title: The effect of real and virtual construction field trips on students’ perception and career aspiration

authors: Seifan, Mostafa

abstract: To adequately prepare students for engineering practices, it is imperative that institutions adopt innovative methods of teaching, learning, and assessment. One such approach is the use of real field trips (RFT) to construction sites, which can enhance students’ perceptions of related careers. Although virtual field trips (VFTs) have emerged as a viable alternative—or supplement—to traditional field trips, little is known about their potential to provide the same or similar career exploration advantages. Using responses from a self-reported questionnaire administered to university students who participated in an RFT, this study sought to examine the usefulness of site visits in developing essential skills required for civil engineers. It also examines student perceptions on the use of VFTs as part of their university experience and the extent to which it could replace RFTs. The results indicate that students consider VFT as an enjoyable way to learn, given the possibilities facilitated by the new technology. However, notwithstanding its success, the students commonly opined that VFT was not a substitute for a RFT. From a holistic perspective, the issue is not whether VFTs can replace traditional field trips or not; it is rather the focus on identifying an integrated approach that combines lectures, and virtual and real field trips in a manner that supports a social constructivism mode of learning. Ultimately, this combination will enable students to effectively construct multiple links between lectures given in a hall and the real world outside.

text: The effect of real and virtual construction field trips on students’ perception and career aspiration To adequately prepare students for engineering practices, it is imperative that institutions adopt innovative methods of teaching, learning, and assessment. One such approach is the use of real field trips (RFT) to construction sites, which can enhance students’ perceptions of related careers. Although virtual field trips (VFTs) have emerged as a viable alternative—or supplement—to traditional field trips, little is known about their potential to provide the same or similar career exploration advantages. Using responses from a self-reported questionnaire administered to university students who participated in an RFT, this study sought to examine the usefulness of site visits in developing essential skills required for civil engineers. It also examines student perceptions on the use of VFTs as part of their university experience and the extent to which it could replace RFTs. The results indicate that students consider VFT as an enjoyable way to learn, given the possibilities facilitated by the new technology. However, notwithstanding its success, the students commonly opined that VFT was not a substitute for a RFT. From a holistic perspective, the issue is not whether VFTs can replace traditional field trips or not; it is rather the focus on identifying an integrated approach that combines lectures, and virtual and real field trips in a manner that supports a social constructivism mode of learning. Ultimately, this combination will enable students to effectively construct multiple links between lectures given in a hall and the real world outside.

year: 2020

title: Nature, Distribution, Origin and Economics of Glauconite in Carbonate-Phosphate-Glauconite Surficial Deposits on Central Chatham Rise, Southwest Pacific

authors: Lawless, Anna Shanti

subjects: Glauconite

abstract: Chatham Rise is a broad, elongated submarine platform that extends 1100 km out into the Southwest Pacific off eastern South Island. The surficial sediments on the central portion of the Rise at depths of 200-500 m include significant concentrations of the mineral glauconite (10-80 wt%) associated with skeletal carbonate, fine terrigenous material and locally abundant phosphatic nodules. This is the first study to fully analyse the nature, origin and economic potential of the glauconite component. Sub-bottom 3.5 kHz profiles have established the distribution, geometry and thickness (10-200 cm) of the surficial deposits, which overlie partially indurated Oligocene chalk of probable Whaingaroan age (~34-27 Ma). 137 grab, dredge or piston core samples have been analysed for their texture, mineralogy and geochemistry, which has produced a new surficial sediment map for the central Chatham Rise.

Glauconite most commonly occurs as dark green to black, very fine to fine sand-sized (0.2 mm), polished ovoidal and lobate pellets, and less commonly as infills within foraminiferal tests or as variably replaced rock fragments and phosphatic clasts. Full physical analysis reveals seven morphological types of glauconite including, in order of decreasing abundance, ovoidal, lobate, composite, internal molds, fossil casts, pigmentary, tabular and pellets within rock fragments. Their internal fabrics are dominated by random microcrystalline varieties with some oriented fibroradiating rim and skeletal infill types. Other notable features of some glauconite pellets include their expansion cracks, opaque inclusions and variable degrees of limonitisation. XRF/XRD analyses reveal mainly diagenetically mature varieties having elevated K2O (7-9 wt%) and Fe2O3 (19-23 wt%) values, and a dominant 10Å glauconitic mica structure involving from 10-20% expandable smectite layers.

