간행물
수산해양기술연구 KCI 등재 Journal of the Korean Society of Fisheries and Ocean Technology 韓國漁業技術學會誌
- 발행기관 한국수산해양기술학회(구 한국어업기술학회)
- 자료유형 학술지
- 간기 계간
- ISSN 2671-9940 (Print)2671-9924 (Online)
- 수록기간 1965 ~ 2024
- 주제분류 농수해양 > 수산학 농수해양 분류의 다른 간행물
- 십진분류KDC 529DDC 639
권호리스트/논문검색
권호
51권 3호 (2015년 8월) 22건
21.
2015.08
구독 인증기관 무료, 개인회원 유료
The present study is undertaken to evaluate the effect of volume fraction on the results of Charpy impact test for the rubber matrix filled with nano sized silica particles composites. The Charpy impact tests are conducted in the temperature range 0°C and –10°C. The range of volume fraction of silica particles tested are between 11% to 25%. The critical energy release rate GIC of the rubber matrix composites filled with nano sized silica particles is affected by silica volume fraction and it is shown that the value of GIC decreases as volume fraction increases. In regions close to the initial crack tip, fracture processes such as matrix deformation, silica particle debonding and delamination, and/or pull out between particles and matrix which is ascertained by SEM photographs of Charpy impact fracture surfaces.
4,000원
22.
2015.08
구독 인증기관 무료, 개인회원 유료
Jinhae Bay located in the southern of Korean Peninsular is an important spawning area in Korea. By some preliminary studies it was measured several times that adult Pacific codes (Gadus microcephalus) were passed (swimming layer: 15 to 18 m) over a submerged sea tunnel (sea bottom: about 30 m) rather than another immigration route when the Pacific codes were tagged surgically with an acoustic transmitters and released inside of the Bay. There is a possibility that the Pacific codes and the other fishes use the route on the sea tunnel as an immigration route are affected by a human–generated underwater noise around the sea tunnel due to the sea tunnel traffic. On this study the 25–hour measurements of the underwater noise level by water layer were conducted with a hydrophone attached on a portable CTD and an underwater noise level meter during four seasons, and the acoustical characteristics of the underwater noise was analyzed. The mean traffic volume for one hour at the sea tunnel on the spring was shown the largest value of 1,408 [standard deviation (SD): 855] vehicles among four seasons measurement. The next one was ordered on the autumn [1,145 (SD: 764)], winter [947 (SD: 598)] and summer [931 (SD: 558)] vehicles. Small size vehicle was formed 84.3% of the traffic volume, and ultra–small size, medium size, large size and extra–large size of the vehicle were taken possession of 8.7%, 3.2%, 2.0% and 1.8%, respectively. On the daily change of the noise level in vertical during four seasons the noise level of 5 m–layer was shown the highest value of 121.2 (SD: 3.6) dB (re 1 μPa), the next one was 10 m– layer [120.7 (SD: 3.5)], 2 m– and 15 m–layer [120.3 (SD: 3.5 to 3.7)] and 1 m–layer [119.2 (SD: 3.6)] dB (re 1 μPa). In relation with the seasonal change of the noise level the average noise level measured during autumn was shown the highest value of 123.9 (SD: 2.6) dB (re 1 μPa), the next was during summer [121.4 (SD: 3.2)], spring [118.0 (SD: 3.4)] and winter [116.5 (SD: 5.1)] dB (re 1 μPa). In results of eigenray computation when the real bathymetry data (complicate shape of sea bed) was applied the average number of eigenray was 2.68 times (eigenrays: 11.03 rays) higher than those of model bathymetry (flat and slightly sloped sea bottom). When the real bathymetric data toward inside (water depth becomes shallow according to a distance between the source of noise and hydrophone) of the Bay was applied on the eigenrays calculation the number of the eigenray was 1.31 times (eigenrays: 12.49 rays) larger than the real bathymetric data toward outside (water depth becomes deep with respect to the distance). But whenthe model bathymetric data toward inside of the Bay was applied the number of the eigenray was 1.05 times (eigenrays: 4.21 rays) larger than the model bathymetric data toward outside.
4,500원
1
2
