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The Evolving International Grassland Congress, L R. Humphreys Jun 2024

The Evolving International Grassland Congress, L R. Humphreys

IGC Proceedings (1997-2023)

The locations of the International Grassland Congresses are listed. Analysis of the disciplinary themes of papers presented at five Congresses from 1937 to 1993 indicated a considerable homeostasis of content. The plant genetic base for grassland improvement received most attention, and this, together with plant physiology, plant ecology and soil science contributed 52 to 57 per cent of the subject matter at all five Congresses. Emergent topics are mentioned.


“Making The Bed”: Challenging Ideologies Of Ownership, Nonlocality, And Romanticism In The Age Of The Anthropocene, Ainsley P. Foster Apr 2024

“Making The Bed”: Challenging Ideologies Of Ownership, Nonlocality, And Romanticism In The Age Of The Anthropocene, Ainsley P. Foster

Belmont University Research Symposium (BURS)

The current Age of the Anthropocene marks a recent and rapid transition into a period in climate history that is notably defined by human impact. Modern Western sentiments of grief, frustration, and romanticism as a result of the interplay between domestic and corporate spaces seem to culminate in an overall attitude of apathy and acceptance of the Age of the Anthropocene. Various art forms collaborate to create the current conversation of the causatory and reactionary relationship that humans have with the Anthropocene, offering interpretations of how individuals and corporations view ownership of and responsibilities to the environment. There is a …


The Impact Of Concentrate Price On The Utilization Of Grazed And Conserved Grass, P. Crosson, P. O'Kiely, F. P. O'Mara, M. J. Drennan, M. Wallace Aug 2023

The Impact Of Concentrate Price On The Utilization Of Grazed And Conserved Grass, P. Crosson, P. O'Kiely, F. P. O'Mara, M. J. Drennan, M. Wallace

IGC Proceedings (1997-2023)

A linear programming model was designed and constructed to facilitate the identification of optimal beef production systems under varying technical and policy scenarios. The model operates at a systems level and most activities that could occur in Irish spring-calving, suckler beef production systems are included. In this paper, the components of the model are described together with a simple application of the model involving changing concentrate prices.


The Effect Of Dairy Cow Genotype On Modelled Greenhouse Gas Emissions Derived From Pasture Based Milk Production Systems, Dan K. Lovett, L. Shalloo, P. Dillon, Frank O'Mara Jun 2023

The Effect Of Dairy Cow Genotype On Modelled Greenhouse Gas Emissions Derived From Pasture Based Milk Production Systems, Dan K. Lovett, L. Shalloo, P. Dillon, Frank O'Mara

IGC Proceedings (1997-2023)

A three-year systems comparison study was undertaken to see if progressively increasing the genetic potential for milk production of the dairy cow is desirable within pastoral based systems of spring milk production (Kennedy et al., 2002). The production data was inputted into the Moorepark Dairy System Model (MDSM) (Shalloo et al., 2004) to describe the economic, biological and production efficiency of each system. Output was then used to model whole farm greenhouse gas (GHG) emissions (Lovett et al., in press) from the nine systems studied (three concentrate levels by three genotype levels). Only the genotype effects are …


A Systems Approach To Managing Greenhouse Gases On New Zealand Sheep And Beef Farms, M. G. Lambert, H. Clark Jun 2023

A Systems Approach To Managing Greenhouse Gases On New Zealand Sheep And Beef Farms, M. G. Lambert, H. Clark

IGC Proceedings (1997-2023)

Agriculture contributes more than 50% of New Zealand's greenhouse gas (GHG) emissions, mainly through release of methane (CH4) and nitrous oxide (N2O) from pastoral farms. Decisions on implementation of mitigation strategies will be made by individual farmers, who seek also to maintain financial performance in the face of declining terms of trade for commodities, hence leading to pressure to further intensify production. New Zealand (NZ) sheep & beef farms are typically hill country properties with a mixture of steep and easier topography, and year-round grazing of mainly permanent pastures. Specific GHG mitigation technologies will be difficult …


