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OPTIMAL SCHEME FOR SEQUENTIAL COMPUTATIONS OF F_m(z) INTEGRALS IN AB INITIO CALCULATIONS----COMBINATORY USE OF UPWARD AND DOWNWARD RECURSIONS
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《Chemical Research in Chinese Universities》 SCIE CAS 1986年第1期76-84,共9页
The quantitative rules of the transfer and variation of errors,when the Gaussian integral functions F.(z) are evaluated sequentially by recurring,have been expounded.The traditional viewpoint to negate the applicabili... The quantitative rules of the transfer and variation of errors,when the Gaussian integral functions F.(z) are evaluated sequentially by recurring,have been expounded.The traditional viewpoint to negate the applicability and reliability of upward recursive formula in principle is amended.An optimal scheme of upward-and downward-joint recursions has been developed for the sequential F(z) computations.No additional accuracy is needed with the fundamental term of recursion because the absolute error of Fn(z) always decreases with the recursive approach.The scheme can be employed in modifying any of existent subprograms for Fn<z> computations.In the case of p-d-f-and g-type Gaussians,combining this method with Schaad's formulas can reduce,at least,the additive operations by a factor 40%;the multiplicative and exponential operations by a factor 60%. 展开更多
关键词 combinatory USE OF UPWARD AND DOWNWARD RECURSIONS INTEGRALS IN AB INITIO CALCULATIONS OPTIMAL SCHEME FOR SEQUENTIAL COMPUTATIONS OF F_m down AB
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THE COMBINATORY METHOD FOR DETERMINATION OF THE TURBULENT FLUXES AND UNIVERSAL FUNCTIONS IN THE SURFACE LAYER 被引量:3
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作者 胡隐樵 奇跃进 《Acta meteorologica Sinica》 SCIE 1993年第1期101-109,共9页
A combinatory method of determining the turbulent fluxes in the surface layer has been developed and their general representations have been thus obtained.The universal functions of the (M-O) similarity in the surface... A combinatory method of determining the turbulent fluxes in the surface layer has been developed and their general representations have been thus obtained.The universal functions of the (M-O) similarity in the surface layer can be de- termined by the method.The results calculated by using the ITCE's data indicate that the method is feasible. 展开更多
关键词 combinatory method turbulent flux universal function surface layer
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COMBINATORY LOGIC AS THE FIRST-ORDER MATHEMATICAL THEORY
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作者 江明德 文蕙 《Chinese Science Bulletin》 SCIE EI CAS 1989年第24期2079-2083,共5页
I. INTRODUCTION The exploration for a unified basis of the combinatory logic and the predicate calculus will promote laying a strict and thorough mathematical foundation of the programming language possessing itself o... I. INTRODUCTION The exploration for a unified basis of the combinatory logic and the predicate calculus will promote laying a strict and thorough mathematical foundation of the programming language possessing itself of the functional and logic paradigms. The purpose of this note, proceeding from the algebraic oersoective, is to formulize the first-order mathematical 展开更多
关键词 combinatory LOGIC PREDICATE CALCULUS FIRST-ORDER mathemtical theory.
