期刊文献+
共找到962篇文章
< 1 2 49 >
每页显示 20 50 100
A Robust Direct-Discretized RNN for Time-Dependent Optimization Constrained by Nonlinear Equalities and Its Applications
1
作者 Guangfeng Cheng Binbin Qiu +1 位作者 Jinjin Guo Yu Han 《IEEE/CAA Journal of Automatica Sinica》 2025年第9期1866-1877,共12页
In recent years,numerous recurrent neural network(RNN)models have been reported for solving time-dependent nonlinear optimization problems.However,few existing RNN models simultaneously involve nonlinear equality cons... In recent years,numerous recurrent neural network(RNN)models have been reported for solving time-dependent nonlinear optimization problems.However,few existing RNN models simultaneously involve nonlinear equality constraints,direct discretization,and noise suppression.This limitation presents challenges when existing models are applied to practical engineering problems.Additionally,most current discrete-time RNN models are derived from continuous-time models,which may not perform well for solving essentially discrete problems.To handle these issues,a robust direct-discretized RNN(RDD-RNN)model is proposed to efficiently realize time-dependent optimization constrained by nonlinear equalities(TDOCNE)in the presence of various time-dependent noises.Theoretical analyses are provided to reveal that the proposed RDD-RNN model possesses excellent convergence and noise-suppressing capability.Furthermore,numerical experiments and manipulator control instances are conducted and analyzed to validate the superior robustness of the proposed RDD-RNN model under various time-dependent noises,particularly quadratic polynomial noise.Eventually,small target detection experiments further demonstrate the practicality of the RDD-RNN model in image processing applications. 展开更多
关键词 Manipulator control quadratic polynomial noise robust direct-discretized recurrent neural network(RDD-RNN) small target detection time-dependent optimization constrained by nonlinear equalities(TDOCNE)
在线阅读 下载PDF
Emerging of Stochastic Dynamical Equalities and Steady State Thermodynamics from Darwinian Dynamics 被引量:10
2
作者 P.Ao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第5期1073-1090,共18页
The evolutionary dynamics first conceived by Darwin and Wallace, referring to as Darwinian dynamics in the present paper, has been found to be universally valid in biology. The statistical mechanics and thermodynamics... The evolutionary dynamics first conceived by Darwin and Wallace, referring to as Darwinian dynamics in the present paper, has been found to be universally valid in biology. The statistical mechanics and thermodynamics, while enormous successful in physics, have been in an awkward situation of wanting a consistent dynamical understanding. Here we present from a formal point of view an exploration of the connection between thermodynamics and Darwinian dynamics and a few related topics. We first show that the stochasticity in Darwinian dynamics implies the existence temperature, hence the canonical distribution of Boltzmann-Gibbs type. In term of relative entropy the Second Law of thermodynamics is dynamically demonstrated without detailed balance condition, and is valid regardless of size of the system. In particular, the dynamical component responsible for breaking detailed balance condition does not contribute to the change of the relative entropy. Two types of stochastic dynamical equalities of current interest are explicitly discussed in the present approach: One is based on Feynman-Kac formula and another is a generalization of Einstein relation. Both are directly accessible to experimental tests. Our demonstration indicates that Darwinian dynamics represents logically a simple and straightforward starting point for statistical mechanics and thermodynamics and is complementary to and consistent with conservative dynamics that dominates the physical sciences. Present exploration suggests the existence of a unified stochastic dynamical framework both near and far from equilibrium. 展开更多
关键词 non-equilibrium processes Darwinian dynamics generalized Einstein relation absence of detailed balance stochastic dynamical equalities
在线阅读 下载PDF
Smoothing Newton-Like Method for the Solution of Nonlinear Systems of Equalities and Inequalities 被引量:2
3
作者 Liu Yang Yanping Chen Xiaojiao Tong 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2009年第2期224-236,共13页
In this paper,we present a smoothing Newton-like method for solving nonlinear systems of equalities and inequalities.By using the so-called max function,we transfer the inequalities into a system of semismooth equalit... In this paper,we present a smoothing Newton-like method for solving nonlinear systems of equalities and inequalities.By using the so-called max function,we transfer the inequalities into a system of semismooth equalities.Then a smoothing Newton-like method is proposed for solving the reformulated system,which only needs to solve one system of linear equations and to perform one line search at each iteration. The global and local quadratic convergence are studied under appropriate assumptions. Numerical examples show that the new approach is effective. 展开更多
关键词 Nonlinear systems of equalities and inequalities semismooth function smoothingNewton method global convergence local quadratic convergence.