Year-Round Forage Systems For Beef Cows And Calves, J. P. Fontenot, W. M. Clapham, W. S. Swecker, Jr. D. Fiske, J. B. Hall, J. H. Fike, G. Scaglia Jun 2023

Year-Round Forage Systems For Beef Cows And Calves, J. P. Fontenot, W. M. Clapham, W. S. Swecker, Jr. D. Fiske, J. B. Hall, J. H. Fike, G. Scaglia

IGC Proceedings (1997-2023)

Beef cow systems in the USA are based on forages with little or no concentrates fed. Tall fescue (Festuca arundinacea Schreb. L.) is one of the important pasture forages in the lower Northeast and upper South (Allen et al., 2001). Limited research has been conducted on year-round all forage systems based on cool season forages. Stockpiling tall fescue in late summer-early fall provides good quality forage that is usually grazed rather than harvested. Forage systems including tall fescue and clover (Trifolium repens L.) produced excellent performance in beef cows and calves, with minimum inputs (Allen et al …


The Impact Of Concentrate Price On The Utilization Of Grazed And Conserved Grass, P. Crosson, P. O'Kiely, F. P. O'Mara, M. J. Drennan, M. Wallace Feb 2023

The Impact Of Concentrate Price On The Utilization Of Grazed And Conserved Grass, P. Crosson, P. O'Kiely, F. P. O'Mara, M. J. Drennan, M. Wallace

IGC Proceedings (1997-2023)

A linear programming model was designed and constructed to facilitate the identification of optimal beef production systems under varying technical and policy scenarios. The model operates at a systems level and most activities that could occur in Irish spring-calving, suckler beef production systems are included. In this paper, the components of the model are described together with a simple application of the model involving changing concentrate prices.


Overview Of Animal Production From Pastures In Ireland, M. J. Drennan, A. F. Carson, S. Crosse Feb 2023

Overview Of Animal Production From Pastures In Ireland, M. J. Drennan, A. F. Carson, S. Crosse

IGC Proceedings (1997-2023)

Key points

The importance of grassland to agriculture in Ireland is indicated by the fact that:

  1. Sixty percent of agricultural output is from grassland as cattle, milk and sheep products.
  2. Over 90% of the total farmed area is in grass.
  3. Livestock are almost entirely dependent on grazed grass for 200 to 235 days of the year.
  4. Grass conserved as silage is the main source of fodder in winter.
  5. To improve competitiveness changes are continuously taking place, which include:
  • increased suckler herd size and a movement to late maturing continental cattle breeds;
  • movement in the dairy herd towards Holstein with increased …


Introducing Systems Via Laplace Transforms, Ollie Nanyes Jan 2023

Introducing Systems Via Laplace Transforms, Ollie Nanyes

CODEE Journal

The purpose of this note is to show how to move from Laplace Transforms to a brief introduction to two dimensional systems of linear differential equations with only basic matrix algebra.


Are You Really Muted?: A Privacy Analysis Of Mute Buttons In Video Conferencing Apps, Yucheng Yang, Jack West, George K. Thiruvathukal, Neil Klingensmith, Kassem Fawaz Jul 2022

Are You Really Muted?: A Privacy Analysis Of Mute Buttons In Video Conferencing Apps, Yucheng Yang, Jack West, George K. Thiruvathukal, Neil Klingensmith, Kassem Fawaz

Computer Science: Faculty Publications and Other Works

In the post-pandemic era, video conferencing apps (VCAs) have converted previously private spaces — bedrooms, living rooms, and kitchens — into semi-public extensions of the office. And for the most part, users have accepted these apps in their personal space, without much thought about the permission models that govern the use of their personal data during meetings. While access to a device’s video camera is carefully controlled, little has been done to ensure the same level of privacy for accessing the microphone. In this work, we ask the question: what happens to the microphone data when a user clicks the …


