• Journal of Life Science
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• v.26 no.11
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• pp.1237-1244
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• 2016

A comprehensive analysis of the genetic diversity and relationship of the cold-water fishery walleye pollock (Theragra chalcogramma), the most abundant economically important fishery resource in the East sea of Korea, has not been carried out, despite its importance in Korea. The present study assessed the genetic diversity and relationship between five walleye pollock populations (Korean population, Russian population, USA population, and Japanese populations) of T. chalcogramma using eight microsatellite DNA (msDNA) markers to provide the scientific data for the preservation and management of the Pollock fishery resource. The results of the analysis of 186 individuals of the Pollock revealed a range of 7.13-10.63 numbers of alleles (mean number of alleles=9.05). The means of observed heterozygosity ($H_O$), expected heterozygosity ($H_E$) were 0.732 and 0.698, respectively. The results of genetic distance, Pairwise $F_{ST}$, UPGMA (UPGMA: un-weighted pair-group method with an arithmetical average) (the phylogenetic tree), PCA (PCA: Principal Coordinate analysis) analysis pointed to significant differences between the Korean population, Russian population, USA population, and Japanese populations, although small (p<0.05). These results shed light on the genetic diversity and relationships of T. chalcogramma and can be utilized for research on the evaluation and conservation of Korean T. chalcogramma as genetic resources.

• Journal of Bio-Environment Control
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• v.25 no.2
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• pp.89-94
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• 2016

This study was conducted to determine the optimum nutrient solution, pH, irrigation interval, light intensity and planting density to growth of common ice plant (Mesembryanthemum crystallinum L.) in a closed-type plant production system. Three-band radiation type fluorescent lamps with a 12-h photoperiod were used. Nutrient film technique systems with three layers were used for the plant growth system. Environmental conditions, such as air temperature, relative humidity and $CO_2$ concentration were controlled by an ON/OFF operation. Treatments were comparison of the nutrient solution of Horticultural Experiment Station in Japan (NHES) and the nutrient solution of Jeju National University (NJNU), pH 6.0 and 7.0, irrigation interval 5 min and 10 min, light intensity 90 and $180{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, and within-row spacing 10 cm, 15 cm, 20 cm and 25 cm with between-row spacing 15 cm. Optimum macronutrients were composed N 7.65, P 0.65, K 4.0, Ca 1.6 and Mg $1.0mM{\cdot}L^{-1}$. There were no significant interactions between pH 6.0 and 7.0 about shoot fresh weight and shoot dry weight of common ice plant. Irrigation interval 5 min and 10 min was also the same result. Shoot fresh weight and shoot dry weight were highest at $180{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Shoot fresh weight and shoot dry weight were decreased according to increasing the planting density. From the above results, we concluded that optimum nutrient solution, optimum levels of pH, irrigation interval, light intensity and planting density were 6.0-7.0 and 10 min, $180{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and $15{\times}15cm$, respectively for growth of common ice plant in a closed-type plant production system.

• Journal of Bio-Environment Control
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• v.25 no.2
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• pp.106-110
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• 2016

In this study, a planting density-growth-harvest (PGH) chart was developed to easily read the growth and harvest factors such as crop growth rate, relative growth rate, shoot fresh weight, shoot dry weight, harvesting time, marketable rate, and marketable yield of common ice plant (Mesembryanthemum crystallinum L.). The plants were grown in a nutrient film technique (NFT) system in a closed-type plant factory using fluorescent lamps with three-band radiation under a light intensity of $140{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and a photoperiod of 12 h. Growth and yield were analyzed under four planting densities ($15{\times}10cm$, $15{\times}15cm$, $15{\times}20cm$, and $15{\times}25cm$). Shoot fresh and dry weights per plant increased at a higher planting density until reached an upper limit and yield per area was also same tendency. Crop growth rate, relative growth rate and lost time were described using quadratic equation. A linear relationship between shoot dry weight and fresh weights was observed. PGH chart was constructed based on the growth data and making equations. For instance, with within row spacing (= 20 cm) and fresh weight per plant at harvest (= 100 g), we can estimate all the growth and harvest factors of common ice plant. The planting density, crop growth rate, relative growth rate, lost time, shoot dry weight per plant, harvesting time, and yield were $33plants/m^2$, $20g{\cdot}m^{-2}{\cdot}d^{-1}$, $0.27g{\cdot}g^{-1}{\cdot}d^{-1}$, 22 days, 2.5 g/plant, 26 days after transplanting, and $3.2kg{\cdot}m^{-2}$, respectively. With this chart, we could easily obtain the growth factors such as planting density, crop growth rate, relative growth rate, lost time and the harvest factors such as shoot fresh and dry weights, harvesting time, marketable rate, and marketable yield with at least two parameters, for instance, planting distance and one of harvest factors of plant. PGH charts will be useful tools to estimate the growth and yield of crops and to practical design of a closed-type plant production system.

