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The influence of road surface temperature (RST) on vehicles is becoming more and more obvious. Accurate predication of RST is distinctly meaningful. At present, however, the prediction accuracy of RST is not satisfied with physical methods or statistical learning methods. To find an effective prediction method, this paper selects five representative algorithms to predict the road surface temperature separately.

Multiple linear regressions, least absolute shrinkage and selection operator, random forest and gradient boosting regression tree (GBRT) and neural network are chosen to be representative predictors.

The experimental results show that for temperature data set of this experiment, the prediction effect of GBRT in the ensemble algorithm is the best compared with the other four algorithms.

This paper compares different kinds of machine learning algorithms, observes the road surface temperature data from different angles, and finds the most suitable prediction method.

This paper aims to establish the relationship between crosswind speed and pantograph-catenary lateral deviation, as well as quantify the influence of crosswind speed and rod size uncertainty on pantograph-catenary contact reliability.

The closed vector method is used to establish the pantograph-catenary kinematics formula. A new prediction model is proposed by using the bird swarm algorithm to optimize the grey model. The lateral deviation of the pantograph and catenary is predicted via the new model. Then the relationship between the effective length of the rod and operating mileage is inferred by combining the effective length theory with the Gamma process, as well as the pantograph-catenary contact reliability model is established according to reliability theory.

The results obtained show the impacts of uncertainty design parameters of pantograph rods on pantograph-catenary contact reliability index, and the results at crosswind speed of 0 ms⁻¹ and 5 ms⁻¹ are 5.0630 and 4.1442, respectively. The reliability decreases with the increasing crosswind speed, and can be greater than the reliability calculated for rod size degradation due to long-term use.

Most preceding works on pantograph-catenary contact reliability were based on principles of dynamics, without considering the pantograph-catenary relative motion. This research reveals the law of pantograph-catenary relative motion for uncertainty design parameters and crosswind, and quantifies the reliability from the angle of kinematics.

This paper aims to comprehensively clarify the research status of thermal transport of supercritical aviation kerosene, with particular interests in the effect of cracking on heat transfer.

A brief review of current research on supercritical aviation kerosene is presented in views of the surrogate model of hydrocarbon fuels, chemical cracking mechanism of hydrocarbon fuels, thermo-physical properties of hydrocarbon fuels, turbulence models, flow characteristics and thermal performances, which indicates that more efforts need to be directed into these topics. Therefore, supercritical thermal transport of n-decane is then computationally investigated in the condition of thermal pyrolysis, while the ASPEN HYSYS gives the properties of n-decane and pyrolysis products. In addition, the one-step chemical cracking mechanism and SST k-ω turbulence model are applied with relatively high precision.

The existing surrogate models of aviation kerosene are limited to a specific scope of application and their thermo-physical properties deviate from the experimental data. The turbulence models used to implement numerical simulation should be studied to further improve the prediction accuracy. The thermal-induced acceleration is driven by the drastic density change, which is caused by the production of small molecules. The wall temperature of the combustion chamber can be effectively reduced by this behavior, i.e. the phenomenon of heat transfer deterioration can be attenuated or suppressed by thermal pyrolysis.

The issues in numerical studies of supercritical aviation kerosene are clearly revealed, and the conjugation mechanism between thermal pyrolysis and convective heat transfer is initially presented.

This paper aims to elucidate how humorous prompts affect tourists’ heritage responsible behaviors (THRBs).

Three scenario-based experiments were conducted through Credamo (an online survey platform). Studies 1 and 2 used a single-factor (language style: humorous vs serious) between-subject design to test the direct and indirect effects of humorous prompts. Study 3 used a 2 (environmental quality: high vs low) × 2 (language style: humorous vs serious) between-subject design to further reveal the boundary condition (environmental quality) of the humor effect.

The results revealed that humorous (vs serious) prompts better persuade tourists to engage in heritage responsible behaviors (HRBs). Content liking mediates the relationship between humorous prompts and THRBs. Moreover, environmental quality significantly moderates the effect of humorous prompts on THRBs, whereby the persuasive effect of humorous prompts is greater in high environmental quality conditions than in low environmental quality conditions.

Destination management organizations can use humor to reduce tourists’ reactance against prompts for behavioral persuasion. Moreover, it is also important to adapt humorous prompts to changes in environmental quality in a timely manner.

