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Article
Publication date: 19 April 2024

Mahesh Gaikwad, Suvir Singh, N. Gopalakrishnan, Pradeep Bhargava and Ajay Chourasia

This study investigates the impact of the fire decay phase on structural damage using the sectional analysis method. The primary objective of this work is to forecast the…

Abstract

Purpose

This study investigates the impact of the fire decay phase on structural damage using the sectional analysis method. The primary objective of this work is to forecast the non-dimensional capacity parameters for the axial and flexural load-carrying capacity of reinforced concrete (RC) sections for heating and the subsequent post-heating phase (decay phase) of the fire.

Design/methodology/approach

The sectional analysis method is used to determine the moment and axial capacities. The findings of sectional analysis and heat transfer for the heating stage are initially validated, and the analysis subsequently proceeds to determine the load capacity during the fire’s heating and decay phases by appropriately incorporating non-dimensional sectional and material parameters. The numerical analysis includes four fire curves with different cooling rates and steel percentages.

Findings

The study’s findings indicate that the rate at which the cooling process occurs after undergoing heating substantially impacts the axial and flexural capacity. The maximum degradation in axial and flexural capacity occurred in the range of 15–20% for cooling rates of 3 °C/min and 5 °C/min as compared to the capacity obtained at 120 min of heating for all steel percentages. As the fire cooling rate reduced to 1 °C/min, the highest deterioration in axial and flexural capacity reached 48–50% and 42–46%, respectively, in the post-heating stage.

Research limitations/implications

The established non-dimensional parameters for axial and flexural capacity are limited to the analysed section in the study owing to the thermal profile, however, this can be modified depending on the section geometry and fire scenario.

Practical implications

The study primarily focusses on the degradation of axial and flexural capacity at various time intervals during the entire fire exposure, including heating and cooling. The findings obtained showed that following the completion of the fire’s heating phase, the structural capacity continued to decrease over the subsequent post-heating period. It is recommended that structural members' fire resistance designs encompass both the heating and cooling phases of a fire. Since the capacity degradation varies with fire duration, the conventional method is inadequate to design the load capacity for appropriate fire safety. Therefore, it is essential to adopt a performance-based approach while designing structural elements' capacity for the desired fire resistance rating. The proposed technique of using non-dimensional parameters will effectively support predicting the load capacity for required fire resistance.

Originality/value

The fire-resistant requirements for reinforced concrete structures are generally established based on standard fire exposure conditions, which account for the fire growth phase. However, it is important to note that concrete structures can experience internal damage over time during the decay phase of fires, which can be quantitatively determined using the proposed non-dimensional parameter approach.

Details

Journal of Structural Fire Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 4 November 2022

Laiming Yu, Yaqin Fu and Yubing Dong

The purpose of this study is to investigate the thermomechanical condition on the shape memory property of Polybutylene adipate-co-terephthalate (PBAT). PBAT is a widely…

Abstract

Purpose

The purpose of this study is to investigate the thermomechanical condition on the shape memory property of Polybutylene adipate-co-terephthalate (PBAT). PBAT is a widely researched and rapidly developed biodegradable copolyester. In a tensile test, we found that the fractured PBAT samples had a heat-driven shape memory effect which piqued our interest, and it will lay a foundation for the application of PBAT in new fields (such as heat shrinkable film).

Design/methodology/approach

The shape memory effect of PBAT and the effect of the thermomechanical condition on its shape memory property were confirmed and systematically investigated by a thermal mechanical analyzer and tensile machine.

Findings

The results showed that the PBAT film had broad shape memory transform temperature and exhibited excellent thermomechanical stability and shape memory properties. The shape memory fixity ratio (Rf) of the PBAT films was increased with the prestrain temperature and prestrain, where the highest Rf exceeded 90%. The shape memory recovery ratio (Rr) of the PBAT films was increased with the shape memory recovery temperature and decreased with the prestrain value, and the highest Rr was almost 100%. Moreover, the PBAT films had high shape memory recovery stress which increased with the prestrain value and decreased with the prestrain temperature, and the highest shape memory recovery stress can reach 7.73 MPa.

