14,528 results for University of Canterbury Library

  • Digital Holographic Interferometry for Radiation Dosimetry

    Cavan, Alicia Emily (2015)

    Doctoral thesis
    University of Canterbury Library

    A novel optical calorimetry approach is proposed for the dosimetry of therapeutic radiation, based on the optical technique of Digital Holographic Interferometry (DHI). This detector determines the radiation absorbed dose to water by measurement of the refractive index variations arising from radiation induced temperature increases. The output consists of a time series of high resolution, two dimensional images of the spatial distribution of the projected dose map across the water sample. This absorbed dose to water is measured directly, independently of radiation type, dose rate and energy, and without perturbation of the beam. These are key features which make DHI a promising technique for radiation dosimetry. A prototype DHI detector was developed, with the aim of providing proof-of-principle of the approach. The detector consists of an optical laser interferometer based on a lensless Fourier transform digital holography (LFTDH) system, and the associated mathematical reconstruction of the absorbed dose. The conceptual basis was introduced, and a full framework was established for the measurement and analysis of the results. Methods were developed for mathematical correction of the distortions introduced by heat di usion within the system. Pilot studies of the dosimetry of a high dose rate Ir-192 brachytherapy source and a small eld proton beam were conducted in order to investigate the dosimetric potential of the technique. Results were validated against independent models of the expected radiation dose distributions. Initial measurements of absorbed dose demonstrated the ability of the DHI detector to resolve the minuscule temperature changes produced by radiation in water to within experimental uncertainty. Spatial resolution of approximately 0.03 mm/pixel was achieved, and the dose distribution around the brachytherapy source was accurately measured for short irradiation times, to within the experimental uncertainty. The experimental noise for the prototype detector was relatively large and combined with the occurrence of heat di usion, means that the method is predominantly suitable for high dose rate applications. The initial proof-of-principle results con rm that DHI dosimetry is a promising technique, with a range of potential bene ts. Further development of the technique is warranted, to improve on the limitations of the current prototype. A comprehensive analysis of the system was conducted to determine key requirements for future development of the DHI detector to be a useful contribution to the dosimetric toolbox of a range of current and emerging applications. The sources of measurement uncertainty are considered, and methods suggested to mitigate these. Improvement of the signal-to-noise ratio, and further development of the heat transport corrections for high dose gradient regions are key areas of focus highlighted for future development.

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  • The effects of clumped log distribution on line intersect sampling

    Tansey, Joshua (2014)

    Bachelors thesis
    University of Canterbury Library

    Line intersect sampling (LIS) is a method used for quantifying post-harvest waste. It is often used by forest managers to quantify merchantable volume remaining on the cutover so that compensation may be exacted under stumpage contracts. The theory has been extensively studied and will produce an accurate measure of harvest waste given the basic theoretical assumptions that: all logs are cylindrical, occur horizontally, are randomly orientated and randomly distributed. When these assumptions are violated, the method is not biased, although precision decreases substantially. A computer simulation was completed to determine whether or not the LIS method is appropriate, given a clumped distribution of logs produced by processing at central sites in cutover before using a forwarder to extract to the landing. The software ArcGIS with the application ModelBuilder was used to produce the LIS Model for running LIS assessments. It was determined through simulation that the conventional LIS method is not appropriate given these harvesting methods, as a level of bias was found in sampling determining that the LIS method underestimated true volume. T-tests confirmed the significance of this bias. LIS volume estimates were not precise, with the range of estimates ranging from 0 m3/ha to double the true volume. An increase in sampling length by a third was found to increase precision by only a small amount. Therefore, it was determine that increased sampling is not worthwhile as the costs associated with it do not justify the small increase in precision.

