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Articles 25411 - 25440 of 291756

Full-Text Articles in Physical Sciences and Mathematics

Technological Challenges And Development Directions Of Ecological Security Barrier Construction In Yun-Gui-Chuan-Yu Region, Peng Cui, Yongping Yang, Genxu Wang, Bo Zhu, Xuyang Lu, Geng Sun, Xiaoyong Bai, Sirui Zhang, Yonggang Ge, Jiao Wang Jun 2024

Technological Challenges And Development Directions Of Ecological Security Barrier Construction In Yun-Gui-Chuan-Yu Region, Peng Cui, Yongping Yang, Genxu Wang, Bo Zhu, Xuyang Lu, Geng Sun, Xiaoyong Bai, Sirui Zhang, Yonggang Ge, Jiao Wang

Bulletin of Chinese Academy of Sciences (Chinese Version)

The Yun-Gui-Chuan-Yu Ecological Security Barrier is situated in Southwest China, encompassing the provinces of Sichuan, Chongqing, Guizhou, and Yunnan. It serves as a vital water source conservation area and a core zone for biodiversity protection for the Yangtze, Yellow, and Pearl River basins, playing a crucial role in China’s national ecological security. Since the 18th National Congress of Communist Party of China, under the guidance of Xi Jinping’s Thought on Ecological Civilization, the region has made significant strides in water resource protection, soil erosion and mountain disaster control, biodiversity conservation, and ecosystem restoration, resulting in noticeable improvements in environmental quality …

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Science And Technology Support Ecosystem Protection And Restoration In Western China To Ensure Ecological Security Of The Country, Zhiyun Ouyang, Lingqiao Kong, Binbin Huang, Weihua Xu, Bojie Fu Jun 2024

Science And Technology Support Ecosystem Protection And Restoration In Western China To Ensure Ecological Security Of The Country, Zhiyun Ouyang, Lingqiao Kong, Binbin Huang, Weihua Xu, Bojie Fu

Bulletin of Chinese Academy of Sciences (Chinese Version)

The western China has developed the Earth’s unique ecosystems, which is not only the main provider of ecosystem products and the important barrier of ecological security in China, but also the key area of ecosystem protection and restoration because of its ecological fragility. In recent years, a series of the major protection and restoration projects of ecosystems have been implemented, and have achieved remarkable progress in western China. Nevertheless, due to its ecosystem instability and unsustainability, ecological security is still facing severe challenges in western China. This study first analyzes the crucial roles of the western region as an ecological …

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Science And Technology Support For Climate Change Mitigation And Adaptation Over Western China, Huijun Wang, Huopo Chen Jun 2024

Science And Technology Support For Climate Change Mitigation And Adaptation Over Western China, Huijun Wang, Huopo Chen

Bulletin of Chinese Academy of Sciences (Chinese Version)

In the context of accelerating global warming, the western China has experienced intensified climate extremes, with frequent occurrences of meteorological, hydrological, and ecological disasters. The unpredictability of these events has increased, posing significant challenges to disaster prevention and mitigation as well as sustainable development in these areas. In this context, this study, based on a scientific assessment of the facts and risks of climate change in the western China, has identified several fundamental, critical, and strategic scientific and technological tasks to support the development of the western China in the field of climate change. Corresponding suggestions and measures are also …

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Biodiversity Conservation In Western China With Scientific And Technological Support: Current Status, Challenges, And Suggestions, Fuwen Wei, Hang Sun, Jiaojun Zhu, Baoguo Li, Gexia Qiao, Shilong Chen, Jiang Zhu, Xiaoge Ping Jun 2024

Biodiversity Conservation In Western China With Scientific And Technological Support: Current Status, Challenges, And Suggestions, Fuwen Wei, Hang Sun, Jiaojun Zhu, Baoguo Li, Gexia Qiao, Shilong Chen, Jiang Zhu, Xiaoge Ping

Bulletin of Chinese Academy of Sciences (Chinese Version)

