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Articles 511 - 540 of 37042

Full-Text Articles in Physical Sciences and Mathematics

Engine Performance And Emissions Improvement Study On Direct Injection Of Diesel/Ammonia Dual Fuel By Adding Cng As Partially Premixed Charge, Medhat Elkelawy Prof. Dr, Eng., Hagar Alm-Eldin Bastawissi Prof. Dr., Mohammed Osama Elsamadony Dr. Eng., Abdallah Salem Abdalhadi Eng. Jan 2024

Engine Performance And Emissions Improvement Study On Direct Injection Of Diesel/Ammonia Dual Fuel By Adding Cng As Partially Premixed Charge, Medhat Elkelawy Prof. Dr, Eng., Hagar Alm-Eldin Bastawissi Prof. Dr., Mohammed Osama Elsamadony Dr. Eng., Abdallah Salem Abdalhadi Eng.

Journal of Engineering Research

Researchers have recently moved on in their studies to find a solution to prevent or reduce this problem. There have been directions taken by researchers to solve the problem, including, replacing fossil fuels with environmentally friendly types or by combining two or more types of fuel. This is by modifying fuel injection systems as appears in the PCCI, RCCI, or HCCI systems, or working to integrate the two trends by using new injection systems and burning alternative fuels with fossil fuels. Therefore, the trend has good results on the specific consumption of fuel, raising thermal efficiency, and working to reduce …

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Experimental Study On The Impact Of Secondary Air Injection And Different Swirl Van Angles On Premixed Turbulent Flame Propagation And Emission Behaviors, Medhat Elkelawy Prof. Dr. Eng., E. A. El Shenawy Prof. Dr., Hagar Alm-Eldin Bastawissi Prof. Dr. Eng., Ibrahim Ali Mousa Eng., Mohamed M. Abdel-Raouf Ibrahim Dr. Eng. Jan 2024

Experimental Study On The Impact Of Secondary Air Injection And Different Swirl Van Angles On Premixed Turbulent Flame Propagation And Emission Behaviors, Medhat Elkelawy Prof. Dr. Eng., E. A. El Shenawy Prof. Dr., Hagar Alm-Eldin Bastawissi Prof. Dr. Eng., Ibrahim Ali Mousa Eng., Mohamed M. Abdel-Raouf Ibrahim Dr. Eng.

Journal of Engineering Research

The objective of the present paper is to investigate experimentally the flame characteristics utilizing different secondary air inlet direction for different primary air swirl numbers and equivalence fuel-air ratios. In this study, an experimental test rig was carried out to investigate the flame temperature and emission behavior with flame length at the equivalence fuel-air ratios taken0.96, 0.80, 0.70, and 0.60, and swirl vane angles were varied as 20, 30, 45, and 60° to generate different swirl numbers of 0.26, 0.416, 0.71 and 1.23, respectively. In addition to the introduction of secondary air in test combustor, whereas the primary air and …

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The Effect Of An Existing Tunnel And A Newly Excavated Tunnel On Ground Loss Beneath Sand Slope-3d Numerical Study, Ashraf Nazir, Ahmed Nasr, Asmaa Saeed Jan 2024

The Effect Of An Existing Tunnel And A Newly Excavated Tunnel On Ground Loss Beneath Sand Slope-3d Numerical Study, Ashraf Nazir, Ahmed Nasr, Asmaa Saeed

Journal of Engineering Research

Abstract- Most researchers perform their numerical models for tunnels by modeling perfectly horizontal ground surfaces above the tunnels. The prediction of surface settlement of a sandy slope due to the interaction mechanism between the slope and the tunnels is one of the critical problems in urban areas. As a result, in this work, a numerical analysis using PLAXIS 3D TUNNEL has been performed to investigate the effect of tunnel excavation on the deformation of a shallow sandy slope, and empirically by the Herzog method. The study also assesses the influence of parameters on slope deformation that have not been …

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Utilization Of Adomain Decomposition Method And Laplace Transform To Study Fractional Kdv And Fractional Benjamin Models Via Caputo Fractional Operator, Muhammad Sohail, Hina Younis Jan 2024

Utilization Of Adomain Decomposition Method And Laplace Transform To Study Fractional Kdv And Fractional Benjamin Models Via Caputo Fractional Operator, Muhammad Sohail, Hina Younis