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  • Reducing the food stealing and pica of a young adult with multiple disabilities in respite care.

    van Eyk, Corrina Joanne (2015)

    Masters thesis
    University of Canterbury Library

    Problem behaviours occur in approximately 10 to 15% of individuals with intellectual disabilities and these behaviours most often include aggression and self-injury. Families who support young adults with multiple disabilities and problem behaviour at home often experience costs to their psychological, physical, financial and emotional wellbeing. Respite care evolved to allow families short breaks from care giving and to support families in looking after their family members at home. Furthermore, problem behaviour severely limits opportunities for individuals with multiple disabilities to interact adaptively with their environments and develop positive behaviour skills that increase the possibility of living independently in their adult years. The present study aimed first to demonstrate the utility of functional analysis of problem behaviour in respite care, and then, to reduce food stealing and pica exhibited by a young adult with multiple disabilities attending a respite care centre. Following a functional analysis that indicated food stealing and pica had the probable function of hunger reduction, two positive behaviour support plans were developed. These interventions, conducted at the respite centre three days a week by centre staff, involved strategies to teach the participant to sign “eat” in New Zealand Sign Language (NZSL) to gain access to food and increase accessibility of food in the environment to reduce pica. The results showed that introducing the NZSL sign reduced food stealing to near zero within three weeks and pica was eliminated following the combined approach of functional communication training and antecedent manipulation. Use of the communicative sign was maintained at follow-up and food stealing remained at near zero, while pica remained at zero one-month following the intervention.

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  • Exploring the Relationship Between Chocolate Cake-Related Guilt, Eating, and Individual Differences

    Castaneda Castellanos, Paola Maria (2015)

    Masters thesis
    University of Canterbury Library

    Food and eating are often associated with both positive and negative emotions: pleasure and enjoyment, and also worry and guilt. Guilt has the potential to have both adaptive and maladaptive consequences on health behaviours. The present study aimed to further explore the relationship between a default association of guilt with a ‘forbidden’ food item (i.e., chocolate cake) and healthy eating behaviours, attitudes, intentions, and perceived behavioural control. Individual difference variables (self-control, self-compassion, and neuroticism) and stress were also examined in relation to guilt. This study investigated the influence of a default guilt association on hypothetical and actual food choices. The findings suggest that food-related guilt can have both adaptive and maladaptive consequences on healthy eating behaviours and on individual difference variables. Individuals with chocolate cake-guilt associations reported healthier eating intentions and higher perceived behavioural control in relation to healthy eating. Those with guilt associations did not report more positive attitudes toward healthy eating nor higher self-control. They reported lower levels of self-compassion and higher levels of neuroticism and perceived stress. In regard to a hypothetical food choice, no differences were found between those with guilt or celebration associations. With one exception, guilt did not have adaptive effects during a taste test in regard to sweet and savoury food intake and post-eating guilt. Self-control appeared to be a protective factor from the maladaptive effects of guilt: self-control moderated the relationship between a guilt association and healthy eating intentions and savoury food intake. The overall findings from this research indicate that an alternative approach to promoting healthy eating and living should be considered.

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  • Do individual differences interact with lexical cues during speech recognition in adverse listening conditions?

    Kerr, Sarah Elizabeth (2015)

    Masters thesis
    University of Canterbury Library

    Purpose: This thesis examines the effect of listener characteristics (i.e., cognition and vocabulary) and language-based factors (i.e., lexical frequency and phonological similarity) on speech recognition accuracy in adverse listening conditions. Method: Fifty listeners (40 females and 10 males) aged 18-33 years and with normal hearing (puretone thresholds ≤ 20 dB HL, 0.25-8 kHz) participated. They completed a speech perception experiment, which required listeners to repeat back non-sensical English phrases presented at a variety of signal-to-noise ratios (-5, -2, +1, and +4 dB SNRs). In addition, all listeners undertook assessments of vocabulary knowledge (PPVT-IV) and cognition (WAIS -IV). The primary dependent variable was individual content word recognition accuracy, and results were analysed using binomial mixed effects modelling. Results: Listeners demonstrated variability in their speech recognition abilities, and their vocabulary and cognitive scores. Statistical analysis revealed that listener-based factors affected word recognition. Listeners with faster processing speed and larger working memories exhibited higher word recognition accuracy. Surprisingly, listeners with higher non-verbal intelligence scores exhibited lower word recognition accuracy. Vocabulary knowledge interacted with SNR, such that as the listening conditions became more favourable, listeners with larger receptive vocabularies identified more words correctly. Similarly, main effects were also present for language-based factors. The more phonologically distinct a word was, the more likely it was to be correctly identified; higher frequency words were more likely to be accurately recognised. In addition, higher frequency words were identified more accurately at higher SNR levels. Finally, listener- and language-based factors interacted. The positive effect of working memory on word recognition was reversed as word frequency increased; on the other hand non-verbal intelligence’s negative influence on word recognition was reversed as word frequency increased. Conclusion: In the current cohort, listener and language-based factors interacted in the process of word recognition in noise. These results provide an insight into the underlying speech recognition mechanisms in adverse conditions. Further understanding of how these listener differences affect an individual’s speech processing may lead to the development of improved signal processing techniques and rehabilitation strategies.

