• 한국전산유체공학회:학술대회논문집
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• 2005.10a
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• pp.163-167
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• 2005

A research to evaluate efficiency of design optimization was performed for aerodynamic design optimization problem in distributed computing environment. The aerodynamic analyses which take most of computational work during design optimization were divided into several jobs and allocated to associated PC clients through network. This is not a parallel process based on domain decomposition rather than a simultaneous distributed-analyses process using network-distributed computers. GBOM(gradient-based optimization method), SAO(Sequential Approximate Optimization) and RSM(Response Surface Method) were implemented to perform design optimization of transonic airfoil and to evaluate their efficiencies. One dimensional minimization followed by direction search involved in the GBOM was found an obstacle against improving efficiency of the design process in distributed computing environment. The SAO was found quite suitable for the distributed computing environment even it has a handicap of local search. The RSM is apparently the fittest for distributed computing environment, but additional trial and error works needed to enhance the reliability of the approximation model are annoying and time-consuming so that they often impair the automatic capability of design optimization and also deteriorate efficiency from the practical point of view.

• The Journal of Society for e-Business Studies
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• v.12 no.1
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• pp.135-149
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• 2007

There are many kinds of applications or software components to manage files in a local computer, but it is very difficult to organize personal documents in a consistent way and to search expected ones in a precise way. In this paper, we present our development of a document management and retrieval tool, which is named Ontalk. Our system provides a semi-automatic metadata generator and an ontology-based search engine for electronic documents. Ontalk can create and import various ontologies in RDFS or OWL for describing the metadata. Our system that is built upon.NET technology is easily communicated with or flexibly plugged into many different programs.

• The Journal of Society for e-Business Studies
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• v.14 no.4
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• pp.195-214
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• 2009

Semantic web portal is expected to overcome the shortcomings of the current web portals through advanced semantic web technologies and to be an effective and efficient method of knowledge sharing. In order to contribute to the knowledge sharing, semantic web portal needs to construct and integrate ontologies of each organization. Also, it needs to support search and navigation of inter-related knowledge. In this paper, we will design a semantic web portal that satisfies such requirements in the domain of display industry, and construct an ontology which links various knowledge of different fields. Moreover, we want to suggest an effective and automatic search/navigation method that supports customers who do not know the details of an ontology to easily get the desired results.

• Proceedings of the Korea Contents Association Conference
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• 2004.05a
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• pp.377-384
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• 2004

The field based morphing requires the user to set most of the control lines manually which requires much time and skill to get satisfactory results. This thesis proposes a method to acquire semi-automation of image morphing through first acquiring shape information from the source image and the target image, then after the user manually designates the least amount of a pair of feature points, these are used as standards for polygon based vertex search to set the appropriate control line to the source mage and target image, and then using the ratio of control line lengths and space. Using the proposed method, the user can reduce the time setting the control line and unskilled persons can get natural image morphing results while designating the least amount control line.

• Proceedings of the Korea Contents Association Conference
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• 2005.11a
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• pp.66-71
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• 2005

Using for the internet information is easy or difficult. The effort to obtain the useful information is developed the various technique such as search as well as the information repository, classification, processing and the utilization. Specially, such developments are remarkable to the Agent of various uses and the classification, conversion in processing techniques. The study introduces the classification service system of internet documents which is processing from the repository of internet information to the automatic classification and search service.

• Proceedings of the Korea Water Resources Association Conference
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• 1991.07a
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• pp.88-101
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• 1991

