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Articles 11941 - 11970 of 302419

Full-Text Articles in Physical Sciences and Mathematics

Electrochemical Hydrogen Gas Production And Carbon Dioxide Sequestration Via In Situ Formation Of Nickel (Ii) Tris-(Pyridinethiolate) Derivatives, Dayalis Sv. Brown Jul 2023

Electrochemical Hydrogen Gas Production And Carbon Dioxide Sequestration Via In Situ Formation Of Nickel (Ii) Tris-(Pyridinethiolate) Derivatives, Dayalis Sv. Brown

Dissertations and Theses

In the research presented, we use electrochemical techniques, such as cyclic voltammetry and controlled potential electrolysis, to study in situ formation of hydrogen evolution catalysts which also reduce carbon dioxide. Using pyridinethiol-based ligands and a nickel (II) precursor, both homo- and heteroleptic complexes were investigated as catalysts to produce alternative fuels while mitigating greenhouse gas emissions. Existing synthetic procedures to obtain these Ni(II) catalysts lead to low yields of the complexes and difficulties in crystallizing samples for further analysis, limiting sample size and restricting the number of studies. While current research is heavily focused on photochemically-driven experiments, given that solar …


Nickel Recovery From Low-Grade Laterites: Study Of Thermal Pre-Treatments To Improve The Efficiency Of The Hydrometallurgical Process, Johana Borda, Robinson Torres Jul 2023

Nickel Recovery From Low-Grade Laterites: Study Of Thermal Pre-Treatments To Improve The Efficiency Of The Hydrometallurgical Process, Johana Borda, Robinson Torres

Journal of Sustainable Mining

The processing of lower-grade laterites to obtain nickel has increased due to the gradual depletion of higher-grade sulphide ore reserves. However, the extraction from laterites has been limited because conventional technologies imply a considerable expense of energy or reagents. In this document, the effect of thermal pre-treatments on a laterite sample is demonstrated to improve nickel leaching under moderate conditions. The influence of agents such as coke, coal and NaCl in the heat treatment was also studied. With the results it is presumed that part of the nickel occluded in the goethite migrates to the iron oxides surface during the …


European Feedback On Post-Mining Seismicity, Isabelle Contrucci, Dalija Namjesnik, Peter Niemz, Paloma Primo, Andrzej Kotyrba, Grzegorz Mutke, Petr Konicek, Pascal Dominique, Tobias Rudolph, Stefan Möllerherm, Jannes Kinscher, Emmanuelle Klein, Simone Cesca Jul 2023

European Feedback On Post-Mining Seismicity, Isabelle Contrucci, Dalija Namjesnik, Peter Niemz, Paloma Primo, Andrzej Kotyrba, Grzegorz Mutke, Petr Konicek, Pascal Dominique, Tobias Rudolph, Stefan Möllerherm, Jannes Kinscher, Emmanuelle Klein, Simone Cesca

Journal of Sustainable Mining

Following the Paris Agreement adopted in 2015, Europe has committed to reducing its greenhouse gas emissions. In this context, the abandonment of coal as an energy source, both in terms of consumption and production, will lead to the closure of many mines in the years to come.

Mine closure guidelines to manage residual mining risks already exist in European countries. However, they do not include post-mining seismic risk management due to a lack of sufficient studies and knowledge on this subject. After mining closure, the flooding of the mining works leads to hydromechanical loading of the underground and, in the …


Analysis Of The Main Factor In The Implementation Of Open Defecation Free Using The Ahp Method, Vica Asrianti Dwiputri, Ova Candra Dewi Jul 2023

Analysis Of The Main Factor In The Implementation Of Open Defecation Free Using The Ahp Method, Vica Asrianti Dwiputri, Ova Candra Dewi

