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1 – 10 of 337
Article
Publication date: 10 January 2020

Chensen Ding

This paper aims to provide designers/engineers, in engineering structural design and analysis, approaches to freely and accurately modify structures (geometric and/or material)…

Abstract

Purpose

This paper aims to provide designers/engineers, in engineering structural design and analysis, approaches to freely and accurately modify structures (geometric and/or material), and then quickly provide real-time capability to obtain the numerical solutions of the modified structures (designs).

Design/methodology/approach

The authors propose an isogeometric independent coefficients (IGA-IC) method for a fast reanalysis of structures with geometric and material modifications. Firstly, the authors seamlessly integrate computer-aided design (CAD) and computer-aided engineering (CAE) by capitalizing upon isogeometric analysis (IGA). Hence, the authors can easily modify the structural geometry only by changing the control point positions without tedious transformations between CAE and CAD models; and modify material characters simply based on knots vectors. Besides, more accurate solutions can be obtained because of the high order degree of the spline functions that are used as interpolation functions. Secondly, the authors advance the proposed independent coefficients method within IGA for fast numerical simulation of the modified designs, thereby significantly reducing the enormous time spent in repeatedly numerical evaluations.

Findings

This proposed scheme is efficient and accurate for modifying the structural geometry by simply changing the control point positions, and material characters by knots vectors. The enormous time spent in repeated full numerical simulations for reanalysis is significantly reduced. Hence, enabling quickly modifying structural geometry and material, and analyzing the modified model for practicality in design stages.

Originality/value

The authors herein advance and propose the IGA-IC scheme. Where, it provides designers to fasten and simple designs and modify structures (both geometric and material). It then can quickly in real-time obtain numerical solutions of the modified structures. It is a powerful tool in practical engineering design and analysis process for local modification. While this method is an approximation method designed for local modifications, it generally cannot provide an exact numerical solution and its effectiveness for large modification deserves further study.

Open Access
Article
Publication date: 29 July 2019

Ren Yang, Qi Song and Pu Chen

The purpose of this paper is to establish and implement a direct topological reanalysis algorithm for general successive structural modifications, based on the updating matrix…

Abstract

Purpose

The purpose of this paper is to establish and implement a direct topological reanalysis algorithm for general successive structural modifications, based on the updating matrix triangular factorization (UMTF) method for non-topological modification proposed by Song et al. [Computers and Structures, 143(2014):60-72].

Design/methodology/approach

In this method, topological modifications are viewed as a union of symbolic and numerical change of structural matrices. The numerical part is dealt with UMTF by directly updating the matrix triangular factors. For symbolic change, an integral structure which consists of all potential nodes/elements is introduced to avoid side effects on the efficiency during successive modifications. Necessary pre- and post processing are also developed for memory-economic matrix manipulation.

Findings

The new reanalysis algorithm is applicable to successive general structural modifications for arbitrary modification amplitudes and locations. It explicitly updates the factor matrices of the modified structure and thus guarantees the accuracy as full direct analysis while greatly enhancing the efficiency.

Practical implications

Examples including evolutionary structural optimization and sequential construction analysis show the capability and efficiency of the algorithm.

Originality/value

This innovative paper makes direct topological reanalysis be applicable for successive structural modifications in many different areas.

Details

Engineering Computations, vol. 36 no. 8
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 24 February 2012

Amir Hossein Alavi, Ali Mollahasani, Amir Hossein Gandomi and Jafar Boluori Bazaz

The purpose of this paper is to develop new constitutive models to predict the soil deformation moduli using multi expression programming (MEP). The soil deformation parameters…

Abstract

Purpose

The purpose of this paper is to develop new constitutive models to predict the soil deformation moduli using multi expression programming (MEP). The soil deformation parameters formulated are secant (Es) and reloading (Er) moduli.

Design/methodology/approach

MEP is a new branch of classical genetic programming. The models obtained using this method are developed upon a series of plate load tests conducted on different soil types. The best models are selected after developing and controlling several models with different combinations of the influencing parameters. The validation of the models is verified using several statistical criteria. For more verification, sensitivity and parametric analyses are carried out.

Findings

The results indicate that the proposed models give precise estimations of the soil deformation moduli. The Es prediction model provides considerably better results than the model developed for Er. The Es formulation outperforms several empirical models found in the literature. The validation phases confirm the efficiency of the models for their general application to the soil moduli estimation. In general, the derived models are suitable for fine‐grained soils.

Originality/value

These equations may be used by designers to check the general validity of the laboratory and field test results or to control the solutions developed by more in‐depth deterministic analyses.

