Transportation Research Record最新文献

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Examining Transit Activity Data from StreetLight Using Ridership Data from Virginia Transit Agencies 使用弗吉尼亚州交通机构的乘客数据检查路灯的交通活动数据
4区 工程技术
Transportation Research Record Pub Date : 2023-10-24 DOI: 10.1177/03611981231197667
Afrida Raida, Peter B. Ohlms, T. Donna Chen
{"title":"Examining Transit Activity Data from StreetLight Using Ridership Data from Virginia Transit Agencies","authors":"Afrida Raida, Peter B. Ohlms, T. Donna Chen","doi":"10.1177/03611981231197667","DOIUrl":"https://doi.org/10.1177/03611981231197667","url":null,"abstract":"Researchers and planners require ridership data to study factors that influence people’s choice to use transit. However, the data can be challenging to obtain directly from transit agencies. Crowdsourced big data platforms such as StreetLight promise easily accessible ridership-related data in standard formats. It is important to assess the reliability of these data, particularly for transit agencies serving small- to medium-sized cities, which are less likely than agencies in large cities to have ridership data in standard formats. In this study, hourly ridership data from 2019 were collected from four bus transit agencies and one rail agency in Virginia and compared with StreetLight data. Comparisons for rail data were made on a station-to-station basis. Bus data comparisons were made at the city-limit level and at an aggregated-route level for each agency. In sum, StreetLight could not provide 2019 bus activity data for more than half of the localities in Virginia. Comparisons between transit agency and StreetLight data showed smaller root mean square errors when longer periods were analyzed (e.g., 4 versus 2 months). Although order of magnitude of ridership may indicate whether StreetLight can provide bus activity data, the former was not found to be correlated with the accuracy of the latter. Using data from StreetLight’s current algorithm might not be appropriate without verification against agency data, especially for agencies in small- to medium-sized cities.","PeriodicalId":23279,"journal":{"name":"Transportation Research Record","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135273107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Trajectory Planning Framework Combining Replanning and Hierarchical Planning 结合重规划和层次规划的轨迹规划框架
4区 工程技术
Transportation Research Record Pub Date : 2023-10-24 DOI: 10.1177/03611981231203228
Ping Qin, Fei Liu, Yuze Shang, Zhizhong Guo, Zhe Li
{"title":"Trajectory Planning Framework Combining Replanning and Hierarchical Planning","authors":"Ping Qin, Fei Liu, Yuze Shang, Zhizhong Guo, Zhe Li","doi":"10.1177/03611981231203228","DOIUrl":"https://doi.org/10.1177/03611981231203228","url":null,"abstract":"To enable autonomous vehicles to respond quickly to changes in the surrounding environment and to generate safe and stable trajectory, we propose a safety-based hierarchical trajectory planning method that divides the planning module into two parts: the planner and the replanning monitor. In the planner, we first propose a fast linear trajectory planning method that uses the mass point model instead of the vehicle model and linearizes the collision avoidance constraint using the Big-M method for linear programming (Big-M) to obtain a linear programming model. The complete vehicle kinematic model is then built in the nonlinear programming stage, the collision constraints and cost functions are refined, and the rough solution of the linear programming is brought into it to obtain the exact solution. The replanning monitor is divided into safety and comfort monitors. The safety monitor will always pay attention to the changes in the surrounding environment and calculate whether the vehicle is in danger of collision in the future period, while the comfort monitor is more concerned with the comfort of driving the vehicle; when the monitor requirements are not met, replanning will be carried out. By simulating the driving environment, the proposed algorithm can form a safe and comfortable trajectory, which verifies the rationality of the proposed method.","PeriodicalId":23279,"journal":{"name":"Transportation Research Record","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135267677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Examining the Effects of Local Sample Sizes on Spatial Transferability of Freight Production Models 考察地方样本量对货运生产模型空间可转移性的影响
4区 工程技术
Transportation Research Record Pub Date : 2023-10-21 DOI: 10.1177/03611981231197649
Bhavani Shankar Balla, Prasanta K. Sahu
{"title":"Examining the Effects of Local Sample Sizes on Spatial Transferability of Freight Production Models","authors":"Bhavani Shankar Balla, Prasanta K. Sahu","doi":"10.1177/03611981231197649","DOIUrl":"https://doi.org/10.1177/03611981231197649","url":null,"abstract":"Recent research in freight transportation planning has been exploring the spatial transferability of freight demand models, which can help the planning agencies of developing economies save the cost and time incurred in freight surveys. As the demand models are time-, cost-, and data-intensive, it is prudent to analyze the effects of sample size on the transferred model in a region. The findings and inferences from such analysis will save resources in freight data collection programs. Earlier, conventional models like ordinary least squares (OLS) regression were assessed for transferability. However, the predictive ability and transferability of such