• 한국농공학회지
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• 제18권1호
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• pp.4038-4051
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• 1976

This study was intended to provide the basic design creteria for the refrigerated storage, and to estimate the required optimum capacity of refrigerator for the different sizes and kinds of the existing fruit storage. The structural characteristics of the existing fruit storages in Pyungtaek-khun of Kyungki-do were surveyed. The average out-door air temperature during the expected storage life after harvesting, was obtained by analyzing the weather information. The heat transfer rates through the different models of storage walls were estimated. The refrigerating load required for different models of fruit storage was analyzed in the basis of out-door air temperature. The results obtained in this study are summarized as follows: 1. The fruit storages surveyed were constructed on-ground, under-ground and sub-ground type buildings. The majority of them being the on-ground buildings are mostly made of earth bricks with double walls. Rice hull was mostly used as the insulating materials for their walls and ceilings. About 42% of the buildings were with the horizontal ceiling, 22% with sloped ceiling, and about 36% without ceiling. About 60% of the storage buildings had floor without using insulated material. They were made of compacted earth. 2. There is no difference in heat transfer among six different types of double walls. The double wall, however, gives much less heat transfer than the single wall. Therefore, the double wall is recommended as the walls of the fruit storage on the point of heat transfer. Especially, in case of the single wall using concrete, the heat transfer is about five time of the double walls. It is evident that concrete is not proper wall material for the fruit storage without using special insulating material. 3. The heat transfer through the storage walls is in inverse proportion to the thickness of rice hull which is mostly used as the insulating material in the surveyed area. It is recommended that the thickness of rice hull used as the insulating material far storage wall is about 20cm in consideration of the decreasing rate of heat transfer and the available storage area. 4. The design refrigerating load for the on-ground storages having 20 pyung area is estimated in 4.07 to 4.16 ton refrigeration for double walls, and 5.23 to 6.97 ton refrigeration for single walls. During the long storage life, however, the average daily refrigerating load is ranged from 0.93 to 0.95 ton refrigeration for double walls, and from 1.15 to 1.47 ton refrigeration for single walls, respectively. 5. In case of single walls, 50.8 to 61.4 percent to total refrigerating load during the long storage life is caused by the heat transferred into the room space through walls, ceiling and floor. On the other hand, 39.1 to 40.7 percent is for the double walls. 6. The design and average daily refrigerating load increases in linear proportion to the size of storage area. As the size increases, the increasing rate of the refrigerating load is raised in proportion to the heat transfer rate of the wall. 7. The refrigerating load during the long storage life has close relationship to the out-door air temperature. The maximum refrigeration load is shown in later May, which is amounted to about 50 percent to the design refrigerating load. 8. It is noted that when the wall material having high heat transfer rate, such as the single wall made of concrete, is used, heating facilities are required for the period of later December to early February.

• 한국수산과학회지
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• 제15권3호
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• pp.241-250
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• 1982

자웅동체형 이매패인 새조개, Fulvia mutica,의 자원관리 및 양식을 위한 기초생물학적 연구로서, 1980년 10월부터 1981년 9월까지 월별로 채집한 여수근해산 재료를 대상으로 생식세포형성과정 및 생식월파를 조직학적 방법에 의해 제사하였다. 생식소는 복잡한 관상구조를 가진 않은 난소소낭과 정소소낭들이 서로 혼재된 자웅동체형을 나타내고 있다. 발달초기의 생식소에서 성장중인 생식세포와 함께 호산성 과립세포와 불분화간충조직들이 풍부하게 나타나고 있으며, 생식소 성숙함에 따라 점차 소실되어 간다. 완숙난의 크기는 $56\sim67{\mu}m$으로 젤라틴장의 피막에 둘러싸여 있고, 변태를 마친 완숙정자는 청소소의 내경신앙에 파상의 정자수을 형성한다. 새조채의 생식주기는 분열증식기, 성장기, 성숙기, 방출기, 퇴화기 및 회복기의 연연시인 6단계로 나눌 수 있었으며, 산난기는 수온 $20^{\circ}C$내외의 $5\sim10$월로써, 그 성기는 $6\sim7$과 9월인 것으로 나타났다. 특히, 5월의 조기산난개체들은 생식소를 곧 회복발달시켜 9, 10월 방난군에 다시 참여하는 것으로 추정되었다.