• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.2
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• pp.120-128
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• 2008

Estimation of the gear shape and cross section of sweep at mouth of a bottom trawl net was described and applied to the field experiments obtained with the Scanmar system. The shape of the trawl net from wingend to the beginning of codend was assumed to be part of an elliptic cone of which the cross section was ellipse, and that of the float rope be of form $y_f=a_fx^{bf}$. In case of a bottom trawl with warp 180m long, the radius of ellipse, the cross section of sweep at mouth, the eccentricity of the ellipse, the inclination angle of float rope and the contribution of the side panel to net height were estimated in accordance with towing speed. The horizontal radius of the upper ellipse increased with increasing towing speed, the eccentricity of it became slightly bigger as increasing the towing speed which meant the shape of it being flat. And the inclination angle of the float rope was about between 7 and 12 degrees in case of the above bottom trawl.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.43 no.4
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• pp.347-354
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• 2007

This paper describes on the real-time monitoring of net setting and hauling process for fishing operations of Danish seine vessels in the southern waters of Korea as an application of a PC based ECDIS system. Tracking of fishing process was performed for the large scale Danish seine vessel of G/T 90 and 350 PS class using the fishing gear which the length of net, ground rope, head rope and sweep line including warp in both sides were 86m, 104m, 118m and 3,200m, respectively. Tracking information for net setting and hauling process was continuously recorded for 23 fishing operations performed on November and December, 2003. All measurement data, such as trawl position, heading, towing course and past track which was individually time stamped during data acquisition, was processed in real time on the ECDIS and displayed simultaneously on the ENC chart. The results indicated that after the separation of a marker buoy from Danish seiner, the averaged running speed of vessel and the averaged setting period while shooting the seine on the course of diamond shape to surround the fish school in the 23 fishing operations were 8.3 knots and 13.1 minutes, respectively. And with the maker buoy taken on board, the averaged running speed of vessel and the averaged towing period while closing the seine on the straight route was 1.0 knots and 47.0 minutes, respectively. After the closing stage of hand rope, the hand rope was towed by the averaged speed of 2.2 knots during the 13.0 minutes. The average area for route of diamond shape swept by sweep lines of the seine in 23 fishing grounds was $709,951.6m^2$. Further investigation is also planed to provide more quantitative tracking information and to achieve more effective surveillance and control of Danish seine vessels in EEZ fishing grounds.

• Korean journal of applied entomology
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• v.27 no.2
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• pp.111-116
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• 1988

Fruit piercing moths were collected at every other at orchaed(16.5ha) planted with plum, peach and pear, and surrounded by forest in Gyeongnam province from jun to September in 1987. Four black light (BL) traps were lightened to attract the moths from sunset to sunrise and sweep net was also used to catch the moths on fruit and around fruit trees from 22 to 23 o'clock, 20 minutes per fruit tree species. Forty-one species, including 15 primary piercing species(PPS) and 22 secondary piercing species (SPS), from 3 families were collected and identified as fruit piercing moths. Among them, 16 species are newly recorded as fruit piercing moths in Korea. O. emarginata, L. juno, P. stuposa, C. lata and O. excavata were diminant species of PPS, comprising 86.7% of the whole PPS. Dominant species of SPS were A. ipsilon, M. turca, S. retorata, A. livida and T. oldenlandiae, comprising 80.5% of the whole SPS. The ratios of PPS to the whole fruit piercing moths collected by BL traps and net were sweep 15.2% and 79.7%, repectively. By sweep net L. juno, P. stuposa, and O. emarginata was also captured in a large numbers on peach, C. lata was on plum, and S. retorata was on pear.

• Journal of Forest and Environmental Science
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• v.35 no.4
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• pp.263-267
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• 2019

Two newly recorded small orb weavers, Araneus yasudai Tanikawa, 2001 and Neoscona flavida sp. nov., with characteristic epigynal scape belonging to Araneidae are described with measurements and morphological illustrations from Korea. Both species were collected with sweep net between shrubs and bushes in mountain forest and between reeds in reclaimed land, respectively.

• Korean Journal of Environmental Biology
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• v.37 no.3
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• pp.367-371
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• 2019

Many spiders belonging to Enoplognatha Pavesi, 1880 and Parasteatoda Archer, 1946 of Theridiidae were collected with sweep net between shrubs and bushes in the mountain forest during a survey of the mountain spider fauna. Among the spiders collected, male Enoplognatha gramineusa Zhu, 1998 and female Parasteatoda ryukyu (Yoshida 2000) were recognized as newly recorded spiders to Korean spider fauna. The present work describes these two spiders with measurements and morphological illustrations.

• Journal of Species Research
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• v.4 no.1
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• pp.57-59
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• 2015

Paraplectana sakaguchii Uyemura, 1938 is a ultra rare species belonging to Araneidae worldwide. This species was collected by sweep net between the shrubs at the foot of mountainous region in August, 2012. This species is briefly described and illustrated in this report. The spider genus Paraplectana is also newly recorded to Korean spider fauna.

