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Articles 54121 - 54150 of 303097

Full-Text Articles in Physical Sciences and Mathematics

Providing Improved Livelihoods For Muskoka's Stakeholders In The Time Of Two Global Crises, Andrew Court '22 Aug 2021

Providing Improved Livelihoods For Muskoka's Stakeholders In The Time Of Two Global Crises, Andrew Court '22

Student Scholarship

Climate change and the coronavirus pandemic have drastically impacted the livelihoods ofMuskoka's stakeholders. Climate change has led to altered weather patterns and environments in Muskoka, which have negatively impacted stakeholders' ( defined as permanent residents, seasonal residents and tourists) built infrastructure, mental and physical health, and these effects are only expected to worsen in the coming decades. Similarly, the coronavirus pandemic has caused many physical and mental health problems for Muskoka's stakeholders and has also led to tensions and anxieties regarding opinions about whether or not every stakeholder should be able to access the region during the pandemic. Although coronavirus …

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To Know The Land With Hands And Minds: Negotiating Agricultural Knowledge In Late-Nineteenth-Century New England And Westphalia, Justus Hillebrand Aug 2021

To Know The Land With Hands And Minds: Negotiating Agricultural Knowledge In Late-Nineteenth-Century New England And Westphalia, Justus Hillebrand

Electronic Theses and Dissertations

Ever since the eighteenth century, experts have tried to tell farmers how to farm. The agricultural enlightenment in Europe marked the beginning of a long arc of new experts aiming to change agricultural knowledge and practice. This dissertation analyzes the pivotal period in the late nineteenth and early twentieth century in Germany and the United States when scientists, improvers, and market agents began to develop comprehensive ways to communicate agricultural innovation to farmers. In a functional approach to analyzing the negotiation of agricultural knowledge through its communication in things, words, and practices, this dissertation argues that the process of change …

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Application Of Machine Learning Techniques To Classify And Identify Galaxy Merger Events In The Candels Field, Alex Koch Aug 2021

Application Of Machine Learning Techniques To Classify And Identify Galaxy Merger Events In The Candels Field, Alex Koch

Electronic Theses and Dissertations

Galaxy mergers are dynamic systems that offer us a glimpse into the evolution of the cosmos and the galaxies that constitute it. However, with the advent of large astronomical surveys, it is becoming increasingly difficult to rely on humans to classify the vast number of astronomical images collected every year and find the images that capture these systems. In recent years, researchers have increasingly relied on machine learning and computer vision classifiers, and while these techniques have proven useful for classifying broad galaxy morphologies, they have struggled to identify galaxy mergers. A random forest classifier was applied to a subset …

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An Investigation Of Students' Use And Understanding Of Evaluation Strategies, Abolaji R. Akinyemi Aug 2021

An Investigation Of Students' Use And Understanding Of Evaluation Strategies, Abolaji R. Akinyemi

Electronic Theses and Dissertations

One expected outcome of physics instruction is that students develop quantitative reasoning skills, including evaluation of problem solutions. To investigate students’ use of evaluation strategies, we developed and administered tasks prompting students to check the validity of a given expression. We collected written (N>673) and interview (N=31) data at the introductory, sophomore, and junior levels. Tasks were administered in three different physics contexts: the velocity of a block at the bottom of an incline with friction, the electric field due to three point charges of equal magnitude, and the final velocities of two masses in an elastic collision. Responses …

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Asymmetric Synthesis Of Phosphate Mimics: From Chemistry To Biotechnology, Ahmed Numan Aug 2021

Asymmetric Synthesis Of Phosphate Mimics: From Chemistry To Biotechnology, Ahmed Numan

Electronic Theses and Dissertations

Oligonucleotide based therapeutics have been pursued in the clinic for the treatment of many disease indications. However, unmodified oligonucleotides are polyanionic macromolecules with poor drug-like properties. Modifications of the phosphodiester backbone provide resistance to nucleases in vivo, making them more efficacious than unmodified nucleotides. However, these backbone modifications have added the structural complexity of a stereogenic phosphorus center. Stereochemically pure isomers exhibit differential efficiency dependent on its enantiopurity. The catalytic, stereocontrolled synthesis of a phosphorus-stereogenic center is challenging, and traditionally, depends on a resolution or use of stochiometric auxiliaries. Herein, asymmetric nucleophilic catalysis has been investigated to provide enantio-enriched phosphonates …

