• 제목/요약/키워드: State reconstruction

검색결과 275건 처리시간 0.031초

Three-Dimensional Television using Optical Scanning Holography

  • Poon, Ting-Chung
    • Journal of Information Display
    • /
    • 제3권3호
    • /
    • pp.12-16
    • /
    • 2002
  • We first review a real-time three-dimensional (3-D) holographic recording technique called optical scanning holography (OSH) and discuss holographic reconstruction using spatial light modulators (SLMs). We then present how the overall system can be used for 3-D holographic television (TV) display with a wide-angle view of a 3-D image, and address some of the issues encountered. Finally, we suggest some techniques to alleviate the issues encountered in such a 3-D holographic TV system.

정보데이터의 복원기법 응용한 실시간 하드웨어 신경망 (Realtime Hardware Neural Networks using Interpolation Techniques of Information Data)

  • 김종만;김원섭
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2007년도 추계학술대회 논문집
    • /
    • pp.506-507
    • /
    • 2007
  • Lateral Information Propagation Neural Networks (LIPN) is proposed for on-line interpolation. The proposed neural network technique is the real time computation method through the inter-node diffusion. In the network, a node corresponds to a state in the quantized input space. Through several simulation experiments, real time reconstruction of the nonlinear image information is processed.

  • PDF

상전류 센서없는 3상 PWM 3상 정류기의 전류제어 (Current Control of Three-Phase PWM Rectifiers without Phase Current Sensors)

  • 임대식;이동춘
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
    • /
    • 제49권2호
    • /
    • pp.123-129
    • /
    • 2000
  • This paper proposes a novel current control method of three-phase PWM rectifiers using estimated currents without phase current sensors. The phase currents are reconstructed from switching states of the rectifier and the measured dc output currents. To eliminate the calculation time delay effect of the microprosessor, the current at the next sampling instant are predicted by a predictive state observer and then are used for feedback control. Experimental results show that the control performance of the proposed system is almost the same as that of the phase current sensor-based system.

  • PDF

A comprehensive study on active Lamb wave-based damage identification for plate-type structures

  • Wang, Zijian;Qiao, Pizhong;Shi, Binkai
    • Smart Structures and Systems
    • /
    • 제20권6호
    • /
    • pp.759-767
    • /
    • 2017
  • Wear and aging associated damage is a severe problem for safety and maintenance of engineering structures. To acquire structural operational state and provide warning about different types of damage, research on damage identification has gained increasing popularity in recent years. Among various damage identification methods, the Lamb wave-based methods have shown promising suitability and potential for damage identification of plate-type structures. In this paper, a comprehensive study was presented to elaborate four remarkable aspects regarding the Lamb wave-based damage identification method for plate-type structures, including wave velocity, signal denoising, image reconstruction, and sensor layout. Conclusions and path forward were summarized and classified serving as a starting point for research and application in this area.

Lightweight Attention-Guided Network with Frequency Domain Reconstruction for High Dynamic Range Image Fusion

  • 박재현;이근택;조남익
    • 한국방송∙미디어공학회:학술대회논문집
    • /
    • 한국방송∙미디어공학회 2022년도 하계학술대회
    • /
    • pp.205-208
    • /
    • 2022
  • Multi-exposure high dynamic range (HDR) image reconstruction, the task of reconstructing an HDR image from multiple low dynamic range (LDR) images in a dynamic scene, often produces ghosting artifacts caused by camera motion and moving objects and also cannot deal with washed-out regions due to over or under-exposures. While there has been many deep-learning-based methods with motion estimation to alleviate these problems, they still have limitations for severely moving scenes. They also require large parameter counts, especially in the case of state-of-the-art methods that employ attention modules. To address these issues, we propose a frequency domain approach based on the idea that the transform domain coefficients inherently involve the global information from whole image pixels to cope with large motions. Specifically we adopt Residual Fast Fourier Transform (RFFT) blocks, which allows for global interactions of pixels. Moreover, we also employ Depthwise Overparametrized convolution (DO-conv) blocks, a convolution in which each input channel is convolved with its own 2D kernel, for faster convergence and performance gains. We call this LFFNet (Lightweight Frequency Fusion Network), and experiments on the benchmarks show reduced ghosting artifacts and improved performance up to 0.6dB tonemapped PSNR compared to recent state-of-the-art methods. Our architecture also requires fewer parameters and converges faster in training.

