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基于v-gap达到L_(2)最优的EIV模型频域辨识方法研究
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作者 萧德云 耿立辉 +5 位作者 纪国锋 张益农 农时猛 杨帆 巨辉 刘敏华 《控制理论与应用》 北大核心 2025年第11期2156-2164,共9页
本文论述一类基于v-gap测度、达到实现L_(2)最优的变量带误差(EIV)模型辨识问题,包括单输入单输出系统的开环与闭环EIV模型辨识和多输入多输出系统的EIV模型辨识.基于v-gap测度就是以扰动模型与逼近模型之间的距离为优化准则,当满足相应... 本文论述一类基于v-gap测度、达到实现L_(2)最优的变量带误差(EIV)模型辨识问题,包括单输入单输出系统的开环与闭环EIV模型辨识和多输入多输出系统的EIV模型辨识.基于v-gap测度就是以扰动模型与逼近模型之间的距离为优化准则,当满足相应的Nyquist缠绕条件时,获得模型辨识的最优解.达到L_(2)最优是指,在L_(2)空间下对扰动的输出和输入频域实验数据进行正交分解,使正规右互质因子描述的系统模型的值空间与系统模型补因子描述的噪声模型的值空间具有正交性,通过优化v-gap测度间接使逼近误差(噪声)达到L_(2)最小.本文所提出的方法为EIV模型辨识提供了一种新的研究途径,同时适用于闭环系统和多变量系统等多种情况下,不需要对系统输入和输出有界噪声的特性做任何假设,可以同时估计获得系统模型和相应的噪声模型,在工程上具有广泛的实用性. 展开更多
关键词 系统辨识 EIV模型 v-gap测度 L_(2)最优准则 频域
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Using Huntingtin Knock-In Minipigs to Fill the Gap Between Mouse Models and Patients with Huntington's Disease
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作者 Xiangqian Liu Ting Peng He Li 《Neuroscience Bulletin》 SCIE CAS CSCD 2018年第5期870-872,共3页
Huntington's disease (HD) is an inherited autosomal dominant neurodegenerative disease characterized by pro- gressive motor deficits, cognitive decline, and psychiatric symptoms. It is caused by a pathological expa... Huntington's disease (HD) is an inherited autosomal dominant neurodegenerative disease characterized by pro- gressive motor deficits, cognitive decline, and psychiatric symptoms. It is caused by a pathological expansion of CAG trinucleotide repeats in exon 1 of the HD gene, resulting in the translation of a mutant form of huntingtin protein (mutant Htt) with an expanded polyglutamine domain in the N-terminal region [1 ]. Despite great progress in understanding the pathogenesis of HD using multiple mouse models, the exact mechanisms by which mutant Htt induces neuronal dysfunction and death are still not completely clear, and there is no curative treatment for this disease. An important reason is that the mouse, which is the most widely used animal model in HD research, differs from the human in many aspects, including the physiology, drug metabolism, blood-brain barrier, life span, brain volume, and neuroanatomical organization [2]. Thus, it is necessary to establish HD models with higher species than rodents, such as the dog, pig, and non- human primate, so as to bridge the gap between preclinical mouse models and clinical studies. 展开更多
关键词 HD In Using Huntingtin Knock-In Minipigs to Fill the gap Between Mouse models and Patients with Huntington’s Disease
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The Additive-multiplicative Hazards Model for Multiple Type of Recurrent Gap Times
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作者 Zhang Qi-xian Liu Ji-cai +1 位作者 Guan Qiang Wang De-hui 《Communications in Mathematical Research》 CSCD 2015年第2期97-107,共11页
Recurrent event gap times data frequently arise in biomedical studies and often more than one type of event is of interest. To evaluate the effects of covariates on the marginal recurrent event hazards functions, ther... Recurrent event gap times data frequently arise in biomedical studies and often more than one type of event is of interest. To evaluate the effects of covariates on the marginal recurrent event hazards functions, there exist two types of hazards models: the multiplicative hazards model and the additive hazards model. In the paper, we propose a more flexible additive-multiplicative hazards model for multiple type of recurrent gap times data, wherein some covariates are assumed to be additive while others are multiplicative. An estimating equation approach is presented to estimate the regression parameters. We establish asymptotic properties of the proposed estimators. 展开更多
关键词 additive-multiplicative hazards model estimating equation gap time multiple recurrent event data semi-parametric regression model
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Using Test Employee Capability Maturity Model for Supporting Gaps Bridging in Software Testing 被引量:1
