M. Nosratollahi, M. Mortazavi, A. Adami and M. Hosseini
The purpose of this paper is the optimal design of a reentry vehicle configuration to minimize the mission cost which is equal to minimize the heat absorbed (thermal protection…
Abstract
Purpose
The purpose of this paper is the optimal design of a reentry vehicle configuration to minimize the mission cost which is equal to minimize the heat absorbed (thermal protection system mass) and structural mass and to maximize the drag coefficient (trajectory errors and minimum final velocity).
Design/methodology/approach
There are two optimization approaches for solving this problem: multiobjective optimization (lead to Pareto optimal solutions); and single‐objective optimization (lead to one optimal solution). Single‐objective genetic algorithms (GA) and multiobjective Genetic Algorithms (MOGA) are employed for optimization. In second approach, if there are n objectives (n+1) GA run is needed to find nearest point (optimum point), which leads to increase the time processing. Thus, a modified GA called single run GA (SRGA) is presented as third approach to avoid increasing design time. It means if there are n objectives, just one GA run is enough.
Findings
Two multi module function – Ackley and bump function – are selected for examination the third approach. Results of MOGA, GA and SRGA are presented which show SRGA approach can find the nearest point in much shorter time with acceptable accuracy.
Originality/value
GA, MOGA and SRGA approaches are applied to multidisciplinary design optimization of a reentry vehicle configuration and results show the efficiency of SRGA in complex design optimization problem.
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Indermeet Sawhney, John Morgan and Afsaneh Tajer
The National Health Service Plan (DoH, 2000) requires that patients receive copies of correspondence between health professionals about them, as of right. Patients with learning…
Abstract
The National Health Service Plan (DoH, 2000) requires that patients receive copies of correspondence between health professionals about them, as of right. Patients with learning disabilities are not exempt from this rule. Copying letters to patients with learning disabilities is undoubtedly going to be challenging and complex for professionals working with them and, because of the heterogeneous nature of this group, specific guidelines need to be in place to support professionals in this task. The aim of the study was to ascertain the views of various professionals working in learning disability teams, on the copying of clinical letters to patients and their carers. The majority of respondents commented that, if letters are copied to patients with learning disabilities, then the persons may find it difficult to understand them, and a separate ‘simpler’ letter may need to be sent. Despite expressing concerns about this policy, the majority stated that they will be sending copies of letters regularly in their clinical practice in the future.
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Hasan Fevzi Cugen, Semra Arslan Selcuk and Yusuf Arayici
Building Information Modelling in building processes brings significant efficiency gains. However, its use in restoration projects is still experimental. On the other hand, more…
Abstract
Purpose
Building Information Modelling in building processes brings significant efficiency gains. However, its use in restoration projects is still experimental. On the other hand, more than traditional methods are needed for communication, collaboration, and shared understanding. Hence, the main research question is how to enhance these aspects in multinational projects with information transparency challenges and the need for shared understanding among stakeholders. This research aims to develop and propose a hybrid modelling approach that integrates traditional and BIM-based information process workflows through testing and evaluating to what extent BIM can be used in restoration projects without excessive efforts.
Design/methodology/approach
Considering this aim, the case study, the Mahmud Pasha Hammam as the heritage building, a 15th-century structure located in Serbia, was studied with the action research strategy to enable action-based learning by doing. Alongside the 2D documentation as the traditional method for the existing structure, restoration design proposals were also produced for the new additions to the heritage structure with BIM.
Findings
A new BIM use scenario was experimented with and proposed, proving BIM implementation's potential impact on heritage restoration projects. A hybrid model was developed that meets the requirements of existing regulations and specifications, where restoration proposals were visualized quickly, quantity take-off was produced, and technical drawings were generated instantly.
Originality/value
This hybrid modelling workflow integrates HBIM with traditional methods in restoration projects to improve communication, efficiency, and collaboration in a real-time professional project.
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Brea L. Perry and Allen J. LeBlanc
Purpose: The goal of Volume 21 of Advances in Medical Sociology, entitled Sexual and Gender Minority Health, is to showcase recent developments and areas for future research…
Abstract
Purpose: The goal of Volume 21 of Advances in Medical Sociology, entitled Sexual and Gender Minority Health, is to showcase recent developments and areas for future research related to the health, well-being, and healthcare experiences of LGBTQA+ (Lesbian, Gay, Transgender, Queer, Asexual, and related communities that do not identify as heterosexual) persons and communities.
