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Wilfrid Laurier University

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Utilization Of The Yamamoto Cyclotrimerization Reaction Towards The Synthesis Of Polycyclic Aromatic Compounds, Josh Ledrew Jan 2022

Utilization Of The Yamamoto Cyclotrimerization Reaction Towards The Synthesis Of Polycyclic Aromatic Compounds, Josh Ledrew

Theses and Dissertations (Comprehensive)

The overall theme of this research was to synthesize and study the structure-property relationships of novel polycyclic aromatic compounds capable of self-assembling to form liquid crystalline, and microporous structures, as well as molecules capable of molecular recognition. The unifying theme that connects this research is the utilization of the Yamamoto coupling reaction to access the desired polycyclic aromatic hydrocarbon targets. More specifically, the scope of the Yamamoto coupling reaction was explored for the synthesis of electron-deficient triphenylene derivatives that are otherwise difficult to prepare. The molecules prepared via the Yamamoto coupling reaction are expected to be further utilized as intermediates …


Changes In Lake Drainage In The Western Canadian Arctic, Dilshan Kariyawasam, Philip Marsh Dr Jan 2022

Changes In Lake Drainage In The Western Canadian Arctic, Dilshan Kariyawasam, Philip Marsh Dr

Theses and Dissertations (Comprehensive)

Nearly half of all Pan-Arctic lakes are situated in the Canadian Arctic, with many of these lakes being of thermokarst origin. Thermokarst lakes are sensitive to changes in the surrounding environment, making them useful indicators to examine the condition of hydrological systems in response to rapid climate warming, a trend which has been well observed in the Canadian Western Arctic. In this study, we use aerial photography to quantify lake area and count changes for lakes in the Inuvik-Tuktoyaktuk region, between 1950 and 2004. A combination of aerial photography and Landsat imagery were used in identifying drained thermokarst lake basins …


Enhancing Zero-Shot And Few-Shot Text Classification Using Pre-Trained Language Models, Yanan Chen Jan 2022

Enhancing Zero-Shot And Few-Shot Text Classification Using Pre-Trained Language Models, Yanan Chen

Theses and Dissertations (Comprehensive)

In recent years, the community of natural language processing (NLP) has seen amazing progress in the development of pre-trained language models (PLMs). The novel paradigm of PLMs does not require labeled data, allowing us to experiment with increased training scale through employing freely available colossal online self-training corpus to push the limits. Language models (LMs), such as GPT, BERT and T5, have achieved high performance on a wide range of NLP tasks. Meanwhile, research on zero-shot and few-shot text classification has received increasing attention. As labelling can be costly and time-consuming, how to perform data augmentation (DA) and enhance the …


Exploring Visitor Perceptions And Behaviours Related To Ticks And Lyme Disease Risk In An Ontario Protected Area, Ryan Brady Jan 2022

Exploring Visitor Perceptions And Behaviours Related To Ticks And Lyme Disease Risk In An Ontario Protected Area, Ryan Brady

Theses and Dissertations (Comprehensive)

Lyme disease is the most common vector-borne zoonosis in North America and over the past decade, reported cases of the disease have been rapidly increasing in many regions throughout Canada. The relative novelty of this public health threat presents nature-based tourism and recreation organizations with a range of policy and management challenges. Currently, there is a limited understanding of public perceptions and behaviours associated with tick and Lyme disease risk, especially within a Canadian parks and protected areas visitation and visitor experience context. To address this practical and scholarly knowledge gap, this study utilized in-situ surveys to explore visitor perceptions, …


Air Quality: Assessment Of Pollutant Levels And Chemistry In Kitchener, On Using Multisensor Pods, Wisam Mohammed Jan 2022

Air Quality: Assessment Of Pollutant Levels And Chemistry In Kitchener, On Using Multisensor Pods, Wisam Mohammed

Theses and Dissertations (Comprehensive)

