• Journal of Korean Ophthalmic Optics Society
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• v.2 no.1
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• pp.55-60
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• 1997

Numerically compares a calculation about a variable process of visual acuity for a artificial myopia with previously the tested result. The calculation is used to the value of Gullstrand's theoretical eyes and a method of geometrical optics. The theoretical eye simplified a entrance pupil and retina. Optical lens and eye changed a equivalent lens. Refractive power of a equivalent lens is converted to focal length within theoretical eyes, and this was calculated about relation of a blur circle on the retina and visual acuity.

• Proceedings of the Korea Information Processing Society Conference
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• 2022.11a
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• pp.426-428
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• 2022

화재 상황에서의 빠른 현장 파악은 인명피해를 줄이는데 중요한 요소이다. 기존 연구의 화재와 관련된 데이터셋들은 대부분 불과 연기를 라벨링하여 화재의 예방에 초점을 두고 있다. 본 연구에서는 화재 상황에서 사람과 소방관, 연기, 불을 탐지하는 Object detection 모델을 만들어 현장 파악에 더욱 도움을 주고자 하였다. 이를 위해 화재 상황 이미지 약 3000장을 수집하고 라벨링하여 데이터셋을 구성하였으며 이를 이용해 객체 검출 모델인 RetinaNet을 학습하였다. 또한, 화재 상황에서 Object Detection 모델의 성능을 향상시키기 위해 기존 모델인 RetinaNet에 Dehazing(FFA-Net), Smoke augmentation, semi-supervised(ISD) 방법을 적용하였고, semi-supervised 조건에서 mAP 63.7로 가장 높은 성능을 도출하였다.

• Journal of Korean Ophthalmic Optics Society
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• v.10 no.2
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• pp.145-149
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• 2005

In a artificial hypermetropia with the accommodative response, we investigated a diameter of blur circle as a function of test lens refractive power. In a schematic eye model of the hypermetropia, the second focal length along to accommodated power of the crystal lens are calculated as a function of test lens power and, also distance between the retina and exit pupil are calculated as a function of accommodated power. As these results are compared, the size of blur circle on the retina are obtained.

• Journal of Biomedical Engineering Research
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• v.44 no.3
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• pp.211-217
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• 2023

Recently, many studies have introduced artificial intelligence systems in the surgical process to reduce the incidence and mortality of complications in patients. Bleeding is a major cause of operative mortality and complications. However, there have been few studies conducted on detecting bleeding in surgical videos. To advance the development of deep learning models for detecting intraoperative hemorrhage, three models have been trained and compared; such as, YOLOv5, RetinaNet50, and RetinaNet101. We collected 1,016 bleeding images extracted from five surgical videos. The ground truths were labeled based on agreement from two specialists. To train and evaluate models, we divided the datasets into training data, validation data, and test data. For training, 812 images (80%) were selected from the dataset. Another 102 images (10%) were used for evaluation and the remaining 102 images (10%) were used as the evaluation data. The three main metrics used to evaluate performance are precision, recall, and false positive per image (FPPI). Based on the evaluation metrics, RetinaNet101 achieved the best detection results out of the three models (Precision rate of 0.99±0.01, Recall rate of 0.93±0.02, and FPPI of 0.01±0.01). The information on the bleeding detected in surgical videos can be quickly transmitted to the operating room, improving patient outcomes.

• The Journal of the Convergence on Culture Technology
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• v.9 no.5
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• pp.737-745
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• 2023

This paper discusses a study on developing an artificial intelligence model to detect incidents of fires in distribution switchboard using thermal images. The objective of the research is to preprocess collected thermal images into suitable data for object detection models and design a model capable of determining the occurrence of fires within distribution panels. The study utilizes thermal image data from AI-HUB's industrial complex for training. Two CNN-based deep learning object detection algorithms, namely Faster R-CNN and RetinaNet, are employed to construct models. The paper compares and analyzes these two models, ultimately proposing the optimal model for the task.

• Journal of Korean Ophthalmic Optics Society
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• v.5 no.1
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• pp.155-157
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• 2000

A variable process of blur circle is calculated for a artificial hyperopia. The calculation is used to the value of Gullstrand's theoretical eye and a method of geometrical optics. The theoretical eye simplified a entrance pupil and the retina. Ophthalmic lens and eye changed a equivalent lens. Refractive power of a equivalent lens is converted to focal length within theoretical eye, and this is calculated about relation of a blur circle on the retina and ophthalmic lens.

