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Article
Publication date: 7 June 2019

Peng Geng and Jianhua Liu

The more precise decision map is important to generate better-fused image. Guided filter can preserve edge information effectively. The purpose of his study is to use guided filter

Abstract

Purpose

The more precise decision map is important to generate better-fused image. Guided filter can preserve edge information effectively. The purpose of his study is to use guided filter to form the precise decision map and highly informatively fused image.

Design/methodology/approach

The dual tree complex wavelet transform is adopted to decompose the source images into high frequency and low frequency coefficients. Sum of modified Laplacian method is introduced as the focus metric in dual tree complex wavelet coefficients. The guided filter is guided by the dual tree complex wavelet coefficient when the sum of modified Laplacian is used as the input image. The output image of guided filter is used to produce the decision map to fuse dual tree complex wavelet coefficient of source images.

Findings

The sum of modified Laplacian of dual tree complex wavelet coefficient can be used as the guided image in guided filter to generate better decision map. Comparison with the other state-of-the-art methods illustrates that the proposed approach is more effective in fusing the multifocus images both visual performance and objective evaluation.

Originality/value

The sum of modified Laplacian of dual tree complex wavelet coefficient is introduced to be used as the guided image in guided filter to generate better decision map. This method is fast and effect to fuse the source images. Comparison with the other state-of-the-art methods illustrates that the proposed approach is more effective in fusing the multifocus images both visual performance and objective evaluation.

Details

Industrial Robot: the international journal of robotics research and application, vol. 46 no. 3
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 12 April 2018

Ambuj Sharma, Sandeep Kumar and Amit Tyagi

The real challenges in online crack detection testing based on guided waves are random noise as well as narrow-band coherent noise; and to achieve efficient structural health…

Abstract

Purpose

The real challenges in online crack detection testing based on guided waves are random noise as well as narrow-band coherent noise; and to achieve efficient structural health assessment methodology, magnificent extraction of noise and analysis of the signals are essential. The purpose of this paper is to provide optimal noise filtering technique for Lamb waves in the diagnosis of structural singularities.

Design/methodology/approach

Filtration of time-frequency information of guided elastic waves through the noisy signal is investigated in the present analysis using matched filtering technique which “sniffs” the signal buried in noise and most favorable mother wavelet based denoising methods. The optimal wavelet function is selected using Shannon’s entropy criterion and verified by the analysis of root mean square error of the filtered signal.

Findings

Wavelet matched filter method, a newly developed filtering technique in this work and which is a combination of the wavelet transform and matched filtering method, significantly improves the accuracy of the filtered signal and identifies relatively small damage, especially in enormously noisy data. A comparative study is also performed using the statistical tool to know acceptability and practicability of filtered signals for guided wave application.

Practical implications

The proposed filtering techniques can be utilized in online monitoring of civil and mechanical structures. The algorithm of the method is easy to implement and found to be successful in accurately detecting damage.

Originality/value

Although many techniques have been developed over the past several years to suppress random noise in Lamb wave signal but filtration of interferences of wave modes and boundary reflection is not in a much matured stage and thus needs further investigation. The present study contains detailed information about various noise filtering methods, newly developed filtration technique and their efficacy in handling the above mentioned issues.

Details

Multidiscipline Modeling in Materials and Structures, vol. 14 no. 4
Type: Research Article
ISSN: 1573-6105

Keywords

Abstract

Details

Leadership, Communication, and Social Influence
Type: Book
ISBN: 978-1-83867-118-1

Article
Publication date: 1 April 1992

Peter Suber

It is possible that the universe of available information will become so large that some teachers might actually control their students' command of it the way the mapmaker…

Abstract

It is possible that the universe of available information will become so large that some teachers might actually control their students' command of it the way the mapmaker controls the explorer in the wilderness. We must resist this temptation: our interest should not be to limit the alternatives that students see, but to make sure that they are able to make responsible judgments. We must educate students for intellectual autonomy, not discipleship, so they can navigate for themselves in the wilderness of information. We must present our considered views, of course, but for an audience that more and more will judge them in light of their alternatives. Enhanced access to information will make us comic figures if we present our own views as if our critics were silent. Educating students for autonomy is not as easy as typing keywords at a terminal and catching a cascade of citations in a basket; it requires real teaching.

