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The purpose of this paper is to initiate investigations to develop near infrared (NIR) spectroscopy coupled with spectral dimensionality reduction and multivariate calibration methods to rapidly measure cotton content in blend fabrics.

In total, 124 and 41 samples were used to calibrate models and assess the performance of the models, respectively. The raw spectra are transformed into wavelet coefficients. Multivariate calibration methods of partial least square (PLS), extreme learning machine (ELM) and least square support vector machine (LS-SVM) were employed to develop the models using 100 wavelet coefficients. Through comparing the performance of PLS, ELM and LS-SVM models with new samples, the optimal model of cotton content was obtained with the LS-SVM model.

The correlation coefficient of prediction (r_p) and root mean square errors of prediction were 0.99 and 4.37 percent, respectively. The results suggest that NIR spectroscopy, combining with the LS-SVM method, has significant potential to quantitatively analyze cotton content in blend fabrics.

It may have commercial and regulatory potential to avoid time-consuming work, costly and laborious chemical analysis for cotton content in blend fabrics.

The literature review aims to facilitate a broader understanding of on-demand service platform operations management and proposes potential research directions for scholars.

This study searches four databases for relevant literature on on-demand service platform operations management and selects 72 papers for this review. According to the research context, the literature can be divided into research on “a single platform” and research on “multiple platforms”. According to the research methods, the literature can be classified into “Mathematical Models”, “Empirical Studies”, “Multiple Methods” and “Literature Review”. Through comparative analysis, we identify research gaps and propose five future research agendas.

This paper proposes five research agendas for future research on on-demand service platform operations management. First, research can be done to combine classic research problems in the field of operations management with platform characteristics. Second, both the dynamic and steady-state issues of on-demand service platforms can be further explored. Third, research employing mathematical models and empirical analysis simultaneously can be more fruitful. Fourth, more research efforts on the various interactions among two or more platforms can be pursued. Last but not least, it is worthwhile to examine new models and paths that have emerged during the latest development of the platform economy.

Through categorizing the literature into two research contexts as well as classifying it according to four research methods, this article clearly shows the research progresses made so far in on-demand service platform operations management and provides future research directions.

High temperature gradient induces high residual stress, producing an important effect on the part manufacturing during laser powder bed fusion (LPBF). The purpose of this study is to investigate the effect of the molten pool mode on the thermal stress of Ti-6Al-4V alloy during different deposition processes.

A coupled thermal-mechanical finite element model was built. The developed model was validated by comparing the numerical results with the experimental data in the maximum molten pool temperature, the molten pool dimension and the residual stress described in the previous work.

For the single-track process, the keyhole mode caused an increase in both the maximum stress and the high-stress area compared with the conduction mode. For the multitrack process, a lower tensile stress around the scanning track and a higher compressive stress below the scanning track were found in the keyhole mode. For the multilayer process, the stress along the scanning direction at the middle of the part changed from tensile stress to compressive stress with the increase in the deposition layer number. As the powder layer number increased, the stress along the scanning direction near the top surface of the part decreased while the stress along the deposition direction obviously increased, indicating that the stress along the deposition direction became the dominant stress. The keyhole mode can reduce the residual stress near the top of the part, and the conduction mode was more likely to produce a low residual stress near the bottom of the part.

The results provide a systematic understanding of thermal stress during the LPBF process.

Although an important facet of modernist architecture in which function plays a prominent role, building flexibility is not entirely a new concept. Its relevance transcends generations, allowing space and structure to evolve through time. This paper investigates the relationship among main building structures, infill elements, and space by studying examples in ancient Chinese architecture. It reveals the role of building owners, users, and craftsmen from a survey of historical documentation. In studying these examples, it is concluded that craftsmen in ancient China were involved not only during the construction phase but throughout the period of use as well. Thus, in select cases, the relationship between craftsmen and owners or users had been preserved for generations. Finally, this paper suggests potential strategies for the building industry and technology in the move towards sustainable development.

High residual stress caused by the high temperature gradient brings undesired effects such as shrinkage and cracking in selective laser melting (SLM). The purpose of this study is to predict the residual stress distribution and the effect of process parameters on the residual stress of selective laser melted (SLMed) Inconel 718 thin-walled part.

A three-dimensional (3D) indirect sequentially coupled thermal–mechanical finite element model was developed to predict the residual stress distribution of SLMed Inconel 718 thin-walled part. The material properties dependent on temperature were taken into account in both thermal and mechanical analyses, and the thermal elastic–plastic behavior of the material was also considered.

The residual stress changes from compressive stress to tensile stress along the deposition direction, and the residual stress increases with the deposition height. The maximum stress occurs at both ends of the interface between the part and substrate, while the second largest stress occurs near the top center of the part. The residual stress increases with the laser power, with the maximum equivalent stress increasing by 21.79 per cent as the laser power increases from 250 to 450 W. The residual stress decreases with an increase in scan speed with a reduction in the maximum equivalent stress of 13.67 per cent, as the scan speed increases from 500 to 1,000 mm/s. The residual stress decreases with an increase in layer thickness, and the maximum equivalent stress reduces by 33.12 per cent as the layer thickness increases from 20 to 60µm.

The residual stress distribution and effect of process parameters on the residual stress of SLMed Inconel 718 thin-walled part are investigated in detail. This study provides a better understanding of the residual stress in SLM and constructive guidance for process parameters optimization.

