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Anomaly Detection in Smart Grids Using Blockchain-Integrated Collaborative Decision-Making Systems
No full textThe growing reliance on smart grids introduces significant challenges in detecting and mitigating anomalies, disrupting critical operations, and leading to system-wide failures. This thesis presents a novel framework for anomaly detection in smart grids by utilizing 10 distinct machine learning models—Autoencoder, LSTM, RNN, CNN, TCN, MLP, Random Forest, SVM, KNN, and Logistic Regression—trained locally on client-specific data. When making a real-time decision about anomalies, the clients share their own decisions as experts, and the system securely and collaboratively makes final expert-based global decisions.
A key innovation of this framework is integrating blockchain technology for secure, collaborative, and decentralized anomaly validation. When a client detects an anomaly, it triggers a blockchain smart contract, initiating a voting process among the locally trained models. Each model will make its prediction and share it with the blockchain system via a smart function trigger. Following that, an average of these local decisions is taken, which results in a global decision ( majority voting) on the triggered anomaly. That global decision is tamper-resistant, transparent, and secure. The immutable nature of blockchain guarantees that all anomaly decisions are recorded and auditable, fostering trust among grid components.
This hybrid approach improves anomaly detection accuracy without compromising data security. Performance evaluations using metrics such as accuracy, precision, recall, and F1-score demonstrate the effectiveness of the collaborative decision-making system and the enhanced reliability introduced by blockchain validation. By combining these technologies, the proposed system addresses key challenges in modern smart grids, paving the way for scalable, secure, and self-adaptive anomaly detection mechanisms capable of mitigating evolving cyber-physical threats. Index Terms – Smart Grids, Anomaly Detection, Machine Learning Models, Blockchain, Smart Contracts, Majority Voting, Secure Decision-Making
Fast Pulse Response of Nanocrystalline Materials and Pulsed Applications
No full textThis work presents a comprehensive study of the characterization, simulation, and experimental validation of a Linear Transformer Driver (LTD). The research explores integrating nanocrystalline magnetic materials and SiC MOSFET switching technology to optimize LTD performance for high-voltage, fast-rise-time applications. Modeling magnetic materials in fast pulse situations is a complex but vital task in adequately designing and predicting pulsed power systems. ANSYS Maxwell transient magnetic simulations were used to model core magnetization dynamics, eddy current effects, and saturation behavior accurately. Solid and laminated modeling compositions were evaluated, with an effective conductivity sweep identifying 5 as optimal. A solid composition homogeneous core model proved most accurate in predicting B-H response and flux behavior using an effective conductivity, aligning closely with transformer and LTD experiments. A 10-stage LTD was designed and constructed, with detailed analyses of magnetic core properties, switching behavior, and output characteristics. Experimental tests assessed core performance under different operating conditions. Experimental LTD results demonstrated that reducing the center stock impedance and increasing gate voltage improved rise times without compromising MOSFET reliability. These findings provide key insights into optimizing next-generation solid-state LTDs, enhancing their efficiency, scalability, and applicability in high-power pulsed systems
Ultrasonic Desorption from an Ionic Liquid Loop for Continuously Regenerable CO2 Removal from Spacecraft Cabin Atmospheres
No full textBryce Loging, University of Colorado - Boulder, United StatesJesús Meléndez Gil, University of Colorado - Boulder, United StatesAshwin Balaji, University of Colorado - Boulder, United StatesJackson Castle, University of Colorado - Boulder, United StatesSteven Liu, University of Colorado - Boulder, United StatesZoë Major, University of Colorado - Boulder, United StatesMarius Li Jiang Merten, University of Colorado - Boulder, United StatesSenaa Mirza, University of Colorado - Boulder, United StatesJack Priske, University of Colorado - Boulder, United StatesAnthony Rifaat, University of Colorado - Boulder, United StatesTyndall Rounsefell, University of Colorado - Boulder, United StatesBrian Terasaki, University of Colorado - Boulder, United StatesMarjorie Trahan, University of Colorado - Boulder, United StatesBrice Anderson, University of Colorado - Boulder, United StatesDakota Kelly, University of Colorado - Boulder, United StatesJames Nabity, University of Colorado - Boulder, United StatesICES302: Physico-Chemical Life Support- Air Revitalization
Systems -Technology and Process DevelopmentThe 54th International Conference on Environmental Systems was held in Prague, Czechia, on 13 July 2025 through 17 July 2025.The CO2 Environmental Removal for Extended-duration
Spaceflight (CERES) student team at the University of
Colorado Boulder uses ionic liquid (IL)-based concepts for
regenerable CO2 removal from simulated cabin atmospheres.