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  • ElectroFenton process applied to the degradation of an anti-inflammatory drugs mix using BDD electrodes

    Villanueva-Rodríguez, M.; Ruiz-Ruiz, E.; Bello-Mendoza, R. (2013)

    Conference Contributions - Other
    University of Canterbury Library

    Several micro-pollutants found in water and wastewaters have caused great concern because they represent a threat to aquatic organisms and the human health. Many of these compounds are pharmaceutical drugs such as the anti-inflamatories. Conventional wastewater treatment plants (WWTP) can not totally remove this kind of molecules. On the contrary, electrochemical advanced oxidation process such as electroFenton, are a potential alternative to degrade this compounds. Boron doped diamond (BDD) electrodes have proved to be effective for this purposes. This study was aimed at assessing the effectiveness of the electroFenton process with BDD electrodes sheets in an undivided cell to remove an anti-inflammatories mixture (naproxen, ibuprofen and diclofenac) in water. Here we present and compare preliminary results on the performance of this oxidation process in ultrapure water and WWTP final effluent. Reaction conditions like current density (40 mA cm-1) and Fe2+ concentration (3 mmol L-1) were established by surface response analysis. Degradation was followed by UVVis spectrophotometry and total organic carbon (TOC) measurements. Two initial concentrations were tested: low (LCL) and high (HCL) concentration level, with 5 mg L-1 and 50 mgL-1 each drug respectively. According to our results, the first 30 min, the absorbance keeps its value (Fig. 1a) in HCL and after that, occurs a value decrease (faster than LCL). It is maybe due to more organic radicals formed which participate in the oxidization. In TOC removal (Fig. 2b) after 2 hours, is reached a similar mineralization percent (90%) in all the cases. The organic matter present in the WWTP effluent affects lightly the absorbance and TOC removal (Fig 1a and 1b) in both levels. This process shown to be effective in two matrix and two concentration levels in relatively short time, which makes it attractive in the final WWTP´s treatment stages.

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  • The application of electrofenton and heterogeneous photocatalysis on the degradation of anti-inflammatory drugs mixture

    Alvarez del Castillo, M.; Villanueva-Rodríguez, M.; Ruiz-Ruiz, E.J.; Hinojosa-Reyes, L.; Hernández-Ramírez, A.; Bello-Mendoza, R. (2013)

    Conference Contributions - Other
    University of Canterbury Library

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  • Asymmetrical neutrino induced decay of nucleons

    Pons, D.J.; Pons, A.D.; Pons, A.J. (2015)

    Journal Articles
    University of Canterbury Library

    Copyright for this article is retained by the author(s), with first publication rights granted to the journal. This is an open-access article distributed under the terms and conditions of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/3.0/).

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  • Bio-inspired locomotion and control – A long march towards demanding applications, Keynote Speaker at 2014 International Conference on Robotic Welding and Intelligent Automation

    Chen, X.Q. (2014)

    Oral Presentations
    University of Canterbury Library

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  • Treatment of pulping water from coffee harvest by Fenton and electro-Fenton process

    Villanueva-Rodríguez, M.; Bello-Mendoza, R. (2012)

    Conference Contributions - Other
    University of Canterbury Library

    Introduction. In the initial coffee process exist two principal methods to remove the pulp and skin from cherries of coffee: dry method and the wet method . Wet processing consists of mechanical removal of exocarp in the presence of water using machine-pulping of the drupes , and this process requires a lot amount of water, which began after in wastewater. The pulping water contains high concentration of organic matter . This effluent is highly polluted with elevated chemical oxygen demand (COD), biochemichal oxygen demand (BOD) and suspended solids. Further influence over dissolved oxygen available and human health among people that live near to this water bodies, water pulping can affect aquatic life because of elevated acidity, strongly colored and occurrence of many toxic compounds present in coffee1,3. There are few studies about treatment of wastewater in coffee process ; and other studies employ commercial soluble coffee . The aim of this study is show the use of electrochemical process to mineralize and to reduce the color and organic matter on pulping water.

