• Title/Summary/Keyword: Open network

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Protection Management for Guaranteed User-Driven Virtual Circuit Services in Dynamic Multi-domain Environments: Design Issues and Challenges

  • Lim, Huhnkuk
    • ETRI Journal
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    • v.37 no.2
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    • pp.369-379
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    • 2015
  • Fault management of virtualized network environments using user-driven network provisioning systems (NPSs) is crucial for guaranteeing seamless virtual network services irrespective of physical infrastructure impairment. The network service interface (NSI) of the Open Grid Forum reflects the need for a common standard management API for the reservation and provisioning of user-driven virtual circuits (VCs) across global networks. NSI-based NPSs (that is, network service agents) can be used to compose user-driven VCs for mission-critical applications in a dynamic multi-domain. In this article, we first attempt to outline the design issues and challenges faced when attempting to provide mission-critical applications using dynamic VCs with a protection that is both user-driven and trustworthy in a dynamic multi-domain environment, to motivate work in this area of research. We also survey representative works that address inter-domain VC protection and qualitatively evaluate them and current NSI against the issues and challenges.

An Analysis of a Multilayered Open Queueing Network with Population Constraint and Constraint and Constant Service Times (사용자수 제한을 갖는 개방형 다중계층구조의 대기행렬 네트워크 분석에 관한 연구)

  • Lee, Yeong
    • Journal of the Korean Operations Research and Management Science Society
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    • v.24 no.4
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    • pp.111-122
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    • 1999
  • In this paper, we consider a queueing network model. where the population constraint within each subnetwork is controlled by a semaphore queue. The total number of customers that may be present in the subnetwork can not exceed a given value. Each node has a constant service time and the arrival process to the queueing network is an arbitrary distribution. A major characteristics of this model is that the lower layer flow is halted by the state of higher layer. We present some properties that the inter-change of nodes does not make any difference to customer's waiting time in the queueing network under a certain condition. The queueing network can be transformed into a simplified queueing network. A dramatic simplification of the queueing network is shown. It is interesting to see how the simplification developed for sliding window flow control, can be applied to multi-layered queueing network.

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DIMPLE-II: Dynamic Membership Protocol for Epidemic Protocols

  • Sun, Jin;Choi, Byung-K.;Jung, Kwang-Mo
    • Journal of Computing Science and Engineering
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    • v.2 no.3
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    • pp.249-273
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    • 2008
  • Epidemic protocols have two fundamental assumptions. One is the availability of a mechanism that provides each node with a set of log(N) (fanout) nodes to gossip with at each cycle. The other is that the network size N is known to all member nodes. While it may be trivial to support these assumptions in small systems, it is a challenge to realize them in large open dynamic systems, such as peer-to-peer (P2P) systems. Technically, since the most fundamental parameter of epidemic protocols is log(N), without knowing the system size, the protocols will be limited. Further, since the network churn, frequently observed in P2P systems, causes rapid membership changes, providing a different set of log(N) at each cycle is a difficult problem. In order to support the assumptions, the fanout nodes should be selected randomly and uniformly from the entire membership. This paper investigates one possible solution which addresses both problems; providing at each cycle a different set of log(N) nodes selected randomly and uniformly from the entire network under churn, and estimating the dynamic network size in the number of nodes. This solution improves the previously developed distributed algorithm called Shuffle to deal with churn, and utilizes the Shuffle infrastructure to estimate the dynamic network size. The effectiveness of the proposed solution is evaluated by simulation. According to the simulation results, the proposed algorithms successfully handle network churn in providing random log(N0 fanout nodes, and practically and accurately estimate the network size. Overall, this work provides insights in designing epidemic protocols for large scale open dynamic systems, where the protocols behave autonomically.