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作者 Jithinan Sirathienchai Peraphon Sophatsathit Decha Dechawatanapaisal 《Journal of Software Engineering and Applications》 2012年第6期417-428,共12页
This study addresses the challenge of assessing gaps among the differences of test people in eight groups by matching them based on four scenarios. The proposed model called Test Employee Capability Maturity Model (TE... This study addresses the challenge of assessing gaps among the differences of test people in eight groups by matching them based on four scenarios. The proposed model called Test Employee Capability Maturity Model (TEC-MM) helps find the gaps and measure the capability and maturity levels of each sub-maturity models in four dimensions as technicality, management, business, and personality. We applied TEC-MM to a software company which has instituted test people improvement strategy and plans to be a front runner in software testing industry. The findings reveal that gaps existed and consequently affect software testing process quality. 展开更多
关键词 Software Testing TEST People CAPABILITY MATURITY model CAPABILITY and MATURITY Levels gap Assessment
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Bridging Strategies for Non-contact Cognitive Dissonance Among College Students During University Lockdown in China:An Analytical Framework Based on the Quality Gap Model
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作者 WU Mei DONG Yuting 《Psychology Research》 2024年第4期148-159,共12页
Research has found that the“non-contact”cognitive dissonance is an increasingly common phenomenon among college students during the COVID-19 pandemic lockdown of a university in China.For this,a qualitative approach... Research has found that the“non-contact”cognitive dissonance is an increasingly common phenomenon among college students during the COVID-19 pandemic lockdown of a university in China.For this,a qualitative approach based on psychological literature,and the“Quality Gap Model”in marketing are adopted,and a“non-contact”cognitive dissonance model of college students has been constructed.According to the model,cognitive dissonance is caused by the gap between college students’individual behavior and the expectation for the“non-contact”policy,the gap between college students’expectation with the university and the reality,and the gap between the expectation for the policy provider and the perceived reality.The research further explains the psychological mechanism of this behavior.It is proposed that the impact bias“catalyzes”the“escalation”of the“non-contact”cognitive dissonance behavior among college students.To solve this problem,the gap should be filled considering the following three aspects:counter attitudinal advocacy,establishment of cognitive overlap,and cognitive transformation.The unique contribution of the present study is presentation of a new perspective on“non-contact”cognitive dissonance based on public behavior management and to provide a case of controlling and prevention from the pandemic COVID-19 in China. 展开更多
关键词 Quality gap model public crisis online public opinion policy pressure impact bias post-decision disorder
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The AMSAA-BISE Model with Gap Intervals 被引量:1
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作者 Zhou Yuanquan and Weng Zhaoxi(Beijing Institute of Structure and Environment) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1990年第1期77-83,共7页
In this paper, the AMSAA-BISE model with missing data is discussed. The ML estimates of model parameters and current MTBF are given, and the chi-squared test and a plot for cumulative number of failures versus cumulat... In this paper, the AMSAA-BISE model with missing data is discussed. The ML estimates of model parameters and current MTBF are given, and the chi-squared test and a plot for cumulative number of failures versus cumulative testing time are used to test the goodness of fit for the model. This paper concludes with a numerical example to verify the model. 展开更多
关键词 Reliability growth gap interval Missing data AMSAA-BISE model.