Air quality is a growing concern amongst governmental bodies worldwide. A large number of scientific studies accumulated over the past 25 years suggest that poor ambient air quality is attributed to adverse health effects, especially in vulnerable communities that exhibit pre-existing conditions. The United Nations Children’s Fund (UNICEF) reported around 600 000 deaths globally in children under the age of 5 as a result of acute lower respiratory infections caused by poor air quality. With the current statistics on air quality impacts, it is clear that more needs to be done. This MSc work aims to put into perspective the …


Implementing Connectivity Conservation In Canada, Christopher J. Lemieux, Aerin L. Jacob, Paul A. Gray Jan 2021

Implementing Connectivity Conservation In Canada, Christopher J. Lemieux, Aerin L. Jacob, Paul A. Gray

Geography and Environmental Studies Faculty Publications

No abstract provided.


Modeling Multivariate Hopfield-Transformer Hawkes Process: Application To Sovereign Credit Default Swaps, Mohsen Bahremani Jan 2021

Modeling Multivariate Hopfield-Transformer Hawkes Process: Application To Sovereign Credit Default Swaps, Mohsen Bahremani

Theses and Dissertations (Comprehensive)

Hawkes process was evolved so that the past events contribute to the occurrence time of future events by self-exciting or mutually exciting. However, many real-world data do not follow the Hawkes process's assumptions (i.e., positivity, additivity, and exponential decay) and become more complex to be modeled by the traditional Hawkes processes, so the neural Hawkes process was developed to tackle the challenges. However, Recurrent Neural Networks (RNN) fail to capture long-term dependencies among multiple point processes, and Transformer Hawkes processes only address temporal characteristics of Hawkes processes. In this thesis, we proposed a combination of neural networks and Hawkes processes …


Change Detection And Landscape Similarity Comparison Using Computer Vision Methods, Karim Malik Wilfrid Laurier University Jan 2021

Change Detection And Landscape Similarity Comparison Using Computer Vision Methods, Karim Malik Wilfrid Laurier University

Theses and Dissertations (Comprehensive)

Human-induced disturbances of terrestrial and aquatic ecosystems continue at alarming rates. With the advent of both raw sensor and analysis-ready datasets, the need to monitor ecosystem disturbances is now more imperative than ever; yet the task is becoming increasingly complex with increasing sources and varieties of earth observation data. In this research, computer vision methods and tools are interrogated to understand their capability for comparing spatial patterns. A critical survey of literature provides evidence that computer vision methods are relatively robust to scale and highlights issues involved in parameterization of computer vision models for characterizing significant pattern information in a …


Binary Black Widow Optimization Algorithm For Feature Selection Problems, Ahmed Al-Saedi Jan 2021

Binary Black Widow Optimization Algorithm For Feature Selection Problems, Ahmed Al-Saedi

Theses and Dissertations (Comprehensive)

This thesis addresses feature selection (FS) problems, which is a primary stage in data mining. FS is a significant pre-processing stage to enhance the performance of the process with regards to computation cost and accuracy to offer a better comprehension of stored data by removing the unnecessary and irrelevant features from the basic dataset. However, because of the size of the problem, FS is known to be very challenging and has been classified as an NP-hard problem. Traditional methods can only be used to solve small problems. Therefore, metaheuristic algorithms (MAs) are becoming powerful methods for addressing the FS problems. …


Strategies For Reducing Greenhouse Gases From Liquid Dairy Manure, Vera Sokolov Jan 2021

Strategies For Reducing Greenhouse Gases From Liquid Dairy Manure, Vera Sokolov

Theses and Dissertations (Comprehensive)

Livestock production, including the storage, handling, and spreading of manure, are among the largest contributors to greenhouse gas emissions from the agricultural sector. Liquid dairy manure storages are hot spots of methane (CH4), nitrous oxide (N2O) and ammonia (NH3). Both CH4 and N2O are greenhouse gases (GHG) which contribute to global warming, while NH3 is an indirect source of N2O and a risk to human health. Reducing emissions from manure storages is important not only for protection of environment and humans, but also for conserving the nutrients in …