在线阅读 下载PDF
CHEBYSHEV APPROXIMATION BY FUNCTIONS HAVING RESTRICTED RANGES WITH EQUALITIES
4
作者 李冲 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1993年第1期57-66,共10页
In this paper, we establish a new type of alternation theory for more general restricted ranges Chebyshev approximation with equalities. The uniqueness and strong uniqueness theorems are given. Applying the results, w... In this paper, we establish a new type of alternation theory for more general restricted ranges Chebyshev approximation with equalities. The uniqueness and strong uniqueness theorems are given. Applying the results, we obtain the alternation theorem and uniqueness theorem for best coposilive approximation. 展开更多
关键词 Chebyshev APPROXIMATION generaized HAAR subspace RESTRICTED RANGES APPROXIMATION with equalities ALTERNATION strong uniqueness COPOSITIVE approximation.
在线阅读 下载PDF
PROBLEM OF EQUALITIES IN EIGENVALUE INEQUALITIES FOR PRODUCTS OF POSITIVE SEMIDEFINITE HERMITIAN MATRICES
5
作者 Xi Boyan(Inner Mongolia Teachers College for Nationalities,Tongliao 028043,PRC) 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2000年第S1期95-97,共3页
Let A∈C<sup>m×n</sup>,set eigenvalues of matrix A with |λ<sub>1</sub> (A)|≥|λ<sub>2</sub>(A)|≥…≥|λ<sub>n</sub>(A)|,write A≥0 if A is a positive semid... Let A∈C<sup>m×n</sup>,set eigenvalues of matrix A with |λ<sub>1</sub> (A)|≥|λ<sub>2</sub>(A)|≥…≥|λ<sub>n</sub>(A)|,write A≥0 if A is a positive semidefinite Hermitian matrix, and denote∧<sub>k</sub> (A)=diag (λ<sub>1</sub>(A),…,λ<sub>k</sub>(A)),∧<sub>(</sub>(n-k).(A)=diag (λ<sub>k+1</sub>(A),…,λ<sub>n</sub>(A))for any k=1, 2,...,n if A≥0. Denote all n order unitary matrices by U<sup>n×n</sup>.Problem of equalities to hold in eigenvalue inequalities for products of matrices 展开更多
关键词 AB In WANG PROBLEM OF equalities IN EIGENVALUE INequalities FOR PRODUCTS OF POSITIVE SEMIDEFINITE HERMITIAN MATRICES
在线阅读 下载PDF
Relating Optimization Problems to Systems of Inequalities and Equalities
6
作者 H. W. Corley E. O. Dwobeng 《American Journal of Operations Research》 2020年第6期284-298,共15页
In quantitative decision analysis, an analyst applies mathematical models to make decisions. Frequently these models involve an optimization problem to determine the values of the decision variables, a system </spa... In quantitative decision analysis, an analyst applies mathematical models to make decisions. Frequently these models involve an optimization problem to determine the values of the decision variables, a system </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> of possibly non</span></span><span style="font-family:Verdana;">- </span><span style="font-family:Verdana;">li</span><span style="font-family:Verdana;">near inequalities and equalities to restrict these variables, or both. In this</span><span style="font-family:""><span style="font-family:Verdana;"> note, </span><span style="font-family:Verdana;">we relate a general nonlinear programming problem to such a system </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> in</span><span style="font-family:Verdana;"> such </span><span style="font-family:Verdana;">a way as to provide a solution of either by solving