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Graph Guide Diffusion Solvers with Noises for Travelling Salesman Problem
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作者 Yan Kong Xinpeng Guo Chih-Hsien Hsia 《Computers, Materials & Continua》 2026年第3期689-707,共19页
With the development of technology,diffusion model-based solvers have shown significant promise in solving Combinatorial Optimization(CO)problems,particularly in tackling Non-deterministic Polynomial-time hard(NP-hard... With the development of technology,diffusion model-based solvers have shown significant promise in solving Combinatorial Optimization(CO)problems,particularly in tackling Non-deterministic Polynomial-time hard(NP-hard)problems such as the Traveling Salesman Problem(TSP).However,existing diffusion model-based solvers typically employ a fixed,uniform noise schedule(e.g.,linear or cosine annealing)across all training instances,failing to fully account for the unique characteristics of each problem instance.To address this challenge,we present GraphGuided Diffusion Solvers(GGDS),an enhanced method for improving graph-based diffusion models.GGDS leverages Graph Neural Networks(GNNs)to capture graph structural information embedded in node coordinates and adjacency matrices,dynamically adjusting the noise levels in the diffusion model.This study investigates the TSP by examining two distinct time-step noise generation strategies:cosine annealing and a Neural Network(NN)-based approach.We evaluate their performance across different problem scales,particularly after integrating graph structural information.Experimental results indicate that GGDS outperforms previous methods with average performance improvements of 18.7%,6.3%,and 88.7%on TSP-500,TSP-100,and TSP-50,respectively.Specifically,GGDS demonstrates superior performance on TSP-500 and TSP-50,while its performance on TSP-100 is either comparable to or slightly better than that of previous methods,depending on the chosen noise schedule and decoding strategy. 展开更多
关键词 Combinatorial optimization problem diffusion model noise schedule traveling salesman problem
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Non-Markovian dynamical solver for efficient combinatorial optimization
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作者 Haijie Xu Zhe Yuan 《Chinese Physics B》 2026年第2期583-590,共8页
We incorporate a non-Markovian feedback mechanism into the simulated bifurcation method for dynamical solvers addressing combinatorial optimization problems.By reinjecting a portion of dissipated kinetic energy into e... We incorporate a non-Markovian feedback mechanism into the simulated bifurcation method for dynamical solvers addressing combinatorial optimization problems.By reinjecting a portion of dissipated kinetic energy into each spin in a history-dependent and trajectory-informed manner,the method effectively suppresses early freezing induced by inelastic boundaries and enhances the system's ability to explore complex energy landscapes.Numerical results on the maximum cut(MAX-CUT)instances of fully connected Sherrington–Kirkpatrick(SK)spin glass models,including the 2000-spin K_(2000)benchmark,demonstrate that the non-Markovian algorithm significantly improves both solution quality and convergence speed.Tests on randomly generated SK instances with 100 to 1000 spins further indicate favorable scalability and substantial gains in computational efficiency.Moreover,the proposed scheme is well suited for massively parallel hardware implementations,such as field-programmable gate arrays,providing a practical and scalable approach for solving large-scale combinatorial optimization problems. 展开更多
关键词 non-Markovian dynamics simulated bifurcation combinatorial optimization maximum cut(MAX-CUT)problem spin glass
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Cooperative finite transmit-receive antenna selection and power allocation strategy for multi-target CFAR-detection in multisite MIMO radar intelligent group system under external uncertainty
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作者 Cheng QI Junwei XIE +6 位作者 Haowei ZHANG Bo WANG Jinlin ZHANG Weijian LIU Weike FENG Qun ZHANG Rennong YANG 《Chinese Journal of Aeronautics》 2026年第1期534-552,共19页
