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Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Current digital office documents involve huge amount of table data. Accordingly, increasing demand on intelligent table recognition emerges. Nonetheless, the table structure is complex and closely linked, leading to the ultrahigh difficulty in table structure detection. To address this problem, a new table row-column cell structure detection method was proposed based on YOLOv8, in which the ICDAR19-cTDaR table cell structure and the TabStructDB table row-column structure were taken as object. Firstly, in order to enhance the extraction of table cells and row and column features, this paper introduced deformable convolution network (DCN). Secondly, the introduction of spatial and channel reconstruction convolution (SCConv) not only had a strong feature extraction capability, but also reduced redundant features to reduce the complexity and computational cost. Based on the above introduced convolution, a new module DSC module was designed to replace the Bottlenck module in C2f and named as C2fDSC module. Additionally, in order to further enhance the corner local feature extraction of the table structure, a explicit visual center feature adjustment (EVC) module was added to the backbone network of YOLOv8. Finally, the loss function of the original model was replaced by MPDIoU. When the problem of dense objective regression accuracy is being solved, the MPDIoU loss function bounding box regression is more accurate and efficient compared to the original model loss function. Experimental results show that the table structure detection algorithm in the dataset ICDAR19-cTDaR achieves the best detection results so far. The cell checking rate, checking rate and F1 value are 91.7%, 82.3% and 86.7%, respectively. Moreover, the proposed algorithm also performed well in the data-set TabStructDB table row and column detection. [ABSTRACT FROM AUTHOR]

In order to study the influence of bimodal pore structure on the mechanical properties of unsaturated soil, two typical bimodal pore structure clays in Nanning and Guilin in Guangxi were selected as target materials and the shear strength characteristics under different saturation conditions were analyzed. The effect mechanism of pore water distribution status on the strength of two kinds of soils with bimodal pore structure was explored by filter paper method and nuclear magnetic resonance (NMR) technique. The results show that the T2 distribution curves of the two samples have bimodal structure under saturated condition. Moreover, on the whole, the water retention characteristics of soil samples show bimodal soil-water characteristic curve. The stress-displacement relationship of the two kinds of soil is similar and the shear strength is closely related to saturation. The change trend of soil sample cohesion changes when the saturation is 40%, while the internal friction angle reaches the minimum at a saturation of 80%. [ABSTRACT FROM AUTHOR]

In order to develop high performance thermal reflective coating for asphalt pavement, this paper studied the effect of the ratio of functional fillers on thermal insulation performance, the effect of the ratio of binder materials on bond strength and the effect of the content of functional fillers on thermal insulation performance and bond strength, and then prepared the thermal reflective coating and evaluated its durability. The results show that, under different mass ratios of TiO2 and SiO2, the thermal insulation performance of the thermal reflective coating increases with the increase of TiO2 mass ratio. Under the same dosage of curing agent, the maximum bond strength is obtained when the dosage of toughening agent is 20%-30%. With the same amount of toughening agent, the maximum bond strength is obtained when the amount of curing agent is 30%-40%. With the increase of the content of functional fillers, the thermal insulation performance of the thermal reflective coating increases, and the bond strength decreases slowly at first and then rapidly. The thermal reflective coating was prepared according to the optimum ratio of each component. The wear rate of the coating increases with the increase of wear times, and the increase rate is fast in the early stage. The thermal insulation performance decreases linearly with the increase of wear rate. With the increase of wear times, the skid resistance first increases rapidly and then decreases slowly. [ABSTRACT FROM AUTHOR]

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Côte d' Ivoire Basin is one of the important oil production areas in Africa. Based on the comprehensive analysis of drilling, logging, and geochemical data in Côte d' Ivoire Basin, this paper comprehensively evaluated the Cretaceous lacustrine source rocks in the study area, established the total organic carbon(TOC) quantitative prediction model of the Cretaceous source rocks in the study area by using the organic carbon method, determined the relationship between seismic reflection characteristics and geochemical characteristics of the source rocks, and tracked the main source rocks horizontally. The results show that the TOC of the Lower Cretaceous Albian source rocks is 2.63%, the kerogen type II is dominant, and the Ro is 0.3%-0. 9%. Source rocks are mainly in the low-mature to mature stage, and generally of good and premium quality. Premium quality source rocks are mainly distributed in the central area of the eastern depression of the basin, TOC values is ranging from 4. 00 % to 5.00 %, thickness is large, and continuity is good. [ABSTRACT FROM AUTHOR]