Based on psychological reactance theory, the research confirmed the dominant effect of humorous prompts by using content liking as a mediating variable, providing a new research perspective for research on the regulation of THRBs. Moreover, the authors clarified a boundary condition for the persuasiveness of humorous prompts, which helps reinforce the comprehension of humor persuasion.

本研究旨在厘清幽默提示语如何影响游客遗产责任行为的差异效应与过程机制。

本研究利用见数平台开展了三个情景实验。实验1与实验2采用单因素（语言风格：幽默 vs. 严肃）组间实验设计, 验证了幽默提示语对遗产责任行为的直接与间接效应。实验3采用2（语言风格：幽默 vs. 严肃）×2（环境质量：高 vs. 低）组间实验设计进一步揭示环境质量对幽默提示语效果的调节效应。

相较于严肃提示语, 幽默提示语可更好地说服游客产生遗产责任行为。内容喜爱在幽默提示语与遗产责任行为过程中发挥完全中介作用。此外, 环境质量调节了幽默提示语对遗产责任行为的影响, 即幽默提示语（较严肃提示语）仅在环境质量较高的遗产地中具备优势。

遗产地管理组织可使用幽默来降低游客对提示语的心理逆反程度, 从而达到行为说服的目的。与此同时, 管理者也要根据目的地环境质量及时调整幽默提示语的使用策略。

基于心理逆反理论, 本研究以内容喜爱为中介变量, 证实了幽默提示语的优势说服作用, 为游客遗产责任行为管理的相关研究提供了一个新的理论视角。同时, 本研究厘清了幽默提示语在遗产旅游地中的应用边界, 并强化了对幽默说服的理解。

Esta investigación pretende aclarar cómo afecta el humor al efecto persuasivo de la señalización sobre el comportamiento responsable de los turistas respecto al patrimonio.

Se realizaron tres experimentos basados en escenarios a través de Credamo (una plataforma de encuestas en línea). En los estudios 1 y 2 se utilizó un diseño entre sujetos de un solo factor (estilo de lenguaje: humorístico frente a serio) para comprobar los efectos directos e indirectos de los señalización humorísticos. El estudio 3 utilizó un diseño entre sujetos de 2 (calidad del entorno: alta frente a baja) × 2 (estilo lingüístico: humorístico frente a serio) para revelar con más detalle la condición límite (calidad del entorno) del efecto del humor.

Los resultados revelaron que las señalización humorísticas (frente a las serias) persuaden mejor a los turistas a participar en las HRB. El gusto por el contenido influye en la relación entre los señalización humorísticos y las HRB. Además, la calidad del entorno modera de forma significativa el efecto de los señalización humorísticos sobre los THRB, de modo que el efecto persuasivo de los señalización humorísticos es mayor en condiciones de alta calidad del entorno que en condiciones de baja calidad del entorno.

Las organizaciones de gestión de destinos pueden utilizar el humor para reducir la reacción de los turistas ante las señalización a la persuasión conductual. Además, también es importante adaptar oportunamente las señalización humorísticas a los cambios en la calidad del entorno.

Basándonos en la teoría de la reactancia psicológica, nuestra investigación confirmó el efecto dominante de las señalización humorísticas empleando el gusto por el contenido como variable mediadora, proporcionando una nueva perspectiva para la investigación sobre la regulación de las THRB. Además, aclaramos una condición límite para la persuasión de los señalización humorísticos, lo que ayuda a reforzar la comprensión de la persuasión humorística.

Virtual tourism has become popular in recent years. However, there is still a research gap on virtual tourist motivation. This study aims to identify virtual tourist motivation and explore the relationship between virtual tourism and on-site tourism.

This research identifies virtual tourist motivation based on Means-end chain (MEC) theory. Laddering interviews with 32 respondents were conducted to construct a hierarchical value map. Additionally, a motivation analysis of virtual tourism and on-site tourism was developed based on a review of the relevant literature.

This exploratory study revealed 12 attributes, 9 results and 4 values that virtual tourists wish to achieve and identified 5 means-end chains where self-satisfaction is the most important value-led motivation. Compared with on-site tourism motivations, virtual tourism shows possibilities of replacing, complementing and extending on-site tourism under certain circumstances. However, it significantly depends on whether tourists are attracted by the technical characteristics, security and experience conditions of virtual tourism.

This study contributes to understanding virtual tourist motivation and offers motivation-based insights into the relationship between virtual and on-site tourism. Managerial implications on how to attract potential online tourists are also provided.

