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New method to identify optimal discontinuity set number of rock tunnel excavation face orientation based on Fisher mixed evaluation

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Underground Space 2024年第4期17卷 300-319页

作者： Keshen Zhang wei Wu min Zhang Yongsheng Liu Yong Huang Baolin chen College of Civil Engineering Tongji UniversityShanghai 200092China Key Laboratory of Geotechnical and Underground Engineering of ministry of Education Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China Shudao Investment Group Co.Ltd Chengdu 610095China China Railway Tunnel Group Co.Ltd Guangzhou 511466China China Railway First Survey and Design Institute Group Co.Ltd Xi’an 710043China Zhejiang Institute of Communications Co.Ltd Hangzhou 310012China

Discontinuity is critical for strength,deformability,and permeability of rock *** information is one of the essential discontinuity characteristics and is usually accessed by orientation *** methods of identifying optimal discontinuity set numbers are usually achieved by clustering validity indexes,which mainly relies on the aggregation and dispersion of clusters and leads to the inaccuracy and instability of *** paper proposes a new method of Fisher mixed evaluation(FME)to identify optimal group numbers of rock mass discontinuity *** FME,orientation distribution is regarded as the superposition of Fisher mixed *** grouping results are identified by considering the fitting accuracy of Fisher mixed distributions,the probability monopoly and central location significance of independent Fisher centers.A Halley-Expectation-Maximization(EM)algorithm is derived to achieve an automatic fitting of Fisher mixed *** real rock discontinuity models combined with three orientation clustering algorithms are adopted for discontinuity *** clustering validity indexes are used to automatically identify optimal group numbers for *** results show that FME is more accurate and robust than the other clustering validity indexes in optimal discontinuity group number identification for different rock models and orientation clustering algorithms.

关键词： Rock mass discontinuity Orientation grouping Fisher mixed distribution 3D point cloud Stereo photogrammetry

Recent advances in transition-metal-free trifluoromethylation with Togni’s reagents

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Organic Chemistry Frontiers 2022年第4期9卷 1152-1164页

作者： Jin-Yang chen Jing Huang Kai Sun wei-min He School of Chemistry and Chemical Engineering University of South ChinaHengyangHunan 421001China Green Catalysis Center College of ChemistryZhengzhou UniversityKexue Road No.100Zhengzhou 450001China

Transition-metal-free trifluoromethylations have attracted significant research interest driven by the increasing importance of CF 3-containing *** the various trifluoromethylation reagents,Togni’s reagents exhibit e... 详细信息

关键词： compounds reagents exceptional

Predicting fatigue life of automotive adhesive bonded joints:a data-driven approach using combined experimental and numerical datasets

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Advances in Manufacturing 2024年第3期12卷 522-537页

作者： chen-Di wei Qiu-Ren chen min chen Li Huang Zhong-Jie Yue Si-Geng Li Jian Wang Li chen Chao Tong Qing Liu School of Advanced Technology Xi’an Jiaotong-Liverpool UniversitySuzhou215123People’s Republic of China Key Laboratory for Light-weight Materials Nanjing Tech UniversityNanjing210009People’s Republic of China Material Academy JITRISuzhou215100People’s Republic of China Nanjing University of Science and Technology Nanjing210094People’s Republic of China

The majority of vehicle structural failures originate from joint *** loading is one of the primary factors in joint failures,making the fatigue performance of joints a critical consideration in vehicle structure *** use of traditional fatigue analysis methods is constrained by the absence of adhesive life data and the wide variety of joint ***,there is a pressing need for an accurate fatigue life estimation method for the joints in the automotive *** this work,we proposed a data-driven approach embedding physical knowledge-guided parameters based on experimental data and finite element analysis(FEA)*** machine learning(ML)algorithms are adopted to investigate the fatigue life of three typical adhesive joints,namely lap shear,coach peel and KSII *** the feature engineering and tuned process of the ML models,the preferable model using the Gaussian process regression algorithm is established,fed with eight input parameters,namely thicknesses of the substrates,line forces and bending moments of the adhesive bonded joints obtained from *** proposed method is validated with the test data set and part-level physical tests with complex loading states for an unbiased *** demonstrates that for life prediction of adhesive joints,the data-driven solutions can constitute an improvement over conventional solutions.

