• 한국정보과학회논문지:시스템및이론
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• 제28권4호
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• pp.181-187
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• 2001

본 논문에서는 3D 텍스쳐 매핑 하드웨어(texture mapping hardware)하에서 OpenGL를 이용하여 빠른 추출(classification) 및 음영처리(shading)를 가능하게 하는 직접 볼륨 렌더링(direct volume rendering) 방법을 제안한다. 추출과정을 위해 lookup table을 통해서 볼륨 데이터의 밀도값(density)으로부터 불투명도(opacity)값을 얻어내고, 법선 벡터 블렌딩(normal blending)방법을 제안하여 볼륨 크기에 상관없이 최종 이미지에서만 음영 처리 연산을 수행한다. 본 논문에서 제시된 볼륨 렌더링의 전과정이 그래픽스 하드웨어(graphics hardware)에서 이뤄지면, 음영처리 연산의 복잡도 감소로 인하여 상호 대화적인 볼륨 렌더링이 가능하다.

• Journal of Mechanical Science and Technology
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• 제17권10호
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• pp.1496-1506
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• 2003

The SIMP (solid isotropic material with penalization) approach is perhaps the most popular density variable relaxation method in topology optimization. This method has been very successful in many applications, but the optimization solution convergence can be improved when new variables, not the direct density variables, are used as the design variables. In this work, we newly propose S-shape functions mapping the original density variables nonlinearly to new design variables. The main role of S-shape function is to push intermediate densities to either lower or upper bounds. In particular, this method works well with nonlinear mathematical programming methods. A method of feasible directions is chosen as a nonlinear mathematical programming method in order to show the effects of the S-shape scaling function on the solution convergence.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권11호
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• pp.2941-2956
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• 2013

In this paper, we propose an effective fragile image watermarking scheme for tampering detection and content recovery. Cover image is divided into a series of non-overlapping blocks and a block mapping relationship is constructed by the secret key. Several DCT coefficients with direct current and lower frequencies of the MSBs for each block are used to generate the reference bits, and different coefficients are assigned with different bit numbers for representation according to their importance. To enhance recovery performance, authentication bits are generated by the MSBs and the reference bits, respectively. After LSB substitution hiding, the embedded watermark bits in each block consist of the information of itself and its mapping blocks. On the receiver side, all blocks with tampered MSBs can be detected and recovered using the valid extracted reference bits. Experimental results demonstrate the effectiveness of the proposed scheme.

• 대한음성학회지:말소리
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• 제48호
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• pp.93-105
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• 2003

Since telephone channel has bandlimited frequency characteristics, speech signal over the telephone channel shows degraded speech quality. In this paper, we propose an algorithm using neural network to reconstruct wideband speech from its narrowband version. Although single neural network is a good tool for direct mapping, it has difficulty in training for vast and complicated data. To alleviate this problem, we modularize the neural networks based on appropriate clustering of the acoustic space. We also introduce fuzzy computing to compensate for probable misclassification at the cluster boundaries. According to our simulation, the proposed algorithm showed improved performance over the single neural network and conventional codebook mapping method in both objective and subjective evaluations.

• 대한수학회보
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• 제50권3호
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• pp.993-1005
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• 2013

In this paper, to include more generalized cases, the authors present a modified concept for the tripled and quadruple fixed point of the mixed monotone mappings. Also, they investigate the existence and uniqueness of fixed point of the ordered monotone operator with the Matkowski contractive conditions in the partial ordered metric spaces. As the direct consequences, the existence of coupled fixed point, tripled fixed point and quadruple fixed point are explored at the common framework and some previous results in [T. G. Bhaskar and V. Lakshmikan-tham, Fixed point theory in partially ordered metric spaces and applications, Nonlinear Anal. 65 (2006), 1379-1393; V. Berinde and M. Borcut, Tripled fixed point theorems for contractive type mappings in partially ordered metric spaces, Nonlinear Anal. 74 (2011), no. 15, 4889-4897; E. Karapinar and N. V. Luong, Quadruple fixed point theorems for nonlinear contractions, Computers and Mathematics with Applications (2012), doi:10.1016/j.camwa.2012.02061] are improved. Finally, some fixed point theorems are proved.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 춘계학술대회논문집 - 한국공작기계학회
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• pp.679-684
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• 2000

