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This paper aims to reveal the tribochemical reaction mechanism on the nano-cutting interface between HMX crystal and diamond tool.

Molecular dynamics simulation of HMX crystal nano-cutting by the reactive force field is carried out in this paper. The affinity of activated atoms and friction damage at the different interface have been well identified by comparing two cutting systems with diamond tool or indenter. The analyses of reaction kinetics, decomposition products and reaction pathways are performed to reveal the underlying atomistic origins of tribocatalytic reaction on the nano-cutting interface.

The HMX crystals only undergo damage and removal in the indenter cutting, while they appear to accelerate thermal decomposition in the diamond cutting. the C-O affinity is proved to be the intrinsic reason of the tribocatalytic reaction of the HMX-diamond cutting system. The reaction activation energy of the HMX crystals in the diamond cutting system is lower, resulting in a rapid increase in the decomposition degree. The free O atoms can induce the asymmetric ring-opening mode and change the decomposition pathways, which is the underlying atomistic origins of the thermal stability of the HMX-diamond cutting system.

This paper describes a method for analyzing the tribochemical behavior of HMX and diamond, which is beneficial to study the thermal stability in the nano-cutting of HMX.

The purpose of this paper is to focus on the design of automated fabric defect detection based on cascaded low-rank decomposition and to maintain high quality control in textile manufacturing.

This paper proposed a fabric defect detection algorithm based on cascaded low-rank decomposition. First, the constructed Gabor feature matrix is divided into a low-rank matrix and sparse matrix using low-rank decomposition technique, and the sparse matrix is used as priori matrix where higher values indicate a higher probability of abnormality. Second, we conducted the second low-rank decomposition for the constructed texton feature matrix under the guidance of the priori matrix. Finally, an improved adaptive threshold segmentation algorithm was adopted to segment the saliency map generated by the final sparse matrix to locate the defect regions.

The proposed method was evaluated on the public fabric image databases. By comparing with the ground-truth, the average detection rate of 98.26% was obtained and is superior to the state-of-the-art.

The cascaded low-rank decomposition was first proposed and applied into the fabric defect detection. The quantitative value shows the effectiveness of the detection method. Hence, the proposed method can be used for accurate defect detection and automated analysis system.

The purpose of this paper is to find an efficient fabric defect detection algorithm by means of exploring the sparsity characteristics of main local binary pattern (MLBP) extracted from the original fabric texture.

In the proposed algorithm, original LBP features are extracted from the fabric texture to be detected, and MLBP are selected by occurrence probability. Second, a dictionary is established with MLBP atoms which can sparsely represent all the LBP. Then, the value of the gray-scale difference between gray level of neighborhood pixels and the central pixel, and the mean of the difference which has the same MLBP feature are calculated. And then, the defect-contained image is reconstructed as normal texture image. Finally, the residual is calculated between reconstructed and original images, and a simple threshold segmentation method can divide the residual image, and the defective region is detected.

The experiment result shows that the fabric texture can be more efficiently reconstructed, and the proposed method achieves better defect detection performance. Moreover, it offers empirical insights about how to exploit the sparsity of one certain feature, e.g. LBP.

Because of the selected research approach, the results may lack generalizability in chambray. Therefore, researchers are encouraged to test the proposed propositions further.

In this paper, a novel fabric defect detection method which extracts the sparsity of MLBP features is proposed.

The purpose of this paper is to study the transition process from the crystalline particles appearing before the pump inlet to the stable operation of the pump.

Firstly, a modeling test method was put forward for the high-temperature molten salt pump. Then, according to a modeling test scheme, the experiment of the solid–liquid two-phase flow was carried out by using a model pump similar to the prototype pump. Meanwhile, the numerical method to simulate the transition process of a molten salt pump was studied, and the correctness of the numerical model was verified by the experimental results. Finally, the transition process of the molten salt pump was studied by the verified numerical model in detail.

In the simulation of the transition process, it is more accurate to judge the end of the transition process based on the unchanged particle volume fraction (PVF) at the pump outlet than on the periodic fluctuation of the outlet pressure. The outlet pressure is closely related to the PVF in the pump. The variation of the outlet pressure is slightly prior to that of the PVF at the pump outlet and mainly affected by the PVF in the impeller and volute. After 0.63 s, the PVF at each monitoring point changes periodically, and the time-averaged value does not change with time.

This study is of great significance to further improve the design method of molten salt pump and predict the abrasion characteristic of the pump due to interactions with solid particles.

A numerical method is established to simulate the transition process of a molten salt pump, and a method is proposed to verify the numerical model of two-phase flow by modeling test.

The paper aims to provide a response to commentaries in this issue by Andrew Sayer, and Robert W. Scapens and ChunLei Yang on “Case studies and differentiated realities” a paper by Sue Llewellyn published in Qualitative Research in Accounting & Management Vol. 4 No. 1, 2007.

Discusses issues raised in the commentaries around “differentiated realities”, “pluralist ontology” and the “single reality” of social constructivism.

Reiterates an understanding of the idea of “differentiated realities” and discusses the methodological implications that arise from it.

Clarifies Llewellyn's original discussion of differentiated realities and case studies.

No study to date has addressed the construct of event tourist experience value and there is no well-accepted value measurement method. This study aims to examine the underlying dimensions of event tourist experience value from a holistic perspective.

The research process consists of two steps. First, the dimensions of event tourist experience value are investigated by using grounded theory and content analysis of travel blogs. The second step is to explore and verify the scale of event tourist experience value.

The items show that event tourist experience value can be comprehensively understood from three dimensions: functional value (functional factors); hedonic value (relaxation, escape, restoration and interaction); and symbolic value (social prestige, belonging and self-transcendence).

