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Sub-Homogeneous Peridynamic Model for Fracture and Failure Analysis of Roadway Surrounding Rock

Computer Modeling in Engineering & Sciences 2024年第6期139卷 3167-3187页

作者： shijun zhao Qing Zhang Yusong Miao Weizhao Zhang Xinbo zhao Wei Xu School of Science Qingdao University of TechnologyQingdao266520China College of Mechanics and Materials Hohai UniversityNanjing211100China Xibei Mining Co. Ltd.Shandong Energy GroupXi’an710018China

The surrounding rock of roadways exhibits intricate characteristics of discontinuity and *** address these complexities,this study employs non-local Peridynamics(PD)theory and reconstructs the kernel function to represent accurately the spatial decline of long-range ***,modifications to the traditional bondbased PD model are *** considering the micro-structure of coal-rock materials within a uniform discrete model,heterogeneity characterized by bond random pre-breaking is *** approach facilitates the proposal of a novel model capable of handling the random distribution characteristics of material heterogeneity,rendering the PD model suitable for analyzing the deformation and failure of heterogeneous layered coal-rock mass *** established numerical model and simulation method,termed the sub-homogeneous PD model,not only incorporates the support effect but also captures accurately the random heterogeneous micro-structure of roadway surrounding *** simulation results obtained using this model show good agreement with field measurements from the Fucun coal mine,effectively validating the model’s capability in accurately reproducing the deformation and failure mode of surrounding rock under bolt-supported(anchor cable).The proposed subhomogeneous PD model presents a valuable and effective simulation tool for studying the deformation and failure of roadway surrounding rock in coal mines,offering new insights and potential advancements.

关键词： Roadway surrounding rock peridynamics heterogeneous material fracture analysis numerical simulation

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A STAMP-Game model for accident analysis in oil and gas industry

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Petroleum Science 2024年第3期21卷 2154-2167页

作者： Huixing Meng Xu An Daiwei Li shijun zhao Enrico Zio Xuan Liu Jinduo Xing State Key Laboratory of Explosion Science and Safety Protection Beijing Institute of TechnologyBeijing100081China School of Emergency Management and Safety Engineering China University of Mining and Technology(Beijing)Beijing100083China Energy Department Politecnico di MilanoVia La Masa 34Milan20156Italy Mines Paris PSL Centre de Recherche sur les Risques et les CrisesSophie Antipolis06904France School of Mechanical-Electronic and Vehicle Engineering Beijing University of Civil Engineering and ArchitectureBeijing100044China

Accidents in engineered systems are usually generated by complex socio-technical *** is beneficial to investigate the increasing complexity and coupling of these factors from the perspective of system *** on system and control theories,System-Theoretic Accident Model and Processes(STAMP)is a widely recognized approach for accident *** this paper,we propose a STAMP-Game model to analyze accidents in oil and gas storage and transportation *** in accident analysis by STAMP can be regarded as players of a *** theory can,thus,be adopted in accident analysis to depict the competition and cooperation between ***,we established a game model to study the strategies of both supervisory and supervised *** obtained results demonstrate that the proposed game model allows for identifying the effectiveness deficiency of the supervisory entity,and the safety and protection altitudes of the supervised *** STAMP-Game model can generate quantitative parameters for supporting the behavior and strategy selections of the supervisory and supervised *** quantitative data obtained can be used to guide the safety improvement,to reduce the costs of safety regulation violation and accident risk.

关键词： Accident analysis STAMP System engineering Gametheory Oil and gas storage and transportation systems

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早期血管介入栓塞治疗颅内动脉瘤对其疗效及神经功能的影响

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系统医学 2024年第3期9卷 11-15页

作者：赵士军唐山市丰润区人民医院血管介入科河北唐山064000

目的探讨颅内动脉瘤的患者采取早期血管介入栓塞治疗的效果,并分析对神经功能的影响。方法选取2021年3月—2023年3月在唐山市丰润区人民医院接受治疗的100例颅内动脉瘤患者为研究对象,按照双盲法对患者进行分组,即参照组与研究组,每组5... 详细信息

