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Multiple parametric Marcinkiewicz integrals with mixed homogeneity along surfaces
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作者 SHEN Jia-wei HE Shao-yong CHEN Jie-cheng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第3期413-428,共16页
In this paper, the multiple parametric Marcinkiewicz integral operators with mixed homogeneity along surfaces are studied. The Lp-mapping properties for such operators are obtained under the rather weakened size condi... In this paper, the multiple parametric Marcinkiewicz integral operators with mixed homogeneity along surfaces are studied. The Lp-mapping properties for such operators are obtained under the rather weakened size conditions on the integral kernels both on the unit sphere and in the radial direction. The main results essentially improve and extend certain previous results. 展开更多
关键词 parametric Marcinkiewicz integrals rough kernels mixed homogeneity product spaces
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ON THE MIXED RADIAL-ANGULAR INTEGRABILITY OF MARCINKIEWICZ INTEGRALS WITH ROUGH KERNELS 被引量:2
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作者 刘荣辉 刘风 伍火熊 《Acta Mathematica Scientia》 SCIE CSCD 2021年第1期241-256,共16页
This paper studies the mixed radial-angular integrability of parametric Marcinkiewicz integrals along"polynomial curves".Under the assumption that the kernels satisfy certain rather weak size conditions on t... This paper studies the mixed radial-angular integrability of parametric Marcinkiewicz integrals along"polynomial curves".Under the assumption that the kernels satisfy certain rather weak size conditions on the unit sphere with radial roughness,the authors prove that such operators are bounded on the mixed radial-angular spaces.Meanwhile,corresponding vector-valued versions are also obtained. 展开更多
关键词 Marcinkiewicz integrals rough kernels mixed radial-angular spaces
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Powder mixed electrochemical discharge process for micro machining of C103 niobium alloy
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作者 Niladri Mandal Nitesh Kumar Alok Kumar Das 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第8期84-101,共18页
This work demonstrates the viability of the powder-mixed micro-electrochemical discharge machining(PMECDM) process to fabricate micro-holes on C103 niobium-based alloy for high temperature applications.Three processes... This work demonstrates the viability of the powder-mixed micro-electrochemical discharge machining(PMECDM) process to fabricate micro-holes on C103 niobium-based alloy for high temperature applications.Three processes are involved simultaneously i.e.spark erosion,chemical etching,and abrasive grinding for removal of material while the classical electrochemical discharge machining process involves double actions i.e.spark erosion,and chemical etching.The powder-mixed electrolyte process resulted in rapid material removal along with a better surface finish as compared to the classical microelectrochemical discharge machining(MECDM).Further,the results are optimized through a multiobjective optimization approach and study of the surface topography of the hole wall surface obtained at optimized parameters.In the selected range of experimental parameters,PMECDM shows a higher material removal rate(MRR) and lower surface roughness(R_(a))(MRR:2.8 mg/min and R_(a) of 0.61 μm) as compared to the MECDM process(MRR:2.01 mg/min and corresponding Raof 1.11 μm).A detailed analysis of the results is presented in this paper. 展开更多
关键词 Micro-electrochemical discharge machining C103 niobium alloy Surface integrity Material removal rate Hybrid powder mixed ECDM
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A NOTE ON SINGULAR INTEGRALS WITH DOMINATING MIXED SMOOTHNESS IN TRIEBEL-LIZORKIN SPACES
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作者 Hung Viet LE 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1331-1344,共14页
