• Title/Summary/Keyword: Computer Modelling

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Design of Advanced Multiplicative Inverse Operation Circuit for AES Encryption (AES 암호화를 위한 개선된 곱셈 역원 연산기 설계)

  • Kim, Jong-Won;Kang, Min-Sup
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.20 no.4
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    • pp.1-6
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    • 2020
  • This paper proposes the design of an advanced S-Box for calculating multiplicative inverse in AES encryption process. In this approach, advanced S-box module is first designed based on composite field, and then the performance evaluation is performed for S-box with multi-stage pipelining architecture. In the proposed S-Box architecture, each module for multiplicative inverse is constructed using combinational logic for realizing both small-area and high-speed. Through logic synthesis result, the designed 3-stage pipelined S-Box shows speed improvement of about 28% compared to the conventional method. The proposed advanced AES S-Box is performed modelling at the mixed level using Verilog-HDL, and logic synthesis is also performed on Spartan 3s1500l FPGA using Xilinx ISE 14.7 tool.

Modelling Perceptual Attention for Augmented Reality Agents (증강 현실 에이전트를 위한 지각 주의 모델링)

  • Oh, Se-Jin;Woo, Woon-Tack
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.47 no.3
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    • pp.51-58
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    • 2010
  • Since Augmented Reality (AR) enables users to experience computer-generated content embedded in real environments, AR agents can be visualized among physical objects in the environments where the users exist, and directly interact with them in real-time. We model perceptual attention for autonomous agents in AR environments where virtual and physical objects coexist. Since such AR agents must adaptively perceive and attend to surrounded objects relevant to their goals, our model allows the agents to determine currently visible objects from the description of what virtual and physical objects are configured in the camera's viewing area. A degree of attention is assigned to each perceived object based on its relevance to achieve agents' goals. The agents can focus on a reduced set of perceived objects with respect to the estimated degree of attention. To demonstrate the effectiveness of our approach, we implemented an animated character that was overlaid over a miniature version of campus and that attended to buildings relevant to their goals. Experiments showed that our model could reduce the character's perceptual loads even when surroundings change.

Behaviour of Leaking Tunnels under Unconfined Flow Condition (비구속 흐름조건하에 있는 배수형 터널의 거동)

  • Shin Jong-Ho
    • Journal of the Korean Geotechnical Society
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    • v.21 no.7
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    • pp.43-54
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    • 2005
  • Tunnelling in a water bearing soil may cause draw-down of ground water table. Modelling of this problem requires considering the change of phreatic surface including the stress constitutive relationship for an unsaturated soil. However, it is normally assumed that ground water is confined. Numerical formulation of coupled behavior considering phreatic surface is described and implemented into computer program. Influence of unconfined flow on tunnel and ground is thoroughly investigated and compared with that of confined flow condition. It is identified that ground and lining behaviour below phreatic surface is almost the same as that under confined flow conditions, however, there is considerable difference in ground behaviour above phreatic surface. It is generally concluded that the assumption of confined flow is acceptable in terms of lining design.

An Object Tracking Method for Studio Cameras by OpenCV-based Python Program (OpenCV 기반 파이썬 프로그램에 의한 방송용 카메라의 객체 추적 기법)

  • Yang, Yong Jun;Lee, Sang Gu
    • The Journal of the Convergence on Culture Technology
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    • v.4 no.1
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    • pp.291-297
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    • 2018
  • In this paper, we present an automatic image object tracking system for Studio cameras on the stage. For object tracking, we use the OpenCV-based Python program using PC, Raspberry Pi 3 and mobile devices. There are many methods of image object tracking such as mean-shift, CAMshift (Continuously Adaptive Mean shift), background modelling using GMM(Gaussian mixture model), template based detection using SURF(Speeded up robust features), CMT(Consensus-based Matching and Tracking) and TLD methods. CAMshift algorithm is very efficient for real-time tracking because of its fast and robust performance. However, in this paper, we implement an image object tracking system for studio cameras based CMT algorithm. This is an optimal image tracking method because of combination of static and adaptive correspondences. The proposed system can be applied to an effective and robust image tracking system for continuous object tracking on the stage in real time.

