Ozlem Gemici Gunes and A. Sima Uyar
The purpose of this paper is to propose parallelization of a successful sequential ant‐based clustering algorithm (SABCA) to increase time performance.
Abstract
Purpose
The purpose of this paper is to propose parallelization of a successful sequential ant‐based clustering algorithm (SABCA) to increase time performance.
Design/methodology/approach
A SABCA is parallelized through the chosen parallelization library MPI. Parallelization is performed in two stages. In the first stage, data to be clustered are divided among processors. After the sequential ant‐based approach running on each processor clusters the data assigned to it, the resulting clusters are merged in the second stage. The merging is also performed through the same ant‐based technique. The experimental analysis focuses on whether the implemented parallel ant‐based clustering method leads to a better time performance than its fully sequential version or not. Since the aim of this paper is to speedup the time consuming, but otherwise successful, ant‐based clustering method, no extra steps are taken to improve the clustering solution. Tests are executed using 2 and 4 processors on selected sample datasets. Results are analyzed through commonly used cluster validity indices and parallelization performance metrices.
Findings
As a result of the experiments, it is seen that the proposed algorithm performs better based on time measurements and parallelization performance metrices; as expected, it does not improve the clustering quality based on the cluster validity indices. Furthermore, the communication cost is very small compared to other ant‐based clustering parallelization techniques proposed so far.
Research limitations/implications
The use of MPI for the parallelization step has been very effective. Also, the proposed parallelization technique is quite successful in increasing time performance; however, as a future study, improvements to clustering quality can be made in the final step where the partially clustered data are merged.
Practical implications
The results in literature show that ant‐based clustering techniques are successful; however, their high‐time complexity prohibit their effective use in practical applications. Through this low‐communication‐cost parallelization technique, this limitation may be overcome.
Originality/value
A new parallelization approach to ant‐based clustering is proposed. The proposed approach does not decrease clustering performance while it increases time performance. Also, another major contribution of this paper is the fact that the communication costs required for parallelization is lower than the previously proposed parallel ant‐based techniques.
Details
Keywords
Faqihza Mukhlish, John Page and Michael Bain
The purpose of this paper is to review the current state of proceedings in the research area of automatic swarm design and discusses possible solutions to advance swarm robotics…
Abstract
Purpose
The purpose of this paper is to review the current state of proceedings in the research area of automatic swarm design and discusses possible solutions to advance swarm robotics research.
Design/methodology/approach
First, this paper begins by reviewing the current state of proceedings in the field of automatic swarm design to provide a basic understanding of the field. This should lead to the identification of which issues need to be resolved in order to move forward swarm robotics research. Then, some possible solutions to the challenges are discussed to identify future directions and how the proposed idea of incorporating learning mechanism could benefit swarm robotics design. Lastly, a novel evolutionary-learning framework for swarms based on epigenetic function is proposed with a discussion of its merits and suggestions for future research directions.
Findings
The discussion shows that main challenge which is needed to be resolved is the presence of dynamic environment which is mainly caused by agent-to-agent and agent-to-environment interactions. A possible solution to tackle the challenge is by incorporating learning capability to the swarm to tackle dynamic environment.
Originality/value
This paper gives a new perspective on how to improve automatic swarm design in order to move forward swarm robotics research. Along with the discussion, this paper also proposes a novel framework to incorporate learning mechanism into evolutionary swarm using epigenetic function.
Details
Keywords
Dineshwar Ramdhony, Oren Mooneeapen and Ajmal Bakerally
This study investigates the effect of corporate governance mechanisms and country-level factors on the extent of Internet Financial Reporting (IFR). We used a sample of 106 listed…
Abstract
This study investigates the effect of corporate governance mechanisms and country-level factors on the extent of Internet Financial Reporting (IFR). We used a sample of 106 listed firms from five African countries. A financial reporting disclosure index was used to compute the aggregate IFR scores, which are made up of two components: content and presentation. Our results indicate that IFR relates to board size, firm size, country-level governance, economic development and index return. These results evidence the predominance of country-level factors over firm-specific factors in explaining the extent of IFR in Africa. It also shows that corporate governance mechanisms via board practices are insufficient to explain IFR in Africa. By further extending our analysis into the two components of IFR, we find that factors affecting the content and presentation dimensions are different. This study is among the first to investigate the extent of IFR in several African countries and adds to the existing evidence that has mainly focussed on firm-specific factors.
Details
Keywords
Anas Ali Al-Qudah and Asma Houcine
The purpose of the study is to investigate the factors that influence the adoption of new sustainability reporting (SDG) and external assurance (EXTA) practices. This study also…
Abstract
Purpose
The purpose of the study is to investigate the factors that influence the adoption of new sustainability reporting (SDG) and external assurance (EXTA) practices. This study also examines the relationship between sustainability reporting activity and corporate economic performance for a sample of 99 companies in Gulf Cooperation Council (GCC) countries that addressed SDGs in their sustainability reports published in 2019.
Design/methodology/approach
Using a two-stage analysis, this study examines how firms’ characteristics and corporate governance variables affect SDG and economic performance, as well as the firm’s decision to adopt EXTA statements for a sample of companies in that addressed SDGs in their sustainability reports published in 2019. The authors collected data from the Global Reporting Initiative’s (GRI) Sustainability Disclosure database and the Bureau van Dijk for Orbis database.
Findings
The results show that the variables firm size, profitability, big 4 auditors and government ownership significantly affect SDG and economic performance. The results also reveal that firms operating in the manufacturing sector are positively correlated with SDG and the firm’s decision to adopt EXTA statements. Furthermore, the results indicate that board independence positively affects SDGs and EXTA.
Research limitations/implications
The results can be particularly relevant and timely in helping large GCC companies promote their engagement to sustainable development practices by adopting more sustainable long-term strategies and policies. The findings could also guide managers in the strategic direction to identify firms’ characteristics and corporate governance features essential to promote sustainability reporting, an increasingly important performance indicator for investors and to enhance their confidence in the capital market. The results may also have practical implications to policymakers and other regulators in GCC countries to define effective frameworks that promote sustainable development reports and the use of EXTA.
Originality/value
The results make significant contributions by providing new insights to the existing literature on sustainability reporting in emerging markets by examining a unique perspective on the influence of firms’ characteristics and corporate governance features on the adoption of new sustainability reporting practices. The authors further add to the previous literature on the relationship between a firm’s economic performance and sustainable reporting by providing evidence from large companies in GCC countries, which might benefit from the adoption of multiple conceptual lenses, in this case, legitimacy and stakeholder theories. Lastly, through the empirical findings, this study provides economic validity to the 2018 joint initiative of the GRI and the United Nations Global Compact to strengthen corporate actions to achieve the United Nations SDGs.