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Differentially private SGD with random features

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Applied Mathematics(A j.urnal of Chinese Universities) 2024年第1期39卷 1-23页

作者： wang Yi-guang GUO Zheng-chu Polytechnic Institute of Zhej.ang University Zhejiang UniversityHangzhou 310015China School of Mathematical Sciences Zhejiang UniversityHangzhou 310058China

In the realm of large-scale machine learning,it is crucial to explore methods for reducing computational complexity and memory demands while maintaining generalization ***,since the collected data may contain some sensitive information,it is also of great significance to study privacy-preserving machine learning *** paper focuses on the performance of the differentially private stochastic gradient descent(SGD)algorithm based on random *** begin,the algorithm maps the original data into a lowdimensional space,thereby avoiding the traditional kernel method for large-scale data storage ***,the algorithm iteratively optimizes parameters using the stochastic gradient descent ***,the output perturbation mechanism is employed to introduce random noise,ensuring algorithmic *** prove that the proposed algorithm satisfies the differential privacy while achieving fast convergence rates under some mild conditions.

关键词： learning theory differential privacy stochastic gradient descent random features reproducing kernel Hilbert spaces

Cr^(3+) activated Na_(3)RESi_(3)O_(9)(RE=Y,Lu,Sc) silicate broadband near-infrared phosphors for luminescence towards NIR-Ⅱ region via a multi-site occupancy strategy

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j.urnal of Rare Earths 2024年第8期42卷 1447-1457,I0002页

作者： j.antong wang Changshuai Gong Sihan Yang Qi Zhu Xuej.ao wang j.-guang Li College of Chemistry and Materials Engineering Bohai UniversityJinzhou121007China Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China Research Center for Electronic and Optical Materials National Institute for Materials ScienceTsukubaIbaraki 305-0044Japan

Phosphor-converted near-infrared light-emitting diodes(NIR pc-LEDs) are finding applications in various fields including food quality analysis,biomedical imaging,night vision,and *** crucial factor in the development of NIR pc-LEDs devices lies in the advancement of high-performance broadband NIR phosphors,In this work,novel Cr^(3+)-activated silicate phosphors NaRESi_(3)O_(9)(RE=Y,Lu,Sc) are *** silicate has a special 3D network structure in which RE has four different sites,forming four octahedrons and providing suitable occupation sites for Cr^(3+).The phosphors demonstrate a wide emission spectrum ranging from 750 to 1450 nm when excited by light at 468 *** full width at half maximum(FWHM),which benefits from the presence of Cr^(3+)ions occupying multiple sites,is measured to be 203 ***,the strongest emission peak is observed at a longer wavelength of 984 nm compared to most other systems activated by Cr^(3+).The Na_(3)ScSi_(3)O_(9) lattice provides a weak crystal field(Dq/B=1.97) and weak phonon-photon coupling for Cr^(3+),and the integrated emission intensity of Na_(3)ScSi_(3)O_(9):0,03Cr^(3+)is 4.66 times stronger than that of Na_(3)YSi_(3)O_(9):0.03Cr^(3+).

关键词： Rare earths Broadband near-infrared Silicate Photoluminescence Cr^(3+)

Kinematic calibration method with high measurement efficiency and robust identification for hybrid machine tools

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Chinese j.urnal of Aeronautics 2024年第3期37卷 468-482页

作者： Liping wang Mengyu LI guang YU Weitao LI Xiangyu KONG State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Beij.ng Key Laboratory of Precision/Ultra-precision Manufacturing Equipment and Control Beijing 100084China

Geometric error is the main factor affecting the machining accuracy of hybrid machine *** calibration is an effective way to improve the geometric accuracy of hybrid machine *** necessity to measure both position and orientation at each pose,as well as the instability of identification in case of incomplete measurements,severely affects the application of traditional calibration *** this study,a kinematic calibration method with high measurement efficiency and robust identification is proposed to improve the kinematic accuracy of a five-axis hybrid machine ***,the configuration is introduced,and an error model is ***,by investigating the mechanism error characteristics,a measurement scheme that only requires tool centre point position error measurement and one alignment operation is ***,by analysing the effects of unmeasured degrees of freedom(DOFs)on other DOFs,an improved nonlinear least squares method based on virtual measurement values is proposed to achieve stable parameter identification in case of incomplete measurement,without introducing additional ***,the proposed calibration method is verified through simulations and *** proposed method can efficiently accomplish the kinematic calibration of the hybrid machine *** accuracy of the hybrid machine tool is significantly improved after calibration,satisfying actual aerospace machining requirements.

