Engineering: Journal Articles

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  • ItemOpen Access
    The Experiences of Endometriosis Patients with Diagnosis and Treatment in New Zealand
    (Frontiers Media SA, 2022) Ellis K; Wood R; Munro D
    Endometriosis is a chronically painful, invasive, inflammatory disease, with limited treatment options and long delays to diagnosis, which impacts 10% of females in New Zealand. Introduction: As part of a larger group discussion study, this paper covers three themes associated with endometriosis patient experiences: intensity of pain, diagnostic tool shortcomings and perspectives of treatment options. Materials and methods: The goal of this research was the inclusion of patient voices to guide research priorities. In early 2022, 50 New Zealand endometriosis patients participated in anonymous, asynchronous, text-based group discussions on the VisionsLive platform. The patients ranged in age from 18–48. The patients answered 50 questions, 23 text-based and 27 quantitative, and then took part in online group discussions. Results and discussion: The average age of symptom onset was 15.3 years, while the average delay from symptom onset to a working or surgically confirmed diagnosis was 7.91 years. The top five reported symptoms within the cohort were pain-based, and the participants discussed the many impacts of this pain on their work and education. The four main diagnostic tools employed on this cohort were abdominal ultrasound (72%), transvaginal ultrasound (68%), laparoscopy (82%) and sharing their symptom history with a medical practitioner (88%). The most common emotions patients experienced following receiving a diagnosis of endometriosis were relief (86%), feeling overwhelmed (54%), and anger (32%). The main treatments offered to this cohort were pain relief (96%), laparoscopic surgery (84%) and the combined oral contraceptive pill (80%). Of these three treatments, only laparoscopic surgery was viewed positively by the majority of users, with 67% considering laparoscopy an effective treatment, compared to 46% of users for pain relief, and 25% of users for the combined oral contraceptive pill. Conclusions: Gathering the voice of patients revealed that long delays to diagnosis and dismissal by medical practitioners frequently manifests as a reaction of relief by patients once diagnosed. Results also showed treatment options such as pain relief and hormonal medications were often considered ineffective, but were routinely offered as the first, or only, options for patients. It is therefore important that both quicker routes to diagnosis and more effective treatment options be developed.
  • ItemOpen Access
    The Perspectives of Māori and Pasifika Mate Kirikōpū (Endometriosis) Patients in Aotearoa New Zealand
    (MDPI AG, online-publication-date) Ellis K; Tewhaiti-Smith J; Munro, Deborah; Wood, Rachael
    Experiences with endometriosis have been understudied in indigenous and people of colour populations. This study aimed to investigate the experiences of Māori and Pasifika endometriosis patients in Aotearoa New Zealand. Twenty-seven Māori endometriosis participants from 21 iwi (tribes), and 10 Pasifika participants from 8 different island nations participated in online, asynchronous, anonymous text-based discussions about their endometriosis journeys. Their explanations were analysed qualitatively with an inductive thematic approach. The average delay from symptom onset to a confirmed or suspected endometriosis diagnosis was 11.6 ± 7.8 years in the Māori cohort and 12.4 ± 6.2 years in the Pasifika cohort. There were high levels of dissatisfaction with the availability of treatment, with 66.7% of Māori participants and 60.0% of Pasifika participants feeling that endometriosis treatment was not readily available to them. Poor experiences with the medical profession might dissuade Māori and Pasifika patients from seeking care, exacerbating a culture of distrust and perpetuating healthcare inequities. This could potentially be improved by increasing the capacity to take time for relationship building within general practice or through the incorporation of cultural advisors to support relationship establishment that emphasises holistic consideration of patient well-being and culturally safe care.
