All major web mapping services use the web Mercator projection. This is a poor choice for maps of the entire globe or areas of the size of continents or larger countries because the Mercator projection shows medium and higher latitudes with extreme areal distortion and provides an erroneous impression of...
Dynamic bipedal robots, which are capable of versatile behaviour, are rare. Most bipedal robots are either versatile and static or dynamic and limited to specific gaits. Over the last twenty years the bio-inspired spring mass model became a versatile template for bipedal walking and running gaits with many studies motivated...
This paper discusses issues of importance to designers of media for visually impaired users. The paper considers the influence of human factors on effectiveness of presentation as well as the strengths and weaknesses of tactile, vibrotactile, static pins, haptic, force feedback, and multimodal methods of rendering maps, graphs and models....
A new enhanced swing class-D VCO which operates from a supply voltage as low as 300 mV is presented. The architectural advantages are described along with an analysis for the oscillation frequency. Prototype differential and quadrature variants of the proposed VCO have been implemented in a 65 nm RF CMOS...
This paper presents the design of a continuous-time ΔΣ modulator (CTDSM) to be used in an ultrasound beamformer for biomedical imaging. To achieve better resolution, the prototype modulator operates at 1.2 GHz. It incorporates a digital excess loop delay (ELD) compensation to replace the active adder in front of the...
This paper presents recent advancements in resource management for large-scale DSA Systems. Although the problem of spectrum and power allocation is well addressed in the literature, the need for more efficient algorithms still persists due to the exponential growth of the number of wireless devices. Thus, developing efficient distributed approaches...
Energy consumption has become a significant concern for cloud service providers due to financial as well as environmental factors. As a result, cloud service providers are seeking innovative ways that allow them to reduce the amount of energy that their data centers consume. They are calling for the development of...
Software-Defined Networking (SDN) is a new networking
paradigm that decouples the forwarding and control planes—
traditionally being coupled with one another—while adopting a
logically centralized architecture aiming to increase network agility
and programability. While many efforts are currently being made
to standardize this emerging paradigm, careful attentions need to
be...
This paper presents novel data fusion methods
that enable teams of vehicles to perform target search tasks
without guaranteed communication. Techniques are introduced
for merging estimates of a target’s position from vehicles that
regain contact after long periods of time, and a fully distributed
team planning algorithm is proposed that...
Data attacks on state estimation modify part of system
measurements such that the tempered measurements cause
incorrect system state estimates. Attack techniques proposed
in the literature often require detailed knowledge of system
parameters. Such information is difficult to acquire in practice.
The subspace methods presented in this paper, on the...
Ocean wave energy has the potential to significantly
contribute to sustainable power generation in coastal regions.
Much of the research effort has gone into developing time domain
state space models of point absorber wave energy converters
(WECs) and subsequently into model-based optimal control to
efficiently harvest the maximum possible amount...
Most of the research on wave energy conversion
has been focused on the characterization of the
dynamic behavior of arrays of uncontrolled WECs in
specific configurations, in order to quantify changes
in the wave fields and absorbed power without active
control. To maximize wave energy conversion, however,
it is necessary...
Optimized processing conditions for
Pt/TiO₂/SiO₂/Si templating electrodes were investigated. These
electrodes are used to obtain [111] textured thin film lead
zirconate titanate (Pb[ZrₓTi₁₋ₓ]O₃ 0≤x≤1) (PZT). Titanium
deposited by dc magnetron sputtering yields [0001] texture on a
thermally oxidized Si wafer. It was found that by optimizing
deposition time, pressure, power,...
Non-line-of-sight (NLOS) propagation is one of the
major problems that cause errors in localization systems. There
exist many algorithms to reduce NLOS caused errors. Most of
these algorithms require a priori information about the NLOS
links, which limits their application. Least median of squares
(LMedS) method is an exception and...
Marine Protected Areas (MPAs) are regions in the ocean or along coastlines where fishing is controlled to avoid the reduction or elimination of fish populations. A central question is where exactly to establish an MPA. We cast this as an optimal problem along a one-dimensional coast-line, where fish are assumed...
It is demonstrated in this paper that it is possible
to synthesize a stochastic flash ADC entirely from Verilog code
and a standard digital library. An analog comparator is introduced
that is constructed from two cross-coupled 3-input digital
NAND gates, and can be described in Verilog. The synthesized
comparators have...
Assistive mobile manipulators have the potential
to one day serve as surrogates and helpers for people with
disabilities, giving them the freedom to perform tasks such as
scratching an itch, picking up a cup, or socializing with their
families. This article introduces a collaborative project with the
goal of putting...
Identifying coherent sub-graphs in networks is important
in many applications. In power systems, large systems
are divided into areas and zones to aid in planning and control
applications. But not every partitioning is equally good for
all applications; different applications have different goals, or
attributes, against which solutions should be...
