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Title: Modeling and Control of Boundary Constrained Granular Swarm Robots
Creator: Mulroy, Declan Augustine
Date: 2023
Description: Soft robots offer many advantages that traditional robotic systems do not. Soft robotic systems are able to safely interact with their...
Show moreSoft robots offer many advantages that traditional robotic systems do not. Soft robotic systems are able to safely interact with their environment and tolerate large deformations. This is due to being composed of soft materials, which allows them to be subjected to and experience large deformations. However, they still have limitations in their maneuverability, locomotion, and force exertion. Moreover, they usually require external tethering or other specialized systems, such as pneumatic devices, to function. To address some of these limitations, a novel class of robotic systems has emerged called a boundary-constrained granular swarm robot.A boundary-constrained granular swarm robot is composed of a closed-loop series of active sub-robots, each with the ability to locomote. Each sub-robot is connected to its neighbors with an elastic membrane, which forms a single robot. The membrane encloses a passive granular interior, which provides structure and allows the robot to switch between rigid and soft states via granular jamming phase transitions. This allows for the robotic system to exploit the desirable characteristics of both soft and rigid robots. However, there is limited research with regards to modeling and controlling this system due to its novelty. This thesis addresses this gap by presenting several simulation frameworks, which incorporates multi-body dynamics and non-smooth contact dynamics to model the forward dynamics of the system. These models are able to account for the frictional effects, and the contact forces experienced by the system. The developed models are verified through experimental prototypes to ensure the models are able to capture the general behaviors of the system. Additionally, gradient-based control algorithms are presented and applied to simulated and experimental systems to have each of them form arbitrary shapes, morph between shapes, grasp arbitrarily shaped objects, and navigate narrow corridors. All of these objectives have been accomplished in previous systems, however, this thesis will demonstrate this system is one of the first to be able to accomplish all four. Moreover, it is able to by using a single control framework. In addition, this thesis will present the application distance functions, R-functions, and space-time transfinite interpolation for control purposes. These techniques are commonly utilized in graphics and animation theory, and will be applied to gradient-based controllers. These controllers will be used for boundary constrained granular swarms to form desired shapes and morph between shapes in both 2D and 3D simulated systems and experimental systems. Moreover, this thesis will explore the use of grasping metrics for boundary-constrained granular swarms. The Ferrari Canny metric, a well-established tool for assessing grasp quality in robotic manipulators, is utilized to evaluate the system’s grasp performance. This thesis will also demonstrate the application of this metric for boundary-constrained swarms to find the optimal angle of approach for the system to grasp a target object.
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Title: Understanding the Impact of Age and Gender Demographic Similarity in Assessment Center and Individual Assessment Ratings
Creator: Levin, Kelly
Date: 2023
Description: Organizations have become increasingly reliant on the use of assessment centers and individual assessments when making hiring decisions....
Show moreOrganizations have become increasingly reliant on the use of assessment centers and individual assessments when making hiring decisions. However, there has been relatively limited research on the prevalence of subgroup differences with the use of these tools. As such, this study investigated the individual characteristics of gender and age in both assessment centers and individual assessments. Specifically, the study examined how candidate gender and age, as well as the dyadic “match” between assessor-assessee gender and age impacted assessors’ hiring recommendations. Results from this research partially supported the hypothesized outcomes. Both female and younger candidates were rated more favorably on the overall assessment center recommendation. However, neither candidate gender or age had a significant impact on individual assessment recommendations. Further, demographic similarity had little effect on overall recommendations in both ACs and individual assessments. Implications and avenues for future research are discussed.
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Title: Linear Systems Analysis of Molecular Dynamics
Creator: Nicholson, Stanley Anselm
Date: 2023
Description: Most proteins reduce the complexity of atomic motion to stable and coherent structures. Molecular dynamics (MD) has provided swaths of...
