Treasures @ UT Dallas
Not a member yet
7697 research outputs found
Sort by
Annual Student Haiku Competition Entries 2025
No full textEntries submitted to the Eugene McDermott Library Annual Haiku Contest. The Haikus were composed by students and reflect on the nature of the Eugene McDermott Library and its building.Entries submitted to the Eugene McDermott Library Annual Haiku Contest. The Haikus were composed by students and reflect on the nature of the Eugene McDermott Library and its building
Men of Bronze: a Struggle for Dignity and Equality Through Military Service, 1940-1975
No full textThis dissertation examines the United States military’s initial exclusion of African American
men from combat training and the practice of assigning duties by race. This research aims to
reveal the policies and practices African American men face regarding their targeted recruitment
and exclusion from combat training. Historically, America has considered her military institution
a space inaccessible to all those deemed as “other.” This research examines the initial exclusion
of African American men in the military and their struggle for the right to serve and fight as men
during the conflicts of World War II, Korea, and Vietnam. In addition, this dissertation will also
examine the military achievements of African Americans as they continue the struggle for
dignity, respect, and equality in American society
Bridging the Gap: a Mixed-methods Analysis of Support Programs and First-generation College Student Outcomes
No full textOver the past several decades, there has been an increase in access to higher
education for underrepresented minorities. However, due to inequities that occur during
K-12 education, many historically underrepresented students struggle with the rigor of a
college education. To mitigate this, federal programs such as TRIO offer outreach to
support students from disadvantaged backgrounds as they pursue a college degree.
Additionally, individual institutions create their own outreach programs to support first-
generation and other historically underrepresented college students. While these
programs have increased retention among first-generation college students, little is
known about the effect of these programs on time to degree completion. Using a mixed-
methods approach, I analyzed a dataset of student information and conducted
interviews with college students. I found that overall, program participation had a
positive effect on a student’s time to degree completion, and the cultural and social
capital acquired through program participation helped students remove or mitigate
barriers to academic success
Organization's Strategic Decision Making: Acquisition Completion and International Joint Venture Termination
No full textThis dissertation explores the multifaceted landscape of corporate strategy, particularly in mergers
and acquisitions (M&As) and strategic alliances within dynamic environments. In a world
increasingly shaped by geopolitical tensions, sociopolitical issues, and rapid technological
advancements, my dissertation objective is to deepen our understanding of the intricate challenges
and opportunities that firms encounter in a dynamic world.
In doing so, I have drawn upon a diverse array of theories from management, finance, social
psychology, communications, and media studies. I regard this theoretical pluralism as a significant
strength of my dissertation, enabling a comprehensive exploration of my areas of interest from
multiple perspectives and facilitating the development of more nuanced theoretical frameworks to
explain the phenomena I observe.
In the first and second chapters, the focus is on understanding how firms navigate and adapt to
dynamic environments. Whether driven by sociopolitical uncertainty or environmental crises,
these dynamic contexts present both risks and opportunities for firms engaged in international
collaborations. By examining how these external uncertainties impact the longevity and strategic
decision-making processes within international joint ventures, the underlying theme across both
chapters is the need for firms to dynamically adapt to external pressures.
The first chapter explores the impact of sociopolitical uncertainty on the termination of IJVs from
a real options perspective. Traditionally, real options literature has focused on macroeconomic
uncertainties; however, this research extends the scope to include sociopolitical contexts. The
findings reveal a negative correlation between sociopolitical uncertainty in host countries and IJV
terminations, highlighting the strategic value of flexibility that IJVs offer in such environments.
This chapter also contributes to the enrichment of real options theory by integrating institutional
considerations, including both formal institutions (regulatory burden) and informal institutions
(cultural uncertainty and performance orientation). By doing so, it sheds light on how these factors
influence the valuation of real options in IJVs.
