• Korean Journal of Plant Resources
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• v.19 no.6
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• pp.680-686
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• 2006

This experiment was conducted on wild vegetables; Gondalbi (Cirsium setidens), Deoduck (Codonopsis lanceolata Trautv.), and Jandae (Adenophora triphylla var. Joponica Hara) seed to study whether priming with deep sea water results in enhancement of seed germination and identify the optimum concentration of the priming solution, and duration of priming. Seeds were primed with 5 various concentrations (5%, 10%, 15%, 20% and 30%) of deep sea water (DSW) in 12 hours, 24 hours, and 48 hours at $24^{\circ}C$. Since Jandae had seed dormancy, it was kept for four weeks in refrigerator at $2^{\circ}C$ after priming treatment. In Deoduck, 5 percentage DSW priming significantly improved the early germination percentage, radicle length, and plumule emergence percentage. Among the priming period of treatments, 24 hours priming showed better performance in this treatment whereas, in Jandae, 12 hours priming with 10 percentages DSW significantly improved the germination percentage and germination rate. This treatment had increased the final germination percentage by 54%, 15% and 40% compared with control, plain water and $KNO_3$ priming respectively. But in Gondalbi, priming did not improve the germination of seed. However, among the priming treatments, 12 hours priming with 3% $KNO_3$ and 20% DSW gave better performance. In both the wild vegetables; Deoduck and Jandae, priming in deep sea water had improved the germination percentage and germination rate as compare to plain water, $KNO_3$, and without priming treatment. Hence the best seed priming treatment on Deoduck and Jandae are 24 hours with 5% DSW and 12 hours with 10% DSW respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.7
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• pp.1030-1034
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• 2003

Two experiments of four-week duration were conducted to investigate the effect of caecectomy on the intestinal characteristics, body weight gain and gas production in the caeca of White Roman goslings. In experiment I, forty eight 2-wk-old female goslings with similar body weight were randomly divided into four treatments: sham (SHAM), left side caecum removed (LSCR), right side caecum removed (RSCR) and both caeca removed (CAECECTOMY). Smimilarly, experiment II was conducted with twelve 5-wkold male goslings in two treatments: SHAM and CAECECTOMY. Free choice water with ad libitum feed was provided during experiment. At the end of experiment I, goslings were sacrificed and gut length and weight were determined. At 7 and 9 wks of age, birds in experiment II were subjected to respiration calorimetry studies. In both experiments, final body weights were not affected by caecectomy. Results of experiment I indicated that caecectomy did not significantly affect the relative weight (g/100 g BW) of gizzard, small intestine, rectum and colon (p>0.05); however, the relative length of colon and rectum did increase (p<0.05). The remaining caecum did not show compensatory growth in both LSCR and RSCR treatments. In experiment II, results indicated that the average enteric methane production from the caecetomised goslings was significantly lower than that from the bird in SHAM goslings (p<0.05). In comparison with SHAM goslings, calorific loss from entric methane in caecetomised birds was lower (p<0.05). There was no effect of age on methane production. The enteric nitrous oxide production in caeca of goslings was very low with no significantly different between two treatments.

• Earthquakes and Structures
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• v.8 no.3
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• pp.779-799
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• 2015

The slosh height and the possibility of water spill from rectangular Spent Fuel Storage Bays (SFSB) and Tray Loading Bays (TLB) of Nuclear power plant (NPP) are studied during 0.2 g, Safe Shutdown Earthquake (SSE) level of earthquake. The slosh height obtained through Computational Fluid dynamics (CFD) is compared the values given by TID-7024 (Housner 1963) and American concrete institute (ACI) seismic codes. An equivalent amplitude method is used to compute the slosh height through CFD. Numerically computed slosh height for first mode of vibration is found to be in agreement the codal values. The combined effect in longitudinal and lateral directions are studied separately, and found that the slosh height is increased by 24.3% and 38.9% along length and width directions respectively. There is no liquid spillage under SSE level of earthquake data in SFSB and TLB at convective level and at free surface acceleration data. Since seismic design codes do not have guidelines for combined excitations and effect of higher modes for irregular geometries, this CFD procedure can be opted for any geometries to study effect of higher modes and combined three directional excitations.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.6
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• pp.760-767
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• 2014

