• 제목/요약/키워드: 3D Point Data

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수치영상을 이용한 사면지반 계측시스템 개발(1) - 캐드의 연계를 통한 DCRP 교육용 운용시스템 구축 - (The Construction of Digital Close Range Photogrammetry System Integrated With CAD for Education)

  • 배상호;주영은
    • 한국측량학회지
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    • 제20권4호
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    • pp.399-404
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    • 2002
  • 본 연구에서는 고가의 측정장비와 해석장비를 배제한 보다 경제적인 매체를 활용하여 관련 학습자가 손쉽게 사진측량을 이해하고 활용할 수 있는 솔류션을 제공하고자 하였다. 이를 위해, 모니터 상의 입체영상에 이벤트를 발생시켜 3차원 위치자료를 해석하고 캐드 시스템에 자동 입력하도록 하여 좌표측정과 함께 실시간 벡터편집 및 도면화를 가능하게 하였다. 그리고, 구축 시스템의 검증을 수행하여 실 구조물에 대한 모니터링을 수행할 수 있었으므로 관련 분야의 실습용 운용 교보재로서의 활용이 가능할 것으로 기대한다.

점군으로부터 형성된 다각곡선망을 보간하는 곡면모델링에 관한 연구 (A Study of a Surface Modeling Interpolating a Polygonal Curve Net Constructed from Scattered Points)

  • 주상윤;전차수
    • 대한산업공학회지
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    • 제21권4호
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    • pp.529-540
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    • 1995
  • The paper deals with a procedure for constructing a composite surface interpolating a polygonal curve mesh defined from 3D scattered points. The procedure consists of a poly-angulation, construction of a curve net, and interpolation of the curve net. The poly-angulation contains a stage that changes a triangular edge net obtained from a triangulation into a poly-angular edge net. A curve net is constructed by replacing edges on the edge net with cubic Bezier curves. Finally, inside of an n-sided polygon is interpolated by n subdivided triangular subpatches. The method interpolates given point data with relatively few triangular subpatches. For an n-sided polygon, our method constructs an interpolant with n subdivided triangular subpatches while the existing triangular surface modeling needs 3(n-2) subpatches. The obtained surface is composed of quartic triangular patches which are $G^1$-continuous to adjacent patches.

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6 자유도 모델에 기반한 운항중인 함정의 3차원 RCS 측정 및 분석 기법 (Measurement and Analysis for 3-D RCS of Maritime Ship based on 6-DOF Model)

  • 곽상열;정회인
    • 한국군사과학기술학회지
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    • 제21권4호
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    • pp.429-436
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    • 2018
  • The RCS value of maritime ship is indicator of ship's stealth performance and it should be particularly measured for navy ship to ensure survivability on the battlefield. In the design phase of the navy ship, a RCS prediction should be performed to reduce RCS value and achieve ROC(Required Operational Capability) of the ship through configuration control. In operational phase, the RCS value of the ship should be measured for verifying the designed value and obtaining tactical data to take action against enemy missile. During the measurement of RCS for the ship, ship motion can be affected by roll and pitch in accordance with sea state, which should be analyzed into threat elevation from view point of enemy missile. In this paper, we propose a method to measure and analyze RCS of ship in 3-dimensions using a ship motion measuring instrument and a fixed RCS measurement system. In order to verify the proposed method, we conducted a marine experiment using a test ship in sea environment and compared the measurement data with RCS prediction value which is carried by prediction SW($CornerStone^{TM}$) using CAD model of the ship.

오프셋 인쇄의 틈새출구에서 공동의 변화에 대한 시뮬레이션 (Computer Simulation for the Cavitation Changes at the Exit of Offset Printing Nip)

  • 윤종태;김윤택;임수만
    • 펄프종이기술
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    • 제46권3호
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    • pp.1-10
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    • 2014
  • Offset paper printing is a promising roll-to-roll technique for color printed materials. Although it is no doubt that understanding ink transfer mechanism in offset printing process is necessary to achieve high printing quality, investing the relationship between inks and substrates at the nip is difficult experimentally due to high printing speed. In this paper, rheological behavior and splitting point of the ink at the nip is studied using package software Ployflow and Flow 3D based on Navier-Stokes equation. Polydimethylsiloxane (PDMS) ink and IGT printability tester were used for an model ink and experiment to compare with that of simulation data, respectively. As a result, higher viscosity at state flow and pressure increased ink transfer due to higher possibility of presence of cavitation at the nip and increase in covering area ratio. These results have shown good agreements with experimental data compared by measuring density of print through.

