Family tourism : a New Zealand COVID-19 perspective
- Yeoman, Ian, Schänzel, Heike, Zentveld, Elisa
- Authors: Yeoman, Ian , Schänzel, Heike , Zentveld, Elisa
- Date: 2022
- Type: Text , Journal article
- Relation: Journal of Tourism Futures Vol. 8, no. 2 (2022), p. 240-244
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- Description: Purpose: Because of COVID-19, tourist behaviour has changed with a range of trends becoming more prominent. This paper sets out to explain the dominance of family tourism in New Zealand's domestic markets and the trends associated with it. Design/methodology/approach: This paper is based upon secondary data from academic literature, industry reports, news media and webinars associated with New Zealand during COVID-19, starting in March 2020. Findings: The paper explains the rise of family tourism in New Zealand during COVID-19 based upon the consumer behaviour trends of: (1) Simplicity: In search of slow; (2) Mercurial consumption; (3) Localism; (4) Staycation; (5) Healthy habits; and (6) Is it safe to come out? Originality/value: The usefulness of this paper is derived from explaining why the rise of family tourism occurred based upon the identified trends. © 2022, Ian Seymour Yeoman, Heike A. Schänzel and Elisa Zentveld.
- Authors: Yeoman, Ian , Schänzel, Heike , Zentveld, Elisa
- Date: 2022
- Type: Text , Journal article
- Relation: Journal of Tourism Futures Vol. 8, no. 2 (2022), p. 240-244
- Full Text:
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- Description: Purpose: Because of COVID-19, tourist behaviour has changed with a range of trends becoming more prominent. This paper sets out to explain the dominance of family tourism in New Zealand's domestic markets and the trends associated with it. Design/methodology/approach: This paper is based upon secondary data from academic literature, industry reports, news media and webinars associated with New Zealand during COVID-19, starting in March 2020. Findings: The paper explains the rise of family tourism in New Zealand during COVID-19 based upon the consumer behaviour trends of: (1) Simplicity: In search of slow; (2) Mercurial consumption; (3) Localism; (4) Staycation; (5) Healthy habits; and (6) Is it safe to come out? Originality/value: The usefulness of this paper is derived from explaining why the rise of family tourism occurred based upon the identified trends. © 2022, Ian Seymour Yeoman, Heike A. Schänzel and Elisa Zentveld.
Having enough cultural food? A qualitative exploration of the experiences of migrants in a regional area of Australia
- Yeoh, Joanne, Lê, Quynh, Terry, Daniel, McManamey, Rosa
- Authors: Yeoh, Joanne , Lê, Quynh , Terry, Daniel , McManamey, Rosa
- Date: 2014
- Type: Text , Journal article
- Relation: Journal of Food Research Vol. 4, no. 2 (2014), p. 16
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- Description: The notion of food security encompasses the ability of individuals, households and communities to acquire food that is healthy, sustainable, affordable, appropriate and accessible. Despite Australia’s current ability to produce more food than required for its population, there has been substantial evidence demonstrating that many Australians struggle to feed themselves, particularly those from a cultural and linguistically diverse (CALD) background. This qualitative phenomenological study investigated the experiences of food security among migrants in a regional area of Australia (Tasmania). 33 semi-structured interviews were conducted with Tasmanian migrants. The interviews were analysed thematically using Nvivo 10.0 and three main themes emerged: (1) migrant’s experiences of food security in Tasmania; (2) the factors that influence migrant food security in Tasmania; and (3) acculturation strategies. Participants were satisfied with their current food security in Tasmania but they still encountered some challenges in the availability, accessibility and affordability of healthy and cultural food. Factors that influenced their food security were educational background, the language barrier, socioeconomic status, geographical isolation, and their cultural background. Migrants managed to adapt to the new food culture by using different acculturation strategies. Migrants residing in Tasmania encounter a diverse number of challenges pertaining to food security and use different food security strategies while acculturating to the new environment. These findings may inform other migrant communities in Australia, relevant non-government organisations and government departments and suggest strategies to address food security challenges among migrants.
- Authors: Yeoh, Joanne , Lê, Quynh , Terry, Daniel , McManamey, Rosa
- Date: 2014
- Type: Text , Journal article
- Relation: Journal of Food Research Vol. 4, no. 2 (2014), p. 16
- Full Text:
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- Description: The notion of food security encompasses the ability of individuals, households and communities to acquire food that is healthy, sustainable, affordable, appropriate and accessible. Despite Australia’s current ability to produce more food than required for its population, there has been substantial evidence demonstrating that many Australians struggle to feed themselves, particularly those from a cultural and linguistically diverse (CALD) background. This qualitative phenomenological study investigated the experiences of food security among migrants in a regional area of Australia (Tasmania). 33 semi-structured interviews were conducted with Tasmanian migrants. The interviews were analysed thematically using Nvivo 10.0 and three main themes emerged: (1) migrant’s experiences of food security in Tasmania; (2) the factors that influence migrant food security in Tasmania; and (3) acculturation strategies. Participants were satisfied with their current food security in Tasmania but they still encountered some challenges in the availability, accessibility and affordability of healthy and cultural food. Factors that influenced their food security were educational background, the language barrier, socioeconomic status, geographical isolation, and their cultural background. Migrants managed to adapt to the new food culture by using different acculturation strategies. Migrants residing in Tasmania encounter a diverse number of challenges pertaining to food security and use different food security strategies while acculturating to the new environment. These findings may inform other migrant communities in Australia, relevant non-government organisations and government departments and suggest strategies to address food security challenges among migrants.
International research students’ experiences in academic success
- Authors: Yeoh, Joanne , Terry, Daniel
- Date: 2013
- Type: Text , Journal article
- Relation: Universal Journal of Educational Research Vol. 1, no. 3 (2013), p. 275-280
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- Description: The flow of international students to study in Australia increases each year. It is a challenge for students to study abroad in a different sociocultural environment, especially for postgraduate research students, as they experience numerous difficulties in an unfamiliar and vastly different study environment. A study aimed to investigate the experiences of international research students and how this impacted upon their studies at the University of Tasmania (UTAS). This study also provides insight and guidance regarding the experiences of current and future international research students in Australia and universities globally. It also offers to educational services and relevant government agencies a greater understanding on how to support international research students more effectively. Qualitative research methods were used to gain deeper insights about the issue. Semi-structured interviews were conducted with ten participants who were selected randomly from different faculties within the university. All collected data were analysed by Nvivo version 10. Constructivist grounded theory was the basis of qualitative data analysis. The findings indicate that there are five main areas of difficulty when international research students are studying in the Australian tertiary education context. These are; language barrier, time management, research resources, educational background and cultural background. The findings of the study provide guidelines and references for current and prospective international research students in the Australian university context.