This paper aims to analyse the conceptual bases of the related terms of “host” and “guest” in Chinese and reveal essential, though overlooked, cultural differences that relate to “hospitality” in Western and Chinese cultural contexts.

A presupposition of this conceptual investigation is that culture manifests itself linguistically. The analytic approach used here is textual analysis. Confucian classical texts are the main source of evidence for examining the conceptual commitments of the Chinese characters 主 and 客 and their corresponding practical expressions.

Cross-cultural comparison reveals asymmetries between the term “hospitality” and its Chinese translations, etymologically and culturally. This study demonstrates how the Chinese 主–客 paradigm is both hierarchal in nature and centred on the role and interests of the host. It further compares this paradigm with its Western counterpart along five different dimensions.

The specific Chinese norms for the host–guest paradigm synthesized here could prompt both academicians and operators to question the cultural attachments associated with hospitality by participants and the cultural differences in hospitality transactions and management. The cultural sensitivity modelled here is intended to facilitate harmony between a hospitality setting and the culture in which it is embedded.

This conceptual paper is the first in the Anglophone literature to explore the Chinese cultural roots of the concepts “host” and “guest”. The linguistic perspective used in this study allows the concept of “hospitality” to be studied cross-culturally and in an interdisciplinary way, addressing a blind spot in the extant hospitality literature.

Online reviews have become increasingly important and numerous studies have noted the effect of social factors on the review provision of users. The purpose of this study is to investigate how hometowner contributions, which are defined as prior reviews posted by users from the same city, affect the quality of reviews by focal users.

Based on the theories of competitive altruism, pure altruism and reciprocity, as well as several social influence theories, a conceptual framework is constructed to explain user contribution behavior. In addition, empirical models are established based on 831,737 reviews of 919 hotels on Tripadvisor.

The quality of reviews by hometowners can significantly motivate subsequent users to contribute high-quality reviews. This positive effect is stronger than the effect of previous contributions by non-hometowners. The effect of hometowner contribution is amplified in users with limited review-posting experience and/or in those from countries with a considerable cultural distance from the target destination.

This study provides the hospitality literature with new insights into the effect of social factors on the review provision of users in the context of online hotel review websites. The results also present numerous practical implications for online travel communities.

This study is an early attempt to analyze the effect of prior hometowner contributions on the subsequent contribution decisions of focal users. Thus, this study provides a satisfactory starting point for determining whether the review provision of focal users can be affected differently by prior contributions from their peers from different categories.

This study aims to develop a numerical identification and characterization of crack propagation through the use of a new optimization metaheuristics called Lichtenberg optimization.

The damage-identification problem is treated as an inverse problem, which combines finite element methods with intelligent computational methods to obtain the best possible response. To optimize the objectives, the Lichtenberg algorithm is applied, which includes concepts of random cluster growth in nature.

The simulations show that it is possible to determine the Lichtenberg spectrum algorithm a part of the structure to be removed and replaced in this case to stop the propagation.

The results show a very good crack identification in plates-like structures using the Lichtenberg algorithm (LA) based only in strain fields. Although many studies have reported on damage-identification-based optimization methods, very few have focused on the crack tip modeling and LA as the main solver.

This rejoinder aims to critique some of the perspectives in Chen’s (2018) study on hospitality and host–guest paradigm in China.

In this preliminary probe into Chen’s study, critical analysis is performed on Chen’s approaches, whereas document analysis is applied to the relevant ancient Chinese writings. Translations are the author’s own unless indicated otherwise.

Chen’s views are problematic and supported by patchy evidence. “Hierarchy principle” and “host-centric foundation” do not hold up. In a series of asymmetrical comparisons, Chen goes a bit too far in arguing for uniqueness.

This rejoinder presents valid critiques of Chen’s study, thus directing future research in the right direction. It is of some significance to clarify Chen’s misrepresentations and offer a truer and fuller account of Chinese hospitality, given the difficulty for international scholars to validate Chen’s views because of language barrier and cultural unfamiliarity.

The purpose of this paper is to investigate the effect of the Q‐switching parameters on the sintering behavior of laser micro sintering Cu‐based metal powder, using Q‐switched 1064 nm Nd‐YAG laser.

An experimental study has been performed. Metal powder mixture with Cu and Cu‐P alloy powders has been utilized. Q‐switching duration of 15 μs∼25 μs, rate of 25 kHz∼45 kHz have been used.

The results show that as the Q‐switching rate and duration increases, the peak laser power decreases and the densification enhances. However, an optimal peak laser power exists and if the peak laser power is too low, the density of the sample is also low. The densification regime of laser micro‐sintering is not only caused by the liquid phase filling the pores, but is also caused by the Cu powder migrating and by coalescence, e.g. including initial stage and intermediate stage of the traditional furnace liquid phase sintering. However, the degree of these stages depends on the peak power and input laser energy.

The effect of the Q‐switching parameters on sintering behavior of laser micro sintering Cu‐based metal powder using Q‐switched 1064 nm Nd‐YAG laser has been obtained. It is found that the densification behavior is Q‐switching parameters dependent, although the average laser power is same. The densification regime of laser micro‐sintering includes initial stage and intermediate stage of the traditional furnace liquid phase sintering, but the degree is Q‐switching parameters dependent.