the other—with certain l</span><span style="font-family:Verdana;">imitations. We first start with </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> and generalize phase 1 of the two-phase simplex method to either solve </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> or establish that a solution does not exist. A conclusion is reached by trying to solve </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> by minimizing a sum of artificial variables subject to the system </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> as constraints. Using examples, we illustrate </span><span style="font-family:Verdana;">how this approach can give the core of a cooperative game and an equili</span><span style="font-family:Verdana;">brium for a noncooperative game, as well as solve both linear and nonlinear goal programming problems. Similarly, we start with a general nonlinear programming problem and present an algorithm to solve it as a series of systems </span><i><span style="font-family:Verdana;">S</span></i><span style="font-family:Verdana;"> by generalizing the </span></span><span style="font-family:Verdana;">“</span><span style="font-family:Verdana;">sliding objective</span><span style="font-family:Verdana;"> function </span><span style="font-family:Verdana;">method</span><span style="font-family:Verdana;">”</span><span style="font-family:Verdana;"> for</span><span style="font-family:Verdana;"> two-dimensional linear programming. An example is presented to illustrate the geometrical nature of this approach. 展开更多
关键词 OPTIMIZATION Inequalities and equalities Goal Programming GAMES Diophantine Equations
在线阅读 下载PDF
Nonequilibrium work equalities in isolated quantum systems 被引量:1
7
作者 柳飞 欧阳钟灿 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期53-60,共8页
We briefly introduce the quantum Jarzynski and Bochkov-Kuzovlev equalities .in isolated quantum Hamiltonian sys- tems, including their origin, their derivations using a quantum Feynman-Kac formula, the quantum Crooks ... We briefly introduce the quantum Jarzynski and Bochkov-Kuzovlev equalities .in isolated quantum Hamiltonian sys- tems, including their origin, their derivations using a quantum Feynman-Kac formula, the quantum Crooks equality, the evolution equations governing the characteristic functions of the probability density functions for the quantum work, and recent experimental verifications. Some resultsare given here for the first time. We particularly emphasize the formally structural consistence between these quantum equalities and their classical counterparts, which are useful for understanding the existing equalities and pursuing new fluctuation relations in other complex quantum systems. 展开更多
关键词 nonequilibrium isolated quantum systems work equality probability density function of quantumwork quantum Feynman-Kac formula
原文传递
Rank Equalities for Anti-involutory Matrices
8
作者 WANG Shi-heng 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第2期311-316,共6页
Some rank equalities are established for anti-involutory matrices. In particular, we get the formulas for the rank of the difference, the sum and the commutator of anti-involutory matrices.