New Forms Of Pastoral Mobility Among Sheep Herders In The Algerian Steppe; The Case Of Pastoralists Of Djelfa, Dihia Gaci, Jean-Pierre Boutonnet Jan 2022

New Forms Of Pastoral Mobility Among Sheep Herders In The Algerian Steppe; The Case Of Pastoralists Of Djelfa, Dihia Gaci, Jean-Pierre Boutonnet

IGC Proceedings (1997-2023)

The recent socio-economic, political and climatic changes experienced by the Algerian steppe for the last decades have led to profound changes in pastoral mobility practices. This study describes the new mobility practices as currently adopted by the breeders of the Djelfa region. The realization of 59 semi-directive surveys was conducted between 2014 and 2016 among breeders in different reception areas. Practices related to the distance travelled during an annual cycle, the transhumance calendar and itinerary and the passage or not in the homeland are diverse. These practices of mobility can vary from one year to another or during the life …


Iterative Scenarios For Social-Ecological Systems, D. Herrmann, K. Schwarz, C. Allen, D. Angeler, T. Eason, A. Garmestani Jan 2021

Iterative Scenarios For Social-Ecological Systems, D. Herrmann, K. Schwarz, C. Allen, D. Angeler, T. Eason, A. Garmestani

School of Natural Resources: Faculty Publications

No abstract provided.


Learning Across Disciplines In Socio-Environmental Problem Framing, D. Pennington, R. Bonnstetter, E. Gehrig, R. Stokes Jan 2021

Learning Across Disciplines In Socio-Environmental Problem Framing, D. Pennington, R. Bonnstetter, E. Gehrig, R. Stokes

School of Natural Resources: Faculty Publications

No abstract provided.


Law Library Blog (November 2020): Legal Beagle's Blog Archive, Roger Williams University School Of Law Nov 2020

Law Library Blog (November 2020): Legal Beagle's Blog Archive, Roger Williams University School Of Law

Law Library Newsletters/Blog

No abstract provided.


Technical Strategies Database Managers Use To Protect Systems From Security Breaches, Leonard Ogbonna Jan 2020

Technical Strategies Database Managers Use To Protect Systems From Security Breaches, Leonard Ogbonna

Walden Dissertations and Doctoral Studies

Healthcare organizations generate massive amounts of data through their databases that may be vulnerable to data breaches due to extensive user privileges, unpatched databases, standardized query language injections, weak passwords/usernames, and system weaknesses. The purpose of this qualitative multiple case study was to explore technical strategies database managers in Southeast/North Texas used to protect database systems from data breaches. The target population consisted of database managers from 2 healthcare organizations in this region. The integrated system theory of information security management was the conceptual framework. The data collection process included semistructured interviews with 9 database managers, including a review of …


Leveraging Variation Of Historical Number Systems To Build Understanding Of The Base-Ten Place-Value System, Eva Thanheiser, Kathleen Melhuish Apr 2019

Leveraging Variation Of Historical Number Systems To Build Understanding Of The Base-Ten Place-Value System, Eva Thanheiser, Kathleen Melhuish

Mathematics and Statistics Faculty Publications and Presentations

Prospective elementary school teachers (PTs) come to their mathematics courses fluent in using procedures for adding and subtracting multidigit whole numbers, but many are unaware of the essential features inherent in understanding the base-ten place-value system (i.e., grouping, place value, base). Understanding these features is crucial to understanding and teaching number and place value. The research aims of this paper are (1) to present a local instructional theory (LIT), designed to familiarize PTs with these features through comparison with historical number systems and (2) to present the effects of using the LIT in the PT classroom. A theory of learning …


Cybersecurity Strategies To Protect Information Systems In Small Financial Institutions, Johnny Fadel Rawass Jan 2019

Cybersecurity Strategies To Protect Information Systems In Small Financial Institutions, Johnny Fadel Rawass

