• Title/Summary/Keyword: global snapshot

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An Efficient Tree-Based Algorithm for the Distributed Trigger Counting Problem (분산 트리거 계수 문제를 위한 효율적인 트리 기반 알고리즘)

  • Lee, Jae Heung
    • Smart Media Journal
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    • v.10 no.4
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    • pp.15-20
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    • 2021
  • The distributed trigger counting problem is to notify the user when the total number of triggers received from a distributed system consisting of n nodes reaches a predefined value w. The distributed trigger counting problem is used for monitoring and global snapshots in various distributed systems. In this paper, we propose a simple and efficient algorithm for the distributed trigger counting problem. The proposed algorithm operates based on a tree structure of degree $\sqrt{n}$ and height 2. The proposed algorithm operates in three different phases based on the remaining number of triggers. Experimental results show that the proposed algorithm has a smaller message complexity than CoinRand, and MaxRcv also performed better when the number of nodes is not large.

Largest Array SKA and Largest Dish FAST

  • Peng, Bo
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.2
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    • pp.234.1-234.1
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    • 2012
  • The largest array SKA (Square Kilometre Array) project was proposed by astronomers from 10 countries, and first coordinated by the LTWG (Large Telescope Working Group) formed at the General Assembly of URSI (International Union of Radio Science) in 1993. It enters the pre-construction phase (2012-2015), towards the 10% SKA construction (2016-2019) called SKA1 and the rest of SKA (2019-2023) called SKA 2, under the leadership of the SKA Organisation (SKAO) established on November 23, 2011. I will review the Chinese participation in the SKA project at national, regional and global levels in the past two decades. During such a Long March to the SKA, a number of national Megascience projects have taken root and have been (are being) successfully constructed, with costs at the 100 M US dollar level, including the largest dish FAST (Five-hundred meter Aperture Spherical Telescope), which can be seen as a forerunner of the KARST (Kilometre Area Radio Synthesis Telescope) project, being as one of the two LDSN (Large Diameter Small Number) concepts for realizing the SKA. A close look at the FAST project gives an impressive snapshot of the construction phase in China.

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Presidential Public Diplomacy 2.0: Seven Lessons to Prevent Fire in Cyberspace

  • dos Santos, Niedja de Andrade e Silva Forte
    • Journal of Public Diplomacy
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    • v.1 no.1
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    • pp.36-56
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    • 2021
  • The Amazon fires in summer 2019 triggered an incendiary Twitter debate between French president Emmanuel Macron and Brazilian president Jair Bolsonaro that engaged political leaders, celebrities, and audiences worldwide. Currently, diplomats-in-chief connect to the global public through completely open debates, often without proper advice from foreign-affairs ministers, which may result in misunderstandings and conflicts among world leaders. Hence, this study argues that these interactions must be supported by Nicholas Cull's seven lessons in public diplomacy. The main topic on hand is presidential public diplomacy performed through digital means in cyberspace. Thus, after distinguishing cyberspace, digital diplomacy, and cyberdiplomacy, the literature review focuses on presidential public diplomacy, presidential diplomacy on Twitter, and Cull's seven lessons. Subsequently, the case study method provides a snapshot of the debate between Macron and Bolsonaro over the Amazon fires. This study concludes by answering the research question and indicating grist for the mill with regard to future developments.

Classification of the Efficacy of Herbal Medicine Alterations in Neuronal Hypoxia Models through Analysis of Gene Expression

  • Hwang, Joo-Won;Shin, Gil-Cho;Moon, Il-Su
    • The Journal of Korean Medicine
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    • v.35 no.4
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    • pp.36-51
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    • 2014
  • Objectives: cDNA microarray is an effective method to snapshot gene expression. Functional clustering of gene expressions can identify herbal medicine mechanisms. Much microarray data is available for various herbal medicines. This study compares regulated genes with herbal medicines to evaluate the nature of the drugs. Methods: Published microarray data were collected. Total RNAs were prepared from dissociated hippocampal dissociate cultures which were given hypoxic shock in the presence of each herbal medicine. Up- or downregulated genes higher than Global M value 0.5 were selected, clustered in functional groups, and compared with various herbal treatments. Results: 1. Akt2 was upregulated by Acorus gramineus SOLAND, Arisaema amurense var. serratum $N_{AKAI}$ and Coptis chinensis $F_{RANCH}$, and they belong to Araceae herb. 2. Nf-${\kappa}b1$, Cd5, $Gn{\gamma}7$ and Sgne1 were upregulated by Arisaema amurense var. serratum $N_{AKAI}$, Coptis chinensis $F_{RANCH}$ and Rheum coreanum $N_{AKAI}$. 3. Woohwangcheongsim-won, Sohaphyang-won and Scutellaria baicalensis $G_{EORGI}$ downregulated Scp2 and upregulated Tsc2. Woohwangcheongsim-won and Sohaphyang-won upregulated Hba1 and downregulated Myf6. 4. Sohaphyang-won and Scutellaria baicalensis $G_{EORGI}$ downregulated Slc12a1. 5. Woohwangcheongsim-won and Arisaema amurense var. serratum $N_{AKAI}$ upregulated $Rar{\alpha}$, Woohwangcheongsim-won and Coptis chinensis $F_{RANCH}$ downregulated Rab5a and $Pdgfr{\alpha}$, and Woohwangcheongsim-won and Rheum coreanum $N_{AKAI}$ upregulated $Plc{\gamma}1$ and downregulated Pla2g1b and Slc10a1. Conclusions: By clustering microarray, genes are commonly identified to be either up- or downregulated. These results will provide new information to understand the efficacy of herbal medicines and to classify them at the molecular level.