non-conventional models are not well studied. It is necessary to understand whether the extent of transferability of non-conventional models is greater than that of conventional models so that planning agencies can adopt more reliable modeling approaches. This paper investigates the spatial transferability of freight production models using OLS, robust regression, and multiple classification analysis (MCA). The results of the transferability assessment show that MCA models have better transferability using the naïve transfer method. In addition, transferability is assessed for different sample sizes to examine the variation in the extent of transferability. The MCA models have shown the least deviation, indicating that these models are preferred for transferability when the sample size is small.","PeriodicalId":23279,"journal":{"name":"Transportation Research Record","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135511733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
System Identification Framework for Modeling of Static Creep and Dynamic Creep Behavior of Dense-Graded Asphalt Mixtures 密级配沥青混合料静态蠕变和动态蠕变特性建模的系统识别框架
4区 工程技术
Transportation Research Record Pub Date : 2023-10-14 DOI: 10.1177/03611981231199476
Manoj K G
{"title":"System Identification Framework for Modeling of Static Creep and Dynamic Creep Behavior of Dense-Graded Asphalt Mixtures","authors":"Manoj K G","doi":"10.1177/03611981231199476","DOIUrl":"https://doi.org/10.1177/03611981231199476","url":null,"abstract":"The response of two dense-graded asphalt concrete (AC) mixtures under static and dynamic creep tests conducted in compression is modeled using the principles of the system identification framework in this study. The AC materials under static and dynamic creep loading conditions exhibit complex behavior patterns such as history dependency, plasticity, and temperature dependency. It is desired to formulate a constitutive model describing these complex phenomena. The empirical approach is outside the scope of this study. A viscoelastic continuum damage model requires individual experimentation to characterize linear and damage behavior. A viscoplastic model requires incremental deviator stress for plastic deformation. Both static and dynamic creep tests do not satisfy this condition. Therefore, the “system identification” approach is used in this study. Two methods of system identification approach—that is, black box and grey box modeling—are adopted to characterize static and dynamic creep behavior of AC. Of these two models under consideration, the black box models were versatile in modeling complex loading situations with a high degree of accuracy but lacked physical interpretation. While the grey box models have a physical interpretation, they are not as versatile as black box models.","PeriodicalId":23279,"journal":{"name":"Transportation Research Record","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135803998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
COVID-19 and Public Transport in Auckland, New Zealand: Investigating Vulnerable Population Groups’ Ridership Behavior 2019冠状病毒病与新西兰奥克兰公共交通:调查弱势群体的乘车行为
4区 工程技术
Transportation Research Record Pub Date : 2023-10-13 DOI: 10.1177/03611981231198465
Md Shahadat Hossain, Mahmudur Rahman Fatmi, Subeh Chowdhury
{"title":"COVID-19 and Public Transport in Auckland, New Zealand: Investigating Vulnerable Population Groups’ Ridership Behavior","authors":"Md Shahadat Hossain, Mahmudur Rahman Fatmi, Subeh Chowdhury","doi":"10.1177/03611981231198465","DOIUrl":"https://doi.org/10.1177/03611981231198465","url":null,"abstract":"Public transit ridership was severely affected during the COVID-19 pandemic in 2020 and the effects have continued since. The present study examines changes to ridership immediately post-pandemic in 2021. Research investigating the effects of COVID-19 on disadvantaged population groups is limited and the present study addresses this knowledge gap. Ridership of socially-disadvantaged groups such as low-income, female, and ethnic minority people is examined using order logit regression models. The study uses data from an online travel survey conducted in Auckland, New Zealand, immediately after all COVID-19-related restrictions were lifted. This allowed the collection of revealed preference data for the post-pandemic period. The regression models included the effects of socio-demographic characteristics of individual riders, travel attributes, and built environment factors. Findings suggest that those with lower income and from an ethnic minority group are likely to continue using transit frequently post-pandemic. Younger riders from the ethnic minority group are less likely to use transit frequently, while pre-COVID-19 they were more likely. Access to transit stops near home and work are significant factors for the ethnic minority group. Higher land use mix near the residence and work locations are found to induce more transit trips for all. It is critical for transit agencies to understand how the usage has evolved post-pandemic. These findings highlight the importance of considering the effects of the pandemic on different disadvantaged groups. Public transport service providers are encouraged to consider equity as they develop strategies to improve transit ridership.","PeriodicalId":23279,"journal":{"name":"Transportation Research Record","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135858313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Analysis of the Key Factors Influencing Automation Transformation in Container Terminals Based on the Dempster–Shafer Evidence Interval Method 基于Dempster-Shafer证据区间法的集装箱码头自动化改造关键影响因素分析
