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A novel lattice model integrating the cooperative deviation of density and optimal flux under V2X environment
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作者 彭光含 罗春莉 +1 位作者 赵红专 谭惠丽 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期626-633,共8页
A novel lattice hydrodynamic model is proposed by integrating the cooperative deviation of density and optimal flux under vehicle to X(V2X) environment. According to the theoretical analysis, the stability conditions ... A novel lattice hydrodynamic model is proposed by integrating the cooperative deviation of density and optimal flux under vehicle to X(V2X) environment. According to the theoretical analysis, the stability conditions and the mKdV equations affected by the cooperative deviation of traffic information are explored. And the density wave, hysteresis loop and energy consumption of the traffic flow have been investigated via numerical simulation. The results indicate that the cooperative deviation of density and optimal flux can effectively alleviate the traffic congestion. More importantly, our new consideration can reduce fuel consumption and exhaust emission under the V2X environment. 展开更多
关键词 traffic flow lattice hydrodynamic model cooperative deviation
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Efficient Deviation Detection Between a Process Model and Event Logs 被引量:4
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作者 Lu Wang Yuyue Du Liang Qi 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第6期1352-1364,共13页
Business processes described by formal or semi-formal models are realized via information systems.Event logs generated from these systems are probably not consistent with the existing models due to insufficient design... Business processes described by formal or semi-formal models are realized via information systems.Event logs generated from these systems are probably not consistent with the existing models due to insufficient design of the information system or the system upgrade.By comparing an existing process model with event logs,we can detect inconsistencies called deviations,verify and extend the business process model,and accordingly improve the business process.In this paper,some abnormal activities in business processes are formally defined based on Petri nets.An efficient approach to detect deviations between the process model and event logs is proposed.Then,business process models are revised when abnormal activities exist.A clinical process in a healthcare information system is used as a case study to illustrate our work.Experimental results show the effectiveness and efficiency of the proposed approach. 展开更多
关键词 DETECT deviationS event LOG model repair PETRI net process model
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MODERATE DEVIATIONS FROM HYDRODYNAMIC LIMIT OF A GINZBURG-LANDAU MODEL 被引量:2
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作者 王霞 高付清 《Acta Mathematica Scientia》 SCIE CSCD 2006年第4期691-701,共11页
The authors consider the moderate deviations of hydrodynamic limit for Ginzburg-Landau models. The moderate deviation principle of hydrodynamic limit for a specific Ginzburg-Landau model is obtained and an explicit fo... The authors consider the moderate deviations of hydrodynamic limit for Ginzburg-Landau models. The moderate deviation principle of hydrodynamic limit for a specific Ginzburg-Landau model is obtained and an explicit formula of the rate function is derived. 展开更多
关键词 Hydrodynamic limit large deviations moderate deviations Ginzburg-Landau model
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Large Deviations for Random Sums on Some Kind of Heavy-tailed Classes in Risk Models 被引量:3
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作者 KONG Fan-chao WANG Jin-liang 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第1期71-79,共9页
This paper is a further investigation into the large deviations for random sums of heavy-tailed,we extended and improved some results in ref. [1] and [2]. These results can applied to some questions in Insurance and F... This paper is a further investigation into the large deviations for random sums of heavy-tailed,we extended and improved some results in ref. [1] and [2]. These results can applied to some questions in Insurance and Finance. 展开更多
关键词 renewal risk model heavy-tailed distribution large deviation renewal counting process
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Effect of Froude similitude deviation on curved channel simulations: A case study in the Middle Yangtze River
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作者 Xiao-ting Yang Qian-qian Shang +3 位作者 Hui Xu Guo-bin Li Ya-jun Gao Qi-lin Yang 《Water Science and Engineering》 EI CAS CSCD 2023年第3期289-294,共6页