  • ItemOpen Access
    Mapping minor plantation species for New Zealand’s small-scale forests using Sentinel-2 satellite data
    (2022) Xu, Cong; Manley, Bruce; Ye, Ning
    Background: Relying solely on radiata pine (Pinus radiata D.Don) leaves New Zealand’s plantation forest industry vulnerable to fluctuations in market demand and at risk from a potentially devastating pest or disease outbreak. Therefore, the New Zealand government and forestry industry urge to diversify the forest resource and wood supply beyond the reliance on radiata pine. Unfortunately, the lack of accurate information on minor species’ area, composition, and location poses challenges to forecasting potential log supply and logistics planning. Methods: The objective of this study is to classify minor species in New Zealand using imagery and phenological features extracted from data collected by the Copernicus Sentinel-2 satellite. The study collected reference data of minor species from large-scale forest owners and applied Random Forest classification using Sentinel-2 imagery to classify nine minor species classes in the Hawke’s Bay region of New Zealand. Results: The study achieved an overall classification accuracy of 92.2% for minor species in New Zealand’s Hawke’s Bay region. Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and Eucalyptus species had the highest accuracies, exceeding 90% for both producer’s and user’s accuracies. Acacia, larch, and other mixed species had lower accuracies, likely due to their lower occurrence. The most important input variable for classification was the Digital Elevation Model, indicating the significance of elevation in differentiating plantation species. The Greenness Index (GI) and Red edge bands also proved useful in the classification. The phenological measure Mean-EVI2 was found useful in classifying deciduous species such as larch and poplar. Conclusions: To the best of our knowledge, this study is the first to map the spatial extent and distribution of minor plantation species in New Zealand at the regional level, providing promising results for potentially expanding the study to national-level species mapping.
  • ItemOpen Access
    Temporal dynamics of geothermal microbial communities in Aotearoa-New Zealand
    (Frontiers Media SA, 2023) Power , Jean F.; Lowe , Caitlin L.; Carere, Carlo; McDonald , Ian R.; Cary , S. Craig; Stott, Matthew
    Microbial biogeography studies, in particular for geothermal-associated habitats, have focused on spatial patterns and/or individual sites, which have limited ability to describe the dynamics of ecosystem behaviour. Here, we report the first comprehensive temporal study of bacterial and archaeal communities from an extensive range of geothermal features in Aotearoa-New Zealand. One hundred and fifteen water column samples from 31 geothermal ecosystems were taken over a 34-month period to ascertain microbial community stability (control sites), community response to both natural and anthropogenic disturbances in the local environment (disturbed sites) and temporal variation in spring diversity across different pH values (pH 3, 5, 7, 9) all at a similar temperature of 60–70°C (pH sites). Identical methodologies were employed to measure microbial diversity via 16S rRNA gene amplicon sequencing, along with 44 physicochemical parameters from each feature, to ensure confidence in comparing samples across timeframes. Our results indicated temperature and associated groundwater physicochemistry were the most likely parameters to vary stochastically in these geothermal features, with community abundances rather than composition more readily affected by a changing environment. However, variation in pH (pH ±1) had a more significant effect on community structure than temperature (±20°C), with alpha diversity failing to adequately measure temporal microbial disparity in geothermal features outside of circumneutral conditions. While a substantial physicochemical disturbance was required to shift community structures at the phylum level, geothermal ecosystems were resilient at this broad taxonomic rank and returned to a pre-disturbed state if environmental conditions re-established. These findings highlight the diverse controls between different microbial communities within the same habitat-type, expanding our understanding of temporal dynamics in extreme ecosystems.
  • ItemOpen Access
    Experimental Validation is Always Required for Molten Oxide Electrolysis Laboratory Crucibles
    (Springer Science and Business Media LLC, 2024) Ford K; Marshall, Aaron; Watson, Matthew; Bishop, Catherine
    Molten oxide electrolysis (MOE) is a promising electrochemical route to de-carbonize primary and secondary metal production. Developing MOE processes starts with laboratory experiments at temperatures > 1000∘C lasting ~10 hours and requiring long heating/cooling times to protect furnace hardware. Before investigating MOE processes, crucibles must be selected that tolerate the required temperatures while minimizing chemical interactions with the oxide to control melt contamination and contain the melt. Unfortunately no general procedure guiding MOE crucible selection is documented. Here we focus on laboratory crucibles in air for two MOE melts: titania-sodia at 1100∘C and neodymia-boria at 1300∘C . After shortlisting generic crucible materials using Ashby’s method, thermodynamic predictions were made for all-oxide titania-sodia charges using FactSage and cup test experiments were conducted on (i) all-oxide and carbonate charges for titania-sodia and (ii) neodymia-boria charges. While magnesia was predicted to be the best crucible for the titania-sodia melt, alumina was the best choice for both oxide and carbonate charges. The grain boundary networks of both magnesia and YSZ were infiltrated by the oxide and carbonate charges. Platinum was the best crucible for neodymia-boria melts. We show that compositional control during long, high-temperature MOE experiments requires experimental validation for specific chemistries every time.
