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Auckland, New Zealand

Alam S.,University of Auckland | Dobbie G.,University of Auckland | Koh Y.S.,University of Auckland | Riddle P.,University of Auckland | Ur Rehman S.,Unitec Institute of Technology
Swarm and Evolutionary Computation

Optimization based pattern discovery has emerged as an important field in knowledge discovery and data mining (KDD), and has been used to enhance the efficiency and accuracy of clustering, classification, association rules and outlier detection. Cluster analysis, which identifies groups of similar data items in large datasets, is one of its recent beneficiaries. The increasing complexity and large amounts of data in the datasets have seen data clustering emerge as a popular focus for the application of optimization based techniques. Different optimization techniques have been applied to investigate the optimal solution for clustering problems. Swarm intelligence (SI) is one such optimization technique whose algorithms have successfully been demonstrated as solutions for different data clustering domains. In this paper we investigate the growth of literature in SI and its algorithms, particularly Particle Swarm Optimization (PSO). This paper makes two major contributions. Firstly, it provides a thorough literature overview focusing on some of the most cited techniques that have been used for PSO-based data clustering. Secondly, we analyze the reported results and highlight the performance of different techniques against contemporary clustering techniques. We also provide an brief overview of our PSO-based hierarchical clustering approach (HPSO-clustering) and compare the results with traditional hierarchical agglomerative clustering (HAC), K-means, and PSO clustering. © 2014 Elsevier B.V. Source

Galbraith M.,Unitec Institute of Technology
New Zealand Journal of Ecology

Tiritiri Matangi Island has attained an international profile as a successful ecological restoration project, and is often cited as a model of environmental stewardship. Ecological restoration on the island has always involved, and been dependent on, voluntary public involvement. Public participation in the project not only reinforces existing links between the public and scientific communities, but also facilitates even greater understanding of ecological concepts outside the professional and academic worlds. This paper examines enhanced ecological advocacy, ecological research and biodiversity management as outcomes of the collaborative involvement among the island's stakeholders, with 'public ecology' as an ultimate outcome. © New Zealand Ecological Society. Source

Stewart J.,Unitec Institute of Technology | Callagher P.,Marine Fisheries Research Services Ltd
Marine Policy

New Zealand's quota management system (QMS) was introduced in 1986 to enhance the sustainability of New Zealand's fishery. This paper examines trends in quota and catch share concentration across a range of important fish stocks. It demonstrates that continuing concentration is occurring in the ownership of quota for deepwater species. At the same time there has been an increase in participation by small scale fishers in the inshore fishery. This appears to be driven by the introduction of the Annual Catch Entitlement (ACE) regime, allowing annual catch shares to be accessed at reduced transaction cost. © 2011 Elsevier Ltd. Source

This study investigated the effect of the presence of introduced mongoose, environmental quality and habitat on the distribution of native and endemic birds on 16 small islands within Fiji. In total, 9055 birds representing 45 species were observed within four key habitats (forest, villages, crop land and coastal vegetation) on the 16 islands, half of which had mongoose present. Previous studies attribute bird declines and extirpation anecdotally to the mongoose. The presence of mongoose, environmental quality and habitat type had a measurable influence on observed extant native and endemic bird communities. We conclude that three ground birds; Gallirallus phillipensis, Anas supericiliosa and Porphyrio porhyrio were negatively influenced by the presence of mongoose and that Ptilinopus perousii, Phigys solitarius, Chrysoenas victor, Ducula latrans, Clytorhyrchus vitiensis, Pachycephala pectoralis, Prospeia tabunesis, and Foulehaio carunculata were particularly dependent on good quality forest habitat. Conservation priorities in relation to protecting Fiji's endemic birds from the effect of mongoose are discussed and preventative measures suggested. © 2013 Morley, Winder. Source

Poppe K.K.,University of Auckland | Doughty R.N.,University of Auckland | Whalley G.A.,University of Auckland | Whalley G.A.,Unitec Institute of Technology
European Heart Journal Cardiovascular Imaging

Current recommended reference ranges for echocardiographic measurements may not be relevant to the diverse world population they are applied to. A new study, the echocardiographic normal reference ranges of the left heart (EchoNoRMAL) study, is an individual person data meta-analysis of standard echocardiographic measurements which aims to re-define normal reference ranges of left heart dimensions, areas, volumes, mitral inflow and tissue Doppler, and associated calculated variables. © The Author 2012. Source

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