• Journal of rehabilitation welfare engineering & assistive technology
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• v.3 no.1
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• pp.27-34
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• 2009

Hearing impaired person's hearing loss has personally various shape, so existing symmetrical auditory filter of frequency band method wasn't properly simulated the hearing impaired person's various hearing loss shape. The shapes of auditory filter are asymmetrical different with each center frequency and each input level. Hearing impaired person which has hearing loss was differently changed with that of normal hearing people and it has different value for speech of quality through auditory filter. In this study, the asymmetrical auditory filter was simulated and then some tests to estimate the filter's performance objectively were performed. The experiment as simulated auditory filter's performance evaluation method used perceptual evaluation of speech quality (PESQ) and log likelihood ratio (LLR) for speech through auditory filter. In the test, processed speech was evaluated objective speech quality and distortion using PESQ and LLR value. When hearing loss processed, PESQ and LLR value have big difference between symmetrical and asymmetrical auditory filter. It means that the difference of the shape auditory filter may affect to speech quality. Especially, when hearing loss existed, auditory filter changing according to asymmetrical shape for each center frequency affected to perceive speech quality of the hearing impaired.

• Spatial Information Research
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• v.14 no.4 s.39
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• pp.363-377
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• 2006

Mean annual soil loss was calculated and critical soil erosion areas were identified for the Congaree River Basin in South Carolina, USA using the Revised Universal Soil Loss Equation (RUSLE) model. In the RUSLE model, the mean annual soil loss (A) can be calculated by multiplying rainfall-runoff erosivity (R), soil erodibility (K), slope length and steepness (LS), crop-management (C), and support practice (P) factors. The critical soil erosion areas can be identified as the areas with soil loss amounts (A) greater than the soil loss tolerance (T) factor More than 10% of the total area was identified as a critical soil erosion area. Among seven subwatersheds within the Congaree River Basin, the urban areas of the Congaree Creek and the Gills Creek subwatersheds as well as the agricultural area of the Cedar Creek subwatershed appeared to be exposed to the risk of severe soil loss. As a prototype model for examining future effect of human and/or nature-induced changes on soil erosion, the RUSLE model customized for the area was embedded into ESRI ArcGIS ArcMap 9.0 using Visual Basic for Applications. Using the embedded model, users can modify C, LS, and P-factor values for each subwatershed by changing conditions such as land cover, canopy type, ground cover type, slope, type of agriculture, and agricultural practice types. The result mean annual soil loss and critical soil erosion areas can be compared to the ones with existing conditions and used for further soil loss management for the area.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.2
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• pp.40-49
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• 2003

Ferrule is widely used as fiber optic connecters. In fiber-optic communications. the shape accuracy such as coaxiality and cylindricity of ferrule affects insertion loss. When coaxial grinding of ferrule supported by two pin. pin alignment and chucking accuracy are very important. In this research, the kinematic behavior of the ferrule centers are investigated in the case where the ferrule is chucked with the cone-shaped center pins and bail centers, With homogeneous coordinate transformation and numerical analysis, the obtained results are as follows: In the case of cone-type center, the alignment errors between center pins alone do not affect the rotation accuracy of ferrule. The alignment errors between center holes cause sinusoidal displacement of ferrule. And the maximum displacement of ferrule centers is proportional to the center pin angle. In the case of ball-type center, the displacements of ferrule centers has similar pattern as cone-type center, and the alignment errors art proportional to ball diameters.

• Korea Journal of Cosmetic Science
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• v.1 no.1
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• pp.11-18
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• 2019

Caffeine is widely used in cosmetics and hair care products. Although its efficacy in stimulating hair growth has been confirmed in recent studies, its mechanism of action remains unelucidated. The present study aimed to determine the effects of caffeine on hair growth, with a focus on intracellular hair follicle activity. Experiments included in vitro and ex vivo tests, and a clinical study. Caffeine enhanced the cellular activity and potassium channel opening. It also promoted human hair follicle elongation. Immunohistochemical staining showed that the Ki-67 signal was significantly higher in cells treated with caffeine. These efficacies of caffeine were comprehensively demonstrated in clinical results, wherein caffeine-containing shampoo improved hair density after 24 weeks of testing. Collectively, the results of this study demonstrated that caffeine promoted hair growth and inhibited the progression of hair loss by enhancing intracellular activity of hair follicles.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.8 s.99
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• pp.790-796
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• 2005

In order to accomplish a wireless communication of capsule endoscopy, an environment study in the human body and receiving antenna design have been performed. The proposed antenna is the loop antenna designed to minimize the propagation loss in multi-loss layer such as the human body and utilize the magnetic field. Considering the propagation loss in the human body, the frequency range is from 400 MHz to 500 MHz. Acorrrding to the FCC regulations, the permittivity and conductivity for each human tissue were extracted. We set up an equivalent model and make an aqueous solution which is replaced with the human body. Due to movement of capsule in the human body which propagation loss is extremly severe, an array antenna is required. Irrespective of the location of transmission antenna transmitting a signal of 1 mW, we confirme what it is possible for the enough signal detection as the average signal level of array antenna is -60 dBm.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.9 s.240
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• pp.988-996
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• 2005