Let h, be a measurable function defined on R^+ ×R^+. Let Ω ∈ L(log L^+)^υq (S^n1-1 × S^n2-1) (1≤ υq ≤ 2) be homogeneous of degree zero and satisfy certain cancellation conditions. We show that... Let h, be a measurable function defined on R^+ ×R^+. Let Ω ∈ L(log L^+)^υq (S^n1-1 × S^n2-1) (1≤ υq ≤ 2) be homogeneous of degree zero and satisfy certain cancellation conditions. We show that the singular integral Tf(x1,x2)=p.v.∫∫R^n1+n2 Ω(y′1,y′2)h(|y1|,|y2|)/|y1|^n1|y2|^n2 f(x1-y1,x2-y2)dy1dy2maps from Sp,q^α1,α2F(R^n1×R^n2)boundedly to itself for 1 〈 p, q 〈 ∞, α1, α2 ∈R. 展开更多
关键词 singular integrals Marcinkiewicz integrals mixed smoothness Triebel-Lizorkin spaces
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EXISTENCE OF SOLUTIONS FOR MIXED MONOTONE IMPULSIVE VOLTERRA INTEGRAL EQUATIONS IN BANACH SPACES 被引量:6
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作者 陈芳启 《Acta Mathematica Scientia》 SCIE CSCD 1998年第4期371-378,共8页
This paper studies the existence of solutions for mixed monotone impulsive Volterra integral equations on the infinite interval R+ with an infinite number of moments of impulse effect in Banach spaces. By using the mi... This paper studies the existence of solutions for mixed monotone impulsive Volterra integral equations on the infinite interval R+ with an infinite number of moments of impulse effect in Banach spaces. By using the mixed monotone iterative technique and Monch fixed point theorem, Some existence theorems of solutions and coupled minimal and maximal quasisolutions are obtained. Finally, an example is worked out. 展开更多
关键词 impulsive Volterra integral equation mixed monotone iterative technique Monch fixed point theorem cone and partial ordering
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GLOBAL APPROXIMATION FOR A CLASS OF GENERALIZED MIXED EXPONENTIAL TYPE INTEGRAL OPERATORS IN POLYNOMIAL WEIGHT SPACES
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作者 Li Hong(Dept. of Math., Huazhong Univ. of Sci. and Tech.Wuhan 430000) 《数学研究》 CSCD 1994年第1期92-96,共5页
GLOBALAPPROXIMATIONFORACLASSOFGENERALIZEDMIXEDEXPONENTIALTYPEINTEGRALOPERATORSINPOLYNOMIALWEIGHTSPACES¥LiHon... GLOBALAPPROXIMATIONFORACLASSOFGENERALIZEDMIXEDEXPONENTIALTYPEINTEGRALOPERATORSINPOLYNOMIALWEIGHTSPACES¥LiHong(Dept.ofMath.,Hu... 展开更多
关键词 混合展开积分算子 加权空间 一致连续 有界线性
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Critical Exercise Price for American Floating Strike Lookback Option in a Mixed Jump-Diffusion Model 被引量:4
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作者 YANG Zhao-qiang 《Chinese Quarterly Journal of Mathematics》 2018年第3期240-259,共20页
This paper studies the critical exercise price of American floating strike lookback options under the mixed jump-diffusion model. By using It formula and Wick-It-Skorohod integral, a new market pricing model estab... This paper studies the critical exercise price of American floating strike lookback options under the mixed jump-diffusion model. By using It formula and Wick-It-Skorohod integral, a new market pricing model established under the environment of mixed jumpdiffusion fractional Brownian motion. The fundamental solutions of stochastic parabolic partial differential equations are estimated under the condition of Merton assumptions. The explicit integral representation of early exercise premium and the critical exercise price are also given, then the American floating strike lookback options factorization formula is obtained, the results is generalized the classical Black-Scholes market pricing model. 展开更多
关键词 mixed JUMP-DIFFUSION fractional BROWNIAN motion Wick-Ito-Skorohod integral market pricing model option factorization CRITICAL exercise price
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MIXED HARDY SPACES AND THEIR APPLICATIONS 被引量:2
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作者 丁卫 朱月萍 《Acta Mathematica Scientia》 SCIE CSCD 2020年第4期945-969,共25页
Multi-parameter mixed Hardy space Hpmix is introduced by a new discrete Calderon's identity.As an application,we obtain the Hmix^p→ L^p(R^n1+n2)boundedness of operators in the mixed Journe’s class.