Self-Exciting Point Process For Modelling Terror Attack Data, Siyi Wang Jan 2021

Self-Exciting Point Process For Modelling Terror Attack Data, Siyi Wang

Theses and Dissertations (Comprehensive)

Terrorism becomes more rampant in recent years because of separatism and extreme nationalism, which brings a serious threat to the national security of many countries in the world. The analysis of spatial and temporal patterns of terror data is significant in containing terrorism. This thesis focuses on building and applying a temporal point process called self-exciting point process to fit the terror data from 1970 to 2018 of 10 countries. The data come from the Global Terrorism database. Further, an application in predicting the number of terror events based on the self-exciting model is another main innovative idea, in which …


The Potential For Remote Sensing Measurement Of Dissolved Organic Carbon As A Tool For Metal Risk Assessments, Mickey Nielsen Jan 2021

The Potential For Remote Sensing Measurement Of Dissolved Organic Carbon As A Tool For Metal Risk Assessments, Mickey Nielsen

Theses and Dissertations (Comprehensive)

The biotic ligand model (BLM) is a tool used to quantitatively evaluate how receiving water chemistry affects the bioavailability of metals. Sensitivity testing can be used to understand how the model outputs vary in response to systematic changes in water chemistry inputs. This will allow users of such models to understand how accurate their input parameters must be for a specified level of confidence in the output. Our focus was on dissolved organic carbon (DOC), which is often the most limiting data for application of BLM approaches to metals risk management. To potentially address DOC data limitations remote sensing can …


A Model For Massless Gravitons In Radiation And Matter Dominated Universes, Ioannis Haranas, Eli Cavan, Ioannis Gkigkitzis Nov 2020

A Model For Massless Gravitons In Radiation And Matter Dominated Universes, Ioannis Haranas, Eli Cavan, Ioannis Gkigkitzis

Physics and Computer Science Faculty Publications

A massless model of the graviton is explored by considering the minimum amount of information they can carry. The total entropy of the universe is calculated and compared to estimates from Super Massive Black holes and massive models of the graviton. The running cosmological constant is calculated using the entropy relation previously computed and compared to its experimentally accepted value. Both results are quantified considering radiation and matter dominated universes.


Modified Newtonian Dynamics Effects In A Region Dominated By Dark Matter And A Cosmological Constant Λ, Ioannis Haranas, Kristin Cobbett, Ioannis Gkigkitzis, Athanasios Alexiou, Eli Cavan Oct 2020

Modified Newtonian Dynamics Effects In A Region Dominated By Dark Matter And A Cosmological Constant Λ, Ioannis Haranas, Kristin Cobbett, Ioannis Gkigkitzis, Athanasios Alexiou, Eli Cavan

Physics and Computer Science Faculty Publications

We study the motion of a secondary celestial body under the influence of a corrected gravitational potential in a modified Newtonian dynamics scenario. Furthermore we look within the Milky-way where the first correction to the potential results from a modified Poisson equation, and includes two mew terms one of which is of the form ln(r/rmax) and the other is associated with the cosmological constant lambda L added to the Newtonian potential. The regions of influence of the two potentials are associated with regions of interested bounded by the conditions for the Newtonian potential, the logarithmic …


Fetishized Nature Or Life-Giving Breath? Religion As Skill In Climate Change, Sigurd Bergmann May 2020

Fetishized Nature Or Life-Giving Breath? Religion As Skill In Climate Change, Sigurd Bergmann

Consensus

Anthropogenic climate change and unsustainable modes of production, consumption and lifestyles represent one of the most demanding challenges facing Earth, our home and humanity. Therefore religious belief, faith communities and spiritual commitment are highly needed to prepare the ground for what has been described as the necessary “great transformation”. To achieve this transformation, we need a new climate narrative and iconography, supported by a broad alliance of local and trans-local social forces. Religion has a significant role to play in this mobilization. This article begins by depicting several reasons that religion is a crucial driving force in the needed great …


