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This paper aims to propose a deep learning model that can be used to expand the number of samples. In the process of manufacturing and assembling electronic components on the printed circuit board in the surface mount technology production line, it is relatively easy to collect non-defective samples, but it is difficult to collect defective samples within a certain period of time. Therefore, the number of non-defective components is much greater than the number of defective components. In the process of training the defect detection method of electronic components based on deep learning, a large number of defective and non-defective samples need to be input at the same time.

To obtain enough electronic components samples required for training, a method based on the generative adversarial network (GAN) to generate training samples is proposed, and then the generated samples and real samples are used to train the convolutional neural networks (CNN) together to obtain the best detection results.

The experimental results show that the defect recognition method using GAN and CNN can not only expand the sample images of the electronic components required for the training model but also accurately classify the defect types.

To solve the problem of unbalanced sample types in component inspection, a GAN-based method is proposed to generate different types of training component samples and then the generated samples and real samples are used to train the CNN together to obtain the best detection results.

Hydrostatic thrust bearing is a key component of the vertical CNC machining equipment, and often results in friction failure under the working condition of high speed and heavy load. The lubricating oil film becomes thin or breaks because of high speed and heavy load and it affects the high precision and stable operation of the vertical CNC machining equipment; hence, it is an effective way of avoiding friction failure for achieving the oil film shape prediction

For the hydrostatic thrust bearing with double rectangular cavities, researchers solve the deformation of the friction pairs in hydrostatic bearing by using the computation of hydrodynamics, elasticity theory, finite element method and fluid-thermal-mechanical coupled method. The deformation includes heat deformation and elasticity deformation, the shape of gap oil film is got according to the deformation of the friction pairs in hydrostatic bearing, and gets the shape of gap oil film, and determines the influencing factors and laws of the oil film shape, and achieves the prediction of oil film shape, and ascertains the mechanism of friction failure. An experimental verification is carried out.

Results show that the deformation of the rotational workbench is upturned along its radial direction under the working condition of high speed and heavy load. However, the deformation of the base is downturned along its radial direction and the deformation law of the gap oil film along the radius direction is estimated; the outer diameter is close but the inner diameter is divergent wedge.

The conclusion can provide a theoretical basis for the oil film control of hydrostatic thrust bearing and improve the stability of vertical CNC machining equipment.

The purpose of this paper is to study thermal-fluid-solid coupling deformation and friction failure mechanism of bearing friction pairs under the working conditions of high speed and heavy load.

The deformation is simulated based on thermal-fluid-solid coupling method, its deformation distribution law is revealed and the relationships of deformation of friction pairs, rotational speed and bearing weight are obtained.

The results prove that the oil film temperature rises sharply, the lubricating oil viscosity decreases rapidly, the film thickness becomes thinner, the deformation increases, the whole deformation is uneven and the boundary lubrication or dry friction are caused with the increase in rotational speed and bearing load.

The conclusions provide theoretical method for deformation solution and friction failure mechanism of hydrostatic thrust bearing.

This paper aims to describe a theoretical and experimental research concerning influence of recess shape on comprehensive lubrication performance of high speed and heavy load hydrostatic thrust bearing with a constant flow.

The lubrication performance of a hydrostatic thrust bearing with different recess shape under the working conditions of high speed and heavy load has been simulated by using computational fluid dynamics and finite volume method.

It is found that the comprehensive lubrication performance of a hydrostatic thrust bearing with circular recess is optimal. The results demonstrate that recess shape has a great influence on the lubrication performance of the hydrostatic thrust bearing.

The simulation results indicate that to get an improved performance from a hydrostatic thrust bearing with constant flow, a proper selection of the recess shape is essential.

This paper aims to concentrate on recent innovations in flexible wearable sensor technology tailored for monitoring vital signals within the contexts of wearable sensors and systems developed specifically for monitoring health and fitness metrics.

In recent decades, wearable sensors for monitoring vital signals in sports and health have advanced greatly. Vital signals include electrocardiogram, electroencephalogram, electromyography, inertial data, body motions, cardiac rate and bodily fluids like blood and sweating, making them a good choice for sensing devices.

This report reviewed reputable journal articles on wearable sensors for vital signal monitoring, focusing on multimode and integrated multi-dimensional capabilities like structure, accuracy and nature of the devices, which may offer a more versatile and comprehensive solution.