关键词： Fatigue life Adhesive bonded joints Finite element analysis(FEA) Machine learning(ML)

振动疗法联合悬吊训练前交叉韧带重建后患者运动及膝关节功能的变化

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中国组织工程研究 2025年第11期29卷 2225-2230页

作者：陈文汉门杰杨伟赵小宇山西医科大学汾阳学院山西省吕梁市032200

背景:物理疗法对前交叉韧带重建术后恢复至关重要。近年来,许多医师都在优化前交叉韧带重建术后的物理康复方案,但仍然缺乏高效的前交叉韧带重建术后康复训练疗法。目的:探讨振动疗法联合悬吊训练对前交叉韧带重建患者术后运动及膝关节... 详细信息

背景:物理疗法对前交叉韧带重建术后恢复至关重要。近年来,许多医师都在优化前交叉韧带重建术后的物理康复方案,但仍然缺乏高效的前交叉韧带重建术后康复训练疗法。目的:探讨振动疗法联合悬吊训练对前交叉韧带重建患者术后运动及膝关节功能的影响。方法:纳入在上海体育大学附属体育医院就诊的80例首次行单侧前交叉韧带重建患者,按照随机数字表法将患者随机分为振动疗法组和振动疗法+悬吊训练组,每组40例。振动疗法组患者在前交叉韧带重建术后第13周开始进行振动疗法训练(每次10 min,1次/d,每周6次),振动疗法+悬吊训练组患者在前交叉韧带重建术后第13周开始进行振动疗法(每次10 min,1次/d,每周6次)联合悬吊训练(每周2次),共训练8周。训练前及训练8后,采用膝关节Lysholm评分评价膝关节功能,采用等速肌力评估训练系统评估屈膝对称性指数,采用平衡测试系统评估双侧多轴平均轨迹误差差值。结果与结论:(1)与训练前比较,两组患者训练8周后的膝关节Lysholm评分、屈膝与伸膝对称性指数均升高(P<0.05),双侧多轴平均轨迹误差差值降低(P<0.05);与振动疗法组比较,振动疗法+悬吊训练组患者膝关节Lysholm评分、屈膝与伸膝对称性指数均升高(P<0.05),双侧多轴平均轨迹误差差值降低(P<0.05);(2)结果表明,与单独进行振动疗法相比,振动疗法联合悬吊训练可显著改善前交叉韧带重建患者的膝关节功能,增加肌肉力量和对称性,提高平衡稳定性。

关键词：前交叉韧带重建振动疗法悬吊训练膝关节功能肌肉力量对称性平衡稳定性

An oversize correction method of dry density for non-cohesive soils filling the embankment of high-speed railway

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Science China(Technological Sciences) 2015年第2期58卷 211-218页

作者： chen Jian LUO Qiang JIANG Liang wei ZHANG Liang ZHAO min Zhi MOE Key Laboratory of High-Speed Railway Engineering Southwest Jiaotong University

Non-cohesive soils have been widely used in construction of high-speed railway for their excellent physical and mechanical properties,and the determination of maximum and minimum dry density of such soils containing oversize particles is an important *** this study,the influence of oversize particles on dry density of non-cohesive soils is investigated by packing *** results show that oversize particles will make"extra"voids around their surfaces,which increase significantly if the size ratio of oversize material to matrix material is not very *** dry density of the total material will be overestimated by Elimination Method due to the omission of the"extra"***,a geometric model is proposed by which the"extra"voids can be taken into account,and a new oversize correction method for non-cohesive soils is *** results confirm the applicability of this method on the condition of oversize fraction being less than 40%by mass.

关键词： high-speed railway oversize correction non-cohesive soils density embankment

NUMERICAL SIMULATION OF THE ENERGY DISSIPATION CHARACTERISTICS IN STILLING BASIN OF MULTI-HORIZONTAL SUBMERGED JETS

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Journal of Hydrodynamics 2010年第5期22卷 732-741页

作者： chen Jian-gang ZHANG Jian-min XU wei-lin WANG Yu-rong State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065 China

3-D numerical simulation was carried out for the water flow in a stilling basin with multi-horizontal submerged jets by using two different turbulence models, namely, the VOF RNG k-ε and Mixture RNG k-ε turbulence models. The calculated water depth, velocity profile and pressure distribution are in good agreement with the data obtained in experiments. It indicates that the numerical simulation can effectively be used to study the water flow movement and the energy dissipation mechanism. The numerical simulation results show that the turbulent kinetic energy distribution obtained by using the Mixture turbulence model covers a region about 18% larger than that calculated by using the VOF turbulence model, and is in better agreement with the actual situation. Furthermore, the Mixture turbulence model is better than the VOF turbulence model in calculating the air entrainment.

