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On Asymptotically Isometric Copies of l~β(0 < β < 1)

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Journal of Mathematical Research and Exposition 2010年第6期30卷 1032-1038页

作者： chen ZHI mei mei SONG Department of Mathematics Tianjin University of Technology Tianjin 300384 P. R. China

We get the characterizations of the family of all nonnegative, subadditive,β-absolutely homogeneous and continuous functionals defined on X, when the ;3-normed space X contains an asymptotically isometric copy of l^β. Moreover, it is proved that if a closed bounded β-convex subset K of a β-normed space contains an asymptotically isometric β-basis, then K contains a closed β-convex subset C which fails the fixed point property.

关键词： asymptotically isometric copy β-normed space β-absolutely homogeneous

Asymptotically Isometric Copy of l~β(0<β<1) in Spacesof Bounded Linear Operators

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Journal of Mathematical Research and Exposition 2011年第3期31卷 562-566页

作者： chen ZHI mei mei SONG Department of Mathematics Tianjin University of Technology Tianjin 300384 P. R. China

Assume X is a normed space,every x ＊ ∈ S（X＊） can reach its norm at some point in B（X）,and Y is a β-normed *** there is a quotient space of Y which is asymptotically isometric to l β,then L（X,Y） contains an asymptotically isometric copy of l β.Some sufficient conditions are given under which L（X,Y） fails to have the fixed point property for nonexpansive mappings on closed bounded β-convex subsets of L（X,Y）.

关键词： asymptotically isometric copy space of bounded linear operators quotient space fixed point property.

Microstructural evolution during the progressive transformation-induced plasticity effect in a Fe-0.1C-5Mnmedium manganese steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 369-379页

作者： mei Zhang Wenhao Li Yangfei chen Yang Jiang Xiaofei Guo Han Dong School of Materials Science and Engineering Shanghai UniversityShanghai 200444China State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China

The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile ***-situ observations under scanning electron microscopy,transmission electron microscopy,and X-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation *** findings were discussed with the local strain measurements via digital image *** results indicated that Lüders band formation in the steel was limited to 1.5%strain,which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite(RA),which led to localized stress concentrations and strain hardening and further retardation of *** small-sized RA exhibited high stability and progressively transformed into martensite and contributed to a stably extended Portevin-Le Chatelier *** volume fraction of RA gradually decreased from 26.8%to 8.2%prior to *** the late deformation stage,fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase.

关键词： medium-Mn steel retained austenite progressive transformation-induced plasticity effect local strain fracture initiation

Asymptotically Isometric Copy of l~β(0

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Journal of Mathematical Research with Applications 2011年第3期 562-566页

作者： chen ZHI,mei mei SONG Department of Mathematics,Tianjin University of Technology,Tianjin 300384,P.R.China

Assume X is a normed space,every x * ∈ S(X*) can reach its norm at some point in B(X),and Y is a β-normed *** there is a quotient space of Y which is asymptotically isometric to l β,then L(X,Y) contains an asymptotically isometric copy of l β.Some sufficient conditions are given under which L(X,Y) fails to have the fixed point property for nonexpansive mappings on closed bounded β-convex subsets of L(X,Y).

关键词： asymptotically isometric copy space of bounded linear operators quotient space fixed point property.

Disentangling microbial coupled fillers mechanisms for the permeable layer optimization process in multi-soil-layering systems

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Journal of Environmental Sciences 2025年第1期147卷 538-549页

作者： Daxin Sun Chuanping Feng Yongheng Zhan Bingbing Deng Duoduo mei Nan chen Weiwu Hu School of Water Resources and Environment MOE Key Laboratory of Groundwater Circulation and Environmental EvolutionChina University of Geosciences(Beijing)Beijing 100083China Journal Center China University of Geosciences(Beijing)Beijing 100083China

