title: Colour image processing and texture analysis on images of porterhouse steak meat

authors: Streeter, Lee

subjects: meat imaging

abstract: This paper outlines two colour image processing and texture analysis techniques applied to meat images and assessment of error due to the use of JPEG compression at image capture. JPEG error analysis was performed by capturing TIFF and JPEG images, then calculating the RMS difference and applying a calibration between block boundary features and subjective visual JPEG scores. Both scores indicated high JPEG quality. Correction of JPEG blocking error was trialled and found to produce minimal improvement in the RMS difference. The texture analysis methods used were singular value decomposition over pixel blocks and complex cell analysis. The block singular values were classified as meat or non- meat by Fisher linear discriminant analysis with the colour image processing result used as ‘truth.’ Using receiver operator characteristic (ROC) analysis, an area under the ROC curve of 0.996 was obtained, demonstrating good correspondence between the colour image processing and the singular values. The complex cell analysis indicated a ‘texture angle’ expected from human inspection.

text: Colour image processing and texture analysis on images of porterhouse steak meat This paper outlines two colour image processing and texture analysis techniques applied to meat images and assessment of error due to the use of JPEG compression at image capture. JPEG error analysis was performed by capturing TIFF and JPEG images, then calculating the RMS difference and applying a calibration between block boundary features and subjective visual JPEG scores. Both scores indicated high JPEG quality. Correction of JPEG blocking error was trialled and found to produce minimal improvement in the RMS difference. The texture analysis methods used were singular value decomposition over pixel blocks and complex cell analysis. The block singular values were classified as meat or non- meat by Fisher linear discriminant analysis with the colour image processing result used as ‘truth.’ Using receiver operator characteristic (ROC) analysis, an area under the ROC curve of 0.996 was obtained, demonstrating good correspondence between the colour image processing and the singular values. The complex cell analysis indicated a ‘texture angle’ expected from human inspection.

year: 2005

title: A continuous 5300-yr Holocene cryptotephrostratigraphic record from northern New Zealand and implications for tephrochronology and volcanic-hazard assessment.

authors: Gehrels, Maria J.

subjects: crytotephra

abstract: A continuous  5280 calendar (cal.) yr long cryptotephrostratigraphic record of a peat core from northern New Zealand demonstrates that cryptotephra studies can enhance conventional tephra records by extending the known distribution of ash fall and enabling re-assessment of volcanic hazards. A systematic sampling strategy was used to locate peaks in glass-shard concentrations and to determine loci of individual geochemical populations, and a palynological method involving spiking samples with Lycopodium spores was adapted to facilitate accurate counting of glass-shard concentrations. Using glass shard major element compositions, and a core chronology based on eight AMS 14C ages and two visible macroscopic tephra layers, Taupo Tephra (Unit Y) (1688-1748 cal. BP) and Tuhua Tephra (6800-7230 cal. BP) (2cr-age ranges), four cryptotephras were correlated with known eruptions: Whakaipo (Unit V) (2743-2782 cal. BP), Stent (Unit Q) (4240-4510 cal. BP), and Unit K (4970-5290 cal. BP), erupted from Taupo Volcanic Centre, and Whakatane Tephra (5470-5600 cal. BP) erupted from Okataina Volcanic Centre. Mixed glass populations were found in the core, most likely an artefact of post-depositional remobilization of shards vertically (both up and down) in the peat or on its surface by wind, or a result of closely spaced eruption events, or a combination of these. A secondary glass population identified within the macroscopic Taupo Tephra was tentatively attributed to either an earlier phase within that eruption or to mixing with a slightly older Taupo-derived eruptive or (less likely) a currently unknown Okataina-derived eruptive. These results indicate that, in the absence of continuous cryptotephrostratigraphic analysis, a peak in shard concentrations may not in itself be indicative of the ‘true’ stratigraphic (ie, isochronous) level of a tephra layer. For cryptotephra studies of peat cores, we recommend (1) using a detailed sampling strategy for the analysis of distal tephra-derived glass to detect and account for any mixed populations and possible vertical spread of glass shards through the peat, and (2) analysing more shards from larger samples to help ‘capture’ sparsely represented cryptic andesitic tephra deposits.

