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Study of algorithms of new slender ship theory of wave resistance 被引量:2
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作者 Duan-feng Han Yun-Bo Li and De-bo Huang 《Journal of Marine Science and Application》 2003年第2期53-60,共8页
In this paper, Noblesse's New Slender-Ship Wave-Making Theory was investigated numerically. Detailed expressions of zeroth and lst order wave resistance have been derived and calculation programs have also been co... In this paper, Noblesse's New Slender-Ship Wave-Making Theory was investigated numerically. Detailed expressions of zeroth and lst order wave resistance have been derived and calculation programs have also been compiled. In the single and double integral terms of Green function, the kernel function of wave resistance expression, special function expansion method and Chebyshev polynomials approach have been adopted respectively, which greatly simplify the calculation and increase the convergence speed. 展开更多
关键词 new slender-ship wave resistance theory wave resistance Green function POTENTIAL algorithm
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QUANTUM COLLISION SEARCH ALGORITHM AGAINST NEW FORK-256 被引量:1
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作者 Du Fangwei Wang Hong Ma Zhi 《Journal of Electronics(China)》 2014年第4期366-370,共5页
In order to improve the attack efficiency of the New FORK-256 function, an algorithm based on Grover's quantum search algorithm and birthday attack is proposed. In this algorithm, finding a collision for arbitrary... In order to improve the attack efficiency of the New FORK-256 function, an algorithm based on Grover's quantum search algorithm and birthday attack is proposed. In this algorithm, finding a collision for arbitrary hash function only needs O(2m/3) expected evaluations, where m is the size of hash space value. It is proved that the algorithm can obviously improve the attack efficiency for only needing O(2 74.7) expected evaluations, and this is more efficient than any known classical algorithm, and the consumed space of the algorithm equals the evaluation. 展开更多
关键词 Quantum computation Quantum collision Grover's search algorithm new FORK-256CLC number:TN918.1
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Identification of High-Risk Scenarios for Cascading Failures in New Energy Power Grids Based on Deep Embedding Clustering Algorithms
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作者 Xueting Cheng Ziqi Zhang +1 位作者 Yueshuang Bao Huiping Zheng 《Energy Engineering》 EI 2023年第11期2517-2529,共13页
At present,the proportion of new energy in the power grid is increasing,and the random fluctuations in power output increase the risk of cascading failures in the power grid.In this paper,we propose a method for ident... At present,the proportion of new energy in the power grid is increasing,and the random fluctuations in power output increase the risk of cascading failures in the power grid.In this paper,we propose a method for identifying high-risk scenarios of interlocking faults in new energy power grids based on a deep embedding clustering(DEC)algorithm and apply it in a risk assessment of cascading failures in different operating scenarios for new energy power grids.First,considering the real-time operation status and system structure of new energy power grids,the scenario cascading failure risk indicator is established.Based on this indicator,the risk of cascading failure is calculated for the scenario set,the scenarios are clustered based on the DEC algorithm,and the scenarios with the highest indicators are selected as the significant risk scenario set.The results of simulations with an example power grid show that our method can effectively identify scenarios with a high risk of cascading failures from a large number of scenarios. 展开更多
关键词 new energy power system deep embedding clustering algorithms cascading failures
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Parameters of new three-water model based on nuclear magnetic experiment and optimization algorithm
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作者 KANG Nan HONG Xin +3 位作者 ZHANG Lihua PAN Baozhi TANG Lei ZHANG Pengji 《Global Geology》 2023年第1期57-62,共6页
Clastic rock reservoir is the main reservoir type in the oil and gas field.Archie formula or various conductive models developed on the basis of Archie’s formula are usually used to interpret this kind of reservoir,a... Clastic rock reservoir is the main reservoir type in the oil and gas field.Archie formula or various conductive models developed on the basis of Archie’s formula are usually used to interpret this kind of reservoir,and the three-water model is widely used as well.However,there are many parameters in the threewater model,and some of them are difficult to determine.Most of the determination methods are based on the statistics of large amount of experimental data.In this study,the authors determine the value of the parameters of the new three-water model based on the nuclear magnetic data and the genetic optimization algorithm.The relative error between the resistivity calculated based on these parameters and the resistivity measured experimentally at 100%water content is 0.9024.The method studied in this paper can be easily applied without much experimental data.It can provide reference for other regions to determine the parameters of the new three-water model. 展开更多
关键词 new three-water model optimization algorithm NMR water saturation rock electric parameters
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Highly Accurate Golden Section Search Algorithms and Fictitious Time Integration Method for Solving Nonlinear Eigenvalue Problems
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作者 Chein-Shan Liu Jian-Hung Shen +1 位作者 Chung-Lun Kuo Yung-Wei Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1317-1335,共19页