  • ItemOpen Access
    Draft genome sequence of Thermococcus waiotapuensis WT1T, a thermophilic sulfur-dependent archaeon from the order Thermococcales
    (American Society for Microbiology, 2024) Manners , Sarah H.; Carere, Carlo; Dhami , Manpreet K.; Dobson, Renwick; Stott, Matthew; Stedman KM
    Thermococcus waiotapuensis WT1T is a thermophilic, peptide, and amino acid-fermenting archaeon from the order Thermococcales. It was isolated from Waiotapu, Aotearoa-New Zealand, and has a genome size of 1.80 Mbp. The genome contains 2,000 total genes, of which 1,913 encode proteins and 46 encode tRNA.
  • ItemOpen Access
    Thermophilic methane oxidation is widespread in Aotearoa-New Zealand geothermal fields
    (Frontiers Media SA, 2023) Houghton , Karen M.; Carere, Carlo; Stott, Matthew; McDonald , Ian R.
    Geothermal areas represent substantial point sources for greenhouse gas emissions such as methane. While it is known that methanotrophic microorganisms act as a biofilter, decreasing the efflux of methane in most soils to the atmosphere, the diversity and the extent to which methane is consumed by thermophilic microorganisms in geothermal ecosystems has not been widely explored. To determine the extent of biologically mediated methane oxidation at elevated temperatures, we set up 57 microcosms using soils from 14 Aotearoa-New Zealand geothermal fields and show that moderately thermophilic (>40°C) and thermophilic (>60°C) methane oxidation is common across the region. Methane oxidation was detected in 54% (n = 31) of the geothermal soil microcosms tested at temperatures up to 75°C (pH 1.5–8.1), with oxidation rates ranging from 0.5 to 17.4 μmol g−1 d−1 wet weight. The abundance of known aerobic methanotrophs (up to 60.7% Methylacidiphilum and 11.2% Methylothermus) and putative anaerobic methanotrophs (up to 76.7% Bathyarchaeota) provides some explanation for the rapid rates of methane oxidation observed in microcosms. However, not all methane oxidation was attributable to known taxa; in some methane-consuming microcosms we detected methanotroph taxa in conditions outside of their known temperature range for growth, and in other examples, we observed methane oxidation in the absence of known methanotrophs through 16S rRNA gene sequencing. Both of these observations suggest unidentified methane oxidizing microorganisms or undescribed methanotrophic syntrophic associations may also be present. Subsequent enrichment cultures from microcosms yielded communities not predicted by the original diversity studies and showed rates inconsistent with microcosms (≤24.5 μmol d−1), highlighting difficulties in culturing representative thermophilic methanotrophs. Finally, to determine the active methane oxidation processes, we attempted to elucidate metabolic pathways from two enrichment cultures actively oxidizing methane using metatranscriptomics. The most highly expressed genes in both enrichments (methane monooxygenases, methanol dehydrogenases and PqqA precursor peptides) were related to methanotrophs from Methylococcaceae, Methylocystaceae and Methylothermaceae. This is the first example of using metatranscriptomics to investigate methanotrophs from geothermal environments and gives insight into the metabolic pathways involved in thermophilic methanotrophy.
  • ItemUnknown
    A systematic mapping study of bug reproduction and localization
    (Elsevier BV, 2024) Wang , Di; Galster, Matthias; Morales-Trujillo , Miguel
    Context: Identifying the root cause of a software bug and fixing it is challenging. One reason for this is that many bugs are not reproducible during bug fixing. Objective: We aim to provide an overview of existing works on bug reproduction and localization. We ask four research questions: RQ1: What types of problems have been studied in the area of bug reproduction and localization? RQ2: How are problems studied in previous research? RQ3: What are the main findings and outcomes of previous studies? RQ4: What are the gaps and challenges identified in previous studies? Method: We conducted a systematic mapping study analyzing research literature published between 2011 and 2021. The search for primary studies involved four major computer science digital libraries and resulted in 134 studies for analysis. Results: Regarding RQ1 we found that many studies focus on information retrieval-based approaches to support bug reproduction and localization. Regarding RQ2 we found that bug reports and source code are the typical data sources of bug reproduction and localization. Also, most studies include experiments with historical data but do not investigate ongoing projects. Regarding RQ3 we found that many studies adapt or combine existing approaches for bug reproduction and localization to improve their accuracy or applicability (e.g., combine requirements-related information and bug reports to increase information-retrieval-based techniques). Regarding RQ4 we found that existing solutions for bug reproduction and localization have rarely been integrated into the workflow of developers. Conclusion: Although bug reproduction and localization have been studied in quite some detail, new challenges and gaps emerge due to the evolution of software technologies and practices and the practical needs of software developers. For example, bug reproduction approaches for traditional web applications do not work well with modern “Single Page Web Applications” (SPA) and related technologies, e.g., Angular or React.