Spatiotemporal planning involves making choices at multiple locations in space over some planning horizon to maximize utility and satisfy various constraints. In Forest Ecosystem Management, the problem is to choose actions for thousands of locations each year including harvesting, treating trees for fire or pests, or doing nothing. The utility...
A low-power forwarded-clock I/O transceiver architecture is presented that employs a high degree of output/input multiplexing, supply-voltage scaling with data rate, and low-voltage circuit techniques to enable low-power operation. The transmitter utilizes a 4:1 output multiplexing voltage-mode driver along with 4-phase clocking that is efficiently generated from a passive poly-phase...
Computer science courses typically incorporate integrated training in software engineering, which includes learning how to reuse existing code libraries in new programs. This commonly presents a need to use the libraries’ application programming interfaces (APIs) during project-based learning activities. The students learn these APIs with little support from the instructor....
Estimation accuracy and computational complexity
are two major areas of consideration for localization system
design. For time-of-arrival based systems, the 1st-order method
of moments (MOM) least-square (LS) estimator is simple to
implement, but its performance is much worse than that of
some computationally more complex estimators such as the
MOM...
Small solid-state photomultipliers (SSPMs) are an alternative scintillator light-detection technology to traditional photomultiplier tubes that offer advantages such as lower bias voltages and insensitivity to magnetic fields. A digital spectrometer using a commercially available SSPM was constructed and characterized at Oregon State University as a prototype for small, highly-mobile, low-power,...
Several efforts have recently been made to relate the displacement of swimming three-link systems over strokes to geometric quantities of the strokes. In doing so, they provide powerful, intuitive representations of the bounds on a system’s locomotion capabilities and the forms of its optimal strokes or gaits. While this approach...
This paper introduces a simple yet effective shape analysis mechanism for geometry processing. Unlike traditional shape
analysis techniques which compute descriptors per surface point up to certain neighborhoods, we introduce a shape analysis
framework in which the descriptors are based on pairs of surface points. Such a pairwise analysis approach...
In this paper, we propose an improved version of the min-sum algorithm for low density parity check (LDPC) code decoding, which we call “adaptive normalized BP-based” algorithm. Our decoder provides a compromise solution between the belief propagation and the min-sum algorithms by adding an exponent offset to each variable node’s...
Extended-counting A/D converters are proposed which achieve a high
accuracy by performing the conversion in several cycles. During the
first cycle, the circuit performs as an incremental ADC, while during the
remaining ones it acts as a multi-slope counting converter. With only
one opamp and a single-slope ADC, the accuracy...
A new incremental ADC is proposed which extends the order of a
conventional incremental ADC from N to (2N-1) by way of a two-step
operation. For a given conversion time, the duration of each step can be
optimized. For an Nth-order IADC, the performance is equivalent to that
of a...
In this letter, a simple and highly efficient successive-approximation
Registers (SAR) ADC realization is proposed. It requires an op-amp,
a comparator and only three equal-valued capacitors. The proposed
scheme is insensitive to the capacitor parasitics, and has a small
capacitance spread. With an oversampled scheme, it also allows
noise-shaping the...
An R2R DAC using 3 digital input levels rather than 2 has been
proposed as well as a modified 2-level structure that emulates the 3-level
DAC’s benefits. This 3-level structure provides and power reductions of
79% and linearity improvements due to matching of a factor of 2 over
the 2-level...
High heat fluxes and stringent constraints on surface temperature and its uniformity during thermal management
of electrical and electronic components often necessitate use of boiling heat transfer. This study compares the
pool and jet impingement boiling heat transfer characteristics of deionized water and FC‐72 at an equivalent fluid saturation temperature...
In this paper, we present the design, fabrication and characterization of a traveling
wave directional coupler modulator based on electro-optic polymer, which is able to provide
both high linearity and broad bandwidth. The high linearity is realized by introducing Δβ-reversal technique in the two-domain directional coupler. A travelling wave electrode...
Micro Aerial Vehicles (MAVs) are notoriously
difficult to control as they are light, susceptible to minor
fluctuations in the environment, and obey highly non-linear
dynamics. Indeed, traditional control methods, particularly
those relying on difficult to obtain models of the interaction
between an MAV and its environment have been unable
to...
This paper provides a cross-layer analysis of uplink performance in femtocell networks. It characterizes the uplink physical
interference in femtocell networks and studies its impact on the delay and data loss rate of constant-bit-rate (CBR) traffic, as well
as on the maximum achievable femto-user throughput. Our work derives data-link layer...
Design of time-varying vector fields, i.e., vector fields that can change over time, has a wide variety of important applications
in computer graphics. Existing vector field design techniques do not address time-varying vector fields. In this paper, we present a
framework for the design of time-varying vector fields, both for...
We present a novel and simple experimental method
called Physical Human Interactive Guidance to study human-planned
grasping. Instead of studying how the human uses his/her
own biological hand or how a human teleoperates a robot hand
in a grasping task, the method involves a human interacting
physically with a robot...