Research limitations/implications

The results showed that PBAT had a broad shape memory transform temperature, exhibited excellent thermomechanical stability and shape memory performance, especially for the sample programmed at high temperature and had a larger prestrian, which will provide a reference for the design, processing and application of PBAT-based heat shrinkable film and smart materials.

Originality/value

This study confirmed and systematically investigated the shape memory effect of PBAT and the effect of the thermomechanical condition on the shape memory property of PBAT.

Details

Pigment & Resin Technology, vol. 53 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Book part
Publication date: 13 May 2024

Eelco van Eijck

Many in the private and public sectors see headhunting as a “necessary evil.” A tour of investors, business schools, executive and supervisory board directors throws up…

Abstract

Many in the private and public sectors see headhunting as a “necessary evil.” A tour of investors, business schools, executive and supervisory board directors throws up unflattering descriptions. Accusations of “opacity” are probably linked to the industry’s duty of discretion. Other observers signal a need for improvement: “pumping the same names around,” “emphasis on reputation, not merit,” “lack of quality” and “low innovation.” The battle to professionalize is underway. We look at the avenues ahead for executive hiring, the demise of the “old boys’ network” and the need for diversity and sustainability in modern organizations. We present the difficulties of running a headhunting firm, and distinguishing factors of the best players. We argue that selecting a headhunter demands the same rigor as choosing a lawyer, and six areas of improvement for executive search firms. Unpacking the Spartan marathon to the boardroom, we reveal the surprising estimates of the number of new high potentials entering the market annually. We conclude by looking at possible blind spots on both sides of the hiring equation that can undermine company interests, and continue to examine the march to professionalize the executive search industry.

An earlier form of this chapter by the author was published in Dutch in “Bestemming Boardroom: over zoeken en gevonden worden” (Boom, Amsterdam, 2018) and in English (online) by the Amrop Partnership (2021) as “Destination Boardroom 3: Mapping the Executive Search World.”

Open Access
Article
Publication date: 25 April 2024

Marianne Thejls Ziegler and Christoph Lütge

This study aims to analyse the differences between professional interaction mediated by video conferencing and direct professional interaction. The research identifies diverging…

Abstract

Purpose

This study aims to analyse the differences between professional interaction mediated by video conferencing and direct professional interaction. The research identifies diverging interests of office workers for the purpose of addressing work ethical and business ethical issues of professional collaboration, competition, and power in future hybrid work models.

Design/methodology/approach

Based on 28 qualitative interviews conducted between November 2020 and June 2021, and through the theoretical lens of phenomenology, the study develops explanatory hypotheses conceptualising four basic intentions of professional interaction and their corresponding preferences for video conferences and working on site.

Findings

The four intentions developed on the basis of the interviews are: the need for physical proximity; the challenge of collective creativity; the will to influence; and control of communication. This conceptual framework qualifies a moral ambivalence of professional interaction. The authors identify a connectivity paradox of professional interaction where the personal dimension remains unarticulated for the purpose of maintaining professionality. This tacit human connectivity is intertwined with latent power relations. This plasticity of both connectivity and power in direct interaction can be diminished by transferring the interaction to video conferencing.

Originality/value

The application of phenomenology to a collection of qualitative interviews has enabled the identification of underlying intention structures and the system in which they affect each other. This research identifies conflicts of interests between workers relative to their different self-perceived abilities to persevere in competitive professional interaction. It is therefore able to address consequences of future hybrid work models at an existential and societal level.

Article
Publication date: 24 April 2024

Shahriar Abubakri, Pritpal S. Mangat, Konstantinos Grigoriadis and Vincenzo Starinieri

Microwave curing (MC) can facilitate rapid concrete repair in cold climates without using conventional accelerated curing technologies which are environmentally unsustainable…

Abstract

Purpose

Microwave curing (MC) can facilitate rapid concrete repair in cold climates without using conventional accelerated curing technologies which are environmentally unsustainable. Accelerated curing of concrete under MC can contribute to the decarbonisation of the environment and provide economies in construction in several ways such as reducing construction time, energy efficiency, lower cement content, lower carbonation risk and reducing emissions from equipment.