关键词 mixed Hardy spaces discrete Calderon's identity singular integral operators ATOMS
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Effect of moxibustion combined with five‑element music therapy on postoperative pain relief after mixed hemorrhoid operation 被引量:7
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作者 Li‑Yuan WANG Hai‑Yun GAI +1 位作者 Yu WEN Ming‑Hui MA 《Journal of Integrative Nursing》 2020年第1期22-26,共5页
Objective:To investigate the effect of moxibustion combined with five‑element music therapy on the postoperative pain relief of patients undergoing surgical operation for mixed hemorrhoid with damp‑heat syndrome.Metho... Objective:To investigate the effect of moxibustion combined with five‑element music therapy on the postoperative pain relief of patients undergoing surgical operation for mixed hemorrhoid with damp‑heat syndrome.Methods:Totally,159 patients meeting the inclusion criteria were assigned to the control group,study group 1,and study group 2,with 53 cases in each group.All patients received routine care after surgical treatment,including acupoint application and Chinese herbal fumigation.In addition,patients in the study group 1 received moxibustion,and those in the study group 2 were given moxibustion combined with five‑element music therapy.The degree of postoperative pain was evaluated using visual analog scale(VAS).Results:There was no significant difference in VAS score on pain during dressing changes among three groups(P>0.05).After 3,5,and 7 days of intervention,there was a significant difference in VAS score on pain at rest among three groups(P<0.001),and VAS score in the study group 2 was lower than that in the study group 1 and the control group after 3 and 5 days of intervention,respectively(P<0.05).Conclusion:Moxibustion combined with five‑element music therapy is effective to relieve the postoperative pain of patients undergoing a surgical operation for mixed hemorrhoids with damp‑heat syndrome. 展开更多
关键词 Five‑element music therapy five‑tone therapy mixed hemorrhoid MOXIBUSTION nursing of integrated traditional Chinese and western medicine pain
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MIXED LIPSCHITZ SPACES AND THEIR APPLICATIONS 被引量:1
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作者 何少勇 陈杰诚 《Acta Mathematica Scientia》 SCIE CSCD 2022年第2期690-714,共25页
The purpose of this paper is to introduce bi-parameter mixed Lipschitz spaces and characterize them via the Littlewood-Paley theory.As an application,we derive a boundedness criterion for singular integral operators i... The purpose of this paper is to introduce bi-parameter mixed Lipschitz spaces and characterize them via the Littlewood-Paley theory.As an application,we derive a boundedness criterion for singular integral operators in a mixed Journéclass on mixed Lipschitz spaces.Key elements of the paper are the development of the Littlewood-Paley theory for a special mixed Besov spaces,and a density argument for the mixed Lipschitz spaces in the weak sense. 展开更多
关键词 mixed Lipschitz spaces Littlewood-Paley theory singular integral operators
