• Journal of the Korean Applied Science and Technology
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• v.12 no.1
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• pp.43-46
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• 1995

The antioxidative effect of ethanol extract of ginger on mackerel pike(Colorabis saira) flesh was investigated by periodically measuring TBA value and perioxide value(POV) during storage. The ethanol extract of ginger was added to minced mackerel pike flesh and the fish oil by concentration(2%, 4%, 6%, 8%). Then the minced flesh was storaged at $-5^{\circ}C$ and the fish oil was incubated at $40^{\circ}C$. The TBA values of minced flesh were approximately increased in inverse proportion to concentration of ginger extract. Peroxide values were attended with the same effect as TBA value in the aggregate. In addition, The relationship between $TBA_{37^{\circ}C-2hrs}$ of the minced flesh and their lipid oxidation during storage at -$5^{\circ}C$ for 4 weeks was observed(r=O.98). $TBA_{37^{\circ}C-2hrs}$ can be expressed as the susceptibility to lipid oxidation of minced mackerel pike flesh during storage. In the results, the antioxidative effect of alcohol extract of ginger on mackerel pike flesh was observed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.1
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• pp.98-102
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• 2020

We examined the comparative spawning ecology of daggertooth pike conger Mureanesox cinereus and common pike conger M. bagio in the South Sea of Korea from May 2018 to December 2019. In the South Sea of Korea, the mean total length (TL) of M. cinereus was significantly smaller than that of M. bagio. The sex ratios of both species were skewed toward females. The spawning period of M. cinereus was from June to October, while the spawning period of M. bagio was from August to October. The lengths at 50%, 75%, and 97.5% sexual maturity of M. cinereus females were estimated as 54.6 cm, 60.4 cm, and 74.1 cm TL, respectively. It was not possible to estimate lengths at sexual maturity for M. bagio in the South Sea of Korea due to the absence of immature stages.

• Korean Journal of Applied Biomechanics
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• v.14 no.1
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• pp.1-12
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• 2004

The purpose of this study is to provide training materials for practical use by investigating the kinematical variables of the successful landing by the type of the salto backward such as Tuck, Pike. For this study, the subjects are 4 male national gymnasts using 3-dimensional cinematographic method. Based on the results of this study, the conclusions are drawn as follows. 1. In flight phase, Tuck and Pike show fast extension after completing minimum angle of hip joint passing through the peak. It is very important factor to control body with gaining time before landing while decreasing the velocity of flight rotaion. 2. In Landing phase, the angles of each joint for successful landing are shown as $92deg{\sim}100deg$ for knee angle, $52deg{\sim}57deg$ for hip angle, and $56deg{\sim}70deg$ for shoulder angle. 3. Tuck and Pike dramatically decrease the height of COG, and horizontal/vertical velocity of COG from TD to LD. Also, it is shown that the knee angle, the hip angle and the shoulder angle decrease drastically. On the other hand, the angular velocity of trunk rotation shows negative direction and due to this, the angle of trunk rotation is shown as re-flexion.

• Korean Journal of Applied Biomechanics
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• v.27 no.3
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• pp.157-164
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• 2017

Objective: The purpose of this study was to investigate kinematic differences in back pike somersault in platform diving according to skill level and to apply the findings to improve performance. Method: Korean divers participating in this study were divided into a skilled group (age: $21.6{\pm}4.16y$, height: $1.68{\pm}0.03m$, weight: $62.0{\pm}3.94kg$, career: $12.6{\pm}5.13y$) and a less-skilled group (age: $20.6{\pm}2.7y$, height: $1.72{\pm}0.05m$, weight: $64.8{\pm}6.76kg$, career: $12.2{\pm}2.49y$) and an independent t-test was performed to analyze differences between groups at the moment of takeoff. Results: The two groups showed significant differences in displacement and velocity of center of mass (COM), takeoff angle, hip joint angle, knee joint angular velocity, and hip joint angular velocity at the takeoff (p<.05), and significant differences in displacement of COM, hip joint, and ankle joint during flight (p<.05). Conclusion: For a successful back pike, the COM should rise quickly in the vertical direction and the hip joint angle and angular velocity should increase. To improve performance, the back pike turn should be practiced on the ground before an attempt on a 10-m platform, to stretch the ankle and knee joints and enable quick flexion of the hip joint when turning in flight.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2006.06a
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• pp.71-74
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• 2006

무선 센서 네트워크는 미래의 유비쿼터스 컴퓨팅에서 핵심적인 역할을 할 것으로 알려져 있으며, 그에 따라 센서 네트워크에서의 안전한 통신도 중요한 문제로 떠오르고 있다. 이러한 센서 네트워크에서의 안전한 통신을 위해서는 각 센서 노드 사이에서의 안전한 키 관리 프로토콜이 필수적이다. [1]에서는 기존에 제안된 key-predistribution 방식보다 효율적인 키 합의 프로토콜을 제안했다. 그런데, [1]에서 제안된 PIKE 프로토콜에서 각 센서 노드 사이의 통신에 대한 가정을 현실적으로 바꾸면 보다 효율적인 프로토콜을 얻을 수 있다. 네트워크의 전체 센서 노드의 수를 n이라고 했을 때, [1]에서 제안된 프로토콜에서 각 센서 노드의 메모리 소요량은 O($\sqrt{n^}$)이나, 본 논문에서는 키 합의 매개 노드의 수와 메모리 소요랑 사이의 trade-off 관계를 보이고 최적의 프로토콜을 구성하는 방법에 대해 논의한다.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.2
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• pp.145-153
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• 1995