An analysis of the statistics of multi-stage (pipeline, SAR and algorithmic) ADCs with redundancy is performed and the ability to achieve an extra 6dB of resolution in ADCs with half-bit redundancy is shown due to probability density function (PDF) residue shaping. This paper classifies redundancy techniques to show that only...
This paper introduces a class of k-nearest neighbor (k-NN) estimators called bipartite plug-in (BPI) estimators for estimating integrals of non-linear functions of a probability density, such as Shannon entropy and R´enyi entropy. The density is assumed to be smooth, have bounded support, and be uniformly bounded from below on this...
A statistical analysis technique for estimating bit-error rate (BER) and eye
opening is presented for both NRZ and duobinary signaling schemes. This method
enables fast and accurate BER distribution simulation of a serial link transceiver
including channel and circuit imperfections, such as finite pulse rise/fall time, duty cycle
variation, and...
Current multi-gigahertz ADC performance is
limited by the sampling clock timing jitter. This paper describes
the effects of clock transition time on the spurious-free dynamic
range (SFDR) of a CMOS T/H circuit. A signal-dependent
nonlinearity model is first introduced that provides insight on the
effect of finite clock transition time,...
In this paper, we introduce a new approach to computing a Morse decomposition of a vector field on a triangulated manifold surface. The basic idea is to convert the input vector field to a piecewise constant (PC) vector field, whose trajectories can be computed using simple geometric rules. To overcome...
This paper describes a new analog-to-digital converter based on the traditional dual-slope ADC operation. With a small modification to the discharging phase of the dual-slope ADC, first-order quantization noise shaping is achieved. This quantizer is used in a second-order loop filter and results in an overall third-order quantization noise shaping....
Polyphase complex scrambling patterns are designed to extend the zero-correlation zone (ZCZ) of a family of user spreading sequences, called properly scrambled Walsh-Hadamard (PSW) codes, recently proposed for quasi-synchronous (QS) code-division multiple-access systems. The merits of the binary (ZCZ equals 2) and quadri-phase (ZCZ equals 4) PSW codes over the...
A reference-less highly digital half-rate clock and data recovery (CDR) circuit with improved tolerance to input duty cycle error is presented. Using a chain of frequency dividers, the proposed frequency detector produces a known sub-harmonic tone from the incoming random data. A digital frequency-locked loop uses the extracted tone, and...
High-speed, low-power design of Viterbi decoders for trellis coded modulation (TCM) systems is presented in this paper. It is well known that the Viterbi decoder (VD) is the dominant module determining the overall power consumption of TCM decoders. We propose a pre-computation architecture incorporated with T-algorithm for VD, which can...
This paper explores the development of biomechanical models for evaluating a new class of passive mechanical implants for orthopedic surgery. The proposed implants take the form of passive engineered mechanisms, and will be used to improve the functional attachment of muscles to tendons and bone by modifying the transmission of...
In this paper, we report a fiber-optic carbon dioxide (CO₂) near-infrared (IR) absorption sensor with only 8-cm sensing length that is coated with nanoporous metalorganic framework material Cu-BTC (BTC = benzene-1,3, 5-tricarboxylate). The multimode optical fiber was etched by hydrofluoric acid to remove the cladding and part of the core,...
This short note demonstrates that sparse recovery can be achieved by an l₁-minimization ersatz easily implemented using a conventional nonnegative least squares algorithm. A connection with orthogonal matching pursuit is also highlighted. The preliminary results call for more investigations on the potential of the method and on its relations to...
How do you test a program when only a single user, with no expertise in software testing, is able to determine if the
program is performing correctly? Such programs are common today in the form of machine-learned classifiers. We consider the
problem of testing this common kind of machine-generated program...
A wearable, multi-modal sensor is presented that can non-invasively monitor a patient’s activity level and heart function concurrently for more than a week. The 4in² sensor incorporates both a non-contact heartrate sensor and a 5-axis inertial measurement unit (IMU), allowing simultaneous heart, respiration, and movement monitoring without requiring physical contact...
Synchronous and colocated optical and microwave
signals from waves in the surf zone are presented and analyzed.
The field data were collected using a high-resolution video system
and a calibrated horizontally polarized marine radar during the
decaying phase of a storm. The resulting changes in the received
signals from varying...
In this paper, measurements of high-frequency
broadband (160–590 kHz) acoustic backscattering from surface
trapped nonlinear internal waves of depression are presented.
These waves are ideal for assessing the contribution from oceanic
microstructure to scattering as they are intensely turbulent.
Almost coincident direct microstructure measurements were performed
and zooplankton community structure...
The Internet enables global dissemination and
retrieval of information at any time, as a result, it has
a tremendous impact on how libraries provide
reference services to this new web-based clientele.
One impact is the increase in off-site library users
who make in-person reference interviews impossible.
To serve this new...