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
53권 4호 (2017년 11월) 18건
1.
2017.11
구독 인증기관 무료, 개인회원 유료
In this paper, numerical modeling is conducted to analyze the tension of an anchor line by varying the size and drag coefficient of a buoy when the trapnet is influenced by the wave and the current simultaneously. A mass-spring model was used to analyze the behavior of trapnet underwater under the influence of waves and current. In the simulation of numerical model, wave height of 3, 4, 5 and 6 m, a period of 4.4 s, and the flow speed of 0.7 m/s were used for the wave and current condition. The drag coefficients of buoy were 0.8, 0.4 and 0.2, respectively. The size of buoy was 100, 50 and 25% based on the cylindrical buoy (0.0311 ㎥) used for swimming crab trap. The drag coefficient of the trapnet, the main model for numerical analysis, was obtained by a circular water channel experiment using a 6-component load cell. As a result of the simulation, the tension of the anchor line decreased proportional to buoy’s drag coefficient and size; the higher the wave height, the greater the decrease rate of the tension. When the buoy drag coefficient and size decreased to one fourth, the tension of the anchor line decreased to a half and the tension of the anchor line was lower than the holding power of the anchor even at 6 m of wave height. Therefore, reducing the buoy drag coefficient and size appropriately reduces the trapnet load from the wave, which also reduces the possibility of trapnet loss.
4,000원
2.
2017.11
구독 인증기관 무료, 개인회원 유료
Comparative fishing experiments were conducted in the eastern coastal waters near Uljin, Korea from 2002 to 2004, using the experimental trammel nets to estimate the selectivity for spinyhead sculpin Dasycottus setiger. The inner panels of the nets were made of nylon monofilament with four mesh sizes (82.2, 89.4, 104.8, and 120.2 mm) while its two outer panels were made of twisted nylon multifilament with a mesh size of 510 mm. The SELECT (Share Each Length’s Catch Total) procedure with maximum likelihood method was applied to obtain a master selection curve. The different functional models (normal, lognormal, bi-normal, and logistic model) were fitted to the catch data. The lognormal model with the fixed relative fishing intensity was chosen as the best-fitted selection curve through comparison of model deviance and AIC (Akaike’s Information Criterion). The optimum relative length (the ratio of fish total length to mesh size) with the maximum relative efficiency was obtained as 2.492.
4,000원
3.
2017.11
구독 인증기관 무료, 개인회원 유료
Fishing dredge in Jeollabuk-do began to become widespread in the 1960s and has continued to catch diverse kinds of shellfish in the productive fishing grounds around Dongjin River, Mangyeong River and Geum River estuaries. Since the 1970s, the construction of various large-scale industrial complex and the implementation of Saemangeum reclamation project have resulted in a decrease in main fishing areas and a sharp decline in shellfish production. As a result, dredge fishery has faced many difficulties. Dredge fishery in Jeollabuk-do is carried out with a total of 30 fishing permits as of 2016. Surf clams, hen clams, bladder moon snails, and common orient clams were mainly caught before the construction of Saemangeum dike while comb pen shells, purple whelks and ark shells are mainly caught afterwards. Inside the Saemangeum dike, most fish species have disappeared due to low water level and low salinity, and littleneck clams are caught using a jet pump type of fishing dredge. Outside the dike, the diversity of shellfish species has been reduced; comb pen shells are mainly caught. In this process, a lot of friction occurs due to the use of a reformatted dredge. Therefore, a lot of research needs to be conducted in the near future.
4,000원
4.
