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Failure mechanisms and destruction characteristics of cemented coal gangue backfill under compression effect of non-uniform load

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Journal of Central South University 2024年第8期31卷 2676-2693页

作者： Feng, Guo-rui Guo, Wei Qi, Ting-ye Li, Zhu Cui, Jia-qing Wang, Hao-chen Cui, Ye-kai ma, jing-kai College of Mining Engineering Taiyuan University of Technology Taiyuan China Shanxi Province Research Center of Green Mining Engineering Technology Taiyuan China Shanxi Province Coal-based Resources Green and High-efficiency Development Engineering Center Taiyuan China Shanxi Key Laboratory of Mine Rock Strata Control and Disaster Prevention Taiyuan China

Backfill mining is one of the most important technical means for controlling strata movement and reducing surface subsidence and environmental damage during exploitation of underground coal resources. Ensuring the stability of the backfill bodies is the primary prerequisite for maintaining the safety of the backfilling working face, and the loading characteristics of backfill are closely related to the deformation and subsidence of the roof. Elastic thin plate model was used to explore the non-uniform subsidence law of the roof, and then the non-uniform distribution characteristics of backfill bodies’ load were revealed. Through a self-developed non-uniform loading device combined with acoustic emission (AE) and digital image correlation (DIC) monitoring technology, the synergistic dynamic evolution law of the bearing capacity, apparent crack, and internal fracture of cemented coal gangue backfills (CCGBs) under loads with different degrees of non-uniformity was deeply explored. The results showed that: 1) The uniaxial compressive strength (UCS) of CCGB increased and then decreased with an increase in the degree of non-uniformity of load (DNL). About 40% of DNL was the inflection point of DNL-UCS curve and when DNL exceeded 40%, the strength decreased in a cliff-like manner; 2) A positive correlation was observed between the AE ringing count and UCS during the loading process of the specimen, which was manifested by a higher AE ringing count of the high-strength specimen. 3) Shear cracks gradually increased and failure mode of specimens gradually changed from “X” type dominated by tension cracks to inverted “Y” type dominated by shear cracks with an increase in DNL, and the crack opening displacement at the peak stress decreased and then increased. The crack opening displacement at 40% of the DNL was the smallest. This was consistent with the judgment of crack size based on the AE b-value, i.e., it showed the typical characteristics of “small b-value-large crack and

关键词： cemented coal gangue backfill crack opening displacement degree of non-uniformity of load failure mode non-uniform load

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Autonomous navigation method of satellite constellation based on adaptive forgetting factors

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Chinese Journal of Aeronautics 2024年第7期37卷 317-332页

作者： Dong WANG jing YANG kai XIONG School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Science and Technology on Space Intelligent Control Laboratory Beijing Institute of Control EngineeringBeijing 100094China

To address the problem that model uncertainty and unknown time-varying system noise hinder the filtering accuracy of the autonomous navigation system of satellite constellation,an autonomous navigation method of satellite constellation based on the Unscented Kalman Filter with Adaptive Forgetting Factors(UKF-AFF)is *** process noise covariance matrix is estimated online with the strategy that combines covariance matching and adaptive adjustment of forgetting *** adaptive adjustment coefficient based on squared mahalanobis distance of state residual is employed to achieve online regulation of forgetting factors,equipping this method with more *** intersatellite direction vector obtained from photographic observations is introduced to determine the constellation satellite orbit together with the distance measurement to avoid rank deficiency *** that the number of available measurements varies online with intersatellite visibility in practical applications such as time-varying constellation configurations,the smooth covariance matrix of state correction determined by innovation and gain is adopted and constructed *** analysis of the proposed method is also *** effectiveness of the proposed method is verified by the Monte Carlo simulation and comparison *** estimation accuracy of constellation position and velocity of UKF-AFF is improved by 30%and 44%respectively compared to those of the extended Kalman filter,and the method proposed is also better than other several adaptive filtering methods in the presence of significant model uncertainty.