- Authors: Yeoh, Joanne , Terry, Daniel
- Date: 2013
- Type: Text , Journal article
- Relation: Universal Journal of Educational Research Vol. 1, no. 3 (2013), p. 275-280
- Full Text:
- Reviewed:
- Description: The flow of international students to study in Australia increases each year. It is a challenge for students to study abroad in a different sociocultural environment, especially for postgraduate research students, as they experience numerous difficulties in an unfamiliar and vastly different study environment. A study aimed to investigate the experiences of international research students and how this impacted upon their studies at the University of Tasmania (UTAS). This study also provides insight and guidance regarding the experiences of current and future international research students in Australia and universities globally. It also offers to educational services and relevant government agencies a greater understanding on how to support international research students more effectively. Qualitative research methods were used to gain deeper insights about the issue. Semi-structured interviews were conducted with ten participants who were selected randomly from different faculties within the university. All collected data were analysed by Nvivo version 10. Constructivist grounded theory was the basis of qualitative data analysis. The findings indicate that there are five main areas of difficulty when international research students are studying in the Australian tertiary education context. These are; language barrier, time management, research resources, educational background and cultural background. The findings of the study provide guidelines and references for current and prospective international research students in the Australian university context.
Challenges of food security for migrants living in a regional area of Australia : food availability, accessibility and affordability
- Yeoh, Joanne, Le, Quynh, Terry, Daniel, McManamey, Rosa
- Authors: Yeoh, Joanne , Le, Quynh , Terry, Daniel , McManamey, Rosa
- Date: 2014
- Type: Text , Journal article
- Relation: Journal of Food Security Vol. 2, no. 3 (2014), p. 72-78
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- Authors: Yeoh, Joanne , Le, Quynh , Terry, Daniel , McManamey, Rosa
- Date: 2014
- Type: Text , Journal article
- Relation: Journal of Food Security Vol. 2, no. 3 (2014), p. 72-78
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Disconnection of single-phase rooftop PVs after short-circuit faults in residential feeders
- Yengejeh, Hadi, Shahnia, Farhad, Islam, Syed
- Authors: Yengejeh, Hadi , Shahnia, Farhad , Islam, Syed
- Date: 2016
- Type: Text , Journal article
- Relation: Australian Journal of Electrical and Electronics Engineering Vol. 13, no. 2 (2016), p. 151-165
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- Description: This paper presents an analysis on the disconnection time of single-phase rooftop photovoltaic systems (PVs), located in a three-phase four-wire low voltage distribution feeder, after a single-phase and a three-phase short-circuit fault on the low-voltage feeder. The paper aims to evaluate and discuss the disconnection time and disconnection sequence of PVs in a network with 100% PV penetration level to evaluate the islanding issues that are related to the safety of people and the damage of electrical apparatus. The impact of different parameters such as the location of the fault, impedance of the fault and the ratio of PVs generation capacity to the load demand are contemplated in the analysis. Furthermore, the influence of the network earthing in the form of multiple earthed neutral and non-effectively grounded systems are evaluated on the PVs disconnection time. This research intends to figure out the conditions under which the PVs in the feeder may fail to disconnect after a single-phase or three-phase fault and continue to feed the fault.
- Authors: Yengejeh, Hadi , Shahnia, Farhad , Islam, Syed
- Date: 2016
- Type: Text , Journal article
- Relation: Australian Journal of Electrical and Electronics Engineering Vol. 13, no. 2 (2016), p. 151-165
- Full Text:
- Reviewed:
- Description: This paper presents an analysis on the disconnection time of single-phase rooftop photovoltaic systems (PVs), located in a three-phase four-wire low voltage distribution feeder, after a single-phase and a three-phase short-circuit fault on the low-voltage feeder. The paper aims to evaluate and discuss the disconnection time and disconnection sequence of PVs in a network with 100% PV penetration level to evaluate the islanding issues that are related to the safety of people and the damage of electrical apparatus. The impact of different parameters such as the location of the fault, impedance of the fault and the ratio of PVs generation capacity to the load demand are contemplated in the analysis. Furthermore, the influence of the network earthing in the form of multiple earthed neutral and non-effectively grounded systems are evaluated on the PVs disconnection time. This research intends to figure out the conditions under which the PVs in the feeder may fail to disconnect after a single-phase or three-phase fault and continue to feed the fault.
Disconnection time and sequence of rooftop PVs under short-circuit faults in low voltage networks
- Yengejeh, Hadi, Shahnia, Farhad, Islam, Syed
- Authors: Yengejeh, Hadi , Shahnia, Farhad , Islam, Syed
- Date: 2015
- Type: Text , Conference proceedings , Conference paper
- Relation: North American Power Symposium, NAPS 2015; Charlotte, United States; 4th-6th October 2015 p. 1-6
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- Description: This paper presents an analysis on the disconnection time of single-phase rooftop PVs, located in a three-phase four-wire low voltage distribution feeder after a line-to-ground short-circuit fault on the low voltage feeder. The paper aims to evaluate and discuss the disconnection time and sequence of PVs in a network with 100% PV penetration level. The impact of different parameters such as the location of the fault, impedance of the fault and the ratio of PVs generation capacity to the load demand are considered. Furthermore, the effect of the system earthing in the form of multiple earthed neutral and non-effectively grounded systems are evaluated on the PVs disconnection time. The analyses intend to figure out the conditions under which the PVs in the feeder may fail to disconnect after a line-to-ground fault and keep feeding the fault. The analyses are carried out in PSCAD/EMTDC software.