The process described here utilizes an ionic liquid loop to
connect the absorption and desorption modules that together
form a closed loop continuously regenerative system. The
first module, the “absorber”, is a hollow-fiber membrane
contactor used to provide a contacting surface between a
CO2-laden atmosphere stream and the flowing IL. The IL
absorbs CO2 from the cabin atmosphere stream. The CO2-rich
IL flows into a custom flat-plate “desorber” module to
extract CO2. A vacuum pump creates a negative pressure
differential in the headspace of the desorber with respect
to the partial pressure of absorbed CO2 (ppCO2). In
combination with negative pressure, an ultrasonic
transducer attached to the desorber module is used to
enhance the desorption of weakly bonded CO2 from the ionic
liquid. Once the CO2 is expelled from the system, the
regenerated IL loops back to the absorber module for
continuous CO2 removal. Through testing, data showed that
the system was effectively absorbing and desorbing CO2,
demonstrating the function of the system. However, a
software failure of the ultrasonic system prevented the
investigation of ultrasonic desorption, which will remain
the focus of future work. Here, we present our system
design and report the results from experiments to
characterize the CO2 transport rate under varying
conditions of cabin atmosphere CO2 concentration,
atmosphere, and ionic liquid flow rates
Dragonfly: Detailed Thermal Control System Design
No full textKurt Gonter, Johns Hopkins University Applied Physics Laboratory, United StatesZhaojuan (Jane) He, Johns Hopkins University Applied Physics Laboratory, United StatesBruce Williams, Johns Hopkins University Applied Physics Laboratory, United StatesHui Liu, Johns Hopkins University Applied Physics Laboratory, United StatesAhmed Abir, Johns Hopkins University Applied Physics Laboratory, United StatesDahway Lin, Johns Hopkins University Applied Physics Laboratory, United StatesCollette Gillaspie, Johns Hopkins University Applied Physics Laboratory, United StatesMarisa Teti, Johns Hopkins University Applied Physics Laboratory, United StatesEvan Cosentino, Johns Hopkins University Applied Physics Laboratory, United StatesElisabeth Abel, Johns Hopkins University Applied Physics Laboratory, United StatesICES102: Thermal Control for Planetary and Small Body
Surface MissionsThe 54th International Conference on Environmental Systems was held in Prague, Czechia, on 13 July 2025 through 17 July 2025.Dragonfly is a NASA New Frontiers mission that will send a
rotorcraft lander to Titan, which has low gravity and a
dense 94K cryogenic nitrogen atmosphere. The lander Thermal
Control System (TCS) uses fans to circulate Titan
atmosphere internally, distributing heat from its MMRTG
power source to all internal components. In the last two
years, the system design has evolved significantly, with
special attention paid to improving the thermal control
system design in multiple areas to reach a CDR level of
maturity. Lander air inlet temperatures, previously
controlled via wall-mounted heat exchangers, are now
controlled using a composite external ducting system and
airflow diverter mechanism mounted to the lander belly. The
primary lander insulation material was updated to Solimide
16 after extensive testing, as Rohacell foam was found to
be prone to cracking and deformation. Additionally, to
increase system robustness on the launch pad after MMRTG
integration, a venting system was added to create a
flowpath between the lander and its external environment to
prevent battery overheating. This paper will provide an
overview of the matured thermal control system design and
will document key changes implemented since Mission PDR to
close the design with sufficient temperature margin, heat
leak margin, and control authority
Testing and Characterization of a Catalytic Oxidizer for Trace Contaminant Control
No full textJoe Klopotic, Sierra Space Corporation, United StatesNate Shakouri, Sierra Space Corporation, United StatesZachary Petrie, Sierra Space Corporation, United StatesJohn Wetzel, Sierra Space Corporation, United StatesICES302: Physico-Chemical Life Support- Air Revitalization
Systems -Technology and Process DevelopmentThe 54th International Conference on Environmental Systems was held in Prague, Czechia, on 13 July 2025 through 17 July 2025.In this paper, we present the latest advancements in the
development of the Catalytic Oxidizer (CatOx) for the Trash
Compaction & Processing System (TCPS) designed for
long-duration space missions. The TCPS is engineered to
compress, safen, and dry crew-generated standard trash,
recover and recycle water, and manage gaseous effluent
produced during trash processing. During the
high-temperature processing of trash, gaseous effluent
containing Volatile Organic Compounds (VOCs) and other
complex contaminants is emitted. To conserve valuable
resources during flight, these gases are managed and