An experimental study is carried out to investigate the effect of jet stream in the gab of rectangular cylinders with different length in a parallel arrangement by using PIV method in a circulating water channel. The height(h) of the rectangular cylinder and the gap between the cylinder is 10mm, and the width(B) which is 300mm. The length of the model for flow direction was applied to 30mm, 60mm, 90mm & 120mm, The aspect ratio of a model on the basis of height(H=30mm) is 1, 2, 3 and 4. Reynolds number $Re=1.4{\times}10^4$, $Re=2.0{\times}10^4$, $Re=2.9{\times}10^4$ based on the height(H) of model for the distance of tidal distributions as of water depth have been applied during the whole experiments. The measurement area was set to 5H rear of the cylinder. As a result, Vortex size in the wake area were increased as velocity increased. and high aspect ratio increased through-flow velocity component in the near wake. Velocity deficit increased highly after near-wake area and low aspect ratio.

• Korean Journal of Ecology and Environment
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• v.36 no.4 s.105
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• pp.447-454
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• 2003

Aluminum coagulant was applied to two eutrophic lakes (Lake Sukchon, in Seoul, and a pond on the campus of Kangwon National University), to precipitate suspended particles and phosphate from the water column. Aluminum sulfate (alum) was used for seven treatments and polyaluminum chloride (PAC) was used for one treatment. The effect of treatment varied depending on the dose of alumium coagulant. Particles and phosphate were completely precipitated from the water column with a dose of 10.0 mgAl/l. Partial removal was observed at doses of 3.3 and 1.8 mgAl/l, but not at 0.45 mgAl/l. Therefore, coagulant should be applied at a dose over the threshold in order to remove particles effectively, which seems to be between 1.8 and 10.0 mgAl/l. The length of treatment effect was determined by new inputs of nutrients and particles from external sources. Renewal of pond water by stream water caused recovery of algal growth in Lake Sukchon, and rainfall runoff and ground water pumping caused a return of turbid water in the campus pond. During treatment there was no sign of decreasing pH, or harmful effects on fish or mussels. Aluminum coagulant may be an economically feasible alternative for water quality improvement when the external control of pollutant sources is difficult. However, repeated application is required when there is a renewal of lake water or new input of nutrients.

• Journal of Navigation and Port Research
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• v.27 no.3
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• pp.247-252
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• 2003

This paper is mainly concerned with the assessment of safe navigation between ships moving each other in restricted waterways. The numerical simulation of manoeuvring motion was conducted parametrically to propose an appropriate safe speed and distance, which is required to avoid sea accident under the different conditions, such as ship-velocity ratios, ship-length ratios, separation and stagger between ships. As for the calculation parameters, the ratios of velocity difference between two ships were considered as 0.6, 1.2, 1.5 and the ones of ship-length difference were regarded were regarded as 0.5, 1.0, 1.18. From the inspection of this investigation, it indicates the following result. Firstly, the separation between ships is more needed for the small vessel, compared to the large vessel. Secondly, the lateral distance between ships is necessarily required for the velocity ration of 1.2, compared to the cases of 0.6 and 1.5. The manoeuvring characteristics based on this investigation will be very useful for keeping the safety of navigation from the practical point of ships design and traffic control in confined water.