关键词： Constellation autonomous navigation Unscented Kalman filter Adaptive forgetting factor Model uncertainty Stability analysis

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Inhibiting HMGCR represses stemness and metastasis of hepatocellular carcinoma via Hedgehog signaling

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Genes & Diseases 2024年第5期11卷 470-483页

作者： Zhirong Zhang Jiayao Yang Rui Liu jing ma kai Wang Xiaojun Wang Ni Tang Key Laboratory of Molecular Biology for Infectious Diseases(Ministry of Education) Institute for Viral HepatitisDepartment of Infectious DiseasesThe Second Affiliated HospitalChongqing Medical UniversityChongqing 400016China Institute of Hepatobiliary Surgery Southwest HospitalThird Military Medical University(Army Medical University)Chongqing 400038China

Cancer stem cells(CSCs)play a crucial role in tumor initiation,recurrence,metastasis,and drug ***,the current understanding of CSCs in hepatocellular carcinoma(HCC)remains *** a comprehensive analysis of the database,it has been observed that 3-hydroxy-3-methylglutaryl-coenzyme A reductase(HMGCR),a critical enzyme involved in cholesterol synthesis,is up-regulated in HCC tissues and liver ***,high expression of HMGCR is associated with a poor prognosis in patients with ***,HMGCR promotes the stemness and metastasis of HCC both in vitro and in *** screening various signaling pathway inhibitors,we have determined that HMGCR regulates stemness and metastasis by activating the Hedgehog signaling in ***,HMGCR positively correlates with the expression of the Smoothened receptor and facilitates the nuclear translocation of the transcriptional activator GLI family zinc finger *** of the Hedgehog pathway can reverse the stimulatory effects of HMGCR on stemness and metastasis in ***,simvastatin,an FDA-approved cholesterol-lowering drug,has been shown to inhibit stemness and metastasis of HCC by targeting *** together,our findings suggest that HMGCR promotes the regeneration and metastasis of HCC through the activation of Hedgehog signaling,and simvastatin holds the potential for clinical suppression of HCC metastasis.

关键词： Cancer stem cells Hedgehog Hepatocellular carcinoma Metastasis Statin

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Testing Bell inequality through h→ττ at CEPC

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Chinese Physics C 2024年第10期48卷 59-71页

作者： kai ma Tong Li Faculty of Science Xi'an University of Architecture and TechnologyXi'an 710055China School of Physics Nankai UniversityTianjin 300071China

The decay of Higgs boson into two spin-1/2 particles provides an ideal system to reveal quantum entanglement and *** e^(+)e^(-) colliders can improve the measurement accuracy of the spin correlation of tau lepton pairs from Higgs boson *** show the testability of Bell inequality through h→ττ at Circular Electron Positron Collider(CEPC).Two realistic methods of testing Bell inequality are investigated,i.e.,Törnqvist's method and Clauser-Home-Shimony-Holt(CHSH)*** the simulation,we consider the detector effects of CEPC including uncertainties for tracks and jets from Z boson in the production of e^(+)e^(-)→*** reconstruction approaches are described to measure quantum entanglement between τ^(+) and τ^(-).Finally,we show the sensitivity of CEPC to Bell inequality violation for the two methods.

关键词： Bell inequality Higgs boson CEPC

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A Robust Framework for Multimodal Sentiment Analysis with Noisy Labels Generated from Distributed Data Annotation

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2965-2984页

作者： kai Jiang Bin Cao jing Fan School of Computer Science and Technology Zhejiang University of TechnologyHangzhou310023China

Multimodal sentiment analysis utilizes multimodal data such as text,facial expressions and voice to detect people’s *** the advent of distributed data collection and annotation,we can easily obtain and share such multimodal ***,due to professional discrepancies among annotators and lax quality control,noisy labels might be *** research suggests that deep neural networks(DNNs)will overfit noisy labels,leading to the poor performance of the *** address this challenging problem,we present a Multimodal Robust Meta Learning framework(MRML)for multimodal sentiment analysis to resist noisy labels and correlate distinct modalities ***,we propose a two-layer fusion net to deeply fuse different modalities and improve the quality of the multimodal data features for label correction and network ***,a multiple meta-learner(label corrector)strategy is proposed to enhance the label correction approach and prevent models from overfitting to noisy *** conducted experiments on three popular multimodal datasets to verify the superiority of ourmethod by comparing it with four baselines.

关键词： Distributed data collection multimodal sentiment analysis meta learning learn with noisy labels

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Coexistence of liver abscess, hepatic cystic echinococcosis and hepatocellular carcinoma: A case report

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World Journal of Clinical Cases 2024年第14期12卷 2404-2411页

作者： Ya-Wen Hu Yi-Lin Zhao jing-Xin Yan Cun-kai ma Department of Interventional Therapy The Affiliated Hospital of Qinghai UniversityXining 810000Qinghai ProvinceChina West China Hospital Sichuan UniversityChengdu 610000Sichuan ProvinceChina