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  • Bioimprinted polymer platforms for cell culture using soft lithography

    Murray, L.M.; Nock, V.; Evans, J.J.; Alkaisi, M.M. (2014)

    Journal Articles
    University of Canterbury Library

    Background: It is becoming recognised that traditional methods of culture in vitro on flat substrates do not replicate physiological conditions well, and a number of studies have indicated that the physical environment is crucial to the directed functioning of cells in vivo. In this paper we report the development of a platform with cell-like features that is suitable for in vitro investigation of cell activity. Biological cells were imprinted in hard methacrylate copolymer using soft lithography. The cell structures were replicated at high nanometre scale resolution, as confirmed by atomic force microscopy. Optimisation of the methacrylate-based co-polymer mixture for transparency and biocompatibility was performed, and cytotoxicity and chemical stability of the cured polymer in cell culture conditions were evaluated. Cells of an endometrial adenocarcinoma cell line (Ishikawa) were cultured on bioimprinted substrates. Results: The cells exhibited differential attachment on the bioimprint substrate surface compared to those on areas of flat surface and preferentially followed the pattern of the original cell footprint. Conclusions: The results revealed for the first time that the cancer cells distinguished between behavioural cues from surfaces that had features reminiscent of themselves and that of flat areas. Therefore the imprinted platform will lend itself to detailed studies of relevant physical substrate environments on cell behaviour. The material is not degraded and its permanency allows reuse of the same substrate in multiple experimental runs. It is simple and does not require expensive or specialised equipment. In this work cancer cells were studied, and the growth behaviour of the tumour-derived cells was modified by alterations of the cells’ physical environment. Implications are also clear for studies in other crucial areas of health, such as wound healing and artificial tissues.

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  • Herschel-ATLAS: properties of dusty massive galaxies at low and high redshifts

    Rowlands, K.; Dunne, L.; Dye, S.; Aragon-Salamanca, A.; Maddox, S.; da Cunha, E.; Smith, D.J.B.; Bourne, N.; Eales, S.; Gomez, H.L.; Smail, I.; Alpaslan, M.; Clark, C.J.R.; Driver, S.; Ibar, E.; Ivison, R.J.; Robotham, A.; Smith, M.W.L.; Valiante, E. (2014)

    Journal Articles
    University of Canterbury Library

    We present a comparison of the physical properties of a rest-frame 250μm selected sample of massive, dusty galaxies from 0 < z < 5.3. Our sample comprises 29 high- redshift submillimetre galaxies (SMGs) from the literature, and 843 dusty galaxies at z < 0.5 from the Herschel -ATLAS, selected to have a similar stellar mass to the SMGs. The z > 1 SMGs have an average SFR of 390+80 −70M⊙yr−1 which is 120 times that of the low-redshift sample matched in stellar mass to the SMGs (SFR= 3.3 ± 0.2M⊙yr−1). The SMGs harbour a substantial mass of dust (1.2+0.3 −0.2×109M⊙), compared to (1.6± 0.1) × 108M⊙ for low-redshift dusty galaxies. At low redshifts the dust luminosity is dominated by the diffuse ISM, whereas a large fraction of the dust luminosity in SMGs originates from star-forming regions. At the same dust mass SMGs are offset towards a higher SFR compared to the low-redshift H-ATLAS galaxies. This is not only due to the higher gas fraction in SMGs but also because they are undergoing a more efficient mode of star formation, which is consistent with their bursty star-formation histories. The offset in SFR between SMGs and low-redshift galaxies is similar to that found in CO studies, suggesting that dust mass is as good a tracer of molecular gas as CO.

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  • Quantifying Spatial and Temporal Deposition of Atmospheric Pollutants in Runoff from Different Pavement Types

    Murphy, Louise Una (2015)

