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Articles 1981 - 2010 of 302419

Full-Text Articles in Physical Sciences and Mathematics

Containerization On A Self-Supervised Active Foveated Approach To Computer Vision, Dario Dematties, Silvio Rizzi, George K. Thiruvathukal Jun 2024

Containerization On A Self-Supervised Active Foveated Approach To Computer Vision, Dario Dematties, Silvio Rizzi, George K. Thiruvathukal

Computer Science: Faculty Publications and Other Works

Scaling complexity and appropriate data sets availability for training current Computer Vision (CV) applications poses major challenges. We tackle these challenges finding inspiration in biology and introducing a Self-supervised (SS) active foveated approach for CV. In this paper we present our solution to achieve portability and reproducibility by means of containerization utilizing Singularity. We also show the parallelization scheme used to run our models on ThetaGPU–an Argonne Leadership Computing Facility (ALCF) machine of 24 NVIDIA DGX A100 nodes. We describe how to use mpi4py to provide DistributedDataParallel (DDP) with all the needed information about world size as well as global …


On The Size Of Maximal Binary Codes With 2, 3, And 4 Distances, Alexander Barg, Alexey Glazyrin, Wei-Jiun Kao, Ching-Yi Lai, Pin-Chieh Tseng, Wei-Hsuan Yu Jun 2024

On The Size Of Maximal Binary Codes With 2, 3, And 4 Distances, Alexander Barg, Alexey Glazyrin, Wei-Jiun Kao, Ching-Yi Lai, Pin-Chieh Tseng, Wei-Hsuan Yu

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

We address the maximum size of binary codes and binary constant weight codes with few distances. Previous works established a number of bounds for these quantities as well as the exact values for a range of small code lengths. As our main results, we determine the exact size of maximal binary codes with two distances for all lengths n≥6 as well as the exact size of maximal binary constant weight codes with 2, 3, and 4 distances for several values of the weight and for all but small lengths.


Enhancing Tumor Classification Through Machine Learning Algorithms For Breast Cancer Diagnosis, Lawrence Agbota, Edmund F. Agyemang, Priscilla Kissi-Appiah, Lateef Moshood, Akua Osei- Nkwantabisa, Vincent Agbenyeavu, Abraham Nsiah, Augustina Adjei Jun 2024

Enhancing Tumor Classification Through Machine Learning Algorithms For Breast Cancer Diagnosis, Lawrence Agbota, Edmund F. Agyemang, Priscilla Kissi-Appiah, Lateef Moshood, Akua Osei- Nkwantabisa, Vincent Agbenyeavu, Abraham Nsiah, Augustina Adjei

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

In cancer diagnosis, machine learning helps improve cancer detection by providing doctors with a second perspective and allowing for faster and more accurate determination and decisions. Numerous studies have used both classic machine learning approaches and deep learning to address cancer classification. In this study, we examine the efficacy of five commonly used machine learning algorithms; both traditional and deep learning models namely, Logistic Regression, Support Vector Machines (SVM), Random Forest (RF), Decision Tree and Deep Neural Networks (DNN). We analyze their ability to properly classify tumors as Benign or Malignant using the Wisconsin breast cancer dataset (WBCD). Random Forest …


Pseudo-Siamese Network Combined With Label-Free Raman Spectroscopy For The Quantification Of Mixed Trace Amounts Of Antibiotics In Human Milk: A Feasibility Study, Jing Yi Mou, Muhammad Usman, Jia Wei Tang, Quan Yuan, Zhang Wen Ma, Xin Ru Wen, Zhao Liu, Liang Wang Jun 2024

Pseudo-Siamese Network Combined With Label-Free Raman Spectroscopy For The Quantification Of Mixed Trace Amounts Of Antibiotics In Human Milk: A Feasibility Study, Jing Yi Mou, Muhammad Usman, Jia Wei Tang, Quan Yuan, Zhang Wen Ma, Xin Ru Wen, Zhao Liu, Liang Wang