Walden Dissertations and Doctoral Studies

Leaders of financial institutions face challenges in protecting data because of the increased use of computer networks in the commerce and governance aspects of their businesses. The purpose of this single case study was to explore the strategies that leaders of a small financial institution used to protect information systems from cyber threats. The actor-network theory was the conceptual framework for this study. Data were collected through face-to-face, semistructured interviews with 5 leaders of a small financial institution in Qatar and a review of company documents relevant to information security, cybersecurity, and risk management. Using thematic analysis and Yin'€™s 5-€step …


Rediscovering The Interpersonal: Models Of Networked Communication In New Media Performance, Alicia Champlin Aug 2018

Rediscovering The Interpersonal: Models Of Networked Communication In New Media Performance, Alicia Champlin

Electronic Theses and Dissertations

This paper examines the themes of human perception and participation within the contemporary paradigm and relates the hallmarks of the major paradigm shift which occurred in the mid-20th century from a structural view of the world to a systems view. In this context, the author’s creative practice is described, outlining a methodology for working with the communication networks and interpersonal feedback loops that help to define our relationships to each other and to media since that paradigm shift. This research is framed within a larger field of inquiry into the impact of contemporary New Media Art as we experience it. …


Application Memory Isolation On Ultra-Low-Power Mcus, Taylor Hardin, Ryan Scott, Patrick Proctor, Josiah Hester, Jacob Sorber, David Kotz Jul 2018

Application Memory Isolation On Ultra-Low-Power Mcus, Taylor Hardin, Ryan Scott, Patrick Proctor, Josiah Hester, Jacob Sorber, David Kotz

Dartmouth Scholarship

The proliferation of applications that handle sensitive user data on wearable platforms generates a critical need for embedded systems that offer strong security without sacrificing flexibility and long battery life. To secure sensitive information, such as health data, ultra-low-power wearables must isolate applications from each other and protect the underlying system from errant or malicious application code. These platforms typically use microcontrollers that lack sophisticated Memory Management Units (MMU). Some include a Memory Protection Unit (MPU), but current MPUs are inadequate to the task, leading platform developers to software-based memory-protection solutions. In this paper, we present our memory isolation technique, …


Design And Characterization Of An Affordable Laser Communication System, Andrea Tellez Jul 2018

Design And Characterization Of An Affordable Laser Communication System, Andrea Tellez

Theses and Dissertations

Over the last decades, an exponential growth in communication demand has been observed. Radio Frequency (RF) band has been one of the most used bandwidths for data transmission in the world. Given the influence and the continuous growth of communication technology, the RF spectrum is overpopulated. More efficient systems are necessary to meet the communication needs of this generation. A change to optical bandwidth is the most practical alternative to deal with the congestion of radio frequency.

The aim of this thesis is to present the features of Free Space Optical links with off-the-shelf components. A description of how these …


Theory, Computation, And Modeling Of Cancerous Systems, Sameed Ahmed Jan 2018

Theory, Computation, And Modeling Of Cancerous Systems, Sameed Ahmed

Theses and Dissertations

This dissertation focuses on three projects. In Chapter 1, we derive and implement the compact implicit integration factor method for numerically solving partial differential equations. In Chapters 2 and 3, we generalize and analyze a mathematical model for the nonlinear growth kinetics of breast cancer stem cells. And in Chapter 4, we develop a novel mathematical model for the HER2 signaling pathway to understand and predict breast cancer treatment. Due to the high order spatial derivatives and stiff reactions, severe temporal stability constraints on the time step are generally required when developing numerical methods for solving high order partial differential …


Colliding Wind Binaries With Orbital Motion: Line Wind Formulation, Brendan O'Connor Jun 2017

Colliding Wind Binaries With Orbital Motion: Line Wind Formulation, Brendan O'Connor

