• ALGAE
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• v.19 no.1
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• pp.23-30
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• 2004

The purpose of this study is to assess the effects that hydraulic-gun-aerators have on cyanobactedial bloom in Sayeon Dam Reservoir in Ulsan City, Korea. A total of nine hydraulic-gun-aerators are in operation at the reservoir withe 100 m spacing between each aerator to control severe cyanobacterial bloom in the dam reservoir. The field studies were performed an total four times at two sampling stations in the reservoir from July to August in 2001. The standing crops of phytoplankton did not changed significantly by the operation. The cell concentration of the cyanobacteria at the surface layer were reduced about 10%, which is a poor result for the dispersing cyandobacteria deeper into the water. The average surface temperature during the study was reduced by 2.0$^{\circ}C$ by the hydraulic-gun-aerators. The effect of the operation on the vertical distribution of DO concentration was clear. However, the hydraulic-gun-aerators were not expected to have an effect in the lowest layer of the hypolimnion. In the study, it was proposed that installation distance between each hydraulic-gun-aerator would be proper when they are apart about 120 m based on DO depth profiles.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.2
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• pp.8-16
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• 2001

To manufacture toilet tissue with ONP (old newspaper), the effect of fractionation fiber (R150, R100, R70 mesh) and bleaching(P, PY), blending (70/30) with MOW(mixed office wastepaper) or WL(white ledger) and the addition of softener on the optical and mechanical properties were studied. Considering the pulp yield, brightness and strengths, fibers of R100 mesh fraction were proper to be produced to toilet paper from ONP. This pulp showed the pulp yield of 76.8%, brightness of 50.2% ISO and tensile index of 21.1 Nm/g. By the bleach with P and PY stages, the brightness of the pulps increased up to 60.3% ISO and 61.8% ISO, respectively. When blended with MOW (57.3% ISO) or WL (76.2% ISO), the brightness of the former increased up to 58.5% ISO, the latter up to 63.6% ISO. The strengths of pulp blended with WL were higher than those of fractionated pulp from 100% ONP, however there was no difference in strengths between fractionated pulp and blended pulp wth MOW. While the addition of softener improved the softness of paper, but it decreased strengths of pulp and extended dispersing time in water.

• Korean Journal of Materials Research
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• v.18 no.11
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• pp.610-616
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• 2008

Oil-based nanofluids were prepared by dispersing Ag, graphite and carbon black nanoparticles in lubricating oil. Agglomerated nanoparticles were dispersed evenly with a high-speed bead mill and/or ultrasonic homogenizer, and the surfaces of the nanoparticles were modified simultaneously with several dispersants. Their tribological behaviors were evaluated with a pin-on-disk, disk-on-disk and four-ball EP and wear tester. It is obvious that the optimal combination of nanoparticles, surfactants and surface modification process is very important for the dispersity of nanofluids, and it eventually affects the tribological properties as a controlling factor. Results indicate that a relatively larger size and higher concentration of nanoparticles lead to better load-carrying capacity. In contrast, the use of a smaller size and lower concentration of particles is recommended for reducing the friction coefficient of lubricating oil. Moreover, nanofluids with mixed nanoparticles of Ag and graphite are more suitable for the improvement of load-carrying capacity and antiwear properties.

• Journal of Korean Medicine for Obesity Research
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• v.8 no.2
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• pp.15-23
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• 2008

The purpose of this study is to introduce oriental medicine music therapy related to the treatment of obesity. Obesity is caused by deficiency of the spleen, retention of phlegm, stagnation of liver Gi. According to the patients' state, the musical instruments should be chosen. In case of deficiency of the spleen, retention of phlegm, and stagnation of liver Gi, the obese patients beat pulsatile instruments to Earth-Gi rhythm, Fire-Gi rhythm, and Wood-Gi rhythm respectively. In addition to beating the musical instrument to the Five Phases rhythm, an oral sound therapy, relieving constraint therapy, and dispersing therapy can be performed. This study describes the theory of oriental medicine music therapy that has a good possibility as a new method of oriental medical treatment. It is necessary to study in measuring the effects after oriental medicine music therapy from now on.

• Journal of Ecology and Environment
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• v.33 no.1
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• pp.19-22
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• 2010

Migratory birds, by crossing significant ecological barriers, carry and may subsequently introduce exotic seeds into new ecological zones during period of migration. The study of epizoochory, which includes seed dispersal by adhesion to bird feathers, has been relatively neglected compared to the study of seed dispersal by frugivores. To determine whether exotic seeds are being imported to stopover islands by migrating birds, and to estimate the quantity of seeds of exotic species being introduced, we examined migratory birds that were captured in mist nets for attached exotic plant diaspores in 2008 and 2009 on Hongdo Island, Korea. From a total of 3,947 birds examined, we found exotic seeds of Japanese Chaff Flowers (Achyranthes japonica) attached to three species of migratory birds (0.08%; Eurasian Bittern Botaurus stellaris, Swinhoe's Rail Coturnicops exquisitus and Oriental Turtle Dove Streptopelia orientalis). Despite the low occurrence of A. japonica seeds on the external parts of birds, the results suggest that migratory birds may be potential dispersing agents for A. japonica, a species that is currently threatening native ecosystems on many islands in Korea.

