• 스마트미디어저널
• /
• 제4권4호
• /
• pp.64-69
• /
• 2015

본 논문에서는 UWB 통신 시스템의 테이퍼드 슬롯 안테나를 제안하였다. 테이퍼드 슬롯 안테나는 넓은 대역폭 특성과 진행파 안테나의 지향성 방사를 갖는다. 제안된 테이퍼드 슬롯 안테나는 Ansys사의 HFSS를 사용하여 설계하였으며, 반사손실 및 정재파비, 방사패턴 등을 분석하였다. 안테나의 동작 대역은 2.7 ~ 4.8 GHz 대역에서 -10 dB S11 및 $VSWR{\leq}2$(2.1 GHz)를 만족하였다. 안테나의 방사패턴은 E-평면(YZ plane)과 H-평면(XZ plane)에서 특정한 방향으로 신호를 전송하는 지향성 방사패턴을 보였으며, 이득은 4.5 GHz 대역에서 7.3 dBi의 높은 이득을 보였다. 따라서 제안된 테이퍼드 슬롯 안테나는 넓은 대역폭 특성과 위치인식에 적합한 지향성의 특성을 보인다.

• 한국광학회지
• /
• 제13권3호
• /
• pp.182-188
• /
• 2002

위상이동 간섭무늬 투영 방법을 이용한 3차원 형상측정 시스템의 위상계산오차를 분석하였다. 본 연구에서 다룬 오차의 요소에는 물체 표면의 특성에 따라 검출기에 나타나는 양자화 크기의 변이 효과, 물체 표면에 맺히는 간섭무늬 패턴의 초점 어긋남 효과, 간섭무늬의 위상이동 오차에 의한 효과, 위상 이동된 간섭무늬 패턴이 투영된 여러 개의 물체 상을 받아들이는 도중에 시스템 및 주위 환경 변화에 의한 오차, 그리고 투영되는 격자 패턴의 왜곡에 의한 효과들을 계산하고 논의하였다.

• 패션비즈니스
• /
• 제17권3호
• /
• pp.30-47
• /
• 2013

In the modern fashion industry, efficiency has been increasing thanks to development of computer graphics, IT technology, and digitalization. Unlike the past when fashion design heavily depended on handwork, digitalization of fashion industry makes fabrication time shorter and enables designers to adopt comprehensive expression, generating high value-added product. The Apparel CAD, an example of the digitalized fashion industry, has been developed from 2D system into a system providing 3D simulation. Digital clothing can be determined as an activity of designers using the tool in order to fabricate pattern and simulate its designed clothes in the virtual space of computer. In this study, physical properties of eight materials, which can be utilized on a par with current fashion trend, have been specified. For more sophisticated investigation, external appearance of the material was investigated by 3D scanning. In order to examine the physical properties of fabric specimens, KES(Kawabata Evaluation System) measurements and other physical property measurements were made. With the results, virtual material and clothes were simulated via CLO 3D, one of 3D apparel CAD systems. Then, virtual fabrics and clothes of similar types were generated and analyzed.

• 제어로봇시스템학회논문지
• /
• 제19권12호
• /
• pp.1067-1071
• /
• 2013

A 3D visual sensing method using a laser structured beam is presented for robotic tracking applications in a simple and reliable manner. A cylindrical shaped laser structured beam is proposed to measure the pose and position of the target surface. When the proposed laser beam intersects on the surface along the target trajectory, an elliptic pattern is generated. Its ellipse parameters can be induced mathematically by the geometrical relationship of the sensor coordinate and target coordinate. The depth and orientation of the target surface are directly determined by the ellipse parameters. In particular, two discontinuous points on the ellipse pattern, induced by seam trajectory, indicate mathematically the 3D direction for robotic tracking. To investigate the performance of this method, experiments with a 6 axis robot system are conducted on two different types of seam trajectories. The results show that this method is very suitable for robot seam tracking applications due to its excellence in accuracy and efficiency.

