https://scholar.korea.ac.kr/handle/2021.sw.korea/776 Wed, 08 Apr 2026 12:07:36 GMT 2026-04-08T12:07:36Z https://scholar.korea.ac.kr/handle/2021.sw.korea/269278 Title: Nondestructive methodology with discerning fruit freshness biomarker compounds using olfactory receptor nanodisc-loaded graphene transistors Authors: Seo, Sung Eun; Cho, Seongyeon; Kim, Kyung Ho; Lee, Seongbin; Lee, Jiwon; Cha, Yeon Kyung; Ryu, Yong-Sang; Park, Tai Hyun; Song, Hyun Seok; Kwon, Oh Seok Abstract: Noninvasive and facile methodologies for the assessment of fruit freshness are essential for the determination of fruit ripeness. Fruits emit characteristic aroma molecules during maturation, and the selective and sensitive detection of these scents is highly challenging. Herein, a novel nondestructive methodology for discerning fruit freshness biomarker compounds based on a target-specific olfactory receptor-loaded transistor for detecting aroma molecules at ppb levels is proposed. This fruit freshness discrimination platform can detect the representative aromas caused by compounds including iso-amyl acetate, amyl-butyrate, geraniol, and beta-citronellol that are emitted by each fruit species, such as bananas, grapes, and apricots, and has a lower limit of detection below femtomolar concentrations. Measurement of the selective binding affinity between the olfactory receptor and aroma molecules was conducted using biosimulation, and the experimental results were compared with the sensor response. The fabricated sensor exhibited superior performance in determining the ripeness of fruits with discerning fruit freshness biomarker compounds and presented promising potential for application in agriculture and other industry fields as an assessment platform for detecting various aromatic molecules. Our findings highlight the broad utilization of newly developed sensor platforms as standards for distinguishing freshness. Fri, 01 Aug 2025 00:00:00 GMT https://scholar.korea.ac.kr/handle/2021.sw.korea/269278 2025-08-01T00:00:00Z https://scholar.korea.ac.kr/handle/2021.sw.korea/269332 Title: Gamma-ray detection using Cs3Cu2I5 perovskite scintillator crystals grown by fast inverse temperature crystallization Authors: Park, Chansun; Melis, Alima; Kim, Sangsu; Song, Seungho; Seo, Jiwon; Cho, Shinhaeng; Yeom, Jung-Yeol Abstract: Metal-halide perovskite crystals have garnered attention as next-generation, highly efficient radiation detectors across various applications owing to their scintillation properties and competitive optical performance. In this study, we examined the gamma-ray detection performance of a Cs3Cu2I5 single crystal grown within three days using the inverse temperature crystallization method. Formic acid was used to prevent I-and Cu-ion oxidation and thus obtain samples of suitable sizes, cleaned with dimethyl sulfoxide and dimethylformamide to optimize sample conditions, for gamma-ray detection. A 10 x 10 x 6 mm3 Cs3Cu2I5 scintillator sample was wrapped with Teflon tape and coupled to a photomultiplier tube with an optical pad to measure energy spectra. Energy resolutions of 9.2 % and 12.5 % were detected for 137Cs and 22Na radioactive sources, respectively, and optical-performance evaluation revealed transmittances of 76.2 % and 73.3 %, near 440 nm, for two (10 x 10 x 6 and 5 x 5 x 4 mm3, respectively) Cs3Cu2I5 scintillator samples. These results confirm the competitive detection and optical performances of the fabricated scintillator. This study offers promising results and valuable insights for overcoming challenges in future research, including bulk crystal growth of Cs3Cu2I5 through a rapid method for use in high-radiation and high-temperature environments. Tue, 01 Jul 2025 00:00:00 GMT https://scholar.korea.ac.kr/handle/2021.sw.korea/269332 2025-07-01T00:00:00Z https://scholar.korea.ac.kr/handle/2021.sw.korea/269341 Title: Development of a drone-mounted remote radiation imaging system Authors: Lee, Inbum; Park, Youngjoo; Seo, Donghui; Jeon, Kangwoo; Jeong, Jaewon; Jeong, Manhee; Moon, Jinho; Jung, Sung-Hee; Yeom, Jung-Yeol; Lee, Hakjae; Lee, Kisung Abstract: The imperative need for real-time systems to monitor radioactive materials cannot be overstated, as they play a pivotal role in mitigating accidents involving radioactive materials. Additionally, with increasing safety awareness regarding radiation exposure, there is growing focus on the development of mobile unmanned systems. This study aims to develop a fully integrated drone-based radiation imaging system. The proposed system comprises a custom, compact, and lightweight gamma-ray detector module designed to be mounted as a payload on a commercial drone, a long-range data transmission module utilizing a dedicated drone network, and a software module for gamma-ray spectrum analysis and monitoring. The detector module, weighing approximately 530 g, can be integrated with the drone via a gimbal, enabling real-time data transmission through the drone network. Experimental results demonstrate the feasibility of the proposed system for real-time remote radiation monitoring, achieving an angular resolution of 7-10 degrees and an operational range exceeding 1.2 km, with a maximum data transmission speed of up to 15,000 counts per second. Thu, 01 May 2025 00:00:00 GMT https://scholar.korea.ac.kr/handle/2021.sw.korea/269341 2025-05-01T00:00:00Z https://scholar.korea.ac.kr/handle/2021.sw.korea/268545 Title: Optimization of electrode position in electric field treatment for pancreatic cancer Authors: Kim, Sangcheol; Ko, Yousun; Shin, Dongho; Kim, Haksoo; Lee, Sung Uk; Kim, Jonghyun; Kim, Tae Hyun; Yoon, Myonggeun Abstract: BackgroundIn electric field-based cancer treatment, the intensity of the electric field applied to the tumor depends on the position of the electrode array, directly affecting the efficacy of treatment. The present study evaluated the effects of changing the position of the electrode array on the efficacy of electric field treatment for pancreatic cancer.MethodsA 3D model was created based on computed tomography images of 13 pancreatic cancer patients. An electrode array was placed on the surface of the model at various positions, and the electric field was calculated for each. Six treatment plans were created for each patient by rotating each electrode array +/- 15 degrees, +/- 30 degrees in the axial plane, and +/- 10 degrees in the sagittal plane relative to the reference plan. The frequency was set at 150 kHz and the current density at 31 mArms/cm2 for calculation of all treatment plans. The mean electric field, minimum electric field, homogeneity index (HI) and coverage index (CI) calculated from the six simulated plans were compared with the reference plan to evaluate the effects of each simulated plan on the tumor.ResultsComparisons of the simulated plans for each patient with the reference plan showed differences of -2.61 similar to 11.31% in the mean electric field, -7.03 similar to 13.87% in the minimum electric field, -64.14 similar to 13.12% in the HI, and - 24.23 similar to 11.00% in the CI. Compared with the reference plan, the optimal plans created by changing the electrode position improved the mean electric field 7.41%, the minimum electric field 7.20%, the HI 4.57%, and the CI 8.46%.ConclusionsUse of a treatment planning system to determine the optimal placement of the electrode array based on the anatomical characteristics of each patient can improve the intensity of the electric field applied to the tumor. Fri, 04 Apr 2025 00:00:00 GMT https://scholar.korea.ac.kr/handle/2021.sw.korea/268545 2025-04-04T00:00:00Z