- Authors: Yengejeh, Hadi , Shahnia, Farhad , Islam, Syed
- Date: 2015
- Type: Text , Conference proceedings , Conference paper
- Relation: North American Power Symposium, NAPS 2015; Charlotte, United States; 4th-6th October 2015 p. 1-6
- Full Text:
- Reviewed:
- Description: This paper presents an analysis on the disconnection time of single-phase rooftop PVs, located in a three-phase four-wire low voltage distribution feeder after a line-to-ground short-circuit fault on the low voltage feeder. The paper aims to evaluate and discuss the disconnection time and sequence of PVs in a network with 100% PV penetration level. The impact of different parameters such as the location of the fault, impedance of the fault and the ratio of PVs generation capacity to the load demand are considered. Furthermore, the effect of the system earthing in the form of multiple earthed neutral and non-effectively grounded systems are evaluated on the PVs disconnection time. The analyses intend to figure out the conditions under which the PVs in the feeder may fail to disconnect after a line-to-ground fault and keep feeding the fault. The analyses are carried out in PSCAD/EMTDC software.
Impact of distributed rooftop photovoltaic systems on short-circuit faults in the supplying low voltage networks
- Yengejeh, Hadi, Shahnia, Farhad, Islam, Syed
- Authors: Yengejeh, Hadi , Shahnia, Farhad , Islam, Syed
- Date: 2017
- Type: Text , Journal article
- Relation: Electric Power Components and Systems Vol. 45, no. 20 (2017), p. 2257-2274
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- Description: This article evaluates the effect of randomly distributed, residential single-phase rooftop photovoltaic systems in the low voltage residential networks, during short-circuit faults on the overhead lines. The important parameters such as the fault current, the current sensed at the distribution transformer secondary, and the voltage profile along the feeder during the fault are examined. A sensitivity analysis is carried out in which the rating and location of the photovoltaic systems in the feeder, as well as the fault location and type, are the considered variables. Moreover, to demonstrate the effect of multiple photovoltaic systems with different ratings and penetration levels when distributed unequally among three phases of the network, a stochastic analysis is carried out. The article summarizes the outcomes of these two analyses to provide a better understanding of the impact of single-phase rooftop photovoltaic systems on the residential feeders during short-circuit faults.
- Authors: Yengejeh, Hadi , Shahnia, Farhad , Islam, Syed
- Date: 2017
- Type: Text , Journal article
- Relation: Electric Power Components and Systems Vol. 45, no. 20 (2017), p. 2257-2274
- Full Text:
- Reviewed:
- Description: This article evaluates the effect of randomly distributed, residential single-phase rooftop photovoltaic systems in the low voltage residential networks, during short-circuit faults on the overhead lines. The important parameters such as the fault current, the current sensed at the distribution transformer secondary, and the voltage profile along the feeder during the fault are examined. A sensitivity analysis is carried out in which the rating and location of the photovoltaic systems in the feeder, as well as the fault location and type, are the considered variables. Moreover, to demonstrate the effect of multiple photovoltaic systems with different ratings and penetration levels when distributed unequally among three phases of the network, a stochastic analysis is carried out. The article summarizes the outcomes of these two analyses to provide a better understanding of the impact of single-phase rooftop photovoltaic systems on the residential feeders during short-circuit faults.
Contributions of single–phase rooftop PVs on short circuits faults in residential feeders
- Yengejeh, Hadi, Shahnia, Farhad, Islam, Syed
- Authors: Yengejeh, Hadi , Shahnia, Farhad , Islam, Syed
- Date: 2014
- Type: Text , Conference proceedings , Conference paper
- Relation: 24th Australasian Universities Power Engineering Conference, AUPEC 2014; Perth, Australia; 28th September-1st October 2014 p. 1-6
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- Description: Sensitivity analysis results are presented to investigate the presence of single–phase rooftop Photovoltaic Cells (PV) in low voltage residential feeders, during short circuits in the overhead lines. The PV rating and location in the feeder and the fault location are considered as the variables of the sensitivity analysis. The single–phase faults are the main focus of this paper and the PV effect on fault current, current in distribution transformer secondary and the voltage at each bus of the feeder are investigated, during fault. Furthermore, to analyze the bus voltages and fault current in the presence of multiple PVs, each with different rating and location, a stochastic analysis is carried out to investigate the expected probability density function of these parameters, considering the uncertainties of PV rating and location as well as fault location.
- Authors: Yengejeh, Hadi , Shahnia, Farhad , Islam, Syed
- Date: 2014
- Type: Text , Conference proceedings , Conference paper
- Relation: 24th Australasian Universities Power Engineering Conference, AUPEC 2014; Perth, Australia; 28th September-1st October 2014 p. 1-6
- Full Text:
- Reviewed:
- Description: Sensitivity analysis results are presented to investigate the presence of single–phase rooftop Photovoltaic Cells (PV) in low voltage residential feeders, during short circuits in the overhead lines. The PV rating and location in the feeder and the fault location are considered as the variables of the sensitivity analysis. The single–phase faults are the main focus of this paper and the PV effect on fault current, current in distribution transformer secondary and the voltage at each bus of the feeder are investigated, during fault. Furthermore, to analyze the bus voltages and fault current in the presence of multiple PVs, each with different rating and location, a stochastic analysis is carried out to investigate the expected probability density function of these parameters, considering the uncertainties of PV rating and location as well as fault location.
Accounting professionalisation and occupational context: The role of the public accounting profession in China
- Authors: Yee, Helen , West, Brian
- Date: 2010
- Type: Text , Conference paper
- Relation: 6th Asia Pacific Interdisciplinary Research in Accounting Conference: Interdisciplinary Research in Accounting (APIRA 2010) p. 1-28
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- Description: While applied broadly within the setting of accounting and some other occupations, ‘profession’ is a particularly Western concept with peculiarly British origins. However, the significance of such status and the process by which it is acquired has defied precise explication. Examination of the sociology of the accounting occupation within non- Western locations can contribute to exposing and clarifying these problematic and contingent aspects of occupational stratification, as well as assist in redressing the bias towards English-speaking and European countries within the accounting history literature. Proceeding from these theoretical premises, a historical study of the accounting occupation within China is undertaken. Integrating episodes from this country into the broader historical narrative of the professionalisation of accounting reinforces – often vividly – that accountants’ work status is not bound to an innate and predetermined trajectory. Rather, the variety of localised and time-specific variables which constitute the occupational context are shown to exert a dominating influence.
