간행물

수산해양기술연구 KCI 등재 Journal of the Korean Society of Fisheries and Ocean Technology 韓國漁業技術學會誌

권호리스트/논문검색
이 간행물 논문 검색

권호

52권 1호 (2016년 2월) 10

1.
2016.02 구독 인증기관 무료, 개인회원 유료
In this study, numerical method was used to assess technical properties and improve the Vietnamese tuna purse seine. Thedata were extracted from the two national level projects. The study results showed that average lead-line sinking speed reached 0.139 m/s and 0.143 m/s and maximum sinking depth was 61.6 m and 65.8 m for The gears 2003 and 2014 respectively. The maximum tension on ring line of The gear 2003 was 4,742 kgf and 2014 was 4,219 kgf. The improved tuna purse seines I, III and IV showed similar sinking speed results with 0.220 m/s, 0.219 m/s and 0.219 m/s respectively. The average lead-line sinking speed of the improved gear II was lowest with 0.215 m/s. The maximum lead-line sinking depth of the four improved gears I, II, III and IV were 116 m, 112 m, 115 m and 114.9 m respectively. Maximum tension on ring line of the improved gears I, II, III and IV were 5,657 kgf, 5,406 kgf, 5,645 kgf and 5,654 kgf respectively. The improved tuna purse seine IV is the most suitable for Vietnamese tuna purse seine fishery, Which corresponds with tuna purse seiner scale and its fishing supporting equipment at the present.
4,000원
2.
2016.02 구독 인증기관 무료, 개인회원 유료
This study was conducted to analyze fishing capacity and bycatch by mesh size and entrance size of spring net pot conductedby water tank and field experiment. The water tank experiments were conducted by using traps with mesh size of 22 mm and entrance size of 120 mm and 140 mm, respectively in the water tank of NIFS. The field experiment was conducted using 5 kinds of spring net pot with mesh sizes of 20 mm, 22 mm, 35 mm and entrance size of 120 mm, 130 mm, 140 mm, 360 mm by coastal trap fishery vessel operating around the area of Geoje island. In the result of water tank experiments, the catch of conger eel was 1.5 times higher when using trap with entrance size of 140 mm than that of 120 mm. In the field experiment, when using same mesh size, the larger the entrance size, the higher amount of conger eel catch, bycatch and number of bycatch species. When using the same entrance size, the larger the mesh size, the lower amount of conger eel catch and number of bycatch species, whereas the amount of bycatch showed increasing trend.
4,000원
3.
2016.02 구독 인증기관 무료, 개인회원 유료
This study investigates the development of an automatic lightening buoy that can indicate an aquaculture cage at night or in rough weather. The energy for the light is generated by the linear motion of a magnet along with a coil inside the buoy as the waves cause the buoy to oscillate up and down. The principle of the magnet motion is different between the magnet and body of the buoy because the movement of the latter is dependent on the surface wave, while the former is affected by the damper. To obtain a quantitative performance of the buoy, the voltage as well as up and down motion produced by several waves were measured in the wave tank. A shorter wave period, i.e., faster motion, of the magnet produced a brighter light. It is expected that this study can aid in deciding the optimum design of a buoy capable of producing a bright light at any aquaculture site affected by sea or fresh water waves.
4,000원
4.
2016.02 구독 인증기관 무료, 개인회원 유료
An acoustic and trawl pilot survey using a small vessel was conducted in Jinhae bay of the South Sea of South Korea on April 13~14, May 11~13 and June 8~10, 2015. During the survey, acoustic data was collected and bottom trawls were conducted at the same time. First, various noises were eliminated by using the Park method based on the Wang method(Wang et al., 2015; Park et al., 2015), the species compositions and catch rate from each bottom trawl were observed, and spatial distribution of fishery resources in the water column and their nautical area scattering coefficient (NASC) were investigated through acoustic data. During the entire survey period, 12 orders, 33 families and 41 species were caught. The most caught species in April, May and June were Okamejei kenojei, Zoarces gilli and Pholis nebulosa, respectively. Fish schools were observed near the line of net mouth height in April. Numerous weak scatters were presented on the echograms in May and June. Many fish schools appeared in between the water surface and 20 m deep in May. The NASC value from entire water columns was the lowest in April (35.9 m2/n・mile2) and highest in June (1541.3 m2/n・mile2).
4,300원
5.
2016.02 구독 인증기관 무료, 개인회원 유료
Changes in target strength (TS) values of sandfish when sandfish was alive and dead were investigated using ex-situ at120 kHz. TS values measured by tilt angles with ‑50∼+50 degrees showed ranges from ‑71.0 to ‑53.3 dB for live sandfish, ‑63.1~‑46.3 dB for thawed sandfish, and ‑70.0~‑50.4 dB after 24 hours from thawed, respectively. It was shown that while TS values were similar between the case of live and the case of after 24 hours from thawed, mean TS values were higher by approximately 5 dB in the case of immediate thawed sandfish. It was also seen that TS values were similar between the case of thawed sandfish and the case of after 21 hours from live. The results showed that TS values of live sandfish were different from those of frozen sandfish. It implies that when estimating TS of frozen fish, the influx of bubbles and changes of body should be considered.
4,000원
6.
2016.02 구독 인증기관 무료, 개인회원 유료
