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Analysis of incompressible viscous fluid flow in convergent and divergent channels with a hybrid meta-heuristic optimization techniques in ANN:An intelligent approach 被引量:2
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作者 ASLAM Muhammad Naeem RIAZ Arshad +3 位作者 SHAUKAT Nadeem ALI Shahzad AKRAM Safia BHATTI M.M. 《Journal of Central South University》 SCIE EI CAS CSCD 2023年第12期4149-4167,共19页
In this research article,we introduce a numerical investigation through artificial neural networks(ANN)integrated with evolutionary algorithm especially Archimedean optimization algorithm(AOA)hybrid with the water cyc... In this research article,we introduce a numerical investigation through artificial neural networks(ANN)integrated with evolutionary algorithm especially Archimedean optimization algorithm(AOA)hybrid with the water cycle algorithm(WCA)to address and enhance the analysis of the non-linear magneto-hydrodynamic(MHD)Jeffery-Hamel problem,especially stretching/shrinking in convergent and divergent channel.This combined technique is referred to as ANN-AOA-WCA.The complex nonlinear magneto-hydrodynamic Jeffery-Hamel problem based partial differential equations are transformed into non-linear system of ordinary differential equations for velocity and temperature.We formulate the ANN based fitness function to find the solution of non-linear differential.Subsequently,we employ a novel hybridization of AOA and WCA(AOA-WCA)to optimize the ANN based fitness function and identify the best optimal weights and biases for ANN.To demonstrate the effectiveness and versatility of our proposed hybrid method,we explore MHD models across a range of Reynolds numbers,channel angles and stretchable boundary value leading to the development of two distinct cases.ANN-AOA-WCA numerical results closely align with reference solutions(NDSOLVE)and the absolute error between NDSOLVE and ANN-AOA-WCA is up to 3.35´10^(-8),particularly critical to the understanding of stretchable convergent and divergent channel.Furthermore,to validate the ANN-AOA-WCA technique,we conducted a statistical analysis over 150 independence runs to find the fitness value. 展开更多
关键词 ANN Archimedes optimization water cycle algorithm stretching/shrinking surface convergent/divergent channel
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A Strategy Toward Convergent Combination Immunotherapy for SARS
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作者 Wayne A. Marasco 《中国实验动物学报》 CAS CSCD 2005年第S1期12-,共1页
关键词 A Strategy Toward convergent Combination Immunotherapy for SARS
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Missile guidance law design based on free-time convergent error dynamics
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作者 LIU Yuanhe XIE Nianhao +1 位作者 LI Kebo LIANG Yan’gang 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1315-1325,共11页
To solve the finite-time error-tracking problem in mis-sile guidance,this paper presents a unified design approach through error dynamics and free-time convergence theory.The proposed approach is initiated by establis... To solve the finite-time error-tracking problem in mis-sile guidance,this paper presents a unified design approach through error dynamics and free-time convergence theory.The proposed approach is initiated by establishing a desired model for free-time convergent error dynamics,characterized by its independence from initial conditions and guidance parameters,and adjustable convergence time.This foundation facilitates the derivation of specific guidance laws that integrate constraints such as leading angle,impact angle,and impact time.The theoretical framework of this study elucidates the nuances and synergies between the proposed guidance laws and existing methodologies.Empirical evaluations through simulation comparisons underscore the enhanced accuracy and adaptability of the proposed laws. 展开更多
关键词 guidance design free-time convergence error dynamics approach impact angle constraint impact time constraint