Relationship between sonorheometry parameters and laboratory values in a critical care setting in Italy: a retrospective cohort study

  • Antonio Romanelli;Renato Gammaldi;Alessandro Calicchio;Salvatore Palmese;Antonio Siglioccolo
    • Journal of Trauma and Injury
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    • 제36권3호
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    • pp.210-216
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    • 2023
  • Purpose: This preliminary retrospective cohort study analyzed the relationship between the parameters provided by sonorheometry device Quantra and the coagulation values obtained from standard venous blood samples in patients admitted in intensive care unit (ICU). Methods: We reviewed medical charts of 13 ICU adult patients in whom at least one coagulation study with Quantra was performed. The relationship between Quantra and laboratory data was analyzed with the Spearman rank correlation coefficient (rho). The 95% confidence interval (CI) was computed. A P-value <0.05 was considered statistically significant. Results: We collected 28 data pairs. Statistically significant moderate correlations were found for the following parameters: clot time (CT) and activated partial thromboplastin time (rho=0.516; 95% CI, 0.123-0.904; P=0.009; clot stiffness (CS) and the international normalized ratio (INR; rho=0.418; 95% CI, 0.042-0.787; P=0.039); INR and platelet contribution to CS (rho=0.459; 95% CI, 0.077-0.836; P=0.022); platelet count and platelet contribution to CS (PCS; rho=0.498; 95% CI, 0.166-0.825; P=0.008); and fibrinogen and fibrinogen contribution to CS (FCS; rho=0.620; 95% CI, 0.081-0.881; P=0.001). Conclusions: Quantra can provide useful information regarding coagulation status, showing modest correlations with the parameters obtained from laboratory tests. During diffuse bleeding, CT and FCS values can guide the proper administration of clotting factors and fibrinogens. However, the correlation of INR with CS and PCS can cause misinterpretation. Further studies are needed to clarify the relationship between Quantra parameters and laboratory tests in the critical care setting and the role of sonorheometry in guiding targeted therapies and improving outcomes.

다중처리 구조를 갖는 초음파 의료영상 전송용 ISDN(Integrated Services Digital Network) TA(Terminal Adaptor) 구현에 관한 연구 (A Study on the Implementation of the Multi-Process Structured ISDN Terminal Adaptor for Sending the Ultra Sound Medical Images)

  • 남상규;이영후
    • 대한의용생체공학회:의공학회지
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    • 제15권3호
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    • pp.317-324
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    • 1994
  • 본 논문에서는 ISDN(Intergrated Services Digital Network) LAPD(Link Access Procedure on the D-channel)와 LAPB(Link Access Procedunre on the B-channel) 프로토콜 구현과 비 ISDN 기기 용 ISDN 접속장치인 TA(Terminal Adaptor)를 위한 새로운 방법을 제안하였다. 본 논문에서 제안한 방법은 지금까지의 방법과는 달리 실시간 운영체제의 커널부를 타켓보드(target board)에 이식하여 ISDN LAPD와 LAPB 프로토콜을 구현하는 것이다. 구현된 시스템의 특징은 첫째, 각 계층에서 발생한 프로세스들을 병렬적(Multi Tasking)으로 처리하도록 하였고, 둘째, 프로토콜 구현을 위해 필요한 타이머들이 커널부로부터 소프트웨어적으로 지원되도록 하였으며, 셋째, 운영체계의 포트 함수를 응용하여 CCITT에서 권고하는 SAP(service access point)를 구현 하였다. 제안한 방법에 따라 운영체계를 이용하여 ISDN 사용자 망 인터페이스를 위한 LAPD의 계층1(layer1), 계층2(layer2) 및 계층3(Call control) 프로토콜과 LAPB프로토콜을 구현하여 모의 망 종단 장치에 연결시켜 실험을 수행한 결과 계층2(LAPD)에서의 TEI(Terminal Equipment Identifier)할당과, 다중 프레임 전송모드의 설정 후 계층3의 메세지가 전송됨을 확인하였고, 이를 이용하여 계층3에서 호설정이 이루어지고 해제되는 것을 확인 하였다. 그리고 설정된 패스를 통해 LAPB 프로토콜을 이용하여 B 채널로 데이터의 전송이 이뤄짐을 확인하였다. 따라서, 본 논문에서는 PC로부터의 초음파 의료 영상 또는 음성 정보를 ISDN환경에서 보다 효율적으로 전송할 수 있는 ISDN망에서의 전송시스템이 구현됨으로써 향후 ISDN망에 접속하여 사용할 수 있는 가능성을 확인하였다.

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희소행렬 기반 NetCDF 파일의 압축 방법 (Compressing Method of NetCDF Files Based on Sparse Matrix)

  • 최규연;허대영;황선태
    • 정보과학회 컴퓨팅의 실제 논문지
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    • 제20권11호
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    • pp.610-614
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    • 2014
  • 많은 과학 데이타처럼 화산재 확산 시뮬레이션 결과는 NetCDF 형식의 군집화된 희소행렬이다. 그리고 크기가 커서 저장과 전송에 많은 비용이 발생한다. 본 논문에서는 다차원 인덱스를 일차원으로 바꾸고 연속된 0을 그 시작점과 길이만을 기록하여 화산재 확산 시뮬레이션 데이터의 크기를 줄이는 방법을 제안한다. 이 방법은 기존의 ZIP 형식으로 압축한 것과 거의 같은 성능을 보이나 NetCDF의 구조는 손상하지 않는다. 제안된 방법에 의하면 데이터 크기가 줄어들어 저장공간의 효율이 높아지고 네트워크 전송시간이 줄어드는 효과를 기대할 수 있을 것이라 사료된다.

