Self-configured Elastic Database with Deep Q-Learning Approach

Elastic databases have grown in popularity over conventional databases in recent years due to their ability to be allocated with sufficient capacity for peak load. Especially with the support of the cloud platform, which provides flexible resources and low cost, elastic databases on the cloud show their excellent potential in scalability, flexibility, and accessibility. However, the interaction between the cloud layers of virtual machines (VMs) and databases further complicates the issue of cloud configuration to adapt to dynamic workloads. In this paper, I explore a framework for a self-configured elastic database that can optimize the cloud configuration and adaptively allocate resources under the constraints of databases\u27 Service Level Agreement (SLA). At the core of the framework is a Deep Q learning approach, which combines the advantages of Reinforcement Learning (RL) and Deep Learning (DL). The framework is built on Amazon Web Service (AWS)\u27s cloud environment and uses MySQL database for its high availability replication mechanism. Experimental results on the TPC-W benchmark demonstrate that with the implementation of Deep Q learning, the elastic database reduces SLA violation by more than 90\%, in the response to the steep slope of workload change

China's economic reforms : pointers for other economies in transition?

China's two main economic problems before reform were low incentives to workers and the misallocation of resources among sectors. These problems were theresult of a development strategy oriented toward heavy industry. By improving material incentives, China's reforms created a flow of new resources and allowed them to be allocated to sectors suppressed under pre-reform strategies. The onset of reform in China was not allowed to disrupt production from existing resources. Instead, the newly created resources were permitted to accrue and to flow into the more productive, often light industrial sectors, thus stimulating continuous growth of the national economy during reform. Low incentives and the suppression of nonpriority sectors are common features of the legacy of economies in transition from central planning that based their development on the rapid growth of heavy industry. China's approach may be of interest to them. Among lessons China learned are that: (a) Autonomy must be granted to micromanagement units and preserved to improve the incentive structure and create a new flow of resources. (b) While maintaining essential minimum levels of production in the pre-reform priority sectors, autonomous enterprises must be permitted and encouraged to allocate new incremental resource flows to the previously suppressed sectors. (c) In parallel, the distorted policy environment and planned-allocation system must be progressively reformed to bring them into line with the new system of incentives and modus operandi of autonomous enterprises.Banks&Banking Reform,Municipal Financial Management,Water and Industry,Economic Theory&Research,Environmental Economics&Policies

Light controlling light in a coupled cavity-atom system

We present a theoretical model of light controlling light in a multi-atom cavity QED system consisting of three-level atoms confined in a cavity and interacting with a control laser from free space. A signal laser is coupled into the cavity and provides two output light channels: the transmitted signal light through the cavity and the reflected signal light from the cavity. We show that with the cavity electromagnetically induced transparency manifested by the free-space control light, the amplitude and the phase of the intra-cavity signal light can be manipulated by the free-space control laser. We analyze the cavity transmitted signal light and the cavity reflected signal light, and show that the two output channels of the signal light are complementary and the cavity-atom system is a versatile system for studies of alloptical switching and cross-phase modulation at low control intensities

On Fila-King Conjecture in Dimension Four

We consider the following Cauchy problem for the four-dimensional energy critical heat equation \begin{equation*} \begin{cases} u_t=\Delta u+u^{3} ~&\mbox{ in }~ {\mathbb R}^4 \times (0,\infty),\\ u(x,0)=u_0(x) ~&\mbox{ in }~ {\mathbb R}^4. \end{cases} \end{equation*} We construct a positive infinite time blow-up solution $u(x,t)$ with the blow-up rate $\| u(\cdot,t)\|_{L^\infty({\mathbb R}^4)} \sim \ln t$ as $t\to \infty$ and show the stability of the infinite time blow-up. This gives a rigorous proof of a conjecture by Fila and King \cite[Conjecture 1.1]{filaking12}.Comment: 61 pages; any comment welcom

Trichotomy dynamics of the 1-equivariant harmonic map flow

For the 1-equivariant harmonic map flow from $R^2$ into $S^2$ \begin{equation*} \left\{ \begin{aligned} &v_t=v_{rr}+\frac{v_r}{r} - \frac{\sin(2v)}{2r^2} , ~\quad(r,t)\in R_+\times (t_0,+\infty),\\ &v(r,t_0)=v_0, \qquad\qquad\qquad\quad r\in R_+, \end{aligned} \right. \end{equation*} we construct global growing, bounded and decaying solutions with the initial data $v_0(r)$ satisfying v_0(0)=\pi ~\mbox{ and }~ v_0(r)\sim r^{1-\gamma} ~\mbox{ as }~ r\to+\infty, \quad \gamma>1. These global solutions exhibit the following trichotomy long-time asymptotic behavior \begin{equation*} \| v_r(\cdot,t) \|_{L^\infty ([0,\infty))} \sim \begin{cases} t^{\frac{\gamma-2}{2}}\ln t ~&\mbox{ if }~ 1<\gamma<2,\\ 1 ~&\mbox{ if }~ \gamma=2,\\ \ln t ~&\mbox{ if }~ \gamma>2,\\ \end{cases} ~\mbox{ as }~ t\to +\infty. \end{equation*}Comment: 30 pages; comments welcom

Coherent manipulation of quantum states in a coupled cavity-atom system

We study atomic coherence and interference in four-level atoms confined in an optical cavity and explores the interplay between cavity QED and electromagnetically induced transparency (EIT). The destructive interference can be induced in the coupled cavityatom system with a free-space control laser tuned to the normal mode resonance and leads to suppression of the normal mode excitation. Then by adding a pump laser coupled to the four-level atoms from free space, the control-laser induced destructive interference can be reversed and the normal mode excitation is restored. When the free-space control laser is tuned to the atomic resonance and forms a Λ-type EIT configuration with the cavity-atom system, EIT is manifested as a narrow transmission peak of a weak probe laser coupled into the cavity mode. With the free-space pump laser driving the cavity-confined atoms in a four-level configuration, the narrow transmission peak of the cavity EIT can be split into two peaks and the dressed intra-cavity dark states are created analogous to the dressed states in free space. We report experimental studies of such coherently coupled cavityatom system realized with cold Rb atoms confined in an optical cavity and discuss possible applications in quantum nonlinear optics and quantum information science

Parallel and progressive approaches for skyline query over probabilistic incomplete database

The advanced productivity of the modern society has created a wide range of similar commodities. However, the descriptions of commodities are always incomplete. Therefore, it is difficult for consumers to make choices. In the face of this problem, skyline query is a useful tool. However, the existing algorithms are unable to address incomplete probabilistic databases. In addition, it is necessary to wait for query completion to obtain even partial results. Furthermore, traditional skyline algorithms are usually serial. Thus, they cannot utilize multi-core processors effectively. Therefore, a parallel progressive skyline query algorithm for incomplete databases is imperative, which provides answers gradually and much faster. To address these problems, we design a new algorithm that uses multi-level grouping, pruning strategies, and pruning tuple transferring, which significantly decreases the computational costs. Experimental results demonstrate that the skyline results can be obtained in a short time. The parallel efficiency for an Octa-core processor reaches 90% on high-dimensional, large databases.<br /