• Journal of Ocean Engineering and Technology
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• v.27 no.3
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• pp.29-35
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• 2013

The exploration areas for maritime resources such as oil and natural gas have gradually moved to deep sea areas. It has become difficult to use existing fixed marine structures, which are very costly to build, because that have reached the uppermost economic limit. Therefore, floating marine structures and flexible marine structures are preferred. In particular, slender bodies such as risers and pipes are important parts of ocean depth marine structures. These slender bodies have more flexible structural characteristics in deep water areas because their overall length becomes longer and thediameter/length slenderness ratio gets smaller. In addition, the dynamic behavior of slender bodies becomes complicated as external forces such as tides and waves act on it directly. In this study, in order to solve these problems, we performed model tests in a 2-D wave basin using flexible slender bodies with different modulus of elasticity values. As a result, we compiled statistics and compared the behaviors of flexible slender bodies with respect to the effect of the modulus of elasticity. We expect that the results could be used as reference data for the design of structures with flexible elements.

• International Journal of Industrial Entomology and Biomaterials
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• v.10 no.2
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• pp.107-117
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• 2005

Oral supplementation of minerals mixture of potassium bromide and nickel sulphate on $CSR_2,\;CSR_4\;and\;CSR_2{\times}CSR_4$ crossbreed races with different concentrations (70, 110 and $160\;{\mu}g/ml$) were fed to the fifth instar larvae. Two of the four normal feeds per day was substituted with treated leaves fed to silkworm at fifth instar larvae. The controls were fed with the leaves sprayed with distilled water and normal leaves. The $CSR_4$ race treated larvae showed a significant increase in silkgland weight, cocooning percentage, female cocoon weight, male cocoon weight, male cocoon shell weight, male cocoon shell ratio, filament length, filament weight, denier, fecundity, number of eggs per ovariole and length of the ovariole when compared with those of the corresponding parameters of the carrier control, whereas in $CSR_2\;and\;CSR_2{\times}CSR_4$ crossbreed races showed a significant increase in larva1 weight and other parameters similar to that of $CSR_4$ race. The results suggested that the silkgland showed good response to minerals mixture of potassium bromide and nickel sulphate only in $CSR_4$ race when compared with those of other two races of the silkworm, B. mori.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.9 no.1
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• pp.25-30
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• 2013

The periodic inspection of piping and pressure vessels welds in nuclear power plant has to provide reliable result related to weld flaws, such as location, maximum amplitude response, ultrasonic length, height and finally the nature or flaw pattern. The founded flaw in ultrasonic inspection is accepted or rejected based on these data. Specially, the amplitude of flaw response is used as basic parameter for flaw sizing and it may cause some deviation in length sizing result. Currently the ultrasonic inspections in nuclear power plant components are performed by specific inspection procedure which describing inspection technique include inspection system, calibration methodology and flaw characterizing. To perform ultrasonic inspection during in-service inspection, reference gain should be established before starting ultrasonic inspection by the requirement of ASME code. This reference gain used as basic criteria to evaluate flaw sizing. Sometimes, a little difference in establishing reference gain between calibration and field condition can lead to deviation in flaw sizing. Due to this difference, the inspection result may cause flaw sizing error. Therefore, the objective of this study is to compare and evaluate the ultrasonic amplitude difference between air filled and water filled pipe in nuclear power plant. Additionally, the accuracy of flaw sizing is estimated by comparing both conditions.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.3
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• pp.493-499
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• 2004

The dominant effect of the interaction between vortices, generated by the addition of the Leading Edge Extension(LEX) in front of the wing, was well observed in this experiment. In this study, systematic approach by PIV experimental method within a circulating water channel was adopted to study the fundamental characteristics of induced vertex generation, development and its breakdown appearing on a delta wing model with or without LEX in terms of four angles of attack($15^{\circ}$, $20^{\circ}$, $25^{\circ}$, $30^{\circ}$) and six measuring sections(30%, 40%, 50%, 60%, 70%, 80%) of chord length. Distributions of time-averaged velocity vectors and vortices over the delta wing model were compared along the chord length direction. High-speed CCD camera which made it possible to acquire serial images is able to get the detailed information about the flow characteristics occurred on the delta wing. Especially quantitative comparison of the maximum vorticity featuring the induced pressure distribution were also conducted to clarity the significance of the LEX existence.