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to study the effects of temperature and humidity on the performance of proton exchange membrane fuel cell (PEMFC), a temperature and relative humidity-current (TRH-C) model was proposed. The model took the water flow and membrane water content of anode and cathode flow channels into consideration, and revealed the law of current density distribution and membrane water content distribution under the condition of current step change. According to the real flow channel configuration of the experimental single cell, a simplified PEMFC geometric model was established and the calculation grid was divided, and the TRH-C model was coupled to the multi-physical field calculation software COMSOL. A PEMFC test platform was established to test PEMFC under different temperature and humidity conditions. The operating temperatures of PEMFC were 65 °C and 70 °C, and the inlet humidities were 50% and 75%. The polarization curve, the membrane current density, and the membrane water content under different working conditions were analyzed and discussed. The results show that the TRH-C model can accurately predict the output performance of PEMFC. When the operating temperature is 70 °C, the inlet humidity is 50%, and the current density is 0. 018 A/cm², the relative errors of the TRH-C model of voltage and power density both reach the maximum value, which are 7.306% and 8.837%, respectively. The performance of PEMFC can be improved by increasing operating temperature and inlet air humidity. As the operating temperature increases, the distribution uniformity of membrane current density fluctuates and the mem-brane water content decreases. With the increase of inlet air humidity, the film current density distribution becomes more uniform and the film water content increases. This work provides a new theoretical method for optimizing inlet air strategy control and improving the output performance. [ABSTRACT FROM AUTHOR]

In order to study the effects of composite modification by high content rubber powder-SBS on the high-temperature rheological properties of matrix asphalt, the trend of the performance of high content crumb rubber-SBS composite modified asphalt with the change of crumb rubber content was studied firstly by three indexes and Brookfield rotational viscosity. Subsequently, six test schemes were designed and the high temperature rheological properties of six kinds of asphalt were explored by dynamic shear rheometer, based on which a detailed comparative study was carried out. The results show that the high and low temperature performance of high content crumb rubber-SBS composite modified asphalt increases with the increase of crumb rubber content. When the content of crumb rubber is 42%, good performance and satisfaction of construction requirements can be achieved simultaneously. In the high temperature rheological property test, compared with the single modified asphalt, the complex shear modulus (G*), rutting factor (G*/sin(δ)) and creep recovery rate (R) of the matrix asphalt are significantly improved by the composite modification, and the phase angle (δ) and irrecoverable flexibility (Jnr) are reduced. Meanwhile, stronger elastic properties, high temperature rutting resistance, deformation recovery ability, and deformation resistance are obtained. In addition, with the increase of rubber powder content from 21% to 42%, the elastic components of rubber powder-SBS composite modified asphalt also increase, the deformation recovery ability and deformation resistance are stronger, and the high temperature rheological properties are improved. [ABSTRACT FROM AUTHOR]

As a possible countermeasure to the problems such as weak generalization performance and poor robustness in fingerprint localization of extreme learning machine (ELM), an improved differential evolution algorithm was proposed to optimize the finger-print localization method of hybrid kernel extreme learning machine. Specifically, the improved Logistic chaos mapping is used to improve the global search of differential evolution algorithm and the dynamic control parameter method is used to avoid falling into the local optimal. The parameters of hybrid extreme learning machine are adjusted adaptively by the improved differential evolution algorithm to improve the training efficiency. At the online stage, mixed kernel function is used to improve the learning performance and generalization performance of extreme learning machine, and L1 penalty function is introduced to prevent overfitting. Compared with the single core extreme learning machine, its generalization ability improves obviously. The positioning error of 92% test points is less than 0.5m, and the average error is reduced by 32.6% compared with weighted K-nearest neighbor (WKNN). [ABSTRACT FROM AUTHOR]

As a possible countermeasure to the lack in algorithms for solving maximum regularization satisfiability problems as well as inadequate accuracy of intelligent optimization algorithms for solving maximum satisfiability problems, a discrete chaotic quantum based bat algorithm based on the bat algorithm (BA) was proposed herein. This algorithm was discretized by conversion of continuous values to discrete binary codes. By applying quantum theory, introducing quantum bit encoding and heuristic quantum mutation, the mutation is achieved by changing the probability amplitude of non optimal individuals through quantum rotation gates, solving the problems of precocity and slow convergence speed. In position update, chaotic mapping is used to replace fixed parameters, which enhances flexibility and diversity, and improves global optimization ability and solving efficiency. The experimental results show that the proposed algorithm has much higher accuracy than traditional heuristic algorithms in generating different scale examples in the stochastic regularization satisfiability problem instance generation model. At the same time, compared with the award-winning solver, it also has a certain level of competitiveness, verifying the effectiveness of the algorithm. [ABSTRACT FROM AUTHOR]