• Journal of Bio-Environment Control
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• v.25 no.2
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• pp.83-88
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• 2016

In this study, previously reported surplus solar energy-related study result and current status of fan coil unit (FCU) for cooling and heating installed in the current sites were briefly examined and then a method to determine the number of FCUs required to recover surplus solar energy was schematically proposed to provide basic data for researchers and technical engineers in this field. The maximum, mean, and minimum outside temperatures during the experiment period were about $28.2^{\circ}C$, $4.4^{\circ}C$, and $-11.5^{\circ}C$, respectively. The horizontal surface solar radiation level outside the greenhouse was in a range of $0.8-20.5MJ{\cdot}m^{-2}$ and mean and total solar radiation were $10.8MJ{\cdot}m^{-2}$ and $1,187.5MJ{\cdot}m^{-2}$. The mean temperature and relative humidity in the greenhouse during the daytime were in a range of 18.8-45.5 and 53.5-77.5%. The total surplus solar energy recovered from the greenhouse during the experiment period was approximately 6,613.4MJ, which could supplement about 6.7% of the total heating energy 98,600.2 MJ. In addition, the number of FCUs installed for heating varies case to case, although similar FCUs are used. Thus, it is necessary to study the installation height, orientation and installation distance as well as the appropriate number of FCUs from the efficient and economical viewpoints. The required numbers of FCUs for surplus solar energy recovery were 8.4-10.9units and 6.1-8.0units based on air mass and circular flow rate that passed through the FCUs. Considering calculation methods and the risks such as efficiency and use environments of FCUs, it was found that about nine units (one unit per $24m^3$ approximately) needed to be installed. The required number of FCUs for surplus solar energy recovery was around one unit per $24m^3$ approximately.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.36 no.3
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• pp.175-185
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• 2000

This paper described on a basic study to organize fishing vessel control system in order to control efficiently fishing vessel in Korean offshore. It was digitalized ARPA image on the fishing processing of a fleet of purse seiner in conducting fishing operation at Cheju offshore in Korea as a digital camera and then simulated by used VTMS. Futhermore, it was investigated on the application of FVTMS which can control efficiently fishing vessels in fishing ground. The results obtained were as follows ; (1) It was taken 16 minutes and 35 minutes to casting and hauling net in fishing processing respectively. The length of rope pulled by scout boat was 200m, tactical diameter in casting net was 340.8m, turning speed was 6kts as well. (2) The processing of casting and hauling net was moved to SW, NE as results of simulation when the current direction and speed set into NE, 2kts and SW, 2kts respectively. Such as these results suggest that can predict to control the fishing vessel previously with information of fishing ground, fishery and ship's maneuvering, etc. (3) The control range of VTMS radar used in simulation was about 16 miles. Although converting from a radar of the control vessel to another one, it was continuously acquired for the vector and the target data. The optimum control position could be determined by measuring and analyzing to distance and direction between the control vessel and the fleet of fishing vessel. (4) The FVTMS(fishing vessel traffic management services) model was suggested that fishing vessels received fishing conditions and safety navigation information can operate safely and efficiently.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.31 no.4
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• pp.350-361
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• 1995