- Authors: Yee, Helen , West, Brian
- Date: 2010
- Type: Text , Conference paper
- Relation: 6th Asia Pacific Interdisciplinary Research in Accounting Conference: Interdisciplinary Research in Accounting (APIRA 2010) p. 1-28
- Full Text:
- Reviewed:
- Description: While applied broadly within the setting of accounting and some other occupations, ‘profession’ is a particularly Western concept with peculiarly British origins. However, the significance of such status and the process by which it is acquired has defied precise explication. Examination of the sociology of the accounting occupation within non- Western locations can contribute to exposing and clarifying these problematic and contingent aspects of occupational stratification, as well as assist in redressing the bias towards English-speaking and European countries within the accounting history literature. Proceeding from these theoretical premises, a historical study of the accounting occupation within China is undertaken. Integrating episodes from this country into the broader historical narrative of the professionalisation of accounting reinforces – often vividly – that accountants’ work status is not bound to an innate and predetermined trajectory. Rather, the variety of localised and time-specific variables which constitute the occupational context are shown to exert a dominating influence.
Tropical cyclones and depressions over the South Pacific Ocean since the late 19th century : assessing synergistic relationship between the El Niño Southern Oscillation and Interdecadal Pacific Oscillation
- Yeasmin, Alea, Chand, Savin, Sultanova, Nargiz
- Authors: Yeasmin, Alea , Chand, Savin , Sultanova, Nargiz
- Date: 2023
- Type: Text , Journal article
- Relation: International Journal of Climatology Vol. 43, no. 12 (2023), p. 5422-5443
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- Reviewed:
- Description: Tropical cyclones (TCs) and tropical depressions (TDs), hereafter collectively referred to as tropical storms, often exhibit large year-to-year variability in the South Pacific Ocean basin. Many past studies have examined this variability in relation to the El Niño Southern Oscillation (ENSO) phenomenon, particularly using observational data from the post-satellite era (i.e., after the 1970s when TC observations became more consistent). However, less emphasis is placed on how tropical storms are modulated at interdecadal and decadal time scales such as due to Interdecadal Pacific Oscillation (IPO). This is because post-satellite data are available for relatively short time period (i.e., post-1970s), limiting our understanding of the IPO–TC relationship in the South Pacific. Here, using NOAA-CIRES 20th Century Reanalysis (20CR) dataset, we reconstruct historical records (1871–2014) of TC and depression proxies for the South Pacific Ocean basin, and then utilize these reconstructed proxies to first understand the connections between TC–ENSO and TC–IPO over the 20th century, and then investigate the combined effects of ENSO–IPO effects on TCs and depressions. Results show that La Niña (El Niño) is more dominant on TC activity than El Niño (La Niña) over the western subregion 140–170° E (eastern sub-region, 170–220° E) as expected. We also show that TC numbers are strongly modulated by the IPO phenomenon with, on average, more TCs occurring during the positive phase than during the negative phase of the IPO in both western and eastern sub-regions. We show for the first time (using a long-term reconstructed TC dataset) that the combined phases of El Niño and + IPO account for increased TC activity, as opposed to the combined phase of La Niña and
- Authors: Yeasmin, Alea , Chand, Savin , Sultanova, Nargiz
- Date: 2023
- Type: Text , Journal article
- Relation: International Journal of Climatology Vol. 43, no. 12 (2023), p. 5422-5443
- Full Text:
- Reviewed:
- Description: Tropical cyclones (TCs) and tropical depressions (TDs), hereafter collectively referred to as tropical storms, often exhibit large year-to-year variability in the South Pacific Ocean basin. Many past studies have examined this variability in relation to the El Niño Southern Oscillation (ENSO) phenomenon, particularly using observational data from the post-satellite era (i.e., after the 1970s when TC observations became more consistent). However, less emphasis is placed on how tropical storms are modulated at interdecadal and decadal time scales such as due to Interdecadal Pacific Oscillation (IPO). This is because post-satellite data are available for relatively short time period (i.e., post-1970s), limiting our understanding of the IPO–TC relationship in the South Pacific. Here, using NOAA-CIRES 20th Century Reanalysis (20CR) dataset, we reconstruct historical records (1871–2014) of TC and depression proxies for the South Pacific Ocean basin, and then utilize these reconstructed proxies to first understand the connections between TC–ENSO and TC–IPO over the 20th century, and then investigate the combined effects of ENSO–IPO effects on TCs and depressions. Results show that La Niña (El Niño) is more dominant on TC activity than El Niño (La Niña) over the western subregion 140–170° E (eastern sub-region, 170–220° E) as expected. We also show that TC numbers are strongly modulated by the IPO phenomenon with, on average, more TCs occurring during the positive phase than during the negative phase of the IPO in both western and eastern sub-regions. We show for the first time (using a long-term reconstructed TC dataset) that the combined phases of El Niño and + IPO account for increased TC activity, as opposed to the combined phase of La Niña and
Development of a long-term climatology of tropical 1 cyclones and depressions for the South Pacific 2 Ocean basin
- Authors: Yeasmin, Alea
- Date: 2023
- Type: Text , Thesis , PhD
- Full Text:
- Description: Tropical cyclones (TCs) are one of the most destructive synoptic systems that can cause enormous loss of life and property damages in the South Pacific Island nations. The impact of tropical depressions (TDs, i.e., weaker systems that do not develop into TCs) can also be staggering in the region in terms of heavy flooding and landslides, but a lack of complete records (reliable data prior to 1950) often hinders research involving TD impacts. A methodology has been developed here to detect TDs in the ERA-5 (the fifth generation European Centre for Medium-Range Weather Forecasts-ECMWF atmospheric reanalysis of the global climate) and 20CR (the Twentieth Century Reanalysis) dataset using the Okubo–Weiss–Zeta parameter (OWZP) detection scheme. The new South Pacific Enhanced Archive for Tropical Cyclones dataset (SPEArTC), the Dvorak analysis of satellite-based cloud patterns over the South Pacific Ocean basin, rainfall dataset for various stations in the South Pacific and historical archives have been utilised to validate ERA5/20CR-derived TCs and TDs. Results indicate that the OWZP method shows substantial skill in capturing the realistic climatological distribution of TCs and TDs for the South Pacific Ocean in both reanalyses dataset. The 20CR-derived TCs and TDs resemble several key characteristics of the observational records, including spatial distribution of genesis locations and track shapes. This gives us confidence that the 20CR-derived long-term records of TCs and TDs can serve as an effective tool for examining historical changes in various characteristics of TCs and TDs, particularly in the context of anthropogenic climate change. Utilizing the reconstructed proxies of TCs and TDs, their climatic connections with the El Niño Southern Oscillation (ENSO), the Interdecadal Pacific Oscillation (IPO), and the combined ENSO-IPO phases have been examined. Results show clear spatial shifts in TC activity between La Niña and El Niño phases with activity in the region 1400-1700E (1700-2200E) occurring during La Niña (El Niño) events. However, when IPO is considered synergistically with ENSO phases, we found that the combination of El Niño and the positive phase of IPO (+IPO) substantially enhances TC numbers (may be artifact influence) in both domains, noting the modulation between the two phases themselves. Similarly, La Niña and the negative phase of the IPO (-IPO) is found to enhance TC numbers in 1400-1700E. It is shown for the first time that the combined phases of El Niño and +IPO account for increased TC activity, as opposed to the combined phase of La Niña and -IPO, in the eastern sub-region. Similarly, the combined phase of La Niña and +IPO, as opposed to the combined phase of El Niño and -IPO, account for increased TC activity in the western sub-region. However, unlike TCs, the patterns of ENSO variability seem to be reversed for TDs. Changes in large-scale environmental conditions, such as environmental vertical wind shear, low-level cyclonic relative vorticity, mid-tropospheric relative humidity and sea surface temperature are linked to the various modes of variability patterns and their synergistic relationships. Results can have substantial implications, particularly on the predictability of TCs and TDs associated with the two important modes of natural variability in the South Pacific.