关键词： Hybrid machine tool Calibration Measurement scheme Improved nonlinear least squares method Virtual measurement values

Effect of MgO-Cr_(2)O_(3) and Mg0-MgAl_(2)0_(4)-based refractories on refractory-steel interface reaction and cleanliness of pipeline steel

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j.urnal of Iron and Steel Research International 2024年第4期31卷 849-860页

作者： guang-mei Yang Cheng Yuan Chang Liu Qiang wang guang-qiang Li Yong-shun Zou Ao Huang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina

The interaction of MgO-MgAl_(2)O_(4)-based and MgO-Cr_(2)O_(3)-based refractories with X70 molten steel was studied by immersion experiments at 1560℃.The effects of immersion time(30 and 60 min)on the contents of total oxygen(TO),Al,Nb,Si,Mn,and Cr as well as the composition,number density,and size distribution of inclusions in the molten steel were *** influence of the penetration and erosion degree of the molten steel to the refractory on the steel-refractory interface layer was *** results show that,at 1560℃,the MgO-MgAl_(2)O_(4)-based refractory can better control the contents of TO and the composition of molten steel compared with the MgO-Cr_(2)O_(3)-based *** TO content is only 16×10^(-4) wt.%in the molten steel after reacted with the Mg0-MgAl_(2)O_(4)-based refractory at the end point of refining,4 accounting for 11.5%of that reacted with the MgO-Cr_(2)O_(3)-based refractory(139×10^(-4) wt.%).The number density of inclusions is only 14 mm^(-2),and the average size ofinclusions is only 1.31μm,with thelargest proportion of inclusions in 1-2μm(70%).The Al_(2)O_(3)-MnS-CaO complex inclusions in the original steel changed to complex inclusions dominated by Cr-Nb-Mn-S-O and ***_(2)O_(3),corresponding to the MgO-Cr_(2)O_(3)-based and MgO-MgAl_(2)O_(4)-based refractories,*** ***_(2)O_(3) layer was formed at the reaction interface between MgO-MgAl_(2)O_(4)-based refractory and molten steel,which is helpful to restrict the erosion of refractories and the pollution of molten *** damage mechanism of the MgO-Cr_(2)O_(3)-based refractory is mainly permeation and chemical reaction,while the damage of the MgO-MgAl_(2)O_(4)-based refractory is mainlyscouring erosion.

关键词： MgO-Cr_(2)O_(3)-based refractory MgO-MgAl O_(4)-based refractory Nonmetallic inclusion Erosion interface layer Steel penetration

Integrating theory with the nanoreactor concept to synthesize hollow carbon sphere-encapsulated PtNi alloys for enhanced H_(2) generation

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Carbon Energy 2024年第7期6卷 150-162页

作者： Yufeng Wu Minwei Song Ziyi Zhao guang-Hui wang Changlong wang Didier Astruc Institute of Circular Economy Faculty of Materials and ManufacturingBeijing University of TechnologyBeijingChina Key Laboratory of Biofuels Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdaoChina ISM UMR CNRS N°5255Universitéde BordeauxTalence CedexFrance