Smart City

Environmental sanitation refers to an environment's health status, including housing, sewage disposal, clean water supply, waste management, and other factors. Sustainable Development Goals 6 (SDG 6) ensures people access proper environmental sanitation. Based on the monitoring and evaluation results of Community-Based Total Sanitation (STBM) in 2022, it was found that 100% of open defecation had been stopped for Pillar 1 of STBM. This study aims to identify the factors that influence the success of implementing Open Defecation Free (ODF) programs in Depok City. There are two stages in this study to determine the priority factors that influence the success of …


Idempotent Completions Of Equivariant Matrix Factorization Categories, Michael K. Brown, Mark E. Walker Jul 2023

Idempotent Completions Of Equivariant Matrix Factorization Categories, Michael K. Brown, Mark E. Walker

Department of Mathematics: Faculty Publications

We prove that equivariant matrix factorization categories associated to henselian local hypersurface rings are idempotent complete, generalizing a result of Dyckerhoff in the non- equivariant case.


Artificial Intelligence Frameworks To Detect And Investigate The Pathophysiology Of Spaceflight Associated Neuro-Ocular Syndrome (Sans), Joshua Ong, Ethan Waisberg, Mouayad Masalkhi, Sharif Amit Kamran, Kemper Lowry, Prithul Sarker, Nasif Zaman, Phani Paladugu, Alireza Tavakkoli, Andrew G Lee Jul 2023

Artificial Intelligence Frameworks To Detect And Investigate The Pathophysiology Of Spaceflight Associated Neuro-Ocular Syndrome (Sans), Joshua Ong, Ethan Waisberg, Mouayad Masalkhi, Sharif Amit Kamran, Kemper Lowry, Prithul Sarker, Nasif Zaman, Phani Paladugu, Alireza Tavakkoli, Andrew G Lee

Student Papers, Posters & Projects

Spaceflight associated neuro-ocular syndrome (SANS) is a unique phenomenon that has been observed in astronauts who have undergone long-duration spaceflight (LDSF). The syndrome is characterized by distinct imaging and clinical findings including optic disc edema, hyperopic refractive shift, posterior globe flattening, and choroidal folds. SANS serves a large barrier to planetary spaceflight such as a mission to Mars and has been noted by the National Aeronautics and Space Administration (NASA) as a high risk based on its likelihood to occur and its severity to human health and mission performance. While it is a large barrier to future spaceflight, the underlying …


Change In Grassland Science: Implications For Training, Research And Grassland Societies, G. Lemaire, R. J. Wilkins, J. Hodgson Jul 2023

Change In Grassland Science: Implications For Training, Research And Grassland Societies, G. Lemaire, R. J. Wilkins, J. Hodgson

IGC Proceedings (1993-2023)

In most of the world the priority for production-oriented research has been succeeded by the need for grassland research to focus on systems which satisfy requirements relating to the stability and protection of land, water and atmospheric resources and to biodiversity, in addition to production efficiency. This dictates not only a new approach to research, but also new approaches for the organisation of research, the training and development of research scientists and the activities of Grassland Societies and associated organisations.


Citizen Scientists: Efforts By The Tri-Societies To Inject Science Into Us Policymaking, E. Bergfeld, K. Glasener Jul 2023

Citizen Scientists: Efforts By The Tri-Societies To Inject Science Into Us Policymaking, E. Bergfeld, K. Glasener

IGC Proceedings (1993-2023)

The Tri-Societies (American Society of Agronomy, Crop Science Society of America and Soil Science Society of America), the largest life science professional societies in the United States (US) dedicated to the agronomic, crop and soil sciences, encompass approximately 18,000 members globally and include approximately 14,000 certified professionals who are a direct conduit to the farming communities across the US. The Tri-Societies' US-based federal science policy programmes have been active for decades. There is a Washington, DC-based Director of Science Policy, Congressional Science Fellows (CSF) and Science Policy Interns.


