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Moving Toward Language Acquisition: Adapting and Applying Laban Movement Analysis in the English as an Additional Language Classroom
No full textThis dissertation investigates how Laban Movement Analysis (LMA), a system developed by
twentieth-century dance theorist, Rudolf Laban, can be adapted and applied toward the goal of
language acquisition in an international high school English as an Additional Language (EAL)
classroom. More specifically, I argue that the study of LMA categories (body, effort, space, and
shape) can be adapted as a method for use at a Swiss boarding school with the goal of improving
spoken and nonverbal communication, reading comprehension, and writing. My experience as
both a dance and writing educator informs my research. LMA is not to be confused with the
more complicated and esoteric system of dance documentation called Labanotation. Rather,
LMA is taught to movement specialists at the beginning of their careers across many fields
whereas Labanotation requires years of training to successfully read and write. LMA consists of
simple vocabulary and shapes that are much more relevant to students of EAL than is
Labanotation, which would likely be considered inaccessible or unintelligible to high school
students.
Additional goals of the case study include mapping patterns across language groups and
promoting cultural awareness, encouraging empathy, and reducing insensitive language by
drawing attention to movement. Given the lack of prior research connecting LMA and English
language learning, a pedagogical experiment in this area is warranted. Participants in this case
study include 43 high school students (ages 16-19 years) enrolled in three advanced-level EAL
courses at The American School in Switzerland, a private, co-educational international boarding
school. I gather data in the form of online questionnaires, written class work, and videotaped
performances with the permission of participants via Institutional Review Board approval,
serving as the students’ main English instructor. Possibilities for future research, exploration, and
development on a larger scale are also considered at the study’s conclusion. Ultimately, this
dissertation serves as a precedent and point of departure for broader, more far-reaching studies in
language learning and acquisition
Microelectrode Arrays for Chronic Neural Recording
No full textNeural interfaces are advanced devices that enable communication between neurons in the brain
or peripheral nervous system and external systems like computers or prosthetic devices. These
devices can be used to treat a variety of diseases, such as epilepsy or Parkinson’s, and restore lost
motor function through stimulation or the use of prosthetics. Two primary issues with currently
used neural interfaces for chronic implantation are the degradation of the insulation and
conductive materials and the response of the body to the devices, which is called the foreign
body response (FBR). To provide a possible avenue for the improved chronic functionality of
neural interface devices, the work in this dissertation explored the use of amorphous silicon
carbide (a-SiC) as a platform for device fabrication using thin film fabrication techniques. To
examine chronic functionality, 8 μm thick and 20 μm wide a-SiC devices with sputtered iridium
oxide film (SIROF) electrode coatings were implanted into rat motor cortex for a period of 16
weeks. Devices were characterized using electrochemical assessment and single-unit action
potential recordings. Electrochemical measurements revealed that the devices were chemically
and electrically stable over 16 weeks in cortex. Single-unit action potentials were recorded on
approximately 90% of channels 1 week after implantation, 75% of channels 13 weeks after
implantation, and 50% of channels 16 weeks after implantation. Immunohistochemistry
performed after the study revealed a depth dependent foreign body response to the devices.
Regions closer to the pial surface were found to have more FBR than deeper regions, where
deeper regions were at times indistinguishable from contralateral sham slices. Neuronal cell
bodies were shown to be close to the devices at all depths of interest. Sputtered ruthenium oxide
(RuOx) electrode coating films were also explored in vivo in a 6-week study in rat motor cortex.