A Distance Approach for Open Information Extraction Based on Word Vector

  • Liu, Peiqian;Wang, Xiaojie
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.6
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    • pp.2470-2491
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    • 2018
  • Web-scale open information extraction (Open IE) plays an important role in NLP tasks like acquiring common-sense knowledge, learning selectional preferences and automatic text understanding. A large number of Open IE approaches have been proposed in the last decade, and the majority of these approaches are based on supervised learning or dependency parsing. In this paper, we present a novel method for web scale open information extraction, which employs cosine distance based on Google word vector as the confidence score of the extraction. The proposed method is a purely unsupervised learning algorithm without requiring any hand-labeled training data or dependency parse features. We also present the mathematically rigorous proof for the new method with Bayes Inference and Artificial Neural Network theory. It turns out that the proposed algorithm is equivalent to Maximum Likelihood Estimation of the joint probability distribution over the elements of the candidate extraction. The proof itself also theoretically suggests a typical usage of word vector for other NLP tasks. Experiments show that the distance-based method leads to further improvements over the newly presented Open IE systems on three benchmark datasets, in terms of effectiveness and efficiency.

Analysis of Open Toll Segments in Urban Freeways (개방식고속도로 통행특성과 영업체계 전환분석)

  • Nam, Du-Hui
    • Journal of Korean Society of Transportation
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    • v.25 no.5
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    • pp.101-109
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    • 2007
  • Two variations of toll roads exist: mainline toll plazas and entry/exit tolls. On a mainline toll system(open toll scheme), all vehicles stop at various locations along the highway to pay a toll. While this may save money from the lack of need to construct tolls at every exit, it can cause lots of traffic congestion, and drivers could evade tolls by going around them. With entry/exit tolls, vehicles collect a ticket when entering the highway, which displays the fares it will pay when it exits, increasing in cost for distance travelled. Upon exit, the driver will pay the amount listed for the given exit. The pressures on the Seoul ring roadway network have been changing over time. In the past, the emphasis was on mobility and maintenance of the road network to provide an efficient transportation network, but recently, road use has outstripped the network's ability to extend and expand the road network and hence the policy emphasis has moved towards reducing free riders rather than mitigating its effects. In addition to this pressure is an incidental pressure, which argues that provision of free ride segments generates further traffic in isolation of other factors. This paper is examining policies to reduce the burden of traffic congestion in Seoul ring roadway which is used open toll scheme for decades. One key mechanism to achieve this policy aim is automatic charging mechanism on freeway, but if a nation-wide electronic toll collection is to be implemented successfully, there are a number of prerequisites which must be place.

An IMS based Architecture Using SDN Controller (SDN 제어기를 사용한 IMS 기반 구조)

  • Liu, Zeqi;Lee, Jae-Oh
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.8
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    • pp.19-24
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    • 2018
  • The IP Multimedia Subsystem(IMS) is an architectural framework for delivering IP multimedia services to mobile users. In order to guarantee the reliability and Quality of Service(QoS) of a variety of multimedia services, we need a new evolutionary approach that maintains the IMS based signaling platform which can perform the processing of flow through distributed controllers. Software Defined Network(SDN) is an architecture purporting to be distributed, dynamic, cost-effectives as well as adapting and seeking to be suitable for the high-bandwidth, dynamic nature of today's applications. It requires some methods for the control plane to communication with the data plane. One of such mechanisms is OpenFlow which is a prominent standard protocol and interface that is responsible for managing the network resources by using the remote SDN controller. In this paper, we propose a straightforward approach for integrating SDN technology together with the IMS architecture. Therefore we propose and construct a combined architecture model that performs flow processing using OpenFlow via the IMS based signaling platform, which maintains the existing telecom call service. Additionally, we describe some relevant experimentation results from the proposed architecture.

Development of the Bibliographic Information Network Prototype for Biology and Life Science (생명과학 문헌정보 네트워크 프로토타입 개발)

  • Ahn, Bu-Young;Song, Chi-Pyoung
    • Journal of Information Management
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    • v.36 no.2
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    • pp.125-151
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    • 2005
  • The eight types of Korean bibliographic information of biology and life science are included in PubMed that serves universal medical bibliographic information. Other domestic bibliographic information are served on its own format at different organizations. To fulfill the CCBB homepage user's request that it is necessary that integration of bibliographic service for quick acquisition of research information, we intends to construct metadata registry and service about bibliographic information of biology and life science. This paper describes the design and implementation of bibliographic information network prototype for biology and life science that can be used to share latest research result, seminar presentation data, research note, and research paper etc as well as to exchange information between researchers through Open Archiving Community.

