• Journal of the Korean Geosynthetics Society
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• v.13 no.1
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• pp.53-61
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• 2014

Sea gives us a lot of benefits and one of them is a role of transporting goods easily by ship. Accordingly the industrial area or the container yard is constructed either on the low sea or near the sea. Sea dredging ground is made by pumping them using dredge pump to the inside of embankment after dredging undersea soils. The dredging ground after pumping is in the slurry state but as time goes, consolidation by the own weight happens and evaporation happens at the surface of dredging ground. The evaporation causes the crest layer in the upper side of dredging ground. Under the crest layer there is still a soil of slurry state which has just little bearing resistance. This kind of characteristics makes it difficult to get a exact bearing capacity using the equations proposed until now. In this study we have performed simultaneously both the field loading tests and the cone penetration tests on the sea dredging ground. From the result of field tests, new experimental equation for the ultimate bearing capacity has been proposed. If we use the new equation, it is believed that some design of sea dredging ground could be more accurate.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.12
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• pp.34-40
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• 2016

In ventilated seats for cars, air flow is generated by a fan and passed through a foam pad, foam filter, and seat cover. There is a significant loss of air flow in this process, and it is not easy to analyze the amount delivered to the driver. Another difficulty is the geometric complexity of the air flow passage inside the seats. In this paper, the air flow through a foam pad was analyzed. Proper modeling of the bumps in the ventilation mat was found to be important in the analysis. Air flow is lost when it passes through the porous pad foam, which was measured and used to correct the analysis results. The corrected analysis results were in a good agreement with the experimental results. The amount of air flow delivered to a driver was measured using an airflow cone. Only 35.7% of the air flow from the fan was delivered.

• The korean journal of orthodontics
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• v.50 no.5
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• pp.346-355
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• 2020

The treatment of skeletal Class III malocclusion in adolescents is challenging. Maxillary protraction, particularly that using bone anchorage, has been proven to be an effective method for the stimulation of maxillary growth. However, the conventional procedure, which involves the surgical implantation of mini-plates, is traumatic and associated with a high risk. Three-dimensional (3D) digital technology offers the possibility of individualized treatment. Customized mini-plates can be designed according to the shape of the maxillary surface and the positions of the roots on cone-beam computed tomography scans; this reduces both the surgical risk and patient trauma. Here we report a case involving a 12-year-old adolescent girl with skeletal Class III malocclusion and midface deficiency that was treated in two phases. In phase 1, rapid maxillary expansion and protraction were performed using 3D-printed mini-plates for anchorage. The mini-plates exhibited better adaptation to the bone contour, and titanium screw implantation was safer because of the customized design. The orthopedic force applied to each mini-plate was approximately 400-500 g, and the plates remained stable during the maxillary protraction process, which exhibited efficacious orthopedic effects and significantly improved the facial profile and esthetics. In phase 2, fixed appliances were used for alignment and leveling of the maxillary and mandibular dentitions. The complete two-phase treatment lasted for 24 months. After 48 months of retention, the treatment outcomes remained stable.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.25 no.4 s.34
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• pp.123-131
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• 1999

Liquid crystal known as a rheological barrier to coalescence of oil droplets, increases emulsion stability, water-holding capacity and promotes active material penetration to skin. Some investigation for its rheological characteristics have been reported but its relations to consumer perception have been rarely published. In this study, oil/water emulsion and oil/liquid crystal/water systems were manufactured using the same composition or Behenyltrimethylammonium chloride/Cetostearyl alcohol/Lanolin oil. and rheological properties or each system were investigated with Cone and Plate rheometer. The formation of liquid crystalline phase was observed with polarized microscope and Differential Scanning Calorimeter. Continuous shear experiment, creep, yield and water holding capacity were measured for oil/water and oil/liquid crystal/water systems. The results were compared with sensory evaluations. Oil/liquid crystal/water system showed higher,viscosity at the same shear rate. higher viscoelasticity and higher yield stress than oil/water system. These properties were expected to show good spreadability and excellent richness without waxiness in hair can: products of creme type. This expectation was consistent with the results of sensory experiments. Water-holding capacity was evaluated by measuring residual water of specimens at specific temperature and relative humidity. Oil/liquid crystal/water system was proved to have higher ability to hold water in comparison with oil/water system. The results indicated that oil/liquid crystal/water system was of benefit to rheological properties creme type hair care products.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.4
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• pp.487-493
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• 1995

