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The maintenance of the air–water interface is crucial for the drag reduction on hydrophobic surfaces. But the air bubbles become unstable and even washed away under high speed flow, causing the failure of surface hydrophobicity. Thereby, this paper aims to understand the relations between bubble behaviors and surface properties, flow conditions and to discover new methods to maintain the air–water interface.

Bubble properties on hydrophobic surfaces were characterized using single-component multiphase lattice Boltzmann simulation. Three equations of state (EOSs), including the Peng–Robinson, Carnahan–Starling and modified Kaplun–Meshalkin EOSs, were incorporated to achieve high density ratios.

Both the static and dynamic properties of bubbles on hydrophobic surfaces were investigated and analyzed under different flow conditions, solid–liquid interactions and surface topology.

By revealing the properties of bubbles on hydrophobic surfaces, the effects of flow conditions and surface properties were characterized. The maintenance method of air–water interface can be proposed according to the bubble properties in the study.

Oppositional brand loyalty (OBL) has become widespread and has thus received growing scholarly attention in recent years. Although opposition behaviors have distinct manifestations, their differential antecedents remain underexplored. Drawing from the identity-based motivation model, this article aims to examine the impact of brand identification and brand disidentification on the two distinct dimensions of OBL (i.e. brand avoidance and trash talk) according to their different intensity and activation levels (passive or active). In addition, article aims to examine the moderating role of perceived inter-group rivalry.

The authors collected survey data and obtained 392 valid questionnaires from smartphone users. Structural equation modeling was used for hypothesis testing.

The results show that brand identification has a significant positive effect on avoidance of rival brands, but not on trash talk; brand disidentification has a significant positive effect on both avoidance and trash talk of rival brands; and perceived inter-group rivalry positively moderates the relationship between brand disidentification and trash talk, but does not alter the relationship between brand disidentification and brand avoidance.

This study extends the literature on OBL by investigating differential antecedents of two distinct dimensions of brand opposition. It provides more complete understanding of the formation of OBL by examining the role of users’ relationship with a focal brand, its competing brand and inter-group relationship.

The purpose of this paper is to address the research question of how human actors and technology interact together in practices in the context of a sharing economy. The theoretical foundation of this paper is based on the existing literature about the sharing economy and studies that have been carried out examining value co-creation and sociomateriality.

This paper adopts a qualitative case study method for the empirical investigation. Using theoretical sampling, Xbed, an internet, unmanned and self-service hotel platform based in Guangzhou, China, was chosen for the empirical investigation. The case was built on multiple sources of data, including archival materials, on-site fieldwork and in-depth interviews. Then, the case was interpreted based on a number of theoretical concepts, with a particular emphasis on the sociomaterial perspective.

This paper shows how human actors and technology interact with one another in a number of interrelated ways, which collectively result in the value co-creation necessary for creating a sharing economy. The authors have found that various forms of sociomateriality (the intersection between technology, work and organization) play a key role in co-creation and that interactions between these sociomaterial assemblages (assemblage-to-assemblage (A2A)) drive the development of a sharing economy. These sociomaterial assemblages have dynamic and evolving characteristics.

The authors argue that the key to the success of a sharing economy lies in how to engage participating actors with material entities (e.g. technology applications) to form action-enabling sociomaterial assemblages, as well as in determining how these assemblages can be systematically arranged to collectively form a larger assemblage. We suggest that managers need to conceive how relations between the social and the material realms can be structured by adopting a service logic that aims to help the beneficiary function better. The authors also suggest that managers have to consider what assemblages are necessary and how they are connected, to construct a full access-based service.

This paper conceptualizes the sharing economy as a system of value co-creation practices and empirically examines such practices from a sociomaterial perspective. This paper adopts the concept of sociomaterial assemblages to investigate sharing practices, through which the knowledge of the role of technology in the development of a sharing economy is enhanced. This paper also expands the knowledge of service-dominant logic by using a microfoundation perspective to look at the value co-creation that emerges as a result of the interaction between sociomaterial assemblages. These assemblages also act as constitutive elements of a service ecosystem.

