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Gas insulated systems, such as gas insulated lines (GIL), use insulating gas, mostly sulfur hexalfluoride (SF₆), to enable a higher dielectric strength compared to e.g. air. However, under high voltage direct current conditions, charge accumulation and electric field stress may occur, which may lead to partial discharge or system failure. Therefore, numerical simulations are used to design the system and determine the electric field and charge distribution. Although the gas conduction shows a more complex current–voltage characteristic compared to solid insulation, the electric conductivity of the SF₆ gas is set as constant in most works. The purpose of this study is to investigate different approaches to address the conduction in the gas properly for numerical simulations.

In this work, two approaches are investigated to address the conduction in the insulating gas and are compared to each other. One method is an ion-drift-diffusion model, where the conduction in the gas is described by the ion motion in the SF₆ gas. However, this method is computationally expensive. Alternatively, a less complex approach is an electro-thermal model with the application of an electric conductivity model for the SF₆ gas. Measurements show that the electric conductivity in the SF₆ gas has a nonlinear dependency on temperature, electric field and gas pressure. From these measurements, an electric conductivity model was developed. Both methods are compared by simulation results, where different parameters and conditions are considered, to investigate the potential of the electric conductivity model as a computationally less expensive alternative.

The simulation results of both simulation approaches show similar results, proving the electric conductivity for the SF₆ gas as a valid alternative. Using the electro-thermal model approach with the application of the electric conductivity model enables a solution time up to six times faster compared to the ion-drift-diffusion model. The application of the model allows to examine the influence of different parameters such as temperature and gas pressure on the electric field distribution in the GIL, whereas the ion-drift-diffusion model enables to investigate the distribution of homo- and heteropolar charges in the insulation gas.

This work presents numerical simulation models for high voltage direct current GIL, where the conduction in the SF₆ gas is described more precisely compared to a definition of a constant electric conductivity value for the insulation gas. The electric conductivity model for the SF₆ gas allows for consideration of the current–voltage characteristics of the gas, is computationally less expensive compared to an ion-drift diffusion model and needs considerably less solution time.

In response to rising energy prices and growing environmental concerns, there is a growing demand for environmentally friendly building facilities. This study investigates optimizing energy consumption and improves the level of accuracy when selecting suitable materials and components with minimal impact on the overall energy consumption of buildings.

This study was carried out from the perspective of an educational building's energy simulation, using a validated building energy analysis tool Green Building Studio (GBS). There were eight parameters analyzed considering at least two connected variables without measuring the initial building configuration. After that, Autodesk Revit and Insight 360 were used to make similar scenarios of the best performance selections so that the general results could be compared and the initial hypothesis could be proven.

In this study, the initial building analysis showed that there was an annual energy use of 139 kBtu/sf and the estimated carbon emissions were about 156 tons/yr. After the parametric analysis, the maximum energy saving was about 32.38%, considering the best performance scenario with a reduction of CO₂ emissions of around 28.85%.

The outcome of this study will help Bangladeshi architect/designers to make appropriate decisions regarding the selection of suitable building materials and components at the initial stage of any project in terms of the energy consumption aspects. In addition, energy-efficient buildings provide cleaner combustion and better circulation than traditional buildings, that is why they reduce indoor air pollution, maintaining a safe, healthy and sustainable environment for future generations.

In the context of the digital age, this study aims to investigate the impact of citizens' digital participation on the scientific and democratic decision-making processes of the government. Specifically, the authors focus on the factors influencing citizens' digital participation, with a particular emphasis on their digital skills.

Exploring the influence of citizens' digital skills on their digital participation is of great practical significance for eliminating the digital divide and for promoting a life characterized by enriched digital interactions with the public. This study selected the social consciousness survey database of Chinese netizens in 2017, used ordered Probit and OLS models, and comprehensively used the instrumental variable method (IV), causal stepwise regression method and bootstrap method to empirically verify and construct a mechanism model of the influence of digital skills on citizens' digital participation.