Research outputs 2022 to 2026

The utilization of antibiotics is prevalent among lactating mothers. Hence, the rapid determination of trace amounts of antibiotics in human milk is crucial for ensuring the healthy development of infants. In this study, we constructed a human milk system containing residual doxycycline (DXC) and/or tetracycline (TC). Machine learning models and clustering algorithms were applied to classify and predict deficient concentrations of single and mixed antibiotics via label-free SERS spectra. The experimental results demonstrate that the CNN model has a recognition accuracy of 98.85% across optimal hyperparameter combinations. Furthermore, we employed Independent Component Analysis (ICA) and the pseudo-Siamese Convolutional Neural Network …


Ai Literacy Innovations: Chatgpt's Integration Into A First-Year Information Literacy Program, Taylor J. Greene, Douglas R. Dechow Jun 2024

Ai Literacy Innovations: Chatgpt's Integration Into A First-Year Information Literacy Program, Taylor J. Greene, Douglas R. Dechow

Library Presentations, Posters, and Audiovisual Materials

In the dynamic field of information technology, integration of Artificial Intelligence (AI) literacy into information literacy instruction is now essential to ensure the ethical and productive use of generative AI by our students. This poster demonstrates our innovative approach to embedding AI literacy within the first-year information literacy program at an R2 research university. We used a two-pronged strategy: an “AI Literacy” section in Canvas and practical demonstrations of applying ChatGPT in live library sessions. The Canvas module section equips students with foundational knowledge and critical thinking about using generative AI for research and learning activities. It covers AI fundamentals, …


Evaluating Past Progress And Assessing Prediction Breeding Strategies For Sustained Genetic Gains In The Louisiana Sugarcane Variety Development Program, Brayden A. Blanchard Jun 2024

Evaluating Past Progress And Assessing Prediction Breeding Strategies For Sustained Genetic Gains In The Louisiana Sugarcane Variety Development Program, Brayden A. Blanchard

LSU Doctoral Dissertations

The aim of this dissertation is to outline important considerations for the Louisiana Sugarcane Variety Development Program (LSVDP) as it pertains to historical progress, impact, goal setting, and new strategies for continued genetic gains. Industry progress was evaluated with robust regression models to quantify rates of productivity gains. Over the last 50 years, statistically significant productivity gains were identified in sucrose content (45%), cane yield (32.2%), and sugar yield (93%) while pairwise comparisons of decades showed that progress was incremental rather than rapid and sustained once achieved. The decade from 1990-1999 was identified as the only decade with a significant …


Comparison Of Value At Risk Using Historical And Monte Carlo Methods On Pt Xyz Stock Portofolio, Eka Fitriani, Yulial Hikmah, Ira Rosianal Hikmah Jun 2024

Comparison Of Value At Risk Using Historical And Monte Carlo Methods On Pt Xyz Stock Portofolio, Eka Fitriani, Yulial Hikmah, Ira Rosianal Hikmah

Jurnal Administrasi Bisnis Terapan

One way to achieve profits in a company is through investment activities. However, everything has risks. Investing can also be risky. Therefore, the relationship between risk and investment is important because it will influence the determination of investment selection. The problem faced by investors is choosing an efficient portfolio, or a portfolio that provides the smallest risk. This risk can be done by measuring risk, one of which is using the Value at Risk (VaR) measure. Measurement using Value at Risk has several methods that are quite popular, namely the Historical Method, Variance-Covariance, and Monte Carlo. In this research, the …


Hierarchical Quantized Autoencoders: Using Hierarchical Models For Data Compression Across Multiple Domains, Armani Lorenzo Rodriguez Jun 2024

Hierarchical Quantized Autoencoders: Using Hierarchical Models For Data Compression Across Multiple Domains, Armani Lorenzo Rodriguez

