• Journal of the korean academy of Pediatric Dentistry
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• v.42 no.1
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• pp.45-52
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• 2015

The purpose of this study was to compare and evaluate facemask effects when two types of intraoral appliances were used for maxillary protraction for patients with class III malocclusion. Eighteen patients with class III malocclusion were treated with a facemask for an average of 12 months. Two types of intraoral appliances were used: nine patients were treated with bonded expander (Group 1), and nine patients with Hyrax (Group 2). Cephalometric radiographs were taken before and after treatment. Cephalometric radiographs were traced, analyzed, and the results such as sagittal, vertical and soft-tissue changes were compared between two groups. The amount of anchorage loss was also measured to evaluate the difference between two groups. All patients showed significant sagittal skeletal changes after treatment, and there was no statistically significant difference between the two groups. When anchorage loss was evaluated, no differences were shown between the two. Facemask with Hyrax or bonded expander is similarly an effective method as a treatment in class III malocclusion patients.

• Korean Journal of Biological Psychiatry
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• v.6 no.1
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• pp.12-20
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• 1999

In order to understand the pathogenesis and progression of some synaptic loss related neuropsychiatric diseases, We attempted to develop a computer model in this study. We made a simple autoassociative memory network remembering numbers, transformed it into a disease model by pruning synapses, and measured its memory performance as a function of synaptic deletion. Decline in performance was measured as amount of synaptic loss increases and its mode of decline is sudden or gradual according to the mode of synaptic pruning. The developed computer model demonstrated how synaptic loss could cause memory impairment through a series of computer simulations, and suggested a new way of research in neuropsychiatry.

• Korean Journal of Materials Research
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• v.20 no.9
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• pp.467-471
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• 2010

Composites of ceramic powders and an elastomer-based matrix were prepared by mixing $CaCO_3$ powders with polyethylene and polypropylene elastomers, and their mechanical and sound insulation properties were measured. $CaCO_3$ powders with 0.7 ${\mu}m$ and 35 ${\mu}m$ particle size were added to elastomers up to 80 wt%. Scanning electron microscopy photographs showed uniform distribution of the $CaCO_3$ powders in the matrix. While density and surface hardness increased, melt index, tensile strength and elongation of the composites decreased as the amount of added $CaCO_3$ powders increased. As more $CaCO_3$ powders were added sound transmission loss of the composites increased owing to the increase of density. Addition of 0.7 ${\mu}m$ sized $CaCO_3$ powders resulted in a slightly higher transmission loss than the addition of 35 ${\mu}m$ sized powders because of the increased interface area between the elastomer matrix and the $CaCO_3$ powders. Composites with a polyethylene matrix showed higher transmission loss than those with a polypropylene matrix because the tensile strength and hardness of the polyethylene-based composites were low and their elongation was high.

• Journal of Korea Water Resources Association
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• v.34 no.5
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• pp.459-472
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• 2001

The objective of this study is to evaluate the filtration efficiency of deep-bed filters by comparing to single and dual media filters. Pilot-plant tests using four-filter columns were conducted for the comparison of head loss development and filtered water quality. The dual-media filter showed greater initial head loss, but less rate of head-loss development than those of the coarse-sand-0deep-bed filters. For 180 m/day of filtration rate, the dual-media filter produces larger unit production rate by 30-40%, and the turbidities of filtered water were below 0.1 NTU. The initial breakthrough could be effectively controlled by the dual-media filter rather than coarse-sand-deep-bed filters.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.12
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• pp.1585-1590
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• 2012

Engineering plastics are used in instrument panels, interior trim, and other vehicle applications, and the thermomechanical behaviors of plastic materials are strongly influenced by many environmental factors such as temperature, sunlight, and rain. As the material properties change, the mechanical parts create unexpected noise. In this study, the dynamic mechanical property changes of plastics used in automobiles are measured to investigate the temperature effects. Viscoelastic properties such as the glass transition temperature and storage modulus and loss factor under temperature and frequency sweeps were measured. The data were compared with the original ones before aging to analyze the behavior changes. It was found that as the temperature increased, the storage modulus decreased and the loss factor increased slightly.