To study the problems related to two-stage degradation characteristics of locomotive wheels, a two-stage Wiener process-based method for predicting the remaining service life was proposed. The wheel rim degradation model was established by using a two-stage Wiener process model, and the individual differences in the wheel degradation process were characterized by the random drift coefficient. The expectation maximum (EM) algorithm and Bayesian theory were used to achieve offline parameter estimation and online updating of the degradation model parameters. The change point in the wheel degradation process was determined and found via the Schwarz information criterion (SIC). Finally, an example of wheel rim degradation data from a certain locomotive was used for validation. The results show that, compared with the single-stage degradation model, the two-stage degradation model considering the change point is more in line with the field reality, and the prediction accuracy at 80% of the life quantile of the wheel is improved by 9.42%. The prediction of the remaining service life can provide a certain theoretical basis for the optimization of the wheel turning cycle. [ABSTRACT FROM AUTHOR]

In order to clarify the seismic mitigation and isolation performance of sliding friction pendulum bearings of long continuous prestressed concrete (PC) girder bridges in high seismic intensity areas, a nonlinear analysis model of space beam element of a long-unit PC continuous girder bridge with seismic fortification intensity of 9 degrees was established using CSiBridge software. Based on the seismic response of ordinary spherical steel bearing, the seismic isolation performance of lead rubber bearing and sliding friction pendulum bearing was compared and analyzed, and the friction coefficient and bearing curvature of sliding friction pendulum bearing were analyzed. The results show that, compared with the lead rubber bearing, the sliding friction pendulum bearing has better seismic isolation effect, less internal force and deformation of the fixed pier, and more uniform and reasonable force for the long-unit continuous girder bridge. For sliding friction pendulum bearings, the greater the friction coefficient, the greater the bending moment at the bottom of the fixed pier and the displacement at the top of the pier of the long continuous beam. The amplitudes of variation for friction coefficient, maximum bending moment at the bottom of the fixed pier, and the extreme displacement at the top of the pier were found to be 20%, 1.67%, and 1.45%, respectively. The radius of curvature of sliding friction pendulum bearing has little effect on the seismic isolation performance of the long continuous beam. The radius of curvature increases by 1.5 m, the maximum bending moment at the bottom of the fixed pier increases by 0.97%, and the displacement at the top of the fixed pier increases by 0. 37%-1.39%. [ABSTRACT FROM AUTHOR]

To address the problem related to the service life of Butun rock asphalt concrete pavement under different operating conditions, the fatigue damages of Butun rock asphalt concrete, matrix asphalt concrete, and SBS modified asphalt concrete were ana-lyzed under five types of road environments and different frequencies of repetitive loads by three-point bending repetitive loading tests of Butun rock asphalt concrete beam specimens combined with digital image correlation (DIC) technique. The fatigue damage of Butun rock asphalt concrete, matrix asphalt concrete and SBS-modified asphalt concrete in five road environments were analyzed by DIC technique. The results show that the fatigue life under different road environments and multi-frequency is in the order of SBS-modified asphalt concrete>Butun rock asphalt concrete>base asphalt concrete. The fatigue performance of asphalt concrete is improved by the addition of Butun rock, but the sensitivity to the change of vehicle speed is strong. The fatigue cracking resistance of asphalt concrete is enhanced by the addition of Butun rock. The degree of damage same material under the same number of repetitive loading action decreases with the increase in loading frequency. Butun rock admixture can improve the mixture' s resistance to damage and delay the asphalt concrete appeared accelerated cracking time point. Macroscopic cracks appears when the repetitive loads accounted for 70% of the role of the number of times for Butun rock asphalt concrete. The findings herein can be conducive to the developments of appropriate prevention and control measures in advance in practical projects. [ABSTRACT FROM AUTHOR]

To investigate the effect of the infilled wall distribution on the load of progressive collapse resistance of reinforced concrete (RC) frame structures, integral finite element models of RC infilled wall structures were established based on ABAQUS, and the rationality of the modeling method and the selection of the constitutive relation were verified by comparison with experimental results. Furthermore, the load-displacement relationship, the relationship between the horizontal displacement of joints and the vertical displacement of columns, the distribution of plastic hinge and the peak load capacity of RC frame structures with different numbers of infilled walls and distributions were analyzed. The results show that the infilled walls located at the failed column span can sig-nificantly improve the load of progressive collapse resistance of frame structures. The distribution of infilled walls will change the position of plastic hinges of the frame structures. Additionally, the more inhomogeneous the plastic hinge distribution, the weaker the progressive collapse resistance of structures. In architectural design, it is necessary to avoid the horizontal asymmetric distribution of the infilled walls and the situation that the infilled walls are only distributed at both ends of the floor. [ABSTRACT FROM AUTHOR]

