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Yong-Dea Yun;Hyun-Ok Choi;Jong-Hoon Lee
- KOREAN JOURNAL OF CROP SCIENCE
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- v.22 no.2
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- pp.32-36
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- 1977
Experiments were conducted to know the effects of seed bed temperatures on the sprouting of seeds and seedling growth in the phytotron and field. Sprouting of seeds were most uniform when seed bed was stored under the straw and vinyl mulching for 48 hours after seed bed temperature increased up to 3$0^{\circ}C$ by the sun. In the phytotron, optimum temperature was 32$^{\circ}C$ for sprouting and day/night temperature of 25/30 and 20/15$^{\circ}C$ for greening and hardening of seedlings, respectively. In the field, the best results were obtained under the conditions of sprouting in the seedling chamber heated by electricity and greening the hardening under the double vinyl tunnel in the upland nusery bed.
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이상룡;문동준;전호경
- Journal of Korean Society of Coastal and Ocean Engineers
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- v.8 no.1
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- pp.10-17
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- 1996
A real time simple DGPS (SDGPS) for coastal survey is developed and in situ tested. While the accuracy of the system is almost the same as that of existing commercially available DGPS, it is very economical compared to the commercial ones. The RMS error of the positions fired by the system is estimated to be less than 2 m within the range of 30 km from the reference station. Even if the coordinates of the reference station are uncertain, they can be fixed, from the continuous GPS observation of one day, with the maximum error less than 1 m. The system is believed to be helpfully utilized to most of coastal surveys despite of some minor defects.
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이희명;정두영
- Journal of Korean Society of Coastal and Ocean Engineers
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- v.6 no.1
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- pp.23-33
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- 1994
Liquefaction characteristics of the reclaimed marine sand deposits is studied by means of the dynamic response analysis and the cyclic triaxial compression test. 1) From the result of the dynamic response analysis. it was found that the amplification of ground surface maximum acceleration varied with input earthquake motions and soil data, and earthquake coefficients were proposed to be applicable in evaluating liquefaction potential by simplified prediction methods. 2) For upper and soft sand deposits with small N-value, liquefaction strengths estimated by Seed and Idriss's simplified method were lower than those by the cyclic triaxial test while those by Iwasaki & Tatsuoka's or Vs-method were not lower. 3) Simplified methods were inclined to overestimate liquefaction potential in comparison with the dynamic response analysis and the cyclic triaxial compression test Allowable depths of liquefaction(safety factor 1) were estimated to be 7-14m for 0.1 -0.2g of input maximum acceleration.
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김중규;강만종;김영훈;장덕지;강민수;김승호
- Korean Journal of Animal Reproduction
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- v.12 no.2
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- pp.84-90
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- 1988
This study was done with mouse embryos to determine effects of the freezing media with or without 10% sucrose, and seeding methods (pincette, no seeding, liquid nitrogen gas phase and copper wire coiled straw) on embryo survival were determined using the FDA test. The summarized results are the following. 1. The FDA score found with copper wire coiled straw, no seeding, pincette and liquid nitrogen gas phase was 3.6, 3.6, 3.3 and 3.0, respectively. There were no significant differences. 2. The embryo score shows higher (P<0.05) survival rate using a freezing medium with sucrose than the one without it. Among the seeding procedure, better resutls are copper wire coiled straw and no seeded. 3. The results suggest that copper wire coiled seeding no seeding be as good as seeding when the mouse embryos were frozen in a liquid nitrogen container using both the freezing and dilution media containing 10% sucrose.
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