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Evolution of mechanical parameters of Shuangjiangkou granite under different loading cycles and stress paths

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1113-1126页

作者： Liangjie Gu xia-ting feng Rui Kong Chengxiang Yang Yuelin xia Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang110819China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China

Surrounding rocks at different locations are generally subjected to different stress paths during the process of deep hard rock *** this study,to reveal the mechanical parameters of deep surrounding rock under different stress paths,a new cyclic loading and unloading test method for controlled true triaxial loading and unloading and principal stress direction interchange was proposed,and the evolution of mechanical parameters of Shuangjiangkou granite under different stress paths was studied,including the deformation modulus,elastic deformation increment ratios,fracture degree,cohesion and internal friction ***,stress path coefficient was defined to characterize different stress paths,and the functional relationships among the stress path coefficient,rock fracture degree difference coefficient,cohesion and internal friction angle were *** results show that during the true triaxial cyclic loading and unloading process,the deformation modulus and cohesion gradually decrease,while the internal friction angle gradually increases with increasing equivalent crack *** stress path coefficient is exponentially related to the rock fracture degree difference *** the stress path coefficient increases,the degrees of cohesion weakening and internal friction angle strengthening decrease *** cyclic loading and unloading under true triaxial principal stress direction interchange,the direction of crack development changes,and the deformation modulus increases,while the cohesion and internal friction angle decrease slightly,indicating that the principal stress direction interchange has a strengthening effect on the surrounding ***,the influences of the principal stress interchange direction on the stabilities of deep engineering excavation projects are discussed.

关键词： Triaxial cyclic loading and unloading test Stress path Deformation modulus and elastic deformation increment ratios Fracture degree Cohesion and internal friction angle

Development of high-power microwave mechanical integrated continuous mining device

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3365-3377页

作者： xia-ting feng feng Lin Jiuyu Zhang Chengxiang Yang Yuntan Ao Tianyang Tong Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang110819China Key Laboratory of Liaoning Province on Deep Engineering and Intelligent Technology Northeastern UniversityShenyang110819China

This article introduces a high-power microwave mechanical integrated continuous mining device,which can achieve synchronous cutting of hard rocks by microwave and *** device includes a cutting system,a rotary translation system,a loading system,a high-power microwave system,and a control and monitoring *** technology of“master-slave follow-up”disc cutter alternating side cutting of rock was proposed,which could improve the effectiveness of rock *** integrated structure of a microwave-cut system was then proposed,and synchronous motion of the microwave-cut system and adjustment of the loading system could be *** automatic adjustment technology of the microwave working distance was developed to dynamically control the optimal microwave working *** basic functions of the equipment were verified by *** comparing the two types of disk cutters,it is found that the master-slave follow-up disk cutter can improve significantly the dust removal effect and rock breaking efficiency in rock breaking process versus the conventional large disc *** tests of slate with or without microwave were conducted using a master-slave follow-up disk *** results show that the cutting patterns of slates change from intermittent chunks(without microwave irradiation)to persistent debris(with microwave irradiation),and the cutting speed is significantly improved(170%).The development of the device provides a scientific basis for changing the conventional mining technology of metal mines and realizing the mechanical continuous mining in hard metal mines.

关键词： Hard metal mine Microwave machinery Continuous mining Master-slave follow-up disc cutter

An improved deep dilated convolutional neural network for seismic facies interpretation

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Petroleum Science 2024年第3期21卷 1569-1583页

作者： Na-xia Yang Guo-Fa Li ting-Hui Li Dong-feng Zhao Wei-Wei Gu State Key Laboratory of Petroleum Resources and Engineering CNPC Key Lab of Geophysical ExplorationChina University of Petroleum(Beijing)Beijing 102249China Dagang Branch Research InstituteBGPTianjin300280China

With the successful application and breakthrough of deep learning technology in image segmentation,there has been continuous development in the field of seismic facies interpretation using convolutional neural *** intelligent and automated methods significantly reduce manual labor,particularly in the laborious task of manually labeling seismic ***,the extensive demand for training data imposes limitations on their wider *** overcome this challenge,we adopt the UNet architecture as the foundational network structure for seismic facies classification,which has demonstrated effective segmentation results even with small-sample training ***,we integrate spatial pyramid pooling and dilated convolution modules into the network architecture to enhance the perception of spatial information across a broader *** seismic facies classification test on the public data from the F3 block verifies the superior performance of our proposed improved network structure in delineating seismic facies *** analysis against the traditional UNet model reveals that our method achieves more accurate predictive classification results,as evidenced by various evaluation metrics for image ***,the classification accuracy reaches an impressive 96%.Furthermore,the results of seismic facies classification in the seismic slice dimension provide further confirmation of the superior performance of our proposed method,which accurately defines the range of different seismic *** approach holds significant potential for analyzing geological patterns and extracting valuable depositional information.