Design/methodology/approach

The paper investigates moisture loss and pore properties of six cement-based proprietary concrete repair materials subjected to MC. The impact of MC on these properties is critically important for its successful implementation in practice and current literature lacks this information. Specimens were microwave cured for 40–45 min to surface temperatures between 39.9 and 44.1 °C. The fast-setting repair material was microwave cured for 15 min to 40.7 °C. MC causes a higher water loss which shows the importance of preventing drying during MC and the following 24 h.

Findings

Portland cement-based normal density repair mortars, including materials incorporating pfa and polymer latex, benefit from the thermal effect of MC on hydration, resulting in up to 24% reduction in porosity relative to normal curing. Low density and flowing repair materials suffer an increase in porosity up to 16% due to MC. The moisture loss at the end of MC and after 24h is related to the mix water content and porosity, respectively.

Originality/value

The research on the application of MC for rapid repair of concrete is original. The research was funded by the European commission following a very rigorous and competitive review process which ensured its originality. Original data on the parameters of porosity and moisture loss under MC are provided for different generic cementitious repair materials which have not been studied before. Application of MC to concrete construction especially in cold climates will provide environmental, economic and energy benefits.

Details

International Journal of Building Pathology and Adaptation, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2398-4708

Keywords

Article
Publication date: 23 April 2024

Margitta B. Beil-Hildebrand, Firuzan Kundt Sari, Patrick Kutschar and Lorri Birkholz

Nurse leaders are challenged by ethical issues in today’s complex health-care settings. The purpose of this study was to describe and analyze key elements of moral distress…

Abstract

Purpose

Nurse leaders are challenged by ethical issues in today’s complex health-care settings. The purpose of this study was to describe and analyze key elements of moral distress identified by nurse leaders from health-care systems in the USA, Germany, Austria and Switzerland. The aim was to develop an understanding of distressing ethical issues nurse leaders face in the USA and three German-speaking European countries.

Design/methodology/approach

This descriptive cross-sectional study surveyed a convenience sample of nurse leaders in the USA, Germany, Austria and Switzerland. The voluntary, anonymous survey also included qualitative questions and was distributed using the Qualtrics® platform. A thematic analysis of the qualitative data in each country was carried out and a comparative analysis identified similarities and differences between the groups of nurse leaders comparing the US data to that from three German-speaking European countries.

Findings

The survey was completed by 316 nurse leaders: Germany, Austria, and Switzerland (n = 225) and the USA (n = 91). Similar themes identified as causing all nurse leaders moral distress included a lack of individual and organizational integrity, hierarchical and interprofessional issues, lack of nursing professionalism, patient care/patient safety concerns, finances negatively impacting care and issues around social justice. Within these six themes, there were also differences between the USA and the three German-speaking European countries.

Originality/value

Understanding the experiences associated with distressing ethical situations can allow nurse leaders and organizations to focus on solutions and develop resilience to reduce moral distress in the USA and three German-speaking European countries.

Details

Leadership in Health Services, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1751-1879

Keywords

Open Access
Article
Publication date: 11 March 2024

Anna Hallberg, Ulrika Winblad and Mio Fredriksson

The build-up of large-scale COVID-19 testing required an unprecedented effort of coordination within decentralized healthcare systems around the world. The aim of the study was to…

Abstract

Purpose

The build-up of large-scale COVID-19 testing required an unprecedented effort of coordination within decentralized healthcare systems around the world. The aim of the study was to elucidate the challenges of vertical policy coordination between non-political actors at the national and regional levels regarding this policy issue, using Sweden as our case.

Design/methodology/approach

Interviews with key actors at the national and regional levels were analyzed using an adapted version of a conceptualization by Adam et al. (2019), depicting barriers to vertical policy coordination.

Findings

Our results show that the main issues in the Swedish context were related to parallel sovereignty and a vagueness regarding responsibilities and mandates as well as complex governmental structures and that this was exacerbated by the unfamiliarity and uncertainty of the policy issue. We conclude that understanding the interaction between the comprehensiveness and complexity of the policy issue and the institutional context is crucial to achieving effective vertical policy coordination.

