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Structural design theory and method for the polyurea coating system have rarely been developed. The normally used experience-based design method may lead to unsafe, unreasonable and uneconomic results. The purpose of this paper is to investigate the deformation and failure behaviour of the polyurea coating so as to propose a rational design method.

In this study, the fundamental theories concerning the nonlinear analysis of polyurea coating were discussed. Nonlinear Finite Element Method (FEM) models were built to investigate the mechanical behaviour, peeling behaviour and failure mode of the polyurea coating under various conditions, such as surface fracturing, surface hydraulic pressure and reverse hydraulic peeling.

The main conclusions are as follows. The peeled coating at the crack location exhibits a tensile-bending stress state. Coating material damage may occur at the stress concentration point. The maximum stress increases with the increase in the hydraulic pressure and cohesive strength. The peeling length of the coating decreases with the increase in cohesive strength and increases with the increase in fracture width. The reverse hydraulic pressure-induced blister edge stress concentration is the main trigger of the polyurea coating blistering damage. The blistering height decreases with increasing coating thickness and increases with increasing blistering radius and hydraulic load. The maximum stress increases with increasing blistering radius and hydraulic load. Finally, the frame of design and simple design programme were proposed.

Currently, a design method for polyurea anti-seepage coating can hardly be found. The reason is that the anti-seepage coating has only been recognized as a water-proofing layer, the mechanical behaviour of which has been ignored. This study focused on the mechanical behaviour of the anti-seepage coating and investigated the deformation and failure behaviour of the coating structure under various loading conditions through nonlinear FEM analysis. These research results offer a better understanding concerning the mechanical behaviour and design method of the polyurea anti-seepage coating.

Multilayer composite liner structures are the primary structural form of hydraulic tunnels. However, the bearing mechanism of multilayer composite liners has not been investigated thoroughly. Many existing design schemes do not properly achieve a balance between structural safety, anti-seepage capacity, and cost effectiveness. Thus, a new composite liner structure type and its theoretical model was proposed.

A novel hydraulic tunnel composite liner structure with a polyurea spray coating interlayer was proposed in this study. A theoretical model based on the state-space method was developed and verified using FEM models and existing theoretical models. Parametric analysis was conducted based on the theoretical model to investigate the influence of various variables, including interfacial shear stiffness, inner liner thickness, and outer liner elastic modulus.

It was concluded that the proposed theoretical model can be used successfully to calculate multilayer composite liner structures with high calculation efficiency. The overall deformation stiffness of the composite liner system increased with the interfacial shear stiffness. The sprayed coating interlayer significantly affects the residual force distribution between the outer and inner liners, which can also be affected by the adjustment of the thickness of the outer and inner liners. Thus, attention should be paid to these factors in the rational design of the proposed composite liner system.

With the development of China’s water conservancy projects, complex geological conditions, high surrounding rock stress, high internal and external water pressures, and other unique application scenarios have gradually increased. This places higher requirements on the bearing performance and impermeability of hydraulic tunnel lining structures. On the other hand, conventional hydraulic tunnel lining structures can hardly achieve a satisfactory balance between economy, structural safety, and impermeability. Thus, the proposed structure has the potential to be used in a wide range of applications.

The behavior of joints has a significant effect on the stability of water conveyance tunnel. The purpose of this paper is to study the contact and friction at the joint of the tunneling segment lining and establish its contact friction model. At the same time, the stress and deformation characteristics at the joint of the segment under hydrostatic load are analyzed.

In this study, the contact and friction in a bolted joint are examined using shear testing. The feasibility of the proposed model is verified by a numerical simulation of tests and a theoretical analysis. Accordingly, the effect of joints on the lining is explored under internal hydrostatic loading.

The results show that the openings of tunnel segments in joints gradually expand from the positions of the inner and outer edges to the location of the bolt. Moreover, the stress concentration zone is formed at the bolt. Under hydraulic loading, the opening displacement at the joint increases as the water pressure increases; nevertheless, it does not exceed engineering requirements. When the water pressure of the tunnel lining joint reaches 0.5 MPa, the opening of the joint slowly increases. When the water pressure exceeds 0.7 MPa, the opening of the joint rapidly and significantly increases.

