Journal Articles

Permanent URI for this collectionhttps://mro.massey.ac.nz/handle/10179/7915

Browse

Filters

2012 - 201912020 - 20261

Settings

Subject: search.filters.subject.Network

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Resolving reticulate evolutionary histories of polyploid species of Azorella (Apiaceae) endemic to New Zealand
    (Elsevier Inc, USA, 2026-01) Ning W; Meudt HM; Nicolas AN; Plunkett GM; Heenan PB; Lee WG; Tate JA
    Genera with species of multiple ploidy levels provide models to understand successive rounds of whole genome duplication leading to intricate reticulate relationships of polyploid plant species. Here, we studied 17 polyploid taxa (species, subspecies, or varieties) in Azorella (Apiaceae) sections Schizeilema and Stilbocarpa that are mostly endemic to New Zealand. Using phylogenomic approaches, our goals were to resolve species relationships, determine the origins of the higher-level polyploids (6x and 10x), and assess the biogeography of the New Zealand Azorella species. Phylogenomic analysis of Anigosperms353 baits-captured Hyb-Seq data, together with comparison of phylogenies reconstructed using genome-skimming retrieved nrDNA and plastome sequences, showed that species diversification within New Zealand may relate to multiple origins from South America, which has been further shaped by additional rounds of polyploidy as well as hybridization or introgression. The two Azorella sections in New Zealand likely resulted from different biogeographic events from South America − one to the subantarctic islands (section Stilbocarpa) and a second to the South Island (section Schizeilema). In addition, within section Schizeilema, species have dispersed from the South Island (New Zealand) to Australia, the subantarctic islands, and the North Island (New Zealand). Our combined approach of phylogenomic analyses of plastome and nuclear locus-based data, together with SNP-based network approaches allowed us to determine the origins of some higher-level polyploids in New Zealand Azorella and revealed a more complex picture of historical and ongoing polyploidy and hybridization within these lineages.
  • Thumbnail Image
    Item
    A comprehensive simulation platform for switched reluctance generator system
    (World Scientific and Engineering Academy and Society, 2012) Arifin A; Al-Bahadly I; Mukhopadhyay SC; Topalis, FV; Dias, EM
    A Switched Reluctance Generator (SRG) system normally encompasses three main components: SR machine, controller and converter. On-going research on simulation and modelling of SRG system has focused on one component. There is a lack of a more comprehensive approach which integrates all three components into one simulation platform. We have developed a simulation model comprising SR machine, control and converter using MATLAB/Simulink. The main advantage of a simulation model is to reduce time and cost by having to perform changes on the prototype machine. In this paper, the work is focused on developing the optimal control algorithm for the platform. Optimal parameters are identified and characterized in terms of highest percentage of power generated. From simulation, the most influential parameters affecting the power generated are the firing angles and voltage level. So, a function relating the optimized parameter with machine performance was developed. The proposed control technique will provide easy implementation and ensure high machine performance. The effectiveness of the proposed method is demonstrated by simulation results. The work will aid in development of SRG by providing a platform to determine the best generating operation before real implementation, reducing manufacturing time and cost.