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Dynamic development model for long gap discharge streamer-leader system based on fractal theory 被引量:2
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作者 Jianghai GENG Quansheng WANG +3 位作者 Xiaomin LIU Ping WANG Fangcheng LYU Yujian DING 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第9期68-76,共9页
Establishing a long air gap discharge model considering the streamer-leader transition and randomness of the discharge path is of great signiflcance to improve the accuracy of discharge characteristic prediction and o... Establishing a long air gap discharge model considering the streamer-leader transition and randomness of the discharge path is of great signiflcance to improve the accuracy of discharge characteristic prediction and optimize external insulation design.Based on fractal theory and thermal ionization theory of streamer-leader transition,this work establishes a dynamic development model for the long air gap discharge streamer-leader system,which includes streamer inception,streamer development,leader inception,development of streamer-leader system and flnal jump.The positive discharge process of a 3 m rod plate is simulated to obtain the fractal distribution of the discharge path and the law of leader development for comparison with the discharge test results.The results show that the simulation model is similar to test results in the development characteristics of leader path distribution,each stage time and leader velocity.Finally,a simulation calculation of a 50%breakdown voltage of the rod-plate gap and ball-plate gap is carried out,with results fairly consistent with test data,proving the effectiveness and practicality of the model. 展开更多
关键词 long air gap fractal theory thermal ionization streamer-leader system simulation model
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Study on Stack Effect of Stairwell by Numerical Model of Leakage Flow through Gap of Door
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作者 Jung-Yup Kim Ji-Seok Kim 《Open Journal of Fluid Dynamics》 2013年第4期241-247,共7页
Since stack effect that occurs in high-rise buildings has an effect on the indoor environment of the buildings, energy loss and smoke control in case of a fire, there is a need to conduct research on this. For an anal... Since stack effect that occurs in high-rise buildings has an effect on the indoor environment of the buildings, energy loss and smoke control in case of a fire, there is a need to conduct research on this. For an analysis of the stack effect, analysis methods on the leakage flow through gap of interior door shall be formulated. Until now, studies related to the gap leakage flow in buildings have mainly analyzed flow field and pressure in the buildings one-dimensionally using pressure difference-leakage flowrate relations of Orifice Equation and a network numerical analysis algorithm that as- sumes each compartment in the buildings as a single point. In this study, the Momentum Loss Model which enables pressure drop to be proportional to the flow velocity through the gap of door in computational domain of 3-dimensional numerical analysis was proposed to reflect the gap flow phenomenon effectively in 3-dimensional numerical analysis. Using the proposed model, 3-dimensional numerical analysis of the stack effect on the stairs in buildings was performed, and the effects of separation door and lobby between stair and accommodation on the stack effect were investigated. 展开更多
