Transportation Research Part A-Policy and Practice最新文献

{"title":"Improving public transportation via line-based integration of on-demand ridepooling","authors":"Andres Fielbaum ,&nbsp;Alejandro Tirachini ,&nbsp;Javier Alonso-Mora","doi":"10.1016/j.tra.2024.104289","DOIUrl":"10.1016/j.tra.2024.104289","url":null,"abstract":"<div><div>Ride-sourcing companies have worsened congestion in numerous cities worldwide, as many users are attracted from more sustainable modes. To reverse this trend, it is crucial to leverage the technology of connecting users and vehicles online and use it to strengthen public transport, which can be achieved by integrating on-demand pooled services with existing fixed-line services. We propose an efficient and practical integration idea: namely, to complement fixed bus lines with a fleet of smaller vehicles that follow flexible (on-demand) routes side-by-side with the fixed routes, so that part of the demand that would have used the fixed line can ride the flexible service instead. With this scheme, a smaller bus fleet is required, partially compensating for the increase in operators’ costs stemming from the flexible vehicles. This integration strategy favors mostly two types of users: those traveling in low-demand periods, through lower waiting times, and those located far from the bus stops, because the on-demand vehicles can reduce their access time. We develop simulations in real-world scenarios from Santiago, Chile, and Berlin, Germany, for the cases of human-driven and automated vehicles. Results show that when vehicles are automated: (i) A small number of on-demand vehicles can reduce average walking times from approximately 12 to 2 min while reducing operators’ costs, leading to a Pareto improvement, (ii) A larger number of on-demand vehicles can diminish total costs by 13%–39%, through a reduction in users’ costs, although increasing operators’ costs. If vehicles are not automated, total costs are reduced by more than 10% in all of the scenarios analyzed, but a Pareto improvement is not always possible. In general, this mixed fixed/on-demand system outperforms the use of on-demand ridepooling only. Results are more promising in Berlin, because large buses are cheaper in Santiago and run more crowded, so it is more costly to partially replace them by smaller vehicles.</div></div>","PeriodicalId":49421,"journal":{"name":"Transportation Research Part A-Policy and Practice","volume":"190 ","pages":"Article 104289"},"PeriodicalIF":6.3,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142573356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How has COVID-19 changed individuals’ e-commerce and shopping mobility habits? Evidence from Madrid Region","authors":"José Cano-Leiva,&nbsp;Juan Gomez,&nbsp;Guilherme F. Alves,&nbsp;José Manuel Vassallo","doi":"10.1016/j.tra.2024.104295","DOIUrl":"10.1016/j.tra.2024.104295","url":null,"abstract":"<div><div>The use of e-commerce has grown exponentially in recent years, driven by the increase in Internet connectivity and the spread of electronic payment mechanisms. Lockdowns and social distancing measures imposed during the COVID-19 health crisis led to an extra growth in the use of e-shopping among the population, some of which has continued after the end of the pandemic. E-commerce practices have been found to influence mobility patterns of individuals, with many contributions having analyzed their effects on shopping trips before the pandemic and during COVID waves. However, there is a need to understand the lasting changes in individuals’ patterns of e-commerce as well as their subsequent impact on mobility in the aftermath of the pandemic. To that end, this research takes advantage of a macro survey campaign in the Region of Madrid, Spain between October and November 2022, collecting 15,666 valid responses in a fully post-COVID timeframe. This information was exploited to build a Generalized Structural Equation Model (GSEM) that explores individuals’ patterns of e-commerce use in two different time periods, pre- and post-COVID, with the aim of studying to what extent changes in e-commerce and shopping habits have modified individuals’ mobility patterns. The research concludes a positive, albeit modest, effect of the pandemic on e-commerce usage among the population, as well as an increased preference for shopping physically close to home. Reductions in shopping mobility are greater among intensive users of e-commerce and people who before COVID mainly used the private car or public transport for shopping trips, thus suggesting a positive impact on sustainability from the demand side. The paper provides additional insights on the relationships between shopping habits, e-commerce use, and reductions in the mobility of individuals due to the availability of e-commerce, of interest to researchers and policymakers.