This study was carried out to select useful chemicals to control pathogens inciting soybean-sprout rot. Pathogen strains were isolated from decaying soybean seedlings. The isolated strains were identified as Pseudomonas spp. (Pse. strains) through microbiological test, however, no rot-inciting fungus was isolated. Eight food additives were tested with different concentrations in controlling pathogens and harmfulness. Five chemicals(over 5% cone.) including sodium hypochlorite apparently inhibited the growth of Pse. strains on media plate, however, sodium hypochlorite was discarded due to its severe germination inhibition. Propionic acid and acetic acid inhibited the growth of Pse. strains more effectively than calcium propionate and sodium propionate relatively. As no harmful effect on seed germination and no growth retard of soybean sprouts were observed by those chemicals with lower concentration(0.5∼1.0%), these chemicals were considered to be applicable to sprout rot control judged by the effectiveness and permissible concentration as food additives.

• Journal of Oral Medicine and Pain
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• v.39 no.3
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• pp.90-95
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• 2014

Purpose: To investigate viscosity and wettability of hyaluronic acid (HA) solutions according to supplementation of lysozyme and/or peroxidase, and different ionic strength and pH conditions. Methods: Solutions containing HA were prepared using distilled deionized water (DDW) and simulated salivary buffer (SSB) in different conditions. Different concentrations of hen egg-white lysozyme and bovine lactoperoxidase was added into HA solutions. HA solutions with antimicrobials in different ionic strength and pH conditions were prepared. Viscosity was measured using cone-and-plate digital viscometer at six different shear rates and wettability on acrylic resin and Co-Cr alloy was determined by contact angle. Results: The viscosity values of HA dissolved in DDW were decreased in order of HA, HA containing lysozyme, HA containing peroxidase, and HA containing lysozyme and peroxidase. The viscosity values for HA in DDW were decreased as the concentration of lysozyme and/or peroxidase increased. However, the viscosity values for HA in SSB showed no significant changes according to the concentration of lysozyme and/or peroxidase. The viscosity values of HA solutions were inversely proportional to ionic strength and pH. The contact angle of HA solutions showed no significant differences according to tested surface materials, addition of lysozyme and/or peroxidase, and different ionic strength and pH conditions. Contact angles on acrylic resin by HA solutions in all tested conditions were much higher than those by human saliva. Conclusions: The rheological properties of HA supplemented with lysozyme and/or peroxidase in different ionic strength and pH conditions were objectively confirmed, indicating the possibility of HA with lysozyme and/or peroxidase as main components in the development of effective saliva substitutes.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.9
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• pp.1299-1308
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• 2003

This paper is studied to investigate the effect of slits and swirl vanes on the development of turbulent flow fields in gun-type gas burner with a cone type baffle plate because this gas burner is generally composed of eight slits and swirl vanes. All of turbulent characteristics including mean velocities were measured in the horizontal plane and cross section by using X-type hot-wire probe from hot-wire anemometer system. This experiment is carried out at flow rate 450 l/min in the test section of subsonic wind tunnel. Slits cause the fast jets, and then they have the characteristic that the flow is not adequately spread to radial direction and has long flow length and very small flow velocity distribution in the central part. On the contrary, swirl vanes does not have long enough for adequate flow length to downstream because the rotational flow diffuses remarkably to radial direction. However, the suitable arrangement between slits and swirl vanes causes effective flow width and flow length, and then it promotes fast flow mixing over the entire region including central part to increase turbulence more largely and effectively. Therefore, it is thought as a very desirable design method in gun-type gas burner to locate slits on the outside of swirl vanes.

