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Engineered Interfaces for Enhanced Transient Liquid Phase Bonding in Electronics Assembly
No full textGrowing applications in transportation make power density a key optimization target in the power electronics industry. More power in a shrinking environment leads to high heat flux and junction temperatures that damage silicon-based switching devices. Temperatures approaching 175℃ can result in false triggering of the device’s activated state, resulting in short circuits. Developing wide bandgap semi-conductors, such as gallium nitride and silicon carbide, are less susceptible to this complication as the energy from elevated temperature is a smaller fraction of what would be required to trigger the device. These devices are projected to function reliably in environments of up to 800℃. Thus far, such applications have been held back by packaging and passives technology. This work seeks to advance the knowledge and applicability of copper-tin transient liquid phase bonding technology by accelerating, simplifying and enhancing the process. Transient liquid phase bonding is a diffusion-based technology, highly dependent on length for processing speed. In electronics, thin bond lines lead to reliability concerns and process complications. Utilizing patterned copper substrates, the effective bond length can be maintained while the bond line thickness increases. Such a structure resembles a unidirectional lamina as defined by composite theory, affording the opportunity to tune bond properties by controlling the shape and density of substrate patterns. In this work copper-tin transient liquid phase bonding is demonstrated in atmosphere, using SAC305 solder on nanowire populated substrates. Demonstrations show up to 99.78% acceleration in the rate of bonding compared to a substrate without any surface structures. The bonding prosses is then refined for repeatability. Thermal and electrical conductivities are examined, and bond stability is evaluated using high temperature storage testing. Results show an average shear strength of 29.4 MPa that does not change with any statistical significance over 72 hours at 175℃. Additionally, thermal conductivity measurements demonstrate thermal conductivity up to 89.9 W/mK
Workplace Retaliation and the Intersection of Protected Conduct and Job Performance
No full textA host of statutory schemes seek to ensure equal employment opportunities in the United States by eradicating workplace discrimination (“EEO laws”). Consider two foundational pillars necessary for these EEO laws to strike the desired balance between individual rights and workplace efficiency. First, employees require robust protection from retaliation if they engage in protected conduct—for example, by reporting perceived discrimination. Second, employers can—and ideally, should—make employment decisions based on how an employee performs the job.
The interests in robust protection and performance-based decision-making serve the purposes of our EEO laws and are well-established. Rarely do they conflict (to the contrary, they oftentimes complement one another). Tension arises when the putative protected conduct comes from an employee whose job duties explicitly include tasks like identifying, reporting, and remedying concerns about the company’s legal compliance (“EEO employee”).
Courts have struggled with how to handle situations like this. To date, the response has been to either accept or reject the “Manager Rule.” The Manager Rule provides that an employee who voices concern about conduct perceived to be unlawful as part of the employee’s job duties does not engage in protected conduct (and thus cannot maintain a retaliation claim), unless the employee “steps outside” of what the job normally entails in reporting the concern.
Existing scholarship has focused largely on statutory purpose and public policy. This Article seeks to fill a void by proposing a new analytical approach: the “Performance Test.” Part II outlines retaliation claims, generally, by examining the ubiquitous burden- shifting framework for EEO claims, the relevant statutory Part III explores judicial treatment of retaliation claims when putative protected conduct and job performance intersect, with an assessment of the faulty analysis employed by both pro- and anti-Manager Rule jurisdictions. Part IV then details the proposed Performance Test as
The Illusory Privilege Against Self-Incrimination
No full textThis Note addresses the insufficiency of the current system in protecting criminal defendants’ privilege against self-incrimination. Part II will outline the background legal principles of the issue, including the privilege against self-incrimination, the presumption of innocence, and the no-impeachment rule. This part will also address the Supreme Court’s sole judicial exception to the no-impeachment rule as laid out in Peña-Rodriguez v. Colorado. Part III will address the statistical significance of juror bias against criminal defendants who invoke the privilege, highlight the widespread nature of the bias, and argue that the procedural safeguards currently in place are insufficient to protect
Innocent Until Proven Guilty, Disenfranchised All the Same: Hidden Voter Suppression Within American Jails
No full textJails throughout the United States hold thousands of legally eligible voters who have not been convicted of a crime While those convicted of felonies are often statutorily disenfranchised, pretrial detainees retain their civil rights—including the right to vote. In theory, this should guarantee them a voice. In practice, pretrial detention operates like a legal disqualification. Without meaningful enforcement mechanisms, the right to vote becomes hollow.
