39,454 results for 2010

  • Community Participation in Education: A Case Study in the Four Remote Primary Schools in Samlot District, Battambang Province, Cambodia

    To, Loeurt (2016)

    Masters thesis
    Victoria University of Wellington

    This study was conducted to investigate the nature of community participation in education in a remote district in Cambodia. A case study approach was used to explore the issue and employed mixed research methods for data collection. Epstein‘s participation and Bray‘s degree of community participation were used as analytical frameworks. The study contributes to a wide body of literature in participation in education, but which is under-researched for rural Cambodia. The study focussed on the forms and processes of participation by parents, community members and education stakeholders in primary schools in remote areas. The study discovered a range of social practices in community participation in education. The degrees of participation varied depending on the types of participation and the participants. Parents had direct participation in their children‘s learning at home, and indirect participation through resource contribution for school development. In addition, the community participated in education through their main representatives, the School Support Committees (SSCs). SSCs were found to possess power in the decision-making processes in school and education development. The most common type of participation was collaborative resource contribution for school development. This practice reflected the traditional culture of participation of Cambodian society but there was also a sign of behavioural change to focus more on children‘s learning. Teachers and School Support Committees were the drivers in bringing community and parents to participate in education. They were the facilitators, communicators, network connectors and mobilizers for school and education development. This case study suggests that a shift in focus (on the part of the government, non-governmental organizations and education stakeholders) to support parental involvement in children‘s learning, rather than the traditional resource mobilisation, may better promote children‘s learning. Further research on parental involvement in children‘s learning could be conducted.

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  • Spending Time: An investigation of the relationship between emotions, time and spending

    Liebenberg, Brett (2017)

    Masters thesis
    Victoria University of Wellington

    The significance of exchange within our daily lives encompasses not only the economic exchange of physical commodities but more abstract entities such as knowledge, skills and beliefs. This research investigation developed from a desire to understand my personal engagement with money and the design of money, through the exploration of shopping and spending habits. The activity of spending and everyday provisioning is one which has come to form a large component of our everyday lives and is partly informed by the non-economic aspects of exchange described above. This has led researchers, such as Daniel Miller (1998), to investigate the cultural phenomenon of consumerism. As our ability to consume has expanded to an almost unlimited wealth of products to choose from, a consumer has been able to form an imagined relationship with their purchases and may even regard it as a physical manifestation of various emotions. This level of constant spending and provisioning demands further examination, as the systems designed to enable us to consume are the same which have capitalised on our emotions. By making use of ethnographic methods of investigation (specifically interviews and qualitative survey tools), this research explores how an increased level of monetary literacy could be developed towards a consumers everyday spending. Through the design of a research tool, The Spending Map, a process of critical reflection is encouraged where it is possible to exhibit a dialogue that can capture, catalogue and critique the emotional engagement a consumer has towards their spending.

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  • Using Structural Geology and Cosmogenic Nuclide Dating to Infer the Slip Rate and Frictional Strength of the Active Mai’iu Low-Angle Normal Fault, Eastern Papua New Guinea

    Webber, Samuel (2017)

