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The purpose of this paper is to investigate the distribution characteristics of airflow in mine ventilation suits with different pipeline structures when the human body is bent at various angles. On this basis, the stress points are extracted to investigate the pressure variation of a ventilation suit under different ventilation rates and pipeline structures.

Based on the three-dimensional human body scanner, portable pressure test and other instruments, a human experiment was conducted in an artificial cabin. The study analyzed and compared the distribution characteristics of clearance under three different pipeline structures, as well as the pressure variation of the ventilation suit.

The study found that the clearance in front of two pipeline structures gradually increased in size as the degree of bending increased, and there was minimal clearance in the chest and back. The longitudinal structure exhibits a significant decrease in clearance compared to the spiral structure. The pressure value of the spiral pipeline structure with the same ventilation volume is low, followed by the transverse structure, while the longitudinal structure has the highest pressure value. The increase in clothing pressure value of a spiral pipeline structured ventilation suit with varying ventilation volumes is minimal.

The ventilation suit has a promising future as a type of personal protective equipment for mitigating heat damage in mines. It is of great value to study the pipeline structure of the ventilation suit for human comfort.

Hospital governance accountability structures in Iran, similar to other countries, have undergone various reforms with different goals. The current study aimed to identify the rules and regulations of the hospital governance structure in Iran and how they pay attention to accountability.

This qualitative document content analysis study was conducted using hospital governance structure documents in Iran using the Ready materials, Extract data, Analyze data and Distil (READ) document analysis framework. 2,921 documents were extracted from the official government websites of Iran. After screening, seven documents related to the hospital governance structure were selected. A directed content analysis approach was used. The findings were finally future purification matched with the original documents.

The findings showed that documents had not addressed the inclusive governance structure of the hospital comprehensively. The medical staff organization structure is not considered in the documents, and its duties are assigned to a technical or a clinical director. Most documents addressed financial accountability. The documents did not require the hospital’s governance to have an inclusive accountability structure. However, they paid more attention to the administrative and financial autonomy of hospitals.

Accountability is one of the most essential components in the hospital's governance structure. It can increase the success of hospital efficiency, effectiveness, vision and mission fulfillment. The study result can help health services policymakers and managers formulate better organization structure rules and regulations for hospital governance accountability.

This study is the first qualitative analysis of accountable governance structure documents in Iranian hospitals. We used the READ method as a comprehensive approach for document analysis.

This study compares the fatigue performance and biocompatibility of as-built and chemically etched Ti-6Al-4V alloys in TPMS-gyroid and stochastic structures fabricated via Powder Bed Fusion Laser Beam (PBF-LB). This study aims to understand how complex lattice structures and post-manufacturing treatment, particularly chemical etching, affect the mechanical properties, surface morphology, fatigue resistance and biocompatibility of these metamaterials for biomedical applications.

Selective Laser Melting (SLM) technology was used to fabricate TPMS-gyroid and Voronoi stochastic designs with three different relative densities (0.2, 0.3 and 0.4) in Ti-6Al-4V ELI alloy. The as-built samples underwent a chemical etching process to enhance surface quality. Mechanical characterization included static compression and dynamic fatigue testing, complemented by scanning electron microscopy (SEM) for surface and failure analysis. The biocompatibility of the samples was assessed through in-vitro cell viability assays using the Alamar Blue assay and cell proliferation studies.

Chemical etching significantly improves the surface morphology, mechanical properties and fatigue resistance of both TPMS-gyroid and stochastic structures. Gyroid structures demonstrated superior mechanical performance and fatigue resistance compared to stochastic structures, with etching providing more pronounced benefits in these aspects. In-vitro biocompatibility tests showed high cytocompatibility for both as-built and etched samples, with etched samples exhibiting notably improved cell viability. The study also highlights the importance of design and post-processing in optimizing the performance of Ti64 components for biomedical applications.

The comparative analysis between as-built and etched conditions, alongside considering different lattice designs, provides valuable information for developing advanced biomedical implants. The demonstration of enhanced fatigue resistance and biocompatibility through etching adds significant value to the field of additive manufacturing, suggesting new avenues for designing and post-processing implantable devices.