The empirical findings indicate a noteworthy positive association between citizens' proficiency in digital skills and their active engagement in digital activities. This relationship is positively mediated by factors such as political interest and attention to social issues, underscoring their role in encouraging greater digital participation. Conversely, national identity exhibits a counteractive influence on this mechanism, potentially discouraging digital engagement. Notably, the impact of digital skill mastery on digital participation is more pronounced among non-elderly individuals and those residing in metropolitan areas, highlighting the significance of demographic characteristics in this context.

These research results can help the government and other organizations make better decisions and facilitate improvement of citizens' digital participation by promoting their mastery of digital skills.

Intumescent coatings are nowadays a dominant passive system used to protect structural materials in case of fire. Due to their reactive swelling behaviour, intumescent coatings are particularly complex materials to be modelled and predicted, which can be extremely useful especially for performance-based fire safety designs. In addition, many parameters influence their performance, and this challenges the definition and quantification of their material properties. Several approaches and models of various complexities are proposed in the literature, and they are reviewed and analysed in a critical literature review.

Analytical, finite-difference and finite-element methods for modelling intumescent coatings are compared, followed by the definition and quantification of the main physical, thermal, and optical properties of intumescent coatings: swelled thickness, thermal conductivity and resistance, density, specific heat capacity, and emissivity/absorptivity.

The study highlights the scarce consideration of key influencing factors on the material properties, and the tendency to simplify the problem into effective thermo-physical properties, such as effective thermal conductivity. As a conclusion, the literature review underlines the lack of homogenisation of modelling approaches and material properties, as well as the need for a universal modelling method that can generally simulate the performance of intumescent coatings, combine the large amount of published experimental data, and reliably produce fire-safe performance-based designs.

Due to their limited applicability, high complexity and little comparability, the presented literature review does not focus on analysing and comparing different multi-component models, constituted of many model-specific input parameters. On the contrary, the presented literature review compares various approaches, models and thermo-physical properties which primarily focusses on solving the heat transfer problem through swelling intumescent systems.

The presented literature review analyses and discusses the various modelling approaches to describe and predict the behaviour of swelling intumescent coatings as fire protection for structural materials. Due to the vast variety of available commercial products and potential testing conditions, these data are rarely compared and combined to achieve an overall understanding on the response of intumescent coatings as fire protection measure. The study highlights the lack of information and homogenisation of various modelling approaches, and it underlines the research needs about several aspects related to the intumescent coating behaviour modelling, also providing some useful suggestions for future studies.

This article aims to clarify the impact of stock market liberalization on corporate green technology innovation, analyze its mechanism from the perspectives of financing constraints and environmental management level and explore heterogeneity.

Using the panel data of Chinese enterprises from 2010 to 2020, this article adopts the multi-point difference-in-difference (DID) method to test the impact of stock market liberalization on enterprise green technology innovation and its conduction pathway.

The outcomes demonstrate that stock market liberalization contributes to the furthering of green technology innovation. The heterogeneity test reveals that this promotion is more pronounced for private companies, small-scale companies and companies with high information transparency. The mediating effect test shows that stock market liberalization boosts green technology innovation by alleviating corporate financing constraints and improving corporate environmental management.

This article elucidates the impact path of stock market liberalization on corporate green innovation based on alleviating corporate financing constraints and improving corporate environmental management levels. From the perspective of corporate green technology innovation, this article provides evidence from emerging market countries for the economic effects of capital market opening, which helps to further improve the level of green innovation.

Understanding the thermal performance of sandcrete hollow block walls in the tropic is very essential for occupants' well-being, productivity and efficiency, due to its widespread application in buildings in the study area. Lokoja, in Nigeria, lies in the warm humid zone with its attendant's high temperatures all year round. Thus, providing an acceptable walling material that will control the high indoor air temperature becomes imperative. This paper assessed sandcrete hollow blocks as a walling material used in Lokoja, to determine the thermal performances for effective thermal comfort of the residents.

