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Laguerre Isoparametric Hypersurfaces in R^n with Two Distinct Non-zero Principal Curvatures

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Acta Mathematica Sinica,English Series 2014年第1期30卷 169-180页

作者： Yu ping song School of Mathematical Sciences Xiamen University

An umbilical free oriented hypersurfacex：M→Rnwith non-zero principal curvatures is called a Laguerre isoparametric hypersurface if its Laguerre form C=i Ciωi=iρ1（Ei（logρ）（r ri）Ei（r））ωi vanishes and Laguerre shape operator S=ρ1（S 1 rid）has constant ***ρ=i（r ri）2,r=r1＋r2＋···＋rn 1n 1is the mean curvature radius andSis the shape operator ofx.{Ei}is a local basis for Laguerre metric g=ρ2III with dual basis{ωi}and III is the third fundamental form *** this paper,we classify all Laguerre isoparametric hypersurfaces in Rn（n〉3）with two distinct non-zero principal curvatures up to Laguerre transformations.

关键词： Laguerre geometry isoparametric hypersurfaces non-zero principal curvatures

Electrochemical adsorption and passivation on gold surface in alkaline thiourea solutions

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Rare Metals 2020年第8期39卷 951-958页

作者： Wen-Juan Li He Zhou An-ping Bai yong-Sheng song Liu-Lu Cai Shui-Lin Zheng Qi-Dong Zhang song Cao School of Chemical and Environmental Engineering China University of Mining and Technology(Beijing)Beijing 100083China GRIMAT Engineering Institute Co. Ltd.(GRIMAT)Beijing 101407China National Engineering Laboratory of Biohydrometallurgy GRINM Resources and Environment Tech.Co.LtdBeijing 101407China Beijing Vocational College of Labour and Social Security Beijing 102200China

An electrochemical method was used to examine Au surface absorption and passivation under the most commonly employed pH conditions in an alkaline Au leaching *** polarization at different pH values was obtained through the current step *** pH 10,no absorption layer was *** the pH was increased to 11,an absorption layer was formed through the Au electrode *** pH 12,the entire system could not be stabilized,even after long durations because of the thiourea oxidation and *** samples were analyzed by scanning electron microscopy(SEM),energy-dispersive X-ray spectroscopy(EDS),and atomic force microscopy(AFM).AFM observations of the Au plating surface and SEM-EDS analyses for the Au-coated graphite surface indicated that a passivation membrane was formed on the Au surface after its use in the alkaline thiourea Au leaching ***-step leaching was used to confirm the conclusions drawn from the experimental *** twostage experimental results further confirmed the existence of a passivation membrane.

关键词： Alkaline thiourea Gold Electrochemical adsorption Passivation

An efficient quantum proactive incremental learning algorithm

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 49-57页

作者： Lingxiao Li Jing Li Yanqi song Sujuan Qin Qiaoyan Wen Fei Gao State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications School of Cyberspace Security Beijing University of Posts and Telecommunications

In scenarios where a large amount of data needs to be learned, incremental learning can make full use of old knowledge, significantly reduce the computational cost of the overall learning process, and maintain high performance. In this paper, taking the MaxCut problem as our example, we introduce the idea of incremental learning into quantum computing, and propose a Quantum Proactive Incremental Learning algorithm(QPIL). Instead of a one-off training of quantum circuit, QPIL contains a multi-phase training on gradually-increased subgraphs of all vertices, proactively reducing large-scale problems to smaller ones to solve in steps, providing an efficient solution for MaxCut. Specifically, some vertices and corresponding edges are randomly selected for training to obtain optimized parameters of the quantum circuit at first. Then, in each incremental phase, the remaining vertices and corresponding edges are gradually added and the parameters obtained from the previous phase are reused in the parameter initialization of the current phase. We perform experiments on 120 different small-scale graphs, and it shows that QPIL performs superior to prevalent quantum and classical baselines in terms of approximation ratio(AR), time cost, anti-forgetting, and solving stability. In particular, QPIL's AR surpasses 20% of mainstream quantum baselines, and the time cost is less than 1/5 of them. The idea of QPIL is expected to inspire efficient and high-quality solutions in large-scale Max Cut and other combinatorial optimization problems.