Theses and Dissertations

In the era of vast data processing and transmission, sending data over a channel for downstream operations is a very common occurrence. The bandwidth of this data channel acts as a limiting factor in this operation, capping the amount of data that can be sent over a time period. Therefore, in addition to pursuing advancements in networking technology, there exists a need for more efficient means of data compression. Learned compression is the application of machine learning models to the data compression problem, and in this study, we leverage the ability of neural networks to learn the underlying structure of …


Hyper-Dimensional Computing And Its Applications In Tinyml, Ellis A. Weglewski Jun 2024

Hyper-Dimensional Computing And Its Applications In Tinyml, Ellis A. Weglewski

Scholarly Horizons: University of Minnesota, Morris Undergraduate Journal

As computing systems enter the realm of nano form levels, new fields of computational development have spawned, each posing their own set of challenges. Amongst these fields is Tiny Machine Learning (tinyML), which aims to install machine learning on tiny embedded systems. The restrictions imposed upon algorithms by the limited hardware of nano-scale tiny systems make contemporary approaches to machine learning non-contenders. Hyperdimensional computing is an approach to representing data as high-dimensional vectors which allows for one-pass encoding and quick all-encompassing comparison operations via an associative memory. This approach is power-efficient, robust, and can be done in-memory, all of which …


Enhancing Evolutionary Computation Through Phylogenetic Analysis, Chenfei Peng Jun 2024

Enhancing Evolutionary Computation Through Phylogenetic Analysis, Chenfei Peng

Scholarly Horizons: University of Minnesota, Morris Undergraduate Journal

In this paper, we will provide an overview of the paper “Phylogeny-informed fitness estimation for test-based parent selection” by Lalejini, et al. [7] Phylogenies, or ancestry trees, provide a detailed look into the evolutionary journey of a population. In evolutionary computation, a phylogeny can represent the progress of an evolutionary algorithm through a search space. Although phylogenetic analysis is mainly used to deepen the understanding of evolutionary algorithms after they have been run, this study explores its potential use in real-time to enhance parent selection during evolutionary searches. The research by Lalejini, et al. introduces the concept of phylogeny-informed fitness …


The Potential Impact Of Endangered Species Legislation On Federal Grazing Lands And The Livestock Industry, G M. Luciuk, B Bristol, T W. Weins, D M. Boyle Jun 2024

The Potential Impact Of Endangered Species Legislation On Federal Grazing Lands And The Livestock Industry, G M. Luciuk, B Bristol, T W. Weins, D M. Boyle

IGC Proceedings (1993-2023)

Crown based grazing is an integral part of the management structure of cattle operations, and is very important to the economic fabric of rural communities. Federal crown lands, such as the PFRA operated community pastures are an integral part of the resource conservation efforts in western Canada. These lands represent a significant reservoir of the remaining natural lands which are important for wildlife habitat. Sustainable management of such contiguous blocks of land is essential for the maintenance of biodiversity. Proposed endangered species legislation would require the development of recovery plans on federal lands for endangered, threatened and extirpated species. Rural …


Concepts For Mining Landscape Development In Eastern Germany With Grazing Animals And Agroforestry, S Eichler, F Herzog Jun 2024

Concepts For Mining Landscape Development In Eastern Germany With Grazing Animals And Agroforestry, S Eichler, F Herzog

IGC Proceedings (1993-2023)

Leipzig South (Saxony) has been heavily transformed by open cast lignite mining. Alternative forms of land use are sought which contribute to an increase of biodiversity and an improvement of soil quality. This could be achieved by the selective introduction of grazing animals and perennials. Specific scenarios for open pits, dumping areas, open pits’ slopes and land reclaimed for agriculture are proposed. Socio-economic drawbacks are outlined.