This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue problems.For each eigen-parameter the vector variable is solve... This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue problems.For each eigen-parameter the vector variable is solved from a nonhomogeneous linear system obtained by reducing the number of eigen-equation one less,where one of the nonzero components of the eigenvector is normalized to the unit and moves the column containing that component to the right-hand side as a nonzero input vector.1D and 2D golden section search algorithms are employed to minimize the merit functions to locate real and complex eigenvalues.Simultaneously,the real and complex eigenvectors can be computed very accurately.A simpler approach to the nonlinear eigenvalue problems is proposed,which implements a normalization condition for the uniqueness of the eigenvector into the eigenequation directly.The real eigenvalues can be computed by the fictitious time integration method(FTIM),which saves computational costs compared to the one-dimensional golden section search algorithm(1D GSSA).The simpler method is also combined with the Newton iterationmethod,which is convergent very fast.All the proposed methods are easily programmed to compute the eigenvalue and eigenvector with high accuracy and efficiency. 展开更多
关键词 Nonlinear eigenvalue problem quadratic eigenvalue problem two new merit functions golden section search algorithm fictitious time integration method
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A NEW EFFICIENT 3D OSTEOTOMY ALGORITHM FOR COMPUTER OPERATION SIMULATION
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作者 Jing Li Guiping Jiang +1 位作者 Shuxiang Li Bin Yang(Dept. Of BME. The First Military Medical University)(Dept. Of Oral and Maxillofacial Surgery’ Sun Yat-sen University of Medical SciencesGuangZhou, Guangdong China 510515.) 《Chinese Journal of Biomedical Engineering(English Edition)》 1999年第3期43-43,共1页
关键词 OPENGL A new EFFICIENT 3D OSTEOTOMY algorithm FOR COMPUTER OPERATION SIMULATION
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Database Encoding and A New Algorithm for Association Rules Mining
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作者 Tong Wang Pilian He 《通讯和计算机(中英文版)》 2006年第3期77-81,共5页
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Apriori算法及其改进算法Apriori-new的应用分析
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作者 彭敢 《现代计算机》 2012年第22期3-5,12,共4页
对Apriori算法进行应用分析,针对其不足之处,提出一种新的改进型算法——Aprior-new,给出该算法的工作过程,并对该算法进行应用分析。将两种算法进行应用对比,结果表明,Apriori-new算法占用内存少,执行效率更高。
关键词 APRIORI算法 Apriori-new 应用分析 应用对比
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New pattern recognition system in the e-nose for Chinese spirit identification 被引量:4
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作者 曾慧 李强 谷宇 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第2期164-169,共6页
This paper presents a new pattern recognition system for Chinese spirit identification by using the polymer quartz piezoelectric crystal sensor based e-nose. The sensors are designed based on quartz crystal microbala... This paper presents a new pattern recognition system for Chinese spirit identification by using the polymer quartz piezoelectric crystal sensor based e-nose. The sensors are designed based on quartz crystal microbalance(QCM) principle,and they could capture different vibration frequency signal values for Chinese spirit identification. For each sensor in an8-channel sensor array, seven characteristic values of the original vibration frequency signal values, i.e., average value(A),root-mean-square value(RMS), shape factor value(S_f), crest factor value(C_f), impulse factor value(I_f), clearance factor value(CL_f), kurtosis factor value(K_v) are first extracted. Then the dimension of the characteristic values is reduced by the principle components analysis(PCA) method. Finally the back propagation(BP) neutral network algorithm is used to recognize Chinese spirits. The experimental results show that the recognition rate of six kinds of Chinese spirits is 93.33% and our proposed new pattern recognition system can identify Chinese spirits effectively. 展开更多
关键词 new pattern recognition system polymer quartz piezoelectric crystal sensor e-nose principle com-ponents analysis (PCA) back propagation (BP) algorithm Chinese spirit identification
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A CLASS OF COLLINEAR SCALING ALGORITHMS FOR UNCONSTRAINED OPTIMIZATON
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作者 盛松柏 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1997年第2期219-230,共12页
A Class of Collinear Scaling Algorithms for Unconstrained Optimization. An appealing approach to the solution of nonlinear optimization problems based on conic models of the objective function has been in troduced by ... A Class of Collinear Scaling Algorithms for Unconstrained Optimization. An appealing approach to the solution of nonlinear optimization problems based on conic models of the objective function has been in troduced by Davidon (1980). It leads to a broad class of algorithms which can be considered to generalize the existing quasi-Newton methods. One particular member of this class has been deeply discussed by Sorensen (1980), who has proved some interesting theoretical properties. In this paper, we generalize Sorensen’s technique to Spedicato three-parameter family of variable-metric updates. Furthermore, we point out that the collinear scaling three- parameter family is essentially equivalent to the Spedicato three-parameter family. In addition, numerical expriments have been carried out to compare some colliner scaling algorithms with a straightforward implementation of the BFGS quasi-Newton method. 展开更多
关键词 UNCONSTRAINED optimization CONIC models COLLINEAR scaling quasi-newton algorithms.
