• 제목/요약/키워드: computer models

검색결과 3,894건 처리시간 0.033초

Package 수관 보일러의 연소실 설계에 관한 연구 (Study on Furnace Design for Packaged Water-Tube Boilers)

  • 인종수
    • 한국산업융합학회 논문집
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    • 제1권2호
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    • pp.13-19
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    • 1998
  • A computer simulation program for the design of furnace witjin pakaged water-tube boilres is developed and the developed computer program is successfully applied to design the furnace for packaged water-tube boiler. The model by experiment and the model by Hottel are used to predict the exit gas temperature of furnace. The result by two models is discussed and is shown that in the case of constant cross section in furnace, the result is same but in changing the configuration of cross section, the difference by two models is not small.

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Measurement of Rainfall Characteristics and Rain-Attenuation at 38 GHz in Worst Months Affected by El Nino Signal in 1998

  • Jang Won-Gyu;Choi Jae-Hoon
    • Journal of electromagnetic engineering and science
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    • 제5권4호
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    • pp.189-192
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    • 2005
  • The measurement of unique rainfall phenomenon and rain attenuation on 38 GHz terrestrial links at South Korea in 1998 is presented. It was one of the most severe rainfall years at the measured region due to increased EI Nino signal. The rainfall rate exceeded at $0.01\%$ was 97.4 mm/h during a worst month and annual rate was 63.5 mm/h. Experimentally measured results have been compared with some models and found that the rain attenuation by system level was underestimated by the existing prediction models. As it was measured only three months, further study and measurement of rainfall and rain attenuation in this region are needed for stable millimeter-wave system operation at all times.

소프트웨어 규모 측정 방법 연구 (A Study for Software Sizing Method)

  • 박석규;박중양
    • 한국컴퓨터산업학회논문지
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    • 제5권4호
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    • pp.471-480
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    • 2004
  • 소프트웨어 개발노력, 기간과 비용을 추정 능력은 개발될 소프트웨어의 정확한 규모 추정치 에 기반 한다. 본 논문은 소프트웨어 규모 추정을 위한 단순화된 기능점수 (FP) 기법을 제안한다. 이 기법은 가치조절인자를 계산하는 단계를 생략하고 조절인 안된 기능점수에서 조절된 기능점수를 직접 구한다. 783개의 소프트웨어 프로젝트에 기반을 둔 사례분석으로 통계적 회귀분석을 통해 적절한 모델을 찾고자 하였다. 본 논문은 또한, 신규 개발, 유지보수와 재개발 형태의 프로젝트 서브그룹별로 모델을 제시하였다.

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얇은 쉘 구조의 실시간 동적 탄성 변형 (Real-Time Elastodynamic Deformation of Thin Shell Structures)

  • 최민규;고형석;우승용
    • 한국컴퓨터그래픽스학회논문지
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    • 제12권1호
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    • pp.21-25
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    • 2006
  • This paper proposes a real-time simulation technique for thin shells undergoing large deformation. Thin shells are almost two-dimensional structures visually well approximated as surfaces, such as leaves, paper sheets, hats, aluminum cans. Unfortunately accurate simulation of these structures requires one of the most complex formulations in continuum mechanics, shell theory [4]. Moreover, there has not yet been any work reported to produce visually convincing animation of them while achieving real-time performance. Motivated by discrete shells [5] and modal warping [3], we formulate dynamics of thin shells using mass-spring models instead of finite element models, and then apply the modal warping technique to cope with large rotational deformation of thin shells. Experiments show that the proposed technique runs in real-time, and that it can simulate large bending and/or twisting deformations with acceptable realism.

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Development of Flexible Manufacturing System using Virtual Manufacturing Paradigm

  • Kim, Sung-Chung;Park, Kyung-Hyun
    • International Journal of Precision Engineering and Manufacturing
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    • 제1권1호
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    • pp.84-90
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    • 2000
  • The importance of Virtual Manufacturing System is increasing in the area of developing new manufacturing processes, implementing automated workcells, designing plant facility layouts and workplace ergonomics. Virtual manufacturing system is a computer system that can generate the same information about manufacturing system structure, states, and behaviors as is observed in a real manufacturing. In this research, a virtual manufacturing system for flexible manufacturing cells (VFMC), (which is a useful tool for building Computer Integrated Manufacturing (CIM), has been developed using object-oriented paradigm, and implemented with software QUEST/IGRIP. Three object models used in the system are the product model, the facility model, and the process model. The concrete behaviors of a flexible manufacturing cell are re[presented by the task-oriented description diagram, TIC. An example simulation is executed to evaluate applicability of the developed models, and to prove the potential value of virtual manufacturing paradigm.