This paper aims to explore whether or not and how brand community supportive climates (information- versus emotion-supportive climates) have an impact on consumer-to-consumer helping behavior.

A survey of users of cell phone brand communities was conducted, and data from 413 participants were used to validate the hypotheses of this study.

Results indicated that emotion- and information-supportive climates enhance consumer-to-consumer helping behavior through consumer–community relationships (i.e. brand community identification and brand community commitment).

To enhance the external validity of this research, future studies could investigate other settings (e.g. social media-based brand communities and brands of other product types) in countries with different religious beliefs.

Marketers should create an environment where consumers feel informationally and emotionally supported within the brand community, thereby enabling the former to enhance their relationships with their brand communities and ultimately increase consumers' helping behavior.

By dividing the supportive climate into two parts, the current study enriched the literature on community climate. Moreover, the authors complemented and expanded the literature on consumer helping behavior.

Users' knowledge sharing provides valuable resources for brand community participants and is, therefore, critical for the viability of virtual brand communities. Drawing from both self-determination theory (SDT) and psychological ownership theory, the paper aims to investigate the impact of fulfillment of three basic psychological needs on brand users' knowledge-sharing behavior and examines psychological ownership as a mediator.

Survey data consisting of 316 valid responses were collected from users of Huawei Pollen Club Community. Confirmatory factor analysis (CFA) confirmed the reliability and validity of measures, and hierarchical linear regression and bootstrapping were used to test all hypotheses.

Fulfillment of the need for autonomy, relatedness and competence in a virtual brand community boosts users' psychological ownership and has a positive influence on their knowledge-sharing behavior. Furthermore, psychological ownership partially mediates the relationships between the fulfillment of psychological needs and knowledge-sharing behavior. In addition, the authors found that when users participate in more offline brand activities, the positive impact of the fulfillment of the need for relatedness on psychological ownership is strengthened, while the positive impact of the fulfillment of the need for autonomy on psychological ownership is weakened.

The paper contributes to the existing literature by exploring the relationships between fulfilling users' three basic psychological needs and their knowledge-sharing behavior through the mediating role of psychological ownership. The authors also provide insight into how offline brand activities interact with the fulfillment of psychological needs in virtual brand communities.

Partial alignment for 3 D point sets is a challenging problem for laser calibration and robot calibration due to the unbalance of data sets, especially when the overlap of data sets is low. Geometric features can promote the accuracy of alignment. However, the corresponding feature extraction methods are time consuming. The purpose of this paper is to find a framework for partial alignment by an adaptive trimmed strategy.

First, the authors propose an adaptive trimmed strategy based on point feature histograms (PFH) coding. Second, they obtain an initial transformation based on this partition, which improves the accuracy of the normal direction weighted trimmed iterative closest point (ICP) method. Third, they conduct a series of GPU parallel implementations for time efficiency.

The initial partition based on PFH feature improves the accuracy of the partial registration significantly. Moreover, the parallel GPU algorithms accelerate the alignment process.

This study is applicable to rigid transformation so far. It could be extended to non-rigid transformation.

In practice, point set alignment for calibration is a technique widely used in the fields of aircraft assembly, industry examination, simultaneous localization and mapping and surgery navigation.

Point set calibration is a building block in the field of intelligent manufacturing.

The contributions are as follows: first, the authors introduce a novel coarse alignment as an initial calibration by PFH descriptor similarity, which can be viewed as a coarse trimmed process by partitioning the data to the almost overlap part and the rest part; second, they reduce the computation time by GPU parallel coding during the acquisition of feature descriptor; finally, they use the weighted trimmed ICP method to refine the transformation.

The purpose of this paper is to develop an automatic disassembly navigation approach for human interactions in the virtual environment to achieve accurate and effective virtual assembly path planning (VAPP).

