• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.39 no.1
• /
• pp.56-62
• /
• 2003

To investigate the entrapping behavior of blue crab, rock shell and green ling, which are mainly caught with the other trap nets in the coastal area of Yellow Sea, by the using duration of trap nets through the water tank experiment. We select the three kinds of trap nets which have different using duration such as new, 6 months and 12 months used one, and observe the entrapping ratio into the trap nets, respectively. In the mean while, in order to obtain the basic data for the estimate of mesh selectivity of the other trap nets, the entrapping behavior into the trap nets for green ling which has high activity compared to blue crab and rock shell, are examined to the three kinds of mesh size (35mm, 50mm and 65mm). The results are as follows ; 1. The mean entrapping ratio of blue crab by the using duration of trap nets in high with 4.4 fishes (44.0%) in the 6 months used one, become lower with 2.9 fishes (28.0%) in the new one, and with 2.0 fishes (20.0%) in the 12 months used one. 2. The mean entrapping ratio of rock shell by the using duration of trap nets in high with 7.3 fishes (36.7%) in the new one, and become lower with 7.2 fishes (35.8%) in the 6 months used one, and with 5.7 fishes (28.3%) in the 12 months used one. 3. The mean entrapping ratio of green ling by the using duration of trap nets in high with 3.4 fishes (34.0%) in the 6 months used one, and become lower with 3.0 fishes (30.0%) in the new one, and with 2.8 fishes (28.0%) in the 12 months used one. 4. The mean residual ratio of green ling by the mesh size of trap nets is high with 2.4 fishes (24.0%) in the 35mm mesh size, and become lower with 2.2 fishes (22.0%) in the 50mm mesh size and 2.0 fishes (20.0%) in the 65mm mesh size.

• Journal of Bio-Environment Control
• /
• v.18 no.2
• /
• pp.153-159
• /
• 2009

This study was carried out to investigate effect of $GA_{3}$ foliar application on the growth and flowering of Limonium spp. 'Ocean Blue' to develop an effective $GA_{3}$ treatment method for a year round commercial production. Plants were treated with different concentrations of $GA_{3}$ 0, 100, 200, 400, and 800 mg.$L^{-1}$ in summer, and 0, 100,200, and 400 mg.$L^{-1}$ in winter at seven weeks after transplanting. The effects of $GA_{3}$ treatment time (0, 10, 20, 30, 40, and 50 days after planting) and plant age (raising during 3, 5, 7, and 9 weeks) was investigated. The $GA_{3}$ treatment advanced bolting and flowering with little difference between the two seasons. In a summer culture the effective concentration of $GA_{3}$ ranged from 200 to 400 mg. $L^{-1}$, while in winter it was found to be 400 mg. $L^{-1}$. The $GA_{3}$ treatment at 10 days after planting significantly reduced days to flowering. However, the greatest cut flower yield was observed in plants treated at 20 days after planting. The $GA_{3}$ treatment to different age plants did not show a significant effect, except in the oldest (nine weeks old plants). In conclusion, to induce early flowering in Limonium spp. 'Ocean Blue', the proper concentration and time of application of $GA_{3}$ was 400 mg.$L^{-1}$ $GA_{3}$ treated to nine weeks old plants at 20 days after transplanting.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.44 no.4
• /
• pp.294-303
• /
• 2008

Squid jigging fishery is very important in that there are about 1,000 jigging vessels more than 10 tonnage and about 5,000 ones less than 10 tonnage in Korea. But the cost of oil which is used to light fishing lamps, goes significantly up to almost one hundred million won for 50 tonnage vessels and forty million won in case of vessels less than 10 tonnage. This cost has almost taken 40% of total fishing costs. That is, the fishing business condition of squid jigging fishery is recently in the very difficult situation. As oil price increases, the business condition of the fishery gets worse and worse. Therefore it is very urgent to develop an economical fishing lamp, to solve this problem of fishery's business difficulty. This research aims at developing a fishing lamp for squid jigging fishery using the light emitting diode which has very excellent efficiency and durability. We made a water tank with 20 meters width which is a shape of raceway to research behavioral characteristics of Japanese flying squid to LED light, and made an experiment to investigate optimum wave of LED light to lure squid. The method is to establish LED lamps on both ends of water tank and to observe squid's behavior. Colors and wave lengths of LED lamps, used in experiment, are red(634nm), yellow(596nm), green(523nm), blue(454nm) and white(454nm+560nm). In experiment for attractive capability of LED lamp to squids, Japanese flying squid are highly attracted to blue lamp and white lamp. However, they are dispersed to red and yellow lamps. In addition, Japanese flying squid have moved and stayed in both dark ends of water tank. When compared intermittent lamp with continuous lamp, Japanese flying squid are highly attracted to intermittent lamp when intermittent interval is 0.25 second.

