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Robust Space-Time Adaptive Track-Before-Detect Algorithm Based on Persymmetry and Symmetric Spectrum

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Journal of Beijing Institute of Technology 2024年第1期33卷 65-74页

作者： Xiaojing Su da Xu Dongsheng zhu Zhixun Ma Institute of Acoustics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Underwater monopulse space-time adaptive track-before-detect method,which combines space-time adaptive detector(STAD)and the track-before-detect algorithm based on dynamic programming(DP-TBD),denoted as STAD-DP-TBD,can effectively detect low-speed weak ***,due to the complexity and variability of the underwater environment,it is difficult to obtain sufficient secondary data,resulting in a serious decline in the detection and tracking performance,and leading to poor robustness of the *** this paper,based on the adaptive matched filter(AMF)test and the RAO test,underwater monopulse AMF-DP-TBD algorithm and RAO-DP-TBD algorithm which incorporate persymmetry and symmetric spectrum,denoted as PSAMF-DP-TBD and PS-RAO-DP-TBD,are proposed and compared with the AMF-DP-TBD algorithm and RAO-DP-TBD algorithm based on persymmetry array,denoted as P-AMF-DP-TBD and *** simulation results show that the four methods can work normally with sufficient secondary data and slightly insufficient secondary data,but when the secondary data is severely insufficient,the P-AMF-DP-TBD and P-RAO-DP-TBD algorithms has failed while the PSAMF-DP-TBD and PS-RAO-DP-TBD algorithms still have good detection and tracking capabilities.

关键词： space-time adaptive detection track before detect robustness persymmetric property symmetric spectrum AMF test RAO test

Restraint effect of partition wall on the tunnel floor heave in layered rock mass

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Journal of Mountain Science 2024年第7期21卷 2462-2479页

作者： YANG Yunyun HUANG da ZHONG zhu LIU Yang PENG Jianbing School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China College of Geology Engineering and Geomatics Chang’an UniversityXi’an 710054China College of Civil Engineering&Architecture China Three Gorges UniversityYichang 443002China.

The presence of horizontal layered rocks in tunnel engineering significantly impacts the stability and strength of the surrounding rock mass,leading to floor heave in the *** study focused on preparing layered specimens of rock-like material with varying thickness to investigate the failure behaviors of tunnel *** results indicate that thin-layered rock mass exhibits weak interlayer bonding,causing rock layers near the surface to buckle and break upwards when subjected to horizontal *** an increase in the layer thickness,a transition in failure mode occurs from upward buckling to shear failure along the plane,leading to a noticeable reduction in floor heave *** primary cause of significant deformation in floor heave is upward buckling *** address this issue,the study proposes the installation of a partition wall in the middle of the floor to mitigate heave deformation of the rock *** results demonstrate that the partition wall has a considerable stabilizing effect on the floor,reducing the zone of buckling failure and minimizing floor heave *** is crucial for the partition wall to be sufficiently high to prevent buckling failure and ensure *** simulation calculations on an engineering example,it is confirmed that implementing a partition wall can effectively reduce floor heave and enhance the stability of tunnel floor.

关键词： Layered rock Floor heave Horizontal compression test Failure behavior Partition wall

Optical Transient Source AT2021lfa:A Possible“Dirty Fireball”

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Research in Astronomy and Astrophysics 2024年第4期24卷 124-133页

作者： Xue-Mei Ye da-Ming Wei Yi-Ming zhu Zhi-Ping Jin Key Laboratory of dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China

AT2021lfa,also known as ZTF21aayokph,was detected by the Zwicky Transient Facility on 2021 May 4,a 05:34:48 ***-up observations were conducted using a range of ground-based optical telescopes,as wel as Swift/XRT and VLA ***2021lfa is classified as an“orphan afterglow”candidate due to its rapid flux decline and its reddened color(g-r=0.17±0.14 mag).For an optical transient source without promp gamma-ray detection,one key point is to determine its burst *** we measure the burst time through fitting the initial bump feature of AT2021lfa and obtain its burst time as 2021 May 3,at 22:09:50 *** afterglowpy,we model the multi-band afterglow of AT2021lfa and find that the sta.da.d model canno reproduce the late radio observations *** that the microphysical parameters ε_(e),ε_(B)(the energy fraction given to electrons and magnetic field),andξN(the fraction of accelerated electrons)may vary with time we then model the afterglow of AT2021lfa taking into account the temporal evolution of the physical parameters ε_(e),ε^(B),and ξ_(N) and find in this case the multi-wavelength observations can be reproduced *** initial Lorentz factor of AT2021lfa can be estimated from the peak time of the early afterglow,which yields a value of about 18 suggesting that AT2021lfa should be classified as a“dirty fireball.”From the upper limit for the prompt emission energy of AT2021lfa,we obtain that the radiation efficiency is less than 0.02%,which is much smaller than that of ordinary gamma-ray bursts(GRBs).It is also interesting that the fitted values of jet angle and viewing angle are very large,θ_(c)~0.66 rad,θ_(v)~0.53 rad,which may lead to the low Lorentz factor and radiation *** compared with GRB afterglow samples,it is evident that the onset bump timescale of AT2021lfa satisfies the empirical relationships observed in GRB ***,the luminosity of AT2021lfa falls within the range of observations for GRB samples;howeve

