Built environment impact on the per capita cycling frequency of family--Based on two-level hierarchical linear model.

At present, there is less attention paid to the relationship between the frequency of travel and built environment, especially in households. In this paper, some of the determining factors in the frequency of daily cycling per household were explored based on the data from 2018 Daily Trip Survey in Xianyang, China. Then a two-level linear model was construct to identify the determining factors in the frequency of per capita daily cycling of household. According to the research results, 22.8% of the differences in the per capita cycling frequency of household are due to the differences between communities. In terms of community factors, the densities of road networks and educational facilities delivered a significantly positive impact on the per capita daily cycling frequency of family; on the contrary, the densities of medical facilities, intersections and POI delivered a significantly negative impact. Per capita cycling frequency varies considerably between households. For instance, the number of bicycles owned and the number of school-age children have a significantly positive impact on the per capita daily cycling frequency of family. However, car ownership, household income and occupation composition impose a significantly negative impact. The findings of this study would benefit the transportation engineers and planners who are keen to boost the use of active means of transportation for residents.

Optimized low-dose positron emission tomography/computed tomography schemes in pediatric tumor patients: a randomized clinical trial.

Background: It's clinically relevant to reduce the radiation dose to children while ensuring their positron emission tomography/computed tomography (PET/CT) image quality. The optimal protocol for whole-body PET/CT imaging in children (non-model) has been less studied. In this study, we investigated the optimal protocol for PET/CT imaging of pediatric oncology by analyzing the radiation dose and image quality in18F-fluoro-2-deoxy-D-glucose (18F-FDG) PET/CT imaging of children with oncology. Methods: One hundred children with tumors who underwent 18F-FDG PET/CT were included. CT grouping: randomly divided into 18 groups A-R according to the combination of three parameters: tube voltage (80/120 kV), automatic milliamp range (20-39/40-59/60-80 mA), and noise index (NI) (8/12/14). PET grouping: randomly divided into 9 groups a-i according to the combination of two parameters: the pharmaceuticals injection dose (0.08/0.12/0.15 mCi/kg) and time per bed (120/150/180 s). The effective radiation dose (ED) was calculated separately for each group and the image quality of CT and PET was evaluated subjectively using standard deviation (SD) and coefficient of variation (CV) objective evaluation and 5-point evaluation method, respectively. Results: Ninety-seven images in CT and 57 images in PET were included. The best quality of CT images was in group K (120 kV/40-59 mA/8); there are 9 groups had good image quality and lower dose length product (DLP) than group K (SD ±10), while the difference in DLP between groups was large. The Kruskal-Wallis (K-W) test showed that the difference in image quality between the 9 groups was not statistically significant. The best PET image quality was in group i [0.15 (mCi/kg)/180 s]; there are four groups had good image quality and lower EDPET than group i (CV ±3.5%), while the difference in EDPET between groups was large (4.4-6.5 mSv), and the K-W test showed that the difference in image quality between the four groups was not statistically significant (P>0.05), with the lowest EDPET being in the g group. Conclusions: The optimal protocols for CT scanning and PET imaging in this experiment were group H (80 kV/40-59 mA/14) and group g [0.08 (mCi/kg)/180 s], respectively.Trial Registration: Chinese Clinical Trial Registry ChiCTR2200061386.

Understanding the intention to use bike-sharing system: A case study in Xi'an, China.

Bike-sharing is widely recognized as an eco-friendly mode of transportation and seen as one of the solutions to the problem of air pollution and congestion. With the emphasis on sustainability in transportation, bike-sharing systems is an emerging topic of urban transport and sustainable mobility related research. Existing studies mainly explored the factors affecting individuals' initial intentions to start using a shared bicycle, but few looked at the likelihood that a user would continue using one This study proposed a structural equation model with bike-sharing purchase decision involvement as independent variable, bike-sharing willingness to use as dependent variable, traveler participation and traveler perceived value as intermediary variables by introducing the concepts of purchase decision involvement, customer participation and perceived value in consumer psychology and behavior. A survey on bike-sharing users in Xi'an was conducted online and offline, and 622 effective responses were collected. The research model was tested by Amos 24.0 and the empirical results showed that All influencing factors including bike-sharing's purchase decision-making involvement, traveler participation and traveler's perceived value are found to be significantly and positively associated with usage intention; traveler perceived value play a chain-mediating role between bike-sharing purchase decision involvement and usage intention; bike-sharing purchase decision involvement have indirect effects on traveler perceived value through traveler participation. The results of this study enrich the current research's in the field of sharing economy, and it is certain guiding significant for how to obtain and maintain stable customers in bicycle-sharing industry.

Correction: Research on parking sharing strategies considering user overtime parking.

[This corrects the article DOI: 10.1371/journal.pone.0233772.].

Research on parking sharing strategies considering user overtime parking.

A parking sharing strategy is proposed to solve the problems of parking difficulty caused by the imbalance between parking spaces and parking demand. The vacant parking spaces of residential area can be efficiently utilized to meet the parking demands of those who are working at nearby or come for other activities based on the parking sharing strategy. The paper analyzes the distribution of vehicle arrival numbers and parking durations, then establishes a shared parking allocation model aiming to maximize the parking benefit considering the overtime-parking behavior of the parking users. Simulation methods are used to the analyze the relationship among the parking benefit, proportion of reserved parking, numbers of parking demand, acceptance rate of parking demand and utilization of shared parking spaces. Then, based on the principle of maximum parking benefit, we can determine the optimal proportion of reserved parking, number of shared parking spaces that should be purchased from the residents. Taking the utilization of shared parking spaces as an indicator, the validity of the static allocation principle is proved to be effective. Some allocation rules for parking demand are proposed to guarantees the maximum parking revenue and minimum impact on residents simultaneously.