• Spatial Information Research
• /
• v.23 no.3
• /
• pp.101-111
• /
• 2015

The Emirate of Abu Dhabi is swiftly rising into a newly industrialized country by achieving economic prosperity among the Islamic cultural regions of Middle East and North Africa(MENA). Abu Dhabi Emirate is performing the conversion from oil economy to non-oil economy and the sustainable urban development policy. However, there are various social and environmental problems in Abu Dhabi. In order to solve the urban problems caused by the rapid economic growth and the changes in society and environment, Abu Dhabi is recognizing the importance of spatial information and triggering the establishment of spatial information. Spatial information is regarded as a basic infrastructure for urban construction and enlarged as a blue ocean market in Abu Dhabi. However, the base of spatial data infrastructure in Abu Dhabi is not well managed in comparison to that of Korea. Especially, Abu Dhabi has some characteristics that it depends on foreign multinational companies and it does not have its own systemic organization and law system. To advance into Abu Dhabi spatial data market under-controlled by global vendors, it is necessary to identify the advantage and disadvantage on spatial data infrastructure of Abu Dhabi and required to establish the advance methods into niche markets by considering priority order of spatial information. Thus, this study aims to analyze the gap of spatial information between Abu Dhabi and Korea and suggest the short and long term development methods for spatial data infrastructure of Abu Dhabi. The results of gap analyses will be the milestone for Korean companies' advance into MENA.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.47 no.2
• /
• pp.79-87
• /
• 2011

A fishing lamp is fishing gear to gather fish in the night. But the cost of oil which is used to a light fishing lamp, goes significantly up to almost one hundred million won for 50 tonnage vessels and forty million won in case of vessels less than 10 tonnages. This cost has almost taken 30.40% of total fishing costs. As oil price increases, the business condition of the fishery gets worse and worse. Therefore, it is very urgent to develop an economical fishing lamp, to solve the problem of fishery's business difficulty. This research aims at developing a fishing lamp for squid jigging fishery and hairtail angling fishery using the LED, which has excellent efficiency and durability. One fishing lamp has about 160Watt capacity and five fishing lamps are installed one aluminium panel in which sea water flows to emit generated heat from LED to outside. Developed fishing lamp lights to an effective direction of jigging and angling operation. This fishing lamp can be controlled to light the direction of fish shoal because the aluminium panel can be controlled to up and down direction. The wave length of fishing lamp has white and blue color. White color light is to gather fish shoal of horizontal direction and blue color light is to gather fish shoal of vertical direction. After development of this fishing lamp, 60.110 units are established on the boat, and operated fishing. Consequently, in the case of squid jigging, spent energy was reduced to 39%, in the case of hairtail angling, 68% of spent energy was reduced. And the catch was more than another boat.

• Journal of Digital Convergence
• /
• v.20 no.2
• /
• pp.185-190
• /
• 2022

The purpose of this study is to suggest library marketing strategies for Korean academic libraries to provide sustainable services at COVID-19 pandemic situation. For this purpose, development plans of academic libraries in Korea were collected and homepages of academic libraries in and out of Korea were analyzed. This study found that academic libraries in and out of Korea had taken various measures to meet disastrous situation and had kept up services for users to make use of collection, facilities, services and programs of libraries without being disconnected. As a conclusion, this study suggests reinforcement of basics and value marketing, space marketing, blue ocean marketing as library marketing strategies for providing sustainable services. This study can be used as a reference for academic libraries and librarians to sustain or extend library services. The marketing strategies suggested in this paper can be helpful for academic libraries to overcome pandemic crisis in Korea. As follow-up studies, an in-depth case study about academic libraries which develop and activate new services and programs in and out of Korea to face COVID-19, a study on developing in-depth strategies of various library marketing to stabilize library services are needed.

• Korean Journal of Remote Sensing
• /
• v.39 no.6_2
• /
• pp.1565-1576
• /
• 2023

