• 제목/요약/키워드: Residual correction

검색결과 199건 처리시간 0.023초

블러기반 움직임 벡터와 오차 영상 보상을 이용한 물체지향 부호화기 (Object-oriented coder using block-based motion vectors and residual image compensation)

  • 조대성;박래홍
    • 전자공학회논문지B
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    • 제33B권3호
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    • pp.96-108
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    • 1996
  • In this paper, we propose an object-oriented coding method in low bit-rate channels using block-based motion vectors and residual image compensation. First, we use a 2-stage algorithm for estimating motion parameters. In the first stage, coarse motion parameters are estimated by fitting block-based motion vectors and in the second stage, the estimated motion parametes are refined by the gradient method using an image reconstructed by motion vectors detected in the first stage. Local error of a 6-parameter model is compensted by blockwise motion parameter correction using residual image. Finally, model failure (MF) region is reconstructed by a fractal mapping method. Computer simulation resutls show that the proposed method gives better performance than the conventional ones in terms of th epeak signal to noise ratio (PSNR) and compression ratio (CR).

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풍화잔적토의 불포화전단강도 예측 및 특성연구 (Characteristics and Prediction of Shear Strength for Unsaturated Residual Soil)

  • 이인모;성상규;양일순
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2000년도 가을 학술발표회 논문집
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    • pp.377-384
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    • 2000
  • The characteristics and prediction model of the shear strength for unsaturated residual soils was studied. In order to investigate the influence of the initial water content on the shear strength, unsaturated triaxial tests were carried out varying the initial water content, and the applicability of existing prediction models for the unsaturated shear strength was testified. It was shown that the soil - water characteristic curve and the shear strength of the unsaturated soil varied with the change of the initial water content. A sample compacted in the lower initial water content needs a higher suction to get the same degree of saturation while the shear strength of a sample with the lower initial water content displays a lower value. In order to apply the existing prediction models of the unsaturated shear strength to granite residual soils, a correction coefficient, α, on the internal friction angle, ø'was added.

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성인 20 세 이상 활로 4징증의 수술성적 (Surgical Correction of Tetralogy of Fallot in Adults over 20 Years of Age)

  • 정윤섭
    • Journal of Chest Surgery
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    • 제23권2호
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    • pp.253-259
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    • 1990
  • Between January, 1970 and August, 1989, a total of 81 patients whose age were more than 20 years of life, received total correction for tetralogy of Fallot. This report analyzed 70 patients among them and excluded the remaining 11 patients whose clinical data could not be found. Their mean age was 25.750.39 years[range 20 \ulcorner50]. The clinical manifestations were cyanosis and clubbing [64 pts], frequent URI[40 pts], anoxic spell [19 pts], infective endo-carditis[4 pts], brain abscess[3 pts], pulmonary tuberculosis[3 pts] and CHF, chest tightness, nephrotic syndrome, left hemiplegia, and tamponade. The types of right ventricular outflow tract obstruction were combined[46 pts], pure infundibular [21 pts] and pure valvular[3 pts]. Associated cardiovascular anomalies were PFO [27 pts], ASDi8 pts], LSVC[8 pts], aortic regurgitation [5 pts], right aortic arch, coronary artery anomalies, PDA and dextrocardia. Hospital mortality was 5.7%. The causes of death ware low cardiac output [2 pts], aggravation of CRF[1 pts] and brain damage[1 pts]. There was one late death because of residual intracardiac shunt and congestive heart failure. During the follow-up period, 16 patients were lost and the remaining 49 patients were asymptomatic and leading normal lives. Residual intracardiac shunt was detected in 5 patients with radionuclide single pass study but all of them had Qp / Qs ratio less than 1.5.

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Practical stepwise approach to rhythm disturbances in congenital heart diseases

  • Huh, June
    • Clinical and Experimental Pediatrics
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    • 제53권6호
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    • pp.680-687
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    • 2010
  • Patients with congenital heart diseases (CHD) are confronted with early- and late-onset complications, such as conduction disorders, arrhythmias, myocardial dysfunction, altered coronary flow, and ischemia, throughout their lifetime despite successful hemodynamic and/or anatomical correction. Rhythm disturbance is a well-known and increasingly frequent cause of morbidity and mortality in patients with CHD. Predisposing factors to rhythm disturbances include underlying cardiac defects, hemodynamic changes as part of the natural history, surgical repair and related scarring, and residual hemodynamic abnormalities. Acquired factors such as aging, hypertension, diabetes, obesity, and others may also contribute to arrhythmogenesis in CHD. The first step in evaluating arrhythmias in CHD is to understand the complex anatomy and to find predisposing factors and hemodynamic abnormalities. A practical stepwise approach can lead to diagnosis and prompt appropriate interventions. Electrophysiological assessment and management should be done with integrated care of the underlying heart defects and hemodynamic abnormalities. Catheter ablation and arrhythmia surgery have been increasingly applied, showing increasing success rates with technological advancement despite complicated arrhythmia circuits in complex anatomy and the difficulty of access. Correction of residual hemodynamic abnormalities may be critical in the treatment of arrhythmia in patients with CHD.