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A Class of Parallel Algorithm for Solving Low-rank Tensor Completion
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作者 LIU Tingyan WEN Ruiping 《应用数学》 北大核心 2025年第4期1134-1144,共11页
In this paper,we established a class of parallel algorithm for solving low-rank tensor completion problem.The main idea is that N singular value decompositions are implemented in N different processors for each slice ... In this paper,we established a class of parallel algorithm for solving low-rank tensor completion problem.The main idea is that N singular value decompositions are implemented in N different processors for each slice matrix under unfold operator,and then the fold operator is used to form the next iteration tensor such that the computing time can be decreased.In theory,we analyze the global convergence of the algorithm.In numerical experiment,the simulation data and real image inpainting are carried out.Experiment results show the parallel algorithm outperform its original algorithm in CPU times under the same precision. 展开更多
关键词 Tensor completion Low-rank CONVERGENCE Parallel algorithm
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Smoluchowski-Kramers Approximation for Stochastic Differential Equations under Discretization
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作者 Li Ge 《应用概率统计》 北大核心 2025年第4期622-635,共14页
This paper studies the Smoluchowski–Kramers approximation for a discrete-time dynamical system modeled as the motion of a particle in a force field.We show that the approximation holds for the drift-implicit Euler–M... This paper studies the Smoluchowski–Kramers approximation for a discrete-time dynamical system modeled as the motion of a particle in a force field.We show that the approximation holds for the drift-implicit Euler–Maruyama discretization and derive its convergence rate.In particular,the solution of the discretized system converges to the solution of the first-order limit equation in the mean-square sense,and this convergence is independent of the order in which the mass parameterμand the step size h tend to zero. 展开更多
关键词 stochastic differential equations Smoluchowski-Kramers approximation driftimplicit Euler-Maruyama scheme convergence rate
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A Modified PRP-HS Hybrid Conjugate Gradient Algorithm for Solving Unconstrained Optimization Problems
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作者 LI Xiangli WANG Zhiling LI Binglan 《应用数学》 北大核心 2025年第2期553-564,共12页
In this paper,we propose a three-term conjugate gradient method for solving unconstrained optimization problems based on the Hestenes-Stiefel(HS)conjugate gradient method and Polak-Ribiere-Polyak(PRP)conjugate gradien... In this paper,we propose a three-term conjugate gradient method for solving unconstrained optimization problems based on the Hestenes-Stiefel(HS)conjugate gradient method and Polak-Ribiere-Polyak(PRP)conjugate gradient method.Under the condition of standard Wolfe line search,the proposed search direction is the descent direction.For general nonlinear functions,the method is globally convergent.Finally,numerical results show that the proposed method is efficient. 展开更多
关键词 Conjugate gradient method Unconstrained optimization Sufficient descent condition Global convergence
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Fixed-time Target-guided Coordinate Control of Unmanned Surface Vehicles Based on Dynamic Surface Control
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作者 LI Chao−yi XU Hai−xiang +2 位作者 YU Wen−zhao DU Zhe DING Ya−nan 《船舶力学》 北大核心 2025年第6期849-862,共14页