K-Ar dates on pellets indicate a Late Miocene age (av. 5.75 Ma). This “old” age, as well as the clear evidence of reworking shown by the dominance of smooth polished ovoidal grains, mean that the central Chatham Rise glauconites are predominantly allogenic (i.e. derived/reworked), and neither strictly authigenic nor in situ, despite occurring in “modern” seafloor deposits. The formation of glauconite is linked to prominent upwelling within the Subtropical Front (STF) zone over the Rise in the Late Miocene, and the attendant heightened primary productivity, bacterial activity and nutrients associated with widespread biogenic blooms at that time. The source of the smectite required for glauconite formation could have been from the devitrification of volcanic ash from diverse eruptive centres, or through “neoformation”/authigenic precipitation within pore water solutions of carbonate-rich waters in the Oligocene/Miocene chalk substrate. Glauconite formation largely ceased after the Late Miocene due to an increase in terrigenous input, a reduced smectite source, and a major period of lowered sea level associated with Antarctic ice sheet growth. The “modern” Chatham glauconite pellets were sourced from submarine erosion of the former Late Miocene sediments and have been dispersed by intensified bottom current circulation at times of lowered sea level within the complex STF over Chatham Rise, and possibly ice scouring. Effectively there exists a widespread “Chatham unconformity” (mid-Oligocene to Recent) which cuts out most of the last 30 myr of the sedimentary record on central Chatham Rise, except for the highly condensed surficial deposits whose glauconite grains formed 5-6 Ma, in the Late Miocene. This long-lasting “Chatham unconformity” is a greatly extended version of the well documented Oligocene Marshall Paraconformity.

The thickness of the surficial sediment cover on central Chatham Rise ranges from 0.06-1.35 m. By using a conservative estimate of 0.5 m thick, and the wt% of glauconite within the sediment cover, a resource estimate of the glauconite has been made for various areas. In the most glauconite-rich area (>50 wt% glauconite) in the vicinity of Reserve Bank in 200-300 m water depths, which has an aerial extend of 4,500 km2, the glauconite resource amounts to about 2 Bt. The Chatham Rise glauconites have substantial economic potential as a potash fertiliser in support of the strong agricultural-based economy of New Zealand.

Glauconite is widespread in many Late Cretaceous-Cenozoic sedimentary deposits in the New Zealand rock record and the Chatham Rise occurrences provide a useful uniformitarian analogue for at least some of these.

text: Nature, Distribution, Origin and Economics of Glauconite in Carbonate-Phosphate-Glauconite Surficial Deposits on Central Chatham Rise, Southwest Pacific Chatham Rise is a broad, elongated submarine platform that extends 1100 km out into the Southwest Pacific off eastern South Island. The surficial sediments on the central portion of the Rise at depths of 200-500 m include significant concentrations of the mineral glauconite (10-80 wt%) associated with skeletal carbonate, fine terrigenous material and locally abundant phosphatic nodules. This is the first study to fully analyse the nature, origin and economic potential of the glauconite component. Sub-bottom 3.5 kHz profiles have established the distribution, geometry and thickness (10-200 cm) of the surficial deposits, which overlie partially indurated Oligocene chalk of probable Whaingaroan age (~34-27 Ma). 137 grab, dredge or piston core samples have been analysed for their texture, mineralogy and geochemistry, which has produced a new surficial sediment map for the central Chatham Rise.

Glauconite most commonly occurs as dark green to black, very fine to fine sand-sized (0.2 mm), polished ovoidal and lobate pellets, and less commonly as infills within foraminiferal tests or as variably replaced rock fragments and phosphatic clasts. Full physical analysis reveals seven morphological types of glauconite including, in order of decreasing abundance, ovoidal, lobate, composite, internal molds, fossil casts, pigmentary, tabular and pellets within rock fragments. Their internal fabrics are dominated by random microcrystalline varieties with some oriented fibroradiating rim and skeletal infill types. Other notable features of some glauconite pellets include their expansion cracks, opaque inclusions and variable degrees of limonitisation. XRF/XRD analyses reveal mainly diagenetically mature varieties having elevated K2O (7-9 wt%) and Fe2O3 (19-23 wt%) values, and a dominant 10Å glauconitic mica structure involving from 10-20% expandable smectite layers.

