631 research outputs found
Intention-Aware Planner for Robust and Safe Aerial Tracking
The intention of the target can help us to estimate its future motion state
more accurately. This paper proposes an intention-aware planner to enhance
safety and robustness in aerial tracking applications. Firstly, we utilize the
Mediapipe framework to estimate target's pose. A risk assessment function and a
state observation function are designed to predict the target intention.
Afterwards, an intention-driven hybrid A* method is proposed for target motion
prediction, ensuring that the target's future positions align with its
intention. Finally, an intention-aware optimization approach, in conjunction
with particular penalty formulations, is designed to generate a
spatial-temporal optimal trajectory. Benchmark comparisons validate the
superior performance of our proposed methodology across diverse scenarios. This
is attributed to the integration of the target intention into the planner
through coupled formulations.Comment: 7 pages, 10 figures, submitted to 2024 IEEE International Conference
on Robotics and Automation (ICRA
(3R,6R,12R,20S,24R)-20,24-Epoxydammarane-3,6,12,25-tetraol
In the title compound, C30H52O5, the three six-membered rings are in chair conformations, the five-membered ring is in an envelope form and the tetrahydrofuran ring has a conformation intermediate between half-chair and sofa. Intramolecular O—H⋯O hydrogen bonds may influence the conformation of the molecule. In the crystal, molecules are linked by intermolecular O—H⋯O hydrogen bonds, forming a three-dimensional network
Efficient market hypothesis and fraud on the market theory: A new perspective for class actions
Following recent judgement of the Supreme Court of US (June 2014), several commentators had declared that “Securities class actions are here to stay” (insidecounsel.com – September 2014, 11). This paper provides a critical perspective on this judgement, which “implicates substantive issues at the intersection of economic theory, financial markets, and securities regulation” (128 Harv. L. Rev. 291 2014-2015, 291), and shows that we must be much more careful. This recent judgement is based on the Fraud on the Market Doctrine, which was introduced in 1973 in order to preserve the class action procedure in securities fraud litigation. The characteristic of the Fraud on the Market Doctrine is to have been structured from one of the most popular financial theory: Efficient Market Hypothesis. In this paper, by analysing the implementation of the Efficient Market Hypothesis in Fraud on the Market Theory, we argue that if the Supreme Court had to take position for a second time about the Fraud on the Market Doctrine it is due to the practical difficulties inherited from Efficient Market Hypothesis and that have raised several problems to the US courts, including the Supreme Court. This issue is illustrated by the definition of Efficient Market Hypothesis lawyers used (“most” vs “all”/”fully”). As this paper shows, if “Securities class actions are here to stay”, the opportunity to open such a class action is strongly reduced in the facts
Are AlphaZero-like Agents Robust to Adversarial Perturbations?
The success of AlphaZero (AZ) has demonstrated that neural-network-based Go
AIs can surpass human performance by a large margin. Given that the state space
of Go is extremely large and a human player can play the game from any legal
state, we ask whether adversarial states exist for Go AIs that may lead them to
play surprisingly wrong actions. In this paper, we first extend the concept of
adversarial examples to the game of Go: we generate perturbed states that are
``semantically'' equivalent to the original state by adding meaningless moves
to the game, and an adversarial state is a perturbed state leading to an
undoubtedly inferior action that is obvious even for Go beginners. However,
searching the adversarial state is challenging due to the large, discrete, and
non-differentiable search space. To tackle this challenge, we develop the first
adversarial attack on Go AIs that can efficiently search for adversarial states
by strategically reducing the search space. This method can also be extended to
other board games such as NoGo. Experimentally, we show that the actions taken
by both Policy-Value neural network (PV-NN) and Monte Carlo tree search (MCTS)
can be misled by adding one or two meaningless stones; for example, on 58\% of
the AlphaGo Zero self-play games, our method can make the widely used KataGo
agent with 50 simulations of MCTS plays a losing action by adding two
meaningless stones. We additionally evaluated the adversarial examples found by
our algorithm with amateur human Go players and 90\% of examples indeed lead
the Go agent to play an obviously inferior action. Our code is available at
\url{https://PaperCode.cc/GoAttack}.Comment: Accepted by Neurips 202
Analysis of Affinely Equivalent Boolean Functions
By walsh
transform, autocorrelation function, decomposition, derivation and
modification of truth table, some new invariants are obtained.