The Use Of Grasslands To Improve Water Quality In The New York City Watershed, D J. Flaherty, J Drelich Jr Jun 2024

The Use Of Grasslands To Improve Water Quality In The New York City Watershed, D J. Flaherty, J Drelich Jr

IGC Proceedings (1993-2023)

The purpose of this paper is to demonstrate how grasslands are used in the New York City (NYC) Watershed to improve water quality. A Watershed Agricultural Program was established to voluntarily implement Pollution Prevention Best Management Practices on watershed farms. Grasslands have been used in Whole Farm Plans to reduce nutrients, sediments and other toxic materials reaching New York City’s water supply. Rotational grazing has been used to limit access to streams and stream banks and improve nutrient distribution on pastures. Improved grassland management also helps correct the nutrient balance on the farm and facilitates better nutrient management. Brush removal …


Objective Indicators For Monitoring Drought In Grasslands, D H. White, S M. Howden Jun 2024

Objective Indicators For Monitoring Drought In Grasslands, D H. White, S M. Howden

IGC Proceedings (1993-2023)

Australia’s National Drought Policy was ratified by the Commonwealth (Federal), State and Territory governments in 1992. However, a sequence of El Niño-based events that started in Queensland in 1991 culminated in much of Australia experiencing abnormally low rainfall throughout 1994 and into 1995. Many farmers experienced substantial loss of income. The Commonwealth government therefore devised measures to determine which areas had been exposed to exceptional drought so that financial assistance could be directed as effectively as possible. In this paper we discuss progress in developing regionally-sensitive indicators and methodologies to aid in future assessments of drought exceptional circumstances.


Are We Ignoring Science In Our Quest For Simplicity In Range Management?, W A. Laycock Jun 2024

Are We Ignoring Science In Our Quest For Simplicity In Range Management?, W A. Laycock

IGC Proceedings (1993-2023)

Accurate determination of range condition and trend is essential for proper range management. In the United States, the range condition model currently used is not based on up-to-date ecological knowledge. It assumes a single stable state (climax) and linear pathways. Multiple stable state models more accurately depict community dynamics but have not been widely accepted. U.S. Federal land management agencies are using surrogates, such as qualitative “instant trend” measures and substitution of utilization for measured condition and trend to guide management. Most of these short cuts are not based on science. Attacks on livestock grazing by environmentalists are based on …


Socio-Economic And Climate Change In Mongolia - Effects On Grassland Ecosystems, C Opp Jun 2024

Socio-Economic And Climate Change In Mongolia - Effects On Grassland Ecosystems, C Opp

IGC Proceedings (1993-2023)

In Mongolia, in combination with strong changes of the whole society during the past 76 years, from the feudal system to socialism and from the socialist system of planned development to the market economy, there are a lot of changes in the use of natural resources all over the country. In consequence of this a lot of effects on grassland ecosystems, caused by socio-economic and climate driving factors, were observed and studied in different scales: zonal, regional, local.


Integrating Biophysical And Economic Models For Assessing Impacts Of Change On Grazingland Ecosystems, J De Souza Neto, J R. Conner, J W. Stuth, W T. Hamilton, J W. Richardson Jun 2024

Integrating Biophysical And Economic Models For Assessing Impacts Of Change On Grazingland Ecosystems, J De Souza Neto, J R. Conner, J W. Stuth, W T. Hamilton, J W. Richardson

IGC Proceedings (1993-2023)

PHYGROW, a hydrologic-based forage simulation model, was parameterized to represent a typical South Texas ranch engaged in the production of cattle and meat goats with an indigenous population of white-tailed deer. Forage production and associated stocking rates for two cattle: goat ratios were simulated for 20 years. Two, ten-year weather scenarios, one representing normal conditions (30% drought years) and one representing dryer weather conditions (50% drought years) were analyzed. Management decision rules were developed for the region to produce estimates of annual animal production and operating cost for the enterprises in each of the four scenarios. These performance and cost …


Linear And Community-Based Processes Of Ethical Decision Making For Grassland Workers, Gary W. Fick Jun 2024