关键词： variational quantum algorithm incremental learning multi-phase training MaxCut quantum computing

Amino acid assisted aqueous synthesis of highly stable CsPbBr_(3)nanocrystals for cell imaging

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Nano Research 2025年第1期18卷 675-683页

作者： Xue Li Yanan Guo Guoying Tan Qingyi Liu Nan song Yu Tang State Key Laboratory of Applied Organic Chemistry Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu ProvinceCollege of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou 014030China

Lead halide perovskite nanocrystals(NCs)exhibit excellent optoelectronic performance and have drawn great interests in the fields of biological imaging and ***,the poor stability of CsPbX_(3)(X=Cl,Br,I)in water is still a challenge to hinder their practical *** this work,a facile strategy has been developed for aqueous synthesis of CsPbX_(3) nanocrystals,in which L-glutamic acid(LGlu)has been used to replace oleic acid in the synthetic *** from the synergic effects of L-Glu and oleylamine(OAm),CsPbBr_(3)nanocrystals(L-Glu/OAm-CsPbBr_(3)NCs)with high water stability have been directly prepared under a mild condition at room temperature in water,facilitated by the process of crystal phase transformation from Cs_(4)PbBr_(6) to CsPbBr_(3).L-Glu/OAm-CsPbBr_(3)NCs exhibit a high quantum yield of 85%and a narrow full width at half maximum of 16 nm,demonstrating their efficient luminescence in ***,L-Glu on the surface have contributed greatly to an acidic environment and passivation of surface defects,improving the water stability and dispersibility of CsPbBr_(3)***,L-Glu/OAm-CsPbBr_(3)NCs exhibit great biocompatibility due to the presence of L-Glu,resulting in their good performance for HeLa cell ***,we propose a facile and effective method to prepare CsPbBr_(3)nanocrystals with excellent water stability by using L-Glu and OAm as cooperated ligands and expand their application in cell imaging.

关键词： aqueous synthesis cell imaging lead halide perovskite nanocrystals L-glutamic acid phase transformation

Adaptive finite-time backstepping control for attitude tracking of spacecraft based on rotation matrix

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Chinese Journal of Aeronautics 2014年第2期27卷 375-382页

作者： Guo yong song Shenmin Center for Control Theory and Guidance Technology Harbin Institute of Technology

This paper investigates two finite-time controllers for attitude control of spacecraft based on rotation matrix by an adaptive backstepping method. Rotation matrix can overcome the draw- backs of unwinding which makes a spacecraft perform a large-angle maneuver when a small-angle maneuver in the opposite rotational direction is sufficient to achieve the objective, With the use of adaptive control, the first robust finite-time controller is continuous without a chattering phenom- enon. The second robust finite-time controller can compensate external disturbances with unknown bounds. Theoretical analysis shows that both controllers can make a spacecraft following a time-varying reference attitude signal in finite time and guarantee the stability of the overall closed-loop system. Numerical simulations are presented to demonstrate the effectiveness of the proposed control schemes.

关键词： Adaptive control Attitude control Backstepping Finite-time control Robustness

Data Gathering in Wireless Sensor Networks Via Regular Low Density Parity Check Matrix

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IEEE/CAA Journal of Automatica Sinica 2018年第1期5卷 83-91页

作者： Xiaoxia song yong Li Department of Computer Science ShanxiDatong University

A great challenge faced by wireless sensor networks(WSNs) is to reduce energy consumption of sensor nodes. Fortunately, the data gathering via random sensing can save energy of sensor nodes. Nevertheless, its randomness and density usually result in difficult implementations, high computation complexity and large storage spaces in practical settings. So the deterministic sparse sensing matrices are desired in some situations. However,it is difficult to guarantee the performance of deterministic sensing matrix by the acknowledged metrics. In this paper, we construct a class of deterministic sparse sensing matrices with statistical versions of restricted isometry property(St RIP) via regular low density parity check(RLDPC) matrices. The key idea of our construction is to achieve small mutual coherence of the matrices by confining the column weights of RLDPC matrices such that St RIP is satisfied. Besides, we prove that the constructed sensing matrices have the same scale of measurement numbers as the dense measurements. We also propose a data gathering method based on RLDPC matrix. Experimental results verify that the constructed sensing matrices have better reconstruction performance, compared to the Gaussian, Bernoulli, and CSLDPC matrices. And we also verify that the data gathering via RLDPC matrix can reduce energy consumption of WSNs.

