• 한국전산구조공학회:학술대회논문집
• /
• 한국전산구조공학회 2007년도 정기 학술대회 논문집
• /
• pp.495-500
• /
• 2007

A Meshfree is a method used to establish algebraic equations of system for the whole problem domain without the use of a predefined mesh for the domain discretization. A point interpolation method is based on combining radial and polynomial basis functions. Involvement of radial basis functions overcomes possible singularity. Furthermore, the interpolation function passes through all scattered points in an influence domain and thus shape functions are of delta function property. This makes the implementation of essential boundary conditions much easier than the meshfree methods based on the moving least-squares approximation. This study aims to investigate a stress analysis of structural element between a meshfree method and the finite element method. Examples on cantilever type plate and stress concentration problems show that the accuracy and convergence rate of the meshfree methods are high.

• 한국산업정보학회논문지
• /
• 제12권4호
• /
• pp.126-130
• /
• 2007

연속 반복되는 시스템에서 제어하는 제어기 repetitive controller를 설계하는 방법과 시스템 안정성을 소개하고자 한다. 제어기는 반복함수로서 수렴을 조장하는 비용함수를 주파수영역에서 최소화함으로써 유도할 수 있다. 모의실험은 제안된 단수모형설계 기법을 이용한 RC를 어떻게 유도하는 것을 보여 주고 있다.

• Structural Engineering and Mechanics
• /
• 제39권5호
• /
• pp.703-716
• /
• 2011

The accurate dynamic analysis of structures is usually performed by a fine finite element discretization with very large number of degrees of freedom. Apart from modal analysis, one can reduce the number of final equations by assuming the deformed shape of the structure as a linear combination of independent Ritz vectors. The efficiency of this method relies heavily on the vectors selected. In this paper, a new set of Ritz vectors is proposed. It is primarily proved that these vectors are linearly independent. Subsequently, various two and three-dimensional examples are analyzed based on the proposed method. In each case, the results are compared with the ones obtained based on usual Ritz and modal analysis methods. It is finally concluded that the proposed method is very effective and efficient method for dynamic analysis of structures in frequency domain.

• Journal of information and communication convergence engineering
• /
• 제2권1호
• /
• pp.40-45
• /
• 2004

This paper describes a modeling of service composition manager based on TINA (Telecommunication Information Networking Architecture). The Service composition function is mainly motivated by the desire to easily generate new service using existing services from retailers or $3^{rd}$-party service providers. The TINA-C specification for the service composition does not include the detailed composition procedure and its object models. In this paper, we propose a model of components for the service composition, which adapts a static composition feature in a single provider domain. To validate the proposed modeling, we implemented prototype service composition function, which combines two multimedia services; a VOD service and a VCS service. As a result, we obtain the specification of the detailed composition architecture between a retailer domain and a $3^{rd}$-party service provider domain.

• 한국컴퓨터정보학회논문지
• /
• 제24권2호
• /
• pp.41-48
• /
• 2019

Digital image watermarking techniques have been studied in various fields in order to protect the copyright of multimedia contents mostly composed by images. JPEG compression is a representative copyright attack for image watermarking. The CRT-based watermarking methods in DCT domain have been studied, because these are robust for JPEG compression attack. In this paper, we propose a new method with improved performance compared with the existing CRT based methods in DCT domain. The proposed method selects the DCT block according to the denseness at the watermark insertion phase, and iteratively adjust the CRT Conditional coefficients at the watermark extraction. This paper shows that it is more robust for the JPEG compression attacks through experimental results.

• International journal of advanced smart convergence
• /
• 제12권3호
• /
• pp.75-88
• /
• 2023

In a specific domain, experts have different understanding of domain knowledge or different purpose of constructing ontology. These will lead to multiple different ontologies in the domain. This phenomenon is called the ontology heterogeneity. For research fields that require cross-ontology operations such as knowledge fusion and knowledge reasoning, the ontology heterogeneity has caused certain difficulties for research. In this paper, we propose a novel ontology matching model that combines word embedding and a concatenated continuous bag-of-words model. Our goal is to improve word vectors and distinguish the semantic similarity and descriptive associations. Moreover, we make the most of textual and structural information from the ontology and external resources. We represent the ontology as a graph and use the SimRank algorithm to calculate the structural similarity. Our approach employs a similarity queue to achieve one-to-many matching results which provide a wider range of insights for subsequent mining and analysis. This enhances and refines the methodology used in ontology matching.