It involves the construction of a habitable model building with the commonly available sandcrete hollow blocks in the area. One unit of Cryopak iMINI Temperature and Relative Humidity Data Logger called new generation intelligent iMINI with Serial Number and Product Code MX-CI-145–0009 and MX-HE-S-16-L was installed, to record the indoor air temperature and relative humidity data at an interval of one hour, for 12 months covering dry and wet seasons. The results of the recorded data were downloaded to an excel spread sheet for assessment and analysis throughout the seasons. The values were computed using the temperature–humidity index (THI) equation, with a view to determine the indoor thermal comfort level category.

The study revealed that sandcrete hollow block walls provide thermal discomfort of the indoor environment for both seasons, with attendant adverse effects in the comfort of the occupants. The paper concludes that proper orientation of buildings, planting of trees, use of low absorbing or reflective surface materials, application of cavity walls to receive insulation materials in between the hollow spaces provided, instead of the single walling as well as providing shading device elements, can improve users' comfort and also ameliorate the heat effect on the external surface of building transferred into the interior by conduction, radiation or convection within the area and in the tropics at large. Other thermally eco-friendly wall materials available in Lokoja includes timber, stabilized laterite–cement blocks, burnt bricks and earth-mud bricks which can be used to replace sandcrete hollow block walls. These alternative wall materials are used for construction of residential and office buildings by the colonial government of Sir Fredrick Lugard in the study area.

The application of sandcrete hollow blocks as a wall material is in vogue, not minding its thermal discomfort to the users and the environment; this is due to its availability and ease of production. The acceptability of this walling material requires holistic study to unravel the best way to reduce the thermal discomfort inherent in its application.

The author succeeded in revealing the thermal performance of sandcrete hollow blocks as walling material in Lokoja, the study area. It is a first attempt at understanding the performance for human comfort in the area. This will greatly assist the resident and other researchers to improve on the application of sandcrete hollow blocks as walling material towards ensuring that maximum indoor thermal comfort is achieved.

This paper aims to study the influence of cylindrical texture parameters on the lubrication performance of static and dynamic pressure thrust bearings (hereinafter referred to as thrust bearings) and to optimize their lubrication performance using multiobjective optimization.

The influence of texture parameters on the lubrication performance of thrust bearings was studied based on the modified Reynolds equation. The objective functions are predicted through the BP neural network, and the texture parameters were optimized using the improved multiobjective ant lion algorithm (MOALA).

Compared with smooth surface, the introduction of texture can improve the lubrication properties. Under the optimization of the improved algorithm, when the texture diameter, depth, spacing and number are approximately 0.2 mm, 0.5 mm, 5 mm and 34, respectively, the loading capacity is increased by around 27.7% and the temperature is reduced by around 1.55°C.

This paper studies the effect of texture parameters on the lubrication properties of thrust bearings based on the modified Reynolds equation and performs multiobjective optimization through an improved MOALA.

Neurostrategy is an abductive decision-making process developed from the knowledge generated within the network of decision-makers. It links cognitive style with the team's decisional adaptability in relation to the organization's purpose. Neurostrategy differs from traditional methods, in which it addresses negative utility or decisional trauma, highlighting the variety of interests that are the main cause of team misalignment and allowing for the development of strategies to address them. Neurostrategy enables the classification of strategy deficiencies based on cohesion, coordination, communication and conduction (Co4).

This paper introduces a novel approach called relational neurostrategy (RNS) to elucidate the knowledge processes influencing decision-making. RNS aims to “capture” the intricate processes guiding decisions, enabling the network's decisional plasticity in both forms and contents. This adaptability is crucial for effectively addressing posed challenges, while simultaneously mitigating the impact of diverse interests. The methodology also ensures transparency in the decision-making process and generates an effective solution strategy.

The RNS addresses two critical aspects of the decision-making process. Firstly, it reduces unnecessary variety stemming from multiple interpretations and secondly, it minimizes the adverse impact of diverse interests within the decision-making network. This approach results in strong and credible decisions that reflect the collective intelligence, cooperation and collaborative efforts of the network, rather than being imposed as absolute truths.