Article
Publication date: 17 May 2011

Carsten Segerlund Frederiksen, Jorgen Segerlund Frederiksen, Janice Maria Sisson and Stacey Lee Osbrough

Major shifts in the southern hemisphere circulation occurred during the mid‐1970s concurrent with large reductions in southern Australian winter rainfall associated with decreased…

Abstract

Purpose

Major shifts in the southern hemisphere circulation occurred during the mid‐1970s concurrent with large reductions in southern Australian winter rainfall associated with decreased cyclogenesis. The purpose of this paper is to study changes in cyclogenesis over southern Australia during the last 50 years, examine the ability of coupled climate models to simulate the winter circulation changes, and discuss projected changes in winter circulation and rainfall under different climate change scenarios.

Design/methodology/approach

Three dimensional instability theory is used to study changes in cyclogenesis. The response of 22 coupled model intercomparison project three (CMIP3) IPCC climate models to observed increases in greenhouse gases, from pre‐industrial to the end of the twentieth century, is examined. The authors focus on two diagnostics closely related to the changes in cyclogenesis: changes in the 300 hPa zonal wind strength; and changes in the baroclinic instability. Projected changes in baroclinic instability and rainfall are investigated in SRESB1, SRESA1B and SRESA2 scenarios.

Findings

There has been a 30 per cent reduction in the growth rate of the leading storm track mode crossing southern Australia in the 1975‐1994 period, and a 37 per cent reduction in the 1997‐2006 period, when compared to 1949‐1968. Most of the CMIP3 models capture the changes in the zonal wind; only about a third the changes in baroclinic instability. Projected changes in baroclinic instability and rainfall suggest further reductions in the growth rate of storm track modes and further large reductions in rainfall over southern Australia.

Originality/value

The paper addresses a major cause of the reduction in Australian winter rainfall, and provides guidance on future‐projected changes.

Details

International Journal of Climate Change Strategies and Management, vol. 3 no. 2
Type: Research Article
ISSN: 1756-8692

Keywords

Article
Publication date: 1 August 1995

Rik Pieters, Kitty Koelemeijer and Henk Roest

When assimilation processes occur, expectations have a directimpact on experiences, and experiences bias the memory for priorexpectations. Reports the results of two studies which…

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Abstract

When assimilation processes occur, expectations have a direct impact on experiences, and experiences bias the memory for prior expectations. Reports the results of two studies which examine assimilation processes using path analysis. Formulates implications and recommendations for service management and for research.

Details

International Journal of Service Industry Management, vol. 6 no. 3
Type: Research Article
ISSN: 0956-4233

Keywords

Article
Publication date: 1 August 1996

Manolis Papadrakakis, Yiannis Tsompanakis, Ernest Hinton and Johann Sienz

Investigates the efficiency of hybrid solution methods when incorporated into large‐scale topology and shape optimization problems and to demonstrate their influence on the…

Abstract

Investigates the efficiency of hybrid solution methods when incorporated into large‐scale topology and shape optimization problems and to demonstrate their influence on the overall performance of the optimization algorithms. Implements three innovative solution methods based on the preconditioned conjugate gradient (PCG) and Lanczos algorithms. The first method is a PCG algorithm with a preconditioner resulted from a complete or an incomplete Cholesky factorization, the second is a PCG algorithm in which a truncated Neumann series expansion is used as preconditioner, and the third is a preconditioned Lanczos algorithm properly modified to treat multiple right‐hand sides. The numerical tests presented demonstrate the computational advantages of the proposed methods which become more pronounced in large‐scale and/or computationally intensive optimization problems.

Details

Engineering Computations, vol. 13 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

Book part
Publication date: 13 May 2017

Otávio Bartalotti, Gray Calhoun and Yang He

This chapter develops a novel bootstrap procedure to obtain robust bias-corrected confidence intervals in regression discontinuity (RD) designs. The procedure uses a wild…

Abstract

This chapter develops a novel bootstrap procedure to obtain robust bias-corrected confidence intervals in regression discontinuity (RD) designs. The procedure uses a wild bootstrap from a second-order local polynomial to estimate the bias of the local linear RD estimator; the bias is then subtracted from the original estimator. The bias-corrected estimator is then bootstrapped itself to generate valid confidence intervals (CIs). The CIs generated by this procedure are valid under conditions similar to Calonico, Cattaneo, and Titiunik’s (2014) analytical correction – that is, when the bias of the naive RD estimator would otherwise prevent valid inference. This chapter also provides simulation evidence that our method is as accurate as the analytical corrections and we demonstrate its use through a reanalysis of Ludwig and Miller’s (2007) Head Start dataset.

