments on CASP14 demonstrate that MSA-Augmenter can generate de novo sequences that retain co-evolutionary information from inferior MSAs, thereby improving protein structure prediction quality on top of strong AF2

Design of a Conceptual Bumper Energy Absorber Coupling Pedestrian Safety and Low-Speed Impact Requirements

The car front bumper system needs to meet the requirements of both pedestrian safety and low-speed impact which are somewhat contradicting. This study aims to design a new kind of modular self-adaptive energy absorber of the front bumper system which can balance the two performances. The X-shaped energy-absorbing structure was proposed which can enhance the energy absorption capacity during impact by changing its deformation mode based on the amount of external collision energy. Then, finite element simulations with a realistic vehicle bumper system are performed to demonstrate its crashworthiness in comparison with the traditional foam energy absorber, which presents a significant improvement of the two performances. Furthermore, the structural parameters of the X-shaped energy-absorbing structure including thickness (tu), side arc radius (R), and clamping boost beam thickness (tb) are analyzed using a full factorial method, and a multiobjective optimization is implemented regarding evaluation indexes of both pedestrian safety and low-speed impact. The optimal parameters are then verified, and the feasibility of the optimal results is confirmed. In conclusion, the new X-shaped energy absorber can meet both pedestrian safety and low-speed impact requirements well by altering the main deformation modes according to different impact energy levels