</div></div>","PeriodicalId":49421,"journal":{"name":"Transportation Research Part A-Policy and Practice","volume":"190 ","pages":"Article 104295"},"PeriodicalIF":6.3,"publicationDate":"2024-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142561029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How public transport users would react to different pandemic alert scenarios in the post-vaccine era? An analysis of preferences and attitudes of the users in the metropolitan area of Naples (Italy)","authors":"Fiore Tinessa ,&nbsp;Concepción Román Garcia ,&nbsp;Fulvio Simonelli ,&nbsp;Andrea Papola ,&nbsp;Francesca Pagliara","doi":"10.1016/j.tra.2024.104301","DOIUrl":"10.1016/j.tra.2024.104301","url":null,"abstract":"<div><div>The dramatic experience due to COVID-19 spread has reshaped travel preferences of public transport (PT) users worldwide, especially in urban areas. As the PT is expected to recover its major role in such areas, it is important to understand the factors influencing PT users’ willingness to pay (WTP) for onboard safety measures, in the event of future pandemic scenarios. Furthermore, both individual latent traits (e.g. concern for the pandemic, trust/distrust in city services and national government actions) and perceived entity of the pandemic are expected to influence preferences for PT users under such a post-pandemic scenario. This paper analyses the preferences and attitudes of PT users in the Naples metropolitan area (Italy) through a hybrid choice model (HCM). First, WTPs for onboard service features are assessed in three hypothetical pandemic alert scenarios, which are explicitly introduced in the model as context variables. Second, the model allows for assessing the relative importance of onboard characteristics as the pandemic scenario evolves. Third, the model incorporates psycho-attitudinal variables and shows how they impact WTPs. Finally, several policy implications for policymakers and transport companies operating in the study area are derived. In particular: (a) WTPs for increased/reduced occupancy rate and green pass check at the entrance significantly depend upon the latent traits investigated; (b) relative importance of safety measures varies significantly between the pandemic alert scenarios; (c) possible ticketing strategies for PT users have been investigated based on the HCM findings, searching for the configuration of safety measures to ensure that users accept a 100% allowed capacity on board during moderate/high pandemic scenarios without varying the price, as well as the price variations needed to stay in an indifference range of the utility in restricted conditions of the service; (d) the acceptability of safety measures has been assessed through a simulation exercise, finding that non-vaccinated travellers are 2.6 and 2.1 times more willing to accept a full capacity of the buses/trains on board than vaccinated people if subscribers or not, respectively.</div></div>","PeriodicalId":49421,"journal":{"name":"Transportation Research Part A-Policy and Practice","volume":"190 ","pages":"Article 104301"},"PeriodicalIF":6.3,"publicationDate":"2024-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Long-distance mode choice estimation on joint travel survey and mobile phone network data","authors":"Angelica Andersson ,&nbsp;Ida Kristoffersson ,&nbsp;Andrew Daly ,&nbsp;Maria Börjesson","doi":"10.1016/j.tra.2024.104293","DOIUrl":"10.1016/j.tra.2024.104293","url":null,"abstract":"<div><div>The accuracy of a transport demand model’s predictions is inherently limited by the quality of the underlying data. This issue has been highlighted by the decline in response rates for transport surveys, which have traditionally served as the primary data source for estimating transport demand models. At the same time, mobile phone network data, not requiring active participation from subjects, have become increasingly available. However, some key trip and traveller characteristics enhancing the prediction power of the estimated models are not collected in mobile phone network data. In this paper we therefore investigate what can be gained from combining mobile phone network data with travel survey data, using the strengths of each data source, to estimate long-distance mode choice models. We propose and estimate a set of mode choice demand models on joint mobile phone network data and travel survey data. We show that combining the two data sources produces more credible estimates than models estimated on each data source separately. The travel survey should preferably include the variables: travel party size, cars per household licence, licence holding, in addition to origin, destination, mode, trip purpose, age, and gender of the respondent.