• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.18-18
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• 2004

지도작성은 이동로봇의 주행 및 위치추정을 위해 반드시 필요한 요소이다. 이러한 지도작성에는 격자지도와 토폴로지컬 지도의 두 종류가 있다. 격자지도는 전체 환경을 작은 격자로 나누어 각각에 점유되어 있는 확률간을 부여함으로써 지도상의 모든 메트릭(metric) 정보를 나타내는 반면에, 토폴로지컬 지도는 메트릭 정보를 가짐으로써 위치추정을 가능하게 하는 노드와 이를 연결하는 에지로 표현된다.(중략)

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.10a
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• pp.337-338
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• 2009

• Journal of KIISE:Software and Applications
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• v.37 no.7
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• pp.584-589
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• 2010

The dynamic time warping algorithm generally used in time series pattern recognition spends most of the time in generating the correlation table, and it establishes the global path constraint to reduce the corresponding time complexity. However, the constraint restrains just in terms of the time axis, not considering the contents of input patterns. In this paper, we therefore propose an efficient branch and bound dynamic time warping algorithm which sets the global constraints by adaptively reflecting the patterns. The experimental results show that the proposed method outperforms conventional methods in terms of the speed and accuracy.

• Journal of the Korea Society of Computer and Information
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• v.15 no.11
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• pp.11-20
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• 2010

XML view is proposed to integrate between XML data and heterogeneous data over distributed environment and global XML view is used to search distributed heterogeneous data. At this time, standard query language for user is XQuery and the method for processing global XQuery queries over distributed environment is one of the new research topics. One of the basic and simple methods to process distributed SQL queries is that generates local queries for processing a global query and constructs the result of the global query from the results of the local queries. However, the syntax of XQuery differs from SQL because the XQuery contains some special expressions like FOR clauses for querying to semi-structured data, of course, FOR clauses are not used in SQL. Therefore, there are some problems to adopt the method for processing global SQL queries for generating local XQuery queries. This paper defines some problems when generates local XQuery queries for processing global XQuery queries and proposes a method for generating local XQuery queries considered these problems. Also we implement and evaluate a Global XQuery Processor which uses our method.

• Journal of KIISE:Computing Practices and Letters
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• v.6 no.6
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• pp.555-568
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• 2000

The World Wide Web has become the largest virtual system that is almost universal in scope. In recent research, it has become effective to utilize idle hosts existing in the World Wide Web for running applications that require a substantial amount of computation. This novel computing paradigm has been referred to as the advent of global computing. In this paper, we implement and propose a mobile object-based global computing framework called Tiger, whose primary goal is to present novel object-oriented programming libraries that support distribution, dispatching, migration of objects and concurrency among computational activities. The programming libraries provide programmers with access, location and migration transparency for distributed and mobile objects. Tiger's second goal is to provide a system supporting requisites for a global computing environment - scalability, resource and location management. The Tiger system and the programming libraries provided allow a programmer to easily develop an objectoriented parallel and distributed application using globally extended computing resources. We also present the improvement in performance gained by conducting the experiment with highly intensive computations such as parallel fractal image processing and genetic-neuro-fuzzy algorithms.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.822-827
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• 2003

Topological maps have drawn more attention recently because they are compact, provide natural interfaces, and are applicable to path planning easily. To build a topological map incrementally, Voronoi diagram was used by many researchers. The Voronoi diagram, however, has difficulty in applying to arbitrarily shaped objects and needs long computation time. In this paper, we present a new method for global topological map from the local topological maps incrementally. The local topological maps are created through a thinning algorithm from a local grid map, which is built based on the sensor information at the current robot position. A thinning method requires simpler computation than the Voronoi diagram. Localization based on the topological map is usually difficult, but additional nodes created by the thinning method can improve localization performance. A series of experiments have been conducted using a two-wheeled mobile robot equipped with a laser scanner. It is shown that the proposed scheme can create satisfactory topological maps.