The paper provides essential information on the present obstacles and challenges in this domain and provide a glimpse into the future directions of wearable sensors for the detection of these crucial signals. Importantly, it is evident that the integration of modern fabricating techniques, stretchable electronic devices, the Internet of Things and the application of artificial intelligence algorithms has significantly improved the capacity to efficiently monitor and leverage these signals for human health monitoring, including disease prediction.

Rotational speed and load-carrying capacity are two mutual coupling factors which affect high precision and stable operation of a hydrostatic thrust bearing. The purpose of this paper is to study reasonable matching relationship between the rotational speed and the load-carrying capacity.

A mathematical model of relationship between the rotational speed and the load-carrying capacity of the hydrostatic bearing with double-rectangle recess is set up on the basis of the tribology theory and the lubrication theory, and the load and rotational speed characteristics of an oil film temperature field and a pressure field in the hydrostatic bearing are analyzed, reasonable matching relationship between the rotational speed and the load-carrying capacity is deduced and a verification experiment is conducted.

By increasing the rotational speed, the oil film temperature increases, the average pressure decreases and the load-carrying capacity decreases. By increasing the load-carrying capacity, the oil film temperature and the average pressure increases and the rotational speed decreases; corresponding certain reasonable matching values are available.

The load-carrying capacity can be increased and the rotational speed improved by means of reducing the friction area of the oil recess by using low-viscosity lubricating oil and adding more oil film clearance; but, the stiffness of the hydrostatic bearing decreases.

This paper aims to discuss that a WC/Co-Cr alloy coating was applied to the surface of H13 steel by laser cladding.

The oxidation behavior of the WC/Co-Cr alloy coating at 600°C was investigated by comparing it with the performance of the steel substrate to better understand the thermal stability of H13 steel.

The results showed that the WC/Co-Cr alloy coating exhibited better high-temperature oxidation resistance and thermal stability than did uncoated H13 steel. The coated H13 steel had a lower mass gain rate and higher microhardness than did the substrate after different oxidation times.

The WC/Co-Cr alloy coating was composed of e-Co, CW3, Co6W6C, Cr23C6 and Cr7C3; this mixture offered good thermal stability and better high-temperature oxidation resistance.

The purpose of this paper is to solve the tracking problem for free-floating space manipulators (FFSMs) in task space with parameter uncertainties and external disturbance.

In this paper, the novel cerebellar model articulation controller (CMAC) is designed with the feedback controller. More precisely, the parameter uncertainties in the FFSM are considered for achieving the robustness.

By using the dynamically equivalent model, the CMAC can be designed and trained with the desired performance, such that the prescribed trajectory can be followed accordingly. The simulation results are presented for illustrating the validity of the derived results.

Based on the designed CMAC, the tracking error would be approaching zero by choosing appropriate quantization level in CMAC and the corresponding learning rules can be tuned online.

This paper examines the in-depth relationship between religious beliefs and individual social class mobility expectations in China.

The data used in this article are mainly from the China Comprehensive Social Survey in 2010 (CGSS2010). Compared with other years' CGSS data, CGSS2010 includes a module on religious topics, and the questionnaire information related to religion is more comprehensive and suitable for in-depth analysis.

The results show that religious beliefs have a significant positive impact on personal social class mobility expectations. Based on the principle of diminishing marginal returns on capital, the positive impact of religious belief on the expectation of individual social class mobility is more significant in groups with nonagricultural household registration, higher education level, older age and better family background conditions. However, with the further improvement of family background conditions, this positive impact begins to weaken. In addition, possible channels of action include prejudice effects, psychological effects, individual capital effects and social capital effects. The results of other effects are positive except for the prejudice effect. Overall, religious beliefs, as one of the important components of contemporary Chinese culture, have a positive significance for the “Chinese Dream”.

There is also little literature globally that provides an in-depth analysis of the relationship between religion and economic development. Studies have led to an understanding of the relationship between religious beliefs and individual social class mobility expectations. But it is unclear whether theories developed based on Western spiritual experience will be applicable to China or not. The authors have tested for China.

This study aims to focus on understanding how the characteristics of the bed and breakfast (B&B) host responses to online reviews impact the subsequent business performance of review volume, including volume, timeliness and length of responses.

The study constructs a theoretical framework to model for the relationships among characteristics of the B&B host responses, heterogeneity of B&B houses and subsequent reviews. The model is then examined by an econometric model using data from Ctrip.com.

