Digital Commons Network^™

Mathematical Models Of Multisensory Detection And Decision-Making, Rebecca M. Brady

Doctoral

The brain seamlessly integrates signals from multiple sensory modalities to interpret the world efficiently. By using information from various senses, the brain can enhance its ability to detect and respond to stimuli more quickly and accurately. However, combining sensory cues from multiple modalities is only sometimes beneficial as it may lead to illusions and reduced behavioural performance. Behavioural and electrophysiological experiments have revealed that detection and decision-making strategies for multisensory cues evolve throughout human development and ageing. Additionally, studies have demonstrated that maladaptive multisensory processing is a key indicator of a proclivity to falls in older adults and individuals with …

Scaling Up Multi-Agent Reinforcement Learning For Large Agent Teams And Long-Horizon Tasks: A Survey, Minghong Geng, Shubham Pateria, Budhitama Subagdja, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

Multi-agent reinforcement learning (MARL) empowers multiple autonomous agents to acquire effective policies for collaborative problem-solving. Over the last decade, MARL has seen significant advancements, with numerous algorithms achieving impressive performance across various benchmarks and real-world applications. Nevertheless, the scalability of multi-agent systems, in terms of the number of agents and the length of the task horizon, remains a critical consideration for applying MARL methods to complex problem-solving. Given that a dedicated review of the existing approaches and challenges in scaling up multi-agent systems remains largely absent, this survey aims to bridge this gap by delivering a comprehensive review of MARL …

Videocreator: An Agentic System For Multi-Turn Video Production, Zhengyang Liang, Yan Shu, Cathal Gurrin, Nicu Sebe, Lizi Liao

Research Collection School Of Computing and Information Systems

Recent advances in video generation models enable visually compelling single clips. However, real-world video creation is inherently continuous and iterative: creators refine content over multiple rounds while maintaining narrative, style, and entity consistency. Existing standalone generators are largely stateless and lack memory of previously generated segments, making it difficult to produce a coherent and consistent video project. To address this gap, we present VideoCreator, a unified video agent that integrates generation and understanding with a project-level memory system. VideoCreator leverages understanding capabilities to perform fine-grained analysis of newly produced content and uses persistent memory to retain and reuse prior context …

Co-Designing With Autistic Livestreamers: Care, Constraints, And Trade-Offs In Livestreaming, Terrance Mok, Anthony Tang, Lora Oehlberg

Research Collection School Of Computing and Information Systems

Autistic livestreamers use platforms like Twitch for social connection, self-expression, and community, but these spaces also impose ongoing social and emotional demands. Prior work has documented these experiences, but less is known about what autistic creators themselves envision for the tools and platforms they use. We address this gap through a Research through Design (RtD) co-design study with three autistic Twitch streamers, using speculative artefacts as discussion prompts to explore how participants reasoned about potential livestreaming technologies. Across three co-design activities, we identify three overarching tensions shaping autistic streaming practice: Expression versus Misinterpretation and Harm; Public Participation versus Control and …

Language Embeddings Meet Shallow Autoencoders, Rodrigo Alves, Vojtěch Vančura, Pavel Kordík, Antoine Ledent

Research Collection School Of Computing and Information Systems

Shallow autoencoders are appealing recommenders due to their simplicity, scalability, and competitive retrieval quality, but they struggle in strict cold-start settings where new items have no interactions. We propose an inductive shallow autoencoder that leverages item side information (language embeddings) by fixing the decoder to item features and learning only an encoder in the same semantic space. To prevent trivial self-reconstruction without enforcing a hard zero diagonal, we introduce diagonal gating: a leave-one-item-out objective that blocks the self-copy shortcut only for the item being updated while retaining context from the rest of the user history. An alternating-style optimization trains the …

On The Number Of Ways To Express A Set As A Union Of Individually Interesting Sets, Alison Watson

Master's Theses

In a dataset that contains what ought rightly to be several distinct datasets placed in juxtaposition with each other, grouping datapoints based on observed similarities can be done in many ways. Topological Data Analysis (TDA) is a field of math that seeks to impose geometric structure onto datasets, thereby translating problems in statistics to problems in geometry or topology. A common truism in this field is “Data has shape and shape has meaning.” In this thesis, we use combinatorial and categorical arguments to demonstrate some shortcomings of a TDA approach on a class of inverse problems inspired by marine wildlife …