4区 工程技术
Transportation Research Record Pub Date : 2023-10-12 DOI: 10.1177/03611981231201113
Nanxi Wang, Kum Fai Yuen, Daofang Chang, Yinping Gao
{"title":"Analysis of the Key Factors Influencing Automation Transformation in Container Terminals Based on the Dempster–Shafer Evidence Interval Method","authors":"Nanxi Wang, Kum Fai Yuen, Daofang Chang, Yinping Gao","doi":"10.1177/03611981231201113","DOIUrl":"https://doi.org/10.1177/03611981231201113","url":null,"abstract":"The steady growth of container volume and aggressive shipping alliances have intensified competition among terminals. With the rapid development and application of modern information and communication technology, automation is a great way to promote terminals’ sustainable development. The objectives of this study are to analyze the key factors influencing automation transformation and provide theoretical guidelines for implementing automation transformation. Based on the literature review, the main factors influencing the automation transformation of container terminals are characterized and analyzed. They are divided into four categories: technical feasibility, external promotion, self-constraints, and goals/demand. Thereafter, a novel multi-source data fusion method, the Dempster–Shafer evidence interval method (DSIM) based on Dempster–Shafer evidence theory and interval value, is proposed to fuse conflicting and uncertain opinions among experts. This method is effective for expert opinion elicitation. Using DSIM, the key factors’ relative importance and their relationship are examined based on the opinions of experts in China. The results show that technical feasibility is the most important factor category in the foundation of automation transformation. Finally, a generalized planning framework for constructing automation transformation schemes is established, providing references and suggestions for terminals’ decision-makers.","PeriodicalId":23279,"journal":{"name":"Transportation Research Record","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135969407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Demographic Breakdown of Transit Rider Satisfaction 交通乘客满意度的人口统计分析
4区 工程技术
Transportation Research Record Pub Date : 2023-10-11 DOI: 10.1177/03611981231198836
Bianca Mers, Kari Watkins, Michael Hunter
{"title":"Demographic Breakdown of Transit Rider Satisfaction","authors":"Bianca Mers, Kari Watkins, Michael Hunter","doi":"10.1177/03611981231198836","DOIUrl":"https://doi.org/10.1177/03611981231198836","url":null,"abstract":"With ridership declining nationally and transit agencies looking for innovative ways to maintain and attract riders, a more complex understanding of transit riders and their satisfaction could provide additional insight and guidance to benefit the future of transit. This study challenged the traditional captive versus choice rider dichotomy and indicates the need for a more nuanced breakdown of transit riders based on the attributes most important to them. To conduct the analysis, the authors obtained rider survey data from nine agencies across the United States from varying geographic regions and representing various agency sizes. Agencies were selected based on their intentional use of demographic classifications and questions about satisfaction with various aspects of transit service. The authors then applied ordered logit regression across the 18,544 rider survey responses to predict the relative importance of service attributes on overall satisfaction. The findings suggested that different classifications of riders by gender, race, and income yielded diverse priorities, although certain service aspects such as reliability were important across demographics. In addition to the findings from the regression analysis, this study also offers a series of recommendations to facilitate future investigations by using more consistent, standardized data to further the breadth and depth of national transit rider analyses.","PeriodicalId":23279,"journal":{"name":"Transportation Research Record","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136209663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Effects of Environment-Friendly Rejuvenator on the Rheological Properties and Microstructure of Aged Asphalt 环保型再生剂对老化沥青流变特性和微观结构的影响
4区 工程技术
Transportation Research Record Pub Date : 2023-10-10 DOI: 10.1177/03611981231198835
Qiang Li, Dongxu Liu, Yuting Wen
{"title":"Effects of Environment-Friendly Rejuvenator on the Rheological Properties and Microstructure of Aged Asphalt","authors":"Qiang Li, Dongxu Liu, Yuting Wen","doi":"10.1177/03611981231198835","DOIUrl":"https://doi.org/10.1177/03611981231198835","url":null,"abstract":"The purpose of this paper is to explore the feasibility of using waste soybean oil and the multi-epoxy compound trimethylolpropane triglycidyl ether (TMPGE) compound as a rejuvenator to recycle aged styrene-butadiene-styrene (SBS)-modified asphalt, and to develop an environment-friendly SBS-modified asphalt rejuvenator (ESMAR) to achieve dual waste reuse. The optimum ratio of each component of ESMAR and the production conditions of the formulation were firstly determined by the orthogonal test method. To evaluate the rejuvenation effect of ESMAR, the physical properties and rheological properties of SBS-modified asphalt before and after rejuvenation were studied. Physical properties test results showed that ESMAR can effectively soften