Contact and friction in a bolted joint were examined using shear testing. A cohesive zone model of bolted joints was proposed based on test results. The influence of joint behavior on the stability of water conveyance tunnel was studied.

Combining with an instance of rectification and reinforcement of a brick-concrete structure house in the Yunnan province, a comprehensive landing method was proposed. The building was reinforced, for the existing problems, on the basis of the analysis of the building tilt reasons. In order to ensure building safety in the process of rectifying inclination, the anchor static pile was used. The result showed that the inclination rate of the building returned to 3 % from 14.4 %, which proves the effectiveness of the proposed method.

Additive manufacturing (AM), a method used in the nuclear, space and racing industries, allows the creation of customized titanium alloy scaffolds with highly defined external shape and internal structure using rapid prototyping as supporting external structures within which bone tissue can grow. AM allows porous tantalum parts with mechanical properties close to that of bone tissue to be obtained.

In this paper, porous tantalum structures with different scan distance were fabricated by AM using laser multi-layer micro-cladding.

Porous tantalum samples were tested for resistance to compressive force and used scanning electron microscope to reveal the morphology of before and after compressive tests. Their structure and mechanical properties of these porous Ta structures with porosity in the range of 35.48 to 50 per cent were investigated. The porous tantalum structures have comparable compressive strength 56 ∼ 480 MPa, and elastic modulus 2.8 ∼ 9.0GPa, which is very close to those of human spongy bone and compact bone.

This paper does not demonstrate the implant results.

It can be used as implant material for the repair bone.

It can be used for fabrication of other porous materials.

This paper system researched the scan distance on how to influence the mechanical properties of fabricated porous tantalum structures.

The purpose of this paper is to develop a flexible design-oriented development cost method for commercial aviation aircraft based on small sample and poor information.

To predict the development cost of commercial aviation aircraft accurately, the methodology is based on the collected cost data and actual technical, and then the cost prediction relationships derived from an exhaustive statistical and filtered from regression analysis are incorporated. A series of regression equations with high regression coefficient are yielded after the cost driving factors of the development cost are fixed. Next, several sets of equations with high regression coefficient are selected for final integration. It is a flexible method that can be used efficiently to predict the cost of commercial aviation aircraft.

The development of commercial aviation aircraft has relatively a late start and no cost prediction model has been suitable for small sample, the proposed method is expected and is rather desirable.

By comparing the approach with the ordinary regression model and back propagation (BP) neural network, the scheme in this work is more efficient and convenient.

The results obtained in this paper show that the proposed method not only has a certain degree of versatility, but also can provide a preliminary prediction of the development cost of commercial aviation aircraft.

The purpose of this paper is to research the price strategies of online knowledge payment product by considering network externality in the C2C sharing economy.

Considering the characteristics of online knowledge goods and the social network externality of consumers, this study establishes a consumer utility function. On this basis, a multistage game pricing model of online knowledge products is established based on three kinds of network price strategies under a completely competitive market structure. It also analyzes the influence of consumer social network structure and consumer utility on online knowledge product pricing and producer profit, as well as the influence of consumer quantity and discount rate on pricing strategy.

The consumer social network and consumer utility affect the pricing of online knowledge product under different price strategies. In the growth period of the platform, adopting the price discrimination strategy, the profit of producers is significantly higher than that of other price strategies, and producers should choose effective price strategies for reasonable pricing in combination with their own sales objectives.

This study enriches the literature on the pricing model of online knowledge payment product and owns a practical significance to guide the knowledge producers’ marketing strategies to increase profit.

The purpose of this study is to systematically analyze the evolution of health tourism development, identify relevant themes and segments of health tourism research and offer future research directions and practical implications for academic researchers and tourism practitioners worldwide using China as an example.

Using a bibliometric analysis, the present study comprehensively analyzes the theme, segments and the evolution of health tourism research over the past 40 years in China.

