• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.13 no.1
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• pp.17-25
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• 1977

For four calender years (1971-1974), daily observations of weather conditions (air temperature, humidity, wind speed, wind direction, cloud amount, fog, precipitation etc.) at six stations in the north western Pacific Ocean are used to calculate mean monthly values and to check extra-conditions. At Petropavlosk and Miko'skoe, where indicate the characteristics of modified continental climate, the temperature and humidity are high in summer, and Iow in winter. At A Dak and She Mya, where indicate the characteristics of warm current type maritime climate, humidity is high in all season and annual range of air temperature is nearly negligible. At Simusir and Vasi!' eva, where indicate the characteristics of cold current type maritime climate, humidity is high in all season and annual range of air temperature is $15^{\circ}C.$ As dry cooling power is relatively high in winter, working condition on deck is bad. Most of fogs are advection fog in the area of cold current type climate in summer.

• The Journal of Fisheries Business Administration
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• v.40 no.1
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• pp.153-172
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• 2009

Developing foreign fishing ground executed in various uncertainty such as fishing price, oil price, exchange rate. But traditional economic evaluation method, CVP(Cost-Volume-Profit) analysis doesn't consider uncertainty of foreign fishing ground. So we need new approach about economic evaluation that can take into account uncertainty. This study focus on the economic evaluation about experimental survey of tuna fishing grounds in the north pacific ocean by sensitive analysis and simulation. The results of the economic evaluation can be summarized as follows. First, when we take it for granted that the other uncertainty factors except for each fishing price, oil price, and exchange rate are constant. CVP gross sales has positive relation to the increasing rate of oil price, exchange rate(W/$) and negative relation to the increasing rate of fishing price and exchange rate(W/${\yen}$). Second, when we are supposing that fishing price, oil price, and exchange rate are followed. the probability of less than CVP gross sales is A ship(48.87%), B ship(49.64%), C ship(50.55%). Consequently, the economic evaluation by sensitive analysis and simulation is more useful tool than CVP(Cost-Volume-Profit) analysis under uncertainty.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.5
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• pp.1380-1394
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• 2015

This paper deals with the geographical scope of the East Sea introduced by major domestic institutions. The East Sea surrounded by South Korea, North Korea, Russia, Japan has a variety of marine resources, and is the very appropriate natural laboratory to study future global changes as a miniature ocean. However, there is a continuous conflict between Korea and Japan over the name of the East Sea because of the nature of international waters. So we need the active research achievements based on the exact geographic knowledge of the East Sea to promote the legitimacy of the East Sea in the international community. Nevertheless each domestic institution has a different way to define the southern border of the East Sea so that it showed a difference about linear distance of up to about 44 km. Also, they have defined the scope of East Sea not as the entire East Sea surrounded by South Korea, North Korea, Russia and Japan but as the jurisdiction of the Republic of Korea. It caused serious confusion about accurate statistical knowledge about East Sea such as area, volume, and mean water depth. Therefore, clear social consensus about the geographical scope of the East Sea would be required, there is also the need to institutionalize a legal order to spread it.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.35 no.3
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• pp.227-236
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• 1999

Temperal and spacial analysis for catches have been drawing up a catch distribution chart and analysing catches and CPUE(Catch Per Unit Effort) using catch data with purpose of obtaining basic data to establish a selective method of effective fishing the tuna purse seine fishing ground.The temperature profile section and catch was surveyed to analyse the effect of catch in relation to the fishing ground environment.The results are as follows ;1. As for the catch variation between 1983 and 1984, the catch mainly took place on150^{\circ}E$, and after that it moved eastward enlarging the range of catch. In the monthly catch variation between January and February, the catches mainly happened on 135$^{\circ}$~ 150$^{\circ}$E, and then moved to the gradually westward. However, from July it moved to the South and from October Southeast.2. As to the eatch ratio for the school associated with the drifted object, the pelagic migrating school and the school associated with the biological objects, the catch ratio for the school associated with the drift objects was the highest. The catch ratio for the school associated with the drifted object was high in June, July and November whiles between January and March for the pelagic migrating school.3. SST(Sea Surface Temperature) was around 28~29^C$ on the observing line of 137^{\circ}E$ and the catches took place in the north equatorial counter-current situated on around $5^{\circ}~6^{\circ}N$. SST in the northern summer was 1^C$higher than winter and it was about 29~30^C$. The catch happened with the center of north equatorial counter-current. The reason why the catch mainly took place on the north equatorial counter-current is that main catch of tuna purse seine was the school associated with drift objects. It is thought that the fishing grounds are made in waters that have many drift objects like drift logs from the coast.

• Journal of the Korean Association of Geographic Information Studies
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• v.16 no.4
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• pp.120-140
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• 2013

We investigated the occurrence of red tide, harmful algal blooms(HABs), at the end of 14th century until the beginning of 19th century recorded in the Annals of the Joseon Dynasty, which are the authentic and encyclopedic annual records of the Joseon Dynasty of Korea. In total, 81 cases of HABs are recorded in the annals for which authors draw a table and maps. The number of HABs occurrence at each sea is as follows: 68 times at the South Sea; 50 times at the East Sea; and 23 times at the Yellow Sea. A region hit by red tide most frequently was Gyeongsang-do Province (over 80 times), which borders on both the South Sea and the East Sea. HABs written in the annals follow two distinctive occurrence patterns. The first pattern shows red tide started at Gangwon-do Province in March, spread north to Hamgyeongnam-do Province in April, and moved further north to Hamgyeongbuk-do Province in May and June. On the other hand, the second pattern shows red tide occurred in Gyeongsangnam-do Province in August and then expanded north to Gyeongsangbuk-do Province in September. HABs generally happened from March to September, culminating in August. Paralytic shellfish poisoning incidents involving human deaths were reported in Jinhae, Geoje and Tongyeong, occurring February to June. Fish mortality increased throughout Gyeongsang-do Province from July to September. HABs occurred on an extensive scale from 1394 to 1451 and again from 1654 to 1706. HABs also occurred on a lesser scale from 1493 to 1534 and again from 1588 to 1609. In general, vast HABs occurred in odd years (1399, 1403, 1413 and 1681).

