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3-D Tunnel Seismic Advance Prediction Method with Wide Illumination and High-Precision

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Journal of Earth Science 2024年第3期35卷 970-979页

作者： Peng guan Cuifa Shao Yuyong Jiao Guohua Zhang Junpeng Zou Fei Tan Faculty of Engineering China University of GeosciencesWuhan 430074China

Tunnel seismic advance prediction can effectively reduce the construction risk during tunnel *** with the 2-D method,the 3-D method is more conducive to describing the spatial characteristics of the geological body by adding the seismic data in the vertical ***,some drawbacks still need improvement in the current 3-D tunnel seismic prediction method.(1)The geometry is complex,which is destructiveness,high cost,and time-consuming,and will delay the tunnel construction schedule.(2)Illumination of the anomalous body is insufficient,and the precision of migration imaging is low.(3)Shot points are far away from the tunnel face,the energy loss at the shot points is more serious.(4)The received signals at the tunnel wall have the surface wave with strong energy when the shot points are placed on the tunnel wall.(5)The geometry is not linear,so the directional filtering method cannot be used to extract the reflection *** overcome the drawbacks of the current prediction method,a new 3-D symmetrical tunnel seismic prediction method is *** geophones are installed on the tunnel wall,two on the left side,two on the right side,and two on the top ***-four shot points are placed on the tunnel face and near both sides of the tunnel wall,twelve shot points on the left side and twelve shot points on the right *** shot points will move along with the forward excavation of the *** wavefield analysis,illumination statistics,and 3-D reverse time migration imaging are used to evaluate the proposed *** result of modeled data indicates that the proposed 3-D geometry has some advantages:(1)the geometry is simple and the geophone installation time is short;(2)it has high illumination energy,wide illumination range,and can improve the prediction distance and imaging accuracy;(3)the proposed 3-D method can better estimate the velocity of surrounding rock and is more conducive to extracting the reflection wave with high resolut

关键词： tunnels excavation geophone shot points migration imaging method engineering ge-ology.

Multi-scale data joint inversion of minerals and porosity in altered igneous reservoirs—A case study in the South China Sea

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Petroleum Science 2024年第1期21卷 206-220页

作者： Xin-Ru Wang Bao-Zhi Pan Yu-Hang Guo Qing-Hui Wang Yao guan College of Geo-exploration Science and Technology Jilin UniversityChangchun130046JilinChina Research Institute CNOOC Ltd.-ShenzhenShenzhen518000GuangdongChina

There are abundant igneous gas reservoirs in the South China Sea with significant value of research,and lithology classification,mineral analysis and porosity inversion are important links in reservoir ***,affected by the diverse lithology,complicated mineral and widespread alteration,conventional logging lithology classification and mineral inversion become considerably *** the same time,owing to the limitation of the wireline log response equation,the quantity and accuracy of minerals can hardly meet the exploration requirements of igneous *** overcome those issues,this study takes the South China Sea as an example,and combines multi-scale data such as micro rock slices,petrophysical experiments,wireline log and element cutting log to establish a set of joint inversion methods for minerals and porosity of altered igneous ***,we define the lithology and mineral characteristics through core slices and mineral data,and establish an igneous multi-mineral volumetric *** we determine element cutting log correction method based on core element data,and combine wireline log and corrected element cutting log to perform the lithology classification and joint inversion of minerals and ***,it is always difficult to determine the elemental eigenvalues of different minerals in *** paper uses multiple linear regression methods to solve this ***,an integrated inversion technique for altered igneous formations was *** results show that the corrected element cutting log are in good agreement with the core element data,and the mineral and porosity results obtained from the joint inversion based on the wireline log and corrected element cutting log are also in good agreement with the core data from X-ray *** results demonstrate that the inversion technique is applicable and this study provides a new direction for the mineral inversion research of altered igneous formation

关键词： Joint inversion Altered igneous rock Element correction method Lithology identification Multi mineral volume model

A method to determine the bonded-particle model parameters for simulation of ores

