Revisiting the Power Co-ordination Challenges of the Original Snowy Mountains Scheme

The Snowy Mountains Scheme (1949–1972) was an Australian hydro-electricity generation triumph. However, the power co-ordination challenges were significant before the invention of fibre optic cable, as this historic paper from June 1964 attests.

Teachers’ Innovation and Learners’ Academic Achievement in Public Primary Schools in Marakwet East Sub- County, Kenya

Innovative and creative instruction is key towards helping learners in schools understand concepts being taught and perform well in their studies. One of the expectations from teacher performance appraisal and development (TPAD) is that teachers should make sure that they make their lessons to be innovative and creative in order for learners to develop knowledge and acquire required competencies. This paper looks at how teachers are using creativity and innovation in their teaching and its influence on learners’ academic achievement in public primary schools. The study was conducted in public primary schools in Marakwet East Sub County involving all teachers (581) and headteachers (83) employed by the Teachers Service Commission (TSC). A descriptive survey design was utilised for this investigation. A sample size representing 20.0% of respondents 17 head teachers and 117 teachers who were selected via a simple random sampling method. The instruments used to collect data consisted of questionnaires for teachers and interview schedules for headteachers. Data collected was analysed using quantitative and qualitative methods. The study found out that teachers’ use of creativity and innovation methods influenced learner academic achievement. However, the research found that the usage of ICT resources was low and this explains how very few teachers were accessing and utilising online resources for their learners. This means that despite teachers having the capacity to effectively make sure their classrooms experiences involve innovation and creativity is hampered by a lack of adequate infrastructure facilities like computers, laptops, internet, and electricity. In conclusion, teachers’ use of creativity and innovation approaches in teaching was found to influence the academic performance of learners in public primary schools in Marakwet East Sub County. The paper recommends that government needs to ensure that all schools are connected to the national grid of fibre optic cable and electricity

Towards the introduction of elements that contribute to the LRT operation sustainability through technology-based ancillary revenue

Transportation and technology innovation is one of the Sustainable Development Goals (SDGs) elements, and it has been outlined in goal number nine. The high demand for LRT usage requires a large amount of electricity. It contributes to the increase in electricity costs that have to be borne by LRT operators, and it is one of the main contributors to the increase in LRT operating costs. Revenue from fares unable to offset the rising operating cost. Therefore, LRT operators need to explore ancillary revenue activities to cover LRT operating costs. This paper aims to identify the elements involved in generating ancillary income through technology-based businesses from fibre optic cable networks along LRT alignment for the LRT operation sustainability. This study adopted semi-structured interviews for data collection and thematic analysis to analyse the data collected to identify the elements involved in generating ancillary revenue. Eleven themes were identified from the thematic analysis using NVivo. The list of elements involved has been proposed in this study has the potential to be a driver in generating ancillary revenue for the sustainability of LRT operations and contribute to sustainable development in achieving one of the objectives outlined in the SDGs.

Converging on an NBN future: Content, connectivity, and control – a symposium overview

In October 2012 the University of Canberra’s Faculty of Arts and Design hosted a public symposium on the topic of “Converging on an NBN Future: Content, Connectivity, and Control.” Featuring thirteen speakers from industry, government and academia, with input from an engaged audience, the symposium raised and discussed a variety of critical questions relating to the National Broadband Network (NBN) as it commences widespread operations in Australia. This paper provides an overview of symposium presentations, organised around common themes, and concludes with a summary of recommendations that emerged from the insights of presenters and the audience. While the symposium participants recognise the potential for change in the scope and scale of the NBN2 once the next federal parliamentary election has been concluded, discussion at the symposium focused on the current vision for the network, as a wholesale-only, open-access network providing fibre-optic cable connectivity to 93% of Australian premises, with the remaining 7% to be served by fixed wireless or satellite connectivity (Wong and Conroy 2010). At the time of the symposium the reference document guiding the development of the NBN was the 2012-2015 Corporate Plan (NBN Co Limited 2012). The government’s vision for realising the benefits of the National Broadband Network is set out in the 2011 National Digital Economy Strategy (Australian Government 2011).

Converging on an NBN future: Content, connectivity, and control – a symposium overview

In October 2012 the University of Canberra’s Faculty of Arts and Design hosted a public symposium on the topic of “Converging on an NBN Future: Content, Connectivity, and Control.” Featuring thirteen speakers from industry, government and academia, with input from an engaged audience, the symposium raised and discussed a variety of critical questions relating to the National Broadband Network (NBN) as it commences widespread operations in Australia. This paper provides an overview of symposium presentations, organised around common themes, and concludes with a summary of recommendations that emerged from the insights of presenters and the audience. While the symposium participants recognise the potential for change in the scope and scale of the NBN2 once the next federal parliamentary election has been concluded, discussion at the symposium focused on the current vision for the network, as a wholesale-only, open-access network providing fibre-optic cable connectivity to 93% of Australian premises, with the remaining 7% to be served by fixed wireless or satellite connectivity (Wong and Conroy 2010). At the time of the symposium the reference document guiding the development of the NBN was the 2012-2015 Corporate Plan (NBN Co Limited 2012). The government’s vision for realising the benefits of the National Broadband Network is set out in the 2011 National Digital Economy Strategy (Australian Government 2011).