目的探讨颅内动脉瘤的患者采取早期血管介入栓塞治疗的效果,并分析对神经功能的影响。方法选取2021年3月—2023年3月在唐山市丰润区人民医院接受治疗的100例颅内动脉瘤患者为研究对象,按照双盲法对患者进行分组,即参照组与研究组,每组50例。参照组给予晚期(发病72 h后)血管介入栓塞治疗,研究组给予早期(发病72 h内)血管介入栓塞治疗,比较两组临床疗效、神经功能缺损程度、日常生活能力、血清炎性因子水平、并发症发生情况。结果研究组临床总有效率(96.00%)明显高于参照组,差异有统计学意义(χ^(2)=5.005,P=0.025)。治疗后,研究组日常生活能力评分(90.35±4.73)分高于对照组,神经功能缺损程度评分(6.42±1.58)分低于对照组,差异有统计学意义(t=3.754、11.868,P均<0.05)。治疗后,研究组白细胞介素-6水平(180.38±18.84)pg/mL、肿瘤坏死因子-α水平为(330.85±20.81)pg/mL显著低于对照组,白细胞介素-10水平为(23.19±3.80)pg/mL高于对照组,差异有统计学意义(t=5.257、4.804、4.550,P均<0.05)。研究组并发症发生率(4.00%)明显低于参照组,差异有统计学意义(χ^(2)=4.000,P=0.046)。结论颅内动脉瘤患者应用早期血管介入栓塞治疗的临床疗效更确切,不仅能够进一步改善神经功能与日常生活能力,还可以有效调节炎性因子水平,降低并发症发生率。

关键词：颅内动脉瘤早期血管介入栓塞临床疗效神经功能日常生活能力并发症

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光声层析重建飞秒光丝二维横向图像仿真研究

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光学学报 2024年第12期44卷 101-111页

作者：曾庆伟刘磊胡帅李书磊赵世军国防科技大学气象海洋学院湖南长沙410073 中国气象局高影响天气重点开放实验室湖南长沙410073

准确获取飞秒激光成丝横截面图像及其沉积能量空间分布信息,对于成丝动力机制研究和促进诸多基于光丝的实际大气应用发展具有重要意义。本文基于热传导方程和波动方程构成的光声信号前向仿真模型,理论模拟了利用环阵式光声层析系统接收... 详细信息

准确获取飞秒激光成丝横截面图像及其沉积能量空间分布信息,对于成丝动力机制研究和促进诸多基于光丝的实际大气应用发展具有重要意义。本文基于热传导方程和波动方程构成的光声信号前向仿真模型,理论模拟了利用环阵式光声层析系统接收飞秒激光在空气介质中成丝诱导产生超声脉冲信号的过程;然后,利用延迟叠加算法对飞秒激光大气传输成丝沉积能量横向分布图像进行了反向重建,并分析了测量系统中关键器件超声换能器的中心频率、带宽、表面尺寸和探测表面灵敏度等性能参数对光丝沉积能量分布图像重建结果的影响。结果表明,单丝诱导产生的声压脉冲信号频谱为单峰结构,而多丝声压脉冲信号频谱为多峰结构;相比于单丝图像重建,多丝图像重建受“孔径效应”影响更显著;换能器的性能参数对光丝图像的重建效果有显著的影响,换能器的带宽越大、表面直径越小,以及表面灵敏度系数越大,越有利于光丝沉积能量分布图像重建效果的提升。该研究结果可为真实大气条件下飞秒激光传输成丝沉积能量空间分布的实验测量提供一定的理论支撑。

关键词：飞秒激光激光成丝能量沉积光声信号超声换能器反投影

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Defect properties in a VTaCrW equiatomic high entropy alloy(HEA)with the body centered cubic(bcc)structure

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Journal of Materials Science & Technology 2020年第9期44卷 133-139页

作者： shijun zhao Department of Mechanical Engineering City University of Hong KongHong KongChina