关键词： multi-horizontal submerged jets numerical simulation VOF method Mixture method hydraulic characteristics stilling basin

Effect of Sm-doping on the morphology and magnetic properties of radio frequency magnetron sputtered Ni-Mn-Ga films

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International Journal of minerals,Metallurgy and Materials 2012年第6期19卷 555-560页

作者： Feng-hua chen min-gang Zhang Yue-sheng Chai Chang-wei Gong College of Materials Science and Engineering Taiyuan University of Science and Technology Talyuan 030024 China

Ni55.5Mn21Ga23.5 and Ni54Mn22Ga23Sml films were prepared by radio frequency （RF） magnetron sputtering. The effect of Sm do- pant on the morphologic and magnetic properties of Ni55.5Mn21Ga23.5 films was investigated. Sm doping can refine the particle size of the films from 100 to 60 nm, and further grain growth is not occurs even after annealing at 1073 K for 3.6 ks. Compared to Ni55.5Mn21Ga23.5 films, Sm-doped Ni54Mn22Ga23Sml films are easier to be magnetized and have a lower martensitic transformation temperature. In addition, the Curie temperature can also be adjusted, decreasing from 350 to 325 K after Sm doping. Martensitic transformation is not observed in the Sm-free films, which is close to the Curie temperature in the Sm-doped films, giving rise to the overlap of the structural and magnetic transi- tion temperatures.

关键词： magnetic films samarium doping magnetron sputtering martensitic transformation magnetic transition temperature magneticproperties rare earths

Anatomic resection improved the long-term outcome of hepatocellular carcinoma patients with microvascular invasion:A prospective cohort study

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World Journal of Gastrointestinal Oncology 2021年第12期13卷 2190-2202页

作者： Jiang-min Zhou chen-Yang Zhou Xiao-Ping chen Zhi-wei Zhang Hepatic Surgery Center Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030Hubei ProvinceChina Translational Medicine Center Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030Hubei ProvinceChina

BACKGROUND The long-term effect of anatomic resection(AR)is better than that of nonanatomic resection(NAR).At present,there is no study on microvascular invasion(MVI)and liver resection *** To explore whether AR improves long-term survival in patients with hepatocellular carcinoma(HCC)by removing the peritumoral *** A total of 217 patients diagnosed with HCC were enrolled in the *** surgical margin was routinely *** to the stratification of different tumor diameters,patients were divided into the following groups:≤2 cm group,2-5 cm group,and>5 cm *** In the 2-5 cm diameter group,the overall survival(OS)of MVI positive patients was significantly better than that of MVI negative patients(P=0.031).For the MVI positive patients,there was a statistically significant difference between AR and NAR(P=0.027).AR leads to a wider surgical margin than NAR(2.0±2.3 cm vs 0.7±0.5 cm,P5 cm,both AR and NAR fail to obtain wide surgical margin(0.6±1.0 cm vs 0.7±0.4 cm,P=0.491).CONCLUSION For patients with a tumor diameter of 2-5 cm,AR can achieve the removal of peritumoral MVI by obtaining a wide incision margin,reduce postoperative recurrence,and improve prognosis.

关键词： Microvascular invasion Hepatocellular carcinoma Anatomic resection Surgical margin Recurrence Surgery

A Phenol-containing α-Diimine Ligand for Nickel-and Palladium-Catalyzed Ethylene Polymerization

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Chinese Journal of Polymer Science 2019年第10期37卷 974-980,I0003页

作者： chen Tan Wen-min Pang Chang-Le chen Hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and Engineering University of Science and Technology of China

A phenol-containing dibenzhydryl-based α-diimine ligand bearing hydroxy group on para-position of aniline moiety was designed, synthesized, and investigated in Ni-and Pd-catalyzed ethylene polymerization. The Ni complex bearing hydroxy groups resulted in not only high polyethylene molecular weight(Mn up to 1.5 × 10^~6), but also significantly increased melting temperature(Tm up to 123℃) and greatly decreased branching density(33/1000 C) versus the Ni catalyst bearing OMe group on para-position of aniline moiety. This is consistent with the hypothesis that the deprotonation of the phenol moiety generated a phenoxide bearing strong electrondonating O-substituent by methylaluminoxane(MAO) cocatalyst. The Pd complexes bearing hydroxy groups exhibited similar catalytic properties to those of the Pd catalyst bearing OMe groups did.

关键词： α-Diimine Ethylene polymerization Electronic effect Palladium Nickel