• 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.

• Journal of Korean Tunnelling and Underground Space Association
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• v.4 no.3
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• pp.175-184
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• 2002

Ground reaction curve is very useful information for estimating the installation time of the tunnel support. The ground reaction curve can be estimated by analytical closed form solutions derived in case of circular section and isotropic stress condition. The nature of the ground reaction, however, depends significantly on tunnel configurations. Nevertheless, few purely analytical and experimental studies of this problem due to tunnel configurations appear to have been carried out. Therefore, it is necessary to investigate the influence of tunnel configurations in order to use simply in practical design. This paper describes a numerical study for the intial elastic displacement in the ground reaction curve due to configuration of tunnel excavation. In order to evaluate the applicability of analytical closed form solution in practical design, the parametric studies were carried out by numerical analysis in elastic tunnel behaviour. In the studies, S value, namely configuration factor, defined as the ratio between tunnel height (b) and width (a), varies between 0.5 and 3.0, initial ground vertical stress varies between 5~30 MPa for each S values. The results indicated that the self-supportability of ground is larger in the ground having low S value. It, however, is suggested that the applicability of closed form solution may not be adequate to determine directly the installation time of the support and self-supportability of ground. It should be necessary to perform the additional numerical analysis.

• Current Research on Agriculture and Life Sciences
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• v.3
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• pp.92-98
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• 1985

The experiments were conducted to investigate the activity changes of peroxidase, existence of isoenzyme and the changes of reserved substances in tomato under subatmospheric pressure storage condition. The results obtained were as follows: 1. Soluble fraction showed the highest peroxidase activity and followed by cell wall fraction, mitochondria fraction and ribosome fraction in that order. 2. Peroxidase activity was decreased during the ripening and senescence period in tomato. Especially, peroxidase activity in tomato was higher at a room temperature ($25^{\circ}C$) than at a low temperature ($15^{\circ}C$). The decreasing inclination was similar in both treatment. The peroxidase activity was higher in 380 Torr, than in 570 Torr. 3. At least, two isoperoxidases(Soluble or solubilized) were identified from different extraction procedures. Three of four isoenzymes were recognized from a vertical slab of polyacrylamide gel electrophoresis. 4. The changes of components in tomato under SAP were generally affected by temperature and pressure. Especially, quality of tomato stored at a low temperature ($15^{\circ}C$) and SAP (380 Torr.) was best during storage.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.650-660
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• 2018

The approach slab plays an important role in the driving comfort of the connection section on a bridge. On the other hand, the approach slab only calculates the section force of a simple beam, and does not analyze the behavior. In this study, the unsupported length and settlement of approach slabs of IPM Bridges were examined using structural analysis. First, the section force was calculated by designing a simple beam, according to the length of the approach slab. The structural analysis was conducted to examine the behavior of the unsupported length and settlement. As the result, the bending moment decreased when the unsupported length was increased, and the bending moment increased when the settlement was increased. In addition, the design section force was estimated to be larger than the force of structural analysis, and the design of the approach slab according to the design guideline showed no problem in stability. Nevertheless, the vertical displacement exceeded the maintenance criterion of a 1/200 curve when the settlement exceeded 10 mm regardless of the unsupported length. Therefore, excessive settlement occurs in the reinforced earth retaining wall supporting the approach slab, and the design bending moment may be exceeded. Therefore, strict management is required.

• Magazine of the Korean Society of Agricultural Engineers
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• v.10 no.1
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• pp.1377-1387
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• 1968

In order to measure runoff and soil losses produced in a small test plot during rainfall, it is usually insufficient to use a tank only, necessitating the combined use of a main tank and a subsidiary tank. Accordingly. exact measurement largely depends on how to connect those two measuring tanks. The main purpose of this thesis is to improve the connecting parts of two measuring tanks so as to assure exact measurement of runoff and soil losses. In this experiment, two types of main tank, i. e. A-type and B-type, were used. A-type is a square tank having a flume at its end. At the flume, ten apertures are provided by using metal columns so as to be able to catch one tenth of total muddy flow discharging at the end of the flume, One tenth of total flow is led to the subsidiary tank through a slot sampler fixed to an aperture. B-type differes in that its flume does not have apertures and slot sampler is fixed directly to the end of the flume, other features being the same as those of A-type. Discharge volumes were measured by using weighing tanks and compared. The effect of baffle screen provided in the flume was also observed in connection with exact measurements. In order to keep main tank and its flume in a horizontal position, bolts and nuts mechanism was used. Vertical and horizontal screens were provided in the main to prevent coarse sands coming into the flume. The conclusion derived through this experiment is as follows: (1) The discharge through slot sampler at each aperture is almost the same for A-type. However, it is slightly more than one tenth of total discharge volume. (2) In case that baffle screen is provided in the flume of A-type tank, the discharge volume of slot sampler is less than that of the same type without screen. (3) For B-type tank, slot sampler discharge increases as slot sampler nears toward the center of flume. (4) When baffle screen is provided in the flume of B-type, slot sampler discharge is less than that of the same type without screen, and this phenomenon is more apparent as compared with A-type. (5) In case that the slot width of slot sampler for B-type is one inch, slot sampler discharge exceeds one tenth of total discharge volume. (6) When the slot width for B-type is 15/16 inch and slot sampler is fixed 3/8 inch apart from either flume wall, slot sampler discharge is approximately equal to one tenth of total discharge volume.