Approach: In this introduction to the volume, we trace the historical development of research on sexual and gender minority (SGM) health, discussing how priorities, theories, and evidence have evolved over time. We conclude with brief suggestions for future research and an overview of the articles presented in this volume.
Findings: Research on SGM health has flourished in the past two decades. This trend has occurred in conjunction with a period of intense social, political, and legal discourse about the civil rights of SGM persons, which has increased understanding and recognition of SGM experiences. However, recent advances have often been met with resistance and backlash rooted in enduring social stigma and long histories of discrimination and prejudice that reinforce and maintain health disparities faced by SGM populations.
Value: Our review highlights the need for additional research to understand minority stress processes, risk factors, and resiliency, particularly for those at the intersection of SGM and racial/ethnic or socioeconomic marginality.
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These days, managers have to be constantly aware of means of potential growth if they want to stay in the game. Competition from similar products, changing technology and…
Abstract
These days, managers have to be constantly aware of means of potential growth if they want to stay in the game. Competition from similar products, changing technology and increasing costs all play their part in putting pressure on firms to keep rethinking and expanding. Mergers are more and more frequent and many businesses have expanded to become global organizations. But if growth is sometimes the only option it is also very often a risky one. Expansion demands investment of time, money and people and has to be carefully managed to bring the desired returns. Though there is a way to increase the odds of success: simple and effective communication in all directions.
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Reviews the latest management developments across the globe and pinpoints practical implications from cutting‐edge research and case studies.
Abstract
Purpose
Reviews the latest management developments across the globe and pinpoints practical implications from cutting‐edge research and case studies.
Design/methodology/approach
This briefing is prepared by an independent writer who adds their own impartial comments and places the articles in context.
Findings
John F. Kennedy once claimed that “leadership and learning are indispensable to each other”. In a world that seemingly refuses to stand still, the sentiments of the former US President have never been more apt. Because as change invariably brings new challenges, organizations lacking the knowledge to respond may soon find themselves left behind. So how can companies prosper amid the complexity and uncertainty that characterize the twenty‐first century business world? A key factor may be the definition of the organization itself.
Practical implications
Provides strategic insights and practical thinking that have influenced some of the world's leading organizations.
Originality/value
The briefing saves busy executives and researchers hours of reading time by selecting only the very best, most pertinent information and presenting it in a condensed and easy‐to‐digest format.
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Amirhossein Adami, Mahda Mortazavi and Mehran Nosratollahi
For complex engineering problems, multidisciplinary design optimization (MDO) techniques use some disciplines that need to be run several times in different modules. In addition…
Abstract
Purpose
For complex engineering problems, multidisciplinary design optimization (MDO) techniques use some disciplines that need to be run several times in different modules. In addition, mathematical modeling of a discipline can be improved for each module. The purpose of this paper is to show that multi-modular design optimization (MMO) improves the design performances in comparison with MDO technique for complex systems.
Design/methodology/approach
MDO framework and MMO framework are developed to optimum design of a complex system. The nonlinear equality and inequality constrains are considered. The system optimizers included Genetic Algorithm and Sequential Quadratic Programming.
Findings
As shown, fewer design variables (optimization variables) are needed at the system level for MMO. Unshared variables are optimized in the related module when shared variables are optimized at the system level. The results of this research show that MMO has lower elapsed times (14 percent) with lower F-count (16 percent).
Practical implications
The monopropellant propulsion upper-stage is selected as a case study. In this paper, the efficient model of the monopropellant propulsion system is proposed. According to the results, the proposed model has acceptable accuracy in mass model (error < 2 percent), performance estimation (error < 6 percent) and geometry estimation (error < 10 percent).
Originality/value
The monopropellant propulsion system is broken down into the three important modules including propellant tank (tank and propellant), pressurized feeding (tank and gas) and thruster (catalyst, nozzle and catalysts bed) when chemical decomposition, aerothermodynamics, mass and configuration, catalyst and structure have been considered as the disciplines. The both MMO and MDO frameworks are developed for the monopropellant propulsion system.
