• Ocean Systems Engineering
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• v.6 no.4
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• pp.325-344
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• 2016

Using 3D computational fluid dynamics techniques in recent years have shed significant light on the Vortex Induced Vibrations (VIV) encountered by deep-water marine risers. The fatigue damage accumulated due to these vibrations has posed a great concern to the offshore industry. This paper aims to present an algorithm to predict the crossflow and inline fatigue damage for very long (L/D > $10^3$) marine risers using a Finite-Analytical Navier-Stokes (FANS) technique coupled with a tensioned beam motion solver and rainflow counting fatigue module. Large Eddy Simulation (LES) method has been used to simulate the turbulence in the flow. An overset grid system is employed to mesh the riser geometry and the wake field around the riser. Risers from NDP (2003) and Miami (2006) experiments are used for simulation with uniform, linearly sheared and non-uniform (non-linearly sheared) current profiles. The simulation results including inline and crossflow motion, modal decomposition, spectral densities and fatigue damage rate are compared to the experimental data and useful conclusions are drawn.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.2
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• pp.680-688
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• 1996

In this paper, the unsteady state calculational model is proposed for the thermal stratification analysis in the feedwater line of the PWR plant. By defining dimensionless parameters in the two-dimensional polar coordinate system and applying SIMPLE algorithm, the temperature and flow profiles due to the thermal stratification are obtained. Base on the fact that the most significant condition occurs when the fluid temperature difference between the piping ends reaches as high as 166.deg. C, the present result shows that max. Dimensionless temperature difference of 0.6 (about l00.deg. C) obtained between hot and cold sections of pipe wall at dimensionless time 47.0.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.3
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• pp.484-490
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• 1996

Physicochemical changes were determined for the boiled-dried anchovies packaged in a laminated film(nylon 15${\mu}{\textrm}{m}$/polyethylene 100${\mu}{\textrm}{m}$) and stored for one year at ambient and cooling(5~1$0^{\circ}C$) temperatures after gamma irradiation. Lipophilic and hydrophilic browning pigments increased with storage time particularly at ambient temperature, even though initial 5 kGy irradiation did not affect the formation of pigments significantly. This results were confirmed by the instrumental color determinations, Hunter color L, a, b and ΔE. With respect to changes in relative fatty acid compositions, storage period and temperature were more influential factors than gamma irradiation. Irradiation at 5 kGy induced insignificant changes in the total flavor profiles of stored anchovies, which were mainly composed of n-dodecanal(26.7%), n-pentadecane(22.2%), n-octanal(4.9%) and 2-pentylfuran(3.4%).

• Korean Journal of Pharmacognosy
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• v.49 no.3
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• pp.189-202
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• 2018

Hop cones (Humuli Strobili) are the female inflorescences of hop plants (Humulus lupulus L.) belonging to the family Cannabaceae. They have been used as herbal remedies to treat mood and sleep disturbances, and mainly to add as a bittering ingredient in brewing process. Considerable interests on pharmacological and biological activities of hop cones have been focused on their major constituents, namely, phloroglucinols (humulone, lupulone), terpenes (myrcene, humulene), and prenylated flavonoids (xanthohumol, isoxanthohumol, 6-prenylnaringenin, and 8-prenylnaringenin). The present review describes and discusses biological activity profiles of these major compounds in the hop cones.

• Journal of Applied Biological Chemistry
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• v.50 no.3
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• pp.127-131
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• 2007

The properties of two cultivars of japonica rice, Odae (early ripening variety) and Ilpum (late ripening variety), were compared. They grew on MS (Murashige and Skoog) medium but the growth of both cultivars was strongly retarded by 50 mM or more salt. There was no clear difference between the growths of seedlings of the two cultivars for the first 24 h after germination. The amylopectin chain-length profiles of the two cultivars did not differ significantly, and amylopectin content was estimated at $16.0{\pm}0.4%$ in cv. Odae and $16.4{\pm}0.4%$ in cv. Ilpum. A total of 114 RAPD (randomly amplified polymorphic DNA) fragments ranging from 0.4 to 2.5 kb were isolated from the two cultivars, 61 from cv. Odae and 53 from cv. Ilpum, indicating that there is little genetic variation between them.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1545-1547
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• 2009