An atmospheric correction algorithm based on the radiative transfer model is required to obtain remote-sensing reflectance (R_rs) from the Geostationary Ocean Color Imager-II (GOCI-II) observed at the top-of-atmosphere. This R_rs derived from the atmospheric correction is utilized to estimate various marine environmental parameters such as chlorophyll-a concentration, total suspended materials concentration, and absorption of dissolved organic matter. Therefore, an atmospheric correction is a fundamental algorithm as it significantly impacts the reliability of all other color products. However, in clear waters, for example, atmospheric path radiance exceeds more than ten times higher than the water-leaving radiance in the blue wavelengths. This implies atmospheric correction is a highly error-sensitive process with a 1% error in estimating atmospheric radiance in the atmospheric correction process can cause more than 10% errors. Therefore, the quality assessment of R_rs after the atmospheric correction is essential for ensuring reliable ocean environment analysis using ocean color satellite data. In this study, a Quality Assurance (QA) algorithm based on in-situ R_rs data, which has been archived into a database using Sea-viewing Wide Field-of-view Sensor (SeaWiFS) Bio-optical Archive and Storage System (SeaBASS), was applied and modified to consider the different spectral characteristics of GOCI-II. This method is officially employed in the National Oceanic and Atmospheric Administration (NOAA)'s ocean color satellite data processing system. It provides quality analysis scores for R_rs ranging from 0 to 1 and classifies the water types into 23 categories. When the QA algorithm is applied to the initial phase of GOCI-II data with less calibration, it shows the highest frequency at a relatively low score of 0.625. However, when the algorithm is applied to the improved GOCI-II atmospheric correction results with updated calibrations, it shows the highest frequency at a higher score of 0.875 compared to the previous results. The water types analysis using the QA algorithm indicated that parts of the East Sea, South Sea, and the Northwest Pacific Ocean are primarily characterized as relatively clear case-I waters, while the coastal areas of the Yellow Sea and the East China Sea are mainly classified as highly turbid case-II waters. We expect that the QA algorithm will support GOCI-II users in terms of not only statistically identifying R_rs resulted with significant errors but also more reliable calibration with quality assured data. The algorithm will be included in the level-2 flag data provided with GOCI-II atmospheric correction.

• The Korean Journal of Malacology
• /
• v.24 no.3
• /
• pp.229-241
• /
• 2008

Changes of growth and histopathological feature in the mantle structure of the equilateral venus, Gomphina veneriformis exposed to tribultyltin chloride (TBTCl) for 36 weeks were observed. Concentrations of TBTCl were 0, 0.4, 0.6, and $0.8{\mu}g/L$. A regression analysis by power function of SPSS was shown that the growth of experimental groups was significantly decreased after 12 weeks of exposure. For histological analysis, mantle tissues were characterized using H-E stain, AB-PAS (pH 2.5) reaction and Masson's trichrome stain, and epidermal layer thickness and mucous cell distribution were analysed using the image analyser. The mantle had 4-folds (inner-inner, inner-outer, middle, and outer) and its epidermal layer consisted of simple epithlia. A periostracum was observed in the periostracal groove between middle and outer fold. Inner epidermal layer consisted of simple ciliated columnar epithelia, but the outer epidermal layer consisted of simple non-ciliated columnar epithelia. Alcian blue positive mucous cells showed blue color (7462c, 653c) in the inner fold, violet color (2583c) in the middle fold, and blue color (647c, 7455c) in inner epidermal layer (numbers in the parenthesis are codes of Pantone process coated color). Hemolymph sinus in the mantle was extended, and mucous cells in inner plica of the middle fold were stained as blue (7455c) and violet (2587c), after 12 weeks of TBTCI exposure. Cilia and striated border were disappeared, and number of mucous cells in the inner epidermal layer was reduced. Serious histopathological changes in middle and outer fold near the periostracum were observed after 36 weeks. Moreover, epidermal layer thickness and mucous cell distribution were showed decreasing tendency as exposure time to TBTCI was increased. Results of this study suggested that TBTCl induced growth disorder with histopathological changes.

• Clean Technology
• /
• v.23 no.2
• /
• pp.188-195
• /
• 2017

This research studied the adsorption of basic dye, Basic Blue 3 (BB3) by using coal-based granular activated carbon (C-GAC) from aqueous solution. All experiments were performed in batch processes, and adsorption parameters such as C-GAC dosage, contact time, initial dye concentration and temperature were evaluated. The removal efficiency of BB3 was increased with increasing the C-GAC dosage and 100% of initial concentration, $50mg\;L^{-1}$ was removed above 0.2 g of C-GAC. Also, the time to reach equilibrium depended on the initial dye concentration. According to the Langmuir model, the maximum uptakes of C-GAC were calculated to be 66.45, 84.97 and $87.19mg\;g^{-1}$ at 25, 35 and $45^{\circ}C$, respectively. In addition, thermodynamic parameters such as Gibbs free energy change, enthalpy change and entropy change were investigated.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.19 no.2
• /
• pp.137-143
• /
• 2016

The sedimentary environment and sediment were surveyed at the West-Northern site of Chagwi-do nearby Jeju Island for the design of the embedded suction anchor system of 10 MW-class floating wave-offshore wind hybrid power generation system. According to the classification scheme of Chough et al.[2002], the echo type of the seismic profiles using the chirp III was classified. As a results, the center and west-northern area of survey site were proved to be type I-3 where subbottom layer with thickness 5~15 m exists under the flat seafloor. On the other hands, the east-southern area were regarded to be type I-1, I-2 and III-1 where seafloor reflection is much stronger than type I-3. Also, the physical tests (unit weight, moisture content, grain size, liquid limit, specific gravity) were performed with samples taken from 8 fixed locations. It is found that the sand (SP), the sand blended with silt (SM) and the mixture of SP-SM are distributed uniformly on the survey area.