• Journal of the Korea Computer Graphics Society
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• v.24 no.3
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• pp.101-109
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• 2018

Recently, the improvement of virtual reality and augmented reality technologies leverages many new technologies like the virtual study room, virtual architecture room. Such virtual worlds require free handed drawing technology such as writing descriptions of formula or drawing blue print of buildings. In nature, lots of view point modifications occur when we walk around inside the virtual world. Especially, we often look some objects from near to far distance in the virtual world. Traditional drawing methods like using fixed size image for drawing unit is not produce acceptable result because they generate blurred and jaggy result as view distance varying. We propose a novel method which robust to the environment that produce lots of magnifications and minimizations like the virtual reality world. We implemented our algorithm both two dimensional and three dimensional devices. Our algorithm does not produce any artifacts, jaggy or blurred result regardless of scaling factor.

• The Journal of Information Technology
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• v.10 no.3
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• pp.33-45
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• 2007

Systolic Array Processor is used for designing the special purpose processor in Digital Signal Processing, Computer Graphics, Neural Network Applications etc., since it has the characteristic of parallelism, pipeline processing and architecture of regularity. But, in case of using general design method, it has intial waiting period as large as No. of PE-1. And if the connected system needs parallel and simultaneous outputs, processor has some problems of the performance, since it generates only one output at each clock in output state. So in this paper, one dimensional Systolic Array Processor that is designed according to the dependance of data and operations using the partitioned sub-matrix is proposed for the purpose of improving the performance. 1-D Systolic Array using 4 partitioned sub-matrix has efficient method in case of considering those two problems.

• Korean Journal of Applied Biomechanics
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• v.14 no.1
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• pp.99-115
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• 2004

In order to Know the correct swing methods in golf swing it is important to understand the whole swing path but also the concept of swing plane. But, most amateur golfers don't Know the concept of swing plane well. Therefore this study was trying to make a good material that makes the concept of swing plane easy to understand. A good swing motion data was obtained from a professional golfer using the three-dimensional DLT method. This swing motion was divided into 10 phases and evaluated using the concept of swing plane. The result of the analyze show a good matches between the path of the club and swing plane. This result was summarized as a 3 dimensional graphics to provide a good material to teach the golf swing well.

• Journal of Korea Multimedia Society
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• v.12 no.3
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• pp.335-344
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• 2009

Embedded systems and web browsers have started to provide two-dimensional vector graphics features, to finally support scalability of graphics outputs, while traditional graphics systems have focused on the raster and bitmap operations. Nowadays, SVG and Flash are actively used while OpenVG from Khronos group plays the role of a de facto low-level API standard to support them. In this paper, we represent the design and implementation process and the final results of an OpenVG implementation, AlexVG. From its design stage, our implementation aims at the cooperation with SVG-Tiny, another de facto standard for embedded systems. Currently, our overall system provides not only the OpenVG core features but also variety of OpenVG application programs and SVG-Tiny media file playing capabilities. For the conformance with the standard specifications, our system completely passed the whole OpenVG conformance test suites and the graphics output portions of the SVG-Tiny conformance test suites. From the performance point of view, we focused on the efficiency and effectiveness especially on the mobile phones and embedded devices with limited resources. As the result, it showed impressive benchmarks on the small-scale CPU's such as ARM's, even without neither any other libraries nor acceleration hardware.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.23 no.4
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• pp.375-384
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• 2005

Three dimensional urban models are being increasingly applied for various purposes such as city planning, telecommunication cell planning, traffic analysis, environmental monitoring and disaster management. In recent years, technologies from CAD and GIS are being merged to find optimal solutions in three dimensional modeling of urban buildings. These solutions include modeling of the interior building space as well as its exterior shape visualization. Research and development effort in this area has been performed by scientists and engineers from Computer Graphics, CAD and GIS. Computer Graphics and CAD focussed on precise and efficient visualization, where as GIS emphasized on topology and spatial analysis. Complementary research effort is required for an effective model to serve both visualization and spatial analysis purposes. This study presents an efficient way of using the CAD plans included in the building register documents to reconstruct the internal space of buildings. Topological information was built in the geospatial database and merged with the geometric information of CAD plans. as well as other attributal data from the building register. The GIS network modeling method introduced in this study is expected to enable an effective 3 dimensional spatial analysis of building interior which is developing with increasing complexity and size.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.3
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• pp.531-539
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• 2017

The strut-tie model approach has been recognized as an efficient methodology for the design of all types of concrete members with D-regions, and the approach has been accepted in design codes globally. However, the design of concrete members with the approach requires many iterative numerical structural analyses, numerous graphical calculations, enormous times and efforts, and designer's subjective decisions in terms of the development of appropriate strut-tie model, determination of required areas of struts and ties, and verification of strength conditions of struts and nodal zones. In this study, a computer graphics program, that enables the design of concrete members efficiently and professionally by overcoming the forementioned limitations of the strut-tie model approach, is developed. In the computer graphics program, the numerical programs that are essential in the strut-tie model analysis and design of concrete members including finite element analysis programs for the plane truss and solid problems with all kinds of boundary conditions, a program for automatic determination of effective strengths of struts and nodal zones, and a program for graphical verification of developed strut-tie model's appropriateness by displaying various geometrical shapes of struts and nodal zones, are loaded. Great efficiency and convenience during the application of the strut-tie model approach may be provided by the various graphics environment-based functions of the proposed program.

