• 한국정밀공학회지
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• 제22권9호
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• pp.115-122
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• 2005

Errors resulting from magnification variations of a optical system are largely generated in three-dimensional shape measurements based on depth-from-focus. In the case of measuring the surface morphology of tiny objects based on DFF, images are acquired with a very small interval so that magnification changes can be minimized. However, the magnification variations are actually existed in the acquired images and so focus measures are wrongly or ambiguously extracted. In this paper, a methodology with linear magnification calibrations, based on DFF, is proposed to make more accurate measurement in surface morphology with high depth discontinuity, compared with previous ones. Several experiments show that the proposed method outperforms existing ones without magnification calibrations.

• 대한디지털의료영상학회논문지
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• 제15권2호
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• pp.39-44
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• 2013

Purpose : The purpose of this study is the magnification rates depending on the area of patient dose (DAP) and glass dosimeter see the change of the dose according to the dose characteristics of low-magnification aims to raise standards. Materials and Method : Direct DR equipment Sonialvision DAR-8000f, Shimadzu was used, the patient entrance dose measurements to the surface of the Rando Phantom of the neck and the abdomen was placed on the Xi unfors. glass dosimeter for measuring organ doses at the same time the Rando Phantom of the major organs in place by inserting a 9 ", 12", 15 ", 17" and 30 seconds for each magnification were measured according in fluoroscopy. DAP meter area of the patient dose was measured. Result : Esophagography at 17" 143% than 9"magnification the average area dose was increased. Organ dose of Esophagography at 17" was decreased 25.32% than 9" magnification. UGI at 17" was increased 129.73% DAP than 9" magnification. Organ dose of UGI at 17" was decreased 23.32% than 9" magnification. Where the major organs of magnification at 17" were decreased(lung -25.96%, stomach -33.09%, spleen -27.81%, liver -4.92%) than 9" magnification. Conclusion : Expected to get better quality image While using the proper magnification, and have recognition that difference Organ doses and DAP meter in fluoroscopy.

• 치과방사선
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• 제16권1호
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• pp.25-30
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• 1986

The author studied the magnification ratio of teeth length in orthopantomogram through intraoral film taken by standardized paral1eing technique. In this study, intraoral radiograph and orthopantomogram were taken in 2 cases of dry skull and 36 adults (504 teeth). 1. The obtained results were as follows: In case of dry skull, the magnification ratio of standard films was 4.6% to 5.9% and that of Orthopantomograph 5 was 15.1% to 33.1%. The magnification ratio of to the standard film was 9.2% to 26.5% 2. In case of adults, the magnification ratio of Orthopantomograph 5 to the standard films was 9.5% to 24.6%. 3. There were no significant difference in magnification between left and right. 4. Anterior teeth had lesser magnification than posterior teeth. 5. It was considered that teeth length showed in Orthopontomograph 5 was magnified 15.4% to 31.3% than actual teeth length.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.1500-1503
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• 2004

Errors resulting from magnification variations of optical system are largely generated in three-dimensional shape measurements. In the case of measuring the surface morphology of tiny objects based on DFF, images are acquired with a very small interval and then magnification changes are minimized. However, the magnification variations are actually existed in optical system and so focus measures in DFF are wrongly or ambiguously extracted. in this paper, a methodology based on DFF with the magnification changes is proposed to make more accurate measurement in surface morphology with high depth discontinuity, compared with previous ones. Several experiments show that the proposed method outperforms existing ones without magnification changes.

• Journal of Korean Dental Science
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• 제10권2호
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• pp.53-59
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• 2017

Purpose: The objective of the present article is to determine whether there are differences in vertical enlargement ratio among various sites within both jaws in a panoramic radiograph. Materials and Methods: Two hundred and seventy-threeimplant sites in panoramic radiographs were evaluated by two observers. Magnification ratios at various sites in both jaws were calculated and compared with each other. Result: The average vertical enlargement ratio in the panoramic radiograph was 1.264 and this value was larger than original ratio 1.250. Although vertical magnification ratio of maxillary molar area was higher than that of mandibular molar area, every group showed similar magnification ratio in clinical respect. Conclusion: Vertical magnification ratio of the maxillary molar area is statistically higher than that of the mandibular molar area in the panoramic radiograph, but it is clinically negligible.