A Mapping Method for a Logical Volume Manager in SAN Environment (SAN 논리볼륨 관리자를 위한 매핑 기법)

  • 남상수;송석일;유재수;김창수;김명준
    • Journal of KIISE:Computing Practices and Letters
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    • v.9 no.6
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    • pp.718-731
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    • 2003
  • SAN(Storage Area Network) was developed in response to the requirements of high availability of data, scalable growth, and system performance. In order to use the SAN more efficiently, most of the SAN operating software supports storage virtualization concepts that allow users to view physical storage devices of the SAN as a large volume. A logical volume manager plays a key role in storage virtualization. It realizes the storage virtualization by mapping logical addresses to physical addresses. In this paper, we design and implement an efficient and flexible mapping method for the logical volume manager. Additionally we also design and implement a free space management method for flexible mapping. Our mapping method supports a snapshot that preserves a volume image at certain time and on-line reorganization to allow users to add or remove storage devices to and from the SAN even while the system is running. To justify our mapping method, we compare it with the mapping method of the GFS (Global File System) through various experiments.

Children's Understanding of the World and a Rationale for a World Geography Curriculum (초등학생들의 세계에 대한 인지 특성과 세계지리 교육과정 구성의 전제)

  • Song, Un-Gun;Kim, Jae-Il
    • Journal of the Korean association of regional geographers
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    • v.8 no.3
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    • pp.364-379
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    • 2002
  • The purpose of this study is to search for a rationale of world geography curriculum. Elementary school children tend to get impressionistic and distorted information about other countries through snapshot TV programs. But they need to get more balanced understanding about them from the perspective of each country. Children's judgment about other countries, favorable or unfavorable, tends to be emotional, based on the first-order conditions of life in those regions, such as atmosphere, food, and habitat, and the symbolics of the place. But their systematic understanding about the relationship between their own life and the life of other locations or countries tends to be meager. It seems to be partly due to the practice of co-centric curricular construction. The geography curriculum may have to be in relation to other countries, from the regional geography of the third grade on.

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Trends Analysis on Research Articles in the Journal of Korean Society for Information Management (『정보관리학회지』 연구의 동향분석)

  • Seo, Eun-Gyoung
    • Journal of the Korean Society for information Management
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    • v.27 no.4
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    • pp.7-32
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    • 2010
  • The aims of this study were to provide a global overview of research trends in information science and to trace its changes in the main research topics over time using trends analysis. The study examined the topics of research articles published in Journal of Korean Society for Information Management between 1984 and 2009. Rather than taking a single snapshot of a given point in time, this study attempted to present a series of such pictures in order to identify trends over time. The fairly arbitrary decision was taken to divide the period under consideration into three 'publication windows': 1984-1994, 1995-2002, 2003-2009. The study revealed that the most productive areas were 'Information Service', followed by 'Information Organization', and 'Information System'. The most productive sub-areas were 'Library Service', 'User Study', 'Automatic Document Analysis', 'ILS', 'Thesaurus/Ontology', and 'Digital Library'. From the comparisons of intellectual structures of title keywords, the key research area in the field of Information Science was 'Information Retrieval'. The studies of IT applications and service system evaluation have been expanded.

On the Parcel Loading System of Naive Bayes-LSTM Model Based Predictive Maintenance Platform for Operational Safety and Reliability (Naive Bayes-LSTM 기반 예지정비 플랫폼 적용을 통한 화물 상차 시스템의 운영 안전성 및 신뢰성 확보 연구)

  • Sunwoo Hwang;Jinoh Kim;Junwoo Choi;Youngmin Kim
    • Journal of the Korea Safety Management & Science
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    • v.25 no.4
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    • pp.141-151
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    • 2023
  • Recently, due to the expansion of the logistics industry, demand for logistics automation equipment is increasing. The modern logistics industry is a high-tech industry that combines various technologies. In general, as various technologies are grafted, the complexity of the system increases, and the occurrence rate of defects and failures also increases. As such, it is time for a predictive maintenance model specialized for logistics automation equipment. In this paper, in order to secure the operational safety and reliability of the parcel loading system, a predictive maintenance platform was implemented based on the Naive Bayes-LSTM(Long Short Term Memory) model. The predictive maintenance platform presented in this paper works by collecting data and receiving data based on a RabbitMQ, loading data in an InMemory method using a Redis, and managing snapshot DB in real time. Also, in this paper, as a verification of the Naive Bayes-LSTM predictive maintenance platform, the function of measuring the time for data collection/storage/processing and determining outliers/normal values was confirmed. The predictive maintenance platform can contribute to securing reliability and safety by identifying potential failures and defects that may occur in the operation of the parcel loading system in the future.