关键词： Data gathering regular low density parity check(RLDPC) matrix sensing matrix signal reconstruction wireless sensor networks(WSNs)

Blackboard Mechanism Based Ant Colony Theory for Dynamic Deployment of Mobile Sensor Networks

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Journal of Bionic Engineering 2008年第3期5卷 197-203页

作者： Guang-ping Qi ping song Ke-jie Li School of Aerospace Science and Engineering Beij＇ing Institute of Technology Beo＇ing 100081 P. R. China

A novel bionic swarm intelligence algorithm, called ant colony algorithm based on a blackboard mechanism, is proposed to solve the autonomy and dynamic deployment of mobiles sensor networks effectively. A blackboard mechanism is introduced into the system for making pheromone and completing the algorithm. Every node, which can be looked as an ant, makes one information zone in its memory for communicating with other nodes and leaves pheromone, which is created by ant itself in naalre. Then ant colony theory is used to find the optimization scheme for path planning and deployment of mobile Wireless Sensor Network （WSN）. We test the algorithm in a dynamic and unconfigurable environment. The results indicate that the algorithm can reduce the power consumption by 13% averagely, enhance the efficiency of path planning and deployment of mobile WSN by 15% averagely.

关键词： ant colony algorithm wireless sensor network blackboard mechanism bionic swarm intelligence algorithm

Optimizing multi-parameter distributed fiber sensors:a hybrid Rayleigh-Brillouin-Raman System approach

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Light(Science & Applications) 2024年第3期13卷 393-395页

作者： Kwang yong song Dept.of Physics Chung-Ang University84 Heukseok-roDongjak-guSeoul 06974Korea

An optimized single-end hybrid Rayleigh,Brillouin,and Raman distributed fiber sensing system has been developed for simultaneous measurement of multiple *** system integrates 3-bit pulse coding for the Raman signal and the Brillouin amplification of the Rayleigh-backscattered signal,discriminating strain,temperature,and vibration using a single sensing fiber.

关键词： fiber Rayleigh signal

Shu-Gan-Liang-Xue Decoction Simultaneously Down-regulates Expressions of Aromatase and Steroid Sulfatase in Estrogen Receptor Positive Breast Cancer Cells

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Chinese Journal of Cancer Research 2011年第3期23卷 208-213页

作者： Xue-song Fu ping-ping Li Key Laboratory of Carcinogenesis and Translational Research （Ministry of Education） Department of Integrated Traditional Chinese and Western MedicinePeking University School of OncologyBeijing Cancer Hospital ＆ InstituteBeijing 100142China

Objective：Estradiol （E2） plays an important role in the development of breast *** postmenopausal women,the estrogen can be synthesized via aromatase （CYP19） pathway and steroid-sulfatase （STS） pathway in peripheral tissues,when the production in ovary has *** objective of our study was to explore the effects of Shu-Gan-Liang-Xue Decoction （SGLXD） on the expressions of CYP19 and STS in estrogen receptor positive breast cancer MCF-7 and T47D ***：The effects of SGLXD on the cell viability of MCF-7 and T47D were analyzed by MTT *** quantitative real-time RT-PCR and Western blot,we evaluated the mRNA and protein expressions of CYP19 and STS in MCF-7 and T47D cells after SGLXD ***：By MTT assay,the cell viability rates of MCF-7 and T47D were significantly inhibited by SGLXD in a dose-dependent manner,the IC50 values were 40.07 mg/ml for MCF-7 cells and 25.62 mg/ml for T47D cells,*** evidenced by real-time PCR and Western blot,the high concentrations of SGLXD significantly down-regulated the expressions of CYP19 and STS both in the transcript level and the protein ***：The results suggest that SGLXD is a potential dual aromatase-sulfatase inhibitor by simultaneously down-regulating the expressions of CYP19 and STS in MCF-7 and T47D cells.

关键词： Shu-Gan-Liang-Xue Decoction (SGLXD) Aromatase (CYP19) Steroid-sulfatase (STS) Breast cancer