Hydraulic Design of Culvert Size (암거 규격의 수리 설계)

  • Yoo, Dong-Hoon;Kim, Jong-Hee
    • Journal of Korea Water Resources Association
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    • v.43 no.3
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    • pp.275-282
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    • 2010
  • The purpose of culvert design is to determine optimum size for a safe drainage of flood discharge. The present method of culvert design in Korea is generally carried out by using "Road Drainage Design" of Korea Expressway Corporation (1991), which is based on the manual of Federal Highway Association (FHWA) of USA. However, this method may result in subjective error because of using graphs and the usage of nomograph can be a major obstacle for computer modelling. Some errors found in the previous works of culvert design are corrected, and a new logic has been developed for a simple determination of culvert size in this study. FHWA (1985) presents a nomograph to determine the critical water depth and the velocity head for a circular pipe, but in this study simple explicit equations have been developed to determine both respectively.

The 3D Modelling of Cultural Heritage Using Digital Photogrammetry (수치사진측량기법을 이용한 문화재의 3차원 모델링에 관한 연구)

  • 김진수;박운용;홍순헌
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.21 no.4
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    • pp.365-371
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    • 2003
  • Digital high resolution cameras are widely available, and are increasingly use in digital close-range photogrammetry. And photogrammetry instruments are developing rapidly and the precision is improving continuously. The building of 3D terrains of high precision are possible and the calculation of the areas or the earthwork volumes have high precision due to the development of the techlique of the spatial information system using computer. Using the digital camera which has capacity of keeping numerical value by itself and easy carrying, we analyze the positioning error according to various change of photographing condition. Also we try to find a effective method of acquiring basis data for 3D monitoring of high-accuracy in pixel degree through digital close-range photogrammetry with bundle adjustment for local terrain model generation and 3D embodiment of tumulus. In the study is about to efficient analysis of digital information data fer conservation of cultural properties.

Converged Influencing Factors on the Career Commitment of General Hospital Nurses with Preschool Children (미취학 자녀를 둔 종합병원 간호사의 경력몰입에 미치는 융합적 영향요인)

  • So, Ja-Young;Ha, Yun-Ju
    • Journal of the Korea Convergence Society
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    • v.11 no.5
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    • pp.341-351
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    • 2020
  • This study aimed to identify the parenting competence and parenting stress of nurses in general hospital with preschool children, and to identify convergent factors affecting career commitment. A cross-sectional design was used with a convenience sample of 214 nurses from seven general hospitals. Data were collected through self-evaluation questionnaires from August 10 to August 31, 2016 and analyzed using descriptive statistics, t-test, one-way ANOVA, Pearson's correlation coefficient, and structural modelling using the SPSS WIN 18.0 and AMOS 18.0 computer programs. Parenting stress had a full mediating effect on the influence of parenting competency on career commitment. It is expected to be used as a basic data for improving career commitment of nurses in general hospitals with preschool children, and further studies on factors affecting career commitment, including job-related characteristics, along with parenting-related factors, will be needed.

A Study on the Weight Optimization for the Passenger Car Seat Frame Part (상용승용차 시트프레임 부품의 중량 최적화에 관한 연구)