Climate-Driven Stochastic Modelling Of Crimean-Congo Haemorrhagic Fever Transmission In Uganda, P. G. Kpatchana, J. Aduda, K. M. Agboka

All Peer-Reviewed Publications

Crimean-Congo haemorrhagic fever (CCHF) is a climate-sensitive tick-borne zoonosis that remains a significant public health concern in Uganda, where temperature and vapour pressure deficit influence tick ecology and consequently disease transmission. This study aimed to develop and analyse a climate-driven stochastic model for CCHF transmission among ticks, livestock, and humans under environmental variability in Uganda. A compartmental transmission model was formulated and extended into a stochastic differential equation framework by incorporating multiplicative environmental noise. Climate-dependent tick recruitment, development, and mortality were parameterized using district-level temperature and vapour pressure deficit data to capture spatial heterogeneity in transmission risk. Theoretical analyses based …

Applications Of Prior And Novel Computational Tools In Mental Health Treatment, And Their Potential To Uncover The Explanatory Gap, Ambika Vyas

University Honors Theses

The explanatory gap is a widely discussed concept in scientific and philosophical literature. In neuroscience, the solution to the explanatory gap is highly sought out, but the general consensus is that it is unsolvable. Numerous articles discuss the explanatory gap alongside computational tools and how these tools could aid neuroscientists in uncovering the mental health explanatory gap. However, significant developments in machine learning have been made since 2020, coinciding with the rise in Large Language Models (LLMs). This thesis is a literature review on computational methods, tools, and devices developed and utilized by researchers to improve how mental health disorders …

Shallow-Marine Crinoid Genera May Have Been More Resilient Across Permian Extinction Events In Terms Of Richness Than Deep-Marine Crinoid Genera, Amelia C. Kolstad

University Honors Theses

Throughout the Phanerozoic, one of the most successful phyla of marine invertebrates has been Echinodermata. Echinodermata was particularly successful throughout the Paleozoic, with class Crinoidea making up a majority of occurrences. The proportion of echinoderm occurrences that are crinoids declined massively at the end of the Permian and continued to decrease into modern day, never fully recovering. One of the factors thought to have been so important for crinoid success in the Paleozoic and their decreasing success throughout geologic time has been their propensity for success in shallow-marine environments, though crinoids also exist within deep-marine environments. This study seeks to …

Public Acceptance Of Meat-Reduction Policies Across Cultures: Comparing Singapore And Switzerland, Bianca Wassmann, Shu Tian Ng, Mark Chong, Angela K. Y. Leung, Michael Siegrist

Research Collection Lee Kong Chian School Of Business

Purpose – As meat-reduction policies are discussed across the globe, many are met with public resistance. Cultural values may help explain this pushback, yet their role in shaping support for food policy remains poorly understood. This study is the first to apply cultural cognition theory to food policy by examining how cultural worldviews shape the acceptance of meat-reduction interventions in Singapore and Switzerland—two economically developed countries with contrasting cultural profiles. Design/methodology/approach – In an online survey, participants (Singapore: n = 357; Switzerland: n = 495) rated their acceptance of 11 meat-reduction interventions (e.g. taxes, subsidies, labelling). We then analysed to …

Draft Final 2022 Unreclaimed Sites Sampling: Ur-07 Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Gc-Ms-Based Comparative Analysis Of Compounds In Host Plants And Insect Gut Extracts, Rita Dill, Kimberly Smith, Shelia Okoth, Xavier Cheseto, Anne Osano

All Peer-Reviewed Publications

Background/Objectives: Herbivorous insects feed on plant tissues to obtain nutrients necessary for growth and development while simultaneously ingesting diverse plant secondary metabolites. Understanding the fate of these compounds during digestion is important for advancing knowledge of insect nutritional physiology and diet-associated biochemical processes. This study aimed to comparatively profile metabolites in host plants and corresponding insect gut extracts to generate insights into compound transfer and compositional changes within these systems. Methods: Gas Chromatography-Mass Spectrometry (GC-MS) metabolomics was combined with Ultraviolet-Visible (UV–Vis) quantification of total phenols and flavonoids to compare host plant tissues and insect gut extracts in three systems: fall …

