• Structural Engineering and Mechanics
• /
• 제74권4호
• /
• pp.559-565
• /
• 2020

This paper intends to progress models to accurately estimate the behavior of fresh concrete under vibration using artificial neural networks (ANNs). To this end, behavior of a full scale precast concrete mold was investigated numerically. Experimental study was carried out under vibration with the use of a computer-based data acquisition system. In this study measurements were taken at three points using two vibrators. Transducers were used to measure time-dependent lateral displacements at these points on mold while both mold is empty and full of fresh concrete. Modeling of empty and full mold was made using ANNs. Benefiting ANNs used in this study for modeling fresh concrete, mold design can be performed. For the modeling of ANNs: Experimental data were divided randomly into two parts such as training set and testing set. Training set was used for ANN's learning stage. And the remaining part was used for testing the ANNs. Finally, ANN modeling was compared with measured data. The comparisons show that the experimental data and ANN results are compatible.

• 한국해양공학회지
• /
• 제11권3호
• /
• pp.200-211
• /
• 1997

Most recently, offshore Engineering & Construction field is concerned about integration management technology such as CIM(Computer Integrated Manufacturing), PDM(Product Data Management) and Enterprise Information Engineering in order to cope with the rapid change of engineering and manufacturer specification as per owner's requirement during construction stage of the project. System integration and integrated data modeling with relational database in integration management technology improve the quality of product and reduce the period of the construction project by reason of owing design information jointly. This paper represents the design methodology of system integration using Business Process Reengineering by the case study. The case study is about the offshore plant material information process from front end engineering design to detail engineering for the construction and the basis of monitoring system by integrating and sharing the design information between the 2D intelligent P&ID and 3D plant modeling using relational database. As a result of the integrated data modeling and system integration, it is possible to maintain the consistency of design process in point of view of the material balancing and reduce the design assumption/duration. Near future, this system will be expanded and connected with the MRP(Material Requirement Planing) and the POR (Purchase Order Requisition) system.

• 한국전산구조공학회논문집
• /
• 제30권1호
• /
• pp.87-94
• /
• 2017

신뢰성 해석 및 신뢰성기반 최적설계는 불확실성을 고려한 확률변수를 입력 값으로 요구하며, 확률변수는 모수적 비모수적 통계모델링 방법을 사용하여 확률분포함수의 형태로 정량화 된다. 신뢰성 해석과 같은 통계적 해석은 입력되는 확률분포함수의 특성이 결과값에 영향을 미치게 되며, 확률분포함수는 통계모델링 방법에 따라 다른 형태를 가지게 된다. 본 연구에서는 모수적 통계모델링 방법인 순차적 통계모델링 방법과 비모수적 방법인 커널밀도추정을 사용하여 데이터의 개수에 따른 통계모델링의 결과를 분석하였다. 또한 수치예제를 통해 두 가지 기법에 따른 신뢰성 해석의 결과를 분석하였고, 데이터의 개수에 따른 적절한 기법을 제안하였다.

• Journal of Information Technology Applications and Management
• /
• 제9권1호
• /
• pp.85-96
• /
• 2002

Nowadays an information exchange on XML such as B2B electronic commerce is spreading. Therefore the systematic and stable management mechanism for storing the exchanged Information is needed. For this goal there are many research activities for connection between XML application and relational database. But because XML data have hierarchical structures and relational database can store only flat-structured data, we need to store XML data in object-oriented database that support hierarchical structure. Accordingly the modeling methodology for storing XML data in object-oriented database is needed. In order to build good quality application systems, modeling is an important first step. In 1997, the OMG adopted the UML as its standard modeling language. Since industry has warmly embraced UML, its popularity should become more important in the future. So a design methodology based on UML is need to develop efficiently XML applications. In this paper, we propose a unified design methodology for XML applications based on object- oriented database using UML. To this goal, first we introduce a XML modeling methodology to design W3C XML schema using UML and second we propose data modeling methodology for object-oriented database schema to store efficiently XML data in object-oriented databases.

• 사물인터넷융복합논문지
• /
• 제4권1호
• /
• pp.1-5
• /
• 2018

본 논문에서는 노이즈에 의해 훼손된 시계열 데이터의 모델링에 대하여 다룬다. 모델링 기법으로, 논싱글톤 퍼지 시스템을 사용한다. 논싱글톤 퍼지 시스템의 주요특징은 미지의 비선형시스템의 입력이 퍼지값으로 모델링 된다는데 있다. 그러므로 퍼지시스템에 인가되는 학습데이터나 입력데이터 등이 노이즈나 외부 환경에 의해 변형된 경우에 매우 유용하게 적용될 수 있다. 성능비교를 위해 벤치마크 데이터로 잘 알려진 Mackey-Glass 데이터를 사용한다. 이들 데이터 모델링을 통하여 결과를 비교, 분석하여 논싱글톤 퍼지시스템이 잡음에 대하여 보다 강인하고 효율적임을 본 논문에서 보인다.