Flame structure and extinction mechanism of counterflow methane/air non-premixed flame diluted with nitrogen are studied by NASA 2.2 s drop tower experiments and two-dimensional numerical simulations with finite rate chemistry and transport properties. Extinction mechanism at low strain rate is examined through the comparison among results of microgravity experiment, 1D and 2D simulations with a finite burner diameter. A two-dimensional simulation in counterflow flame especially with a finite burner diameter is shown to be very important in explaining the importance of multidimensional effects and lateral heat loss in flame extinction, effects that cannot be understood using a one-dimensional flamelet model. Extinction mechanism at low strain rate is quite different from that at high strain rate. Low strain rate flame is extinguished initially at the outer flame edge, the flame shrinks inward, and finally is extinguished at the center. It is clarified from the overall fractional contribution by each term in energy equation to heat release rate that the contribution of radiation fraction with 1D and 2D simulations does not change so much and the overall fractional contribution is decisively attributed to radial conduction ('lateral heat loss'). The experiments by Maruta et at. can be only completely understood if multi-dimensional heat loss effects are considered. It is, as a result, verified that the turning point, which is caused only by pure radiation heat loss, has to be shifted towards much lower global strain rate in microgravity flame.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.3
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• pp.1605-1610
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• 2015

The present study has been accomplished to elucidate the effect of radiation heat transfer in the heat transfer analysis of refrigerator gasket, which has near 30% of refrigerator heat loss. The numerical heat transfer analysis has been conducted with the simplified modeling of refrigerator gasket. From the present CFD analysis, heat loss at the gasket is $25.6W/m^2$ for the case without radiation effect and that for the case with radiation effect is $55.0W/m^2$, which is 2.2 times greater heat loss. The radiation protection layers were installed in the gasket from 0 to 7 and the case with 7 layers has 33% reduction effect of heat loss compared with the case without any radiation protection layer. Additionally, it is better effect of radiation heat loss reduction that the radiation protection layers would be placed to the outer or inner side of gasket rather than placing to the center of gasket.

• Journal of Animal Science and Technology
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• v.58 no.7
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• pp.27.1-27.8
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• 2016

Background: Studies on prevalence of pale, soft, exudative (PSE) condition in Sri Lankan poultry industry is minimal. Hence, the objective of present study was to determine the incidence of PSE chicken meat in a commercial meat processing plant and to find out its consequences on meat quality traits of roasted chicken breast. Method: A total of 60 breast fillets were randomly selected, evaluated based on color L* value, and placed into 1 of 2 categories; PSE (L* > 58) or normal meat ($L*{\leq}58$). A total of 20 breast fillets (10 PSE and 10 normal) were then analyzed for color, pH, and water holding capacity (WHC). After processing those into roasted chicken breast, cooking loss, color, pH, WHC, and texture values were evaluated. A sensory evaluation was conducted using 30 untrained panelists. Results: The incidence of PSE meat was 70 % in the present experiment. PSE fillets were significantly lighter and had lower pH values compared with normal fillets. Correlation between the lightness and pH was negative (P < 0.05). Although there was no significant difference in color, texture, and WHC values between the 2 groups after processing into roasted chicken breast (P > 0.05), an approximately 3 % higher cooking loss was observed in PSE group compared to its counterpart (P < 0.05). Moreover, cooking loss and lightness values showed a significant positive correlation. Nevertheless, there were no significant differences in sensory parameters between the 2 products (P > 0.05). Conclusions: These results indicated that an economical loss can be expected due to the significantly higher cooking loss observed in roasted breast processed from PSE meat.

• The korean journal of orthodontics
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• v.46 no.5
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• pp.310-322
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• 2016

Objective: The aim of this study was to determine the optimal loading conditions for pure intrusion of the six maxillary anterior teeth with miniscrews according to alveolar bone loss. Methods: A three-dimensional finite element model was created for a segment of the six anterior teeth, and the positions of the miniscrews and hooks were varied after setting the alveolar bone loss to 0, 2, or 4 mm. Under 100 g of intrusive force, initial displacement of the individual teeth in three directions and the degree of labial tilting were measured. Results: The degree of labial tilting increased with reduced alveolar bone height under the same load. When a miniscrew was inserted between the two central incisors, the amounts of medial-lateral and anterior-posterior displacement of the central incisor were significantly greater than in the other conditions. When the miniscrews were inserted distally to the canines and an intrusion force was applied distal to the lateral incisors, the degree of labial tilting and the amounts of displacement of the six anterior teeth were the lowest, and the maximum von Mises stress was distributed evenly across all the teeth, regardless of the bone loss. Conclusions: Initial tooth displacement similar to pure intrusion of the six maxillary anterior teeth was induced when miniscrews were inserted distal to the maxillary canines and an intrusion force was applied distal to the lateral incisors. In this condition, the maximum von Mises stresses were relatively evenly distributed across all the teeth, regardless of the bone loss.

• Journal of the Korean Society for Railway
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• v.19 no.4
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• pp.468-479
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• 2016

In order to supply power to online monitoring systems that are attached to high voltage catenary or overhead wires, a wireless power transfer system is required that is able to transmit power over the insulation gap. Such wireless power transfer systems have transmitter and receiver coils that have diameters of over 10cm. This paper focused on an investigation of the sources of loss in the coils when the coils are fabricated using printed circuit board technology. Using finite element simulation results, it has been shown that the dielectric loss in the substrate was the dominant source of the total loss. It has been demonstrated that the selection of a proper dielectric material was the most critical factor in reducing the loss. For further reduction of the loss, the distributed tuning capacitor method and the slotting of the inter-turn spaces have been proposed. For the evaluation of the proposed methods, four coils have been fabricated and their equivalent series resistances and quality factors were measured. Measured quality factors were greater than 300, which means that these devices will be helpful in achieving high coil-to-coil efficiency.