충주댐 및 소양강댐 유역에 대해 현재 한국수자원공사에서 개발 사용되고 있는 저류함수 유출모형에 최적화 기법을 적용하여 모형을 효율적으로 자동보정 하기위함이 본 연구의 목적이다. 최적화 기법으로는 다양한 조건하에서도 해의 안정성이 Gradient-Based 방법보다 우수한 직접 탐색법(Direct Search Method)의 하나인 Pattern-Search법으로 선정하였으며 목적함수로는 산정된 유출과 관측치의 편차의 제곱에 대한 누계치로 정의하였다. 합성유입량(Synthetic Inflow)을 이용한 민감도 분석에 의해 매개변수 5개(유역 저류상수 및 지체시간, 포화우량, 하도의 지체시간)를 결정변수로 선정하였다. 또한 실시간 모형의 보정을 위하여 최적화 모형의 수렴조건을 분석한 결과 P-S 법의 증분 감소횟수 2회가 합리적으로 나타났다. 본 모형을 충주댐 및 소양강댐의 과거 홍수사상에 대해 적용하였으며 댐지점에서 전체유역을 일괄 보정하는 방법과 댐 상류 수위국을 기준으로 나눈 중유역별로 일괄 보정하는 방법을 채택하여 분석하였다. 실시간 보정된 모형의 예측기능을 시험한 결과 상당한 오차발생의 여지가 충분하며 중유역별 매개변수의 보정은 대유역 일괄보정에 비해 예측에 따른 오차를 줄일 수 있는 방법의 하나이다. 또한 최적화 기법에 의한 매개변수의 자동 보정은 시행착오에 의한 수동보정의 경우보다 시간 및 노력면에서 효율적이며 보다 신뢰성 있는 보정을 실시 할 수 있다.

• The KIPS Transactions:PartB
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• v.10B no.6
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• pp.681-686
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• 2003

In recent years automatic image indexing and retrieval have been increasingly studied. However, content-based retrieval techniques for general images are still inadequate for many purposes. The novelty and originality of this thesis are the definition and use of a spatial information model as a contribution to the accuracy and efficiency of image search. In addition, the model is applied to represent color and shape image contents as a vector using the method of image features extraction, which was inspired by the previous work on the study of human visual perception. The indexing scheme using the color, shape and spatial model shows the potential of being applied with the well-developed algorithms of features extraction and image search, like ranking operations. To conclude, user can retrieved more similar images with high precision and fast speed using the proposed system.

• The Transactions of the Korea Information Processing Society
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• v.5 no.5
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• pp.1130-1139
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• 1998

This paper presents an integrated solution for the content-based news video indexing and the retrieval. Currently, it is impossible to automatically index a general video, but we can index a specific structural video such as news videos. Our proposed model extracts automatically the key frames by using the structured knowledge of news and consists of the news item segmentation, caption recognition and search browser modules. We present above three modules in the following: the news event segmentation module recognizes an anchor-person shot based on face recognition, and then its news event are divided by the anchor-person's frame information. The caption recognition module detects the caption-frames with the caption characteristics, extracts their character region by the using split-merge method, and then recognizes characters with OCR software. Finally, the search browser module could make a various of searching mechanism possible.

• Journal of the Korea Society of Computer and Information
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• v.19 no.6
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• pp.11-17
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• 2014

While safe and convenient, ultrasound imaging analysis is often criticized by its subjective decision making nature by field experts in analyzing musculoskeletal system. In this paper, we propose a new automatic method to extract muscle area using ART2 neural network based quantization. A series of image processing algorithms such as histogram smoothing and End-in search stretching are applied in pre-processing phase to remove noises effectively. Muscle areas are extracted by considering various morphological features and corresponding analysis. In experiment, our ART2 based Quantization is verified as more effective than other general quantization methods.

• Journal of Information Science Theory and Practice
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• v.8 no.4
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• pp.67-86
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• 2020

Information need has been one of the main motivations for a person using a search engine. Queries can represent very different information needs. Ironically, a query can be a poor representation of the information need because the user can find it difficult to express the information need. Query Expansion (QE) is being popularly used to address this limitation. While QE can be considered as a language-independent technique, recent findings have shown that in certain cases, language plays an important role. Arabic is a language with a particularly large vocabulary rich in words with synonymous shades of meaning and has high morphological complexity. This paper, therefore, provides a review on QE for Arabic information retrieval, the intention being to identify the recent state-of-the-art of this burgeoning area. In this review, we primarily discuss statistical QE approaches that include document analysis, search, browse log analyses, and web knowledge analyses, in addition to the semantic QE approaches, which use semantic knowledge structures to extract meaningful word relationships. Finally, our conclusion is that QE regarding the Arabic language is subjected to additional investigation and research due to the intricate nature of this language.