다중경로 페이딩 채널에서 주파수 옵셋 보상 알고리즘을 적용한 디지털 M/W 전송 시스템의 성능 분석 (Performance Analysis of Digital M/W Transmission System adopting Frequency Offset Compensation Algorithm in Multipath Fading Channel)

  • 박기식
    • 한국컴퓨터정보학회논문지
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    • 제18권10호
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    • pp.63-70
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    • 2013
  • 본 논문에서는 다중 경로 페이딩 채널을 고려한 환경에서 디지털 M/W전송 시스템의 동기에 관한 모의 시뮬레이터를 구성하여 주파수 동기를 수행하였고, 송신단과 수신단의 주파수 허용 편차(오실레이터 간 오차 범위)로 발생되는 주파수 옵셋에 보상 알고리즘을 적용하여 신호 성좌도(constellation)의 성능 개선 정도를 평가하였다. 성능 분석 결과, 송 수신단의 주파수 허용 편차가 큰 상태에서는 주파수 옵셋을 보상해도 주파수 허용 편차가 이미 크기 때문에 잔류 주파수의 영향을 상대적으로 많이 받게 됨을 알 수 있었다. 결과적으로 송수신단의 주파수 허용 편차에 따라 잔류 주파수 옵셋이 시스템 성능에 큰 영향을 미치게 됨을 알 수 있었다. 본 결과물은 향후 방송중계용 시스템의 대역 이전 시 필요한 주파수 동기 기준으로 활용 가능할 것이다.

고변형률 영역의 유효응력-변형률 곡선을 고려한 고탄소강 다단 신선 와이어 축방향 잔류응력 평가 (Evaluation of Axial Residual Stress in Multi-Pass Drawn High Carbon Steel Wire Considering Effective Stress-Strain Curve at High Strain)

  • 이상곤;김대운;김병민;정진영;반덕영;이선봉
    • 한국정밀공학회지
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    • 제27권8호
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    • pp.70-75
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    • 2010
  • The aim of this study is to evaluate the axial residual stress in multi-pass drawn high carbon steel wire by using FE analysis and XRD. When FE analysis is applied to evaluate the residual stress in drawn wire of multi-pass drawing process, obtaining the reliable effective stress-strain curve at high strain is very important. In this study, a model, which can express the reliable effective stress-strain curve at high strain, is introduced based on the Bridgman correction and tensile test for multi-pass drawn high carbon steel wires. By using the introduced model, FE analysis was carried out to evaluate the axial residual stress in the drawn wires. Finally, the effectiveness of the FE analysis with the introduced stress-strain relation was verified by the measurement of residual stress in the drawn wires through XRD. As a result, the evaluated residual stress of FE analysis shows good agreement with the measured residual stress.

GPS와 Echo Sounder를 이용한 하상 모니터링 (Estuary Riverbed Monitoring using GPS and Echo Sounder)

  • 홍정수;이용희;이기부;이동락
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2006년도 춘계학술발표회 논문집
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    • pp.83-88
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    • 2006
  • We intend to increase in efficiency of the topographic monitoring of seabed or riverbed by combined with DGPS, RTK GPS and echo sounder. For this study, we defined the error correction of the echo sounder with the experiment of water tank, which is considered the characteristic of estuary riverbed and then we developed the s/w for 3-dimensional monitoring of estuary riverbed and applied the s/w to field test and improved the various problems. On analyzing topography of estuary riverbed by combined GPS with echo sounder, the draught error which is yielded to change of length from the water surface by the movement of survey vessel to the end of the transducer was eliminated by geometrical rearrangement and we defined the correction formula, z = BM+ SAH- $DBR_{(i)}$ - DRT - ED. The sounding error about the echo sounder and characteristic of estuary riverbed was found by understanding the relation of average diameter and residual error and we defined correction formula, Y= -0.00474*In(X) -0.0045 by the regression analysis. and then we verified applicability of correction formula.