Ecology And Christian Education: How Sustainability Discourse And Theological Anthropology Inform Teaching Methods, Chad Rimmer May 2020

Ecology And Christian Education: How Sustainability Discourse And Theological Anthropology Inform Teaching Methods, Chad Rimmer

Consensus

This paper will sketch theoretical synergies between sustainability discourse and a Christian ecotheological approach to religious education, and point to pedagogical possibilities for bridging the two disciplines. Theology and natural science operate with certain anthropological assumptions. Those underlying anthropologies inform the teaching methods of environmental and religious education. Anthropologies that conceive of human being outside of ecological relationships are a root problem of our current ecological crisis. Many economic, political and social discourses colonize people from the land, particularly children, exacerbating the root causes of sustainability. This paper affirms that linking sustainability discourse and religious education is a way to …


Women, Climate Change And Eco-Theology, Mary (Joy) Philip May 2020

Women, Climate Change And Eco-Theology, Mary (Joy) Philip

Consensus

The impact of climate change is not proportionate to the ones that contribute to it. It is the world’s poorest and those in vulnerable situations, especially women and children, who bear the brunt of environmental, economic and social shocks. This paper highlights the fact that women are disproportionately affected by climate change, when they are primarily the ones that have been caring for and preserving the earth. This paper also argues for the need for eco-consciousness and the increased participation of women in climate initiatives, as women have a theology and spirituality undergirded by eco-consciousness.


Sustainability And Climate In Religion: A Case Of Study Of The Green Churches Network In Africa (Toile Des Églises Vertes En Afrique) Teva, Marcel Ngirinshuti May 2020

Sustainability And Climate In Religion: A Case Of Study Of The Green Churches Network In Africa (Toile Des Églises Vertes En Afrique) Teva, Marcel Ngirinshuti

Consensus

Faced with the ecological crisis, many churches are involved in the search for concrete solutions. Since 2016, the Green Churches Network in Africa (TEVA), a network of churches, denominational structures and associations, which are committed to caring for the "common home" (planet-earth) in Africa. This organization currently has (as of 2019) 1,808 parishes grouped into 19 churches in 12 African countries. The vision of TEVA is to reach 2020 green parishes by the end of 2020. Starting with the fact that ecological questions are often perceived as utopian and very complex, TEVA aims to promote knowledge of African ecological issues …


Sustainability And Religion, Chad Rimmer, Mary (Joy) Philip May 2020

Sustainability And Religion, Chad Rimmer, Mary (Joy) Philip

Consensus

No abstract provided.


Introducing A Comparative Ecotheology: Islamic Concept Of Basmalah And Luther’S Commentary On The Ten Commandments, Sayed Hassan Akhlaq May 2020

Introducing A Comparative Ecotheology: Islamic Concept Of Basmalah And Luther’S Commentary On The Ten Commandments, Sayed Hassan Akhlaq

Consensus

In our trying time of the COVID-19 pandemic, this paper discusses current environmental concerns in light of critical questions about the relationship between God and Mother Earth. This paper addresses this question in an inter-religious context. In order to fulfil its original duty of inculcating spirituality, faith can build a bridge between God and people on a constructive understanding of the Earth. To this end, Christianity and Islam offer notions of divine grace and divine lutf to do this duty. In this paper, I examine two inspiring sources: the Islamic motto of Basmalah, and Luther’s commentary on the Ten Commandments …


Religious Environmental Stewardship, The Sabbath And Sustainable Futures In Africa: Implications For Sustainability Discourse, Ben-Willie Kwaku Golo May 2020

Religious Environmental Stewardship, The Sabbath And Sustainable Futures In Africa: Implications For Sustainability Discourse, Ben-Willie Kwaku Golo