- Description: Doctor of Philosophy
- Authors: Yeasmin, Alea
- Date: 2023
- Type: Text , Thesis , PhD
- Full Text:
- Description: Tropical cyclones (TCs) are one of the most destructive synoptic systems that can cause enormous loss of life and property damages in the South Pacific Island nations. The impact of tropical depressions (TDs, i.e., weaker systems that do not develop into TCs) can also be staggering in the region in terms of heavy flooding and landslides, but a lack of complete records (reliable data prior to 1950) often hinders research involving TD impacts. A methodology has been developed here to detect TDs in the ERA-5 (the fifth generation European Centre for Medium-Range Weather Forecasts-ECMWF atmospheric reanalysis of the global climate) and 20CR (the Twentieth Century Reanalysis) dataset using the Okubo–Weiss–Zeta parameter (OWZP) detection scheme. The new South Pacific Enhanced Archive for Tropical Cyclones dataset (SPEArTC), the Dvorak analysis of satellite-based cloud patterns over the South Pacific Ocean basin, rainfall dataset for various stations in the South Pacific and historical archives have been utilised to validate ERA5/20CR-derived TCs and TDs. Results indicate that the OWZP method shows substantial skill in capturing the realistic climatological distribution of TCs and TDs for the South Pacific Ocean in both reanalyses dataset. The 20CR-derived TCs and TDs resemble several key characteristics of the observational records, including spatial distribution of genesis locations and track shapes. This gives us confidence that the 20CR-derived long-term records of TCs and TDs can serve as an effective tool for examining historical changes in various characteristics of TCs and TDs, particularly in the context of anthropogenic climate change. Utilizing the reconstructed proxies of TCs and TDs, their climatic connections with the El Niño Southern Oscillation (ENSO), the Interdecadal Pacific Oscillation (IPO), and the combined ENSO-IPO phases have been examined. Results show clear spatial shifts in TC activity between La Niña and El Niño phases with activity in the region 1400-1700E (1700-2200E) occurring during La Niña (El Niño) events. However, when IPO is considered synergistically with ENSO phases, we found that the combination of El Niño and the positive phase of IPO (+IPO) substantially enhances TC numbers (may be artifact influence) in both domains, noting the modulation between the two phases themselves. Similarly, La Niña and the negative phase of the IPO (-IPO) is found to enhance TC numbers in 1400-1700E. It is shown for the first time that the combined phases of El Niño and +IPO account for increased TC activity, as opposed to the combined phase of La Niña and -IPO, in the eastern sub-region. Similarly, the combined phase of La Niña and +IPO, as opposed to the combined phase of El Niño and -IPO, account for increased TC activity in the western sub-region. However, unlike TCs, the patterns of ENSO variability seem to be reversed for TDs. Changes in large-scale environmental conditions, such as environmental vertical wind shear, low-level cyclonic relative vorticity, mid-tropospheric relative humidity and sea surface temperature are linked to the various modes of variability patterns and their synergistic relationships. Results can have substantial implications, particularly on the predictability of TCs and TDs associated with the two important modes of natural variability in the South Pacific.
- Description: Doctor of Philosophy
Reconstruction of tropical cyclone and depression proxies for the South Pacific since the 1850s
- Yeasmin, Alea, Chand, Savin, Sultanova, Nargiz
- Authors: Yeasmin, Alea , Chand, Savin , Sultanova, Nargiz
- Date: 2023
- Type: Text , Journal article
- Relation: Weather and Climate Extremes Vol. 39, no. (2023), p.
- Full Text:
- Reviewed:
- Description: Southwest Pacific nations are highly vulnerable to extreme weather and climate events, particularly those associated with synoptic-scale systems such as tropical cyclones (TCs) and depressions (TDs). This study utilises the Okubo–Weiss–Zeta parameter (OWZP) method to reconstruct historical records of both TCs and TDs for the South Pacific basin using state-of-the-art NOAA-CIRES Twentieth Century Reanalysis (20CR) product. Extensive statistical assessments of these reconstructions are carried out using observational records for the satellite period (i.e., 1979–2014) as ‘ground-truths’. Results show that 20CR-derived TCs and TDs resemble several key characteristics of the observational records, including spatial distribution of genesis locations and track shapes. This gives us confidence that the 20CR-derived long-term records of TCs and TDs can serve as an effective tool for examining historical changes in various characteristics of TCs and TDs, particularly in the context of anthropogenic climate change. © 2022
- Authors: Yeasmin, Alea , Chand, Savin , Sultanova, Nargiz
- Date: 2023
- Type: Text , Journal article
- Relation: Weather and Climate Extremes Vol. 39, no. (2023), p.
