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Article
Publication date: 30 March 2012

G.A. Gravvanis, P.I. Matskanidis, K.M. Giannoutakis and E.A. Lipitakis

The purpose of this paper is to propose novel parallel computational techniques for the parallelization of explicit finite element generalized approximate inverse methods, based…

346

Abstract

Purpose

The purpose of this paper is to propose novel parallel computational techniques for the parallelization of explicit finite element generalized approximate inverse methods, based on Portable Operating System Interface for UniX (POSIX) threads, for multicore systems.

Design/methodology/approach

The authors' main motive for the derivation of the new Parallel Generalized Approximate Inverse Finite Element Matrix algorithmic techniques is that they can be efficiently used in conjunction with explicit preconditioned conjugate gradient‐type schemes on multicore systems. The proposed parallelization technique of the Optimized Banded Generalized Approximate Inverse Finite Element Matrix (OBGAIFEM) algorithm is achieved based on the concept of the “fish bone” approach with the use of a thread pool pattern. Theoretical estimates on the computational complexity of the parallel generalized approximate inverse finite element matrix algorithmic techniques are also derived.

Findings

Application of the proposed method on a two‐dimensional boundary value problem is discussed and numerical results are given on a multicore system using POSIX threads. These results tend to become optimum and are favorably compared to corresponding results from multiprocessor systems, as presented in recent work by Gravvanis et al.

Originality/value

The proposed parallel explicit finite element generalized approximate inverse preconditioning, using approximate factorization and approximate inverse algorithms, is an efficient computational method that is valuable for computer scientists and for scientists and engineers in engineering computations.

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Article
Publication date: 1 April 2006

Konstantinos M. Giannoutakis and George A. Gravvanis

To propose novel parallel/distributed normalized explicit finite element (FE) approximate inverse preconditioning for solving sparse FE linear systems.

218

Abstract

Purpose

To propose novel parallel/distributed normalized explicit finite element (FE) approximate inverse preconditioning for solving sparse FE linear systems.

Design/methodology/approach

The design of suitable methods was the main objective for which several families of the normalized approximate inverse, based on sparse normalized approximate factorization, are produced. The main motive for the derivation of the new normalized approximate inverse FE matrix algorithmic techniques is that they can be efficiently used in conjunction with normalized explicit preconditioned conjugate gradient (NEPCG) – type schemes on parallel and distributed systems. Theoretical estimates on the rate of convergence and computational complexity of the NEPCG method are also derived.

Findings

Application of the proposed method on a three‐dimensional boundary value problem is discussed and numerical results for uniprocessor systems along with speed‐ups and efficiency for multicomputer systems are given. These results tend to become optimum, which are in qualitative agreement with the theoretical results presented for uniprocessor and distributed memory systems, using message passing interface (MPI) communication library.

Research limitations/implications

Further parallel algorithmic techniques will be investigated in order to improve the speed‐ups and the computational complexity of the parallel normalized explicit approximate inverse preconditioning.

Originality/value

The proposed parallel/distributed normalized explicit approximate inverse preconditioning, using approximate factorization and approximate inverse algorithms, is an efficient computational method that is valuable for computer scientists and for scientists and engineers in engineering computations.

Details

Engineering Computations, vol. 23 no. 3
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 18 June 2018

Efthimia Mavridou, Konstantinos M. Giannoutakis, Dionysios Kehagias, Dimitrios Tzovaras and George Hassapis

Semantic categorization of Web services comprises a fundamental requirement for enabling more efficient and accurate search and discovery of services in the semantic Web era…

249

Abstract

Purpose

Semantic categorization of Web services comprises a fundamental requirement for enabling more efficient and accurate search and discovery of services in the semantic Web era. However, to efficiently deal with the growing presence of Web services, more automated mechanisms are required. This paper aims to introduce an automatic Web service categorization mechanism, by exploiting various techniques that aim to increase the overall prediction accuracy.

Design/methodology/approach

The paper proposes the use of Error Correcting Output Codes on top of a Logistic Model Trees-based classifier, in conjunction with a data pre-processing technique that reduces the original feature-space dimension without affecting data integrity. The proposed technique is generalized so as to adhere to all Web services with a description file. A semantic matchmaking scheme is also proposed for enabling the semantic annotation of the input and output parameters of each operation.

