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Book part
Publication date: 8 August 2022

Joel Smethurst and William Powrie

Earthworks are the embankments and cuttings that allow a railway to maintain a certain line, level and grade through the landscape. Earth embankments consist of an engineered bank

Abstract

Earthworks are the embankments and cuttings that allow a railway to maintain a certain line, level and grade through the landscape. Earth embankments consist of an engineered bank of earth that carries the railway above the natural ground. A cutting is used to carry the railway through ground with a natural level above the line of the railway. Modern (post 1960s) earthworks are carefully engineered to perform well. However, many railways run on earthworks that were constructed over 100 years ago without the use of mechanised plant. The quality of construction of older earthworks was often poor compared with present-day engineering practice. Ageing of the earthwork structures, and the greater demands of heavier and faster trains and climatic change, means that earthworks suffer ultimate and serviceability failures that can present operational difficulties. Older earthworks that fail or do not perform well require maintenance and repair, and sometimes complete replacement. This chapter explores the main engineering considerations for modern earthworks, and the challenges associated with older earthworks including their modes of failure and upgrade and repair.

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Sustainable Railway Engineering and Operations
Type: Book
ISBN: 978-1-83909-589-4

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Article
Publication date: 1 June 2020

Ziqiang Fang, Songlin Peng, Jiangang Yi and Jun Du

The purpose of this paper is to optimize the structure of plough blades in a ploughshare mixer using the discrete element method (DEM) simulations.

232

Abstract

Purpose

The purpose of this paper is to optimize the structure of plough blades in a ploughshare mixer using the discrete element method (DEM) simulations.

Design/methodology/approach

Using the validated DEM model, three numerical tests are conducted to determine how the mixing performance evolves as structural parameters of blades change. Results from the analysis provide basis for structure optimization of blades. The structural parameters include sweep angle of blade γ, regular axial pitch p and regular circumferential angular offset α. The parameters to evaluate mixing performance include mass flow rate and Lacey index.

Findings

The DEM results show that the mixing performance at γ of 35° is better than 15°, 25° and 45°. The mixer which has a p of less than or equal to 1.11 · b is more efficient than the mixer which has a p greater than 1.11 · b, where b is tail width of blade. The circumferential symmetric distribution of blades (α = 180°) is more beneficial to improve the mixing performance in comparison with the circumferential asymmetric distribution (α < 180°). Based on the results, an optimized mixer with a γ of 35°, a p of 0.61 · b and an α of 180° is proposed, which has a better mixing performance compared to all mixers listed.

Originality/value

The structural parameters of blades, including γ, p and α, are found to be critical for good mixing. From the view angle of structure optimization of plough blades, a new ploughshare mixer with a γ of 35°, a p of 0.61 · b and an α of 180° is investigated and recommended for improving mixing efficiency.

Details

Engineering Computations, vol. 37 no. 9
Type: Research Article
ISSN: 0264-4401

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Book part
Publication date: 30 July 1993

MICHAEL A. KEMP and CHRISTOPHER MAXWELL

Abstract

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Contingent Valuation: A Critical Assessment
Type: Book
ISBN: 978-1-84950-860-5

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Article
Publication date: 11 September 2007

Ad den Otter and Stephen Emmitt

Effective teams use a balance of synchronous and asynchronous communication. Team communication is dependent on the communication acts of team members and the ability of managers…

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Abstract

Purpose

Effective teams use a balance of synchronous and asynchronous communication. Team communication is dependent on the communication acts of team members and the ability of managers to facilitate, stimulate and motivate them. Team members from organizations using different information systems tend to have different understanding, opinions, and rates of adoption and skills levels regarding specific IT tools. The purpose of this paper is to explore the effective use of tools for communication in design teams and the strategies for the use of specific tools.

Design/methodology/approach

A review of the potential effectiveness of synchronous and asynchronous communication means and tools for team communication leads to a review of research conducted into the use of two relatively new electronic tools for team communication by design teams in The Netherlands.

Findings

The research results revealed that a collective framework for team communication and collaboration using electronic tools was missing. There was also evidence of a lack of understanding by the users of the proper use of the tools, a lack of training, poor management competences to stimulate proper use. There was also evidence that the rivalry of tools tended to hinder, rather than improve, effectiveness of team communication.

Research limitations/implications

The findings are limited to the cases investigated; however, they tend to support earlier findings into construction team communication. There is a need for a better collective understanding of team communication, which should be supported with training to develop appropriate skills, both for the use of new technologies and for the use of team rules.

