arXiv subjects

Jin Li

Publications and source records attributed to Jin Li.

316 records · Page 18Linked to original sources

arXiv2012

First observation of $B_s^0\to J/ψη$ and $B_s^0\to J/ψη'$

We report first observations of $B_s^0\to J/ψη$ and $B_s^0\to J/ψη'$. The results are obtained from 121.4 fb^{-1} of data collected at the $Υ(5S)$ resonance with the Belle detector at the KEKB $e^+e^-$ collider. We obtain the branching fractions Br(B_s^0\to J/ψη)= [5.10\pm 0.50(stat.)\pm 0.25(syst.)^{+1.14}_{-0.79}(N_{B_s^(*)\bar B_s^(*))] \times 10^{-4}, and Br(B_s^0\to J/ψη')=[3.71\pm 0.61(stat.)\pm 0.18(syst.)^{+0.83}_{-0.57}(N_{B_s^(*)\bar B_s^(*))] \times 10^{-4}. The ratio of the two branching fractions is measured to be $\frac{Br(B_s\to J/ψη')}{Br(B_s\to J/ψη)} = 0.73\pm 0.14(stat.)\pm 0.02(syst.)$.

hep-ex↗

arXiv2011

Simple Regenerating Codes: Network Coding for Cloud Storage

Network codes designed specifically for distributed storage systems have the potential to provide dramatically higher storage efficiency for the same availability. One main challenge in the design of such codes is the exact repair problem: if a node storing encoded information fails, in order to maintain the same level of reliability we need to create encoded information at a new node. One of the main open problems in this emerging area has been the design of simple coding schemes that allow exact and low cost repair of failed nodes and have high data rates. In particular, all prior known explicit constructions have data rates bounded by 1/2. In this paper we introduce the first family of distributed storage codes that have simple look-up repair and can achieve arbitrarily high rates. Our constructions are very simple to implement and perform exact repair by simple XORing of packets. We experimentally evaluate the proposed codes in a realistic cloud storage simulator and show significant benefits in both performance and reliability compared to replication and standard Reed-Solomon codes.

cs.IT↗

arXiv2011

Dynamics of 2D Stochastic non-Newtonian fluids driven by fractional Brownian motion

A 2D Stochastic incompressible non-Newtonian fluids driven by fractional Bronwnian motion with Hurst parameter $H \in (1/2,1)$ is studied. The Wiener-type stochastic integrals are introduced for infinite-dimensional fractional Brownian motion. Four groups of assumptions, including the requirement of Nuclear operator or Hilbert-Schmidt operator, are discussed. The existence and regularity of stochastic convolution for the corresponding additive linear stochastic equation are obtained under each group of assumptions. Mild solution are then obtained for the non-Newtonian systems by the modified fix point theorem in the selected intersection space. When the domain is square, the random dynamical system generated by non-Newtonian systems has a random attractor under some condition on the spectrum distribution of the corresponding differential operator.

math-ph↗

arXiv2011

Dynamics of stochastic non-Newtonian fluids driven by fractional Brownian motion with Hurst parameter $H \in (1/4,1/2)$

In this paper we consider the Stochastic isothermal, nonlinear, incompressible bipolar viscous fluids driven by a genuine cylindrical fractional Bronwnian motion with Hurst parameter $H \in (1/4,1/2)$ under Dirichlet boundary condition on 2D square domain. First we prove the existence and regularity of the stochastic convolution corresponding to the stochastic non-Newtonian fluids. Then we obtain the existence and uniqueness results for the stochastic non-Newtonian fluids. Under certain condition, the random dynamical system generated by non-Newtonian fluids has a random attractor.

math.DS↗

arXiv2011

Optimal Repair of MDS Codes in Distributed Storage via Subspace Interference Alignment

It is well known that an (n,k) code can be used to store 'k' units of information in 'n' unit-capacity disks of a distributed data storage system. If the code used is maximum distance separable (MDS), then the system can tolerate any (n-k) disk failures, since the original information can be recovered from any k surviving disks. The focus of this paper is the design of a systematic MDS code with the additional property that a single disk failure can be repaired with minimum repair bandwidth, i.e., with the minimum possible amount of data to be downloaded for recovery of the failed disk. Previously, a lower bound of (n-1)/(n-k) units has been established by Dimakis et. al, on the repair bandwidth for a single disk failure in an (n,k) MDS code . Recently, the existence of asymptotic codes achieving this lower bound for arbitrary (n,k) has been established by drawing connections to interference alignment. While the existence of asymptotic constructions achieving this lower bound have been shown, finite code constructions achieving this lower bound existed in previous literature only for the special (high-redundancy) scenario where $k \leq \max(n/2,3)$. The question of existence of finite codes for arbitrary values of (n,k) achieving the lower bound on the repair bandwidth remained open. In this paper, by using permutation coding sub-matrices, we provide the first known finite MDS code which achieves the optimal repair bandwidth of (n-1)/(n-k) for arbitrary (n,k), for recovery of a failed systematic disk. We also generalize our permutation matrix based constructions by developing a novel framework for repair-bandwidth-optimal MDS codes based on the idea of subspace interference alignment - a concept previously introduced by Suh and Tse the context of wireless cellular networks.