International Journal of Emerging Multidisciplinaries: Mathematics

In the present study, we implement Adomian decomposition method (ADM) to solve fractional potential Korteweg-de Vries (p-KdV) and Benjamin models. The investigated approach is a hybrid of the Adomian decomposition method and the Laplace transform, and the fractional operator developed by Caputo has been utilized in the present research. In a vast accessible domain, the proposed solution tackle impacts and regulates the gained conclusions. Additionally, it provides a simple technique for determining the point of convergence region of the derived result. To ensure that the LADM is realistic and dependable, mathematical simulations for each equation were run, and the results …

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Future Frame Prediction Using Generative Adversarial Networks, Nishtha Jatana, Deekshant Wadhwa, Nitesh Kumar Singh, Oday Ali Hassen, Charu Gupta, Saad Mohammed Darwish, Sundws Mustafa Mohammed, Dhyeauldeen Ahmed Farhan, Ansam Ali Abdulhussein Jan 2024

Future Frame Prediction Using Generative Adversarial Networks, Nishtha Jatana, Deekshant Wadhwa, Nitesh Kumar Singh, Oday Ali Hassen, Charu Gupta, Saad Mohammed Darwish, Sundws Mustafa Mohammed, Dhyeauldeen Ahmed Farhan, Ansam Ali Abdulhussein

Karbala International Journal of Modern Science

The ability of a human to anticipate what is going to happen in the near future given the current situation helps in making intelligent decisions about how to react in that situation. In this paper, we have developed multiple Deep Neural Network models, intending to generate the next frame in a sequence given previous frames. In recent years, Generative Adversarial Networks (GAN) have shown promising results in the field of image generation. Hence, in this paper, we aim to create and compare two Generative Adversarial Models created for Future Frame Prediction by combining GANs with convolutional neural networks, Long Short-Term …

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Treatment Of Oil Refinery Wastewater Polluted By Heavy Metal Ions Via Adsorption Technique Using Non-Valuable Media: Cadmium Ions And Buckthorn Leaves As A Study Case, Salem Jawad Alhamd, Mohammed Nsaif Abbas, Mehrdad Manteghian, Thekra Atta Ibrahim, Karar Dawood Salman Jarmondi Jan 2024

Treatment Of Oil Refinery Wastewater Polluted By Heavy Metal Ions Via Adsorption Technique Using Non-Valuable Media: Cadmium Ions And Buckthorn Leaves As A Study Case, Salem Jawad Alhamd, Mohammed Nsaif Abbas, Mehrdad Manteghian, Thekra Atta Ibrahim, Karar Dawood Salman Jarmondi

Karbala International Journal of Modern Science

This study focuses on the removal of cadmium ions generated by oil refinery wastewater, employing an agricultural by-product. Buckthorn leaves, sourced from Baghdad and Diyala provinces, underwent preparation, including washing, drying, crushing, and sieving before being utilized in experiments. Batch experiments were conducted using simulated solutions to assess the impact of six key adsorption design parameters: pH, cadmium concentration, agitation speed, contact time, adsorbent dosage, and temperature. The highest adsorption efficiency, reaching 94.4367%, was directly correlated with contact time, adsorbent dosage, pH value, and agitation speed, and inversely related to other variables. Morphological studies on the treated adsorbent, indicated structural …

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On The Singular Pebbling Number Of A Graph, Harmony R. Morris Jan 2024

On The Singular Pebbling Number Of A Graph, Harmony R. Morris

Rose-Hulman Undergraduate Mathematics Journal

In this paper, we define a new parameter of a connected graph as a spin-off of the pebbling number (which is the smallest t such that every supply of t pebbles can satisfy every demand of one pebble). This new parameter is the singular pebbling number, the smallest t such that a player can be given any configuration of at least t pebbles and any target vertex and can successfully move pebbles so that exactly one pebble ends on the target vertex. We also prove that the singular pebbling number of any graph on 3 or more vertices is equal …

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Compartmental Modeling For The Neophyte: An Application Of Berkeley Madonna, Olcay Akman, Siddharth Bhumpelli, Cody Cline, Christopher Hay-Jahans Jan 2024

Compartmental Modeling For The Neophyte: An Application Of Berkeley Madonna, Olcay Akman, Siddharth Bhumpelli, Cody Cline, Christopher Hay-Jahans

Spora: A Journal of Biomathematics

Compartmental modeling serves as a necessary framework in many fields, especially biomathematics and ecology. This article introduces readers to a user-friendly approach to constructing compartmental models and solving the resulting systems of differential equations to simulate real-world applications. The platform used is Berkeley Madonna, a software package that has an intuitive graphical interface which empowers users—even those with limited mathematical and programming backgrounds—to focus on modeling concepts rather than mathematical or programming intricacies. This makes Berkeley Madonna an ideal platform for students, educators, and researchers.

