In September 5, 2022, a M6.8 earthquake occurred in Luding County Sichuan Province. Quite a lot of store-front type buildings damaged or collapsed. Five representative buildings representing both positive and negative aspects were selected to analyze the earthquake damage mechanism through theoretical basis and model experiment. The results show that the earthquake damage is mainly concentrated in the bottom layer, which is composed of concrete column and masonry wall. The masonry wall with no lateral openings restrains the transverse and torsional deformation of the structure, and the floor only transports along the longitudinal direction, and the seismic shear force shared by each member is proportional to its longitudinal lateral stiffness. The rigid and brittle members with large stiffness will appear “internal force condensation”, and then reach “deformation saturation”, and lose the load-bearing capacity in the way of brittle failure, and the gravity of the upper layers will be borne by the transverse wall. If the earthquake does not stop at this time, the transverse wall will lose the role of “buttress” in the direction of exit plane, and the whole structure will collapse along the longitudinal contact with the ground. On the contrary, if the structure of the bottom layer avoids large differences in stiffness, it can significantly improve the seismic resistance.

Aiming at the problem of time-consuming and labor-intensive routing path design in the cable layout design of complex electromechanical products, an automatic routing technology for complex electromechanical product cables based on multi rules particle swarm algorithm was proposed. Firstly, the cable routing environment of electromechanical products was analyzed, and the routing path was abstracted into a sequence of points to complete the definition of cable routing space. Through pose transformation, the problem of difficult interference detection between wiring paths and parts in electromechanical products was solved. In order to make full use of the wiring space, the particle multiple rules were introduced into the particle swarm optimization algorithm. By using particle number, multi-scale collision detection, adjacent waypoint replacement method and fourth-order quasi-uniform B-spline curve method, the problem that the routing environment is complicated and the optimal solution cannot be obtained was solved, and the searching ability, solving speed and routing quality of the algorithm were improved. Through simulation analysis and comparison with other algorithms, the superiority of the algorithm is proved. The example proves that the proposed method can search feasible paths efficiently during routing. The generated routing paths do not interfere with parts in three-dimensional space, and there are no mutation points in the path fairing, which provides a new idea for the automatic routing of complex electromechanical products.

With its advantages in cooling efficiency and cost, the cold channel closed system is more and more used in the construction of new data centers. However, the closed channel system will turn the originally open channels between data center cabinets into narrow spaces with restricted ventilation. When the main combustibles in the data center catch fire, the accumulated hot smoke and gas in the closed channel cannot be timely discharged, seriously threatening the safety of data center equipment and personnel. At present, there is a paucity of experimental data and theoretical basis for the fire hazard of cables commonly used in data centres. Pyrosim software was used to establish a full-size physical model of the data center room in the cold closed channel, and fire dynamics simulator(FDS) software was used to establish a full-size fire model to simulate different fire source locations, so as to analyze the changes of fire parameters such as smoke spread rate, visibility and temperature distribution. The results show that when a fire occurs under the floor (maximum heat release rate reaches 2 000 kW), the smoke would fill the whole machine room more quickly due to the influence of the special air conditioning airflow and floor than the cabinet fire. The visibility at the safety exit measuring point reached 0 m, 60 s earlier than the fire at the inside of the cabinet. At the same time, affected by the air conditioning airflow and perforated tiles, the temperature at the inside of the cabinet quickly reaches the critical value where the fire hazard is much greater. The results could provide important theoretical support for the fire protection system design of the cold channel of closed data center.

Accurately predicting bike-sharing flow is essential for optimizing the supply-demand balance of shared bikes and enhancing urban residents’ travel convenience. To address the issues of low prediction accuracy and insufficient capture of spatiotemporal characteristics in bike-sharing flow prediction, a hybrid convolutional-recurrent neural network (Conv3D-GRU) model was proposed. Using Chicago’s 2022 full-year bike-sharing data, experiments were conducted, and the results were compared with those of the 3D convolutional neural network (3D-CNN) model and the convolutional long short-term memory (ConvLSTM) model. The model performance was evaluated using root mean squared error (RMSE), mean absolute error (MAE), and the coefficient of determination (R²). Experimental results show that compared with the 3D-CNN and ConvLSTM models, Conv3D-GRU is improved by 3.25%, 4.90%, 1.14% and 11.94%, 13.70% and 2.46% on RMSE, MAE and R², respectively. This demonstrates that the Conv3D-GRU model has lower prediction errors and higher prediction accuracy, making it an effective and reliable approach for forecasting bike-sharing inflow and outflow.

The Guocheng-Yazi area in the northeastern margin of the Jiaolai Basin is located in the southern section of the Muping-Rushan gold metallogenic belt. It is an important gold metallogenic area in the Jiaodong region. In recent years, medium-sized and large-scale gold deposits such as Pengjiakuang, Tudui-Shawang, Xijingkou, Liaoshang, Xilaokou, and Qianchuiliu have been successively explored. The cumulative amount of gold resources explored exceeds 180 t. Based on the field work of geological mapping, ore-bearing structure investigation, controlled source audio-frequency magnetotelluric sounding (CSAMT) and drilling engineering, the distribution of ore bodies, geophysical characteristics, ore-controlling structure and metallogenic regularity were analyzd. The western extension position of the Pengjiakuang detachment fault was preliminarily clarified. Extending westward from the Xijingkou to the Liaoshang to the Guocheng fault, which is the ore-controlling structure of Pengjiakuang, Xijingkou, Xilaokou, Qianchuiliu, Liaoshang and other gold deposits. The Queshan metamorphic core complex and its detachment faults are the main ore-controlling structures and favorable ore-forming spaces for gold mineralization in this area, and are important prospecting targets in future exploration and prospecting work. The mineralization depth of the gold deposit concentration area in this area is mainly 5.01~7.93 km, and the gold deposit has just been eroded as a whole. The deep and peripheral areas have good prospecting potential.