BACKGROUND Human cystic echinococcosis(CE)is a life-threatening zoonosis caused by the Echinococcus granulosus(sensu lato).Hepatocellular carcinoma(HCC)is a leading cause of cancer-related mortality in the *** coexistence of CE and HCC is exceedingly rare,and only several well-documented cases have been *** addition to this coexistence,there is no report of the coexistence of CE,HCC,and liver abscess to ***,we aimed to report a case of coexistence of liver abscess,hepatic CE,and *** SUMmaRY A 65-year-old herdsman presented to the department of interventional therapy with jaundice,right upper abdominal distension and pain for 10 *** test showed that he had positive results for HBsAg,HBeAb,HBcAb,and echino-coccosis IgG *** test also showed an increased level of alpha fetopro-tein of 3400 ng/*** abdominal computed tomography(CT)scan revealed an uneven enhanced lesion of the liver at the arterial phase with enhancement and was located S4/8 segment of the *** addition,CT scan also revealed a mass in the S6 segment of the liver with a thick calcified wall and according to current guideline and medical images,the diagnoses of hepatic CE(CE4 subtype)and HCC were ***,transarterial chemoembolization was performed for *** the follow-up,liver abscess occurred in addition to CE and HCC;thus,percutaneous liver puncture drainage was *** the next follow-up,CE and HCC were *** liver abscess was completely resolved,and the patient was discharged with no evidence of *** This is the first reported case on the coexistence of liver abscess,hepatic CE,and *** treatment and multidisciplinary discussions should be performed in this ***,treatment and diagnosis should be based on the characteristics of liver abscess,hepatic CE,and HCC,and in future clinical work,it is necessary to be aware of the possibility of this complex composition of liver diseases.

关键词： Cystic echinococcosis Hepatocellular carcinoma Liver abscess Multidisciplinary discussions Case report

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Effects of hot deformation and in-situ ZrB2 particle on microstructure and tensile performance of AA7085 composite sheets

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Journal of Iron and Steel Research International 2024年第7期31卷 1778-1791页

作者： Jiang-jing Wu Xi-zhou kai Chuang Guan Yu-tao Zhao School of material Science and Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

To provide a new idea to reduce anisotropy for sheets in the thickness direction by microstructure modification and,mean-while,maintain or even enhance tensile performance,the in-situ ZrB2 particle/AA7085 composite sheets with thicknesses of 1,2,3,and 6 mm were *** as-cast grain size was significantly refined by the heterogeneous nucleus of the ZrB2 *** microstructure results show that severe hot deformation converts as-cast disordered microstructure into a sequential microstructure by crushing the remanent phases and matrix into a fiber *** the solid solution and aging heat treatment,the composite sheets exhibit largely recrystallized grains compared with partially recrystallized grains in the matrix sheets,and weak or even free texture exists in the *** grain size in the composite sheets decreases with the increase in thickness *** the thickness range of 1-3 mm,the composite sheets maintain a similar tensile per-formance as that in matrix sheets,while the strength and ductility in the 6-mm-thick composite sheet are improved.

关键词： Composite sheet Grain structure Texture Dislocation Strengthening

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Hydrologic Response to Future Climate Change in the Dulong-Irra-waddy River Basin Based on Coupled Model Intercomparison Project 6

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Chinese Geographical Science 2024年第2期34卷 294-310页

作者： XU Ziyue ma kai YUAN Xu HE Daming Institute of International Rivers and Eco-security Yunnan UniversityKunming 650500China Yunnan Key Laboratory of International Rivers and Transboundary Eco-security Kunming 650500China

Within the context of the Belt and Road Initiative(BRI)and the China-Myanmar Economic Corridor(CMEC),the Dulong-Ir-rawaddy(Ayeyarwady)River,an international river among China,India and Myanmar,plays a significant role as both a valuable hydro-power resource and an essential ecological ***,the water resources and security exhibit a high degree of vulnerabil-ity to climate change *** research evaluates climate impacts on the hydrology of the Dulong-Irrawaddy River Basin(DIRB)by using a physical-based hydrologic *** crafted future climate scenarios using the three latest global climate models(GCMs)from Coupled Model Intercomparison Project 6(CMIP6)under two shared socioeconomic pathways(SSP2-4.5 and SSP5-8.5)for the near(2025-2049),mid(2050-2074),and far future(2075-2099).The regional model using MIKE SHE based on historical hydrologic processes was developed to further project future streamflow,demonstrating reliable performance in streamflow simulations with a val-idation Nash-Sutcliffe Efficiency(NSE)of *** showed that climate change projections showed increases in the annual precip-itation and potential evapotranspiration(PET),with precipitation increasing by 11.3%and 26.1%,and PET increasing by 3.2%and 4.9%,respectively,by the end of the century under SSP2-4.5 and *** changes are projected to result in increased annual streamflow at all stations,notably at the basin’s outlet(Pyay station)compared to the baseline period(with an increase of 16.1%and 37.0%at the end of the 21st century under SSP2-4.5 and SSP5-8.5,respectively).Seasonal analysis for Pyay station forecasts an in-crease in dry-season streamflow by 31.3%-48.9%and 22.5%-76.3%under SSP2-4.5 and SSP5-8.5,respectively,and an increase in wet-season streamflow by 5.8%-12.6%and 2.8%-33.3%,***,the magnitude and frequency of flood events are pre-dicted to escalate,potentially impacting hydropower production and food security *** res