This paper presents an investigation on the target-guided coordinated control(TACC)of unmanned surface vehicles(USVs).In the scenario of tracking non-cooperative targets,the status information of the target can only b... This paper presents an investigation on the target-guided coordinated control(TACC)of unmanned surface vehicles(USVs).In the scenario of tracking non-cooperative targets,the status information of the target can only be obtained by some USVs.In order to achieve semi-encirclement tracking of noncooperative targets under maritime security conditions,a fixed-time tracking control method based on dynamic surface control(DSC)is proposed in this paper.Firstly,a novel TACC architecture with decoupled kinematic control law and decoupled kinetic control law was designed to reduce the complexity of control system design.Secondly,the proposed DSC-based target-guided kinematic control law including tracking points pre-allocation strategy and sigmoid artificial potential functions(SigAPFs)can avoid collisions during tracking process and optimize kinematic control output.Finally,a fixed-time TACC system was proposed to achieve fast convergence of kinematic and kinetics errors.The effectiveness of the proposed TACC approach in improving target tracking safety and reducing control output chattering was verified by simulation comparison results. 展开更多
关键词 unmanned surface vehicle distributed control target-guided coordinate control fixed-time convergence dynamic surface control
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A New Technique for Constructing Higher-order Iterative Methods to Solve Nonlinear Systems
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作者 XIAO Xiaoyong 《应用数学》 北大核心 2025年第3期762-774,共13页
In this paper,a new technique is introduced to construct higher-order iterative methods for solving nonlinear systems.The order of convergence of some iterative methods can be improved by three at the cost of introduc... In this paper,a new technique is introduced to construct higher-order iterative methods for solving nonlinear systems.The order of convergence of some iterative methods can be improved by three at the cost of introducing only one additional evaluation of the function in each step.Furthermore,some new efficient methods with a higher-order of convergence are obtained by using only a single matrix inversion in each iteration.Analyses of convergence properties and computational efficiency of these new methods are made and testified by several numerical problems.By comparison,the new schemes are more efficient than the corresponding existing ones,particularly for large problem sizes. 展开更多
关键词 Systems of nonlinear equation Order of convergence Higher-order method Extended Newton iteration Computational efficiency
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Equivalent Conditions of Complete Convergence for Weighted Sums of Sequences of i.i.d.Random Variables under Sublinear Expectations
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作者 XU Mingzhou CHENG Kun 《应用概率统计》 北大核心 2025年第3期339-352,共14页
The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the... The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the equivalent conditions of complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space.The results complement the corresponding results in probability space to those for sequences of independent,identically distributed random variables under sublinear expectation space. 展开更多
关键词 complete convergence weighted sums i.i.d.random variables sublinear expectation
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Complete f-Moment Convergence for Sung’s Type Weighted Sums of Negatively Superadditive Dependent Random Variables
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作者 HU Xueping WANG Liuliu +1 位作者 HU Ke XU Zhonghao 《应用概率统计》 北大核心 2025年第4期585-601,共17页
In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergen... In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergence of NSD random variables.We establish and improve a general result on the complete f-moment convergence for Sung’s type randomly weighted sums of NSD random variables under some general assumptions.As an application,we show the complete consistency for the randomly weighted estimator in a nonparametric regression model based on NSD errors. 展开更多
关键词 Marcinkiewicz-Zygmund inequality Rosenthal-type inequality Sung’s type randomly weighted sums negatively superadditive dependent random variables complete f-moment convergence