Linear And Community-Based Processes Of Ethical Decision Making For Grassland Workers, Gary W. Fick

IGC Proceedings (1993-2023)

Grasslands are basic elements in sustainable development, but few grassland workers are familiar with concepts of ethical decision making useful in integrating ecological, economic, and sociological components of sustainability. Most published procedures for ethical decision making are based on linear models for individualized social systems with modern technologies. In the context of sustainable agriculture, nonlinear community-based procedures may be more appropriate. In this paper, a nonlinear model from the Haudenosaunee (Iroquois) Indians is compared to more conventional linear procedures. After identification of a problem, linear models often leave the solution of the ethical dilemma (ranking ethical goals when they conflict) …


Policy Options For Decreasing N And P2o5 Losses From Grassland Based Dairy Farms, P.B M. Berentsen, G.W J. Giesen Jun 2024

Policy Options For Decreasing N And P2o5 Losses From Grassland Based Dairy Farms, P.B M. Berentsen, G.W J. Giesen

IGC Proceedings (1993-2023)

Policy instruments for reducing nutrient losses include extension and education, research, financial incentives such as subsidies and levies, and regulations. The potential of these instruments for reducing nitrogen (N), phosphate (P2O5), and ammonia (NH3) losses is examined for Dutch specialized dairy farms on sandy soils. A linear programming model is used to estimate policy impacts. Results indicate that efficiency improvements through extension, education, and research alone have the potential to decrease total N losses to government target levels in 2005 and to erase 92% of the gap between base and target P2O5 losses, but only 24% of the corresponding NH3 …


Production V Conservation: A Policy Dilemma In The Tree Clearing Debate In Queensland, Australia, J C. Scanlan, E J. Turner Jun 2024

Production V Conservation: A Policy Dilemma In The Tree Clearing Debate In Queensland, Australia, J C. Scanlan, E J. Turner

IGC Proceedings (1993-2023)

A process for developing policy for tree clearing that meets the competing goals of conservation and production has been followed. There were two levels at which policy was developed. An overall Statewide policy outlined general targets to meet commitments of the Queensland Government. Local guidelines were developed by a large number of groups containing representatives of government and interested conservation movement and industry representatives. The policy and the local guidelines are an important part of the process used to assess applications for permits to clear woody vegetation.


Forage Production And Performance Of Beef Yearlings Grazing Diploid And Tetraploid Crested Wheatgrass, J D. Bruynooghe, R.D H. Cohen, N W. Holt, P G. Jefferson Jun 2024

Forage Production And Performance Of Beef Yearlings Grazing Diploid And Tetraploid Crested Wheatgrass, J D. Bruynooghe, R.D H. Cohen, N W. Holt, P G. Jefferson

IGC Proceedings (1993-2023)

A series of experiments were conducted during 1994 and 1995 at Swift Current, Saskatchewan, Canada to evaluate forage production and animal performance on tetraploid Kirk (Agropyron cristatum (L.) Gaertn.) and diploid Fairway (Agropyron cristatum (L.) Gaertn.) crested wheatgrass pastures under grazing conditions imposed by beef (Bos taurus) yearling steers at four stock density levels (3, 4, 6 and 8 steers ha-1). Total ungrazed forage production for Kirk was greater (<0.05) than Fairway (6302 kg ha-1 vs. 5235 kg ha-1) in 1994 but less (P<0.05) than Fairway in 1995 (3709 kg ha-1 vs. 4633 kg ha-1). Animal performance (average daily gain, animal grazing days and total animal production) did not differ (P>0.05) for steers grazing either Kirk or Fairway pastures. Plant vigour and available energy reserves following one season of grazing were evaluated through etiolated growth with …


Vertical Distribution In Grass Swards: Interactions Between Dry Matter And Nutritional Quality, D R. Buckmaster, R H. Mohtar, S L. Fales Jun 2024

Vertical Distribution In Grass Swards: Interactions Between Dry Matter And Nutritional Quality, D R. Buckmaster, R H. Mohtar, S L. Fales