2017.11
구독 인증기관 무료, 개인회원 유료
The tension of warp from trawler and sea-floor contact can generate tilt and wake turbulence around otter boards. Preliminary measurements of otter board tilt and 3-D flow velocity during bottom trawl operations were taken using a vector instrument to investigate the effects of wake turbulence at the trailing edge of the otter board. Tilt data (i.e., yaw, pitch, and roll) at 1 Hz and flow data (velocities in the towing, lateral, and vertical directions) at 16 Hz were analyzed to determine their periods and amplitudes using global wavelet and peak event analyses. The mean period (±standard deviation) of the tilt from the peak event analysis (5±2 s) was longer or double than that of flow velocity (3±2 s). The two periods also had a significant linear relationship. The turbulence rate of flow was 30-50% at the trailing edge and was closely related to roll deviation. The frequency of phase difference ratios (i.e., peak time differences between tilts and flow periods) was significantly different from random occurrence in two trials, possibly due to side tidal effects. However, in the other trials, flow peaks were random, as shown by the even peak times between tilts and flows. Future studies should focus on reducing tilt variation, wake turbulence, and bottom contact to stabilize otter board motion.
4,300원
5.
2017.11
구독 인증기관 무료, 개인회원 유료
The catch composition of commercially important species of the stationary lift net at Barangay Gines, Miagao, Iloilo, the Philippines was investigated from December 2013 to May 2014 during the different phases of the moon. A total of 486 kg of fish coming from 12 different genera, including mollusk and crustaceans, was caught and identified from the catch of the stationary lift net. Among the 12 genera identified from the catch of stationary lift net, anchovy (Stolephorus), sardines (Sardinella), squid (Loligo) and mysid shrimp (Acetes) were considered to be commercially important due to their value. Acetes catch was highest during the new moon in the month of January. Loligo catch was also high during the new moon except in the month of May. Stolephorus catch was also highest during the new moon except in the month of January. Sardinella catch was highest during the first quarter in the month of February. Full moon had the lowest catch all throughout the duration of the study while new moon had the highest catch during December 2013 to March 2014 and first quarter was the highest in the months of April and May.
4,000원
6.
2017.11
구독 인증기관 무료, 개인회원 유료
The purpose of this study is to analyze the efficiency of distant-water longline fishing vessels in the Pacific Ocean and the gap in efficiencies among individual vessels. In order to estimate the efficiency, the dependent variable is set as an amount of catch and independent variables include number of crew, number of hooks, number of vessel size, and vessels engine power associated with fishing activities of distant water longline fisheries. Analytical result was shown as follows: first, the average efficiency of distant-water longline fishing vessels in the Pacific Ocean was found to be 94%. Second, the number of hooks were found to be statistically significant in each input variable and the appropriate control of the number of hooks would be expected to have a positive effect on the efficiency. Third, the relationship between the age of a vessel and the efficiency was not found statistically.
4,000원
7.
2017.11
구독 인증기관 무료, 개인회원 유료
The age and growth of pointhead flounder, Hippoglossoides pinetorum caught by gill nets was analyzed in this study from March 2015 to July 2017. New annuli were formed in H. pinetorum otoliths annually, and the boundary was set between the opaque and translucent zones from March and April. The relationships between total length (TL) and body weight (BW) were BW = 0.0025 TL3.409 (r2 = 0.9551) for females and BW = 0.0057 TL3.138 (r2 = 0.9163) for males. In this study, the ring of pointhead flounder, H. pinetorum was formed between 3 and 8 for females and between 3 and 6 for males. Total length (TL) and otolith radius (OR) were measured as follows: TL = 7.142 OR + 0.769 (r2 = 0.793) for females and TL = 6.498 OR + 1.706 (r2 = 0.652) for males. The mean distances of first ring (r1) were 0.92 mm and 0.91 mm for females and males respectively. The TLs at the time of annulus formation, back-calculated from the otolith-length relationship by reference to the von Bertalanffy growth curves, were Lt = 43.59 (1-e-0.15(t+0.007)) for females and Lt = 28.13 (1-e-0.26(t+0.006)) for males while the growth between female and male was different.
4,500원
8.
