https://scholar.dgist.ac.kr/handle/20.500.11750/10188 2026-04-04T13:58:16Z https://scholar.dgist.ac.kr/handle/20.500.11750/59951 Title: Simple and practical single-shot digital holography based on unsupervised diffusion model Author(s): Park, Seonghwan; Park, Jaewoo; Kim, Youhyun; Moon, Inkyu; Javidi, Bahram Abstract: Single-shot digital holography in Gabor mode offers cost-effective quantitative phase imaging but suffers from the fundamental twin image problem, where real and conjugate images are inherently superimposed, severely limiting phase reconstruction accuracy. Traditional iterative phase retrieval methods require computationally expensive multiple propagations, while off-axis holography demands complex optical setups with precise alignment. We present the first unsupervised diffusion model for automated phase image reconstruction from single-shot in-line holograms, eliminating both twin image artifacts and the need for expensive off-axis configurations. Our framework integrates cycle-consistency and denoising modules to enable training on unpaired hologram-phase image datasets, learning the mapping between low-cost in-line measurements and high-quality phase distributions without requiring labeled data pairs. Comprehensive evaluation on diverse biological specimens demonstrates that our approach significantly outperforms conventional unsupervised methods, achieving superior Peak Signal-to-Noise Ratio (PSNR) and Structural Similarity Index Measure (SSIM) values for both red blood cells and cancer cells. Critically, the model maintains exceptional performance even with limited training data, consistently outperforming supervised learning approaches under data-constrained conditions. The framework exhibits remarkable generalization capabilities, successfully reconstructing phase images from holograms captured at different propagation distances and processing various cancer cell types not included in training data. This computational breakthrough enables accurate, scalable, and hardware-efficient quantitative phase imaging, democratizing access to high-quality phase microscopy for resource-constrained environments while maintaining reconstruction fidelity comparable to complex off-axis systems. © 2025 Elsevier B.V., All rights reserved. 2025-12-31T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/56817 Title: STRONG DISCHARGE PROCESSES BY ATMOSPHERIC PLASMA JET A AY WITHOUT EXTERNAL GROUND ELECTRODE Author(s): Kim, Jae Young; Lee, Sun Young; Shin, Mi Hyang; Moon, Dae Won; Tae, Heung-Sik Abstract: We previously reported an intense plasma emission formed by plasma jet-to-jet coupling from various circular array configurations at atmospheric pressure 1,2 . To achieve an intense plasma emission using plasma jet-to-jet coupling, the plasma array device required a single electrode configuration and external ground electrode located several centimeters apart from the array 1 . In spite of an intense plasma plume with a lot of reactive radicals in ambient air, the requirement of precise adjustment of the discharge distance between the plasma array and the counter electrode would be a drawback of the plasma jet array for various surface treatments at atmospheric pressure. To generate an intense plasma plume with a good stability regardless of the discharge distance, we now propose two different plasma array structures to eliminate a counter ground electrode.The first plasma array device consists of a central glass tube encircled by an array of hollow glass tubes with side openings. The device configuration forces the individual plasma jets emanating from the side openings of the outer tubes to merge with the central plasma plume. As a result, a high intensity plasma emission is stably produced from the plasma jet-to-jet coupling of the ten glass tubes regardless of the distance between the plasma array and the external ground electrode, thereby eliminating the need for an external ground electrode. The second proposed plasma array structure consisting of two plasma jet arrays with an appropriate angle and a double electrode configuration is used as an ambient plasma source. Since these proposed plasma devices are able to generate an intense plasma emission without external ground electrode, they are promising tools for surface treatments and modifications that require a strong discharge process such as an ambient ionization mass spectrometry, regardless of the dielectric property of the target material. 2015-05-23T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/47276 Title: 대기압 질량분석 이미징 기술을 위한 나노입자를 이용한 레이저 탈착 성능 향상 Author(s): 김재영; 서은석; 문대원 2017-02-14T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/46625 Title: 세포의 약물 반응을 측정하는 3차원 이미징 및 영상 처리 장치 및 방법 Author(s): 문인규; 케이반 자퍼자데; 김유현 Abstract: 본 개시의 일 실시 예에 따른 컴퓨팅 장치의 세포 약물 반응 측정 방법은 약물 처리된 제1 심근 세포에 대한 디지털 홀로그래픽 영상인 심근 세포 홀로그램을 제공 받는 단계, 프로세서에 의해 심근 세포 홀로그램에 대해 재건(reconstruction) 및 위상 펼침(phase unwrapping)을 수행하고, 복수의 심근 세포 영상을 생성하는 단계, 프로세서에 의해 심근 세포 영상에 기반하여 제1 심근 세포의 기계 운동학적 특성 또는 박동과 관련된 적어도 하나의 제1 동적 파라미터를 획득하는 단계 및 프로세서에 의해 약물 처리되지 않은 제2 심근 세포에 기반하여 획득된 제2 동적 파라미터를 제1 동적 파라미터와 비교하는 단계를 포함할 수 있다.