Within the domain of Intelligent Group Systems(IGSs),this paper develops a resourceaware multitarget Constant False Alarm Rate(CFAR)detection framework for multisite MIMO radar systems.It underscores the necessity of ... Within the domain of Intelligent Group Systems(IGSs),this paper develops a resourceaware multitarget Constant False Alarm Rate(CFAR)detection framework for multisite MIMO radar systems.It underscores the necessity of managing finite transmit and receive antennas and transmit power systematically to enhance detection performance.To tackle the multidimensional resource optimization challenge,we introduce a Cooperative Transmit-Receive Antenna Selection and Power Allocation(CTRSPA)strategy.It employs a perception-action cycle that incorporates uncertain external support information to optimize worst-case detection performance with multiple targets.First,we derive a closed-form expression that incorporates uncertainty for the noncoherent integration squared-law detection probability using the Neyman-Pearson criterion.Subsequently,a joint optimization model for antenna selection and power allocation in CFAR detection is formulated,incorporating practical radar resource constraints.Mathematically,this represents an NPhard problem involving coupled continuous and Boolean variables.We propose a three-stage method—Reformulation,Node Picker,and Convex Power Allocation—that capitalizes on the independent convexity of the optimization model for each variable,ensuring a near-optimal result.Simulations confirm the approach's effectiveness,efficiency,and timeliness,particularly for large-scale radar networks,and reveal the impact of threat levels,system layout,and detection parameters on resource allocation. 展开更多
关键词 Combinatorial optimization Constant False Alarm Rate(CFAR) Intelligent Group System Multisite MIMO radar Resource management Target detection
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Consistency and axiomatization of a natural extensional combinatory logic
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作者 蒋颖 《Science China Mathematics》 SCIE 1996年第9期897-908,共12页
In the light of a question of J. L. Krivine about the consistency of an extensional λ-theory,an extensional combinatory logic ECL+U(G)+RU_∞+ is established, with its consistency model provedtheoretically and it is s... In the light of a question of J. L. Krivine about the consistency of an extensional λ-theory,an extensional combinatory logic ECL+U(G)+RU_∞+ is established, with its consistency model provedtheoretically and it is shown the it is not equivalent to any system of universal axioms. It is expressed bythe theory in first order logic that, for every given group G of order n, there simultaneously exist infinitelymany universal retractions and a surjective n-tuple notion, such that each element of G acts as a permutationof the components of the n-tuple, and as an Ap-automorphism of the model; further each of the universalretractions is invarian under the action of the Ap-automorphisms induced by G The difference between thetheory and that of Krivine is the G need not be a symmetric group. 展开更多
关键词 λ-theory an exteaional combinatory logic consistency
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Optimization of Linear Sequence-controlled Copolymers for Maximizing Adsorption Capacity
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作者 Sheng-Da Zhao Qiu-Ju Chen +2 位作者 Zhi-Xin Liu Quan-Xiao Dong Xing-Hua Zhang 《Chinese Journal of Polymer Science》 2025年第10期1739-1748,共10页
The optimization of polymer structures aims to determine an optimal sequence or topology that achieves a given target property or structural performance.This inverse design problem involves searching within a vast com... The optimization of polymer structures aims to determine an optimal sequence or topology that achieves a given target property or structural performance.This inverse design problem involves searching within a vast combinatorial phase space defined by components,se-quences,and topologies,and is often computationally intractable due to its NP-hard nature.At the core of this challenge lies the need to evalu-ate complex correlations among structural variables,a classical problem in both statistical physics and combinatorial optimization.To address this,we adopt a mean-field approach that decouples direct variable-variable interactions into effective interactions between each variable and an auxiliary field.The simulated bifurcation(SB)algorithm is employed as a mean-field-based optimization framework.It constructs a Hamiltonian dynamical system by introducing generalized momentum fields,enabling efficient decoupling and dynamic evolution of strongly coupled struc-tural variables.Using the sequence optimization of a linear copolymer adsorbing on a solid surface as a case study,we demonstrate the applica-bility of the SB algorithm to high-dimensional,non-differentiable combinatorial optimization problems.Our results show that SB can efficiently discover polymer sequences with excellent adsorption performance within a reasonable computational time.Furthermore,it exhibits robust con-vergence and high parallel scalability across large design spaces.The approach developed in this work offers a new computational pathway for polymer structure optimization.It also lays a theoretical foundation for future extensions to topological design problems,such as optimizing the number and placement of side chains,as well as the co-optimization of sequence and topology. 展开更多
