• Journal of Astronomy and Space Sciences
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• 제23권3호
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• pp.289-302
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• 2006

조선초기 세종대에 제작하여 사용한 규표를 복원하기위해 '세종실록'을 비롯한 조선시대의 문헌자료를 수집하여 원리와 구조를 분석하였다. 그리고 이를 근거로 1/10로 축소 모형을 제작하고 설계도를 완성하였다. 규표의 구조는 규(圭), 용표(龍表), 횡량(橫梁), 또는 들보), 받침대로 구성되어 있다. 수직으로 세운 막대인 용표의 그림자가 수평으로 놓인 규면에 맺힐 때 눈금을 읽으면 된다. 이때 그림자 중심에 태양의 상을 맺히게 하는 영부를 사용하여 정밀하게 측정한다. 영부는 가운데 바늘구멍을 뚫은 작은 동판을 사용하여 바늘구멍 사진기와 샤임프러그 원리를 이용하여 태양의 영상을 맺히도록 한다.

• Entomological Research
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• 제48권6호
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• pp.550-558
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• 2018

To develop a system for the mass production of Protaetia brevitarsislarvae (Pbl), this study analyzed the oviposition characteristics of third instar Pbl through successive rearing and cold treatments. In the first generation, females laid 50 eggs each on average, and spawned higher numbers of eggs for the first 5 days but then fewer after this. However, all of the $2^{nd}$-generation females that were produced through the successive rearing of eggs from the $1^{st}$ generation did not spawn. When test insects (TI) were raised at $32^{\circ}C$, their $mean{\pm}SE$ pupal period and emergence rate were $28.4{\pm}1.9$ days and 87%, respectively. However, most individuals raised in cold treatments ($5^{\circ}C$ and $-5^{\circ}C$) without a pre-cooling period did not survive. Individuals exposed to a pre-cooling period, however, had a 7-10 days longer pupal period than those raised at $32^{\circ}C$, and their emergence rate (90%) was slightly higher. Different cold treatment temperatures ($0^{\circ}C$, $3^{\circ}C$, or $5^{\circ}C$) and periods (30 or 60 days) were tested in further experiments. The experimental group kept for 30 days at $0^{\circ}C$ and $3^{\circ}C$ had the shortest pupal period of all, and emergence rates exceeded 90% in most groups. With respect to the number of eggs spawned by the second generation females after cold treatments, the experimental groups held in cold treatments at $5^{\circ}C$ for 30 and 60 days were found to spawn the most eggs. Consequently, the experimental group kept at $5^{\circ}C$ for 30 days was the most effective set of conditions tested during the entire breeding period.