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Spatial information is a critical feature in a large number of application domains. Spatial information, however, is often not crisp but with the nature of imprecision and fuzziness. As the increasing requirements of spatial applications, there emerges many challenges regarding to the representation and reasoning of spatial knowledge. Description logic (DL) is a logical basis for representing knowledge and realizing reasoning tasks in the Semantic Web. Therefore, how to extend DL to achieve the goal of representing and reasoning fuzzy spatial knowledge needs to be settled. In this work, we study a fuzzy spatial extension of the well known fuzzy ALCDL to reason fuzzy spatial knowledge. First, we construct a fuzzy spatial concrete domain Swhich is comprised of fuzzy spatial regions and fuzzy RCC relationships. More importantly, we give the admissibility proof of fuzzy spatial concrete domain S. Then we extend fuzzy ALCwith an admissible fuzzy spatial concrete domain Sand present a fuzzy spatial description logic f-ALC(S). Finally, we address a decision procedure for f-ALC(S)ABox consistency problem. Also, we show that the decision procedure is correct and the consistency problem for f-ALC(S)is decidable in PSPACE-complete.

Filament winding (FW) technology is an important molding technology to obtain high-performance filament-wound composites. However, current methods for evaluating the mechanical properties of plant fibers for FW are directly borrowed from those of synthetic fibers, which may not be appropriate due to the heterogeneity of plant fibers and the unique twisting structure of plant fiber yarns. Herein, jute yarn Naval Ordnance Laboratory (JY-NOL) composites were prepared by FW technology using jute yarns (JYs) and epoxy resin (EP) to propose suitable methods for evaluating mechanical properties. Moreover, the improvement mechanism of mechanical properties of JY-NOL composites was elucidated by exploring the effects of the impregnation method, resin mass fraction and winding tension on the mechanical properties of JY-NOL composites. The results showed that the methods for evaluating the mechanical properties of JY-NOL composites with different JY specifications based on a five-layer winding structure were more scientific and reliable than the methods for evaluating the mechanical properties based on a 3-mm thickness. With the increase in the metric count and the decrease in the number of yarn strands of JYs, the glue loading of JYs gradually increased, and JYs had a unique twisting structure, making it difficult for the interiors of JYs to be impregnated with EP. Therefore, the winding parameters related to the impregnation method, resin mass fraction and winding tension were optimized, aiming at improving the impregnation effect of EP on JYs and reducing the voids in JY-NOL composites, thus strengthening the mechanical properties of JY-NOL composites.

This study presents the fire performance of typical components of wood structure buildings. The wooden beams and floor slabs, quite common in wood structure buildings, were burned with different fire exposure times by a pool fire source. Then, the surface temperature evolution and the charring rate were recorded and analyzed. The results show that the flashover and re-ignition phenomenon occurred in all wood materials under the burning pool fires. The glulam beam cross-section was U-shaped, and the maximum charring rates of glulam beam, cross-laminated timber floor, and cross-laminated timber partition board were 0.833 mm/min, 1.538 mm/min, and 0.435 mm/min, respectively. It can be seen that the combustion behavior time of specimens with different cross-section thicknesses is different. If the thickness of the specimens is appropriately increased, their combustion behavior time can be significantly improved.

Advances in methacrylates have continued to appear because of the increased use of thermoplastics and thermosets, which require adhesives that offer speed, flexibility, toughness and primerless bonding. Original methacrylate adhesives [...]

A single-dynamic-gain scaling output feedback control method is proposed with the novelty lying in (i) constructing a couple of observer-controller with the modification of scaling-gain exponent and (ii) introducing time-varying coupled matrix inequalities to deal with the large measurement uncertainty. By combining with the non-identification adaptive mechanism, the proposed dynamic output feedback controller is applicable to a class of nonlinear systems in the absence of the knowledge of upper bounds of unknown parameters in the nonlinearities and output equation, and global state asymptotical regulation is achieved with a bounded adaptive gain. Especially, the uncertain parameters in the nonlinearities and (non-differentiable) output function are both handled by a single-scaling gain. Moreover, the control method of this paper is non-backstepping and all design parameters are easy to obtain. [ABSTRACT FROM AUTHOR]