    Masters thesis
    Victoria University of Wellington

    Low-angle normal faults (LANFs) have induced debate due to their apparent non -Andersonian behaviour and lack of significant seismicity associated with slip. Dipping 21°/N, the Mai’iu Fault, located in the Woodlark Rift, Eastern Papua New Guinea is an active LANF that occupies a position at the transition between continental extension and seafloor spreading. Surface geomorphology indicates that the Mai’iu Fault scarp is not significantly eroded despite high rainfall and ~2900 m of relief. Based on modelling of regional campaign GPS data (Wallace et al., 2014) the Mai’iu Fault is thought to accommodate rapid (7–9 mm/yr) horizontal extension; however the slip rate of the Mai’iu Fault has not been directly validated. I use a range of methodologies, including field mapping, cosmogenic exposure dating, cosmogenic burial dating, and Mohr-Coulomb modelling, in order to provide new constraints on LANF strength and slip behaviour. I analyse the structure of conglomeratic strata within a back -rotated rider block atop the Mai’iu Fault surface. The Gwoira rider block is a large fault-bounded sedimentary rock slice comprising the Gwoira Conglomerate, located within a large synformal megamullion in the Mai’iu Fault surface. The Gwoira Conglomerate was originally deposited on the Mai’iu Fault hanging wall concurrent with extension, and has since been buried to a maximum depth of ~2 km (evidenced by modelling of vitrinite reflectance data, and structural analysis), back-tilted, and synformally folded. The Mai’iu Fault is also overlain by a large fault slice (the Gwoira rider block), that has been transferred from the previous LANF hanging wall to the current footwall by the initiation of the younger Gwoira Fault. Both the Gwoira Conglomerate (former hanging wall) and mylonitic foliation (footwall) of the Mai’iu Fault have been shortened ~E-W, perpendicular to the extension direction. I show that N-S trending synformal folding of the Gwoira Conglomerate was concurrent with on-going sedimentation and extension on the Mai’iu Fault. Structurally shallower Gwoira Conglomerate strata are folded less than deeper strata, indicating that folding was progressively accrued concurrent with ~N -S extension. I also show that abandonment of the inactive strand of the Mai’iu Fault in favour of the Gwoira Fault, which resulted in formation of the Gwoira rider block, occurred in response to progressive megamullion amplification and resultant misorientation of the inactive strand of the Mai’iu Fault. I attribute N-S trending synformal folding to extension-perpendicular constriction. This is consistent with numerous observations of outcrop-scale conjugate strike-slip faults that deform the footwall and hanging wall of the Mai’iu Fault (Little et al., 2015), and accommodate E-W shortening. Constrictional folding remains active in the near-surface as evidenced by synformal tilting of inferred Late Quaternary fluvial terraces atop the Gwoira rider block. In order to date this sequence of progressive constrictional folding, I have processed ten ²⁶Al/¹⁰Be terrestrial cosmogenic nuclide burial samples obtained from the Gwoira Conglomerate; unfortunately these data were not yet available at the time of printing, due to reasons outside of my control. I also present terrestrial cosmogenic nuclide (TCN) exposure ages for ten rock samples obtained from the lowermost Mai’iu Fault scarp at Biniguni Falls, in order to determine the Holocene slip-rate and style using cosmogenic ¹⁰Be in quartz. I model exposure age data after the approach of Schlagenhauf et al. (2011), using a Monte-Carlo simulation in which fault slip rate, the period of last slip on the fault, and local erosion rate are allowed to vary. Modelling evidences that the Mai’iu Fault at Biniguni Falls is active and slipping at 13.9±4.0 mm/yr (1σ), resolved over the last 13.2±2.7 ka (1σ). Modelling constrains the time of last slip to 2.9±1.4 ka (1σ); this is consistent with a seismic event at that time, followed by non-slip on the Mai’iu Fault until the present day. Finally, because rider block formation records abandonment of the uppermost part of a LANF, Coulomb fault mechanical analysis can be applied to field observations to provide an upper limit on LANF frictional strength (µf). Calculations are made in terms of Mohr-Coulomb mechanics, after the framework of Choi and Buck (2012). The lock-up (abandonment) orientation at any particular position on the Mai’iu Fault is principally a function of fault friction (µf), crustal friction (µc), fault cohesion (Cf), crustal cohesion (Cc), depth, fault orientation, fluid pressure, and the orientation of the greatest principle stress. Model results suggest that fault friction for the active Gwoira-Mai’iu Fault surface is 0.128≤μf≤0.265 for Cf<1.8 MPa. This suggests that past slip on the inactive Mai’iu Fault, and continued slip on the active Gwoira-Mai’iu Fault, were enabled by low fault frictional strength. I also model the strength of the active Mai’iu Fault at Biniguni Falls; results suggest greater LANF friction (μf≥0.32) than the Gwoira-Mai’iu Fault surface, and inactive Mai’iu Fault. In order to explain active slip on the LANF at Biniguni Falls concurrent with widespread field observations of outcrop-scale faulting of the LANF footwall, I suggest a process whereby overall the LANF remains viable and active, but locally stress conditions exceed the LANF abandonment criteria; this results in highly localised and temporary ‘footwall damage’ where the LANF footwall is locally dissected by outcrop-scale faulting.