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Progress And Prospect On Monitoring And Evaluation Of United Nations Sdg 6 (Clean Water And Sanitation) Target, Shanlong Lu, Li Jia, Yunzhong Jiang, Zongming Wang, Hongtao Duan, Ming Shen, Yu Tian, Jing Lu Aug 2021

Progress And Prospect On Monitoring And Evaluation Of United Nations Sdg 6 (Clean Water And Sanitation) Target, Shanlong Lu, Li Jia, Yunzhong Jiang, Zongming Wang, Hongtao Duan, Ming Shen, Yu Tian, Jing Lu

Bulletin of Chinese Academy of Sciences (Chinese Version)

Clean water and sanitation (SDG 6) is one of the 17 Sustainable Development Goals (SDGs) of the United Nations, but so far, the world is not on the right track to achieve SDG 6 targets. In order to change this situation and lead the world to achieve the goal of sustainable water resources management, the United Nations initiated the SDG 6 global acceleration framework including financing, data and information, capacity development, innovation, and governance. From the perspective of data and information that serving SDG 6 target monitoring and evaluation, this study analyzes the current global data progress, the role of …

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Big Earth Data Promotes Assessment Of Even Development, Yali Liu, Yanfen Wang, Jianqing Du, Huadong Guo, Bingfang Wu, Bojie Fu Aug 2021

Big Earth Data Promotes Assessment Of Even Development, Yali Liu, Yanfen Wang, Jianqing Du, Huadong Guo, Bingfang Wu, Bojie Fu

Bulletin of Chinese Academy of Sciences (Chinese Version)

Uneven progresses have been widely detected among goals or regions in global sustainable development, which are ascribed to the heterogeneous resource and environmental conditions and trade-offs among goals. In-depth understanding and efforts to reduce such uneven progresses are essential for the holistic achievement of the sustainable development goals (SDGs). This study discusses how bBig Earth Data supports the assessment of the even development among targets and regions by pointing out its advantages in providing high-frequency and more timely data products with higher spatial resolution for the currently poorly achieved SDGs regarding essential human needs and environmental protection. Moreover, the Big …

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Data Information: Statistics And Trends To Promote Researches On Un Sustainable Development Goals Aug 2021

Data Information: Statistics And Trends To Promote Researches On Un Sustainable Development Goals

Bulletin of Chinese Academy of Sciences (Chinese Version)

No abstract provided.

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Big Earth Data In Support Of Marine Sustainable Development, Futao Wang, Rencheng Yu, Jingxi Li, Dehua Mao, Chengyi Wang, Mingming Jia, Jingjuan Liao, Ziyuan Hu, Haifeng Gu, Qinsheng Wei, Li Zhang, Shilin Tang Aug 2021

Big Earth Data In Support Of Marine Sustainable Development, Futao Wang, Rencheng Yu, Jingxi Li, Dehua Mao, Chengyi Wang, Mingming Jia, Jingjuan Liao, Ziyuan Hu, Haifeng Gu, Qinsheng Wei, Li Zhang, Shilin Tang

Bulletin of Chinese Academy of Sciences (Chinese Version)

The health and safety of marine ecosystems are directly related to the health and well-being of all mankind. Factors such as insufficient effective monitoring data and lack of scientific decision-making information have affected the smooth implementation of the marine sustainable development goals (SDG 14) to a certain extent. Big Earth Data possesses macroscopic, dynamic and objective monitoring capabilities, and can play an important role in supporting the realization of the sustainable development goals of the ocean. With the support of the Strategic Priority Research Program of Chinese Academy of Sciences, and based on technologies and methods related to Big Earth …

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Urban Sustainable Development Evaluation With Big Earth Data: Data, Indicators, And Methods, Jun Gao, Zhonghao Zhang, Weiyue Li, Fengyuan Sun, Yina Hu, Liangxu Wang, Jing Fu, Xin Li, Guodong Cheng Aug 2021

