• Journal of Korean Society for Atmospheric Environment
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• v.11 no.E
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• pp.1-12
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• 1995

In recent years the demand for energy conservation has resulted in "tight" buildings with decreased air change rates. Although a reduction in air change rates can save energy utilized for heating or cooling of dwellings, there is an increased concern for the air quality of the indoor environment where individuals spend most of their lifetime (Schwab et al., 1990).., 1990).

• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.04a
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• pp.53-56
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• 2003

The objective of this research is to investigate the thermal behavior of microencapsulated phase-change materials(MEPCM), and a shell of melamine-formaldehyde. These PCM materials were tested using DSC and thermal data station. Fabrics with enhanced thermal properties were prepared by padding the fabrics with the microcapsules containing PCM and acryl binder. The rate of temperature increase was significantly decreased as the amount of MEPCM added on the surface of the fabrics increased.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.874-877
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• 2002

The optogalvanic signals were measured using hollow cathode discharge tube with argon as buffer gas at change of discharge currents. A change of ionization rate due to electron collision causes an increase or decrease of the electric conductivity. This change in electric conductivity generates the optogalvanic signal. We conclude that optogalvanic signal has close relation with the lowest metastable atoms density at low current.

• Journal of the Korean Data and Information Science Society
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• v.15 no.2
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• pp.387-394
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• 2004

Zero-Inflated Poisson distribution is Poisson distribution with excess zeros. Recently defects of product hardley happen in the manufacturing process. In this case it is desirable to apply to the Zero-Inflated Poisson distribution rather than Poisson. Our target of this paper is to study the tests for changes of rate of defects after the unknown change-point. We are going to compare the powers of the two proposed tests with likelihood tests by the simulations.

• Korean Journal of Plant Resources
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• v.33 no.2
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• pp.106-115
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• 2020

In order to find out the relationship between spring phytophenological index and temperature index for the past nine years (2010~2018), this study identified the relationship between temperature changes and trends in spring phytophenological index of sprouting, flowering and leaf unfolding of Pinus densiflora Siebold & Zucc., Larix kaempferi (Lamb.) Carrière, Quercus mongolica Fisch. ex Ledeb., Rhododendron mucronulatum Turcz., Lindera obtusiloba Blume and Acer pseudosieboldianum (Pax) Kom. in Daegu Arboretum, Palgong mt., Juwang mt. and Gaya mt. The change in temperature was caused by an increase in the monthly average temperature between March and April compared to February for nine years, and the average temperature of Daegu Arboretum and Palgong mt. were higher by region. The sprouting, flowering and leaf unfolding were the fastest of the Lindera obtusiloba and the slowest of the Pinus densiflora for each species, and the fastest plant season in Daegu arboretum came. SPI (Spring Phytophenological Index) tends to advance by -1.267~-6.151/9 years, with the largest Pinus densiflora (-6.151/9 years), with the lowest rate of change for Rhododendron mucronulatum (-1.267 days/9 years). Species which shows significant values in sprouting, flowering and leaf unfolding is Rhododendron mucronulatum and Pinus densiflora, which correlate with the mean temperature of January to March. As a result of checking the time series change of SPI, the change rate in the four regions was all negative and the phenolocal index was all accelerating. Among them, the rate of change was greater in inland areas such as Daegu arboretum, Palgong Mt. and Gaya mt. and the rate of change was slightly lower in the case of Juwang mt., which is somewhat distant.