Honors Theses

Stars lose mass in the form of supersonic winds. In a binary star system, these winds collide to produce shockwaves. Such stellar wind collisions are observed in many binary star systems. Due to the orbital motion of the system, a trailing spiral structure is produced. We present a solution method in the co- rotating frame of the stars, which allow us to consider steady state solutions. This requires the inclusion of Coriolis and centrifugal forces, including their effects on the pre-shock winds, for which we were restricted to orbital speed slower than wind speeds. We assume efficient post-shock cooling, which …


Identifying Inexpensive Off-The-Shelf Laser Pointers For Multi-User Interaction On Large Scale Displays, Christopher S. Stuetzle, Barbara Cutler, Tyler Sammann Jan 2017

Identifying Inexpensive Off-The-Shelf Laser Pointers For Multi-User Interaction On Large Scale Displays, Christopher S. Stuetzle, Barbara Cutler, Tyler Sammann

Computer Science Faculty Publications

We present a method for identifying inexpensive, off-the-shelf laser pointers in a multiuser interaction environment on large-scale displays. We identify a laser pointer's personality, a measure of its output in a particular context. Our method requires a set of inexpensive and unmodified green lasers, a large screen, a projector, and a camera with an infrared (IR) filter. The camera detects the IR spillover from the green laser beam, while ignoring color information projected onto the screen. During a calibration phase, a radial histogram of each laser's IR spillover are used to represent the laser's personality. Our system is able to …


Strategies For U.S. City Government Enterprise Resource Planning System Implementation Success, Jennifer Miller Jan 2017

Strategies For U.S. City Government Enterprise Resource Planning System Implementation Success, Jennifer Miller

Walden Dissertations and Doctoral Studies

Strategies for enterprise resource planning (ERP) system implementation success have been a focus of scholars since the 1990s. Researchers have demonstrated that ERP system implementation could cause both system failures and organization failures, affecting both operations and stakeholders. The theory of constraints was the conceptual framework for this single qualitative case study that explored ERP system critical success factors (CSFs) and strategies U.S. city governments use to successfully implement ERP systems. One city government in New Mexico with a successful ERP system served as the case study's population. Data were collected from semistructured interviews and relevant documents and then open …


Assessing Infrastructure System Of Systems Integrity, Ricardo Peculis, Farid Shirvani, Pascal Perez Jan 2017

Assessing Infrastructure System Of Systems Integrity, Ricardo Peculis, Farid Shirvani, Pascal Perez

SMART Infrastructure Facility - Papers

Infrastructure refers to the fundamental facilities and systems serving a country, city, or area, including the services and facilities necessary for its economy to function. Infrastructure systems typically consist of interrelated constituent systems forming what is known as system of systems (SoS). Infrastructure systems present numerous challenges throughout their lifecycles. This paper addresses one of these challenges that is presented during operation, when managers need to report 'how well' the system is performing and finding ways to address the consequences of unexpected events that often degrade the intended performance. This state of system 'wellbeing' will be referred as system integrity …


Lifelong Machine Learning With Adaptive Multi-Agent Systems, Nicolas R. Verstaevel, Jeremy Boes, Julien Nigon, Dorian D'Amico, Marie-Pierre Gleizes Jan 2017

Lifelong Machine Learning With Adaptive Multi-Agent Systems, Nicolas R. Verstaevel, Jeremy Boes, Julien Nigon, Dorian D'Amico, Marie-Pierre Gleizes

SMART Infrastructure Facility - Papers

Sensors and actuators are progressively invading our everyday life as well as industrial processes. They form complex and pervasive systems usually called "ambient systems" or "cyber-physical systems". These systems are supposed to efficiently perform various and dynamic tasks in an ever-changing environment. They need to be able to learn and to self-adapt throughout their life, because designers cannot specify a priori all the interactions and situations they will face. These are strong requirements that push the need for lifelong machine learning, where devices can learn models and behaviours during their whole lifetime and are able to transfer them to perform …