Bolted joint is the most important connection method in aircraft composite/metal stacked connections due to its large load transfer capacity and high manufacturing reliability. Aircraft components are subjected to complex hybrid variable loads during service, and the mechanical properties of composite/metal bolted joint directly affect the overall safety of aircraft structures. Research on composite/metal bolted joint and their mechanical properties has also become a topic of general interests. This article reviews the current research status of aeronautical composite/metal bolted joint and its mechanical properties and looks forward to future research directions.

This article reviews the research progress on static strength failure and fatigue failure of composite/metal bolted joint, focusing on exploring failure analysis and prediction methods from the perspective of the theoretical models. At the same time, the influence and correlation mechanism of hole-making quality and assembly accuracy on the mechanical properties of their connections are summarized from the hole-making processes and damage of composite/metal stacked structures.

The progressive damage analysis method can accurately analyze and predict the static strength failure of composite/metal stacked bolted joint structures by establishing a stress analysis model combined with composite material performance degradation schemes and failure criteria. The use of mature metal material fatigue cumulative damage models and composite material fatigue progressive damage analysis methods can effectively predict the fatigue of composite/metal bolted joints. The geometric errors such as aperture accuracy and holes perpendicularity have the most significant impact on the connection performance, and their mechanical responses mainly include ultimate strength, bearing stiffness, secondary bending effect and fatigue life.

Current research on the theoretical prediction of the mechanical properties of composite/metal bolted joints is mainly based on ideal fits with no gaps or uniform gaps in the thickness direction, without considering the hole shape characteristics generated by stacked drilling. At the same time, the service performance evaluation of composite/metal stacked bolted joints structures is currently limited to static strength and fatigue failure tests of the sample-level components and needs to be improved and verified in higher complexity structures. At the same time, it also needs to be extended to the mechanical performance research under more complex forms of the external loads in more environments.

The mechanical performance of the connection structure directly affects the overall structural safety of the aircraft. Many scholars actively explore the theoretical prediction methods for static strength and fatigue failure of composite/metal bolted joints as well as the impact of hole-making accuracy on their mechanical properties. This article provides an original overview of the current research status of aeronautical composite/metal bolted joint and its mechanical properties, with a focus on exploring the failure analysis and prediction methods from the perspective of theoretical models for static strength and fatigue failure of composite/metal bolt joints and looks forward to future research directions.

This study aims to examine how capital structure influences earnings management for firms in the Saudi market, which is influenced by an Islamic environment that discourages excessive borrowing.

This study uses a data set that covers the period from 2013 to 2020 for firms listed on the Saudi Stock Exchange (Tadawul) and uses panel data regression models to test the impact of capital structure on earnings management.

The empirical results reveal that earnings manipulation is less common among firms that have less debt, which implies that firms in the Saudi market face high scrutiny to maintain lower leverage to meet the investment requirements of stakeholders based on religious status, which in turn reduces information asymmetry and constrains opportunistic behaviour in managing earnings.

This study provides insights for regulators, investors, and managers on the role of religion in shaping capital structure and monitoring financial reporting practices. This study recognises that firms’ decision-making can be explained by non-economic motives, such as religion, which can serve as a less costly external mechanism to alleviate agency costs compared to other economic motives.

This study contributes to the literature by exploring how capital structure and earnings management relate to a distinctive and unique Islamic context that remains largely unexamined. This context allows us to investigate this issue by examining how the Islamic environment, which is not driven by economic or legal reasons, affects managers’ choices of capital structure and earnings management. This study reveals how a strong religious setting can shape firms’ choices regarding capital structure and financial reporting practices.

Multilayer composite liner structures are the primary structural form of hydraulic tunnels. However, the bearing mechanism of multilayer composite liners has not been investigated thoroughly. Many existing design schemes do not properly achieve a balance between structural safety, anti-seepage capacity, and cost effectiveness. Thus, a new composite liner structure type and its theoretical model was proposed.

A novel hydraulic tunnel composite liner structure with a polyurea spray coating interlayer was proposed in this study. A theoretical model based on the state-space method was developed and verified using FEM models and existing theoretical models. Parametric analysis was conducted based on the theoretical model to investigate the influence of various variables, including interfacial shear stiffness, inner liner thickness, and outer liner elastic modulus.

It was concluded that the proposed theoretical model can be used successfully to calculate multilayer composite liner structures with high calculation efficiency. The overall deformation stiffness of the composite liner system increased with the interfacial shear stiffness. The sprayed coating interlayer significantly affects the residual force distribution between the outer and inner liners, which can also be affected by the adjustment of the thickness of the outer and inner liners. Thus, attention should be paid to these factors in the rational design of the proposed composite liner system.

