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Plantar force is the interface pressure existing between the foot plantar surface and the shoe sole during static or dynamic gait. Plantar force derived from gait and posture plays a critical role for rehabilitation, footwear design, clinical diagnostics and sports activities, and so on. This paper aims to review plantar force measurement technologies based on piezoelectric materials, which can make the reader understand preliminary works systematically and provide convenience for researchers to further study.

The review introduces working principle of piezoelectric sensor, structures and hardware design of plantar force measurement systems based on piezoelectric materials. The structures of sensors in plantar force measurement systems can be divided into four kinds, including monolayered sensor, multilayered sensor, tri-axial sensor and other sensor. The previous studies about plantar force measurement system based on piezoelectric technology are reviewed in detail, and their characteristics and performances are compared.

A good deal of measurement technologies have been studied by researchers to detect and analyze the plantar force. Among these measurement technologies, taking advantage of easy fabrication and high sensitivity, piezoelectric sensor is an ideal candidate sensing element. However, the number and arrangement of the sensors will influence the characteristics and performances of plantar force measurement systems. Therefore, it is necessary to further study plantar force measurement system for better performances.

So far, many plantar force measurement systems have been proposed, and several reviews already introduced plantar force measurement systems in the aspect of types of pressure sensors, experimental setups for foot pressure measurement analysis and the technologies used in plantar shear stress measurements. However, this paper reviews plantar force measurement systems based on piezoelectric materials. The structures of piezoelectric sensors in the measurement systems are discussed. Hardware design applied to measurement system is summarized. Moreover, the main point of further study is presented in this paper.

Fluctuations in the tender price index have an adverse effect on the construction sector and the economy at large. This is largely due to the positive relationship that exists between the construction industry and economic growth. The consequences of these variations include cost overruns and schedule delays, among others. An accurate forecast of the tender price index is good for controlling the uncertainty associated with its variation. In the present study, the efficacy of using an adaptive neuro-fuzzy inference system (ANFIS) for tender price forecasting is investigated. In addition, the Box–Jenkins model, which is considered a benchmark technique, was used to evaluate the performance of the ANFIS model. The results demonstrate that the ANFIS model is superior to the Box–Jenkins model in terms of the accuracy and reliability of the forecast. The ANFIS could provide an accurate and reliable forecast of the tender price index in the medium term (i.e. over a three-year period). This chapter provides evidence of the advantages of applying nonlinear modelling techniques (such as the ANFIS) to tender price index forecasting. Although the proposed ANFIS model is applied to the tender price index in this study, it can also be applied to a wider range of problems in the field of construction engineering and management.

The purpose of this paper is to promote the corrosion resistance of the 5083-111H aluminum alloy by laser cleaning.

Laser with 2 ns pulse width was adopted in this project and the corrosion resistance of cleaned samples was tested by copper-accelerated salt spray (CASS). The surface morphology, elemental composition and distribution were then characterized by SEM. Moreover, surface morphology, elemental composition and distribution were also tested.

Results suggested a higher corrosion resistance was successfully obtained by laser cleaning. Compared with samples cleaned by 2000 grit sandpaper, mechanical cleaning resulted in a 53% larger height difference between the peak and valley. The content of the oxygen is 8.85% on the surface cleaned mechanically and the distribution is dependent on the distribution of aluminum whereas that of the laser cleaning sample is 24.41% and the distribution existed even in the Al-poor area.

In this project, the 2-ns laser cleaning was proved to have the capability to remove the oxide layer on the aluminum alloy surface while retaining an excellent corrosion resistance and smooth surface. Meanwhile, a thorough elemental distribution and smaller grain size lead to a smaller difference in elemental concentration. This retards the diffusion of oxygen into the substrate and hence increases the corrosion resistance of the surface.

This study aims to establish a comprehensive model integrating variables from the updated unified theory of acceptance and use of technology (UTAUT), expectation-confirmation model (ECM) and trust to determine what factors influence consumers’ decision to continue using food delivery apps (FDA) after the COVID-19 outbreak in Taiwan.

Data was collected from 350 respondents living in Taiwan via Line using a Google Forms link. A total of 333 valid responses were analyzed after 17 invalid questionnaires were eliminated. To test the suggested study paradigm, partial least squares-structural equation modeling was used as the data analysis approach.

The results indicate FDA users’ continuance intention (CI) is directly significantly affected by performance expectancy, satisfaction and habit. All the constructs of the updated UTAUT theory, confirmation and trust significantly influence the satisfaction of FDA, and users’ satisfaction significantly positively impacts users’ CI.

Although consumers’ intentions toward FDA have previously been the topic of research, there is a paucity of literature that discusses the connections between the variables that influence FDA users’ CI after the COVID-19 pandemic in Taiwan. By focusing on the relationships between the multiple antecedents of FDA users’ CI, this study contributes to reducing the existing literature gap. Explanation surrounding the elements influencing FDA users’ CI is provided by examining several aspects of FDA usage, including technological and psychological postadoption issues.