- Full Text:
- Reviewed:
- Description: Southwest Pacific nations are highly vulnerable to extreme weather and climate events, particularly those associated with synoptic-scale systems such as tropical cyclones (TCs) and depressions (TDs). This study utilises the Okubo–Weiss–Zeta parameter (OWZP) method to reconstruct historical records of both TCs and TDs for the South Pacific basin using state-of-the-art NOAA-CIRES Twentieth Century Reanalysis (20CR) product. Extensive statistical assessments of these reconstructions are carried out using observational records for the satellite period (i.e., 1979–2014) as ‘ground-truths’. Results show that 20CR-derived TCs and TDs resemble several key characteristics of the observational records, including spatial distribution of genesis locations and track shapes. This gives us confidence that the 20CR-derived long-term records of TCs and TDs can serve as an effective tool for examining historical changes in various characteristics of TCs and TDs, particularly in the context of anthropogenic climate change. © 2022
Group structured reasoning for coalescing group decisions
- Yearwood, John, Stranieri, Andrew
- Authors: Yearwood, John , Stranieri, Andrew
- Date: 2009
- Type: Text , Journal article
- Relation: Group Decision and Negotiation Vol. , no. (2009), p. 1-29
- Full Text:
- Reviewed:
- Description: In this paper we present the notion of structured reasoning through a model, called the Generic/Actual Argument Model (GAAM). The model which has been used as a computational representation for machine modelling of reasoning and for hybrid combinations of human and machine reasoning can be used as a coalescent framework for decision making. Whilst the notion of structuring reasoning is not new, structured reasoning is advanced as a technique where group consensus on reasoning structures at various levels can be used to facilitate the comprehension of complex reasoning particularly where there are multiple perspectives. For an issue, the approach provides a scaffolding structure for cognitive co-operation and a normative reasoning structure against which group participants can identify points of difference and points in common as well as the nature of the differences and similarities. Intra-group transparency characterized by the ability to recognise points in common and understand the nature of differences is important to the process of coalescing group decisions that carry maximum group support. © 2009 Springer Science+Business Media B.V.
- Authors: Yearwood, John , Stranieri, Andrew
- Date: 2009
- Type: Text , Journal article
- Relation: Group Decision and Negotiation Vol. , no. (2009), p. 1-29
- Full Text:
- Reviewed:
- Description: In this paper we present the notion of structured reasoning through a model, called the Generic/Actual Argument Model (GAAM). The model which has been used as a computational representation for machine modelling of reasoning and for hybrid combinations of human and machine reasoning can be used as a coalescent framework for decision making. Whilst the notion of structuring reasoning is not new, structured reasoning is advanced as a technique where group consensus on reasoning structures at various levels can be used to facilitate the comprehension of complex reasoning particularly where there are multiple perspectives. For an issue, the approach provides a scaffolding structure for cognitive co-operation and a normative reasoning structure against which group participants can identify points of difference and points in common as well as the nature of the differences and similarities. Intra-group transparency characterized by the ability to recognise points in common and understand the nature of differences is important to the process of coalescing group decisions that carry maximum group support. © 2009 Springer Science+Business Media B.V.
Experimental investigation of three machine learning algorithms for ITS dataset
- Yearwood, John, Kang, Byeongho, Kelarev, Andrei
- Authors: Yearwood, John , Kang, Byeongho , Kelarev, Andrei
- Date: 2009
- Type: Text , Conference paper
- Relation: Paper presented at First International Conference, FGIT 2009, Future Generation Information Technology, Jeju Island, Korea : 10th-12th December 2009 Vol. 5899, p. 308-316
- Full Text:
- Description: The present article is devoted to experimental investigation of the performance of three machine learning algorithms for ITS dataset in their ability to achieve agreement with classes published in the biologi cal literature before. The ITS dataset consists of nuclear ribosomal DNA sequences, where rather sophisticated alignment scores have to be used as a measure of distance. These scores do not form a Minkowski metric and the sequences cannot be regarded as points in a finite dimensional space. This is why it is necessary to develop novel machine learning ap proaches to the analysis of datasets of this sort. This paper introduces a k-committees classifier and compares it with the discrete k-means and Nearest Neighbour classifiers. It turns out that all three machine learning algorithms are efficient and can be used to automate future biologically significant classifications for datasets of this kind. A simplified version of a synthetic dataset, where the k-committees classifier outperforms k-means and Nearest Neighbour classifiers, is also presented.
- Description: 2003007844
- Authors: Yearwood, John , Kang, Byeongho , Kelarev, Andrei
- Date: 2009
- Type: Text , Conference paper
- Relation: Paper presented at First International Conference, FGIT 2009, Future Generation Information Technology, Jeju Island, Korea : 10th-12th December 2009 Vol. 5899, p. 308-316
- Full Text:
- Description: The present article is devoted to experimental investigation of the performance of three machine learning algorithms for ITS dataset in their ability to achieve agreement with classes published in the biologi cal literature before. The ITS dataset consists of nuclear ribosomal DNA sequences, where rather sophisticated alignment scores have to be used as a measure of distance. These scores do not form a Minkowski metric and the sequences cannot be regarded as points in a finite dimensional space. This is why it is necessary to develop novel machine learning ap proaches to the analysis of datasets of this sort. This paper introduces a k-committees classifier and compares it with the discrete k-means and Nearest Neighbour classifiers. It turns out that all three machine learning algorithms are efficient and can be used to automate future biologically significant classifications for datasets of this kind. A simplified version of a synthetic dataset, where the k-committees classifier outperforms k-means and Nearest Neighbour classifiers, is also presented.
- Description: 2003007844
Generic arguments : A framework for supporting online deliberative discourse
- Yearwood, John, Stranieri, Andrew
- Authors: Yearwood, John , Stranieri, Andrew
- Date: 2002
- Type: Text , Conference paper
- Relation: Paper presented at the Thirteenth Australasian Conference on Information Systems, Melbourne : 4th December, 2002
- Full Text:
- Reviewed:
- Description: In this paper we propose a framework based on argumentation that can be used to support deliberative discourse on line. Online communities have several distinct advantages as very open forums but they also have some deep disadvantages. We argue that the proposed framework and web application GAAMtalk permits and encourages the positive elements of online deliberation that will enhance discussions.