The clustering of discontinuity orientation is crucial for revealing the distribution and characteristics of various types of discontinuities. Conventional clustering methods based on discontinuity pole density maps often rely on geological experience and lack objectivity. Therefore, the mean shift clustering algorithm was introduced to study the clustering of discontinuity orientation. Initially, discontinuity orientations with different degrees of dispersion were manually generated. Subsequently, these orientation data were converted into coordinates in 3-D space, and the sinusoidal value γ of the unit normal vector was employed as the similarity measure. The mean shift algorithm was then used to perform clustering analysis on the measured data set. Compared with the conventional pole density map method and the K-means clustering algorithm, the validity test index and clustering error recognition rate were close to those of the K-means clustering algorithm. Finally, taking the Chongqing Sangong rock slope as an example, the rationality and effectiveness of the new method were verified by field data. The results show that the performance of the proposed method surpasses that of the conventional discontinuity pole density map and K-means clustering algorithm. The clustering results are objective and reasonable, and the clustering effect for near-horizontal discontinuities is also satisfactory.

To explore the effects of cardiac magnetic resonance imaging(CMRI) on the assessment of left ventricular function and myocardial changes in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). Thirty-one patients with OSAHS who were admitted to Handan Central Hospital from November 2019 to June 2021 were selected as the observation group, and 30 healthy volunteers who received CMRI monitoring during the same period were selected as the control group.Two sets of parameters related to left ventricular function were compared, including left ventricular ejection fraction (LVEF), left ventricular end diastolic/end systolic volume (LVEDV/LVESV), left ventricular myocardial activity imaging indexes[T1pre value(measurement of T1 relaxation time before enhancement) before mean injection of contrast agent in left ventricular myocardium, 15 min T1post value(T1 value of myocardial tissue measured by T1 mapping technique after using contrast agent in CMRI) and T2 value(transverse relaxation time of myocardial tissue)]after injection,and histological parameter characteristics of different myocardial layers[mean extracellular matrix volume fraction (ECV) of left ventricular myocardium].The left ventricular function parameters (LVEF, LVED) in the observation group are significantly lower than those in the control group, while LVESV and T2 values are significantly higher than those in the control group (P<0.05). There is no significant difference in T1pre, T1post, ECV in basal segment, middle segment and apical segment between the observation group and the control group (P>0.05).CMRI has a significant clinical effect in patients with OSAHS and can effectively assess the left ventricular function, structure and early myocardial lesions.

In order to clarify the depositional environment of the Upper Permian Wutonggou Formation, the Dalongkou section at the southern margin of the Junggar Basin was taken as an example, and the following understanding was obtained by analyzing the lithology, lithofacies types, lithofacies assemblages, and spatial spreading laws of anatomical section sands. Three types of eight gravel, sand, and mudstone phases capable of characterizing diagenetic sands in the Wutonggou Formation were summarized. Based on the lithofacies, four lithofacies assemblage types were further established, representing the point bar, the cross-bank breakout fan, and the fluvial sands, respectively. Through the analysis of the lithofacies combination of the section, the sedimentary subfacies of point bar, crevasse splay, and floodplain in the period of Wutonggou Formation can be further identified, and the sedimentary response model of meandering river with the change of lake level was established. The sedimentary facies and sand body distribution of underground reservoirs were clarified by the results of outcrop research.

In order to solve the technical problem of insufficient reliability and life of rotary seal under the coupling effect of high pressure and high speed and medium corrosion, experimental research on rotary lip seal was carried out, a high-speed rotary lip seal test bed with pressure was designed and built, leakage and friction torque characteristic tests of lip seal were carried out, simulation calculation of lip seal was carried out, and a new type of seal with low friction coating was innovatively proposed. The temperature rise and torque comparison test of traditional seal and spraying new seal at different speeds were carried out. The experimental results show that the lip spraying tetrafluoroethylene (PTFE) material can effectively reduce the temperature rise of the seal. When the rotational speed increases by 1 000 r/min, after reaching the heat balance temperature, the temperature rise of the spray lip seal is 2.4 °C lower than that of the traditional lip seal. Under the pressure condition, the temperature of the coated lip seal is about 3.48 °C lower than that of the traditional lip seal. Under the condition of high speed and poor lubrication, the temperature of the spray lip seal is about 4.61 °C lower than that of the traditional lip seal, but the sealing torque increases by about 0.03 N·m. The sealing performance is evaluated from two aspects of sealing temperature rise and sealing friction torque, which provides theoretical support for solving the technical problems of high parameter rotary seal.

In order to study the effect of polymer microsphere profile control and flooding on produced fluid and deepen the understanding of the profile control and flooding mechanism of polymer microsphere, the produced fluid in typical blocks of major reservoirs such as ultra-low permeablity, super-low permeablity and low permeablity in Changqing oil field were analyzed and studied. After using gravity separation and centrifugal separation methods to obtain crude oil and produced water, the changes in the composition of crude oil group, K⁺, Na⁺, Ca²⁺, Mg²⁺, $\mathrm{SO}_{4}^{2-}$ ions, and water content in the produced water before and after profile control were analyzed, and the variation patterns were summarized. The results show that after injecting polymer microspheres into each typical block, the saturated alkane content in the crude oil decreases, the non-hydrocarbon content increases, the water content significantly decreases, and the salinity of the produced water increases. Through the above research, it has been further clarified that polymer microspheres mainly play a “blocking” role in reservoirs, and residual oil is utilized by expanding the swept volume of injected water, providing a theoretical basis for the production increase of Changqing Oilfield through profile control and flooding.