• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.3
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• pp.528-534
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• 2007

As XML is becoming a standard for representation and exchange of abundant information on the Web, solutions for a secure and selective dissemination of XML data, known as SDI, are strongly demanded. Such trends are more outstanding especially in distributed heterogeneous environment such as Peer-to-Peer. Although many approaches have been proposed to provide secure and efficient SDI mechanisms, almost previous approaches have focused only on filtering with user profile and they adopt center-oriented administration approaches. It is therefore difficult to adapt them directly to the distributed Peer-to-Peer environments characterized by dynamic participation. In this paper, we develop a novel dissemination method, which makesuse of authorization policy and secret sharing scheme. It provides more secure, scalable means for XML dissemination on Peer-to-Peer networks.

• Proceedings of the Korean Information Science Society Conference
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• 2004.04b
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• pp.172-174
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• 2004

선택적 정보 배포의 의미를 갖는 SDI(Selective Dissemination of Information)서비스는 이용자가 탐색전략을 입력하여 서비스를 신청하면 데이터베이스가 갱신될 때마다 또는 이용자가 지정한 간격으로 자동으로 질의되어 그 결과를 이용자에게 제공하는 서비스로 정의되는데, 이때 대용량의 데이터베이스로부터 복잡한 데이터 질의과정을 거친 데이터가 다수의 사용자들에게 보다 빠르게 전달할 수 있도록 하는 것이 SDI 서비스의 주요한 요구사항이 되고 논다. 본 연구는 다수의 대용량 서비스 데이터베이스를 대상으로 이용자의 요구 주제에 해당하는 정보를 빠르게 서비스하기 위하여 검색시간을 단축할 수 있는 방안으로 'SDI 서비스 전용 데이터베이스'와 '검색결과저장 데이터베이스'를 별도로 두는 시스템을 제시한다. 이를 통해 동일한 질의에 대한 데이터베이스 검색이 최소화되고 검색대상 정보의 범위가 축소되며, 아울러 서비스 대상 데이터베이스의 확장도 용이해진다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.8
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• pp.1505-1510
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• 2008

In large-scale wireless sensor networks, the deployed nodes cannot be replaced or recharged after first deployment. Also, dead nodes maγ lead to the partition of whole networks. While performing data dissemination under a battery power constraint, energy efficiency is a key design factor of routing protocol. As a solution for the efficient data dissemination, in this paper, we propose a protocol namely Hierarchical Data Dissemination (HDD) which provides scalable and efficient data delivery to multiple sources and mobile sinks. HDD uses the facts that sink nodes are central gathering Points and source-centric data forwarding paths are constructed and it is maintained with two-tier communications. The performance of HDD is compared with TTDD about the energy consumption, data delivery time and data success ration. The extensive simulation results show that HDD Routing Protocol outperforms TIDD by more than $1.5{\sim}3times$ on energy consumption.

• Journal of the Korean Data and Information Science Society
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• v.21 no.4
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• pp.783-793
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• 2010

Several multi-hop applications developed for vehicular ad hoc networks use broadcast as a means to either discover nearby neighbors or propagate useful traffic information to other vehicles located within a certain geographical area. However, the conventional broadcast mechanism may lead to the so-called broadcast storm problem, a scenario in which there is a high level of contention and collisions at the link layer due to an excessive number of broadcast packets. We present a fuzzy alert message dissemination algorithm to improve performance for road safety alert application in Vehicular Ad-hoc Network (VANET). In the proposed algorithm, when a vehicle receives an alert message for the first time, the vehicle rebroadcasts the alert message according to the fuzzy control rules for rebroadcast degree, where the rebroadcast degree depends on the current traffic density of the road and the distance between source vehicle and destination vehicle. Also, the proposed algorithm is the hybrid algorithm that uses broadcast protocol together with token protocol according to traffic density. The performance of the proposed algorithm is evaluated through simulation and compared with that of other alert message dissemination algorithms.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.11
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• pp.1431-1439
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• 2016

In this paper, we propose a new location service and location-based routing for data dissemination from a source to a mobile group sink in less energy consumption of the sensor node. Unlike the existing protocols, the proposed protocol uses a leader sink instead of a group area as the location information to represent a mobile sink group. The proposed protocol also uses grid leaders on virtual grid structure to support sink mobility in location service. By using a leader sink as a representative and grid leaders for mobility supporting, the proposed protocol can exploit an efficient hierarchical location service and data dissemination method without using flooding. Accordingly, the proposed protocol carries out upper layer location services and data dissemination between a leader sink and a source and lower layer location services and data dissemination between the leader sink and member sinks. Simulation results demonstrate that the proposed protocol achieves energy-efficiency.