关键词 Combinatorial optimization Optimal design Sequence design COPOLYMER Adsorption problem
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New Series Involving Binomial Coefficients(Ⅲ)
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作者 SUN Zhi-wei 《Chinese Quarterly Journal of Mathematics》 2025年第4期372-392,共21页
We evaluate some series with summands involving a single binomial coefficient(^6k 3k).For example,we prove that■Motivated by Galois theory,we introduce the so-called Duality Principle for irrational series of Ramanu... We evaluate some series with summands involving a single binomial coefficient(^6k 3k).For example,we prove that■Motivated by Galois theory,we introduce the so-called Duality Principle for irrational series of Ramanujan’s type or Zeilberger’s type,and apply it to find 26 new irrational series identities.For example,we conjecture that■where ■for any integer d≡0,1 (mod 4) with (d/k) the Kronecker symbol. 展开更多
关键词 Binomial coefficient Combinatorial identity Infinite series Kronecker symbol L-FUNCTION
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Neural Codes Constructs Based on Combinatorial Design
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作者 Jin Huang 《Applied Mathematics》 2025年第1期42-60,共19页
Neuroscience (also known as neurobiology) is a science that studies the structure, function, development, pharmacology and pathology of the nervous system. In recent years, C. Cotardo has introduced coding theory into... Neuroscience (also known as neurobiology) is a science that studies the structure, function, development, pharmacology and pathology of the nervous system. In recent years, C. Cotardo has introduced coding theory into neuroscience, proposing the concept of combinatorial neural codes. And it was further studied in depth using algebraic methods by C. Curto. In this paper, we construct a class of combinatorial neural codes with special properties based on classical combinatorial structures such as orthogonal Latin rectangle, disjoint Steiner systems, groupable designs and transversal designs. These neural codes have significant weight distribution properties and large minimum distances, and are thus valuable for potential applications in information representation and neuroscience. This study provides new ideas for the construction method and property analysis of combinatorial neural codes, and enriches the study of algebraic coding theory. 展开更多
关键词 Combinatorial Neural Codes Orthogonal Latin Rectangle Steiner System Group Divisible Design Transversal Design
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Combinatorial innovation and lifecycle analysis of low-carbon energy technologies in China
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作者 Zerun Jin Shengjun Zhu 《Geography and Sustainability》 2025年第2期228-239,共12页
Measuring the lifecycle of low-carbon energy technologies is critical to better understanding the innovation pattern.However,previous studies on lifecycle either focus on technical details or just provide a general ov... Measuring the lifecycle of low-carbon energy technologies is critical to better understanding the innovation pattern.However,previous studies on lifecycle either focus on technical details or just provide a general overview,due to the lack of connection with innovation theories.This article attempts to fill this gap by analyzing the lifecycle from a combinatorial innovation perspective,based on patent data of ten low-carbon energy technologies in China from 1999 to 2018.The problem of estimating lifecycle stages can be transformed into analyzing the rise and fall of knowledge combinations.By building the international patent classification(IPC)co-occurrence matrix,this paper demonstrates the lifecycle evolution of technologies and develops an efficient quantitative index to define lifecycle stages.The mathematical measurement can effectively reflect the evolutionary pattern of technologies.Additionally,this article relates the macro evolution of lifecycle to the micro dynamic mechanism of technology paradigms.The sign of technology maturity is that new inventions tend to follow the patterns established by prior ones.Following this logic,this paper identifies different trends of paradigms in each technology field and analyze their transition.Furthermore,catching-up literature shows that drastic transformation of technology paradigms may open“windows of opportunity”for laggard regions.From the results of this paper,it is clear to see that latecomers can catch up with pioneers especially when there is a radical change in paradigms.Therefore,it is important for policy makers to capture such opportunities during the technology lifecycle and coordinate regional innovation resources. 展开更多