Froude similitude and friction similitude are the two crucial similarity conditions that are often used in physical-scale modeling of rivers.However,models often deviate from Froude similitude when dealing with real-w... Froude similitude and friction similitude are the two crucial similarity conditions that are often used in physical-scale modeling of rivers.However,models often deviate from Froude similitude when dealing with real-world situations.This study developed several fixed-bed river models with various curvatures to determine the effect of Froude similitude deviation on curved channel modeling.Models were constructed according to the characteristics of the Middle Yangtze River.Differences in longitudinal slope,transverse slope,and main stream line location were measured by varying Froude similitude deviation.The deviations of longitudinal slope and velocity were negligible because friction similitude was accounted for.The transverse slope varied significantly with the Froude similitude deviation,and the main stream line varied with the curvature and Froude similitude deviation.Formulae were derived to estimate the slope deviation.These analyses helped to clarify the feasibility of the method of Froude similitude deviation for curved channels. 展开更多
关键词 Fixed-bed river model Froude similitude deviation Flow movement Water surface slope Middle Yangtze river
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Precise large deviations for sums of random vectors in a multidimensional size-dependent renewal risk model 被引量:1
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作者 SHEN Xin-mei FU Ke-ang ZHONG Xue-ting 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2018年第4期491-502,共12页
Consider a multidimensional renewal risk model, in which the claim sizes {Xk, k ≥1} form a sequence of independent and identically distributed random vectors with nonnegative components that are allowed to be depende... Consider a multidimensional renewal risk model, in which the claim sizes {Xk, k ≥1} form a sequence of independent and identically distributed random vectors with nonnegative components that are allowed to be dependent on each other. The univariate marginal distributions of these vectors have consistently varying tails and finite means. Suppose that the claim sizes and inter-arrival times correspondingly form a sequence of independent and identically distributed random pairs, with each pair obeying a dependence structure. A precise large deviation for the multidimensional renewal risk model is obtained. 展开更多
关键词 Precise large deviation SIZE-DEPENDENT Consistent variation Multidimensional risk model Renewal counting process
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Mechanism Modeling and Simulation Based on Dimensional Deviation
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作者 王亚斌 刘明杰 谭惠民 《Journal of Beijing Institute of Technology》 EI CAS 2008年第4期419-422,共4页
To analyze the effects on motion characteristics of mechanisms of dimensional variations, a study on random dimensional deviation generation techniques for 3D models on the basis of the present mechanical modeling sof... To analyze the effects on motion characteristics of mechanisms of dimensional variations, a study on random dimensional deviation generation techniques for 3D models on the basis of the present mechanical modeling software was carried out, which utilized the redeveloped interfaces provided by the modeling software to develop a random dimensional deviation generation system with certain probability distribution characteristics. This system has been used to perform modeling and simulation of the specific mechanical time delayed mechanism under multiple deviation varieties, simulation results indicate the dynamic characteristics of the mechanism are influenced significantly by the dimensional deviation in the tolerance distribution range, which should be emphasized in the design. 展开更多
关键词 dimensional deviation modelING SIMULATION mechanical time delayed mechanism
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Deviation Diagnosis and Analysis of Hull Flat Block Assembly Based on a State Space Model
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作者 Zhiying Zhang Yinfang Dai Zhen Li 《Journal of Marine Science and Application》 2012年第3期311-320,共10页
Dimensional control is one of the most important challenges in the shipbuilding industry. In order to predict assembly dimensional variation in hull flat block construction, a variation stream model based on state spa... Dimensional control is one of the most important challenges in the shipbuilding industry. In order to predict assembly dimensional variation in hull flat block construction, a variation stream model based on state space was presented in this paper which can be further applied to accuracy control in shipbuilding. Part accumulative error, locating error, and welding deformation were taken into consideration in this model, and variation propagation mechanisms and the accumulative rule in the assembly process were analyzed. Then, a model was developed to describe the variation propagation throughout the assembly process. Finally, an example of fiat block construction from an actual shipyard was given. The result shows that this method is effective and useful. 展开更多
关键词 hull fiat block state space model deviation source diagnosis
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Solving the Problem of Silicon Dioxide Melting Based on Deviation Model
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作者 Yuhan Sun Na Huang Jie Yu 《Non-Metallic Material Science》 2020年第1期1-5,共5页