</div></div>","PeriodicalId":49421,"journal":{"name":"Transportation Research Part A-Policy and Practice","volume":"190 ","pages":"Article 104293"},"PeriodicalIF":6.3,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Potential short- to long-term impacts of on-demand urban air mobility on transportation demand in North America","authors":"Kexin Chen ,&nbsp;Ali Shamshiripour ,&nbsp;Ravi Seshadri ,&nbsp;Md Sami Hasnine ,&nbsp;Lisa Yoo ,&nbsp;Jinping Guan ,&nbsp;Andre Romano Alho ,&nbsp;Daniel Feldman ,&nbsp;Moshe Ben-Akiva","doi":"10.1016/j.tra.2024.104288","DOIUrl":"10.1016/j.tra.2024.104288","url":null,"abstract":"<div><div>This study applies an agent-based approach to investigate the potential individual-level demand for and system-wide impacts of Urban Air Mobility (UAM) in the short- to long-term, in two real U.S. metropolitan areas. The UAM service we envision in this research provides mobility to on-demand requests from one vertiport to another. The investigations consider the existing electric vertical take-off and landing (eVTOL) aircraft models (assuming they are piloted) and vertiport designs, while accounting for the uncertainties in (i) service attributes (e.g., time saving and service price), and (ii) demand characteristics (e.g., perceived waiting time in various conditions). Towards this goal, the state-of-the-art agent-based simulation platform SimMobility is expanded in this research with new modules required for realistic simulation of the demand, supply, and demand–supply interactions. The expanded platform adopts a high-fidelity model system with: (i) a behaviorally sound demand model to mimic the switching behavior from current non-UAM mode to UAM and to capture the individuals’ willingness to pay and plan-action dynamics in decision-making; (ii) a detailed operation model to account for not only the integration of ground and aerial transportation but also fleet rebalancing and the intra-vertiport state dynamics such as charging, gate availability, taxiing, pre-landing hovering (as a result of capacity limitations), etc.; (iii) a demand-driven vertiport placement and capacity generation module. The results show that the UAM market is expected to start narrow (0.187 % to 0.197 % of all trips) and remain niche in the long term (1.45 % to 1.81 % of all trips) for both cities. In addition, the service is expected to increase mobility inequality, even in the long term. The potential UAM users turned out to be primarily high-income in all scenarios (e.g., 46.9 % to 59.2 % in the long term). Moreover, car-oriented individuals are identified as the main users – not only are most UAM trips expected to emerge from drive-alone trips (84.7 % to 92.8 % at launch), but also drive-alone is expected to be the most preferred access/egress mode (78.4 % to 83.6 % share among all UAM trips at launch). Notably, short-range UAM trips (i.e., flight distance below 40 km) constitute the majority of the UAM potential demand (94.6 % in the long-term scenario).</div></div>","PeriodicalId":49421,"journal":{"name":"Transportation Research Part A-Policy and Practice","volume":"190 ","pages":"Article 104288"},"PeriodicalIF":6.3,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development and safety evaluation of an adaptive personalized speed guidance system for on-ramp merging in highway service areas","authors":"Haoran Li ,&nbsp;Tengfa Xiao ,&nbsp;Yaqiu Li ,&nbsp;Yuanjun Feng","doi":"10.1016/j.tra.2024.104296","DOIUrl":"10.1016/j.tra.2024.104296","url":null,"abstract":"<div><div>As autonomous driving and Vehicle-to-Everything (V2X) technologies evolve, the efficiency and safety of ramp merging in the highway service areas have become increasing critical. This study introduces a closed-loop feedback speed guidance system that accommodates individual driving styles, aiming to optimize merging behaviour, reduce traffic accidents, and enhance total traffic efficiency. The system dynamically adjusts the merging vehicle speeds by continuously monitoring their speed and location with variable steps to promote smoother merging. Moreover, this research also involves collecting naturalistic driving data from ramp merging scenarios, using the K-means clustering and point estimation method to recognize and analyse driving style characteristics, and integrating these styles into the developed closed-loop feedback speed guidance system. This approach results in personalized speed guidance curves tailored to different driving styles, facilitating more efficient mering. Additionally, the study conducts a Safety of the Intended Functionality (SOTIF) evaluation of this system using the System-Theoretic Process Analysis (STPA) method, which helps identify potential security risks and develop appropriate mitigation strategies to ensure the system’s safe and stable operation. The simulation results confirm that this innovative dynamic speed guidance system substantially improves traffic safety and efficiency in ramp merging areas.