Interfold: Learning Interpretable Diffusion Manifolds Beyond Binary Samples, Alexander Vincent Lewi, Rainer Tan, Shengfeng He

Research Collection School Of Computing and Information Systems

We propose InterFold, a framework for learning and applying interpretable semantic manifolds in latent diffusion models, without requiring binary or paired supervision. Existing methods for semantic editing either rely on limited paired data or uncover only coarse, unsupervised directions that fail to capture user-specific, fine-grained attributes. InterFold addresses these limitations by learning a target attribute manifold in the H-space of diffusion models using only a set of positive, unlabeled examples. To edit a new image, InterFold projects its H-space representation toward this learned manifold through test-time optimization, enabling precise, identity-preserving modifications of complex, non-binary concepts. To make these edits effective …

Perceptual And Geometric Advances In Crowd Simulation, Bilas Talukdar

Dissertations

Simulating realistic crowd motion remains a fundamental challenge in computer graphics and multi-agent systems, as it requires modeling both physically plausible interactions and perceptually natural behaviors. Existing crowd simulation methods typically employ simplified geometric abstractions, most commonly circular agent representations, and model navigation using either analytical interaction formulations (e.g., force, velocity, or constraint-based methods) or learned policies derived through reinforcement learning. Despite their effectiveness, these approaches often overlook detailed geometric structure and do not explicitly account for perceptual realism. This dissertation addresses these challenges by improving the realism of virtual crowd simulation through two key advancements: perceptual preference learning and …

Role Of Technical Assistance In Pollution Prevention In Massachusetts Craft Breweries, Shubhechchhya Regmi

Graduate Masters Theses

This study aims to examine pollution from Massachusetts craft breweries, and if it can be lessened through a pollution prevention program. This study analyzed data from two assessments with the aim of analyzing the role of technical assistance in pollution prevention across eight impact categories. The first assessment was conducted on 29 MA breweries between 2022 and 2024, and 23 were assessed a second time (in summer 2024 and summer 2025). Craft breweries face several constraints in adopting pollution prevention practices the pollution prevention program known as BetterBev helps to bridge this gap by providing technical assistance, identifying inefficiency practices …

Small Molecule Antioxidants As Potential Therapeutics For Preeclampsia, Maxim Mastyugin

Graduate Doctoral Dissertations

The major goal of this work was to develop a therapeutic intervention against preeclampsia (PE). Preeclampsia affects up to 5-7% of all pregnancies and has no causative treatments. It is associated with oxidative stress caused by a prolonged ischemic state and increase in reactive oxygen species (ROS) in the placenta. The cardinal symptoms include high blood pressure, kidney dysfunction, and in severe cases, eclampsia. With no treatment for the underlying causes available, we offer small molecule antioxidants which may scavenge ROS in the placenta arising from the initiating event of PE, the oxidative stress. By reducing placental ROS, these antioxidants …

Electrospun Nanofiber Scaffolds For In Vitro 3d Tissue Engineering, Victoria E. Santillan, Samerender Nagam Hanumantharao, Stephanie Bule, Ronish M. Shrestha, Carter Rodzik, Alan Mendoza Estrada, Stephen L. Farias, Marina Tanasova, Smitha Rao

Michigan Tech Publications

Tissue engineering is widely used in research for investigating cellular proliferation, behavior, and responses to various stimuli. However, the predictive value of preclinical studies using cell culture plates is limited by the inability to recapitulate the complexity of the physiological microenvironment. Synthetic three-dimensional (3D) scaffolds can be engineered to mimic the complex morphology of the extracellular matrix of native tissues and can serve as physiologically relevant platforms for preclinical studies. In this study, 3D electrospun scaffolds were characterized to aid in breast cancer research. Unlike previous studies that focused primarily on scaffold fabrication or cell viability, this work systematically evaluates …

Fate Of Nitrogen Applied To Grassland In Animal Wastes, M Sherwood

IGC Proceedings (1977-2023)

The experiment was designed to determine the effects of land spreading of animal manures on the nutrient content of surface runoff water and infiltrating soil water. This report deals only with nitrogen (N) and attempts to quantify the losses through runoff, leaching, and volatilization of ammonia (NH3) as well as N uptake in the grass over a 3-year period. Experimental plots sited on grassland, on two soil types (a moderately drained loam and an impermeable gley), were equipped to collect surface runoff water. Ceramic probes were installed in each plot at 15-, 30-, 60-, and 100-cm depths to extract in­filtrating …