关键词 Combinatorial innovation Technology lifecycle Low-carbon energy technologies CATCHING-UP
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Advancements in production planning and scheduling within steel manufacturing:A review and its intelligent development
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作者 Yongzhou Wang Zhong Zheng +4 位作者 Liang Guo Yongjie Yang Shiyu Zhang Xueying Liu Xiaoqiang Gao 《International Journal of Minerals,Metallurgy and Materials》 2025年第10期2322-2340,共19页
In the context of reducing its carbon emissions,the Chinese steel industry is currently undergoing an intelligent transformation to enhance its profitability and sustainability.The optimization of production planning ... In the context of reducing its carbon emissions,the Chinese steel industry is currently undergoing an intelligent transformation to enhance its profitability and sustainability.The optimization of production planning and scheduling plays a pivotal role in realizing these objectives such as improving production efficiency,saving energy,reducing carbon emissions,and enhancing quality.However,current practices in steel enterprises are largely dependent on experience-driven manual decision approaches supported by information systems,which are inadequate to meet the complex requirements of the industry.This study explores the current situation in production planning and scheduling,analyzes the characteristics and limitations of existing methods,and emphasizes the necessity and trends of intelligent systems.It surveys the current literature on production planning and scheduling in steel enterprises and analyzes the theoretical advancements and practical challenges associated with combinatorial and sequential optimization in this field.A key focus is on the limitations of current models and algorithms in effectively addressing the multi-objective and multiconstraint characteristics of steel produc-tion.To overcome these challenges,a novel framework for intelligent production planning and scheduling is proposed.This framework leverages data-and knowledge-driven decision-making and scenario adaptability,enabling the system to respond dynamically to real-time production conditions and market fluctuations.By integrating artificial intelligence and advanced optimization methodologies,the proposed framework improves the efficiency,cost-effectiveness,and environmental sustainability of steel manufacturing. 展开更多
关键词 steel manufacturing production planning and scheduling intelligent decision-making data-and knowledge-driven scene ad-aptability combinatorial and sequential optimization
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A Genetic Algorithm-Based Double Auction Framework for Secure and Scalable Resource Allocation in Cloud-Integrated Intrusion Detection Systems
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作者 Siraj Un Muneer Ihsan Ullah +1 位作者 Zeshan Iqbal Rajermani Thinakaran 《Computers, Materials & Continua》 2025年第12期4959-4975,共17页
The complexity of cloud environments challenges secure resource management,especially for intrusion detection systems(IDS).Existing strategies struggle to balance efficiency,cost fairness,and threat resilience.This pa... The complexity of cloud environments challenges secure resource management,especially for intrusion detection systems(IDS).Existing strategies struggle to balance efficiency,cost fairness,and threat resilience.This paper proposes an innovative approach to managing cloud resources through the integration of a genetic algorithm(GA)with a“double auction”method.This approach seeks to enhance security and efficiency by aligning buyers and sellers within an intelligent market framework.It guarantees equitable pricing while utilizing resources efficiently and optimizing advantages for all stakeholders.The GA functions as an intelligent search mechanism that identifies optimal combinations of bids from users and suppliers,addressing issues arising from the intricacies of cloud systems.Analyses proved that our method surpasses previous strategies,particularly in terms of price accuracy,speed,and the capacity to manage large-scale activities,critical factors for real-time cybersecurity systems,such as IDS.Our research integrates artificial intelligence-inspired evolutionary algorithms with market-driven methods to develop intelligent resource management systems that are secure,scalable,and adaptable to evolving risks,such as process innovation. 展开更多
