• 제목/요약/키워드: multi-layered approach

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다중 레이어 기반 제품 지식 모델 (MULTI-LAYERED PRODUCT KNOWLEDGE MODEL)

  • 이재현;서효원
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 춘계학술대회 논문집
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    • pp.65-70
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    • 2005
  • This paper introduces an approach to multi-layered product knowledge model for collaborative engineering environment. The participants in collaborative engineering want to share and reason product knowledge through internet without any heterogeneity and ambiguity. However the previous knowledge models are limited in providing those aspects. In this paper, the collaborative engineering domain is analyzed and then the product knowledge is organized into four levels such as product context model, product specific model, product design model and product manufacturing model. The four levels are represented by first-order logic in layered fashion. The concepts and the instances of a formal ontology are used for recursive representation of the four levels. The instances of the concepts of an upper level like product context model are considered as the concepts of an adjacent lower level like product specific model, and this mechanism is applied to the other levels. These logic representations are integrated with the schema and the instances of a relational database. OWL representation of the four levels is defined through the integration of the logic representation and OWL primitives. The four product knowledge models have their major representation according to the characteristics of each model. This approach enables engineer to share product knowledge through internet without any ambiguity and utilize it as basis for additional reasoning.

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Elastic solutions due to a time-harmonic point load in isotropic multi-layered media

  • Lin, Gao;Zhang, Pengchong;Liu, Jun;Wang, Wenyuan
    • Structural Engineering and Mechanics
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    • 제57권2호
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    • pp.327-355
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    • 2016
  • A new analytical derivation of the elastodynamic point load solutions for an isotropic multi-layered half-space is presented by means of the precise integration method (PIM) and the approach of dual vector. The time-harmonic external load is prescribed either on the external boundary or in the interior of the solid medium. Starting with the axisymmetric governing motion equations in a cylindrical coordinate system, a second order ordinary differential matrix equation can be gained by making use of the Hankel integral transform. Employing the technique of dual vector, the second order ordinary differential matrix equation can be simplified into a first-order one. The approach of PIM is implemented to obtain the solutions of the ordinary differential matrix equation in the Hankel integral transform domain. The PIM is a highly accurate algorithm to solve sets of first-order ordinary differential equations and any desired accuracy of the dynamic point load solutions can be achieved. The numerical simulation is based on algebraic matrix operation. As a result, the computational effort is reduced to a great extent and the computation is unconditionally stable. Selected numerical trials are given to validate the accuracy and applicability of the proposed approach. More examples are discussed to portray the dependence of the load-displacement response on the isotropic parameters of the multi-layered media, the depth of external load and the frequency of excitation.

Hybrid Shop Floor Control System for Computer Integrated Manufacturing (CIM)

  • Park, Kyung-Hyun;Lee, Seok-Hee
    • Journal of Mechanical Science and Technology
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    • 제15권5호
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    • pp.544-554
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    • 2001
  • A shop floor can be considered as an important level to develop Computer Integrated Manufacturing system (CIMs). However, a shop floor is a dynamic environment where unexpected events continuously occur, and impose changes to the planned activities. To deal with this problem, a shop floor should adopt an appropriate control system that is responsible for the coordination and control of the manufacturing physical flow and information flow. In this paper, a hybrid control system is described with a shop floor activity methodology called Multi-Layered Task Initiation Diagram (MTD). The architecture of the control model contains three levels: i.e., he shop floor controller (SFC), the intelligent agent controller (IAC) and the equipment controller (EC). The methodology behind the development of the control system is an intelligent multi-agent paradigm that enables the shop floor control system to be an independent, an autonomous, and distributed system, and to achieve an adaptability to change of the manufacturing environment.

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계층적 깊이 영상으로 표현된 다시점 영상에 대한 H.264 부호화 기술 (H.264 Encoding Technique of Multi-view Image expressed by Layered Depth Image)

  • 김민태;지인호
    • 한국인터넷방송통신학회논문지
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    • 제10권1호
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    • pp.81-90
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    • 2010
  • 본 논문에서는 계층적 깊이 영상을 H.264 기술로 부호화 시켜 압축된 데이터 크기를 확인하고, 복원된 각 영상의 품질 성능을 알아보았다. 3차원 워핑된 계층적 깊이 영상을 임계값에 따라 조정해 가면서 Filling 보간 실험을 하고 H.264 부호화 시켜 압축된 데이터 크기를 측정하였다. H.264/AVC 기술은 쉽게 비디오와 관련된 콘텐트에 대한 H.264 기술로 확장 될 수 있다. 그래서 깊이 정보를 포함하는 다시점 영상을 효과적으로 압축할 수 있는 계층적 깊이 영상 구조라는 새로운 콘텐트에 적용하는 방법을 제안하였다. 다시점 비디오 영상의 방대한 데이터 양을 감소시키며, 고품질의 영상을 제공하고, 에러 복원 기능이 강화되는 장점도 가지고 있다.