The second chapter of my dissertation examines the impact of media coverage on the termination
of international joint ventures (IJVs) in countries experiencing natural disasters. From a
sensemaking perspective, we propose that global media acts as an informational intermediary,
influencing foreign partners' decision making. These partners, through their sensemaking
activities, perceive natural disasters in the host country as adverse events that evoke empathy
towards the affected nation. Consequently, foreign partners are less inclined to dissolve their IJVs
during such crises, as reported by the media. Furthermore, we identify several scope conditions—
national pride in the home country, economic advantages for the home country, and previous
collaborations between entities from the home and host countries—that alter the effect of media
coverage on natural disasters on IJV terminations.
The third chapter of my dissertation examines the influence of CEOs' communications on M&A
outcomes. In today's digital era, characterized by rapid technological advancements, CEOs
increasingly use social media platforms to reach diverse audiences. My research investigates the
contrasting effects of CEOs' communications through Twitter versus traditional press releases on
target companies' perceptions of acquirers. I discovered that CEO tweets typically offer a
personalized communication mode, allowing CEOs to express their viewpoints in real time and
humanize their firms, thereby fostering relationships with potential partners and enhancing
business outcomes. Positive sentiments in CEO tweets are often interpreted as intimacy and
sincerity, leading to more favorable M&A outcomes. Conversely, corporate press releases, seen as
a depersonalized communication form, tend to emphasize the acquirer's strengths, such as earnings
growth and product innovation. However, in situations with conflicting interests, positive
sentiment in press releases might be perceived as over-optimistic or boastful, potentially hindering
acquisition success. Moreover, both main effects are attenuated by acquirers’ corporate social
responsibility.
This dissertation offers a comprehensive exploration of the impact of sociopolitical, environmental,
and communicative factors on corporate strategy within the context of IJVs and M&As. By
integrating theoretical perspectives from multiple disciplines and employing diverse
methodological approaches, this research provides valuable insights into the strategic decision-
making processes of MNEs. The findings underscore the importance of flexibility, emotions, and
communication in navigating the complexities of today's business environment. This dissertation
contributes to a deeper understanding of the strategic decisions that drive corporate success in a
dynamic world
Next Generation Millimeter Wave Antenna-in-package (AiP) Techniques
No full textMillimeter-wave (mm-wave) antenna-in-package (AiP) technology present design, integration,
and testing challenges when the operating frequencies are beyond 90GHz. In the absence of an
integrated active device, testing in-package antennas is not a trivial process. This work focuses on
the design and characterization of a 140-220GHz slot bowtie (SBT), and E-shaped patch (ESP)
antenna integrated in a flip chip enhanced-quad flat no leads (FC-eQFN) package test vehicle,
soldered to a printed circuit board. The |S11| performance for the SBT and ESP antennas are
measured through a ground-signal-ground (GSG) probe to understand the full impedance
bandwidth of the antenna under test (AUT). However, the radiation pattern characterization of
GSG probed antennas at these frequencies is not practical and present several challenges and an
alternate solution is needed. To mitigate the challenges of antenna radiation pattern
characterization, an in-package transition is incorporated into the SBT and ESPs test vehicle
feeding the AUT through a custom waveguide probe on the backside of the PCB which will also
allow to measure the |S11| performance. Due to the transition’s limited bandwidth, the overall
impedance bandwidth performance of the in-package SBT and ESP are reduced from 54GHz and
42GHz, respectively to 18.4GHz and 23GHz, respectively. The |S11| measurements for both GSG
and backside fed SBTs, and ESPs are presented and compared to the simulated results. By using
the FC-eQFN in-package transitions the SBT and ESP antennas achieve peak realized gains of
8.6dBi and 5dBi, respectively. By de-embedding the losses caused by the in-package transition,
the SBT and ESP antennas achieve peak realized gains of 9dBi and 6dBi, respectively
Active Microcantilevers for Atomic Force Microscopy (AFM)
No full textRecent progress in micro-machining technology has enabled the fabrication of electromechanical structures with micro-scale features and remarkable precision. Microcantilevers are among
such structures. They play a critical role in applications such as Atomic Force Microscopy
(AFM), Scanning Tunneling Microscopy (STM), Scanning Lithography Systems, and probe-
based data storage systems, all being Scanning Probe Microscopy (SPM) based methods.
Apart from imaging its application for characterization, manipulation, and fabrication of micro
and nanoscale samples in the ambient environment makes AFM a truly versatile instrument.
