There are few studies on the land subsidence induced by shield tunneling in the water-rich sandy gravel stratum, which is of high research value. Linear regression and measured data were employed in this study to investigate the land subsidence induced by shield tunneling when crossing the water-rich sandy gravel stratum from Mudan Dadao Station to Longmen Dadao station of Luoyang Metro Line 2. The maximum land subsidence correction coefficient, α, and the settlement trough width correction coefficient, β, were introduced to modify the peck formula to predict land subsidence induced by shield tunneling in Luoyang’s water-rich sandy gravel stratum. It was discovered that the original Peck formula needs to be modified because its prediction result was significantly larger than the actual value. When the value ranges of α and β in the modified Peck formula were 0.379~0.690 and 0.455~0.508, respectively, the modified Peck formula presented a minor error, in terms of the prediction curve, compared with the original formula, and the prediction result was more reliable. The best prediction result could be obtained when α = 0.535 and β = 0.482. In addition, Python could effectively improve the calculation efficiency of the Peck formula modification.

Online higher education has become a steadily more popular way of learning for university students in the post-pandemic era. It has been emphasized that active learning and interactive communication are key factors in achieving effective performance in online learning. However, due to the lack of learning motivation of students and the lack of feedback data in online learning, there are numerous problems, such as the weak self-discipline of students, unsatisfactory learning experience, a high plagiarism rate of homework, and the low utilization of online teaching resources. In this study, an online homework intelligent platform implemented by information technology (IT) was proposed. It was based on the pedagogical self-regulated learning (SRL) strategy as a theoretical foundation, and information technology as a driver. Through setting online homework assignments, a sustainable means of promoting the four components of the SRL strategy, i.e., self-disciplinary control, independent thinking, reflective learning, and interest development, can be provided to university students. Therefore, this study explained the “4A” functions in the platform and analysed the details of their implementation and value, such as assistance in locating resources, assignment of differentiated homework, assessment of warning learning, and achievement of sharing. After three years of continuous improvements since COVID-19, this online platform has been successfully applied to students and teachers at our university and other pilot universities. A comparison of student teaching data, questionnaire responses and teacher interviews from the Computer Composition Principles course illustrated the sustainability as well as the effectiveness of the method.

Teachers need a technique to efficiently understand the learning effects of their students. Early warning prediction mechanisms constitute one solution for assisting teachers in changing their teaching strategies by providing a long-term process for assessing each student’s learning status. However, current methods of building models necessitate an excessive amount of data, which is not conducive to the final effect of the model, and it is difficult to collect enough information. In this paper, we use educational data mining techniques to analyze students’ homework data and propose an algorithm to extract the three main features: Degree of reliability, degree of enthusiasm, and degree of procrastination. Building a predictive model based on homework habits can provide an individualized evaluation of students’ sustainability processes and support teachers in adjusting their teaching strategies. This was cross-validated using multiple machine learning algorithms, of which the highest accuracy was 93.34%.

Low-permeability reservoirs have become an important field of oil and gas development in China. CO₂ flooding technology is an effective technical means for tertiary oil recovery. Although the asphaltene in the system is deposited in the form of a solid after CO₂ injection into the reservoir in contact with crude oil, which causes a certain blockage to the reservoir, the dissolution during the injection process improves the seepage capacity of the reservoir as a whole, and the damage degree of CO₂ flooding to low-permeability reservoirs under different injection modes is different. In this paper, the damage degree of asphaltene precipitation to low-permeability reservoirs under different injection modes of CO₂ flooding is quantitatively characterized. The mechanism experiment of organic scale plugging after continuous CO₂ flooding and CO₂–water alternate flooding, the wettability experiment of reservoirs, and the evaluation experiment of CO₂–water solution on rock dissolution are carried out, and the variation characteristics of relative permeability curve parameters are evaluated. In this paper, the damage degree of asphaltene precipitation to low-permeability reservoirs under different injection modes of CO₂ flooding is quantitatively characterized. The mechanism experiment of organic scale plugging after continuous CO₂ flooding and CO₂–water alternate flooding, the wettability experiment of reservoirs, and the evaluation experiment of CO₂–water solution on rock dissolution are carried out. The variation characteristics of relative permeability curve parameters are evaluated. The results show that the organic scale produced by CO₂ flooding will block the pore throat of the rock, but, on the whole, the dissolution caused by the reaction of CO₂ and chlorite is stronger, which makes the recovery rate of low-permeability reservoirs effectively improved. The organic scale blockage caused by CO₂–water alternating flooding is weaker than that caused by continuous CO₂ flooding. The dissolution effect is better and the permeability is higher. It can achieve a better oil displacement effect in pores with a pore size greater than 0.2 μm. On the whole, it can increase the core pore space and seepage channel, so that the recovery rate of low-permeability reservoirs can be effectively improved. This study has important theoretical and practical significance for improving oil recovery in low-permeability reservoirs.

In the past, the teaching of C programming courses was teacher-centered, and students’ practical ability, innovation ability, independent learning ability, and moral character were not effectively improved. In order to meet the requirements of teaching informatization, OBE philosophy, “Golden Course” construction, and ideological politics in the curriculum for course teaching, we have been reforming how C programming courses are taught since 2013 from the perspective of sustainable development in order to realize the synergistic promotion of knowledge imparting, ability training, and moral character shaping. First, we systematically reformed the teaching support system in eight dimensions: changing the teaching philosophy, enriching teaching resources, reconstructing the teaching environment, reshaping the course content, transforming the teaching process, innovating teaching methods, reforming course evaluations, and building ideological politics surrounding the ecology of the curriculum. On this basis, we divided the teaching classroom into three classrooms: theory, practical training, and innovative practice. We ensured that teaching resources, information technology, diversified evaluation, and moral character shaping were always integrated into the classroom. Then, we used a combination of “online and offline, in-class knowledge learning and extra-curricular autonomous practice, teachers’ careful lectures and seniors’ guidance, ability training and moral character shaping, and impart knowledge and innovative practice” to build a student-centered teaching model of “three classrooms–four integrations–five combinations”. Since the application of this model in course teaching, students have not only enhanced their sense of access to learning and improved their course performance, independent learning ability, and practical ability, but have also improved their innovation ability, with students achieving excellent results in thesis publication, patent applications, software copyright applications, discipline competitions, and innovation project applications. Students have cultivated a strong sense of social responsibility and high moral character, and employers are highly satisfied. This teaching model has been adopted and reused in 12 engineering courses and has achieved good application results. The teaching model can provide a reference for college engineering courses to build a student-centered information-based education ecology, create high-quality classrooms, and collaboratively improve students’ abilities and moral character.

To effectively reduce the cost of firmware upgrade and maintenance of embedded devices, according to the requirement of a remote firmware update of embedded devices, this paper proposes a remote online firmware upgrade technology based on ZigBee. Combined with the requirements of remote online firmware upgrade application of tower-mounted amplifier, this paper analyzes and studies the system requirements, ZigBee module selection and design, software design and implementation (communication protocol design of host and slave program, breakpoint continuation function), fault analysis and other aspects. Designed experiments and tested the ZigBee connection success rate under the device startup state and normal operation state, the relationship between transmission firmware size and transmission success rate, system CPU resource consumption, transmission distance, transmission rate, the success rate, data reuse rate and acceleration ratio of breakpoint continuation function, and other performance indicators. The experimental results show that the remote online firmware upgrade technology based on ZigBee for embedded devices can better meet the system’s performance requirements in all aspects and improve the data reuse rate and acceleration ratio in the process of data transmission. The experimental results show that this scheme has the advantages of simplicity, low cost, high reliability, and broad application prospects.