Based on invariant theory, we get two results: first a general
algorithm which can be used to judge if two boolean functions are
affinely equivalent and to obtain the affine equivalence
relationship if they are equivalent. For example, all 8-variable
homogenous bent functions of degree 3 are classified into 2
classes; second, the classification of the Reed-Muller code
which can be used to almost
enumeration of 8-variable bent functions
Extracting the Quantum Geometric Tensor of an Optical Raman Lattice by Bloch State Tomography
In Hilbert space, the geometry of the quantum state is identified by the
quantum geometric tensor (QGT), whose imaginary part is the Berry curvature and
real part is the quantum metric tensor. Here, we propose and experimentally
implement a complete Bloch state tomography to directly measure eigenfunction
of an optical Raman lattice for ultracold atoms. Through the measured
eigenfunction, the distribution of the complete QGT in the Brillouin zone is
reconstructed, with which the topological invariants are extracted by the Berry
curvature and the distances of quantum states in momentum space are measured by
the quantum metric tensor. Further, we experimentally test a predicted
inequality between the Berry curvature and quantum metric tensor, which reveals
a deep connection between topology and geometry
Snowfall Rate Retrieval Using Passive Microwave Measurements and Its Applications in Weather Forecast and Hydrology
(AMSU), Microwave Humidity Sounder (MHS) and Advance Technology Microwave Sounder (ATMS). ATMS is the followon sensor to AMSU and MHS. Currently, an AMSU and MHS based land snowfall rate (SFR) product is running operationally at NOAA/NESDIS. Based on the AMSU/MHS SFR, an ATMS SFR algorithm has also been developed. The algorithm performs retrieval in three steps: snowfall detection, retrieval of cloud properties, and estimation of snow particle terminal velocity and snowfall rate. The snowfall detection component utilizes principal component analysis and a logistic regression model. It employs a combination of temperature and water vapor sounding channels to detect the scattering signal from falling snow and derives the probability of snowfall. Cloud properties are retrieved using an inversion method with an iteration algorithm and a twostream radiative transfer model. A method adopted to calculate snow particle terminal velocity. Finally, snowfall rate is computed by numerically solving a complex integral. The SFR products are being used mainly in two communities: hydrology and weather forecast. Global blended precipitation products traditionally do not include snowfall derived from satellites because such products were not available operationally in the past. The ATMS and AMSU/MHS SFR now provide the winter precipitation information for these blended precipitation products. Weather forecasters mainly rely on radar and station observations for snowfall forecast. The SFR products can fill in gaps where no conventional snowfall data are available to forecasters. The products can also be used to confirm radar and gauge snowfall data and increase forecasters' confidence in their prediction
Strategies for Searching Video Content with Text Queries or Video Examples
The large number of user-generated videos uploaded on to the Internet
everyday has led to many commercial video search engines, which mainly rely on
text metadata for search. However, metadata is often lacking for user-generated
videos, thus these videos are unsearchable by current search engines.
Therefore, content-based video retrieval (CBVR) tackles this metadata-scarcity
problem by directly analyzing the visual and audio streams of each video. CBVR
encompasses multiple research topics, including low-level feature design,
feature fusion, semantic detector training and video search/reranking. We
present novel strategies in these topics to enhance CBVR in both accuracy and
speed under different query inputs, including pure textual queries and query by
video examples. Our proposed strategies have been incorporated into our
submission for the TRECVID 2014 Multimedia Event Detection evaluation, where
our system outperformed other submissions in both text queries and video
example queries, thus demonstrating the effectiveness of our proposed
approaches
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