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An improved genetic algorithm for causal discovery
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作者 MAO Tengjiao BU Xianjin +2 位作者 CAI Chunxiao LU Yue DU Jing 《Journal of Systems Engineering and Electronics》 2025年第3期768-777,共10页
The learning algorithms of causal discovery mainly include score-based methods and genetic algorithms(GA).The score-based algorithms are prone to searching space explosion.Classical GA is slow to converge,and prone to... The learning algorithms of causal discovery mainly include score-based methods and genetic algorithms(GA).The score-based algorithms are prone to searching space explosion.Classical GA is slow to converge,and prone to falling into local optima.To address these issues,an improved GA with domain knowledge(IGADK)is proposed.Firstly,domain knowledge is incorporated into the learning process of causality to construct a new fitness function.Secondly,a dynamical mutation operator is introduced in the algorithm to accelerate the convergence rate.Finally,an experiment is conducted on simulation data,which compares the classical GA with IGADK with domain knowledge of varying accuracy.The IGADK can greatly reduce the number of iterations,populations,and samples required for learning,which illustrates the efficiency and effectiveness of the proposed algorithm. 展开更多
关键词 genetic algorithm(GA) causal discovery convergence rate fitness function mutation operator
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深海会聚区波导不变量特征研究及应用 被引量:4
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作者 唐帅 笪良龙 +1 位作者 徐国军 崔宝龙 《海洋科学》 CAS CSCD 北大核心 2014年第7期82-88,共7页
为了解决深海会聚区目标及其运动态势难以判断的问题,在研究会聚区形成条件和其声场传播规律以及波导不变量理论的基础上,对典型深海环境不同位置的声强距离-频率分布图中的干涉条纹特征进行理论分析和仿真验证。结果表明,深海会聚区存... 为了解决深海会聚区目标及其运动态势难以判断的问题,在研究会聚区形成条件和其声场传播规律以及波导不变量理论的基础上,对典型深海环境不同位置的声强距离-频率分布图中的干涉条纹特征进行理论分析和仿真验证。结果表明,深海会聚区存在与其他区域不同的干涉条纹特征,其对应的波导不变量?值为负。本文提出了利用会聚区特有的干涉条纹特征,对会聚区目标及其运动态势进行初步判断的方法,仿真结果和试验数据表明,判断方法具有可行性和有效性。 展开更多
关键词 波导不变量 会聚区 目标运动态势 CONVERGENCE ZONE (CZ)
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新闻传播学中Convergence一词溯源及内涵 被引量:192
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作者 宋昭勋 《现代传播(中国传媒大学学报)》 CSSCI 北大核心 2006年第1期51-53,共3页
Convergence是当今新闻传播学中最重要同时又语意模糊的概念。本文通过追溯该词在新闻传播学中的历史演进,阐释了不同传播语境下该词所表达的6种不同涵义:媒体科技融合(ConvergenceinMediaTechnology)、媒体所有权合并(ConvergenceofOwn... Convergence是当今新闻传播学中最重要同时又语意模糊的概念。本文通过追溯该词在新闻传播学中的历史演进,阐释了不同传播语境下该词所表达的6种不同涵义:媒体科技融合(ConvergenceinMediaTechnology)、媒体所有权合并(ConvergenceofOwnership)、媒体战术性联合(ConvergenceofMediaTactics)、媒体组织结构性融合(StructuralConvergenceofMediaOrganization)、新闻采访技能融合(ConvergenceofinformationGathering)和新闻叙事形式融合(ConvergenceofNewsStorytelling),并简介了媒体融合对新闻传播业界及学界的影响。 展开更多
关键词 CONVERGENCE 媒体融合 新闻传播学
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Three-dimensional impact angle constrained distributed cooperative guidance law for anti-ship missiles 被引量:10
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作者 LI Wei WEN Qiuqiu +1 位作者 HE Lei XIA Qunli 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第2期447-459,共13页
This paper investigates the problem of distributed cooperative guidance law design for multiple anti-ship missiles in the three-dimensional(3-D)space hitting simultaneously the same target with considering the desired... This paper investigates the problem of distributed cooperative guidance law design for multiple anti-ship missiles in the three-dimensional(3-D)space hitting simultaneously the same target with considering the desired terminal impact angle constraint.To address this issue,the problem formulation including 3-D nonlinear mathematical model description,and communication topology are built firstly.Then the consensus variable is constructed using the available information and can reach consensus under the proposed acceleration command along the line-of-sight(LOS)which satisfies the impact time constraint.However,the normal accelerations are designed to guarantee the convergence of the LOS angular rate.Furthermore,consider the terminal impact angle constraints,a nonsingular terminal sliding mode(NTSM)control is introduced,and a finite time convergent control law of normal acceleration is proposed.The convergence of the proposed guidance law is proved by using the second Lyapunov stability method,and numerical simulations are also conducted to verify its effectiveness.The results indicate that the proposed cooperative guidance law can regulate the impact time error and impact angle error in finite time if the connecting time of the communication topology is longer than the required convergent time. 展开更多
