226 research outputs found
Large-Batch, Neural Multi-Objective Bayesian Optimization
Bayesian optimization provides a powerful framework for global optimization
of black-box, expensive-to-evaluate functions. However, it has a limited
capacity in handling data-intensive problems, especially in multi-objective
settings, due to the poor scalability of default Gaussian Process surrogates.
We present a novel Bayesian optimization framework specifically tailored to
address these limitations. Our method leverages a Bayesian neural networks
approach for surrogate modeling. This enables efficient handling of large
batches of data, modeling complex problems, and generating the uncertainty of
the predictions. In addition, our method incorporates a scalable,
uncertainty-aware acquisition strategy based on the well-known, easy-to-deploy
NSGA-II. This fully parallelizable strategy promotes efficient exploration of
uncharted regions. Our framework allows for effective optimization in
data-intensive environments with a minimum number of iterations. We demonstrate
the superiority of our method by comparing it with state-of-the-art
multi-objective optimizations. We perform our evaluation on two real-world
problems - airfoil design and color printing - showcasing the applicability and
efficiency of our approach. Code is available at:
https://github.com/an-on-ym-ous/lbn\_mob
Reducing destructive effects of drought stress on cucumber through seed priming with silicic acid, pyridoxine, and ascorbic acid along with foliar spraying with silicic acid
Cucumber is considered as a drought-sensitive plant so that a decrease in the soil moisture causes decreased yield and quality of cucumber. This study investigates the effects of seed priming and foliar application with silicic acid on biochemical traits of cucumber (Cucumis sativus L.) under drought stress through a split-split plot experiment with three replications. The main plot was allocated to different levels of drought stress including moderate drought stress (80-85% Field Capacity (FC)), severe drought stress (60-65% FC), and without stress – control (90-95% FC). The sub-plot was allocated to seed priming treatments at three levels: control (hydro-priming), ascorbic acid 150 mgL-1, and pyridoxine 0.04%. The sub-sub plot was assigned to foliar spraying with silicic acid at three levels: 0, 100, and 200 mgL-1. The results obtained from the evaluation of all traits showed that under free-stress condition, the best seed priming treatment belonged to pyridoxine 0.04% alone or along with foliar spraying of silicic acid at 100 mgL-1. In moderate drought stress, the best seed priming treatment belonged to pyridoxine 0.04% and foliar spraying with silicic acid at 200 mgL-1, and under severe drought stress, the best seed priming treatment belonged to pyridoxine 0.04% or ascorbic acid at 150 mgL-1
TrustMol: Trustworthy Inverse Molecular Design via Alignment with Molecular Dynamics
Data-driven generation of molecules with desired properties, also known as
inverse molecular design (IMD), has attracted significant attention in recent
years. Despite the significant progress in the accuracy and diversity of
solutions, existing IMD methods lag behind in terms of trustworthiness. The
root issue is that the design process of these methods is increasingly more
implicit and indirect, and this process is also isolated from the native
forward process (NFP), the ground-truth function that models the molecular
dynamics. Following this insight, we propose TrustMol, an IMD method built to
be trustworthy. For this purpose, TrustMol relies on a set of technical
novelties including a new variational autoencoder network. Moreover, we propose
a latent-property pairs acquisition method to effectively navigate the
complexities of molecular latent optimization, a process that seems intuitive
yet challenging due to the high-frequency and discontinuous nature of molecule
space. TrustMol also integrates uncertainty-awareness into molecular latent
optimization. These lead to improvements in both explainability and reliability
of the IMD process. We validate the trustworthiness of TrustMol through a wide
range of experiments
Quantum-limited time-frequency estimation through mode-selective photon measurement
By projecting onto complex optical mode profiles, it is possible to estimate
arbitrarily small separations between objects with quantum-limited precision,
free of uncertainty arising from overlapping intensity profiles. Here we extend
these techniques to the time-frequency domain using mode-selective
sum-frequency generation with shaped ultrafast pulses. We experimentally
resolve temporal and spectral separations between incoherent mixtures of
single-photon level signals ten times smaller than their optical bandwidths
with a ten-fold improvement in precision over the intensity-only Cram\'er-Rao
bound.Comment: Six pages, three figures. Comments welcome
Realization of high-fidelity unitary operations on up to 64 frequency bins
The ability to apply user-chosen large-scale unitary operations with high
fidelity to a quantum state is key to realizing future photonic quantum
technologies. Here, we realize the implementation of programmable unitary
operations on up to 64 frequency-bin modes. To benchmark the performance of our
system, we probe different quantum walk unitary operations, in particular
Grover walks on four-dimensional hypercubes with similarities exceeding 95\%
and quantum walks with 400 steps on circles and finite lines with similarities
of 98\%. Our results open a new path towards implementing high-quality unitary
operations, which can form the basis for applications in complex tasks, such as
Gaussian boson sampling
An Optimized Photon Pair Source for Quantum Circuits
We implement an ultrafast pulsed type-II parametric down conversion source in
a periodically poled KTP waveguide at telecommunication wavelengths with almost
identical properties between signal and idler. As such, our source resembles
closely a pure, genuine single mode photon pair source with indistinguishable
modes. We measure the joint spectral intensity distribution and second order
correlation functions of the marginal beams and find with both methods very low
effective mode numbers corresponding to a Schmidt number below 1.16. We further
demonstrate the indistinguishability as well as the purity of signal and idler
photons by Hong-Ou-Mandel interferences between signal and idler and between
signal/idler and a coherent field, respectively. Without using narrowband
spectral filtering, we achieve a visibility for the interference between signal
and idler of 94.8% and determine a purity of more than 80% for the heralded
single photon states. Moreover, we measure raw heralding efficiencies of 20.5%
and 15.5% for the signal and idler beams corresponding to detector-loss
corrected values of 80% and 70%.Comment: 11 pages, 8 figure
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