• Title/Summary/Keyword: domain model

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Filling Holes in Large Polygon Models Using an Implicit Surface Scheme and the Domain Decomposition Method

  • Yoo, Dong-Jin
    • International Journal of Precision Engineering and Manufacturing
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    • v.8 no.1
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    • pp.3-10
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    • 2007
  • A new approach based on implicit surface interpolation combined with domain decomposition is proposed for filling complex-shaped holes in a large polygon model, A surface was constructed by creating a smooth implicit surface from an incomplete polygon model through which the actual surface would pass. The implicit surface was defined by a radial basis function, which is a continuous scalar-value function over the domain $R^{3}$. The generated surface consisted of the set of all points at which this scalar function is zero. It was created by placing zero-valued constraints at the vertices of the polygon model. The well-known domain decomposition method was used to treat the large polygon model. The global domain of interest was divided into smaller domains in which the problem could be solved locally. The LU decomposition method was used to solve the set of small local problems; the local solutions were then combined using weighting coefficients to obtain a global solution. The validity of this new approach was demonstrated by using it to fill various holes in large and complex polygon models with arbitrary topologies.

Product data model for PLM system

  • Li, Yumei;Wan, Li;Xiong, Tifan
    • International Journal of CAD/CAM
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    • v.11 no.1
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    • pp.1-10
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    • 2011
  • Product lifecycle management (PLM) is a new business strategy for enterprise's product R&D. A PLM system holds and maintaining the integrity of the product data produced throughout its entire lifecycle. There is, therefore, a need to build a safe and effective product data model to support PLM system. The paper proposes a domain-based product data model for PLM. The domain modeling method is introduced, including the domain concept and its defining standard along the product evolution process. The product data model in every domain is explained, and the mapping rules among these models are discussed. Mapped successively among these models, product data can be successfully realized the dynamic evolution and the historical traceability in PLM system.

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Sequential Feasible Domain Sampling of Kriging Metamodel by Using Penalty Function (벌칙함수 기반 크리깅메타모델의 순차적 유용영역 실험계획)

  • Lee Tae-Hee;Seong Jun-Yeob;Jung Jae-Jun
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.30 no.6 s.249
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    • pp.691-697
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    • 2006
  • Metamodel, model of model, has been widely used to improve an efficiency of optimization process in engineering fields. However, global metamodels of constraints in a constrained optimization problem are required good accuracy around neighborhood of optimum point. To satisfy this requirement, more sampling points must be located around the boundary and inside of feasible region. Therefore, a new sampling strategy that is capable of identifying feasible domain should be applied to select sampling points for metamodels of constraints. In this research, we suggeste sequential feasible domain sampling that can locate sampling points likely within feasible domain by using penalty function method. To validate the excellence of feasible domain sampling, we compare the optimum results from the proposed method with those form conventional global space-filling sampling for a variety of optimization problems. The advantages of the feasible domain sampling are discussed further.

A Study on Filling Holes of Large Polygon Model using Implicit Surface Scheme and Domain Decomposition Method (음함수 곡면기법과 영역 분할법을 이용한 대형 폴리곤 모델의 홀 메움에 관한 연구)

  • Yoo Dong-Jin
    • Journal of the Korean Society for Precision Engineering
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    • v.23 no.1 s.178
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    • pp.174-184
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    • 2006
  • In order to fill the holes with complex shapes in the large polygon model, a new approach which is based on the implicit surface interpolation method combined with domain decomposition method is presented. In the present study, a surface is constructed by creating smooth implicit surface from the incomplete polygon model through which the surface should pass. In the method an implicit surface is defined by a radial basis function, a continuous scalar-valued function over the domain $R^3$ The generated surface is the set of all points at which this scalar function takes on the value zero and is created by placing zero-valued constraints at the vertices of the polygon model. In this paper the well-known domain decomposition method is used in order to treat the large polygon model. The global domain of interest is divided into smaller domains where the problem can be solved locally. LU decomposition method is used to solve a set of small local problems and their local solutions are combined together using the weighting coefficients to obtain a global solution. In order to show the validity of the present study, various hole fillings are carried out fur the large and complex polygon model of arbitrary topology.

Application of transfer learning for streamflow prediction by using attention-based Informer algorithm

  • Fatemeh Ghobadi;Doosun Kang
    • Proceedings of the Korea Water Resources Association Conference
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    • 2023.05a
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    • pp.165-165
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    • 2023
  • Streamflow prediction is a critical task in water resources management and essential for planning and decision-making purposes. However, the streamflow prediction is challenging due to the complexity and non-linear nature of hydrological processes. The transfer learning is a powerful technique that enables a model to transfer knowledge from a source domain to a target domain, improving model performance with limited data in the target domain. In this study, we apply the transfer learning using the Informer model, which is a state-of-the-art deep learning model for streamflow prediction. The model was trained on a large-scale hydrological dataset in the source basin and then fine-tuned using a smaller dataset available in the target basin to predict the streamflow in the target basin. The results demonstrate that transfer learning using the Informer model significantly outperforms the traditional machine learning models and even other deep learning models for streamflow prediction, especially when the target domain has limited data. Moreover, the results indicate the effectiveness of streamflow prediction when knowledge transfer is used to improve the generalizability of hydrologic models in data-sparse regions.

