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A new expansion method of first order nonlinear ordinary differential equation with at most a sixth-degree nonlinear term and its application to mBBM model 被引量:3
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作者 潘军廷 龚伦训 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第2期399-402,共4页
Based on a first order nonlinear ordinary differential equation with at most a sixth-degree nonlinear term which is extended from a type of elliptic equation, and by converting it into a new expansion form, this paper... Based on a first order nonlinear ordinary differential equation with at most a sixth-degree nonlinear term which is extended from a type of elliptic equation, and by converting it into a new expansion form, this paper proposes a new algebraic method to construct exact solutions for nonlinear evolution equations. Being concise and straightforward, the method is applied to modified Benjamin-Bona-Mahony (mBBM) model, and some new exact solutions to the system are obtained. The algorithm is of important significance in exploring exact solutions for other nonlinear evolution equations. 展开更多
关键词 nonlinear evolution equations new expansion method mBBM model exact solutions
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New Method of Total Ionizing Dose Compact Modeling in Partially Depleted Silicon-on-Insulator MOSFETs 被引量:4
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作者 黄建强 何伟伟 +3 位作者 陈静 罗杰馨 吕凯 柴展 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第9期82-85,共4页
On the basis of a detailed discussion of the development of total ionizing dose (TID) effect model, a new commercial-model-independent TID modeling approach for partially depleted silicon-on-insulator metal-oxide- s... On the basis of a detailed discussion of the development of total ionizing dose (TID) effect model, a new commercial-model-independent TID modeling approach for partially depleted silicon-on-insulator metal-oxide- semiconductor field effect transistors is developed. An exponential approximation is proposed to simplify the trap charge calculation. Irradiation experiments with 60Co gamma rays for IO and core devices are performed to validate the simulation results. An excellent agreement of measurement with the simulation results is observed. 展开更多
关键词 of new method of Total Ionizing Dose Compact modeling in Partially Depleted Silicon-on-Insulator MOSFETs for SOI TID in is IO NMOS on
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Establishment of a new method of digital orthopedic surgery and its widespread clinical application
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作者 丁焕文 《外科研究与新技术》 2011年第2期126-127,共2页
Objective To create an unique new method of digital orthopedic surgery and widely apply to spinal surgery,treatment of bone and joint injuries,ligament reconstruction and repair,bone minor resection and reconstruction... Objective To create an unique new method of digital orthopedic surgery and widely apply to spinal surgery,treatment of bone and joint injuries,ligament reconstruction and repair,bone minor resection and reconstruction,serious bone and 展开更多
关键词 establishment of a new method of digital orthopedic surgery and its widespread clinical application
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Solutions to Teaching Reform Challenges of Elective Courses under the Background of New Liberal Arts:Taking International Trade in Services Course as an Example
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作者 Huiqian Yu 《Journal of Contemporary Educational Research》 2024年第11期28-33,共6页