本研究试图建立一个综合模型, 整合了来自统一接受和使用科技理论（UTAUT）、期望-确认模型（ECM）和信任等变量, 以确定影响消费者在COVID-19疫情爆发后继续使用食品外卖应用(FDA)的因素。

本研究针对台湾的居民通过Line平台使用Google Forms链接收集了350份问卷数据, 经过筛选后得到333份有效回复。为了验证所提出的研究范式, 本研究采用了PLS-SEM作为数据分析方法。

结果表明, FDA用户的继续使用意图受到性能预期、满意度和习惯的直接显著影响。UTAUT理论、期望确认和信任显著影响FDA用户的满意度, 而用户的满意度对用户的继续使用意图产生积极影响。

尽管消费者对FDA的意向不是新的研究的主题, 但在讨论COVID-19疫情后影响FDA用户继续使用意图的变量之间的关系方面, 文献中存在不足。通过探索FDA用户继续使用意图的多个前因关系, 本研究有助于弥补现有文献的空白。通过考察FDA使用的技术和心理因素等多个方面, 本研究提供了解释影响FDA用户继续使用意图的论述。

This research constructs the critical predictors of visitation that shall allow the practitioners to foresee the visitation in the years to come through secondary data. For this study, tourist arrival data associated with the most popular forest park (i.e., Xiton Forest Park) in Taiwan along with relevant socio-economic data are utilized. This research adopts a group of analytical procedures involving correlation analysis, regression, and curve estimation analyses. The results show that the number of holiday per month and the average monthly rainfall have positive and negative correlations, respectively, with the visitation. Meanwhile, average monthly temperature and monthly gross domestic product per capita show a positive correlation in all three analytical methods and therefore are regarded as the primary predictors of tourist arrival. Consequently, this study provides managerial implications to increase the tourist arrivals to the forest park.

The purpose of this study is to describe and observe the influence of boundary slip associated with an arbitrary entrainment angle on the contact lubrication properties of ellipses.

Based on the modified Reynolds equation, the boundary slip of any angle is considered in the elliptic contact, and numerical simulation is carried out. In the above calculation, the progressive mesh densification method is used, which greatly reduces the computation time.

The results indicate that the variation of film thickness corresponding to different entrainment angles is distinct from those without considering boundary slip. In addition, boundary slip reduces the central film thickness and minimum film thickness, which makes the hydrodynamic pressure distribution smoother.

The present study focuses on the specific condition with the arbitrary direction of rolling and sliding velocity found in hypoid gears and worm, and some other components. The influence of boundary slip associated with arbitrary entrainment angle on the lubrication film thickness in elliptical contacts is first revealed, which improves a good understanding of elastohydrodynamic lubrication characteristics.

The purpose of this study is to numerically investigate the time-varying mixed lubrication performance of microgroove journal-thrust coupled bearing (MJTCB) under nonlinear excitation.

A three degree of freedom (3-DOF) dynamic model of the rotor coupling with the transient mixed lubrication behavior is established. Based on numerical predictions, the role of the microgroove on the time-varying mixed lubrication performance of MJTCB is identified. The effects of the microgroove depth, microgroove shape and external load on the time-varying mixed lubrication performance of MJTCB are also studied.

Numerical results show that the effect of the coupling hydrodynamic on the time-varying mixed lubrication performance of the coupled bearing is strengthen with the increasing of microgroove depth. Furthermore, it is found that the optimal microgroove shape for the thrust bearing, arc or rectangle, highly depends on the microgroove depth. Finally, the contact performance of the thrust bearing is slightly affected by the radial external load.

This study is expected to achieve a better understanding of the time-varying mixed lubrication performance of MJTCB under nonlinear excitations.

This study aims to reveal the essential characteristics of nonstationary signals and explore the high-concentration representation in the joint time–frequency (TF) plane.

In this paper, the authors consider the effective TF analysis for nonstationary signals consisting of multiple components.

To make it, the authors propose the combined multi-window Gabor transform (CMGT) under the scheme of multi-window Gabor transform by introducing the combination operator. The authors establish the completeness utilizing the discrete piecewise Zak transform and provide the perfect-reconstruction conditions with respect to combined TF coefficients. The high-concentration is achieved by optimization. The authors establish the optimization function with considerations of TF concentration and computational complexity. Based on Bergman formulation, the iteration process is further analyzed to obtain the optimal solution.

With numerical experiments, it is verified that the proposed CMGT performs better in TF analysis for multi-component nonstationary signals.

In this study, the dynamic characteristics of the water-lubricated rubber bearing considering asperity contact are numerically studied, including water-film stiffness and damping coefficients and plastic-elastic contact stiffness coefficient.

The Kogut-Etsion elastic-plastic contact model is applied to calculate the contact stiffness coefficient at the bearing-bush interface and the perturbed method is used to calculate the stiffness and damping coefficients of water-film. In addition, the rubber deformation is determined by the finite element method (FEM) during the simulation. Parametric studies are conducted to assess the effects of the radial clearance, rubber thickness and elastic modulus on the dynamic characteristic of water-lubricated rubber bearing.

Numerical results indicate that stiffness and damping coefficients of water film and the contact stiffness of asperity are increased with the decreasing of the radial clearance and the dynamic coefficients are less sensitive to the rubber thickness compared with the elastic modulus of rubber. Furthermore, due to the existed groove, a sudden change of the water film direct stiffness and damping coefficients is observed when the eccentricity ratio ranges from 0.6 to 1.0.

It is expected this study can provide more information to establish a dynamic equation of water-lubricated rubber bearings exposed to mixed lubrication conditions.