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  • Travelling with the Spirit: Pentecostal Migration Religiosity Between Ghana and Australia

    Dennis, Dorcas (2017)

    Doctoral thesis
    Victoria University of Wellington

    The desire to migrate to foreign lands is widespread within contemporary Ghana. Among the Ghanaians, there is a growing sense that migrating overseas requires spiritual empowerment. Evidence of this development can be seen in the emergence of “passport and visa industries” that depend on the activities of a multitude of religious agents and ritual experts. Correspondingly, Ghanaian religious agents are now constantly generating new strategies designed to meet prospective migrants’ demands. The practice of enlisting the help of religious agents and practices for the purpose of international migration is having a marked effect on the Ghanaian religious landscape in two key ways: first, it has created a demand for religious agents who possess the power to solve migration-related spiritual problems; second, in response to this demand, Ghana's purveyors of spiritual powers have shaped their practices to inspire and enable migration. Using data from extensive fieldwork among members of the Church of Pentecost (CoP) and Power Chapel (PC) in Ghana and Australia, this thesis offers an account of the role of religious narratives and rituals in the experience of Ghanaians migrating abroad, and among Ghanaian migrants in Australia. The thesis argues that the present preoccupation with overseas migration, and its interconnection with religion, is creating a migration religiosity (MR) that inspires and enhances migrations, and which forms the basis for migrants’ extension of Ghanaian religions from the so-called global-South to the global-North. This MR operates in each phase of the migration experience. In the homeland, prospective migrants use MR to facilitate their international travel. On the journey, MR is the source of spiritual protection and safety. MR continues and takes on new roles as migrants use it in meeting new conditions and experiences in their new land. Migrants’ reliance on MR for place-making as they settle into their new lives in the diaspora motivates them to create worshiping Cells. These Cells become the setting in which Ghanaian migrants reformulate their religious traditions, and from which they launch proselytizing practices or reverse missions to the host community.

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  • New public management and information communication technology : organisational influences on frontline child protection practice

    Webster, Mike; McNabb, David (2016)

    Journal article
    Unitec

    In this paper the authors examine the new public management (NPM) philosophy influencing the organisational environment in which child protection social workers are located. NPM prioritises outputs through policies, such as results based accountability (RBA) predicated on the expectation that responsibility to achieve designated programme outcomes is sheeted to the agency and its workers. Ongoing funding depends on programme results. NPM ideology assumes that workers and managers in agencies tasked with delivering care and protection services are able to control the variables influencing outputs which contribute to outcomes. The authors will analyse four key aspects of NPM thinking (RBA, outputs, outcomes and key performance indicators) and explore their organisational consequences. The influence on social work practice of information and communications technology (ICT), on which NPM depends, is also considered. The paper is not an ideologically based rejection of NPM, but rather an assessment of its consequences for care and protection practice. The authors call for a return to the centrality of relationally based social work processes embodied in common factors (CF) practice, such as the therapeutic alliance. We argue that CF approaches offer a contrasting and more appropriate practice philosophy than NPM thinking while still enabling achievable, multifaceted organisational benefits.