A Parasitic Elements Extraction of MIM Capacitor Using Short-Open Calibration Method (단락 개방 Calibration 방법을 이용한 MIM 커패시터의 기생 소자 값 추출)

  • Kim, Yu-Seon;Nam, Hun;Lim, Yeong-Seog
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.45 no.8
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    • pp.114-120
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    • 2008
  • In this paper, we extract the parasitic elements of the metal-insulate-metal(MIM) capacitor using short-open calibration (SOC). The scattering matrixes of short, open, and MIM structures in strip lines are measured by full electro-magnetic (EM) simulator and vector network analyser. The full EM simulations are performed by finite element method (FEM) that was fitted three dimensional structure analysis. The electro-magnetic effects of MIM capacitor laminated in the multi-layered structures are proposed the II equivalent circuit with lumped elements, and the relations between the measured scattering parameters of the MIM structures and lumped elements in the circuits are shown by performing 2 port network analysis. The extracted lumped elements using the proposed SOC method are independent to frequencies.

SNA Pattern Analysis on the Public Software Industry based on Open API Big Data from Korea Public Procurement Service (조달청 OPEN API 빅데이터를 활용한 공공 소프트웨어 산업의 SNA 패턴 분석)

  • KIM, Sojung lucia;Shim, Seon-Young;Seo, Yong-Won
    • Informatization Policy
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    • v.24 no.3
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    • pp.42-66
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    • 2017
  • This study investigated the ecological change of public software industry, comparing the pre and post structure of industry network based on the application of the regulation restricting large company participation in public software market. For this purpose, we used big data of the software market from Korea Public Procurement Service and used the SNA(Social Network Analysis) methodology which is being actively used in the area of social science recently. Finally, we highlighted the contribution of open public data. By analyzing order and contract data of the public software industry for 3 years - from 2013 to 2015 - we found out two main things. First, we observed that Power Law distribution had been going on in the public software industry, regardless of the external impact of regulation. Second, despite the existence of such Power Law distribution, we also observed the ecological change of industry structure from year to year. We presented the implication of such findings and discussed the advantage of open public data as the original motivator of this study.

Volume Control using Gesture Recognition System

  • Shreyansh Gupta;Samyak Barnwal
    • International Journal of Computer Science & Network Security
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    • v.24 no.6
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    • pp.161-170
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    • 2024
  • With the technological advances, the humans have made so much progress in the ease of living and now incorporating the use of sight, motion, sound, speech etc. for various application and software controls. In this paper, we have explored the project in which gestures plays a very significant role in the project. The topic of gesture control which has been researched a lot and is just getting evolved every day. We see the usage of computer vision in this project. The main objective that we achieved in this project is controlling the computer settings with hand gestures using computer vision. In this project we are creating a module which acts a volume controlling program in which we use hand gestures to control the computer system volume. We have included the use of OpenCV. This module is used in the implementation of hand gestures in computer controls. The module in execution uses the web camera of the computer to record the images or videos and then processes them to find the needed information and then based on the input, performs the action on the volume settings if that computer. The program has the functionality of increasing and decreasing the volume of the computer. The setup needed for the program execution is a web camera to record the input images and videos which will be given by the user. The program will perform gesture recognition with the help of OpenCV and python and its libraries and them it will recognize or identify the specified human gestures and use them to perform or carry out the changes in the device setting. The objective is to adjust the volume of a computer device without the need for physical interaction using a mouse or keyboard. OpenCV, a widely utilized tool for image processing and computer vision applications in this domain, enjoys extensive popularity. The OpenCV community consists of over 47,000 individuals, and as of a survey conducted in 2020, the estimated number of downloads exceeds 18 million.