413 research outputs found
Building recognition on subregionās multi-scale gist feature extraction and corresponding columns information based dimensionality reduction
Peer reviewedPublisher PD
Distinct responses of planktonic foraminiferal B/Ca to dissolution on seafloor
We have measured B/Ca in four core-top planktonic foraminiferal species (Globigerinoides ruber (white), Globigerinoides sacculifer (without final sac-like chamber), Neogloboquadrina dutertrei, and Pulleniatina obliquiloculata) from three depth transects (the Caribbean Sea, the southwestern Indian Ocean, and the Ontong Java Plateau) to evaluate the effect of dissolution on planktonic foraminiferal B/Ca. At each transect, G. ruber (w) and G. sacculifer (w/o sac) show decreasing B/Ca with increasing water depth. This decrease in B/Ca is accompanied with decreases in shell weights, Mg/Ca, and bottom water calcite saturation state. This indicates a postdepositional dissolution effect on B/Ca in these two species. The strong correlation observed between changes in B/Ca and bottom water calcite saturation state offers an approach to correcting for the dissolution bias. By contrast, B/Ca in N. dutertrei and P. obliquiloculata remains unchanged along depth transects, although shell weights and Mg/Ca display significant declines. Overall, our core-top results suggest species-specific dissolution effects on B/Ca in different planktonic foraminiferal species
Autonomy 2.0: The Quest for Economies of Scale
With the advancement of robotics and AI technologies in the past decade, we
have now entered the age of autonomous machines. In this new age of information
technology, autonomous machines, such as service robots, autonomous drones,
delivery robots, and autonomous vehicles, rather than humans, will provide
services. In this article, through examining the technical challenges and
economic impact of the digital economy, we argue that scalability is both
highly necessary from a technical perspective and significantly advantageous
from an economic perspective, thus is the key for the autonomy industry to
achieve its full potential. Nonetheless, the current development paradigm,
dubbed Autonomy 1.0, scales with the number of engineers, instead of with the
amount of data or compute resources, hence preventing the autonomy industry to
fully benefit from the economies of scale, especially the exponentially
cheapening compute cost and the explosion of available data. We further analyze
the key scalability blockers and explain how a new development paradigm, dubbed
Autonomy 2.0, can address these problems to greatly boost the autonomy
industry
Simulating the Kibble-Zurek mechanism of the Ising model with a superconducting qubit system
The Kibble-Zurek mechanism (KZM) predicts the density of topological defects
produced in the dynamical processes of phase transitions in systems ranging
from cosmology to condensed matter and quantum materials. The similarity
between KZM and the Landau-Zener transition (LZT), which is a standard tool to
describe the dynamics of some non-equilibrium physics in contemporary physics,
is being extensively exploited. Here we demonstrate the equivalence between KZM
in the Ising model and LZT in a superconducting qubit system. We develop a
time-resolved approach to study quantum dynamics of LZT with nano-second
resolution. By using this technique, we simulate the key features of KZM in the
Ising model with LZT, e.g., the boundary between the adiabatic and impulse
regions, the freeze-out phenomenon in the impulse region, especially, the
scaling law of the excited state population as the square root of the quenching
rate. Our results supply the experimental evidence of the close connection
between KZM and LZT, two textbook paradigms to study the dynamics of the
non-equilibrium phenomena.Comment: Title changed, authors added, and some experimental data update
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