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  • Housing issues in Auckland

    Haigh, David (2016-02)

    Journal article
    Unitec

    Recently, I went to hear Alan Johnson (Salvation Army Policy Analyst) speak on the topic of housing, and how Auckland itself got into this mess. Here are some of my thoughts on that speech. Alan Johnson started by asking how Government is failing Auckland and came up with four key points: Making promises that are not real promises Failing to come up with genuine ideas that will work Failing to understand Auckland and the governance of Auckland Being guilty of not caring

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  • The Prevalence of Postgraduate Education in Youth Health Among High School Clinicians and Associated Student Health Outcomes

    Denny, S; Farrant, B; Utter, J; Fleming, T; Bullen, P; Peiris-John, R; Clark, T (2016-11)

    Journal article
    The University of Auckland Library

    Purpose Despite numerous calls to improve training in adolescent health, there is little known about the prevalence or effectiveness of specialized training in adolescent health. Methods A two-stage random sampling cluster design was used to collect nationally representative data from 8,500 students from 91 high schools. Student data were linked to data from a survey of school health clinicians from participating schools on their level of training in youth health. Multilevel models accounting for demographic characteristics of students were used to estimate the association between nurses and physicians training in youth health and health outcomes among students. Results Almost all nurses and physicians reported some training in youth health, either having attended lectures or study days in youth health (n = 60, 80%) or completed postgraduate papers in youth health (n = 13, 17.3%). Students in schools where the nurses and physicians had received postgraduate training in youth health were less likely than students from schools with clinicians having attended lectures or study days in youth health to report emotional and behavior difficulties (11.8 vs. 12.7, p = .002) and binge drinking (19.6% vs. 24.9%, p = .03). There were no significant associations between depressive symptoms, suicide risk, cigarette, marijuana, contraception use, or motor vehicle risk behaviors among students and level of training among clinicians in their schools' health service. Conclusions Postgraduate training in youth health among nurses and physicians in school health services is associated with fewer students reporting mental health difficulties and binge alcohol use. These findings support specialized training in youth health for clinicians working predominantly with young people.

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  • Ultrasound assisted thermal pasteurization of beers with different alcohol levels: inactivation of Saccharomyces cerevisiae ascospores

    Milani, EA; Silva, FVM (2017-04)

    Journal article
    The University of Auckland Library

    The industrial production of beer ends with a process of pasteurization. This study investigated the ultrasound assisted thermal pasteurization of beer or thermosonication (TS), aiming the inactivation of Saccharomyces cerevisiae ascospores, the most resistant form of the yeast. The efficacy of 30 s TS in batch and continuous operation mode at 60, 65, and 70°C was studied. After that the ascospore inactivation in beers was modelled and TS pasteurization conditions recommended. Lastly, the inactivation of S. cerevisiae ascospores in beer by TS vs. thermal processing at 55°C was compared. Ultrasound alone and continuous TS operation were not enough to achieve the minimum beer pasteurization requirement aiming at S. cerevisiae spore inactivation. The TS survival curves were fitted with a Weibull model. TS at 50°C-1.9 min and TS at 55°C-26 s were enough for pasteurization, as opposed to 55°C-38 min thermal process. The results are helpful for designing appropriate thermosonication conditions to pasteurize beer with different alcohol contents and other beverages.

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  • Hongi Hika’s Self-Portrait

    Brown, Deidre (2016-06-01)

    Journal article
    The University of Auckland Library

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  • Gap junctions modulate seizures in a mean-field model of general anesthesia for the cortex

    Steyn-Ross, ML; Steyn-Ross, DA; Sleigh, James (2012-06)

    Journal article
    The University of Auckland Library

    During slow-wave sleep, general anesthesia, and generalized seizures, there is an absence of consciousness. These states are characterized by low-frequency large-amplitude traveling waves in scalp electroencephalogram. Therefore the oscillatory state might be an indication of failure to form coherent neuronal assemblies necessary for consciousness. A generalized seizure event is a pathological brain state that is the clearest manifestation of waves of synchronized neuronal activity. Since gap junctions provide a direct electrical connection between adjoining neurons, thus enhancing synchronous behavior, reducing gap-junction conductance should suppress seizures; however there is no clear experimental evidence for this. Here we report theoretical predictions for a physiologically-based cortical model that describes the general anesthetic phase transition from consciousness to coma, and includes both chemical synaptic and direct electrotonic synapses. The model dynamics exhibits both Hopf (temporal) and Turing (spatial) instabilities; the Hopf instability corresponds to the slow (≲8 Hz) oscillatory states similar to those seen in slow-wave sleep, general anesthesia, and seizures. We argue that a delicately balanced interplay between Hopf and Turing modes provides a canonical mechanism for the default non-cognitive rest state of the brain. We show that the Turing mode, set by gap-junction diffusion, is generally protective against entering oscillatory modes; and that weakening the Turing mode by reducing gap conduction can release an uncontrolled Hopf oscillation and hence an increased propensity for seizure and simultaneously an increased sensitivity to GABAergic anesthesia.