The rational design of efficient bimetallic nanoparticle(NP)catalysts is challenging due to the lack of theoretical understanding of active components and insights into the mechanisms of a specific ***,we report the rational design of nanoreactors comprising hollow carbon sphere-confined PtNi bimetallic NPs(PtNi@HCS)as highly efficient catalysts for hydrogen generation via ammonia borane hydrolysis in *** both density functional theory calculations and molecular dynamics simulations,the effects of an active PtNi combination and the critical synergistic role of a hollow carbon shell on the molecule diffusion adsorption behaviors are *** isotope effects and theoretical calculations allow the clarification of the mechanism,with oxidative addition of an O-H bond of water to the catalyst surface being the rate-determining *** remarkable catalytic activity of the PtNi@HCS nanoreactor was also utilized for successful tandem catalytic hydrogenation reactions,using in situ-generated H_(2) from ammonia borane with high *** concerted design,theoretical calculations,and experimental work presented here shed light on the rational elaboration of efficient nanocatalysts and contribute to the establishment of a circular carbon economy using green hydrogen.

关键词： ammonia borane hydrogen nanoalloy nanoreactor solid catalyst

Therapeutic potential of targeting protein tyrosine phosphatases in liver diseases

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Acta Pharmaceutica Sinica B 2024年第8期14卷 3295-3311页

作者： Ao wang Yi Zhang Xinting Lv guang Liang Department of Pharmacy and Institute of Inflammation Zhejiang Provincial Affiliated People’s HospitalHangzhou Medical CollegeHangzhou 310014China Key Laboratory of Natural Medicines of the Changbai Mountain Ministry of EducationYanbian UniversityYanji 133002China Chemical Biology Research Center School of Pharmaceutical SciencesWenzhou Medical UniversityWenzhou 325035China

Protein tyrosine phosphorylation is a post-translational modification that regulates protein structure to modulate demic organisms’homeostasis and *** physiological process is regulated by two enzyme families,protein tyrosine kinases(PTKs)and protein tyrosine phosphatases(PTPs).As an important regulator of protein function,PTPs are indispensable for maintaining cell intrinsic physiology in different systems,as well as liver physiological and pathological *** of PTPs has been implicated in multiple liver-related diseases,including chronic liver diseases(CLDs),hepatocellular carcinoma(HCC),and liver inj.ry,and several PTPs are being studied as drug therapeutic ***,given the regulatory role of PTPs in diverse liver diseases,a collated review of their function and mechanism is ***,based on the current research status of targeted therapy,we emphasize the inclusion of several PTP members that are clinically significant in the development and progression of liver *** an emerging breakthrough direction in the treatment of liver diseases,this review summarizes the research status of PTP-targeting compounds in liver diseases to illustrate their potential in clinical ***,this review aims to support the development of novel PTP-based treatment pathways for liver diseases.

关键词： Tyrosine phosphorylation PTPs Signal transduction CLDs HCC Allosteric inhibitor PROTACs Drug development

j.anpi Qinghua Formula Alleviates Diabetic Myocardial Inj.ry Through Inhibiting j.nB/c-Fos Expression

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Current Medical Science 2024年第1期44卷 144-155页

作者： Lin wang Qing-guang CHEN Hao LU Department of Endocrinology Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Department of Traditional Chinese Medicine Naval Medical UniversityShanghai 200433China

Obj.ctive Diabetic cardiomyopathy(DCM)represents a substantial risk factor for heart failure and increased mortality in individuals afflicted with diabetes mellitus(DM).DCM typically manifests as myocardial fibrosis,myocardial hypertrophy,and impaired left ventricular diastolic *** the clinical utility of the j.anpi Qinghua(j.QH)formula has been established in treating diabetes and insulin resistance,its potential efficacy in alleviating diabetic cardiomyopathy remains *** study aims to investigate the impact and underlying molecular mechanisms of the j.QH formula(j.QHF)in ameliorating myocardial inj.ry in nonobese diabetic rats,specifically focusing on apoptosis and *** Wistar rats were assigned as the normal control group(CON),while Goto-Kakizaki(GK)rats were randomly divided into three groups:DM,DM treated with the j.QHF,and DM treated with metformin(MET).Following a 4-week treatment regimen,various biochemical markers related to glucose metabolism,cardiac function,cardiac morphology,and myocardial ultrastructure in GK rats were *** sequencing was utilized to analyze differential gene expression and identify potential therapeutic *** vitro experiments involved high glucose to induce apoptosis and inflammation in H9c2 *** viability was evaluated using CCK-8 assay,apoptosis was monitored via flow cytometry,and the production of inflammatory cytokines was measured using quantitative real-time PCR(qPCR)and *** expression levels were determined by Western blotting *** investigation also incorporated the use of MAPK inhibitors to further elucidate the mechanism at both the transcriptional and protein *** The j.QHF group exhibited significant reductions in interventricular septal thickness at end-systole(IVSs)and left ventricular internal diameter at end-systole and end-diastole(LVIDs and LVIDd).j.QHF effectively suppressed high glucose-induced activation of IL-1βand caspase 3 in