</div></div>","PeriodicalId":49421,"journal":{"name":"Transportation Research Part A-Policy and Practice","volume":"190 ","pages":"Article 104296"},"PeriodicalIF":6.3,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142529615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Housing choice in an evolving remote work landscape","authors":"Dale Robbennolt,&nbsp;Angela J. Haddad,&nbsp;Aupal Mondal,&nbsp;Chandra R. Bhat","doi":"10.1016/j.tra.2024.104285","DOIUrl":"10.1016/j.tra.2024.104285","url":null,"abstract":"<div><div>We estimate a joint model of housing choice along several dimensions to account for changing valuations of housing outcomes due to the COVID-19 pandemic. We consider housing outcomes including housing type, tenure type, the presence of a patio or yard, the number of bedrooms, neighborhood population density, median housing cost, accessibility of amenities, school quality, crime rate, and commute distance. Data used for this analysis were collected in October and November of 2021 from 24 metropolitan areas across the United States. A Generalized Heterogeneous Data Model (GHDM) is used to estimate these housing outcomes as a function of exogenous household sociodemographic characteristics and latent lifestyle propensities. The GHDM also captures jointness caused by unobserved factors, allowing for the estimation of accurate causal effects between outcomes. The results reveal that lifestyle preferences have significant impacts on housing outcomes. Specifically, individuals with a preference for teleworking are more likely to reside in single-family homes in highly populated areas, experience longer commute distances, and exhibit a higher sensitivity to the presence of amenities in their neighborhoods. Additionally, the analysis of tradeoffs between housing outcomes reveals the relative valuations of various housing outcomes. An increased commute distance is found to lead to an increase in single-family homes, reductions in density, and an increased crime rate. Choosing an apartment in a high-density neighborhood is found to lead to reductions in school quality and significant increases in crime rates. Implications of the results for land-use planning, travel demand analysis, and equity considerations are identified and discussed.</div></div>","PeriodicalId":49421,"journal":{"name":"Transportation Research Part A-Policy and Practice","volume":"190 ","pages":"Article 104285"},"PeriodicalIF":6.3,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142529616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inferring spatial–temporal attributes of vehicle itinerary with Automatic Vehicle Identification data: Methodology and application","authors":"Qi Cao ,&nbsp;Yang Liu ,&nbsp;Gang Ren ,&nbsp;Shunchao Wang ,&nbsp;Dawei Li ,&nbsp;Yue Deng ,&nbsp;Xiaobao Qu","doi":"10.1016/j.tra.2024.104264","DOIUrl":"10.1016/j.tra.2024.104264","url":null,"abstract":"<div><div>Daily itinerary, consisting of an individual’s trips and activities on a day, is usually fundamental input for many travel demand models. However, current research lacks effective methods to extract daily itineraries of large-scale samples for a long period. To this end, this study presents a methodology to Infer Daily Itineraries (IDI) of vehicles with Automatic Vehicle Identification (AVI) data. A problem-specific Probabilistic Graphical Model is constructed to define how possible one itinerary is true given its observed AVI data. To seek the most possible itinerary among vast feasible states, a candidate movement state generation algorithm and optimal itinerary searching algorithm are developed. Empirical studies have been conducted based on field-test data. Compared with two benchmarks, the proposed IDI improved the inference accuracy significantly even for activities with missing observations. Sensitivity analyses on the size of traffic area zone and data collection have also been performed, which can provide guidance for administrations and researchers on the partition of the study region and placement of the sensors. As the AVI system captures almost entire samples, vehicle movements inferred by IDI can provide a better representation of traffic patterns. This enables a series of applications related to transportation policy and practice. Traffic congestion tracking and parking demand estimation are introduced as two application examples.