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  • Multiscale rescaled range analysis of EEG recordings in sevoflurane anesthesia

    Liang, Z; Li, D; Ouyang, G; Wang, Y; Voss, Logan; Sleigh, James; Li, X (2012-04)

    Journal article
    The University of Auckland Library

    OBJECTIVE: The Hurst exponent (HE) is a nonlinear method measuring the smoothness of a fractal time series. In this study we applied the HE index, extracted from electroencephalographic (EEG) recordings, as a measure of anesthetic drug effects on brain activity. METHODS: In 19 adult patients undergoing sevoflurane general anesthesia, we calculated the HE of the raw EEG; comparing the maximal overlap discrete wavelet transform (MODWT) with the traditional rescaled range (R/S) analysis techniques, and with a commercial index of depth of anesthesia - the response entropy (RE). We analyzed each wavelet-decomposed sub-band as well as the combined low frequency bands (HEOLFBs). The methods were compared in regard to pharmacokinetic/pharmacodynamic (PK/PD) modeling, and prediction probability. RESULTS: All the low frequency band HE indices decreased when anesthesia deepened. However the HEOLFB was the best index because: it was less sensitive to artifacts, most closely tracked the exact point of loss of consciousness, showed a better prediction probability in separating the awake and unconscious states, and tracked sevoflurane concentration better - as estimated by the PK/PD models. CONCLUSIONS: The HE is a useful measure for estimating the depth of anesthesia. It was noted that HEOLFB showed the best performance for tracking drug effect. SIGNIFICANCE: The HEOLFB could be used as an index for accurately estimating the effect of anesthesia on brain activity.

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  • Pharmacokinetics of dexmedetomidine combined with therapeutic hypothermia in a piglet asphyxia model

    Ezzati, M; Broad, K; Kawano, G; Faulkner, S; Hassell, J; Fleiss, B; Gressens, P; Fierens, I; Rostami, J; Maze, M; Sleigh, James; Anderson, B; Sanders, RD; Robertson, NJ (2014-07)

    Journal article
    The University of Auckland Library

    BACKGROUND: The highly selective α2 -adrenoreceptor agonist, dexmedetomidine, exerts neuroprotective, analgesic, anti-inflammatory and sympatholytic properties that may be beneficial for perinatal asphyxia. The optimal safe dose for pre-clinical newborn neuroprotection studies is unknown. METHODS: Following cerebral hypoxia-ischaemia, dexmedetomidine was administered to nine newborn piglets in a de-escalation dose study in combination with hypothermia (whole body cooling to 33.5°C). Dexmedetomidine was administered with a loading dose of 1 μg/kg and maintenance infusion at doses from 10 to 0.6 μg/kg/h. One additional piglet was not subjected to hypoxia-ischaemia. Blood for pharmacokinetic analysis was sampled pre-insult and frequently post-insult. A one-compartment linear disposition model was used to fit data. Population parameter estimates were obtained using non-linear mixed effects modelling. RESULTS: All dexmedetomidine infusion regimens led to plasma concentrations above those associated with sedation in neonates and children (0.4-0.8 μg/l). Seven out of the nine piglets with hypoxia-ischaemia experienced periods of bradycardia, hypotension, hypertension and cardiac arrest; all haemodynamic adverse events occurred in piglets with plasma concentrations greater than 1 μg/l. Dexmedetomidine clearance was 0.126 l/kg/h [coefficient of variation (CV) 46.6.%] and volume of distribution was 3.37 l/kg (CV 191%). Dexmedetomidine clearance was reduced by 32.7% at a temperature of 33.5°C. Dexmedetomidine clearance was reduced by 55.8% following hypoxia-ischaemia. CONCLUSIONS: Dexmedetomidine clearance was reduced almost tenfold compared with adult values in the newborn piglet following hypoxic-ischaemic brain injury and subsequent therapeutic hypothermia. Reduced clearance was related to cumulative effects of both hypothermia and exposure to hypoxia. High plasma levels of dexmedetomidine were associated with major cardiovascular complications.

