• 한국정보통신학회논문지
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• 제18권12호
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• pp.3035-3041
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• 2014

3D 애니메이션 제작 과정에서 가상 카메라의 이동을 보다 자연스러운 영상으로 표현하기 위해서 스테디캠 기법을 많이 사용하고 있다. 가상카메라에서 스테디캠 효과를 표현하기 위한 기존의 방식은 키프레임을 이용하는 것으로 카메라의 모든 움직임을 수작업으로 처리한다. 그러나 영상에서 카메라 워킹을 수작업으로 처리하는 것은 제작 시간이 많이 소요되는 번거로운 작업이며 카메라의 움직임이라는 물리적 현상을 인위적으로 표현함으로써 부자연스러운 결과를 얻는다. 본 연구는 3D 애니메이션에서 가상카메라의 이동에 따라 카메라에 가해지는 물리적 현상을 모델링하여 자동으로 스테디캠 효과를 낼 수 있는 방식을 제안한다. 제안하는 물리적 모델링은 파이선 스크립트 언어로 구현되어 마야의 제작 플랫폼에서 바로 적용 가능하다. 제안하는 방법은 기존의 수기적인 제작환경을 개선하고 영상의 자연스러운 시각적 효과를 극대화 할 수 있다.

• Clinical and Experimental Reproductive Medicine
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• 제46권2호
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• pp.87-94
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• 2019

Objective: The primary objective of this study was to compare clinical pregnancy rates in intrauterine insemination (IUI) treatment cycles with transabdominal ultrasound guidance during intrauterine catheter insemination (US-IUI) versus the "blind method" IUI without ultrasound guidance (BM-IUI). The secondary objective was to compare whether US-IUI had better patient tolerability and whether US-IUI made the insemination procedure easier for the clinician to perform compared to BM-IUI. Methods: This was a randomized controlled trial done at the Reproductive Medicine Unit of General Hospital Kuala Lumpur, Malaysia. We included women aged between 25 and 40 years who underwent an IUI treatment cycle with follicle-stimulating hormone injections for controlled ovarian stimulation. Results: A total of 130 patients were recruited for our study. The US-IUI group had 70 patients and the BM-IUI group had 60 patients. The clinical pregnancy rate was 10% in both groups (p> 0.995) and there were no significant difference between the groups for patient tolerability assessed by scores on a pain visual analog scale (p= 0.175) or level of difficulty for the clinician (p> 0.995). The multivariate analysis further showed no significant increase in the clinical pregnancy rate (adjusted odds ratio, 1.07; 95% confidence interval, 0.85-1.34; p= 0.558) in the US-IUI group compared to the BM-IUI group even after adjusting for potential covariates. Conclusion: The conventional blind method for intrauterine catheter insemination is recommended for patients undergoing IUI treatment. The use of ultrasound during the insemination procedure increased the need for trained personnel to perform ultrasonography and increased the cost, but added no extra benefits for patients or clinicians.

• 한국지리정보학회지
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• 제6권3호
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• pp.107-116
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• 2003

이 연구는 기존의 분광특성에 의한 영상분류방법들이 고해상도 위성영상에 어느 정도 적절한지 알아보는데 목적이 있다. 이를 위하여 매개변수법과 비매개변수법을 혼합한 감독분류, 퍼지이론을 적용한 감독분류 그리고 무감독분류방법을 각각 적용하여 토지피복분류를 실시하고 각 방법들의 적용결과를 서로 비교하였다. 또한 육안판독과 분광특성을 이용한 영상분류 결과를 서로 비교하여 각 방법 간 토지피복분류의 결과를 비교 분석하였다. 실증연구 결과, 고해상도 위성영상은 반사값의 복잡성, 그림자의 영향 등으로 인하여 노이즈 현상이 심하게 발생하였다. 이러한 고해상도 위성영상은 무감독분류보다는 감독분류가 더 적절한 분석방법이며, 특히 퍼지이론을 적용한 감독분류방법이 가장 우수한 것으로 나타났다. 그러나 토지피복분류결과의 전체 정확도가 76% 정도에 불과해 토지피복분류결과의 신뢰성이 낮았다. 또한 육안판독과 영상분류 결과를 서로 비교한 바 뚜렷한 경계와 넓은 면적을 갖는 농경지 등의 항목은 일치도가 높은 반면 산발적으로 분포해 있는 초지 등의 항목은 일치도가 낮게 나타났다. 영상분류와 육안판독 간의 일치도는 79%로 나타났다.

