• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.10a
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• pp.102-105
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• 2010

Traditional Pub/Sub(Publish/Subscribe) Systems search all subscriptions that match an incoming event by broker(i.e. it is not considering the accuracy of matching between an incoming event and subscriptions and only consider that an event either matches a subscription or not). However, subscriptions that match an event may have priority, therefore, we need priority Pub/Sub system. In this paper, we define what the accuracy means in order to prioritize among subscriptions and propose the Priority Retrieval Technique based on accuracy that able to search subscriptions. The Priority Retrieval Technique is based on IS-Lists. We can search the results ordered by accuracy.

• Proceedings of the Korean Information Science Society Conference
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• 2006.10d
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• pp.723-727
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• 2006

애드혹 유비쿼터스 컴퓨팅 환경에서 상호작용 미들웨어는 컨텍스트의 변화에 따라 애플리케이션간의 상호작용을 재구성할 수 있도록 지원해야 한다. 또한 미들웨어는 컨텍스트 인지 상호작용을 지원하는데 있어 컨텍스트 종류나 애플리케이션들 혹은 환경의 다양성에 따라 컨텍스트 변화에 대한 적응성을 동적으로 변화시킬 수 있도록 기능을 제공해야 한다. 하지만 기존 연구들은 컨텍스트 변화에 대한 적응성을 변화시키는 이러한 요소들에 대해 고려하지 않으며 그로 인해 컨텍스트 변화에 대한 적응 정도를 정적으로 설정함으로써 컨텍스트 인지 상호작용을 지원하는데 있어 경우에 따라 오버헤드가 발생하거나 컨텍스트 변화에 빠르게 대응하지 못한다. 따라서 본 연구는 애드혹 유비쿼터스 컴퓨팅 환경에서 동작하는 Publish/Subscribe 기반의 상호작용 미들웨어에서 이벤트 중계의 정확성과 컨텍스트 변화 적응성간의 관계를 기반으로 다양한 컨텍스트 종류나 사용자, 환경에 따라 이벤트 중계의 정확도를 동적으로 조절하는 기법을 제안한다. 그리고 이를 기반으로 이벤트 중계 정보를 동적으로 재구성하여 컨텍스트에 맞춰 효율적으로 컨텍스트 인지 상호작용을 구성할 수 있는 기법을 제안한다. 비교 분석 결과 기존 연구에 비해 컨텍스트 변화에 대한 적응성에서 더 나은 결과를 보여주었다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.4
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• pp.677-684
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• 2008

We propose an grid-based research system that replays the experiment by storing and reusing the previous experiment result data in performing remote experiment from a distance. The proposed system was designed for the real-time hybrid test facility which is being built in Korea Construction Engineering Development(KOCED) Project. To provide users with various data, the experiment result data are maintained by the distributed streaming servers based on the publish/subscribe paradigm. Based on the data characteristics of our project, we compared analyzed the performance of the one-streaming-server case and the distributed-multiple-streaming-server case.

• Journal of Korea Multimedia Society
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• v.25 no.8
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• pp.1075-1084
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• 2022

Internet of Things(IoT) has become a key available technology for efficiently implementing device to device(D2D) services in various domains such as smart home, healthcare, smart city, agriculture, energy, logistics, and transportation. A lightweight publish/subscribe(Pub/Sub) messaging protocol not only establishes data dissemination pattern but also supports connectivity between IoT devices and their applications. Also, a Pub/Sub broker is deployed to facilitate data exchange among IoT devices. A scalable edge-based publish/subscribe (Pub/Sub) broker overlay networks support latency-sensitive IoT applications. In this paper, we design a hypercube grid quorum(HGQ) for distributed Pub/Sub systems based IoT applications. In designing HGQ, the network of hypercube structures suitable for the publish/subscribe model is built in the edge layer, and the proposed HGQ is designed by embedding a mesh overlay network in the hypercube. As their applications, we propose an HGQ-based mechansim for dissemination of the data of sensors or the message/event of IoT devices in IoT environments. The performance of HGQ is evaluated by analytical models. As the results, the latency and load balancing of applications based on the distributed Pub/Sub system using HGQ are improved.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.11
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• pp.2535-2540
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• 2010

In traditional Publish/Subscribe system, the first procedure to deliver event from publisher to subscriber is that publisher publishes publisher's event to broker. Next step is that broker checks simple binary notion of matching : an event either matches a subscription or it does not. Lastly, broker delivers the event matched with subscriptions to the corresponding subscribers. In this system, information delivery has been accomplished in one way only. However, current some applications require two way delivery between subscriber and publisher. Therefore, we initiate an extended Publish/Subscribe system that supports two way delivery. Extended Publish/Subscribe system requires additional functions of delivering subscription to publisher and especially deciding top-n subscriptions using priority because broker might has a number of subscriptions. In this paper, we propose two priority retrieval techniques based on SIF using IS-List with deciding priority among subscriptions and defining SIF(Specific Interval First). The performance measurements show that RSO(resulting set sorting) technique results in better performance in index creation time and ITS&IS(insertion time sorting and inverse search using stack) technique results in better performance in search time.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.11
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• pp.1-11
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• 2009