关键词 rank equality idempotent matrix involutory matrix anti-involutory matrix partitioned matrix generalized inverse COMMUTATOR
在线阅读 下载PDF
Numerical Radius Inequalities for Sums and Products of Operators
9
作者 Wasim Audeh 《Advances in Linear Algebra & Matrix Theory》 2019年第3期35-42,共8页
A numerical radius inequality due to Shebrawi and Albadawi says that: If Ai, Bi, Xi are bounded operators in Hilbert space, i = 1,2,..., n , and f,g be nonnegative continuous functions on [0, ∞) satisfying the relati... A numerical radius inequality due to Shebrawi and Albadawi says that: If Ai, Bi, Xi are bounded operators in Hilbert space, i = 1,2,..., n , and f,g be nonnegative continuous functions on [0, ∞) satisfying the relation f(t)g(t) = t (t∈[0, ∞)), then for all r≥1. We give sharper numerical radius inequality which states that: If Ai, Bi, Xi are bounded operators in Hilbert space, i = 1,2,..., n , and f,g be nonnegative continuous functions on [0, ∞) satisfying the relation f(t)g(t) = t (t∈[0, ∞)), then ?where . Moreover, we give many numerical radius inequalities which are sharper than related inequalities proved recently, and several applications are given. 展开更多
关键词 Numeriacl RADIUS OPERATOR Norm OPERATOR Matrix INEQUALITY EQUALITY Offdiagonal Part
在线阅读 下载PDF
A Nonmonotone Smoothing Newton Method for Systems of Nonlinear Equalities and Inequalities Based on a New Smoothing Function
10
作者 Liu-yang YUAN Fei CUI +1 位作者 Zhong-ping WAN Zi-yue WANG 《Acta Mathematicae Applicatae Sinica》 2026年第2期392-403,共12页
In this paper,a nonmonotone smoothing Newton method is proposed for solving systems of nonlinear equalities and inequalities.By constructing a new smoothing function,the problem is approximated via a family of paramet... In this paper,a nonmonotone smoothing Newton method is proposed for solving systems of nonlinear equalities and inequalities.By constructing a new smoothing function,the problem is approximated via a family of parameterized smooth equations.A smoothing Newton method is developed for solving the systems of nonlinear equalities and inequalities by adopting a modified nonmontone line search technique.And the global and local superlinear convergence of the algorithm are proved under mild assumptions.The preliminary numerical results are reported. 展开更多
关键词 systems of nonlinear equalities and inequalities smoothing newton method nonmonotone line search global convergence local superlinear convergence
原文传递
Weighted variation inequalities for differential operators and singular integrals in higher dimensions 被引量:9
11
作者 MA Tao TORREA Jose L. XU QuanHua 《Science China Mathematics》 SCIE CSCD 2017年第8期1419-1442,共24页
We prove weighted q-variation inequalities with 2<q<∞for sharp truncations of singular integral operators in higher dimensions.The vector-valued extensions of these inequalities are also given.Parallel results ... We prove weighted q-variation inequalities with 2<q<∞for sharp truncations of singular integral operators in higher dimensions.The vector-valued extensions of these inequalities are also given.Parallel results are proven for differential operators. 展开更多
关键词 variation inequalities A_(p) weights differential operators singular integrals vector-valued variationin equalities
原文传递
Low-Cycle Fatigue Behavior of Ultrafine-Grained Pure Titanium
12
作者 Liu Xiaoyan Wang Zixuan +2 位作者 Yang Xirong Luo Lei Wang Jingzhong 《稀有金属材料与工程》 北大核心 2026年第5期1191-1198,共8页
Ultrafine-grained(UFG)pure titanium was produced by equal channel angular pressing for 4 passes,followed by rotatory swaging at room temperature.The strain-controlled low-cycle fatigue tests of UFG and coarse-grained(... Ultrafine-grained(UFG)pure titanium was produced by equal channel angular pressing for 4 passes,followed by rotatory swaging at room temperature.The strain-controlled low-cycle fatigue tests of UFG and coarse-grained(CG)pure titanium were conducted by Instron electro-hydraulic servo fatigue testing machine in the strain amplitude range of 0.5%—1.1%at room temperature.Transmission electron microscope(TEM)and scanning electron microscope were used to investigate the microstructure and fracture surface of UFG pure titanium after fatigue tests.Results show that UFG pure titanium exhibits a longer low-cycle fatigue life,compared with the CG pure titanium.For example,at a total strain amplitude of 0.5%,UFG and CG pure titanium has fatigue life of 10850 and 4820 cycles,respectively.Significant cyclic softening occurs in UFG pure titanium,except in the case of a total strain amplitude of 0.5%.Hysteresis loop area is increased rapidly with the increase in strain amplitude.The fracture surface shows that the fatigue crack is initiated from the specimen surface.A series of fatigue striations and many microcracks exist in the propagation region.With the increase in strain amplitude,the predominant failure mode is transformed from ductile failure into quasi-cleavage failure.Dislocation slip is the main plastic deformation mechanism of UFG pure titanium during low-cycle fatigue deformation. 展开更多
