• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.696-701
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• 2002

This paper describes some results of change detection in Tokyo metropolitan area, Japan , using the Landsat TM data, and methods to quantify the ground cover classes. The changes are analyzed using the measures of not only conventional spectral classes but also a set of landscape indices to describe spatial properties of ground cove types using fractal dimension of objects, entropy in the specific windows defining the neighbors of focusing locations. In order eliminate the seasonal radiometric effects on TM data, an automated class labeling method is also attempted. Urban areas are also delineated automatically by defining the boundaries of the urban area. These procedures for urban change detection were implemented by the unified image computing methods proposed by the author, they can be automated in coherent and systematic ways, and it is anticipated to automate the whole procedures. The results of this analysis suggest that Tokyo metropolitan area was extended to the suburban areas along the new transportation networks and the high density area of Tokyo were also very much extended during the period between 1985 and 1995.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.309-312
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• 2005

The need for LBS (Loc,ation Based Services) is increasing due to the wnespread of mobile computing devices and positioning technologies~ In LBS, there are many applications that need to manage moving objects (e.g. taxies, persons). The moving object join operation is to make pairs with spatio-temporal attribute for two sets in the moving object database system. It is import and complicated operation. And processing time increases by geometric progression with numbers of moving objects. Therefore efficient methods of spatio-temporal join is essential to moving object database system. In this paper, we apply spatial join methods to moving objects join. We propose two kind of join methods with TB- Tree that preserves trajectories of moving objects. One is depth first traversal spatio-temporaljoin and another is breadth-first traversal spatio-temporal join. We show results of performance test with sample data sets which are created by moving object ,generator tool.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.778-784
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• 2005

Miniaturization of computing devices, and advances in wireless communication and positioning systems will create a wide and increasing range of database applications such as location-based services, tracking and transportation systems that has to deal with Moving Objects. Various types of queries could be posted to moving objects, including past, present and future queries. The key problem is how to model the location of moving objects and enable Database Management System (DBMS) to predict the future location of a moving object. It is obvious that there is a need for an innovative, generic, conceptually clean and application-independent approach for spatio-temporal handling data. This paper presents behavioral aspect of the spatio-temporal databases for managing and querying moving objects. Our objective is to impelement and extend the Spatial TAU (STAU) system developed by Dr.Pelekis that provides spatio-temporal functionality to an Object-Relational Database Management System to support modeling and querying moving objecs. The results of the impelementation are demonstrated in this paper.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제16권12호
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• pp.1209-1213
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• 2010

최근 모바일 장치의 기능이 발전하면서, 스마트폰에 대한 관심이 증가하고 있다. 스마트폰은 휴대성이라는 장점을 가지고 있음에도 불구하고, 그 기기의 크기가 작아 사용자 인터페이스 관점에서 불편함이 많이 있었다. 본 논문에서는 이 문제점올 해결하기 위해 안드로이드 모바일 플랫폼에서의 프레임버퍼 구조를 수정하여, 동적으로 해상 전환시켜 크기가 큰 외부 디스플레이 장치로 디스플레이를 전환하고, 기존의 휴대폰은 리모콘으로 활용할 수 있는 사용자 인터페이스 전환 기술을 개발하였다.

• 한국전자거래학회지
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• 제8권1호
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• pp.141-154
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• 2003

SOAP is a protocol used for information exchange in distributed computing environment and SOAP defines mechanisms for message transferring between distributed system and remote procedure call/response process. This SOAP is able to be used independently on hardware platforms and operating systems and program languages because it uses only a text-based XML for protocol. Therefore ebXML that is a standard for E-Commerce adopts SOAP for message exchange. In this paper, we implement XML Hub System using SOAP and apply on the system e-Procurement. By this XML Hub System we can more easily exchange messages for B2B. Accordingly we can manage and integrate a lots of business partners.

• 인터넷정보학회논문지
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• 제6권3호
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• pp.31-43
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• 2005

OTAR시스템은 높은 보증 등급의 키 관리 기능을 구현한 것이며, 접근 통제, 무결성, 기밀성 기능을 확신할 수 있는 무선을 통한 원격 키 갱신 기술을 갖는다. 하지만 TIA/EIA OTAR 기술은 현실적인 측면에서 안전성의 개선이 요구된다. 본 논문에 서는 무선 정보보안시스템에 적용 가능한 무선을 통한 키 갱신 기술인 TIA/EIA OTAR에 대한 보안 취약점을 분석한 후, 취약점을 수정 보완한 개선된 OTAR 보안 시스템을 제안한다. 제안 시스템에는 신뢰성이 높은 난수 동기방식을 포함한다.

• Journal of Computing Science and Engineering
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• 제7권4호
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• pp.272-284
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• 2013

In this paper, we propose a new framework for anomaly detection in medical wireless sensor networks, which are used for remote monitoring of patient vital signs. The proposed framework performs sequential data analysis on a mini gateway used as a base station to detect abnormal changes and to cope with unreliable measurements in collected data without prior knowledge of anomalous events or normal data patterns. The proposed approach is based on the Mahalanobis distance for spatial analysis, and a kernel density estimator for the identification of abnormal temporal patterns. Our main objective is to distinguish between faulty measurements and clinical emergencies in order to reduce false alarms triggered by faulty measurements or ill-behaved sensors. Our experimental results on both real and synthetic medical datasets show that the proposed approach can achieve good detection accuracy with a low false alarm rate (less than 5.5%).

• 한국정보과학회논문지:정보통신
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• 제28권4호
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• pp.570-577
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• 2001

이동 네트워크 상에서의 인터넷 서비스가 활성화됨에 따라 이동 호스트에 대한 인증 및 비밀성이 요구되었고, 이동 호스트의 이동성에 따른 익명성 및 불추적성이 중요한 고려사항이 되었다. 본 논문에서는 이동 호스트가 도메인간을 이동하면서 노출될 수 있는 이동 호스트의 Identity의 보호를 위해 사용자 Alias를 사용하였으며, 원격 도메인에도 Alias를 사용함으로 익명성 보장 및 불추적성을 지원한 안전한 인증 프로토콜을 제시한다. 본 논문에서는 안전성을 높이기 위해서 Alias 생성시 공개키 암호 시스템을 이용하였다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.95-98
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• 2004

In this paper, we propose policy-based authentication framework which consists of policy server, CA and a policy language designed for ubiquitous environments. Using policies allows the security functionality to be modified without changing the implementation of the entities involved. Policy-based authentication framework needs to be very expressive but lightweight and easily extensible. We propose the feasibility of our policy language and policy-based authentication framework in ubiquitous-environment through a prototype and solve the problem that traditional framework have a simple registration and authentication to provide dynamic service.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.283-286
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• 2004

This paper refers and implements XML Web services, which supports networked interchanges of moving object information. XML Web services are expected to be fundamental building blocks in the move to distributed computing on the Internet. As an interchange format, GML encodes semantics, syntax, and schema of geospatial and geoprocessing-related information resources. It can give great benefits to utilize raw data easily as an XML encoding format does. This paper proposes a full coverage of interoperable location trajectory services consisting of 3 independent modules: a moving object database, a data processing server, and a web services interface module. For communications, SOAP protocols and WSDL documents are used, which can guarantee an interoperability of a system regardless of different platforms and service channels. This paper also designs a GML data format that represents location information of probe cars.