• 한국수학교육학회지시리즈B:순수및응용수학
• /
• 제16권4호
• /
• pp.405-416
• /
• 2009

In this study we are concerned with the problem of approximating a locally unique solution of an equation in a Banach space setting using Newton's and modified Newton's methods. We provide weaker convergence conditions for both methods than before [5]-[7]. Then, we combine Newton's with the modified Newton's method to approximate locally unique solutions of operator equations. Finer error estimates, a larger convergence domain, and a more precise information on the location of the solution are obtained under the same or weaker hypotheses than before [5]-[7]. The results obtained here improve our earlier ones reported in [4]. Numerical examples are also provided.

• Structural Engineering and Mechanics
• /
• 제73권1호
• /
• pp.1-16
• /
• 2020

Finite elements based on the partition of unity (PU) approximation have powerful capabilities for p-adaptivity and solutions with high smoothness without remeshing of the domain. Recently, the PU approximation was successfully applied to the three-node shell finite element, properly eliminating transverse shear locking and showing excellent convergence properties and solution accuracy. However, the enrichment with the PU approximation results in a significant increase in the number of degrees of freedom; therefore, it requires greater computational cost, thus making it less suitable for practical engineering. To circumvent this disadvantage, we propose a new strategy to decrease the total number of degrees of freedom in the existing PU-based shell element, without loss of optimal convergence and accuracy. To alleviate the locking phenomenon, we use the method of mixed interpolation of tensorial components and perform convergence studies to show the accuracy and capability of the proposed shell element. The excellent performances of the new shell elements are illustrated in three benchmark problems.

• 디지털융복합연구
• /
• 제13권8호
• /
• pp.253-260
• /
• 2015

디지털 공간에서 개인과 조직의 활동기록이 축적되면서 활용할 수 있는 정보의 양도 폭발적으로 증가하고 있는 환경에 있어 사용자에게 가장 절실한 요구사항은 '유용한' 정보의 '효율적인' 획득에 있다. 본 논문에서는 실시간 이슈 탐지 기술을 활용하여 국방 정보 서비스로의 접목, 디지털 융복합을 시도한다. 국방 분야와 관련된 웹 상에 공개된 대량의 콘텐츠와 국방 보고서 및 DB를 연계하여 무기체계, 정책 및 훈련, 기관 및 조직 등에 대한 국방 이슈를 실시간으로 탐지하는 특화 기술을 개발하고자 한다. 이를 위해 실시간 국방 이슈 탐지 및 그룹핑 기술에 대한 요구사항을 수렴하고 분석하여 핵심 기능을 도출하고자 한다. 또한 '국방' 분야에 특화된 언어자원을 보강하고 이슈성 지수 자질을 발굴함으로써 도메인 특화 이슈 탐지 방법의 차별화를 꾀한다. 더불어 실제 수집된 웹 뉴스미디어에 기반한 국방 분야 이슈 탐지 결과와 기존 이슈 탐지 결과와 비교함으로써 그 차이를 규명하고자 한다.

• 한국동물생명공학회지
• /
• 제35권2호
• /
• pp.155-162
• /
• 2020

Equine follicle stimulating hormone receptor (eFSHR) has a large extracellular domain and an intracellular domain containing approximately 10 phosphorylation sites within the G protein-coupled receptor. This study was conducted to analyze the function of phosphorylation sties at the eFSHR C-terminal region. We constructed a mutant of eFSHR, in which the C-terminal cytoplasmic tail was truncated at residue 641 (eFSHR-t641). This removed 10 potential phosphorylation sites from the C-terminal region of the intracellular loop. The eFSHR-wild type (eFSHR-wt) and eFSHR-t641 cDNAs were subcloned into the pCMV-ARMS1-PK2 expression vector. These plasmids were transfected into PathHunter CHO-K1 Parental cells expressing β-arrestin 2 enzyme acceptor fusion protein and analyzed for agonist-induced cAMP response. The cAMP response in cells expressing eFSHR-t641 was lower than the response in cells expressing eFSHR-wt. EC₅₀ values of eFSHR-wt and eFSHR-t641 were 1079 ng/mL and 1834 ng/mL, respectively. eFSHR-t641 was approximately 0.58-fold compared with that of eFSHR-wt. The maximal response in eFSHR-wt and eFSHR-t641 was 24.7 nM and 16.7 nM, respectively. The Rmax value of phosphorylation sites in eFSHR-t641 was also decreased to approximately 68.4% of that in eFSHR-wt. The collective data implicate that the phosphorylation sites in the eFSHR C-terminal region have a pivotal role in signal transduction in PathHunter CHO-K1 cells, and indicate that β-arrestin is involved in coupling the activated receptors to the internalization system.