For the Purpose of the measurement of drifting condition of the anchovy drift gill net, some experiments were carried out in M. S Seong-Yang at the near sea of Kampo harbor in Korean east sea from August to October 1994, by using three set of GPS equipped with her net. The main results obtained are as follows : 1) In fixed position by GPS at Taebyon, the radius of 95% probability and shifted distance from standard position were respectively 79.8m, 21.0m. 2) The mean values of PDOP and HDOP of GPS at Taebyon were respectively 3.5, 1.9 and the stability of the position by GPS at Taebyon was found to be very high. 3) In the fishing ground of the position from Lat. $35^{\circ}$ 41.5'N to $Lat^{\circ}$. 43.5', from Long. $129^{\circ}$ 32.0'E to Long. $129^{\circ}$ 32.5'E, the direction of the whole stretched drift gill net was $190^{\circ}$ and the direction of the whole casted net was $200^{\circ}$ when casting the net was finished. When whole net was found to be drifting into the direction of $170^{\circ}\;to\;180^{\circ}$, and the mean drifting speed of that was 0.82kt. 4) In the fishing ground of the position from Lat. $35^{\circ}$ 44.0'N to Lat. $35^{\circ}$ 45.2'N, from Long. $129^{\circ}$ 30.1'E to Long. $129^{\circ}$ 31.2'E, the direction of the whole stretched net was 20$^{\circ}$ and the direction of the whole stretched net was $20^{\circ}$ when casting the net was finished. When hauling the net, the direction of the spreaded net appeared from the North into the South and the whole net was found to be drifting into the direction of $210^{\circ}\;to\;220^{\circ}$, and the mean drifting speed of that was 0.75kt. 5) In the fishing ground of the positioning from Lat. $35^{\circ}$ 44.9'N to Lat. $35^{\circ}$ 46.0'N, Long. $129^{\circ}$ 33.0'E to Long. $129^{\circ}$ 34.0'E, the direction to the whole stretched net was $35^{\circ}$ and the direction of the whole casted net was $50^{\circ}$ when casting the net was finished. When hauling the net, the direction of the spreaded net appeared into the South from the East and the whole net was found to be drifting into the direction of $330^{\circ}\;to\;40^{\circ}$, and the mean drifting speed of the was 0.63kt.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.33 no.2
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• pp.90-96
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• 1997

Until now the research was usually related in the fishing basket for crab charybdis japonica, concentrated one's effort to modification on the construction, shape, number of entrance of fishing basket etc.. But there's not make good used to the basically habit, shelter behavior of crab. etc., and was not fundamentally modified to the ability attracting the crab on net fishing basket. In this paper, first of all investigated to the behavior of crab in water tank and then two types modification fishing baskets could the increasing to ability attracting of crab on fishing basket were designed from the result obtained in this experiment and compared with modificated net fishing basket by Kim.Go(1987.1990) at a field and tank experiment. The results obtained are summarized as follows : 1. Being the fishing baskets had dropped in the tank bottom, the touched rate and reacted rate of crab according the elapsed time agree with to experiment of Kim.Go(1987.1990)in the mainly. however, in case of plate type tangle net, the touched rate of crab increased for a short time and then decreased and the reacted rate increased in a hurry to show a maximum and then was established. 2. The beginning catch time of crab was shortest in the plate type tangle net than the any fishing baskets because it's immediately entangled if the crab was touched only a part of body on net and latest in the net fishing basket. 3. A distance of between the touched rate and the reacted rate curve were the most short, wide in the plate type tangle net. therefore, the ability attracting of crab was excellent than the any fishing baskets and in case of pipe type fishing baskets, between the 150mm and 250mm seemed not difference and showed a tendency to increasing against the net fishing baskets. 4. Pipe type fishing baskets seemed to become a good shelting place for the crab because it showed a tendency to stagnate at the inside in that. 5. The mean catch per pot of crab among the net fishing basket, pipe type fishing baskets, plate type tangle net were highest in the pipe type fishing baskets than the net fishing basket and lowest plate type tangle net. Therefore it showed to difference against the tank experiment.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.24 no.2
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• pp.78-82
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• 1988