Urban Sustainable Development Evaluation With Big Earth Data: Data, Indicators, And Methods, Jun Gao, Zhonghao Zhang, Weiyue Li, Fengyuan Sun, Yina Hu, Liangxu Wang, Jing Fu, Xin Li, Guodong Cheng

Bulletin of Chinese Academy of Sciences (Chinese Version)

The sustainable development of cities is the key to achieving the United Nations 2030 Sustainable Development Goals (SDGs). There have been numbers of studies on urban sustainable development assessment, but the existing indicators are usually based on traditional statistical data, which makes urban sustainable development assessment limited in global city assessment and comparison. Big Earth Data can overcome the problems of traditional data statistics such as inconsistent statistical caliber, incomplete statistical information, and difficulty in obtaining data. With its macroscopic, dynamic, and diverse advantages, it can provide new assistance for urban sustainable development assessment. Based on the research on sustainable …

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Trends Observation: International Big Earth Data Research Situation And Hot Trends Aug 2021

Trends Observation: International Big Earth Data Research Situation And Hot Trends

Bulletin of Chinese Academy of Sciences (Chinese Version)

No abstract provided.

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Big Earth Data Research Topic Evolution And Influence Analysis, Peijun An, Xiantao Xiao, Huadong Guo, Dongmei Yan, Jialei Li Aug 2021

Big Earth Data Research Topic Evolution And Influence Analysis, Peijun An, Xiantao Xiao, Huadong Guo, Dongmei Yan, Jialei Li

Bulletin of Chinese Academy of Sciences (Chinese Version)

Big data driven data-intensive scientific discovery, and the Big Earth Data is the base and engine of Earth system science. Based on observation of natural geographical elements on different scales and acquisition of data, and the data obtained during the interdisciplinary research processes, integration and mining analysis will promote the development of Earth science to achieve significant innovation. The Big Earth Data has also become the important national strategic resources, and exerted influence on international cooperation and diplomatic relationship. In this study by means of literature metrology, the Big Earth Data literature from the Science Citation Index (SCI) and Social …

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Re-Visiting Acoustic Sounding To Advance The Measurement Of Optical Turbulence, Steven T. Fiorino, Santasri Bose-Pillai, Kevin J. Keefer Aug 2021

Re-Visiting Acoustic Sounding To Advance The Measurement Of Optical Turbulence, Steven T. Fiorino, Santasri Bose-Pillai, Kevin J. Keefer

Faculty Publications

Optical turbulence, as determined by the widely accepted practice of profiling the temperature structure constant, C2T, via the measurement of ambient atmospheric temperature gradients, can be found to differ quite significantly when characterizing such gradients via thermal-couple differential temperature sensors as compared to doing so with acoustic probes such as those commonly used in sonic anemometry. Similar inconsistencies are observed when comparing optical turbulence strength derived via C2T as compared to those through direct optical or imaging measurements of small fluctuations of the index of refraction of air (i.e., scintillation). These irregularities are especially apparent …

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Butte Priority Soils Operable Unit (Bpsou) Unreclaimed Sites -Draft Final Field Sampling Plan (Fsp) #4: Ur-16 And Ur-21, Mike Mcanulty Aug 2021

Butte Priority Soils Operable Unit (Bpsou) Unreclaimed Sites -Draft Final Field Sampling Plan (Fsp) #4: Ur-16 And Ur-21, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

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Discards & Diverse Economies: Reuse In Rural Maine, Brieanne Berry Aug 2021

Discards & Diverse Economies: Reuse In Rural Maine, Brieanne Berry

Electronic Theses and Dissertations

This dissertation presents an ethnographic exploration of diverse reuse economies in rural Maine in an effort to illuminate both how used goods move between people and organizations, as well as the value of that movement for people and communities. In response to a growing number of calls for research into the social dimensions of circular economies, this research explores the varied and uneven impacts of materials reuse as they are experienced by local participants. This work uses a qualitative approach, drawing on two main methods: participant observation in reuse establishments and in-depth, semi-structured interviews with reuse participants. This rich qualitative …

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Luminosity Functions Of Galaxy Clusters In The Aquarius And Microscopium Superclusters, Logan A. Hess Aug 2021