2017.11
구독 인증기관 무료, 개인회원 유료
This study was conducted to understand the relationships between fish and zooplankton of distribution in the coastal waters of the East Sea from May to August 2016 using hydroacoustic. To distinguish between fish and zooplankton, we used the time varied threshold (TVT) method at the frequency of 120 kHz. As a result, the mean nautical area scattering coefficient (NASC) of fish was highest at 913 m2/n.mile2 in June and lowest at 315 m2/n.mile2 in July. The mean NASC of zooplankton was highest at 247 m2/n.mile2 in May and lowest at 70 m2/n.mile2 in July. The mean NASC of fish and zooplankton showed a significant difference (P < 0.05) with high correlation (R2 = 0.84). In addition, there was no significant difference in the mean NASC of fishes and zooplankton by depth (t-test, person correction = -0.17, p > 0.05).
4,000원
9.
2017.11
구독 인증기관 무료, 개인회원 유료
For scientific research, a number of acoustic surveys using commercial echosounders equipped in fishing vessels were conducted throughout the world; however, few studies were performed in South Korea. Hence, this research is an preliminary study for presenting the application of a sounder from a fishing vessel. The fishing operations using a pair trawler (7 Cheonghae) was conducted in the Northwest-Western sea of Jeju Island from 20 to 23 April, 2016. Substantial impulse noises and attenuated signals were eliminated by the latest algorithms. Acoustic signals were grouped into the fish aggregations and long layer-like signals. The fish aggregations appeared between 30 and 60 m, and long layer-like signals showed the diurnal vertical migration. Energetic, morphological and positional properties of the fish aggregations and layer-like signals were described. The fish aggregations appeared mainly between sunrise and sunset; however layer-like signals tended to be presented regardless of time in consideration of the time series analysis. On the basis of the consignment sales, Scomberomorus niphonius, the target species of F/V 7 Cheonghae, was the highest catch with 4,280 kg (74.6%) and might have appeared in fish aggregations and layer forms.
4,000원
10.
2017.11
구독 인증기관 무료, 개인회원 유료
We measured the target strength according to the swimming tilt angle and size change for Pacific herring at the frequency of 70 kHz as the basic database in order to estimate its abundance as well as density in the survey area using the hydroacoustical method. The number of the sample used in this study was 14 individuals, and its size distribution by fork length ranged between 20.3 and 29.8 cm and wet weight was measured between 187.6 and 269.9 g. The variation of TS according to the swimming angle (-30~30°) was measured between 10.3 and 18.8 dB in frequency range, the highest value was measured at head-down of Pacific herring in the tilt angle range between 5 and 9 deg. of its swimbladder. The relationship between TS–FL of herring was the same as TS = 20log10 (FL) – 66.79 when its swimming tilt angle in the daytime (3.8 ± 6.0°) and nighttime (-3.2 ± 13.6°), respectively.
4,000원
11.
2017.11
구독 인증기관 무료, 개인회원 유료
A centrifugal cyclone dust collecting apparatus includes a hydro cyclone dust collecting apparatus for separating solid or liquid using liquid or suspension as a medium. In this study, the formation mechanism and improvement of air core and inner air layer were confirmed through Particle Image Velocimetry. These results showed that the modified experimental model was designed in the conventional method suitable for the separation of juvenile fish and eggs. The inlet speed of the multi-stage hydrocyclone dust collector, which can increase the inlet velocity and minimize floatage in the turbulence chamber, was increased from 0.15 to 0.30 m/s. As a result, the air core was stably formed, the inner air layer was increased with increasing speed. In addition, the dust collecting efficiency of egg and juvenile fish was 97.8% on average, It can infer that this system confirmed the ability to efficiently collect particles of 40 μm or more.
4,000원
12.