Effects of lime application levels(0, 10, 50, 100, and 300kg/10a) on three alfalfa cultivars(Dekalb brand 120, Pike, Pioneer brand 5929) were analyaed with respect to the growth, dry matter yield, and inorganic composition of the plants at three cutting periods. Major chemical properties of the soils were also analyzed. Response of the plant height to the lime application level was variable among the cultivars, showing the order of 50>100>300>10>0kg/10a in Dekalb brand 120, 50>100>10>300>0kg/10a in Pike, and 10>50>300>0>100kg/10a in Pioneer brand 5929. The order of dry matter yield response to the lime application level was 50>300>100>10>0kg/10a in Dekalb brand 120, 50>10>300>100>0kg/10a in Pike, and 50>100>10>0>300kg/10a in Pioneer brand 5929. Total dry matter yields at 50kg/10a lime application level were higher than those at any other levels in all the cultivars. Neither a specific pattern nor a significant change in inorganic composition of the plant was found for the lime application levels and cutting times, Soil chemical properties and composition remained with little change after the experiment except the soil pH, which was increased with the lime application level.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.48-54
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• 1989

This study was conducted to select the best adapted alfalfa cultivars among 32 introduced alfalfa cultivars in the Korean environmental condition. Plant height and dry matter yield per cultivar were determined. On the point of plant height, seven high ranked cultivars among the 32 alfalfa cultivars in high order were Diamond> Milkmaker> Arrow>Chalienger>Sapphire > Dekalb brand 135> LS-1920. and seven low ranked cultivars in low order were Pioneer brand 5929> Maxidor> Dekalb brand 167> Pierce> Blazer> Raidor> Pioneer brand 532. Seven high ranked cultivars from 32 alfalfa cultivars on the dry matter yield in high order were Pike>LS-1920>Challenger>Salute>Diamond>Decathlon>Pioneer brand 581, and seven low ranked cultivars in low order were Maxidor>Pioneer brand 5929>Pioneer brand 532>Florida 77> Pierce> Magnum> Blazer. Dry matter yield per cultivar was also greater when alfalfa cultivar was appeared higher plant height compared with those which were lower plant height. Leading cultivars for plant growth and yield under the Korean environmental condition were Pike, LS-1920, Challenger, Salute, Diamond among the 32 alfalfa cultivars. All those cultivars except Challenger cultivar are Semi-dormant which can be well grown under moderate temperatures.

• Korean Journal of Ichthyology
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• v.36 no.2
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• pp.129-138
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• 2024

This study examines the osteological development of the Pike gudgeon, Pseudogobio esocinus in the cranial, vertebral, caudal, pelvic and pectoral girdle for the purpose of taxonomic and aquacultural studies. Adult Pike gudgeon collected from the Boseonggang River were reared at 18.5~19.5℃ (average 19.0℃). At 5 days after hatching (total length (TL) 4.25 mm), the parasphenoid, dentary, centrum of vertebrae and clavicle began to ossify. At 22 days after hatching (TL 6.33 mm), 36 to 38 vertebrae had ossified. At 42 days after hatching (TL 16.71 mm), the majority of the skeleton had ossified. Pike gudgeon exhibited comparable characteristics to other fishes of Gobionidae throughout its development, although it displayed differences in some areas, such as the caudal skeleton and fin supports.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.1
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• pp.76-81
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• 2012

The feeding habits of daggertooth pike conger Muraenesox cinereus were studied using 380 specimens collected in the coastal waters off Goseong, Korea, from June to September, 2011. The M. cinereus ranged from 10.0-23.7 cm in anal length (AL). M. cinereus is a piscivore that consumes mainly fish. Engraulis japonicus was the preferred prey, but its diet also included small numbers of crabs, shrimps, cephalopods, and bivalves. The feeding strategy graphical method revealed that M. cinereus is a specialized feeder with a narrow niche width. All size classes of M. cinereus consumed fish and M. cinereus did not show significant ontogenetic changes in feeding habits. The diet overlap index between size classes was >0.96, indicating high diet similarities. The prey size increased significantly with M. cinereus size.

• Fisheries and Aquatic Sciences
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• v.21 no.3
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• pp.12.1-12.15
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• 2018

A preliminary investigation of length-weight relationship, condition factor and reproductive ecology of African pike fish, Hepsetus odoe, was conducted between June to August 2010 in Lake Eleiyele. A total of 90 samples of the fish species were caught by fishermen using gill nets. The results obtained showed that fish species had isometric growth pattern (contrary to negative allometry expected) with the growth exponent, b value of 2.64, that is not statistically different from 3 and with high statistical power of 0.866 when tested. The mean condition factor, K, was found to be 2.6, indicating that the fish species were in good condition in the study area. For reproductive biology, mean fecundity and gonadosomatic index were found to be 1349 eggs and 3.53% respectively. This study was necessary to fill the knowledge gap and provide information for management and conservation of the investigated species in the lake system. This study recommended that further research needs to be conducted because the sampling was carried out in the rainy season period and within a quarter of a year.