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To meet the high stiffness requirement of bearings used in high-precision spindles, this paper aims to propose a novel kind of bearing composited by hydrostatic cavities and tilting pads with preload.

Cavities are cut on the oil seal surface of a hybrid bearing, in which the tilting pads are set up. The load of the bearing is carried by the hydrostatic cavities and tilting pads. The structural features of this compound bearing and the controlling variables of the main stiffness coefficient are presented. Two basic design principles are proposed on the basis of equal machining clearance (EMC) and equal installation clearance (EIC).

The theoretical analysis indicates that the stiffness of compound bearings under the EMC condition increases to infinity monotonously when the preload coefficient of the tilting pad tends to 1, while the stiffness under the EIC condition has a peak value. Therefore, a synthetic design principle is proposed by synthetically using the above-mentioned two principles. The applicable range of the three principles is discussed through an example.

The study about technological combination of hydrostatic cavity and tilting pad in this paper can provide suggestions for the design of a high-stiffness bearing in a precision spindle.

Urban parks play a key role in recreational activities, public health, and ecosystem services in urban areas. Using GIS and Fragstats, this study investigated the spatiotemporal dynamics of urban parks in Xi'an, China from 1949 to 2015 and the corresponding driving forces. The results show that the number and area of parks in Xi'an increased constantly during this period, especially from 2000 to 2015. Up to 2015, small green spaces, usually adjacent to streets, occupied the largest proportion among all types of parks. Archaeological parks were the largest in total area, but wetland parks were leading in average size of a single park. The density of parks was negatively correlated with their distance to the Clock Tower at the center of Xi'an. The dynamics of urban parks in highly urbanized areas were significantly different from that of their counterparts in suburban areas. Driving forces such as urban planning, urbanization and green space policies, and milestone events in the city's development jointly had a great effect on the distribution of parks in Xi'an. The research outcomes will support the upcoming Green Space Planning of Xi'an and benefit the pursuit of sustainability and human wellbeing.

The purpose of this paper is to discuss the opportunity of utilizing Tang dynasty history, heritage, buildings and names in the effort to place brand the contemporary city Xi'an.

The paper presents a conceptual framework for place branding cities consisting of two main dimensions. The first describes the continuum of functional versus emotional values within a city; the second measures the degree to which the image of a place is historical or contemporary. The paper then employs historical analysis to examine the meaning and construction of a Tang dynasty brand for place branding twenty‐first century Xi'an.

While Xi'an may possess an illustrious historical identity, the contemporary city is still searching for an image. Xi'an's glorious heritage attracts considerable tourism, but has not yet drawn substantial business, foreign direct investment or talents to contribute to and support economic development of the metropolitan region.

Historical analysis of a city can allow a reconstruction of identity in the modern context. Since this is a case study of one key Chinese city, additional cases are needed for other historically important cities to see their influence on business and marketing development.

Cities that are attempting to grow should consider their historical legacy. Building on images of the past, they can leapfrog development and establish a brand identity. Modernization was often thought of as a practical developmental tool. Building on the history of a region, modernization can take unique characteristics and differentiated developmental patterns.

Few, if any, studies examined the historical antecedents of a remaking and a re‐branding of a city. Destination marketing is an emerging area of research. Xi'an was a great, pivotal city in the past. This paper explores how one region built on the greatness of the past can re‐emerge in modern society.

The purpose of this paper is to study the importance of image data in hotel selection-recommendation using different types of cognitive features and to explore whether there are reinforcing effects among these cognitive features.

This study represents user-generated images “cognitive” in a knowledge graph through multidimensional (shallow, middle and deep) analysis. This approach highlights the clustering of hotel destination imagery.

This study develops a novel hotel selection-recommendation model based on image sentiment and attribute representation within the construction of a knowledge graph. Furthermore, the experimental results show an enhanced effect between different types of cognitive features and hotel selection-recommendation.

This study enhances hotel recommendation accuracy and user satisfaction by incorporating cognitive and emotional image attributes into knowledge graphs using advanced machine learning and computer vision techniques.

This study advances the understanding of user-generated images’ impact on hotel selection, helping users make better decisions and enabling marketers to understand users’ preferences and trends.

This research is one of the first to propose a new method for exploring the cognitive dimensions of hotel image data. Furthermore, multi-dimensional cognitive features can effectively enhance the selection-recommendation process, and the authors have proposed a novel hotel selection-recommendation model.

This paper aims to propose a novel multiple transient modeling scheme for the 12-pulse phase-shifting reactor (PSR) rectifier to enhance the efficiency of full-cycle design evaluation.

The detailed time-domain method is adopted to model the rectifier at the behavioral layer. The diode bridges/transformer model at the architecture layer is established by using the switch function and Park transformation. The frequency domain model at the functional layer is derived with the time-varying Fourier decomposition and frequency-shifting. At the component layer, the magneto-thermal characteristics of the rectifier are analyzed with field-circuit and magnetic-thermal coupling methods. A computer-aided design program integrating multiple modeling is also developed for industrial product design.

The function layer modeling is preferred in the initial design stage, making up for the lack of modeling accuracy at the architectural layer and the lack of modeling rapidity at the behavioral layer. The component modeling is irreplaceable for the detailed evaluation in the latter design stage. The multiple modeling scheme based on the four-layer modeling helps the designers achieve high-quality products with a short development cycle.

The singular transient modeling cannot cover the needs of different stages in the full-cycle design evaluation. This paper fills this gap with a novel multiple modeling scheme. Meanwhile, the proposed multiple modeling scheme and developed computer-aided design program provide a great convenience for full cycle design evaluation of the 12-pulse PSR rectifier.

This paper aims to develop an additive manufacturing technique for complex zirconia ceramic dental bridges.