We report first-principles results of the point defect properties in a V-Ta-Cr-W high-entropy alloy(HEA)with the body-centered cubic(bcc)*** from the widely-investigated face-centered cubic(fcc)HEAs,the local lattice distortion is more pronounced in bcc ones,which has a strong influence on the defect properties and defect evolution under *** to the large size of Ta,the exchange between vacancies and Ta exhibits lower energy *** the other hand,interstitial dumbbells containing V and Cr possess lower formation *** defect energetics predicts an enrichment of V and Cr and a depletion of Ta andWin the vicinity of defect ***,we find that interstitial dumbbells favor the[110]orientation in the HEA,instead of[111]direction in most nonmagnetic bcc metals,which helps to slow down interstitial diffusion ***,the distribution of migration energies for vacancies and interstitials exhibit much larger overlap regions in the bcc HEA compared to fcc HEAs,leading to the good irradiation resistance by enhancing defect *** results suggest that HEAs with the bcc structure may bear excellent irradiation tolerance due to the particular defect properties.

关键词： High-entropy alloys Defect properties Radiation tolerance First-principles calculations Lattice distortion

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基于近场动力学的窄煤柱宽度优化研究

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固体力学学报 2024年第3期45卷 363-378页

作者：赵世军章青张惟昭缪玉松赵新波青岛理工大学理学院青岛266520 河海大学力学与材料学院南京211100 山东能源集团西北矿业有限公司西安710018

煤岩体具有极为复杂的非连续变形、非均质性特征,以有限元法为代表的传统数值方法难以准确描述其损伤累积、渐进破坏全过程.基于非局部近场动力学方法(Peridynamics,PD),通过重构本构力函数核函数,推导了相应的微模量函数与临界伸长率.... 详细信息

煤岩体具有极为复杂的非连续变形、非均质性特征,以有限元法为代表的传统数值方法难以准确描述其损伤累积、渐进破坏全过程.基于非局部近场动力学方法(Peridynamics,PD),通过重构本构力函数核函数,推导了相应的微模量函数与临界伸长率.在均匀离散模型中引入用随机预断“键”表征的非均质性,使近场动力学方法能够适用于天然非均质材料与结构的非连续变形破坏分析.以付村煤矿为例,建立了近场动力学数值计算模型,分析了不同煤柱宽度条件下巷道围岩变形、破坏规律以及煤柱破损特征.研究发现:当煤柱宽度为5 m时,巷道煤壁处于挤压变形区边缘,由于支承压力剧烈变化,巷帮变形破损严重;煤柱宽度增大至6 m和7 m时,巷道煤壁逐渐远离挤压变形区,煤柱受到采空区基本顶回转运动的影响相对减弱,巷帮变形和破损量较小;当煤柱宽度继续增大,巷道围岩将进入到应力增高区域,由于外应力场支承压力较大,巷帮变形及破损量会随之增大.综合考虑巷道围岩变形破坏、煤柱破损特征,最终确定煤柱留设宽度为7 m.本文工作表明,提出的煤岩体破损分析的近场动力学模型能够有效描述煤岩体的损伤累积和渐进破坏过程,为沿空掘巷护巷煤柱尺寸优化提供了新的计算工具.

关键词：近场动力学沿空掘巷煤柱尺寸数值模拟宽度优化

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Influence of temperature and alloying elements on the threshold displacement energies in concentrated Ni-Fe-Cr alloys

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Chinese Physics B 2021年第5期30卷 106-113页

作者： shijun zhao Department of Mechanical Engineering City University of Hong KongHong KongChina

Concentrated solid-solution alloys(CSAs)have demonstrated promising irradiation resistance depending on their *** irradiation,various defects can be *** of the most important parameters characterizing the defect production and the resulting defect number is the threshold displacement energies(Ed).In this work,we report the results of Ed values in a series of Ni-Fe-Cr concentrated solid solution alloys through molecular dynamics(MD)*** on several different empirical potentials,we show that the differences in the Ed values and its angular dependence are mainly due to the stiffness of the potential in the intermediate *** influences of different alloying elements and temperatures on Ed values in different CSAs are further evaluated by calculating the defect production *** results suggest a limited influence of alloying elements and temperature on Ed values in concentrated ***,we discuss the relationship between the primary damage and Ed values in different ***,this work presents a thorough study on the Ed values in concentrated alloys,including the influence of empirical potentials,their angular dependence,temperature dependence,and effects on primary defect production.