Themulti-soil-layering(MSL)systems is an emerging solution for environmentally-friendly and cost-effective treatment of decentralized rural domestic ***,the role of the seemingly simple permeable layer has been overlooked,potentially holding the breakthroughs or directions to addressing suboptimal nitrogen removal performance in MSL *** this paper,the mechanism among diverse substrates(zeolite,green zeolite and biological ceramsite)coupled microorganisms in different systems(activated bacterial powder and activated sludge)for rural domestic wastewater purification was *** removal efficiencies performed by zeolite coupled with microorganisms within 3 days were 93.8%for COD,97.1%for TP,and 98.8%for NH_(4)^(+)-***,activated sludge showed better nitrification and comprehensive performance than specialized nitrifying bacteria *** attained an impressive 89.4%NH4+-N desorption efficiency,with a substantive fraction of NH_(4)^(+)-N manifesting as exchanged ***-throughput 16S rRNA gene sequencing revealed that aerobic and parthenogenetic anaerobic bacteria dominated the reactor,with anaerobic bacteria conspicuously *** the heterotrophic nitrificationaerobic denitrification(HN-AD)process was significant,with the presence of denitrifying phosphorus-accumulating organisms(DPAOs)for simultaneous nitrogen and phosphorus *** study not only raises awareness about the importance of the permeable layer and enhances comprehension of the HN-AD mechanism in MSL systems,but also provides valuable insights for optimizing MSL system construction,operation,and rural domestic wastewater treatment.

关键词： Rural domestic wastewater Multi-soil-layering(MSL)system Heterotrophic nitrification-aerobic denitrification(HN-AD) Nitrogen and phosphorus removal Microbial evolution

MixerKT:A Knowledge Tracing Model Based on Pure MLP Architecture

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Computers, Materials & Continua 2025年第1期82卷 485-498页

作者： Jun Wang Mingjie Wang Zijie Li Ken chen Jiatian mei Shu Zhang Key Laboratory of Education Informatization for Nationalities Ministry of EducationYunnan Normal UniversityKunming650000China Yunnan Key Laboratory of Smart Education Yunnan Normal UniversityKunming650000China

In the field of intelligent education,the integration of artificial intelligence,especially deep learning technologies,has garnered significant *** tracing(KT)plays a pivotal role in this field by predicting students’future performance through the analysis of historical interaction data,thereby assisting educators in evaluating knowledgemastery and tailoring instructional *** knowledge tracingmethods,largely based on Recurrent Neural Networks(RNNs)and Transformer models,primarily focus on capturing long-term interaction patterns in sequential ***,these models may neglect crucial short-term dynamics and other relevant *** paper introduces a novel approach to knowledge tracing by leveraging a pure Multilayer Perceptron(MLP)*** proposeMixerKT,a knowledge tracing model based on theHyperMixer framework,which uniquely integrates global and localMixer feature *** architecture enables more effective extraction of both long-terminteraction trends and recent learning behaviors,addressing limitations in currentmodels thatmay overlook these key *** evaluations on twowidely-used datasets,ASSIS Tments2009 and Algebra2005,demonstrate that MixerKT consistently outperforms several state-of-the-art models,including DKT,SAKT,and Separated Self-Attentive Neural Knowledge Tracing(SAINT).Specifically,MixerKT achieves higher prediction accuracy,highlighting its effectiveness in capturing the nuances of learners’knowledge *** results indicate that our model provides a more comprehensive representation of student learning patterns,enhancing the ability to predict future performance with greater precision.

关键词： Knowledge tracing multilayer perceptron channel mixer sequence mixer

Retrospective analysis of pathological types and imaging features in pancreatic cancer: A comprehensive study

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 121-129页

作者： Yang-Gang Luo mei Wu Hong-Guang chen Pathology Department Xuanhan County People’s HospitalDazhou 636150Sichuan ProvinceChina

BACKGROUND Pancreatic cancer remains one of the most lethal malignancies worldwide,with a poor prognosis often attributed to late *** the correlation between pathological type and imaging features is crucial for early detection and appropriate treatment *** To retrospectively analyze the relationship between different pathological types of pancreatic cancer and their corresponding imaging *** We retrospectively analyzed the data of 500 patients diagnosed with pancreatic cancer between January 2010 and December 2020 at our *** types were determined by histopathological examination of the surgical spe-cimens or biopsy *** imaging features were assessed using computed tomography,magnetic resonance imaging,and endoscopic *** analyses were performed to identify significant associations between pathological types and specific imaging *** There were 320(64%)cases of pancreatic ductal adenocarcinoma,75(15%)of intraductal papillary mucinous neoplasms,50(10%)of neuroendocrine tumors,and 55(11%)of other rare *** imaging features were identified in each pathological *** ductal adenocarcinoma typically presents as a hypodense mass with poorly defined borders on computed tomography,whereas intraductal papillary mucinous neoplasms present as characteristic cystic lesions with mural *** tumors often appear as hypervascular lesions in contrast-enhanced *** analysis revealed significant correlations between specific imaging features and pathological types(P<0.001).CONCLUSION This study demonstrated a strong association between the pathological types of pancreatic cancer and imaging *** findings can enhance the accuracy of noninvasive diagnosis and guide personalized treatment approaches.