Near sea trawlers of Korea sometimes catch pelagic fishes like file fish by using midwater trawl gear even though usually catch bottom fish. It is reasonable to use the specific otter board as well as specific net in bottom trawling and in midwater trawling respectively. But, the trawlers are so small ranging 100 to 120GT, 700 to 100ps that it is very complicated to use different otter board for bottom trawling and for midwater trawling. The otter board for bottom trawling. is also used for the midwater trawling without any change even though the net is changed into the specific one. Although the otter board in the midwater trawling should be lighter than that for bottom trawling, to use otter board for bottom trawling directly for the midwater trawling without any change makes the net easily touch the sea bed and also make the horizontal opening of the otter boards be limited owing to the length of warp in the southern sea of Korea, main fishing ground of midwater trawling, which is 100m or so in depth. That is why the otter board for the midwater trawling should be made lighter than that in the bottom trawling, even if temporary. The authors carried out an experiment to achieve this purpose by attaching a large styropol float on the top of the otter board. In this experiment, underwater weight of the otter board was 630kg and buoyancy of the float was 510kg. To determine the depth and horizontal opening of the otter board, two fish finder was used. A transmitter of 50KHz fish finder was set downward through the shoe plate of otter board to determine the elevation of otter board from the sea bed, and a transmitter of 200KHz fish finder was set sideways on the starboard otter board to be able to detect the distance between otter boards. The obtained results can be summarized as follows: 1. The actual towing speed in the experiment varied 1.1 to 1.8 m/sec. 2. The depth of otter board was within 41 to 25m with float on the top and 45 to 26m without float in case of the warp length 100m, whereas the depth 68-44m with float and 74-46m without float in case of the warp length 150m. This fact means that the depth with float was 9-4% shallower than that without float. 3. The horizontal opening between otter boards was within 34-41m with float and 30-38m without float in case of the warp length 100m, whereas the opening was 44-50m with float and 37-46m without float in case of the warp length 150m. This fact means the opening with float was 10% greater than that without float in case of the warp length 100m, and 15% greater in case of the warp length 150m. 4. The horizontal opening between wing tips by using the otter board with float was 1m greater than by without float in case of the warp length 100m, whereas the opening by with float was 2m greater than by without float in case of warp length 150m. From this fact, it can be estimated that the effective opening area of the net mouth by using the otter board with float could be made 10% greater than by without float in case of warp length 100m, whereas the area with float 20% greater than by without float in case of warp length 150m.

• Korean journal of food and cookery science
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• v.26 no.5
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• pp.603-616
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• 2010

Based on recent dramatic increases in foodborne outbreaks in restaurants, self-managed sanitation systems are now recommended to control contributing risk factors. This study aimed to improve sanitation management practices in restaurants and had two objectives. First, we tried to develop a self-managed sanitation check-list, including risk factors contributing to foodborne illness and Korean food hygiene regulation articles. We also tried to evaluate current sanitation management practices in restaurants according to operation and restaurant type. Thirty restaurants were evaluated by on-the-spot inspectors using an auditing tool consisting of four dimensions, seventeen categories, and forty-one items. Total compliance rate categorized by operation type significantly differed between chain restaurants and self-managed restaurants, with values of 85.5% and 51.6%, respectively. Therefore, self-managed restaurants, which showed the lowest compliance rate of below 30.0%, need more strict control to improve current unsanitary management practices, specifically relating to 'sterilization of knives, chopping boards, and wiping cloths', 'sanitation training', 'not allowing access into the kitchen to outsiders', 'handling of food or utensils on shelves at a 15 cm distance away from floor', 'prevention of cross-contamination of cooked foods or vegetables', and 'records of kitchen access or inspection'. Thus, an effective food sanitation system is essential and should be implemented to improve the existing sanitary conditions in restaurants. However, the most important factor to achieving food sanitation management objectives is food handlers' self-motivation.

• Korean Journal of Environmental Agriculture
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• v.13 no.3
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• pp.241-250
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• 1994

This research was carried out to investigate how the growth of corn was affected by the heavy metal contents in soils near the old zinc-mining sites, by analyzing correlation between the growth of corn and heavy metal contents in soils collected from Yonghari Ilwoulmyun YongyangGun in Kyeongpook province in 1993. The results obtained were summarized as follows. 1. The contents of heavy metals such as Zn, Cu, Pb, Cd, and as in the Youngyang area were very high compared with those in a normal area. Heavy metal contents in soils collected from $2.0{\sim}2.5Km$ distance from the mining area were the highest, and those from 3.0 Km than those from 1.5 Km were even higher. 2. For heavy metal contents in leaves of all surveyed crops, Zn, Pb, Cu and As were the highest in soybean, followed by corn and rice. 3. Growth parameters of corn in polluted fields were comparatively poor and heavy metal contents in soils of the respective sites were higher than those in fields where rice was cultivated 8 years ago and irrigation was not done previously. 4. Heavy metal contents in the leaf part of corn plant showed a similar tendency to those in soils, being the highest among the different parts of corn plant, and they were in the decreasing order of Zn > Cu > As > Cd > Pb in each part. But the differences of metal contents in each part varied. 5. Generally, a negative relationship existed between the growth of corn and heavy metal contents in soil, of which Cu and Pb were significantly correlated with plant height, ear height, diameter of stem, ear length and yield of corn. 6. There existed a positive correlation between the contents of Pb,Cd and As in soils and those in the different parts of corn plant. The higher contents of Pb, Cd, and As in soil, the more those in corn plant incressed. The contents of Pb and As in corn grains showed a highly significant positive correlation with Cd and As contents in soils.