With the improvement of intelligence, the drilling industry ’s demand for real-time identification of lithology while drilling was becoming more and more urgent. An intelligent inversion method of lithology while drilling is proposed based on the acoustic signal and vibration signal ( acoustic vibration signal ) of broken rock during drilling. Firstly, the original signal samples were obtained by drilling seven different types of rocks through indoor micro-drilling experiments. During the acquisition process, the drilling parameters ( drilling speed, rotation speed, bit size ) were changed and the corresponding signal data were obtained. According to the characteristics of the collected acoustic vibration signal, the time-frequency image with signal characteristics was obtained by short-time Fourier transform. On this basis, an improved VGG16 convolutional neural network model was constructed to realize the intelligent identification of lithology, and the training, evaluation and tuning of the model are realized by hyperparameter optimization. Then, the transfer learning training strategy is introduced, and different drilling parameters were used as data labels. According to the parameter values, the source domain and the target domain were divided to realize the rapid identification of the small sample target domain. The experimental results show that the transfer learning results of the model are different with the change of drilling parameters. The lithology inversion model based on acoustic-vibration signal training has high prediction accuracy and strong generalization ability. The accuracy of the acoustic signal test set is up to 99%, and the accuracy of the vibration signal test set is up to 100%. Under the change of penetration rate, the acoustic and vibration signals are least affected, which can achieve more excellent results when used as data labels for lithology inversion, and the accuracy of lithology inversion is the highest when the penetration rate is small as the target domain. In the process of lithology inversion, different signal types are suitable for different rocks. Among them, the sound signal has the highest applicability to coarse yellow sandstone, and the vibration signal is more suitable for granite. The research results have certain reference value for improving the intelligent degree of working face drilling.

To explore the application regularity and mechanism of formulas containing Huang Qin (Scutellariae radix)-Bai Zhu (Atractylodis macrocephalae Rhizoma) (HQ-BZ) herb pair in the treatment of ICP (intrahepatic cholestasis of pregnancy). All literature on prescriptions containing HQ-BZ herb pairs against ICP was screened from the VIP, Wanfang, and CNKI databases. Subsequently, the R language was employed to analyze and summarize its medication rules and core prescriptions. Network pharmacology was used to predict the mechanism of core prescriptions against ICP, followed by molecular docking and experimental verification to confirm the potential mechanism. A total of 68 prescriptions were included, involving 67 herbs characterized mainly by cold, bitter, and spleen meridian. The core prescription “Artemisiae scopariae Herba-Rhei radix et Rhizoma-Gardeniae fructus-Scutellariae radix-Atractylodis macrocephalae Rhizoma-Poriacocos” was obtained based on the comprehensive analysis of traditional Chinese medicine data, among which quercetin, apigenin, and other key active components may act on core targets such as AKT1 (serine/threonine kinase B1), BAX (BCL2-associated X protein), and participate in PI3K-AKT (phosphatidylinositol 3-kinase/protein kinase B), apoptosis, and other multiple targets and pathways to play the role of ICP therapy. The molecular docking results showed that apigenin demonstrated superior binding affinity with the top 11 core targets compared to quercetin and beta-sitosterol. HTR-8/SVneo cell experiments proved that apigenin significantly reduced the apoptosis rate induced by TCA (taurocholic acid) and elevated the protein expression levels of Bax/Bcl-2 (P<0.01), as well as p-PI3K/PI3K, and p-AKT/AKT (P<0.01). Pre-treatment with LY294002 could reverse the anti-apoptosis effects and the expression levels of the aforementioned proteins induced by apigenin. In summary, the core prescription that includes the HQ-BZ can provide references for the clinical prescription of ICP. Apigenin, a key component of core prescription, can inhibit the apoptosis in HTR-8/SVneo cells induced by TCA and has the potential to treat ICP, and its mechanism may be related to the regulation of the PI3K-AKT signaling pathway.

