• Title/Summary/Keyword: Cluster State

Search Result 399, Processing Time 0.028 seconds

SEPARATION AXIOMS ON BI-GENERALIZED TOPOLOGICAL SPACES

  • Ray, A. Deb;Bhowmick, Rakesh
    • Journal of the Chungcheong Mathematical Society
    • /
    • v.27 no.3
    • /
    • pp.363-379
    • /
    • 2014
  • In this paper, introducing various separation axioms on a bi-GTS, it has been observed that such separation axioms actually unify the well-known separation axioms on topological spaces. Several characterizations of such separation properties of a bi-GTS are established in terms of ${\gamma}_{{\mu}_i,{\mu}_j}$-closure operator, generalized cluster sets of functions and graph of functions.

Ab initio Electronic Structure Calculations of $O_2$ Using Coupled Cluster Approaches and Many-Body Perturbation Theory

  • Yoon Sup Lee;Sang Yeon Lee
    • Bulletin of the Korean Chemical Society
    • /
    • v.12 no.2
    • /
    • pp.211-213
    • /
    • 1991
  • The ground state of the oxygen molecule is calculated by various methods of coupled cluster approaches and many body perturbation theory using a double zeta plus polarization basis set and the UHF reference state. All the methods employed are capable of describing the oxygen molecule near the equilibrium bond length and the separated atom, but do not correctly depict the breaking of the multiple bond. For this basis set, including more correlations does not necessarily improve the agreement with experiment for molecular properties such as bond lengths and dissociation energies.

Energy Efficient Topology Control based on Sociological Cluster in Wireless Sensor Networks

  • Kang, Sang-Wook;Lee, Sang-Bin;Ahn, Sae-Young;An, Sun-Shin
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.6 no.1
    • /
    • pp.341-360
    • /
    • 2012
  • The network topology for a wide area sensor network has to support connectivity and a prolonged lifetime for the many applications used within it. The concepts of structure and group in sociology are similar to the concept of cluster in wireless sensor networks. The clustering method is one of the preferred ways to produce a topology for reduced electrical energy consumption. We herein propose a cluster topology method based on sociological structures and concepts. The proposed sociological clustering topology (SOCT) is a method that forms a network in two phases. The first phase, which from a sociological perspective is similar to forming a state within a nation, involves using nodes with large transmission capacity to set up the global area for the cluster. The second phase, which is similar to forming a city inside the state, involves using nodes with small transmission capacity to create regional clusters inside the global cluster to provide connectivity within the network. The experimental results show that the proposed method outperforms other methods in terms of energy efficiency and network lifetime.

Abell 2261: a fossil galaxy cluster in a transition phase

  • Kim, Hyowon;Ko, Jongwan;Kim, Jae-woo;Smith, Rory;Song, Hyunmi;Hwang, Ho Seong
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.43 no.1
    • /
    • pp.58.2-58.2
    • /
    • 2018
  • Fossil groups of galaxies have characteristic features of a dominant central elliptical galaxy (${\Delta}M_{12}$ > 2 in $0.5R_{vir}$) embedded in highly relaxed X-ray halo, which indicates dynamically stable and evolved systems. These are thought as a final stage of the evolution of galaxy groups in the hierarchical structure formation scenario. However, the formation and evolution of fossil clusters are still unclear due to lack of detailed studies. Therefore, we perform a kinematic research of a known fossil cluster Abell 2261 (A2261 hereafter) using spectroscopic data of 589 galaxies in the A2261 field. Even though A2261 is known as a fossil cluster, previous studies found several unusual features such as quite high X-ray entropy for a stable cluster, and an elongated shape, which are not expected in standard fossil clusters. Using the caustic method, we identify cluster member galaxies and discover a second bright galaxy (${\Delta}M_{12}=1.68$) at ${\sim}1.5R_{vir}$. The presence of such a bright galaxy can break the current fossil state of cluster in the near future. In addition, with two independent substructure finding methods, we confirm that the previously detected elongated galaxy distribution of the cluster is a real feature. These findings indicate that A2261 is not in a fully stable state, unlike the existing fossil definition diagnostic. We require a more stringent criterion for the fossil definition to represent a genuinely final stage of cluster evolution.

  • PDF

An Arbitrary Disk Cluster Manipulating Method for Allocating Disk Fragmentation of Filesystem (파일시스템의 클러스터를 임의로 할당하여 디스크를 단편화하기 위한 방법)

  • Cho, Gyu-Sang
    • Journal of Korea Society of Digital Industry and Information Management
    • /
    • v.16 no.2
    • /
    • pp.11-25
    • /
    • 2020
  • This study proposes a method to manipulate fragmentation of disks by arbitrarily allocating and releasing the status of a disk cluster in the NTFS file system. This method allows experiments to be performed in several studies related to fragmentation problems on disk cluster. Typical applicable research examples include testing the performance of disk defragmentation tools according to the state of fragmentation, establishing an experimental environment for fragmented file carving methods for digital forensics, setting up cluster fragmentation for testing the robustness of data hiding methods within directory indexes, and testing the file system's disk allocation methods according to the various version of Windows. This method suggests how a single file occupies a cluster and presents an algorithm with a flowchart. It raises three tricky problems to solve the method, and we propose solutions to the problems. Experiments for allocating the disk cluster to be fragmented to the maximum extent possible, it then performs a disk defragmentation experiment to prove the proposed method is effective.