In order to reveal the dissolution behavior of iron tailings in blast furnace slag,we studied the main component of silica in iron tailings.First,edge contour features need to be established to represent the melting p... In order to reveal the dissolution behavior of iron tailings in blast furnace slag,we studied the main component of silica in iron tailings.First,edge contour features need to be established to represent the melting process of silica.We choose shape,perimeter,area and generalized radius as objects.By independently analyzing the influence of these four indexes on the melting rate,the area and shape were selected as the characteristic parameters of the edge contour of the silica particles.Then,the actual melting rate of the silica is estimated by the edge contour feature index.Finally,we can calculate the melting rate of the first second of three time periods of 0.00010312mm^3/s,0.0002399mm^3/s,0.0000538mm^3/s. 展开更多
关键词 IMAGE SUPERPOSITION deviation model INTERPOLATION test
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Precise large deviation result for heavy-tailed random sums and applications to risk theory
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作者 杨洋 林金官 《Journal of Southeast University(English Edition)》 EI CAS 2010年第3期498-501,共4页
The differences between two sequences of nonnegative independent and identically distributed random variables with sub-exponential tails and the random index are studied. The random index is a strictly stationary rene... The differences between two sequences of nonnegative independent and identically distributed random variables with sub-exponential tails and the random index are studied. The random index is a strictly stationary renewal counting process generated by some negatively associated random variables. Using a revised large deviation result of partial sums, the elementary renewal theorem and the central limit theorem of negatively associated random variables, a precise large deviation result is derived for the random sums. The result is applied to the customer-arrival-based insurance risk model. Some uniform asymptotics for the ruin probabilities of an insurance company are obtained as the number of customers or the time tends to infinity. 展开更多
关键词 precise large deviation random sum sub-exponential distribution renewal counting process customer-arrival-based insurance risk model
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An improved deviation model for transonic stages in axial compressors
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作者 Xiaochen WANG Xuesong LI +3 位作者 Xiaodong REN Chunwei GU Xiaobin QUE Guoyu ZHOU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第7期93-108,共16页
Deviation model is an important model for through-flow analysis in axial compressors.Theoretical analysis in classical deviation models is developed under the assumption of onedimensional flow,which is controlled by t... Deviation model is an important model for through-flow analysis in axial compressors.Theoretical analysis in classical deviation models is developed under the assumption of onedimensional flow,which is controlled by the continuity equation.To consider three-dimensional characteristics in transonic flow,this study proposes an improved theoretical analysis method combining force analysis of the blade-to-blade flow with conventional analysis of the continuity equation.Influences of shock structures on transverse force,streamwise velocity and streamline curvature in the blade-to-blade flow are analyzed,and support the analytical modelling of density flow ratio between inlet and outlet conditions.Thus,a novel deviation model for transonic stages in axial compressors is proposed in this paper.The empirical coefficients are corrected based on the experimental data of a linear cascade,and the prediction accuracy is validated with the experimental data of a three-stage transonic compressor.The novel model provides accurate predictions for meridional flow fields at the design point and performance curves at design speed,and shows obvious improvements on classical models by Carter and C¸etin. 展开更多
关键词 Axial compressor Transonic flow deviation model Through-flow method Aerodynamic performance
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Numerical simulation analysis for deformation deviation and experimental verification for an antenna thin-wall parts considering riveting assembly with finite element method 被引量:6
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作者 PAN Ming-hui TANG Wen-cheng +1 位作者 XING Yan NI Jun 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第1期60-77,共18页
