检索结果-南通市图书馆

PREDICTION OF STAGE-DISCHARGE IN RIVER USING KALMAN FILTER

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 1991年第1期3卷 51-55页

作者： Fan, yu-chen Water Conservancy and Hydropower Research Inst Beijing China

In this paper Mannig's resistance coefficient n is used as a state-variable for Kalman filter, the stage h in the river as an observation-variable. Comparing this form of Kalman filter with Simons' form, the result of... 详细信息

关键词： Computers Applications Flow of Water Hydrodynamics Mathematical Models Mathematical Techniques Differential Equations

Quantum Algorithm for Boolean Equation Solving and Quantum Algebraic Attack on Cryptosystems

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2022年第1期35卷 373-412页

作者： chen yu-Ao GAO Xiao-Shan Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

This paper presents a quantum algorithm to decide whether a Boolean equation system F has a solution and to compute one if F does have solutions with any given success *** runtime complexity of the algorithm is polynomial in the size of F and the condition number of certain Macaulay matrix associated with *** a consequence,the authors give a polynomial-time quantum algorithm for solving Boolean equation systems if their condition numbers are polynomial in the size of *** authors apply the proposed quantum algorithm to the cryptanalysis of several important cryptosystems:The stream cipher Trivum,the block cipher AES,the hash function SHA-3/Keccak,the multivariate public key cryptosystems,and show that they are secure under quantum algebraic attack only if the corresponding condition numbers are *** leads to a new criterion for designing such cryptosystems which are safe against the attack of quantum computers:The corresponding condition number.

关键词： Block cipher AES Boolean equation solving condition number hash function SHA3/Keccak HHL algorithm MPKC polynomial system solving quantum algorithm stream cipher Trivum

Biomimetic nanomedicine toward personalized disease theranostics

在线全文

学校读者我要写书评

暂无评论

Nano Research 2021年第8期14卷 2491-2511页

作者： Huisong Hao yu chen Meiying Wu School of Pharmaceutical Sciences(Shenzhen) Sun Yat-sen UniversityShenzhen 518107China School of Life Sciences Shanghai UniversityShanghai 200444China

Despite nanoparticle-based drug delivery systems have aroused broad research interest in the biomedical fields,the rising challenges such as easy recognition by the immune system and low accumulation in diseased sites significantly hinder their further clinical *** wrapped in cell membrane have emerged as a distinctive strategy to overcome these limitations due to the superior marriage of natural cell membrane and artificial nanomaterials,which endow them with prominent advantages in disease diagnosis and treatment,such as targeted drug transport,prolonged drug half-life,and diminished immunogenicity and *** this review,we mainly highlight and discuss the evolving progresses and advantages of cell membrane-based biomimetic nanosystems in the detection and treatment of various diseases over the past five years,including oncology,bacterial infections,brain diseases,and inflammatory diseases,which would benefit researchers in better and comprehensively understanding the complicated microenvironment of diseases and developing personalized biomimetic nanomedicines for different *** current challenges and potential opportunities for the future clinical translation of cell membrane coating nanotechnology are also covered.

关键词： diseases theranostics personalized nanomedicine biomimetic

On the behavior of the product of independent random variables

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Mathematics 2006年第3期49卷 342-359页

作者： SU Chun chen yu Department of Statistics and Finance University of Science and Technology of China Hefei 230026 China Department of Statistics and Finance University of Science and Technology of China Hefei 230026 China

For two independent non-negative random variables X and Y, we treat X as the initial variable of major importance and Y as a modifier (such as the interest rate of a portfolio).Stability in the tail behaviors of the product compared with that of the original variable X is of practical interests. In this paper, we study the tail behaviors of the product XY when the distribution of X belongs to the classes L and S, respectively. Under appropriate conditions, we show that the distribution of the product XY is in the same class as X when X belongs to class L or S, in other words, classes L and S are stable under some mild conditions on the distribution of Y. We also show that if the distribution of X is in class L(γ) (γ＞ 0) and continuous, then the product XY is in L if and only if Y is unbounded.

关键词： independent product, stability, tails of a distribution, heavy-tailed.

Time-frequency analysis of internal waves generated by a towed and self-propelled submerged body model

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2023年第6期35卷 1191-1207页

作者： yu-hang Li Fei-yu chen Li-ping Qin Ke chen yun-xiang You Zhengzhou Electromechanical Engineering Research Institute Zhengzhou450015China Henan Key Laboratory of Underwater Intelligence Equipment Zhengzhou450015China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai200240China Yazhou Bay Institute of Deepsea Technology Shanghai Jiao Tong UniversityShanghai200240China

The spectrogram,based on a short-time Fourier transform,can visualize the time-dependent frequency spectrum of waves and is easy to *** time-frequency analysis method provides crucial information about waves generated by moving vessels and has been utilized to analyze Kelvin ship waves and internal *** further study the internal waves induced by a submerged body,an experiment is conducted for the towed and self-propelled SUBOFF model in a stratified *** internal wave elevation signals are captured using electronic conductivity *** with the calculation results of theoretical model,the high-frequency component of internal waves is *** high-frequency component has the exact same characteristics in both the towed and self-propelled model experiment and is consistent with the theoretical results for all Froude ***,this component is composed mainly of lee *** spectral characteristics identification,a low-frequency component is discovered in the spectrogram in addition to the lee wave *** intensity of the low-frequency component is tightly related to the vortex structure behind the submerged *** vortex structure depends on the net momentum imparted by the submerged ***,this component is composed mainly of wake waves induced by the vortex structure.