关键词 STACK Effect LEAKAGE Flow gap of DOOR MOMENTUM Loss model Separation DOOR NUMERICAL Analysis
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A Study on the Factors Influencing the Income Gap between Urban and Rural Areas Based on State-space Model 被引量:2
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作者 Xiaofang ZOU Xueqin JIANG 《Asian Agricultural Research》 2014年第9期1-6,共6页
The increasingly widening income gap between urban and rural areas is affected by many factors. Using the stepwise regression analysis,we find that urbanization level,socio-economic development,education level,financi... The increasingly widening income gap between urban and rural areas is affected by many factors. Using the stepwise regression analysis,we find that urbanization level,socio-economic development,education level,financial development scale and financial development efficiency have the greatest impact on the income gap between urban and rural areas. By cointegration test,it is found that there is a long-term equilibrium relationship between these five variables and the income gap between urban and rural areas. We build the state-space model to research the dynamic impact of these factors on the income gap between urban and rural areas. The results show that by improving the level of urbanization,we can effectively narrow the income gap between urban and rural areas,while socio-economic development,the improvement of education level,expansion of financial development scale and financial development efficiency all significantly expand the income gap between urban and rural areas. 展开更多
关键词 INCOME gap BETWEEN URBAN and RURAL areas State-spa
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林隙(Gap)模型研究进展 被引量:27
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作者 于振良 赵士洞 《生态学杂志》 CAS CSCD 北大核心 1997年第2期42-46,共5页
林隙(Gap)模型研究进展于振良赵士洞(中国科学院自然资源综合考察委员会,北京100101)AdvancesofGapModel.YuZhenliang,ZhaoShidong(CommisionforIntegra... 林隙(Gap)模型研究进展于振良赵士洞(中国科学院自然资源综合考察委员会,北京100101)AdvancesofGapModel.YuZhenliang,ZhaoShidong(CommisionforIntegratedSurveyofNatura... 展开更多
关键词 森林生态学 森林群落 林隙模型
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基于info-gap理论的结构非概率可靠性方法研究 被引量:7
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作者 李昆锋 杨自春 《机械强度》 CAS CSCD 北大核心 2013年第2期174-178,共5页
在info-gap(information gap)模型中引入分散度参数,使其更适用于结构可靠性分析。基于info-gap理论,用引入分散度参数的info-gap模型描述参数的不确定性,建立一种统一的结构非概率可靠性模型。非概率可靠性指标可通过优化方法求解。通... 在info-gap(information gap)模型中引入分散度参数,使其更适用于结构可靠性分析。基于info-gap理论,用引入分散度参数的info-gap模型描述参数的不确定性,建立一种统一的结构非概率可靠性模型。非概率可靠性指标可通过优化方法求解。通过数学推导,揭示新建非概率可靠性模型与传统概率可靠性模型的内在联系和相容性。 展开更多
关键词 非概率可靠性 可靠性指标 info-gap(information-gap)模型 分散度
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图像边缘检测的多尺度灰度Gap统计模型 被引量:4
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作者 黄陈蓉 张正军 吴慧中 《中国图象图形学报》 CSCD 北大核心 2005年第8期1018-1023,共6页
汲取Hastie和Tibshiran i等人提出的“Gap statistic”的思想方法,利用样本灰度数据分布的差别定义多尺度的图像灰度间隙,在提出反分布函数概念的基础上,建立了图像边缘检测的多尺度灰度Gap统计模型。通过分析分布间隙和灰度间隙的一致... 汲取Hastie和Tibshiran i等人提出的“Gap statistic”的思想方法,利用样本灰度数据分布的差别定义多尺度的图像灰度间隙,在提出反分布函数概念的基础上,建立了图像边缘检测的多尺度灰度Gap统计模型。通过分析分布间隙和灰度间隙的一致性,优化了Gap统计模型的边缘检测算法。分析不同尺度下的检测结果,并比较了灰度Gap统计模型与Prew itt和Sobel边缘算子之间的相互关系。通过实例与分析,证明了该模型具有抗噪声、多尺度的特点。 展开更多
关键词 图像处理 边缘检测 gap统计 模型 多尺度
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图像分割的Gap统计模型 被引量:3
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作者 黄陈蓉 张正军 吴慧中 《计算机科学》 CSCD 北大核心 2005年第12期223-226,共4页