• Explosives and Blasting
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• v.39 no.2
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• pp.1-14
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• 2021

Recently, with the development of high-performance processing devices such as GPGPU, a three-dimensional dynamic analysis technique that can replace expensive rock material impact tests has been actively developed in the defense and aerospace fields. Experimentally observing or measuring fracture processes occurring in rocks subjected to high impact loads, such as blasting and earth penetration of small-diameter missiles, are difficult due to the inhomogeneity and opacity of rock materials. In this study, a three-dimensional dynamic fracture process analysis technique (3D-DFPA) was developed to simulate the fracture behavior of rocks due to impact. In order to improve the operation speed, an algorithm capable of GPGPU operation was developed for explicit analysis and contact element search. To verify the proposed dynamic fracture process analysis technique, the dynamic fracture toughness tests of the Straight Notched Disk Bending (SNDB) limestone samples were simulated and the propagation of the reflection and transmission of the stress waves at the rock-impact bar interfaces and the fracture process of the rock samples were compared. The dynamic load tests for the SNDB sample applied a Pulse Shape controlled Split Hopkinson presure bar (PS-SHPB) that can control the waveform of the incident stress wave, the stress state, and the fracture process of the rock models were analyzed with experimental results.

• The Journal of the Korea Contents Association
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• v.6 no.1
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• pp.14-22
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• 2006

The multimedia visualizational spreadsheet environment is shown to be extremely effective in supporting the organized visualization of multi-dimensional data sets. In this paper, we designed the visualization model that consists of the configurational 2D arrangement of spreadsheet elements at run time and each spreadsheet element has a novel framestack. As the feature, it supports 3D data structure of each element on the proposed model. It enables the visualization spreadsheet 1) to effectively manage, organize, and compactly encapsulate multi-dimensional data sets, 2) to reconfigure cell-structures dynamically according to client request, and 3) to rapidly process interactive user interface. Using several experiments with scientific users, the model has been demonstrated to be a highly interactive visual browsing tool for 2D and 3D graphics and rendering in each frame.

• Current Optics and Photonics
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• v.8 no.3
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• pp.246-258
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• 2024

In aerospace and energy engineering, the reconstruction of three-dimensional (3D) temperature distributions is crucial. Traditional methods like algebraic iterative reconstruction and filtered back-projection depend on voxel division for resolution. Our algorithm, blending deep learning with computer graphics rendering, converts 2D projections into light rays for uniform sampling, using a fully connected neural network to depict the 3D temperature field. Although effective in capturing internal details, it demands multiple cameras for varied angle projections, increasing cost and computational needs. We assess the impact of camera number on reconstruction accuracy and efficiency, conducting butane-flame simulations with different camera setups (6 to 18 cameras). The results show improved accuracy with more cameras, with 12 cameras achieving optimal computational efficiency (1.263) and low error rates. Verification experiments with 9, 12, and 15 cameras, using thermocouples, confirm that the 12-camera setup as the best, balancing efficiency and accuracy. This offers a feasible, cost-effective solution for real-world applications like engine testing and environmental monitoring, improving accuracy and resource management in temperature measurement.

• Journal of the Korea Computer Graphics Society
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• v.3 no.2
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• pp.45-53
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• 1997

본 논문에서는 초고속 통신망을 이용한 고급 삼차원 정보 제공을 위하여 개발한 두 가지 WWW (World Wide Web) 정보 시스템에 대하여 설명하고자 한다. 하나는 인체 골격 교육 시스템으로, 서버와 브라우저로 구성하여 인체의 골격 구성을 WWW에서 삼차원화시켜 보여주고 사용자가 원하는 부위를 직접 접근하고 관찰할 수 있게 하는 시스템 개발 방법을 기술한다. 인체 골격의 방대한 데이터를 사용자에게 효과적으로 제공하기 위한 서버 구축의 계층적 (Hierarchical) 표현 기법을 설명하고, 브라우저가 제공하는 기본 삼차원 관찰 기능 외에 인체 뼈를 절단하는 기능과 삼차원 한글, 한자, 영문 텍스트 저작기능을 설명한다. 다른 하나는 가상 건축 설계 시스템으로 이차원 도면 설계 프로그램과 서버로 구성하여 건물, 건축 형식의 이차원 도면을 작성하여 전송하면 서버에서 삼차원 건축물을 생성하여 제공하는 시스템 개발 방법을 기술한다. 이차원 도면 설계 프로그램의 객체 지향 구현 기법과 클라이언트 (Client)와 서버 (Server) 간의 통신 및 인터페이스 (Interface) 릎 구현하여, 이차원 도변을 작성하여 그에 대한 결과를 전송 하는 방법에 대하여 논한다. 인체 골격 교육 시스템은 인터넷을 통한 교육 및 의료 활용에 실제감 있는 서비스를 제공하게 되고, 가상 건축 설계 시스템으로 원거리에서도 쉽게 건축 설계 결과를 평가하여 활용할 수 있을 것이다.