Major findings show that health tourism research in China could be divided into four stages with different characteristics, and three segments, including wellness tourism, health and wellness tourism and medical tourism. Findings also reveal the trend of health tourism development tends to be industrialized, diversified and systematic under the guidance of recent policies. Theoretically, based on the theoretical framework developed by Hall (2011), the present study contributes to the establishment and extension of the framework for health tourism within the context of China. Practically, findings can provide health tourism-related policy implications for the future development of health or health sector-integrated tourism.

The study proposes possible collaboration between government and academia in terms of health tourism-related policy formulation.

Through 40-year bibliometric analysis of health tourism evolution in China, the present study explores the main themes of health tourism development, identifies the segments of health tourism and analyzes the development stages of health tourism. Findings should be of use to international readers to better understand the uniqueness of health tourism development and find out possible future health tourism development research directions. As a result, major contributions of this paper are the comprehensive analysis of the evolution of health tourism research and the implications on other countries and regions to adopt a pragmatic approach to explore the trend and unique characteristics of health tourism for future development.

本研究旨在系统地分析中国健康旅游的演变过程, 探索健康旅游研究的相关主题及细分领域, 并为全球学术研究人员及旅游从业者提供未来的研究方向。

此研究通过文献计量学的研究方法, 全面分析了中国近40年健康旅游研究的主题、细分以及演变。

中国健康旅游研究根据其发展特点可以分为四个阶段及三个细分主题：分别是养生旅游, 康养旅游及医疗旅游。调查结果还表明, 在近期政策的引导下, 健康旅游发展趋于产业化、多元化和系统化。从理论意义来说, 本研究基于Hall (2011) 提出的理论框架, 构建了中国背景下的健康旅游框架。从实践意义来说, 研究结果可以为健康和旅游业相关部门提供政策建议。

此研究还有助于促进政府和学术界在健康旅游政策制定方面的合作。

此研究通过对中国近40年健康旅游的研究进行文献计量分析, 探索了健康旅游发展的主题, 分析了健康旅游的细分市场以及发展阶段。研究结果有助于学术界及旅游业更好地了解健康旅游发展的独特性及未来健康旅游的研究方向。因此, 本研究的主要贡献是全面地分析了健康旅游研究的演变, 并有助于其他国家/地区探索未来健康旅游的发展趋势和其独特特征。

El propósito del presente estudio es analizar sistemáticamente la evolución del desarrollo del turismo de salud, identificar temas y segmentos relevantes de la investigación en turismo de salud y ofrecer direcciones de investigación futuras e implicaciones prácticas para investigadores académicos y profesionales del turismo en todo el mundo utilizando a China como ejemplo.

Mediante un análisis bibliométrico, el presente estudio analiza exhaustivamente la temática, los segmentos y la evolución de la investigación sobre turismo de salud en los últimos 40 años.

Los principales hallazgos muestran que la investigación del turismo de salud en China podría dividirse en cuatro etapas con diferentes características y tres segmentos, incluido el turismo de bienestar, el turismo de salud y bienestar y el turismo médico. Los hallazgos también revelan que la tendencia del desarrollo del turismo de salud tiende a ser industrializado, diversificado y sistemático bajo la guía de políticas recientes. El presente estudio hace aportes tanto teóricos como prácticos. Teóricamente, basado en el marco teórico desarrollado por Hall (2011), el presente estudio contribuye al establecimiento y extensión del marco para el turismo de salud en el contexto de China. En la práctica, los hallazgos pueden proporcionar implicaciones políticas relacionadas con el turismo de salud para el desarrollo futuro de la salud o el turismo integrado en el sector de la salud.

El estudio también propone una posible colaboración entre el gobierno y la academia en términos de formulación de políticas relacionadas con el turismo de salud.