Show moreMost proteins reduce the complexity of atomic motion to stable and coherent structures. Molecular dynamics (MD) has provided swaths of trajectory data of proteins. We analyze these trajectories using classical stochastic signal analysis, well established and utilized by engineers. Linear systems analysis operates to uncover linearities given an input and output signal. The coherence function says an input and output are linearly related if and only if the coherence equals one. Analyzing protein motion in the frequency domain allows us to extract a frequency function relating the modes of motion as determined by atomic power spectra. Motivated by biochemistry, we analyze classical interactions like hydrogen bonds and salt bridges and find they act like a linear system, or effective spring. We test our analysis on two protein systems: crambin and the Mu Opioid Receptor (MOR). We extend our results to all pairwise interaction and determine coherent communities of atoms within the MOR. We present various community detection algorithms and demonstrate their validity using common metrics in MD. Identifying rigid and tightly correlated regions of the protein offers great potential in coarse graining protein structure and understanding protein motion.
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Title: A Novel Explainability Approach For Spectrum Measurement Insight
Creator: Nagpure, Vaishali
Date: 2023
Description: Spectrum is an extremely valuable natural resource in high demand. Although the spectrum has been fully allocated, there is no comprehensive...
Show moreSpectrum is an extremely valuable natural resource in high demand. Although the spectrum has been fully allocated, there is no comprehensive method for understanding about how it’s being used. Spectrum measurements are highly complex spatiotemporal data sets that play a key role in understanding spectrum use and require very specialized domain information for understanding. To leverage existing and future spectrum measurements to the fullest extent, it is necessary to have a systematic way to connect them to the contextual information that helps provide meaning to the data. To analyze and interpret the measurements, a variety of contextual information is needed. This research develops a novel approach for spectrum measurement understanding that unifies five years of wideband spectrum measurement summary data together with relevant contextual information from a variety of sources in a spectrum knowledge graph. Both quantitative and qualitative information is modeled and implemented on a Neo4j graph database platform. This modeling formalizes the relationships that help spectrum stakeholders “connect the dots” and provide deeper understanding of RF spectrum utilization. The knowledge graph can be queried to extract a wide variety of insights thus making spectrum knowledge more widely accessible to a variety of stakeholders.
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Title: Pain and Life Satisfaction: The Role of Emotional Support and Social Participation in Adults with Pediatric-Onset Spinal Cord Injury
Creator: Oh, Alison J.
Date: 2023
Description: Individuals who acquire a spinal cord injury (SCI) during their pediatric years are unique from individuals who acquire an SCI during...
Show moreIndividuals who acquire a spinal cord injury (SCI) during their pediatric years are unique from individuals who acquire an SCI during adulthood due to the heightened risks for developing secondary health conditions and chronic pain. These concerns may significantly impede developmental milestones and experiences, such as social participation, that may decrease life satisfaction. Thus, research on pain characteristics (e.g., frequency of pain, duration of pain, level of current pain, and level of general pain) alongside the role of emotional support and social participation on life satisfaction in adults with pediatric-onset SCI is needed. This study sample consisted of 205 individuals with pediatric-onset SCI who were former patients at pediatric hospitals in three metropolitan cities. Participants were individuals who were 19 years of age or older at the time of the interview, with the age of injury at 18 years or prior. Associations between demographic, pain, and injury characteristics, emotional support, social participation, and life satisfaction were assessed via bivariate Pearson correlations and a 3-block hierarchical multiple linear regression with LS as the primary outcome. Although pain characteristics and emotional support were not associated with life satisfaction among adults who sustained a pediatric-onset SCI, social participation was positively associated with life satisfaction. These findings suggest that clinicians should evaluate various pain characteristics and highlight the role of social participation when treating individuals with SCI.
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Title: Examination of Power Ultrasound and Organic Acid-based Hurdle Technology in the Reduction of Salmonella Enterica on Peaches and Apples
Creator: Mathias, Hina Valida
Date: 2023
Description: Fresh produce includes fruit matrices like whole peaches and apples that are minimally processed and are a popular choice among different...