Luminosity Functions Of Galaxy Clusters In The Aquarius And Microscopium Superclusters, Logan A. Hess

Electronic Theses and Dissertations

We examine physical properties of several galaxy clusters located within the Aquarius (AQR) and Microscopium (MSC) super-cluster complexes via their luminosity functions, fitted using Schechter functions. Images of clusters were acquired via the DECam (Dark Energy Camera) imager of the 4-meter diameter telescope at CTIO (Cerro Tololo Inter-American Observatory). We observe six clusters in our sample; four from the Aquarius supercluster (AQR 2541, 2546, 2554, 2555) and two from the Microscopium supercluster (MSC 3695, 3696). Magnitude information and density of member galaxies in each cluster were extracted via the SExtractor software utility from obtained images. We correct for background by …

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Laser Surface Treatment And Laser Powder Bed Fusion Additive Manufacturing Study Using Custom Designed 3d Printer And The Application Of Machine Learning In Materials Science, Hao Wen Aug 2021

Laser Surface Treatment And Laser Powder Bed Fusion Additive Manufacturing Study Using Custom Designed 3d Printer And The Application Of Machine Learning In Materials Science, Hao Wen

LSU Doctoral Dissertations

Selective Laser Melting (SLM) is a laser powder bed fusion (L-PBF) based additive manufacturing (AM) method, which uses a laser beam to melt the selected areas of the metal powder bed. A customized SLM 3D printer that can handle a small quantity of metal powders was built in the lab to achieve versatile research purposes. The hardware design, electrical diagrams, and software functions are introduced in Chapter 2. Several laser surface engineering and SLM experiments were conducted using this customized machine which showed the functionality of the machine and some prospective fields that this machine can be utilized. Chapter 3 …

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Effects Of Structure, Crystallographic Orientation, And Dimensionality On Emergent Properties Of Transition Metal Oxide Thin Films, Prahald Siwakoti Aug 2021

Effects Of Structure, Crystallographic Orientation, And Dimensionality On Emergent Properties Of Transition Metal Oxide Thin Films, Prahald Siwakoti

LSU Doctoral Dissertations

SrRuO3 is the only example of ferromagnetic perovskite oxide of a 4d transition metal, wherein the electron -electron correlation is still relevant while the heavier 4d ion (Ru) gives it a larger spin-orbit coupling strength which makes it an interesting material to study. In this thesis, we present our investigation of the structure and properties of SrRuO3 thin films of varying thickness grown on [001] and [111] crystallographic orientation of the SrTiO3 substrate. For SrRuO3(001), we present microscopically the presence of 90◦ in-plane rotated structural domains that are identified by the difference in octahedral rotations and …

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Preface Of Special Issue On Big Earth Data For Implementing The Sustainable Development Goals, Jianguo Hou Aug 2021

Preface Of Special Issue On Big Earth Data For Implementing The Sustainable Development Goals, Jianguo Hou

Bulletin of Chinese Academy of Sciences (Chinese Version)

No abstract provided.

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Big Earth Data Facilitates Sustainable Development Goals, Huadong Guo, Dong Liang, Fang Chen, Zhongchang Sun, Jie Liu Aug 2021

Big Earth Data Facilitates Sustainable Development Goals, Huadong Guo, Dong Liang, Fang Chen, Zhongchang Sun, Jie Liu

Bulletin of Chinese Academy of Sciences (Chinese Version)

In 2015, the United Nations adopted 17 sustainable development goals (SDGs) to guide the economic, social, and environmental aspects of development. However, several factors have constrained the implementation of the SDGs, including uneven development, lack of data, and the interconnection and mutual restriction between the goals. In particular, the outbreak of COVID-19 pandemic in 2020 exacerbated the challenges faced by countries in implementing SDGs. This study focuses on the need to improve data services for SDGs in order to strengthen scientific research on monitoring and evaluating SDG indicators. We advocate for a scientific think tank that guides technological innovation for …

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Big Earth Data Supports Sustainable Food Production: Practices And Prospects, Lijun Zuo, Bingfang Wu, Liangzhi You, Wenjiang Huang, Ran Meng, Yingying Dong, Tianshi Pan, Yafei Wang Aug 2021