recycled to minimize consumable losses. The CatOx,
developed by Sierra Space, treats this contaminated gas,
rendering it safe for reintroduction into the cabin
environment by catalytically decomposing VOCs at high
temperatures using a specially synthesized catalyst. The
resulting gas outflows can be safely released into the
cabin atmosphere or through other downstream systems. The
TCPS CatOx operates effectively across diverse pressure
ranges and can be adapted for other trace contaminant
control applications in spaceflight. This paper details the
testing of the CatOx using realistic trace contaminants,
presenting data on its performance across a broad spectrum
of operating conditions. Additionally, the characterization
of the catalyst is discussed, including X-ray Diffraction
(XRD), chemisorption, and Brunauer-Emmett-Teller (BET)
surface area analysis. Performance measures such as
destruction efficiency, thermal performance, and
suitability for integration with other life-support systems
are also evaluated to support the development of TCPS
flight hardware
West African Immigrant Communication Experiences in US Healthcare Settings
No full textGood communication between patients and healthcare providers is vital to ensure quality of care. This study discusses communication barriers faced by West African immigrant patients within the U.S. healthcare system, including language and accent difficulties, cultural competence, ethnic beliefs, and accessibility to healthcare. This research uses qualitative interviews to understand further how barriers affect patient outcomes and satisfaction. Findings show that language and cultural misinterpretations are familiar with treatment delays, inappropriate care, distrust of healthcare providers, and low healthcare utilization rates. Moreover, patients are discouraged from seeking timely care due to perceived rudeness and exclusionary attitudes of medical professionals. All of this notwithstanding, the study suggests ways to tackle these problems, such as providing cultural sensitivity training to healthcare providers, increasing the number of African healthcare professionals, and improving patient education initiatives. Systemic improvements to bridge communication gaps and improve healthcare access for West African immigrant patients can be promoted by developing and implementing culturally competent care healthcare policies, which in turn encourage more active patient involvement. These findings highlight the need for additional research and targeted interventions to achieve high-quality, inclusive care for this population
Emergent Literacy Development in the Absence of Parent Involvement: How Teachers Recognize the Literacies of Socioeconomically Disadvantaged Students
No full textThe preschool years lay a crucial foundation for children's future academic success. However, significant disparities exist in early literacy experiences, with children from low-socioeconomic backgrounds often entering school with varying levels of preparedness. This disparity stems from diverse home literacy environments, where children acquire foundational literacy skills through family interactions, and cultural experiences. Teachers in primary grades often face the challenge of understanding and leveraging the unique cultural and linguistic backgrounds of their diverse student population. Traditional approaches may inadvertently perpetuate deficit-based views of families from low-income backgrounds, perceiving them as lacking the resources and support necessary for their children's academic success. The Funds of Knowledge (FoK) framework challenges this deficit model by recognizing that all families possess valuable knowledge and skills acquired through their lived experiences. This research aims to investigate the specific Funds of Knowledge that primary students from low-socioeconomic backgrounds bring to the classroom. Furthermore, the study will explore how teachers can effectively recognize and incorporate these valuable resources into their instructional practices, thereby creating more equitable and inclusive learning environment for all students
NLP Analysis in the Intersection of RLHF and NER
No full textNamed Entity Recognition (NER) plays a crucial role in Natural Language
Processing(NLP) by identifying and classifying named entities such as persons,
organizations, and locations within the textual data. Traditional NER mod-
els firstly depend on supervised learning techniques and manually annotated
datasets. However, such a method for some times struggles with generalization,
domain adaptation, and handling noisy data. To address these challenges, this
research explores a novel approach by integrating reinforcement learning with
human feedback(RLHF) into the NER framework. By using an actor-critic Re-
inforcement Learning paradigm, the model continuously improves recognition
through iterative feedback and reward-based mechanisms.