AbstractWildfires not only directly affect ecology but also have a huge impact on social and economic stability. Enhancing the understanding of wildfire influences can guide the design of targeted strategies in mitigation plans and adaptation strategies. Here, we explored the spatial-temporal characteristics of wildfires in the Beijing-Tianjin-Hebei region of China and the mechanisms of the effect of potential influencing factors on wildfire occurrence based on 2014–2020 wildfire data. The results show that wildfires mainly occur in spring and winter and decrease yearly. Among all the considered influencing factors, the occurrence of wildfire is most significantly affected by the temperature vegetation dry index (TVDI) and is also greatly affected by population and economy. Through interaction detection, it was found that the normalized difference vegetation index (NDVI) greatly interfered with wildfires. The high occurrence risk of wildfire was distributed in a blocky pattern in the middle and east of the study area. In addition, we also found a positive spatial correlation between the high wildland-urban interface (WUI) presence and high wildfire occurrence. These findings have improved our understanding of the impact of multiple influencing factors on wildfires and are supposed to facilitate the development of wildfire management strategies.

Ontology, as a formal representation method of domain knowledge, plays a particular important key role in semantic web. How to construct ontologies has become a key technology in the semantic web, especially constructing ontologies from existing domain knowledge. Currently, Petri nets have been a mathematical modeling tool, and have been widely studied and successfully applied in modeling of software engineering, database and artificial intelligence. In particular, PNML (Petri Net Markup Language) language has been a part of ISO/IEC Petri nets standard for representing and exchanging data on Petri nets. Therefore, how to construct ontologies from PNML model of Petri nets needs to be investigated. In this article, the authors investigate a method for automatic construction of web ontology language (OWL) ontologies from PNML of Petri nets. Firstly, this paper gives a formal definition and the semantics of PNML models of Petri nets. On this basis, a formal approach for constructing OWL ontologies from PNML model of Petri nets is proposed, i.e., this paper transforms Petri nets (including PNML model and PNML document of the Petri nets) into OWL ontologies at both structure and instance levels. Furthermore, the correctness of the transformation is proved. Finally, a prototype construction tool called PN2OWL is developed to transform Petri nets models into OWL ontologies automatically.

Polyphenols are the main active components of the anti-inflammatory compounds in dandelion, and chlorogenic acid (CGA) is one of the primary polyphenols. However, the molecular mechanism underlying the transcriptional regulation of CGA biosynthesis remains unclear. Hydroxycinnamoyl-CoA:quinate hydroxycinnamoyl transferase (HQT2) is the last rate-limiting enzyme in chlorogenic acid biosynthesis in Taraxacum antungense. Therefore, using the TaHQT2gene promoter as a probe, a yeast one-hybrid library was performed, and a basic helix-loop-helix (bHLH) transcription factor, TabHLH1, was identified that shared substantial homology with Gynura bicolorDC bHLH1. The TabHLH1transcript was highly induced by salt stress, and the TabHLH1 protein was localized in the nucleus. CGA and luteolin concentrations in TabHLH1-overexpression transgenic lines were significantly higher than those in the wild type, while CGA and luteolin concentrations in TabHLH1-RNA interference (RNAi) transgenic lines were significantly lower. Quantitative real-time polymerase chain reaction demonstrated that overexpression and RNAi of TabHLH1in T. antungensesignificantly affected CGA and luteolin concentrations by upregulating or downregulating CGA and luteolin biosynthesis pathway genes, especially TaHQT2, 4-coumarate-CoA ligase (Ta4CL), chalcone isomerase (TaCHI), and flavonoid-3′-hydroxylase (TaF3′H). Dual-luciferase, yeast one-hybrid, and electrophoretic mobility shift assays indicated that TabHLH1 directly bound to the bHLH-binding motifs of proTaHQT2and proTa4CL. This study suggests that TabHLH1 participates in the regulatory network of CGA and luteolin biosynthesis in T. antungenseand might be useful for metabolic engineering to promote plant polyphenol biosynthesis.