Findings

The proposed Web service categorization framework was tested with the OWLS-TC v4.0, as well as a synthetic data set with a systematic evaluation procedure that enables comparison with well-known approaches. After conducting exhaustive evaluation experiments, categorization efficiency in terms of accuracy, precision, recall and F-measure was measured. The presented Web service categorization framework outperformed the other benchmark techniques, which comprise different variations of it and also third-party implementations.

Originality/value

The proposed three-level categorization approach is a significant contribution to the Web service community, as it allows the automatic semantic categorization of all functional elements of Web services that are equipped with a service description file.

Details

International Journal of Web Information Systems, vol. 14 no. 2
Type: Research Article
ISSN: 1744-0084

Keywords

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Article
Publication date: 25 February 2014

George A. Gravvanis and Christos K. Filelis-Papadopoulos

The purpose of this paper is to propose multigrid methods in conjunction with explicit approximate inverses with various cycles strategies and comparison with the other smoothers…

118

Abstract

Purpose

The purpose of this paper is to propose multigrid methods in conjunction with explicit approximate inverses with various cycles strategies and comparison with the other smoothers.

Design/methodology/approach

The main motive for the derivation of the various multigrid schemes lies in the efficiency of the multigrid methods as well as the explicit approximate inverses. The combination of the various multigrid cycles with the explicit approximate inverses as smoothers in conjunction with the dynamic over/under relaxation (DOUR) algorithm results in efficient schemes for solving large sparse linear systems derived from the discretization of partial differential equations (PDE).

Findings

Application of the proposed multigrid methods on two-dimensional boundary value problems is discussed and numerical results are given concerning the convergence behavior and the convergence factors. The results are comparatively better than the V-cycle multigrid schemes presented in a recent report (Filelis-Papadopoulos and Gravvanis).

Research limitations/implications

The limitations of the proposed scheme lie in the fact that the explicit finite difference approximate inverse matrix used as smoother in the multigrid method is a preconditioner for specific sparsity pattern. Further research is carried out in order to derive a generic explicit approximate inverse for any type of sparsity pattern.

Originality/value

A novel smoother for the geometric multigrid method is proposed, based on optimized banded approximate inverse matrix preconditioner, the Richardson method in conjunction with the DOUR scheme, for solving large sparse linear systems derived from finite difference discretization of PDEs. Moreover, the applicability and convergence behavior of the proposed scheme is examined based on various cycles and comparative results are given against the damped Jacobi smoother.

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Article
Publication date: 19 February 2024

Kashmira Ganji and Nikhat Afshan

In response to the growing interest in Internet of Things (IoT) technology and its profound implications for businesses and individuals, this bibliometric study focuses on a…

348

Abstract

Purpose

In response to the growing interest in Internet of Things (IoT) technology and its profound implications for businesses and individuals, this bibliometric study focuses on a critical yet understudied aspect, i.e. cybersecurity. As IoT adoption grows, so do concerns regarding user privacy and data security. This study aims to provide a comprehensive understanding of the current research in this vital area, shedding light on research trends, gaps and emerging themes.

Design/methodology/approach

The study conducted a bibliometric analysis and systematic review of literature spanning over two decades (2013–2023). Bibliometric analysis is conducted using Biblioshiny which is R-software-based advanced analytical tool. Further, VOSviewer is used to conduct network analysis. The study highlights the evolving landscape of IoT cybersecurity, emphasizing interdisciplinary intersections and the ethical dimensions of IoT technologies.

Findings

The study uncovers crucial concerns related to IoT adoption, emphasizing the urgent need for comprehensive cybersecurity protocols. It identifies emerging themes such as artificial intelligence and blockchain integration, indicating a shift toward interdisciplinary solutions. Furthermore, the research highlights ethical gaps in current IoT discussions, emphasizing the importance of responsible innovation.

Research limitations/implications

Businesses can bolster their cybersecurity strategies, policymakers can craft informed regulations and researchers are encouraged to explore IoT’s ethical dimensions.

Originality/value

This study pioneers a nuanced analysis of IoT cybersecurity, filling a crucial gap in the existing business and management literature. By synthesizing a decade of scholarly work, it provides foundational insights for researchers, businesses and policymakers. The research not only informs academic discourse but also offers practical guidance for enhancing IoT security measures and fostering ethical innovation.