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STABILITY MARGIN OF SYSTEMS WITH MIXED UNCERTAINTIES UNDER THE IQC DESCRIPTIONS
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作者 董海荣 耿志勇 +1 位作者 王金枝 黄琳 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第11期1274-1281,共8页
Stability perturbation bounds problem for systems with mixed uncertainties is discussed. It is supposed that the linear part in the forward loop is of parametric uncertainties described by interval perturbation mode, ... Stability perturbation bounds problem for systems with mixed uncertainties is discussed. It is supposed that the linear part in the forward loop is of parametric uncertainties described by interval perturbation mode, and that the nonlinear part in the feedback loop is characterized by an integral quadratic constraint (IQC). The definition of stability margin under the interval perturbation mode is given by using the Minkowski functional. The infinite stability checking problem of the mixed uncertain system can be converted to finite or one dimensional stability checking for different structures of the IQC multipliers based on the concepts of biconvex and convex-concave junctions and their properties. The result is illustrated to be efficient through an example. 展开更多
关键词 system with mixed uncertainty perturbation margin integral quadratic constraint parametric uncertainty stability checking
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I/O IMAGE^(TM) Mixed System简介
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作者 胡杨 阎锋 马永海 《物探装备》 2003年第1期68-69,共2页
I/O IMAGE^(TM) Mixed System仪器运用了高速发展的微机和网络技术,简化了硬件结构,并成功地将无线电技术和有线技术结合在一起。施工中可以根据不同的地形,灵活地选择有线、无线或有线无线混合进行工作。文中简要地介绍了I/O IMAGE^(TM... I/O IMAGE^(TM) Mixed System仪器运用了高速发展的微机和网络技术,简化了硬件结构,并成功地将无线电技术和有线技术结合在一起。施工中可以根据不同的地形,灵活地选择有线、无线或有线无线混合进行工作。文中简要地介绍了I/O IMAGE^(TM)Mixed System的主要特点。 展开更多
关键词 遥测地震仪器 有线无线混合 集成 I/O-IMAGE^TM-mixedSystem仪器
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Multiframe track-before-detect method based on velocity filtering in mixed coordinates
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作者 WANG Liangliang ZHOU Gongjian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第2期247-258,共12页
In this paper,a velocity filtering based track-before-detect algorithm in mixed coordinates is presented to address the problem of integration loss caused by inaccurate motion model in polar coordinate sensors.Since t... In this paper,a velocity filtering based track-before-detect algorithm in mixed coordinates is presented to address the problem of integration loss caused by inaccurate motion model in polar coordinate sensors.Since the motion of a con-stant velocity(CV)target is better modeled in Cartesian coordi-nates,the search of measurements for integration in polar sensor coordinates is carried out according to the CV model in Cartesian coordinates instead of an approximate model in polar sensor coordinates.The position of each cell is converted into Cartesian coordinates and predicted according to an assumed velocity.Then,the predicted Cartesian position is converted back to polar sensor coordinates