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Multi-Domain Model for Electric Traction Drives Using Bond Graphs

  • Silva, Luis I.;De La Barrera, Pablo M.;De Angelo, Cristian H.;Aguilera, Facundo;Garcia, Guillermo O.
    • Journal of Power Electronics
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    • v.11 no.4
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    • pp.439-448
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    • 2011
  • In this work the Multi-Domain model of an electric vehicle is developed. The electric domain model consists on the traction drive and allows including faults associated with stator winding. The thermal model is based on a spatial discretization. It receives the power dissipated in the electric domain, it interacts with the environment and provides the temperature distribution in the induction motor. The mechanical model is a half vehicle model. Given that all models are obtained using the same approach (Bond Graph) their integration becomes straightforward. This complete model allows simulating the whole system dynamics and the analysis of electrical/mechanical/thermal interaction. First, experimental results are aimed to validate the proposed model. Then, simulation results illustrate the interaction between the different domains and highlight the capability of including faults.

The Application of Work Domain Analysis for the Development of Vehicle Control Display (자동차 계기판 개발을 위한 WDA (Work Domain Analysis) 적용)

  • Nam, Taek-Su;Myung, Ro-Hae;Hong, Seung-Kweon
    • Journal of the Ergonomics Society of Korea
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    • v.26 no.4
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    • pp.127-133
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    • 2007
  • The purpose of this study is to apply WDA (Work Domain Analysis) for the development of EID (Ecological Interface Design) of vehicle control display. At first, a work domain model on the automobile operation was developed using the AH (Abstraction Hierarchy) which is one of WDA tools. Secondly, information requirements that should be included in vehicle control displays were extracted on the basis of the completed model. The vehicle control information that typical automobiles interface displays currently provide occurred on the low level of the work domain model. This implies that current control displays impose too heavy cognitive workload on automobile drivers. Information requirements that can be included new vehicle control display are also discovered in the high level of the work domain model. The detailed information for EID was not proposed in this study. In the further study, the development of vehicle control display will be deeply conducted, using the results of this study.

A Conceptual Modeling Tools for the Model Base Design (모델베이스 설계를 위한 개념적 모델링 도구에 관한 연구)

  • 정대율
    • The Journal of Information Systems
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    • v.7 no.1
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    • pp.181-208
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    • 1998
  • In many literatures of model management, various schemes for representing model base schema have proposed. Ultimately, the goal is to arrive at a set of mutually supportive and synergistic methodologies and tools for the modeling problem domain and model base design. This paper focus on how best to structure and represent conceptual model of problem domain and schema of model base. Semantic concepts and modeling constructs are valuable conceptual tools for understanding the structural relationships and constraints involved in an model management environment. To this end, we reviewed the model management literature, and analyzed the constructs of modeling tools of data model management graph-based approach. Although they have good tools but most of them are not enough for the representation of structural relationships and constraints. So we wanted more powerful tools which can represent diverse constructs in a decision support modeling and model base schema design. For the design of a model base, we developed object modeling framework which uses Object Modeling Techniques (OMT). In Object Modeling Framework, model base schema are classified into conceptual schema, logical schema, and physical schema. The conceptual schema represents the user's view of problem domain, and the logical schema represents a model formatted by a particular modeling language. The schema design, this paper proposes an extension of Object Model to overcome some of the limitations exhibited by the OMT. The proposed tool, Extended Object Model(EOM) have diverse constructs for the representation of decision support problem domain and conceptual model base schema.

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A frequency domain adaptive PID controller based on non-parametric plant model representation

  • Egashira, Toyokazu;Iwai, Zenta;Hino, Mitsushi;Takeyama, Yoshikazu;Ono, Taisuke
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10a
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    • pp.165-168
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    • 1996
  • In this paper, we propose a design method of PID adaptive controller based on frequency domain analysis. The method is based on the estimation of a nonparametric process model in the frequency domain and the determination of the PID controller parameters by achieving partial model matching so as to minimize a performance function concerning to relative model error between the loop transfer function of the control system and the desired system. In the design method the process is represented only by a discrete set of points on the Nyquist curve of the process. Therefore it is not necessary to estimate a full order parameterized process model.

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Learning Domain Invariant Representation via Self-Rugularization (자기 정규화를 통한 도메인 불변 특징 학습)

  • Hyun, Jaeguk;Lee, ChanYong;Kim, Hoseong;Yoo, Hyunjung;Koh, Eunjin
    • Journal of the Korea Institute of Military Science and Technology
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    • v.24 no.4
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    • pp.382-391
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    • 2021
  • Unsupervised domain adaptation often gives impressive solutions to handle domain shift of data. Most of current approaches assume that unlabeled target data to train is abundant. This assumption is not always true in practices. To tackle this issue, we propose a general solution to solve the domain gap minimization problem without any target data. Our method consists of two regularization steps. The first step is a pixel regularization by arbitrary style transfer. Recently, some methods bring style transfer algorithms to domain adaptation and domain generalization process. They use style transfer algorithms to remove texture bias in source domain data. We also use style transfer algorithms for removing texture bias, but our method depends on neither domain adaptation nor domain generalization paradigm. The second regularization step is a feature regularization by feature alignment. Adding a feature alignment loss term to the model loss, the model learns domain invariant representation more efficiently. We evaluate our regularization methods from several experiments both on small dataset and large dataset. From the experiments, we show that our model can learn domain invariant representation as much as unsupervised domain adaptation methods.