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The purpose of this paper is to study the tribology behavior of steel–steel contact under the lubrication of water-based drilling mud with different oleic acid-filled microcapsules as lubricant additives.

A ball-on-disc tribometer was used to evaluate the lubrication properties of the steel–steel contact. The wear tracks of the worn surfaces were observed by a scanning electron microscope.

Results show that the dependence of both friction and wear on the category of additives shares a consistent pattern. In contrast to oleic acid and empty microcapsules, oleic acid-filled microcapsules achieve the best tribological performance which is related to the lubricant effect of oleic acid and the isolation and rolling abilities of microcapsules.

This study provides a helpful method of encapsulated lubricant additives to prolong lubrication performance for steel–steel contact.

This study has applied microcapsules to improve the tribological properties of drilling mud.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2019-0320/

Seasonal fluctuation interference often affects the relational analysis of economic time series. The main purpose of this paper is to propose a new grey relational model for relational analysis of seasonal time series and apply it to identify and eliminate the influence of seasonal fluctuation of retail sales of consumer goods in China.

First, the whole quarterly time series is divided into four groups by data grouping method. Each group only contains the time series data in the same quarter. Then, the new series of four-quarters are used to establish the grey correlation model and calculate its correlation coefficient. Finally, the correlation degree of factors in each group of data was calculated and sorted to determine its importance.

The data grouping method can effectively reflect the correlation between time series in different quarters and eliminate the influence of seasonal fluctuation.

In this paper, the main factors influencing the quarterly fluctuations of retail sales of consumer goods in China are explored by using the grouped grey correlation model. The results show that the main factors are different from quarter to quarter: in the first quarter, the main factors are money supply, tax and per capita disposable income of rural residents. In the second quarter are money supply, fiscal expenditure and tax. In the third quarter are money supply, fiscal expenditure and per capita disposable income of rural residents. In the fourth quarter are money supply, fiscal expenditure and tax.

This paper successfully realizes the application of grey relational model in quarterly time series and extends the applicable scope of grey relational model.

This study aims to explore the structural relationship among food quality, usefulness, ease of use, convenience, brand trust and willingness to pay. The technology acceptance model was used as the theoretical foundation of this work.

Amazon Mechanical Turk was used to recruit survey participants, and 436 valid observations were ultimately used for the analysis. In the data analysis, the structural relationships between variables were explored through structural equation modeling.

The results of hypothesis testing show that ease of use positively affects the usefulness of the Starbucks mobile application. Usefulness also exerts positive impacts on both brand trust and convenience. Moreover, brand trust is positively associated with food quality. Finally, willingness to pay is positively influenced by both convenience and brand trust.

This study contributes to the literature by not only validating the technology acceptance model using the Starbucks mobile application but also proposing food quality-related attributes in the domain of the café business.

The primary goal of this article is to review the existing studies and offer clarity regarding the association between social media adoption and youth civic engagement.

This research systematically summarizes and reviews 42 original articles published from 2010 to 2019 with an objective of offering insightful results. Additionally, a theoretical framework was carefully designed by adopting various conceptions from citizen participation and computer-mediated communication research literature.

The findings demonstrate that social media usage could generally have a positive correlation with civic participation among younger generations. Moreover, the result also highlights that certain functional features of social media uses including using social media for news consumption and expression could significantly predict civic engagement.

Despite the ever-growing importance of social media technologies, investigations on their differential, nonlinear and even inconsistent effects on civic engagement remain theoretically ambiguous and empirically unsubstantiated. The study represents one of the first scholarly attempts to review, summarize and analyze the extant research evidence from the past ten years.

The purpose of this study is to identify the attributes that statistically affect reason intention. The triple bottom line, a theoretical framework of corporate social responsibility (CSR) consisting of economic, social and environmental subdimensions, is used as the theoretical foundation.

In this study, price fairness, quarantine and hygiene, and eco-friendliness represent economic, social and environmental CSR, respectively. Amazon Mechanical Turk is used for data collection. The valid number of observations is 474. Structural equation modeling is implemented to test the research hypotheses.

The results indicate that price fairness, quarantine and hygiene positively affect the reuse intention of coffee shops. However, eco-friendliness appears to be an attribute that does not significantly affect reuse intention.

This study theoretically contributes to the literature by demonstrating the explanatory power of triple bottom line theory for café customer intention.

This paper aims to investigate how brand identity is co-created, with a specific focus on how employees contributed to the process in a five-star hotel setting. The focus of this study is on understanding how two hotels planned and executed their brand identity strategy simultaneously, differentiating one from the other and how employees actively participated in this process.

A longitudinal case study approach was adopted, centred on building the identity of two luxury hotels owned by a single company in Seoul, Korea. Various organizational documents were collected and analyzed to understand the brand identity of the hotels and how brand co-creation has been implemented. In addition, semi-structured in-depth interviews were conducted with 42 employees to understand the brand co-creation process from their perspective.

The brand co-creation process of the hotels was conducted simultaneously and evolved over the following four phases, with employees’ roles varying in each phase, namely, establishing a clear brand identity strategy; designing and selecting sensory identity; aligning organizational identity; and delivering brand identity through external communication. Employees that participated in brand co-creation enhanced their brand knowledge, developed emotional bonds with the brand and were motivated to deliver the brand identity. Furthermore, those that immersed themselves in the new brand identities were able to enable positive guest perceptions towards the brand image, which consequently enhanced employees’ pride in their work.

