In the journal-bearing system, the journal inevitably moves along the bearing axis, and the axial movement of journal may affect the performance of misaligned journal bearing. In this article, a ...numerical model for the thermohydrodynamic lubrication of bearing considering the axial movement of journal is established, and based on which a comprehensive analysis on the performance of misaligned journal bearing is conducted by solving the generalized Reynolds equation, heat conduction equation and energy equation. The results show that axial movement of misaligned journal has more obvious influence on the bearing lubrication characteristics at the lower speed, larger inclination angle and eccentricity. The impact of axial movement on the bearing lubrication performance is greatly affected by the thermal effect and surface roughness.
•A numerical model of thermohydrodynamic lubrication considering the axial movement of misaligned journal which moves along the bearing axis is built.•When the axial movement of misaligned journal takes place, the bearing lubrication performance will change significantly.•The impact of axial movement on the bearing lubrication performance is greatly affected by the thermal effect and surface roughness.
To improve the recognition of female images in Qing Dynasty literature, this paper designs a multivariate nonlinear-based image dynamic programming model. Data-driven typical correlation analysis is ...used to extract the key controllable variables with the strongest correlation with female image features and use them as input variables for modeling so as to make the maximum correlation between different image features and improve the modeling efficiency. The nonlinear spatial state model is established by using the subspace identification method, and the female image planning model is substituted into the multivariate nonlinear analysis, and the parameters of the nonlinear fitting function about the image planning can be obtained. The simulation analysis of the image dynamic planning model based on multivariate nonlinearity is carried out, and the results show that the average annual failure time of the model designed in this paper is 12.6 hours, and the classification accuracy in female image classification is 96.3%, and the classification time is stable at 1.162 s. The results show that the multivariate nonlinear features of the model can carry out dynamic planning of female images in Qing dynasty literature and improve the classification of image feature recognition.
Tourism is one of the largest service industries and a popular leisure activity participated by people with friends or family. A significant problem faced by the tourists is how to plan sequences of ...points of interest (POIs) that maintain a balance between the group preferences and the given temporal and spatial constraints. Most traditional group itinerary recommendation methods adopt predefined preference aggregate strategies without considering the group members’ distinctive characteristics and inner relations. Besides, POI textual information is beneficial to capture overall group preferences but is rarely considered. With these concerns in mind, this paper proposes an AMT-IRE (short for Attentive Multi-Task learning-based group Itinerary REcommendation) framework, which can dynamically learn the inner relations between group members and obtain consensus group preferences via the attention mechanism. Meanwhile, AMT-IRE integrates POI categories and POI textual information via another attention network. Finally, the group preferences are used in a variant of the orienteering problem to recommend group itineraries. Extensive experiments on six datasets validate the effectiveness of AMT-IRE.
To elucidate the molecular mechanisms governing the effect of Tounongsan decoction (, TNS) on the pyogenic liver abscess.
Based on oral bioavailability and drug-likeness, the main active components ...of TNS were screened using the Traditional Chinese Medicine Systems Pharmacology platform. The GeneCard and UniProt databases were used to establish a database of pyogenic liver abscess targets. The interactive network map of drug-ingredients-target-disease was constructed using Cytoscape software (Version 3.7.2). A protein-protein interaction network was constructed using the STRING database, and the related protein interaction relationships were analyzed. biological process of gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed for the core targets. Finally, a clinical trial was performed to verify the reliability of the network pharmacology.
Forty active components of TNS decoction were obtained, and 61 potential targets and 11 proteins were identified. Pathways involved in the treatment of pyogenic liver abscess include the phosphatidylinositide 3-kinases-protein kinase B (PI3K-AKT), advanced glycation end products-receptor for advanced glycation end products (AGE-RAGE), and tumor necrosis factor (TNF) signaling pathways. The results of network pharmacology analysis combined with clinical trials validated that TNS decoction could alleviate the inflammatory response of pyogenic liver abscesses by decreasing interleukin 6 (IL-6) levels.
