357 research outputs found
Agassiz, Garman, Albatross, and the Collection of Deep-sea Fishes
The first of Alexander Agassiz’ voyages on the U.S. Fish Commission steamer Albatross in 1891 yielded significant scientific results. This paper reviews the background of the voyage, including the career path that led Agassiz to the back deck of the Albatross. We also give a brief account of the life and work of Samuel Garman. Garman wrote up the ichthyological material from this Albatross voyage in a magnificent book on deep-sea fishes published in 1899. This book was exceptional in its coverage, anatomical detail, and recognition of phylogenetically important morphology
Functional programming languages for verification tools: a comparison of Standard ML and Haskell
Artificial Intelligence based Position Detection for Hydraulic Cylinders using Scattering Parameters
Position detection of hydraulic cylinder pistons is crucial for numerous
industrial automation applications. A typical traditional method is to excite
electromagnetic waves in the cylinder structure and analytically solve the
piston position based on the scattering parameters measured by a sensor. The
core of this approach is a physical model that mathematically describes the
relationship between the measured scattering parameters and the targeted piston
position. However, this physical model has shortcomings in accuracy and
adaptability, especially in extreme conditions. To overcome this problem, we
propose Artificial Intelligence (AI)-based methods to learn the relationship
directly data-driven. As a result, all Artificial Neural Network (ANN) models
in this paper consistently outperform the physical one by a large margin. Given
the success of AI-based models for our task, we further deliberate the choice
of models based on domain knowledge and provide in-depth analyses combining
model performance with the physical characteristics. Specifically, we use
Convolutional Neural Network (CNN)s to discover local interactions of input
among adjacent frequencies, apply Complex-Valued Neural Network (CVNN) to
exploit the complex-valued nature of electromagnetic scattering parameters, and
introduce a novel technique named Frequency Encoding to add weighted frequency
information to the model input. By combining these three techniques, our best
performing model, a complex-valued CNN with Frequency Encoding, manages to
significantly reduce the test error to hardly 1/12 of the one given by the
traditional physical model.Comment: 16 pages, 10 figure
A quantum logic gate for free electrons
The topological charge of vortex electrons spans an infinite-dimensional
Hilbert space. Selecting a two-dimensional subspace spanned by , a
beam electron in a transmission electron microscope (TEM) can be considered as
a quantum bit (qubit) freely propagating in the column. A combination of
electron optical quadrupole lenses can serve as a universal device to
manipulate such qubits at the experimenter's discretion. We set up a TEM probe
forming lens system as a quantum gate and demonstrate its action numerically
and experimentally. High-end TEMs with aberration correctors are a promising
platform for such experiments, opening the way to study quantum logic gates in
the electron microscope
A quantum logic gate for free electrons
The topological charge of vortex electrons spans an infinite-dimensional Hilbert space. Selecting a two-dimensional subspace spanned by , a beam electron in a transmission electron microscope (TEM) can be considered as a quantum bit (qubit) freely propagating in the column. A combination of electron optical quadrupole lenses can serve as a universal device to manipulate such qubits at the experimenter\u27s discretion. We set up a TEM probe forming lens system as a quantum gate and demonstrate its action numerically and experimentally. High-end TEMs with aberration correctors are a promising platform for such experiments, opening the way to study quantum logic gates in the electron microscope
A quantum logic gate for free electrons
The topological charge of vortex electrons spans an infinite-dimensional Hilbert space. Selecting a two-dimensional subspace spanned by , a beam electron in a transmission electron microscope (TEM) can be considered as a quantum bit (qubit) freely propagating in the column. A combination of electron optical quadrupole lenses can serve as a universal device to manipulate such qubits at the experimenter\u27s discretion. We set up a TEM probe forming lens system as a quantum gate and demonstrate its action numerically and experimentally. High-end TEMs with aberration correctors are a promising platform for such experiments, opening the way to study quantum logic gates in the electron microscope
Pattern representation and recognition with accelerated analog neuromorphic systems
Despite being originally inspired by the central nervous system, artificial
neural networks have diverged from their biological archetypes as they have
been remodeled to fit particular tasks. In this paper, we review several
possibilites to reverse map these architectures to biologically more realistic
spiking networks with the aim of emulating them on fast, low-power neuromorphic
hardware. Since many of these devices employ analog components, which cannot be
perfectly controlled, finding ways to compensate for the resulting effects
represents a key challenge. Here, we discuss three different strategies to
address this problem: the addition of auxiliary network components for
stabilizing activity, the utilization of inherently robust architectures and a
training method for hardware-emulated networks that functions without perfect
knowledge of the system's dynamics and parameters. For all three scenarios, we
corroborate our theoretical considerations with experimental results on
accelerated analog neuromorphic platforms.Comment: accepted at ISCAS 201
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