  • ItemUnknown
    Augmented Reality in Learning Settings: A Systematic Analysis of its Benefits and Avenues for Future Studies
    (2024) Mohammadhossein N; Richter A; Lukosch, Stephan
    Despite its increasing use in various settings, Augmented Reality (AR) technology is still often considered experimental, partly due to a lack of clear understanding of the benefits of using AR. This study systematically reviews research on the use of AR in learning settings. Our analysis of 93 relevant articles offers 21 benefits related to the learning gains and outcomes of using AR. Our study shows that the positive effects of using AR on learners’ motivation and joy have been well-studied, whereas the effects on independent learning, concentration, spontaneous learning, critical thinking, and practical skills have not yet been examined in detail. Beyond classifying and discussing the benefits of using AR in learning settings, we elaborate avenues for future studies. We specifically point to the importance of conducting long-term studies to determine the value of using AR in learning beyond the initial novelty and exploring the integration of AR with other technologies.
  • ItemUnknown
    Investigation of nonlocal granular fluidity models using nuclear magnetic resonance
    (AIP Publishing, 2024) Clarke DA; Poata J; Galvosas P; Holland, Daniel
    Nonlocal rheology models describe features in granular flows, such as scale dependence and flow below the yield point, that are not captured by local rheology models. It has been proposed that these features may be described by the transport of a property known as the granular fluidity. In this article, we studied an annular Couette shear cell of lobelia seeds using nuclear magnetic resonance to collect detailed measurements of the velocity distribution and volume fraction. These data were used to study nonlocal granular rheology models. We found that the nonlocal granular fluidity model was capable of accurately describing the decay in the velocity profile along the shear gradient direction. We also measured the dimensionless fluidity and validated the general form of the relation between this quantity and the volume fraction.
  • ItemUnknown
    Eliciting real cravings with virtual food: Using immersive technologies to explore the effects of food stimuli in virtual reality
    (Frontiers Media SA, 2023) Harris , Nikita Mae; Lindeman, Robert; Bah , Clara Shui Fern; Gerhard, Daniel; Hoermann, Simon
    In this paper, we explore the current technical possibilities of eating in virtual reality (VR) and show how this could be used to influence eating behaviors. Cue-based exposure therapy is a well-known method used to treat eating disorders. There are several benefits to using VR in combination with cue-based therapy. However, before VR-based cue-exposure can be used for therapeutic purposes, the ability of the VR environment to elicit craving responses in participants must be assessed. This was the objective of the first part of the study, where we assessed whether our VR environment elicited food craving responses in participants. Results showed that our VR environment elicited food craving responses: Salivation Magnitude, Food Craving State and Urge to Eat was significantly different from the neutral baseline. In addition, results showed that food cravings measured through the salivation magnitude in response to the virtual condition were not significantly different from the real condition, thus showing that VR had a comparable effect on producing food cravings. The second part of the study was conducted to determine whether the addition of olfactory and interaction cues in VR increased the development of food cravings. The results of this part showed that adding synthetic olfactory cues, paired with visual cues, to our system, provided a significant further increase in food cravings. Our results demonstrate that the use of food cues in VR can increase the development of food cravings and that it is possible to provide a simple yet convincing eating experience in VR. Inevitably, food interaction in VR is still underexplored territory and further research is needed to improve utility and application in disciplines related to food and eating.
  • ItemOpen Access
    Evaluation of alternative carbon accounting categories for forestry in Gisborne District under the Emissions Trading Scheme
    (2022) Manley, Bruce; Xu , Cong (Vega); Visser , Rien
    In 2022, as part of Management Case Study, final-year Bachelor of Forestry Science students at the University of Canterbury re-mapped the small-scale forest estate in Gisborne District, estimated the delivered wood cost (DWC) at the time of harvesting and assessed the likelihood of harvesting. They also evaluated the profitability of afforestation under different carbon accounting approaches and categories.