RuOx films were deposited in place of SIROF on a-SiC devices. Again, devices were measured
using electrochemistry and neural recordings. RuOx devices displayed electrochemical stability
over 6 weeks. These devices were able to record single unit action potentials on approximately
75% of channels at week 1 and remained at 75% of channels at week 6. This dissertation also
explored the viability of using tantalum (Ta) metal deposited by DC magnetron sputtering as a
possible interconnect layer in neural interface devices. Properties of Ta were measured both with
and without a priming layer of Ti on a-SiC. It was found that it is possible to preferentially
differentiate Ta crystallographic phases based on the priming layer leading to the preferential
formation of a high electrical conductivity Ta film. Lastly, this dissertation explored the
electrochemical and morphological properties of titanium nitride (TiN) films as a function of
film thickness. Thin TiN films had charge injection capabilities similar to noble metals such as
platinum. It was also observed that TiN benefits from anodic biasing for use in stimulation,
further increasing charge injection capacity
Atomic Layer Deposition Application in Interconnect Technology: From Material Understanding to Area Selective Deposition
No full textAtomic layer deposition (ALD) technique has been widely employed in the semiconductor
industry. As the devices continuously scaling down to sub 3 nm, SiOx and SiNx thin films, for
applications such as a spacer or an etch stopper, are expected to satisfy stringent requirements (e.g.,
precise thickness control, high bulk film density, high wet-etch resistance, conformality, and lowthermal budget) in the current back-end-of-line process. Besides the film qualities, challenges in
the current “top-down” approach also need to be addressed to reduce the size of the devices.
Moreover, the lack of a fundamental understanding of surface chemistry using in-situ
characterization can further impede future interconnect technology.
This dissertation focuses on the application of the ALD process for current and future interconnect
technology applications. The first study is ALD of high-quality SiOx and SiNx films with lowtemperature feasibility. With the structural modification of conventional Si precursors (e.g., the
addition of ligand or substitution of terminating groups), the molecular polarity of precursors is
changed, resulting in the improvement of surface reactivities. By leveraging the unique structure
of the Si sources, the film deposition at low temperature with enhanced film properties can be
achieved. Secondly, this dissertation further identifies the correlation between the metal surface
condition and physical/chemical stability of passivation materials in application to the areaselective deposition process. Using in-situ reflectance absorption infrared spectroscopy (RAIRS),
X-ray photoelectron spectroscopy (XPS), and high-resolution TEM analysis, the issues arising
with poor ALD selectivity are identified. After analyzing the issues, the potential solution to
provide a high-quality SAM monolayer is demonstrated. Lastly, a cleaning process using a noble
metal cleaning agent, in which a clean metal surface at low temperature (< 200 o
C) can be achieved,
is developed. The unique cleaning process could pave the way for the implementation of the
consecutive organic-free area-selective-deposition process
Holistic Efficiency and Determinism for Autonomous Embedded Systems
No full textAutonomous Embedded Systems (AES), where software and embedded hardware components work in tandem to autonomously sense and/or manipulate the physical world, have
become increasingly more sophisticated in the past decade, culminating in the emergence of
complex systems such as autonomous vehicles. Often, the complex design makes it difficult to
effectively test and verify these systems, potentially causing unpredictable and unintended
behavior. In addition, AES have design constraints such as Space, Weight, and Power
(SWaP) limitations, and generally need to conform to many safety requirements and regulations. Often, these constraints and requirements contradict each other. For example, more
accurate control methods could result in safer operation, yet, increase energy consumption.
These contradictions could result in a suboptimal design.
This dissertation attempts to take a constructive step towards more testable, energy-efficient,
accurate, and timing-predictable AES. It is recognized that AES are constructed from multiple layers of software and hardware components. Adhering to the overall design goals of
the system requires solving unique challenges and trade-offs for each layer.
At the application layer, it is recognized that the emergence of Deep Neural Networks (DNNs)
imposes the biggest challenge for modern AES. DNNs in AES must be energy-efficient, accurate, and timing-predictable (where temporal constraints are honored), three goals that
often contradict each other. We take an incremental approach to solving this multidimensional optimization problem. First, PredJoule is presented, a framework that is capable of
meeting energy consumption goals at runtime while meeting temporal constraints for DNN
tasks. Second, ApNet is presented that allows for the system to dynamically adjust DNN
accuracy to honor temporal constraints. Finally, NeuOS is presented. NeuOS is a framework that is built upon the insights and techniques of PredJoule and ApNet, but allows
the system to optimize energy consumption and accuracy at the same time, while ensuring
timing-predictability at runtime for multiple DNN tasks.