  • PDF

남아 있는 인대를 보존하고 신선 동결 동종 아킬레스건을 이용한 후방십자인대 재건술 (Posterior cruciate ligament reconstruction using fresh-frozen Achilles tendon allograft with preservation of ligament remnant)

  • 김영진;채수욱;김종윤;김병수
    • 대한정형외과스포츠의학회지
    • /
    • 제10권2호
    • /
    • pp.54-60
    • /
    • 2011
  • 목적: 슬관절의 후방십자인대 파열시 잔존하는 절단단 또는 이완된 인대를 유지하면서 신선 동결 동종 아킬레스건을 이용하여 재건술을 시행한 결과를 후향적으로 분석해 보고자 하였다. 대상 및 방법: 2004년 10월부터 2010년 3월까지 후방십자인대 완전 파열로 진단되어서 동종 아킬레스건을 이용한 재건술을 시행한 환자 중에서 최소 1년 이상 추시가 가능하였던 22례를 대상으로 하였다. 평균 추시는 3년 7개월(1년~6년 4개월)이었다. 수술시 연령은 평균 31.5세 이었으며, 성별은 남자가 14례, 여자가 8례였다. 운동 가능 범위, 후방 전위 검사, Telos stress 방사선 검사, Lysholm knee score, Tegner activity score, International Knee Documentation Commiittee (IKDC)의 판정 기준을 이용하여서 술 후 기능 평가, 2차적 관절경 검사 등을 시행하여 주관적 및 객관적 지표로 삼았다. 결과: 슬관절 안정성에 대한 이학적 검사인 후방 전위 검사, 최종 추시 시에 후방 스트레스 방사선 사진, Lysholm knee score, Tegner activity score, IKDC score 등은 통계학적 의의가 있는 좋은 결과를 보였다. 결론: 후방십자인대 파열시 잔존하는 인대의 절단단 또는 이완된 인대를 유지하면서 신선 동결 동종 아킬레스건을 이용한 재건술은 양호한 슬관절의 안정성과 기능 회복을 얻을수 있는 좋은 수술 방법으로 사료된다.

  • PDF

Complex oncologic resection and reconstruction of the scalp: Predictors of morbidity and mortality

  • Tecce, Michael G.;Othman, Sammy;Mauch, Jaclyn T.;Nathan, Shelby;Tilahun, Estifanos;Broach, Robyn B.;Azoury, Said C.;Kovach, Stephen J.
    • 대한두개안면성형외과학회지
    • /
    • 제21권4호
    • /
    • pp.229-236
    • /
    • 2020
  • Background: Oncologic resection of the scalp confers several obstacles to the reconstructive surgeon dependent upon patient-specific and wound-specific factors. We aim to describe our experiences with various reconstructive methods, and delineate risk factors for coverage failure and complications in the setting of scalp reconstruction. Methods: A retrospective chart review was conducted, examining patients who underwent resection of fungating scalp tumors with subsequent soft-tissue reconstruction from 2003 to 2019. Patient demographics, wound and oncologic characteristics, treatment modalities, and outcomes were recorded and analyzed. Results: A total of 189 patients were appropriate for inclusion, undergoing a range of reconstructive methods from skin grafting to free flaps. Thirty-three patients (17.5%) underwent preoperative radiation. In all, 48 patients (25.4%) suffered wound site complications, 25 (13.2%) underwent reoperation, and 47 (24.9%) suffered from mortality. Preoperative radiation therapy was an independent risk factor for wound complications (odds ratio [OR], 2.85; 95% confidence interval [CI], 1.1-7.3; p=0.028) and reoperations (OR, 4.45; 95% CI, 1.5-13.2; p=0.007). Similarly, the presence of an underlying titanium mesh was an independent predictor of wound complications (OR, 2.49; 95% CI, 1.1-5.6; p=0.029) and reoperations (OR, 3.40; 95% CI, 1.2-9.7; p=0.020). Both immunosuppressed status (OR, 2.88; 95% CI, 1.2-7.1; p=0.021) and preoperative radiation therapy (OR, 3.34; 95% CI, 1.2-9.7; p=0.022) were risk factors for mortality. Conclusion: Both preoperative radiation and the presence of underlying titanium mesh are independent risk factors for wound site complications and increased reoperation rates following oncologic resection and reconstruction of the scalp. Additionally, preoperative radiation, along with an immunosuppressed state, may predict patient mortality following scalp resection and reconstruction.