关键词： gamma-rays:ISM methods:numerical radiation mechanisms:non-thermal

The genesis and resource potential of gold deposits in the Liaodong Peninsula

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Science China Earth Sciences 2024年第3期67卷 657-672页

作者： Rixiang zhu Jin-Hui YANG Gongwen WANG Qingdong ZENG Guoqiang XUE Tao XU Xinghui LI Peng ZHANG da LEI Guang zhu State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Shenyang Center China Geological SurveyShenyang 110034China School of Resources and Environmental Engineering Hefei University of TechnologyHefei 230009China

Plenty of gold deposits related to Late Mesozoic craton destruction are widely distributed in eastern North China Craton. However, significant differences in research degrees, ore-forming characteristics, and proven reserves exist among different regions in the North China Craton. The Liaodong Peninsula has similar regional geological characteristics to those of the Jiaodong Peninsula, with both experiencing craton destruction during Late Mesozoic, but the two areas have substantial differences in terms of gold mineralization and the proven gold resources. Based on regional geology, Mesozoic magmatictectonic evolution and ore geology, combined with integrated geophysical exploration and big data AI resource prediction, in this paper, we propose that the ore-forming materials of Late Mesozoic gold deposits in Liaodong were mainly originated from mantle-derived melts and/or fluids induced by craton destruction. The gold deposits were primarily controlled by NE-NNEtrending faults, mainly classified as fracture-controlled altered rock-type and sulfide-bearing quartz vein-type. Moreover, our study predicts that the Yalu River fault zone and its related secondary faults, as well as the periphery and deeper parts of known goldfields, are the important regions for future gold resource exploration. The Yalu River metallogenic belt has an enormous potential for gold resources, and the Liaodong Peninsula has a potential to add thousands of tons of gold resources.

关键词： Liaodong Peninsula Gold deposit Integrated geophysical exploration Prospecting potential Direction for prospecting breakthroughs

The BTB/TAZ domain-containing protein CmBT1-mediated CmANR1 ubiquitination negatively regulates root development in chrysanthemum

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Journal of Integrative Plant Biology 2024年第2期66卷 285-299页

作者： Lian-da Du Zhang-Ji Guan Yan-Hong Liu Hui-Dong zhu Quan Sun da-Gang Hu Cui-Hui Sun Shandong Collaborative Innovation Center of Fruit&Vegetable Quality and Efficient Production College of Horticulture Science and EngineeringShandong Agricultural UniversityTaian 271018China

Roots are fundamental for plants to adapt to variable environmental *** development of a robust root system is orchestrated by numerous genetic determinants and,among them,the MADS-box gene ANR1 has garnered substantial *** research has demonstrated that,in chrysanthemum,CmANR1positively regulates root system ***,the upstream regulators involved in the CmANR1-mediated regulation of root development remain *** this study,we successfully identified bric-a-brac,tramtrack and broad(BTB)and transcription adapter putative zinc finger(TAZ)domain protein CmBT1 as the interacting partner of CmANR1 through a yeasttwo-hybrid(Y2H)screening ***,we validated this physical interaction through bimolecular fluorescence complementation and pull-down *** assays revealed that CmBT1 exerted a negative influence on root development in *** both in vitro and in vivo assays,it was evident that CmBT1mediated the ubiquitination of CmANR1 through the ubiquitin/26S proteasome *** ubiquitination subsequently led to the degradation of the CmANR1 protein and a reduction in the transcription of CmANR1-targeted gene CmPIN2,which was crucial for root development in *** analysis suggested that CmBT1 modulated root development,at least in part,by regulating the level of CmANR1 ***,these findings shed new light on the regulatory role of CmBT1 in degrading CmANR1 through ubiquitination,thereby repressing the expression of its targeted gene and inhibiting root development in chrysanthemum.

关键词： chrysanthemum MADS-box transcription factor root development

data-driven casting defect prediction model for sand casting based on random forest classification algorithm

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China Foundry 2024年第2期21卷 137-146页

作者： Bang Guan Dong-hong Wang da Shu Shou-qin zhu Xiao-yuan Ji Bao-de Sun Shanghai Key Lab of Advanced High-Temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Lab of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China Hefei Casting and Forging Factory of Anhui Heli Co. LtdHefei 230000China State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan 430074China

The complex sand-casting process combined with the interactions between process parameters makes it difficult to control the casting quality,resulting in a high scrap rate.A strategy based on a.da.a-driven model was proposed to reduce casting defects and improve production efficiency,which includes the random forest(RF)classification model,the feature importance analysis,and the process parameters optimization with Monte Carlo *** collected data includes four types of defects and corresponding process parameters were used to construct the RF *** results show a recall rate above 90% for all *** Gini Index was used to assess the importance of the process parameters in the formation of various defects in the RF ***,the classification model was applied to different production conditions for quality *** the case of process parameters optimization for gas porosity defects,this model serves as an experimental process in the Monte Carlo method to estimate a better temperature *** prediction model,when applied to the factory,greatly improved the efficiency of defect *** show that the scrap rate decreased from 10.16% to 6.68%.