The proposed system employs GloVe embeddings to capture contextual
word representations, look after a semantic understanding of textual data. A
bidirectional long-shot-term memory network (BiLSTM) is used as
a feature extractor to encode sequential dependencies, followed by an actor
network responsible for predicting labels and a critic network evaluating the
predicted results. The model interacts with an environment where tokenized
words are processed sequentially and rewards are assigned based on correct
classifications. A reinforcement learning policy updates the model parameters
based on observed rewards, allowed dynamic adaptation, and improved perfor-
mance over multiple episodes.
To evaluate the effectiveness of our approach, we train and test the model on
a custom data set extracted from textual sources. Performance is assessed using
accuracy, precision, and the F-1 score to ensure a comprehensive evalu-
ation. Experimental results demonstrate that the RLHF- based NER system
outperforms conventional supervised learning methods by reducing overfitting,
adapting to unseen entities, and leveraging human-in-the-loop feedback to refine
predictions. The findings suggest that reinforcement learning can enhance the
robustness and adaptability of NEW models, making them more suitable for
real-world applications such as information extraction, knowledge graph con-
struction, and automated document processing.
Research contributes to the evolving landscapes pf interactive NLP sys-
tems by combining deep learning with reinforcement learning, paving the way
for more adaptive and human-aligned text processing solutions. Future work
aims to improve reward mechanisms, integrate external knowledge sources for
improved entity disambiguation, and explore the model’s applicability across
multiple languages and specialized domains
Assessment of the Current Life Support System and Well-being on the International Space Station for a Sustainable Space Exploration
No full textShuichi Ichimura, Kyoto University, JapanYosuke A. Yamashiki, Kyoto University, JapanICES501: Life Support Systems Engineering and AnalysisThe 54th International Conference on Environmental Systems was held in Prague, Czechia, on 13 July 2025 through 17 July 2025.Life support systems in space have progressed
significantly, enabling partial recovery of oxygen and
water. Despite these advancements, human space missions
remain heavily reliant on resupply missions to deliver
essential resources, such as gas tanks, water bags, and
food from Earth. Achieving sustainable human space
exploration necessitates addressing both technical
challenges and the well-being of astronauts. This research
examines the current state of critical life support
elements—air, water, and food—as well as well-being factors
such as clothing, hygiene, and healthcare by analyzing
actual resupply data for the International Space Station
(ISS). Key findings reveal that resupply missions not only
deliver consumables like gas tanks and water bags but also
a significant volume of spare parts for maintaining
recovery systems. Food supplies, in particular, remain
entirely dependent on resupply missions. For well-being
elements, while the quantity of delivered supplies meets
the standards set by space agencies, astronauts report
discomfort with prolonged use of items such as clothing and
towels, especially exercise apparel, which develops
persistent unpleasant odors over time. The analysis also
identifies inefficiencies in resupply operations. Delivered
consumables and equipment constitute only 0.21% of the
total launch mass, highlighting the logistical challenges
of these missions. Dependence on frequent resupply missions
introduces physical and psychological challenges, including
risks of resource shortages, limited storage space
exacerbated by accumulating waste, odor management issues,
and stress from the complex cargo unloading and reloading.
As humanity sets its sights on exploration to the Moon and
beyond, the feasibility of frequent resupply missions
diminishes due to increased costs and extended delivery
times. This research emphasizes the urgent need for
advanced technologies to support sustainable human presence
in space. Proposed solutions include closed-loop life
support systems, innovative waste management strategies,
and improved designs to enhance astronaut comfort and
well-being during long-duration missions
Investigating Sexual Dimorphisms in Amaranthus palmeri
No full textSexual dimorphisms are a unique observation between male and female organisms of the same species that can provide insight into their evolutionary life history strategies. Within angiosperms, this can be applied to trait selection for each sex that maximizes their respective fitness. The following study explores a variety of morphological and phenological traits between male and female individuals of Amaranthus palmeri. I subjected individuals to a fertilizer treatment gradient of varying concentrations to compare to an optimal nutrient environment to observe how each sex responded to nutrient limitations. I then performed an ANOVA for differences in the measured traits between males and females and used these observations to construct life history strategies that appeared to maximize fitness for both sexes. Our results showed that male individuals of Amaranthus palmeri appeared to follow a life history strategy that maximizes pollen dispersal through early investment in height growth. In contrast, females of Amaranthus palmeri appear to follow the life history strategy of gradual resource accumulation to maximize photosynthesis at the time of seed production through greater leaf and above-ground vegetative biomass resource allocation