• Korean Journal of Agricultural and Forest Meteorology
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• v.2 no.1
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• pp.24-30
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• 2000

This paper is to introduce distinctive trends in Agrometeorological Information(AgMI) these days, as well as newly emerging technologies from advanced sciences that are promising to enhance production and dissemination of AgMI in the future. The basic concept and important characteristics of AgMI were described either in general or in technical terms. Then AgMI was rather arbitrarily classified here into several groups, simply to show the diversity of AgMI resources available and technologies employed. The production, management, dissemination and communication of AgMI are envisaged to some extent together with the introduction of current status of AgMI production in Korea. Finally a couple of personal prospects on AgMI for agricultural applications are listed in terms of applicable subjects in Agricultural activities, current practicing cases in Korea and future perspectives for sustainable agriculture.

• The KIPS Transactions:PartC
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• v.16C no.4
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• pp.423-438
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• 2009

The sensor network is highlighted because it is one of the essentialbase networks in the ubiquitous computing realization. Researches for providing security and efficiency are being perfomed in the various isuues because of the characteristics of sensor nodes and sensor networks. Recently, code dissemination mechanism is recognized as an important research issue since sensor nodes are in the need of updating new software or the need of modifying bugs in dynamically. Generally lots of nodes are in the sensor networks and they are ramdomly deployed in hostile environments. Thus it is especially important that the code dissemination from the base station to nodes should be processed efficienctly and securely. In this paper, we check up the recent existing code dissemination mechanisms, and comparatively analyze the requirements of the code dissemination and the characteristicsof existing mechanisms. Through the analysis, we present future research issues for the code dissemination area. This research can expedite the research on the code dissemination and improve the usability of sensor networks with efficiency and security.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.3
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• pp.815-834
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• 2012

Recently, along with the innovative development of wireless communication techniques and mobile devices, mobile P2P services in mobile wireless networks have gained a lot of attention. In this paper, we propose a resource discovery scheme with data dissemination over mobile P2P networks. In the proposed scheme, each peer manages a local information table, a resource index table, and a routing table in a local database to enhance the accuracy and cost of resource discovery. The local information table stores the status of a mobile peer, and the resource index table stores the resource information of the neighbor peers via the ranking function. The routing table is used to communicate with the neighbor peers. We use a timestamp message to determine whether or not the resource index table will be changed before the resource information is exchanged. Our ranking function considers the interest and mobility of the mobile peer and prioritizes the resource information transmitted from the neighbor peers. It is shown via various experiments that the proposed scheme outperforms the existing scheme.

• Journal of the Korea Safety Management & Science
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• v.13 no.2
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• pp.31-42
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• 2011

Smart-Phones are utilized in disaster management field because it can deliver disaster information to large population simultaneously and quickly, and provide accurate information through situation-based service using the LBS(Location Based Service). To study on the utilization of smart phone for disaster information collection and dissemination method, this study suggest a framework which connects smart phone by loading application for reporting disaster. The disaster monitoring and situation dissemination system framework using smart phone is composed of 4 parts. First, smart phone application enters image, video, voice and text information and location of the disaster. Second, the disaster report reception and situation dissemination server receives the information, save in the DB, and send through smart phone SMS. Third, store into disaster information database. Fourth, display the disaster report and management information on 2D GIS, support the decision making process in deciding whether to manage as disaster, and disaster management web service which disseminates situation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.4
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• pp.721-727
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• 2016

In this paper, in order to resolve the problem of reduction for D2D (device to device) advertisement dissemination efficiency of conventional dissemination algorithms, we here propose several clustering algorithms (modified single linkage algorithm (MSL), K-means algorithm, and expectation maximization algorithm with Gaussian mixture model (EM)) based advertisement dissemination algorithms to improve advertisement dissemination efficiency in D2D communication networks. Target areas are clustered in several target groups by the proposed clustering algorithms. Then, D2D advertisements are consecutively distributed by using a routing algorithm based on the geographical distribution of the target areas and a relay selection algorithm based on the distance between D2D sender and D2D receiver. Via intensive MATLAB simulations, we analyze the performance excellency of the proposed algorithms with respect to maximum number of relay transmissions and D2D user density ratio in a target area and a non-target area.