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Purposes The sparse feature map established by using VSLAM cannot be directly used for navigation, and the existing methods of converting sparse feature maps into grid maps for navigation suffer from low accuracy of map construction, resulting in the failure to achieve accurate navigation. An improved ORB-SLAM3 navigation method is proposed based on multi-convex combined maximum correntropy criterion (MCMCC), which can realize the construction, positioning, and navigation of indoor real-time mapping on the embedded device with only a RGB-D camera. Methods The proposed method uses the back-end optimization algorithm based on MCMCC to combat the influence of non-Gaussian noises and to further improve the mapping accuracy of ORB-SLAM. Subsequently, in the process of converting the sparse feature map into a grid map, the grid map is updated with the loop detection information to improve the grid map accuracy for accurate navigation. Findings Furthermore, simulation and real scene experiments have been carried out to verify the effectiveness of the proposed method.

In the field of collaborative visual simultaneous localization and mapping (CVSLAM), efficient data communication poses a significant challenge, particularly in environments with limited bandwidth. To address this issue, we introduce a method aimed at reducing communication consumption. Our approach starts with a strategic culling of map points, aiming at maximizing pose-visibility and expanding spatial diversity to effectively eliminate redundant data in CVSLAM. We achieve this by formulating the problem of maximizing pose-visibility and spatial diversity as a minimum-cost maximum-flow graph optimization problem. Subsequently, we apply finite state entropy encoding for the compression of visual information, further alleviating bandwidth constraints. To verify the proposed method, we implement it within a centralized collaborative monocular simultaneous localization and mapping (SLAM) system. Our approach has been tested on publicly available datasets and in real-world scene. The results show a prominent reduction in bandwidth usage by 49% while maintaining mapping accuracy and without introducing additional latency, confirming its effectiveness in a multi-agent system setting. [ABSTRACT FROM AUTHOR]

In order to obtain a strawberry fruit wine with strong aroma and typical flavor, the non-fermentative yeast, Torulaspora delbrueckii (Td), was sequentially co-fermented with four commercial wine yeasts (D254, K1, F15, and Aq) at a 1:1 inoculation ratio.The effects of the four mixed fermentation combinations on the physicochemical properties, volatile aromatic compounds, and consumer preferences of strawberry wines were evaluated using SPME-GC-MS and a 9-point hedonic scale.The results show that the co-fermentation of Td with different wine yeasts significantly affects the color and aroma components of strawberry wine.Sequential inoculation with Td and Aq or D254 resulted in a wine with a higher redness and saturation.For aroma, a total of 67 volatile compounds, mainly esters, alcohols and acids, were identified in the four strawberry wines.Based on the Venn diagram analysis, 19 aroma compounds were common to all four wine samples, with the Td+D254 combination producing the highest number of aroma compounds (48).The principal component analysis of major aroma compounds (ROAV>0.1) revealed that the volatile active compounds produced by Td+K1 group and Td+D254 group were similar, and closely related to octanoic acid, nonanal, and S-(-) -2-methyl-1-butanol, etc.The consumer preference test showed that the Td+D254 group of strawberry wine had strong fruity, refreshing, and floral aromas, achieving the highest preference score 6.7±1.2.Overall, the findings suggest that the combined fermentation of Td and Saccharomyces cerevisiae D254 has the potential to enhance the aromatic qualities of strawberry wine. [ABSTRACT FROM AUTHOR]

This study focuses on the different impacts of platform training and learning by doing on gig workers' platform income. Based on survey data of China's delivery riders on the platform in 2020, via quantitative methods combined with the case study, it is found that the platform training is negatively correlated with riders' incomes, while learning by doing is positively correlated with their incomes. Workers with a high level of platform-income dependence earn more than those with an average level of dependence under the same platform training, or learning by doing. Overall, the incomes of the former are significantly lower than those of the latter, where the difference is mainly due to unobservable factors. Both platform training and learning by doing significantly reduce the income gap. In addition, the instrumental variable and the propensity score matching approaches are introduced to handle the endogeneity problem, and robust results are obtained. Plain language summary: Influence of learning by doing and platform training on gig workers' incomes This study looks at how two different ways of learning affect gig workers' earnings on platforms. We used data from a survey of delivery riders in China in 2020. We found that training provided by the platform tends to lower riders' earnings, while learning from actual work experience tends to increase earnings. Riders who rely more on their platform income earn more than those who don't, even after training or learning by doing. Both types of learning help reduce the income gap. We used special methods to make sure our results are accurate. [ABSTRACT FROM AUTHOR]

Limited by the low-frequency data acquisition, vehicle global positioning system (GPS) data are difficult to implement in the area of microtraffic simulation. Based on the functional design of mobile phone positioning technology, mobile phones can be used to acquire bus GPS data every second. In this paper, an analytical model is proposed to determine the parameters of signal coordination for bus priority along an arterial based on GPS data of mobile phones. First, bus priority evaluation indicators are established using bus GPS data, which are acquired by mobile phones. Second, the signal timing parameters of the arterial road are optimized, and a preliminary timing plan is developed by evaluating small changes in the plan. Finally, the corresponding final plan is developed using VISSIM micro simulation software. The feasibility of the analytical model is verified by simulating an actual arterial in Fuzhou city, China. Key words: bus signal priority, modeling, signal timings, mobile phone GPS data, micro simulation. Les donnees du systeme de positionnement global (GPS) des vehicules, limitees par l'acquisition de donnees a basses frequences, sont difficiles a mettre en oeuvre dans le domaine de la simulation de micro-trafic. Base sur la conception fonctionnelle de la technologie de positionnement de telephones mobiles, ces derniers peuvent etre utilises pour acquerir des donnees GPS d'autobus chaque seconde. Dans cet article, un modele analytique est propose dans le but de determiner les parametres de coordination des signaux pour la priorite des autobus le long d'une artere en se basant sur les donnees GPS de telephones mobiles. Premierement, les indicateurs d'evaluation des priorites pour les autobus sont etablis a l'aide des donnees GPS d'autobus qui sont acquises par les telephones mobiles. Deuxiemement, les parametres de synchronisation des signaux de l'artere sont optimises, et un plan de synchronisation preliminaire est elabore en evaluant de petits changements dans le plan. Enfin, le plan final correspondant est elabore a l'aide du logiciel de micro-simulation VISSIM. La faisabilite du modele analytique est verifiee en simulant une artere reelle dans la ville de Fuzhou, en Chine. [Traduit par la Redaction] Mots-cles: priorite des signaux d'autobus, modelisation, synchronisation des signaux, donnees GPS des telephones mobiles, micro-simulation., Introduction With the rapid development of urbanization and the increasing demand of automobile usage, traffic congestion increasingly grows in most cities. Public transport has the advantages of less energy consumption, [...]