Show moreFresh produce includes fruit matrices like whole peaches and apples that are minimally processed and are a popular choice among different types of demographics because of their nutrition content and health benefits. However, there have been increasing pathogen outbreaks in these matrices over the past few decades, which are majorly rooted in cross contamination either due to poor handling pre and post processing or the insufficient reduction of the pathogen at processing by the applied hurdle technology. While chemical sanitizers are a popular option in the food industry, the awareness and demand for green consumerism and sustainability have created a need for research to determine the efficacies of organic acids and non-thermal technologies like power ultrasound in the reduction of different pathogens on different food matrices. This study focusses on the S. enterica reduction capabilities of three organic acids – citric, malic, and lactic alone and in combination with 40 kHz power ultrasound at 1, 2 and 5% for treatment times of 2, 5 and 10 min on whole yellow peaches and gala apples. Peaches and apples were spot inoculated with a four-strain cocktail of S. enterica, resulting in 9 log CFU/fruit. Post air drying for 1 h, the fruits were treated with water, 1, 2, or 5% citric, lactic, or malic acid for 2, 5 or 10 min with and without power ultrasound treatment at 40 kHz. The population of S. enterica on the fruits was enumerated before and after treatment. Three independent trials with triplicate samples were performed for each condition. Population differences were evaluated via Student's t-test and ANOVA; p<0.05 was considered significant. The initial level of inoculum ranged from 8.67 ± 0.41 to 8.20 ± 0.26 log CFU/peach and 7.28 ± 0.60 to 8.17 ± 0.37 log CFU/apple in peaches and apples, respectively. Water treatments showed pathogen reduction as high as 1.22 log CFU/peach and 1.02 log CFU/apple. Citric acid treatments on peaches showed significant pathogen reduction at higher time increments at 5% with a reduction of S. enterica as high as 2.24 log CFU/peach after 10 min. Malic acid showed the highest recorded log reduction in peaches at 5% and 10 min being 4.20 log CFU/peach (n=1/9, samples above the enumeration limit) and apples at 5% and 5 min being 3.71 log CFU/apple (n=4/9, samples above the enumeration limit) both in combination with an ultrasound. Lactic acid, unlike the other two organic acids, showed a pathogen reduction of over 3 log CFU/fruit at 2% after 10 min, with the highest pathogen reductions of 3.76 log CFU/peach and >3.62 log CFU/apple at 5% and10 min. There was no particular trend with significant enhancement of pathogen reduction either with time increment or the addition of ultrasound and varied with the varying acids, treatment conditions and fruit matrices.
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Title: Cities on the Move: Envisioning Cityscape in the Autonomous Vehicle Era
Creator: Lee, Hyo Eun
Date: 2023
Description: As cities have developed in response to a rapidly changing environment since the industrial revolution, a variety of circumstances and issues...
Show moreAs cities have developed in response to a rapidly changing environment since the industrial revolution, a variety of circumstances and issues have arisen. In cities, technological development and the rise of private automobiles have been related to urban sprawl, traffic congestion, environmental degradation, and mobility inequalities. Currently, autonomous vehicles are bringing a paradigm shift in mobility as technological innovations accompany the fourth industrial revolution. As cities undergo renewal through new mobility, recent developments in driverless technologies should be considered for their long-term impact on the built environment. The purpose of this thesis is to propose a design, along with a set of scenarios, for a transportation hub in the era of autonomous vehicles to address today's complex mobility requirements. Through bringing together existing case studies, research on autonomous vehicles, and drawing conclusions regarding the relationship between mobility and urban landscapes, this thesis explores how autonomous vehicles will affect the future built environment in a set of timelines. Considering the future transportation hub will require programs and infrastructure to support autonomous vehicles, this thesis also provides a vision of the future of transportation modes and how they interact. Finally, a transportation hub design model and an automation city model for the AV era will be proposed.
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Title: Analysis on the Persisting Effects of Redlining on Green Infrastructure in Chicago Neighborhoods - Neighborhood Map files
Creator: Meyer, Joel, Eshraghi, Amirreza
Date: 2023
Description: This compressed collection of map files constitutes data used in "Analysis on the Persisting Effects of Redlining on Green Infrastructure in...