Originality/value

The results provide information and advice for design and project managers concerned with improving communications in design and construction projects.

Details

Engineering, Construction and Architectural Management, vol. 14 no. 5
Type: Research Article
ISSN: 0969-9988

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Article
Publication date: 1 March 1994

F. Rahali, S. Ansermet, J. Ardalan and D. Otter

Silicon sensors are semiconductor devices which transform a physical effect (such as pressure, acceleration, flux) into electrical effects (resistance, capacitance variation)…

52

Abstract

Silicon sensors are semiconductor devices which transform a physical effect (such as pressure, acceleration, flux) into electrical effects (resistance, capacitance variation). Fabrication of these silicon sensors requires very precise control of the silicon micromachining. Some silicon foundries have adapted their experience in integrated circuit manufacturing to silicon sensor production and thus have reduced the costs and dimensions of the silicon sensors. Standard thick film technology has brought versatility to silicon sensor technology. Silicon sensors mounted on a ceramic substrate give fast development, high performance and low cost to OEMs. An alternative solution is the integrated silicon sensor including sensor and circuitry on the same silicon chip. This has been developed for specific applications.

Details

Microelectronics International, vol. 11 no. 3
Type: Research Article
ISSN: 1356-5362

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Book part
Publication date: 23 October 2017

Mariangela Bonasia and Rosaria Rita Canale

The aim of this chapter is to show the limits of the European policy model and to support the existence, through straightforward empirical analysis, of an inverse relationship…

Abstract

The aim of this chapter is to show the limits of the European policy model and to support the existence, through straightforward empirical analysis, of an inverse relationship both in the short run and in the long run between trust in institutions and unemployment. The empirical methodology relies on dynamic panel data techniques allowing measuring in a single equation both the long-run relationship and the short-run speed of adjustment among variables. This connection appears to be valid both in the Eurozone considered as a whole and in particular in peripheral countries, where the macroeconomic dynamics have been, under this respect, much more divergent from the average. This outcome allows proofing that to consolidate the European process of integration in the long run, institutions should have as main objective not only inflation but especially unemployment.

Details

Economic Imbalances and Institutional Changes to the Euro and the European Union
Type: Book
ISBN: 978-1-78714-510-8

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Available. Open Access. Open Access
Book part
Publication date: 3 December 2024

Iryna Kushnir and Nuve Yazgan

Given that this book places the interconnectedness of international sustainable development and education particularly in times of crises at the centre of attention, it is…

Abstract

Given that this book places the interconnectedness of international sustainable development and education particularly in times of crises at the centre of attention, it is impossible to disregard the nuanced nature of this crisis context. Based on a review of relevant literature, this chapter focuses on the following four main areas. First, it analyses the complex nature of the definition of the crisis, as multiple attempts to understand the phenomenon of crises and their various classifications have been consensual in recognising that crises are multidimensional and interrelated, that they are integral to the process of change and that they present a range of interconnected factors that distort the normal operation of people, organisations, their relationships, resources, etc. Second, this chapter explains the phenomenon of glocalisation in relation to crises to further detail how intertwined different crises are. When applied to the analysis of crises, the phenomenon of glocalisation is paramount in understanding how locally born crises can trigger globally reaching effects and vice versa. Third, this chapter discusses the impact of crises on international sustainable development. Finally, it is proposed in this chapter that education should be viewed as an important tool in tackling crises and, thus, easing the progress towards sustainable development internationally. This chapter provides important contextualisation regarding the evolving multidimensional and intertwined crises against the background of which the discussion in this book embarks on in its subsequent parts.

Details

Education and Sustainable Development in the Context of Crises: International Case Studies of Transformational Change
Type: Book
ISBN: 978-1-83797-773-4

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Article
Publication date: 30 August 2011

Mohammed N. Juaim and Mohammad A. Hassanain

The objective of this paper is to present an assessment of the factors that influence the process of developing and implementing the architectural program (design brief) for…

967

Abstract

Purpose

The objective of this paper is to present an assessment of the factors that influence the process of developing and implementing the architectural program (design brief) for buildings projects.

Design/methodology/approach

Published literature has been analyzed and interviews with a group of design professionals and owner's representatives were conducted for the purpose of identifying the factors that influence the process of developing and implementing the architectural program for building projects. This resulted in the identification of 28 factors, which were classified into several groups. A questionnaire was developed that included the identified factors to assess their level of importance. Responses to the survey were received from 50 Architectural/Engineering (A/E) design firms and three major owners of building projects. These 53 respondents were distributed throughout the Eastern Province, Riyadh and Jeddah in Saudi Arabia.