Details

Library Hi Tech, vol. 10 no. 4
Type: Research Article
ISSN: 0737-8831

Article
Publication date: 9 April 2018

Ambuj Sharma, Sandeep Kumar and Amit Tyagi

The presence of random noise as well as narrow band coherent noise makes the structural health monitoring a really challenging issue and to achieve efficient structural health…

Abstract

Purpose

The presence of random noise as well as narrow band coherent noise makes the structural health monitoring a really challenging issue and to achieve efficient structural health assessment methodology, very good extraction of noise and analysis of the signals are essential. The purpose of this paper is to provide optimal noise filtering technique for Lamb waves in the diagnosis of structural singularities.

Design/methodology/approach

Filtration of time-frequency information of multimode Lamb waves through the noisy signal is investigated in the present analysis using matched filtering technique and wavelet denoising methods. Using Shannon’s entropy criterion, the optimal wavelet function is selected and verification is made via the analysis of root mean square error of filtered signal.

Findings

The authors propose wavelet matched filter method, a combination of the wavelet transform and matched filtering method, which can significantly improve the accuracy of the filtered signal and identify relatively small damage, especially in enormously noisy data. Correlation coefficient and root mean square error are additionally computed for performance evaluation of the filters.

Originality/value

The present study provides detailed information about various noise filtering methods and a first attempt to apply the combination of the different techniques in signal processing for the structural health monitoring application. A comparative study is performed using the statistical tool to know whether filtered signals obtained through three different methods are acceptable and practicable for guided wave application or not.

Details

International Journal of Structural Integrity, vol. 9 no. 2
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 31 December 2021

Praveen Kumar Lendale and N.M. Nandhitha

Speckle noise removal in ultrasound images is one of the important tasks in biomedical-imaging applications. Many filtering -based despeckling methods are discussed in many…

Abstract

Purpose

Speckle noise removal in ultrasound images is one of the important tasks in biomedical-imaging applications. Many filtering -based despeckling methods are discussed in many existing works. Two-dimensional (2-D) transforms are also used enormously for the reduction of speckle noise in ultrasound medical images. In recent years, many soft computing-based intelligent techniques have been applied to noise removal and segmentation techniques. However, there is a requirement to improve the accuracy of despeckling using hybrid approaches.

Design/methodology/approach

The work focuses on double-bank anatomy with framelet transform combined with Gaussian filter (GF) and also consists of a fuzzy kind of clustering approach for despeckling ultrasound medical images. The presented transform efficiently rejects the speckle noise based on the gray scale relative thresholding where the directional filter group (DFB) preserves the edge information.

Findings

The proposed approach is evaluated by different performance indicators such as the mean square error (MSE), peak signal to noise ratio (PSNR) speckle suppression index (SSI), mean structural similarity and the edge preservation index (EPI) accordingly. It is found that the proposed methodology is superior in terms of all the above performance indicators.

Originality/value

Fuzzy kind clustering methods have been proved to be better than the conventional threshold methods for noise dismissal. The algorithm gives a reconcilable development as compared to other modern speckle reduction procedures, as it preserves the geometric features even after the noise dismissal.

Details

International Journal of Intelligent Unmanned Systems, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2049-6427

Keywords

Book part
Publication date: 23 December 2005

William Ocasio and John Joseph

Macro- and microorganizational perspectives on strategy processes are typically treated as distinct lines of inquiry. This paper proposes an attention-based theory (March & Olsen

Abstract

Macro- and microorganizational perspectives on strategy processes are typically treated as distinct lines of inquiry. This paper proposes an attention-based theory (March & Olsen, 1976; Ocasio, 1997) of strategy formulation processes to bridge both perspectives. In particular, it links evolutionary perspectives on strategy (Burgelman, 1991, 2002) and strategic choice (Child, 1972) perspectives on organizational and strategic decision making (Bower, 1970; Carter, 1971; Cyert & March, 1963; Frederickson, 1986). Our treatment of the strategy process extends theory by viewing strategy processes as assemblages of tightly and loosely coupled networks of operational and governance channels (Allison & Zelikow, 1999; Ocasio, 1997), strategy formulation as a fluid and distributed process, and environmental, organizational level and individual level forces as consequential. Like Lovas and Ghoshal (2000), we view strategy formulation as a process of guided evolution. Unlike Lovas and Ghoshal who view strategic intent as the objective function that guides evolution, we view strategy formulation processes as more fragmented and contested, with multiple foci of attention, rather than an explicit objective function, and both top-down and bottoms-up processes capable of generating changes in the strategic direction of the firm.