At the hardware level, it is recognized that memory is a limited and contentious resource that
is often shared across multiple processors and accelerators on a single System-on-Chip (SoC).
Limitations in memory (both in terms of space and bandwidth) can make the system unstable
and cause critical tasks to take longer to execute or fail, even with modern techniques such
as on-demand memory swapping. To offer a more predictable alternative for AES, ResCue
is presented. ResCue can take over the memory management task in AES, bringing data in
and out of memory in a manner that guarantees timing-predictability.
Finally, the focus is turned to the middleware, a layer that sits in-between the application and
the hardware layers. Using a modern and complex open-source autonomous driving software,
Autoware.Auto, as a case study, it will be empirically shown that the middleware can cause
subtle, but critical unpredictable behavior that is normally hard to detect. Moreover, it
will be shown that the middleware used in Autoware.Auto lacks the ability to offer strong
consistency, leading to an untestable system. To offer a concrete remedy, Xronos is proposed,
based on Lingua Franca. Xronos is a framework with a semantic notion of time and built-in
coordination mechanisms that preserve strong consistency as well as temporal semantics in
modern distributed AES
Deformation Analysis of TPU Structures and Actuation Using SMA Coils for a Prosthetic Finger
No full textThis thesis focuses on experimental study on the use of coiled shape memory alloy (SMA) and
Peltier plates for robotic finger actuation, their manufacturing and design, and the relationships
between input magnitudes and output results such as finger joint angles. A fundamental flexible
structure based on cantilever beam that is 3D-printed using thermoplastic polyurethane (TPU) is
studied both experimentally and via simulations. The experiments for robotic finger actuation with
the use of coiled shape memory alloys and Peltier plates were all based on prior studies. However,
here extensive open loop characterization study has been conducted to understand the system.
First, we will go into the data that was acquired through characterization experiments for some
pre-made cantilever beams. This will help give us a better understanding on the movement and
characteristics of the robotic finger that is discussed in this work. Specifically, the bending
properties of a robotic finger that is actuated by coiled SMA and its characteristics in response to
change in amplitude of current and heating time.
Next, TPU cantilever beams were simulated using CAD analysis software package, such as
SolidWorks, to determine deflection in response to tip load. Structural analysis and frequency
analyses were performed. The simulation results were compared with experimental results and
good agreement in terms of the trend of the angles as the loads were varied. Instead of a solid
geometry, we used a serrated structure that resembles the 3D printed structure. This modification
was made because the advanced 3D printed used for the fabricated structures resulted in irregular
surface finish of the structure. Finally, discussion on results and future improvements will be
explained
Essays on Entrepreneurship: Initial Public Offerings and Venture Capital Financing
No full textThis dissertation investigates initial public offerings (IPOs) and venture capital financing, two
widely studied topics in the entrepreneurship domain. In each of the three chapters, I delve into
each topic by exploring a relatively unique aspect of a phenomenon. In Chapter 1, I explore the
case when investing in a distant industry, an agent in a network consisting of directional ties may
suffer a decline in performance due to its lack of industry-specific knowledge. Empirically
testing a population of venture capital (VC) firms spanning the entirety of Chinese VC history
from 1991 to 2017, supplemented by qualitative interviews with VC partners, Chapter 1 finds
that not every contact in such a network is able to advise the agent (the focal lead VC) equally
well, because contacts connected by different tie types possess different industry-specific
knowledge and tie directionality affects the likelihood of having contacts that possess needed
knowledge. Specifically, the focal lead VC benefits more from contacts connected by outward
ties than inward ties, while contacts connected by reciprocal ties provide the most informational
benefits
Performance Analysis and Scope of Residue Number System in Digital Computing and Hardware Security
No full textThe Residue Number System (RNS) has become increasingly popular in digital signal
processing and cryptography due to its innate parallelism and inherent non-linearity. RNS
represents numbers as remainders when divided by chosen moduli and enables parallel
processing, leading to efficient arithmetic operations. However, it requires computationally
expensive conversions and careful selection of the moduli set to avoid precision loss and
deal with overflow issues. In the field of hardware security, RNS is an attractive proposition
because of its highly non-linear transfer function that makes it difficult for attackers to model
or predict the behavior of the system. In this thesis, the scope of RNS in both efficient
computing and hardware security has been analyzed thoroughly. The application of RNS in
building a fast throughput Multiply and Accumulate (MAC) block through parallel processing
has been demonstrated in a 65 nm CMOS process, where post-layout performance evaluations
of the proposed RNS MAC demonstrate a 17% improvement in latency with an area-power
consumption overhead of 12% when compared to the traditional binary MAC. Moreover,
the promising aspect of the highly non-linear RNS in building a secure PUF has also been
examined rigorously by carrying out ML attacks against different behavioral PUF circuit
configurations
Polymeric Encapsulation of Vaccines for Enhanced Immunogenicity
No full textVaccines have been used for hundreds of years to provide protection against infectious diseases.