• 한국정보통신학회논문지
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• 제10권12호
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• pp.2343-2348
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• 2006

영상처리에서 영상확대기법은 기본적인 처리기법으로 일반적으로 사용되는 기법은 보간법(최근접이웃, 양선형, 3차회선 보간법)이다. 그러나 이러한 보간법은 영상확대시 블록화 현상이나 몽롱화현상과 같은 영상의 손실이 발생하거나 계산량이 많아 처리시간이 길게 나타났다. 따라서 본 논문에서는 입력영상의 부대역정보인 에지정보를 이용하여 기존의 확대기법을 개선하고자 한다. 에지정보를 추출하기 위하여 이웃한 화소들을 이용하지 않고 전체영상을 이용하여 블록화현상이 발생되지 않았다. 그리고 에지가 결여되어 나타나는 몽롱화현상을 제거하기 위하여 검출된 에지정보를 강조시켰다. 실험 결과, 제안된 기법은 기존의 확대기법보다 처리시간을 줄일 수 있었으며, PSNR과 상관계수에서도 성능이 뛰어나 블록화나 몽롱화현상과 같은 문제점을 해결하였다.

• 한국기계가공학회지
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• 제7권2호
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• pp.60-65
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• 2008

The high-technology industries including a semi-conductor and an information communication need an ultra-precision technology from the technological points of view. Nano technology based on an ultra-precision technology is being studied to overcome the delicate technology that may occur in the semi-conductor fields. Then, the transferring equipment with high resolution and long displacement becomes an important technology. The goal of this study is to analyze the displacement magnification mechanism driven by piezoelectric actuator which has high resolution and fast response characteristics using flexure hinge with the merits of soft displacement, negligible back-lash and stick-slip, and no-lubrication. The analyses to reduce the magnification losses occurred during the magnification process are performed using ANSYS software based on FEM. The five design variables such as arm thickness, thickness of hinge, radius of hinge, length of input side at the 1st lever and magnification ratio of 1st lever are optimized to induce the maximum magnification ratio using Taguchi method.

• 치과방사선
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• 제21권2호
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• pp.287-296
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• 1991

The purpose of this experiments is to compare the vertical and horizontal magnification, and the distortion of the radiographic image according to the types of panoramic machines. Total 70 radiographs, 10 radiographs out of 7 panoramic machines respectively, were taken from the dry skull with metal balls in the periapical areas of the central incisor, the canine, the second premolar, and the second molar in the maxilla and the mandible. And the author evaluated the vertical and horizontal magnification degrees, and the distortion degrees of radiographic images obtained from each panoramic machine. The results were as follows: There were no significant differences in the vertical and horizontal magnification degrees on the various portions of the jaws (p> 0.05). But there were higher magnification degrees in the Panoura 10C, Panograph Ⅱ, and Veraview than those in other panoramic machines. The lowest average magnification degree was 20.27% vertically, 20.94% horizontally using the Panoradix. The highest average magnification degree was 27.64% vertically, 28.48% horizontally using the Panograph Ⅱ. The lowest distortion was shown using the Panoura 10C in the maxilla, but there was not statistically significant difference between the panoramic machines in the mandible (p>0.05). There were no differences in the vertical and horizontal magnification degrees according to the types of the rotation centers.

• 한국정보통신학회논문지
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• 제25권11호
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• pp.1477-1485
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• 2021

최근 이미지 초해상도는 정수배율만 가능한 모델에만 집중적으로 연구되고 있다. 하지만 관심 객체 인식, 디스플레이 화질 개선 등 실제 초해상도 기술의 대표 적용 분야에서는 소수 배율을 포함하는 임의배율 확대 필요성이 대두되고 있다. 본 논문에서는 기존 정수배율 모델의 가중치를 활용하여 임의배율을 실행할 수 있는 모델을 제안한다. 이 모델은 정수배율에 의해 우수한 성능을 가진 초해상도 결과를 DCT 스펙트럼 도메인으로 변환하여 임의배율을 위한 공간을 확장한다. DCT 스펙트럼 도메인에 의한 확장으로 인해 발생하는 이미지의 고주파 정보 손실 문제를 줄이기 위해 고주파 스펙트럼 정보를 적절히 복원할 수 있는 모델인 고주파 집중 네트워크를 제안한다. 제안된 네트워크는 고주파 정보를 제대로 생성하기 위해서 RGB 채널간의 상관관계를 학습하는 레이어인 channel attention을 활용하고, 잔차 학습 구조를 통해 모델을 깊게 만들어 성능을 향상시켰다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1273-1276
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• 2005

A displacement magnification mechanism is usually employed in a nano-positioning stage to achieve a large stage motion. A lever mechanism is the most widely used displacement magnifying mechanism. For more large stage motion, double or multiple lever mechanisms can be used. In this case, a more accurate analysis model is needed. This study proposes a more reasonable analysis model for a multiple lever mechanism based on the single lever mechanism model. This paper describes that the high equivalent stiffness of the lever is the most important factor reducing the magnification ratio of the lever mechanism through increasing the deflection of the link and including the axial displacement of the pivot.