As a megadiverse country, China has made significant progress in biodiversity conservation in recent years. The western region is a critical area for biodiversity conservation in China, boasting rich species resources and a high proportion of endemic species. However, its ecosystems are fragile and vulnerable to the impacts of multiple factors like climate change and human activities. Scientific and technological support has played a vital supporting role in biodiversity conservation, providing comprehensive support from monitoring and assessment to restoration and decision-making through biodiversity surveys, scientific research, and the establishment of monitoring networks. Nevertheless, challenges remain, including gaps in taxa and …

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Exploration On Path Of Ecological Protection And Economic Development In Qilian Mountain National Park Region, Xinmiao Tian, Qi Feng Jun 2024

Exploration On Path Of Ecological Protection And Economic Development In Qilian Mountain National Park Region, Xinmiao Tian, Qi Feng

Bulletin of Chinese Academy of Sciences (Chinese Version)

National parks are a kind of special protected areas established under the leadership of the government with the core objective of protecting the integrity of natural ecosystems and biodiversity, which emphasizes the balance between human activities and nature protection in order to achieve sustainable coexistence of human being and nature. The construction of a system of nature reserves with national parks as the core is a major breakthrough progress in the institutional framework of China’s ecological civilization, and a key area for promoting the construction of Beautiful China and realizing the modernization of harmonious coexistence of human being and nature. …

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Towards 5th World Congress Of Biosphere Reserves: Opportunities And Recommended Actions For China, Yijie Xian, Qiang Fang, Ning Liu, Xiangjun Chen, Yan Zhuang, Ding Wang, Qunli Han Jun 2024

Towards 5th World Congress Of Biosphere Reserves: Opportunities And Recommended Actions For China, Yijie Xian, Qiang Fang, Ning Liu, Xiangjun Chen, Yan Zhuang, Ding Wang, Qunli Han

Bulletin of Chinese Academy of Sciences (Chinese Version)

The holding of important international conferences in science and technology can generally bring multiple benefits for the host countries, such as developing strategy in the area of international cooperation. One example comes from the 5th World Congress of Biosphere Reserves due to be held in Hangzhou, China from September 22–27, 2025. This study summarizes the history of previous congresses and the system of Man and the Biosphere Programme (MAB) in which the congresses are located. Significance of the 5th Congress can be found as increasing the global engagement and international influence of MAB, and advancing the achievement of the United …

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Successful Management Of Chromoblastomycosis Utilizing Conventional Antifungal Agents And Imiquimod Therapy, Jinjin Zheng, Shougang Liu, Zhenmou Xie, Yangxia Chen, Liyan Xi, Hongfang Liu, Yinghui Liu Jun 2024

Successful Management Of Chromoblastomycosis Utilizing Conventional Antifungal Agents And Imiquimod Therapy, Jinjin Zheng, Shougang Liu, Zhenmou Xie, Yangxia Chen, Liyan Xi, Hongfang Liu, Yinghui Liu

Faculty, Staff and Student Publications

Chromoblastomycosis (CBM), a chronic fungal infection affecting the skin and subcutaneous tissues, is predominantly caused by dematiaceous fungi in tropical and subtropical areas. Characteristically, CBM presents as plaques and nodules, often leading to scarring post-healing. Besides traditional diagnostic methods such as fungal microscopy, culture, and histopathology, dermatoscopy and reflectance confocal microscopy can aid in diagnosis. The treatment of CBM is an extended and protracted process. Imiquimod, acting as an immune response modifier, boosts the host's immune response against CBM, and controls scar hyperplasia, thereby reducing the treatment duration. We present a case of CBM in Guangdong with characteristic reflectance confocal …

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2024 June 20 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University Jun 2024

2024 June 20 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

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The Osteological Neutral Pose Of The Neck Of An Apatosaurine Sauropod Based On Virtual And Physical Models, Colin Don Boisvert Jun 2024

The Osteological Neutral Pose Of The Neck Of An Apatosaurine Sauropod Based On Virtual And Physical Models, Colin Don Boisvert