关键词 ultrafine-grained pure titanium equal channel angular pressing+rotatory swaging low-cycle fatigue dislocation slip
原文传递
THE EQUALITIES OF THE CHERN CLASSES
13
作者 石赫 《Systems Science and Mathematical Sciences》 SCIE EI CSCD 1989年第1期4-13,共10页
In this paper we generalize the results of [1]and prove that,for any given 4≤k≤n,theChern classes of hypersurface V_n corresponding to the partitions of k also satisfy some equalities.Furthermore,we obtain the equal... In this paper we generalize the results of [1]and prove that,for any given 4≤k≤n,theChern classes of hypersurface V_n corresponding to the partitions of k also satisfy some equalities.Furthermore,we obtain the equalities of Chern classes concretely for k=4,5,6. 展开更多
关键词 CHERN CLASSES HYPERSURFACE PARTITIONS equalities
在线阅读 下载PDF
On the Case of Equalities in Comparison Results for Elliptic Equations Related to Gauss Measure
14
作者 Yu Juan TIAN Feng Quan LI 《Journal of Mathematical Research and Exposition》 CSCD 2010年第5期761-774,共14页
In this paper, we deal with a Dirichlet problem for linear elliptic equations related to Gauss measure. For this problem, we study the converse of some inequalities proved by other authors, in the sense that we study ... In this paper, we deal with a Dirichlet problem for linear elliptic equations related to Gauss measure. For this problem, we study the converse of some inequalities proved by other authors, in the sense that we study the case of equalities and show that equalities are achieved only in the "symmetrized" situations. In addition, under other assumptions, we give a different form of comparison results and discuss the corresponding case of equalities. 展开更多
关键词 comparison results equalities REARRANGEMENTS Gauss measure elliptic equation.
在线阅读 下载PDF
IoT-Assisted Cloud Data Sharing with Revocation and Equality Test under Identity-Based Proxy Re-Encryption
15
作者 Han-Yu Lin Tung-Tso Tsai Yi-Chuan Wang 《Computers, Materials & Continua》 2026年第3期431-447,共17页
Cloud services,favored by many enterprises due to their high flexibility and easy operation,are widely used for data storage and processing.However,the high latency,together with transmission overheads of the cloud ar... Cloud services,favored by many enterprises due to their high flexibility and easy operation,are widely used for data storage and processing.However,the high latency,together with transmission overheads of the cloud architecture,makes it difficult to quickly respond to the demands of IoT applications and local computation.To make up for these deficiencies in the cloud,fog computing has emerged as a critical role in the IoT applications.It decentralizes the computing power to various lower nodes close to data sources,so as to achieve the goal of low latency and distributed processing.With the data being frequently exchanged and shared between multiple nodes,it becomes a challenge to authorize data securely and efficiently while protecting user privacy.To address this challenge,proxy re-encryption(PRE)schemes provide a feasible way allowing an intermediary proxy node to re-encrypt ciphertext designated for different authorized data requesters without compromising any plaintext information.Since the proxy is viewed as a semi-trusted party,it should be taken to prevent malicious behaviors and reduce the risk of data leakage when implementing PRE schemes.This paper proposes a new fog-assisted identity-based PRE scheme supporting anonymous key generation,equality test,and user revocation to fulfill various IoT application requirements.Specifically,in a traditional identity-based public key architecture,the key escrow problem and the necessity of a secure channel are major security concerns.We utilize an anonymous key generation technique to solve these problems.The equality test functionality further enables a cloud server to inspect whether two candidate trapdoors contain an identical keyword.In particular,the proposed scheme realizes fine-grained user-level authorization while maintaining strong key confidentiality.To revoke an invalid user identity,we add a revocation list to the system flows to restrict access privileges without increasing additional computation cost.To ensure security,it is shown that our system meets the security notion of IND-PrID-CCA and OW-ID-CCA under the Decisional Bilinear Diffie-Hellman(DBDH)assumption. 展开更多