• International Journal of Highway Engineering
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• v.14 no.3
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• pp.49-58
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• 2012

In many countries including Korea, the design concept of pavement structure has been converted from empirical method to mechanisticempirical method since the advent of compaction control based on resilient modulus proposed by AASHTO in 1986. Studies of last decades indicates that the classical compaction control method based on relative compaction and plate bearing test(PBT) will necessarily move to the methods taking advantage of light falling weight deflectometer(LFWD) and dynamic cone penetrometer(DCP) in addition to PBT. In this study, the validity of resilient modulus prediction equation proposed by Korean Pavement Design Guide is verified by comparison with physical properties of subgrade soil and the results of structural analysis. In addition, correlational equations between elastic modulus measured by various field tests and resilient modulus estimated by empirical model are proposed. Finally, a field test-based compaction control procedure for subgrade is suggested by using proposed correlational equations.

• The Journal of the Korean Society for Microbiology
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• v.22 no.4
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• pp.435-443
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• 1987

A total of 30 strains of Candida albicans were examined for susceptibility to amphotericin B and ketoconazole using Sabouraud's dextrose broth, Kimmig broth and Supplemented yeast nitrogen base broth media. Furthermore, the growth curve and colony forming units were checked for use of stationary-phase cells and 2-hour incubation cells in the absence of atifungal agents. The viable counts were determined periodically during incubation by standard plate count techniques. The minimum inhibitory concentrations of amphotericin B for use of stationary phase cells were as follows: SDB, $0.09{\sim}0.97mcg/ml$(0.39mcg/ml); Kimmig broth, $0.19{\sim}0.39mcg/ml$(0.42 mcg/ml) and SYNB, $0.19{\sim}0.39mcg/ml$mcg/ml(0.23mcg/ml). In ketoconazole, MICs were value SDB, $3.12{\sim}25.0mcg/ml$(12.5mcg/ml); Kimmig broth, $12.5{\sim}25.0mcg/ml$ (22.5mcg/ml) and SYNB, $3.12{\sim}12.5mcg/ml$(6.71mcg/ml). The MICs of amphotericin B(0.2mcg/ml cone.) for use of 2-hour incubation cells in absence of AMB were, SDB, $0.04{\sim}0.39mcg/ml$(0.11mcg/ml); Kimmig broth, $0.09{\sim}0.39mcg/ml$(0.18mcg/ml) and SYNB, $0.09{\sim}0.19mcg/ml$(0.14mcg/ml) and in KTZ, the value of MICs were SDB, $3.12{\sim}25.0mcg/ml$(12.22mcg/ml); Kimmig broth, $0.78{\sim}25.0mcg/ml$(11.01mcg/ml) and SYNB, $1.56{\sim}12.5mcg/ml$(3.90mcg/ml). The two-log reductions in CFU per milliliter observed when 2 hour preincubation cells were treated with 0.2mcg/concentrations of AMB and 25.0mcg/ml of KTZ. However, AMB treated cells were restored to growth activity, it suggested that the AMB has no active antifungal activity.

• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.221-225
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• 2001

Flow properties of red flower cabbage pigment solutions were determined over a wide range of temperatures ($20-50^{\circ}C$) and soluble solid concentrations (1-65%) using a cone and plate rotational viscometer. Flow properties of the pigment solutions were adequately described by the simple power law model. Within the tested ranges of concentration, temperature and shear rate, the flow behavior index (n) and the consistency index (K) of the solutions were in the ranges of 0.841-0.998 and $0.008-31.525\;Pa{\cdot}s^n$, respectively. The effect of temperature on the apparent viscosity of the solutions followed an Arrhenius type relationship. Activation energy of flow varied from 9.36 to 52.48 kJ/mol depending on the solid concentration and shear rate. The combined effect of temperature and concentration on the apparent viscosity at the shear rate of $100\;s^{-1}$ could be represented by a single equation as ${\ln}\;{\eta}_a\;=\;6.11\;-\;3103.94(1/T)\;-\;0.03C$.