cs.IT↗

arXiv2011

Observation of $B_s^0\to J/ψf_0(980)$ and Evidence for $B_s^0\to J/ψf_0(1370)$

We report the first observation of $B_s^0\to J/ψf_0(980)$ and first evidence for $B_s^0\to J/ψf_0(1370)$, which are CP eigenstate decay modes. These results are obtained from $121.4\;\mathrm{fb}^{-1}$ of data collected at the $Υ(5S)$ resonance with the Belle detector at the KEKB $e^+e^-$ collider. We measure the branching fractions $\mathcal{B}(B_s^0\to J/ψf_0(980);f_0(980)\toπ^+π^-)=(1.16^{+0.31}_{-0.19}(\mathrm{stat.})^{+0.15}_{-0.17}(\mathrm{syst.})^{+0.26}_{-0.18}(N_{B_s^{(*)}\bar B_s^{(*)}})) \times 10^{-4}$ with a significance of $8.4σ$, and $\mathcal{B}(B_s^0\to J/ψf_0(1370);f_0(1370)\toπ^+π^-)=(0.34^{+0.11}_{-0.14}(\mathrm{stat.})^{+0.03}_{-0.02}(\mathrm{syst.})^{+0.08}_{-0.05}(N_{B_s^{(*)}\bar B_s^{(*)}})) \times 10^{-4}$ with a significance of $4.2σ$. The last error listed is due to uncertainty in the number of produced $B_s^{(*)}\bar B_s^{(*)}$ pairs.

hep-ex↗

arXiv2009

Inter-Operator Feedback in Data Stream Management Systems via Punctuation

High-volume, high-speed data streams may overwhelm the capabilities of stream processing systems; techniques such as data prioritization, avoidance of unnecessary processing and on-demand result production may be necessary to reduce processing requirements. However, the dynamic nature of data streams, in terms of both rate and content, makes the application of such techniques challenging. Such techniques have been addressed in the context of static and centralized query optimization; however, they have not been fully addressed for data stream management systems. In this work, we present a comprehensive framework that supports prioritization, avoidance of unnecessary work, and on-demand result production over distributed, unreliable, bursty, disordered data sources, typical of many data streams. We propose a form of inter-operator feedback, which flows against the stream direction, to communicate the information needed to enable execution of these techniques. This feedback leverages punctuations to describe the subsets of interest. We identify potential sources of feedback information, characterize new types of punctuation to support feedback, and describe the roles of producers, exploiters, and relayers of feedback that query operators may implement. We present initial experimental observations using the NiagaraST data-stream system.

cs.DB↗

arXiv2008

Radiative Penguin decays at Belle

We present recent progresses in radiative penguin decays of $B$ meson using a large sample of $B\bar{B}$ pairs recorded at the $Υ(4S)$ resonance with the Belle detector at the KEKB asymmetric energy $e^+e^-$ collider. We report precise measurement of inclusive $b\to sγ$ branching ratio with cut $E_γ> 1.7$ GeV, first measurement of time-dependent CP-violation in $B^0\to K_sρ^0γ$, measurement of $B^+\to K^+η'γ$ branching fraction, and improved branching fraction results for $B^0\to(ρ,ω)γ$ with new CP and isospin violation results in the mode.

hep-ex↗

arXiv2002

Research Program of the TEXONO Collaboration: Status and Highlights

This article reviews the research program and efforts for the TEXONO Collaboration among scientists from Taiwan and China. These include reactor-based neutrino physics at the Kuo-Sheng Power Plant in Taiwan as well as various R&D efforts related to the various experimental techniques in neutrino and astro-particle physics.

hep-ex↗

arXiv1998

A Pilot Experiment with Reactor Neutrinos in Taiwan

A Collaboration comprising Taiwan and mainland Chinese scientists has been built up since 1996 to pursue a experimental program in neutrino and astro-particle physics in Taiwan. A pilot experiment to be performed at the Nuclear Power Station II in Taiwan is now under intense preparation. It will make use of a 600 kg CsI(Tl) crystal calorimeter to study various neutrino interactions. The feasibility of performing a long baseline reactor neutrino experiment will also be investigated. The conceptual design and the physics to be addressed by the pilot experiment are presented.

hep-ex↗