关键词： Stratified fluid internal waves submerged body experimental study time-frequency analysis

Technological advances expand our knowledge of lysosomal dysfunction in neurodegeneration

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2023年第3期18卷 539-540页

作者： Chase chen yu chen Ellen Sidransky Medical Genetics Branch National Institutes of HealthNational Human Genome Research InstituteNational Institutes of HealthBethesdaMDUSA

In the almost seven decades since the initial discovery of the lysosome as an organelle,our understanding of the role of lysosomes has greatly *** now know lysosomal function encompasses far more than its traditionally described role as the cell’s“garbage disposal”,referring to its well-established catabolic *** are integral to maintaining cellular health and viability,and they act as a major signaling hub within the cell(Ballabio and Bonifacino,2020).

关键词： function. function traditionally

Generic Existence of Infinitely Many Non-contractible Closed Geodesics on Compact Space Forms

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第7期40卷 1674-1684页

作者： Hui Liu yu chen Wang School of Mathematics and Statistics Wuhan UniversityWuhan430072P.R.China School of Mathematics Tianjin Normal UniversityTianjin300384P.R.China

Let M=S^(n)/Γand h be a nontrivial element of finite order p inπ_(1)(Μ),where the integers n,p≥2,Γis a finite abelian group which acts freely and isometrically on the n-sphere and therefore M is diffeomorphic to a compact space *** this paper,we prove that there are infinitely many non-contractible closed geodesics of class[h]on the compact space form with C^(r)-generic Finsler metrics,where 4≤r≤∞.The conclusion also holds for Cr-generic Riemannian metrics for 2≤r≤∞.The proof is based on the resonance identity of non-contractible closed geodesics on compact space forms.

关键词： Compact space forms non-contractible closed geodesics generic Finsler metrics resonance identity

A regeneratable dynamic differential evolution algorithm for neural networks with integer weights

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第12期11卷 939-947页

作者： Jian BAO yu chen Jin-shou yu School of lnformation Science and Engineering East China Universi~ of Science and Technology Shanghai 200237 China Institute of Sofrtware and Intelligent Technology Hangzhou Dianzi University Hangzhou 310018 China

Neural networks with integer weights are more suited for embedded systems and hardware implementations than those with real weights. However, many learning algorithms, which have been proposed for training neural networks with float weights, are inefficient and difficult to train for neural networks with integer weights. In this paper, a novel regeneratable dynamic differential evolution algorithm (RDDE) is presented. This algorithm is efficient for training networks with integer weights. In comparison with the conventional differential evolution algorithm (DE), RDDE has introduced three new strategies: (1) A regeneratable strategy is introduced to ensure further evolution, when all the individuals are the same after several iterations such that they cannot evolve further. In other words, there is an escape from the local minima. (2) A dynamic strategy is designed to speed up convergence and simplify the algorithm by updating its population dynamically. (3) A local greedy strategy is introduced to improve local searching ability when the population approaches the global optimal solution. In comparison with other gradient based algorithms, RDDE does not need the gradient information, which has been the main obstacle for training networks with integer weights. The experiment results show that RDDE can train integer-weight networks more efficiently.

关键词： Differential evolution Integer weights Neural networks Greedy Embedded systems Function approximation

Interplay of surface geometry and vorticity dynamics in incompressible flows on curved surfaces

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2017年第9期38卷 1191-1212页

作者： Qian SHI yu chen Xilin XIE Department of Aeronautics and Astronautics Fudan UniversityShanghai 200433China

Incompressible viscous flows on curved surfaces are considered with respect to the interplay of surface geometry, curvature, and vorticity dynamics. Free flows and cylindrical wakes over a Gaussian bump are numerically solved using a surface vorticity- stream function formulation. Numerical simulations show that the Gaussian curvature can generate vorticity, and non-uniformity of the Gaussian curvature is the main cause. In the cylindrical wake, the bump dominated by the positive Gaussian curvature can significantly affect the vortex street by forming velocity depression and changing vorticity transport. The results may provide possibilities for manipulating surface flows through local change in the surface geometry.

关键词： two-dimensional flow vorticity dynamics incompressible viscous curvature