This study was conducted to investigate visual threshold of nigro (Cichlasoma nigrofasciatum) on white LED light. Thevisual threshold was obtained by analyzing electrocardiogram (ECG) of the nigro. 5 individuals (body weight: 15.62~45.49 g; TL: 8.9~12.4 cm) were trained for lights by an electric stimulus. And then the heart rate (beats/10s) before and after switching on the light were compared. Light intensity range was from 0.00 to 226.4 lux. Average heart rate was 10.36 beats/10s in the normal condition. When the fish perceived the light, the heart rate was decreased. Visual threshold of the fish was 2.59 lux.
4,000원
7.
2016.02 구독 인증기관 무료, 개인회원 유료
The species composition and distribution of catches by dredge gear in the Yeongil Bay, Korea were investigated on aseasonal basis from February to November, 2015. Total catches consisted of 44 species and 35 families. They were 13 species of fish, 10 species of crustacea, 5 species of echinodermata, 5 species of gastropoda, 4 species of cephalopoda and 3 species of bivalvia. Major catch species was shellfish and had seasonal variations in catch. In spring and winter, the catch of ark shell (Scapharca broughtonii) was increased. Adversely, the catch of admas venus clam (Callithaca adamsi) increased in sunmmer and autumn. Species diversity indices was high as the value of 1.99 in spring, and low to the value of 0.34 in summer. In addition, multi dimentional scaling (MDS) indices also was high in spring as the value of 1.99. In summer, the index was low as the value of 0.34. Similarity analysis based on species data was transformed by fourth root. With the result of cluster analysis and MDS analysis, species was divided into two groups. The first group as Group A consists of winter and spring species and another was Group B made of species in summer and winter.
4,000원
8.
2016.02 구독 인증기관 무료, 개인회원 유료
This study analyzed characteristics of officers’ watch-keeping during fishing operation at the fisheries training ship KAYA(GT: 1,737 tons, Pukyong National University). It observed fishing works of three officers in wheel house of KAYA. The observations were carried out at the fishing ground 45 miles away from east of Jeju from 7 to 8 January 2010. The works and movements of the officers were recorded with three common video cameras and a 4-channel MPEG-4 Triplex DVR. Recorded data of the working circulation was analyzed by using the post-processing method. As a result of the traffic lines, the average (±S.D) of working hour (min) and moving frequency (times), distance (m) and speed (m/min) during setting the net was 11.8 (0.9), 43.7 (8.1), 133.9 (35.8) and 10.5 (0.6), respectively. During trawling the net, it was 100, 241 (39.8), 615.7 (194.6) and 5.2 (1.6), respectively. During hauling the net, it was 17.6 (1.4), 41.0 (7.2), 196.9 (37.6) and 10.7 (0.8), respectively. In addition, it has a different tendency of the instrument usage frequency by the fishing works. During setting, the usage priority was CCTV, ECDIS, RPM and pitch controller, net monitor, GPS plotter, chart room, X-band radar, fish finder and public addressor. During trawling, it was CCTV, ECDIS, fish finder, X-band radar, net monitor, chart room, GPS plotter, RPM and pitch controller, auto pilot and steering, interphone, wind speed and direction indicator, No.1. VHF, navigation light control panel and public addressor. During hauling, it was CCTV, RPM and pitch controller, GPS plotter, public addressor, chart room, net monitor, X-band radar, auto pilot and steering and fish finder.
4,000원
9.
2016.02 구독 인증기관 무료, 개인회원 유료
Injection rate, injection quantity and injection timing of fuel are controlled precisely by electric control in CRDI system.Particularly, injection rate being influenced with injection pressure affects to spray characteristics and fuel-air ratio, so it is a very important factor in diesel combustion. In this study, injection rates in accordance with injection pressure at a constant ambient pressure were measured with Zeuch's method. Under the same condition, non-evaporating spray images were taken with a high speed camera and analyzed carefully with Adobe Photoshop CS3. Macroscopic spray characteristics and breakup processes in the spray could be found from the examined and analyzed data. Injection start time and injection period were practically affected with injection pressure. Also, initial injection rate, spray penetration, spray angle and breakup of high density droplets region in the spray were affected with injection pressure. The results and techniques of spray visualization and injection rate measurement in this study would be practically effective to study a high pressure diesel spray for common rail direct injection system.
4,000원
10.
2016.02 구독 인증기관 무료, 개인회원 유료
We examined monthly changes in the rate of fishes by-caught by gape net with wings and their immature ratio in thecoast of Yeosu and Jindo Island, Korea. A minus correlation between bycatch rate, the ratio of fishes except for anchovy, Engraulis japonicus, to all fishes collected by gape net with wings, and individuals of the collected anchovy was significantly observed, implying that as the anchovy catch decreased and the bycatch rate increased. Immature ratios by the dominant bycatch species during the study is the following; Leiognathus nuchalis was 72.7~99.0%, Sphyraena pinguis was 84.0%, Sardinella zunasi was 90.0%, others (Leptocephalus, Trichiurus lepturus, Ammodytes personatus, Sphyraena pinguis, Trachurus japonicas, Mugil cephalus and Erisphex pottii) were 100.0%. In order to decrease the high bycatch rates of immature fishes in spring and autumn, our study suggested increasing of codend mesh size and developing suitable bycatch reduction devices in a gape net with wings.
4,000원