다적층 복합면재를 갖는 비등방성 샌드위치판의 휨해석 (Bending Analysis of Anisotropic Sandwich Plates with Multi-layered Laminated Composite faces)

  • 지효선
    • 복합신소재구조학회 논문집
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    • 제3권4호
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    • pp.17-26
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    • 2012
  • This study presents a governing equations of bending behavior of anisotropic sandwich plates with multi-layered laminated composite faces. Based on zig-zag models for through thickness deformations, the shear deformation of composite faces is included. All edges of plate are assumed to be simply supported. Results of the bending analysis under lateral loads are presented for the influence of various lay up sequences of antisymmetric angle-ply laminated faces. The accuracy of the approach is ascertained by comparing solutions from the sandwich plates theory with composite faces to the laminated plates theory. Since the present analysis considers the bending stiffness of the core and also the transverse shear deformations of the laminated faces, the proposed method showed higher than that calculated according to the general laminated plates theory. The information presented might be useful to design sandwich plates structure with polymer matrix composite faces.

Interfaces of Stacking $TiO_2$ Thin Layers Affected on Photocatalytic Activities

  • 주동우;부진효
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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    • pp.189.1-189.1
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    • 2013
  • Titanium dioxide (TiO2) is a wide bandgap semiconductor possessing photochemical stability and thus widely used for photocatalysis. However, enhancing photocatalytic efficiency is still a challenging issue. In general, the efficiency is affected by physio-chemical properties such as crystalline phase, crystallinity, exposed crystal facets, crystallite size, porosity, and surface/bulk defects. Here we propose an alternative approach to enhance the efficiency by studying interfaces between thin TiO2 layers to be stacked; that is, the interfacial phenomena influencing on the formation of porous structures, controlling crystallite sizes and crystallinity. To do so, multi-layered TiO2 thin films were fabricated by using a sol-gel method. Specifically, a single TiO2 thin layer with a thickness range of 20~40 nm was deposited on a silicon wafer and annealed at $600^{\circ}C$. The processing step was repeated up to 6 times. The resulting structures were characterized by conventional electron microscopes, and followed by carrying out photocatalytic performances. The multi-layered TiO2 thin films with enhancing photocatalytic efficiency can be readily applied for bio- and gas sensing devices.

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적응 뉴럴 컴퓨팅 방법을 이용한 동적 시스템의 특성 모델링 (Characteristics Modeling of Dynamic Systems Using Adaptive Neural Computation)

  • 김병호
    • 제어로봇시스템학회논문지
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    • 제13권4호
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    • pp.309-314
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    • 2007
  • This paper presents an adaptive neural computation algorithm for multi-layered neural networks which are applied to identify the characteristic function of dynamic systems. The main feature of the proposed algorithm is that the initial learning rate for the employed neural network is assigned systematically, and also the assigned learning rate can be adjusted empirically for effective neural leaning. By employing the approach, enhanced modeling of dynamic systems is possible. The effectiveness of this approach is veri tied by simulations.

Study of Mechanics of Remote Sensing and Exploring Method in Layered Medium

  • Ai-lan, LAN;Sheng-wei, ZHANG;Jing-shan, Jiang
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.1356-1358
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    • 2003
  • In the paper, a method making use of the characteristics of Dyad Green Function (DGF) and Fluctuation-Dissipation Theorem to get the brightness temperature of layered medium is introduced. Based on the approach and the measured data of multi-channel radiometer and Least Square Method (LSM), the thickness of lunar soil can be retrieved. These methods are significant to study on materials on lunar surface.

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Integrative Multi-Omics Approaches in Cancer Research: From Biological Networks to Clinical Subtypes

  • Heo, Yong Jin;Hwa, Chanwoong;Lee, Gang-Hee;Park, Jae-Min;An, Joon-Yong
    • Molecules and Cells
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    • 제44권7호
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    • pp.433-443
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    • 2021
  • Multi-omics approaches are novel frameworks that integrate multiple omics datasets generated from the same patients to better understand the molecular and clinical features of cancers. A wide range of emerging omics and multi-view clustering algorithms now provide unprecedented opportunities to further classify cancers into subtypes, improve the survival prediction and therapeutic outcome of these subtypes, and understand key pathophysiological processes through different molecular layers. In this review, we overview the concept and rationale of multi-omics approaches in cancer research. We also introduce recent advances in the development of multi-omics algorithms and integration methods for multiple-layered datasets from cancer patients. Finally, we summarize the latest findings from large-scale multi-omics studies of various cancers and their implications for patient subtyping and drug development.

다층적 모델, 전략적 니치 관리 및 필요성 인자 이론을 활용한 수소 생산 기술의 효과적 관리와 활용 방안 (Effective Management and Utilization of Hydrogen Production Technology Using Multi-layered Model, Strategic Niche Management, and Need Factor Theory)

  • 김준헌;박종화;조대명
    • 한국수소및신에너지학회논문집
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    • 제35권2호
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    • pp.129-139
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    • 2024
  • The significance of hydrogen economy and production technology is steadily increasing. This research reviewed strategies for utilizing hydrogen production technology by combining a multi-layer model, strategic niche management, and the need factor for Hoship. The model was validated as a strategy considering hydrogen production technology and the transformation of the energy system. Using this, a new business model for hydrogen production technology was created, finding a strategic niche and sophisticating the technology. It also proposed ways to unlock the potential of hydrogen production technology and improve its efficiency. This work contributes to the commercialization of hydrogen production technology and its role in sustainable energy conversion. It proposes a new and effective approach for utilizing hydrogen production technology, going beyond its limitations to suggest a more efficient method. It is hoped that these results will be helpful to researchers in hydrogen energy, and serve as a reference for establishing ways to utilize hydrogen production technology.