• The Journal of Korean Medicine
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• v.22 no.1
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• pp.3-9
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• 2001

In the view of oriental medicine, the liver is the general of the army in its function of protecting against the enemy. So this concept is very closely associated to the immunological function. Its relations with immunological function are as follows. 1. The liver produces most of the proteins and converts them with hepatocytes, composes 80% in total reticuloendothelial system with Kuffer cells & endothelial cells and has typical structure of sinusoidal vessels closely related with the blood system. 2. The liver plays an important role in innate immunity with Kuffer cells as well as with the molecules that the liver produces, related to complementary systems. 3. In the embryonic period, the liver is associated with immune associated cell growth and their maturation. After birth, it is associated with removing old red blood cells and with systematically modulating immune system through hormone metabolism. 4. The liver controls the autoimmune disease resulting from immune complex by removing molecules like immune complex. 5. In the processing of blood 19A from the digestive system, the liver has an important role in protecting the body from unnecessary immune responses. 6. In the oriental medical view, liver plays a major role in the immune function by storing blood and dispersing stagnated hepatoqi with the help of the kidneys and spleen.

• Journal of Pharmaceutical Investigation
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• v.37 no.2
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• pp.95-99
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• 2007

To develop topical nitroglycerin (NTG) preparation far chronic anal fissure treatment, the release rate of NTG should be controlled carefully. For this, microemulsion was prepared from the phase diagram construction with Cremophor ELP, ethanol and Labrafil $M1944CS^{(R)}$ and the topical gel was prepared by dispersing NTG containing microemulsion into hydrophilic polymers. in viかo release characteristics were evaluated with Franz diffusion cell using cellulose membrane and compared with control hydrogels. The release rate of NTG was followed $1^{st}$ order kinetics and, when comparing the NTG release from control hydrogel with that from the microemulsion-based hydrogel, the NTG release rate was controlled by the content of polymers within continuous phase and the concentration of dispersed phase.

• Industrial Engineering and Management Systems
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• v.4 no.2
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• pp.198-206
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• 2005

The single sourcing policy, in which an automobile manufacturer purchases identical or similar parts from one supplier, has an advantage of scale economy. Meanwhile, multiple sourcing policy, which allows procuring similar parts from multiple suppliers, has benefits of dispersing risks and promoting competition among suppliers. This paper analyzes the procurement policies by presenting a model of the Japanese automobile parts trade. It concludes that maturity of technology involved should be taken into account besides above-mentioned factors which have traditionally been recognized. For parts produced using evolving technologies, the single sourcing enhances purchaser’s benefits because of the scale economy in learning process. In the meantime, multiple sourcing is more beneficial to the purchaser if the parts are based on mature technologies. In either policy, if the technology involved is evolving, motivating suppliers by returning a great part of cost reduction as a reward to them may eventually increase profit for the purchaser. The conclusion supports the situation where the number of suppliers is being cut down as the trend of modularization and system deliveries of parts progresses in the auto parts industry, and suggests that returning part of benefits to parts suppliers may be encouraged from the viewpoint of auto manufacturers’ own interest.

• Journal of Powder Materials
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• v.12 no.4 s.51
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• pp.249-254
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• 2005

Titanium dioxide was prepared by Polymer Complex Solution Method(PCSM) according to the mole ratio of Titanium (IV) isopropoxide(TTIP)/solvent and polymer(Poly Ethylene Glycol). Polymer electrolytes were usually made by dispersing preproduced ceramic nanoparticles in a polymer matrix. Using this method, pure and nano-sized $TiO_2$ powder was synthesized through a simple procedure and polymer entrapment route. At the optimum amount of the polymer, the titanium ions are dispersed in solution and a homogeneous polymeric network is formed. The maximum intensity of anatase phase of $TiO_2$ was achieved by calcining at $500^{\circ}C$ for 2h. The synthesized $TiO_2$ powders were nano-sized and the average size was about 50nm. Anatase/Rutile ratio of the synthesized $TiO_2$ was 70%/30%.

• Journal of the Korean Applied Science and Technology
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• v.21 no.1
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• pp.62-68
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• 2004

PU flame-retardant coatings (APHD) containing phosphorous were prepared by blending of hexamethylene diisocyanate-trimer, white pigment, dispersing agent, flowing agent, and previously prepared benzoic acid modified polyester (APTB) that contains phosphorous. Physical properties of the prepared APHD were examined. With the introduction of BZA (contained in APTB), the film viscosity and film hardness of APHD decreased. With the introduction of caprolactone group, the flexibility, impact resistance, accelerated weathering resistance of APTBs increased. Flame retardancy of the coatings was tested. In a vertical burning method, APHD shows 210${\sim}$313 seconds, and in a $45^{\circ}$ Meckel burner method, shows 1.3${\sim}$4.0$cm^2$ of char length, which indicates that the coatings are good flame-retardant coatings. Moreover, the amount of afterglow and flame retardancy of the coatings are decreased with increasing BZA content.