虚拟旅游在近些年逐渐受到欢迎。然而, 关于虚拟旅游动机的研究仍存在不足。本研究旨在识别虚拟旅游动机, 并探讨虚拟旅游与现实旅游之间的关系。

本研究基于方法-目的链（MEC）理论识别虚拟游客动机。通过对32名受访者进行阶梯式访谈, 以构建一个价值阶层图。此外, 本研究在回顾相关文献基础上, 对虚拟旅游和现实旅游的动机进行差异化比较分析。

这项探索性研究揭示了虚拟旅游游客希望实现的12个属性、9个结果和4个价值, 并确定了5条MEC, 其中自我满足是最重要的价值导向动机。通过与现实旅游动机比较, 研究发现虚拟旅游在一定条件下具有替代、补充和延伸现实旅游的可能性。然而, 这在很大程度上取决于游客是否被虚拟旅游的技术特点、安全性和体验等条件所吸引。

研究结果有助于进一步理解虚拟旅游动机, 并为虚拟旅游和现实旅游之间的关系提供基于动机的见解。重要的是, 研究还为如何吸引潜在虚拟游客提供管理启示。

El turismo virtual se ha popularizado en los últimos años. Sin embargo, aún existe un vacío en la investigación sobre la motivación del turista virtual. El estudio pretende identificar la motivación del turista virtual y explorar la relación entre el turismo virtual y el turismo in situ (real).

Esta investigación identifica la motivación del turista virtual basándose en la teoría de la cadena medio-fin (MEC). Se realizaron entrevistas escalonadas a 32 encuestados para construir un mapa jerárquico de valores. Además, se elaboró un análisis de la motivación del turismo virtual y del turismo presencial basado en una revisión de la bibliografía pertinente.

El estudio exploratorio reveló 12 atributos, 9 resultados y 4 valores que los turistas virtuales desean alcanzar e identificó 5 MEC en los que la autosatisfacción es la motivación basada en valores más importante. En comparación con las motivaciones del turismo in situ (real), el turismo virtual muestra posibilidades de sustituir, complementar y ampliar el turismo in situ (real) en determinadas circunstancias. Sin embargo, depende en gran medida de si los turistas se sienten atraídos por las características técnicas, la seguridad y las condiciones de experiencia del turismo virtual.

Este estudio contribuye a comprender la motivación del turista virtual y ofrece perspectivas basadas en la motivación sobre la relación entre el turismo virtual y el turismo in situ (real). También se ofrecen implicaciones para la gestión sobre cómo atraer a los turistas potenciales en línea.

Sensorless interior permanent magnet in-wheel motor (IPMIWM), as an exemplar of modular automation system, has attracted considerable interests in recent years. This paper aims to investigate a novel hybrid control approach for the sensorless IPMIWM from a cyber-physical systems (CPS) perspective.

The control approach is presented based on the hybrid dynamical theory. In the standstill-low (S-L) speed, the rotor position/speed signal is estimated by the method of the high frequency (HF) voltage signal injection. The least square support vector machine (LS-SVM) is used to acquire the rotor position/speed signal in medium-high (M-H) speed operation. Hybrid automata model of the IPMIWM is established due to its hybrid dynamic characteristics in wide speed range. A hybrid state observer (HSO), including a discrete state observer (DSO) and a continuous state observer (CSO), is designed for rotor position/speed estimation of the IPMIWM.

The hardware-in-the-loop testing based on dSPACE is carried out on the test bench. Experimental investigations demonstrate the hybrid control approach can not only identify the rotor position/speed signal with a certain load but also be able to reject the load disturbance. The reliability and the effectiveness of the proposed hybrid control approach were verified.

The proposed hybrid control approach for the sensorless IPMIWM promotes the deep combination and coordination of sensorless IPMIWM drive system. It also theoretically supports and extends the development of the hybrid control of the highly integrated modular automation system.

Continuous annealing (CA) units usually lack a physical shapemeter; consequently, real-time display and closed-loop control of the strip shape are impossible to achieve.

A shape model for the CA process is established in this study. Specifically, a virtual shapemeter and closed-loop control system based on the advanced parameter acquisition system and information transmission of CA units are developed in C++ programming language. This system realises real-time dynamic shape display, closed-loop control and shape prediction by collecting raw data of steel coils and parameters during CA.

Field test results show that the shape predicted by the virtual shapemeter coincides with the measured shape by over 90 per cent, which fully meets the precision requirement of industrial applications.

Moreover, shape quality is effectively improved without increasing hardware investments.