2017.11
구독 인증기관 무료, 개인회원 유료
The objective of this study was to prove possible effects of a habitable place for fish around semi-submersible drilling rig which measured underwater radiated noise, irradiance distribution of rig's light and conducted experimental fishing in Malaysia territory and observed for distribution of fishes around the rig by ROV during drilling operation in the East Sea of Korea. As a result underwater radiated noise was 130 dB/μPa from 156.25 to 187.50 Hz, irradiance distribution of light was between 21.5 and 43.1 lx. Despite this result, underwater radiated noise was not a threat to fish around rig and low irradiance distribution of light also played a role in the luring influence of the fishes at night. Fish showed up in the beginning of drilling operation and at the end of drilling operation. However, there are few fish in the midst of drilling operation. The main reason for this result was the destruction of the habitable place due to blow out mud and broken pieces of ground formation in drilling hole. The results are expected to contribute to reasonable fishery management around rig.
4,000원
13.
2017.11
구독 인증기관 무료, 개인회원 유료
As invigoration plan of the marine tourism, Busan City has the plan to operate the cruise ship inside of the harbor, but the area has narrow water way with heavy traffic. As a result it is requested to evaluate the safety for the preparation of actual navigation. In this study, the Ship Handling Simulation (SHS) Assessment was conducted, which is regulated by the Maritime Traffic Safety Audit Scheme (MTSAS) in compliance with the Marine Safety Law and the Maritime Traffic Risk Assessment System based on the Electronic Chart Display and Information System (ECDIS). The proximity assessment, control assessment and subjective assessment were implemented, which is enacted by the Marine Safety Law by using the SHS. In the case of proximity assessment, the probability of trespass was not analyzed. As the control assessment, the swept path was measured at 11.7 m and 11.5 m for port entry and port departure respectively, which exceeded the width of the model vessel, 10.4 m over; it was considered as a marginal factor. As a result of the subjective evaluation of the navigator, there would be no difficulty on ship maneuvering by paying particular attention to the mooring vessel nearby the Busan Bridge and Yeongdo Bridge as well as the coming vessel from the invisible sea area when the vessel is entering and departing the port. The Marine Traffic Risk Assessment System analyzed as [Cautious] level until the vessel passed the Busan bridge and the curved area at 5 kts and it became to [Dangerous] level from where it left 75 m to the Busan Bridge. When the vessel passed the Busan Bridge and the curved area at 10 kts and entered the narrow area, it indicated the [Dangerous] level and became to [Very dangerous] level from where it left 410 m to the Busan bridge. In conclusion, the vessel should maintain at the speed of 5 kts to reduce the risk when it passes this area.
4,000원
14.
2017.11
구독 인증기관 무료, 개인회원 유료
The most frequent occurring and the serious marine casualties in fishing vessels are the collision in statistics from Korea Maritime Safety Tribunal (2008-2015). Collisions are is given a great deal of weight in all marine casualties, and the main cause of collisions is the negligence of watching. From this point of view, this study deals with the collision and its immediate cause, the negligence of watching which are main factors on the indirect causes. Basic analyzing data was gathered from the questionnaire made by experts of sea service part, and analyzed by using the fault tree analysis (FTA). From the result of the study, the occurrent probability of the negligence of watching in the collision due to the indirect causes occupied 64.9%, and its probability caused by the man factors was less than the other factors; i.e. the media factors and the management factors. For the reduction of the negligence of watching in the collision from this study, it needs an effort to remove not only the man factors, but also the media factors and management factors.
4,000원
15.
2017.11
구독 인증기관 무료, 개인회원 유료
Distribution and composition of the seabed litters in the exclusive economic zone of the West Sea of South Korea including 18 sea-blocks were investigated using a bottom trawl gear of the R/V Tamgtu 20 (National Institute of Fisheries Science) from 24th April 2011 to 4th May 2012. Each trawl shot was conducted for an hour in each sea-block and the total trawl shots was 18. As a result, 325.6 kg of seabed litter in total has been collected. The quantity of the seabed litter was highest at No. 202 of the sea-block, close to the Heuksan-Do. The highest occupied sea material was plastic (83.1% of entire seabed litters), the second highest material was metal combined with plastic (10.6%), and glass (2.9%), metals (2.3%), vinyl (0.6%), cloth (0.4%) and wood (0.2%) in order. The origin of seabed litters was from fishing gear (89.0% of all seabed litters). Therefore, it could be assumed that most seabed litters were derived from the fishing activity for example fishing nets and ropes.