Research and development of haptic simulator for Dental education using Virtual reality and User motion

  • Lee, Sang-Hyun
    • International Journal of Advanced Culture Technology
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    • 제6권4호
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    • pp.52-57
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    • 2018
  • The purpose of this paper is to develop simulations that can be used for virtual education in dentistry. The virtual education to be developed will be developed with clinical training and actual case data of tooth extraction. This development goal is to allow dental students to learn the necessary surgical techniques at the point of their choice, not going into the operating room, away from time, space, and physical limits. I want to develop content using VR. Oculus Rift HMD, Optical Based Outside-in Tracking System, Oculus Touch Motion Controller, and Headset as Input / Output Device. In this configuration, the optimization method is applied convergent, and when the operation of the VR contents is performed, the content data is extracted from the interaction analysis formed in the VR engine, and the data is processed by the content algorithm. It also computes events and dental operations generated within the 3D engine programming and generates corresponding events through data processing according to the input signal. The visualization information is output to the HMD using the rendering information. In addition, the operating room environment was constructed by studying lighting and material for actual operating room environment. We applied the ratio of actual space to virtual space and the ratio between character and actual person to create a spatial composition at a similar rate to actual space.

Ethanol, 1-propanol, 2-propanol 그리고 2,2,4-trimethylpentane 이성분 혼합계에 대한 인화점 측정 (Measurement of flash point for binary mixtures of Ethanol, 1-propanol, 2-propanol and 2,2,4-trimethylpentane)

  • 황인찬;인세진
    • 청정기술
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    • 제25권2호
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    • pp.140-146
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    • 2019
  • 산업현장에서 액체의 화재 및 폭발 위험을 결정하는데 사용되는 가장 중요한 변수 중 하나인 인화점은 가연 물질에 대한 화재 위험성을 나타내는 지표이며 위험물의 안전성 평가를 위한 중요한 정보로 활용된다. 본 연구의 목적은 석유 화학 공정에서 아주 중요한 용매로 사용되는 알킬 알코올과 함께 파라핀계 탄화수소의 대표적인 화합물인 2,2,4-trimethylpentane을 포함하는 이성분 혼합물인 {ethanol + 2,2,4-trimethylpentane}, {1-propanol + 2,2,4-trimethylpentane} 그리고 {2-propanol + 2,2,4-trimethylpentane} 계에 대한 인화점을 Stanhope-Seta 밀폐식 인화점 측정기를 이용하여 측정하였다. 각 이성분계 혼합물에 대한 인화점을 예측하기 위해 Raoult's의 법칙, Wilson, NRTL 그리고 UNIQUAC 파라미터를 이용하였고 실험 결과와 비교해 보았다. 비교 결과 Raoult's의 법칙을 제외하고 모든 실험값과 예측값과 실험값은 최대 편차가 1.28 K이내의 결과로 유사함을 보였다. 또한 측정된 모든 계에서 최소인화점은 발견되지 않았다.

국내.외 브래지어의 패턴비교분석 및 착의평가 연구 (Comparative Pattern Analysis and the Fitness Evaluation of Brassieres)

  • 서추연
    • 한국의류학회지
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    • 제34권4호
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    • pp.673-685
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    • 2010
  • This study evaluates the fitness of brassieres through size measurement, comparative pattern analysis, cross section map analysis, 3-D shape analysis number, and fitness evaluation with a focus on domestic and overseas brands. Experimental brassieres were selected as mold brassieres of 3/4 cup in 75A size that is considered a popular design. Brands of selected brassiere were 2 domestic brands (A, B), 1 licensed brand (C), and 2 overseas brands (D, E). Subjects were 8 women in their early 20's. Data were analyzed by descriptive statistics, analysis of variance, reliability analysis, and factor analysis. The results were as follows; the size and pattern of brassieres showed a difference by each brand even though brassieres are the same design. In the wearing effect of brassieres, overseas brand brassieres played a major role in the breast-up effect, but they were not appropriate for the somatotype of Korean women. Domestic brand brassieres showed the volume-up effect, that was confirmed by the increasing bust circumference, bust depth when subjects wore it. In addition, the licensed brand brassieres showed the correction effect of body shape. Therefore, when purchasing a brassiere, the most important condition is to consider the individual characteristics of the somatotype. The results of factor analysis through a functional evaluation show that wearing satisfaction, size satisfaction, and the position of the bust point were important factors for fitness satisfaction and purchase.