Infrastructure System Of Systems Integrity, Ricardo Peculis, Farid Shirvani Jan 2017

Infrastructure System Of Systems Integrity, Ricardo Peculis, Farid Shirvani

SMART Infrastructure Facility - Papers

Infrastructure systems typically consist of technical structures comprising of physical and operational components of interrelated constituent systems forming what is now known as system of systems (SOS). The complexity and uncertainty of unforeseen events that are inherent characteristic of infrastructure systems makes it impossible to predict undesirable emergent behaviours that could push the operation of such systems away from their intended purposes. Infrastructure systems present numerous challenges throughout their lifecycles. This paper addresses one of these challenges that is presented during operation, when managers need to report 'how well' the system is performing and find ways to address the consequences …


Towards Computational Human Behavior Modeling For Just-In-Time Adaptive Interventions, Tylar Murray Nov 2016

Towards Computational Human Behavior Modeling For Just-In-Time Adaptive Interventions, Tylar Murray

USF Tampa Graduate Theses and Dissertations

The advent of powerful wearable devices and smartphones has enabled a new generation of “in-the-wild” user studies, adaptive behavioral intervention strategies, and context measurement. Though numerous proof-of-concept studies continue to push the limitations of what a behavioral scientist can do with these technologies, there remains a major methodological roadblock separating behavioral theory and application. Avatar-user interaction theory, for example, is not well defined in its formulation, and thus guidelines for intervention designers depend on heuristic methods and designer intuition. Computational modeling has been slow to move into behavioral science in general, but a growing population of behavioral scientists recognize this …


Systematic Elongation Of Thienyl Linkers And Their Effect On Optical And Electrochemical Properties In Carbazole-Bodipy Donor-Acceptor Systems, Alina Brzeczek, Katarzyna Piwowar, Wojciech Domagala, Mikotaj M. Mikotajczyk, Krzysztof Walczak, Pawel W. Wagner Jan 2016

Systematic Elongation Of Thienyl Linkers And Their Effect On Optical And Electrochemical Properties In Carbazole-Bodipy Donor-Acceptor Systems, Alina Brzeczek, Katarzyna Piwowar, Wojciech Domagala, Mikotaj M. Mikotajczyk, Krzysztof Walczak, Pawel W. Wagner

Australian Institute for Innovative Materials - Papers

Synthesis, spectral and electrochemical properties of a series of new panchromatic BODIPY donor-acceptor-donor derivatives, comprising carbazole conjugated with systematically elongated framework by thiophene-based linkers were investigated. It has been found that elongation of the π-system with one thiophene unit shifts the spectra toward near infrared, while incorporation of next thiophene derivatives has only limited influence on the lowest energy transition, causing no further shift of absorption maxima. Elongation of π-conjugation of the donor arm tunes the electron properties, influencing the ionization potential (IP) and electron affinity (EA) values of the molecules. The experimental results are supported by quantum chemical computations …


Case Study: A Model Based Systems Engineering (Mbse) Framework For Characterising Transportation Systems Over The Full Life Cycle, William R. Scott, Richard Fullalove, Gary Arabian, Allan P. Campbell Jan 2016

Case Study: A Model Based Systems Engineering (Mbse) Framework For Characterising Transportation Systems Over The Full Life Cycle, William R. Scott, Richard Fullalove, Gary Arabian, Allan P. Campbell

SMART Infrastructure Facility - Papers

Development of transport infrastructure has significant challenges including acquisition lag, phased evolution, multiple disparate stakeholders and environment-specific issues. The Asset Standards Authority (ASA) at TfNSW is introducing MBSE to address these challenges. Instrumental to the introduction is the development of a framework that structures the available data and provides guidance and traceability between the data sets. This framework combines the enterprise-level drivers with the lower level drivers such as standards to outline a generic conceptual design for a transport system. This conceptual design is then used to guide future system development. The outcome is future project information based on greater, …