The findings are useful indicators explaining events attendance, and can help event organizers and destination managers to better understand the needs of tourists and design event experiences in a more sophisticated way.

This work integrates a series of varied events to suggest a holistic view of event tourist experience value, which provides a theoretical basis for other scholars to compare and monitor findings in this field.

This study aims to examine the development of a social enterprise in China’s tourism industry by analyzing the coevolution of the social entrepreneur and the social system.

Purposeful sampling was used to select 1kg.org as a single-case study. Semistructured in-depth interviews of three informants were conducted to obtain organization-specific insights. Interview data were analyzed following structuration theory. Secondary data and interviews of other social entrepreneurs and experts were used to support the findings. Research findings were validated using triangulation and member-checking methods.

Because of the institutional environment, most nonprofit organizations in China do not have resource independence and clear legal identity. Meanwhile, social enterprise has emerged as a new organizational form with the objective of creating social value through profitable business operations.

Social enterprise is still in its infancy in China, particularly in the tourism field. This study reveals an innovative and sustainable model for nonprofit organizations in China facing institutional challenges and competitive funding environments. It provides recommendations to policymakers for improving mechanisms to increase social services through social enterprises.

This study proposes a new conceptual framework for studying social entrepreneurship by adapting structuration theory to address contemporary social and business issues.

The purpose of this paper is to propose a prediction method of gas-liquid two-phase flow patterns and reveal the flow characteristics in the suction chamber of a centrifugal pump.

A transparent model pump was experimentally studied, and the gas-liquid two-phase flow in the pump was numerically simulated based on the Eulerian–Eulerian heterogeneous flow model. The numerical simulation method was verified from three aspects: the flow pattern in the suction chamber, the gas spiral length and the external characteristics of the pump. The two-phase flow in the suction chamber was studied in detail by using the numerical simulation method.

There are up to eight flow patterns in the suction chamber. However, at a certain rotational speed, only six flow patterns are observed at the most. At some rotational speeds, only four flow patterns appear. The gas spiral length has little relationship with the gas flow rate. It decreases with the increase of the liquid flow rate and increases with the increase of the rotational speed. The spiral flow greatly increases the turbulence intensity in the suction chamber.

A method for predicting the flow pattern was proposed. Eight flow patterns in the suction chamber were identified. The mechanism of gas-liquid two-phase flow in the suction chamber was revealed. The research results have reference values for the stable operation of two-phase flow pumps and the optimization of suction chambers.

This paper aims to prevent gasket sealing failure in engineering, accurately predict gasket life, extend system life and improve sealing reliability. The accelerated life test method of flexible graphite composite–reinforced gaskets is established, the life distribution law of flexible graphite composite–reinforced gaskets is revealed, and the life prediction method of flexible graphite composite–reinforced gaskets with different allowable leakage rates is proposed, which can provide a reference for the life prediction of other types of gaskets.

In this study, flexible graphite composite–reinforced gaskets were tested for long-term high-temperature sealing performance on a multi-sample gasket accelerated life test rig. The data were also analyzed using the least squares method and the K-S hypothesis calibration method. A gasket time-dependent leakage model and an accelerated life model were also developed. Constant stress-accelerated life tests were conducted on flexible graphite composite–reinforced gaskets. On this basis, a gasket life prediction method at different allowable leakage rates was proposed.

The life distribution law of flexible graphite composite–reinforced gaskets is revealed. The results show that the life of the gasket obeys the Weibull distribution. The time-correlated leakage model and accelerated life model of the gasket were established. And the accelerated life test method of the flexible graphite composite–reinforced gasket was established. The life distribution parameters, accelerated life model parameters and life estimates of gaskets were obtained through tests. On this basis, a gasket life prediction method under different leakage rates was proposed, which can be used as a reference for other types of gaskets.

The research in this paper can better provide guidance for the use and replacement of gaskets in the project, which is also very meaningful for predicting the leakage condition of gaskets in the bolted flange connection system and taking corresponding control measures to reduce energy waste and pollution and ensure the safe operation of industrial equipment.

A multi-specimen gasket-accelerated life test device has been developed, and the design parameters of the device have reached the international advanced level. The life distribution law of the flexible graphite composite–reinforced gasket was revealed. The accelerated life test method for the flexible graphite composite–reinforced gasket was established. The life prediction method of the flexible graphite composite–reinforced gasket under different allowable leakage rates was proposed.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2023-0254/

Although collaborative research is believed to be an important means of accessing external knowledge, research on whether taking a strategic network position benefits new product development (NPD) is inconclusive. This study aims to unravel the conditions under which taking a strategic position within a collaborative research network is conducive for a firm’s NPD.

Drawing on social network theory, absorptive capacity theory and knowledge recombinant studies, this study examines how strategic network positions (i.e. degree centrality and structural holes) and knowledge base cohesion (i.e. local and global cohesion) in tandem affect a firm’s NPD. A panel data set of 366 firms in the Chinese automobile sector (2002–2010) is empirically analyzed, using the panel negative binomial approach with random effects and several alternate estimation approaches.

This study reveals that, rather than the volume of a firm’s knowledge base, its cohesion determines how it absorbs and uses knowledge accrued from collaborative research for NPD. Specifically, this paper finds that centrally positioned firms have greater NPD when their knowledge bases are locally cohesive, while firms spanning structural holes have more NPD when their knowledge bases are globally cohesive.

Successfully transferring collaborative research outcomes into product innovation is difficult. This study contributes to the literature on strategic network positions and NPD. The findings advance the understanding of knowledge base cohesion’s moderating role in explaining how firms absorb and exploit external knowledge for internal innovation. The findings also have important implications for managers who wish to promote product innovation by engaging in collaborative research with external partners.