• Journal of Convergence Society for SMB
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• v.6 no.4
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• pp.71-77
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• 2016

In this paper, we proposed a verification of speaker change utilizing the KL distance based on GMM-UBM to improve the performance of conventional BIC based Speaker Change Detection(SCD). We have verified Conventional BIC-based SCD using KL-distance based SCD which is robust against difference of information volume than BIC-based SCD. And we have applied GMM-UBM to compensate asymmetric information volume. Conventional BIC-based SCD was composed of two steps. Step 1, to detect the Speaker Change Candidate Point(SCCP). SCCP is positive local maximum point of dissimilarity d. Step 2, to determine the Speaker Change Point(SCP). If ${\Delta}BIC$ of SCCP is positive, it decides to SCP. We examined verification of SCP using GMM-UBM based KL distance D. If the value of D on each SCP is higher than threshold, we accepted that point to the final SCP. In the experimental condition MDR(Missed Detection Rate) is 0, FAR(False Alarm Rate) when the threshold value of 0.028 has been improved to 60.7%.

• Journal of Obesity & Metabolic Syndrome
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• v.27 no.4
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• pp.203-212
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• 2018

Dynamic energy balance can give clinicians important answers for why obesity is so resistant to control. When food intake is reduced for weight control, all components of energy expenditure change, including metabolic rate at rest (resting energy expenditure [REE]), metabolic rate of exercise, and adaptive thermogenesis. This means that a change in energy intake influences energy expenditure in a dynamic way. Mechanisms associated with reduction of total energy expenditure following weight loss are likely to be related to decreased body mass and enhanced metabolic efficiency. Reducing calorie intake results in a decrease in body weight, initially with a marked reduction in fat free mass and a decrease in REE, and this change is maintained for several years in a reduced state. Metabolic adaptation, which is not explained by changes in body composition, lasts for more than several years. These are powerful physiological adaptations that induce weight regain. To avoid a typically observed weight-loss and regain trajectory, realistic weight loss goals should be established and maintained for more than 1 year. Using a mathematical model can help clinicians formulate advice about diet control. It is important to emphasize steady efforts for several years to maintain reduced weight over efforts to lose weight. Because obesity is difficult to reverse, clinicians must prioritize obesity prevention. Obesity prevention strategies should have high feasibility, broad population reach, and relatively low cost, especially for young children who have the smallest energy gaps to change.

• 한국기계연구소 소보
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• s.19
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• pp.23-30
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• 1989

Heat transfer phenomena of solidification process of the phase change material within cylindrical can is studied experimentally. N-Eicosane paraffin wax is used for phase change material and its melting temperature is 309.8 K. In order to achieve higher heat transfer rate of latent heat storage apparatus, fins in made of copper are used in the cylindrical can. If there are fins in cylindrical can, we can know that the inward latent heat energy in paraffin can be effectively transfered to cooling water than if finless.

• Structural Engineering and Mechanics
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• v.58 no.4
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• pp.719-729
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• 2016

The main objective of the present paper is to study the effect of the yield criterion on the magnitude of the strain rate and plastic work rate intensity factors in axisymmetric flow of isotropic incompressible rigid perfectly plastic material by means of a problem permitting a closed-form solution. The boundary value problem consisting of the axisymmetric deformation of a plastic tube is solved. The outer surface of the tube contracts. The radius of the inner surface does not change. The material of the tube obeys quite a general yield criterion and its associated flow rule. The maximum friction law is assumed at the inner surface of the tube. Therefore, the velocity field is singular near this surface. In particular, the strain rate and plastic work rate intensity factors are derived from the solution. It is shown that the strain rate intensity factor does not depend on the yield criterion but the plastic work rate intensity factor does.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.11
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• pp.2122-2127
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• 2009

This study presents the failure rate and repair rate of Superconducting Fault Current Limiter(SFCL) and adjacent distribution equipments. When the fault current penetrated SFCL, the supply of electric power to the customers can be partly continued. It is expected that SFCL makes to improve the reliability index of customers. Contrary to the expectations, the series connection between SFCL and distribution system could deteriorate the reliability index. To evaluate the reliability index in the distribution system including SFCL, the failure rate and repair rate of SFCL are required as well as that of distribution equipments. Also, the insertion of SFCL makes to change the failure rate and repair rate of adjacent equipments. This study proposes a method to calculate the failure rate and repair rate of a component combining SFCL and adjacent equipments.