• 한국음향학회지
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• 제29권8호
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• pp.504-508
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• 2010

기존의 초음파 의료용 탄성영상에서 변형률 영상을 모니터에 표시할 때 인간 시각 특성을 반영하여 단단한 부위는 어둡게 표시하고 무를수록 밝게 나타낸다. 따라서 종양이나 암이 존재하는 단단한 부위는 어둡게 나타나서 병변 내부의 콘트라스트는 저하되어 나타난다. 병변 영역은 단단하여 변형률 영상에서 어둡게 나타나므로 병변 내부를 좀 더 자세히 진단하는 방법으로, 누른 후의 신호를 누른 변형률만큼 다시 신장시켜서 얻는 전역 균일 신장 방법을 적용하여 영상의 명암을 반전시킴으로써 병변 부분의 콘트라스트를 올리는 방법을 제안하였다. 의료용 초음파 영상 진단기를 이용하여 탄성 모사 팬텀에서 초음파 데이터를 얻어서 제안한 알고리즘을 검증하여 유용성을 확인하였다. 전역 균일 신장 없이 회색조 컬러 맵을 반전해서 얻은 변형률 영상법에 비해 콘트라스트 대 잡음비가 최대 1.8배 정도 향상되었다.

• 한국산학기술학회논문지
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• 제11권12호
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• pp.5127-5133
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• 2010

본 논문에서는 히스토그램 명세화에 기반을 둔 효과적인 영상 대비 개선 알고리즘을 제안한다. 히스토그램 평활화나 이로부터 파생된 방법들은 영상 대비 개선에 효과적인 도구로 사용되어 왔으나, 과도한 대비 개선이라는 부작용을 수반하는 결과를 자주 낳게 된다. 반면 기존의 히스토그램 명세화는 의도한 히스토그램을 얻기에 부적절하다는 단점을 가지고 있다. 본 논문에서는 의도한 히스토그램을 얻기 위해서 고주파필터를 활용한 방법을 제안한다. 제안한 방법은 기존의 영상 대비 방법에 대해서 향상된 화질을 제공할 뿐만 아니라, 영상의 통계적 속성에 적응적으로대응하는 속성을 보여주고 있다.

• The Journal of Korean Physical Therapy
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• 제17권4호
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• pp.559-567
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• 2005

The purpose of this research is to study how the stretching exercise along with heat and electric therapy can effect on Angle of Lumbar Flexion and Reduction of Pain against the Hamstring Construction Symptom that can be found in the Chronic Low Back Patients. The target of research was 28 person selected out of the patients diagnosed as Lumbar Sprain and Lumbar Syndrome, who have positive from the active test of Hamstring construction and passive test. Their age range is 20 to 60 years old, 14 male and 14 female. As a research method, simple heat and electric therapy was applied to counter part while Hamstring Stretching Exercise including simple heat and electric therapy was applied to the experimental part. After 6 weeks treatment for each part, the results of effect on Angle of Lumbar Flexion and Pain Reduction was compared and analysed on the basis of the gravity angle meter and Visual Analogue Scale (VAS). The outcome of research is as follows: 1. Angle of Lumbar Flextion increased effectively not in the conventional counter group but the experimental group to which Hamstring Stretching was applied simultaneously. 2. remarkable effect was shown in the experimental part applied Hamstring Stretching. Consequently from the results of this study, we could find out the fact that the therapy combined preserve treatment and hamstring stretching not only produced increasing Lumbar Flexion Angle but also was more effective on reducing pain of the patients according to it than the conventional or preserve therapy.