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Study of improved gray predictive PID control algorithm 被引量:1
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作者 XIE Shou-yong LI Xi-wen +1 位作者 YANG Shu-zi YANG Ming-jin 《重庆邮电大学学报(自然科学版)》 北大核心 2009年第2期189-191,共3页
According to these characteristics of the movement of the special platform servo,a new improved grey predictive PID control algorithm was proposed based on the grey predictive PID,and then the algorithm was simulated ... According to these characteristics of the movement of the special platform servo,a new improved grey predictive PID control algorithm was proposed based on the grey predictive PID,and then the algorithm was simulated by MATLAB.As a result that it can improve the response speed and stability of the system,and meet the demand of the system. 展开更多
关键词 PID控制算法 灰色预测 MATLAB 算法模拟 反应速度 系统 伺服
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Density Structure of the Papua New Guinea-Solomon Arc Subduction System
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作者 XU Chong XING Junhui +3 位作者 GONG Wei ZHANG Hao XU Haowei XU Xiaoyu 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第5期1269-1276,共8页
The Papua New Guinea-Solomon(PN-SL)arc is one of the regions with active crustal motions and strong geological actions.Thus,its complex subduction system makes it an ideal laboratory for studying the initiation mechan... The Papua New Guinea-Solomon(PN-SL)arc is one of the regions with active crustal motions and strong geological actions.Thus,its complex subduction system makes it an ideal laboratory for studying the initiation mechanism of plate subduction.However,the PN-SL subduction system has not yet been sufficiently studied,and its density structure has yet to be revealed.In this paper,we used the free-air gravity data,Parker-Oldenburg density surface inversion method,and the genetic algorithm density inversion method to obtain the density structure of an approximately 1000-km-long northwest-southeast line crossing the PN-SL subduction system under the constraints of the CRUST1.0 global crustal model,onshore seismic data,and the LLNL-G3Dv3 global P-wave velocity model.The density structure shows that density differences between the plates on the two sides of the trench could play a significant role in plate subduction. 展开更多
关键词 Papua new Guinea-Solomon plate subduction gravity anomaly density structure genetic algorithm
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Identification of Factors Influencing Out-of-county Hospitalizations in the New Cooperative Medical Scheme
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作者 Wan-rong LU Wen-jie WANG +6 位作者 Chen LI Huang-guo XIONG Yi-lei MA Mi LUO Hong-yu PENG Zong-fu MAO Ping YIN 《Current Medical Science》 SCIE CAS 2019年第5期843-851,共9页
Summary:Throughout the duration of the New Cooperative Medical Scheme(NCMS),it was found that an increasing number of rural patients were seeking out-of^county medical treatment,which posed a great burden on the NCMS ... Summary:Throughout the duration of the New Cooperative Medical Scheme(NCMS),it was found that an increasing number of rural patients were seeking out-of^county medical treatment,which posed a great burden on the NCMS fund.Our study was conducted to examine the prevalence of out-of^county hospitalizations and its related factors,and to provide a scientific basis