关键词： Pancreatic cancer Pathological types Imaging features Retrospective analysis Diagnostic accuracy

Preparation of Low Ratio Magnesium Ccement by Acid Leaching Treatment of Boron Mud

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 120-129页

作者： YANG mei ZHANG Mingzhe chen Hao School of Materials Science and Engineering Shenyang Jianzhu UniversityShenyang 110168China School of Physical Science and Technology Shenyang Normal UniversityShenyang 110168China

The effects of liquid-solid ratio and reaction time on the leaching rate of magnesium at room temperature were investigated,as well as the effects of the molar ratio of MgO/MgCl_(2),the amount of water added,and the amount of acid-impregnated slag dosed on the compressive strength and water resistance of *** results showed that the magnesium element in the boron mud could be maximally leached under the conditions of 1:1 concentration of hydrochloric acid at room temperature,liquid-solid ratio of 2.5 mL·g^(-1),and reaction time of 5 h,and the main products were amorphous SiO_(2) as well as a small amount of magnesium olivine which had not been completely *** LR-MOC prepared using the acid-soaked mixture could reach a softening coefficient of 0.85 for 28 d of water immersion when the molar ratio of MgO/MgCl_(2) was 2.2,the amount of water added was 0 g,and the acid-soaked slag dosing was 40 wt%,which also led to an appreciable late-strength,with an increase of 19.4%in compressive strength at 28 d compared to that at 7 *** previous studies,LR-MOC prepared in this way has a final strength phase that is not the more easily hydrolysed 3-phase but the lath-like *** this phenomenon,we analyzed the mechanism and found that,during the acid leaching process,a part of amorphous SiO_(2) dissolved in the acid leaching solution formed a silica sol,in which Mg^(2+)played a bridging role to make the silica sol more *** the addition and hydrolysis of MgO,the silica sol gel coagulation slows down,providing a capping layer to inhibit the hydrolysis of the 5-phase crystals and providing some strength after *** amorphous SiO_(2) in the other part of the acid-impregnated slag generated M-S-H gel with Mg^(2+)and OH-,which synergised with the dense structure composed of interlocking crystals to improve the water resistance of LR-MOC.

关键词： boron mud magnesium chloride-oxygen cement acid immersion water resistance silica sol

Modeling and control of a rigid-flexible coupling robot for narrow space manipulations

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Science China(Technological Sciences) 2025年第2期68卷 136-152页

作者： Kuangda chen Huan ZHAO Jiexin ZHANG mei FENG Yiwei WANG Jinliang WANG Han DING State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China Key Laboratory of CNC Equipment Reliability Ministry of EducationJilin UniversityChangchun 130021China School of Medical Equipment Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China

Narrow space manipulations are crucial for equipment maintenance,as they eliminate the need for disassembly,thus reducing costs and increasing ***-driven flexible robots possess exceptional capabilities in maneuvering through narrow spaces,thanks to their interaction compliance and distal ***,their inherent low stiffness causes a decline in the location accuracy of the robot and could even lead to manipulation *** address this challenge,this paper proposes a novel type of rigid-flexible coupling robot,which increases the stiffness of the robot while ensuring the reachability within a narrow *** achieve high-accuracy location in a narrow space,kinematic and control methods are ***,the robot forward kinematics are uniformly represented,and the closed-form inverse kinematics solution is ***,in cases where the robotʼs structure fails to align with Pieperʼs solution,a two-stage search strategy is utilized to solve the inverse kinematics,resulting in a high success rate of 99.1%.Based on the proposed kinematics,a rigid-dominated control method is then proposed to facilitate localization and pose alignment of target objects in narrow *** practical comparative experiments show that the proposed robot has the capability of high accuracy control in narrow spaces.

关键词： narrow space manipulation rigid-flexible coupling robot kinematics rigid-dominated control

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