First, to avoid the error-prone human interactions, a constraint-based disassembly method is presented. Second, to automatically provide the next operable part(s), a disassembly navigation mechanism is adopted. Finally, the accurate assembly path planning can be obtained effectively and automatically by inversing the ordered accurate disassembly paths, which are obtained interactively in the virtual environment aided with the disassembly navigation matrix.

The applications present that our approach can effectively avoid the error-prone interactive results and generate accurate and effective VAPP.

There are several works that could be conducted to make our approach more general in the future: to further study the basic disassembly direction deducing rules to make the process of determining disassembly direction totally automatic, to consider the hierarchy of the parts in virtual reality system and to consider the space for assembly/disassembly tools or operators.

The approach has the following characteristics: a new approach to avoid the error-prone human interactions for accurate assembly path planning obtaining, a new constraint deducing method for determining the disassembly semantics automatically or semi-automatically is put forward and a new method for automatically identifying operable parts in VAPP is set forward.

Time slot allocation in world interoperability for microwave access (WiMax) mesh networks is controlled by a centralized scheduling algorithm, as specified in the IEEE standard 802.16. The scheduling algorithm should be able to minimize the total transmission time for all traffic flows. The purpose of this paper is to investigate the multi‐channel scheduling problem in WiMax mesh networks, in order to explore the potential of simultaneous transmissions and thus minimize the total transmission time.

The paper first analyzes how many channels are sufficient for the avoidance of interference, then presents an efficient scheduling algorithm along with the channel assignment strategy for time slot allocation. Particularly, for networks with chain topology, the paper provides an optimal solution to minimize the total transmission time.

The simulation results show that this scheme can improve the system performance substantially as compared with the single‐channel system. Also, it is observed that double‐channel settings may provide a performance similar to the multiple channels.

The algorithm presented in this paper is conformed to the IEEE standard 802.16‐2004; so it is suitable for WiMax mesh networks.

The paper is of value in presenting a scheduling and channel assignment schema for multi‐channel WiMax mesh networks. The work is also important for the study of time division multiple access (TDMA)‐based multi‐channel wireless mesh networks.

The purpose of this paper to describe the research work on the long‐term preservation of Chinese digital information funded by National Natural Science Foundation of China (NSFC) since 2001.

The paper provides an overview, in text and figures, of ways in which e‐documents originating in China, in now obsolete formats, can be made readable again. Also, results of a recent survey of electronic records management in government and corporations are given.

The lifecycle management gap with respect to electronic records is highlighted and the main factors that restrict the Chinese anti‐disaster data backup plan are analysed. It is suggested that the data backup centre which can be accepted by small medium enterprises should be the e‐government disaster recovery centre for local government.

All the research results are useful for those who need to understand the long‐term preservation of Chinese digital information and electronic records management.

Compared with the time-consuming numerical method and the complex lumped parameter thermal network method to solve the steady-state heat distribution of the permanent magnet (PM) linear motor, there is no analytical method based on the thermal partial differential equations. This paper aims to propose a two-dimensional (2-D) analytical model for predicting the steady-state temperature distribution of PM linear motors to improve the prediction accuracy and speed up the calculation.

Based on the complex Fourier series theory and Cauchy’s product theorem, this paper presents for the first time a general analytical solution for 2-D temperature field in Cartesian coordinates. Then, by combining the electromagnetic field finite element model (FEM), the copper loss, iron loss and PM eddy current loss are used as the heat sources of the thermal analytical model. Finally, the solution to the temperature field is obtained by solving the system equations under boundary and interface conditions.

The analytical results are in good agreement with those from the thermal FEM, and the calculation speed is significantly faster than that of the thermal FEM.

The multilayer model proposed in this paper can consider heat conduction, convection and radiation. It is not only suitable for PM linear motors but also has significant application value for the thermal analysis of electromagnetic devices modeled in 2-D Cartesian coordinates.