关键词 Cloud computing combinatorial double auction genetic algorithm optimization resource allocation intrusion detection system(IDS) cloud security
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Combinatorial optimization with dual meanfield dynamics
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作者 Wen-Biao Xu Zi-Song Shen +1 位作者 Ying Tang Pan Zhang 《Communications in Theoretical Physics》 2025年第12期178-186,共9页
Combinatorial optimization problems and ground state problems of spin glasses are crucial in various fields of science and technology.However,they often belong to the computational class of NP-hard,presenting signific... Combinatorial optimization problems and ground state problems of spin glasses are crucial in various fields of science and technology.However,they often belong to the computational class of NP-hard,presenting significant computational challenges.Traditional algorithms inspired by statistical physics like simulated annealing have been widely adopted.Recently,advancements in Ising machines,such as quantum annealers and coherent Ising machines,offer new paradigms for solving these problems efficiently by embedding them into the analog evolution of nonlinear dynamical systems.However,existing dynamics-based algorithms often suffer from low convergence rates and local minima traps.In this work,we introduce the dual mean-field dynamics into Ising machines.The approach integrates the gradient force and the transverse force into the dynamics of Ising machines in solving combinatorial optimization problems,making it easier for the system to jump out of the local minimums and allowing the dynamics to explore wider in configuration space.We conduct extensive numerical experiments using the Sherrington–Kirkpatrick spin glass up to 10000 spins and the maximum cut problems with the standard G-set benchmarks.The numerical results demonstrate that our dual mean-field dynamics approach enhances the performance of base Ising machines,providing a more effective solution for large-scale combinatorial optimization problems. 展开更多
关键词 combinatorial optimization Ising machines mean field dynamics
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An Adaptive Hybrid Metaheuristic for Solving the Vehicle Routing Problem with Time Windows under Uncertainty
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作者 Manuel J.C.S.Reis 《Computers, Materials & Continua》 2025年第11期3023-3039,共17页
The Vehicle Routing Problem with Time Windows(VRPTW)presents a significant challenge in combinatorial optimization,especially under real-world uncertainties such as variable travel times,service durations,and dynamic ... The Vehicle Routing Problem with Time Windows(VRPTW)presents a significant challenge in combinatorial optimization,especially under real-world uncertainties such as variable travel times,service durations,and dynamic customer demands.These uncertainties make traditional deterministic models inadequate,often leading to suboptimal or infeasible solutions.To address these challenges,this work proposes an adaptive hybrid metaheuristic that integrates Genetic Algorithms(GA)with Local Search(LS),while incorporating stochastic uncertainty modeling through probabilistic travel times.The proposed algorithm dynamically adjusts parameters—such as mutation rate and local search probability—based on real-time search performance.This adaptivity enhances the algorithm’s ability to balance exploration and exploitation during the optimization process.Travel time uncertainties are modeled using Gaussian noise,and solution robustness is evaluated through scenario-based simulations.We test our method on a set of benchmark problems from Solomon’s instance suite,comparing its performance under deterministic and stochastic conditions.Results show that the proposed hybrid approach achieves up to a 9%reduction in expected total travel time and a 40% reduction in time window violations compared to baseline methods,including classical GA and non-adaptive hybrids.Additionally,the algorithm demonstrates strong robustness,with lower solution variance across uncertainty scenarios,and converges faster than competing approaches.These findings highlight the method’s suitability for practical logistics applications such as last-mile delivery and real-time transportation planning,where uncertainty and service-level constraints are critical.The flexibility and effectiveness of the proposed framework make it a promising candidate for deployment in dynamic,uncertainty-aware supply chain environments. 展开更多