Several modes have been developed for AFM imaging, with the most common being: (i) contact
mode, in which the tip and the sample are in contact throughout the scan; (ii) tapping mode, in
which the tip and the sample are in intermittent contact; and (iii) non-contact mode, in which
there is no contact between tip and sample. In each imaging mode, a micromachined cantilever
with an atomically sharp tip interacts with the sample, and the resulting tip-sample interaction
forces are regulated using a feedback control system.
Oscillating the microcantilever and deflection sensing are the major parts of an AFM setup. In
the conventional AFM setup, the bulky external actuators and sensors are not desirable in some
applications like parallel imaging. In this report, we discuss the AFM mechanism. The sensing
and actuation methods are explained, and our proposed on-chip actuation and sensing methods
are discussed. We talk about the design, microfabrication, characterization, and application
of the custom-built active AFM microcantilevers. Our designed active microcantilevers are
connected to analog readout circuits and integrated with off-the-shelf tools to enhance AFM
setup and to use their on-chip sensor/actuator instead of external sensors/actuators
Visualization of High Dimensional and Longitudinal Data
No full textDimension reduction is a powerful technique for embedding high-dimensional data in a low-
dimensional space. It has become increasingly important for visualizing and discovering
hidden structures within complex datasets. For instance, in the field of biological science,
dimension reduction is critical for analyzing spatial gene expression patterns in the human
brain and single-cell RNA sequencing data. One of the most popular techniques for dimension
reduction is t-distributed stochastic neighbor embedding (t-SNE), which is widely used for
visualizing and clustering high-dimensional data. However, t-SNE has limitations. While it
is excellent at preserving the distance between similar points, it can result in a loss of global
structure. Each time t-SNE is run, the clusters in the low-dimensional space are arranged
differently. Additionally, t-SNE struggles to maintain global similarities between clusters
in datasets with complex hierarchies. To perform accurate data analysis, it is essential to
maintain both local and global structures. We have developed a novel dimension reduction
technique that reveals both the local and global structure of high-dimensional data when
embedded in a two-dimensional plane. Our clustering-guided t-SNE technique combines t-
SNE with k-means clustering algorithm to preserve nearby and distant neighborhoods in the
dataset. We measure the performance of our proposed method using scalar quality metrics
that assess the preservation of both local and global structures.
In another project, we work on visualizing longitudinal imaging data using a machine learning
framework. Longitudinal data refers to data that is collected by measuring temporal variables
of interest over a specific time interval for an individual. Over the years, longitudinal data
has often been used in the medical field to monitor the advancement of cognitive disorders
like Alzheimer’s Disease, Parkinson’s disease, and Dementia. It is also used to evaluate the
effectiveness of treatments over an extended period of time. To accomplish our goal, we
develop a machine learning model that takes images from the same or different subjects
as input and projects the latent representation of a pair of images in a two-dimensional
plane. Through our algorithm, the projected images are represented by trajectory vectors,
where trajectory vectors from the same subject are grouped and aligned in the direction
corresponding to a single time-varying factor. To illustrate our algorithm’s effectiveness, we
apply it to both synthetic and real-life datasets
Low-cost GNSS-based Space Weather Monitors: Development Deployment, and Scientific Applications
No full textThis dissertation describes results of efforts related to the development, deployment and scientific
applications of a low-cost ionospheric scintillation and total electron content (TEC) monitor. These
efforts were motivated by the problem of the relatively high cost of specialized commercial
ionospheric scintillation and TEC monitors. They were also motivated by recent reports about the
occurrence of large ionospheric disturbances at middle latitudes, challenging the space science
community to monitor scintillation activity over this region. Prior to these reports, the occurrence
of significant ionospheric disturbances were thought to be limited to low and high latitudes.