In the process of thin-wall parts assembly for an antenna,the parts assembly deformation deviation is occurring due to the riveting assembly.In view of the riveting assembly deformation problems,it can be analyzed thr... In the process of thin-wall parts assembly for an antenna,the parts assembly deformation deviation is occurring due to the riveting assembly.In view of the riveting assembly deformation problems,it can be analyzed through transient and static simulation.In this work,the theoretical deformation model for riveting assembly is established with round head rivet.The simulation analysis for riveting deformation is carried out with the riveting assembly piece including four rivets,which comparing with the measuring points experiment results of riveting test piece through dealing with the experimental data using the point coordinate transform method and the space line fitting method.Simultaneously,the deformation deviation of the overall thin-wall parts assembly structure is analyzed through finite element simulation;and its results are verified by the measuring experiment for riveting assembly with the deformation deviation of some key points on the thin-wall parts.Through the comparison analysis,it is shown that the simulation results agree well with the experimental results,which proves the correctness and effectiveness of the theoretical analysis,simulation results and the given experiment data processing method.Through the study on the riveting assembly for thin-wall parts,it will provide a theoretical foundation for improving thin-wall parts assembly quality of large antenna in future. 展开更多
关键词 thin-wall parts assembly assembly deformation deviation theoretical deformation model finite element simulation measuring experiment
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Several problems about strain calculation and analysis and correction of related deviation 被引量:2
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作者 Yang Guohua Wu Yanqiang +3 位作者 Yang Bo Zhan Wei Zhang Fengshuang Han Yueping 《Geodesy and Geodynamics》 2011年第1期29-35,共7页
There exists many kinds of calculation models of plane and spherical strain fields, but the results of these models are different. The representative models was analyzed, and got some useful conclusions, in which some... There exists many kinds of calculation models of plane and spherical strain fields, but the results of these models are different. The representative models was analyzed, and got some useful conclusions, in which some models are unbiased, some have deviations that can be corrected, some can only be used to compute strain in a uniform medium and can not be extended, and some can be used in the calculation and analysis of continuous strain field as well. Meanwhile, the correction relationship for spherical difference movement (displacement) computed from strain results was given, and the meaning of the non - differential term in spherical strain model was demonstrated. 展开更多
关键词 GNSS horizontal strain calculation model applicability deviation correction conversion relationship strain filtering
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Nasal airflow of patient with septal deviation and allergy rhinitis 被引量:1
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作者 Zi Fen Lim Parvathy Rajendran +1 位作者 Muhamad Yusri Musa Chih Fang Lee 《Visual Computing for Industry,Biomedicine,and Art》 EI 2021年第1期120-130,共11页
A numerical simulation of a patient’s nasal airflow was developed via computational fluid dynamics.Accordingly,computerized tomography scans of a patient with septal deviation and allergic rhinitis were obtained.The ... A numerical simulation of a patient’s nasal airflow was developed via computational fluid dynamics.Accordingly,computerized tomography scans of a patient with septal deviation and allergic rhinitis were obtained.The three-dimensional(3D)nasal model was designed using InVesalius 3.0,which was then imported to(computer aided 3D interactive application)CATIA V5 for modification,and finally to analysis system(ANSYS)flow oriented logistics upgrade for enterprise networks(FLUENT)to obtain the numerical solution.The velocity contours of the cross-sectional area were analyzed on four main surfaces:the vestibule,nasal valve,middle turbinate,and nasopharynx.The pressure and velocity characteristics were assessed at both laminar and turbulent mass flow rates for both the standardized and the patient’s model nasal cavity.The developed model of the patient is approximately half the size of the standardized model;hence,its velocity was approximately two times more than that of the standardized model. 展开更多
关键词 Three-dimensional nasal airflow model Septal deviation Allergy rhinitis Computational fluid dynamics
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Comprehensive Evaluation on the Agricultural Sustainable Development with the Smallest Generalized Deviation
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作者 LAN Tian-yi Basis Department,Xijing University,Xi’an 710123,China 《Asian Agricultural Research》 2011年第4期15-17,共3页
Evaluation index system of agricultural sustainable development is constructed with the four components of social index,agricultural economic index,resources index,and environment index.According to the comprehensive ... Evaluation index system of agricultural sustainable development is constructed with the four components of social index,agricultural economic index,resources index,and environment index.According to the comprehensive evaluation model of agricultural sustainable development with the participation of single person,comprehensive evaluation model of agricultural sustainable development with the smallest generalized deviation and the participation of many people is established.Based on the case studies,agricultural sustainable development status of a certain region is evaluated.Result shows that the evaluation scores of the social index and agricultural economic index are high in this region,but the score of resources index is general and the evaluation result of environment index is not very good.The comprehensive evaluation value of overall sustainable development is 0.665 5;and the evaluation result is "good". 展开更多