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Particuology 2024年第3期86卷 24-38页

作者： Shuwei Wu Guoqiang Wang Longfei Fan Wei guan Jianbo Guo Zhengbin Liu Yukuan Wang School of Mechanical and Aerospace Engineering Jilin UniversityChangchun130025China

The bonded-particle model(BPM)is commonly used in the numerical analysis of ore *** improve the accuracy of simulating the mechanical process of ore process of ore crushing in a crusher,the parameters of the BPM for the ore must be *** this study,a calibration method was proposed for the scientific determination of the parameters of the BPM for ore undergoing uniaxial ***,physical tests and simulations were conducted to determine the mechanical response(uniaxial compressive strength and macroscopic stiffness)of ore during uniaxial ***,the sensitivity of the mechanical response to the values of microscopic parameters was tested using a Plackett-Burman ***,the microscopic parameters with the greatest impact on the response were identified,and the range of parameters that met the target response was determined using a steepest ascent design;Second,a second-order model of the mechanical response was established using the sensitive parameters by combining a Box-Behnken design with response surface methodology to obtain the optimal BPM *** tests showed that the normal stiffness per unit area,critical shear stress,and bonded disk radius had significant effects on the uniaxial compressive strength(UCS)and macroscopic stiffness(MS).To verify the validity of the proposed calibration method,laboratory tests were *** consistency of the simulation results with experimental results indicated that response surface methodology with the Plackett-Burman design,steepest ascent design,and Box-Behnken design can be an effective method for calibrating the BPM of ores.

关键词： Bonded-particle model Discrete element method Calibration method Design of experiment Uniaxial compression test

AstroPose:Astronaut pose estimation using a monocular camera during extravehicular activities

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Science China(Technological Sciences) 2024年第6期67卷 1933-1945页

作者： LIU ZiBin LI You WANG ChunHui LIU Liang guan BangLei SHANG Yang YU QiFeng College of Aerospace Science and Engineering National University of Defense TechnologyChangsha410073China Key Laboratory of Human Factors Engineering China Astronaut Research and Training CenterBeijing100094China

With the completion of the Chinese space station,an increasing number of extravehicular activities will be executed by astronauts,which is regarded as one of the most dangerous activities in human space *** guarantee the safety of astronauts and the successful accomplishment of missions,it is vital to determine the pose of astronauts during extravehicular *** article presents a monocular vision-based pose estimation method of astronauts during extravehicular activities,making full use of the available observation ***,the camera is calibrated using objects of known structures,such as the spacesuit backpack or the circular handrail outside the space ***,the pose estimation is performed utilizing the feature points on the *** proposed methods are validated both on synthetic and semi-physical simulation experiments,demonstrating the high precision of the camera calibration and pose *** further evaluate the performance of the methods in real-world scenarios,we utilize image sequences of Shenzhou-13 astronauts during extravehicular *** experiments validate that camera calibration and pose estimation can be accomplished solely with the existing observation resources,without requiring additional complicated *** motion parameters of astronauts lay the technological foundation for subsequent applications such as mechanical analysis,task planning,and ground training of astronauts.

关键词： monocular camera astronaut pose estimation camera calibration

Effect of slag composition on kinetic behavior of deep deoxidation of 5 wt.% Si high-silicon austenitic stainless steel

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Journal of Iron and Steel Research International 2024年第8期31卷 1873-1885页

作者： guan-xiong Dou Han-jie Guo Jing Guo Xue-cheng Peng Qing-yun Chen School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing 100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing 100083China