Big Earth Data Supports Sustainable Food Production: Practices And Prospects, Lijun Zuo, Bingfang Wu, Liangzhi You, Wenjiang Huang, Ran Meng, Yingying Dong, Tianshi Pan, Yafei Wang

Bulletin of Chinese Academy of Sciences (Chinese Version)

Ensuring food security is a fundamental issue for global sustainable development. Sustainable food production is the basis for food security and an effective approach to address global challenges such as climate change, land degradation, and ecological degradation. At present, there is a data gap in the monitoring and assessment of the sustainability of food production, and the supporting role of the Big Earth Data is increasingly prominent. This paper summarizes the current practice of Big Earth Data in support of sustainable food production, including the role of Earth observation technology in the monitoring of various elements of food production system, …

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Harnessing Big Earth Data To Facilitate Land Degradation Neutrality Goals—Practices And Prospects, Xiaosong Li, Qi Lu, Xiaoxia Jia Aug 2021

Harnessing Big Earth Data To Facilitate Land Degradation Neutrality Goals—Practices And Prospects, Xiaosong Li, Qi Lu, Xiaoxia Jia

Bulletin of Chinese Academy of Sciences (Chinese Version)

In 2015, the United Nations adopted the Transforming Our World:The 2030 Agenda for Sustainable Development, in which land degradation neutrality (LDN) is one of the important targets of the Sustainable Development Goal (SDG 15.3). However, due to varies indicative symptoms of land degradation in different climatic/geographical zones and land use types, the complexity of factors affecting land degradation or improvement, and the limits of spatial and temporal scope to define land degradation, for a long time, there was lack of common accepted methodology to identify land degradation, and short of key data set to establish reference baselines, and measure progress …

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Big Earth Data Supports Sustainable Cities And Communities: Progress And Challenges, Chunlin Huang, Zhongchang Sun, Huiping Jiang, Jianghao Wang, Penglong Wang, Jinhua Tao, Haimeng Liu, Nanjiang Liu Aug 2021

Big Earth Data Supports Sustainable Cities And Communities: Progress And Challenges, Chunlin Huang, Zhongchang Sun, Huiping Jiang, Jianghao Wang, Penglong Wang, Jinhua Tao, Haimeng Liu, Nanjiang Liu

Bulletin of Chinese Academy of Sciences (Chinese Version)

SDG 11-sustainable cities and communities is central to achieving all 17 SDGs. However, the lack of data is the main challenge for monitoring and assessing SDG 11 indicators. As an important aspect of technological innovation and big data, Big Earth Data can offer a new key to generate knowledge about the Earth, playing a major role in promoting sustainable development. In this research, we conducted many practical cases to monitor the progress of SDG indicators centered on urban sustainable development, and focused on 6 main themes about urban development, including urban housing, urban public transportation, urbanization, disaster prevention & mitigation, …

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Big Earth Data For Un Sustainable Development Goals: Climate Change And Action, Lei Huang, Gensuo Jia, Shibo Fang, Donghui Shangguan, Yonghong Hu, Zhaoming Zhang, Dailiang Peng Aug 2021

Big Earth Data For Un Sustainable Development Goals: Climate Change And Action, Lei Huang, Gensuo Jia, Shibo Fang, Donghui Shangguan, Yonghong Hu, Zhaoming Zhang, Dailiang Peng

Bulletin of Chinese Academy of Sciences (Chinese Version)

Climate change is becoming a major threat to human sustainable development in the coming decades. How to accurately and real-time monitor extreme weather events and disasters, and provide strong data and scientific support for climate change and disaster prevention and control, has become an urgent major scientific issue and decision-making proposition. The Sustainable Development Goals (SDGs) 13 Climate Action is to alleviate the threat of climate change and enhance human adaptation through the actions of countries. However, indicators of climate action lack the support of spatial data and information. The Big Earth Data is highly collaborative and integrated, which is …

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Big Earth Data Supports Synergies And Trade-Offs Of Sustainable Development Goals: Progress And Prospect, Jinwei Dong, Yu Chen, Yan Zhou, Jiadi Yin, Rui Zhao Aug 2021