• Korean Journal of Environmental Biology
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• v.41 no.1
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• pp.14-17
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• 2023

A male Spheropistha melanosoma Yaginuma, 1957 from Korea in the family Theridiidae Sundevall, 1833 is described with measurements and morphological photos of the diagnostic characteristics. This species was collected with a sweep net around arable lands in a mountainous mixed forest during the investigation of spider fauna on Ulleungdo Island in 2019.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.32 no.1
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• pp.33-41
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• 1996

In order to obtain the most favourable classification system for fishing gears, the problems in the existing systems were investigated and a new system in which the fishing method was adopted as the criterion of classification and the kinds of fishing gears were obtained by exchanging the word method into gear in the fishing methods classified newly for eliminating the problems was established. The new system to which the actual gears are arranged is as follows ; (1)Harvesting gear \circled1Plucking gears : Clamp, Tong, Wrench, etc. \circled2Sweeping gears : Push net, Coral sweep net, etc. \circled3Dredging gears : Hand dredge net, Boat dredge net, etc. (2)Sticking gears \circled1Shot sticking gears : Spear, Sharp plummet, Harpoon, etc. \circled2Pulled sticking gears : Gaff, Comb, Rake, Hook harrow, Jerking hook, etc. \circled3Left sticking gears : Rip - hook set line. (3)Angling gears \circled1Jerky angling gears (a)Single - jerky angling gears : Hand line, Pole line, etc. (b)Multiple - jerky angling gears : squid hook. \circled2Idly angling gears (a)Set angling gears : Set long line. (b)Drifted angling gears : Drift long line, Drift vertical line, etc. \circled3Dragged angling gears : Troll line. (4)Shelter gears : Eel tube, Webfoot - octopus pot, Octopus pot, etc. (5)Attracting gears : Fishing basket. (6)Cutoff gears : Wall, Screen net, Window net, etc. (7)Guiding gears \circled1Horizontally guiding gears : Triangular set net, Elliptic set net, Rectangular set net, Fish weir, etc. \circled2Vertically guiding gears : Pound net. \circled3Deeply guiding gears : Funnel net. (8)Receiving gears \circled1Jumping - fish receiving gears : Fish - receiving scoop net, Fish - receiving raft, etc. \circled2Drifting - fish receiving gears (a)Set drifting - fish receiving gears : Bamboo screen, Pillar stow net, Long stow net, etc. (b)Movable drifting - fish receiving gears : Stow net. (9)Bagging gears \circled1Drag - bagging gears (a)Bottom - drag bagging gears : Bottom otter trawl, Bottom beam trawl, Bottom pair trawl, etc. (b)Midwater - drag gagging gears : Midwater otter trawl, Midwater pair trawl, etc. (c)Surface - drag gagging gears : Anchovy drag net. \circled2Seine - bagging gears (a)Beach - seine bagging gears : Skimming scoop net, Beach seine, etc. (b)Boat - seine bagging gears : Boat seine, Danish seine, etc. \circled3Drive - bagging gears : Drive - in dustpan net, Inner drive - in net, etc. (10)Surrounding gears \circled1Incomplete surrounding gears : Lampara net, Ring net, etc. \circled2Complete surrounding gears : Purse seine, Round haul net, etc. (11)Covering gears \circled1Drop - type covering gears : Wooden cover, Lantern net, etc. \circled2Spread - type covering gears : Cast net. (12)Lifting gears \circled1Wait - lifting gears : Scoop net, Scrape net, etc. \circled2Gatherable lifting gears : Saury lift net, Anchovy lift net, etc. (13)Adherent gears \circled1Gilling gears (a)Set gilling gears : Bottom gill net, Floating gill net. (b)Drifted gilling gears : Drift gill net. (c)Encircled gilling gears : Encircled gill net. (d)Seine - gilling gears : Seining gill net. (e)Dragged gilling gears : Dragged gill net. \circled2Tangling gears (a)Set tangling gears : Double trammel net, Triple trammel net, etc. (b)Encircled tangling gears : Encircled tangle net. (c)Dragged tangling gears : Dragged tangle net. \circled3Restrainting gears (a)Drifted restrainting gears : Pocket net(Gen - type net). (b)Dragged restrainting gears : Dragged pocket net. (14)Sucking gears : Fish pumps.

• Nuclear Engineering and Technology
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• v.46 no.6
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• pp.817-824
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• 2014

To ensure the safety of research reactors, the water level must be maintained above the required height. When a pipe ruptures, the siphon phenomenon causes continuous loss of coolant until the hydraulic head is removed. To protect the reactor core from this kind of accident, a siphon breaker has been suggested as a passive safety device. This study mainly focused on two variables: the size of the pipe rupture and the timing of air entrainment. In this study, the size of the pipe rupture was increased to the guillotine break case. There was a region in which a larger pipe rupture did not need a larger siphon breaker, and the water flow rate was related to the size of the pipe rupture and affected the residual water quantity. The timing of air entrainment was predicted to influence residual water level. However, the residual water level was not affected by the timing of air entrainment. The experimental cases, which showed the characteristic of partical sweep-out mode in the separation of siphon breaking phenomenon [2], showed almost same trend of physical properties.

• Journal of Species Research
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• v.6 no.spc
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• pp.51-53
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• 2017

There are five known species of the genus Tmarus (Thomisidae) in Korea to date: Tmarus horvathi Kulczyn'ski, 1895, Tmarus koreanus Paik, 1973, Tmarus orientalis Schenkel, 1963, Tmarus piger (Walckenaer, 1802) and Tmarus rimosus Paik, 1973. Two females of Tmarus yaginumai Ono, 1977, which was previously only known in Japan, were collected by sweep net between the shrubs at hillocks near the coast of Korea and are described with taxonomic illustrations.