Functionalized Go Nanoplatelets With Folic Acid As A Novel Material For Boosting Humidity Sensing Of Chitosan/Pva Nanocomposites For Active Food Packaging, Mohamed Morsy Jul 2023

Functionalized Go Nanoplatelets With Folic Acid As A Novel Material For Boosting Humidity Sensing Of Chitosan/Pva Nanocomposites For Active Food Packaging, Mohamed Morsy

Nanotechnology Research Centre

No abstract provided.


Self-Supervised Learning Application On Covid-19 Chest X- Ray Image Classification Using Masked Autoencoder, Xin Xing, Gongbo Liang, Chris Wang, Nathan Jacobs, Ai-Ling Lin Jul 2023

Self-Supervised Learning Application On Covid-19 Chest X- Ray Image Classification Using Masked Autoencoder, Xin Xing, Gongbo Liang, Chris Wang, Nathan Jacobs, Ai-Ling Lin

All Faculty Scholarship

The COVID-19 pandemic has underscored the urgent need for rapid and accurate diagnosis facilitated by artificial intelligence (AI), particularly in computer-aided diagnosis using medical imag- ing. However, this context presents two notable challenges: high diagnostic accuracy demand and limited availability of medical data for training AI models. To address these issues, we proposed the implementation of a Masked AutoEncoder (MAE), an innovative self-supervised learning approach, for classifying 2D Chest X-ray images. Our approach involved performing imaging reconstruction using a Vision Transformer (ViT) model as the feature encoder, paired with a custom-defined decoder. Additionally, we fine-tuned the pretrained ViT encoder using …


Foreword From Editor - 13th Edition, Yandi Andri Yatmo Jul 2023

Foreword From Editor - 13th Edition, Yandi Andri Yatmo

ASEAN Journal of Community Engagement

The current AJCE edition brings together meaningful discussions of community engagement programs as ways to disseminate various skills towards better society livelihood, focusing on product-making skills, women-led soft skills for families, and marketing skills. Elaborating on these objectives, this issue consists of four research-based articles and three case-based articles. The authors of this edition come from the background of economy, chemistry, community, psychology, and education—enabling diverse understanding of skills for the community and the means of how these skills can be acquired from different knowledge backgrounds.


Electron Scattering From 1-Methyl-5-Nitroimidazole: Cross-Sections Formodeling Electron Transport Through Potential Radiosensitizers, Ana I. Lozano, Lidia Álvarez, Adrián García-Abenza, Carlos Guerra, Fábris Kossoski, Jaime Rosado, Francisco Blanco, Juan Carlos Oller, Mahmudul Hasan, Martin Centurion, Thorsten Weber, Daniel S. Slaughter, Deepthy M. Mootheril, Alexander Dorn, Sarvesh Sarvesh, Paulo Limão-Vieira, Rafael Colmenares, Gustavo García Jul 2023

Electron Scattering From 1-Methyl-5-Nitroimidazole: Cross-Sections Formodeling Electron Transport Through Potential Radiosensitizers, Ana I. Lozano, Lidia Álvarez, Adrián García-Abenza, Carlos Guerra, Fábris Kossoski, Jaime Rosado, Francisco Blanco, Juan Carlos Oller, Mahmudul Hasan, Martin Centurion, Thorsten Weber, Daniel S. Slaughter, Deepthy M. Mootheril, Alexander Dorn, Sarvesh Sarvesh, Paulo Limão-Vieira, Rafael Colmenares, Gustavo García

Department of Physics and Astronomy: Faculty Publications

In this study, we present a complete set of electron scattering cross-sections from 1-Methyl-5- Nitroimidazole (1M5NI) molecules for impact energies ranging from 0.1 to 1000 eV. This information is relevant to evaluate the potential role of 1M5NI as a molecular radiosensitizers. The total electron scattering cross-sections (TCS) that we previously measured with a magnetically confined electron transmission apparatus were considered as the reference values for the present analysis. Elastic scattering cross-sections were calculated by means of two different schemes: The Schwinger multichannel (SMC) method for the lower energies (below 15 eV) and the independent atom model-based screening-corrected additivity rule with …


The Attempt And Operation Of Container Sharing Platform In The Yangtze River Delta: Efficient Transfer Of Empty Containers And Resources Sharing, Yifei Wei Jul 2023

The Attempt And Operation Of Container Sharing Platform In The Yangtze River Delta: Efficient Transfer Of Empty Containers And Resources Sharing, Yifei Wei

World Maritime University Dissertations

No abstract provided.