The RNS stands out as a distinctive decision-making method, setting itself apart from existing approaches. Its uniqueness becomes evident in its ability to address the question “what prevents the authors from … ?” from this inquiry, RNS successfully integrates unrequired variety and negative utility. By doing so, it strategically narrows down the search field to the universe of distinctions that truly constitute the problem. This innovative process not only enhances efficiency but also fosters a high level of participation in the strategic design of potential solutions. In essence, RNS brings unprecedented value by effectively navigating the intricacies of decision-making and maximizing the relevance of the identified problem space.

This paper numerically investigates the effect of cavity radiation on the thermal response of hollow aluminium tubes and facade systems subjected to fire.

Finite element simulations were performed using ABAQUS 6.14. The accuracy of the numerical model was established through experimental and numerical results available in the literature. The proposed numerical model was utilised to study the effect of cavity radiation on the thermal response of aluminium hollow tubes and facade system. Different scenarios were considered to assess the applicability of the commonly used lumped capacitance heat transfer model.

The effects of cavity radiation were found to be significant for non-uniform fire exposure conditions. The maximum temperature of a hollow aluminium tube with 1-sided fire exposure was found to be 86% greater when cavity radiation was considered. Further, the time to attain critical temperature under non-uniform fire exposure, as calculated from the conventional lumped heat capacity heat transfer model, was non-conservative when compared to that predicted by the proposed simulation approach considering cavity radiation. A metal temperature of 550 °C was attained about 18 min earlier than what was calculated by the lumped heat capacitance model.

The present study will serve as a basis for the study of the effects of cavity radiation on the thermo-mechanical response of aluminium hollow tubes and facade systems. Such thermo-mechanical analyses will enable the study of the effects of cavity radiation on the failure mechanisms of facade systems.

Cavity radiation was found to significantly affect the thermal response of hollow aluminium tubes and façade systems. In design processes, it is essential to consider the potential consequences of non-uniform heating situations, as they can have a significant impact on the temperature of structures. It was also shown that the use of lumped heat capacity heat transfer model in cases of non-uniform fire exposure is unsuitable for the thermal analysis of such systems.

This is the first detailed investigation of the effects of cavity radiation on the thermal response of aluminium tubes and façade systems for different fire exposure conditions.

Diesel has traditionally been considered the best-suited and most widely used fuel in various sectors, including manufacturing industries, power production, automobiles and transportation. However, with the ongoing crisis of fossil fuel inadequacy, the search for alternative fuels and their application in these sectors has become increasingly important. One particularly interesting and beneficial alternative fuel is biodiesel derived from bio sources.

In this research, an attempt was made to use biodiesel in an unconventional micro gas turbine engine. It will remove the concentric use of diesel engines for power production by improving fuel efficiency as well as increasing the power production rate. Before the fuel is used enormously, it has to be checked in many ways such as performance, emission and combustion analysis experimentally.

In this paper, a detailed experimental study was made for the use of Spirulina microalgae biodiesel in a micro gas turbine. A small-scale setup with the primary micro gas turbine and secondary instruments such as a data acquisition system and AVL gas analyser. The reason for selecting the third-generation microalgae is due to its high lipid and biodiesel production rate. For the conduction of experimental tests, certain conditions were followed in addition that the engine rotating rpm was varied from 4,000, 5,000 and 6,000 rpm. The favourable and predicted results were obtained with the use of microalgae biodiesel.

The performance and combustion results were not exactly equal or greater for biodiesel blends but close to the values of pure diesel; however, the reduction in the emission of CO was at the appreciable level for the used spirulina microalgae biodiesel. The emission of nitrogen oxides and carbon dioxide was a little higher than the use of pure diesel. This experimental analysis results proved that the use of spirulina microalgae biodiesel is both economical and effective replacement for fossil fuel.