Show moreThis compressed collection of map files constitutes data used in "Analysis on the Persisting Effects of Redlining on Green Infrastructure in Chicago Neighborhoods", published in SoReMo, March 2023 (DOI: https://doi.org/10.18409/soremojournal.v3i1.221). The report looks at “redlining” maps produced by the Home Owners’ Loan Corporation (HOLC) to analyze the current green infrastructure levels in various neighborhoods of Chicago.
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Title: Views on Ethical Issues in Research Labs: a University-Wide Survey
Creator: Laas, Kelly, Taylor, Stephanie, Miller, Christine Z, Brey, Eric M, Hildt, Elisabeth
Date: 2021
Description: Full survey used for "Views on Ethical Issues in Research Labs" published in the journal Accountability in Research: Policies and Quality...
Show moreFull survey used for "Views on Ethical Issues in Research Labs" published in the journal Accountability in Research: Policies and Quality Assurance in 2021. This survey was completed in 2017.
Sponsorship: National Science Foundation
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Collection: Accountability in Research: Policies and Quality Assurance

Title: Mentions of Ethics Codes in Social Media: A Twitter Analysis
Creator: Laas, Kelly, Hildt, Elisabeth, Wu, Ying
Date: 2022, 2022-01-03
Publisher: Springer, Cham
Collection: Codes of Ethics and Ethical Guidelines: Emerging Technologies and Changing Fields

Title: An Introduction to the Societal Roles of Ethics Codes
Creator: Laas, Kelly, Davis, Michael, Hildt, Elisabeth
Date: 2022, 2022-01-03
Publisher: Springer, Cham
Description: In this collected volume, we are interested in the roles of ethics codes and ethical guidelines in professions in which research and...
Show moreIn this collected volume, we are interested in the roles of ethics codes and ethical guidelines in professions in which research and innovation play an important role and where emerging technologies bring about considerable, sometimes fast-paced change.
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Collection: Codes of Ethics and Ethical Guidelines: Emerging Technologies and Changing Fields

Title: Informed Consent in Digital Data Management
Creator: Hildt, Elisabeth, Laas, Kelly
Date: 2022, 2022-01-03
Publisher: Springer, Cham
Description: This article discusses the role of informed consent, a well-known concept and standard established in the field of medicine, in ethics codes...
Show moreThis article discusses the role of informed consent, a well-known concept and standard established in the field of medicine, in ethics codes relating to digital data management. It analyzes the significance allotted to informed consent and informed consent-related principles in ethics codes, policies, and guidelines by presenting the results of a study focused on 31 ethics codes, policies, and guidelines held as part of the Ethics Codes Collection. The analysis reveals that up to now, there is a limited number of codes of ethics, policies, and guidelines on digital data management. Informed consent often is a central component in these codes and guidelines. While there undoubtedly are significant similarities between informed consent in medicine and digital data management, in ethics codes and guidelines, informed consent-related standards in some fields such as marketing are weaker and less strict. The article concludes that informed consent is an essential standard in digital data management that can help effectively shape future practices in the field. However, a more detailed reflection on the specific content and role of informed consent and informed consent-related standards in the various areas of digital data management is needed to avoid the weakening and dilution of standards in contexts where there are no clear legal regulations.
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Collection: Codes of Ethics and Ethical Guidelines: Emerging Technologies and Changing Fields

Title: Simulation and Experimental Testing of High-Gradient Dielectric Disk Accelerating Cavities
Creator: Weatherly, Sarah K.
Date: 2022
Description: Structure-based wakefield acceleration can be accomplished using either Collinear Wakefield Acceleration (CWA) where the drive beam and the...