Towards Crisp‐Bc: 3tic Specification Framework For Blockchain Use‐Cases, Pouyan Jahanbin, Ravi S. Sharma, Stephen T. Wingreen, Nir Kshetri, Kim‐Kwang Raymond Choo Jul 2023

Towards Crisp‐Bc: 3tic Specification Framework For Blockchain Use‐Cases, Pouyan Jahanbin, Ravi S. Sharma, Stephen T. Wingreen, Nir Kshetri, Kim‐Kwang Raymond Choo

All Works

The application of Blockchain and augmented technologies such as IoT, AI, and Big Data platforms present a feasible approach for resolving the implementation challenges of trusted, decentralized platforms. This article proposes a DevOps framework for the specification of Blockchain use‐cases that enables evaluation, replication, and benchmarking. Specifically, it could be applied to specify the requirements and design characteristics of Blockchain applications in terms of key attributes such as: (i) transparency; (ii) traceability; (iii) tamper‐resistance; (iv) immutability; and (v) compliance. The article first introduces the design characteristics of Blockchain as a Platform and then examines successful use‐cases for its implementation using …


Investigating The Determinants Of Ordering Alternative Fueled New Vessels, Yuantao Chen Jul 2023

Investigating The Determinants Of Ordering Alternative Fueled New Vessels, Yuantao Chen

World Maritime University Dissertations

No abstract provided.


Accuracy Vs. Energy: An Assessment Of Bee Object Inference In Videos From On-Hive Video Loggers With Yolov3, Yolov4-Tiny, And Yolov7-Tiny, Vladimir A. Kulyukin, Aleksey V. Kulyukin Jul 2023

Accuracy Vs. Energy: An Assessment Of Bee Object Inference In Videos From On-Hive Video Loggers With Yolov3, Yolov4-Tiny, And Yolov7-Tiny, Vladimir A. Kulyukin, Aleksey V. Kulyukin

Computer Science Faculty and Staff Publications

A continuing trend in precision apiculture is to use computer vision methods to quantify characteristics of bee traffic in managed colonies at the hive's entrance. Since traffic at the hive's entrance is a contributing factor to the hive's productivity and health, we assessed the potential of three open-source convolutional network models, YOLOv3, YOLOv4-tiny, and YOLOv7-tiny, to quantify omnidirectional traffic in videos from on-hive video loggers on regular, unmodified one- and two-super Langstroth hives and compared their accuracies, energy efficacies, and operational energy footprints. We trained and tested the models with a 70/30 split on a dataset of 23,173 flying bees …


Study On The Construction Of Public Information Platform For International Multimodal Transport: A Case Study Of Shanghai, Yijie Chen Jul 2023

Study On The Construction Of Public Information Platform For International Multimodal Transport: A Case Study Of Shanghai, Yijie Chen

World Maritime University Dissertations

No abstract provided.


Study On The Improvement Of Production Efficiency Of Major Container Terminals In China, Sheng Lin Jul 2023

Study On The Improvement Of Production Efficiency Of Major Container Terminals In China, Sheng Lin

World Maritime University Dissertations

No abstract provided.


Study On Overcapacity Of Liner Shipping: On The Transpacific Routes, Yuxin Pu Jul 2023

Study On Overcapacity Of Liner Shipping: On The Transpacific Routes, Yuxin Pu

World Maritime University Dissertations

No abstract provided.