关键词 model with the smallest GENERALIZED deviation Sust
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Applications of Mogulskii, and Kurtz-Feng Large Deviation Results to Risk Reserve Processes with Aggregate Claims
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作者 Jorge Garcia Ana Meda 《Applied Mathematics》 2012年第12期2109-2117,共9页
In this paper we examine the large deviations principle (LDP) for sequences of classic Cramér-Lundberg risk processes under suitable time and scale modifications, and also for a wide class of claim distributions ... In this paper we examine the large deviations principle (LDP) for sequences of classic Cramér-Lundberg risk processes under suitable time and scale modifications, and also for a wide class of claim distributions including (the non-super- exponential) exponential claims. We prove two large deviations principles: first, we obtain the LDP for risk processes on D∈[0,1] with the Skorohod topology. In this case, we provide an explicit form for the rate function, in which the safety loading condition appears naturally. The second theorem allows us to obtain the LDP for Aggregate Claims processes on D∈[0,∞) with a different time-scale modification. As an application of the first result we estimate the ruin probability, and for the second result we work explicit calculations for the case of exponential claims. 展开更多
关键词 Large deviations Cramer-Lundberg Reserve Risk PROCESSES Probability Theory and Mathematical Statistics in INSURANCE Stochastic models for CLAIM Frequency CLAIM Size and Aggregate CLAIMS RESERVES
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Exit problem of stochastic SIR model with limited medical resource
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作者 Y.C.Mao X.B.Liu 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2023年第1期8-13,共6页
Nonlinearity and randomness are both the essential attributes for the real world,and the case is the same for the models of infectious diseases,for which the deterministic models can not give a complete picture of the... Nonlinearity and randomness are both the essential attributes for the real world,and the case is the same for the models of infectious diseases,for which the deterministic models can not give a complete picture of the evolution.However,although there has been a lot of work on stochastic epidemic models,most of them focus mainly on qualitative properties,which makes us somewhat ignore the original meaning of the parameter value.In this paper we extend the classic susceptible-infectious-removed(SIR)epidemic model by adding a white noise excitation and then we utilize the large deviation theory to quantitatively study the long-term coexistence exit problem with epidemic.Finally,in order to extend the meaning of parameters in the corresponding deterministic system,we tentatively introduce two new thresholds which then prove rational. 展开更多
关键词 Stochastic epidemic model Stochastic dynamical system Large deviation theory Exit problem
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顾及城市发展和生态保护均衡的宜昌市生境质量多情景模拟研究 被引量:1
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作者 李明 胡封举 +3 位作者 包丹 于婧 张又天 陈朝霞 《湖北大学学报(自然科学版)》 CAS 2024年第3期320-329,共10页
城市发展过程中不同的发展方向与生态保护目标往往会产生不同的矛盾冲突,通过均衡城市发展和生态保护之间的关系,能够促进城市发展和生态保护的耦合协调。以宜昌市为研究对象,耦合PLUS—InVEST模型并结合标准差椭圆分析,以2020年土地利... 城市发展过程中不同的发展方向与生态保护目标往往会产生不同的矛盾冲突,通过均衡城市发展和生态保护之间的关系,能够促进城市发展和生态保护的耦合协调。以宜昌市为研究对象,耦合PLUS—InVEST模型并结合标准差椭圆分析,以2020年土地利用现状数据为基础,模拟自然发展、经济发展以及生态保护3种情景下2040年宜昌市生境质量变化情况。研究结果表明:1)2000—2020年宜昌市主要发生变化的地类为耕地、林地以及建设用地,其中林地与耕地为主要的转出地类,建设用地为主要的转入地类;2)在不同模拟情景下,建设用地扩张方向均由西南向东北收缩,城市扩张强度减缓,建设用地扩张强度重心并开始由东向西进行迁徙;3)在自然发展和经济发展情景下,宜昌市生境质量在未来均呈现衰退的趋势,而在生态保护情景下,宜昌市生境质量有所恢复。通过模拟未来不同政策下土地利用方式改变来反映宜昌市生境质量变化情况,为均衡城市发展与生态保护产生的矛盾和冲突有着重要意义。 展开更多
关键词 生境质量 PLUS模型 InVEST模型 标准差椭圆分析 宜昌市
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基于频率匹配的EC模式定量降水偏差订正 被引量:2
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作者 周威 魏庆 +1 位作者 杨康权 陈茂强 《气象水文海洋仪器》 2024年第3期22-25,共4页
为了提升模式预报效果,文章利用四川盆地南部20182020年59月的EC模式降水预报资料和实况降水资料,采用频率匹配的方法对EC模式的24 h累计降水进行订正、分析和检验。结果表明当降水阈值小于25.0 mm时,EC模式定量降水预报存在明显湿偏差... 为了提升模式预报效果,文章利用四川盆地南部20182020年59月的EC模式降水预报资料和实况降水资料,采用频率匹配的方法对EC模式的24 h累计降水进行订正、分析和检验。结果表明当降水阈值小于25.0 mm时,EC模式定量降水预报存在明显湿偏差,反之存在弱干偏差。研究结果为提升相关区域的降水预报能力提供支持。 展开更多
关键词 EC模式 降水 频率匹配 偏差订正
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基于灰色模型的装配式建筑施工偏差预测研究
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作者 阮雪琴 章晴雯 刘海霞 《科技资讯》 2024年第13期114-116,共3页
利用灰色预测模型GM(1,1)对装配式建筑施工偏差进行了分析和预测,选择预制板的平面度偏差数据作为研究对象,通过数据的预处理、模型的建立、模型参数的估计、模型的求解、模型的还原和模型的检验等步骤,得到了预测值与实测值的对比图,... 利用灰色预测模型GM(1,1)对装配式建筑施工偏差进行了分析和预测,选择预制板的平面度偏差数据作为研究对象,通过数据的预处理、模型的建立、模型参数的估计、模型的求解、模型的还原和模型的检验等步骤,得到了预测值与实测值的对比图,以及预测误差和后验差比等指标,评价了模型的预测精度和适用性。结果表明:模型能够反映出预制板的平面度偏差的变化规律,后验差比小于模型的预测精度,可应用于装配式建筑施工中。 展开更多
关键词 灰色预测模型 装配式建筑 施工偏差 平面度
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