关键词 Equality test proxy re-encryption IDENTITY-BASED REVOCABLE fog computing
在线阅读 下载PDF
Low-Complexity OTFS Channel Equalization Based on CLU-MMSE
16
作者 Jia Haoxiang Zhao Danfeng +1 位作者 Xin Yu Hua Jian 《ZTE Communications》 2026年第1期16-24,共9页
In view of the high computational complexity of traditional linear equalization algorithms in Orthogonal Time Frequency Space(OTFS)systems,a minimum mean square error(MMSE)channel equalization algorithm based on Matri... In view of the high computational complexity of traditional linear equalization algorithms in Orthogonal Time Frequency Space(OTFS)systems,a minimum mean square error(MMSE)channel equalization algorithm based on Matrix Chunking Lower and Upper Triangular Decomposition(CLU)is proposed.The proposed algorithm derives the structural properties of the chunked MMSE equalization matrix by leveraging the block diagonal structure of the Cyclic Prefix OTFS(CP-OTFS)time-domain channel matrix and the quasi-band structure of its constituent block matrices.On this basis,triangular decomposition combined with forward and backward substitution is used to avoid matrix inversion.This approach significantly reduces the complexity of the MMSE algorithm without sacrificing its performance. 展开更多
关键词 OTFS equalization algorithm MMSE Lower and Upper Triangular Decomposition
在线阅读 下载PDF
A Comprehensive Review and Algorithmic Analysis of Histogram-Based Contrast Enhancement Techniques for Medical Imaging
17
作者 Saira Ali Bhatti Maqbool Khan +4 位作者 Arshad Ahmad Muhammad Shahid Anwar Leila Jamel Aisha M.Mashraqi Wadee Alhalabi 《Computer Modeling in Engineering & Sciences》 2026年第3期37-79,共43页
Medical imaging is essential in modern health care,allowing accurate diagnosis and effective treatment planning.These images,however,often demonstrate low contrast,noise,and brightness distortion that reduce their dia... Medical imaging is essential in modern health care,allowing accurate diagnosis and effective treatment planning.These images,however,often demonstrate low contrast,noise,and brightness distortion that reduce their diagnostic reliability.This review presents a structured and comprehensive analysis of advanced histogram equalization(HE)-based techniques for medical image enhancement.Our review methodology encompasses:(1)classical HE approaches and related limitations in medical domains;(2)adaptive schemes like Adaptive Histogram Equalization(AHE)and Contrast Limited Adaptive Histogrma Equalization(CLAHE)and their advance variants;(3)brightnesspreserving schemes like BBHE and MMBEBHE and related algorithms;(4)dynamic and recursive histogram equalization methods incorporating DHE and RMSHE;(5)fuzzy logic-based enhancement methodologies addressing uncertainty and noise in medical images;and(6)hybrid optimization methodologies through the application of metaheuristic algorithms(World Cup Optimization,Particle Swarm Optimization,Genetic Algorithms,along with histogram-based methodologies.)There is also a comparative discussion given based on contrast improvement,image brightness preservation,noise management,and computational efficiency.Such advancements have better capabilities of improving image quality,which is more important for improved diagnosis and image analysis. 展开更多
关键词 Medical imaging image enhancement techniques histogram equalization contrast enhancement noise reduction brightness preservation diagnostic accuracy
在线阅读 下载PDF
Lithology identification using borehole images by contrast-limited adaptive histogram equalization and machine learning models
18
作者 Enming Li Pablo Segarra +4 位作者 JoséA.Sanchidrián Zahir Ahmed Ignacio Catalán Alberto Fernández Santiago Gómez 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第3期1698-1718,共21页