IGC Proceedings (1993-2023)

A field experiment was conducted to study the distribution of mass and quality over plant height throughout the growing season in a pure stand of orchardgrass (Dactylis glomerata L.). When plant density (expressed as kg DM/ha per cm height) is plotted against a height of strata, all treatments show a similar linear shape distribution. ADF and NDF concentrations declined with sward height. Fall treatments had lower ADF and NDF concentrations than summer treatments. Conversely, CP concentrations showed an increase with plant height. Fall treatments showed higher CP than spring and summer treatments. Defoliation management did not affect orchardgrass quality. …


Application Of The Phygrow Forage Production- Runoff Model For Regional Stocking Analysis, J W. Stuth, J R. Conner, W T. Hamilton, D M. Schmitt Jun 2024

Application Of The Phygrow Forage Production- Runoff Model For Regional Stocking Analysis, J W. Stuth, J R. Conner, W T. Hamilton, D M. Schmitt

IGC Proceedings (1993-2023)

A hydrologic-based forage production model, PHYGROW, was used to simulate forage production and carrying capacity of a subtropical shrubland complex of over 34 species grazed by various ratios of cattle and goats with a population of indigenous white-tailed deer over a 20-yr simulated weather profile. The diet selection algorithm allowed the three animal populations to selectively graze preferred foods based on preferences of plant species, plant parts, and live:dead status by phenological stage. A level of maximum utilization of key species was specified. An incremental analysis of cattle:goat demand ratio was analyzed to determine how different combinations of livestock were …


Using Nested Paddocks To Study Multiple-Paddock Grazing Systems, B E. Anderson, W W. Stroup, W H. Schacht Jun 2024

Using Nested Paddocks To Study Multiple-Paddock Grazing Systems, B E. Anderson, W W. Stroup, W H. Schacht

IGC Proceedings (1993-2023)

There is insufficient information to guide development of multiple paddock grazing systems. Measuring vegetation responses to grazing period/recovery period intervals is prohibitively expensive when using most grazing research designs. Nested paddock designs reduce land area, number of herds, and number of paddocks needed for comparisons. Nested paddocks permit comparisons of animal performance among whole pasture treatments but comparisons are limited for animal performance differences among grazing/recovery period lengths. Nonetheless, nested paddock designs efficiently document vegetation responses to grazing intervals, which may permit predictions of animal performance.


Relationship Between Broadleaf Dock (Rumex Obtusifolius L.) And Seasonal Yield Of Orchardgrass Grazed Pasture, Y Iijima, Y Kurokawa, T Monya, Y Suzuki Jun 2024

Relationship Between Broadleaf Dock (Rumex Obtusifolius L.) And Seasonal Yield Of Orchardgrass Grazed Pasture, Y Iijima, Y Kurokawa, T Monya, Y Suzuki

IGC Proceedings (1993-2023)

In order to grasp the ecology of R. obtusifolius and the effects of it on seasonal yield of grass in grazing pasture, we investigated seasonal sward characteristics and dry matter yield in grazing pasture. Dry matter yield and coverage of R. obtusifolius predominated those of grass after mid-June and mid-August, respectively. Throughout the year the coverage of R. obtusifolius negatively correlated to the grass yield. After August, the grass yield was negatively related to the yield and the population density of R. obtusifolius. From the facts described above, R. obtusifolius seems to reduce grass yield throughout the year, especially …


The Influence Of Light On The Succession Of Calcareous Grassland Using A Gis As An Instrument For Analysis, G Spatz, Th Fricke Jun 2024

The Influence Of Light On The Succession Of Calcareous Grassland Using A Gis As An Instrument For Analysis, G Spatz, Th Fricke

IGC Proceedings (1993-2023)

