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Prediction of fracture initiation in cohesive soils based on data mining modelling and large-scale laboratory verification

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Underground Space 2024年第6期19卷 279-300页

作者： Weiping Luo Dajun Yuan Yannick Choy Hing ng Dalong jin Ping Lu Teng Wang Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Key Laboratory of the Ministry of Education for Urban Underground Engineering Beijing Jiaotong UniversityBeijing 100044China Department of Civil and Environmental Engineering National University of SingaporeSingapore 119077Singapore

Many empirical and analytical methods have been proposed to predict fracturing pressure in cohesive *** of them take into account three to four specific influencing factors and rely on the assumption of a failure *** this study,a novel data-mining approach based on the XGBoost algorithm is investigated for predicting fracture initiation in cohesive *** has the advantage of handling multiple influencing factors simultaneously,without pre-determining a failure mode.A dataset of 416 samples consisting of 14 distinct features was herein collected from past studies,and used for developing a regressor and a classifier model for fracturing pressure prediction and failure mode classification *** results show that the intrinsic characteristics of the soil govern the failure mode while the fracturing pressure is more sensitive to the stress *** XGBoost-based model was also tested against conventional approaches,as well as a similar machine learning algorithm namely random forest ***,several large-scale triaxial fracturing tests and an in-situ case study were carried out to further verify the generalization ability and applicability of the proposed data mining approach,and the results indicate a superior performance of the XGBoost model.

关键词： Fracturing pressure Failure mode Cohesive soil Data-mining Large-scale tests

Shor's algorithm does not factor large integers in the presence of noise

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Science China(Information Sciences) 2024年第7期67卷 305-320页

作者： jin-Yi CAI College of Letters and Science University of Wisconsin

We consider Shor's quantum factoring algorithm in the setting of noisy quantum gates. Under a generic model of random noise for(controlled) rotation gates, we prove that the algorithm does not factor integers of the form pq when the noise exceeds a vanishingly small level in terms of n—the number of bits of the integer to be factored, where p and q are from a well-defined set of primes of positive density. We further prove that with probability 1-o(1) over random prime pairs(p, q), Shor's factoring algorithm does not factor numbers of the form pq, with the same level of random noise present.

关键词： random noise Shor’s algorithm rotation gates quantum computing prime factorization

Semi-analytical Solutions for Wellbores with Graded Skin Zones in Poroelastic Media

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Acta Mechanica Solida Sinica 2024年第3期37卷 385-395页

作者： Zhiqiang Fan Zhihe jin School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an710072China Department of Mechanical Engineering University of MaineOronoME04469USA

In analyzing the complex interaction between the wellbore and the reservoir formation,the hydromechanical properties of the region proximal to the wellbore,referred to as the“wellbore skin zone”,play a pivotal role in determining flow dynamics and the resulting formation *** models of the wellbore skin zone generally assume a constant permeability throughout,resulting in a sharp permeability discontinuity at the skin-reservoir *** paper introduces a model for a wellbore with a continuously graded skin zone of finite thickness within a poroelastic *** solutions are derived using the Laplace transform method,addressing both positive and negative skin *** results are presented to illustrate the effects of graded permeability/skin zone thickness on pore pressures and stresses around a *** results highlight a distinct divergence in stress and pore pressure fields when comparing wellbores with negative skin zones to those with positive skin zones or no skin at all.