Analysis On The Fluctuations In Port Demand Caused By The Change In International Trade Of The Countries Along The 21st Century Maritime Silk Road: Take The Asean Countries For Example, Ziyi Shu Jul 2023

Analysis On The Fluctuations In Port Demand Caused By The Change In International Trade Of The Countries Along The 21st Century Maritime Silk Road: Take The Asean Countries For Example, Ziyi Shu

World Maritime University Dissertations

No abstract provided.


Research On Investment Risk And Decision Making In Dry Bulk Ships: Case Study Nijie Shipping World Limited, Mingyu Xu Jul 2023

Research On Investment Risk And Decision Making In Dry Bulk Ships: Case Study Nijie Shipping World Limited, Mingyu Xu

World Maritime University Dissertations

No abstract provided.


Study On Port Service Capacity Along The 21st Century Maritime Silk Road: Taking Container Ports As An Example, Rujin Fu Jul 2023

Study On Port Service Capacity Along The 21st Century Maritime Silk Road: Taking Container Ports As An Example, Rujin Fu

World Maritime University Dissertations

No abstract provided.


Study On Container Linerroute Optimization Of Southeast Asia Route Of M Shipping Company, Lefan Liu Jul 2023

Study On Container Linerroute Optimization Of Southeast Asia Route Of M Shipping Company, Lefan Liu

World Maritime University Dissertations

No abstract provided.


The Loneliest Galaxies In The Universe: A Gama And Galaxy Zoo Study On Void Galaxy Morphology, Lori E. Porter, Benne Holwerda, Sandor Kruk, Maritza Lara-López, Kevin A. Pimbblet, Christopher P A Henry, Sarah Casura, Lee S. Kelvin Jul 2023

The Loneliest Galaxies In The Universe: A Gama And Galaxy Zoo Study On Void Galaxy Morphology, Lori E. Porter, Benne Holwerda, Sandor Kruk, Maritza Lara-López, Kevin A. Pimbblet, Christopher P A Henry, Sarah Casura, Lee S. Kelvin

Faculty and Staff Scholarship

The large-scale structure of the Universe is comprised of galaxy filaments, tendrils, and voids. The majority of the Universe’s volume is taken up by these voids, which exist as underdense, but not empty, regions. The galaxies found inside these voids are expected to be some of the most isolated objects in the Universe. This study, using the Galaxy and Mass Assembly (GAMA) and Galaxy Zoo surveys, aims to investigate basic physical properties and morphology of void galaxies versus field (filament and tendril) galaxies. We use void galaxies with stellar masses (⁠M∗" role="presentation" style="box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; …


Watermark Hiding In Hdr Image Based On Visual Saliency And Tucker Decomposition, Roa'a M. Al-Airaji, Ibtisam A. Aljazaery, Haider Th. Salim Alrikabi Jul 2023

Watermark Hiding In Hdr Image Based On Visual Saliency And Tucker Decomposition, Roa'a M. Al-Airaji, Ibtisam A. Aljazaery, Haider Th. Salim Alrikabi

Karbala International Journal of Modern Science

Recently, great attention has been paid to high dynamic range (HDR) images because of their richly detailed and high dynamic range of intensity. The need for pre-processing of the HDR image format with tone mapping (TM) operators makes it unique; the TM operators are provided on display with a low dynamic range (LDR). On the other hand, TM can be regarded as an inevitable attack when protecting HDR image ownership is considered. An adaptive approach for concealing watermarks based on visual saliency and Tucker decomposition has been presented in this article. In the first step, three feature maps were produced …


Light Alters Leaf Breakdown Rates And Metabolic Activity In Anthropogenically Impacted Nebraska Streams, William Reilly Farrell Jul 2023

Light Alters Leaf Breakdown Rates And Metabolic Activity In Anthropogenically Impacted Nebraska Streams, William Reilly Farrell