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Synchronicity: An Analysis Of Einstein's Halfway Rule, Preslava Nikolova Jan 2024

Synchronicity: An Analysis Of Einstein's Halfway Rule, Preslava Nikolova

Rushton Journal of Undergraduate Humanities Research

For the modern world to function, Global Positioning System satellites must synchronize to clocks on Earth. This paper examines a concept that underlies GPS systems, namely Albert Einstein’s halfway rule—the idea that a line of simultaneity exists between two events in different systems. This essay discusses how Einstein used conventionalist methods to establish ½ as a constant value for σ to take advantage of the property of symmetry.

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Nonlinear Dynamics Of Mountain Pine Beetle Populations: Discussion Of Forestry Policy, A Survey Of Existing Mathematical Models, And Code Base Demonstration, Scott A. Strong, Maya Maes-Johnson Jan 2024

Nonlinear Dynamics Of Mountain Pine Beetle Populations: Discussion Of Forestry Policy, A Survey Of Existing Mathematical Models, And Code Base Demonstration, Scott A. Strong, Maya Maes-Johnson

CODEE Journal

This article presents existing mathematical models associated with mountain pine beetle populations in lodgepole pine forests, whose reproductive cycle requires the destruction of colonized host trees, decreasing timber availability/quality, and providing fuel sources for wildfires. With the existence of a positive-feedback loop with environmental warming, the need for intervention and management is clear. However, the legislative responses to the focusing events from our 2000-2010 North American epidemics are characterized as under-leveraged. While the reasons for this are multifaceted, increasing the capacity of STEM-informed individuals to take part in quantitative modeling of the underlying ecosystem generates awareness and provides pathways connecting …

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To Open Or Not To Open: Developing A Covid-19 Model Specific To Small Residential Campuses, Christina Joy Edholm, Maryann Hohn, Nicole Lee Falicov, Emily Lee, Lily Natasha Wartman, Ami Radunskaya Jan 2024

To Open Or Not To Open: Developing A Covid-19 Model Specific To Small Residential Campuses, Christina Joy Edholm, Maryann Hohn, Nicole Lee Falicov, Emily Lee, Lily Natasha Wartman, Ami Radunskaya

CODEE Journal

In May 2020, administrators of residential colleges struggled with the decision of whether or not to open their campuses in the Fall semester of 2020. To help guide this decision, we formulated an ODE model capturing the dynamics of the spread of COVID-19 on a residential campus. In order to provide as much information as possible for administrators, the model accounts for the different behaviors, susceptibility, and risks in the various sub-populations that make up the campus community. In particular, we start with a traditional SEIR model and add compartments representing relevant variables, such as quarantine compartments and a hospitalized …

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Fitting A Covid-19 Model Incorporating Senses Of Safety And Caution To Local Data From Spartanburg County, South Carolina, D. Chloe Griffin, Amanda Mangum Jan 2024

Fitting A Covid-19 Model Incorporating Senses Of Safety And Caution To Local Data From Spartanburg County, South Carolina, D. Chloe Griffin, Amanda Mangum

CODEE Journal

Common mechanistic models include Susceptible-Infected-Removed (SIR) and Susceptible-Exposed-Infected-Removed (SEIR) models. These models in their basic forms have generally failed to capture the nature of the COVID-19 pandemic's multiple waves and do not take into account public policies such as social distancing, mask mandates, and the ``Stay-at-Home'' orders implemented in early 2020. While the Susceptible-Vaccinated-Infected-Recovered-Deceased (SVIRD) model only adds two more compartments to the SIR model, the inclusion of time-dependent parameters allows for the model to better capture the first two waves of the COVID-19 pandemic when surveillance testing was common practice for a large portion of the population. We find …

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Differential Equations For A Changing World:How To Engage Students In Learning And Applying Differential Equations, Biyong Luo Jan 2024

Differential Equations For A Changing World:How To Engage Students In Learning And Applying Differential Equations, Biyong Luo

CODEE Journal

In this article, I share my decade-long experience teaching an intensive five-week summer Differential Equation course covering complex topics and tips for creating an interactive and supportive learning environment to optimize student engagement. This article provides my detailed approach to planning and teaching an asynchronous course with rigor and flexibility for each student. An interactive teaching approach and variety of learning activities will augment students’ mathematical fluency and appreciation of the importance of differential equations in modeling a wide variety of real-world situations with special attention to ways differential equations can be relevant to creating public policy.

