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This study presents an innovative electrostatic spray flame synthesis (ESFS) reactor that combines the advantages of electrostatic spray and flame synthesis for precise spray control and efficient single-step continuous synthesis. To overcome the limitations of conventional ESFS systems, which often suffer from low atomized precursor flux, we successfully demonstrated a high-flux disk electrostatic atomizer coupled low-swirl flame reactor, achieving a precursor flux of up to 30 ml/h about 30 times higher than that of typical ESFS devices. The atomized precursor being rapidly carried away from the burner is undergoing high-temperature pyrolysis and particle formation through lifted premixed turbulent flames. The ESFS system provides extensive control over parameters such as flame temperature, equivalence ratio, residence time, initial droplet sizes, and precursor concentrations. For illustrative purposes, the ESFS system was utilized to synthesize silica nanoparticles, demonstrating the capability of synthesizing nanoparticles with various properties. By manipulating the collection position and height, the particle size has made a substantial leap from the nanoscale to the micrometer level. This remarkable achievement underscores the system's enormous potential for precise particle size regulation and one-step synthesis of complex structured thin films. [ABSTRACT FROM AUTHOR]

Flame spread over discrete fuels is a typical phenomenon in fire scenes. Experimental and theoretical research on flame spread over discrete thermally thin fuels separated by air gaps with different inclination angles was conducted in the present study. Experiments with six inclination angles ranging from 0° to 85° and various fuel coverage rates from 0.421 to 1 were designed. The flame spread behavior, the characteristic flame size, and the flame spread rate were analyzed. The results show that the flow pattern, stability, and flame size exhibit different characteristics with different inclination angles and gap sizes. As the inclination angle increases, particularly with smaller gaps, turbulent and oscillating flames are observed, while larger gap sizes promote flame stability. The mechanism of flame propagation across the gap depends on the interplay between the flame jump effect and heat transfer, which evolves with gap size. Average flame height, average flame width, and flame spread rate initially increase and then decline with the increase in fuel coverage, peaking at fuel coverage rates between 0.93 and 0.571 for different inclination angles. A theoretical model is proposed to predict the flame spread rate and the variation in the flame spread rate with inclination angle and fuel coverage. Furthermore, the map determined by inclination angle and fuel coverage is partitioned into distinct regions, comprising the accelerated flame spread region, the flame spread weakening region, and the failed flame spread region. These findings provide valuable insights into flame spread dynamics over discrete thermally thin fuels under diverse conditions. [ABSTRACT FROM AUTHOR]

This paper focuses on Hongcun in Anhui Province, using comments data of ctrip.com, ly.com and qunar.com as a samples, and makes a systematic analysis of Hongcun's tourism image through Python software. The study finds that the dimension of Hongcun image perception includes tourism attraction, tourism service, tourism environment and tourism atmosphere. The perception curve of tourism images of Hongcun presents the distribution characteristics of power functions, with obvious "long tail" distribution.Tourists have higher evaluation of Natural scenery and historical features,and lower evaluation for over-commercialization,single tourism items and disordered management in tourism-peak season. Accordingly, it is necessary to establish the concept of protective development and protect the authenticity of Hongcun . At the same time, it is necessary to enrich the cultural connotation of tourism products and enhance the experience of tourists.

At present, with the development of rural tourism in full swing, the protection and renewal of rural eco-tourism landscape has become an important part of rural landscape planning and construction in the new era. From the perspective of tourists’ perception, this paper takes Longji Terrace Scenic Spot in Guilin, Guangxi as an example, and uses ROST CM6 software analyzes tourists’ landscape perception and characteristics from high-frequency vocabulary, semantic network and other aspects. Based on this, it finds out the existing problems in the current landscape planning of rural eco-tourism area, and puts forward planning suggestions. The purpose is to provide reference for the rational planning and allocation of rural tourism landscape, to improve the quality of life of rural residents, and to promote the construction of beautiful villages. The results show that: (1) high-frequency words indicate that tourists focus on human landscape and natural landscape; (2) the semantic network matrix takes “landscape”, “Jiulong Wuhu”, “Longji Terrace”, “Jinkeng Dazhai” as the core; (3) tourists’ perception of the landscape of Longji Terrace Scenic Spot focuses on terrace scenery, ethnic customs and specialties, mountain climbing ways and other aspects; (4) tourists’ emotional evaluation of Longji Terrace Scenic Spot is mainly positive emotion, and relatively less negative emotion.

Analyzing the factors that affect tourist satisfaction can guide the sustainable development of tourist destination to a certain extent. In order to study the influence of Landscape Gene on the tourist satisfaction, the model of the structural equation was constructed by constructing the identification system and constructing the model of the structural equation. The results show that the characteristics of the building and the characteristics of the folk custom are positively influenced. The characteristics of the faith have a negative effect on the satisfaction of the tourists, and the correlation coefficient is prominent. The characteristics of the environment have a negative impact on tourist satisfaction. The effect of the folkcustom character on tourist satisfaction is the most significant.

This article taking the travel notes of the ant mafengwo.com and Ctrip.com as a sample, using the content analysis method and ROST CM6 to analyze the visitors’ perception of the Guilin tourism destination image, through the analysis of the high-frequency vocabulary and the semantics of the network notes, and the spindle coding, From eight categories of humanistic attraction, natural attraction, tourism transportation, special food, accommodation conditions, overall impression, tourism consumption and service level, It is found that the tourists’ perception of Guilin tends to be positive. The basic information characteristics, cognitive image, emotional image and willingness to travel are comprehensively explored. The image of Guilin is proposed from the improvement of hardware elements, the innovation of tourism image marketing methods and the improvement of software image elements.