Variations in the allocation of university resources,teachers’course selection preferences and teaching commitment levels,as well as students’course preferences and assessment requirements,create subjective differen... Variations in the allocation of university resources,teachers’course selection preferences and teaching commitment levels,as well as students’course preferences and assessment requirements,create subjective differences.These differences,compounded by the demands of the new liberal arts reform,place significant challenges and pressure on elective course instructors.To meet these demands,elective course teachers should enhance their teaching methods and explore new instructional models.The International Trade in Services course,for instance,has implemented six areas of curriculum reform,enriching the practice of elective course improvement. 展开更多
关键词 new liberal arts reform Elective course Curriculum teaching model Teaching method reform Curriculum test
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Penalty model for delay of bidding section construction period in South-to-North Water Diversion Eastern Route Project from perspective of programs 被引量:2
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作者 Jing-chun FENG Ya-fang REN +2 位作者 Zhong-nan DUAN Zhan-jun LIU Hai-yang LI 《Water Science and Engineering》 EI CAS 2012年第3期350-360,共11页
According to the multi-project and program management theory, this paper analyzes the program generation principle and establishes a program based on progress goals. On the basis of the present situation of calculatio... According to the multi-project and program management theory, this paper analyzes the program generation principle and establishes a program based on progress goals. On the basis of the present situation of calculation of penalty for delay of the bidding section construction period with the critical path method, we studied the effects of contractor-induced delay of the bidding section construction period in detail, including the effects on the construction period of the bidding section itself, the earliest start times of the next bidding section and other subsequent bidding sections, and the construction period of the program, and then constructed a penalty model for delay of the bidding section construction period from the perspective of programs. Using the penalty model, we conducted a practical analysis of penalty for delay of the construction period of the Baoying station program in the South-to-North Water Diversion Project. The model can help determine the amount of penalty for delay of the construction period in bidding sections scientifically and reasonably, 展开更多
关键词 program establishment program management bidding section construction period critical path method (CPM) penaly model South-to-North Water Diversion Project
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Numerical Solution of Model of Cancer Invasion with Tissue
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作者 Farhad Hatami Mohammad Bagher Ghaemi 《Applied Mathematics》 2013年第7期1050-1058,共9页
Chemotaxis-haptotaxis model of cancer invasion with tissue remodeling is one of the important PDE’s systems in medicine, mathematics and biomathematics. In this paper we find the solution of chemotaxis-haptotaxis mod... Chemotaxis-haptotaxis model of cancer invasion with tissue remodeling is one of the important PDE’s systems in medicine, mathematics and biomathematics. In this paper we find the solution of chemotaxis-haptotaxis model of cancer invasion using the new homotopy perturbation method (NHPM). Then by comparing some estimated numerical result with simulation laboratory result, it shows that NHPM is an efficient and exact way for solving cancer PDE’s system. 展开更多
关键词 CHEMOTaXIS HaPTOTaXIS model of Cancer INVaSION new HOMOTOPY PERTURBaTION method
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A New Differential Operator Method to Study the Mechanical Vibration