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Investigation Of Earthquake Sequence And Stress Transfer In The Eastern Anatolia Fault Zone By Coulomb Stress Analysis, Hamdi̇ Alkan, Aydin Büyüksaraç, Özcan Bektaş Jan 2024

Investigation Of Earthquake Sequence And Stress Transfer In The Eastern Anatolia Fault Zone By Coulomb Stress Analysis, Hamdi̇ Alkan, Aydin Büyüksaraç, Özcan Bektaş

Turkish Journal of Earth Sciences

A devastating earthquake with a magnitude of (Mw = 7.7) occurred on February 06, 2023, in the Pazarcık segment of the Eastern Anatolian Fault Zone, which has not shown major earthquake activity for a long time. On the same day, another earthquake with a magnitude of (Mw = 7.6) occurred in Ekinözü-Elbistan (Kahramanmaraş) in the northwest. Three more earthquakes with magnitudes of Mw = 6.6, Mw = 5.9, and ML = 5.7 occurred on the same day, and significant damage, loss of life, and property occurred in 11 provinces and districts. A sixth earthquake occurred with Mw = 6.4 magnitude …

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Preliminary Results Of The Great Kahramanmaraş 6 February 2023 Earthquakes (Mw 7.7 And 7.6) And 20 February 2023 Antakya Earthquake (Mw 6.4), Eastern Türkiye, Şule Gürboğa, Önder Kayadi̇bi̇, Hafi̇ze Akilli, Serap Arikan, Sevi̇lay Tan Jan 2024

Preliminary Results Of The Great Kahramanmaraş 6 February 2023 Earthquakes (Mw 7.7 And 7.6) And 20 February 2023 Antakya Earthquake (Mw 6.4), Eastern Türkiye, Şule Gürboğa, Önder Kayadi̇bi̇, Hafi̇ze Akilli, Serap Arikan, Sevi̇lay Tan

Turkish Journal of Earth Sciences

The first MW 7.7 and second MW 7.6 Kahramanmaraş earthquakes were the strongest tectonic events in Eastern Türkiye since the MW 7.9 Erzincan earthquake in 1939. The first and second events occurred on the Pazarcık and Çardak segments of the East Anatolian Fault System, respectively. A subsequent significant earthquake of MW 6.4 occurred in the Antakya fault zone. We summarize preliminary earthquake data and share our previous field observations to better understand the mechanism and provide scientific consequences for future investigations and layout planning. After combining the field observations, kinematic analysis of fault surfaces, investigations of orthophotos, characteristics of mainshocks, …

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Surface Rupture During The 6th Of February 2023 Mw 7.6 Elbistan-Ekinözü (Kahramanmaraş) Earthquake: Implications For Fault Rupture Dynamics Along The Northern Branch Of East Anatolian Fault Zone, Mustafa Softa, Fi̇kret Koçbulut, Eli̇f Akgün, Ercan Aksoy, Hasan Sözbi̇li̇r, Orhan Tatar, Volkan Karabacak, Çağlar Özkaymak, Mehmet Utku, Özkan Cevdet Özdağ, Recep Çakir, Ahmet Demi̇r, Gökhan Arslan Jan 2024

Surface Rupture During The 6th Of February 2023 Mw 7.6 Elbistan-Ekinözü (Kahramanmaraş) Earthquake: Implications For Fault Rupture Dynamics Along The Northern Branch Of East Anatolian Fault Zone, Mustafa Softa, Fi̇kret Koçbulut, Eli̇f Akgün, Ercan Aksoy, Hasan Sözbi̇li̇r, Orhan Tatar, Volkan Karabacak, Çağlar Özkaymak, Mehmet Utku, Özkan Cevdet Özdağ, Recep Çakir, Ahmet Demi̇r, Gökhan Arslan