This research advances the brand management literature in defining branding and brand identity elements, as well as emphasizing the importance of consistent branding. In addition, the current study expands the scope of internal branding, highlighting the process of brand co-creation and the role of employees as active participants. Moreover, it reveals that employees’ participation enhances not only their brand knowledge but also their emotional bonds with the brand. The proposed conceptual framework demonstrates the flow of branding elements, brand identity elements and the “infinite loop” of employee participation in brand co-creation.

The case study approach adopted here enables an in-depth investigation of employee participation in brand co-creation, including their different roles and activities in the process; a phenomenon that has not been adequately explored in previous research.

This paper develops a framework for selecting the most efficient and effective preventive maintenance policy using multiple-criteria decision making and multi-objective optimization.

The critical component is identified with a list of maintenance policies, and then its failure data are collected and the optimization objective functions are defined. Fuzzy AHP is used to prioritize each objective based on the experts' questionnaire. Weighted comprehensive criterion method is used to solve the multi-objective models for each policy. Finally, the effectiveness and efficiency are calculated to select the best maintenance policy.

For a fleet of buses in hot climate environment where coolant pump is identified as the most critical component, it was found that block-GAN policy is the most efficient and effective one with a 10.24% of cost saving and 0.34 expected number of failures per cycle compared to age policy and block-BAO policy.

Only three maintenance policies are compared and studied. Other maintenance policies can also be considered in future.

The proposed methodology is implemented in UAE for selecting a maintenance scheme for a critical component in a fleet of buses. It can be validated later in other Gulf countries.

This research lays a solid foundation for selecting the most efficient and effective preventive maintenance policy for different applications and sectors using MCDM and multi-objective optimization to improve reliability and avoid economic loss.

Additive manufacturing based on arc welding is a fast and effective way to fabricate complex and irregular metal workpieces. Thin-wall metal structures are widely used in the industry. However, it is difficult to realize support-free freeform thin-wall structures. This paper aims to propose a new method of non-supporting thin-wall structure (NSTWS) manufacturing by gas metal arc welding (GMAW) with the help of a multi-degree of freedom robot arm.

This study uses the geodesic distance on the triangular mesh to build a scalar field, and then the equidistant iso-polylines are obtained, which are used as welding paths for thin-wall structures. Focusing on the possible problems of interference and the violent variation of the printing directions, this paper proposes two types of methods to partition the model mesh and generate new printable iso-polylines on the split meshes.

It is found that irregular thin-wall models such as an elbow, a vase or a transition structure can be deposited without any support and with a good surface quality after applying the methods.

The experiments producing irregular models illustrate the feasibility and effectiveness of the methods to fabricate NSTWSs, which could provide guidance to some industrial applications.

Generating an in-depth understanding of information needs and seeking behaviour is important both for restructuring existing agricultural information systems (ISs) and for creating new ISs. Many information seeking models have been developed over the years, most are narrowly focused on a specific role or discipline. However, no such specific model has been developed in reference to agriculture or an allied discipline. Thus, the purpose of this paper is to develop a model to explore the information seeking behaviour (ISB) of farmers.

The model proposed in this paper is based on Wilson’s model. The theoretical insights and empirical evidences comprehended at the study were embedded into Wilson’s model to develop a model that explores the ISB of farmers. The proposed model was quantitatively evaluated using empirical data gathered through a survey of 289 farmers. Furthermore, the model was qualitatively evaluated by subject experts against criteria of simplicity, comprehensiveness, exactness, generality and clarity.

The key finding of this study is the model developed to explore the ISB of farmers. The adapted model provides theoretical and empirical bases for exploring farmers’ ISBs. Thus, the model will be useful in developing valuable design insights to apply to user-centred agricultural ISs.

The originality of this study relates to its demonstration of how existing models can be reconsidered and adapted based on related literature and then tested and presented as adapted models. The proposed model will be useful to promote informational studies in agriculture.

The purpose of this study was to prepare carboxylated attapulgite (APT-COOH) and then be used as one of the ligands to prepare metal organic framework (MOF) hybrid materials to reduce the cost of MOF materials and improve the dispersed condition of APT. And then the materials were used to enrich anionic dye Congo red from aqueous solution.

The MOF hybrid materials were designed by means of facile reflux method rather than hydrothermal method, characterized by Thermogravimetric Analysis (TGA), Fourier Transform Infrared (FTIR) Spectrometer and pore structure. The dispersed degree of APT-COOH in the MOF materials was validated according to adsorption efficiency for Congo red.

Due to introduction of APT-COOH, the microenvironment of the MOF materials changed, leading to different adsorption behaviors. Compared to the MOF material without APT-COOH, the adsorption capacities of the hybridized MOF materials with different amounts of APT-COOH introduced increased by 4.58% and 15.55%, respectively, as the initial concentration of Congo red solution of 300 mg/L. Meantime, hybridized MOF materials were suitable to remove Congo red with low concentration, while the MOF material without APT-COOH was appropriate to enrich Congo red with high concentration.

The microstructure of MOF hybrid materials in detail is the further and future investigation.

This study will provide a method to reduce the cost of MOF materials and a theoretical support to treat anionic dyes from aqueous solution.

APT-COOH was prepared and used as one of the ligands to synthesize MOF material to improve the dispersed degree of APT-COOH and reduce the cost of the MOF materials. The adsorption efficiency was greatly enhanced with low concentration of Congo red solution, and the results indicated that hydrogen bonding, electrostatic interaction, and p-p conjugation were involved in the adsorption process. The prepared MOFs materials exhibited excellent adsorption efficiency, which made the present materials highly promising and potentially useful in practical application as adsorbents to enrich anionic dyes such as Congo red from aqueous solution.