Position of Source Leaf Affects Translocation and Distribution of $C^{14}$ Photo-Assimilates in Tomato

  • Lee Sang-Gyu;Lee Chiwon W.
    • Journal of Bio-Environment Control
    • /
    • v.15 no.2
    • /
    • pp.173-176
    • /
    • 2006
  • The relationship between source leaf position and photo-assimilate translocation and distribution was characterized for tomato (Lycopersicon esculentum Mill) grown in the greenhouse. Three different positions of source leaf on the stem (first node above or below the first fruit cluster and $5^{th}$ node above the first fruit cluster) were tested for their influence on $^{14}CO_2$ assimilation and transfer to different parts of the plant. The leaves at the $5^{th}$ node above the first fruit cluster transferred the highest (57%) proportion of $C^{14}$ to other plant parts, followed by leaves home on the first node below the first fruit cluster (50%), and the first node above the first fruit cluster (39%). In all treatments, fruits served as the strongest sink for $C^{14}$, followed by stem, leaf, and root tissues. The leaf home on the $5^{th}$ node above the first fruit cluster transferred the largest amount of $C^{14}$ to the second fruit cluster.

Architecture Modeling of a Performance Report Tool for a Cluster System (클러스터 시스템의 성능 레포트 툴의 아키텍처 모델링)

  • Kim, Ki;Choi, Eun-Mi
    • Proceedings of the Korea Society for Simulation Conference
    • /
    • 2003.06a
    • /
    • pp.67-71
    • /
    • 2003
  • In order to manage a cluster system that consists of a number servers, management aspects such as configuration management, fault management, performance management, and user management should be considered. Especially, it is necessary to monitor performances for performance and fault management. An agent in each server collects performance counters, status changes, and events occurred in normal or abnormal states. The data collected are delivered to a collector sorter and processed in a report tool for performance analysts and management decision in the cluster system point of view, by detecting fault state and tracing out resource usage, service response, and response, and states until failed. In this paper we propose an architecture modeling of a performance report tool for proactive cluster system management. Some results on a cluster system are presented.

  • PDF

Phase Space as a Tool for Understanding Galaxy Cluster Environmental Effects

  • Smith, Rory;Rhee, Jin Su;Choi, Hoseung;Yi, Sukyoung
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.41 no.1
    • /
    • pp.34.3-35
    • /
    • 2016
  • A galaxy-cluster phase space diagram is a simple plot of clustocentric velocity versus clustocentric radius for each member of the cluster. Using state-of-the-art, cosmological hydrodynamical simulations, we investigate where simulated galaxies fall in phase space. We find the galaxies with different cluster infall times often separate cleanly in phase space. We also investigate how a galaxy's location in phase space is correlated with its tidal mass loss, and ram pressure stripping. By comparing our simulated cluster galaxies to observed cluster galaxies, we show how phase space diagrams are essential tools for understanding environmental effects acting on cluster galaxies.

  • PDF

MOLECULAR DYNAMICS SIMULATION OF THE INTERACTION BETWEEN CLUSTER BEAMS AND SOLID SURFACES

  • Kang, Hee-Jae;Lee, Min-Wha;Whang, Chung-Nam
    • Journal of the Korean Vacuum Society
    • /
    • v.4 no.S2
    • /
    • pp.139-147
    • /
    • 1995
  • The mechanism of the ionized cluster beam deposition has been studied using Molecular Dynamics Simulation. The Embedded Atom Method(EAM) potential were used in the simulation. The impact of a Au95-cluster on Au(100) substrate was studied for the impact energies 0.15-10eV/atom. The dependency of the impact energy of cluster beam was observed. For the cluster energy impact of 10eV per atom, the defects on surface were created and the cluster embedded into substrate as an amorphous state. For the energy of 0.5eV per atom, the defect free homoepitaxial growth was observed and atomic scale nucleation was formated, which are in good agreement with experiment. Thus molecular dynamics simulation is very useful to study the mechanism of the ionized cluster beam deposition.

  • PDF

Modified Analytic Solutions of F.C.C. Metal Clusters

  • Juhyeok Lee;Hojing Kim
    • Bulletin of the Korean Chemical Society
    • /
    • v.14 no.5
    • /
    • pp.578-583
    • /
    • 1993
  • By including the overlap integrals between atomic orbitals, the modified cluster orbitals for a metal cluster of face centered cubic lattice are found. The modified analytic solutions of the cluster are obtained from them with the assumption that the cluster orbitals with different state indices do not mix together. The physical properties-the HOMO levels and the unit electronic energies-of Ni, Pd, and Pt clusters of various size, calculated by the modified cluster orbital method, agree better with the results obtained by the Extended Huckel calculation than those of the previous(unmodified) cluster orbital method do. As a result, it is verified that the physical properties, at least those related to the energy levels, obtained by the Extended Huckel method may be reproduced by use of the modified cluster orbital method instead.