• Structural Monitoring and Maintenance
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• 제1권4호
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• pp.357-369
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• 2014

In the existing bridge management systems, assessment of the structural behavior is based on the results of visual inspections in which corresponding condition states are assigned to individual elements. In this process, limited attention is given to the correlation between bridge elements from structural perspective. Also, the uncertainty of parameters which affect the structural capacity is ignored. A system reliability-based assessment model is potentially an appropriate replacement for the existing procedures. The aim of this research is to evaluate the system reliability of existing conventional Steel-Reinforced bridge decks over time. The developed method utilizes the reliability theory and evaluates the structural safety for such bridges based on their failure mechanisms. System reliability analysis has been applied to simply-supported concrete bridge superstructures designed according to the Canadian Highway Bridge Design Code (CHBDC-S6) and the deterioration pattern is achieved based on the reliability estimates. Finally, the bridge condition index of an old existing bridge in Montreal has been estimated using the developed deterioration pattern. The results obtained from the developed reliability-based deterioration model and from the evaluation done by bridge engineers have been found to be in accordance.

• Journal of information and communication convergence engineering
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• 제9권2호
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• pp.201-206
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• 2011

FRUC (Frame Rate Up-Conversion) technique needs an effective frame interpolation algorithm using motion information between adjacent neighboring frames. In order to have good visual qualities in the interpolated frames, it is necessary to develop an effective detection and interpolation algorithms for occluded regions. For this aim, this paper proposes an effective occluded region detection algorithm through the adaptive forward and backward motion searches and also by introducing the minimum value of normalized cross-correlation coefficient (NCCC). That is, the proposed scheme looks for the location with the minimum sum of absolute differences (SAD) and this value is compared to that of the location with the maximum value of NCCC based on the statistics of those relations. And, these results are compared with the size of motion vector and then the proposed algorithm decides whether the given block is the occluded region or not. Furthermore, once the occluded regions are classified, then this paper proposes an adaptive interpolation algorithm for occluded regions, which still exist in the merged frame, by using the neighboring pixel information and the available data in the occluded block. Computer simulations show that the proposed algorithm can effectively classify the occluded region, compared to the conventional SAD-based method and the performance of the proposed interpolation algorithm has better PSNR than the conventional algorithms.

• 대한치과마취과학회지
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• 제6권2호
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• pp.98-102
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• 2006

The purpose of this study was to evaluate the difference on pain intensity and discomfort between pressure-controlled injection system and conventional syringe injection technique from the patients undergoing oral and maxillofacial surgery. In a prospective, randomized, case-controlled study, 60 patients were divided into two groups (n=30 in each). In experimental group, pressure-controlled injection system was applied. In control group, conventional syringe injection system was applied. Pain rating score (PRS) and visual analogue scale (VAS) were assessed. The average of VAS in experimental group ($16.67{\pm}15.07$) was smaller than that of control group ($25.63{\pm}22.21$), though there were no significant differences (P=0.072). In PRS, fifteen patients (50.0%) of experimental group answered that they experienced mild pain. However sixteen patients (53.3%) of control group answered that they experienced intermediate pain. From the results, pressure-controlled injection system may be an effective method to reduce pain during the dental local anesthetic procedure.

• 제어로봇시스템학회논문지
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• 제9권7호
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• pp.507-514
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• 2003

Inspection and shape measurement of three-dimensional objects are widely needed in industries for quality monitoring and control. Recently the shape measurement using interferometric principle is found to be a successful methodology among other visual or optical technologies. Especially, the measuring method using wavelength scanning interferometer(WSI) has a great advantage in comparison with other conventional jnterferometric methods in that the absolute distance from the reference surface can be directly obtained from the amount of jnterferometric phase change. However, the measurement methods using WSI proposed by other researchers have low measurement resolution so far because they can't measure fractional phase change. To avoid this shortcoming we propose a new algorithm in this paper, which can obtain a small amount of even fractional phase change by sinusoidal function fitting. To evaluate the effectiveness of the proposed sinusoidal function fitting algorithm, a series of measuring experiments are conducted for discontinuously shaped specimens which have various height. The proposed algorithm shows much more enhanced measurement resolution than other existing conventional algorithms such as zero crossing algorithm and Fourier transform algorithm.