    Doctoral thesis
    University of Canterbury Library

    Urban development leads to increased impermeable landscapes that interrupt the hydrological cycle by creating an impermeable barrier to the natural infiltration of precipitation. Precipitate, unable to infiltrate, flows over impermeable surfaces as sheet runoff, carrying the pollutants from the land with it; thus comprising the quality of the stormwater. The runoff is redirected (frequently untreated) to nearby waterways altering their water quality and quantity, thereby, adversely affecting receiving aquatic ecosystems. Suspended solids and elevated heavy metal concentrations in stormwater are the leading causes of water quality degradation in urban waterways in New Zealand. It is widely reported that vehicles and metal roofs are a major direct source of the key pollutants (total suspended solids (TSS) and heavy metals) in stormwater runoff; however, the contribution of atmospheric deposition, as an indirect source, in stormwater runoff is rarely considered. This is principally due to the many uncertainties and challenges with measuring and managing these pollutants in stormwater runoff. Therefore, a monitoring programme into the dynamics controlling atmospherically derived pollutant build-up and wash-off from urban surfaces was conducted. In particular, this research focused on the spatial and temporal variability of Cu, Zn, Pb, and TSS deposition in different land-use areas; the influence of pavement type on atmospherically-deposited pollutant loads in stormwater; and the contribution of wet deposition and dry deposition to the total deposition loads. Impermeable concrete boards (≈ 1 m2) were deployed for 11 months in different land-use areas (industrial, residential and airside) in Christchurch, New Zealand, to capture spatially distributed atmospheric deposition loads in runoff over varying meteorological conditions. Mixed-effect regression models were developed to explain the influence of different meteorological characteristics on pollutant build-up and wash-off dynamics. Next, impermeable asphalt, permeable asphalt, impermeable concrete, and permeable concrete boards were deployed for two months in a residential land-use area to determine the influence of pavement composition and roughness on pollutant loads in stormwater. Finally, wet deposition samples were analysed in an industrial land-use area for 8 months to monitor the contribution of wet deposition to atmospherically-deposited pollutant loads. All samples were analysed for total and dissolved Cu, Zn, Pb, and TSS. Pavement type: Results showed that both impermeable and permeable concrete were efficient at retaining Cu and Zn. Bitumen leaching from the impermeable asphalt was a significant source of Zn to runoff. However, bitumen leaching from the permeable asphalt did not contain elevated Zn loads. Infiltrate from the permeable asphalt provided little/no removal of Cu and Zn. Impermeable asphalt provided greater retention of TSS and Pb over impermeable concrete because its rougher surface entrapped more particulates. TSS and Pb loads were the lowest from the permeable pavements due to the pavers filtering out particulates. Spatial variability: Results showed that all three land-use areas exhibited similar patterns of varying metal and TSS loads, indicating that atmospherically-deposited metals and TSS had a homogenous distribution within the Christchurch airshed. This suggested that the pollutants originated from a similar source and that the surrounding land-use was not an important factor in determining atmospheric pollutant loads to stormwater runoff. Although, higher pollutant loads were found for the industrial area, this was attributed to local topographic conditions rather than land-use activity. Temporal variability: Results illustrated the importance of antecedent dry days on pollutant build-up. Peak rainfall intensity and rain duration had a significant relationship with TSS and Pb wash-off; rain depth had a significant relationship with Cu and Zn wash-off. This suggested that the pollutant speciation phase plays an important role in surface wash-off. Rain intensity and duration influenced particulate pollutants, whereas, rain depth influenced dissolved pollutants. Additionally, mixed-effect models could predict approximately 53-69% of the variation in airborne pollutant loads in runoff. Deposition pathways: Wet deposition was an important contributor of dissolved Zn to stormwater runoff. However, dry deposition was the greatest source of total Cu, Zn, and Pb loads in stormwater runoff. This is principally due to the low annual rainfall in Christchurch limiting pollutant removal via wet deposition unlike dry deposition, which is continually occurring. Understanding the dynamics of airborne pollutant deposition and their contribution to stormwater pollution could help stormwater managers in strategic decision-making processes such as choice of location and installation of different treatment systems.

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  • A comparative study of mechanized cable harvesting systems in New Zealand

    Nuske, Samuel Ryan (2014)

