36 research outputs found
SDR-GAIN: A High Real-Time Occluded Pedestrian Pose Completion Method for Autonomous Driving
To mitigate the challenges arising from partial occlusion in human pose
keypoint based pedestrian detection methods , we present a novel pedestrian
pose keypoint completion method called the separation and dimensionality
reduction-based generative adversarial imputation networks (SDR-GAIN) .
Firstly, we utilize OpenPose to estimate pedestrian poses in images. Then, we
isolate the head and torso keypoints of pedestrians with incomplete keypoints
due to occlusion or other factors and perform dimensionality reduction to
enhance features and further unify feature distribution. Finally, we introduce
two generative models based on the generative adversarial networks (GAN)
framework, which incorporate Huber loss, residual structure, and L1
regularization to generate missing parts of the incomplete head and torso pose
keypoints of partially occluded pedestrians, resulting in pose completion. Our
experiments on MS COCO and JAAD datasets demonstrate that SDR-GAIN outperforms
basic GAIN framework, interpolation methods PCHIP and MAkima, machine learning
methods k-NN and MissForest in terms of pose completion task. In addition, the
runtime of SDR-GAIN is approximately 0.4ms, displaying high real-time
performance and significant application value in the field of autonomous
driving
Quantum state purification
Quantum state purification is a process in which decoherence is partially reversed by using multiple copies of the input states that have been subject to the same decoherence effect. This thesis focuses on purifying the decoherence caused by the depolarizing channel. In the first half of the thesis, the purification problem is formally introduced and one efficient purification procedure featuring the swap-test is presented and analyzed. The rest of the thesis formulates the optimal purification problem as an optimization problem and applies it to qubit and qutrit purification
Parallel Self-Testing of EPR Pairs Under Computational Assumptions
Self-testing is a fundamental feature of quantum mechanics that allows a classical verifier to force untrusted quantum devices to prepare certain states and perform certain measurements on them. The standard approach assumes at least two spatially separated devices. Recently, Metger and Vidick [Metger and Vidick, 2021] showed that a single EPR pair of a single quantum device can be self-tested under computational assumptions. In this work, we generalize their results to give the first parallel self-test of N EPR pairs and measurements on them in the single-device setting under the same computational assumptions. We show that our protocol can be passed with probability negligibly close to 1 by an honest quantum device using poly(N) resources. Moreover, we show that any quantum device that fails our protocol with probability at most ? must be poly(N,?)-close to being honest in the appropriate sense. In particular, our protocol can test any distribution over tensor products of computational or Hadamard basis measurements, making it suitable for applications such as device-independent quantum key distribution [Metger et al., 2021] under computational assumptions. Moreover, a simplified version of our protocol is the first that can efficiently certify an arbitrary number of qubits of a single cloud quantum computer using only classical communication
Quantum Probability Estimation for Randomness with Quantum Side Information
We develop a quantum version of the probability estimation framework
[arXiv:1709.06159] for randomness generation with quantum side information. We
show that most of the properties of probability estimation hold for quantum
probability estimation (QPE). This includes asymptotic optimality at constant
error and randomness expansion with logarithmic input entropy. QPE is
implemented by constructing model-dependent quantum estimation factors (QEFs),
which yield statistical confidence upper bounds on data-conditional normalized
R\'enyi powers. This leads to conditional min-entropy estimates for randomness
generation. The bounds are valid for relevant models of sequences of
experimental trials without requiring independent and identical or stationary
behavior. QEFs may be adapted to changing conditions during the sequence and
trials can be stopped any time, such as when the results so far are
satisfactory. QEFs can be constructed from entropy estimators to improve the
bounds for conditional min-entropy of classical-quantum states from the entropy
accumulation framework [Dupuis, Fawzi and Renner, arXiv:1607.01796]. QEFs are
applicable to a larger class of models, including models permitting measurement
devices with super-quantum but non-signaling behaviors and semi-device
dependent models. The improved bounds are relevant for finite data or error
bounds of the form , where is the number of random bits
produced. We give a general construction of entropy estimators based on maximum
probability estimators, which exist for many configurations. For the class of
Bell-test configurations we provide schemas for directly optimizing
QEFs to overcome the limitations of entropy-estimator-based constructions. We
obtain and apply QEFs for examples involving the Bell-test
configuration to demonstrate substantial improvements in finite-data
efficiency.Comment: v2: Clarified soundness discussion and other edits, see the
explanation after the references. v3: Clarified discussion of examples and
comparisons. Parts of this paper have been published as Physical Review
Research, 2, 013016, 2020,
https://journals.aps.org/prresearch/abstract/10.1103/PhysRevResearch.2.01301
Streaming quantum state purification
Quantum state purification is the task of recovering a nearly pure copy of an
unknown pure quantum state using multiple noisy copies of the state. This basic
task has applications to quantum communication over noisy channels and quantum
computation with imperfect devices, but has only been studied previously for
the case of qubits. We derive an efficient purification procedure based on the
swap test for qudits of any dimension, starting with any initial error
parameter. Treating the initial error parameter and the dimension as constants,
we show that our procedure has sample complexity asymptotically optimal in the
final error parameter. Our protocol has a simple recursive structure that can
be applied when the states are provided one at a time in a streaming fashion,
requiring only a small quantum memory to implement
Baicalin-aluminum alleviates necrotic enteritis in broiler chickens by inhibiting virulence factors expression of Clostridium perfringens
Clostridium perfringens type A is the main cause of necrotic enteritis (NE) in chickens. Since the use of antibiotics in feed is withdrawn, it is imperative to find out suitable alternatives to control NE. Baicalin-aluminum complex is synthesized from baicalin, a flavonoid isolated from Scutellaria baicalensis Georgi. The present study investigated the effects of baicalin-aluminum on the virulence-associated traits and virulence genes expression of C. perfringens CVCC2030, it also evaluated the in vivo therapeutic effect on NE. The results showed that baicalin-aluminum inhibited bacterial hemolytic activity, diminished biofilm formation, attenuated cytotoxicity to Caco-2 cells, downregulated the expression of genes encoding for clostridial toxins and extracellular enzymes such as alpha toxin (CPA), perfringolysin O (PFO), collagenase (ColA), and sialidases (NanI, NanJ). Additionally, baicalin-aluminum was found to negatively regulate the expression of genes involved in quorum sensing (QS) communication, including genes of Agr QS system (agrB, agrD) and genes of VirS/R two-component regulatory system (virS, virR). In vivo experiments, baicalin-aluminum lightened the intestinal lesions and histological damage, it inhibited pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) expression in the jejunal and ileal tissues. Besides, baicalin-aluminum alleviated the upregulation of C. perfringens and Escherichia coli and raised the relative abundance of Lactobacillus in the ileal digesta. This study suggests that baicalin-aluminum may be a potential candidate against C. perfringens infection by inhibiting the virulence-associated traits and virulence genes expression