Early vaccine formulations provided strong protection as they were highly immunogenic but were
hindered by harsh associated side effects. In an attempt to improve the safety profiles of vaccines,
isolated components of pathogens were used instead of live-attenuated or whole-cell formulations.
These subunit vaccines were much more tolerable but were unfortunately less effective at
providing protection. To overcome this, several methods to adjuvant vaccines have been
investigated. One method is to improve cellular uptake of subunit antigens by the components of
the innate immune system, specifically antigen presenting cells (APCs) whereas another is to
prolong exposure of the antigen to the immune system via an antigen depot. Both of these
mechanisms have been effective in inducing long-lasting immunity via activation of T-cells and
B-cells. Herein a class of polymeric scaffolds, metal-organic frameworks (MOFs), have been
employed to improve both APC uptake of model vaccines and provide an antigen depot. This has
been shown to improve the immunogenicity of immunoadjuvants, subunit antigens, and wholecell vaccines
A Novel Immune-interactive Surface Coating Approach to Induce Implant Osseointegration in Diabetic Conditions
No full textTitanium (Ti) orthopedic devices are often used to restore the function of damaged bones.
However, reciprocal effects between implant surfaces and tissues can affect the success and
performance of the implant due to corrosion, micro motion, dislocation, infection, or the
inflammatory response of surrounding tissues. Additionally, diabetic patients receiving implants
exhibit higher rates of implant failure due to impaired osseointegration and systemic
complications compared to non-diabetic patients, which contribute to poor outcomes in
orthopedic treatments, such as fracture healing. Because there is an increasing diabetic
population that will require the use of implants, there is an urgent need to determine underlying
mechanisms of diabetes-induced poor osseointegration and bone repair.
Retrieved implants and in vitro testing of discs in simulated diabetic environments were first
analyzed to understand how diabetes affects Ti implant surfaces. All retrieved implants have
some degree of surface damage (pitting attack, discoloration, scratches, delamination, etc.).
Therefore, the goal of this dissertation was to develop a coating that mitigates failure modes and
improves the predictability of implants in immunocompromised conditions.