Based on a thermodynamic study of 5 wt.%Si high-silicon austenitic stainless steel(SS-5Si)smelting using CaF_(2)-CaO-Al_(2)0_(3)-Mg-Si0_(2) slag to obtain a low oxygen content of less than 10×10^(-4) wt.%,a kinetic mass transfer model for deep deoxidation was established through laboratory studies,and the effects of slag components and temperature on deoxidation during the slag-steel reaction process of sS-5Si were systematically *** experimental data verified the accuracy of the model *** results showed that the final oxygen content in the steel at 1873 K was mainly controlled by the oxygen content derived from the activity of SiO_(2) regulated by the[Si]-[O]equilibrium reaction in the slag system;in particular,when the slag basicity R(R=w(CaO)/w(SiO2),where w(CaO)and w(SiO_(2))are the contents of CaO and SiO_(2) in the slag,respectively)is 3,the Al2O3 content in the slag needs to be less than 2.7%.The mass transfer rate equation for the kinetics of the deoxidation reaction revealed that the mass transfer of oxygen in the liquid metal is the rate-controlling step under different slag conditions at 1873 K,and the oxygen transfer coefficient ko.m increases with increasing the slag basicity from 4.0×10^(-6)m s^(-1)(R=1)to 4.3×10^(-5) m s^(-1)(R=3).ko.m values at R=2 and R=3 are almost the same,indicating that high slag basicity has little *** integral of the mass transfer rate equation for the deoxidation reaction of SS-5Si under different slag conditions is *** total oxygen content of the molten steel decreases with increasing basicity from an initial content of 22×10^(-4) to 3.2×10^(-4) wt.%(R=3),consistent with the change in ko.m with slag *** R=2,the slag-steel reaction takes 15 min to reach equilibrium(w[O]=5.5×10^(-4) wt.%),whereas at R=3,the slag-steel reaction takes 30 min to reach equilibrium(w[0]=3.2×10^(-4) wt.%).Considering the depth of deoxidation and reaction time of SS-5Si smelting,it is recommended the slag b

关键词： Slag-steel reaction Kinetics Rate-controlling step Deep deoxidation Transfer coefficient

Emulsifying property,antioxidant activity,and bitterness of soybean protein isolate hydrolysate obtained by Corolase PP under high hydrostatic pressure

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Food Science and Human Wellness 2024年第3期13卷 1271-1278页

作者： Haining guan Chunmei Feng Min Ren Xiaojun Xu Dengyong Liu Xiaoqin Diao College of Food Science and Technology Bohai UniversityJinzhou 121013China

Enzymatic hydrolysis of proteins can enhance their emulsifying properties and antioxidant ***,the problem related to the hydrolysis of proteins was the generation of the bitter ***,high hydrostatic pressure(HHP)treatment has attracted much interest and has been used in several studies on protein ***,the study aimed to investigate the effects of enzymatic hydrolysis by Corolase PP under different pressure treatments(0.1,100,200,and 300 MPa for 1-5 h at 50℃)on the emulsifying property,antioxidant activity,and bitterness of soybean protein isolate hydrolysate(SPIH).As observed,the hydrolysate obtained at 200 MPa for 4 h had the highest emulsifying activity index(47.49 m^(2)/g)and emulsifying stability index(92.98%),and it had higher antioxidant activities(44.77%DPPH free radical scavenging activity,31.12%superoxide anion radical scavenging activity,and 61.50%copper ion chelating activity).At the same time,the enhancement of emulsion stability was related to the increase of zeta potential and the decrease of mean particle *** addition,the hydrolysate obtained at 200 MPa for 4 h had a lower bitterness value and showed better *** study has a broad application prospect in developing food ingredients and healthy foods.

关键词： Soybean protein isolate High hydrostatic pressure Emulsification Antioxidant Bitter taste

Free-moving-state microscopic imaging of cerebral oxygenation and hemodynamics with a photoacoustic fiberscope

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Light(Science & Applications) 2024年第1期13卷 33-46页

作者： Xiaoxuan Zhong Yizhi Liang Xiaoyu Wang Haoying Lan Xue Bai Long Jin Bai-Ou guan guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications Institute of Photonics TechnologyJinan UniversityGuangzhou510632China

We report the development of a head-mounted photoacoustic fiberscope for cerebral imaging in a freely behaving *** 4.5-gram imaging probe has a 9-µm lateral resolution and 0.2-Hz frame rate over a 1.2-mm wide *** probe can continuously monitor cerebral oxygenation and hemodynamic responses at single-vessel resolution,showing significantly different cerebrovascular responses to external stimuli under anesthesia and in the freely moving *** example,when subjected to high-concentration CO_(2) respiration,enhanced oxygenation to compensate for hypercapnia can be visualized due to cerebral regulation in the freely moving *** studies exhibit significantly weakened compensation capabilities in obese *** new imaging modality can be used for investigating both normal and pathological cerebrovascular functions and shows great promise for studying cerebral activity,disorders and their treatments.

