88 research outputs found

    Analytical Properties for the Fifth Order Camassa-Holm (FOCH) Model

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    This paper devotes to present analysiswork on the fifth order Camassa-Holm (FOCH) modelwhich recently proposed by Liu and Qiao. Firstly, we establish the local and global existence of the solution to the FOCH model. Secondly, we study the property of the infinite propagation speed. Finally, we discuss the long time behavior of the support of momentum density with a compactly supported initial data

    Incipient Slip-Based Rotation Measurement via Visuotactile Sensing During In-Hand Object Pivoting

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    In typical in-hand manipulation tasks represented by object pivoting, the real-time perception of rotational slippage has been proven beneficial for improving the dexterity and stability of robotic hands. An effective strategy is to obtain the contact properties for measuring rotation angle through visuotactile sensing. However, existing methods for rotation estimation did not consider the impact of the incipient slip during the pivoting process, which introduces measurement errors and makes it hard to determine the boundary between stable contact and macro slip. This paper describes a generalized 2-d contact model under pivoting, and proposes a rotation measurement method based on the line-features in the stick region. The proposed method was applied to the Tac3D vision-based tactile sensors using continuous marker patterns. Experiments show that the rotation measurement system could achieve an average static measurement error of 0.17 degree and an average dynamic measurement error of 1.34 degree. Besides, the proposed method requires no training data and can achieve real-time sensing during the in-hand object pivoting.Comment: 7 pages, 9 figures, submitted to ICRA 202

    Rogue peakon, well-posedness, ill-posedness and blow-up phenomenon for an integrable Camassa-Holm type equation

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    In this paper, we study an integrable Camassa-Holm (CH) type equation with quadratic nonlinearity. The CH type equation is shown integrable through a Lax pair, and particularly the equation is found to possess a new kind of peaked soliton (peakon) solution - called {\sf rogue peakon}, that is given in a rational form with some logarithmic function, but not a regular traveling wave. We also provide multi-rogue peakon solutions. Furthermore, we discuss the local well-posedness of the solution in the Besov space Bp,rsB_{p,r}^{s} with 1p,r1\leq p,r\leq\infty, s>max{1+1/p,3/2}s>\max \left\{1+1/p,3/2\right\} or B2,13/2B_{2,1}^{3/2}, and then prove the ill-posedness of the solution in B2,3/2B_{2,\infty}^{3/2}. Moreover, we establish the global existence and blow-up phenomenon of the solution, which is, if m0(x)=u0u0xx(≢)0m_0(x)=u_0-u_{0xx}\geq(\not\equiv) 0, then the corresponding solution exists globally, meanwhile, if m0(x)(≢)0m_0(x)\leq(\not\equiv) 0, then the corresponding solution blows up in a finite time.Comment: 23 pages, 6 figure

    On the Cauchy Problem for the b

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    In this paper, we consider b-family equations with a strong dispersive term. First, we present a criterion on blow-up. Then global existence and persistence property of the solution are also established. Finally, we discuss infinite propagation speed of this equation

    Zero-shot Domain Adaptation for Neural Machine Translation with Retrieved Phrase-level Prompts

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    Domain adaptation is an important challenge for neural machine translation. However, the traditional fine-tuning solution requires multiple extra training and yields a high cost. In this paper, we propose a non-tuning paradigm, resolving domain adaptation with a prompt-based method. Specifically, we construct a bilingual phrase-level database and retrieve relevant pairs from it as a prompt for the input sentences. By utilizing Retrieved Phrase-level Prompts (RePP), we effectively boost the translation quality. Experiments show that our method improves domain-specific machine translation for 6.2 BLEU scores and improves translation constraints for 11.5% accuracy without additional training

    Advances in genetic factors of adolescent idiopathic scoliosis: a bibliometric analysis

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    ObjectiveThis study offers a bibliometric analysis of the current situation, hotspots, and cutting-edge domains of genetic factors of adolescent idiopathic scoliosis (AIS).MethodsAll publications related to genetic factors of AIS from January 1, 1992, to February 28, 2023, were searched from the Web of Science. CiteSpace software was employed for bibliometric analysis, collecting information about countries, institutions, authors, journals, and keywords of each article.ResultsA cumulative number of 308 articles have been ascertained. Since 2006, publications relating to genetic factors of AIS have significantly increased. China leads in both productivity and influence in this area, with the Chinese Academy of Medical Sciences being the most productive institution. The most prolific scholars in this field are Y. Qiu and Z. Z. Zhu. The publications that contributed the most were from Spine and European Spine Journal. The most prominent keywords in the genetic factors of AIS were “fibrillin gene”, “menarche”, “calmodulin”, “estrogen receptor gene”, “linkage analysis”, “disc degeneration”, “bone mineral density”, “melatonin signaling dysfunction”, “collagen gene”, “mesenchymal stem cell”, “LBX1”, “promoter polymorphism”, “Bone formation”, “cerebrospinal fluid flow” and “extracellular matrix”.ConclusionThis analysis provides the frontiers and trends of genetic factors in AIS, including relevant research, partners, institutions and countries

    Double Trouble of Air Pollution by Anthropogenic Dust

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    With urbanization worldwide in recent decades, anthropogenic dust (AD) emissions due to heavy urban construction and off-road vehicle use have been increasing. Its perturbations on urban air pollution at the global scale are still unclear. Based on observations, we found that a high urban AD optical depth is often accompanied by severe non-dust aerosol optical depth in the planetary boundary layer (PBL), both magnitudes even comparable. To investigate the causes, an AD emission inventory constrained by satellite retrievals is implemented in a global climate model. The results show that AD-induced surface radiative cooling of up to -15.9 +/- 4.0 W m(-2) regionally leads to reduced PBL height, which deteriorates non-dust pollution, especially over India and northern China, in addition to the tremendous direct AD contribution to pollutants. The estimated global total premature mortality due to AD is 0.8 million deaths per year and is more severe in populous regions.Peer reviewe
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