Details

Regression Discontinuity Designs
Type: Book
ISBN: 978-1-78714-390-6

Keywords

Article
Publication date: 19 September 2016

Elaine Pamela Harris, Deryl Northcott, Moataz Moamen Elmassri and Jari Huikku

In the field of strategic investment decision making (SIDM) a body of research has grown up via international case studies and organisation-based fieldwork. However, there has…

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Abstract

Purpose

In the field of strategic investment decision making (SIDM) a body of research has grown up via international case studies and organisation-based fieldwork. However, there has been little systematic theorisation around SIDM processes and practices. The purpose of this paper is to show how strong structuration theory (SST) can be employed to guide how future SIDM studies are conducted and theorised.

Design/methodology/approach

The authors draw upon the concepts from SST to reanalyse prior empirically based work. The authors apply SST-informed analysis to four SIDM case studies selected from the total of 18 published over the period 1970-2016 to explore the utility of SST compared with other approaches.

Findings

The analysis highlights the role of agents’ knowledgeability and position-practice relations in SIDM, which has largely been neglected by prior studies. The authors demonstrate the potential of SST to inform meso-level theorising by applying it to four published case studies. Whilst the authors argue for the adoption of SST, the authors also identify key methodological and conceptual issues in using SST in SIDM research.

Research limitations/implications

The examples and recommendations could assist management accounting researchers, particularly those engaged in case studies and organisational fieldwork, to build knowledge via the improved comparison, integration and theorisation of cases undertaken by different researchers in different contexts.

Originality/value

The authors offer a bridge between SST concepts and case study evidence for theorising, carrying out and analysing case study and field research on SIDM.

Details

Accounting, Auditing & Accountability Journal, vol. 29 no. 7
Type: Research Article
ISSN: 0951-3574

Keywords

Article
Publication date: 1 January 2009

Hugh M. Pattinson and Arch G. Woodside

This case study research report aims to include collecting additional field interviews with the original and additional executives participating in the original case study (on the…

2410

Abstract

Purpose

This case study research report aims to include collecting additional field interviews with the original and additional executives participating in the original case study (on the Zaplet software applications firm) to enhance the interpretations by the original case study investigators as well as add‐in downstream events occurring after the original report. The focus of the study is to increase descriptive knowledge and understanding of innovation and diffusion processes in developing high‐tech disruptive software technologies.

Design/methodology/approach

The study includes an application of the long‐interview method and reinterpretation of original case data along with preparing and interpreting decision system analysis and chronological maps.

Findings

The reinterpretation and expansion of the original case study illustrate dramatic revisions in plans and implementing new applications following positive and negative responses by third‐parties and lead‐user customers to alpha and beta designs. Concrete field trials occur frequently in shaping where and how the firm goes about changing its direction. Third‐parties play critical roles in multiple time periods in shaping the firm's new product development direction.

Research limitations/implications

The case study reanalysis and expansion are generalizable to innovation and diffusion theory and not to a specific population of firms.

Practical implications

The paper illustrates the wisdom of Tom Peter's dictum, “Put it to tin quickly” and Dwight Eisenhower's focus on improvising, “The plan is nothing, planning is everything.”

Originality/value

Formal sensemaking of what happened helps to destroy the myth that executives must have the resources before innovating. Resources follow vision and action (implementing) is the hidden and great lesson of this paper – what Tom Peters means when he writes about the value in creating a “skunk works” – using “borrowed” time, material, places, and creative juices to make things happen.

Details

Journal of Business & Industrial Marketing, vol. 24 no. 1
Type: Research Article
ISSN: 0885-8624

Keywords

Article
Publication date: 1 June 2006

David Collins and Ceri Watkins

The purpose of this paper is to offer a critical review of the work of Tom Peters.

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Abstract

Purpose

The purpose of this paper is to offer a critical review of the work of Tom Peters.

Design/methodology/approach

Notes a degree of narrative experimentation in the works of Tom Peters. Offers a narrative typology to describe this narrative change, suggests a number of reasons for this narrative experimentation and outlines topics for future research in this area.

Findings

The paper suggests that Peters' narrative experimentation reflects twin frustrations. Namely Peters' frustration with the short‐term orientations and innate conservatism of the US business élite and peripheralization in Corporate America.

Originality/value

The paper proposes an original narrative typology for the examination of Peters' work and suggests directions for future research.

Details

Management Decision, vol. 44 no. 5
Type: Research Article
ISSN: 0025-1747

Keywords

1 – 10 of 337