• Annual Conference on Human and Language Technology
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• 2018.10a
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• pp.47-49
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• 2018

최근 존재하는 대부분의 관계 추출 모델은 언급 수준의 관계 추출 모델이다. 이들은 성능은 높지만, 문서에 존재하는 다수의 문장을 처리할 때, 문서 내에 주요 개체 및 여러 문장에 걸쳐서 표현되는 개체간의 관계를 분류하지 못한다. 이는 높은 수준의 관계를 정의하지 못함으로써 올바르게 데이터를 정형화지 못하는 중대한 문제이다. 해당 논문에서는 이러한 문제를 타파하기 위하여 여러 문장에 걸쳐서 개체간의 상호작용 관계도 파악하는 전역 수준의 관계 추출 모델을 제안한다. 제안하는 모델은 전처리 단계에서 문서를 분석하여 사전 지식베이스, 개체 연결 그리고 각 개체의 언급횟수를 파악하고 문서 내의 주요 개체들을 파악한다. 이후 언급 수준의 관계 추출을 통하여 1차적으로 단편적인 관계 추출을 실행하고, 주요개체와 관련된 관계는 외부 메모리에 샘플로 저장한다. 이후 단편적 관계들과 외부메모리를 이용하여 여러 문장에 걸쳐 표현되는 개체 간 관계를 알아낸다. 해당 논문은 이러한 모델의 구조도와 실험방법의 설계에 대하여 설명하였고, 해당 실험의 기대효과 또한 작성하였다.

• Journal of Korean Society of Forest Science
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• v.110 no.3
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• pp.355-368
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• 2021

This study aims to identify appropriate tree species and crops for agroforestry target sites in North Korea based on ecological geography and site properties. To this end, an ecological geographic map (13 regions and 4 zones) of North Korea was made using satellite images and North Korean academic journal articles. The target agroforestry sites were selected and mapped according to 18 site conditions depending on 3 site characteristics, and the sites were divided into short-term and long-term target sites depending on the agroforestry management period. Finally, optimal combinations of 30 tree species and 19 crops were selected by overlapping the ecological geographic map and agroforestry target site map. For regions within the same zone, tree species and crops were almost similar; however, compared to regions in other zones, they differed. This is likely because the geographical climatic characteristics reflected in the ecological geographic map vary greatly from zone to zone. These results will be used to propose a combination of suitable tree species and crops that takes into account both management purposes and management types for inter-Korean forest cooperation in the agroforestry sector.

• The Journal of Engineering Geology
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• v.10 no.2
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• pp.215-233
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• 2000

The national geochemical baseline mapping project has been conducted since 1996 to establish a quantitative assessment system for geochemical hazards in natural environments. The geochemical image maps have been edited for thirty-six elements(i.e., 10 major oxides and 26 trace elements) in light sediments, finer fraction than 150 $\mu$m, collected from first- to second-order streams(totally 11,000) over five provinces in the western half(ca. 45,000 km$^2$) of Korea. Natural background values of the elements were given for different geological environments. Based on the statistics, geochemical baselines were newly obtained for a quantitative hazard assessment on toxicity of heavy metals and deficiency of essential nutrients. Some chosen examples of geochemical hazards are presented based on new geochemical image maps and related baseline data.

• Journal of the Korean Society of Industry Convergence
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• v.13 no.2
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• pp.85-92
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• 2010

This study shows the path generation algorithm for an UGV (Unmanned Ground Vehicle). The developed UGV frame which has a 4-wheel driven mechanism and diesel source is applied. Proposed vehicle system in this research is aimed to military purpose. To achieve the unmanned autonomous driving, following two main issues are considered. First, behavior module for positioning and posture of vehicle system and second, cognition module to receive the information from environment are proposed and verified. To do this, rover which can acquire the positioning information from earth coordinate and IMU (Inertial Measurement Unit) which can measure the posture are combined to design the path planning algorithm.