The degradation of mechanical properties of PE pipe materials caused by hot oxygen aging will inevitably reduce the service life of the pipe, which is a serious hidden danger to social and economic development and people’s life and property safety. A nonlinear ultrasonic evaluation method for thermo-oxygen aging pipes was proposed. The nonlinear ultrasonic detection signals of PE pipes were extracted by building a nonlinear ultrasonic detection system for water immersion, and a correlation model between the characteristic parameters of nonlinear ultrasonic detection and elongation at break and fracture stress was established. The nonlinear ultrasonic detection mechanism was revealed by observing the micro-structure changes of PE pipes after aging. The experimental results show that the elongation at break and profit at break of PE pipe materials decrease with the increase of the nonlinear coefficient. The surface micro-cracks, holes and folds formed after the aging of the pipe are the main reasons for the mechanical degradation of the pipe and the increase of the nonlinear ultrasonic detection coefficient. The nonlinear coefficient can be used to evaluate the mechanical degradation of the pipe caused by thermal oxygen aging.

To address the reduction in support bearing capacity caused by concrete shrinkage and to improve the damping performance of supports under mining-induced seismic conditions, this study focuses on the energy-absorbing and shock-resisting performance of single arch sand-filled steel tubular frames and the damping performance of multi-arch combined support systems. Finite element software was employed to establish models of surrounding rock and sand-filled steel tubular frames, as well as multi-arch support systems connected with flexible cables and dampers. The performance of sand-filled steel tubular frames under static and dynamic loading, as well as their seismic resistance under mining-induced tremors, was investigated. The results indicate that the deformation of the tunnel under static loading remains stable, while the support effectiveness is satisfactory under impact loading except for relatively large deformations at the crown. Under static and dynamic loading, the equivalent plastic strain at the crown of the sand-filled steel tubular frames shows a significant increase, while changes in other areas remain minimal, demonstrating good load-bearing capacity. In the three-arch support system, the third arch experiences reduced vibration amplitude due to the dual energy dissipation effects of flexible cables and dampers. Calculations of the safety factor at the maximum shear stress of the tunnel reveal a significant improvement in the seismic performance of adjacent supports, providing insights for further studies on support damping mechanisms.

In view of the problem of limited pressure relief and anti-impact ability of large diameter boreholes in high stress and strong disturbance coal seams. The methods of theoretical analysis, numerical simulation and field test were adopted to study the mechanism of pressure relief and anti-impact of large diameter boreholes, and the control measures of pressure relief and anti-impact of large diameter boreholes were proposed to improve the pressure relief and anti-impact performance of high stress and strong disturbance coal seams. The results show that the pressure relief range of large diameter boreholes is directly proportional to the drilling radius, surrounding rock stress, and disturbance stress increment, and inversely proportional to the constraint force of the fracture zone and plastic zone. Increasing the pressure relief range of large diameter boreholes can increase the attenuation of dynamic stress wave energy, transfer static load energy to the deep surrounding rock, and reduce the risk of coal seam rockburst. As the disturbance coefficient increases, the range of pressure relief for large diameter boreholes and the gathering elastic energy around the boreholes show an increasing trend. The vibration acceleration of borehole increases exponentially with the increase of disturbance coefficient and shock energy. When the disturbance coefficient is greater than 2, the impact dynamic load is superimposed, and the large diameter borehole is blocked to achieve the ultimate anti-impact ability. The use of dense drilling method and repeated drilling method can increase the pressure relief range of large diameter drilling, reduce the risk of coal seam rockburst. After field test, the deformation of surrounding rock of roadway is reduced by 31.5%~67.0%, the stress value of coal body is lower than the critical warning value, and the stability of surrounding rock of roadway is significantly improved.

The variation law of C₄AF and C₃A corrosion products and the formation rate coefficient of CaCO₃ of cement single ore were quantitatively analyzed by SEM, XRD and TG analysis and test methods. The experimental results showed that both C₄AF and C₃A produced a large number of flocculent phases after CO₂ corrosion, but C₃A produced more lumpy and flocculent phases after corrosion than C₄AF corrosion. The relative crystallinity of C₃AH₆ decreases and the relative crystallinity of aragonite increases in the later stage of corrosion reaction, and the quantitative analysis results show that the content of CaCO₃ in C₄AF is higher than that of C₃A, and the molar formation rate of CaCO₃ in C₄AF is 28.36 mol/d and that of C₃A sample is only 4.23 mol/d after 1 day of corrosion reaction. With the extension of the corrosion reaction time to 28 days, the molar formation rate of corrosion products of C₄AF and C₃A continued to decrease, which was 1.83 mol/d and 1.48 mol/d, respectively. The coefficient of corrosion product formation α rate of C₄AF was 32.62 after fitting, which was much higher than that of C₃A single ore (2.74). The corrosion resistance of C₃A ore in CCUS environment is stronger than that of C₄AF, which not only provides theoretical guidance for the development of high performance cement materials resistant to CO₂ corrosion, but also provides a basis for the application of cement in CCUS environment.