for follow?up health insurance policies.A total of 215 counties in central and western China from 2008 to 2016 were selected.The total out-of-county hospitalization rate in nine years was 16.95%,which increased from 12.37%in 2008 to 19.21%in 2016 with an average annual growth rate of 5.66%.Its related expenses and compensations were shown to increase each year,with those in the central region being higher than those in the western region.Stepwise logistic regression reveals that the increase in out-of-county hospitalization rate was associated with region(XI),rural population(X2),per capita per year net income(X3),per capita gross domestic product(GDP)(X4),per capita funding amount of NCMS(X5),compensation ratio of out-of^county hospitalization cost(X6),per time average in-county(X7)and out-of-county hospitalization cost(X8).According to Bayesian network(BN),the marginal probability of high out-of^county hospitalization rate was as high as 81.7%.Out-of^county hospitalizations were directly related to X8,X3,X4 and X6.The probability of high out-of-county hospitalization obtained based on hospitalization expenses factors,economy factors,regional characteristics and NCMS policy factors was 95.7%,91.1%,93.0% and 88.8%,respectively.And how these factors affect out-of-county hospitalization and their interrelationships were found out.Our findings suggest that more attention should be paid to the influence mechanism of these factors on out-of-county hospitalizations,and the increase of hospitalizations outside the county should be reasonably supervised and controlled and our results will be used to help guide the formulation of proper intervention policies. 展开更多
关键词 new COOPERATIVE MEDICAL Scheme(NCMS) out-of-county hospitalization rate Bayesian network(BN) Max-Min HILL-CLIMBING algorithm related factors
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On Over-Relaxed Proximal Point Algorithms for Generalized Nonlinear Operator Equation with (A,η,m)-Monotonicity Framework
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作者 Fang Li 《International Journal of Modern Nonlinear Theory and Application》 2012年第3期67-72,共6页
In this paper, a new class of over-relaxed proximal point algorithms for solving nonlinear operator equations with (A,η,m)-monotonicity framework in Hilbert spaces is introduced and studied. Further, by using the gen... In this paper, a new class of over-relaxed proximal point algorithms for solving nonlinear operator equations with (A,η,m)-monotonicity framework in Hilbert spaces is introduced and studied. Further, by using the generalized resolvent operator technique associated with the (A,η,m)-monotone operators, the approximation solvability of the operator equation problems and the convergence of iterative sequences generated by the algorithm are discussed. Our results improve and generalize the corresponding results in the literature. 展开更多
关键词 new Over-Relaxed Proximal Point algorithm Nonlinear OPERATOR Equation with (A η m)-Monotonicity FRAMEWORK Generalized RESOLVENT OPERATOR Technique Solvability and Convergence
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Improvement and Comparative Analysis of Similartaxis Operator of Mind Evolutionary Algorithm for Multivariable Continuous State Space
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作者 Jin Wang Chuanlong Wang 《通讯和计算机(中英文版)》 2011年第2期83-87,共5页