Nitrogen Losses From Urine-Affected Areas Of A New Zealand Pasture, Under Contrasting Seasonal Conditions, P R. Ball, D R. Keeney

IGC Proceedings (1977-2023)

Grazing ruminants aggregate large quantities of forage nitrogen (N) into urine patches. Pasture plots treated with urine N were studied to assess its fate under contrasting seasonal conditions: cool-moist (representing winter-spring); warm-moist (late spring-early summer), and warm-dry (late summer-autumn). A permanent ryegrass (Lolium perenne L.)-white clover (Trifolium repens L.) sward on free-draining alluvial soil was studied. 'freatments were replicated in randomized blocks. Urine N was applied at 30 or 60 g N/m2• Relevant measurements were then continued until treatment differences disappeared. Apparent N balances for urine treatments were compiled. Fixation by white clover was always greatly reduced in …

Effects Of Water Stress On Herbage Quality, J R. Wilson

IGC Proceedings (1977-2023)

Uncertainty exists about whether drought is detrimental to the nutritive quality of herbage. This paper tries to resolve this uncertainty by examining the influence of soil moisture on some herbage-quality characteristics. Unpublished data from my own work and review of published literature are presented. Field plots of three tropical grasses, green panic (Panicum maximum var. trichoglume), buffelgrass (Cenchrus ciliaris), and speargrass (Heteropogon contortus), were subjected to perioqs of controlled drought, and herbage from these plots was compared with that from well-watered plots. Leaf and stem dry-matter ?igestibility of water-stressed herbage was either similar to or higher than that of unstressed …

Consumption Rates And Desert Grassland Herbivores, R D. Pieper

IGC Proceedings (1977-2023)

Studies were conducted on a desert grassland range in southern New Mexico for 3 years to determine relative consumption rates of the main herbivores utilizing these range areas. Consumption of some groups (cattle, pronghorn antelope, and rabbits) was determined from direct estimates of intake/individual, and density was determined from censusing procedures or known stock rates. Consumption by other groups (birds, rodents, and invertebrates) was determined from census information relating to age structure of the population and metabolic rate. Consumption by all herbivores averaged less than 5 % of the above-ground net primary productivity for the 3 years of the study. …

Performance Of A Subtropical Legume-Grass Pasture Under Different Grazing Management Systems, G E. Maraschin, S C. Mella, G S. Irulegui, J Riboldi

IGC Proceedings (1977-2023)

Agronomic evaluation of the dynamics of tropical legume-based pastures is relevant in assessing the response of their com­ponents within systems of grazing management. The response of tropical legume-grass mixtures to periods of rest and grazing pressure and the combinations that result in meaningful legume content in the mixture need to be known. A central composite design was used to study the performance of a Desmodium intortum (Mill.) U rb. and Paspalum gttenoarum Arech. pasture mixture to 14, 28, 42, 56, and 70daysofrestcombinedwith 2.0%, 3.5%, 5.0%, 6.5%, and 8.0% BW(i.e., kg dry matter (DM) on offer/day/100 kg body weight) as grazing …

Legume Establishment In Grass-Dominant Swards: Concept And History In Kentucky, T H. Taylor, W C. Templeton Jr

IGC Proceedings (1977-2023)

Grassland farming has been practiced for 2 centuries in central Kentucky and for shorter periods in other parts of the state. Savannas and tallgrass prairies were severely grazed by domestic animals and row-cropped by early settlers, destroying most of the indigenous plant species. By the early part of the 19th century, beef cattle were being produced on bluegrass (Poa pratensis L.) pastures and driven on foot to east-coast markets. During the first century of settlement, farmers learned to top-seed legumes into grass sods, and in the course of the last hundred years development of grassland technology for establishing legumes …

Seed And Seedling Dynamics Of Annual Medic Pastures In South Australia, E D. Carter

IGC Proceedings (1977-2023)

Annual species of Medicago (i.e., medics) are the key to successful cereal-pasture rotations in the integrated crop-livestock farming systems on the neutral to alkaline soils of southern Australia. However, many medic stands have deteriorated in recent years. This deterioration has prompted research on the effects of grazing sheep on the seed-seedling dynamics of annual medic­based pastures in the Mediterranean environment of South Australia, aiming to quantify the impact of medic seed reserves in or on the soil upon pasture establishment and productivty.

