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농작물 병해충 진단을 위한 인공지능 앱, Dr. Vegetable (Dr. Vegetable: an AI-based Mobile Application for Diagnosis of Plant Diseases and Insect Pests)

  • 김수환;정대기;이승준;정성엽;양동재;정근영;황석형;황세웅
    • 한국컴퓨터정보학회:학술대회논문집
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    • 한국컴퓨터정보학회 2023년도 제67차 동계학술대회논문집 31권1호
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    • pp.457-460
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    • 2023
  • 본 연구는 시설작물의 병충해 진단을 위해 딥러닝 모델을 응용한 인공지능 서비스 앱, Dr. Vegetable을 제안하고자 한다. 농업 현장에서 숙련된 농부는 한눈에 농작물의 병충해를 판단할 수 있지만 미숙련된 농부는 병충해 피해를 발견하더라도 그 종류와 해결 방법을 찾아내기가 매우 어렵다. 또한 아무리 숙련된 농부라고 할지라도 육안검사만으로 병충해를 조기에 발견하는 것은 쉽지 않다. 한편 시설작물의 경우 병충해에 의한 연쇄피해가 발생할 우려가 있으므로 병충해의 조기 발견 및 방제가 매우 중요하다. 즉, 농부의 경험에 따른 농작물 병해충 진단은 정확성을 장담할 수 없으며 비용과 시간적인 측면에서 위험성이 높다고 할 수 있다. 본 논문에서는 YOLOv5를 활용하여 상추, 고추, 토마토 등 농작물의 병충해를 진단하는 인공지능 서비스를 제안한다. 특히 한국지능정보사회진흥원이 운영하고 있는 AI 통합 플랫폼인 AI 허브에서 제공하는 노지 작물 질병 및 해충 진단 이미지를 사용하여 딥러닝 모델을 학습하였다. 본 연구를 통해 개발된 모바일 어플리케이션을 이용하여 실제 시설농장에서 병충해 진단 서비스를 적용한 결과 약 86%의 정확도, F1 Score 0.84, 그리고 0.98의 mAP 값을 얻을 수 있었다. 본 연구에서 개발한 병충해 진단 딥러닝 모델을 다양한 조도에서 강인하게 동작하도록 개선한다면 농업 현장에서 널리 활용될 수 있을 것으로 기대한다.

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Dating Sun's Locations at Equinoxes Inscribed on Cheonsang Yeolcha Bunyajido

  • Sang-Hyeon Ahn
    • 천문학회지
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    • 제56권2호
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    • pp.201-212
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    • 2023
  • The inscription of Cheonsang Yeolcha Bunyajido (天象列次分野之圖) has the sun's locations at the equinoxes, which must have been copied from the astronomical treatises in Chinese historical annals, Songshu (宋書) and Jinshu (晉書). According to the treatises, an astronomer Wang Fan (王蕃, 228-266 CE) referred those values from a calendrical system called Qianxiangli (乾象曆, 223 CE), from which it is confirmed that it adopted the sun's location at the winter solstice of the $(21{\frac{1}{4}})^{th}$ du of the 8th lunar lodge Dou (斗) as the reference direction for equatorial lodge angles. This indicates that the sun's locations at equinoxes and solstices in the calendrical system are the same as those in Jingchuli (景初曆, 237 CE). Hence, we propose that the sun's location at the autumnal equinox in Cheonsang Yeolcha Bunyajido should be corrected from 'wu du shao ruo' (五度少弱), meaning the $(5{\frac{1}{6}})^{th}$ du, to 'wu du ruo' (五度弱), meaning the $(4{\frac{11}{12}})^{th}$ du, of the first lunar lodge Jiao (角), as seen in Jingchuli. We reconstruct the polar coordinate system used in circular star charts, assuming that the mean motion rule was applied and its reference direction was the sun's location at the winter solstice. Considering the precession, we determined the observational epoch of the sun's location at the winter solstice to be to = -18.3 ± 43.0 adopting the observational error of the so-called archaic determinatives (古度). It is noteworthy that the sun's locations at equinoxes inscribed in Cheonsang Yeolcha Bunyajido originated from Houhan Sifenli (後漢 四分曆) of the Latter Han dynasty (85 CE), while the coordinate origin in the star chart is related to Taichuli (太初曆) of the Former Han dynasty (104 BCE).

Design and simulation of 500 MHz single cell superconducting RF cavity for SILF

  • Yanbing Sun;Wei Ma;Nan Yuan;Yulin Ge;Zhen Yang;Liping Zou;Liang Lu
    • Nuclear Engineering and Technology
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    • 제56권1호
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    • pp.195-206
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    • 2024
  • Shenzhen Innovation Light source Facility (SILF) is a 3.0 GeV fourth generation diffraction limited synchrotron light source currently under construction in Shenzhen. The SILF storage ring is proposed to use two 500 MHz single cell superconducting radio frequency (SRF) cavities to provide 2.4 MV RF voltage. In this study, we examined the geometric structure of mature CESR superconducting cavities and adopted a beam-pipe-type extraction scheme for high-order modes (HOM). One of the objectives of SRF cavity design and optimization in this study is to reduce Ep/Eacc and Bp/Eacc as much as possible to reduce power loss and ensure stable operation of the cavity. To reduce the risk of beam instability and thermal breakdown, the HOM and Multipacting (MP) are simulated. Moreover, the mechanical properties of the cavity are analyzed, including frequency sensitivity from pressure of liquid helium (LHe), stress, tuning, Lorentz force detuning (LFD), the microphone effect, and buckling. By comprehensive design and optimization of 500 MHz single-cell SRF cavities, a superconducting cavity for SILF storage ring was developed. This paper will detailed present the design and simulation.

Biosynthesis of Deoxysugar and New Antibiotics

  • Sohng, Jae-Kyung;Lee, Hei-Chan;Kwangkyoung, Kwangkyoung Liou;Woo, Jin-Suk;Kim, Byung-Gee
    • 한국미생물생명공학회:학술대회논문집
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    • 한국미생물생명공학회 2003년도 2003 Annual Meeting, BioExhibition and International Symposium
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    • pp.123-123
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    • 2003
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