Theses and Dissertations

An array of sauropod taxa coexisted in Late Jurassic North America. How so many giant genera coexisted without competing for food is puzzling considering their potential metabolic requirements. One aspect of this question is neck posture, which has been much contested, both in terms of the intrinsic curvature of the neck and the resultant elevation of the head. Neck curvature is characterized by the Osteological Neutral Pose (ONP), wherein the intervertebral joints are in an undeflected state. This pose is crucial to understanding neck posture. The articulated series of presacral vertebrae 2-19 of an exceptionally well-preserved apatosaurine, BYU 18531, are …

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Evaluation Of An Autonomous Acoustic Surveying Technique For Grassland Bird Communities In Nebraska, Grace E. Schuster, Leroy J. Walston, Andrew R. Little Jun 2024

Evaluation Of An Autonomous Acoustic Surveying Technique For Grassland Bird Communities In Nebraska, Grace E. Schuster, Leroy J. Walston, Andrew R. Little

School of Natural Resources: Faculty Publications

Monitoring trends in wildlife communities is integral to making informed land management decisions and applying conservation strategies. Birds inhabit most niches in every environment and because of this they are widely accepted as an indicator species for environmental health. Traditionally, point counts are the common method to survey bird populations, however, passive acoustic monitoring approaches using autonomous recording units have been shown to be cost-effective alternatives to point count surveys. Advancements in automatic acoustic classification technologies, such as BirdNET, can aid in these efforts by quickly processing large volumes of acoustic recordings to identify bird species. While the utility of …

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Primary Care Payment Models And Avoidable Hospitalizations In Ontario, Canada: A Multivalued Treatment Effects Analysis., Nibene Habib Somé, Rose Anne Devlin, Nirav Mehta, Sisira Sarma Jun 2024

Primary Care Payment Models And Avoidable Hospitalizations In Ontario, Canada: A Multivalued Treatment Effects Analysis., Nibene Habib Somé, Rose Anne Devlin, Nirav Mehta, Sisira Sarma

Epidemiology and Biostatistics Publications

Improving access to primary care physicians' services may help reduce hospitalizations due to Ambulatory Care Sensitive Conditions (ACSCs). Ontario, Canada's most populous province, introduced blended payment models for primary care physicians in the early- to mid-2000s to increase access to primary care, preventive care, and better chronic disease management. We study the impact of payment models on avoidable hospitalizations due to two incentivized ACSCs (diabetes and congestive heart failure) and two non-incentivized ACSCs (angina and asthma). The data for our study came from health administrative data on practicing primary care physicians in Ontario between 2006 and 2015. We employ a …

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Implementing 1.5 Millimeter Internal Diameter Columns And A Portable Capillary Column Instrument Into Monoclonal Antibody Analytical Workflows, Benjamin Libert Jun 2024

Implementing 1.5 Millimeter Internal Diameter Columns And A Portable Capillary Column Instrument Into Monoclonal Antibody Analytical Workflows, Benjamin Libert

Theses and Dissertations

Using 1.5 mm inner diameter (i.d.) columns to bridge the gap between routinely used 2.1 mm i.d. columns and capillary bore columns allows for a sequential but significant increase in performance without the need for specialized equipment associated with very low dispersion liquid chromatography (LC) systems. These 1.5 mm i.d. columns balance an increase in sensitivity compared to 2.1 mm i.d. columns (theoretically doubling the time-domain peak area in mass sensitive detectors for the same mass load), while mitigating the efficiency losses due to extra-column dispersion effects that are commonly observed with 1.0 mm i.d. columns. Here, the use of …

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Effects Of Differing Radiation Methods On Charge Transport In Polymers, Zachary Gibson, Jr Dennison, Virginie Griseri Jun 2024

Effects Of Differing Radiation Methods On Charge Transport In Polymers, Zachary Gibson, Jr Dennison, Virginie Griseri

Presentations

The mitigation of deleterious arcing and sparking onboard spacecraft depends upon a thorough understanding of the electrical properties of the materials involved. This includes not only understanding steady-state parameters such as dark conductivity, but responses to the space environment as well. For example, radiation-induced conductivity drastically changes the conductivity of a material due to the presence of radiation. However, this change in conductivity diminishes away once the radiation is no longer present. There may also be permanent changes, or aging, in the material properties. The physical processes of aging can be complicated and are often difficult to model. Therefore, empirical …