With the development of China’s water conservancy projects, complex geological conditions, high surrounding rock stress, high internal and external water pressures, and other unique application scenarios have gradually increased. This places higher requirements on the bearing performance and impermeability of hydraulic tunnel lining structures. On the other hand, conventional hydraulic tunnel lining structures can hardly achieve a satisfactory balance between economy, structural safety, and impermeability. Thus, the proposed structure has the potential to be used in a wide range of applications.

With the introduction of graph structure learning into service classification, more accurate graph structures can significantly improve the precision of service classification. However, existing graph structure learning methods tend to rely on a single information source when attempting to eliminate noise in the original graph structure and lack consideration for the graph generation mechanism. To address this problem, this paper aims to propose a graph structure estimation neural network-based service classification (GSESC) model.

First, this method uses the local smoothing properties of graph convolutional networks (GCN) and combines them with the stochastic block model to serve as the graph generation mechanism. Next, it constructs a series of observation sets reflecting the intrinsic structure of the service from different perspectives to minimize biases introduced by a single information source. Subsequently, it integrates the observation model with the structural model to calculate the posterior distribution of the graph structure. Finally, it jointly optimizes GCN and the graph estimation process to obtain the optimal graph.

The authors conducted a series of experiments on the API data set and compared it with six baseline methods. The experimental results demonstrate the effectiveness of the GSESC model in service classification.

This paper argues that the data set used for service classification exhibits a strong community structure. In response to this, the paper innovatively applies a graph-based learning model that considers the underlying generation mechanism of the graph to the field of service classification and achieves good results.

Highlights the significance of organizational structure in some typical UK manufacturing firms. Features current research at the Sheffield Institute of Work Psychology, University of Sheffield. By determining structure, senior management is creating the backcloth against which decision making, communication and responsibilities are set. Sets out to reiterate the role of structure and examines some of the triggers for structural change. In striving for adaptive structures, senior management have to address certain dilemmas, not least the balance between “quick‐fix” solutions and longer term strategic planning. Whether a change in structure represents a fundamental change in attitudes on the part of all employees or an attempt by the MD to redefine control is discussed. Concludes that most UK manufacturing firms in the Centre for Economic Performance survey retain functional structures, but have undergone significant changes in terms of levels and roles.

This paper aims to present ball bearings with a composite structure based on the bionics principle and shows the comparison between five types of different structures.

By means of the finite element method, the stress and other parameters between different structures are compared and verified. Finally, the comprehensive parameters of different structures are evaluated by the analytic hierarchy process method.

The evaluation of the comprehensive parameters of five types of structures is shown here.

The value of this paper is calculated and compared to the parameters of five types of different structures, and the parameter score evaluation of each structure is given. Different structures can be selected according to different parameter requirements, which to provide a theoretical basis for the design of ball bearings.

The peer review history for this article is available at: https://publons.com/publon10.1108/ILT-10-2019-0413

The purpose of this paper is to compare the single-sided packaging structure and double-sided packaging structure of high-power module and study the overall heat dissipation performance and reliability of the module.

In this paper, the single-sided packaging structure and double-sided packaging structure of power module are designed based on Wolfspeed products. This paper is analyzed by finite element method. First, the heat dissipation performance of single-sided packaging structure and double-sided packaging structure is analyzed; second, the deformation and stress of single-sided packaging structure and double-sided packaging structure are compared and analyzed; and finally, the cumulative plastic deformation of single-sided packaging and double-sided packaging structures are compared and analyzed, and the fatigue life of the structure is calculated based on the plastic deformation.

In the heat transfer simulation, under the same power input, the heat dissipation performance of single-sided packaging structure is not as good as that of double-sided packaging structure. Under the reliability simulation of the same temperature cycle standard, the maximum equivalent stress of single-sided packaging structure is lower than that of double-sided packaging structure, but the fatigue life prediction based on plastic strain shows that the fatigue life of double-sided packaging structure is not different from that of single-sided packaging structure.

This paper creatively simulates the thermal characteristics and reliability of single-sided packaging structure and double-sided packaging structure and proves the advantages of double-sided packaging structure compared with single-sided packaging structure from the aspects of heat transfer performance and reliability.