Show moreStructure-based wakefield acceleration can be accomplished using either Collinear Wakefield Acceleration (CWA) where the drive beam and the witness beam are located on the same beamline or Two Beam Acceleration (TBA) where the RF power generated by the drive beam is extracted and transferred to the witness beam line. A Dielectric Disk Accelerator (DDA) is an accelerating structure that is utilized by TBA that uses dielectric disks to improve the structure's shunt impedance and accelerate the witness beam. Dielectric based accelerators studied in this thesis are X-Band structures (have a working frequency between 8 and 12 GHz) that can use any pulse length but in this study utilize short (<20 ns) traveling wave pulses. Short pulse lengths are used to decrease breakdown probability and allow for a large gradient. DDAs have a higher group velocity and a larger shunt impedance compared to traditional metallic accelerating structures while maintaining a large accelerating gradient. DDAs are a strong candidate for use in the Argonne Wakefield Accelerator’s 500 MeV Demonstrator. Recent experimental results of a clamped single cell structure demonstrated a >100 MV/m accelerating gradient with no evidence of breakdown in the RF volume. Additional structures, including a brazed single cell model and a multicell structure, have been designed and are now being fabricated for high power testing.
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Title: A SCALABLE AND CUSTOMIZABLE SIMULATION PLATFORM FOR ACCURATE QUANTUM NETWORK DESIGN AND EVALUATION
Creator: Wu, Xiaoliang
Date: 2021
Description: Recent advances in quantum information science enabled the development of quantum communication network prototypes and created an opportunity...
Show moreRecent advances in quantum information science enabled the development of quantum communication network prototypes and created an opportunity to study full-stack quantum network architectures. The scale and complexity of quantum networks require cost-efficient means for testing and evaluation. Simulators allow for testing hardware, protocols, and applications cost-effectively before constructing experimental networks. This work develops SeQUeNCe, a comprehensive, customizable quantum network simulator. We have explored SeQUeNCe for quantum communication network evaluation. We use SeQUeNCe to study the performance of the quantum network with different hardware and applications. Additionally, we extend SeQUeNCe to a parallel discrete-event simulator by using the message passing interface (MPI). We comprehensively analyze the benefit and overhead of parallelization. The parallelization technique significantly increases the scalability of SeQUeNCe. In the future, we would like to improve SeQUeNCe in three aspects. First, we plan to continue reducing overhead from parallelization and increasing the scalability of SeQUeNCe. Second, we plan to investigate means to model quantum memory, entanglement protocols, and control protocols to enrich simulation models in the SeQUeNCe library. Third, we plan to integrate hardware with SeQUeNCe to enable high-fidelity analysis.
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Title: Development of MIITRA T1w, DTI and FOD templates of the older adult brain in a common space
Creator: Wu, Yingjuan
Date: 2022
Description: Human brain atlases play an important role in neuroimaging studies and are commonly used as references for spatial normalization, tissue...
Show moreHuman brain atlases play an important role in neuroimaging studies and are commonly used as references for spatial normalization, tissue segmentation, automated brain parcellation, seed selection for functional connectivity analyses and fiber-tracking, or standards for algorithm evaluation. A brain atlas typically consists of brain templates of different imaging modalities in a common space and semantic labels that delineate brain regions according to the characteristics of the underlying tissue.High-quality T1-weighted (T1w) and diffusion tensor imaging (DTI) brain templates that are representative of the individuals under study enhance the accuracy of template-based neuroimaging investigations, and when they are also located in a common space they facilitate optimal integration of information on brain morphometry and diffusion characteristics. However, such multimodal templates have not been constructed for the brain of older adults. This thesis introduced an iterative method for construction of multimodal T1w and DTI templates that aims at maximizing the quality of each template separately as well as the spatial matching between templates. The performance of the proposed method was evaluated across iterations and was compared to the performance of state-of-the-art multimodal template construction approaches based on multichannel registration. Using the proposed method, along with other recently developed techniques, high-quality T1w and DTI templates of the older adult brain were developed in a common space at 0.5mm resolution for the MIITRA atlas. In this thesis, the new templates were compared to other available templates in terms of the image quality, inter-subject and inter-modality spatial normalization accuracy achieved when used as a reference, and the representativeness of the older adult brain. Furthermore, as fiber orientation distribution (FOD) model is capable of resolving intravoxel heterogeneity, which overcomes the limitations of the DTI model especially in regions with complex neuronal microarchitecture, FOD template is in high demand to facilitate FOD-based, fixel-based analyses, white matter connectivity studies and white matter parcellations. In this thesis, several FOD template construction methods were compared and a FOD template was developed at 0.5mm resolution for the MIITRA atlas. Overall, the present work brought new insights into multimodal template construction, conducted a thorough, quantitative evaluation of available multimodal template construction methods, and generated much-needed high quality T1w, DTI and FOD templates of the older adult brain in a common space with 0.5mm resolution.