In recent years, electronic word-of-mouth (e-WOM) concerning travel products reflected in online review information has become an important reference for tourists to make their product purchase decisions, while for travel service providers (TSPs), monitoring and improving the e-WOM of their travel products is always an important task. Therefore, based on the online review information, how to capture e-WOM of travel products and find out specific ways to improve the e-WOM is a noteworthy research problem. The purpose of this paper is to develop a method for capturing and analyzing e-WOM toward travel products based on sentiment analysis and stochastic dominance.

Specifically, online review information of travel products is first crawled and preprocessed. Second, sentiment strengths of online review information toward travel products concerning each feature are judged. Then, the matrix of structured online review information toward travel products is formed. Further, the matrix of e-WOM comparisons between any two travel products is constructed, and e-WOM ranking concerning each travel product is determined. Finally, trade-off chart models are constructed to conduct the e-WOM improvement analyses concerning the travel products.

An empirical study based on the online review information toward six travel products crawled from the Tuniu.com website is given to illustrate the use of the proposed method.

The proposed method can not only realize the real-time e-WOM monitoring to travel products but also be useful for TSPs to improve the e-WOM of their travel products.

In this paper, with the goal of reducing the fuel consumption of UAV, the engine performance optimization is studied and on the basis of aircraft/engine integrated control, the minimum fuel consumption optimization method of engine given thrust is proposed. In the case of keeping the given thrust of the engine unchanged, the main fuel flow of the engine without being connected to the afterburner is optimally controlled so as to minimize the fuel consumption.

In this study, the reference model real-time optimization control method is adopted. The engine reference model uses a nonlinear real-time mathematical model of a certain engine component method. The quasi-Newton method is adopted in the optimization algorithm. According to the optimization variable nozzle area, the turbine drop-pressure ratio corresponding to the optimized nozzle area is calculated, which is superimposed with the difference of the drop-pressure ratio of the conventional control plan and output to the conventional nozzle controller of the engine. The nozzle area is controlled by the conventional nozzle controller.

The engine real-time minimum fuel consumption optimization control method studied in this study can significantly reduce the engine fuel consumption rate under a given thrust. At the work point, this is a low-altitude large Mach work point, which is relatively close to the edge of the flight envelope. Before turning on the optimization controller, the fuel consumption is 0.8124 kg/s. After turning on the optimization controller, you can see that the fuel supply has decreased by about 4%. At this time, the speed of the high-pressure rotor is about 94% and the temperature after the turbine can remain stable all the time.

The optimal control method of minimum fuel consumption for the given thrust of UAV is proposed in this paper and the optimal control is carried out for the nozzle area of the engine. At the same time, a method is proposed to indirectly control the nozzle area by changing the turbine pressure ratio. The relevant UAV and its power plant designers and developers may consider the results of this study to reach a feasible solution to reduce the fuel consumption of UAV.

Fuel consumption optimization can save fuel consumption during aircraft cruising, increase the economy of commercial aircraft and improve the combat radius of military aircraft. With the increasingly wide application of UAVs in military and civilian fields, the demand for energy-saving and emission reduction will promote the UAV industry to improve the awareness of environmental protection and reduce the cost of UAV use and operation.

The purpose of this paper is to numerically study the influence of wall conduction on the heat transfer of supercritical n-decane in the active regenerative cooling channels.

A horizontally placed rectangular pipe with a solid zone and another one without a solid zone were used. A drastic variation of thermo-physical properties was emphatically addressed. After the verification of mesh and turbulence models comparing with the experimental results, a mesh number of 4.5 M and the low Reynolds number SST k-ω turbulence model were chosen. The solution of the governing equations and the acquisition of the numerical results were executed by the commercial software FLUENT 2020 R1.

The numerical results indicate that there is a heat transfer deterioration (HTD) potential for the upper wall, lower wall and sidewall with the decrease of mass flux. Due to wall conduction, the distribution of the fluid temperature at spanwise-normal planes becomes uniform and this feature also takes advantage of the relatively uniform transverse velocity. For the streamwise-normal planes, the low fluid temperature appears close to the upper wall at the region near the sidewall and vice versa for the region near the centre. Undoubtedly, the secondary flow at the cross-section plays a crucial role in this process and the relatively cool mainstream is affected by the vortices.

This study warns that the wall conduction must be considered in the practical design and thermal optimization due to the sensibility of thermo-physical properties to the heat flux. The secondary flow caused by the buoyancy force (gravity) plays a significant role in the supercritical heat transfer and mixed convection heat transfer should be further studied.