This Comment argues that implementing a national standard based on the proactive policies of Massachusetts and Nevada will ensure accessible voting for pretrial detainees. To build that argument, this Comment first explores the low level of protection provided by existing Supreme Court precedent. It will then examine how logistical obstacles at the state level—such as voter registration rules and absentee ballot procedures—contribute to pretrial detainees’ disenfranchisement. Finally, this Comment will highlight reforms implemented in a handful of states and argue for a federal framework that ensures voting access for all eligible voters, regardless of detention status
P-E-S-T-O-G-O: This Third Circuit Ruling Has Got to Go, A Deep Dive into the Circuit Split Issue of FIFRA Preemption
No full textThe American public is becoming increasingly concerned about pesticides. From “forever chemicals” to environmental justice concerns, public awareness of pesticide issues is only becoming more prevalent. However, one pesticide has seized public attention in a significant way. Glyphosate, the active ingredient in Monsanto’s “Roundup” and other commercial pesticides has been the subject of heated debate in federal courtrooms across the nation. The rising controversy over glyphosate has even led some jurisdictions to attempt to ban or restrict the use of the product altogether.
While the scientific studies and legal definitions about glyphosate and its cancer link are inconsistent, a reasonable consumer may be frightened that the pesticide in their food is harmful and can cause cancer. In fact, so many people have become frightened about glyphosate exposure that thousands of plaintiffs across the country have brought state law failure-to-warn claims against Bayer based on their glyphosate exposure. Three of these cases have taken on paramount importance because they have created a circuit split based on whether or not these claims are expressly preempted by the Federal Insecticide Fungicide and Rodenticide Act.
This article will address the legal background of the circuit split, what the individual cases held, and why the Supreme Court should affirm the rulings of the Ninth and Eleventh Circuits. Because the Third Circuit failed to properly apply FIFRA’s statutory scheme and created concerning precedent for all express preemption cases, when the Supreme Court takes up the issue to resolve the split, it should overturn the Third Circuit’s decision and hold that FIFRA does not expressly preempt these state law failure-to-warn claims
Creating a Website to Introduce and Inform Local Apparel Businesses’ Sustainability to Fayetteville College Students
Get PDFFast fashion has increased clothing consumption and waste, contributing to severe environmental consequences. Large retailers rapidly produce garments to keep up with microtrends, leading to consumer waste and unsustainable habits. This thesis aims to educate University of Arkansas students about fast fashion’s environmental impact and promote sustainable shopping practices. To achieve this goal a website will be created for educational purposes and will provide information on sustainability and fast fashion as well as local sustainable apparel businesses in Northwest Arkansas. The research draws from consumer behavior studies, business sustainability models, and the effectiveness of educational interventions on shopping habits. The website will offer accessible, engaging content to educate and encourage students to make eco-conscious decisions. The project\u27s success will be determined by the accessibility of the website. Ultimately, the project aims to bring awareness about fashion sustainability to the local community and inspire long-term changes in consumer behavior
All Mud in the End: Exploring Registration Between Handcraft and Digital Craft Through Ceramic 3D Printing
Get PDFThe goal of this research was to investigate the possible interconnections between handcrafted objects and digital fabrication technologies, specifically in ceramic 3D printing workflows. Digital fabrication tools have advanced rapidly in recent years, raising questions about the role handcraft can still play in the making of objects and buildings. While many artistic endeavors have investigated how far digital technology can be pushed, this study was focused on bringing handcrafted objects back into the conversation. Specifically, it sought to understand how irregular, handcrafted objects may be registered in the digital space and then used in 3D printing processes.
The study used 3D-printed and wheel thrown ceramics to investigate the issue of digital registration of physical objects. Registration here means aligning the physical objects with the digital; I created clay vessels on the pottery wheel, scanned them using photogrammetry technology, and then aligned them in the digital modeling environment. After registering the form, I used a clay 3D printer to interact with the handcrafted object through surface ornamentation and additional volume creation. Future large-scale creations, such as 3D printed buildings, will need to interact with irregular, handcrafted parts – printed concrete walls may need to align with wooden beams, traditionally framed walls, or irregular topography. The forms resulting from these experiments serve as a small-scale guidebook to the intersection of handcraft and digital craft in ceramic 3D printing.