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作者 Quansheng Ji Xiaomei Ji +1 位作者 Linhong Ji Yuxi Zheng 《Modern Mechanical Engineering》 2012年第3期65-70,共6页
In this paper, we propose a unified differential operator method to study mechanical vibrations, solving inhomogeneous linear ordinary differential equations with constant coefficients. The main advantage of this new ... In this paper, we propose a unified differential operator method to study mechanical vibrations, solving inhomogeneous linear ordinary differential equations with constant coefficients. The main advantage of this new method is that the differential operator D in the numerator of the fraction has no effect on input functions (i.e., the derivative operation is removed) because we take the fraction as a whole part in the partial fraction expansion. The method in various variants is widely implemented in related fields in mechanics and engineering. We also point out that the same mistakes in the differential operator method are found in the related references [1-4]. 展开更多
关键词 new DIFFERENTIaL Operator method Mechanical VIBRaTION (Torsional VIBRaTION of Rolling-Mill) Torque amplification Factor model analysis method LaPLaCE Transform
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A Theoretical Model of pH-Based Potentiometric Biosensor Based on Immobilized Enzyme Membrane
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作者 Jeganathan Saranya Lakshmanan Rajendran Mariappan Uma Maheswari 《American Journal of Analytical Chemistry》 2016年第4期363-377,共15页
A theoretical model for the non steady-state response of a pH-based potentiometric biosensor immobilizing organophosphorus hydrolase (OPH) is discussed. The model is based on a system of five coupled nonlinear reactio... A theoretical model for the non steady-state response of a pH-based potentiometric biosensor immobilizing organophosphorus hydrolase (OPH) is discussed. The model is based on a system of five coupled nonlinear reaction-diffusion equations under non steady-state conditions for enzyme reactions occurring in potentiometric biosensor that describes the concentration of substrate and hydrolysis products within the membrane. New approximate analytical expressions for the concentration of the substrate (organophosphorus pesticides (OPs)) and products are derived for all values of Thiele modulus and buffer concentration using new approach of homotopy perturbation method. The analytical results are also compared with numerical ones and a good agreement is obtained. The obtained results are valid for the whole solution domain. 展开更多
关键词 Mathematical modeling REaCTION-DIFFUSION pH-Based Potentiometric Biosensor asymptotic methods new Homotopy Perturbation method
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Deformation and failure mechanism of slope in three dimensions 被引量:20
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作者 Yingfa Lu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第2期109-119,共11页
Understanding three-dimensional (3D) slope deformation and failure mechanism and corresponding stability analyses are crucially important issues in geotechnical engineering. In this paper, the mecha-nisms of progressi... Understanding three-dimensional (3D) slope deformation and failure mechanism and corresponding stability analyses are crucially important issues in geotechnical engineering. In this paper, the mecha-nisms of progressive failure with thrust-type and pull-type landslides are described in detail. It is considered that the post-failure stress state and the pre-peak stress state may occur at different regions of a landslide body with deformation development, and a critical stress state element (or the soil slice block) exists between the post-failure stress state and the pre-peak stress state regions. In this regard, two sorts of failure modes are suggested for the