关键词： climate change hydrologic response Coupled Model Intercomparison Project 6(CMIP6) MIKE SHE(Système Hydrologique Europeén) Dulong-Irrawaddy River Basin

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Contrasts of bimodal tropical instability waves(TIWs)-induced wind stress perturbations in the Pacific Ocean among observations,ocean models,and coupled climate models

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Journal of Oceanology and Limnology 2024年第1期42卷 1-23页

作者： kai ma Chuanyu LIU Junli XU Fan WANG School of mathematics and Physics Research Institute for Mathematics and Interdisciplinary SciencesQingdao University of Science and TechnologyQingdao 266100China Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China Pilot National Laboratory for marine Science and Technology(Qingdao) Qingdao 266237China

The coupling between wind stress perturbations and sea surface temperature(SST)perturbations induced by tropical instability waves(TIWs)in the Pacific Ocean has been revealed previously and proven crucial to both the atmosphere and ***,an overlooked fact by previous studies is that the loosely defined“TIWs”actually consist of two modes,including the Yanai wave-based TIW on the equator(hereafter eTIW)and the Rossby wave-based TIW off the equator(hereafter vTIW).Hence,the individual feedbacks of the wind stress to the bimodal TIWs remain *** this study,individual coupling relationships are established for both eTIW and v TIW,including the relationship between the TIW-induced SST perturbations and two components of wind stress perturbations,and the relationship between the TIW-induced wind stress perturbation divergence(curl)and the downwind(crosswind)TIW-induced SST *** show that,due to different distributions of eTIW and vTIW,the coupling strength induced by the eTIW is stronger on the equator,and that by the vTIW is stronger off the *** results of any of eTIW and vTIW are higher than those of the loosely defined *** further investigated how well the coupling relationships remained in several widely recognized oceanic general circulation models and fully coupled climate ***,the coupling relationships cannot be well represented in most numerical ***,we confirmed that higher resolution usually corresponds to more accurate ***,the coupling models established in this study are complementary to previous research and can be used to refine the oceanic and coupled climate models.

关键词： bimodal tropical instability waves mesoscale air-sea interaction coupled models Yanai wave

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A new method for evaluating wedges of steel plates and strips

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Journal of Iron and Steel Research International 2024年第7期31卷 1719-1735页

作者： Xiao-bao ma Xiao-xin ma Tao Wang Zhong-kai Ren Yu-cheng Ren College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Ministry of Education Engineering Research Center of Advanced Metal Composite Forming Technology and Equipment Taiyuan University of TechnologyTaiyuan 030024ShanxiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment Taiyuan University of TechnologyTaiyuan 030024ShanxiChina China National Heavy machinery Research Institute Co. Ltd.Xi'an 710018ShaanxiChina Faculty of Mechanical Engineering Hebei University of ArchitectureZhangjiakou 075000HebeiChina

To overcome the inaccuracy problem of the traditional wedge evaluation of steel plates and strips caused by the ran-domness of the thicknesses of two local points and improve the reliability of the wedge index,the double-centroid method for the wedge evaluation was proposed,and a model based on the centroid theory was ***,an integral model for the discrete thickness values of the cross-section profiles was *** discussion focused on the distinct characteristics of the two-point method,asymmetric method,and double-centroid method in evaluating the asymmetric distribution of *** three methods were employed to evaluate the wedge values of both the theoretical and measured cross-sections of steel plates and strips,and the accuracies of three wedge evaluation models were analyzed and *** results showed that the double-centroid method objectively reflects the degree and variation characteristics of the wedge values of the cross-sections of steel plates and strips,and this method is feasible,reliable,and outstanding.

关键词： Steel plate and strip Wedge Two-point method Double-centroid method Reliability

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