This paper discusses and analyzes the successes and challenges of scanning objects, modeling prints, and printing on a handmade object
Achieving Flexible Fairness and Privacy in Federated Learning
Get PDFHaving access to large, high-quality datasets is crucial for training machine learning models that achieve satisfactory performance. Unfortunately, it is common that a single entity (e.g., mobile device or organization) does not have access to such datasets due to monetary or resource constraints. Traditional machine learning requires that all training data reside in a centralized location during the entire duration of model training, however, in many circumstances it is difficult or even impossible (e.g., due to governmental regulations) for multiple parties to combine their data to meet this constraint. Federated learning is a machine learning paradigm that facilitates the joint training of a model by multiple parties under the organization of a central server without the parties explicitly having to share their private local data. Due to its potential for solving challenges in domains such as IoT and healthcare, federated learning research has received significant interest especially in the areas of efficiency and optimization. Additionally, due to rising demands for increased privacy protections and fairness, research into trustworthy federated learning has grown in popularity. Despite progress over the past few years, several challenges still remain as open problems in relation to trustworthy federated learning.
The goal of this dissertation is to address a major pitfall of current trustworthy federated learning publications -- flexibility. Often in proposed fair and/or private federated learning works, all clients are required to use the same fairness metric or privacy level which over-constrains the federation participants. In this dissertation, we propose to solve overlooked problems in trustworthy federated learning, such as: 1) how can clients independently choose a demographic fairness metric to enforce locally without greatly affecting the global model\u27s final accuracy, 2) can an optimization function for federated learning be devised such that it can achieve multiple different client-level fairness definitions, and 3) is it possible to devise a federated learning algorithm that allows clients to update their local privacy level as needed without requiring full model retraining? To solve these questions, in this dissertation we performed the following:
1) We developed Fair HyperNetworks (FHN) -- a personalized federated learning algorithm based on hypernetworks that allows each client in the federation to choose which type of demographic fairness to enforce on their local model. FHN ensures that different demographic groups receive fair treatment while maintaining high accuracy for each client.
2) We proposed Uncertainty-based Distributive Justice for Federated Learning (UDJ-FL), a flexible federated learning framework that can achieve multiple distributive justice-based client-level fairness metrics. UDJ-FL, by utilizing techniques inspired by fair resource allocation, in conjunction with performing aleatoric uncertainty-based client weighing, is able to achieve egalitarian, utilitarian, Rawls’ difference principle, or desert-based client-level fairness.
3) We constructed Flexible Local Differential Privacy for Federated Learning (FLDP-FL), a flexible architecture for federated learning based on influence functions that allows clients to change their privacy guarantees post-training without requiring the entire federated learning process to be repeated
Agronomics
No full textAgronomics is a braided collection of short stories that weaves the lives of the people who populate a small town in Northern Indiana Each character struggles with their own definition of rural identity in a place where their place in this society is continuously in question. Beyond entertainment, these stories were written with the intent to provoke thought into what it mean to live in a rural place, how people affect their environment, and what people do as they struggle to maintain and change their identity
The Role of Arkansas Rural Libraries in Cultural Capital Development
Get PDFThis study explores the role of rural public libraries in Arkansas in fostering cultural capital development among youth. By employing a mixed-methods approach combining quantitative analysis from the 2022 Arkansas Public Library Survey and qualitative insights gathered from semi-structured interviews with rural librarians, the research investigates three core questions: (1) How do rural libraries impact youth cultural capital development? (2) In what ways can these libraries enhance their effectiveness in this area? (3) How do librarians perceive their roles in this developmental process?
Findings indicate that rural libraries serve as pivotal cultural coordinators and community hubs, positively affecting youth engagement through targeted programs, diverse resources, and collaborative efforts. Although traditional library resources, including print materials, remain vital, the study highlights the importance of innovative programming tailored to community interests, including STEM activities and community partnerships. However, challenges such as limited funding, staffing, and perceptions of libraries hinder broader participation among young adults.
Recommendations emphasize the need for improved physical spaces, enhanced staffing—with a focus on hiring Master of Library Science graduates—and active community involvement to redefine librarians\u27 roles as cultural advocates capable of fostering long-term youth engagement. The findings suggest that with strategic investment and strengthened support from county governments, rural libraries could significantly improve their contribution to cultural capital development initiatives, thereby enhancing educational outcomes and economic prospects for the communities they serve