The fiber-rich fractions including enzyme treated insoluble dietary fiber, alcohol insoluble solid, and water insoluble solid were prepared from the peel of soft ripe persimmon, and to evaluate and compare the yields, proximate compositions, monosaccharide profiles, and functional properties. The results showed that uronic acid was the main sugar followed by glucose, which indicated that all insoluble fibers were mainly composed of pectic substances and cellulose. The presence of xylose and fucose indicated the occurrence of hemicellulose. All fiber-rich fractions were exhibited high yield and functional properties. Thus, the peel of ripe persimmon could be used as fiber supplements.

• Carbon letters
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• v.1 no.2
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• pp.82-86
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• 2000

The present research was undertaken to evaluate the possibility of water purification filter with activated carbon fibers (ACFs) using a very low cost precursor consisting of phenolic resin coated on glass fibers. The simplified procedure involving coating, curing and activation and a very low cost glass fiber as a raw material were adopted in order to reduce manufacturing cost. The breakthrough curves of the manufactured ACFs and the commercial activated carbon (AC, Calgon F-200) were investigated in the initial concentration range from 19 to 49 ppm for benzene, toluene and ethylbenzene. From breakthrough profiles, the manufactured ACFs had significantly faster adsorption kinetics than the AC. Especially the benzene breakthrough curves, the manufactured ACF (13 g of ACF with 32% of carbon on the glass) was over the limited level (5 ppb) after flowing of 32 l at initial concentration of 15 ppm, while the commercial AC was shown about 3 ppm in initial adsorption.

• Journal of Magnetics
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• v.3 no.4
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• pp.123-126
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• 1998

The magneto-impedance (MI) has been measured in the annealed Co66Fe4Ni1B14Si15 amorphous ribbon for the evaluation of anisotropy field. MI at the frequency of 10 MHz is related to the transverse permeability from rotational magnetization depending on the local anisotropy field. MI varies sensitively with the annealing temperature, reflecting the change of anisotropy field distribution. The local anisotropy fields evaluated from MI Profiles are discussed in terms of the magnetic softness and microstructural change by the annealing.

• Clinical and Experimental Reproductive Medicine
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• v.29 no.4
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• pp.279-285
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• 2002

Objective : To evaluate the difference between estrogen only therapy and estrogen-androgen combination therapy in surgical menopause patients. Materials and Method: Surgical menopause patients received 0.625 mg conjugated equine estrogens or 0.625 mg conjugated equine estrogens plus 1.25 mg methyltestosterone for 2 years. Bone mineral density, menopausal symptoms, lipoprotein profiles were measured. Results: Both groups showed increased bone mineral density. In the combination group, total cholestero l, high density lipoprotein cholesterol and triglycerides decreased. In the estrogen only group, low density lipoprotein cholesterol decreased but high density lipoprotein cholesterol increased significantly. In both groups, menopausal symptoms were much improved. Side effects were easily tolerated in both groups. Conclusions: Estrogen-androgen combination therapy had comparable benefits compared with estrogen only therapy.

• Journal of Plant Biology
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• v.29 no.4
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• pp.255-262
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• 1986

Developmental changes of chlorophyll-protein (CP)-complex and plastid membrane proteins during the greening of rape (Brassica napus L.) cotyledons were examined in order to investigate the effect of benzymladenine (BA) on plastid development. The formation of CP-complexes was slightly promoted by BA treatment in early greening stage, at 24 h and 48 h after illumination. However, BA inhibited the development of CP-complexes at 72 h after illumination. On the profiles of plastid membrane proteins with greening time, it was found that the 24 kd protein was increased and the 56 kd protein was decreased in both water control and BA-treated cotyledons. However, the above two traits were retarded under BA treatment, respectively. From the obtained result, plastid development of rape cotyledon during greening was partially affected by interaction between light and BA dependent on its physiological age.