• Food Science of Animal Resources
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• v.28 no.5
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• pp.567-573
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• 2008

This study investigated the effects of sodium chloride, potassium chloride, potassium lactate and calcium ascorbate on the physico-chemical and sensory characteristics of sodium-reduced pork patties. Pork patties were prepared in 4 ways: T1 (control, 1.0% NaCl), T2 (0.6% NaCl, 0.4% KCl), T3 (0.7% NaCl, 0.3% potassium lactate) and T4 (0.7% NaCl, 0.3% calcium ascorbate). The pH, cooking loss, total plate counts, TBARS (2-thiobarbituric acid reactive substances), surface color (L, a, b) and sensory characteristics were evaluated. The partial substitution of NaCl with KCl and calcium ascorbate decreased the cooking loss and TBARS values, and enhanced microbial stability. The partial substitution of NaCl with potassium lactate significantly decreased TBARS values and enhanced microbial stability, but significantly increased cooking loss compared to the control after 1 and 4 days of storage. However, the surface color and sensory characteristics were not affected by any of the treatments.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.3 s.118
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• pp.257-264
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• 2007

In this paper, we have designed and fabricated a wide-band and high gain antenna which can integrate a standard of IEEE 802.1la$(5.15\sim5.25\;GHz,\;5.25\sim5.35\;GHz,\;5.725\sim5.825\;GHz)$. We inserted a parallel dual slot into a rectangular patch to have wide-band, and we offset an element of capacitance from the slot by using coaxial probe feeding method. We also designed a converter of $\lambda_g/4$ impedance with taper type line so that wide-band impedance can be matched easily. We finally designed structure with $2\times2$ array in order to improve the antenna gain, and the final fabricated antenna could have a good return loss(Return loss$\leq$-10 dB) and a high gain(over 13 dBi) at the range of $5.01\sim5.95\;GHz(B/W\doteqdot940\;MHz)$.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.36 no.4
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• pp.241-251
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• 2010

In recent years, the number of people suffering from depression due to hair loss has been increasing. The treatment methods such as clinical pathology and vanity surgery have been developed. There are therapies and materials for hair growth promotion and hair loss prevention. But the effectiveness of such therapies and materials is not fully evaluated and some side-effects have been reported. In this study, microneedle therapy using very thin and delicate needles promotes absorption of drug. During this therapy, the microneedle makes micro holes that help absorbion of drugs into the scalp. In this study, absorbion of fermented soybean were evaluated. The ingredient has antioxidant, antiandrogen, and antithrombosis effect for alopecia. The fermented soybean is more effective for complex hair loss when used with microneedle. It is because of the microneedle's excellent drug delivery system (DDS). This therapy that increases the absorption of fermented soybean is a very useful scalp care method which prevents, treats and controls alopecia. This microneedle therapy using fermented soybean is an advanced technology for scalp care.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.54-61
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• 1999

A study was conducted to find a rapid thawing method which prevents excessive drip loss and local overheating. Effects of thawing methods (conventional thawing vs. 2,450 and 915 MHz microwave thawing) on thawing time, temperature profile, drip loss, water holding capacity, total color difference and total aerobes were investigated. Samples were thawed at 4, 28 and $50^{\circ}C$ in a refrigerator or an oven for the conventional thawing methods the convertional thawing methods. Power levels of 5, 10 and 15 kW were used for 915MHz microwave thawing. Cotreatment of 915 MHz microwave and convectional heating $(120^{\circ}C)$ was tested. 915 MHz microwave accelerated the thawing rate, and showed significant effects on penetration depth, drip loss, water holding capacity and total aerobes. Cotreatment of 915 MHz microwave and convection heating was appeared to be a suitable thawing process for the food industry.

• Korean Journal of Medicinal Crop Science
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• v.20 no.2
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• pp.108-116
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• 2012

In this study, to develop hair growth agents using natural products which has excellent ability to promote hair growth effect and fewer side effect, animal experiment and clinical trials was performed to evaluate hair growth promotion effect of herbal product containing $Rosa$ $mutiflora$ roots extracts as a main component (RMHP). 4-week-old male C57BL/6 mice were removed the dorsal hair using thioglycolate, and applied 15% EtOH solution as a negative control, 5% minoxidil as a positive control and RMHP to dorsal skin. In the results of macroscopy and photo-interpretation, RMHP group recorded 100% (+++++) of hair growth was proved to significantly stimulate hair growth against 80% (++++) negative control group. 37 patients were treated with RMHP and evaluated the therapeutic effect at 16 weeks. Hair density was significantly increased at 16 weeks after applying RMHP ($125.0{\pm}4.9\;FU/cm^2$) compared to before treatment ($104.3{\pm}4.7\;FU/cm^2$, p < 0.05), and hair thickness were also significantly increased ($0.066{\pm}0.003$ mm) than before treatment ($0.055{\pm}0.002$ mm, p < 0.05). The result of clinical photo-interpretation using 7-point rating scale assessment, after 16 weeks clinical symptoms were evaluated to significantly improve with $1.23{\pm}0.05$ (p < 0.05). Therefore, the results of this study were observed that RMHP have hair loss prevention effect and hair growth promotion effect to hair loss patients.