  • Jang, In-Sik;Min, Byeong-Jo
    • Transactions of the Korean Society of Automotive Engineers
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    • v.14 no.5
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    • pp.155-163
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    • 2006
  • Car seat is one the most important element to make comfortable drivability. It can absorb the impact or vibration during driving state. In addition to those factors, it is needed to have enough strength for passenger safety. From energy efficiency and environmental point of view lighter passenger car seat frame becomes hot issue in the auto industry. In this paper, weight optimization methodology is investigated for commercial car seat frame using CAE. Optimized designs for seat frame are developed using commercially available finite element code(ANSYS) and design of experiment method. At first, car seat frame is modelled using 3-D computer aided design tool(CATIA) and simplified for finite element modelling. Finite element analysis is carried out for the case of FMVSS 202 Head Restraint test to check the strength of the original seat frame. Two base brackets are selected as optimized elements that are the heaviest parts in the seat frame. After finite element analysis for the brackets with similar load condition to the previous test optimization technique is applied for 10% to 50% weight reduction. Design of experiment is utilized to obtain optimization design for the bracket based on the modified 50% weight reduction model in which outer shape of the bracket is conserved. Weight optimization models result in the decrease of the strength in spite of weight reduction. The more design points should be considered to get better optimized model. The more advanced optimization technique may be utilized for more parts of the seat frame to increase whole seat frame characteristics in the future.

Towards the development of an accurate DEM generation system from KOMPSAT-1 Electro-Optical Camera Data (다목적 실용위성 1호기 EOC카메라 영상으로부터 DEM 추출을 위한 시스템개발에 관한 고찰)

  • Taejung Kim;Heung Kyu Lee
    • Korean Journal of Remote Sensing
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    • v.14 no.3
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    • pp.232-249
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    • 1998
  • The first Korean remote sensing satellite, Korea Multi-Purpose Satellite (KOMPSAT-1), is going to be launched in 1999. This will carry a 7m resolution Electro-Optical Camera (EOC) for earth observation. The primary mission of the KOMPSAT-1 is to acquire stereo imagery over the Korean peninsular for the generation of 1:25,000 scale cartographic maps. For this mission, research is being carried out to assess the possibilities of automated or semi-automated mapping of EOC data and to develop, if necessary, such enabling tools. This paper discusses the issue of automated digital elevation model (DEM) generation from EOC data and identifies some important aspects in developing a DEM generation system from EOC data. This paper also presents the current status of the development work for such a system. The development work will be described in three pares of sensor modelling, stereo matching and DEM interpolation. The performance of the system is shown with a SPOT stereo pair. A DEM generated from commercial software is also presented for comparison. The proposed system seems to generate promising results.

Mechanical and thermodynamic stability, structural, electronics and magnetic properties of new ternary thorium-phosphide silicides ThSixP1-x: First-principles investigation and prospects for clean nuclear energy applications

  • Siddique, Muhammad;Iqbal, Azmat;Rahman, Amin Ur;Azam, Sikander;Zada, Zeshan;Talat, Nazia
    • Nuclear Engineering and Technology
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    • v.53 no.2
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    • pp.592-602
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    • 2021
  • Thorium compounds have attracted immense scientific and technological attention with regard to both fundamental and practical implications, owing to unique chemical and physical properties like high melting point, high density and thermal conductivity. Hereby, we investigate the mechanical and thermodynamic stability and report on the structural, electronic and magnetic properties of new silicon-doped cubic ternary thorium phosphides ThSixP1-x (x = 0, 0.25, 0.5, 0.75 and 1). The first-principles density functional theory procedure was adopted within full-potential linearized augmented plane wave (FP-LAPW) method. The exchange and correlation potential terms were treated within Generalized-Gradient-Approximation functional modified by Perdew-Burke-Ernzerrhof parameterizations. The proposed compounds showed mechanical and thermodynamic stable structure and hence can be synthesized experimentally. The calculated lattice parameters, bulk modulus, total energy, density of states, electronic band structure and spin magnetic moments of the compounds revealed considerable correlation to the Si substitution for P and the relative Si/P doping concentration. The electronic and magnetic properties of the doped compounds rendered them non-magnetic but metallic in nature. The main orbital contribution to the Fermi level arises from the hybridization of Th(6d+5f) and (Si+P)3p states. Reported results may have potential implications with regard to both fundamental point of view and technological prospects such as fuel materials for clean nuclear energy.