In order to quantitatively characterize the porosity of tight cores, the porosity, permeability and pore size distribution of tight cores can be measured by nuclear magnetic resonance (NMR) using the proportional relationship between TT2 relaxation time and pore radius, and the free fluid and bound fluid in pores can be distinguished by TT2 cut-off value. Based on the principle of core porosity characterization by NMR, the relationship between TT2 and core porosity, permeability, pore size distribution and movable fluid in pore is discussed. Through above principles and examples, the accuracy and applicability of the NMR in the quantitative characterization of porosity and permeability of tight cores are verified. The cut-off values and pore size distribution tests of the experimental cores show that the cut-off value of core 1 is 21.85 ms and that of core 2 is 40.11 ms. Core 1 has a large small pore fraction and core 2 has a more uniform pore distribution. The results show that the cut-off values of T2 obtained by regional method are not fully suitable to the case of tight core, and it is necessary to establish a regional version of the cut-off variation range chart. [ABSTRACT FROM AUTHOR]

High-precision 3D seismic is no longer sufficient to meet the current exploration and development needs for complex and concealed small-scale oil reservoir in the Qintong Sag. In 2022, high-density 3D seismic data acquisition was deployed in west Shuaiduo area of Qintong Sag. This 3D seismic used small-bin-size, wide-azimuth, high coverage frequency, high detection point density, and moderate shot point density, based on fine superficial investigations, advantage lithology stimulation and single point broadband receiving technology, high-definition aerial survey images, full node cable free reception, and background noise cable monitoring technology. The sampling density of reflection wave field of complex underground structures was improved, the low-frequency information acquisition was strengthened, and efficient and high-quality construction of high-density seismic were achieved. The resolution, frequency band width, signal-to-noise ratio, deep and interlayer inside reflection data quality of the imaging profile have been greatly improved, with the application of high fidelity surface wave suppression, enhanced resolution process-ing, and full-azimuth migration imaging technology. This 3D seismic exploration has positive reference significance for high-quality seismic exploration of Cenozoic faulted basin with complex surface, eastern China. [ABSTRACT FROM AUTHOR]

In view of the problem of the existing driving index analysis methods, which requires relatively complete bottom pressure detection data and cannot calculate the driving index when the formation pressure history is not clear, this study proposes a new strategy to use partial production performance data to calculate relevant parameters through an improved material balance method, in the case of not shutting down the well and affecting the production, and to calculate the complete average formation pressure history by driving a formula. Then, based on the average formation pressure obtained by this method, the driving energy and driving index could be calculated. Compared with two sets of actual field data, the average relative errors by calculation were 1.28% and 1.07%, respectively, proving the effectiveness of this method. The research results can guide the design and subsequent optimization of oil reservoir development. [ABSTRACT FROM AUTHOR]

In order to study the effects of molding process on the macroscopic performances of cement stabilized gravel, based on two kinds of gradation of skeleton compaction and suspension compaction, eight kinds of cement stabilized gravel were prepared by four kinds of processes: static compaction molding with forced mixing, vibratory compaction with forced mixing, static compaction molding with vibratory mixing, and vibratory compaction with vibratory mixing. Furthermore, the macro-performances of cement stabilized gravel were investigated by adopting the 7 d unconfined compression test, the 28 d single-axis penetration test, the 7 d warming shrinkage test, and the 7 d drying shrinkage test. The underlying microscopic mechanism of the macroscopic property variation of the cement stabilized gravel was analyzed by combining with the microscopic means of scanning electron microscope. The results show that the mechanical properties of cement stabilized gravel with skeleton dense grading under vibration mixing and vibration compaction process are optimal, and its 7 d unconfined compressive strength and 28 d uniaxial compression modulus are improved by 169. 5% and 97. 2%, respectively, compared with that of forced mixing and static compression molding. The vibration mixing vibration compaction techniques can improve the macro performance of cement stabilized crushed stone in terms of promoted the cement hydration product generation, perfect structure, and elevated overall uniformity. [ABSTRACT FROM AUTHOR]

In order to solve the problems of poor volume stability of steel slag and premature cracking of steel slag-asphalt mixture roads, modification via silica colloidal solution immersion of steel slag was carried out. The physical and mechanical properties of modified steel slag, the performance of modified steel slag-asphalt mixture and the modification mechanism of steel slag were investigated through mechanical property test, scanning electron microscope (SEM), road performance test, and the ash target theory decision method was also introduced to synthesize the performance indexes of modified steel slag-asphalt mixture to determine the best modification scheme of steel slag. The results show that the physical and mechanical properties of modified steel slag is significantly improved. The greater the modified concentration of steel slag, the better the high-temperature performance of the asphalt mixture. Extending the modification time of steel slag improves the low-temperature crack resistance of the asphalt mixture, and the water stability of the asphalt mixture is significantly improved after the modification of steel slag. Based on the gray target decision theory, the best modification solution for steel slag is finally determined to be a 24 h immersion in a solution with a modification concentration of 3%. [ABSTRACT FROM AUTHOR]