关键词 Vehicle routing problem with time windows(VRPTW) hybrid metaheuristic genetic algorithm local search uncertainty modeling stochastic optimization adaptive algorithms combinatorial optimization transportation and logistics robust scheduling
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Progressive quantum algorithm for maximum independent set with quantum alternating operator ansatz
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作者 Xiao-Hui Ni Ling-Xiao Li +3 位作者 Yan-Qi Song Zheng-Ping Jin Su-Juan Qin Fei Gao 《Chinese Physics B》 2025年第7期75-87,共13页
The quantum alternating operator ansatz algorithm(QAOA+)is widely used for constrained combinatorial optimization problems(CCOPs)due to its ability to construct feasible solution spaces.In this paper,we propose a prog... The quantum alternating operator ansatz algorithm(QAOA+)is widely used for constrained combinatorial optimization problems(CCOPs)due to its ability to construct feasible solution spaces.In this paper,we propose a progressive quantum algorithm(PQA)to reduce qubit requirements for QAOA+in solving the maximum independent set(MIS)problem.PQA iteratively constructs a subgraph likely to include the MIS solution of the original graph and solves the problem on it to approximate the global solution.Specifically,PQA starts with a small-scale subgraph and progressively expands its graph size utilizing heuristic expansion strategies.After each expansion,PQA solves the MIS problem on the newly generated subgraph using QAOA+.In each run,PQA repeats the expansion and solving process until a predefined stopping condition is reached.Simulation results show that PQA achieves an approximation ratio of 0.95 using only 5.57%(2.17%)of the qubits and 17.59%(6.43%)of the runtime compared with directly solving the original problem with QAOA+on Erd?s-Rényi(3-regular)graphs,highlighting the efficiency and scalability of PQA. 展开更多
关键词 quantum alternating operator ansatz algorithm(QAOA+) constrained combinatorial optimization problems(CCOPs) maximum independent set(MIS) feasible space
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Construction and Evaluation of Merged Pharmacophore Based on Peroxisome Proliferator Receptor-Alpha Agonists 被引量:3
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作者 乔连生 贺昱甦 +5 位作者 霍晓乾 蒋芦荻 陈艳昆 陈茜 张燕玲 李贡宇 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第4期508-516,I0002,共10页
Pharmacophore is a commonly used method for molecular simulation, including ligand-based pharmacophore (LBP) and structure-based pharmacophore (SBP). LBP can be utilized to identify active compounds usual with low... Pharmacophore is a commonly used method for molecular simulation, including ligand-based pharmacophore (LBP) and structure-based pharmacophore (SBP). LBP can be utilized to identify active compounds usual with lower accuracy, and SBP is able to use for distin- guishing active compounds from inactive compounds with frequently higher missing rates. Merged pharmacophore (MP) is presented to integrate advantages and avoid shortcomings of LBP and SBP. In this work, LBP and SBP models were constructed for the study of per- oxisome proliferator receptor-alpha (PPARα) agonists. According to the comparison of the two types of pharmacophore models, mainly and secondarily pharmacological features were identified. The weight and tolerance values of these pharmacological features were adjusted to construct MP models by single-factor explorations and orthogonal experimental design based on SBP model. Then, the reliability and screening efficiency of the best MP model were validated by three databases. The best MP model was utilized to compute PPARα activity of compounds from traditional Chinese medicine. The screening efficiency of MP model outperformed individual LBP or SBP model for PPARα agonists, and was similar to combinatorial screening of LBP and SBP. However, MP model might have an advantage over the combination of LBP and SBP in evaluating the activity of compounds and avoiding the inconsistent prediction of LBP and SBP, which would be beneficial to guide drug design and optimization. 展开更多
关键词 Merged pharmacophore Ligand-based pharmacophore Structure-based pharmaeophore Peroxisome proliferator receptor-alpha DOCKING Combinatorial screening
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Estrogen Receptor α and β Expressions in Hypothalamus-pituitary-ovary Axis in Rats Exposed Lactationally to Soy Isoflavones and Bisphenol A 被引量:5
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作者 BO YU QING-FENG CHEN +7 位作者 ZHAO-PING LIU HE-FEI XU XIAO-PENG ZHANG QAIN XIANG WEN-ZHONG ZHANG WEN-MING CUI XIN ZHANG NING LI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2010年第5期357-362,共6页
