• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2000년도 가을 학술발표논문집 Vol.27 No.2 (1)
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• pp.48-50
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• 2000

최근 텍스트, 이미지, 오디오, 비디오와 같은 멀티미디어 객체를 다루는 연구는 국내외적으로 활발하게 진행되고 있으나, 이러한 멀티미디어 객체들을 효율적으로 저장 및 검색하기 위한 하부저장 시스템에 대한 연구는 미흡한 실정이다. 본 연구에서는 이러한 대용량 멀티미디어 객체들을 효율적으로 저장 및 검색하기 위한 구조를 분석하고 다양한 이질적 객체들을 위한 객체 관리자 및 대용량 텍스트를 위한 역화일 관리자를 설계한다. 아울러, 기존의 하부저정 구조인 SHORE 저장시스템에 통합하여 DBMS 측면에서 제공하는 동시성 제어, 회복기법 등을 지원할 수 있는 객체저장 엔진을 구현한다.

• 한국GIS학회:학술대회논문집
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• 한국GIS학회 1996년도 춘계학술대회 발표요약문
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• pp.63-77
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• 1996

본 연구에서는 지리 정보 시스템(GIS: geographic information system)에서 주로 사용되는 공간 객체를 위한 색인 방법에 대해서 과거의 연구를 토대로 분류를 해보고 이로부터 새로이 제안하는 색인 방법인 MAX (Multi-Attribute indexing scheme)에 대해서 상세히 기술한다. 또한 MAX의 여러 연산을 위한 알고리즘을 제시하고, 알고리즘의 우수성을 제시한다. 이미 성능 평가를 통해 어느 정도의 성능을 기대할 수 있으며, 이를 실제 시스템에 구현한다면 상당한 성능을 가진 지리 정보 시스템을 구축할 수 있을 것이다. 특히 MAX는 이 기법이 가지는 B 트리의 확장성으로 쉽게 구현할 수 있는 구조를 가지게 된다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.597-599
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• 2003

Moving pattern is as a kind of sequential pattern, which can be extracted from the large volume of location history data. This sort of knowledge is very useful in supporting intelligence to the LBS or GIS. In this paper, we proposed the continuous moving pattern mining approach in LBS platform and LBS Miner. The location updates of moving objects affect the set of the rules maintained. In our approach, we use the validity thresholds that indicate the next time to invoke the incremental pattern mining. The mining system will play a major role in supporting the various LBS solutions.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2002년도 가을 학술발표논문집 Vol.29 No.2 (1)
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• pp.49-51
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• 2002

대용량 이동 객체의 경우에 특정 객체의 이동경로를 추적유지 해야할 필요성이 있으며 효과적으로 검색하기 위한 인덱스가 필요하다. 본 논문에서는 이동 객체의 위치 정보를 위한 데이터 구조를 제시하고 저장된 데이타를 효과적으로 처리하기 위한 인덱스 구성방안을 제안한다. 인덱스 구조는 대량의 객체의 동시 이동으로 인한 갱신 오버헤드를 최소화할 수 있도륵 한다. 이 시스템은 이동 통신 분야에서 고객 위치 정보를 필요로 하는 다양한 서비스와 항공기 운항 제어 등의 분야에서 활용될 수 있다.

• International Journal of Contents
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• 제7권4호
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• pp.1-5
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• 2011

Physics based fluid animation schemes need large computation cost due to tremendous degree of freedom. Many researchers tried to reduce the cost for solving the large linear system that is involved in grid-based schemes. GPU based algorithms and advanced numerical analysis methods are used to efficiently solve the system. Other groups studied local operation methods such as SPH (Smoothed Particle Hydrodynamics) and LBM (Lattice Boltzmann Method) for enhancing the efficiency. Our method investigates this efficiency problem thoroughly, and suggests novel paradigm in fluid animation field. Rather than physics based simulation, we propose a robust boundary handling technique for procedural fluid animation. Our method can be applied to arbitrary shaped objects and potential fields. Since only local operations are involved in our method, parallel computing can be easily implemented.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2005년도 추계종합학술대회
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• pp.557-560
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• 2005

The color of objects varies with changes in illuminant color and viewing conditions. As a consequence, color boundaries are influenced by a large variety of imaging variables such as shadows, highlights, illumination, and material changes. Therefore, invariant color models are useful for a large number of applications such as object recognitions, detections, and segmentations. In this paper, we propose invariant color models. These color models are independent of the object geometry, object pose, and illumination. From these color models, color invariant edges are derived. To show the validity of the proposed invariant color models, some examples are given.

• Journal of international Conference on Electrical Machines and Systems
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• 제2권4호
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• pp.380-389
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• 2013

Application of linear electric motors to automation of manufacturing processes, gantry robots, machining processes, machining centers, additive manufacturing and laser scribing has been discussed. The paper focuses on replacement of ball lead screw mechanisms with linear electric motors, linear motor driven positioning stages, linear motor driven gantries, machining centers, machining of large objects and industrial lasers. The best linear electric motors for application to machining processes are permanent magnet (PM) linear synchronous motors (LSMs), especially those without PMs in the reaction tail, e.g., high thrust density linear (HDL) LSMs and PM flux switching (FS) LSMs.

• 천문학회보
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• 제40권2호
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• pp.50.4-51
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• 2015

Current and planned deep multicolor wide-area cosmological surveys will map in detail the spatial distribution of galaxies and quasars over unprecedented volumes, and provide a number of objects with photometric redshifts more than an order of magnitude bigger than that of spectroscopic redshifts. Photometric information is statistically more significant for studying cosmological evolution, dark energy, and the expansion history of the universe at a fraction of the cost of a full spectroscopic survey, but intrinsically carries a bias due to noise in the distance estimates. We provide convolution- and deconvolution-based algorithms capable of removing this bias -- thus able to exploit the full cosmological information -- in order to reconstruct intrinsic distributions and correlations between distance-dependent quantities. We then show some direct applications of our techniques to the VIMOS Public Extragalactic Redshift Survey (VIPERS) and the Sloan Digital Sky Survey (SDSS) datasets. Our methods impact a broader range of studies, when at least one distance-dependent quantity is involved; hence, they will be useful for upcoming large-volume surveys, some of which will only have photometric information.

• 천문학논총
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• 제32권1호
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• pp.123-125
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• 2017

We present our AKARI study of massive star forming regions where a large-scale cloud-cloud collision possibly contributes to massive star formation. Our targets are Spitzer bubbles, which consist of two types of bubbles, closed and broken ones; the latter is a candidate of the objects created by cloud-cloud collisions. We performed mid- and far-infrared surface photometry toward Spitzer bubbles to obtain the relationship between the total infrared luminosity, $L_{IR}$, and the bubble radius, R. As a result, we find that $L_{IR}$ is roughly proportional to $R^{\beta}$ where ${\beta}=2.1{\pm}0.4$. Broken bubbles tend to have larger radii than closed bubbles for the same $L_{IR}$.

• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 1999년도 추계공동학술대회 논문집:21세기지식경영과 정보기술
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• pp.769-781
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• 1999

Manufacturing systems are usually large, complex, and concurrent in nature that makes it difficult to model and simulate the behavior in advance. The paper proposes an approach, called OPNets, for modeling and validating manufacturing systems. The approach is based on object-oriented high-level Petri nets in which modeling components of Petri net are constructed into object hierarchy. The objects communicate with each other by passing messages. To enhance the reusability and maintainability, a system are developed by object hierarchy. Inheritance among object hierarchy is also supported in OPNets. The modeling scheme of OPNets tries to resolve the complexity problems of Petri net.