thrust-type and three sorts for pull-type landslides, based on the characteristics of shear stress and strain (or tensile stress and strain). Accordingly, a new joint constitutive model (JCM) is proposed based on the current stability analytical theories, and it can be used to describe the mechanical behaviors of geo-materials with softening properties. Five methods, i.e. CSRM (comprehensive sliding resistance method), MTM (main thrust method), CDM (comprehensive displacement method), SDM (surplus displacement method), and MPM (main pull method), for slope stability calculation are proposed. The S-shaped curve of monitored displacement vs. time is presented for different points on the sliding surface during progressive failure process of landslide, and the rela-tionship between the displacement of different points on the sliding surface and height of landslide body is regarded as the parabolic curve. The comparisons between the predicted and observed loadedis-placement and displacementetime relations of the points on the sliding surface are conducted. The classification of stable/unstable displacementetime curves is proposed. The definition of the main sliding direction of a landslide is also suggested in such a way that the failure body of landslide (simplified as“collapse body”) is only involved in the main sliding direction, and the strike and the dip are the same as the collapse body. The rake angle is taken as the direction of the sum of sliding forces or the sum of displacements in collapse body, in which the main slip direction is dependent on progressive defor-mation. The reason of non-convergence with finite element method (FEM) in calculating the stability of slope is also numerically analyzed, in which a new method considering the slip surface associated with the boundary condition is proposed. It is known that the boundary condition of sliding surface can be described by perfect elasto-plastic model (PEPM) and JCM, and that the stress and strain of a landslide can be described properly with the JCM. 展开更多
关键词 Failure mechanism new joint constitutive model(JCM) Stability analyses Boundary method by sliding surface
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Adiabatic correction for the esterification of acetic anhydride by methanol via accurate kinetics
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作者 Ze Dong Liping Chen +2 位作者 Yingying Ma Haoliang Peng Wanghua Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第9期1954-1959,共6页
In the field of adiabatic correction for complex reactions,a simple one-stage kinetic model was used to estimate the real reaction kinetics.However,this assumption simplified the real process,inevitably generated inac... In the field of adiabatic correction for complex reactions,a simple one-stage kinetic model was used to estimate the real reaction kinetics.However,this assumption simplified the real process,inevitably generated inaccurate or even unsafe results.Therefore,it was necessary to find a new correction method for complex reactions.In this work,esterification of acetic anhydride by methanol was chosen as an object reaction of study.The reaction was studied under different conditions by Reaction Calorimeter(RC1).Then,Thermal Safety Software(TSS)was used to establish the kinetic model and estimate the parameters,where,activation energies for three stages were67.09,81.02,73.77 kJ?mol^(-1)respectively,and corresponding frequency factors in logarithmic form were 16.05,19.59,15.72 s^(-1).In addition,two adiabatic tests were performed by Vent Sizing Package2(VSP2).For accurate correction of VSP2 tests,a new correction method based on Enhanced Fisher method was proposed.Combined with kinetics,adiabatic correction of esterification reaction was achieved.Through this research,accurate kinetic parameters for a three-step kinetic model of the esterification reaction were acquired.Furthermore,the correlation coefficients between simulated curves and corrected curves were 0.976 and 0.968,which proved the accuracy of proposed new adiabatic correction method.Based on this new method,conservative corrected results were able to be acquired and be applied in safety assessment. 展开更多