关键词： irradiation effects molecular dynamics threshold displacement energies concentrated high-entropy alloys

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Updated overall survival and circulating tumor DNA analysis of ensartinib for crizotinib-refractory ALK-positive NSCLC from a phase II study

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Cancer Communications 2024年第4期44卷 455-468页

作者： Jing Zheng Tao Wang Yunpeng Yang Jie Huang Jifeng Feng Wu Zhuang Jianhua Chen Jun zhao Wei Zhong Yanqiu zhao Yiping Zhang Yong Song Yi Hu Zhuang Yu Youling Gong Yuan Chen Feng Ye Shucai Zhang Lejie Cao Yun Fan Gang Wu Yubiao Guo Chengzhi Zhou Kewei Ma Jian Fang Weineng Feng Yunpeng Liu Zhendong Zheng Gaofeng Li Huijie Wang Shundong Cang Ning Wu Wei Song Xiaoqing Liu shijun zhao Lieming Ding Giovanni Selvaggi Yang Wang Shanshan Xiao Qian Wang Zhilin Shen Jianya Zhou Jianying Zhou Li Zhang Department of Respiratory Disease Thoracic Disease CenterThe First Affiliated HospitalCollege of MedicineZhejiang UniversityZhejiang Provincial Clinical Research Center for Respiratory DiseaseHangzhouZhejiangP.R.China Hangzhou Repugene Technology Co. LtdHangzhouZhejiangP.R.China Department of Medical Oncology Sun Yat-sen University Cancer Cen-terState Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineGuangzhouGuangdongP.R.China Department of Medical Oncology Jiangsu Cancer HospitalJiangsu Institute of Cancer ResearchThe Affiliated Cancer Hospital of Nanjing Medical UniversityNanjingJiangsuP.R.China Department of Thoracic Oncology Fujian Provincial Cancer HospitalFujian Medical University Cancer HospitalFuzhouFujianP.R.China Department of Medical Oncology-Chest Hunan Cancer HospitalChangshaHunanP.R.China Department of Thoracic Oncology Beijing Cancer HospitalBeijingP.R.China Department of Pulmonary Medicine Peking Union Medical College HospitalChinese Academy of Medical SciencesPeking Union Medical CollegeBeijingP.R.China Respiratory Department of Internal Medicine Henan Provincial Can-cer HospitalAffiliated Cancer Hospital of Zhengzhou UniversityZhengzhouHenanP.R.China Thoracic Medical Oncology Zhejiang Cancer HospitalHangzhouZhejiangP.R.China Division of Respiratory Medicine Jinling HospitalNanjing University School of MedicineNanjingJiangsuP.R.China Department of Oncology Chinese People’s Liberation Army(PLA)General HospitalBeijingP.R.China Department of Oncology The Affiliated Hospital of Qingdao UniversityQingdaoShandongP.R.China Department of Thoracic Oncology Cancer CenterWest China HospitalSichuan UniversityChengduSichuanP.R.China Department of Oncology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubeiP.R.China Department of Medical Oncology Cancer HospitalThe First Affiliated Hospital of Xiamen UniversitySchool of MedicineXiamen UniversityTeaching Hospital of