Prompt and lengthy responses to online reviews increase the number of subsequent reviews, and the effects are larger for higher level houses. The main theoretical contribution is to build a model explaining how multiple attributes of the host responses can affect business performance and how these effects are moderated by the class levels of B&B houses, which are empirically tested by real data.

This study highlights managerial implications of host responses for online B&B business practices. For the higher-quality B&B houses, based on price and reviews, lengthy and timely responses are necessary, as tourists expect increased customer service from these hosts.

The research provides insights in understanding the mechanism of B&B host responses on subsequent reviews. To the best of the authors’ knowledge, this is the first study to demonstrate the moderating effect of price and volume of online reviews on responses.

共享民宿房主对在线评论的反应如何影响后续评论：房屋等级的调节效应

本研究旨着重探讨民宿房主对网上评论的回应特性如何影响评论量的后续经营绩效, 包括回复数量、及时性和回复的长度。

方法 -- 本研究首先构建理论框架, 对民宿房主的在线回应特征、民宿房屋的异质性特征与后续评论之间的关系进行建模。该模型通过一个计量经济学模型对从携程网收集的数据进行了检验.

研究结果 -- 本研究的结果显示, 对在线旅游评论提供及时和冗长的回复, 可能会增加未来的预订数量, 从而增加后续的评论,并且这个影响随着房屋等级的提高而增加。本文的主要理论贡献是建立一个模型来解释房屋主人在线回应的多重属性如何影响他们的经营绩效, 以及这些影响是如何被房屋等级所调节的,并通过真实数据对理论进行了验证。

研究意义 -- 该研究有助于将研究重点从在线评论和口碑转移到管理层的回应效应。我们的研究结果印证了之前的研究关于评论量可以影响口碑信息说服力及其他口碑相关特征（如管理层回应）影响的结论。

管理启示 -- 本研究的结果, 向民宿房主提供了具体的管理启示, 为网上民宿商业管理提供参考。对于价格更高、在线声誉较高的B&B房屋, 应提供更多及时的回应, 因为游客期望得到更友好的客户服务。

原创性 -- 这项研究提供了关于民宿房主在线回应对后续评论量影响机制的探索。并将是首次尝试验证价格和在线评论量对在线回复影响的调节作用。

Entendiendo cómo las respuestas de los dueños de establecimientos de B&B a las opiniones de los turistas en línea promoverán las opiniones subsiguientes: Los efectos moderadores del nivel de clase de los establecimientos de B&B

Resumen

Propósito -- Este estudio se centra en comprender cómo las características de las respuestas de los anfitriones de alojamientos B&B influyen en el rendimiento empresarial de volumen de reseñas; esto incluye el número de respuestas, la puntualidad de la respuesta y la duración de la misma.

Metodología -- En primer lugar, el estudio construye un marco teórico para establecer un modelo de relación entre las características de las respuestas de los anfitriones de alojamientos, heterogéneos de alojamientos B&B y las revisiones posteriores. A continuación, el modelo es examinado por un modelo econométrico a partir de los datos recogidos en ctrip.com.

Resultados -- Se ha demostrado que las respuestas rápidas y extensas a las reseñas en línea pueden aumentar potencialmente el número de reseñas posteriores, y tuvieron un mayor impacto en las viviendas de gran altura. La principal contribución teórica de este trabajo es construir un modelo para explicar cómo los múltiples factores de la respuesta de los anfitriones pueden afectar a su rendimiento empresarial y cómo estos efectos son moderados por las nivel de los alojamientos B&B, través de los datos reales de la prueba empírica.

Implicaciones prácticas -- Proporciona una referencia para la práctica empresarial de los alojamientos B&B en línea, al informar sobre las implicaciones específicas de gestión para los anfitriones de alojamientos B&B. En el caso de las casas de alojamientos B&B de mayor nivel, con precios más altos y más reseñas en línea, se deberían dar más respuestas oportunas, ya que los turistas esperan de los anfitriones un servicio de atención al cliente más amable.

Originalidad -- La investigación permite comprender el mecanismo de las respuestas de los anfitriones de alojamientos B&B en las reseñas posteriores. Sería el primer intento de demostrar el efecto moderador del precio y el volumen de las reseñas en línea sobre el impacto de las respuestas.