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Thermal Effects On The Voc-Sensitive Polydimethylsiloxane Holographic Gratings, Aleksandra Hernik, Faolan Radford Mcgovern, Patrick Iftime, Izabela Naydenova Jun 2024

Thermal Effects On The Voc-Sensitive Polydimethylsiloxane Holographic Gratings, Aleksandra Hernik, Faolan Radford Mcgovern, Patrick Iftime, Izabela Naydenova

Conference Papers

The imperative for monitoring volatile organic compounds (VOCs) emerges from their harmful impact on human health when inhaled excessively over a long term. Polydimethylsiloxane (PDMS), valued for its transparency and excellent flexibility, has already been demonstrated as a promising biocompatible and cost-effective transducer for optical VOCs sensing. Moreover, it facilitates further functionalisation with adsorbing materials to enhance sensitivity and selectivity for specific VOCs detection. We fabricated and examined PDMS-based surface diffraction gratings after exposure to selected VOCs, demonstrating different response for polar and non-polar molecules. Investigated gratings were prepared by replicating sinusoidal surface relief structures inscribed in acrylamide photopolymer using …

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Reinforcement Learning For Robotic Tasks: Analyzing And Understanding The Learning Process Using Explainable Artificial Intelligence Methods, Brian J. Campana Jun 2024

Reinforcement Learning For Robotic Tasks: Analyzing And Understanding The Learning Process Using Explainable Artificial Intelligence Methods, Brian J. Campana

Theses and Dissertations

As deep reinforcement learning (RL) models gain traction across more industries, there is a growing need for reliable agent-explanation techniques to understand these models. Researchers have developed explainable artificial intelligence (XAI) methods to help understand these 'black boxes'. While these models have been tested on many supervised learning tasks, there is a lack of examination of how these well these methods can explain hard reinforcement learning problems like robotic control. The sequential nature of learning RL policies and testing episodes create fundamentally different policies over time compared to more traditional supervised learning models. In this thesis, two important questions are …

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Fspde: A Full Stack Plausibly Deniable Encryption System For Mobile Devices, Jinghui Liao, Niusen Chen, Lichen Xia, Bo Chen, Weisong Shi Jun 2024

Fspde: A Full Stack Plausibly Deniable Encryption System For Mobile Devices, Jinghui Liao, Niusen Chen, Lichen Xia, Bo Chen, Weisong Shi

Michigan Tech Publications

In today’s digital landscape, the ubiquity of mobile devices underscores the urgent need for stringent security protocols in both data transmission and storage. Plausibly deniable encryption (PDE) stands out as a pivotal solution, particularly in jurisdictions marked by rigorous regulations or increased vulnerabilities of personal data. However, the existing PDE systems for mobile platforms have evident limitations. These include vulnerabilities to multi-snapshot attacks over RAM and flash memory, an undue dependence on non-secure operating systems, traceable PDE entry point, and a conspicuous PDE application prone to reverse engineering. To address these limitations, we have introduced FSPDE, the first Full-Stack mobile …

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Complex Segment Linkage Along The Sevier Normal Fault, Southwestern Utah, Benjamin Surpless, Wanda J. Taylor, Ilsa M. Schiefelbein Kerscher Jun 2024

Complex Segment Linkage Along The Sevier Normal Fault, Southwestern Utah, Benjamin Surpless, Wanda J. Taylor, Ilsa M. Schiefelbein Kerscher

Earth and Environmental Geosciences Faculty Research

Major normal fault systems are composed of segments that link as displacement accumulates, with linkage zone characteristics that reveal fault zone evolution. The steeply west-dipping Sevier fault zone in southwestern Utah, displays a complex fault network that developed between two long (>10 km), en echelon segments near the town of Orderville. Geologic map data and cross-sections of the transfer zone between the Mt. Carmel segment in the south and the Spencer Bench segment in the north reveal more than ten normal faults and four relay ramps displaying a range of geometries, including two relay ramps that display ramp-parallel folds. …