• 한국CDE학회논문집
• /
• 제5권2호
• /
• pp.136-143
• /
• 2000

The appearance of new machine tools with higher flexibility is in need of a basic structure design system for establishing the systematic and rationalized design and manufacturing procedures. In this study. the basic structure design system for machine tools is realized based on the modular construction method. Machine tools are represented as a whole and modular complex with the directed graph, and all possible structural configurations and codes of machine tools for satisfying the machining requirement are derived from the DNA data and connecting patterns of basic structural elements. Especially the structural configurations of machine tools are visualized by the solid modeling techniques and 3-D graphics techniques.

• 패션비즈니스
• /
• 제26권5호
• /
• pp.91-104
• /
• 2022

In this study, a cycling smart wear for measuring cycling posture and motion was developed using a three-dimensional motion analysis camera and an IMU inertial sensor. Results were compared according to parts to derive the optimal smart device attachment location, enabling correct posture measurement and cycle motion analysis to design a pattern. Conclusions were as follows: 1) 'S-T8' > 'S-T10' > 'S-L4' was the most significant area for each lumbar spine using a 3D motion analysis system with representative posture change (90°, 60°, 30°) to derive incisions and size specifications; 2) the part with the smallest relative angle change among significant section reference points during pattern design was applied as a reference point for attaching a cycling smart device to secure detachable safety of the device. Optimal locations for attaching the cycling device were the "S-L4" hip bone (Sacrum) and lumbar spine No. 4 (Lumbar 4^th); 3) the most suitable sensor attachment location for monitoring knee induction-abduction was the anatomical location of the rectus femoris; 4) a cycling smart wear pattern was developed without incision in the part where the sensor and electrode passed. The wearing was confirmed with 3D CLO. This study aims to provide basic research on exercise analysis smart wear, to expand the smart cycling area that could only be realized with smart devices and smart watches attached to current cycles, and to provide an opportunity to commercialize it as cycling smart wear.

• 대한치과보철학회지
• /
• 제41권4호
• /
• pp.421-439
• /
• 2003

Statement of problem : It is difficult to obtain a good titanium casting body using the traditional sprue design because of high melting point of Ti, and the low fluidity and high reactivity of molten Ti. Purpose : A new sprue design for titanium casting bodies needs more trial and error. In order to decrease the number of trial and error, computer simulation(MAGMASOFT, Magmasoft Giessereitechnologie GmbH, Achen, Germany) was used to optimize sprue design in U-shaped implant superstructures. Material and method : Five kinds of sprue were examined for the design of the sprue former for titanium casting: Sprue design A(sprue length 4 mm, rectangular shape, 4 sprues), Sprue design B(sprue length 4 mm. round shape. radius 2 mm, 7 sprues), Sprue design C (sprue length 2 mm, round shape, radius 2 mm, 7 sprues). Sprue design D (sprue length 2 mm, cone shape, large radius 3mm. small radius 2mm, 7 sprues), and Sprue design E( sprue length 2 mm. one unit channel shape). Sprue design F(sprue length 2mm, one unit channel shape) was also examined for the design of the customized sprue former in the Biotan system(Schutz Dental Gmbh, Germany). The casting bodies were taken in Sprue design A, Sprue design D, Sprue design E, and Sprue design F in the Biotan casting system. The numerically predicted defects were compared with the experimental dental castings by the radiographic and sectional view observations. Results : 1. According to the result of computer simulation, turbulence during mold filling was decreased in the sequence of Sprue design F, Sprue design E, Sprue design D, Sprue design C, Sprue design B, and Sprue design A. 2. The calculated solidification time contours indicate that hot spot was moved from the casting body to the sprue button in the sequence of Sprue design A, Sprue design B, Sprue design C, Sprue design D, and Sprue design E. The filling pattern of Sprue design F was similar to that of Sprue design E. 3 The predicted filling pattern shows that less turbulence was found in the customized sprue former than in the standard sprue former. 4. According to the results of the radiographic and cross sectional observations, casting defects less than 1mm were found at the center of a casting body with Sprue design E and Sprue design F. However, larger casting defects of 4mm were found in a casting with Sprue design A. 5. The predicted casting porosity was similar to that of the real casting. Conclusion : One unit channel-type and customized sprue former can be recommended. Further research and developement of various sprue designs using computer simulation in necessary to optimize casting design, in order to reduce the formation of casting defects in implant titanuim super-structures.