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Title: AN EXPLORATION INTO THE EFFECTS OF CHROMATIN STRUCTURAL PROTEINS ON THE DYNAMICS AND ENERGETIC LANDSCAPE OF NUCLEOSOME ARCHITECTURES
Creator: Woods, Dustin C
Date: 2022
Description: Comprised of eight core histones wrapped around at least 147 base pairs of DNA, nucleosomes are the fundamental unit the chromatin fiber from...
Show moreComprised of eight core histones wrapped around at least 147 base pairs of DNA, nucleosomes are the fundamental unit the chromatin fiber from which long arrays are built to compact genetic information into the cell nucleus. Structural proteins, such as linker histones (LH) and centromere proteins (CENP), interact with the DNA to dictate the exact architecture of the fiber which can directly influence the regulation of epigentic processes. However, the mechanisms by which structural proteins affect these processes are poorly understood. In this thesis, I will explore the various way in which LHs and CENP-N affect nucleosome and, by extension, chromatin fiber dynamics. First, I present a series of simulations of nucleosomes bound to LHs, otherwise known as chromatosomes, with the globular domain of two LH variants, generic H1 (genGH1) and H1.0 (GH1.0), to determine how their differences influence chromatosome structures, energetics and dynamics. These simulations highlight the thermodynamic basis for different LH binding motifs, and details their physical and chemical effects on chromatosomes. Second, I examine how well the findings above translate from mono-nucleosomes to poly-nucleosome arrays. I present a series of molecular dynamics simulations of octa-nucleosome arrays, based on a cryo-EMstructure of the 30-nm chromatin fiber, with and without the globular domains of the H1 LH to determine how they influence fiber structures and dynamics. These simulations highlight the effects of LH binding on the internal dynamics and global structure of poly- nucleosome arrays, while providing physical insight into a mechanism of chromatin compaction. Third, I took a brief departure from LHs to study the effects that the centromere protein N (CENP-N) has on the poly-nucleosome systems. I present a series of molecular dynamics simulations of CENP-N and di-nucleosome complexes based on cryo- EM and crystal structures provided by Keda Zhou and Karolin Luger. Simulations were conducted with nucleosomes in complex with one, two, and no CENP-Ns. This work, in collaboration with the Karolin Luger Group (University of Colorado – Boulder) and the Aaron Straight Group (Stanford University), represents the first atomistic simulations of this novel complex, providing the foundation for a plethora of future research opportunities exploring centromeric chromatin the effect that its structure and dynamics have on epigenetics. Lastly, I return to the chromatosome to study how DNA sequence affects the free energy surface and detailed mechanism of LH transitions between binding modes. I used umbrella sampling simulations to produce PMFs of chromatosomes wrapped in three different DNA sequences: Widom 601, poly-AT, and poly-CG. This work, my final in the series, represents a culmination of my studies furthering the understanding of biophysical phenomena surrounding LHs and how they can be extrapolated towards epigentic mechanisms. I was able to report on the first PMFs illustrating a previously unknown transition and describe the transition mechanism as it depends on DNA sequence.
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Title: The Studio Practice for Sustainable (Craft) Production
Creator: Werdhaningsih, Hendriana
Date: 2022
Description: Craft market demand globally is rising. On the other hand, the domination of economic goals in craft production is threading the social system...