  • ItemOpen Access
    Bandgap engineering of α-(AlxGa1-x)2O3 by a mist chemical vapor deposition two-chamber system and verification of Vegard's Law
    (AIP Publishing, 2018) Dang, Giang; Yasuoka T; Tagashira Y; Tadokoro T; Theiss W; Kawaharamura T
    This work reports growth of α-(AlxGa1-x)2O3 single crystals with high incorporation of Al by a Mist Chemical Vapor Deposition two-chamber system, which was rationally designed to avoid side-reactions between different precursors during solution preparation for multi-component thin film growth. Multiple acceleration voltages were used in Energy Dispersive X-ray measurements to reliably obtain the Al composition x of the films. As a result, Vegard's law for lattice constants was verified and found to be valid in the α-(AlxGa1-x)2O3 system. However, Vegard's law for optical bandgaps, derived from different models, required an additional term to account for the bowing effect. At x = 0.71, the gaps were 7.74, 7.03, 7.26, and 7.34 eV as derived from the Tauc plots for the direct bandgap, indirect bandgap, Tauc-Lorentz model, and O'Leary-Johnson-Lim model, respectively. The two-chamber system provides reliable and effective control of the Al content in α-(AlxGa1-x)2O3 alloys and heterostructures.
  • ItemOpen Access
    Recent Advances in Thermochemical Conversion of Woody Biomass for Production of Green Hydrogen and CO2 Capture: A Review
    (Elsevier BV, 2023) Pang, Shusheng
    Hydrogen as a green energy carrier has attracted great interests world-wide for substitution of fossil fuels and for abatement of the climate change concerns. However, green hydrogen from renewable resources is less than 0.1% at present in the world hydrogen production and this is largely from water electrolysis which is beneficial only when renewable electricity is used. Hydrogen production from diverse renewable resources is desirable. This review presents recent advances in hydrogen production from woody biomass through biomass steam gasification, producer gas processing and H2/CO2 separation. The producer gas processing includes steam-methane steam reforming (SMR) and water-gas shift (WGS) reactions to convert CH4 and CO in the producer gas to H2 and CO2. The H2 storage is also discussed using liquid carrier through hydrogenation are also discussed. The CO2 capture prior to the SMR is investigated to enhance H2 yield in the SMR and the WGS reactions.
  • ItemOpen Access
    Ensemble-Based Gradient Inference for Particle Methods in Optimization and Sampling
    (2023) Schillings , Claudia; Totzeck , Claudia; Wacker, Philipp
    We propose an approach based on function evaluations and Bayesian inference to extract higher-order differential information of objective functions from a given ensemble of particles. Pointwise evaluation of some potential V in an ensemble contains implicit information about first or higher order derivatives, which can be made explicit with little computational effort (ensemble-based gradient inference – EGI). We suggest to use this information for the improvement of established ensemble-based numerical methods for optimization and sampling such as Consensus-based optimization and Langevin-based samplers. Numerical studies indicate that the augmented algorithms are often superior to their gradient-free variants, in particular the augmented methods help the ensembles to escape their initial domain, to explore multimodal, non-Gaussian settings and to speed up the collapse at the end of optimization dynamics. The code for the numerical examples in this manuscript can be found in the paper’s Github repository
  • ItemOpen Access
    Quantitative Examination of the Anatomy of the Juvenile Sugar Maple Xylem
    (Public Library of Science (PLoS), 2023) Driller, Tenaya; Robinson, James; Clearwater M; Holland, Daniel; Van den Berg A; Watson, Matthew; Pereira FJ
    New methodologies have enabled viable sap yields from juvenile sugar maple trees. To further improve yields, a better understanding of sap exudation is required. To achieve this, the anatomy of the xylem must first be fully characterised. We examine juvenile maple saplings using light optical microscopy (LOM) and scanning electron microscopy (SEM), looking at sections cut along differing orientations as well as macerations. From this we measure various cell parameters. We find diameter and length of vessel elements to be 28 ± 8 μm and 200 ± 50 μm, for fibre cells 8 ± 3 μm and 400 ± 100 μm, and for ray parenchyma cells 8 ± 2 μm and 50 ± 20 μm. We also examine pitting present on different cell types. On vessel elements we observe elliptical bordered pits connecting to other vessel elements (with major axis of 2.1 ± 0.7 μm and minor 1.3 ± 0.3 μm) and pits connecting to ray parenchyma (with major axis of 4 ± 2 μm and minor 2.0 ± 0.7 μm). We observe two distinct pit sizes on fibres with circular pits 0.7 ± 0.2 μm in diameter and ellipsoidal pits 1.6 ± 0.4 μm by 1.0 ± 0.3 μm. We do not observe distinct pitting patterns on different fibre types. The various cell and pit measurements obtained generally agree with the limited data available for mature trees, with the exception of vessel element and fibre length, both of which were significantly smaller than reported values.