Turkish Journal of Earth Sciences

On the 6th of February 2023, Mw 7.7 Pazarcık (Kahramanmaraş) and Mw 7.6 Ekinözü (Kahramanmaraş) earthquakes that occurred in Türkiye are devastating earthquake series that filled the existing seismic gaps on East Anatolian Fault Zone on the same day. The first Mw 7.7 earthquake caught most people in their sleep and 9 h later, a second one was triggered, ending up with more than 50k death toll, widespread damage to buildings, and massive landslides. This study presents the surface rupture geometry and coseismic displacement characteristics determined with field observations immediately after February 6, 2023, Ekinözü (Kahramanmaraş, Türkiye) earthquake (Mw 7.6). …

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Tepehan Rockslide: A Large-Scale Earthquake-Induced Geological Structure Formed By Mw:7.8 Kahramanmaraş (Pazarcık) Earthquake, Türkiye, Ökmen Sümer Jan 2024

Tepehan Rockslide: A Large-Scale Earthquake-Induced Geological Structure Formed By Mw:7.8 Kahramanmaraş (Pazarcık) Earthquake, Türkiye, Ökmen Sümer

Turkish Journal of Earth Sciences

Three devastating and powerful earthquakes hit the southeastern and eastern parts of Turkey and the northestern part of Syria in February of 2023, causing many earthquake-induced slope movements. One of these major mass movements is called the “Tepehan Rockslide”, which was formed by the first Mw: 7.8 earthquake on February 6th, 2023 at Pazarcık (Kahramanmaraş) located in the Altınözü district of Hatay province. The rockslide involved the movement of Middle Miocene basement rocks that consist of clayey limestone, marl, and fine-grained clastic sedimentary rocks. The morphogenetic evaluation of the structure reveals that the Tepehan Rockslide is a very rapidly developed …

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Response Of Water Resources To The Kahramanmaraş Earthquakes (Mw 7.7 And Mw 7.6) That Occurred On February 6, 2023, On The East Anatolian Fault Zone (Türkiye), Celaletti̇n Şi̇mşek, Görkem Akinci, Okan Fistikoğlu, Kerem Canli, Hasan Sözbi̇li̇r, Azi̇ze Ayol, Efem Bi̇lgi̇ç Jan 2024

Response Of Water Resources To The Kahramanmaraş Earthquakes (Mw 7.7 And Mw 7.6) That Occurred On February 6, 2023, On The East Anatolian Fault Zone (Türkiye), Celaletti̇n Şi̇mşek, Görkem Akinci, Okan Fistikoğlu, Kerem Canli, Hasan Sözbi̇li̇r, Azi̇ze Ayol, Efem Bi̇lgi̇ç

Turkish Journal of Earth Sciences

On February 6, 2023, two destructive earthquakes of 7.7 MW and 7.6 MW occurred in Pazarcık (Kahramanmaraş) and Elbistan (Kahramanmaraş) at 04:17 and 13:24 hours, respectively. These earthquakes caused a surface rupture with a total length of 450 km in the region with an average displacement of 3 m between the Arabian and Anatolian plates. This study was conducted to investigate the physical deformation of the aquifer system and the current water quality characteristics in the affected region utilizing field observations and on-site analysis of water sources and tap water. The study revealed significant physical changes in the karstic springs …

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Soil Liquefaction And Subsidence Disaster In İskenderun Related To The 6 February 2023 Pazarcık (Mw: 7.7) And 20 February Defne (Mw: 6.4) Earthquakes, Türkiye, Hüseyi̇n Öztürk, Craig A. Davis, İbrahi̇m Kuşku, Süleyman Dalğiç, Cem Kasapçi, Muharrem Alper Şengül Jan 2024

Soil Liquefaction And Subsidence Disaster In İskenderun Related To The 6 February 2023 Pazarcık (Mw: 7.7) And 20 February Defne (Mw: 6.4) Earthquakes, Türkiye, Hüseyi̇n Öztürk, Craig A. Davis, İbrahi̇m Kuşku, Süleyman Dalğiç, Cem Kasapçi, Muharrem Alper Şengül

Turkish Journal of Earth Sciences

The Mw 7.7 Pazarcık earthquake on February 06, 2023, struck southern Türkiye, causing typical liquefaction along the shores of İskenderun Bay. This liquefaction was characterized by lateral spreading, subsidence, and flooding. Subsidence-triggered sand ejecta, water flows, and opening cracks were identified in areas spanning approximately 2 km in length and 300 m in width. Based on coastal references such as lighthouses or harbor platforms, settlements of 0.8 m and lateral spreading of 0.4% were recorded along the coastal zone following the Pazarcık earthquake. According to camera recordings, liquefaction-related water and silty sand outflows occurred 29 min after the earthquake. The …