关键词： cerebral anesthesia moving

Causal role of immune cells in obstructive sleep apnea hypopnea syndrome:Mendelian randomization study

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World Journal of Clinical Cases 2024年第7期12卷 1227-1234页

作者： Huang-Hong Zhao Zhen Ma Dong-Sheng guan Department of Encephalopathy Henan Provincial Hospital of Traditional Chinese MedicineZhengzhou 450000Henan ProvinceChina Department of Personnel The First Affiliated Hospital of Henan University of Traditional Chinese MedicineZhengzhou 450000Henan ProvinceChina Department of Neurology Henan Provincial Hospital of Traditional Chinese MedicineZhengzhou 450000Henan ProvinceChina

BACKGROUND Despite being one of the most prevalent sleep disorders,obstructive sleep apnea hypoventilation syndrome(OSAHS)has limited information on its immunologic *** immunological underpinnings of certain major psychiatric diseases have been uncovered in recent years thanks to the extensive use of genome-wide association studies(GWAS)and genotyping techniques using highdensity genetic markers(e.g.,SNP or CNVs).But this tactic hasn't yet been applied to *** a Mendelian randomization analysis,we analyzed the causal link between immune cells and the illness in order to comprehend the immunological bases of *** To investigate the immune cells'association with OSAHS via genetic methods,guiding future clinical *** A comprehensive two-sample mendelian randomization study was conducted to investigate the causal relationship between immune cell characteristics and *** statistics for each immune cell feature were obtained from the GWAS *** on 731 immune cell properties,such as morphologic parameters,median fluorescence intensity,absolute cellular,and relative cellular,was compiled using publicly available genetic *** results'robustness,heterogeneity,and horizontal pleiotropy were confirmed using extensive sensitivity *** Following false discovery rate(FDR)correction,no statistically significant effect of OSAHS on immunophenotypes was ***,two lymphocyte subsets were found to have a significant association with the risk of OSAHS:Basophil%CD33dim HLA DR-CD66b-(OR=1.03,95%CI=1.01-1.03,P<0.001);CD38 on IgD+CD24-B cell(OR=1.04,95%CI=1.02-1.04,P=0.019).CONCLUSION This study shows a strong link between immune cells and OSAHS through a gene approach,thus offering direction for potential future medical research.

关键词： Obstructive sleep apnea hypopnea syndrome Immunity Causal inference MR analysis Sensitivity

Automated and controlled patch generation for enhanced fixing of communication software vulnerabilities

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Intelligent and Converged Networks 2024年第3期5卷 222-236页

作者： Shuo Feng Shuai Yuan Zhitao guan Xiaojiang Du School of Control and Computer Engineering North China Electric Power UniversityBeijing 100029China Department of Finance Operationsand Information SystemsBrock UniversitySt.Catharines L2S3A1Canada Department of Electrical and Computer Engineering Stevens Institute of TechnologyHobokenNJ 07030USA

Software is a crucial component in the communication systems,and its security is of paramount ***,it is susceptible to different types of attacks due to potential ***,significant time and effort is required to fix such *** propose an automated program repair method based on controlled text generation ***,we utilize a fine-tuned language model for patch generation and introduce a discriminator to evaluate the generation process,selecting results that contribute most to vulnerability ***,we perform static syntax analysis to expedite the patch verification *** effectiveness of the proposed approach is validated using QuixBugs and Defects4J datasets,demonstrating significant improvements in generating correct patches compared to other existing methods.

关键词： automatic program repair controlled text generation communication software security program language model