School of Natural Resources: Dissertations, Theses, and Student Research

Algal growth influences carbon breakdown rates in aquatic ecosystems; however, the magnitude and direction of these effects differ based on ecosystem context. To explore algal priming effects on decomposition in anthropogenically impacted ecosystems, I conducted light manipulation experiments in three streams, each surrounded by different land uses (i.e., predominantly urban, row crop, or concentrated animal feeding operation) across Nebraska. I measured leaf breakdown rates, metabolic activity, fungal and algal biomass, and leaf percent carbon (C) and phosphorus (P) to assess the effect of light differences. These streams were impacted by sedimentation and turbidity over the course of the leaf incubation. …


Pronghorn Survival And Resource Selection In Western Nebraska's Agriculturally Dominated Landscape, Katie Piecora Jul 2023

Pronghorn Survival And Resource Selection In Western Nebraska's Agriculturally Dominated Landscape, Katie Piecora

School of Natural Resources: Dissertations, Theses, and Student Research

Nebraska’s pronghorn population has been stable over the last decade, yet their presence on the landscape remains a contentious subject amongst private landowners. Conversion of grassland for crop production and increased anthropogenic activity has drastically altered pronghorn behavior throughout their current range, however basic ecology and resource use by pronghorn in Nebraska remains poorly understood. Establishing baseline population metrics and seasonal patterns of resource use for this population at the eastern periphery of the species range is critical to guide management actions. We deployed GPS collars on 110 adult pronghorn to quantify survival, mortality risk, and seasonal resource selection in …


Propagation Of Spatiotemporal Optical Vortex Beams In Linear, Second-Order Dispersive Media, Milo W. Hyde Iv, Miguel A. Porras Jul 2023

Propagation Of Spatiotemporal Optical Vortex Beams In Linear, Second-Order Dispersive Media, Milo W. Hyde Iv, Miguel A. Porras

Faculty Publications

In this paper, we study the behaviors of spatiotemporal optical vortex (STOV) beams propagating in linear dispersive media. Starting with the Fresnel diffraction integral, we derive a closed-form expression for the STOV field at any propagation distance z in a general second-order dispersive medium. We compare our general result to special cases published in the literature and examine the characteristics of higher-order STOV beams propagating in dispersive materials by varying parameters of the medium and source-plane STOV field. We validate our analysis by comparing theoretical predictions to numerical computations of a higher-order STOV beam propagating through fused silica, where we …


Annotation Of Non-Model Species’ Genomes, Taiya Jarva Jul 2023

Annotation Of Non-Model Species’ Genomes, Taiya Jarva

Master's Theses

The innovations in high throughput sequencing technologies in recent decades has allowed unprecedented examination and characterization of the genetic make-up of both model and non-model species, which has led to a surge in the use of genomics in fields which were previously considered unfeasible. These advances have greatly expanded the realm of possibilities in the fields of ecology and conservation. It is now possible to the identification of large cohorts of genetic markers, including single nucleotide polymorphisms (SNPs) and larger structural variants, as well as signatures of selection and local adaptation. Markers can be used to identify species, define population …


Critical Factors And Individual Decision Making In Earthquake And Tsunami Preparedness Among Coastal Communities Inoregon U.S.A., Shelley Olds Jul 2023

Critical Factors And Individual Decision Making In Earthquake And Tsunami Preparedness Among Coastal Communities Inoregon U.S.A., Shelley Olds

School of Natural Resources: Dissertations, Theses, and Student Research

Earthquakes and tsunamis are natural hazards that cause considerable loss of life, destruction of property and infrastructure, and economic damage. Preparedness is critical in regions of significant earthquake and tsunami risk. A key challenge for organizations that manage hazard preparedness and response is mobilizing earthquake preparedness among individuals and families. This dissertation provides an examination of individual earthquake and tsunami preparedness from both a global and regional perspective. It comprises two publications that explore various aspects of disaster preparedness.

Chapter One provides an overview of global seismic and tsunami hazards, along with potential impacts, and addresses the challenges in promoting …