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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 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]

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, [...]

Root biomass and length growth, functional traits, and their responses to soil nutrient availability are crucial for resource acquisition under environmental change. Previous studies have focused on the response of root morphological, architectural, and chemical traits to fertilization, while less attention has been given to root biomass and length growth, as well as mycorrhizal symbiosis, impeding a full understanding of root resource acquisition strategies. Here, using a nutrient addition experiment (control, inorganic, and organic nutrients), we explored the responses of function-based root (absorptive fine roots [AFRs] versus transport fine roots [TFRs]) growth, functional traits (morphological, architectural, and chemical traits), and mycorrhizal colonization of C. lanceolat and Q. acutissim, which are the dominant tree species in subtropical China. The results showed that the fine root biomass and total root length of AFRs for both tree species basically decreased significantly after nutrient addition, but TFRs responded less sensitively than AFRs. Nutrient addition significantly increased the mycorrhizal colonization rate in C. lanceolata but decreased it in Q. acutissima. The diameter of AFRs for C. lanceolata increased significantly, while the branch ratio and branch intensity decreased significantly in both inorganic nutrients (NPK) and organic nutrients (F); however, the opposite response pattern occurred for Q. acutissima. Fine root biomass, total root length, and root nutrient concentration exhibited the most plastic responses to changes in nutrient availability. The magnitude of the plastic response of fine root traits was slightly higher in the NPK treatment than in the F treatment. Our findings suggest that the responses of fine root traits and mycorrhizal fungi to nutrient addition were species-specific: C. lanceolata depended on mycorrhizal fungi for resource acquisition, while Q. acutissima could acquire soil nutrient resources by increasing root branching. The contrasting nutrient acquisition strategies between tree species may facilitate plant species coexistence and distribution under soil nutrient change. Fine root biomass and total root length emerged as more pivotal indicators for nutrient acquisition strategies compared to morphological traits. [ABSTRACT FROM AUTHOR]