Animal-house experiments involving the feeding of purepod and pod-chaff diets to sheep and a field experiment have been …

Physiology Of Growth Of A Grazed Sward, E L. Leafe, A J. Parsons

IGC Proceedings (1977-2023)

To improve our understanding of grassland utilization under grazing, the physiology of a grazed sward was investigated. An enclosure method, infrared gas analysis, and radiocarbon were used to measure sward and single-leaf photosynthesis and assimilate utilization. Intake by sheep was also measured. Expanding and recently expanded leaves had high rates of net photosynthesis but leaf sheaths, whose projected area in a "hard" grazed sward equaled that of the lamina, had low efficiency and contributed little to canopy photosynthesis. But because high leaf efficiency did not compensate for the small leaf area, canopy photosynthesis decreased markedly as grazing intensity increased. Twice …

Grassland Development In The Southern Highlands Of Peru, E J. Stevens, P Villalta

IGC Proceedings (1977-2023)

This paper describes grassland development in Peru. Vegetation of the high alpine region of Peru, which occupies some 4 million ha, is dominated by native grasses normally producing less than 2,000 kg/ha dry matter annually. On land with ade­quate soil moisture, pastures based on perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.) were established successfully, but on drier sites alfalfa proved superior, producing over 12,000 kg/ha/yr in some trials. Alfalfa and clovers were also successfully introduced into improved native pastures by mechanical direct seeding and by hand sowing. With direct seeding, dry-matter production increased from about …

Pasture Evaluation In The Desertic Zone Of Venezuela For The Development Of Goat Production, A Gallardo, A Leone

IGC Proceedings (1977-2023)

The desertic zone of Venezuela is an area of approximately 4.1 million ha that represents 4.8 % of the total national territory, on which there are two million goats. Goats represent the main, if not the only, income source for 60,000 rural families. According to UNESCO (1973), the desertic zone of the country comprises two vegetation types, evergreen scrub and deciduous scrub. In each of these zones the plant species consumed by goats were collected and, for those plant parts consumed by the animals, chemically analyzed to determine nutritive value. Forage plants from other tropical countries were also in­troduced and …

Evaluation Of Biological Components In Decision-Making In Forage Allocation, J E. Skiles, G M. Van Dyne

IGC Proceedings (1977-2023)

Forage allocation to mixtures of large herbivores is accomplished by minimizing the difference between the available herbage and the required forage for animals on rangeland. Availability is determined in part by the plant's physiological tolerance to grazing or its allowable-use factor and the animal preference for that plant, measured in part by the proper-use factor. The mix of large herbivores on the rangeland must also be considered. The grazing requirements for animals are dependent on animal preference for plant species and on the total forage intake rates. This paper presents an analysis of these concepts and published information. The concept …

Effect Of Converting Chaparral To Grassland On Soil Fertility In A Mediterranean-Type Climate, M B. Jones, R L. Koenigs, C E. Vaughn, A H. Murphy

IGC Proceedings (1977-2023)

In the region of Mediterranean-type climate in California, brush is converted to grassland to reduce fire hazards, increase feed for herbivores, and increase water yields. There is little information on how this change of cover type affects soil fertility over a long period. Research was initiated to measure the long-term effect of converting brush to grass on the availability of nutrients in the soil. In 1956 chaparral growing on Los Gatos soil (fine-loamy, mixed mesic family of typic argixerolls) was crushed, burned, and seeded to grasses and clovers, and half the area was fenced to exclude herbivores. Sprouting brush either …

Resource Allocation For Animal-Grassland Systems, G W. Thomas

IGC Proceedings (1977-2023)

The production of animal products from grasslands is dependent upon an adequate resource base-particularly the availabil­ity ofland, water, and energy. In addition, range and pasture production systems must be designed to adjust to climatic varia­tions and to minimize adverse environmental impacts. Several new developments will have a significant impact on the future allocation of resources for animal agriculture: (1) in­creased competition for land and water, which is leading to transfers from agricultural to nonagricultural uses; (2) increasing costs and decreasing availability of "cultural energy" (particularly fossil fuels); (3) more pressure to divert grains and feed con­centrates from animals to direct …