• Journal of Korean Ophthalmic Optics Society
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• v.7 no.1
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• pp.21-23
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• 2002

Compared visual acuity that is measured in a artificial myopia with the numerical calculation. Calculation included image's height as well as blur circle that is formed to retina. The blur circle calculated in geometrical optics model, and height of retinal image calculated by refractive power and visual acuity that is measured in a artificial myopia. Define this result as "blur ratio" about blur circle and height of retinal image, and investigated blur ratio relationship about visual acuity in a artificial myopia.

• Development and Reproduction
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• v.4 no.1
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• pp.19-28
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• 2000

Diploid and triploid hybrid between female mud loach Misgurnus mizolepis and male cyprinid loach, M. andguillicaudatus were produced, using artificial propagation. The influence of hybridization and triploidization on characteristics of the some tissues of retina optic tectum and trunk kidney in loach was determined histologically. Diploid hybrid have almost size similarities in nucleus and the cell size of some tissues to both parents. In the triploid hybrid the nucleus and／or the cell size in erythrocyte, horizontal cell in inner nuclear layer of retina ganglion cell in ganglion cell layer of retina, neuronal cell in granular layer of optic tectum, and secondary proximal tubule cell of trunk kidney, are much larger than those of the corresponding cells in the diploid hybrid individuals. However, triploid hybrid showed fewer number of cells in outer nuclear layer in retina and nuclei in secondary proximal tubule of trunk kidney than in diploid hybrid. Results of this study suggest that some characteristics in the triploid hybrid exhibiting larger cell and nucleus size with fewer number of cell than diploid hybrid can be useful criteria for the distinction between diploid hybrid and triploid hybrid, and the ploidy level in loach.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.4
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• pp.466-475
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• 2005

Docosahexaenoic acid (22:6n-3, DHA) is highly enriched in membrane of brain and retina, and plays an important role in maintaining an optimal function of the central nervous system. We investigated the effect of n-3 fatty acid deficiency on rat brain, retina and liver fatty acyl composition at two different ages (3 wks and 15 wks) under DHA deficient condition. Rat pups born to dams fed a diet with $3.1\%$ of total fatty acids as $\alpha-linolenic$ acid (LNA) were fed using an artificial rearing system either an n-3 deficient (n-3 Def) or n-3 adequate (n-3 Adq) diet. Both diets contained $17.1\%$ linoleic acid (LA) but the n-3 Adq diet also contained $3.1\%$ LNA. Rats consuming the n-3 Def diet showed a lower brain $(50\%\;in\;13\;wks\;and\;70\%\;in\;15\;wks,\;p<0.05)$ and retinal $(50\%\;in\;13\;wks\;and\;63\%\;in\;15\;wks,\;p<0.05)$ DHA than those on the n-3 Adq diet, which was largely compensated for by an increase in docosapentaenoic acid (22:5n-6, DPAn-6). In the liver of the n-3 Def group, the percentage of DHA decreased by $97\%$ at 3 wks of age with an apparent increase in DPAn-6 relative to the n-3 Adq group (p<0.05), while there was a $65\%$ lower liver DHA in n-3 Def group at 15 wks of age than the n-3 Adq group (p<0.05). Liver arachidonic acid (20:4n-6, AA) was increased at 3 wks of age but decreased at 15 wks of age in the n-3 Def group compared with n-3 Adq group (p<0.05). In conclusion, the replacement of DHA by DPAn-6 in brain and retina fatty acid composition may be related to the suboptimal function in spatial learning, memory and visual acuity. This artificial rearing method presents a first generation model for n-3 deficiency that is similar to the case of human nutrition that commonly employed two generation model.

• Proceedings of the KIEE Conference
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• 2001.11a
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• pp.43-44
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• 2001

인공망막에서의 신호와 파워의 전달은 상당히 중요하고 어려운 일이다 본 연구에서는 레이저 어레이를 사용하여 망막 내에 삽입된 인공망막에 신호와 파워를 전달하는 방법에 대해 연구하고 그러한 시스템을 설계하여 시뮬레이션하였다. 시뮬레이션 결과 $50{\mu}m{\times}50{\mu}m$ 인 포토다이오드에 각 레이저가 충분히 포커싱됨을 확인할 수 있었고 2차원 어레이로서 일대일 대응이 가능함을 보였다.