Originality/value

Many studies have focused on countries’ overall pandemic responses, but in order to improve the outcome of future pandemics, it is also important to learn from more specific response measures.

Details

Journal of Health Organization and Management, vol. 38 no. 9
Type: Research Article
ISSN: 1477-7266

Keywords

Abstract

Details

Black Expression and White Generosity
Type: Book
ISBN: 978-1-80382-758-2

Open Access
Article
Publication date: 25 December 2023

Anna Trubetskaya, Alan Ryan, Daryl John Powell and Connor Moore

Output from the Irish Dairy Industry has grown rapidly since the abolition of quotas in 2015, with processors investing heavily in capacity expansion to deal with the extra milk…

Abstract

Purpose

Output from the Irish Dairy Industry has grown rapidly since the abolition of quotas in 2015, with processors investing heavily in capacity expansion to deal with the extra milk volumes. Further capacity gains may be achieved by extending the processing season into the winter, a key enabler for which being the reduction of duration of the winter maintenance overhaul period. This paper aims to investigate if Lean Six Sigma tools and techniques can be used to enhance operational maintenance performance, thereby releasing additional processing capacity.

Design/methodology/approach

Combining the Six-Sigma Define, Measure, Analyse, Improve, Control (DMAIC) methodology and the structured approach of Turnaround Maintenance (TAM) widely used in process industries creates a novel hybrid model that promises substantial improvement in maintenance overhaul execution. This paper presents a case study applying the DMAIC/TAM model to Ireland’s largest dairy processing site to optimise the annual maintenance shutdown. The objective was to deliver a 30% reduction in the duration of the overhaul, enabling an extension of the processing season.

Findings

Application of the DMAIC/TAM hybrid resulted in process enhancements, employee engagement and a clear roadmap for the operations team. Project goals were delivered, and original objectives exceeded, resulting in €8.9m additional value to the business and a reduction of 36% in the duration of the overhaul.

Practical implications

The results demonstrate that the model provides a structure that promotes systematic working and a continuous improvement focus that can have substantial benefits for wider industry. Opportunities for further model refinement were identified and will enhance performance in subsequent overhauls.

Originality/value

To the best of the authors’ knowledge, this is the first time that the structure and tools of DMAIC and TAM have been combined into a hybrid methodology and applied in an Irish industrial setting.

Details

International Journal of Lean Six Sigma, vol. 15 no. 8
Type: Research Article
ISSN: 2040-4166

Keywords

Article
Publication date: 18 October 2022

Reza Amini and Pooneh Kardar

This paper aims to achieve phosphating via optimal features of Mg metal as a suitable base coating, which is considered for other properties such as barrier properties against the…

Abstract

Purpose

This paper aims to achieve phosphating via optimal features of Mg metal as a suitable base coating, which is considered for other properties such as barrier properties against the passage of several factors.

Design/methodology/approach

In this research, in the phosphate bath, immersion time, temperature and the content of sodium nitrite as an accelerator were changed.

Findings

As a result, increasing the immersion time of AZ31 Mg alloy samples in the phosphating bath as well as increasing the ratio of sodium dodecyl sulfate (SDS) concentration to sodium nitrite concentration in the phosphating bath formulation increase the mass of phosphating formed per unit area of the Mg alloy. The results of the scanning electron microscope test showed phosphating is not completely formed in short immersion times, which is a thin and uneven layer.

Research limitations/implications

Mg and its alloys are sensitive to galvanic corrosion, which would lead to generating several holes in the metal. As such, it causes a decrease in mechanical stability as well as an unfavorable appearance.

Practical implications

Mg is used in several industries such as automobile and computer parts, mobile phones, astronaut compounds, sports goods and home appliances.

Social implications

Nevertheless, Mg has high chemical reactivity, so an oxide-hydroxide layer is formed on its surface, which has a harmful effect on the adhesion and uniformity of the coating applied on Mg.

Originality/value

By increasing the ratio of SDS concentration to sodium nitrite concentration in the phosphating bath, the corrosion resistance of the phosphating increases.

Details

Pigment & Resin Technology, vol. 53 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

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