    Bachelors thesis
    University of Canterbury Library

    Productivity and safety concerns of traditional cable harvesting systems have been the key drivers for increasing levels of mechanisation in New Zealand. The use of grapples in cable yarding could eliminate the need for motor-manual tree fallers and breaker-outs in most situations. A comparative time study was carried out on two mechanised cable harvesting systems utilising grapple carriages in an attempt to better understand the benefits and limitations of each system in different harvest settings. These systems include the Mechanical system which involved a swing yarder operating a mechanical grapple carriage and the Motorised system, which used a tower yarder with a motorised grapple carriage. The Mechanical system took less time to accumulate felled trees but took longer to unhook trees on the landing than the Motorised system. The Mechanical system had a shorter cycle time (2.07 minutes) than the Motorised system (2.32 minutes) and extracted 1.3 tonnes more than the Motorised system per cycle. The Motorised system had shorter cycle times when in horizontal haul distances of less than 90 metres, but had the longest times when the distance exceeded this. Utilisation rates were similar between the two systems, although the main difference in delays between the two systems was the use of surgepiles on the landing by the Motorised system. Both systems were effective, although on average the Mechanical system was more productive, with a productivity of 45 t/SMH, compared to 40 t/SMH for the Motorised system. The Mechanical system was the most productive when extracting mechanically felled and pre-bunched or trees while the Motorised system was the most productive when extracting motor-manually felled trees. Pre-bunching with an excavator was a more cost effective method than handing stems directly to the grapple carriage. Further research of the Mechanical system under more adverse conditions would allow a better overall comparison.

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  • Edaphic zoning and species-site matching to assist re-vegetation of indigenous species at the Styx Mill Reserve

    Campbell, Thornton (2014)

    Bachelors thesis
    University of Canterbury Library

    The Styx Mill Reserve is located in Belfast, Christchurch and is managed by the Christchurch City Council. Who aim to re-establish indigenous vegetation to large proportions of the area. These efforts have been successful in some sections of the Reserve; but large areas of the Reserve remain in grass and other weeds. The purpose of this investigation was to evaluate the presence of 5 hypothesised edaphic1 zones in a 10 ha study area, with a future aim of matching establishment practices to these edaphic sites. Findings indicated that all zones have significantly different vegetation and soil characteristics. Consequentially methods of native re-vegetation must be different in each zone if successful re-establishment of native species is to occur. Based on confirmed edaphic zones and client input, a site matched management plan and species list for one zone was developed. This aimed to increase the health and survival rates of plantings. Site modification followed techniques used at sites with similar conditions that have had successes in establishing woody vegetation. The effect of hydrogel on heath and survival levels was also trialled. To assess species suitability, five species were selected based on their abilities to survive the site conditions. Due to a combination of frost damage and ungulate browse, only totara survived and demonstrated good health scores. The frost factor is difficult to mitigate, hence species affected severely by frost are not recommended. The browse issue is easier to mitigate and it is felt that the two species heavily browsed, but not frosted are likely to be suitable. This resulted in ribbonwood, totara and kōhūhū being recommended. The time period did not allow assessment of the hydrogel treatment. Insufficient trial numbers exist to continue trials assessing future growth and survival rates over a longer time scale.

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  • The effect of plot co-registration error on the strength of regression between LiDAR canopy metrics and total standing volume in a Pinus radiata forest

    Slui, Benjamin Thomas (2014)

    Bachelors thesis
    University of Canterbury Library

    Background: The objective of this study was to verify the effect that plot locational errors, termed plot co-registration errors, have on the strength of regression between LiDAR canopy metrics and the measured total standing volume (TSV) of plots in a Pinus radiata forest. Methods: A 737 hectare plantation of mature Pinus radiata located in Northern Hawkes Bay was selected for the study. This forest had been measured in a pre-harvest inventory and had aerial LiDAR assessment. The location of plots was verified using a survey-grade GPS. Least square linear regression models were developed to predict TSV from LiDAR canopy metrics for a sample of 204 plots. The regression strength, accuracy and bias was compared for models developed using either the actual (verified) or the incorrect (intended) locations for these plots. The change to the LiDAR canopy metrics after the plot co-registration errors was also established. Results: The plot co-registration error in the sample ranged from 0.7 m to 70.3 m, with an average linear spatial error of 10.6 m. The plot co-registration errors substantially reduced the strength of regression between LiDAR canopy metrics and TSV, as the model developed from the actual plot locations had an R2 of 44%, while the model developed from the incorrect plot locations had an R2 of 19%. The greatest reductions in model strength occurred when there was less than a 60% overlap between the plots defined by correct and incorrect locations. Higher plot co-registration errors also caused significant changes to the height and density LiDAR canopy metrics that were used in the regression models. The lower percentile elevation LiDAR metrics were more sensitive to plot co- registration errors, compared to higher percentile metrics. Conclusion: Plot co-registration errors have a significant effect on the strength of regressions formed between TSV and LiDAR canopy metrics. This indicates that accurate measurements of plot locations are necessary to fully utilise LiDAR for inventory purposes in forests of Pinus radiata.