Big Earth Data Supports Synergies And Trade-Offs Of Sustainable Development Goals: Progress And Prospect, Jinwei Dong, Yu Chen, Yan Zhou, Jiadi Yin, Rui Zhao

Bulletin of Chinese Academy of Sciences (Chinese Version)

The United Nations Sustainable Development Goals (SDGs) are an important guide for different countries and regions to achieve sustainable economic, social, and environmental developments. They include 17 goals and 169 specific targets. The interactions among the goals can be manifested as synergy or trade-off; that is, implementing one or more goals may positively or negatively affect other goals. At present, important progress has been made in the monitoring and evaluation of individual goals. However, our understanding of the synergies and trade-offs among multiple SDGs is still limited. Firstly, this paper describes the current progress in the synergy and trade-offs of …

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Stable Hydrogen Isotopes Of Aquatic-Emergent Versus Terrestrial Insects In Southern Ontario, Celina Y. Tang Aug 2021

Stable Hydrogen Isotopes Of Aquatic-Emergent Versus Terrestrial Insects In Southern Ontario, Celina Y. Tang

Undergraduate Student Research Internships Conference

Aquatic-emergent insects are vectors of both contaminants and nutrients, linking the aquatic system to the terrestrial system. Aquatic-emergent insects are high in omega-3 fatty acids that benefit terrestrial aerial insectivores, such as bats and birds. With aerial insectivores on a decline, a contributing factor could be a decrease in the quality of insects. We collected insects from lakeshore and inland locations in Southern Ontario. Insects sampled included bees, wasps, ants, beetles, caddisflies, craneflies, dragonflies, marchflies, mayflies, midges, other flies, and true bugs. Insects’ wings and powdered bodies were then analyzed for stable hydrogen isotopes (d2H) in order …

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Euler's De Serie Lambertina, Translated From Latin To English With Supplementary Notes, Sam Gallagher Aug 2021

Euler's De Serie Lambertina, Translated From Latin To English With Supplementary Notes, Sam Gallagher

Euleriana

Originally published in 1779, Euler's De Serie Lambertina provides one of the early examples of the Lambert W function, a special function used in the solution to certain transcendental equations. Following the work of Johann Heinrich Lambert in 1759, who discussed a series solution to the general polynomial in series, and then particularly the solution of the general trinomial, Euler describes a symmetric form of the trinomial and its series solution. Euler investigates the series' special cases and general properties, and its use in solving certain transcendental equations. He provides several proofs of the validity of the series expansion to …

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Translation Of Euler's Paper E421, Alexander Aycock Aug 2021

Translation Of Euler's Paper E421, Alexander Aycock

Euleriana

This is paper is the result of Euler’s findings on the Eulerian integral of second kind, i.e. the Γ-function: It summarises results and formulas on and properties of the integral in the title that Euler had obtained up to this point in his career and offers more elegant proofs of those before-mentioned results, formulas and properties. The results include a derivation of the integral in the title from an algebraic integral, the reflection formula for the Γ-function and finally a formula equivalent to the Gaußian multiplication formula for the Γ-function, expressed by Euler using mere integrals of algebraic functions.

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Euler And The Multiplication Formula For The Gamma Function, Alexander Aycock Aug 2021

Euler And The Multiplication Formula For The Gamma Function, Alexander Aycock

Euleriana

We show that an apparently overlooked result of Leonhard Euler (1707-1783) from [E421] is essentially equivalent to the general multiplication for- mula for the Γ-function that was proven by Carl Friedrich Gauss (1777-1855) in [Ga28].

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On The Rectilinear Motion Of Three Bodies Mutually Attracting Each Other, Sylvio R. Bistafa Aug 2021

On The Rectilinear Motion Of Three Bodies Mutually Attracting Each Other, Sylvio R. Bistafa

Euleriana

This is an annotated translation from Latin of E327 -- De motu rectilineo trium corporum se mutuo attrahentium (“On the rectilinear motion of three bodies mutually attracting each other”). In this publication, Euler considers three bodies lying on a straight line, which are attracted to each other by central forces inversely proportional to the square of their separation distance (inverse-square law). Here Euler finds that the parameter that controls the relative distances among the bodies is given by a quintic function.

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