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안와골파열골절 정복술 후 지속되는 안구함몰 환자에서 정상측 안구의 안구 감압술의 치험례 (Correction of Persistent Enophthalmos after Surgical Repair of Blow Out Fracture Using Orbital Decompression Technique of Contralateral Eye)

  • 이준호;박원용;남현재;김용하
    • 대한두개안면성형외과학회지
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    • 제9권2호
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    • pp.101-104
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    • 2008
  • Purpose: Diplopia and cosmetically unacceptable enophthalmos are the major complications of blow out fracture. Prolapse of orbital tissue into the sinuses, enlarged orbital volume, atrophy of orbital fat and loss of support of orbital walls play a role in the pathogenesis of enophthalmos. To correct post-traumatic enophthalmos, freeing of incarcerated orbital contents combined with reduction of bony orbital volume and reconstruction of suspensory support of globe is necessary. But remained enophthalmos after surgical treatment is difficult to correct completely. In this case, the authors performed implant insertion for affected orbit and endoscopic orbital decompression for unaffected orbit for correction of late enophthalmos. Method: We reviewed a girl patient with right inferomedial orbital wall blow out fracture, right zygoma fracture treated at our hospital for correction of enophthalmos. An 18-year-old female had sustained posttraumatic enopthalmos. Two surgical management was performed for correction blow out fracture at the other hospital. But residual diplopia, enophthalmos, cheek drooping were found. And then she transferred to our hospital. She had severe enophthalmos(5 mm) also had diplopia and extraocular muscle limitation. We performed operation for correction of enophthalmos. After operation, she showed minimal improvement of diplopia and enophthalmos(3 mm). The authors make plan for operation for correction enophthalmos due to cosmetical improvement. Implant insertion was performed for affected orbit. For unaffected orbit, nasoendoscopic medial orbital wall decompression was proceeded. Result: Correction of enophthalmos was found after operation and was maintained for nine years follow-up. Patient expressed satisfaction for the result. Conclusion: To correct persistant enophthalmos, we could have satisfactory result with orbital wall reconstruction on affected eye and decompression on unaffected eye.

Network RTK 품질 분석 방법론별 성능 지표와 사용자 항법 정확도의 상관성 (Correlation between the Position Accuracy of the Network RTK Rover and Quality Indicator of Various Performance Analysis Method)

  • 임철순;박병운;허문범
    • 한국항행학회논문지
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    • 제22권5호
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    • pp.375-383
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    • 2018
  • 정지한 객체의 측위에 사용되던 Network RTK (real time kinematics) 기술을 이동형 항체의 항법에 적용하기 위해서는 보정정보와 함께 사용자의 성능을 대표할 수 있는 지표가 함께 제공되어야 한다. 이를 위하여 본 논문에서는 I95 (ionospheric index 95) / G95 (geodetic index 95), SBI (semivariance based index), RIU (residual interpolation uncertainty) 등의 지표 도출 알고리즘을 분석하고 이를 국토지리정보원의 기준국 원시 데이터와 VRS (virtual reference station) 사용자에 적용함으로써 정밀 항법 성능 지표로의 활용 가능성을 타진하였다. 24시간 데이터를 처리한 결과 보정정보의 비선형성을 나타낼 수 있는 RIU 지표와 Network RTK 사용자의 위치 정확도와의 상관성이 0.52로 타 지표에 비해 훨씬 높은 것으로 나타났으므로 향후 이동 항체의 항법 성능 지표로 사용이 가능할 것으로 예상된다.

2-체널 링-코어 프럭스-게이트 콤파스의 성능평가 시스템 개발 (Performance Evaluation System for Tow-Channel Ring-Core Flux-Gate Compass)

  • 임정빈;정중식;박성현;김봉석
    • 한국항해항만학회지
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    • 제26권5호
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    • pp.529-535
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    • 2002
  • 2-체널 링-코어 프럭스-게이트 콤파스(Two-Channel Ring-Core Flux-Gate Compass; TCRC FG-Compass)의 성능평가 시스템 설계와 구현방법 및, 다항회귀 모형 기반의 평가 절차와 방법을 기술했다. 성능평가 시스템은 스템모터 구동 유닛과, 방위정보 전송 유닛, 다항회귀식에 의한 평가 프로그램 등으로 구성하였다. 성능평가 실험결과, TCRC FG-Compass는 잔차가 $2^{\circ}$인 반면, 기존의 FG-Compass는 잔차가 $4^{\circ}$임을 나타냈다. 따라서 성능이 향상된 새로운 FG-Compass 설계가 가능함을 확인하였다. 또한, 자동으로 잔차를 추정하고 보정할 수 있는 설계론에 관해서도 논의하였다.