Consensus

In terms of goals and approaches, the potentials of religion and faith communities have had a prolonged marginalisation from the rather intense academic and political engagements in the suitability discourse with a consensus on the concept of sustainability as both an approach and a goal. In this paper, I argue that the highly religious African context would require a religiously inspired and phrased recourse towards a comprehensive sustainability, rather than a solely secular concept of environmental sustainability. This is much more so when environmental sustainability is largely a secular vision of a religious one – environmental stewardship. Ignoring the beliefs, …


Adam, Dust Of The Earth: A Paradise Received And Incomplete In The Biblical Accounts Of Creation. Some Philological Observations On The Creation Accounts, Jean Koulagna May 2020

Adam, Dust Of The Earth: A Paradise Received And Incomplete In The Biblical Accounts Of Creation. Some Philological Observations On The Creation Accounts, Jean Koulagna

Consensus

In Christian thinking about climate and environment issues, Dogmatic theology has often seemed to precede the exegesis of biblical texts. And when it is suggested, this exegesis is usually based on previously formulated theological conclusions. In other words, exegesis is there to support ethical stands that are no doubt laudable, but have been already established. Under these conditions, it becomes difficult to analyze those texts as they are and to understand them within the historical and anthropological contexts in which they were produced. This article attempts to break this trend by suggesting philological observations concerning the creation accounts in Genesis. …


When Environmental Obligations Collide With State Sovereignty: An International And Sharia Law Perspective, Seyed Masoud Noori, Soheila Ebrahimi Louyeh May 2020

When Environmental Obligations Collide With State Sovereignty: An International And Sharia Law Perspective, Seyed Masoud Noori, Soheila Ebrahimi Louyeh

Consensus

This article critically reviews the notion of State sovereignty under international law and argues that to achieve eco-justice as well as sustainable development goals, a restrictive and ecological approach needs to be taken toward the principle of states’ permanent sovereignty over natural resources. Environmental sustainability requires states’ environmental obligations to be identified as erga omnes so they can be addressed toward the international community as a whole and fall within the scope of article 48 of the ILC Articles on States Responsibility. Interestingly, in complete alignment with this progressive interpretation, sustainable utilization of natural resources has a longstanding foundation in …


Towards A Green Diapraxis: Experiences And Reflections From An Interfaith Journey, Einar Tjelle May 2020

Towards A Green Diapraxis: Experiences And Reflections From An Interfaith Journey, Einar Tjelle

Consensus

The article explores the increased cooperation and dynamic learning between religions during the last decades, on the themes of climate, environment and sustanability. Examples are given from a Norwegian interfaith context, but with global links as well. This cooperation has broadened the scope and perspectives of churches and religions. Contextual and holistic approaches have emerged as fruits of this mutual learning and exchange, the author claims. Pope Francis` encyclical Laudato Si` has captured important parts of this development with its strong message of interconnectedness and moral responsibility. It has also stimulated a wider religious and interfaith global commitment to Mother …


From Environmental Activism To Environmental Education A Historical Overview, Evaluations And A Suggestion For A Path Forward For The Religious Institutions As Partners For A Global Green Shift, Tom Sverre Tomren May 2020

From Environmental Activism To Environmental Education A Historical Overview, Evaluations And A Suggestion For A Path Forward For The Religious Institutions As Partners For A Global Green Shift, Tom Sverre Tomren

Consensus

In this article, the author shows how all the major world religions have engaged in climate and environmental activism by developing theology and practical projects for more than fifty years. Using metadata from the European Social Survey, he shows that members of all religious traditions in Europe have become increasingly positive to the environment and nature. Especially noticeable is the increased engagement of Protestant Christians. Tomren uses a case study from the Lutheran Church in Norway to show how religious actors have a great influence on their own members. Against this background, the author argues that religious institutions should see …


Rockhounding, Seafaring, And Other Material Tales For The End Of The World, Noemie Fortin Mar 2020

Rockhounding, Seafaring, And Other Material Tales For The End Of The World, Noemie Fortin

