• The Transactions of the Korean Institute of Power Electronics
• /
• v.4 no.5
• /
• pp.455-461
• /
• 1999

In this paper, we present the 3DOF force-rei1ecting interface which allows to acquire force of objc'Ct within a a virtual environment. This system is comlxlsed of device, virtual environment model, and force-rei1ecting r rendering algorithm. We design a J DOF force reflecting device using the pc$\alpha$allel linkage, torque shared by W wire, and the controller of system applied by impedance control algorithm. The force reflecting behaviour i implemented as a function position is equivalent to controlling the mechanical impedance felt by the user. E Especially how force should be supplied to user, we know using a God-Object algorithm As we experiment a system implement$\varepsilon$d by the interface of 3D virtual object and 3DOF force reJll'Cting i interface, we can feel a contact, non contact of :)D virtual object surface and sensin앙 of push button model.utton model.

• The Journal of Korean Society for Radiation Therapy
• /
• v.27 no.1
• /
• pp.53-60
• /
• 2015

Purpose : The purpose of this study is to evaluate the usefulness of a 3D printed phantom for in-vivo dosimetry of a prostate cancer patient. Materials and Methods : The phantom is produced to equally describe prostate and rectum based on a 3D volume contour of an actual prostate cancer patient who is treated in Asan Medical Center by using a 3D printer (3D EDISON+, Lokit, Korea). CT(Computed tomography) images of phantom are aquired by computed tomography (Lightspeed CT, GE, USA). By using treatment planning system (Eclipse version 10.0, Varian, USA), treatment planning is established after volume of a prostate cancer patient is compared with volume of the phantom. MOSFET(Metal OXIDE Silicon Field Effect Transistor) is estimated to identify precision and is located in 4 measuring points (bladder, prostate, rectal anterior wall and rectal posterior wall) to analyzed treatment planning and measured value. Results : Prostate volume and rectum volume of prostate cancer patient represent 30.61 cc and 51.19 cc respectively. In case of a phantom, prostate volume and rectum volume represent 31.12 cc and 53.52 cc respectively. A variation of volume between a prostate cancer patient and a phantom is less than 3%. Precision of MOSFET represents less than 3%. It indicates linearity and correlation coefficient indicates from 0.99 ~ 1.00 depending on dose variation. Each accuracy of bladder, prostate, rectal anterior wall and rectal posterior wall represent 1.4%, 2.6%, 3.7% and 1.5% respectively. In- vivo dosimetry represents entirely less than 5% considering precision of MOSFET. Conclusion : By using a 3D printer, possibility of phantom production based on prostate is verified precision within 3%. effectiveness of In-vivo dosimetry is confirmed from a phantom which is produced by a 3D printer. In-vivo dosimetry is evaluated entirely less than 5% considering precision of MOSFET. Therefore, This study is confirmed the usefulness of a 3D printed phantom for in-vivo dosimetry of a prostate cancer patient. It is necessary to additional phantom production by a 3D printer and In-vivo dosimetry for other organs of patient.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.1921-1924
• /
• 2005

In this paper, three-dimensional finite element analysis have been performed to investigate the biomechanics of vertebroplasty in patient. In order to apply various properties of the spine, the functional relation between the well-known apparent density and HU(Hounsfield unit) from CT image were employed and thus real material property can be assigned to each element of FE model. The FE analysis showed similar results with the experiments. With this approach accurate analysis of the spine and the clinical application can be expected.

• Electronics and Telecommunications Trends
• /
• v.24 no.2
• /
• pp.43-55
• /
• 2009

창조경제시대로 접어들면서 각국은 소프트웨어 지식산업에 눈을 돌리기 시작했으며, 대표적인 분야로 문화콘텐츠 산업을 주목하고 있다 우리나라도 문화콘텐츠 5대 강국으로의 도약을 위해 콘텐츠 분야를 17개 신성장동력 산업 중의 하나로 포함시켜 산업육성 및 CT R&D 전략을 수립하고 있다. 국내 문화콘텐츠 산업은 연평균 증가율 약 7.1%로 성장, 2012년 약 100조 원을 달성할 것으로 전망되며, IT의 뒤를 이어 신시장 개척과 기존 산업의 고부가가치화를 실현하고 국민의 삶의 질 향상 등 사회복지 증진에도 기여할 것으로 예상된다. 따라서 정책을 수립하고 시행함에 있어 OSMU등 문화 콘텐츠의 특성을 고려하고 가치사슬 주체별로 차별화하여 성과확산을 극대화시켜야 할 것이다. 또한 문화콘텐츠 비전을 됫받침하는 창조 협력 경쟁의 정책철학 및 추진체계인 "3CTP 전략'을 통해 산업 및 기술 경쟁력을 강화시켜야 할 것이다.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.5 no.3
• /
• pp.31-39
• /
• 1996