K-Ar dates on pellets indicate a Late Miocene age (av. 5.75 Ma). This “old” age, as well as the clear evidence of reworking shown by the dominance of smooth polished ovoidal grains, mean that the central Chatham Rise glauconites are predominantly allogenic (i.e. derived/reworked), and neither strictly authigenic nor in situ, despite occurring in “modern” seafloor deposits. The formation of glauconite is linked to prominent upwelling within the Subtropical Front (STF) zone over the Rise in the Late Miocene, and the attendant heightened primary productivity, bacterial activity and nutrients associated with widespread biogenic blooms at that time. The source of the smectite required for glauconite formation could have been from the devitrification of volcanic ash from diverse eruptive centres, or through “neoformation”/authigenic precipitation within pore water solutions of carbonate-rich waters in the Oligocene/Miocene chalk substrate. Glauconite formation largely ceased after the Late Miocene due to an increase in terrigenous input, a reduced smectite source, and a major period of lowered sea level associated with Antarctic ice sheet growth. The “modern” Chatham glauconite pellets were sourced from submarine erosion of the former Late Miocene sediments and have been dispersed by intensified bottom current circulation at times of lowered sea level within the complex STF over Chatham Rise, and possibly ice scouring. Effectively there exists a widespread “Chatham unconformity” (mid-Oligocene to Recent) which cuts out most of the last 30 myr of the sedimentary record on central Chatham Rise, except for the highly condensed surficial deposits whose glauconite grains formed 5-6 Ma, in the Late Miocene. This long-lasting “Chatham unconformity” is a greatly extended version of the well documented Oligocene Marshall Paraconformity.

The thickness of the surficial sediment cover on central Chatham Rise ranges from 0.06-1.35 m. By using a conservative estimate of 0.5 m thick, and the wt% of glauconite within the sediment cover, a resource estimate of the glauconite has been made for various areas. In the most glauconite-rich area (>50 wt% glauconite) in the vicinity of Reserve Bank in 200-300 m water depths, which has an aerial extend of 4,500 km2, the glauconite resource amounts to about 2 Bt. The Chatham Rise glauconites have substantial economic potential as a potash fertiliser in support of the strong agricultural-based economy of New Zealand.

Glauconite is widespread in many Late Cretaceous-Cenozoic sedimentary deposits in the New Zealand rock record and the Chatham Rise occurrences provide a useful uniformitarian analogue for at least some of these.

year: 2012

title: Diacritic Restoration and the Development of a Part-of-Speech Tagset for the Māori Language

authors: Cocks, John

subjects: Māori

abstract: This thesis investigates two fundamental problems in natural language processing: diacritic restoration and part-of-speech tagging. Over the past three decades, statistical approaches to diacritic restoration and part-of-speech tagging have grown in interest as a consequence of the increasing availability of manually annotated training data in major languages such as English and French. However, these approaches are not practical for most minority languages, where appropriate training data is either non-existent or not publically available. Furthermore, before developing a part-of-speech tagging system, a suitable tagset is required for that language. In this thesis, we make the following contributions to bridge this gap:

Firstly, we propose a method for diacritic restoration based on naive Bayes classifiers that act at word-level. Classifications are based on a rich set of features, extracted automatically from training data in the form of diacritically marked text. This method requires no additional resources, which makes it language independent. The algorithm was evaluated on one language, namely Māori, and an accuracy exceeding 99% was observed.

Secondly, we present our work on creating one of the necessary resources for the development of a part-of-speech tagging system in Māori, that of a suitable tagset. The tagset described was developed in accordance with the EAGLES guidelines for morphosyntactic annotation of corpora, and was the result of in-depth analysis of the Māori grammar.

text: Diacritic Restoration and the Development of a Part-of-Speech Tagset for the Māori Language This thesis investigates two fundamental problems in natural language processing: diacritic restoration and part-of-speech tagging. Over the past three decades, statistical approaches to diacritic restoration and part-of-speech tagging have grown in interest as a consequence of the increasing availability of manually annotated training data in major languages such as English and French. However, these approaches are not practical for most minority languages, where appropriate training data is either non-existent or not publically available. Furthermore, before developing a part-of-speech tagging system, a suitable tagset is required for that language. In this thesis, we make the following contributions to bridge this gap:

Firstly, we propose a method for diacritic restoration based on naive Bayes classifiers that act at word-level. Classifications are based on a rich set of features, extracted automatically from training data in the form of diacritically marked text. This method requires no additional resources, which makes it language independent. The algorithm was evaluated on one language, namely Māori, and an accuracy exceeding 99% was observed.

Secondly, we present our work on creating one of the necessary resources for the development of a part-of-speech tagging system in Māori, that of a suitable tagset. The tagset described was developed in accordance with the EAGLES guidelines for morphosyntactic annotation of corpora, and was the result of in-depth analysis of the Māori grammar.

year: 2012