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.43 no.4
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• pp.310-319
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• 2007

To investigate the catches of squid jigging fishery, a series of fishing experiments was conducted in the high seas of the Northwest Pacific($40^{\circ}-43^{\circ}N$, $150^{\circ}-155^{\circ}E$) during the period of 1 August to 22 October 2005 by commercial fishing vessel. The number of 142 test fishing was carried out in the Northwest Pacific during 83days. The total catch were 47,524kg as 4 squid species and CPUE was $8.9kg/line{\cdot}day$. CPUE showed high values in the frontal zone during the survey. Main squid species caught from the experimental fishing were the neon flying squid, Ommastrephes bartrami(96.8%) and the boreopacific gonate squid, Gonatopsis borealis(3.2%). Dorsal mantle length of the neon flying squid were increased by the time and increasing of the hook size. Loss rate of the neon flying squid in the water showed the highest values in 28.2% compare to the others. And the loss rate of the front roller and in the air were 1.1% and 1.0%, respectively.

• Fisheries and Aquatic Sciences
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• v.22 no.8
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• pp.18.1-18.5
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• 2019

The development of sex-specific genetic assays in a species provides both a method for identifying the system of sex determination and a valuable tool to address questions of conservation and management importance. In this study, we focused on the identification of single nucleotide polymorphisms (SNPs) that differentiate genetic sex in burbot Lota lota. Burbot are the only true freshwater representative of the cod family and a species of conservation and management importance throughout Eurasia and North America. To identify sex-specific SNPs, we utilized restriction site-associated DNA sequencing (RADseq) to interrogate thousands of SNPs in burbot samples of known phenotypic sex. We discovered 170,569 biallelic SNPs, none of which fit the pattern expected under female heterogamety. However, we identified 22 SNPs that fit the pattern expected under male heterogamety (males heterozygous XY, females fixed XX) and, from these, developed two genetic assays that robustly (~ 97% genotyping success) and accurately (> 99% correct) sexed burbot samples. These sex-specific genetic assays will benefit growing conservation aquaculture programs for this species and allow future assessments of sex-specific migration, growth, and mortality.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.6
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• pp.754-770
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• 1994

Suspended sediment distribution and water column processes in the upper Neuse River estuary, North Carolina, were monitored monthly from February 1988 through February 1989, in order to identify the turbidity maximum, to determine its temporal and spatial variation under changing conditions(freshwater runoff, wind, and tide). During most of the observation periods a weak turbidity maximum, associated with the estuarine circulation processes, developed at a flow convergence zone, near the upstream limit of salt intrusion. No turbidity maximum was found when the water column was vertically homogeneous with respect to salinity and when there was no consistent upstream bottom flow. Annual migration of the turbidity maximum, accompanied by migration of salt intrusion, was over 20 km of the upper estuary. Due to the coincidence of dominant wind direction(NE-SW) with the main orientation of the Pamlico-Neuse system, wind played the dominant role in dynamics of the turbidity maximum by influencing the degree of salinity stratification and the extent and strength of estuarine circulation. Tidal effects on the sediment dynamics were negligible.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.6
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• pp.567-579
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• 1993

The response of sea levels to a typhoon in the north Japanese coast in the Japan Sea is investigated by using hourly ses level data($1966{\sim}1986$) and a numerical shallow water model with high resolution($5'{\times}5'$). The observed sea level analysis shows (1) progressive waves exist between Simonoseki(SS) and Maizuru(MZ) with the mean phase speed of about 4 m/s during the passage of the typhoon, (2) the phase speed between Sasebo(SB) and HK(Hakata) is slower(about 1.7 m/s), and (3) the maximum sea level at HK is achieved about 0.5 day later than that of SS. In many aspects, the numerical model results correspond well to the above observed features. In the model the progressive waves are identified as a topographic wave with the phase speed of about 4 m/s. Before the typhoon passes through the Korea Strait/ the Tsushima Strait, the wave propagations along the Japanese coast are significantly influenced by the southwestward coastal jet induced by the wind stress parallel to the coast. The waves start to propagate northeastward along the coast when the coastal jet is weakened.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.5
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• pp.323-330
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• 2005

Monthly distributions of fishing boats at night in the East Sea are described, using defense meteorological satellite program (DMSP)/operational linescan system (OLS) images and common squid (Todarodes pacificus) catches data. We also estimated temperature in 50m, which is main catch depth of the squid, by MCSST (multi-channel sea surface temperature). We examined DMSP/OLS, MCSST and other observation data from 1993 to 2000. We assumed that squid were caught in areas where fishing boats were located. Fishing boats at night appeared only near the Korea/Tsushima Strait from January to March. Fishing boats moved to the northward from April to Jun, distribution of fishing boats in spring appeared greater than those in winter. In summer (July-September), center of fishing grounds was formed near the Uleung Island in the south east coast of Korea. The north-south distribution range of fishing boats in October appeared to be greater than that in other months. In particular, we estimated main season of squid catches based on distribution range reflecting the number of fishing boats of north-south and east-west directions from September to December. Relationship between satellite estimate SST and in situ SST showed high correlation (0.91). The correlation between the SST and 50m depth temperature, estimated based on the satellite SST, was relatively high in February, April and October.