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  • Open loop optogenetic control of simulated cortical epileptiform activity

    Selvaraj, P; Sleigh, James; Freeman, WJ; Kirsch, HE; Szeri, AJ (2014-06)

    Journal article
    The University of Auckland Library

    We present a model for the use of open loop optogenetic control to inhibit epileptiform activity in a meso scale model of the human cortex. The meso scale cortical model first developed by Liley et al. (2001) is extended to two dimensions and the nature of the seizure waves is studied. We adapt to the meso scale a 4 state functional model of Channelrhodopsin-2 (ChR2) ion channels. The effects of pulsed and constant illumination on the conductance of these ion channels is presented. The inhibitory cell population is targeted for the application of open loop control. Seizure waves are successfully suppressed and the inherent properties of the optogenetic channels ensures charge balance in the cortex, protecting it from damage.

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  • V. 'For now we see through a glass, darkly': the anaesthesia syndrome

    Sanders, RD; Absalom, A; Sleigh, JW; ConsCIOUS Group (2014-05)

    Journal article
    The University of Auckland Library

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  • Teacher narratives as theorisation of teaching: A Chinese teacher's perspectives on communicative language teaching (CLT)

    Bao, C; Zhang, Lawrence; Dixon, HR (2016)

    Journal article
    The University of Auckland Library

    Teaching as a profession is unique in that all the people who enter the profession have had extensive experience of it, which was built up over many years in classrooms as students. However, the pre-existing set of beliefs about teaching and learning, which were based on, and reinforced by, their own experiences, might cause perplexity for teachers who work in different cultural contexts. How to balance pedagogical principles becomes one of the important considerations for these teachers when faced with the perplexity. This study, therefore, was taken to explore the beliefs of a Chinese language teacher, who was educated in a traditional teaching system (three-centeredness) in Mainland China and was teaching Chinese to speakers of other languages (TCSOL) in New Zealand. It was aimed to unveil how a TCSOL teacher coped with such challenges. Narrative inquiry and thematic analysis were adopted in examining this teacher’s experience. Results show that composite factors impacted this teacher’s beliefs about teaching and learning. The research process and findings are expected to offer some implications for fostering effective TCSOL teachers’ professional development.

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  • Re: Is there an alternative to centralization for pancreatic resection in New Zealand?

    Windsor, JA; Pandanaboyana, S; Bartlett, ASJR (2016-09)

    Journal article
    The University of Auckland Library

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  • Carbon dioxide insufflation deflects airborne particles from an open surgical wound model

    Kokhanenko, P; Papotti, G; Cater, John; Lynch, AC; van der Linden, JA; Spence, Callum (2017-01)

    Journal article
    The University of Auckland Library

    Background Surgical site infections remain a significant burden on healthcare systems and may benefit from new countermeasures. Aim To assess the merits of open surgical wound CO2 insufflation via a gas diffuser to reduce airborne contamination, and to determine the distribution of CO2 in and over a wound. Methods An experimental approach with engineers and clinical researchers was employed to measure the gas flow pattern and motion of airborne particles in a model of an open surgical wound in a simulated theatre setting. Laser-illuminated flow visualizations were performed and the degree of protection was quantified by collecting and characterizing particles deposited in and outside the wound cavity. Findings The average number of particles entering the wound with a diameter of 95% and diminished rapidly above the wound to an atmospheric level (∼0%) at a height of 25 mm. Conclusion Airborne particles were deflected from entering the wound by the CO2 in the cavity akin to a protective barrier. Insufflation of CO2 may be an effective means of reducing intraoperative infection rates in open surgeries.