Findings

The research has confirmed the importance of all the identified factors, and identified the most influential factors in each of the factor groups. The survey findings indicate that the respondents recognize the significance of the factors that relate to the architectural programmer, the role of communication throughout the programming process, the program data, the management and control of the architectural programming process, the allocated time and budget, and the owner and their representatives, in descending order, respectively when endeavoring on the development and implementation of the architectural program for building projects.

Originality/value

This paper provides a practical value to architectural programmers, design professionals, facility managers, and building owners endeavoring on planning, designing, constructing, and operating new building projects.

Details

Structural Survey, vol. 29 no. 4
Type: Research Article
ISSN: 0263-080X

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Article
Publication date: 11 July 2024

Francisco Sánchez-Moreno, David MacManus, Fernando Tejero, Josep Hueso-Rebassa and Christopher Sheaf

The decrease in specific thrust achieved by Ultra-High Bypass Ratio (UHBPR) aero-engines allows for a reduction in specific fuel consumption. However, the typical associated…

89

Abstract

Purpose

The decrease in specific thrust achieved by Ultra-High Bypass Ratio (UHBPR) aero-engines allows for a reduction in specific fuel consumption. However, the typical associated larger fan size might increase the nacelle drag, weight and the detrimental interference effects with the airframe. Consequently, the benefits from the new UHBPR aero-engine cycle may be eroded. This paper aims to evaluate the potential improvement in the aerodynamic performance of compact nacelles for installed aero-engine configuration.

Design/methodology/approach

Drooped and scarfed non-axisymmetric compact and conventional nacelle designs were down selected from a multi-point CFD-based optimisation. These were computationally assessed at a set of installation positions on a contemporary wide-body, twin-engine transonic aircraft. Both cruise and off-design conditions were evaluated. A thrust and drag accounting method was applied to evaluate different aircraft, powerplant and nacelle performance metrics.

Findings

The aircraft with the compact nacelle configuration installed at a typical installation position provided a reduction in aircraft cruise fuel consumption of 0.44% relative to the conventional architecture. However, at the same installation position, the compact design exhibits a large flow separation at windmilling conditions that is translated into an overall aircraft drag penalty of approximately 5.6% of the standard cruise net thrust. Additionally, the interference effects of a compact nacelle are more sensitive to deviations in mass flow capture ratio (MFCR) from the nominal windmilling diversion condition.

Originality/value

This work provides a comprehensive analysis of not only the performance but also the aerodynamics at an aircraft level of compact nacelles compared to conventional configurations for a range of installations positions at cruise. Additionally, the engine-airframe integration aerodynamics is assessed at an off-design windmilling condition which constitutes a key novelty of this paper.

Details

Aircraft Engineering and Aerospace Technology, vol. 96 no. 6
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 27 July 2020

Kim Schildkamp, Iwan Wopereis, Marian Kat-De Jong, Annette Peet and IJsbrand Hoetjes

Innovative use of information and communications technology (ICT) requires (new) knowledge and skills for the group that has the biggest impact on the quality of education…

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Abstract

Purpose

Innovative use of information and communications technology (ICT) requires (new) knowledge and skills for the group that has the biggest impact on the quality of education: instructors. Facilitating professional development (PD) of instructors is crucial for the quality of one’s education system(s), perhaps even more so in times of a pandemic.

Design/methodology/approach

Based on the authors’ analysis of reviews published in the last decade, this paper summarizes the key building blocks of effective PD on the innovative use of ICT during a pandemic. The authors used these building blocks to reflect on two national PD initiatives developed to support institutions of higher education in instructional use of ICT while dealing with the consequences of the COVID-19 pandemic.

Findings

Both PD initiatives include the same building blocks: (1) content-related building blocks focused on technological knowledge, (2) active learning and expert-supported PD (didactics-related building blocks) and (3) contextual building blocks consisting of clearly defined goals focused on the instructor's own practice, use of technology, sustained duration (e.g. taking place over a longer period of time) and evidence-informed PD. One contextual building block that was not evident in the reviews but emerged as a vital building block is “responsiveness” to the situation and needs of the participants.

Originality/value

High-quality PD is crucial if one wants to safeguard the quality of (online) instruction and learning to ensure high-quality education for all students. This paper can contribute to enhancing the quality of much-needed PD on online teaching (during, but also after COVID-19).

Details

Journal of Professional Capital and Community, vol. 5 no. 3/4
Type: Research Article
ISSN: 2056-9548

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