Show moreCraft market demand globally is rising. On the other hand, the domination of economic goals in craft production is threading the social system and the environment. Craft production facts do not represent the sustainable development principles that should be a central concept for this age. Design as practice and method had not yet correctly facilitated craft production to embrace the harmony of the social, environmental, and economic systems. Believing that studio is a core design practice, this research investigated studio practice through interviews, field research, and action research conducted in Indonesia and the US. It developed a model called Studio Practice for Sustainable (Craft) Production, the SP2 Model. The Model helps designers, the crafts community, and stakeholders ensure their role in the studio practice and determine their goals for sustainable development. The SP2 Model offers alternative practical solutions in craft production, contributes to polycentric discourse, and designs interventions in sustainable development models.
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Title: ESTIMATING PM2.5 INFILTRATION FACTORS FROM REAL-TIME OPTICAL PARTICLE COUNTERS DEPLOYED IN CHICAGO HOMES BEFORE AND AFTER MECHANICAL VENTILATION RETROFITS
Creator: Wang, Mingyu
Date: 2021
Description: PM2.5 are fine inhalable particles that are 2.5 micrometers or smaller in size. Indoor PM2.5 consists of outdoor PM2.5 (ambient PM2.5) that is...
Show morePM2.5 are fine inhalable particles that are 2.5 micrometers or smaller in size. Indoor PM2.5 consists of outdoor PM2.5 (ambient PM2.5) that is infiltrated into the indoor environment and indoor generated PM2.5 (non-ambient PM2.5). As people spend nearly 90% of their lifetimes indoors, with most of that time in their homes, PM2.5 exposure in homes results in severe health effects such as asthma. One strategy increasingly being used to dilute air pollutants generated indoors and improve indoor air quality (IAQ) in homes is the introduction of mechanical ventilation systems. However, mechanical ventilation systems also have the potential to introduce more ambient PM2.5 than relying on infiltration alone, although limited data exist to demonstrate the magnitude of impacts in occupied homes. The objective of this paper is to estimate the infiltration factor (Finf) of PM2.5 before and after installing mechanical ventilation systems in a subset of occupied homes. The data source utilized comes from the Breathe Easy Project, a more than 2-year-long study conducted in 40 existing homes in Chicago, IL aiming to explore the effects of three different types of mechanical ventilation system retrofits on IAQ and asthma. An automated algorithm was developed to remove indoor PM2.5 peaks in time-series data collected from optical particle counters deployed inside and outside of each home. The Finf was estimated using the resulting indoor/outdoor ratio with indoor peaks removed. Before mechanical ventilation retrofits, the weekly median Finf was 0.29 (summer median = 0.41, fall median = 0.26, winter median = 0.29, spring median = 0.30); after mechanical ventilation retrofits, the median Finf was 0.34 (winter median= 0.28, spring median = 0.45, summer median = 0.54, fall median = 0.20). Differences in Finf between pre- and post-intervention periods were not statistically significant (p = 0.23 from Wilcoxon signed rank tests). The median PM2.5 infiltration factor increased ~22% (from 0.27 to 0.33) with the installation of balanced ventilation systems with energy recovery ventilators (ERV), although differences were not statistically significant (Wilcoxon signed rank p = 0.35). The median PM2.5 infiltration factor decreased ~4% (from 0.28 to 0.27) after installing intermittent CFIS systems, which intermittently supply ventilation air through the existing central air handling units and associated filters (which were upgraded to a minimum of MERV 10 in all CFIS homes), although differences were not statistically significant (Wilcoxon signed rank p = 0.24). The median PM2.5 infiltration factor increased ~26% (from 0.35 to 0.44) with the installation of continuous exhaust-only systems, and differences were significant (Wilcoxon signed rank p = 0.04). These results suggest that the filtration mechanisms used on the CFIS and balanced systems were adequate for maintaining similar distributions of Finf values pre- and post-interventions whereas the increased delivery of outdoor air via the building envelope by exhaust-only systems significantly increased Finf following retrofits.