关键词： Poroelastic Graded permeability Analytical solution Wellbore Skin zone

From 'glass basins' to 'glass barriers'

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National Science Review 2024年第6期11卷 95-96页

作者： Yuliang jin Institute of Theoretical Physics Chinese Academy of Sciences School of Physical Sciences University of Chinese Academy of Sciences Center for Theoretical Interdisciplinary Sciences Wenzhou InstituteUniversity of Chinese Academy of Sciences

If a supercooled liquid is cooled rapidly to avoid crystallization, a glass is *** this procedure, the viscosity can increase by more than 10 orders of magnitude over a small temperature range near the glass transitio... 详细信息

关键词： LIQUIDS

Advanced Algorithm for Parameters Estimation of Negative Binomial Distribution with High Dimensional Sparse Group Structure

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Journal of Systems Science & Complexity 2024年第5期37卷 2173-2195页

作者： LI Meiqi jin Baisuo School of Management University of Science and Technology of ChinaHefei 230000China

Negative binomial regression is a powerful technique for modeling count data,particularly when dealing with ***,estimating the parameters for large-dimensional sparse models is challenging due to the complexity of optimizing the mean and dispersion parameter of the negative binomial *** address this issue,the authors propose a novel approach that employs two iterations of the majorize-minimize(MM)algorithm,one for estimating the dispersion parameter and the other for estimating the mean *** approaches improve the convergence speed and stability of the *** authors also use group penalty for variable selection,which enhances the accuracy and efficiency of the *** proposed method provides an explicit solution,simplifies the iteration process,and maintains good stability while ensuring algorithm ***,the authors apply the proposed algorithm to the zero-inflated model and demonstrate its promising predictive performance on specific data *** research has important implications for count data modeling and analysis in various fields,such as data mining,machine learning,and bioinformatics.

关键词： Group structure majorize-minimize(MM) negative binomial

Combined Treatment with Bojungikgi-tang(Buzhong Yiqi Decoction)and Riluzole Attenuates Cell Death in TDP-43-Expressing Cells

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Chinese Journal of Integrative Medicine 2024年第7期30卷 616-622页

作者： Eun jin Yang Department of KM Science Research Korea Institute of Oriental MedicineDaejeonYuseong-gu34054Republic of Korea

Objective To examine the effect of combined treatment with Bojungikgi-tang(BJIGT,Buzhong Yiqi Decoction)and riluzole(RZ)in transactive response DNA-binding protein 43(TDP-43)stress granule(SG)cells,a amyotrophic lateral sclerosis(ALS)cell line using transcriptomic and molecular *** TDP-43 SG cells were pretreated with BJIGT(100µg/mL),RZ(50µmol/L),and combined BJIGT(100µg/mL)/RZ(50µmol/L)for 6 h before treatment with lipopolysaccharide(LPS,200µmol/L).Cell viability assay was performed to elucidate cell toxicity in TDP-43 SC cells using a cell-counting kit-8(CCK8)assay *** expression levels of cell death-related proteins,including Bax,caspase 1,cleaved caspase 3 and DJ1 in TDP-43 SG cells were examined by Western blot *** autophagy-related proteins,including pmTOR/mTOR,LC3b,P62,ATG7 and Bcl-2-associated athanogene 3(Bag3)were investigated using immunofluorescence and immunoblotting *** Cell viability assay and Western blot analysis showed that combined treatment with BJIGT and RZ suppressed LPS-induced cell death and expression of cell death-related proteins,including Bax,caspase 1,and DJ1(P1).Immunofluorescence and immunoblotting assays showed that combined treatment with BJIGT and RZ reduced LPS-induced formation of TDP-43 aggregates and regulated autophagy-related protein levels,including p62,light chain 3b,Bag3,and ATG7,in TDP-43-expressing cells(P1).Conclusion The combined treatment of BJIGT and RZ might reduce inflammation and regulate autophagy dysfunction in TDP-43-induced ALS.