关键词 distributed cooperative guidance law impact angle constraint communication topology nonsingular terminal sliding mode(NTSM)control finite time convergent
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大传媒时代文学的跨媒介传播现象研究 被引量:6
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作者 孔朝蓬 《学习与探索》 CSSCI 北大核心 2015年第12期133-136,共4页
现代数字化技术的高度发展与媒介融合时代的来临,使文学的媒介环境发生了巨大变化,随之引起文学创作、文学传播与文学接受的整体性改变。在大传媒时代媒介融合背景下文学传播的多元化、个性化与全球化成为文学与媒介文化研究的重要命题... 现代数字化技术的高度发展与媒介融合时代的来临,使文学的媒介环境发生了巨大变化,随之引起文学创作、文学传播与文学接受的整体性改变。在大传媒时代媒介融合背景下文学传播的多元化、个性化与全球化成为文学与媒介文化研究的重要命题。以文学、传播学、影视艺术学等交叉视角和综合探索为前提,具体分析传播环境变迁与文学的发展、媒介融合与文学发展空间的拓展、媒介融合与文学跨媒介传播的表现形态,引发了对大传媒时代文学的多样化生存、适应性改变等问题的深度思考。 展开更多
关键词 大传媒时代 媒介融合(Media Convergence) 文学 跨媒介传播
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基于混沌遗传算法的圆度误差测量 被引量:2
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作者 王伯平 王薇 +3 位作者 孙大刚 阎献国 都丽娜 Bo-ping Da-gang Xian-guo Li-na 《计量学报》 CSCD 北大核心 2009年第6期-,共3页
提出了一种基于混沌遗传算法的计算圆度误差的新方法.它利用混沌优化方法的遍历性和随机性,通过混沌扰动操作可克服传统遗传算法中的早熟问题,确保算法的全局收敛性.该方法满足最小条件原理,其计算结果的精确度非常高,理论上可以获得全... 提出了一种基于混沌遗传算法的计算圆度误差的新方法.它利用混沌优化方法的遍历性和随机性,通过混沌扰动操作可克服传统遗传算法中的早熟问题,确保算法的全局收敛性.该方法满足最小条件原理,其计算结果的精确度非常高,理论上可以获得全局最优解.实例计算表明,这种算法简单明确,具有精度高、收敛速度快、易于计算机程序实现和推广应用等特点. Abstract: A new method for calculating the roundness error based on chaos genetic algorithms is proposed. The system utilizes the ergodicity and randomness of chaos optimal method and by means of chaos stir operation, which can overcame the problem of premature convergence in traditional genetic algorithms and ensured an convergence of the algorithms. The method satisfies the principle of the least condition, the precision of calculating result is very high and can find .the global optimal solution. An actual calculated example showed that this method is simple and clear and it has features of high precision and fast convergent speed as well as using computer easily and popularizing application easily. 展开更多
关键词 混沌遗传算法 圆度误差测量 GENETIC ALGORITHMS Based ROUNDNESS ERROR GENETIC ALGORITHMS premature convergence 计算结果 ROUNDNESS ERROR high precision 混沌优化方法 传统遗传算法 traditional application 全局最优解 全局收敛性 new method operation 最小条件 推广应用
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Collaborative beamforming based on directional perturbation using one bit feedback 被引量:2
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作者 Haifen Yang Ning Ding +3 位作者 Zhi Zheng Shuisheng Lin Zhongpei Zhang Guangjun Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第3期549-554,共6页
A novel collaborative beamforming algorithm is proposed in a wireless communication system with multiple transmitters and one receiver. All transmitters take part in the collaboration and the weighted message is trans... A novel collaborative beamforming algorithm is proposed in a wireless communication system with multiple transmitters and one receiver. All transmitters take part in the collaboration and the weighted message is transmitted simultaneously. In order to maximize the beamforming gain, the transmitters use one bit feedback information to adjust the phase offset. It tracks the direction in which the signal strength at the receiver can increase. The directional search and perturbation theory is used to achieve the phase alignment. The feasibility of the proposed algorithm is proved both experimentally and theoretically. Simulation results show that the proposed algorithm can improve the convergent speed of the phase alignment. 展开更多
关键词 collaborative beamforming one-bit feedback directional perturbation convergent speed
