• Journal of Electrical Engineering and Technology
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• v.7 no.2
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• pp.221-224
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• 2012

We propose a Readout Integrated Circuit (ROIC), which applies a fixed current bias sensing method to the input stage in order to simplify the circuit structure and the infrared sensor characteristic control. For the sample-and-hold stage to display and control a signal detected by the infrared sensor using a two-dimensional (2D) focal plane array, a differential delta sampling (DDS) circuit is proposed, which effectively removes the FPN. In addition, the output characteristic is improved to have wider bandwidth and higher gain by applying a two-stage variable gain amplifier (VGA). The output characteristic of the proposed device was 23.91 mV/$^{\circ}C$, and the linearity error rate was less than 0.22%. After checking the performance of the ROIC using HSPICE simulation, the chip was manufactured and measured using the SMIC 0.35 um standard CMOS process to confirm that the simulation results from the actual design are in good agreement with the measurement results.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1061-1063
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• 2003

This contribution reports on the potential of L-band Permanent Scatterer technique for the detection and monitoring of ground subsidence. We present the use of PS in the abandoned mining area, Korea. Discrete and temporarily stable natural reflectors or permanent scatterers (PS) can be identified from long temporal series of interferometric SAR images. This subset of image pixels can be exploited successfully for high accuracy differential measurements (Ferretti et al., 2000).

• The Korean Journal of Nuclear Medicine
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• v.37 no.1
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• pp.13-23
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• 2003

Neurodegenerative disorders cause a variety of dementia including Alzheimer disease, frontotemporal dementia, dementia with Lewy bodies, corticobasal degeneration, progressive supranuclear palsy, and Huntington's disease. PET scan is useful for early detection and differential diagnosis of these dementing disorders. Also, it provides valuable information about clinico-anatomical correlation, allowing better understanding of function of brain. Here we discuss recent achievements PET studies regarding these dementing disorders. Future progress in PET technology, new tracers, and image analysis will play an important role in further clarifying the disease pathophysiology and brain functions.

• Proceedings of the Korea Information Processing Society Conference
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• 2004.05a
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• pp.719-722
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• 2004

객체 중심점에서 움직임을 추정하고 보상하여 빠르게 움직이는 객체의 윤곽선을 실시간으로 추적 할 수 있는 알고리듬을 제안하였다. 방사상 표현 (radial representation) 방식을 적용하여 객체 중심점에서만 블록정합 (block matching) 알고리듬으로 움직임을 추정하고 보상하여 적은 계산량으로 객체 움직임을 추정하고 보상함으로써 객체 윤곽선을 실시간으로 추적하였다. 에너지 수렴 과정에서 기울기 영상과 차영상 (differential image)을 에너지 함수로 함께 사용함으로 배경 잡영 등에도 강건하도록 하였다. 실험 결과 움직임이 빠른 객체와 배경 잡영 속의 객체도 실시간으로 강건하게 추적함을 확인하였다.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.68 no.2
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• pp.304-309
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• 2019

This paper presents a CMOS RF-to-DC converter for video surveillance disposable IoT applications. It widely harvests RF energy of 3G/4G cellular low-band frequency range by employing a tunable impedance matching network. The proposed converter consists of the differential-drive cross-coupled rectifier and the matching network with a 4-bit capacitor array. The proposed converter is designed using 130-nm standard CMOS process. The designed energy harvester can rectify the RF signals from 700 MHz to 900 MHz. It has a peak RF-to-DC conversion efficiency of 72.25%, 64.97%, and 66.28% at 700 MHz, 800 MHz, and 900 MHz with a load resistance of 10kΩ, respectively.

• Journal of Digestive Cancer Research
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• v.10 no.2
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• pp.56-64
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• 2022

Narrow-band imaging (NBI) is the most widely used image-enhanced endoscopic technique. The superficial microanatomy of gastric mucosa can be visualized when used with a magnifying endoscopy with narrow-band imaging (ME-NBI). The diagnostic criteria for early gastric cancer (EGC), using the classification system for microvascular and microsurface pattern of ME-NBI, have been developed, and their usefulness has been proven in the differential diagnosis of small depressed cancer from focal gastritis and in lateral extent delineation of EGC. Some studies reported on the prediction of histologic differentiation and invasion depth of gastric cancer using ME-NBI; however, its application is limited in clinical practice, and further well-designed studies are necessary. Clinicians should understand the ME-NBI classification system and acquire appropriate diagnostic skills through various experiences and training to improve the quality of endoscopy for EGC diagnosis.

• Imaging Science in Dentistry
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• v.54 no.1
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• pp.105-107
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• 2024

The author herein presents an unusual case of eustachian tube calcification masquerading as loose radiopacities in the temporomandibular joints on a panoramic image, creating a diagnostic challenge. The patient, a 72-year-old woman, presented to the dental service for implant treatment to improve her masticatory function. A cone-beam computed tomography scan was performed and reviewed by a board-certified oral and maxillofacial radiologist. The scan showed no evidence of calcifications in the temporomandibular joints; however, it revealed nodular calcifications within the cartilaginous portion of the eustachian tube bilaterally. Additionally, this report briefly reviews the differential diagnosis of calcified loose bodies in the temporomandibular joint and provides information that needs to be reinforced periodically.

• Journal of the Korean earth science society
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• v.39 no.1
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• pp.46-52
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• 2018

This paper is to study the development of three dimensional Digital Surface Model (DSM) using photogrammetry technique based on self-developed Drone (Unmanned Aerial Vehicle (UAV)). To develop DSM, we selected a study area in Jeju island and took 24 pictures from the drone. The three dimensional coordinates of the photos were made by Differential Global Positioning System (DGPS) surveying with 10 ground control points (GCP). From the calculated three dimensional coordinates, we produced orthographic image and DSM. The accuracy of DSM was calculated using three GCPs. The average accuracy of X and Y was from 8.8 to 14.7 cm, and the accuracy of Z was 0.8 to 12.4 cm. The accuracy was less than the reference accuracy of 1/1,000 digital map provided by National Geographic Information Institute (NGII). From the results, we found that the self-developed drone and the photogrammetry technique are a useful tool to make DSM and digital map of Jeju.

• Journal of Broadcast Engineering
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• v.10 no.4 s.29
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• pp.621-631
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• 2005

To enhance the performance of multi-view sequence CODEC, an efficient disparity vector coding method fur multiview sequences is proposed herein. For higher coding efficiency, we encode the differential vectors acquired by subtracting the original vectors from the predicted ones. To enhance the performance of disparity vector coding, it is essential to predict the disparity vectors accurately. The prediction by this proposed method utilizes the correlation among the multiview images, while conventional methods exploit the correlation among the causal blocks. Experiments were performed fur three different 5 view sequences. We were able to confirm that the proposed method predicts disparity vectors accurately by comparing the entropy and the mean absolute values for differential vectors with conventional methods. Its performance is superior to vector coding methods used in MPEG-4 which uses only a spatial correlation. The proposed method increases the coding efficiency by a factor of $30{\~}45\%$ while preserving image quality.

• Journal of the Korean Society of Marine Environment & Safety
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• v.17 no.2
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• pp.131-136
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• 2011

The furrow calculation and traffic measurement of sailing ship using computer vision are useful methods to prevent maritime accident by predicting the possibility of an accident occurrence in advance. In this paper, sailing ships are recognized using image erosion, differential operator and minimax value, which can be verified directly because the calculated coordinates are displayed on electronic navigation chart. The developed algorithm based on area information of this paper has the advantage which is compared to the conventional radar system focused on point information.