关键词 adiabatic correction KINETICS new method Complex reaction ESTERIFICaTION model reaction
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Extended Jacobian Elliptic Function Expansion Method and Its Applications in Biology
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作者 Emad H. M. Zahran Mostafa M. A. Khater 《Applied Mathematics》 2015年第7期1174-1181,共8页
In this work, an extended Jacobian elliptic function expansion method is proposed for constructing the exact solutions of nonlinear evolution equations. The validity and reliability of the method are tested by its app... In this work, an extended Jacobian elliptic function expansion method is proposed for constructing the exact solutions of nonlinear evolution equations. The validity and reliability of the method are tested by its applications to Dynamical system in a new Double-Chain Model of DNA and a diffusive predator-prey system which play an important role in biology. 展开更多
关键词 Extended JaCOBIaN Elliptic Function Expansion method Dynamical SYSTEM in a new DOUBLE-CHaIN model of DNa a Diffusive PREDaTOR-PREY SYSTEM Traveling WaVE SOLUTIONS Solitary WaVE SOLUTIONS
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Theoretical Analysis of Immobilized Oxidase Enzyme Electrode in the Presence of Two Oxidants
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作者 Malinidevi Ramanathan Rajendran Lakshmanan 《American Journal of Analytical Chemistry》 2016年第10期679-695,共17页
In this paper, mathematical model of Martens and Hall (Analytical chemistry 66, 2763-2770 (1994)) for an immobilized oxidase enzyme electrode is discussed. The model involves the system of non-linear reaction diffusio... In this paper, mathematical model of Martens and Hall (Analytical chemistry 66, 2763-2770 (1994)) for an immobilized oxidase enzyme electrode is discussed. The model involves the system of non-linear reaction diffusion equations under the steady state conditions. A simple and closed-form of approximate analytical expressions for the concentrations of the immobilization of three enzyme substrates has been derived by solving the system of non-linear reaction diffusion equations using new approach of homotopy perturbation method. Approximate polynomial expression of concentration of substrate, oxygen and oxidized mediator and current was obtained in terms of the Thiele moduli and the small values of parameters B<sub>s</sub>, B<sub>o</sub> and B<sub>m</sub> (normalized surface concentration of substrate, oxygen and oxidized mediator). Furthermore, in this work the numerical simulation of the problem is also reported using Matlab program. An agreement between analytical expressions and numerical results is noted. 展开更多
关键词 Mathematical modelling Enzyme Electrodes Non-linear Reaction Diffusion Equation new Homotopy Perturbation method
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基于AHP与熵值法构建的火灾预测组合灰色模型
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作者 郑子温 那孜古力·斯拉木 +1 位作者 王婧蓉 王旭东 《现代电子技术》 北大核心 2024年第5期118-126,共9页
火灾预测可以帮助消防部门更好地采取预防措施和制定灭火方案,减轻火灾损失。如何通过人工智能方法预测火灾数量、判断火灾发展趋势成为一项重要的研究课题。对城市消防火灾数量进行预测时,文中首先对原始数据序列进行加权滑动均值处理... 火灾预测可以帮助消防部门更好地采取预防措施和制定灭火方案,减轻火灾损失。如何通过人工智能方法预测火灾数量、判断火灾发展趋势成为一项重要的研究课题。对城市消防火灾数量进行预测时,文中首先对原始数据序列进行加权滑动均值处理;其次建立了基于背景值优化的灰色模型和无偏优化灰色模型;而后引入了结合等维新息理论的马尔可夫模型,对经过改进的灰色模型进行预测值的残差修正;最后建立了基于层次分析法(AHP)与熵值法的主客观赋权组合模型。针对北京市2012—2019年火灾事故数据进行建模,并对后续两年的火灾发生数量进行数据预测与模型对比验证分析,根据预测结果判断未来火灾数据的变化趋势。实验结果显示,优化模型可以提高预测精度,其中结合AHP与熵值法的组合模型预测精度达到了相对残差最小为0.6105%,后验方差比为0.323%。实验结果证明,优化后的模型可以更好地应用于对火灾事故的预测。 展开更多