Details

Journal of Science and Technology Policy Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2053-4620

Keywords

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Article
Publication date: 9 November 2020

Fuad Sameh Alshraiedeh and Norliza Katuk

Many REpresentational State Transfer (RESTful) Web services suffered from anti-patterns problem, which may diminish the sustainability of the services. The anti-patterns problem…

224

Abstract

Purpose

Many REpresentational State Transfer (RESTful) Web services suffered from anti-patterns problem, which may diminish the sustainability of the services. The anti-patterns problem could happen in the code of the programme or the uniform resource identifiers (URIs) of RESTful Web services. This study aims to address the problem by proposing a technique and an algorithm for detecting anti-patterns in RESTful Web services. Specifically, the technique is designed based on URIs parsing process.

Design/methodology/approach

The study was conducted following the design science research process, which has six activities, namely, identifying problems, identifying solutions, design the solutions, demonstrate the solution, evaluation and communicate the solution. The proposed technique was embedded in an algorithm and evaluated in four phases covering the process of extracting the URIs, implementing the anti-pattern detection algorithm, detecting the anti-patterns and validating the results.

Findings

The results of the study suggested an acceptable level of accuracy for the anti-patterns detection with 82.30% of precision, 87.86% of recall and 84.93% of F-measure.

Practical implications

The technique and the algorithm can be used by developers of RESTful Web services to detect possible anti-pattern occurrences in the service-based systems.

Originality/value

The technique is personalised to detect amorphous URI and ambiguous name anti-patterns in which it scans the Web service URIs using specified rules and compares them with pre-determined syntax and corpus.

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Article
Publication date: 28 November 2022

Preeti Khanna and Arunima Haldar

Blockchain technology is predicted by many to be the most disruptive technology which might bring accessibility, efficiency and transparency in the financial industry. This study…

881

Abstract

Purpose

Blockchain technology is predicted by many to be the most disruptive technology which might bring accessibility, efficiency and transparency in the financial industry. This study aims to understand the challenges likely to be faced by the Indian banking industry while adopting the technology.

Design/methodology/approach

The study adopted a qualitative approach to explore the challenges faced by the banking industry in India. Semi-structured in-depth interviews with senior executives and academicians in the finance and the information technology industries helped gain explorative insights about the challenges.

Findings

Thematic analysis suggested a framework comprising five challenges while adopting blockchain technology. These challenges relate to technology, organisation, operation, regulator and environmental context.

Originality/value

The paper contributes to the limited literature on the nascent blockchain technology adoption in banking industry in an emerging country context.

Details

Qualitative Research in Financial Markets, vol. 15 no. 2
Type: Research Article
ISSN: 1755-4179

Keywords

Available. Open Access. Open Access
Article
Publication date: 17 June 2024

Patrick Kraus, Julian Kappl and Dennis Schlegel

Due to the disruptive nature of digital transformation, firms can hardly ignore the further digitalisation of processes and business models. Implementing such initiatives triggers…

555

Abstract

Purpose

Due to the disruptive nature of digital transformation, firms can hardly ignore the further digitalisation of processes and business models. Implementing such initiatives triggers enormous investments in infrastructure and software, making the evaluation of digital investments crucial for a firm’s competitive situation.

Design/methodology/approach

Given the dynamics and uncertainties inherent in digital transformation, a qualitative, inductive research approach based on semi-structured interviews with high-level finance executives has been employed.

Findings

Our findings indicate widespread dissatisfaction with traditional investment appraisal methods for evaluating digital investments. Data also suggest that non-financial considerations are frequently taken into account, albeit implicitly, as participants struggled to clearly conceptualize these criteria.

Originality/value

The literature indicates important research gaps regarding the applicability and usage of traditional, predominantly financial, investment appraisal methods in digital contexts. This research enhances our understanding of digital investment evaluation, by (i) developing an exploratory conceptual framework of potential qualitative evaluation criteria and (ii) providing an in-depth and detailed understanding of the barriers to implementing investment appraisal methods.

Details

Digital Transformation and Society, vol. 3 no. 4
Type: Research Article
ISSN: 2755-0761

Keywords

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