• Journal of Korean Society of Forest Science
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• v.105 no.2
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• pp.223-230
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• 2016

This study was carried out to investigate the quarrying and restoration characteristics on quarry in Korea. We researched quarrying and restoration status, analyzed the relationship between restoration area and permitted period, permitted area, quarrying volume, pit slope width, height, and berm width from 55 quarry sites. Most of the quarries were located in the following conditions : mixed forest, average altitude of less than 300 m, average mountain slope of $61^{\circ}$<, hillside, granite and landslide hazard class. Major quarrying characteristics were permitted period of 6~10 years, permitted area of less than 10 ha, quarrying volume of less than $1,000,000m^3$, a stone type of aggregate, a quarrying type of terrace, pit slope of $61^{\circ}$< Most quarries were restored by themselves, and the main restoration type was slope greening. Also, area ratio of flatland, pit slope, and berm was 54.9:39.6:5.5. Ccorrelation analysis showed that quarrying area was positively correlate with quarrying volume (${\alpha}=0.01$), permitted area, pit width, and pit height (a=0.05).

• 한국해양학회지
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• v.29 no.3
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• pp.296-303
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• 1994

Rotating right cylinder of rigid sloping boundaries(top-bottom) is filled with two-layered fluid. External fluid which has the same density as the lower-layer is pumped through the rim boundary at the bottom, and this induces uniform vertical velocity in the interior that produces the Sverdrup type motion such as southward flowing western boundary current with northward interior horizontal motion. The rigid sloping upper boundary meets with lower layer to simulate so called "polar front", and the upper-layer motion influenced by the lower-layer flow has been observed. Barotropic motion in the western part of the basin while baroclinic motion in the eastern half is always present. In particular, both southward flowing eastern boundary flow and western boundary flow meets near the western wall and it induces northward western boundary flow to separate from the boundary With increased ${\beta}$-effect on the upper0layer the width of western boundary decreases and the separated western boundary flow moves into the interior to form an eddy-like motion. Baroclinic Rosebay wave clearly observed in the easter boundary slowly propagates to the west but it seems to be decayed before travelling to the western boundary. A local topograpic effect imposed on the lower-layer causes very sensitive response of upper layer boundary flows. In the east standing0wave0like features are observed in the west whereas the width of the boundary increases without any evidence of the separation of the western boundary flow.This may be due to the gact that even the lower-lauer barotropic motion feels the topography its influence does not propagate into the upper-layer. With large ${\beta}$-effect on the upper-layer,relatively large scale waves whose wavelengths are greater than the internal radius deformation exist in the interior.

• Journal of the Korea Concrete Institute
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• v.27 no.6
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• pp.615-623
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• 2015

The previous strut-and-tie models (STMs) to evaluate the shear strength of squat shear walls with aspect ratio less than 2.0 do not consider the axial load transfer of concrete strut and individual shear transfer contribution of horizontal and vertical shear reinforcing bars in the web. To overcome the limitation of the existing models, a simple STM was established based on the crack band theory of concrete fracture mechanics. The equivalent effective width of concrete strut having a stress relief strip was determined from the neutral axis depth and effective factor of concrete strength. The shear transfer mechanism of shear reinforcement at the extended crack band zone was calculated from an internally statically indeterminate truss system. The shear transfer capacity of concrete strut and shear reinforcement was then driven using the energy equilibrium in the stress relief strip and crack band zone. The shear strength predictions of squat shear walls evaluated from the current models are in better agreement with 150 test results than those determined from STMs proposed by Siao and Hwang et al. Furthermore, the proposed STM gives consistent agreement with the observed trend of the shear strength of shear walls against different parameters.

• Journal of the Korea Concrete Institute
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• v.25 no.6
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• pp.601-612
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• 2013

In the construction of nuclear power plants using massive walls, the use of high-strength re-bars for shear design is necessary to enhance the constructability and economy. In this study, low-rise walls (aspect ratio of 1.0) with grade 550 MPa bars were tested under cyclic loading to investigate the shear capacity and deformation capacity. The test parameters were the grade of horizontal re-bars (550 MPa, 420 MPa), strength of concrete compressive strength (46 MPa, 70 MPa), horizontal/vertical reinforcement ratio, use of lateral confinement hoops, shape of cross section, and failure modes (shear failure before or after flexural yielding). The test results were compared with those of walls with grade 420 MPa bars and predicted strength by current design codes. The results showed that the shear strength of the walls with 550 MPa bars was comparable to that of the walls with 420 MPa bars though the safe margin slightly decreased. ACI 349 provides underestimated shear strength for the walls with 550 MPa bars. In case of the wall with flexural yielding, a large deformation capacity was achieved. This result indicates that the ACI 349 provisions can be safely applied to seismic design of the low-rise walls (aspect ratio of 1.0) with grade 550 MPa bars.

• Journal of the Korean GEO-environmental Society
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• v.17 no.9
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• pp.5-12
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• 2016

Numerical analyses were carried out to simulate tilting control on the suction pile for offshore wind power embedded into cohesive soil and cohesionless soil using finite element software, ABAQUS. A 3-dimensional suction pile was modelled as a wished-in-place pile with $1^{\circ}$ tilted from vertical line. The inner room of suction pile was divided into 3 separate rooms for tilting control, and point load was applied to the center of gravity of a separate room to restore the original position of the suction pile. From numerical analyses, required suction pressure was obtained for desired tilting degree, and the maximum/minimum principle stresses of concrete skirt and the Mises stresses of inner steel wall were collected at original position. It was found that the required suction pressure was about 410 kPa for cohesive soil, and about 1,800 kPa for cohesionless soil.; likewise, obtained stresses were greater for cohesionless soil than cohesive soil.