1,495 research outputs found
Error estimates of a bi-fidelity method for a multi-phase Navier-Stokes-Vlasov-Fokker-Planck system with random inputs
Uniform error estimates of a bi-fidelity method for a kinetic-fluid coupled
model with random initial inputs in the fine particle regime are proved in this
paper. Such a model is a system coupling the incompressible Navier-Stokes
equations to the Vlasov-Fokker-Planck equations for a mixture of the flows with
distinct particle sizes. The main analytic tool is the hypocoercivity analysis
for the multi-phase Navier-Stokes-Vlasov-Fokker-Planck system with
uncertainties, considering solutions in a perturbative setting near the global
equilibrium. This allows us to obtain the error estimates in both kinetic and
hydrodynamic regimes
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Point-of-Sale Marketing in Recreational Marijuana Dispensaries Around California Schools.
PurposeAfter marijuana commercialization, the presence of recreational marijuana dispensaries (RMDs) was rapidly increasing. The point-of-sale marketing poses concerns about children's exposure. This study examined advertising and promotions that potentially appeal to children and access restrictions in RMDs around California schools.MethodsThis was a cross-sectional and observational study conducted from June to September 2018. Trained fieldworkers audited retail environments in 163 RMDs in closest proximity to 333 randomly sampled public schools in California.ResultsAbout 44% of schools had RMDs located within 3 miles. Regarding interior marketing, 74% of RMDs had at least one instance of child-appealing products, packages, paraphernalia, or advertisements. RMDs closer to a school had a higher proportion with interior child-appealing marketing. More than three fourths of RMDs had generic promotional activities; particularly, 28% violated the free-sample ban. Regarding exterior marketing, only 2% of RMDs had those appealing to children. More than 60% of RMDs had exterior signs indicative of marijuana. Approximately, one-third had generic advertisements, and 13% had advertisements bigger than 1,600 square inches. Regarding access restrictions, almost all RMDs complied with age verification, but 84% had no age limit signs, and only 40% had security personnel.ConclusionsDespite minimal point-of-sale marketing practices appealing to children on the exterior of RMDs around California schools, such practices were abundant on the interior. Marketing practices not specifically appealing to children were also common on both the interior and exterior of RMDs. Dispensaries' violation of age verification law, lack of security personnel, and presence of child-appealing marketing should be continuously monitored and prevented
UniX-Encoder: A Universal -Channel Speech Encoder for Ad-Hoc Microphone Array Speech Processing
The speech field is evolving to solve more challenging scenarios, such as
multi-channel recordings with multiple simultaneous talkers. Given the many
types of microphone setups out there, we present the UniX-Encoder. It's a
universal encoder designed for multiple tasks, and worked with any microphone
array, in both solo and multi-talker environments. Our research enhances
previous multi-channel speech processing efforts in four key areas: 1)
Adaptability: Contrasting traditional models constrained to certain microphone
array configurations, our encoder is universally compatible. 2) Multi-Task
Capability: Beyond the single-task focus of previous systems, UniX-Encoder acts
as a robust upstream model, adeptly extracting features for diverse tasks
including ASR and speaker recognition. 3) Self-Supervised Training: The encoder
is trained without requiring labeled multi-channel data. 4) End-to-End
Integration: In contrast to models that first beamform then process
single-channels, our encoder offers an end-to-end solution, bypassing explicit
beamforming or separation. To validate its effectiveness, we tested the
UniX-Encoder on a synthetic multi-channel dataset from the LibriSpeech corpus.
Across tasks like speech recognition and speaker diarization, our encoder
consistently outperformed combinations like the WavLM model with the BeamformIt
frontend.Comment: Submitted to ICASSP 202
Resilient Output Consensus Control of Heterogeneous Multi-agent Systems against Byzantine Attacks: A Twin Layer Approach
This paper studies the problem of cooperative control of heterogeneous
multi-agent systems (MASs) against Byzantine attacks. The agent affected by
Byzantine attacks sends different wrong values to all neighbors while applying
wrong input signals for itself, which is aggressive and difficult to be
defended. Inspired by the concept of Digital Twin, a new hierarchical protocol
equipped with a virtual twin layer (TL) is proposed, which decouples the above
problems into the defense scheme against Byzantine edge attacks on the TL and
the defense scheme against Byzantine node attacks on the cyber-physical layer
(CPL). On the TL, we propose a resilient topology reconfiguration strategy by
adding a minimum number of key edges to improve network resilience. It is
strictly proved that the control strategy is sufficient to achieve asymptotic
consensus in finite time with the topology on the TL satisfying strongly
-robustness. On the CPL, decentralized chattering-free controllers are
proposed to guarantee the resilient output consensus for the heterogeneous MASs
against Byzantine node attacks. Moreover, the obtained controller shows
exponential convergence. The effectiveness and practicality of the theoretical
results are verified by numerical examples
Research Progress of Metabolic Syndrome and Renal Cancer
Metabolic syndrome (MS) is a condition of metabolic abnormalities in genetically predisposed individuals that are caused by lifestyle habits such as consumption of diet rich in fat and lack of exercise. Few major symptoms include abnormal glucose tolerance, hypertension, abnormal lipid metabolism (including high triglycerides in the blood, low high density lipoprotein cholesterol, etc.), obesity, etc. Although metabolic syndrome has been found to be mainly related to cardiovascular diseases, diabetes, malignancy and other diseases, in recent years, more and more evidence has shown that MS is closely related to the occurrence, development and prognosis of kidney cancer, among which obesity and hypertension have been identified as major risk factors for kidney cancer. This article reviews the research progress on the relationship between MS and its components and the risk, invasiveness, and prognosis of renal carcinoma, so as to provide reference for the prevention, diagnosis, treatment and prognosis of renal cancer
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