  • ItemOpen Access
    Driving change: Electric vehicle charging behavior and peak loading
    (Elsevier BV, 2024) Williams B; Bishop, Daniel; Hooper G; Chase, Geoff
    Electric vehicles (EVs) are projected to comprise 40 % of Aotearoa New Zealand's light vehicle fleet by 2040. However, charging decisions made by EV drivers, such as whether to charge immediately or delay charging, will affect peak electricity demand and lifetime of distribution network components. This study uses an agent-based model (ABM) of EV charging to investigate the effect of different EV penetration levels and owner charging decisions on components in New Zealand's residential electricity networks, although the methodology is wholly generalizable to other countries or regions. Monte Carlo simulation is performed for EV charging in a neighborhood of 71 houses, based on a representative residential distribution network, and simulated for 20 days. The key outcome measure is the rate of ‘Exceedance’ of the 300 kVA baseline transformer limit, where greater Exceedance entails shorter lifecycle and increased maintenance or capital costs to the provider. Results show delayed-charging algorithms (‘Altruistic charging’) decrease peak electricity demand and Exceedance, while drivers charging immediately (‘Selfish charging’) increases Exceedance. New Zealand's residential electricity networks are expected to accommodate a 40 % EV transition with 100 % Altruistic charging, as Exceedance is expected to increase less than 20 % from Exceedance without EVs. However, Selfish charging increases the rate of Exceedance by more than 250 %. Longer-term, increasing EV penetration and household electricity demand will require increased workplace charging infrastructure, electricity network upgrades, and/or automated and Internet of Things (IoT)-enabled Demand Side Management (DSM) of EV charging to avoid high rates of Exceedance and increased maintenance and replacement costs.
  • ItemOpen Access
    Zinc tin oxide metal semiconductor field effect transistors and their improvement under negative bias (illumination) temperature stress
    (AIP Publishing, 2017) Dang, Giang; Kawaharamura T; Furuta M; Allen, Martin
    © 2017 Author(s). Metal-semiconductor-field-effect-transistors (MESFETs) with silver oxide Schottky gates on zinc tin oxide (ZTO) channels showed fundamental differences in stability compared to conventional amorphous-oxide semiconductor thin-film-transistors (AOS-TFTs). The most severe negative-bias-temperature and negative-bias-illumination-temperature stress conditions, which usually degrade the performance of AOS-TFTs, significantly improved the switching characteristic of these ZTO MESFETs, producing devices with on:off current ratios, mobilities, and subthreshold swings of 8 × 106, 12 cm2 V−1 s−1, and 180 mV/dec, respectively. Further analysis confirmed that both negative bias and temperature (65 °C) were simultaneously required to produce this permanent effect that was linked to the electromigration of ionized donors from the MESFET depletion-region.
  • ItemOpen Access
    Interval analysis-based Bi-iterative algorithm for robust TDOA-FDOA moving source localisation
    (SAGE Publications, 2021) Qin N; Wang C; Shan C; Yang, Le
    In this study, an interval extension method of a bi-iterative is proposed to determine a moving source. This method is developed by utilising the time difference of arrival and frequency difference of arrival measurements of a signals received from several receivers. Unlike the standard Gaussian noise model, the time difference of arrival - frequency difference of arrival measurements are obtained by interval enclosing, which avoids convergence and initialisation problems in the conventional Taylor-series method. Using the bi-iterative strategy, the algorithm can alternately calculate the position and velocity of the moving source in interval vector form. Simulation results indicate that the proposed scheme significantly outperforms other methods, and approaches the Cramer-Rao lower bound at a sufficiently high noise level before the threshold effect occurs. Moreover, the interval widths of the results provide the confidence degree of the estimate.