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Modeling Aircraft Takeoffs, Catherine Cavagnaro Jan 2024

Modeling Aircraft Takeoffs, Catherine Cavagnaro

CODEE Journal

Real-world applications can demonstrate how mathematical models describe and provide insight into familiar physical systems. In this paper, we apply techniques from a first-semester differential equations course that shed light on a problem from aviation. In particular, we construct several differential equations that model the distance that an aircraft requires to become airborne. A popular thumb rule that pilots have used for decades appears to emanate from one of these models. We will see that this rule does not follow from a representative model and suggest a better method of ensuring safety during takeoff. Aircraft safety is definitely a matter …

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Applying The Sir Model: Can Students Advise The Mayor Of A Small Community?, Carrin Goosen, Mark I. Nelson, Mahime Watanabe Jan 2024

Applying The Sir Model: Can Students Advise The Mayor Of A Small Community?, Carrin Goosen, Mark I. Nelson, Mahime Watanabe

CODEE Journal

This is an account of a modelling scenario that uses the sir epidemic model. It was used in a third year applied mathematics subject. All students were enrolled in a mathematics degree of some type. Students are presented with the results of a test carried out on 100 individuals in a community containing 3000 people. From this they determined the number of infectious and recovered individuals in the population. Given the per capita recovery rate and making a suitable assumption about the number of infectious individuals at the start of the epidemic, they then estimate the infectious contact rate and …

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Ode Models Of Wealth Concentration And Taxation, Bruce Boghosian, Christoph Borgers Jan 2024

Ode Models Of Wealth Concentration And Taxation, Bruce Boghosian, Christoph Borgers

CODEE Journal

We refer to an individual holding a non-negligible fraction of the country’s total wealth as an oligarch. We explain how a model due to Boghosian et al. can be used to explore the effects of taxation on the emergence of oligarchs. The model suggests that oligarchs will emerge when wealth taxation is below a certain threshold, not when it is above the threshold. The underlying mechanism is a transcritical bifurcation. The model also suggests that taxation of income and capital gains alone cannot prevent the emergence of oligarchs. We suggest several opportunities for students to explore modifications of the model.

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Raising Student Awareness Of Environmental Issues Via Writing Assignments With Differential Equations, Michelle L. Ghrist Jan 2024

Raising Student Awareness Of Environmental Issues Via Writing Assignments With Differential Equations, Michelle L. Ghrist

CODEE Journal

In this paper, I discuss two environmentally-focused writing assignments that I developed and implemented in recent integral calculus and differential equations courses. These models of carbon storage and PCB’s in a river provide interesting applications of one-compartment mixing problems. The assignments were intended to focus student attention on sustainability concerns while also developing other essential skills. I discuss these assignments and their effect on my students’ technical writing and environmental awareness. Detailed introductory instructions and mostly complete solutions to these assignments appear in the appendices, to include sample student work.

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Blue Whale And Krill Populations Modeling, Li Zhang Jan 2024

Blue Whale And Krill Populations Modeling, Li Zhang

CODEE Journal

We present an intriguing topic in an undergraduate mathematical modeling course where predator-prey models are taught to our students. We describe modeling activities and the use of technology that can be implemented in teaching this topic. Through modeling activities, students are expected to use the numerical and graphical methods to observe the qualitative long-term behavior of predator and prey populations. Although there are other choices of predators and prey, we find that using blue whales and krill as predator and prey, respectively, would be most beneficial in strengthening our students' awareness of protecting endangered species and its impact on climate …

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Odes And Mandatory Voting, Christoph Borgers, Natasa Dragovic, Anna Haensch, Arkadz Kirshtein, Lilla Orr Jan 2024

Odes And Mandatory Voting, Christoph Borgers, Natasa Dragovic, Anna Haensch, Arkadz Kirshtein, Lilla Orr

CODEE Journal

This paper presents mathematics relevant to the question whether voting should be mandatory. Assuming a static distribution of voters’ political beliefs, we model how politicians might adjust their positions to raise their share of the vote. Various scenarios can be explored using our app at https: //centrism.streamlit.app/. Abstentions are found to have great impact on the dynamics of candidates, and in particular to introduce the possibility of discontinuous jumps in optimal candidate positions. This is an unusual application of ODEs. We hope that it might help engage some students who may find it harder to connect with the more customary …

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Solar Panels, Euler’S Method And Community-Based Projects: Connecting Differential Equations With Climate Change, Victor J. Donnay Jan 2024