This paper presents a numerical model that investigates the characteristics of flow, heat, and mass transfer on downward flame propagation in the discontinuous region of solid fuel. Simulations were carried out for various discontinuous distances to analyze the morphology of the flame front and the competition between the "jump" of flame spread and heat transfer from the flame to the unburned area. The results demonstrate that there is a "jump" in the flame propagation in the discontinuous zone, with the flame front exhibiting a defined "acute angle" that undergoes a process from large to small during the flame spreading in the discontinuous area and deflects towards the discontinuous area of the material. The temperature in the discontinuous zone reaches a peak, and the average flame spread rate initially increases and then decreases with the increase of discontinuity distance until the flame spread stops. The study provides valuable insights into the growth and development of fires involving discretely distributed combustible materials. [ABSTRACT FROM AUTHOR]

Occurrence of wildfires is common in all continents with wildland vegetation. In general, complete observation of fire perimeter is carried out for a data assimilation framework. Moreover, the common practice assumes that observation data have a constant error. However, the airborne or spaceborne observations may be incomplete and/or have the spatial variations of error variance due to instrument failures or the presence of fire-induced smoke plume or cloud cover. To overcome these issues, a vertex weight was introduced for revising the nudge term to offset the limitation of the traditional implementation of ensemble transform Kalman filter (ETKF) in this study. Herein, the extent of nudging the prediction simulations toward the observation in the vertexes, where observation data were missing or exhibited lower fidelity, was adjusted. The merits of the flexible spatially distributed state estimation approach were demonstrated through a series of observing system simulation experiments (OSSEs). The performance of the vertex weight-based ETKF (VWETKF) was compared with that of the ETKF. The results have showed that the proposed VWETKF scheme is superior to ETKF and leads to improvement of the prediction accuracy. [ABSTRACT FROM AUTHOR]

This paper examines the relationships between motivation to visit, performance evaluation, satisfaction, and behavioural intentions for tourists experiencing ‘Impressions of Liusanjie’, an iconic, outdoor, theatrical performance in Guilin, China. The study finds that motivation does not affect satisfaction directly but that performance evaluation is an intervening variable between motivation and satisfaction. It also finds that experiential evaluation of the theatrical performance has more effect on satisfaction than evaluation of technical and functional attributes. Tourists were surveyed after the performance and the results analysed using cluster, correlation analysis and structural equation modelling (SEM). The first two techniques were used to identify existing relationships amongst the study variables. SEM was applied to determine if a causal relationship existed and, if so, their strength. This research provides a contribution to the understanding of tourist motivation, theatrical performance evaluation, satisfaction, and behavioural intentions. [ABSTRACT FROM AUTHOR]

This research presents an in-depth examination of the combustion characteristics of flame-retardant electrical wires, contrasting behavior with non-flame-retardant counterparts under jet flame heating. The study systematically investigates the pyrolysis process, ignition patterns, charring behavior, and the development of secondary flames in wires with different core diameters and insulation materials. Findings indicate the heightened susceptibility of thinner wires to rapid heating, pyrolysis and charring, leading to faster ignition and more intense secondary flame development. This insight is crucial for tailoring flame-retardant formulations to specific wire dimensions. The research also delves into the thermal dynamics within the wires, highlighting how the core diameter influences axial heat conduction and, consequently, the overall flame spread behavior and pyrolysis rate. A critical discovery is the relationship between heating duration and flame sustainability, establishing a specific range of heating times for sustaining secondary flames in flame-retardant wires. Theoretical models used in the study explained the critical heat flux heating time for wire ignition, offering insights into improved fire prevention strategies, particularly in prolonged heat exposure scenarios. These findings not only advance our understanding of flame-retardant wire behavior under fire conditions but also provide guidance for selecting and using electrical wires, thereby optimizing fire safety in diverse applications. • Pyrolysis, ignition, charring, and secondary flames in Flame-Retardant wire were investigated. • Finer wires are more sensitive to rapid heating, pyrolysis, and charring, leading to stronger secondary flame. • The specific range of heating time for sustaining secondary flames in flame-retardant wires was established. • Theoretical model explained the critical heat flux heating time for wire ignition. [ABSTRACT FROM AUTHOR]

With more and more large-scale activities conducted in the cities, the issue how to evaluate risk in activities has attracted a lot of researchers to investigate. Bidirectional flow can be commonly observed in mass gathering events, therefore it is of great importance to gain deeper insights into this kind of movement. In this manuscript, three kinds of entropy are introduced and used in order to measure the disorder and risk of bidirectional movement, namely position entropy, angle entropy and speed entropy. Larger entropy means more uncertainty and risk in the system. Entropy is applied in two counter-flow experiments in order to describe the level of randomness. It is found when the number of lanes transits from 4 to 3, there is a sharp increase in respect of entropy because occupants compete for the space to move forward. In order to testify the effect of position entropy, another scenario is calculated and small position entropy means steady bidirectional movement, which is in accordance with the realistic movement in experiment. The speed entropy is measured and similar trend can be observed by comparing with speed variance proposed by previous researchers. Furthermore, angle entropy is also investigated and relation between angle entropy and density is obtained. The proposed entropy can help quantify randomness of counter-flow movement and be beneficial forfor the managers to better deal with potential abnormal activities. [ABSTRACT FROM AUTHOR]