• 제목/요약/키워드: size distortion

검색결과 419건 처리시간 0.028초

컴퓨터 단층촬영, 자기공명영상, 뇌혈관촬영을 이용한 정위적 수술시스템의 개발 (Development of Stereotactic Surgery system with CT, MR Imaging, and Angiography)

  • 김성현;서태석
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1998년도 추계학술대회
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    • pp.117-118
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    • 1998
  • The aim of this work is to develop 3-D stereotactic localization system in order to determine the precise shape, size and location of the lesion in the brain in the field of Stereotactic Radiosurgery(SRS) and neurosurgery using CT/MRI/angiography and multi-purpose QA phantom. The algorithms to obtain a 3-D stereotactic coordinates of the target have been developed, and targets on each CT image were superimposed each other on MR/angiography images without distortion corretion. This system was implented in Visual C++ as a PC-based application program.

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선삭시 미스트 발생특성에 미치는 절삭변수의 영향 (The effects of cutting parameters on the characteristics of mist generation in turning)

  • 오명석
    • 한국산업융합학회 논문집
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    • 제7권1호
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    • pp.55-62
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    • 2004
  • The presence of cutting fluid for cutting tool and workpiece leads a temperature decrease, and reduces tool wear and residual stress. Moreover, it disposes chips from cutting area, and reduces thermal distortion. However, in manufacturing, cutting fluid used in cutting process is undesirable for both human and environmental aspect. Also, it's not economic for cutting cost. This paper studied experimentally the effects of cutting parameters on the characteristics of mist generation in turning. The results of experiment are as follows: 1) The more severe cutting conditions the more mist generate, 2) The ratio of weight concentrations of cutting fluid nearly have no an effect on the amounts of mist generation 3) The size of SMD is not affected by cutting parameters.

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A Survey on Content Aware Image Resizing Methods

  • Garg, Ankit;Negi, Ashish
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제14권7호
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    • pp.2997-3017
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    • 2020
  • With the advancement in the field of image processing, images are being processed using various image processing algorithms. Nowadays, many efficient content-aware image resizing techniques are being used to safeguard the prominent regions and to generate better results that are visually appealing and pleasing while resizing. Advancements in the new display device with varying screen size demands the development of efficient image resizing algorithm. This paper presents a survey on various image retargeting methods, comparison of image retargeting results based on performance, and also exposes the main challenges in image retargeting such as content preservation of important regions, distortion minimization, and improving the efficiency of image retargeting methods. After reviewing literature from researchers it is suggested that the use of the single operator in image retargeting such as scaling, cropping, seam carving, and warping is not sufficient for obtaining satisfactory results, hence it is essential to combine multiple image retargeting operators. This survey is useful for the researchers interested in content-aware image retargeting.

Improved Transmitter Power Efficiency using Cartesian Feedback Loop Chip

  • Chong, Young-Jun;Lee, Il-Kyoo;Oh, Seung-Hyeub
    • Journal of electromagnetic engineering and science
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    • 제2권2호
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    • pp.93-99
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    • 2002
  • The Cartesian loop chip which is one of key devices in narrow-band Walky-Talky transmitter using RZ-SSB modulation method was designed and implemented with 0.35 Um CMOS technology. The reduced size and low cost of transmitter were available by the use of direct-conversion and Cartesian loop chip, which improved the power efficiency and linearity of transmitting path. In addition, low power operation was possible through CMOS technology. The performance test results of transmitter showed -23 dBc improvement of IMD level and -30 dEc below suppression of SSB characteristic in the operation of Cartesian loop chip (closed-loop). At that time, the transmitting power was about 37 dBm (5 W). The main parameters to improve the transmitting characteristic and to compensate the distortion in feed back loop such as DC-offset, loop gain and phase value are interfaced with notebook PC to be controlled with S/W.

Shrinkage Free Sintering of Low Temperature Cofired Ceramics by Glass Infilteration

  • Yeo, Dong-Hun;You, Jung-Hun;Shin, Hyo-Soon;Kim, Jong-Hee
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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    • pp.1218-1219
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    • 2006
  • The shrinkage variation of Low Temperature Cofired Ceramics(LTCC) limits the size of the substrates that impose limitations on embedded passive components. This paper focuses on the method of minimizing or controlling planar shrinkage and reducing distortion during firing. The laminated sheets of alumina and glass were sintered at varying temperature, and depending on the amount of the glass ceramics. When the sintered of multi-layer structure with $Al_2O_3/Glass/Al_2O_3$, the glass infiltrated entirely into $Al_2O_3$ layer at the temperature of about $950^{\circ}C$ or higher.