for multiframe accumulation.The use of the correct model improves integration effectiveness and consequently improves algorithm performance.To handle the weak target with unknown velocity,a velocity filter bank in mixed coordinates is presented.The influence of velocity mis-match on the performance of filter bank is analyzed,and an effi-cient strategy for filter bank design is proposed.Numerical re-sults are presented to demonstrate the effectiveness of the pro-posed algorithm. 展开更多
关键词 mixed coordinate approach velocity filtering multiframe integration weak target detection polar sensor coordinate
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Estimating the shareholder's terminal payoff based on insurer's solvency ratio in mixed fractional Brownian market
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作者 XIA Deng-feng FEI Wei-yin LIU Hong-jian 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2015年第3期317-324,共8页
This paper studies the insurer’s solvency ratio model in a class of mixed fractional Brownian motion(MFBM) market, where the prices of assets follow a Wick-It? stochastic differential equation driven by the MFBM, by ... This paper studies the insurer’s solvency ratio model in a class of mixed fractional Brownian motion(MFBM) market, where the prices of assets follow a Wick-It? stochastic differential equation driven by the MFBM, by the method of the stochastic calculus of the MFBM and the pricing formula of European call option for the MFBM, the explicit formula for the expected present value of shareholders’ terminal payoff is given. The model extends the existing results. 展开更多
关键词 mixed fractional Brownian motion Wick-It stochastic integral solvency ratio financial distress cost
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A new two-mode thermo- and squeezing-mixed optical field
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作者 周军 范洪义 宋军 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第7期27-30,共4页
We propose a new two-mode thermo-and squeezing-mixed optical field, described by the new density operator ρ=1-e^f-|g|^2 e^ga^+b^+e^fa^+a|0〉 f_(bb) 〈0| e^(g*ab), where |0〉_(bb) 〈0| is the b-mode va... We propose a new two-mode thermo-and squeezing-mixed optical field, described by the new density operator ρ=1-e^f-|g|^2 e^ga^+b^+e^fa^+a|0〉 f_(bb) 〈0| e^(g*ab), where |0〉_(bb) 〈0| is the b-mode vacuum, e ^fa^+arepresents the thermo-field, and e^ga^+b^+ indicates squeezing. The photon statistics for ρ is studied by virtue of the method of integration within ordered product(IWOP) of operators. Such a field can be generated when a two-mode squeezed state passes through a one-mode dissipation channel. 展开更多
关键词 thermo-and squeezing-mixing new optical field photon statistics integration within ordered product(IWOP) method
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基于混合式教学理念的急救技能模块整合教学在中医临床专业研究生急救能力培养中的作用
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作者 刘福生 吴笛 +5 位作者 黄坡 王苏妹 郑香春 陈孟准 崔瑞刚 方晓磊 《中国中医急症》 2024年第2期328-331,共4页