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基于Converge的柴油机起动过程喷雾撞壁仿真分析
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作者 李华兵 马宁 +1 位作者 左红稳 傅振宇 《科学技术与工程》 北大核心 2020年第34期14060-14066,共7页
柴油机起动过程中,转速、缸内背景压力及温度偏低会导致喷雾撞壁,影响燃油雾化效果。利用三维计算软件Converge,采用组合喷雾模型及Bai-Gosman(B-G)撞壁模型建立了燃油喷雾撞壁模型,并利用可视化定容弹喷雾撞壁试验系统验证了模型的准... 柴油机起动过程中,转速、缸内背景压力及温度偏低会导致喷雾撞壁,影响燃油雾化效果。利用三维计算软件Converge,采用组合喷雾模型及Bai-Gosman(B-G)撞壁模型建立了燃油喷雾撞壁模型,并利用可视化定容弹喷雾撞壁试验系统验证了模型的准确性。基于建立的喷雾撞壁模型,研究分析了缸内背景压力、壁面干湿状况及壁面粗糙度对某型柴油机喷雾撞壁的影响规律。仿真结果表明:随着缸内背景压力下降,撞壁时刻提前,扩散距离增大,油膜产生时刻提前,油膜厚度增大;活塞顶壁面粗糙度增加,喷雾油束撞壁后扩散距离减小,附壁油膜厚度增大;当活塞顶壁面为湿壁时,喷雾油束撞壁后扩散距离增大,附壁油膜厚度下降。研究为燃烧室、喷油系统等优化设计提供了参考。 展开更多
关键词 柴油机 Converge 喷雾撞壁 仿真
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压力对柴油/生物柴油混合燃料喷雾特性影响数值模拟 被引量:1
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作者 叶丽华 刘雯靖 薛定邦 《农业装备与车辆工程》 2023年第7期13-17,共5页
环境污染及能源短缺对当前动力机械的应用提出更高要求,研究替代燃料是一种有效途径。基于CONVERGE软件搭建了定容弹喷雾计算模型,研究柴油/生物柴油混合燃料在不同工况下的喷雾燃烧特性,为其在发动机中的实际应用提供一定的理论依据。... 环境污染及能源短缺对当前动力机械的应用提出更高要求,研究替代燃料是一种有效途径。基于CONVERGE软件搭建了定容弹喷雾计算模型,研究柴油/生物柴油混合燃料在不同工况下的喷雾燃烧特性,为其在发动机中的实际应用提供一定的理论依据。模拟计算了体积比20%生物柴油和柴油混合燃料的喷雾特性,根据仿真结果,分析了混合燃料在喷射压力120~150 MPa,背压3.0~5.0 MPa变化下,喷雾贯穿距、索特平均直径(SMD)、速度变化的分布情况。仿真计算结果表明,混合燃料的喷雾贯穿距随着喷射压力的增大而增大、SMD减小、喷雾中心速度增大,增大喷射压力可以改善雾化;随着背压升高,喷雾贯穿距减小、SMD略微增大、喷雾中心区域速度降低,背压增加增大了气液之间作用力,不利于燃料雾化。 展开更多
关键词 CONVERGE 喷雾特性 SMD 喷雾贯穿距 速度场
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CARBONATITES FROM THE EASTERN HIMALAYAN SYNTAXIS: PETROLOGY AND TECTONIC IMPLICATIONS
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作者 Liu Yan 1, Zhong Dalai 2, Ji Jianqing 3(1 Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China 2 Institute of Geology & Geophysics, Chinese Academy of Sciences, Beijing 100029, China 3 Department of Geology, Pek 《地学前缘》 EI CAS CSCD 2000年第S1期10-11,共2页
Most carbonatites occur in relatively stable, intra\|plate areas but some are found to occur in near to plate margins and may be linked with plate separation (Woolley, 1989). Although many carbonatites have been disco... Most carbonatites occur in relatively stable, intra\|plate areas but some are found to occur in near to plate margins and may be linked with plate separation (Woolley, 1989). Although many carbonatites have been discovered to occur in the orogenic belts in recent years, most of these rocks are related to post\|orogenic magmatism, that is, the rocks occur in the specially extensional setting. Therefore it is unusual that such magmatic rocks occur in the typical convergent environment. Here we report carbonatites and associated ultramafic and mafic rocks in the core of the eastern Himalayan syntaxis. The eastern Himalayan syntaxis consists of three tectonic units: the Gangdise, the Yarlung Zangbo, and the Himalayan units, each of which is bounded by faults (Liu & Zhong, 1997). The Himalayan unit, the northernmost exposed part of the Indian plate, is divided into two complexes, the amphibolite facies complex in the south and the granulite facies complex in the north. The granulite facies complex in the Himalayan unit have been argued to experience high\|pressure metamorphism and represent materials buried to upper\|mantle depths (Liu & Zhong, 1997). The carbonatites and associated ultramafic and mafic rocks only occur in the granulite facies rocks and are divided into two belts: northern and southern belts.The northern belt extends at least 30km, and is about 20km in width. The southern belt extends several kilometers, and is 3km or so in width. Each belt consists mainly of differently compositional dykes, extending parallel to gneissosity of granulite facies gneiss. Carbonatitic agglomerates are observed in the northern belt. From the center of carbonatite dykes to country rocks, five types of rock are observed: the center parts of carbonatites, the rim parts of carbonatites, ultramafic and mafic rocks, altered rocks and country rocks. The gneissosity of country rock was deformed by intrusion of dykes. 展开更多
关键词 Eastern HIMALAYAN Syntaxis CARBONATITES ULTRAMAFIC rocks carbonatitie MAGMATISM convergent environment
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