• 한국군사과학기술학회지
• /
• 제17권1호
• /
• pp.90-95
• /
• 2014

The system design and the system performance analysis of 3D imaging laser radar system for the mapping purpose is addressed in this article. For the mapping, a push-bloom scanning method is utilized. The pulsed fiber laser with high pulse energy and high pulse repetition rate is used for the light source of laser radar system. The high sensitive linear mode InGaAs avalanche photo-diode is used for the laser receiver module. The time-of-flight of laser pulse from the laser to the receiver is calculated by using high speed FPGA based signal processing board. To reduce the walk error of laser pulse regardless of the intensity differences between pulses, the time of flight is measured from peak to peak of laser pulses. To get 3D image with a single pixel detector, Risley scanner which stirs the laser beam in an ellipsoidal pattern is used. The system laser energy budget characteristics is modeled using LADAR equation, from which the system performances such as the pulse detection probability, false alarm and etc. are analyzed and predicted. The test results of the system performances are acquired and compared with the predicted system performance. According to test results, all the system requirements are satisfied. The 3D image which was acquired by using the laser radar system is also presented in this article.

• 디자인학연구
• /
• 제14권3호
• /
• pp.77-85
• /
• 2001

본 논문은 아이디어 전개를 종합(synthesis)에 의해 처리되는 디자인 업무의 중심부분으로, 자시 말하면, 디자인 문제에 대한 발상(abduction)과 변환(transformation)이 야기되는 부분으로 보고, 이에 대한 창조적 디자인 사고의 형식을 밝히고, 이를 토대로 디자인 발상지원 시스템의 기초를 마련하는 데 이 연구의 목표가 있다 연구방법으로 디자인 사고에 대한 고찰을 토대로 디자인 사고(design thinking)의 모형을 설정하고, 디자인 직무분석(job analysis)으로 이 연구모형을 검토하여 디자인 사고의 형식과 그 구조를 밝히는 것이다. 창조적 디자인사고의 전개는 디자인 문제해결에서 새롭고 유용한 착상을 이루어 가는 과정으로서 발산(Divergence)/변형(Transformation)/수렴(Convergence)의 과정을 가지며, 추상적 개념으로부터 시작하여 구체적인 결과에 도달한다. 디자인 프로세스에서 아이디어 스케치와 같은 디자인 전개의 직무는 D-T-C 발상이 집중되는 직무군으로 난이도가 비교적 높은 것으로 나타났다. D-T-C 발상의 추상-구체의 조합적 전개가 가능하도록 직무분석에 의해 디자인 발상지원 시스템(Computer Mediated Creative Thinking System: CMCTS)을 설계하였다.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2006년도 영호남 합동 학술대회 및 춘계학술대회 논문집 센서 박막 기술교육
• /
• pp.77-81
• /
• 2006

We report the performance of a four-element, 11.67 GHz, high-Tc superconducting (HTS) microstrip antenna array with corporate feed network and circular polarization for direct broadcasting satellite (DBS) system. Our array antennas were designed and built on a 0.5 mm thick MgO substrate. To compare the superconducting antennas with normal conducting counterpart, One antenna pattern was fabricated from gold thin film, and a second pattern was fabricated from $YBa_2Cu_3O_{7-x}$ (YBCO) superconducting thin film. To improve the axial ratio of circularly polarized arrays, sequential rotation technique were used. Efficiency, radiation pattern, return loss and bandwidth were measured for both antennas at room temperature and at cryogenic temperature. The array produced good circular polarization, and the gain of the array at 77 K, relative to a copper array at room temperature was approximately 1.54 dB. The measured return loss of our HTS antenna array was 35.79 dB at the resonant frequency of 11.67 GHz and The total effective bandwidth was about 3.4 %. The results showed that high-temperature superconductors, when used in microstrip arrays, improved the efficiency of the HTS antenna array for circularly polarization.