A content based pub/sub (Publish/subscribe) services at the peer-to-peer network has the requirements about how to distribute contents information of subscriber and to delivery the events efficiently. For satisfying the requirements, a DHT(Distributed Hash Table) based pub/sub overlay networking and tree type topology based network construction using filter technique have been proposed. The DHT based technique is suitable for topic based pub/sub service but it's not good contents based service that has the variable requirements. And also filter based tree topology networking is not efficient at the environment where the user requirements are distributed. In this paper we propose the R-Tree algorithm based pub/sub overlay network construction method. The proposed scheme provides cost effective event delivery method by mapping user requirement to multi-dimension and hierarchical grouping of the requirements. It is verified by simulation at the variable environment of user requirements and events.

• Journal of KIISE:Databases
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• v.33 no.1
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• pp.138-149
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• 2006

As the environment with sensor network and ubiquitous computing is emerged, there are many demands of handling continuous, fast data such as streaming data. As work about streaming data has begun, work about management of streaming data in Publish-Subscribe system is started. The recent emergence of XML as a standard for information exchange on Internet has led to more interest in Publish - Subscribe system. A filtering technique of streaming XML data in the existing Publish- Subscribe system is using some schemes based on automata and YFilter, which is one of filtering techniques, is very popular. YFilter exploits commonality among path queries by sharing the common prefixes of the paths so that they are processed at most one and that is using the top-down approach. However, because partial matching path queries interrupt the common prefix sharing and don't calculate from root, throughput of YFilter decreases. So we use sharing of commonality among path queries with the common postfixes of the paths and use the bottom-up approach instead of the top-down approach. This filtering technique is called as PoSFilter. And we verify this technique through comparing with YFilter about throughput.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.05a
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• pp.1272-1281
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• 2006

RFID 기술을 이용함으로써 얻을 수 있는 많은 장점으로 인하여, 공급망에서 발생하는 실시간 제품 정보를 수집하고 관리하기 위하여 RFID 기술이 도입되고 있다. 기존의 RFID 기반의 공급망 관리 시스템은 제품의 위치에 따른 가시성은 확보할 수 있지만, 제품의 모든 상태에 따른 가시성은 확보하지 못한다는 단점이 있다. 이러한 단점을 해결하기 위해, 본 논문에서는 공급망 상의 제품 이동을 계획하고, 제품이 계획에 따라 이동할 때 발생하는 정보를 실시간으로 모니터링하고 통제할 수 있는 제품 상태 기반의 물류 통제 시스템을 설계하고 개발하였다. 이를 위해 본 연구에서는 첫째, 공급망에서 발생하는 제품 상태의 정의와 상태 변화의 흐름을 state chart로 표현하고, 둘째, 공급망에서의 폐쇄형관리 패러다임을 통한 제품 통제(감시 및 예외처리)를 정의하였으며, 셋째, Temporal data modeling을 통해 RFID 데이터 기반의 Database를 설계하고, 마지막으로, Publish/Subscribe 모델을 통해 효율적인 제품 상태 기반의 물류 통제 시스템 아키텍처를 설계하였다.

• Journal of Korean Library and Information Science Society
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• v.28
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• pp.137-170
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• 1998

The University Press, as a publishing division of the university, is a high quality and low cost scholarly communication system. In contrast to European and American university presses, Korean university presses publish very small amount of books. So the author took a case study of the Pusan National University Press(PNUP). She interviewed with faculty who had published or were going to publish. And then she analyzed why or why not the faculty at the Pusan National University selected PNUP as a publisher. On the basis Of the results, she identified problems of the PNUP and she made an activating program that can be a n.0, pplied to most of Korean university presses. This program involved setting up the mission of the press; a n.0, ppointing a professional to the staff and establishing a fund; encouraging high quality scholarly publishing, refined bookmaking and positive marketing; and increasing the expense of the library and improving community su n.0, pport of the university press.

• Journal of Korea Multimedia Society
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• v.9 no.6
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• pp.720-727
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• 2006

In this paper, we propose a method which allows the SuperSQL query processor to share as much code as possible among various, generators, each of which is responsible for the output of a certain medium. SuperSQL is an enhanced query-processing system that converts database records into a variety of formats such as XML, HTML, PDF and etc. However, the existing SuperSQL media generator would require creation of a different processor for each medium, causing duplicated development cost. This research makes three main contributions: First, it analyzes the structures of various media, examining any possibility of integration based on their common structure. Second, it also facilitates the addition of a new output media generator by separating constructors and decorators from each medium. Last, it provides an integrated user interface to each media by method of the Media Abstraction Table Concept. We also show the performance and feasibility of our system using experimental results.