关键词： Bojungikgi-tang Buzhong Yiqi Decoction transactive response DNA-binding protein 43 autophagy oxidative stress amyotrophic lateral sclerosis

Modeling and Validation of Diamagnetic Rotor Levitated by Permanent Magnetics

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 224-235页

作者： Yuanping Xu Yue Zhang jin Zhou Chaowu jin College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

As an innovative,low-power consuming,and low-stiffness suspension approach,the diamagnetic levitation technique has attracted considerable interest because of its potential applicability in miniaturized mechanical *** foundation of a diamagnetic levitation system is mathematical modeling,which is essential for operating performance optimization and stability ***,few studies on systematic mathematical modeling have been *** this study,a systematic mathematical model for a disc-shaped diamagnetically levitated rotor on a permanent magnet array is *** on the proposed model,the magnetic field distribution characteristics,diamagnetic levitation force characteristics(i.e.,levitation height and stiffness),and optimized theoretical conditions for realizing stable levitation are *** are conducted to verify the feasibility of the proposed mathematical *** predictions and experimental results indicate that increasing the levitation height enlarges the stable ***,with a further increase in the rotor radius,the stable regions of the rotor gradually diminish and even ***,when the levitation height is fixed,a moderate rotor radius permits stable *** study proposes a mathematical modeling method for a diamagnetic levitation system that has potential applications in miniaturized mechanical systems.

关键词： Diamagnetic levitation Magnetic levitation Rotor Modeling Validation Stability

Mobility of rhenium and selenium during chemical weathering and their implication for petrogenic organic carbon oxidation

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Science China Earth Sciences 2024年第3期67卷 740-750页

作者： Yuhong ZHAng jin WAng Yuanxin QU Chao ZHU Zhangdong jin State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China University of Chinese Academy of Sciences Beijing 100049China Xi'an Institute for Innovative Earth Environment Research Xi'an 710061China Institute of Global Environmental Change Xi'an Jiaotong UniversityXi'an 710049China

The oxidative weathering of petrogenic organic carbon(OC_(petro)) is an important source of carbon dioxide(CO_(2)) into the atmosphere on geological timescales and significantly influences the carbon cycle and global climate change. However, at present, a robust proxy to assess OC_(petro)oxidation is lacking. Riverine rhenium(Re) has emerged as a potential proxy to trace OC_(petro)oxidation, but little is known about Re sources and its relationship with OC_(petro)oxidation. To better understand the robustness of this proxy, we analyzed a shale weathering profile from the early Cambrian Shuijingtuo Formation in Chengkou County, Chongqing City, to address the mobility of Re and selenium(Se) and their relationship with the oxidation of OC_(petro)by analyses of the elemental variation and sequential extraction. The results showed that the chemical index of alteration(CIA)increases from the fresh bedrock to the weathered sections, indicating enhanced weathering intensity. Based on the sequential extraction and mass transfer coefficients(τ), Re and Se mainly exist in the organic phase of shale and are paired lost with OC_(petro) during weathering, with no obvious correlation with sulfide minerals. Furthermore, the different proportions of Re and Se loss with OC_(petro) loss can be attributed to their different geochemical behaviors during weathering. Our study supports Re as a robust proxy to trace OC_(petro) oxidation, whereas Se is the potential one. In the future, combined studies on various sedimentary rock profiles with catchment basins are needed to determine the sources of riverine Re and Se and their relationships with OC_(petro) oxidation.

关键词： Rhenium and selenium Shale Mobility OC_(petro) Chemical weathering

Recent Progresses of the DAMPE Mission

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空间科学学报 2024年第4期44卷 633-642页

作者： CHAng jin Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210033 School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026

The DArk Matter Particle Explorer(DAMPE)is a space high-energy particle andγ-ray detector whose major scientific goals are the indirect detection of dark matter particles,the origin of cosmic rays and highenergyγ-ray *** its successful launch in December 2015,the DAMPE has been operated smoothly in orbit for more than 8 *** direct measurements of the boron-to-carbon and boron-to-oxygen flux ratios,and the proton+Helium spectrum up to 316 TeV have been obtained,revealing new spectral features with very high *** search results ofγ-ray spectral line and fractionally charged particles indicate a good potential of DAMPE for indirect dark matter detection and new physical discovery in *** DAMPE measurements are expected to significantly advance our understanding of the fundamental problems in astroparticle physics.

关键词： DAMPE Dark matter Indirect detection Cosmic rays