- Description: E1
- Description: 2003000114
- Authors: Yearwood, John , Stranieri, Andrew
- Date: 2002
- Type: Text , Conference paper
- Relation: Paper presented at the Thirteenth Australasian Conference on Information Systems, Melbourne : 4th December, 2002
- Full Text:
- Reviewed:
- Description: In this paper we propose a framework based on argumentation that can be used to support deliberative discourse on line. Online communities have several distinct advantages as very open forums but they also have some deep disadvantages. We argue that the proposed framework and web application GAAMtalk permits and encourages the positive elements of online deliberation that will enhance discussions.
- Description: E1
- Description: 2003000114
Profiling phishing emails based on hyperlink information
- Yearwood, John, Mammadov, Musa, Banerjee, Arunava
- Authors: Yearwood, John , Mammadov, Musa , Banerjee, Arunava
- Date: 2010
- Type: Text , Conference paper
- Relation: Paper presented at 2010 International Conference on Advances in Social Network Analysis and Mining, ASONAM 2010, Odense : 9th-11th August 2010 p. 120-127
- Full Text:
- Description: In this paper, a novel method for profiling phishing activity from an analysis of phishing emails is proposed. Profiling is useful in determining the activity of an individual or a particular group of phishers. Work in the area of phishing is usually aimed at detection of phishing emails. In this paper, we concentrate on profiling as distinct from detection of phishing emails. We formulate the profiling problem as a multi-label classification problem using the hyperlinks in the phishing emails as features and structural properties of emails along with whois (i.e.DNS) information on hyperlinks as profile classes. Further, we generate profiles based on classifier predictions. Thus, classes become elements of profiles. We employ a boosting algorithm (AdaBoost) as well as SVM to generate multi-label class predictions on three different datasets created from hyperlink information in phishing emails. These predictions are further utilized to generate complete profiles of these emails. Results show that profiling can be done with quite high accuracy using hyperlink information. © 2010 Crown Copyright.
- Authors: Yearwood, John , Mammadov, Musa , Banerjee, Arunava
- Date: 2010
- Type: Text , Conference paper
- Relation: Paper presented at 2010 International Conference on Advances in Social Network Analysis and Mining, ASONAM 2010, Odense : 9th-11th August 2010 p. 120-127
- Full Text:
- Description: In this paper, a novel method for profiling phishing activity from an analysis of phishing emails is proposed. Profiling is useful in determining the activity of an individual or a particular group of phishers. Work in the area of phishing is usually aimed at detection of phishing emails. In this paper, we concentrate on profiling as distinct from detection of phishing emails. We formulate the profiling problem as a multi-label classification problem using the hyperlinks in the phishing emails as features and structural properties of emails along with whois (i.e.DNS) information on hyperlinks as profile classes. Further, we generate profiles based on classifier predictions. Thus, classes become elements of profiles. We employ a boosting algorithm (AdaBoost) as well as SVM to generate multi-label class predictions on three different datasets created from hyperlink information in phishing emails. These predictions are further utilized to generate complete profiles of these emails. Results show that profiling can be done with quite high accuracy using hyperlink information. © 2010 Crown Copyright.
A web-based Narrative construction environment
- Yearwood, John, Stranieri, Andrew, Osman, Deanna
- Authors: Yearwood, John , Stranieri, Andrew , Osman, Deanna
- Date: 2008
- Type: Text , Conference paper
- Relation: Paper presented at NILE 2008: 5th International Conference on Narrative and Interactive Learning Environments, Edinburgh, Scotland : 6th-8th August 2008 p. 78-81
- Full Text:
- Description: This paper describes a web-based environment for constructing narrative from story snippets contributed by a community of interest. The underlying model uses an argument based structure to infer the next event in the narrative sequence. The approach makes use of both events and higher level story elements derived from Polti’s dramatic situations. Dramatic situations used are consistent with a theme, and events are generally constrained by the dramatic situation. The narrative generated is a function of the event history, the dramatic situations chosen and the plausible inferences about next events that are contributed by a community of interest in the theme. At this stage, a player’s actions are simulated using a random selection from a set and the implementation of a nonsense filter. Example outputs from the system are provided and discussed.
- Description: 2003006499
- Authors: Yearwood, John , Stranieri, Andrew , Osman, Deanna
- Date: 2008
- Type: Text , Conference paper
- Relation: Paper presented at NILE 2008: 5th International Conference on Narrative and Interactive Learning Environments, Edinburgh, Scotland : 6th-8th August 2008 p. 78-81
- Full Text:
- Description: This paper describes a web-based environment for constructing narrative from story snippets contributed by a community of interest. The underlying model uses an argument based structure to infer the next event in the narrative sequence. The approach makes use of both events and higher level story elements derived from Polti’s dramatic situations. Dramatic situations used are consistent with a theme, and events are generally constrained by the dramatic situation. The narrative generated is a function of the event history, the dramatic situations chosen and the plausible inferences about next events that are contributed by a community of interest in the theme. At this stage, a player’s actions are simulated using a random selection from a set and the implementation of a nonsense filter. Example outputs from the system are provided and discussed.
- Description: 2003006499
Narrative-based interactive learning environments from modelling reasoning
- Yearwood, John, Stranieri, Andrew
- Authors: Yearwood, John , Stranieri, Andrew
- Date: 2007
- Type: Text , Journal article
- Relation: Educational Technology and Society Vol. 10, no. 3 (2007), p. 192-208
- Full Text:
- Reviewed:
- Description: Narrative and story telling has a long history of use in structuring, organising and communicating human experience. This paper describes a narrative based interactive intelligent learning environment which aims to elucidate practical reasoning using interactive emergent narratives that can be used in training novices in decision making. Its design is based on an approach to generating narrative from knowledge that has been modelled in specific decision/reasoning domains. The approach uses a narrative model that is guided partially by inference and contextual information contained in the particular knowledge representation used, the Generic/Actual argument model of structured reasoning. The approach is described with examples in the area of critical care nursing training and positive learning outcomes are reported. © International Forum of Educational Technology & Society (IFETS).