关键词： Seismic facies interpretation Dilated convolution Spatial pyramid pooling Internal feature maps Compound loss function

A multifunctional shear apparatus for rocks subjected to true triaxial stress and high temperature in real-time

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3524-3543页

作者： Jun Zhao xia-ting feng Jia-Rong Wang Liang Hu Yue Guo Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang110819China Key Laboratory of Liaoning Province on Deep Engineering and Intelligent Technology Northeastern UniversityShenyang110819China

Deep engineering disasters,such as rockbursts and collapses,are more related to the shear slip of rock joints.A novel multifunctional device was developed to study the shear failure mechanism in *** this device,the complete shearedeformation process and long-term shear creep tests could be performed on rocks under constant normal stiffness(CNS)or constant normal loading(CNL)conditions in real-time at high temperature and true-triaxial *** the research and development process,five key technologies were successfully broken through:(1)the ability to perform true-triaxial compressioneshear loading tests on rock samples with high stiffness;(2)a shear box with ultra-low friction throughout the entire stress space of the rock sample during loading;(3)a control system capable of maintaining high stress for a long time and responding rapidly to the brittle fracture of a rock sample as well;(4)a refined ability to measure the volumetric deformation of rock samples subjected to true triaxial shearing;and(5)a heating system capable of maintaining uniform heating of the rock sample over a long *** developing these technologies,loading under high true triaxial stress conditions was *** apparatus has a maximum normal stiffness of 1000 GPa/m and a maximum operating temperature of 300*** differences in the surface temperature of the sample are constant to within5*** types of true triaxial shear tests were conducted on homogeneous sandstone to verify that the apparatus has good performance and *** results show that temperature,lateral stress,normal stress and time influence the shear deformation,failure mode and strength of the *** novel apparatus can be reliably used to conduct true-triaxial shear tests on rocks subjected to high temperatures and stress.

关键词： True-triaxial shear apparatus Rocks Complete shear stressedeformation process Creep Real-time high-temperature

Field test of high-power microwave-assisted mechanical excavation for deep hard iron ore

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 1922-1935页

作者： feng Lin xia-ting feng Shiping Li xiao Hai Jiuyu Zhang xiangxin Su Tianyang Tong Jianchun Song Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang110819China Benxi Longxin Mining Corporation Limited Benxi117000China

Microwave-assisted mechanical excavation has great application prospects in mines and tunnels,but there are few field experiments on microwave-assisted rock *** paper takes the Sishanling iron mine as the research object and adopts the self-developed high-power microwave-induced fracturing test system for hard rock to conduct field experiments of microwave-induced fracturing of iron *** heating and reflection evolution characteristics of ore under different microwave parameters(antenna type,power,and working distance)were studied,and the optimal microwave parameters were ***,the ore was irradiated with the optimal microwave parameters,and the cracking effect of the ore under the action of the high-power open microwave was *** results show that the reflection coefficient(standing wave ratio)can be rapidly(<5 s)and automatically adjusted below the preset threshold value(1.6)as microwave irradiation is *** using a right-angle horn antenna with a working distance of 5 cm,the effect of automatic reflection adjustment reaches the best among other antenna types and working *** the working distance is the same,the average temperature of the irradiation surface and the area of the high-temperature area under the action of the two antennas(right-angled and equal-angled horn antenna)are basically the same and decrease with the increase of working *** optimal microwave parameters are:a right-angle horn antenna with a working distance of 5 ***,in further experiments,the optimal parameters were used to irradiate for 20 s and 40 s at a microwave power of 60 kW,*** surface damage extended 38 cm×30 cm and 53 cm×30 cm,respectively,and the damage extended to a depth of about 50 *** drilling speed was increased by 56.2%and 66.5%,respectively,compared to the case when microwaves were not used.

关键词： Microwave parameters High power Field experiment Mechanical mining

Personalized and continuous care intervention affects rehabilitation,living quality,and negative emotions of patients with breast cancer

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World Journal of Psychiatry 2024年第6期14卷 876-883页

作者： Ling-xia Kong Yan-Hong Zhao Zhi-Lin feng ting-ting Liu Department of Breast Surgery The First Affiliated Hospital of Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina Operating Room The First Affiliated Hospital of Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina

BACKGROUND Breast cancer is among the most common malignancies *** progress in treatment methods and levels,the overall survival period has been prolonged,and the demand for quality care has *** To investigate the effect of individualized and continuous care intervention in patients with breast *** Two hundred patients with breast cancer who received systemic therapy at The First Affiliated Hospital of Hebei North University(January 2021 to July 2023)were retrospectively selected as research *** them,134 received routine care intervention(routing group)and 66 received personalized and continuous care(intervention group).Self-rating anxiety scale(SAS),self-rating depression scale(SDS),and Functional Assessment of Cancer Therapy-Breast(FACT-B)scores,including limb shoulder joint activity,complication rate,and care satisfaction,were compared between both groups after *** SAS and SDS scores were lower in the intervention group than in the routing group at one and three months after *** total FACT-B scores and five dimensions in the intervention group were higher than those in the routing group at three months of *** range of motion of shoulder anteflexion,posterior extension,abduction,internal rotation,and external rotation in the intervention group was higher than that in the routing group one month after *** incidence of postoperative complications was 18.18%lower in the intervention group than in the routing group(34.33%;Pting group(78.36%;P<0.05).CONCLUSION Personalized and continuous care can alleviate negative emotions in patients with breast cancer,quicken rehabilitation of limb function,decrease the incidence of complications,and improve living quality and care satisfaction.