Two multifunctional dicationic imidazolium-based ionic liquids (IonLs) containing
phenylalanine (1,10-bis(3-methylimidazolium-1-yl)decane diphenylalanine) and methionine
(1,10-bis(3-methylimidazolium-1-yl)decane dimethionine) were first investigated as thin films to
prevent direct adsorption and temporarily immobilize exogenous proteins on Ti surfaces. The
selected protein for this study was High Mobility Group Box 1 (HMGB1), which has been
shown to be involved in the recruitment of inflammatory and mesenchymal stem cells to
implantation sites, contributing to healing and implant integration. The optimal IonL coating was
chosen based on in vitro and in silico analysis. It was demonstrated that HMGB1 is stable when
anchored by the IonL containing phenylalanine, which prevents protein denaturation from
surface adherence. However, HMGB1 is redox sensitive and exists in different isoforms (fully-
reduced HMGB1 (FR), a recombinant version of FR resistant to oxidation (3S), disulfide
HMGB1 (DS) and inactive sulfonyl HMGB1(SO)), that can each have distinct biological
functions in health and disease. Each isoform was applied to the IonL-Phe thin film and
implanted subcutaneously to assess the inflammatory effects of surrounding tissues in response
to the coating. From these studies, the 3S HMGB1 was selected as the most favorable with
regard to tissue healing, to be further applied to orthopedic implants in a model of open reduction
fracture fixation (ORIF) in tibias of diabetic rats. This coating conformation (Ti-IonL-HMBG1)
was then used in the ORIF model to assess the fracture healing and osseointegration potential in
diabetic and normoglycemic conditions. Overall, the results for the new coating pointed to
beneficial outcomes in fracture healing of diabetic rats, achieving healing parameters comparable
to non-diabetic rats. Altogether, this dissertation demonstrates the design and assessment of ionic
liquid and exogenous HMGB1 as an immunomodulatory coating to improve osseous healing in
diabetic conditions
200-400 GHz Antennas in Integrated Circuits Incorporating Packaging Effects
No full textThere is an increasing demand for wider bandwidth in high data rate applications. Using
frequency bands in the sub-millimeter wave and terahertz (THz) range allows for a significant
improvement of fractional bandwidth. The rise in operational frequency translates to reduced
wavelengths, which are comparable to the dimensions of the integrated circuits (ICs). This has
made the integration of antennas on a chip or within a semiconductor package possible.
Presented in this dissertation is a “simple” bond-wire antenna intended for operation at 180-GHz.
At 178.3 GHz, a gold bond wire shaped in a half loop and terminated on a bond pad of a
neighboring chip exhibits a measured peak gain of 2.5 dB at the = 90° plane. The antenna also
exhibits > 20-GHz measured −10-dB |S11| bandwidth. These measured results compare
favorably with the simulated results. This is the first bond-wire antenna (operating at 180-GHz)
that can be used for wireless communication in the broadside direction (perpendicular to the IC).
A 300-GHz on-chip patch antenna is also presented and the effects of semiconductor packaging
on the antenna performance are explored. Full-wave simulations of the rectangular patch
antenna, compliant with the metal stack and design rules of a 65-nm complementary metal–
oxide–semiconductor (CMOS) process, are implemented. The simulated results show an increase
of 13% in radiation efficiency, an increase of 1 dB in peak antenna gain, and a 7-GHz −10-dB
|S11| bandwidth improvement, upon encapsulation within a quad-flat no-lead (QFN) package
compared to one without encapsulation. Measured results (within a QFN package) of a 276-GHz
CMOS signal generator with the same on-chip antenna, show ∼6 dB higher effective isotropic
radiated power over that of an unpackaged chip, corroborating the simulation results. A
technique to improve the efficiency, gain and impedance bandwidth of on-chip planar patch
antennas, using the encapsulation material, is thus presented and design guidelines are suggested
for future planar on-chip antenna implementation.
An E-shaped patch geometry is simulated to demonstrate the improvement of impedance
bandwidth and gain over a rectangular patch. The −10-dB |S11| bandwidth of 3 GHz for
rectangular patch at 300 GHz, is improved four-fold to 12 GHz with this geometry. The peak
gain also improves by ~1 dB. To further improve the gain of a rectangular patch antenna, a 420-
GHz, eight-element on-chip series-fed patch antenna array is developed. This is the first array in
this configuration to be implemented on chip. The measured gain at boresight matches the
simulated gain of ~9 dB at 415.5 GHz. The overlapping measured and simulated radiation
patterns of this antenna demonstrates the reliability of antenna designs using EM simulations at
sub-millimeter wave and THz frequencies.
Power input to on-chip antennas at 200-400 GHz cannot be accurately measured in the presence
of probes. Preliminary simulation results presented show that root mean square voltage detectors
along with a phase detector can be used to determine the antenna input impedance in-situ,
thereby eliminating the use of probes for antenna measurements. The feasibility of this technique
for determination of the antenna characteristics is documented