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The Glucosylamine Oxidation Pathway Of Vitamin C Recycling, James M. Hempe, Daniel S. Hsia, Arthur Hagar, Larry Byers Jun 2024

The Glucosylamine Oxidation Pathway Of Vitamin C Recycling, James M. Hempe, Daniel S. Hsia, Arthur Hagar, Larry Byers

School of Medicine Faculty Publications

The proposed glucosylamine oxidation pathway (GOP) is a two-step, intraerythrocyte, thermodynamically favorable nonenzymatic reaction that first binds glucose to the N-terminal valine of beta globin (βVal1) to form a closed-chain glucosylamine that can spontaneously reduce oxidized vitamin C to its antioxidant form. This review summarizes analytical, biochemical and clinical research supporting the existence of the GOP and the surprising hypothesis that βVal1 glucosylamine is a reducing agent that works cooperatively with reduced glutathione to dynamically regulate vitamin C recycling during naturally occurring periods of transiently or chronically elevated blood glucose and oxidant production. Rationale for the existence of the GOP …

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Butte Priority Soils Operable Unit (Bpsou) Draft Final Insufficiently Reclaimed Sites Field Sampling Plan (Fsp) Bres No. 181 – Mountain Con-3 Dump, Mike Mcanulty Jun 2024

Butte Priority Soils Operable Unit (Bpsou) Draft Final Insufficiently Reclaimed Sites Field Sampling Plan (Fsp) Bres No. 181 – Mountain Con-3 Dump, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

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Synthetic Assembly Of Antibacterial Agents And Metal Chelating Ligands, Zachary Joseph Liveris Jun 2024

Synthetic Assembly Of Antibacterial Agents And Metal Chelating Ligands, Zachary Joseph Liveris

Dissertations

The exploitation of chemical synthesis exemplifies the notion of bridging both innovation and curiosity for the strategic assembly of sophisticated molecular infrastructures. By exerting this continuously evolving and versatile tool, synthesis has been applied in the development and influence of a myriad of ligands, biological probes, and persists to direct pharmaceutical innovation and modern medicine alike. Since pathogenic multidrug-resistant (MDR) microbial strains remain to be a persistent threat to both clinical healthcare and society, the need to develop selective and efficacious antibacterial agents that can impede microbe pathogenicity and regulate cellular mortality is paramount. In contrast to pharmaceutical development, organic …

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Ct-To-Mri Synthesis For High-Dose-Rate Brachytherapy Treatment Planning, Rachel Nicole Gordon Jun 2024

Ct-To-Mri Synthesis For High-Dose-Rate Brachytherapy Treatment Planning, Rachel Nicole Gordon

Master's Theses

High-dose-rate (HDR) brachytherapy is a radiation treatment modality that places radioactive sources directly in cancerous regions. Radiation treatment planning for HDR prostate brachytherapy utilizes both CT and MRI to visualize the path of the radioactive source and the prostate gland, respectively. In this work, we propose GAN-CM, a method for conditional CT-to-MRI translation that is based on Generative Adversarial Networks (GANs). The proposed method uses the typical generator-discriminator design of GANs with a modified generator that incorporates semantic masks obtained from the domain image. The use of semantic masks allows GAN-CM to better capture the anatomical details and tissue characteristics …

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Impact Of Covid-19 On Disaggregate Consumption And Online Retail Sales: Evidence From The Usa, Gulzar Ahmed, Olcay Akman Jun 2024

Impact Of Covid-19 On Disaggregate Consumption And Online Retail Sales: Evidence From The Usa, Gulzar Ahmed, Olcay Akman

Spora: A Journal of Biomathematics

This study applies the difference-in-difference technique to analyze the consumption pattern during COVID-19 against pre-COVID-19 years. We analyze the online retail sales before and after COVID-19 using time series and linear regression models. Time series intervention analysis results suggest that COVID-19 has caused a statistically significant change in the mean level of online retail sales share in e-commerce. Using a difference-in-difference approach, we find a 4% decrease in aggregate consumption from March to December 2020 compared to the benchmark period although statistically insignificant. Further, using a fixed effects model with time dummies, we find a nearly 8% significant decrease in …