</div></div>","PeriodicalId":49421,"journal":{"name":"Transportation Research Part A-Policy and Practice","volume":"190 ","pages":"Article 104264"},"PeriodicalIF":6.3,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142529614","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Greening the commute: A case study of demand for employer-sponsored microtransit","authors":"Andre L. Carrel ,&nbsp;Stavroula M. Mavrouli ,&nbsp;Priyamvada R. Natarajan ,&nbsp;Rana Tarabay ,&nbsp;Andrea Broaddus","doi":"10.1016/j.tra.2024.104258","DOIUrl":"10.1016/j.tra.2024.104258","url":null,"abstract":"<div><div>Demand-responsive, pooled, app-based transportation services, often known as microtransit, fill a gap in providing public transportation where fixed-route transit services are weak. While prior research mostly focused on public-access microtransit services, little is known about the potential of restricted-access, employer-sponsored services to achieve mode shifts away from driving. This study investigates the possible use of employer-sponsored microtransit service by commuters who currently drive to work, using data from a stated choice experiment conducted at a major medical center in Columbus, Ohio. The results reveal a considerable interest in a hypothetical microtransit commuter service among medical center employees, with on average 29.6% of them shifting from car to microtransit. Overall, relatively few sociodemographic characteristics are found to correlate with interest in employer-sponsored microtransit use, but income, status as a shift worker, and a desire to work while commuting are found to affect choice. Valuations of in-vehicle travel time, flexibility in drop-off/pick-up time, and stop location are calculated and compared to prior results from the transit literature. Such valuations can serve as inputs for optimization models to design microtransit systems. Furthermore, respondents’ potential concerns about a microtransit service and reactions to proposed incentive schemes are analyzed. The study results highlight the value of combining employer-sponsored microtransit implementations with transportation demand management strategies that reduce the attractiveness of commuting by car. The findings suggest that employer-sponsored microtransit represents an opportunity to reduce greenhouse gas emissions and congestion in an industry sector that employs 6.6 million workers in the US.</div></div>","PeriodicalId":49421,"journal":{"name":"Transportation Research Part A-Policy and Practice","volume":"190 ","pages":"Article 104258"},"PeriodicalIF":6.3,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142529613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fleet sizing and static rebalancing strategies for shared E-scooters: A case study in Indianapolis, USA","authors":"Yuhang Wu ,&nbsp;Tao Liu ,&nbsp;Bo Du","doi":"10.1016/j.tra.2024.104287","DOIUrl":"10.1016/j.tra.2024.104287","url":null,"abstract":"<div><div>With the rapid development of shared e-scooters, it is essential to understand their usage patterns for formulating informed e-scooter fleet management policies. This study first analyzes the usage pattern of shared e-scooters in Indianapolis, USA, by mining big e-scooter trip data. The analysis reveals an oversupply of shared e-scooters relative to actual user demand. Thus, a minimum fleet sizing algorithm is proposed to determine the required minimum e-scooter fleet size with the objective of reducing total operation cost, while ensuring demand coverage. Furthermore, three heuristic algorithms are proposed to address the static e-scooter rebalancing problem, focusing on minimizing rebalancing distance cost and rebalancing time. These algorithms consider practical operational constraints, including the number of rebalancing vehicles, their capacity, and the frequency of visits to e-scooter stations by rebalancing vehicles. The proposed algorithms are applied to e-scooter rebalancing scenarios with comparisons between the minimum and actual fleet sizes. The case study results in Indianapolis, USA demonstrate that the rebalancing distance cost with the minimum fleet size is significantly lower than that with the actual fleet size. What’s more, the rebalancing time can be reduced by about 12.34% to 27.80% when using the minimum fleet size. The findings of this study offer valuable policy implications and managerial insights for shared e-scooter operators and policymakers in developing effective e-scooter management strategies.</div></div>","PeriodicalId":49421,"journal":{"name":"Transportation Research Part A-Policy and Practice","volume":"190 ","pages":"Article 104287"},"PeriodicalIF":6.3,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142529612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}