Background:The initial phase II stuty(NCT03215693)demonstrated that ensartinib has shown clinical activity in patients with advanced crizotinib-refractory,anaplastic lymphoma kinase(ALK)-positive non-small cell lung cancer(NSCLC).Herein,we reported the updated data on overall survival(OS)and molecular profiling from the initial phase Ⅱ ***:In this study,180 patients received 225 mg of ensartinib orally once daily until disease progression,death or *** was estimated by Kaplan‒Meier methods with two-sided 95%confidence intervals(CIs).Next-generation sequencing was employed to explore prognostic biomarkers based on plasma samples collected at baseline and after initiating *** tumor DNA(ctDNA)was detected to dynamically monitor the genomic alterna-tions during treatment and indicate the existence of molecular residual disease,facilitating improvement of clinical ***:At the data cut-off date(August 31,2022),with a median follow-up time of 53.2 months,97 of 180(53.9%)patients had *** median OS was 42.8 months(95%CI:29.3-53.2 months).A total of 333 plasma samples from 168 patients were included for ctDNA *** inferior OS correlated sig-nificantly with baseline ALK or tumor protein 53(TP53)*** addition,patients with concurrent TP53 mutations had shorter OS than those without con-current TP53 *** ctDNA levels evaluated by variant allele frequency(VAF)and haploid genome equivalents per milliliter of plasma(hGE/mL)at baseline were associated with poor ***,patients with ctDNA clear-ance at 6 weeks and slow ascent growth had dramatically longer OS than those with ctDNA residual and fast ascent growth,***,patients who had a lower tumor burden,as evaluated by the diameter of target lesions,had a longer *** Cox regression analysis further uncovered the independent prognostic values of bone metastases,higher hGE,and elevated ALK mutation abundance at 6 we

关键词： anaplastic lymphoma kinase ctDNA ensartinib non-small cell lung cancer overall survival

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Visibility Characteristics over the South China Sea during 1980-2018 Based on Gridded Data Generated by Artificial Neural Network

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Journal of Meteorological Research 2021年第4期35卷 690-700页

作者： Lifeng LI Yulong SHAN shijun zhao School of Meteorology and Oceanography National University of Defense TechnologyChangsha 430073

This paper generated gridded visibility(Vis)data from 1980 to 2018 over the South China Sea(SCS)based on artificial neural network(ANN),and the accuracy of the generated data was ***,temporal and spatial characteristics of Vis in the area were analyzed based on the generated Vis *** results showed that Vis in the southern SCS was generally better than that in the northern *** the past 39 years,Vis in both spring and winter has improved,especially in winter at a significant increased speed of 0.37 km decade^(-1).However,Vis in both summer and autumn has decreased,especially in summer with an obvious reduction of 0.84 km decade^(-1).Overall,Vis is best in summer and worst in winter,averaging 31.89 km in summer and 20.96 km in winter,which may be related to the difference of climatic conditions and wind speed in different *** the same time,probability of low Vis in spring is significantly higher than that in other seasons,especially in the northwest of Hainan Island and the northwest of Malaysia.

关键词： visibility(Vis) spatiotemporal characteristics South China Sea

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Prediction of visibility in the Arctic based on dynamic Bayesian network analysis

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Acta Oceanologica Sinica 2022年第4期41卷 57-67页

作者： shijun zhao Yulong Shan Ismail Gultepe College of Meteorology and Oceanography National University of Defense TechnologyNanjing 211101China Cloud Physics and Severe Weather Research Environment and Climate Change CanadaToronto M4Y1M7Canada

With the accelerated warming of the world,the safety and use of Arctic passages is receiving more *** visibility in the Arctic has been a hot topic in recent years because of navigation risks and opening of ice-free northern *** weather prediction and statistical prediction are two methods for predicting *** microphysical parameterization schemes for visibility are so sophisticated,visibility prediction using numerical weather prediction models includes large *** the development of artificial intelligence,statistical prediction methods have received increasing *** this study,we constructed a statistical model with a physical basis,to predict visibility in the Arctic based on a dynamic Bayesian network,and tested visibility prediction over a 1°×1°grid area averaged *** results show that the mean relative error of the predicted visibility from the dynamic Bayesian network is approximately 14.6%compared with the inferred visibility from the artificial neural ***,dynamic Bayesian network can predict visibility for only 3 ***,with an increase in predicted area and period,the uncertainty of the predicted visibility becomes *** the same time,the accuracy of the predicted visibility is positively correlated with the time period of the input evidence *** is concluded that using a dynamic Bayesian network to predict visibility can be useful over Arctic regions for projected climatic changes.

关键词： Arctic visibility prediction artificial neural network dynamic Bayesian network

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