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Risk Of Climate Damage In The Mountain West, 2024, Taylor Volk, Isabelle G. Graham, Ivan Sun, Zachary Billot, Caitlin J. Saladino, William E. Brown Jr. Jun 2024

Risk Of Climate Damage In The Mountain West, 2024, Taylor Volk, Isabelle G. Graham, Ivan Sun, Zachary Billot, Caitlin J. Saladino, William E. Brown Jr.

Environment

This fact sheet examines 2024 data on the estimated annual cost per person of damage to infrastructure, agriculture, and population from climate related disasters for the five Mountain West states of Arizona, Colorado, Nevada, New Mexico, and Utah. The original report, “States at Greatest Risk of Climate Damage - 2024 Study,” by Jaclyn DeJohn and published by SmartAsset, includes data on climate disaster risk for all 50 states.

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Turning Trash Into Treasure: Using Old Optical Spectrometers As Learning Tools In Instrumental Analysis, Ken Overway Jun 2024

Turning Trash Into Treasure: Using Old Optical Spectrometers As Learning Tools In Instrumental Analysis, Ken Overway

Chemistry Faculty Scholarship

Chemical instrumentation is complex and expensive. When an instrument becomes nonfunctional, its pedagogical value remains despite its inability to make measurements. This work presents a laboratory experiment which gives new purpose to old optical spectrometers while building knowledge and confidence of students in their understanding of chemical instrumentation. Students are given a guided tour of spectroscopic instruments, starting from the simplest, and are asked to identify components and draw the optical path of each instrument. Allowing students to look inside of decommissioned instruments gives students a chance to see the differences and similarities of optical spectrometers while reinforcing the form …

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Investigation Of The Uv-Resistance Of Photopolymerisable Glass For Space Applications, Luca Sorridente, Tatsiana Mikulchyk, Izabela Naydenova, Kevin Murphy Jun 2024

Investigation Of The Uv-Resistance Of Photopolymerisable Glass For Space Applications, Luca Sorridente, Tatsiana Mikulchyk, Izabela Naydenova, Kevin Murphy

Articles

The progress of space based scientific research leads to an increasing demand for more efficient and less bulky instruments. Conventional refractive elements make up a critical part of many optical instruments launched into space; however, they can be bulky and heavy. Holographic optical elements are an efficient alternative to replace the conventional optical elements as they are lightweight and can be miniaturized. Current materials typically used for volume holographic optical elements are not robust enough for use in space environment. Recently a promising photopolymerisable glass has been developed using a sol-gel technique, which can provide dry layers suitable for holographic …

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Thz Radar Observations Of Hydrometeors In A Spray Chamber, Zeen Zhu, Fan Yang, Edward Luke, Elise Rosky, Katia Lamer, Pavlos Kollias Jun 2024

Thz Radar Observations Of Hydrometeors In A Spray Chamber, Zeen Zhu, Fan Yang, Edward Luke, Elise Rosky, Katia Lamer, Pavlos Kollias

Michigan Tech Publications

A THz radar, with its wide bandwidth, is capable of high-resolution imaging down to the centimeter scale. In this study, a THz radar is applied to detect hydrometeors generated in a spray chamber. The observed backscattering signals show fluctuations at centimeter scales, indicating various hydrometeor distribution patterns along the radar beam. A co-located High-Speed Imaging (HSI) sensor is used to measure the Drop Size Distributions (DSD) in the spray chamber. The radar sampling beam is well aligned with the HSI probes, allowing an objective comparison between the remote sensing and in situ observations. In this study, the observed radar power …

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Specification, Enforcement, And Measurement Of Integrity Policies, Kevin Dennis Jun 2024