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  • Forest Industry Employees: training, safety and retention

    Muir, Kate Rosemary (2014)

    Bachelors thesis
    University of Canterbury Library

    Forestry employees are the most valuable asset to forest operations. An analysis was completed to determine employee training status, how safe employees feel within their roles and identify major reasons of dissatisfaction. Through the development of job descriptions and person specifications, it was possible to identify the job requirements along with the personal attributes and qualifications required by employers, to ensure employees were capable of undertaking their role. There is an identifiable gap within the level of formal education among employees. Over half (55%) of the employees have lower qualifications than those required to have undertaken further forestry on-job training. A majority of employees’, particularly those in machine operator roles feel safe in their forestry operational roles. A small proportion of employees in breaker out, thin to waste and pruning roles feel unsafe. All employees surveyed except loader operators, felt only moderately safe in their role. The difficult environment associated with forestry was determined to be the major reason for dissatisfaction (52%) among employees, along pay and length of day. Paradoxically, the environment was also a major reason for satisfaction among those surveyed. By identifying the major reasons of dissatisfaction among forestry employees it is possible to improve job satisfaction and employee retention. Training forestry employees needs to be from a more practical aspect. This will lead to increase the number of employees that are trained for the roles they are undertaking, by ensuring they are equipped with adequate knowledge, and have the skill to work safely and to a high quality standard.

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  • Dynamic behaviour of brain and surrogate materials under ballistic impact

    Soltanipour Lazarjan, Milad (2015)

    Doctoral thesis
    University of Canterbury Library

    In the last several decades the number of the fatalities related to criminally inflicted cranial gunshot wounds has increased (Aarabi et al.; Jena et al., 2014; Mota et al., 2003). Back-spattered bloodstain patterns are often important in investigations of cranial gunshot fatalities, particularly when there is a doubt whether the death is suicide or homicide. Back-spatter is the projection of blood and tissue back toward the firearm. However, the mechanism of creation of the backspatter is not understood well. There are several hypotheses, which describe the formation of the backspatter. However, as it is difficult to study the internal mechanics of formation of the backspatter in animal experiments as the head is opaque and sample properties vary from animal to animal. Performing ballistic experiments on human cadavers is rarely not possible for ethical reasons. An alternative is to build a realistic physical 3D model of the human head, which can be used for reconstruction of crime scenes and BPA training purposes. This requires a simulant material for each layer of the human head. In order to build a realistic model of human head, it is necessary to understand the effect of the each layer of the human head to the generation of the back-spatter. Simulant materials offer the possibility of safe, well‐controlled experiments. Suitable simulants must be biologically inert, be stable over some reasonable shelf‐life, and respond to ballistic penetration in the same way as the responding human tissues. Traditionally 10-20% (w/w) gelatine have been used as a simulant for human soft tissues in ballistic experiments. However, 10-20% of gelatine has never been validated as a brain simulant. Moreover, due to the viscoelastic nature of the brain it is not possible to find the exact mechanical properties of the brain at ballistic strain rates. Therefore, in this study several experiments were designed to obtain qualitative and quantitative data using high speed cameras to compare different concentrations of gelatine and new composite material with the bovine and ovine brains. Factors such as the form of the fragmentation, velocity of the ejected material, expansion rate, stopping distance, absorption of kinetic energy and effect of the suction as well as ejection of the air from the wound cavity and its involvement in the generation of the backspatter have been investigated. Furthermore, in this study a new composite material has been developed, which is able to create more realistic form of the fragmentation and expansion rate compared to the all different percentage of the gelatine. The results of this study suggested that none of the concentrations the gelatine used in this study were capable of recreating the form of the damage to the one observed from bovine and ovine brain. The elastic response of the brain tissue is much lower that observed in gelatine samples. None of the simulants reproduced the stopping distance or form of the damage seen in bovine brain. Suction and ejection of the air as a result of creation of the temporary cavity has a direct relation to the elasticity of the material. For example, by reducing the percentage of the gelatine the velocity of the air drawn into the cavity increases however, the reverse scenario can be seen for the ejection of the air. This study showed that elastic response of the brain tissue was not enough to eject the brain and biological materials out of the cranium. However, the intracranial pressure raises as the projectile passes through the head. This pressure has the potential of ejecting the brain and biological material backward and create back-spatter. Finally, the results of this study suggested that for each specific type of experiment, a unique simulant must be designed to meet the requirements for that particular experiment.