The objective of this study is to investigate the influence of welding residual stresses on the fatigue crack growth behavior of cracks located transverse to the weld bead. For this purpose, G. T. A (Gas Tungsten Arc) welding was performed on hte Al alloy 1100-O plate and the same initial crack is made on HAZ(Heat Affected Zone), weld metal and base meta respectively. Specimens were used CT(Compact Tension) specimens. Initial welding residual stresses were measured by using strai gage sectioning method. All specimens were tested under constant amplitude load with stress ratio R=0.1, It is possible to predict fatigue crack growth behaviors and the fatigue life, using numerical analysis together with distribution of initial residual stress and the values of C and m obtained from $da/dN-{\Delta}K$

• Proceedings of the KACD Conference
• /
• 2001.11a
• /
• pp.558.2-558
• /
• 2001

The aims of this study are (1) to investigate the relation of irradiation mode, polymerization shrinkage and degree of cure of composite resin and(2) it effect on micorleakage of class V restorations. VIP(BISCO Dental Products, Schaumburg, IL, USA) and Optilux 501 (Demetron/Kerr, Danbury, CT, USA) curing lights were used for curing Z-250 composite resin following irradiation mode: VIP 200㎽d, VIP 400㎽, VIP 600㎽, pulse-delay(200㎽ 3sec, 5min wait, 600㎽ 30sec), Optilux R mode.(omitted)

• Proceedings of the KOSOMBE Conference
• /
• v.1998 no.11
• /
• pp.113-114
• /
• 1998

In this paper, visualization of Visible Human data offered by NLM(National Library of Medicine) is performed using $VTK^{TM}$. Computed Tomography Data set(axial, $587\times341\times256$, and the distance between slices 1mm) is used throughout the study. Before the actual visualization routine, 8 bit-reader class of VTK is developed to transform CT data to VTK dataset. After that, the visualization procedures are done to display 3D image on PC. VTK is freeware, not a commercial software. The results of VTK show relatively good image quality and slower processing time compared with the commercial softwares like IAP, IDL, AVS. Thus if processing time is not the critical factor, VTK is worthy to be used in visualization of the medical images.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2006.05a
• /
• pp.171-172
• /
• 2006

Most existing studies for stress analysis of teeth have employed small number of teeth, and used big element size using F-E models. Therefore, the results are not accuracy enough for showing the internal stress variation. 15 males' and 13 females' mandibular first premolar are employed for internal structure's study of teeth and small element size for a FE model are used. According to these processes, stress distribution of internal parts of teeth are well shown, and the stresses are varied a lot between enamel layer and dentine layer, but there is little variation on pulp chamber.

• Electronics and Telecommunications Trends
• /
• v.26 no.2
• /
• pp.126-136
• /
• 2011

최근 문화기술(CT) 기반으로 다양한 산업의 콘텐츠화가 급속히 진행되고 있는 가운데, 융합형 콘텐츠가 새로운 성장동력으로서 주목받고 있다. 또한 상상력과 창의력 기반의 문화적 요소가 가미된 융합형 콘텐츠 산업은 '경쟁없는 시장'으로서 국가 비즈니스 혁신의 돌파구가 될 것으로 전망되고 있다. 이런 상황에서 차세대 융합형 콘텐츠 분야의 유망 전략 산업에 대한 산업-기술 연계 로드맵 작성 및 기술기획 프레임워크(framework) 구축은 미래 기술기획 및 기술개발, 관련 산업의 활성화, R&D 투자 배분 등을 위한 사전 작업 및 방향지표로서의 의의를 가진다. 이에 본 고에서는 유망 융합형 콘텐츠 분야에 대한 산업-기술 연계 로드맵을 3가지 기술발전 경로, 즉 단위 소요기술의 향상(upgrade road), 기존 소요기술의 진화(evolution road), 단위 소요기술의 혁신(innovation road)을 반영하여 작성하는 입체로드맵으로 기술기획 프레임워크 내에서 제시 적용하도록 한다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2009.10a
• /
• pp.329-332
• /
• 2009

Speckle noise reduction for ultrasound CT image using morphological adaptive median filtering based on edge preservation is presented in this paper. Speckle noise is multiplicative feature and causes ultrasound image to degrade widely from transducer. An input image is classified into edge region and homogeneous region in preprocessing. The speckle is reduced by morphological operation on the 2D gray scale by using convolution and correlation, and edges are preserved. The adaptive median is processed to reduce an impulse noise. As the result the proposed method enhances the image to about 20% in comparison with Winer filter by Edge Preservation Index and PSNR.