关键词： Breast cancer Personalized care Continuous care Negative emotions Living quality Rehabilitation effect

VANET中位置相关的轻量级Sybil攻击检测方法

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通信学报 2017年第4期38卷 110-119页

作者：辛燕冯霞李婷婷江苏大学计算机科学与通信工程学院江苏镇江212013 安徽大学信息保障技术协同创新中心安徽合肥230601

在车联网中,同时使用多个虚假身份的Sybil攻击,在网络中散布虚假消息,都易造成资源的不公平使用和网络混乱。针对这一问题,提出快速识别车辆虚假位置的事件驱动型轻量级算法,当车辆出现在另一车辆的安全区域内,启动快速识别两车辆是否... 详细信息

在车联网中,同时使用多个虚假身份的Sybil攻击,在网络中散布虚假消息,都易造成资源的不公平使用和网络混乱。针对这一问题,提出快速识别车辆虚假位置的事件驱动型轻量级算法,当车辆出现在另一车辆的安全区域内,启动快速识别两车辆是否重叠的几何交叉模型(GCR,geometrical cross-recognition)算法,检测声称虚假位置的错误行为;同时,根据证实车辆收集的邻居范围内的局部车辆,建立位置偏差矩阵(PDM,position deviation matrix),进一步识别交叉车辆中的Sybil节点。性能分析和仿真实验表明,安全区域驱动下的轻量级算法识别速度快,检测率高,在车辆定位误差较低时性能更好;安全区域的引入也均衡了车辆密度过大时造成的通信负载影响,与同类算法相比,通信处理时延较低。

关键词： Sybil攻击几何交叉模型算法位置偏差矩阵轻量级算法

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基于免疫连续蚁群算法的岩土工程反分析研究

岩石力学与工程学报 2005年第23期24卷 4266-4271页

作者：高玮冯夏庭武汉工业学院土木工程系湖北武汉430023 中国科学院武汉岩土力学研究所岩土力学重点实验室湖北武汉430071

基于进化算法等全局优化算法的岩土工程优化反分析是解决实际问题的一种较好的思路,但计算效率是这类算法的最大问题。为了克服这种反分析方法的缺点,提高反分析的计算效率,首次把一种新型仿生算法——连续蚁群算法引入岩土工程领域。... 详细信息

基于进化算法等全局优化算法的岩土工程优化反分析是解决实际问题的一种较好的思路,但计算效率是这类算法的最大问题。为了克服这种反分析方法的缺点,提高反分析的计算效率,首次把一种新型仿生算法——连续蚁群算法引入岩土工程领域。并为了更进一步提高算法的效率,把免疫原理引入连续蚁群算法,提出了免疫连续蚁群新算法。在此基础上,结合有限元数值分析技术,提出了一种新的岩土工程反分析算法——免疫连续蚁群算法反分析。最后,通过一个简单算例验证了该法的有效性及卓越的计算效率。

关键词：岩土力学反分析全局优化算法计算效率连续蚁群算法免疫连续蚁群算法

Asymmetric Partial Hydrosilylation of 2,2-Difluoro-1,3-diketones with Chiral Frustrated Lewis Pairs

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Chinese Journal of Chemistry 2024年第8期42卷 853-857页

作者： ting Liu xiangqing feng Haifeng Du Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing100190 China University of Chinese Academy of Sciences Beijing100049 China

Comprehensive Summary,The asymmetric partial reduction of 1,3-diketones stands as a straightforward pathway to access optically active β-hydroxyketones. In this paper, an asymmetric Piers-type hydrosilylation of 2,2-difluoro-1,3-diketones was successfully realized by using a frustrated Lewis pair of chiral borane and tricyclohexylphosphine as a catalyst, delivering a variety of α,α-difluoro-β-hydroxyketones in high yields with up to 99% ee. Significantly, no over-reduced diol products were observed even with an excess amount of silanes. The product can be conveniently converted to α,α-difluoro-β-hydroxyester or 1,3-anti-diol via an oxidation with m-CPBA or a reduction with DIBAL-H without obvious loss of ee.

关键词： Asymmetric catalysis Hydrosilylation Ketones Frustrated Lewis pairs Chiral boranes