Details

Strategy Process
Type: Book
ISBN: 978-1-84950-340-2

Open Access
Article
Publication date: 6 May 2014

Rachel Spacey, Louise Cooke, Adrienne Muir and Claire Creaser

The purpose of this paper is to review current knowledge, research and thinking about the difficulties facing public libraries offering internet access to their users in ensuring…

8655

Abstract

Purpose

The purpose of this paper is to review current knowledge, research and thinking about the difficulties facing public libraries offering internet access to their users in ensuring legally compliant and non-offensive use of this facility whilst still adhering to the professional value of freedom of access to information.

Design/methodology/approach

A range of recently published sources (1997-2013) relating to the technical and organisational measures used to manage public internet access primarily in public libraries in the UK with some limited international examples were reviewed and analysed. This work was undertaken as the underpinning research for an AHRC-funded project, MAIPLE (Managing Access to the internet in Public Libraries).

Findings

The provision of public internet access is a well-established component of the role of public libraries, but is seen as a potential problem due to the possibility of misuse, and it appears that simplistic technical solutions have disappointed. Legislation increases the need for more effective solutions that can provide a balance between the need for legal compliance, a welcoming environment for users, and the protection of key freedoms. A range of measures are being adopted worldwide in response to this dilemma.

Originality/value

Research exploring internet access in public libraries and its management in the UK is numerically small and much of it dates back to the start of the twenty-first century. This review presents a comprehensive analysis of the available literature and is of relevance to practitioners and academics in the fields of public librarianship.

Details

Journal of Documentation, vol. 70 no. 3
Type: Research Article
ISSN: 0022-0418

Keywords

Article
Publication date: 28 November 2018

Man Chen, Yong Zhong, Zhendong Li and Jin Wu

This paper aims to investigate a novel shape from focus (SFF) algorithm based on maximum correntropy Kalman filtering (SFF-MCKF) for solving the problem that traditional SFF…

Abstract

Purpose

This paper aims to investigate a novel shape from focus (SFF) algorithm based on maximum correntropy Kalman filtering (SFF-MCKF) for solving the problem that traditional SFF methods are weak in de-noising and spatial continuity.

Design/methodology/approach

To be specific, it was first assumed that the predicted depth of next pixel is equal to the depth of the current pixel according to spatial continuity. Besides, the observing data are derived from the estimation of traditional SFF and the corresponding covariance of noise is adaptively calculated by the entropy along the optical axis. Finally, to enhance robustness, we systematically conduct MCKF iteratively in four transfer directions that are 0°, 90°, 45° and −45°, respectively.

Findings

The experimental results indicate that the robustness of SFF-MCKF facing noises as well as the spatial continuity is better than that of the existing representative ones.

Research limitations/implications

As the proposed method is aimed at precision objects, high demand is for experimental device. Unstable device unregister the source images, which is unfavorable for observing data.

Originality/value

SFF-MCKF can be applied to many precision object measurements without significant drifts, such as the surface reconstruction of metal objects and electronic components. Besides, the computation cost is low, and SFF-MCKF has a wide range of real-time industrial applications.

Details

Sensor Review, vol. 39 no. 3
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 1 September 1989

G.J. Gilbey

In some respects, it is a pity that the filter‐pump i.e. the combination of a filter with a pump as a single unit, was ever devised. True, it reduces the plumbing of two separate…

Abstract

In some respects, it is a pity that the filter‐pump i.e. the combination of a filter with a pump as a single unit, was ever devised. True, it reduces the plumbing of two separate pieces of equipment and the manufacturer sells, in effect, two items where he might otherwise only sell one. But the existence of standard combined filter/pump units has taken away recognition by the user that he should specify not only the average flow‐rate required but also the effective filtering surface area since this directly relates to the frequency at which blocked media must be renewed in order to maintain that flow‐rate.

Details

Pigment & Resin Technology, vol. 18 no. 9
Type: Research Article
ISSN: 0369-9420

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