A Study on Intelligent Self-Recovery Technologies for Cyber Assets to Actively Respond to Cyberattacks (사이버 공격에 능동대응하기 위한 사이버 자산의 지능형 자가복구기술 연구)

  • Se-ho Choi;Hang-sup Lim;Jung-young Choi;Oh-jin Kwon;Dong-kyoo Shin
    • Journal of Internet Computing and Services
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    • v.24 no.6
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    • pp.137-144
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    • 2023
  • Cyberattack technology is evolving to an unpredictable degree, and it is a situation that can happen 'at any time' rather than 'someday'. Infrastructure that is becoming hyper-connected and global due to cloud computing and the Internet of Things is an environment where cyberattacks can be more damaging than ever, and cyberattacks are still ongoing. Even if damage occurs due to external influences such as cyberattacks or natural disasters, intelligent self-recovery must evolve from a cyber resilience perspective to minimize downtime of cyber assets (OS, WEB, WAS, DB). In this paper, we propose an intelligent self-recovery technology to ensure sustainable cyber resilience when cyber assets fail to function properly due to a cyberattack. The original and updated history of cyber assets is managed in real-time using timeslot design and snapshot backup technology. It is necessary to secure technology that can automatically detect damage situations in conjunction with a commercialized file integrity monitoring program and minimize downtime of cyber assets by analyzing the correlation of backup data to damaged files on an intelligent basis to self-recover to an optimal state. In the future, we plan to research a pilot system that applies the unique functions of self-recovery technology and an operating model that can learn and analyze self-recovery strategies appropriate for cyber assets in damaged states.

Evaluation of Perfusion and Image Quality Changes by Reconstruction Methods in 13N-Ammonia Myocardial Perfusion PET/CT (13N-암모니아 심근관류 PET/CT 검사 시 영상 재구성 방법에 따른 관류량 변화와 영상 평가)

  • Do, Yong Ho;Lee, Hong Jae;Kim, Jin Eui
    • The Korean Journal of Nuclear Medicine Technology
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    • v.18 no.1
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    • pp.69-75
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    • 2014
  • Purpose: The aim of this study was to evaluate changes of quantitative and semi-quantitative myocardial perfusion indices and image quality by image reconstruction methods in $^{13}N$-ammonia ($^{13}N-NH_3$) myocardial perfusion PET/CT. Materials and Methods: Data of 14 (8 men, 6 women) patients underwent rest and adenosine stress $^{13}N-NH_3$ PET/CT (Biograph TruePoint 40 with TrueV, Siemens) were collected. Listmode scans were acquired for 10 minutes by injecting 370MBq of $^{13}N-NH_3$. Dynamic and static reconstruction was performed by use of FBP, iterative2D (2D), iterative3D (3D) and iterative TrueX (TrueX) algorithm. Coronary flow reserve (CFR) of dynamic reconstruction data, extent(%) and total perfusion deficit (TPD) (%) measured in sum of 4-10 minutes scan were evaluated by comparing with 2D method which was recommended by vendor. The image quality of each reconstructed data was compared and evaluated by five nuclear medicine physicians through a blind test. Results: CFR were lower in TrueX 18.68% (P=0.0002), FBP 4.35% (P=0.1243) and higher in 3D 7.91% (P<0.0001). As semi-quantitative values, extent and TPD of stress were higher in 3D 3.07%p (P=0.001), 2.36%p (P=0.0002), FBP 1.93%p (P=0.4275), 1.57%p (P=0.4595), TrueX 5.43%p (P=0.0003), 3.93%p (P<0.0001). Extent and TPD of rest were lower in FBP 0.86%p (P=0.1953), 0.57%p (P=0.2053) and higher in 3D 3.21%p (P=0.0006), 2.57%p (P=0.0001) and TrueX 5.36%p (P<0.0001), 4.36%p (P<0.0001). Based on the results of the blind test for image resolution and noise from the snapshot, 3D obtained the highest score, followed by 2D, TrueX and FBP. Conclusion: We found that quantitative and semi-quantitative myocardial perfusion values could be under- or over-estimated according to the reconstruction algorithm in $^{13}N-NH_3$ PET/CT. Therefore, proper dynamic and static reconstruction method should be established to provide accurate myocardial perfusion value.

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