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고 복잡도 H.264/AVC의 실시간 압축을 위한 고속 인터 예측 부호화 기법 (A Fast Inter Prediction Encoding Algorithm for Real-time Compression of H.264/AVC with High Complexity)

  • 김영현;최현준;서영호;김동욱
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2006년도 하계종합학술대회
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    • pp.411-412
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    • 2006
  • In this paper, we proposed a fast algorithm for inter prediction included the most complexity in H.264/AVC. It decide search range according to direction of predicted motion vector, and then perform adaptive candidate spiral search. Simultaneously, it perform motion estimation of variable loop with threshold for variable block size. Conclusively, it is implemented in JM FME with high complexity applying to rate-distortion optimization. Experimental results show that significant complexity reduction is achieved while the degradation in video quality is negligible.

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Capillary Electrophoresis of Microbes

  • Moon, Byoung-Geoun;Lee, Yong-Ill;Kang, Seong-Ho;Kim, Yong-seong
    • Bulletin of the Korean Chemical Society
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    • 제24권1호
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    • pp.81-85
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    • 2003
  • Direct analysis of microbes such as either gram-positive or gram-negative bacteria without cell lysis was investigated using capillary electrophoresis. Bacteria cells were directly introduced into the microbore fusedsilica capillary, then separated under high electric field in less than 15 min. It was found that a proper dispersion of bacteria cells was important for reproducible results. Migration behavior of bacteria at different storage condition was investigated and many unexpected peaks were observed from bacteria stored at room temperature due to the distortion of cells. This phenomenon was attributed to the change of size and shape of the same bacterium and confirmed by the scanning electron microscopic images.

벌크헤드 플레이트가 부착된 강바닥판교의 피로상세 개선 연구 (A Study on Improvement of fatigue Details in Orthotropic Steel Deck Bridge with Bulkhead Plate)

  • 공병승
    • 한국해양공학회지
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    • 제18권1호
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    • pp.22-27
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    • 2004
  • An orthotropic steel deck system is widely adapted form for a long-span bridge. It has many advantages, such as the big reduction of dead weight, the simplicity for erection, and the reduction of the construction period. However, an orthotropic steel deck system requires a lot of welding work, which may result in defects and deformation of connection. Therefore, the research for the general behavior and fatigue strength of the several details in orthotropic steel deck bridge is necessary. The fatigue failure with distortion results from secondary stress by out-of-plane deformation; these kinds of cracks are very difficult to measure, and can not be precisely calculated through finite element analysis. This stress concentration phenomenon generates the fatigue failure around the lower scallop of the transverse rib. This paper presents improved details of the intersection between the longitudinal rib and the transverse rib of an orthotropic steel deck bridge by the third dimensional hit size test, and the finite element method, which can minimize local stress through parametric study.

새로운 정전용량 계산식물 이용한 대면적 .고화질 TFT-LCD의 화소 특성 시뮬레이션 (Simulations of Pixel Characteristics for Large Size and High Qualify TFT-LCD using a new sophisticated Capacitance Formulas)

  • 윤영준;정순신;김태형;박재우;최종선
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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    • pp.613-616
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    • 1999
  • An active-matrix LCD using thin film transistors (TFTs)has been widely recognized as having potential for high-quality color flat-panel displays. Pixel-Design Array Simulation Tool (PDAST) was used to profoundly understand the gate signal distortion and pixel charging capability, which are the most critical limiting factors for high-quality TFT-LCDs. Since PDAST can simulate the gate data and pixel voltages of a certain pixel on TFT array at any time and at any location on an array, the effect of the new set of capacitance models on the pixel operations can be effectively analyzed, The set of models which is adopted from VLSI interconnections calculate more precise capacitance. The information obtained from this study could be utilized to design the larger area and finer image quality panel.

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손상된 핵산의 구조와 분자동력학적 특성 (Conformational and Molecular Dynamical Properties of Damaged DNA)

  • 박경래;드 로스 산토스 카를로스
    • 약학회지
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    • 제54권1호
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    • pp.67-74
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    • 2010
  • Some of the benzopyrene (BP)-DNA adduct are known to build intercalated motif between flanking base pairs in damaged DNA depending on the structural condition. The size of benzopyrene itself is definitely not comparable with any of the DNA bases and thus the question whether the lesion of some base pair by insertion of benzopyrene can happen with or without a dramatic distortion of the helical structure is a highly interesting theme. In this work we used a molecular dynamics simulation based on the theory of molecular mechanics. The specific consequences about the structural properties of the intercalated structures and benzopyrene motif in minor groove of the double helix are deduced after 5 ns simulation time.