The Goose

In the face of accelerated environmental degradation and climate instability, the future of the Earth and of all life on earth is difficult to visualize. Therefore, the different mediums through which we consider environmental issues are just as important as the actions we take to address them. Focusing on three projects combining art, science, and activism, this article suggests a compilation of material tales. They tell stories of plastic rocks and aluminum nuggets where the protagonists are partly finely crafted objects, partly waste materials, and sometimes both at once. Artists Kelly Jazvac, Yesenia Thibeault-Picazo, and the collective Studio Swine collaborate …


Dynamics And Stability Of The Two Body Problem With Yukawa Correction, Eli Cavan, Ioannis Haranas, Ioannis Gkigkitzis Jan 2020

Dynamics And Stability Of The Two Body Problem With Yukawa Correction, Eli Cavan, Ioannis Haranas, Ioannis Gkigkitzis

Physics and Computer Science Faculty Publications

We explore the dynamics and stability of the two body problem by modifying the Newtonian potential with the Yukawa potential. This model may be considered a theory of modified gravity; where the interaction is not simply the kepler solution for large distance. The stability is investigated by deriving the Jacobian of the linearized matrix equation and evaluating the eigenvalues of the various equilibrium points calculated during the analysis. The subcases of a purely Yukawa and purely Newtonian potential are also explored.


Investigating Diel, Seasonal, And Interannual Variability Of Dissolved And Particulate Stable Carbon Isotope Values In A Eutrophic Boreal Lake, Rachel Henderson Jan 2020

Investigating Diel, Seasonal, And Interannual Variability Of Dissolved And Particulate Stable Carbon Isotope Values In A Eutrophic Boreal Lake, Rachel Henderson

Theses and Dissertations (Comprehensive)

Lakes are globally significant sources, sinks, and conduits of carbon. Cultural eutrophication of freshwater promotes the growth of phytoplankton blooms, which can transform, respire, and sequester large amounts of carbon. Analysis of stable carbon isotopes is a common tool to study the movement of carbon through the aquatic carbon cycle. The causes of temporal variability in δ13C values at different timescales are not well understood, and differ between lakes. In this study, I investigated diel, seasonal, and interannual variability in δ13C values of dissolved inorganic carbon (DIC) and particulate organic carbon (POC) in Lake 227, an …


Reconstructing Hydrologic Conditions And Metals Supplied By The Peace River To The Peace-Athabasca Delta, Jelle André Faber Jan 2020

Reconstructing Hydrologic Conditions And Metals Supplied By The Peace River To The Peace-Athabasca Delta, Jelle André Faber

Theses and Dissertations (Comprehensive)

The Peace-Athabasca Delta (PAD) in northern Alberta, Canada, is recognized internationally for its ecological, historical, and cultural significance. The delta is mostly within Wood Buffalo National Park, a UNESCO World Heritage Site, and is a Ramsar Wetland of International Importance. The construction of the WAC Bennett Dam (1967) and the Site C Dam (ongoing, 2024) on the Peace River, and expansion of the Alberta Oil Sands industry along the Athabasca River have raised concerns over water quantity and quality in the delta. When industry operations began, effective monitoring had not been implemented. Consequently, pre-industrial reference conditions are unknown and can …


Aggregate Loss Model With Poisson-Tweedie Loss Frequency, Si Chen Jan 2020

Aggregate Loss Model With Poisson-Tweedie Loss Frequency, Si Chen

Theses and Dissertations (Comprehensive)

The aggregate loss model has applications in various areas such as financial risk management and actuarial science. The aggregate loss is the summation of all random losses occurred in a period, and it is governed by both the loss severity and the loss frequency. While the impact of the loss severity on aggregate loss is well studied, less focus is paid on the influence of loss frequency on aggregate loss, which motivates our study. In this thesis, we enrich the aggregate loss framework by introducing the Poisson-Tweedie distribution as a candidate for modelling loss frequency, prove the closedness of Poisson-Tweedie …