The change of light transmission along a gradient from shrub center to open grassland and its correlation to vegetation composition has been studied in two shrub surroundings on abandoned calcareous grassland. Light measurements were made at soil surface locations in high density and later interpolated to area maps. Low-growing plants were mapped in plots within the shrub area and their shapes subsequently digitized. Using SPANS GIS an overlay of maps representing light transmission, distance to shrub center and apearance of low-growing plants was made by calculating averages in a specified grid to create data sets for a statistical evaluation. The …


The Grazing Manager: A New Application Of The Carrying Capacity Concept, M M. Kothmann, R T. Hinnant Jun 2024

The Grazing Manager: A New Application Of The Carrying Capacity Concept, M M. Kothmann, R T. Hinnant

IGC Proceedings (1993-2023)

Common approaches to evaluating carrying capacity are stocking rate trials for research and trial and error adjustments for ranchers. These approaches are inadequate as operational decision guides for grazing management. The Grazing Manager (TGM) is a generalized management level dynamic model that provides a new approach to stocking rate analysis. Grazing pressure is integrated over time with a function called pasture demand ratio (PDR) which is based on cumulative forage demand relative to cumulative forage production within a forage year. PDR is a dynamic variable that standardizes the forage balance relationship and makes the analysis of stocking rate data more …


Accounting For Selective Grazing In The Stocking Rate Decision, M F. Quirk, J W. Stuth Jun 2024

Accounting For Selective Grazing In The Stocking Rate Decision, M F. Quirk, J W. Stuth

IGC Proceedings (1993-2023)

We describe the development and use of a simple, generic method for predicting botanical composition of herbivore diets, thereby allowing resource managers to consider selective foraging when setting stocking rates. For a particular season and herbivore, we found that forage species fall into one of 3 selection categories: preferred (consistently selected for), undesirable (consistently selected against), and variable (inconsistent selection pattern). Our studies showed that, for most situations, dietary composition is adequately predicted from regression relationships with the field proportions of preferred and undesirable species. We demonstrate how this method can help address issues such as the conservation of preferred …


Monitoring Water Meniscus Formation At Nanocontacts With Shear-Force Acousto Near-Field Microscopy, Xiaohua Wang, Rodolfo Fernandez, Theodore Brockman, Kacharat Supichayanggoon, Andres H. La Rosa Jun 2024

Monitoring Water Meniscus Formation At Nanocontacts With Shear-Force Acousto Near-Field Microscopy, Xiaohua Wang, Rodolfo Fernandez, Theodore Brockman, Kacharat Supichayanggoon, Andres H. La Rosa

Physics Faculty Publications and Presentations

Shear-force acoustic near-field microscopy (SANM) is employed to monitor stochastic formation and post dynamic response of a water meniscus that bridges a tapered gold probe (undergoing lateral oscillations of a few nanometers amplitude at constant frequency) and a flat (gold or silicon oxide) substrate. As the probe further approaches the substrate, its amplitude decreases. Shear forces (of yet unknown precise origin) are typically invoked to explain the apparently pure damping effects affecting the probe's motion. Herein, SANM measurements underscore instead the role of near-field acoustic emission from the water meniscus as an elastic energy dissipation channel involved in shear interactions. …


Research On Operational Protection Area Of Ils Glide Slope, Qingdong Li, Jiaquan Ye, Jian Xu Jun 2024

Research On Operational Protection Area Of Ils Glide Slope, Qingdong Li, Jiaquan Ye, Jian Xu

Journal of System Simulation

Abstract: The scientific protection for the operational protection area of the instrument landing system glide slope is of great significance to ensure the quality of civil aviation navigation space signals, the safety of aircraft approach operations, and the efficiency of airport operations. Combined with the concept evolution of the glide slope operational protection area, a comparative analysis of the delineation of the glide slope operational protection area required by the national civil aviation standards, industry standards, and Annex 10 Volume I of the Convention on International Civil Aviation is carried out. Taking the extra-large aircraft (A380-800) as an example, the …