关键词： j.anpi Qinghua formula diabetic cardiomyopathy AP-1 transcription factor apoptosis inflammation

A model reduction approach for discrete-time linear time-variant systems with delayed inputs

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Science China(Information Sciences) 2024年第4期67卷 197-217页

作者： Ai-Guo WU guang-Ren DUAN Yu wang j.e ZHANG School of Mechanical Engineering and Automation Harbin Institute of Technology(Shenzhen) HIT Wuhu Robot Technology Research Institute Center for Control Science and Technology Southern University of Science and Technology

A model reduction approach is presented for discrete-time linear time-variant input-delayed systems. According to this proposed approach, a dynamical variable is constructed by taking advantage of the current state and historical information of input. It is revealed that the behavior of this dynamical variable is governed by a discrete-time linear delay-free system. It is worth noting that the presented variable transformation does not require the system matrix to be invertible. Based on the reduced delay-free models,stabilizing control laws can be easily obtained for the original delayed system. For the case with a single input delay, the constructed variable is an exact prediction for the future state, and thus the stabilizing control law could be designed by replacing the future state with its prediction. Finally, three discrete-time periodic systems with delayed input are employed to illustrate how to utilize the presented model reduction approaches.

关键词： reduction approach predictor-based feedback time-varying systems delayed input periodic system

Research on shell-side heat and mass transfer with multi-component in LNG spiral-wound heat exchanger under sloshing conditions

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Petroleum Science 2024年第2期21卷 1333-1345页

作者： Xue-Ping Du guang-Lei Yu Ya-Cheng Xu Zhi-j.e Chen Nai-Liang Li Huan-guang wang School of Low-carbon Energy and Power Engineering China University of Mining and TechnologyXuzhou221116JiangsuChina Key Laboratory of Thermo-Fluid Science and Engineering MOEXi'an Jiaotong UniversityXi'an710049ShaanxiChina Xi'an Aerospace Propulsion Test Technology Institute Xi'an710100ShaanxiChina

The spiral-wound heat exchanger(SWHE) is the primary low-temperature heat exchanger for large-scale LNG plants due to its high-pressure resistance, compact structure, and high heat exchange efficiency. This paper studied the shell-side heat and mass transfer characteristics of vapor-liquid two-phase mixed refrigerants in an SWHE by combining a multi-component model in FLUENT software with a customized multicomponent mass transfer model. Besides, the mathematical model under the sloshing condition was obtained through mathematical derivation, and the corresponding UDF code was loaded into FLUENT as the momentum source term. The results under the sloshing conditions were compared with the relevant parameters under the steady-state condition. The shell-side heat and mass transfer characteristics of the SWHE were investigated by adj.sting the component ratio and other working conditions. It was found that the sloshing conditions enhance the heat transfer performance and sometimes have insignificant effects. The sloshing condition is beneficial to reduce the flow resistance. The comprehensive performance of multi-component refrigerants has been improved and the improvement is more significant under sloshing conditions, considering both the heat transfer and pressure *** results will provide theoretical support for the research and design of multi-component heat and mass transfer enhancement of LNG SWHE under ocean sloshing conditions.

关键词： Spiral-wound heat exchanger Sloshing conditions Two-phase flow Multi-component Heat and mass transfer