Specification, Enforcement, And Measurement Of Integrity Policies, Kevin Dennis

USF Tampa Graduate Theses and Dissertations

The first step to improving an organization's security posture is to define the organization's security goals. At a technical level, these goals are expressed as security policies. Security policies are predicates over programs, that return true or false if the program adheres to the policy. Defining these policies correctly is thus essential to ensuring the overarching security goals are met, but it is often quite difficult to translate human-oriented goals into their technical policy counterparts. In addition, these policies must be specified so that they are enforceable while minimizing false positives and false negatives. Integrity policies, which specify how data …

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Extreme Value Statistics Analysis Of Process Defects In Additive Manufacturing Materials, Ayorinde E. Olatunde, Kristen Hernandez, Austin Ngo, Arafath Nihar, Thomas G. Ciardi, Rachel Yamamoto, Pawan K. Tripathi, Roger H. French, John J. Lewandowski, Anirban Mondal Jun 2024

Extreme Value Statistics Analysis Of Process Defects In Additive Manufacturing Materials, Ayorinde E. Olatunde, Kristen Hernandez, Austin Ngo, Arafath Nihar, Thomas G. Ciardi, Rachel Yamamoto, Pawan K. Tripathi, Roger H. French, John J. Lewandowski, Anirban Mondal

Faculty Scholarship

Fatigue and fracture studies focused on process defects that occur in Additive Manufacturing (AM) materials have shown that defect populations possess features which are better measured with extreme value statistics (EVS). In AM alloys, defect occurrences increase with material volume. This situation facilitates the need to model process defects in the path of fatigue crack growth with suitable statistical tools, such as EVS, which is more cost-effective when compared to destructive experiments. The application of EVS on defect space features helps determine the difference in defects present on fracture surfaces. As the fatigue quality of any material depends on its …

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Procedural Pre-Training For Visual Recognition, Connor S. Anderson Jun 2024

Procedural Pre-Training For Visual Recognition, Connor S. Anderson

Theses and Dissertations

Deep learning models can perform many tasks very capably, provided they are trained correctly. Usually, this requires a large amount of data. Pre-training refers to a process of creating a strong initial model by first training it on a large-scale dataset. Such a model can then be adapted to many different tasks, while only requiring a comparatively small amount of task-specific training data. Pre-training is the standard approach in most computer vision scenarios, but it's not without drawbacks. Aside from the cost and effort involved in collecting large pre-training datasets, such data may also contain unwanted biases, violations of privacy, …

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Photopolymer Material Durability And Safety In Holographic Diffusers For Visual Applications, Matthew Hellis, Alan Casey, Edoardo Splendi, Suzanne Martin, Matthew Sheehan, Kevin Murphy Jun 2024

Photopolymer Material Durability And Safety In Holographic Diffusers For Visual Applications, Matthew Hellis, Alan Casey, Edoardo Splendi, Suzanne Martin, Matthew Sheehan, Kevin Murphy

Articles

This study introduces novel holographic diffuser applications employing acrylamide- or diacetone acrylamide-based photopolymers, patterned within the volume on a micron scale by a single-beam holographic recording process. These diffusers have previously been presented as potential treatments for amblyopia and diplopia. This work has now been extended to spectrometric analysis to determine their properties under broadband light. Diffusive elements with higher diffusion efficiencies exhibited a marginal reduction (< 5%) in diffusion efficiency across most of the visible spectrum. Given the intended application of these holographic diffusers, cytotoxicity assessments were also performed. This is significant as there is a difference in toxicity between the crystalline acrylamide (classified as a category 3 material) and diacetone acrylamide (classified as a category 4 material). The findings indicated substantially lower toxicity in holograms produced with diacetone acrylamide-based photopolymer. The accelerated ageing of both formulations of holographic diffusers indicated that the acrylamide-based holographic diffusers did not reduce efficacy in the 292 days of ageing. The diacetone acrylamide-based holographic diffusers exhibited reduced efficacy by day 182. Despite this, both formulations have been shown to perform for prolonged periods as the treatment modality would require. These results emphasise that holographic diffusers exhibit minimal spectral impact, and longevity on the scale of treatment regimes which are crucial considerations for their prospective use case as treatments for amblyopia and diplopia.

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