- Description: C1
- Description: 2003002522
- Authors: Yearwood, John , Stranieri, Andrew
- Date: 2007
- Type: Text , Journal article
- Relation: Educational Technology and Society Vol. 10, no. 3 (2007), p. 192-208
- Full Text:
- Reviewed:
- Description: Narrative and story telling has a long history of use in structuring, organising and communicating human experience. This paper describes a narrative based interactive intelligent learning environment which aims to elucidate practical reasoning using interactive emergent narratives that can be used in training novices in decision making. Its design is based on an approach to generating narrative from knowledge that has been modelled in specific decision/reasoning domains. The approach uses a narrative model that is guided partially by inference and contextual information contained in the particular knowledge representation used, the Generic/Actual argument model of structured reasoning. The approach is described with examples in the area of critical care nursing training and positive learning outcomes are reported. © International Forum of Educational Technology & Society (IFETS).
- Description: C1
- Description: 2003002522
Applying Turner's three-process theory of power to the study of power relations in a troubled information systems implementation
- Ye, Michelle, de Salas, Kristy, Ollington, Nadia, McKay, Judy
- Authors: Ye, Michelle , de Salas, Kristy , Ollington, Nadia , McKay, Judy
- Date: 2017
- Type: Text , Journal article
- Relation: Australasian Journal of Information Systems Vol. 21, no. (2017), p. 1-25
- Full Text:
- Reviewed:
- Description: This paper explores the nature and exercise of power in an interpretive case study of a troubled information systems (IS) implementation in a university in the Asia Pacific region using Turner's Three-Process Theory of Power based on Social Identity Theory and Self-Categorisation Theory. The findings demonstrate the value of Turner's theoretical lens as well as its insufficiency for explaining all power related activities. This research has led to the development of an extended Three-Process Theory of Power by adding the alternative components that emerged from the data in the case study in relation to the nature and exercises of power. Based on the findings, we further recommend specific guidelines for IS theoreticians and practitioners including advice to project managers on a range of key issues. Thus, this paper contributes theorising the sources of power and tactical applications of power in given situations, particularly in IS implementation projects. © 2017 Ye, de Salas, Ollington & McKay.
- Authors: Ye, Michelle , de Salas, Kristy , Ollington, Nadia , McKay, Judy
- Date: 2017
- Type: Text , Journal article
- Relation: Australasian Journal of Information Systems Vol. 21, no. (2017), p. 1-25
- Full Text:
- Reviewed:
- Description: This paper explores the nature and exercise of power in an interpretive case study of a troubled information systems (IS) implementation in a university in the Asia Pacific region using Turner's Three-Process Theory of Power based on Social Identity Theory and Self-Categorisation Theory. The findings demonstrate the value of Turner's theoretical lens as well as its insufficiency for explaining all power related activities. This research has led to the development of an extended Three-Process Theory of Power by adding the alternative components that emerged from the data in the case study in relation to the nature and exercises of power. Based on the findings, we further recommend specific guidelines for IS theoreticians and practitioners including advice to project managers on a range of key issues. Thus, this paper contributes theorising the sources of power and tactical applications of power in given situations, particularly in IS implementation projects. © 2017 Ye, de Salas, Ollington & McKay.
An empirical analysis of sediment export dynamics from a constructed landform in the wet tropics
- Yavari, Shahla, McIntyre, Neil, Baumgartl, Thomas
- Authors: Yavari, Shahla , McIntyre, Neil , Baumgartl, Thomas
- Date: 2021
- Type: Text , Journal article
- Relation: Water (Switzerland) Vol. 13, no. 8 (2021), p.
- Full Text:
- Reviewed:
- Description: Although plot-scale erosion experiments are numerous, there are few studies on constructed landforms. This limits the understanding of their long-term stability, which is especially important for planning mined land rehabilitation. The objective of this study was to gain insight into the erosion processes in a 30 × 30 m trial plot on a mine waste rock dump in tropical northern Australia. The relationships between rainfall, runoff and suspended and bedload sediment export were assessed at annual, seasonal, inter-event and intra-event timescales. During a five-year study period, 231 rainfall– runoff–sediment export events were examined. The measured bedload and suspended sediments (mainly represented in nephelometric turbidity units (NTU)) showed the dominance of the wet season and heavy rainfall events. The bedload dominated the total mass, although the annual bedload diminished by approximately 75% over the five years, with greater flow energy required over time to mobilise the same bedload. The suspended load was more sustained, though it also exhibited an exhaustion process, with equal rainfall and runoff volumes and intensities, leading to lower NTU values over time. Intra-event NTU dynamics, including runoff-NTU time lags and hysteretic behaviours, were somewhat random from one event to the next, indicating the influence of the antecedent distribution of mobilisable sediments. The value of the results for supporting predictive modelling is discussed. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
- Authors: Yavari, Shahla , McIntyre, Neil , Baumgartl, Thomas
- Date: 2021
- Type: Text , Journal article
- Relation: Water (Switzerland) Vol. 13, no. 8 (2021), p.
- Full Text:
- Reviewed:
- Description: Although plot-scale erosion experiments are numerous, there are few studies on constructed landforms. This limits the understanding of their long-term stability, which is especially important for planning mined land rehabilitation. The objective of this study was to gain insight into the erosion processes in a 30 × 30 m trial plot on a mine waste rock dump in tropical northern Australia. The relationships between rainfall, runoff and suspended and bedload sediment export were assessed at annual, seasonal, inter-event and intra-event timescales. During a five-year study period, 231 rainfall– runoff–sediment export events were examined. The measured bedload and suspended sediments (mainly represented in nephelometric turbidity units (NTU)) showed the dominance of the wet season and heavy rainfall events. The bedload dominated the total mass, although the annual bedload diminished by approximately 75% over the five years, with greater flow energy required over time to mobilise the same bedload. The suspended load was more sustained, though it also exhibited an exhaustion process, with equal rainfall and runoff volumes and intensities, leading to lower NTU values over time. Intra-event NTU dynamics, including runoff-NTU time lags and hysteretic behaviours, were somewhat random from one event to the next, indicating the influence of the antecedent distribution of mobilisable sediments. The value of the results for supporting predictive modelling is discussed. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.