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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.

Abnormal vibrations often occur in the liquid oxygen kerosene transmission pipelines of rocket engines, which seriously threaten their safety. Improper handling can result in failed rocket launches and significant economic losses. Therefore, this paper aims to examine vibrations in transmission pipelines.

In this study, a three-dimensional high-pressure pipeline model composed of corrugated pipes, multi-section bent pipes, and other auxiliary structures was established. The fluid–solid coupling method was used to analyse vibration characteristics of the pipeline under various external excitations. The simulation results were visualised using MATLAB, and their validity was verified via a thermal test.

In this study, the vibration mechanism of a complex high-pressure pipeline was examined via a visualisation method. The results showed that the low-frequency vibration of the pipe was caused by fluid self-excited pressure pulsation, whereas the vibration of the engine system caused a high-frequency vibration of the pipeline. The excitation of external pressure pulses did not significantly affect the vibrations of the pipelines. The visualisation results indicated that the severe vibration position of the pipeline thermal test is mainly concentrated between the inlet and outlet and between the two bellows.

The results of this study aid in understanding the causes of abnormal vibrations in rocket engine pipelines.

The causes of different vibration frequencies in the complex pipelines of rocket engines and the propagation characteristics of external vibration excitation were obtained.

Gas transmission pipelines are at constant risk of gas leakage or fire due to various atmospheric environments, corrosion on pipe metal surfaces and other external factors. This study aims to reduce the human and financial risks associated with gas transmission by regularly monitoring pipeline performance, controlling situations and preventing disasters.

Facility managers can monitor the status of gas transmission lines in real-time by integrating sensor information into a building information modeling (BIM) 3D model. Using the Monitoring Panel plugin, coded in C# programming language and operated through Navisworks software, the model provides up-to-date information on pipeline safety and performance.

By collecting project information on the BIM and installing critical sensors, this approach allows facility manager to observe the real-time safety status of gas pipelines. If any risks of gas leakage or accidents are identified by the sensors, the BIM model quickly shows the location of the incident, enabling facility managers to make the best decisions to reduce financial and life risks. This intelligent gas transmission pipeline approach changes traditional risk management and inspection methods, minimizing the risk of explosion and gas leakage in the environment.

This research distinguishes itself from related work by integrating sensor data into a BIM model for real-time monitoring and providing facility managers with up-to-date safety information. By leveraging intelligent gas transmission pipelines, the system enables quick identification and location of potential hazards, reducing financial and human risks associated with gas transmission.

The aim of this study is to assess the opportunity for the development of hydrocarbon transportation using high-strength steel (HSS) in pipeline construction in terms of cost savings and reliability.

Several optimizations of pipeline design and operations were performed to estimate the total life-cycle cost variation associated with different grades of high-strength steel. The generalized reduced gradient (GRG) method was used in an Excel table to determine optimal total life cycle each pipeline. Variables used in this optimization with respect to each steel grade were as follows: pipeline external diameter, wall thickness, number of compression stations and installed power in each compression station. The reliability of a pipeline with optimal cost was assessed to highlight the impact of steel grade on pipeline reliability.

The study showed that the cost reduction is strongly dependent on the adopted gas pipeline configuration. The number of compression stations and external diameter are the main factors influencing the pipeline total life cycle cost, while the steel price seems to have a minor effect, the reduction of the gas pipeline total life cycle does not exceed 5% even with a 50% difference in pipe steel prices between X70 and X100 steels. On the other side, for the same external diameter, X100 steel presents better pipeline reliability against carbonic corrosion compared to X70 steel.

The main contribution of this study is to provide a decision-support tool to help pipeline constructors enhance the profitability of natural gas transmission pipelines. The optimization method used is simple to use for design engineers during a feasibility study.

The present study presents one step to fill the gap concerning the question of balancing the trade-off between cost savings and structural reliability in high-strength steel pipelines during the early stages of feasibility studies. The optimal design and operations parameters ensuring cost savings on total life cycle costs are identified via an optimization method. The impact of selected optimal parameters on the long-term pipeline service life was estimated via a structural reliability analysis.

The skillsets of science, technology, engineering and mathematics (STEM) graduates are widely recognised to be important for economic prosperity. At the same time, it is broadly accepted that in England there is a need to increase the number of people studying STEM degree courses and working in STEM. However, despite decades of interventions post-16, STEM participation rates remain lower than projected requirements. Some research reports suggest a lack of positive attitudes towards these subjects and aspirations amongst some social groups. As these debates continue, official reports such as those released by the Department for Education show these patterns from the labour market and higher education (HE) extend to both attainment and participation in science and math in school.

In this paper, the authors summarise the authors' findings from the analysis of official reports, policy documents and major research reports focussing on attainment in school science and math and post-compulsory STEM participation.