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Title: Architecture as a Communicator of Values and Identity Spaces for Public Safety and Community Benefits
Creator: Waidele Arteaga, Nicolas
Date: 2022
Description: Urban segregation, violence, and crimes are linked to drug trafficking. El Castillo Social Factory is an urban strategy that aims to recover...
Show moreUrban segregation, violence, and crimes are linked to drug trafficking. El Castillo Social Factory is an urban strategy that aims to recover the El Castillo neighborhood and prevent drug trafficking from advancing, understanding that police action is necessary but insufficient.This neighborhood is located on the southern periphery of Santiago in a commune called La Pintana and aspires to make its neighborhoods “more livable, healthy, and economically viable.” This proposal explores how investing in civic commons can make these goals a reality. First, it is essential to increase the presence of the State, strengthening existing services and adding new ones, with a focus on the care of children and young people. The second is to recover vacant lots and public spaces in poor condition or deteriorated through an “urban acupuncture” strategy based on the construction of many small or medium-sized projects. Art and sports are fundamental, allowing us to protect children and young people and offer them horizons of recreation and hope. The public buildings, institutions, land, water bodies, and infrastructure inherited from earlier generations are ready for us to see anew—as a robust network of civic assets ready to be activated for the current needs, desires, and dreams of all the people who share and shape them. El Castillo Social Factory offers a fresh look at our community anchors and the vibrant hubs our public spaces can become when we invest in collective urban life. Its vision focuses on positive transformation at the architectural scale—where personal experience and aspirations meet broad, long-range planning efforts—to spark the imagination and spur us to work together toward realizing the abundant potential of what we hold in common.
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Title: A New Control and Decision Support Framework To Avoid Fast-Evolving System Collapse and Cascading Failure
Creator: Guha, Bikiran
Date: 2022
Description: The modern power system is a vast and incredibly complex network with a very large number of equipment operating round the clock to reliably...
Show moreThe modern power system is a vast and incredibly complex network with a very large number of equipment operating round the clock to reliably transport electricity from generators to consumers. However, factors such as aging and faulty equipment, extreme and unpredictable weather, cyber attacks and increasing amounts of unpredictable renewable generation have made it increasingly vulnerable to cascading failure and wide-area collapse. Therefore, a lot of work has been done over the years on cascading failure vulnerability analysis and mitigation. However, to the best of our knowledge, the existing literature on this topic focus on preventive analysis and mitigation, mostly from a planning perspective. There is a lack of decision support schemes which can take real-time preventive action when the system becomes vulnerable to cascading failure, while taking into account the various dynamics and uncertainties involved in these types of failures. The only defense under these situations are pre-designed emergency control schemes. However, they are only effective against known vulnerabilities and can make matters worse if not accurately designed and calibrated.This research work has proposed a novel wide-area monitoring protection and control (N-WAMPAC-20) framework designed to make decisions in real-time to assess the vulnerabilities of the system (when a disturbance happens) and to implement mitigation actions, if necessary. The main contributions of this dissertation focus on the disturbance monitoring, real-time control and decision making aspects of this framework. The proposed framework has been divided into two major parts: an offline part and an online part. The offline part continuously runs extreme contingency analysis in the background (using combined dynamics and protection simulators) to generate elements which can assess system vulnerabilities and suggest suitable mitigation actions, if necessary. In this regard, a novel load shedding adjustment scheme is also proposed, which has been shown to be effective against a variety of fast-evolving cascading failure scenarios. The online part consists of real-time disturbance monitoring and decision-making components. The disturbance monitoring component focuses on real-time fault detection and location. If a fault has been identified and located, the real-time decision making component determines the vulnerability of the system, by consulting with the elements designed offline. If vulnerabilities are identified, targeted mitigation actions are implemented. The design and applicability of a prototype of N-WAMPAC-20 has been presented using a case of voltage collapse and a case of wide-area loss of synchronization on a synthetic model of the Texas grid.
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