고령의 당뇨병성 족부 궤양의 전외측 대퇴 천공지 유리 피판술을 이용한 치료 (Management of the Diabetic Foot Ulcer in Elderly Patients Using the Anterolateral Thigh Perforator Free Flap)

  • 김재영;이인묵;나상은
    • 대한족부족관절학회지
    • /
    • 제12권1호
    • /
    • pp.59-65
    • /
    • 2008
  • Purpose: To evaluate the results of anterolateral thigh perforator free flap for reconstruction of foot and ankle in old diabetic patients. Materials and Methods: Fifteen diabetic foot ulcer patients over the age of 55 were operated with anterolateral thigh perforator free flap. Hematological, hemodynamic, diabetic, bacteriologic and radiologic tests were checked with examination of blood vessel state in both the donor site and the recipient site. After surgery, serial check-up was performed at 6 week, 6 month, and 1 year postoperatively on the survival of transplantation tissue, condition of foot, and condition of walking. Results: There are one case of transplantation failure and four cases of partial tissue-necrosis. Delayed wound-healing was observed both recipient and donor tissue sites. At the final follow up, three cases of small ulcer were found at junction of flap and recipient tissue in plantar area. Fourteen out of fifteen patients could walk without any brace or walking aids. Conclusion: Reconstruction of foot and ankle region in old diabetic patients with the anterolateral thigh perforator free flap is a useful method which can prevent the amputation of foot and ankle.

  • PDF

불량애자 검출을 위한 비젼 기반 전파 신경망 (Propagation Neural Networks based on vision techniques for detecting of Faulty Insulator)

  • 김종만;김영민;황종선;박현철;임성호
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
    • /
    • pp.1097-1102
    • /
    • 2002
  • For detecting of Faulty Insulator, a new Lateral Information Propagation Networks (LIPN) has been proposed. Energized insulator is reduced the rate of insulation extremely, and taken the results dirty and injured. It is necessary to be actions that detect the faulty insulator and exchange the new one. And thus, we have designed the LIPN to be detected that insulators by the real time computation method through the inter-node diffusion. In the network, a node corresponds to a state in the quantized input space. Each node is composed of a processing unit and fixed weights from its neighbor nodes as well as its input terminal. Information propagates among neighbor nodes laterally and inter-node interpolation is achieved. Through several simulation experiments,real time reconstruction of the nonlinear image information is processed.

  • PDF

International Congress on Electron Tomography에 대한 간략한 이해와 현황 (A Glance of Electron Tomography through 4th International Congress on Electron Tomography)

  • 유임주;박승남
    • Applied Microscopy
    • /
    • 제38권3호
    • /
    • pp.275-278
    • /
    • 2008
  • Electron tomography (ET) is an electron microscopic technique for obtaining a 3-D image from any electron microscopy specimen and its application in biomedical science has been increased thanks to development of electron microscopy and related technologies during the last decade. There are few researches on ET in Korea during this period. Although the importance of ET has been recognized recently by many researchers, initial approach to electron tomographic research is not easy for beginners. The 4th International Congress on Electron Tomography (4 ICET) was held on Nov $5{\sim}8$, 2006, at San Diego. The program dealt instrumentation, reconstruction algorithm, visualization/quantitative analysis and electron tomographic presentation of biological specimen and nano particles. 1 have summarized oral presentations and analyzed the posters presented on the meeting. Cryo-electron microscopic system was popular system for ET and followed conventional transmission electron microscopic system. Cultured cell line and tissue were most popular specimens analyzed and microorganisms including bacteria and virus also constituted important specimens. This analysis provides a current state of art in ET research and a guide line for practical application of ET and further research strategies.