基于Hastie T.和Tibshirani R.等提出的"Gap statist"的思想,通过分析样本灰度数据分布的差别,提出了函数特征、间隙、总间隙及全间隙等概念,建立了图像分割的Gap统计模型,并给出了较为详细的算法。分析了图像分割Gap统计模... 基于Hastie T.和Tibshirani R.等提出的"Gap statist"的思想,通过分析样本灰度数据分布的差别,提出了函数特征、间隙、总间隙及全间隙等概念,建立了图像分割的Gap统计模型,并给出了较为详细的算法。分析了图像分割Gap统计模型中正则部分和奇异部分的特点,导出了区域特征自相似函数的分割结果与模型调节参数的关系。比较了用于图像分割的Gap统计模型与 Mumford-Shah模型,结果表明图像分割Gap统计模型的复杂度明显低于Mumford-Shah模型。 展开更多
关键词 图像分割 函数特征 自相似 gap统计 模型
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基于Info-Gap理论的地下结构稳健性分析方法 被引量:9
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作者 苏永华 李翔 《岩土工程学报》 EI CAS CSCD 北大核心 2011年第2期227-233,共7页
围绕基于Information-Gap(I-G)理论的地下结构稳健性方法展开研究。首先,根据地下结构输出响应模型中不确定参量可能的取值范围及不同波动幅度对结构安全性能的影响,采用I-G模型量化处理不确定参量;其次,通过地下结构失效准则确立输出... 围绕基于Information-Gap(I-G)理论的地下结构稳健性方法展开研究。首先,根据地下结构输出响应模型中不确定参量可能的取值范围及不同波动幅度对结构安全性能的影响,采用I-G模型量化处理不确定参量;其次,通过地下结构失效准则确立输出模型响应值与临界值之间的关系,由此构建稳健函数,并将结构发生失效前能够容许的不确定参量之最大波动幅度值定义为稳健可靠性指标来度量地下结构的可靠程度,从而形成了基于I-G理论的地下结构稳健性分析方法。最后,以某隧道衬砌稳健性分析为例,详细展示了地下结构稳健性分析的具体实施流程。工程算例表明,稳健可靠性指标反映了结构性能主动抵抗不确定性参量变化的能力。稳健性方法为不易得到不确定性因素足够信息的地下结构可靠性分析开辟了一条新途径。 展开更多
关键词 地下结构 不确定性分析 Information-gap模型 稳健函数 稳健可靠度指标 非概率可靠性
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基于GAP模型的轿车售后服务质量评价研究 被引量:3
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作者 陈力华 杨亚莉 《汽车工程》 EI CSCD 北大核心 2011年第1期85-90,共6页
在汽车售后服务质量理论研究的基础上,结合"GAP模型"和"SERVQUAL测量工具",采用层次分析法建立轿车售后服务质量评价模型。应用该模型对上海通用轿车售后服务质量进行评价。研究表明,售后服务质量与相应的服务费用... 在汽车售后服务质量理论研究的基础上,结合"GAP模型"和"SERVQUAL测量工具",采用层次分析法建立轿车售后服务质量评价模型。应用该模型对上海通用轿车售后服务质量进行评价。研究表明,售后服务质量与相应的服务费用是影响顾客满意度的主要因素。 展开更多
关键词 售后服务质量 gap模型 SERVQUAL测量工具 顾客满意度
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“两翼齐飞”在结肠肿瘤根治术无血管间隙寻找中的应用
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作者 贾静 李新宇 《中国肿瘤外科杂志》 2026年第1期31-35,共5页
该文主要探讨李新宇手术团队“两翼齐飞”模式在结肠癌手术中寻找无血管间隙的应用。“两翼齐飞”模式通过对器官、系膜的对称性牵拉,与主刀形成对抗张力,从而协助主刀能够快速寻找到目标器官与其系膜床、系膜融合边界的辨认,从而进入... 该文主要探讨李新宇手术团队“两翼齐飞”模式在结肠癌手术中寻找无血管间隙的应用。“两翼齐飞”模式通过对器官、系膜的对称性牵拉,与主刀形成对抗张力,从而协助主刀能够快速寻找到目标器官与其系膜床、系膜融合边界的辨认,从而进入到无血管的“神圣平面”,在无血条件下完成手术,既减少了组织损伤、减少术后并发症,又保证了肿瘤控制效果,确保长期治疗效果。 展开更多
关键词 腹腔镜手术 结肠癌手术 两翼齐飞 无血管间隙
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标准化水平Gap统计量的零件图像分割数估计 被引量:2
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作者 张正军 李建军 刘力维 《中国制造业信息化(学术版)》 2007年第10期146-149,共4页
针对零件图像最佳分割数估计问题,在Tibshirani等提出的Gap统计方法基础上,给出了Gap统计量需要考虑的4个因素,并据此建立了标准化水平Gap统计量模型,通过对零件最佳分割数的估计验证了该方法的有效性,比较了Gap统计模型和标准类方积Ga... 针对零件图像最佳分割数估计问题,在Tibshirani等提出的Gap统计方法基础上,给出了Gap统计量需要考虑的4个因素,并据此建立了标准化水平Gap统计量模型,通过对零件最佳分割数的估计验证了该方法的有效性,比较了Gap统计模型和标准类方积Gap模型,分析了标准类方积Gap模型的特性。 展开更多
关键词 零件 图像分割 gap统计 模型
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图像边缘检测的多尺度Gap统计方法 被引量:4
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作者 黄陈蓉 张正军 吴慧中 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2005年第6期1268-1272,共5页
基于Tibshirani等的“GapStatistic”思想,利用样本灰度数据分布差分析了图像分布间隙的规律,并在讨论随机含义下屋脊边缘和阶跃边缘等概念的基础上,建立了图像边缘检测的多尺度随机模型,给出了图像边缘检测算法.最后通过实例验证了该... 基于Tibshirani等的“GapStatistic”思想,利用样本灰度数据分布差分析了图像分布间隙的规律,并在讨论随机含义下屋脊边缘和阶跃边缘等概念的基础上,建立了图像边缘检测的多尺度随机模型,给出了图像边缘检测算法.最后通过实例验证了该模型的抗噪声与多尺度特性. 展开更多
关键词 gap统计 多尺度 边缘检测 图像处理 模型
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基于贝叶斯模型平均方法的主线汇入车辆间隙选择特征分析
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作者 廖彦锟 邹亚杰 +1 位作者 吴淑博 李林波 《交通与运输》 2026年第1期25-32,共8页
为解析车型差异对主线汇入间隙选择特征的影响,同时考虑到传统的单一模型拟合分布方法存在模型选择不确定性问题,应用贝叶斯模型平均(BMA)方法进行分车型汇入间隙分布建模:采集高速主线合流区车辆轨迹数据,提取四类(依车型划分)交互车... 为解析车型差异对主线汇入间隙选择特征的影响,同时考虑到传统的单一模型拟合分布方法存在模型选择不确定性问题,应用贝叶斯模型平均(BMA)方法进行分车型汇入间隙分布建模:采集高速主线合流区车辆轨迹数据,提取四类(依车型划分)交互车辆对时间与空间滞后间隙样本,构建候选分布概率密度函数模型空间;采用贝叶斯信息准则近似计算模型后验概率,综合加权得到BMA分布模型。结果表明:①主线汇入滞后间隙分布建模过程存在显著模型选择不确定问题,BMA方法可有效融合多模型优势,提升拟合稳健性;②滞后车类型与滞后间隙分布具有强相关性;③滞后车为小型车时,大型车汇入时较小型车汇入更有可能选择更小空间滞后间隙。 展开更多
关键词 高速公路 合流区 间隙选择 贝叶斯模型平均 车辆类型
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