4,000원
16.
2017.11
구독 인증기관 무료, 개인회원 유료
The improvement of resistance performance for the 4.99 ton class fishing boats was shown. The 4.99 ton fishing boats are the most commonly used one in the Korean coastal region. The evaluation of resistance performance was estimated by the Computational Fluid Dynamics (CFD) analysis. The CFD simulation was performed by the validation for various types of bow shapes on the hull. The optimized hull form from the simulation was selected and showed the best resistance performance. This hull type was tested on the towing tank in the National Institute of Fisheries Science (NIFS). The effective horsepower (EHP) was estimated by the resistance test on the towing tank with the bare hull condition. The drag force on the three service speed conditions was obtained for the resistance analysis to power prediction. The measured drag forces are compared with the results from the CFD simulation with one another. As results of the model tests, it was confirmed that the shape of the bow is an important factor in the resistance performance. The effective horsepower decreased about 30% in comparison with the conventional hull form. Also, the resistance performance improved the reduction of required horsepower, which especially contributed to the energy-saving for the fisheries industry. In the CFD analysis, the resistance performance improved slightly. In this case, the ratio of the residual resistance (CR) in the total resistance (CT) was high. Therefore, the CFD analysis was not enough to satisfy with reflection for the free surface and wave form in the CFD procedure. Both model test and CFD calculation in this study can be applied to the initial design process for the coastal fishing vessel.
4,000원
17.
2017.11
구독 인증기관 무료, 개인회원 유료
We propose some countermeasures needed to cope with fortifying international regulations for fisheries subsidies. The government should rigorously select the recipients of fisheries subsidies to ensure that they are not engaged in ineffective projects by resorting to subsidies. On the other hand, the government should make the individual applicant’s application for the subsidies easier by exempting them from the submission of a burdensome feasibility report. As for the strengthening regulatory international movements against the fisheries subsidies, we can consider the following countermeasures. One is not to designate and provide prohibitive subsidies in such a way that violates international norms. The other one is to reform the domestic fisheries subsidies system in Korea with the following points considered. It should be considered that fisheries subsidies, which can be categorized as the actionable subsidies, should not be granted to the items that can be exported but to the items that can be used for domestic consumption or processing. In the case of non-actionable subsidies, the subsidies are mainly allowed for promotion of public-sector research and development, regional development, and adaptation to new environmental regulations. Thus, the non-actionable subsidies should be designated in the consideration of the allowances for these activities.
4,800원
18.
2017.11
구독 인증기관 무료, 개인회원 유료
This study aims to suggest the methodology to improve to estimate back-calculated fish growth parameters using weighted average. It is to contribute to correct errors in the calculation of back-calculated growth equation with unequal numbers of sample by age. If the numbers of sample were evenly collected by age, each back-calculated length at age was equal between arithmetic and weighted averages. However, most samples cannot be evenly collected by age in reality because of different catchability by fishing gear and limitation of environment condition. Therefore, the estimation of back-calculated length by weighted average method is essential to calculate growth parameters. There were some published growth equations from back-calculated length using a simple arithmetic average with different numbers of samples by age when searching for back-calculated growth equations from 91 relevant papers. In this study, the process of deriving growth equation was investigated and two different average calculations were applied to a fish growth equation, for example of Acheilognathus signifer. Growth parameters, such as L∞, k and t0, were estimated from two different back-calculated averages and the growth equations were compared with growth performance index. Based on the correction of back-calculated length using weighted average by age, the changes by female and male were -14.19% and -5.23% for L∞, and 59.28% and 18.91% for k, respectively. The corrected growth performance index by weighted average improved at 7.05% and 2.46% by female and male, respectively, compared to the arithmetic averages.
4,000원