关键词 火灾事故预测 GM(1 1) 马尔可夫模型 等维新息理论 层次分析法 熵值法 组合模型预测
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基于AI大模型技术的新能源发电功率预测优化方法及系统
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作者 袁振邦 《中国高新科技》 2024年第16期85-87,共3页
文章就AI大模型技术的新能源发电功率预测优化方法及系统进行探讨,结合AI大模型的核心技术及特点,分析了AI大模型预测优化的方法及预测优化系统,旨在能为新能源发电的发展提供重要的理论支撑和科学依据。结果表明,优化后AI大模型技术的... 文章就AI大模型技术的新能源发电功率预测优化方法及系统进行探讨,结合AI大模型的核心技术及特点,分析了AI大模型预测优化的方法及预测优化系统,旨在能为新能源发电的发展提供重要的理论支撑和科学依据。结果表明,优化后AI大模型技术的新能源方法,解决了传统预测手段难以全面捕捉和解析气象因素与发电效能之间复杂且多变的互动问题,为电网的稳定运行和高效管理提供了依据。 展开更多
关键词 aI大模型 新能源发电功率 预测优化 方法 系统
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我国采矿CAD开发存在的问题与对策 被引量:8
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作者 邵安林 孙豁然 +1 位作者 刘晓军 李世明 《金属矿山》 CAS 北大核心 2004年第2期1-4,19,共5页
分析了当前国内外采矿CAD的应用现状 ,回顾了 2 0世纪 90年代以来国内采矿CAD的研究过程 ,总结了国内采矿CAD开发的经验 ,指出我国采矿CAD存在的主要问题是作坊式的开发、模拟手工设计、缺乏高新算法和三维模型的支持等 ,认为进行矿床... 分析了当前国内外采矿CAD的应用现状 ,回顾了 2 0世纪 90年代以来国内采矿CAD的研究过程 ,总结了国内采矿CAD开发的经验 ,指出我国采矿CAD存在的主要问题是作坊式的开发、模拟手工设计、缺乏高新算法和三维模型的支持等 ,认为进行矿床三维实体模型的研究与在此基础上开发采矿CAD将是我国采矿CAD的发展方向。 展开更多
关键词 采矿CaD 高新算法 三维实体模型 矿业软件
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“立德树人”理念下公共管理类本科专业课程教学质量评价指标体系研究——基于CIPP-AHP的分析 被引量:6
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作者 郭涵 杨国永 郑永平 《未来与发展》 2023年第7期45-53,共9页
从“立德树人”理念视角,借鉴现有研究成果,基于CIPP模型拟定公共管理类本科课程教学质量评价指标框架,结合德尔菲法遴选具体评价指标,并运用层次分析法(AHP)确定指标权重,最终构建出公共管理类本科课程教学质量评价指标体系。研究认为... 从“立德树人”理念视角,借鉴现有研究成果,基于CIPP模型拟定公共管理类本科课程教学质量评价指标框架,结合德尔菲法遴选具体评价指标,并运用层次分析法(AHP)确定指标权重,最终构建出公共管理类本科课程教学质量评价指标体系。研究认为:过程性评价在公共管理类课程质量评价中具有重要作用;教学理念和教学内容是课程教学质量提升的关键因素;评价指标设置应体现“立德树人”教育理念和公共管理学科建设的时代要求。 展开更多
关键词 立德树人 公共管理类 指标体系 CIPP模型:aHP法
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新能源产业的金融支持绩效评价——基于DEA和Logit模型 被引量:14
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作者 徐枫 周文浩 《科技管理研究》 CSSCI 北大核心 2014年第20期33-38,共6页
金融支持在产业发展中扮演着不可或缺的角色。新能源产业作为国家七大战略性新兴产业之一,依赖现有的金融支持渠道却呈现出供过于求的产能过剩现象。实现资源优化配置,解决产能过剩现象,恰当的金融支持渠道是关键。通过数据包络分析和... 金融支持在产业发展中扮演着不可或缺的角色。新能源产业作为国家七大战略性新兴产业之一,依赖现有的金融支持渠道却呈现出供过于求的产能过剩现象。实现资源优化配置,解决产能过剩现象,恰当的金融支持渠道是关键。通过数据包络分析和逻辑模型,对沪深股市的新能源产业代表品种进行金融支持效率的实证分析,根据回归结果得出具体金融支持渠道的有效性以及相关程度,从而给出相应的政策建议。 展开更多
关键词 新能源 金融支持 绩效评价 DEa分析 逻辑模型
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CO/Air称量法制备的不确定度评估 被引量:3
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作者 李春瑛 吴海 韩桥 《低温与特气》 CAS 2015年第1期26-34,共9页
介绍了称量法制备CO/Air不确定度的评定过程;对称量数学模型的建立、称量过程、原料气体纯度分析及不确定度的评估方法进行了阐述;给出了CCQM-K84 CO/Air大气背景浓度的国际关键比对实验结果。
关键词 CO/air气体标准物质 称量法 数学模型的建立 不确定度的评定
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优化的Gray Markov模型在埋地管道腐蚀速率预测中的应用 被引量:15
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作者 骆正山 陈晨 王哲 《腐蚀与防护》 CAS 北大核心 2019年第5期313-317,326,共6页
为提高埋地管道剩余寿命预测的精确度,对传统灰色马尔科夫预测模型进行优化。将管道腐蚀速率视为一个灰色系统,对灰色模型的原始数据光滑处理后建立等维新信息无偏灰色模型,预测腐蚀速率的宏观值。以优化的灰色模型预测值残差为基础结... 为提高埋地管道剩余寿命预测的精确度,对传统灰色马尔科夫预测模型进行优化。将管道腐蚀速率视为一个灰色系统,对灰色模型的原始数据光滑处理后建立等维新信息无偏灰色模型,预测腐蚀速率的宏观值。以优化的灰色模型预测值残差为基础结合马尔科夫链模型,进行二次平滑处理和白化系数寻优,得出残差修正值。最终,结合两种优化模型得出管道腐蚀速率的预测值。实例检验证明,该模型能有效克服系统长期动态预测上的不足,与传统灰色马尔科夫链预测模型相比,预测精度提高了40. 33%,预测结果与实测值有更高的拟合程度。 展开更多
关键词 无偏新信息灰色模型 马尔科夫模型 二次平滑指数法 粒子群算法 管道腐蚀速率预测
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基于ADAMS的新一代水下生产系统功能舱深水悬垂下放仿真研究 被引量:2
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作者 贾晓丽 郭永豪 +1 位作者 刘书海 王懿 《石油科学通报》 2019年第2期174-183,共10页
悬垂下放法(Pendulous Installation Method,简称PIM)是针对超深水环境和较大重量管汇的安装专门设计的一种快捷、简便的安装方法,更适用于新一代水下生产系统.本文基于多体动力学软件ADAMS对功能舱的下放过程进行仿真,将功能舱简化为... 悬垂下放法(Pendulous Installation Method,简称PIM)是针对超深水环境和较大重量管汇的安装专门设计的一种快捷、简便的安装方法,更适用于新一代水下生产系统.本文基于多体动力学软件ADAMS对功能舱的下放过程进行仿真,将功能舱简化为球体加圆柱体的组合体形式,以多段小圆柱体加轴套力的形式近似模拟缆索,参考Morison公式进行绕流阻力的计算,建立了悬垂下放多刚体动力学仿真模型.通过与其他参考文献结果对比验证了模型的有效性.讨论了流体速度、功能舱重力和缆索长度等对下放过程的影响.本文研究内容可对新一代水下生产系统功能舱的工程应用提供理论指导. 展开更多
关键词 新一代水下生产系统 悬垂下放 功能舱 aDaMS 多刚体动力学仿真模型
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