关键词 思维进化算法 多变量分析 状态空间 多元正态分布 搜索策略 MEA 分布策略 收敛速度
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数据、算力和算法结合反映新质生产力的数字化发展水准 被引量:11
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作者 任保平 豆渊博 《浙江工商大学学报》 CSSCI 北大核心 2024年第3期91-100,共10页
数字经济的发展促进新的劳动主体、新的生产工具和新的生产要素不断涌现,为人们认识世界和改造世界创造了新模式,新质生产力的数字化发展是新质生产力在数字经济领域的表现。数字经济时代,数据作为新质生产力数字化发展的新要素,算力体... 数字经济的发展促进新的劳动主体、新的生产工具和新的生产要素不断涌现,为人们认识世界和改造世界创造了新模式,新质生产力的数字化发展是新质生产力在数字经济领域的表现。数字经济时代,数据作为新质生产力数字化发展的新要素,算力体现新质生产力数字化发展的新动能,算法反映新质生产力数字化发展的新优势,数据、算力和算法的结合反映了新质生产力的数字化发展水准,形成数字时代的新质生产力。新发展阶段,数据、算力和算法的结合首先引起生产力的决策革命,其次引起生产力的工具革命、劳动力革命、生产要素革命和技术—经济范式革命,进一步推动新质生产力的数字化发展。在全球经济新周期的背景下,提高新质生产力的数字化发展水平已经成为推动经济社会高质量发展的关键力量。 展开更多
关键词 新质生产力 数据+算力+算法 数字技术 智能化工具
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采用融合遗传算法的高速公路服务区综合能源系统优化调度研究 被引量:1
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作者 李杰 高爽 +1 位作者 袁博兴 张懿璞 《西安交通大学学报》 EI CAS CSCD 北大核心 2024年第5期200-211,共12页
为达成“碳中和”目标愿景、促进公路交通系统与新能源的融合,以高速公路服务区为研究对象,考虑服务区内电、冷、热、气共4种负荷需求,构建了包含风光发电的新能源发电方式和电转气设备的高速公路服务区综合能源系统。在此基础上,以风... 为达成“碳中和”目标愿景、促进公路交通系统与新能源的融合,以高速公路服务区为研究对象,考虑服务区内电、冷、热、气共4种负荷需求,构建了包含风光发电的新能源发电方式和电转气设备的高速公路服务区综合能源系统。在此基础上,以风电、光伏出力日前预测和多能负荷日前消耗为输入,各能源设备出力及购能分配为输出,以总成本最低为目标函数,考虑能量平衡、设备安全、运行状态等约束,建立了高速公路服务区综合能源系统优化调度模型。针对高速公路服务区综合能源系统调度问题,设计了遗传-序列二次规划融合优化算法,并以某服务区夏季典型日为例进行验证。结果表明:所构建的调度系统能够有效消纳可再生能源出力,协调外部购电、购气的比例,最终达到降低成本的效果;所提融合算法的调度结果与传统遗传算法、传统序列二次规划算法相比,在成本上分别降低了11.52%、0.70%,求解耗时仅为传统遗传算法的6.7%,独立性相比传统序列二次规划算法得到了提高。 展开更多
关键词 高速公路服务区 新能源 遗传-序列二次规划算法 优化调度 电转气
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基于改进KNN算法的新能源发电单元运行状态识别 被引量:2
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作者 史林军 戴滔 +5 位作者 劳文洁 吴峰 林克曼 李杨 朱玲 黄锡芳 《电力自动化设备》 EI CSCD 北大核心 2024年第5期65-72,共8页
目前识别发电单元运行状态的研究较少,数据来源以数据采集与监控系统为主,采集速度较慢。为此,提出了一种基于发电单元机端电气量数据并融合改进k近邻(KNN)算法的新能源发电单元状态识别方法,直接采集机端电气量数据用于快速判断发电单... 目前识别发电单元运行状态的研究较少,数据来源以数据采集与监控系统为主,采集速度较慢。为此,提出了一种基于发电单元机端电气量数据并融合改进k近邻(KNN)算法的新能源发电单元状态识别方法,直接采集机端电气量数据用于快速判断发电单元状态。提出KNN算法的改进策略,克服了传统KNN算法准确度低、识别速度慢的缺点。利用电力系统分析综合程序获取用于状态识别的发电单元机端电气量数据,利用改进策略对数据进行预处理,并对比传统KNN算法、逐条使用改进策略的KNN算法对新能源发电单元状态识别的耗时与准确度。结果表明所提算法较传统算法的识别准确度和速度明显提升,能满足稳定控制过程中对新能源发电单元的状态感知需求。 展开更多
关键词 状态识别 改进KNN算法 新能源发电单元 特征提取 特征加权
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含新能源和电动汽车充电站并网的主动配电网无功优化模型 被引量:2
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作者 江智军 袁轩 +2 位作者 邱文浩 黄礼才 何伟 《电力系统及其自动化学报》 CSCD 北大核心 2024年第2期116-125,共10页
针对新能源和电动汽车充电站规模化并网引起的无功优化问题,首先建立以主动配电网运行成本和电压偏差最小,系统稳定性最优的多目标无功优化模型。其次,基于PV曲线上、下半支解的接近程度,提出一种新的静态电压稳定性指标,以改善系统电... 针对新能源和电动汽车充电站规模化并网引起的无功优化问题,首先建立以主动配电网运行成本和电压偏差最小,系统稳定性最优的多目标无功优化模型。其次,基于PV曲线上、下半支解的接近程度,提出一种新的静态电压稳定性指标,以改善系统电压稳定性。最后,采用具有交叉反馈机制的混合优化算法对模型进行求解,并提出一种基于Tent混沌映射和自适应变异算子的改进飞蛾扑火算法提高求解效率。仿真结果表明,所提模型在降低系统运行成本,减少电压波动的同时,还能提高系统稳定性,且该混合优化算法能够快速、准确地求解混合整数的非凸、非线性优化模型。 展开更多
关键词 新能源 电动汽车 无功优化 主动配电网 混合优化算法
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以高水平法治促进新质生产力发展 被引量:2
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作者 陈兵 《学术前沿》 CSSCI 北大核心 2024年第11期86-93,共8页
新质生产力以全要素生产率大幅提升为核心标志,特点是创新,关键在质优,本质是先进生产力。数据与算法、算力作为质优的创新型要素,优化其配置成为提高全要素生产率的关键一环。在优化要素配置过程中,数据流通、算法开发与算力协同都离... 新质生产力以全要素生产率大幅提升为核心标志,特点是创新,关键在质优,本质是先进生产力。数据与算法、算力作为质优的创新型要素,优化其配置成为提高全要素生产率的关键一环。在优化要素配置过程中,数据流通、算法开发与算力协同都离不开法治的支撑,同时,整体营商环境的持续优化也需要法治的保障。从实践出发,良法善治在消除和打通新质生产力发展的堵点痛点方面能发挥积极作用,以促进新型生产关系适配新质生产力发展。为此,需在法治框架下健全数据基础制度,推动数据要素有序开放流通,完善人工智能算法治理体系和算力协同机制,持续优化营商环境,为新质生产力发展提供质优生态。 展开更多
关键词 新质生产力 数据流通 算法规制 算力协同 良法善治
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