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  • Measuring Trust for Crowdsourced Geographic Information

    Severinsen, Jeremy John (2015)

    Masters thesis
    University of Canterbury Library

    In recent years Crowdsourced, or Volunteered, Geographic Information (CGI, VGI), has emerged as a large, up-to-date and easily accessible data source. Primarily attributable to the rise of the Geoweb and widespread use of location enabled technologies, this environment of widespread innovation has repositioned the role of consumers of spatial information. Collaborative and participatory web environments have led to a democratisation of the global mapping process, and resulted in a paradigm shift to the consumer of geographic data also acting as a data producer. With such a large and diverse group of participants actively mapping the globe, the resulting flood of information has become increasingly attractive to authoritative mapping agencies, in order to augment their own spatial data supply chains. The use of CGI would allow these agencies to undertake continuous improvement of their own data and products, adding a dimension of currency that has previously been unattainable due to high associated costs. CGI, however, through its diversity of authorship, presents a quality assurance risk to these agencies should it be included in their authoritative products. Until now, this risk has been insurmountable, with CGI remaining a “Pandora’s Box” which many agencies are reluctant to open. This research presents an algorithmic model that overcomes these issues, by quantifying trust in CGI in order to assess its implied quality. Labeled “VGTrust”, this model assesses information about a data author, its spatial trust, as well as its temporal trust, in order to produce an overall metric that is easy to understand and interpret. The VGTrust model will allow mapping agencies to harness CGI to augment existing datasets, or create new ones, thereby facilitating a targeted quality assurance process and minimizing risk to authoritativeness. This research proposes VGTrust in theory, on the basis of existing examinations of trust issues with CGI. Furthermore, a facilitated case study, “Building Our Footprints” is presented, where VGTrust is deployed to facilitate the capture of a building footprint dataset, the results of which revealing the veracity of the model as a measure to assess trust for these data. Finally, a data structure is proposed in the form of a “geo-molecule”, which allows the full spectrum of trust indicators to be stored a data structure at feature level, allowing the transitivity of this information to travel with each feature following creation. By overcoming the trust issues inherent in CGI, this research will allow the integration of crowdsourced and authoritative data, thereby leveraging the power of the crowd for productive and innovative re-use.

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  • Citizenship education and ‘Bildung’: Learning from “the Norwegian way” : a case study of teaching and learning democracy in a Norwegian junior high school.

    Plew, Elizabeth (2014)

    Masters thesis
    University of Canterbury Library

    How citizenship is taught in schools can have a profound impact on the development of young people’s ability and willingness to participate in public life. In turn, citizen participation has significant consequences for the health of a country’s democracy (Levine, 2003, Torney-Purta and Richardson, 2004, Osler and Starkey, 2006, Chawla, 2009, Hayward, 2012). Many established democracies today struggle with declining youth voter turnout and civic engagement (Levine, 2003, Catt, 2005, Gallego, 2009, Vowles, 2010, Blais and Rubenson, 2013). However Norway differs from many other democracies in that Norwegian students have one of the highest comparative rates of participation in different civic activities at school (Schulz et al., 2010). To help shed light on why Norway has been so effective at engaging young people in civic life, this thesis examined how democracy is taught in a Norwegian junior high school (ungdomsskole). The results of classroom observation, along with interviews with pupils, parents, administrators and teachers, indicate that deeply-held beliefs about the value of democracy underpin teacher practice alongside strong societal and parent support for citizenship education. This in-depth case study highlights the importance of a teaching philosophy based on a Norwegian interpretation of Bildung, an approach to education of the individual through discussion and action, so that individuals come to understand how they can contribute as citizens to the wider Norwegian polity. The case study suggests that the values of Bildung implicitly inform approaches of participatory learning, deliberation and teachers’ relationships with students, in ways which support young people as they in turn learn to value democracy. The research concludes that these experiences help to equip the ungdomsskole students observed in this case study with skills that they can use both immediately and in the future to participate as citizens in democratic processes and decision-making.

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