On the comparison of strain measurements from fibre optics with a dense seismometer array at Etna volcano (Italy)

We demonstrate the capability of distributed acoustic sensing (DAS) to record volcano-related dynamic strain at Etna (Italy). In summer 2019, we gathered DAS measurements from a 1.5 km long fibre in a shallow trench and seismic records from a conventional dense array comprised of 26 broadband sensors that was deployed in Piano delle Concazze close to the summit area. Etna activity during the acquisition period gives the extraordinary opportunity to record dynamic strain changes (∼ 10−8 strain) in correspondence with volcanic events. To validate the DAS strain measurements, we explore array-derived methods to estimate strain changes from the seismic signals and to compare with strain DAS signals. A general good agreement is found between array-derived strain and DAS measurements along the fibre optic cable. Short wavelength discrepancies correspond with fault zones, showing the potential of DAS for mapping local perturbations of the strain field and thus site effect due to small-scale heterogeneities in volcanic settings.

Using Distributed Fibre Optic Sensing to Recover Well Integrity and Restore Production

Subject North Sea oil producing well has developed sustained casing pressure in the A-annulus, resulted in well being shut-in for around 3 years. Several attempts were made to understand the source of the tubing-to-annulus communication, however remediation actions based on the conventional intervention techniques were not successful, leak location was not isolated and sustained annular pressure remained. This resulted in deferral of oil production and costs incurred due to unsuccessful intervention and remediation techniques. As the well was already equipped with the permanent fibre optic cable for the communication with the downhole pressure gauge, an alternative opportunity was taken to detect leak location by repurposing the cable for the use of Distributed Acoustic Sensing (DAS) technology along with latest pattern recognition techniques. This approach is based on decoupling of fluid movement signature from the background noise and use pattern recognition algorithms to construct fluid flow logs across entire length of the fibre, displaying character and evolution of fluid noise through depth and time. Performed acquisition program allowed to activate the leak, presence of which was clearly visible on the wellhead and A-annulus pressure data. DAS-based acoustic flow logs allowed to clearly identify the exact location of the leak points and additionally provided an understanding to the reasons of failure of remediation methods based on the interpretation of conventional tool results. Remediation strategy based on the insights provided by DAS succeeded to isolate leak points with no further pressure build-up observed in the A-annulus. As a result, operator was able to return to production the well that has been shut-in for three years. This allowed to reinstate 1mbod in production, restore well primary barriers and reduce operational spend through cancellation of further well interventions. This technology offers a new method of acoustic data processing on DAS that extracts valuable insights to identify the source of fluid flow and flow pathways, providing an ability of capturing events behind multiple casing strings.

Wave-selective beamforming with Distributed Acoustic Sensing

<p>As fibre-optic DAS deployments become more common, researchers are turning to tried-and-true methods of locating or characterizing seismic sources such as beamforming. However, the strain measurement from DAS intrinsically carries its own sensitivities to both wave type and polarization (Martin et al. 2018, Paitz 2020 doctoral thesis). Additionally, a measurement along a conventional fibre-optic cable only provides one component of motion, and so certain azimuths may be blind to certain types of seismic sources, unless the cable layout can be designed to be oriented in multiple directions.</p><p>In this work, we explore the development and application of a beamforming algorithm that explicitly searches for multiple wavetypes. This builds on 3-component beamforming or Matched Field Processing (MFP) algorithms by Riahi et al. (2013), and Gal et al. (2018), where in addition to gridsearching over possible source azimuths, a distinct gridsearch is performed for each possible wavetype of interest. This does not solve the problem that a given cable orientation might be less sensitive to certain directions, but at least an array-response function can be robustly defined for each type of seismic excitation. This might help further distinguish whether beamforming observations are dominated by primary sources or by secondary scattering (van der Ende and Ampuero, 2020 preprint).</p><p>Much of this work uses analytic theory and synthetic examples. Time permitting, the enhanced algorithm will also be applied to data from the Mt. Meager experiment to explore its feasibility and efficacy with real data (EGU contribution from Klaasen et. al, 2021).</p>

Observing avalanche dynamics with Distributed Acoustic Sensing

<p><span>Avalanche research requires comprehensive measurements of sudden and rapid snow mass movement that is hard to predict. Automatic cameras, radar and infrasound sensors provide valuable observations of avalanche structure and dynamic parameters, such as velocity. Recently, seismic sensors have also gained popularity, because they can monitor avalanche activity over larger spatial scales. Moreover, seismic signals elucidate rheological properties, which can be used to distinguish different types of avalanches and flow regimes. To date, however, seismic instrumentation in avalanche terrain is sparse. This limits the spatial resolution of avalanche details, needed to characterise flow regimes and maximise detection accuracy for avalanche warning.</span></p><p><span>As an alternative to conventional seismic instrumentation, we propose Distributed Acoustic Sensing (DAS) to measure avalanche-induced ground motion. DAS is based on fibre-optic technology, which has previously been used already for environmental monitoring, e.g., of snow avalanches. Thanks to recent technological advances, modern DAS interrogators allow us to measure dynamic strain along a fibre-optic cable with unprecedented temporal and spatial resolution. It therefore becomes possible to record seismic signals along many kilometres of fibre-optic cables, with a spatial resolution of a few metres, thereby creating large arrays of seismic receivers. We test this approach at an avalanche test site in the Valleé de la Sionne, in the Swiss Alps, using an existing 700 m long fibre-optic cable that is permanently installed underground for the purpose of data transfer of other, independent avalanche measurements.</span></p><p><span>During winter 2020/2021, we recorded numerous snow avalanches, including several which reached the valley bottom, travelling directly over the cable during runout. The DAS recordings show clear seismic signatures revealing individual flow surges and various phases/modes that may be associated with roll waves and avalanche arrest. We compare our observations to state-of-the-art radar and seismic measurements which ideally complement the DAS data.</span></p><p><span>Our initial analysis highlights the suitability of DAS-based monitoring and research for avalanches and other hazardous granular flows. Moreover, the clear detectability of avalanche signals using existing fibre-optic infrastructure of telecommunication networks opens the opportunity for unrivalled warning capabilities in Alpine environments.</span></p>