关键词： sand casting process data-driven method classification model quality prediction feature importance

Critical approaches in the catalytic transformation of sugar isomerization and epimerization after Fischer-History,challenges,and prospects

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Green Energy & Environment 2024年第3期9卷 435-453页

作者： da-Ming Gao Xun Zhang Haichao Liu Hidemi Fujino Tingzhou Lei Fuan Sun Jie zhu Taoli Huhe National-local Joint Engineering Research Center of Biomass Refine and High-Quality Utilization Changzhou UniversityChangzhou213164China Institute of Urban and Rural Mining Research Changzhou UniversityChangzhou213164China Changzhou Key Laboratory of Biomass Green Safe&High Value UtilizationChangzhou UniversityChangzhou213164China Beijing National Laboratory for Molecular Science College of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China Department of Rehabilitation Science Kobe University Graduate School of Health SciencesKobe654-0142Japan

The transformation of aldose to ketose or common sugars into rare saccharides,including rare ketoses and aldoses,is of great value and interest to the food industry and for saccharidic biomass utilization,medicine,and the synthesis of ***,high-fructose corn syrup(HFCS)is industrially produced in more than 10 million tons annually using immobilized glucose *** low-calorie saccharides such as tagatose and psicose,which are becoming popular sweeteners,have also been produced on a pilot scale in order to replace sucrose and ***,current catalysts and catalytic processes are still difficult to utilize in biomass conversion and also have strong substrate dependence in producing high-value,rare *** the specific reaction properties of saccharides and catalysts,since the pioneering discovery by Fischer,various catalysts and catalytic systems have been discovered or developed in attempts to extend the reaction pathways,improve the reaction efficiency,and to potentially produce commercial *** this review,we trace the history of sugar isomerization/epimerization reactions and summarize the important breakthroughs for each reaction as well as the difficulties that remain unresolved to date.

关键词： Rare sugars Isomerization Ketonization Epimerization Catalytic transformation

A new two-step variational model for multiplicative noise removal with applications to texture images

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 486-501页

作者： ZHANG Long-hui YAO Wen-juan SHI Sheng-zhu GUO Zhi-chang ZHANG da-zhi School of Mathematics Harbin Institute of TechnologyHarbin 150001China

Multiplicative noise removal problems have attracted much attention in recent *** additive noise,multiplicative noise destroys almost all information of the original image,especially for texture *** by the TV-Stokes model,we propose a new two-step variational model to denoise the texture images corrupted by multiplicative noise with a good geometry explanation in this *** the first step,we convert the multiplicative denoising problem into an additive one by the logarithm transform and propagate the isophote directions in the tangential field *** the isophote directions are constructed,an image is restored to fit the constructed directions in the second *** existence and uniqueness of the solution to the variational problems are *** these two steps,we use the gradient descent method and construct finite difference schemes to solve the ***,the augmented Lagrangian method and the fast Fourier transform are adopted to accelerate the *** results show that the proposed model can remove the multiplicative noise efficiently and protect the texture well.

关键词： multiplicative noise removal texture images total variation two-step variational method aug-mented Lagrangian method

ROR2 promotes invasion and chemoresistance of triple-negative breast cancer cells by activating PI3K/AKT/mTOR signaling

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Oncology Research 2024年第7期32卷 1209-1219页

作者： XIa.da.HAN GE JUNFENG SHI CHUNHUA zhu GUOzhu WANG YUAN FANG JIN XU Department of Breast and Thyroid Nanjing First HospitalNanjing Medical UniversityNanjingChina Department of General Surgery The First Affiliated Hospital of Nanjing Medical UniversityNanjingChina Department of Oncology Nanjing First HospitalNanjing Medical UniversityNanjingChina Department of Pathology Nanjing First HospitalNanjing Medical UniversityNanjingChina

Objective:This study aimed to investigate the role of receptor tyrosine kinase-like orphan receptor 2(ROR2)in triple-negative breast cancer(TNBC).Methods:ROR2 expression in primary TNBC and metastatic TNBC tissues was analyzed by immunohistochemical staining and ***2 expression in TNBC cell lines was detected by PCR and Western blot *** migration,invasion and chemosensitivity of TNBC cells with overexpression or knockdown of ROR2 were ***:ROR2 expression was high in metastatic TNBC ***2 knockdown suppressed the migration,invasion and chemoresistance of TNBC ***2 overexpression in Mda-MB-435 cells promoted the migration,invasion,and ***,ROR2 knockdown in HC1599 and Mda-MB-435 adriamycin-resistant cells enhanced chemosensitivity to ***2 could activate PI3K/AKT/mTOR signaling in TNBC ***:ROR2 is upregulated and promotes metastatic phenotypes of TNBC by activating PI3K/AKT/mTOR signaling.

关键词： Receptor tyrosine kinase-like orphan receptor 2 Triplet-negative breast cancer Proliferation Apoptosis PI3K/AKT/mTOR signaling Metastasis