目的评价基于混合式教学理念的急救技能模块整合教学在中医临床专业学位研究生急救技能培养中的效果。方法根据入科月份随机将2022年9月至2023年8月北京中医药大学东方医院急诊科轮转的中医临床专业硕士研究生60名分为传统教学组和混合... 目的评价基于混合式教学理念的急救技能模块整合教学在中医临床专业学位研究生急救技能培养中的效果。方法根据入科月份随机将2022年9月至2023年8月北京中医药大学东方医院急诊科轮转的中医临床专业硕士研究生60名分为传统教学组和混合式教学组各30例。评价入科、出科成绩,急救技能成绩及教学满意度。结果混合式教学组的理论成绩[(84.07±9.89)分]和技能成绩[(84.77±8.55)分]高于传统教训的理论成绩[(78.93±9.85)分]和技能成绩[(80.27±8.17)分](P<0.05);混合式教学组的教学满意度(90%)和传统教学组(80%)差异无统计学意义(P>0.05);混合式教学组急救能力获得感评分[8(8,8)分]高于传统教学组[7(7,8)分](P<0.05)。结论基于混合式教学理念的急救技能模块整合教学有助于提高中医临床专业学位研究生急救能力。 展开更多
关键词 急救技能 混合式教学 模块整合 专业学位研究生 教学实践
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基于主动尾流控制的风电机群协同优化调度
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作者 胡阳 张冲 +1 位作者 房方 刘吉臻 《动力工程学报》 CAS CSCD 北大核心 2024年第4期566-574,共9页
针对机组间尾流效应严重影响风电机组发电效率的问题,提出了风电机组安全偏航约束计算方法、尾流特性混合半机理建模方法以及风电机群多目标协同优化调度方法。基于FAST.FARM平台完善了多自由度可控机组与尾流的动态交互集成仿真环境,... 针对机组间尾流效应严重影响风电机组发电效率的问题,提出了风电机组安全偏航约束计算方法、尾流特性混合半机理建模方法以及风电机群多目标协同优化调度方法。基于FAST.FARM平台完善了多自由度可控机组与尾流的动态交互集成仿真环境,对比分析了2台机组串列式排布以及华东地区某海上风电场7台机组实际排布下的协同运行优化性能。结果表明:所建立的集成仿真模型能够合理表征风电机群与空气流场的多领域动态交互特性,所提方法能够有效提升风电机群发电效能,促进经济效益、资源利用和成本控制的均衡优化。 展开更多
关键词 风力发电 多领域集成仿真 主动偏航控制 混合半机理建模 多目标优化调度
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T应力作用下的J积分理论研究
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作者 谌赫 魏豪杰 王文胜 《河南科技大学学报(自然科学版)》 北大核心 2024年第2期44-55,M0005,共13页
T应力是表征裂尖应力场所必需的物理量之一,在其作用下J积分的性质有待研究。推导了J积分在考虑T应力情况下的表达式,采用数值模拟方法在Ⅰ型、Ⅱ型和Ⅰ+Ⅱ复合型加载工况下对该表达式进行验证,给出一种基于J积分的裂尖应力场参数计算... T应力是表征裂尖应力场所必需的物理量之一,在其作用下J积分的性质有待研究。推导了J积分在考虑T应力情况下的表达式,采用数值模拟方法在Ⅰ型、Ⅱ型和Ⅰ+Ⅱ复合型加载工况下对该表达式进行验证,给出一种基于J积分的裂尖应力场参数计算方法。理论推导证明,J1积分的路径守恒性不受T应力影响,但J2积分的数值与积分路径起止点到裂尖距离r的平方根之间满足线性关系,J2-r曲线的系数与T应力相关。有限元仿真结果表明,试样裂纹长度对J积分的影响较为显著,网格尺寸对J积分计算结果的影响很小;相同载荷工况下,不同尺寸试样的J积分数值不同,但J2-r曲线的变化趋势与理论推导的表达式相符;在Ⅱ型和Ⅰ+Ⅱ复合型载荷工况下,T应力的求解精度较高,而在Ⅰ型载荷工况下,J2≈0,受舍入误差等因素影响,求解精度降低。 展开更多
关键词 J积分 T应力 复合型断裂 数值模拟
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基于异质堆叠集成学习的脱硫剂加入量预测
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作者 吴经纬 方一飞 +3 位作者 但斌斌 容芷君 都李平 罗钟邱 《炼钢》 CAS 北大核心 2024年第3期1-7,共7页
KR搅拌法是铁水预脱硫的重要工艺之一,但在脱硫过程中脱硫剂的加入量主要依赖于人工经验控制,导致一次脱硫命中率较低,铸坯质量不稳定。为准确控制脱硫剂加入量,提高一次脱硫命中率,提出一种基于异质堆叠集成学习的脱硫剂加入量预测方... KR搅拌法是铁水预脱硫的重要工艺之一,但在脱硫过程中脱硫剂的加入量主要依赖于人工经验控制,导致一次脱硫命中率较低,铸坯质量不稳定。为准确控制脱硫剂加入量,提高一次脱硫命中率,提出一种基于异质堆叠集成学习的脱硫剂加入量预测方法。首先,进行数据清洗,采用LOF算法结合专家经验剔除异常值。其次,采用最大信息系数结合斯皮尔曼秩相关系数进行特征筛选。最后,引入堆叠集成算法,基于评价指标和误差相关性分析优选模型的不同基学习器,并采用Optuna算法为基学习器寻找最优参数组合,建立异质堆叠集成预测模型。以现场采集的脱硫数据作为样本进行实例分析,结果表明,模型的决定系数(R^(2))为91.6%,均方根误差(RMSE)为197.79,平均绝对误差(MAE)为117.14,平均绝对百分比误差(MAPE)为6.95%。 展开更多
关键词 KR搅拌法 脱硫剂加入量 特征筛选 Optuna 堆叠集成
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基于混合整数规划的智能车横纵向一体化滚动优化决策
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作者 戴启坤 刘俊 +2 位作者 郭洪艳 陈虹 孙义 《控制理论与应用》 EI CAS CSCD 北大核心 2024年第1期21-29,共9页
本文针对智能车辆的行为决策问题,设计了基于混合整数规划的智能车横纵向一体化滚动优化决策方法.该方法首先将纵向车速表示为非整数,将期望车道表示为整数控制量,建立了混合整数智能车决策简化模型;然后,设计了横纵向一体化滚动优化决... 本文针对智能车辆的行为决策问题,设计了基于混合整数规划的智能车横纵向一体化滚动优化决策方法.该方法首先将纵向车速表示为非整数,将期望车道表示为整数控制量,建立了混合整数智能车决策简化模型;然后,设计了横纵向一体化滚动优化决策方法,决策出纵向车速和换道动作,根据系统输出与非线性约束的时域关系证明了优化问题的递归可行性并通过遗传算法求解非线性混合整数规划优化问题.基于车辆动力学仿真软件veDYNA和Simulink进行了联合仿真,并在红旗E-HS3智能车上开展了实车试验,结果表明,本文提出的基于混合整数规划的智能车横纵向一体化决策方法能够实现超车、避障、跟车、停车和弯道工况下的行为决策. 展开更多
关键词 决策 混合整数规划 模型预测控制 横纵向一体化 决策模型 自动驾驶
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