This paper presents the development of system and program for a Parallel-Typed CNC Machine. The system consists of parallel manipulator, PC (Personal Computer), DMC (DSP Motion Controller), and machining tools. In order to control the manipulator, the program, which is implemented in "c/c++" language, involves inverse/direct kinematics, velocity mapping, Jacobian and etc. A controller computes the kinematic formulation in real-time and generates and motion by the DMC. A monitor, which has access to program and sensory information, displays the status of manipulator.nipulator.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2010년 춘계학술발표회 논문집
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• pp.207-208
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• 2010

In this paper, we carried out calibration of laser scanning MMS(Mobile Mapping System) using Lynx Mobile Mapper, a new MMS developed at Optech Incorporated. Laser scanning MMS could be defined as an integration of several subsystems. Subsystems are composed of laser scanner, gps receiver and antenna, INS(Inertial Navigation System), DMI(Distance Measurement Instrument). These are obtained 3D spatial information by direct-georeferencing technology. To obtain 3D spatial information, calibration of laser scanning MMS is required prior to operation system, it is similar to airborme lidar system. 145 checkpoints were used to accuracy estimation. The accuracy results are about 5cm(RMSE) for calibration in all directions(east, north, ellipsoidal height).

• Journal of information and communication convergence engineering
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• 제5권3호
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• pp.249-253
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• 2007

The Research on the ICT(Information & Communication Technology) is proposed the category to IT839 strategy by Government. Government is driving to researching on technology about IT839 Strategy. By transforming this category and research information into Semantic Web environment, it is possible to search function utilizing knowledge base and information object by use of TBox and ABox. In this regard, this study proposes technology for generation of Semantic Web Document about ICT Research Information. The ontology is constructed by using category to IT839 Strategy. The features of framework proposed in this study is to have used a skill to directly map Ontology instance and in case of inability of direct mapping, proposed a skill to establish reliable Semantic Web Document by suggesting indirect mapping skill using mechanical study. In addition, it is possible to establish low cost/high quality Semantic Web Document about ICT research information.

• 전자공학회논문지C
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• 제35C권12호
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• pp.1-12
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• 1998

본 논문은 VHDL 컴파일러 시스템에서 후반부의 VHDL-to-C 사상 과정을 설계 및 구현한 연구에 관하여 기술한다. 컴파일러 전반부가 VHDL 설계 프로그램으로부터 발생시킨 중간 형식의 분석 데이터는 컴파일러 후반부의 VHDL-to-C 사상을 통해서 VHDL 어의가 구현된 C 코드 모델로 변환된다. 기본적으로 VHDL 어의를 표현하기 위한 C 코드 모델은 선언부, 구축부, 초기화부 및 실행부의 4개 기능적 템플릿으로 구성된다. 사상 과정에서는 사상 단위와 기능분류에 따른 129개 C 사상 템플릿과 반복적 알고리듬을 통하여 터미널 정보를 이용해서 C 코드를 생성하게 된다. C 프로그램의 구성은 코드를 직접 템플릿으로 출력하거나, 생성된 코드를 데이터큐에 중간 저장시키고 상위사상 결과에 결합시켜서 이루어진다. 설계 및 구현된 VHDL-to-C 사상기는 Validation Suite의 96% VHDL 구문 구조에 대해서 100% C 코드 모델을 완벽하게 사상할 수 있음을 보였다. 또한 VHDL-to-C 사상의 성능에서 생성된 코드의 메모리 오버헤드가 해석기 방식보다는 작고 직접코드 방식보다는 크지만 VHDL 프로그램 크기에 대해서 완만한 증가 경향을 보이고 있으며, 사상처리 시간에서는 사상 메카니즘의 구현에서 최적화 및 개선이 요구됨을 나타내었다.

• 정보처리학회논문지B
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• 제10B권7호
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• pp.803-810
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• 2003

본 논문에서는 일반 PC에서 방사형으로 배치된 카메라를 통해 획득되는 비디오 영상을 하나의 대형 고해상도 영상으로 만드는 실시간 영상모자익 기법에 관해 기술한다. 제안된 방법은 먼저 위상 상관 알고리즘을 사용하여 인접하는 두 영상간의 수평 및 수직 이동거리를 산출한 다음, Levenberg-Marquardt 방법을 사용하여 카메라 사이의 정확한 변환 행렬을 계산한다. 마지막으로 DirectX의 텍스처 매핑 함수에 변환행렬을 적용하여 입력영상들을 하나의 대형 영상으로 합성한다. 이 방법은 특징은 일반 개인용 컴퓨터에서 널리 사용되고 있는 그래픽 API DirectX를 영상 합성과정에 이용하기 때문에 특별한 장치와 기계어 수준의 프로그래밍 없이도 실시간 영상 모자익을 구현할 수 있다는 것이다.