• 지식경영연구
• /
• 제16권4호
• /
• pp.69-87
• /
• 2015

Given the huge number of data produced by its users, SNS is a great source of customer insights. Since viral trends in SNS reflect customers' direct feedback, companies can draw out highly meaningful business insights when such data is effectively analyzed and managed. However, while the importance of understanding SNS big data keeps growing, the methods for analyzing atypical data such as SNS postings for business insights over product has not been well studied. This study aims to demonstrate the way to exploit topic modeling method to support marketing strategy generation and therefore leverage business process. First, we conducted topic modeling analysis for twitter data of Apple and Samsung smartphones. Then we comparatively examined the analysis results to draw meaningful market insights about each smartphone product. Finally, we draw out a strategic marketing recommendation for each smartphone brand based on the findings.

• 한국통신학회논문지
• /
• 제35권7C호
• /
• pp.581-586
• /
• 2010

홀로그래픽 저장장치는 여러 장의 데이터 페이지가 멀티플랙싱 기법에 의하여 같은 공간에 저장된다. 그러나 이러한 데이터 저장 밀도의 증가에 따라 페이지 데이터들이 서로에게 간섭이 된다. 같은 공간에 저장되는 모든 페이지들이 서로 간섭을 주게 되며, 그에 대한 영향력을 실험 과정에서 고려해야 한다. 따라서 본 논문에서는 이러한 페이지 간의 간섭에 대한 모델링을 하며, 그에 대한 성능을 분석한다.

• Industrial Engineering and Management Systems
• /
• 제14권4호
• /
• pp.392-400
• /
• 2015

Monitoring of plasma etch processes for fault detection is one of the hallmark procedures in semiconductor manufacturing. Optical emission spectroscopy (OES) has been considered as a gold standard for modeling plasma etching processes for on-line diagnosis and monitoring. However, statistical quantitative methods for processing the OES data are still lacking. There is an urgent need for a statistical quantitative method to deal with high-dimensional OES data for improving the quality of etched wafers. Therefore, we propose a robust relevance vector machine (RRVM) for regression with statistical quantitative features for modeling etch rate and uniformity in plasma etch processes by using OES data. For effectively dealing with the OES data complexity, we identify seven statistical features for extraction from raw OES data by reducing the data dimensionality. The experimental results demonstrate that the proposed approach is more suitable for high-accuracy monitoring of plasma etch responses obtained from OES.

• 한국인터넷방송통신학회논문지
• /
• 제18권1호
• /
• pp.119-127
• /
• 2018

현업에서 사용하고 있는 정형 데이터는 데이터모델링에 대한 이해부족 및 적용의 미흡으로 정규화되지 않은 채로 테이블 형태로 관리되고 있는 현실이다. 데이터베이스 설계의 균형이 파괴되면 데이터 질의에 대한 응답속도에 영향을 미치며, 데이터 비만도가 높아지게 된다. 본 논문에서는 최적화된 데이터모델링을 통한 데이터베이스 설계를 통하여 데이터 비만도가 어떻게 개선되었는지를 연구하였다. 데이터 비만도가 과다하게 나타나는 방사형 및 업무 중심의 고립형 설계에서 객체(데이터)와 객체간의 관계 중심의 데이터모델링을 통한 정방형 설계를 함으로 데이터 질의 경로가 선명하게 가시화되었다. 데이터비만도 면에서도 기존의 연구지원 데이터베이스의 비만도는 57.2%였으나, 새로운 연구지원 데이터베이스에서는 16.2%로 나타나 데이터 비만도가 40.5%가 개선되었으며, 데이터의 중복을 최소화함으로써 데이터의 정확성과 무결성이 보장되는 데이터베이스로 개선되었다.

• 지능정보연구
• /
• 제3권2호
• /
• pp.33-55
• /
• 1997

A data model is a diagram that describes the properties of different categories of data and the associations among them within a business or information system. In spite of its importance and usefulness, data modeling activity requires not only a lot of time and effort but also extensive experience and expertise. The data models for similar business areas are analogous to one another. Therefore, it is reasonable to reuse the already-developed data models if the target business area is similar to what we have already analyzed before. In this research, we develop a case-based reasoning system for data model reuse, which we shall call CB-DM Reuser (Case-Based Data Model Reuser). CB-DM Reuse consists of four subsystems : the graphic user interface to interact with end user, the data model management system to build new data model, the case base to store the past data models, and the knowledge base to store data modeling and data model reusing knowledge. We present the functionality of CB-DM Reuser and show how it works on real-life a, pp.ication.