Due to the complex reservoir conditions and multi-scale pore structure of shale gas, the production shows significant nonlinear characteristics over time. Traditional production prediction methods, which rely on statistical analysis of geological and engineering data, find it difficult to adapt to the complexity of geological conditions and thus cannot achieve high accuracy. A method that combines the hyperbolic decline model with a composite function having time attributes was proposed. The improved A-PSO (adaptive particle swarm optimization algorithm) was used to find the optimal model parameters, establishing a composite time hyperbolic decline model. The research results show as follows. The A-PSO optimization algorithm can automatically adjust parameters and model structure according to the complexity of production data and data changes, finding the optimal parameter combination more quickly and accurately, thereby improving prediction accuracy. The production fluctuates greatly over time, making it difficult for conventional decline models to reflect its characteristics. The composite time decline model, with its strong flexibility, can consider the complexity and variability of oil and gas reservoirs, more accurately describe the production changes of shale gas wells at different stages, and provide higher fitting accuracy, making the production prediction closer to the actual value.

In order to analyze the design parameters and technology adaptability of multi-stage temporary plugging and fracturing in the Triassic Chang-6 reservoir of a block in Suijing Oilfield. Based on the geological and engineering design data of the block, the influencing factors of multi-stage temporary plugging and fracturing were quantitatively analyzed in terms of reservoir characteristics, technology parameters, and construction effect. The combined weighting method was used to determine the weights of each parameter, and the ridge-type membership function was used to determine the membership degree of each factor. Based on the principles of fuzzy transformation and maximum membership degree, a fuzzy comprehensive evaluation model for multi-stage temporary plugging and fracturing was established. This model transforms the traditional single-index qualitative development effect evaluation into multi-factor quantitative evaluation. The model was applied to evaluate and analyze the Triassic Chang-6 reservoir in a block of Suijing Oilfield. The results show that this evaluation model results have an adaptation rate of 89.13% when compared to the actual effect data in the field, which can effectively evaluate the effectiveness of the implementation of temporary plugging and fracturing measures in the oil wells of the study area. The evaluation system can provide valuable references for the next implementation of temporary plugging and fracturing measures in the study area, and even optimize parameters for multi-stage temporary plugging and fracturing transformation in similar reservoirs.

The length of the impactor is generally about one meter according to the current application of all kinds of impactors.As the existing impactor increases the distance between the stabilizer and the drill bit, it will cause the theoretical build slope and the lateral force of the drill bit to decrease when it is used in connection with the drill bit. This will in turn affects the drilling deviation section.In this regard, the multi-dimensional impactor with built-in drill bit can effectively solve this problem.Firstly, in order to maximize the performance of the multi-dimensional impactor with built-in drill bit and reduce the pressure loss, the PB (Plackett-Burman) screening test design was adopted to conduct screening tests on the internal parameters of the impactor. The effect of each parameter on the tool performance was as follows: Jet channel width > inlet area > Outlet area > length of oscillating cavity > width of double feedback channel > curvature radius of wall attached surface > wedge Angle. Then, BBD (Box-Behnken design) response surface method was used to provide an in-depth analysis of the top three significant impact parameters.The optimized combination of the internal structure of the multi-dimensional impacter with built-in drill bit was obtained as follows: the inlet area is 1 203.416 mm², the jet channel width is 14 mm, and the outlet area is 455 mm². Finally, the effectiveness of the optimization method was verified by the simulation of Fluent software, which met the design requirements.

In traditional blind deconvolution algorithms, recalculating the gradient or redesigning the optimization approach for filter coefficients becomes necessary when altering the characterization index. This requirement can render the development process of new blind deconvolution algorithms inflexible. To address these issues, a blind deconvolution algorithm that employs NRO(Newton-Raphson optimizer) to seek out the optimal filter coefficients was proposed. Initially, generalized spherical coordinate transformation was used to define the search range for the filter coefficients. Subsequently, the generalized l_p/l_q norm of the envelope spectrum was adopted as the characterization index. The proposed blind deconvolution algorithm is then utilized for the early detection of minor faults in rolling bearings. Both simulation and experimental results confirm the efficacy of the proposed algorithm, demonstrating its faster convergence rate compared to classical PSO(particle swarm optimization).