Measurements of ionospheric scintillation and TEC allow advances in our understanding of the
space environment near-Earth (geospace). This includes the fundamental physical processes
driving ionospheric variability that are associated with solar and geomagnetic activity. The study
of scintillation and TEC is also motivated by challenges imposed on the performance of Global
Navigation Satellite Systems (GNSS). Chapter 1 of this dissertation provides a brief description
of ionospheric effects on radio signals and how these effects can be used for remote sensing the
Earth’s ionosphere. Chapter 2 describes and discusses the development of a novel GNSS-based
ionospheric scintillation and TEC monitors (ScintPi 2.0 and 3.0) that are not only low cost but also
easy to deploy and maintain. The description is accompanied by a discussion of measurements of
low latitude scintillation and TEC depletions associated with the so-called equatorial plasma
bubbles (EPBs). The ScintPi measurements are compared with collocated observations made by a
commercial monitor (Septentrio PolaRx5S). Chapter 3 extends the ScintPi’s application to
unprecedent observations of scintillation at low-to-mid latitudes during geomagnetically quiet
conditions, while Chapter 4 presents and discusses the application of ScintPi in the observation of
a low-to-mid latitude severe scintillation event triggered by a geomagnetic storm. Chapter 5
expands ScintPi measurements in studies of ionospheric irregularity drifts at low latitudes. Chapter
6 reveals, for the first time, the occurrence of extraordinary scintillation events simultaneously
detected by ScintPi monitors distributed across low to mid latitudes. Finally, Chapter 7 summarizes
the main results, highlights the dissertation contributions, and provides suggestions for future
work
Economic Sanctions: Bust or Boom?
No full textWhile recent research finds negative effects of sanctions on the income of target countries, there
is a call for more detailed examination of the effects and some insecurity whether sanctions can
lead to higher income in certain circumstances. National income identities would suggest a positive
effect for export restrictions. This paper analyses the effects of different UN, US and EU sanctions
on growth and business cycle, while simultaneously testing the theory of trade dependence
between sender and target country. To do so the GDP data for the large N dataset is filtered for
growth and business cycle, a dynamic panel analysis is employed additional to panel fixed effects
and interaction terms are implemented. The results are not consistent enough to confirm the theory
from the identities, however spark doubt on the current findings on a generalizable negative effect
on income. In contrast to that there is stronger evidence for the trade dependence hypothesis
Collaborative Interactive Mixed Reality Navigation System Measurement and Creation
No full textMixed Reality (MR) has been developed rapidly in recent years and is used to potentially
improve work efficiency and human living environments (such as life-related and entertainment
applications). Microsoft HoloLens has played an essential role in the progress of MR as a state-
of-the-art head-mounted device (HMD), from the first generation to the second generation.
In this work, we first systematically evaluate the features that utilized sensors, including
RGB cameras, eye cameras, depth cameras, microphone array, and Inertial Measurement Unit
(IMU) built in the HoloLens 2 to help readers gain basic knowledge about this MR device.
Then, we additionally conducted an experiment and enlisted over 50 participants to assess the
effectiveness of depth perception of color, luminance, and distance of virtual objects in the
MR environment. By utilizing the knowledge mentioned above, we construct a collaborative,
interactive, and dynamic MR environment in the HoloLens 2 using data gathered from the
surrounding physical environment to create a shared virtual space and semantically replicate
the physical environment to facilitate real-time object interaction and minimal scene update
delays. Collaboration is enabled through a Leader-Follower paradigm, allowing users to
individually navigate the virtual environment. Multiple users access synchronized scenes
with low latency updates, aligning with their physical movements; we called this system
a Collaborative Interactive Dynamic Environments for Mixed Reality (CIDER). Based on
CIDER, we demonstrate the use of MR information for navigation using a mini-map and by
also manipulating wall opacity to provide complete see-through and dynamic X-ray vision.
X-ray vision is a technique that allows users to see through walls and other obstacles. The
dynamic X-ray vision is generated in real-time based on the user’s current position and
updates as the user moves in the physical environment. Unlike previous works, our developed
system enables users to move freely and still maintain real-time X-ray vision, offering depth
perception and additional information about the surrounding environment. To assess the
X-ray vision system’s effectiveness, we first devised a target tagging game and enlisted
multiple participants to demonstrate how this system assists users in perceiving information
behind obstacles, serving as proof of concept. Then, we propose an improved formula with
normalization as a motion parallax evaluation standard with a verification experiment and
an X-ray vision-related experiment to show this system effectively affects motion parallax