The authors identify the problematic ways in which STEM subject choices are made across the student life cycle and then discuss how the leaky pipeline metaphor can be ambiguous and needs to be used with caution.

Some aspects identified here warrant further research and will be of particular interest to researchers, practitioners and policymakers.

In this new report, the authors identify the problematic ways in which STEM subject choices are made across the student life cycle in England and then discuss how the leaky pipeline metaphor can be ambiguous and needs to be used with caution.

The purpose of this paper is to understand demographic group (race, first-generation college graduate, gender, age) differences among perceived family and faculty social and family financial support within the US graduate school admissions pipeline in the social sciences.

Using data from a cross-sectional convenience sample survey (N = 99), this paper looks at ordinal social support variables (faculty member support, family social support and family financial support) by demographic groups. This paper uses a Mann–Whitney U test to compare first-generation status, race and gender and a Kruskal–Wallis H test to compare age groups.

This paper finds that applicants over 27 years old had significantly less faculty support in the graduate admissions pipeline compared to other age groups; differences in faculty support across race were marginally significant (p = 0.057). Regarding family social support, this paper finds first-generation applicants, male applicants and applicants over 27 years old report lower levels of support. Finally, this paper finds first-generation applicants and applicants over 27 years old report lower levels of familial financial support.

Previous literature on graduate admissions – published in this journal (Pieper and Krsmanovic, 2022) and others – does not consider experiences up to and before applicants hit the “submit” button on graduate applicants, which the authors term the graduate admissions pipeline. Instead, most previous literatures focus on faculty committees and validity of required application materials. Thus, this study begins to answer Posselt and Grodsky’s (2017) call to develop an understanding of applicant experiences and support within the graduate admissions pipeline.

To elaborate the picture of credibility assessment by examining how participants of online discussion evaluate the informational credibility of conspiracy theories.

Descriptive quantitative analysis and qualitative content analysis of 2,663 posts submitted to seven Reddit threads discussing a conspiracy operation, that is, the damage of the Nord Stream gas pipelines in September 2022. It was examined how the participants of online discussion assess the credibility of information constitutive of conspiracy theories speculating about (1) suspected actors responsible for the damage, (2) their motives and (3) the ways in which the damage was made. The credibility assessments focussed on diverse sources offering information about the above three factors.

The participants assessed the credibility of information by drawing on four main criteria: plausibility of arguments, honesty in argumentation, similarity to one's beliefs and provision of evidence. Most assessments were negative and indicated doubt about the informational believability of conspiracy theories about the damage. Of the information sources referred to in the discussion, the posts submitted by fellow participants, television programmes and statements provided by governmental organizations were judged most critically, due to implausible argumentation and advocacy of biased views.

As the study focuses on a sample of posts dealing with conspiracy theories about a particular event, the findings cannot be generalized to concern the informational credibility conspiracy narratives.

The study pioneers by providing an in-depth analysis of the nature of credibility assessments by focussing on information constitutive of conspiracy theories.

Pipelines are subject to pits, holes and cracks after staying in service for a while, especially in harsh environments. To repair the pipelines, composite materials are used, due to composite materials' low cost, high-corrosion resistance and easy handling. This study aims to investigate the reliability of the blister test for evaluating the bonding strength of multiwall carbon nanotube (MWCNT) on woven carbon-reinforced epoxy.

Flexural, hardness and Izod impact tests were used to evaluate MWCNT effect on the epoxy by adding different amounts, 0.2, 0.4, 0.6, 0.8 and 1 wt. %, of MWCNT, to be compared with pure epoxy.

The results showed that 0.8 wt.% gives the highest strength. The experimental results of 0.8 wt.% MWCNT reinforced carbon composite was compared with the finite element model under blister test, and the results showed high similarities.

Evaluation of the reliability and the advantages of MWCNT considering the high aspect ratio and high tensile strength, which is more than 15 times compared to steel, MWCNT enhances the strength, stiffness and toughness of epoxy used as a matrix in repairing pipelines, which leads to an increase in the resistance of composite materials against oil internal pressure before delamination.

All gender identity is socialized, but anything gendered feminine is marginalized. In the United States, we live in a patriarchal culture that is bounded by binary gender identity. Up to this point, work on gender and education leadership has remained within the bounds of patriarchy, and thus been confined to binary, hierarchical gender definitions. This study pushes past prior work to advance a more complex and messy understanding of how identity impacts aspiring leaders in their careers. Using Carol Gilligan and Snider (2018) Listening Guide Method, this study of 18 aspiring school leaders of different gender identities, sexual identities, and races focuses on how gender identity and gender performance impact school leaders' career trajectories. A key finding of this study is that women, regardless of race or sexual identity, have difficulty finding mentors while men, regardless of race or sexual identity, are tapped by schools leaders and offered mentoring opportunities. This chapter posits a new framework for mentoring that will lead to more liberatory pipeline structures.