A través del análisis bibliométrico de 40 años de la evolución del turismo de salud, el presente estudio explora los temas principales del desarrollo del turismo de salud, identifica los segmentos del turismo de salud y analiza las etapas de desarrollo del turismo de salud. Los hallazgos deberían ser de utilidad para los lectores internacionales para comprender mejor la singularidad del desarrollo del turismo de salud y descubrir posibles direcciones futuras de investigación sobre el desarrollo del turismo de salud. Como resultado, las principales contribuciones de este documento son el análisis exhaustivo de la evolución de la investigación en turismo de salud y las implicaciones en otros países y regiones para adoptar un enfoque pragmático para explorar la tendencia y las características únicas del turismo de salud para el desarrollo futuro.

In terms of understanding the new issues emerging in the practice of monetary policies and how to evaluate the latest theories of monetary policy, this paper proposes referring to Das Kapital and developing a monetary policy theory grounded in Marxist political economy.

Based on the discussion of interest-bearing capital in Das Kapital and using a heterogeneous agent model, this paper tries to explain the determining mechanism of interest rate, leverage ratio, and asset price.

The research finds that if there are differences in the techniques possessed by capital, the resulting disparities in production efficiency will lead to differences in profit rates and further influence the functional choices of capital in the movement of social total capital. Thus, with the formation of lending relationships, interest rates, leverage ratios, and asset prices will be endogenously determined simultaneously. Moreover, as the degree of technological diffusion influences the industrial capitalists’ willingness to take loans as well as the level of profit rates, there may be counter-cyclical changes in the returns on productive investment and financial investment at different stages of the technology life cycle, contributing to diverting funds out of the real economy. Besides, this paper discusses the challenges, tools, and goals of monetary policy within the credit money system.

Clarify the intrinsic mechanism of the functional differentiation of capital determined by heterogeneous technologies and exogenous capital-labor relation and analyze the impact of capital differentiation on the economy.

This paper aims to help hosts or service providers of sharing economy-based accommodation (SEA) to attract new customers and retain existing customers by exploring the antecedents and outcomes of customers’ participation intention.

A questionnaire-based empirical study was conducted to explore the proposed relationships in SEA. Partial least squares modeling with SmartPLS was used to estimate the model and interpret the results.

The study shows that personal factors (utilitarian and hedonic motivation) positively influence customers’ participation intention. The relationship between environmental stimuli (perceived information fit-to-task and perceived visual appeal) and participation intention is negatively moderated by hedonic motivation. Furthermore, the results suggest a positive effect of participation intention on customer engagement behavior and the partial mediating role of experience evaluation.

This paper provides industry practitioners of SEA with valuable insights on attracting new customers and retaining regular customers. First, they can distinguish customers in terms of motivation and provide information based on their requirements. Second, they can encourage customers to evaluate their experience and provide feedback, which would help in promoting the accommodation and service and building a long-term and harmonious relationship with the customers.

This study first investigates the interaction effect of personal motivation and environmental stimuli on participation intention in SEA. It further examines the influence of participation intention on customer engagement behavior and the mediating role of experience evaluation.

本论文旨在帮助SEA(共享经济住宿)的民宿老板或服务提供者, 通过探索顾客参与和契合的影响因子和反应变量, 来吸引新顾客以及保留老顾客。

本论文采用问卷形式实际调研, 探索SEA中的各种假设关系。本论文采用SmartPLS软件, 使用PLS分析法来检验模型以及展示分析结果。

本论文结果表明, 个人因素（功利与享乐需求）正向影响顾客参与。环境因素（感知信息适合和感知视觉吸引）与参与意愿之间被享乐需求负向调节。此外, 结果还表明参与意愿对于顾客契合行为有着正向作用, 以及体验评价的部分中介效应。

本论文为SEA企业从业人员提供如何吸引新顾客以及留住老顾客的宝贵见解。首先, 顾客根据需求和基于他们的需求所提供的信息可进行区分。第二, 企业主应该鼓励顾客评价他们的体验和提供反馈, 从而帮助提高住宿服务以及建立与顾客长期和谐的关系。

本论文首先调研了个人需求和环境刺激对SEA参与意愿的相互作用。其次, 本论文还检验了参与意愿对于顾客契合行为的作用, 以及体验评价的中介效应。