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  • Additive Manufacturing of High Resolution Embedded Electronic Systems

    Wasley, T; Li, J; Ta, D; Shephard, J; Stringer, Jonathan; Smith, P; Esenturk, E; Connaughton, C; Kay, R (2016)

    Conference item
    The University of Auckland Library

    Additive Manufacturing (AM) processes can facilitate the rapid iterative product development of electronic devices by optimising their design and functionality. This has been achieved by combining two additive manufacturing processes with conventional surface mount assembly to generate high resolution embedded multilayer electronic circuits contained within a 3D printed polymer part. Bottom-up DLP Stereolithography and material dispensing of isotropic conductive adhesives have been interleaved to deposit microscale features on photopolymer substrates. The material dispensing process has demonstrated the high density deposition of conductors attaining track widths of 134μm and produced interconnects suitable for directly attaching bare silicon die straight to the substrate. Interconnects down to a diameter of 149μm at a pitch of 457μm have been realized. In addition, this research developed a novel method for producing high aspect ratio z-axis connections. These were simultaneously printed with the circuit and component interconnects by depositing through-layer pillars with a maximum aspect ratio of 3.81. Finally, a method to accurately embed the packaged circuit layer within the printed part has been employed using bottom-up stereolithography.

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  • A theoretical and experimental investigation of roof flexibility on internal and net roof pressure dynamics in low-rise buildings with a dominant opening’

    Guha, TK; Sharma, Rajnish; Richards, Peter (2012)

    Journal article
    The University of Auckland Library

    A theoretical and experimental study of the effect of roof flexibility on the dynamics of internal and net roof pressure is reported in thsi paper. A two-degree-of-freedom dynamic model and its simplified counterpart, the single-degree-of-freedom quasi-static model is sued for theoretical analysis. As an illustrative example, admittance and spectra of internal and net roof pressure is presented for a medium-sized industrial building with different roof flexibilities using these models. Complementary wind tunnel investigations using a felixible Styrofoam roof are carried out to validate the model predictions. Additionally, effect of the dominant opening size and wind direction (i.e. angle of attack) on internal pressure for the flexible roof is experimentally investigated in the wind tunnel with a comparison to those for a rigid roof model.

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  • The significance of powder breakdown during conveying within industrial milk powder plants

    Boiarkina, Irina; Sang, C; Depree, N; Prince-Pike, Arrian; Yu, Wei; Wilson, DI; Young, BR (2016)

    Journal article
    The University of Auckland Library

    Instant whole milk powder is designed to rapidly dissolve in water, which depends on the particle size distribution (PSD). The fragile powder exiting the dryer is conveyed for packing which breaks down the particles, worsening the dissolution properties. This work investigated the effect of conveying on the final functional properties using two industrial plants with differing transport systems; a pneumatic system and bucket elevator. It was expected that the plant with the bucket elevator consistently produced powder with superior dissolution due to lower breakdown during transport. This was evaluated using the change in PSD. It was found that the plant with the bucket elevator had at least as large a change in the median particle size as the plant with the pneumatic transport system, contrary to the expectation. However, the plant with the bucket elevator had an initially larger particle size, and so the percentage of fine particles that negatively impact dissolution, remained low post transport. When quantified using the change in bulk density, having an initially low bulk density compensated for large increases in bulk density during conveying and powder with lower bulk density pre-transport showed better wettability post transport. Thus in order to produce powder with the desired functionalities the focus should be on improving the initial agglomeration and generating larger particles and lower bulk density pre-transport, as opposed to optimising the powder transport.

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