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GPS-based 3D View Augmented Reality System for Smart Mobile Devices

  • Vo, Phuc;Choi, Chang Yeol
    • International Journal of Contents
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    • 제9권1호
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    • pp.18-25
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    • 2013
  • Recently, augmented reality has been proved immensely useful on a day to day basis when tied with location-based technology. In this paper, we present a new method for displaying augmented reality contents on mobile devices. We add 3D models on the view of the camera and use location-based services, motion sensors to calculate the transformation of models. Instead of remaining at a fixed position on camera view while moving around a 3D model, the model rotates on display in the opposite direction that the user is walking. We also design client as a ubiquitous client to reduce constraints on disk space and memory capacity on mobile devices. Implementation results show effective use in creating GPS-based 3D view augmented reality contents for Smart Mobile Devices.

City-Scale Modeling for Street Navigation

  • Huang, Fay;Klette, Reinhard
    • Journal of information and communication convergence engineering
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    • 제10권4호
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    • pp.411-419
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    • 2012
  • This paper proposes a semi-automatic image-based approach for 3-dimensional (3D) modeling of buildings along streets. Image-based urban 3D modeling techniques are typically based on the use of aerial and ground-level images. The aerial image of the relevant area is extracted from publically available sources in Google Maps by stitching together different patches of the map. Panoramic images are common for ground-level recording because they have advantages for 3D modeling. A panoramic video recorder is used in the proposed approach for recording sequences of ground-level spherical panoramic images. The proposed approach has two advantages. First, detected camera trajectories are more accurate and stable (compared to methods using multi-view planar images only) due to the use of spherical panoramic images. Second, we extract the texture of a facade of a building from a single panoramic image. Thus, there is no need to deal with color blending problems that typically occur when using overlapping textures.

Vehicle Manufacturer Recognition using Deep Learning and Perspective Transformation

  • Ansari, Israfil;Shim, Jaechang
    • Journal of Multimedia Information System
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    • 제6권4호
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    • pp.235-238
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    • 2019
  • In real world object detection is an active research topic for understanding different objects from images. There are different models presented in past and had significant results. In this paper we are presenting vehicle logo detection using previous object detection models such as You only look once (YOLO) and Faster Region-based CNN (F-RCNN). Both the front and rear view of the vehicles were used for training and testing the proposed method. Along with deep learning an image pre-processing algorithm called perspective transformation is proposed for all the test images. Using perspective transformation, the top view images were transformed into front view images. This algorithm has higher detection rate as compared to raw images. Furthermore, YOLO model has better result as compare to F-RCNN model.

CEMTool 환경에서 3D FEM 패키지 구현에 관하여 (On the Implementation of 3D FEM Package for CEMTool)

  • 박정훈;권욱현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 D
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    • pp.2897-2899
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    • 2005
  • Finite element method (FEM) has been widely used as a useful numerical method that can analyze complex engineering problems in electro-magnetics, mechanics, and others. CEMTool, which is similar to MATLAR, is a command style design and analyzing package for scientific and technological algorithm and a matrix based computation language. In this paper, we present new 3D FEM package in CEMTool environment. In contrast to the existing CEMTool 2D FEM package and MATLAB PDE (Partial Differential Equation) Toolbox, our proposed 3D FEM package can deal with complex 3D models, not a cross-section of 3D models. Consequently, with our new 3D FEM toolbox, we can analyze more diverse engineering Problems which the existing CEMTool 2D FEM package or MATLAB PDE Toolbox can not solve.

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One-to-All Broadcasting in Petersen-Torus Networks for SLA and MLA Models

  • Seo, Jung-Hyun;Lee, Hyeong-Ok
    • ETRI Journal
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    • 제31권3호
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    • pp.327-329
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    • 2009
  • In a network, broadcasting is the dissemination of a message from a source node holding a message to all the remaining nodes through a call. This letter proposes a one-to-all broadcasting algorithm in the Petersen-torus network PT(n, n) for the single-link-available and multiple-link-available models. A PT(n, n) is a regular network whose degree is 4 and number of nodes is $10n^2$, where the Petersen graph is set as a basic module, and the basic module is connected in the form of a torus. A broadcasting algorithm is developed using a divide-and-conquer technique, and the time complexity of the proposed algorithm approximates n+4, the diameter of PT(n, n), which is the lower bound of the time complexity of broadcasting.

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