To carry out this study, a dental bridge model was obtained by three-dimensional reverse engineering, and a light-curable zirconia ceramic suspension was formulated. Zirconia bridges were manufactured by stereolithography and then treated by vacuum freeze drying, vacuum infiltration and sintering. The optimal scanning speed was determined according to the shape precision comparison. Then, characteristics of the sintered ceramic parts were tested as size shrinkage, relative density, surface Vickers hardness, surface roughness and microstructure.

The method for preparation of light-curable zirconia suspension (40 volume per cent solid loading) with a viscosity value of 127 mPa·s was proposed. The optimal laser scanning speed for zirconia bridge fabrication was 1200 mm/s. A relative density of 98.58 per cent was achieved; the obtained surface Vickers hardness and surface roughness were 1,398 HV and 2.06 µm, respectively.

This paper provides a potential technical method for manufacturing complex zirconia dental bridges and other small complex-shaped ceramic components which are difficult to be made by other manufacturing techniques.

This study aims to promote the anti-disturbance and tracking accuracy performance of the servo systems, in which a modified active disturbance rejection control (MADRC) scheme is proposed.

An adaptive radial basis function (ARBF) neural network is utilized to estimate and compensate dominant friction torque disturbance, and a parallel high-gain extended state observer (PHESO) is employed to further compensate residual and other uncertain disturbances. This parallel compensation structure reduces the burden of single ESO and improves the response speed of permanent magnet synchronous motor (PMSM) to hybrid disturbances. Moreover, the sliding mode control (SMC) rate is introduced to design an adaptive update law of ARBF.

Simulation and experimental results show that as compared to conventional ADRC and SMC algorithms, the position tracking error is only 2.3% and the average estimation error of the total disturbances is only 1.4% in the proposed MADRC algorithm.

The disturbance parallel estimation structure proposed in MADRC algorithm is proved to significantly improve the performance of anti-disturbance and tracking accuracy.

The study aims to devise a comprehensive evaluation model (CEM) for evaluating spatial equity in the layout of elderly service facilities (ESFs) to address the inequity in the layout of ESFs within city center communities characterized by limited land resources and a dense elderly population.

The CEM incorporates a suite of analytical tools, including accessibility assessment, Lorenz curve and Gini coefficient evaluations and spatial autocorrelation analysis. Utilizing this model, the study scrutinized the distributional equity of three distinct categories of ESFs in the city center of Xi’an and proposed targeted optimization strategies.

The findings reveal that (1) there are disparities in ESFs’ accessibility among different categories and communities, manifesting a distinct center (high) and periphery (low) distribution pattern; (2) there exists inequality in ESFs distribution, with nearly 50% of older adults accessing only 18% of elderly services, and these inequalities are more pronounced in urban areas with lower accessibility, and (3) approximately 14.7% of communities experience a supply-demand disequilibrium, with demand surpassing supply as a predominant issue in the ongoing development of ESFs.

The CEM formulated in this study offers policymakers, urban planners and service providers a scientific foundation and guidance for decision-making or policy amendment by promptly assessing and pinpointing areas of spatial inequity in ESFs and identifying deficiencies in their development.

Previous studies on housing affordability in China were concentrated in China’s coastal and central regions. The purpose of this paper is to investigate housing affordability of urban residents in Northwest China. Moreover, this paper attempts to understand the consistency and influencing factors of various indicators on the evaluation of housing affordability.

This paper uses multiyear data on house sales, residents’ incomes and living expenses from 2011 to 2022. House price-to-income ratio, housing affordability index and residual income approach were calculated by using these data and used as the measure of housing affordability.

The results show that there are obvious differences in the housing affordability among the Xi’an, Lanzhou and Yinchuan during 2011–2022, and the housing affordability of residents in cities with small population and economic scale is better. The ability of most urban residents to afford suitable housing is still poor, and the ability to afford small-sized housing is better. Most families with below-middle income have poor housing affordability. It is also observed that although various indicators had similarities in the evaluation of residents’ housing affordability, the comprehensive evaluation results of multiple indicators were more reliable.

The research results provide a basis for the decision-making of the government’s urban housing policy and improvement of residents’ housing conditions.

The results have a clear understanding of the housing affordability of urban residents in Northwest China. The study found that the geographical location and topography of the city is also a factor affecting the housing affordability.

Although manufacturer-initiated rewards are widely used to secure distributors’ compliance, the spillover effect on unrewarded distributors (i.e. observers) in the same distribution channel is under-researched. Using insights from social learning theory, this paper aims to investigate how manufacturer-initiated rewards affect observers’ expectation of reward and shape observers’ compliance toward the manufacturer. Furthermore, this paper explores how such effects are contingent upon distributor relationship features.

To test the hypotheses, hierarchical multiple regression and bootstrapping analyses were performed using survey data from 280 Chinese distributors.

The magnitude of a manufacturer-initiated reward to a distributor stimulates expectation of reward among observers, which enhances compliance; observers’ expectation of reward mediates the impact of reward magnitude on compliance. Moreover, network centrality (of the rewarded peer) negatively moderates the positive impact of reward magnitude on observers’ expectation of reward, whereas observers’ dependence (on the manufacturer) positively moderates this dynamic.

Manufacturers should pay attention to the spillover effects of rewards. Overall, they should use rewards of appropriate magnitude to show willingness to recognize outstanding distributors. This will inspire unrewarded distributors, which will then be more compliant. Furthermore, manufacturers should know that specific types of distributor relationship features may significantly vary the spillover effects.

This study illuminates the spillover effects of manufacturer-initiated reward by opening the “black box” of the link between reward magnitude and observers’ compliance and by specifying the effects’ boundary conditions.