Solar Panels, Euler’S Method And Community-Based Projects: Connecting Differential Equations With Climate Change, Victor J. Donnay

CODEE Journal

How does mathematics connect with the search for solutions to the climate emergency? One simple connection, which can be explored in an introductory differential equations course, can be found by analyzing the energy generated by solar panels or wind turbines. The power generated by these devices is typically recorded at standard time intervals producing a data set which gives a discrete approximation to the power function $P(t)$. Using numerical techniques such as Euler’s method, one can determine the energy generated. Here we describe how we introduce the topic of solar power, apply Euler’s method to determine the energy generated, and …

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Using A Sand Tank Groundwater Model To Investigate A Groundwater Flow Model, Christopher Evrard, Callie Johnson, Michael A. Karls, Nicole Regnier Jan 2024

Using A Sand Tank Groundwater Model To Investigate A Groundwater Flow Model, Christopher Evrard, Callie Johnson, Michael A. Karls, Nicole Regnier

CODEE Journal

A Sand Tank Groundwater Model is a tabletop physical model constructed of plexiglass and filled with sand that is typically used to illustrate how groundwater water flows through an aquifer, how water wells work, and the effects of contaminants introduced into an aquifer. Mathematically groundwater flow through an aquifer can be modeled with the heat equation. We will show how a Sand Tank Groundwater Model can be used to simulate groundwater flow through an aquifer with a no flow boundary condition.

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The Valuation Of Exit Option In A Lignite Mine Using Monte Carlo Simulation, Marcin Pawlak, Tomasz Wiśniewski Jan 2024

The Valuation Of Exit Option In A Lignite Mine Using Monte Carlo Simulation, Marcin Pawlak, Tomasz Wiśniewski

Journal of Sustainable Mining

This study aims to demonstrate the application of simulation techniques to the valuation of real options. The nature of the paper is methodological and empirical. The purpose of the valuation of the option to close a lignite mine in Poland is to demonstrate the methodology and advantages of employing Monte Carlo simulation in the valuation of real options. Close to actual numerical data reveals a complex optimization problem in the context of strategy selection by decision-makers. Numerous factors (extraction costs, reclamation costs, the write-off for the reclamation fund, etc.), their interpenetration and multilevel influence on the decision to close the …

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Mathematical Model For The Management Of The Wave Processes In Three-Winding Transformers With Consideration Of The Main Magnetic Flux In Mining Industry, M. S. Seheda, O. S. Beshta, P. F. Gogolyuk, Yu. V. Blyznak, R. D. Dychkovskyi, A. Smoliński Jan 2024

Mathematical Model For The Management Of The Wave Processes In Three-Winding Transformers With Consideration Of The Main Magnetic Flux In Mining Industry, M. S. Seheda, O. S. Beshta, P. F. Gogolyuk, Yu. V. Blyznak, R. D. Dychkovskyi, A. Smoliński

Journal of Sustainable Mining

The aim of the work is to study the wave processes in three-winding power transformers caused by impulse overvoltage, to create an improved mathematical model for reproducing the process of distribution and transmission of the impulse in the windings of a three-winding power transformer. A mathematical model has been developed for the study of internal overvoltage in the windings of three-winding power transformers, based on the proposed substitute circuit of an infinitesimal element, taking into account the longitudinal and transverse inductive connections between the turns of the winding, the electromagnetic connections between the windings and the flux splitting from the …

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The Effect Of Blasting Using Low-Density Emulsion Explosives, Vinko Škrlec, Mario Dobrilović, Barbara Štimac Tumara, Vječislav Bohanek Jan 2024

The Effect Of Blasting Using Low-Density Emulsion Explosives, Vinko Škrlec, Mario Dobrilović, Barbara Štimac Tumara, Vječislav Bohanek

Journal of Sustainable Mining

Low-density emulsion explosives are essentially blends of an emulsion matrix and a certain amount of gaseous phase inclusions acting as hot spots. With the addition of expanded polystyrene for gaseous sensibilization, the resulting explosive blend was developed to reduce peak values and pressure impulse of gaseous detonation products on surrounding rock. This resulted in a decrease in rock stress and a decrease in cracking zone width outside of the minefield boundary. The use of low-density emulsion explosives correlates with the decrease in the seismic effect of blasting, more precisely, the decrease of induced rock oscillation velocities. The low-density emulsion explosive …

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