TNS decoction has the characteristics of being multi-system, multi-component, and multi-target. Active ingredients in TNS, such as quercetin, kaempferol, fisetin, and β-sitosterol, have strong potential to be candidate drugs for treating pyogenic liver abscesses. The possible mechanism of TSN decoction includes regulating immune and inflammatory responses and reducing IL-6 production to control inflammatory development.
Degradation of poly (butylene succinate-co-terephthalate) (PBST) mulch film in the vast cotton field in the dry and windy plain has been studied. The films within 3 months' use which were above the ...soil and far away from the plant were selected collected as they were under closely identical outdoor degradation conditions. In macro mechanical properties, the quick decay of the ductility was the most obvious change of the mulch film in outdoor use. The elongation at break in transverse direction (TD) decreased faster than that in machine direction (MD). From micro view, chemical groups are almost retained within 3 months, while three kinds of changes in the polymer chain have been observed: (a) most additives are lost after 1 month's use; (b) chain slightly hydrolysis, of which far less than 1 break per chain occurs at the end of the 3rd month; (c) chain crosslinks, of which there are ∼1.3, 4.1 and 5.2 crosslink points per chain in average after 1, 2 and 3 months' use. The chain crosslink of the PBST is considered to be the main reason for the big decrease of the mechanical property, especially the ductility of the film, and then the main reason for the large-scale breakage of the film during 1∼2 months in Xinjiang. UV screening agent which has a strong adhesion to the polymer should be considered to solve the mulch film problem in the dry and windy plain.
•Accurate ductility decay of the muddy mulch film is got.•Most additives are lost at the time scale of ∼1 month.•Chains hydrolyze slightly, far less than 1 break per chain at the 3rd month.•Number of crosslink are ∼1.3, 4.1 and 5.2 points per chain after 1, 2 and 3 months.•Crosslink is the crucial factor for mulch film problem.
The generalized turbulent lubrication equation for isotropic rough surface bearings is presented by integrating the Hashimoto turbulent lubrication model and the Patir-Cheng laminar flow lubrication ...model. The finite difference method is used to solve the generalized turbulent lubrication equation and energy equation. And the variations for turbulent lubrication performance of journal bearing with the nominal eccentricity ratio and nominal average Reynolds number are obtained under the influence of surface roughness and journal misalignment. As the dimensionless surface roughness height of the bearing and the journal increases or the degree of misalignment increases, the dimensionless maximum film pressure, dimensionless load capacity and dimensionless misalignment moment of the bearing increases. The research of journal misalignment, thermal effect, and surface roughness is needed.
·The generalized turbulent lubrication equation considering surface roughness is proposed.·Surface roughness changes the performance of the journal bearing significantly.·Journal misalignment has a significant influence on the performance of journal bearing.
As an e-commerce feature, the recommender system can enhance the consumer shopping experience and create huge benefits for businesses. The e-tourism has become one of the largest service industries ...with the application and popularity of recommender systems. Many studies have confirmed that the travel product recommendation is widely different from traditional recommendations. Due to the financial and time costs, travel products are usually browsed and purchased relatively infrequently compared with other traditional products (e.g., books, movies and food). In addition, choosing the appropriate travel product will be influenced by many factors, such as departure, destination and price. To tackle this challenging problem, we propose a MV-GAN (short for Multi-View Graph Attention Network for travel recommendation) model. It enriches user and product semantics through both metapath-guided neighbors aggregation and multi-view fusion in heterogeneous travel product recommendation graph. In particular, we design node-level and path-level attention networks for learning user and product representations from every single view. To collaboratively integrate multiple types of relationships in different views, a view-level attention mechanism is proposed to aggregate the node representations and obtain global user and product representations. We evaluate the proposed method on a public dataset and a dataset constructed from a large tourism e-commerce website in China. Extensive experiments not only validate the effectiveness of MV-GAN, but also show its potentially good interpretability.
•We propose a graph neural network-based model for the travel recommendation.•User and item representations are learned in multi-view graph embedding networks.•An attention network is designed to integrating the user and product information.
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