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Karoline Schnaider, Limin Gu and Oscar Rantatalo
The purpose of this study is to examine the use of digital technologies by teachers and students in teaching and learning from a multimodal layer perspective.
Abstract
Purpose
The purpose of this study is to examine the use of digital technologies by teachers and students in teaching and learning from a multimodal layer perspective.
Design/methodology/approach
The article reviews 64 studies on technology use. A content analysis based on the theoretical concepts of “multimodal layers” was used to synthesise previous research.
Findings
The findings indicate that the use of technology in classroom practices by teachers and students is multifaceted and that transitions exist between technologies and sign-systems and are differently related to sign-making activities and thus constitute different uses. Between layers, traces can be made that connect the use of technology to differences in sign-making activities.
Practical implications
A multimodal layer perspective on technology use is fruitful to understand what happens at the intersection of technology and human activities in school practices. Moreover, more attention to multimodal layers can inform future effective technology usage and design.
Originality/value
The review offers comprehensive insights on how previous research has studied technology using multimodal layers as an analytical lens.
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Oluwaseyi Alabi Awodele, Douglas Omoregie Aghimien, Olutayo Gabriel Akinkunmi and Clinton Ohis Aigbavboa
Due to its cost savings nature and ability to ensure constant jobs for contractors, this study aims to assess the capability of the labour-only procurement system to serve as a…
Abstract
Purpose
Due to its cost savings nature and ability to ensure constant jobs for contractors, this study aims to assess the capability of the labour-only procurement system to serve as a surviving strategy for construction contractors in a challenging economy.
Design/methodology/approach
The study adopted a mixed-methods design. An interview and questionnaire were used to harness information from 98 construction participants who have been involved in labour-only procured projects. These respondents were identified through snowballing. Frequency, percentage, mean item score, Mann–Whitney u-test and content analysis were used in analysing the data gathered.
Findings
Result revealed that participants are willing to execute more projects through this system because it gives considerable cost savings for clients and provides reduction in contractor’s risk and allows them to maintain healthy cash flow. The main factors influencing its usage are the client’s decision to procure materials, need for job at hand for contractors and the need for referrals from clients for subsequent jobs.
Practical implications
Findings of this study will assist contractors to understand the potential of this procurement system as a surviving option in a harsh economy. Small and medium contractors can make use of this available opportunity of having projects at hand at reduced risk to ensure continuous cash flow to keep their organisations afloat.
Originality/value
The contribution of this study to the body of knowledge lies in its provision of a reasonable insight on the inherent nature of a procurement system as a surviving strategy for contractors unlike the usual assessment of the generic survival strategies adopted in other studies.
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Douglas Omoregie Aghimien, Emmanuel Imuetiyan Aghimien, Akinlolu Oyebobola Fadiyimu and Taiwo Fadeke Adegbembo
The economic downturn in Nigeria calls for the need to appraise the survival strategies being adopted by organisations within the built environment, as it plays a major role in…
Abstract
Purpose
The economic downturn in Nigeria calls for the need to appraise the survival strategies being adopted by organisations within the built environment, as it plays a major role in the development of every nation. The purpose of this paper is, therefore, to appraise the survival strategies of organisations within the built environment, with a view to showcasing these strategies to ensure continuous survival of organisations within the industry.
Design/methodology/approach
The study adopted a survey approach, and construction professionals across the six geo-political zones of the country were sampled using structured questionnaire. Data gathered were analysed using percentage, Kruskal–Wallis H-test and factor analysis.
Findings
The study revealed that organisation- and workforce management-related strategies are the most adopted survival strategies in the country, as they have the highest factor loading and accounts for about 37 per cent of the total extracted factors. This is followed by the adoption of strategies relating to organisation’s innovation, diversification, financial management and organisation’s networking, the combination of which accounts for 27.5 per cent of all extracted factors.
Research limitations/implications
Findings of this study imply that although organisations within the built environment see the need for effective management of their organisation and workforce in a bid to survive in the harsh economic situation of the country, more need to be done as regards the other identified survival strategies, as they can help ensure the survival of these organisations.
Originality/value
This study contributes to the body of knowledge as it showcases the survival strategies being adopted by the different organisations within the built environment in the challenging Nigerian economy, as against the usual common practice of studying specific organisations within the industry.