the aged asphalt and decrease its softening point and viscosity, as well as increase its needle penetration. As far as rheological properties are concerned, ESMAR could improve the low-temperature cracking resistance and fatigue resistance of aged SBS-modified asphalt; however, there was a certain reduction in the rutting resistance. The microscopic characteristics of the rejuvenation of ESMAR were analyzed by fluorescence microscopy, infrared spectroscopy, and gel permeation chromatography tests for the aged SBS-modified asphalt before and after rejuvenation, which showed that ESMAR can not only reconstruct the degraded SBS molecules in the aged SBS-modified asphalt, but also has a “dilution” effect on the aged asphalt.","PeriodicalId":23279,"journal":{"name":"Transportation Research Record","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136295699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Multidimensional Analysis of Willingness to Share Rides in a Future of Autonomous Vehicles 未来自动驾驶汽车共享出行意愿的多维分析
4区 工程技术
Transportation Research Record Pub Date : 2023-10-10 DOI: 10.1177/03611981231201111
Tassio B. Magassy, Irfan Batur, Aupal Mondal, Katherine E. Asmussen, Chandra R. Bhat, Ram M. Pendyala
{"title":"Multidimensional Analysis of Willingness to Share Rides in a Future of Autonomous Vehicles","authors":"Tassio B. Magassy, Irfan Batur, Aupal Mondal, Katherine E. Asmussen, Chandra R. Bhat, Ram M. Pendyala","doi":"10.1177/03611981231201111","DOIUrl":"https://doi.org/10.1177/03611981231201111","url":null,"abstract":"A sustainable transportation future is one in which people eschew personal car ownership in favor of using autonomous vehicle (AV)-based ridehailing services in a shared mode. However, the traveling public has historically shown a disinclination toward sharing rides and carpooling with strangers. In a future of AV-based ridehailing services, it will be necessary for people to embrace both AVs as well as true ridesharing to fully realize the benefits of automated and shared mobility technologies. This study investigated the factors influencing willingness to use AV-based ridehailing services in the future in a shared mode (i.e., with strangers). This was done through the estimation of a behavioral model system on a comprehensive survey data set that included rich information about attitudes, perceptions, and preferences pertaining to the adoption of AVs and shared mobility modes. The model results showed that current ridehailing experiences strongly influenced the likelihood of being willing to ride AV-based services in a shared mode. Campaigns that provide opportunities for individuals to experience such services firsthand would potentially go a long way to enabling a shared mobility future at scale. In addition, several attitudinal variables were found to strongly influence the adoption of future mobility services; these findings provide insights on the likely early adopters of shared autonomous mobility services and the types of educational awareness campaigns that may effect change in the prospects of such services.","PeriodicalId":23279,"journal":{"name":"Transportation Research Record","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136353362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Using Spatial Modeling for Identifying Determinants Influencing Crash Estimate: Case Study of Hamedan, Iran 利用空间模型识别影响事故估计的决定因素:以伊朗哈马丹为例
4区 工程技术
Transportation Research Record Pub Date : 2023-10-07 DOI: 10.1177/03611981231197647
Seyed Ahmadreza Almasi, Amir Reza Bakhshi Lomer, Hassan Khaksar, Aynaz Lotfata
{"title":"Using Spatial Modeling for Identifying Determinants Influencing Crash Estimate: Case Study of Hamedan, Iran","authors":"Seyed Ahmadreza Almasi, Amir Reza Bakhshi Lomer, Hassan Khaksar, Aynaz Lotfata","doi":"10.1177/03611981231197647","DOIUrl":"https://doi.org/10.1177/03611981231197647","url":null,"abstract":"Road crashes are a major cause of fatalities worldwide, posing significant challenges for road-safety experts in selecting appropriate crash-frequency estimation models. This study introduces localized safety performance functions (C-SPFs), which explore the spatial variation of crash frequency and the spatial correlation between dependent variables. The exploratory spatial regression method is employed to identify optimal spatial associations. The study further predicts crashes using geographically weighted Poisson regression (GWPR) and generalized Poisson regression. Results indicate that C-SPFs offer greater accuracy than do models calibrated solely on annual average daily traffic. Moreover, the proposed model is especially relevant for jurisdictions facing higher heavy-vehicle traffic and frequent crashes. The development of C-SPFs and the use of GWPR provide valuable tools for policymakers and road-safety experts in enhancing crash-frequency estimation accuracy. Implementing these techniques can aid in prioritizing safety measures and countermeasures, especially in regions with significant heavy-vehicle traffic and crash occurrences. Additionally, the integration of spatial-analysis techniques and localized models can lead to more effective transportation planning and targeted road-safety interventions, ultimately contributing to reducing the burden of road crashes on a global scale.","PeriodicalId":23279,"journal":{"name":"Transportation Research Record","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135252410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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