text: A continuous 5300-yr Holocene cryptotephrostratigraphic record from northern New Zealand and implications for tephrochronology and volcanic-hazard assessment. A continuous  5280 calendar (cal.) yr long cryptotephrostratigraphic record of a peat core from northern New Zealand demonstrates that cryptotephra studies can enhance conventional tephra records by extending the known distribution of ash fall and enabling re-assessment of volcanic hazards. A systematic sampling strategy was used to locate peaks in glass-shard concentrations and to determine loci of individual geochemical populations, and a palynological method involving spiking samples with Lycopodium spores was adapted to facilitate accurate counting of glass-shard concentrations. Using glass shard major element compositions, and a core chronology based on eight AMS 14C ages and two visible macroscopic tephra layers, Taupo Tephra (Unit Y) (1688-1748 cal. BP) and Tuhua Tephra (6800-7230 cal. BP) (2cr-age ranges), four cryptotephras were correlated with known eruptions: Whakaipo (Unit V) (2743-2782 cal. BP), Stent (Unit Q) (4240-4510 cal. BP), and Unit K (4970-5290 cal. BP), erupted from Taupo Volcanic Centre, and Whakatane Tephra (5470-5600 cal. BP) erupted from Okataina Volcanic Centre. Mixed glass populations were found in the core, most likely an artefact of post-depositional remobilization of shards vertically (both up and down) in the peat or on its surface by wind, or a result of closely spaced eruption events, or a combination of these. A secondary glass population identified within the macroscopic Taupo Tephra was tentatively attributed to either an earlier phase within that eruption or to mixing with a slightly older Taupo-derived eruptive or (less likely) a currently unknown Okataina-derived eruptive. These results indicate that, in the absence of continuous cryptotephrostratigraphic analysis, a peak in shard concentrations may not in itself be indicative of the ‘true’ stratigraphic (ie, isochronous) level of a tephra layer. For cryptotephra studies of peat cores, we recommend (1) using a detailed sampling strategy for the analysis of distal tephra-derived glass to detect and account for any mixed populations and possible vertical spread of glass shards through the peat, and (2) analysing more shards from larger samples to help ‘capture’ sparsely represented cryptic andesitic tephra deposits.

year: 2006-02

title: Enacting Kaitiakitanga Challenges and Complexities in the Governance and Ownership of Rongoā Research Information.

authors: Boulton, Amohia

subjects: Indigenous

abstract: This article explores the tensions one research team has faced in securing appropriate governance or stewardship (which we refer to as kaitiakitanga) of research data. Whilst ethical and regulatory frameworks exist which provide a minimum standard for researchers to meet when working with Māori, what our experience has highlighted is there is currently a “governance” gap in terms of who should hold stewardship of research data collected from Māori individuals or collectives. In the case of a project undertaken in the traditional healing space, the organisation best placed to fulfil this governance role receives no funding or support to take on such a responsibility; consequently by default, this role is being borne by the research team until such time as capacity can be built and adequate resourcing secured. In addition, we have realised that the tensions played out in this research project have implications for the broader issue of how we protect traditional knowledge in a modern intellectual property law context, and once again how we adequately support those, often community-based organisations, who work at the interface between Indigenous knowledge and the Western world.

text: Enacting Kaitiakitanga Challenges and Complexities in the Governance and Ownership of Rongoā Research Information. This article explores the tensions one research team has faced in securing appropriate governance or stewardship (which we refer to as kaitiakitanga) of research data. Whilst ethical and regulatory frameworks exist which provide a minimum standard for researchers to meet when working with Māori, what our experience has highlighted is there is currently a “governance” gap in terms of who should hold stewardship of research data collected from Māori individuals or collectives. In the case of a project undertaken in the traditional healing space, the organisation best placed to fulfil this governance role receives no funding or support to take on such a responsibility; consequently by default, this role is being borne by the research team until such time as capacity can be built and adequate resourcing secured. In addition, we have realised that the tensions played out in this research project have implications for the broader issue of how we protect traditional knowledge in a modern intellectual property law context, and once again how we adequately support those, often community-based organisations, who work at the interface between Indigenous knowledge and the Western world.

year: 2014