Agile lithology identification can assist mining by providing important information in the exploration and production of mineral resources.This study proposes a new lithology recognition procedure using video-logging ... Agile lithology identification can assist mining by providing important information in the exploration and production of mineral resources.This study proposes a new lithology recognition procedure using video-logging of boreholes with an endoscope,applied to six production blocks in a limestone quarry.Images are automatically extracted from the videos and the lithology is classified into three classes based on clay content,i.e.massive limestone,brecciated limestone,and high amount of clay.The image quality is evaluated with a gray pixel intensity threshold and three no-reference image quality metrics,i.e.perception-based image quality evaluator,natural image quality evaluator,and blind/referenceless image spatial quality evaluator.After removing low-quality images,7583 images are retained and used for developing lithology classification models using six optimized classification techniques.The contrast-limited adaptive histogram equalization(CLAHE)technique is used to improve image quality.Ten color characteristics involving three percentiles of red,green and blue pixel intensities,together with color counting and five texture characteristics-correlation,entropy,homogeneity,contrast and energy-are used as inputs.Bayesian optimized light gradient boosting machine model performs best,with an overall accuracy of 88.04%,and a precision on the classes of massive limestone,brecciated limestone and high amount of clay of 90.72%,83.52%and 85.29%,respectively,for the testing set.The feature importance scores show that the color counting is the most significant parameter for the development of the classification model.Compared with previous image-based methodologies,this study provides a more flexible and cheaper procedure to identify lithology. 展开更多
关键词 Lithology identification Borehole images ENDOSCOPE Light gradient boosting machine Contrast-limited adaptive histogram equalization(CLAHE)
在线阅读 下载PDF
THOUGHTS FOR A NEW ERA
19
《ChinAfrica》 2026年第4期6-6,共1页
Women’s rights and gender equality,as essential pillars of social progress and human development,have become a shared pursuit of the international community.Chinese President Xi Jinping on 13 October 2025 delivered a... Women’s rights and gender equality,as essential pillars of social progress and human development,have become a shared pursuit of the international community.Chinese President Xi Jinping on 13 October 2025 delivered a keynote address at the opening ceremony of the Global Leaders’Meeting on Women in Beijing. 展开更多
关键词 gender equality human development social progress international community global leaders meeting keynote address Chinese President Xi Jinping womens rights
原文传递
Complexity-Reduced Equalization for 200 Gbit/s PON Downstream Systems Based on SSB Modulation and Direct Detection
20
作者 Yang Tao Huang Xingang +3 位作者 Ma Zhuang Zhong Yiming Huang Xiatao Liu Bo 《ZTE Communications》 2026年第1期56-64,共9页
The 200 Gbit/s passive optical network(PON)is most likely to be the next-generation scheme following 50G PON.The costeffective direct detection(DD)system is the economical choice.However,larger-capacity DD systems wil... The 200 Gbit/s passive optical network(PON)is most likely to be the next-generation scheme following 50G PON.The costeffective direct detection(DD)system is the economical choice.However,larger-capacity DD systems will face much more serious power fading caused by chromatic dispersion(CD)combined with square-law DD and thereby significantly increases the complexity of equalization algorithms.In this paper,a 200 Gbit/s Nyquist 4-level pulse amplitude modulation(PAM4)single side-band(SSB)modulation-DD downlink scheme is designed,and a low complexity quadratic-nonlinear equalizer is proposed for this system.The computational complexity of the quadratic nonlinear equalizer is about 28%of that of the conventional Volterra nonlinear equalizer,while still exhibiting excellent nonlinear equalization ability.Simulation results for the 200 Gbit/s system with 20 km fiber transmission show that it can achieve a power budget of 29 dB,while a 30.4 dB power budget is obtained in the 50 Gbit/s experimental transmission. 展开更多
关键词 200 Gbit/s passive optical network single side band modulation direct detection EQUALIZATION
在线阅读 下载PDF
上一页 1 2 49 下一页 到第
使用帮助 返回顶部