Objectives This paper aims to investigate the uterotrophic activities of lactational exposure to combination of soy isoflavones (SIF) and bisphenol A (BPA) and to examine estrogen receptor α (ERα) and estrogen... Objectives This paper aims to investigate the uterotrophic activities of lactational exposure to combination of soy isoflavones (SIF) and bisphenol A (BPA) and to examine estrogen receptor α (ERα) and estrogen receptor β (ERβ) expressions in hypothalamus-pituitary-ovary axis and uterus.Methods Maternal rats that were breeding about 8 litters were randomly divided into four groups with seven dams in each group.Dams in different treatment groups received corn oil (control),150 mg/kg BW of SIF,150 mg/kg BW of BPA or combination of 150 mg/kg BW of SIF and 150 mg/kg BW of BPA,respectively,from postnatal day 5 to 11 (PND5-11) by gavage.On PND12 and PND70,10 female litters were killed and hypothalamus,pituitary,ovary and uterus were collected.ERα and ERβ expressions in these organs were detected with Western blotting assay.And vaginal opening time and estrus cycle were examined in animals fed for PND70.Results On PND12,the relative uterine weight of rats treated with ISF or BPA or their combination was significantly higher than that of untreated rats (P〈0.05).But the relative uterine weight of rats in the co-exposure group was slightly lower than that in the group only exposed to SIF or BPA.On PND 70,however,the relative uterine weight in each treatment group was not statistically different from that in the control group (P〈0.05).Vaginal opening time and estrus cycle in groups treated with SIF or BPA or their combination were similar to those in the control group (P〈0.05).Exposure to SIF or BPA or their combination could up-regulate or down-regulate ERα and ERβ expressions in hypothalamus,pituitary,ovary and uterus on PND12 and PND70.These regulation patterns for ERα and ERβ were different in different organs at different time points.Conclusion Lactational exposure to ISF or BPA or their combination could induce uterotrophic responses in neonate rats,which disappeared in later life.But these data fail to suggest a possibility for synergic actions between SIF and BPA.It was also demonstrated that the uterotrophic effects of SIF and BPA exposure might,at least,involve modification of ERα or ERβ expressions in the hypothalamus-pituitary-ovary axis. 展开更多
关键词 Soy isoflavones Bisphenol A combinatory actions Estrogen receptors
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固相有机合成中钯催化的交叉偶联反应研究进展 被引量:1
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作者 郝树林 张政朴 刘长令 《高分子通报》 CAS CSCD 北大核心 2011年第7期1-23,共23页
过渡金属钯催化交叉偶联反应是形成碳—碳键的一种十分有效的方法,因此钯催化的C—C偶联反应引起了更多人们的广泛关注,并发展了多种不同的C—C偶联反应,包括Heck反应、Negishi反应、Suzuki偶联和Stille偶联等。固相有机合成具有反应条... 过渡金属钯催化交叉偶联反应是形成碳—碳键的一种十分有效的方法,因此钯催化的C—C偶联反应引起了更多人们的广泛关注,并发展了多种不同的C—C偶联反应,包括Heck反应、Negishi反应、Suzuki偶联和Stille偶联等。固相有机合成具有反应条件温和、可使多种活性官能团兼容、受空间位阻影响小、具有高度的化学选择性、毒性小、副产物少且易于分离纯化、产率高等优点,近几年来一直是催化化学和固相合成与组合化学的研究热点。本文根据不同的分类标准结合本课题组的研究工作综述了近年来人们对Heck反应、Negishi反应、Suzuki偶联和Stille偶联在固相有机合成中钯催化交叉偶联反应的研究进展,最后展望了固相合成中钯催化交叉偶联反应的研究前景。 展开更多
关键词 钯催化 偶联反应 HECK反应 Negishi反应 SUZUKI偶联 Stille偶联 固相合成与组合化学
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BER Performance of Soft Decision Modulations Based on PCSS System 被引量:2
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作者 Ming-Duo Liu Li-Li Guo Hong-Lei Li 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第2期22-26,共5页
Recently,soft decision modulations become the highlight of parallel combinatory spread spectrum ( PCSS) system. Existing soft decision BPSK and APK modulations are given and compared in the thesis. In order to apply s... Recently,soft decision modulations become the highlight of parallel combinatory spread spectrum ( PCSS) system. Existing soft decision BPSK and APK modulations are given and compared in the thesis. In order to apply soft decision QPSK modulation based on PCSS system,the correlation of superposition PN sequences is discussed. A weighted summation algorithm is adopted in QPSK demodulation to recover the whole orthogonal correlation of the superposition sequences; meanwhile the bit error rate of weighting soft decision QPSK modulation is simulated. The simulation results show that the bit error rate performance of proposed soft decision QPSK modulation based on PCSS system is better than that of hard decision modulation. The method proposed can be widely adopted in engineering application. 展开更多
关键词 parallel combinatory SPREAD spectrum SYSTEM soft decision MODULATIONS correlation of SUPERPOSITION PN SEQUENCES
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