• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.7 no.1
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• pp.51-58
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• 2011

Due to enhanced sealing and insulation of buildings, extensive use of glasses for building envelopes and increased use of heat generating office equipments, energy consumption of modem buildings for cooling is steadily increasing. With outdoor air cooling(ODAC) system, cooling load can be reduced by exchanging indoor air with the cold outdoor air during spring and fall seasons. If ODAC is operated based only on temperature, total cooling load may virtually increase if the outdoor humidity is high. To overcome this problem, ODAC should be controlled based on enthalpy. In this work energy saving characteristics of enthalpy controlled ODAC is studied using dynamic simulation. The result shows that cooling load can be reduced by 27% by adopting ODAC.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.2
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• pp.35.2-35.2
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• 2015

We present the results of simultaneous observations of the H2O and SiO masers emitted from the circumstellar envelopes (CSEs) of the late-type stars. These observations have been carried out at the four frequency bands (K, Q, W and D bands) using KVN to apply the source frequency phase referencing (SFPR) analysis to the maser lines. We obtain the relative positions between the H2O and the SiO maser spots by using the SFPR method, which are very important to study the physical links between the inner and the outer parts of the CSEs of the late-type stars. The relative positions between the SiO maser spots of the different transitions are also obtained very accurately, which are very crucial to investigate the pumping mechanism of the SiO maser lines. From our results, the capability of the simultaneous multi-band observation of KVN is proved to be powerful to study the complicated physical environments of the CSEs and the stellar evolution of the late-type stars.

• Architectural research
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• v.7 no.2
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• pp.47-54
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• 2005

A photoelectric dimming control system for a small private office space with a double skin envelope system was analyzed for the purpose of examining optimum control performances under a variety of daylight conditions. Computer simulations were performed for the three different photosensor types positioned at the center of ceiling in the space. They were applied in both a south and north-facing room. Daylight conditions were a fixed horizontal venetian blind on an external envelope and a retractable shading device on an internal envelope under a clear, intermediate and overcast sky at different times of a day and year. Partially-shielded photosensors provided good control performances providing the required electric light output under clear and intermediate sky conditions. Unshielded photosensors failed to provide necessary illuminance levels producing less electric output and fully-shielded photosensors generally provided excessive light output. Reasonable electric lighting energy savings were achieved except under overcast sky conditions where the control system did not contribute to energy savings due to the less daylight through envelopes. The retractable shading device covering 50% of the internal envelope reduced energy savings up to 19.62%, but the workplane illuminance levels were maintained within recommended ranges. The coefficients of determination between workplane illuminance and photosensor illuminance due to daylight ranged from 0.74 to 0.98. Partially-shielded conditions provided best correlations and the north-facing room yielded stronger correlation than the south-facing room.

• Composites Research
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• v.17 no.1
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• pp.18-28
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• 2004

In order to evaluate the strength of carbody structures of railway rolling stock made of laminated fiber-reinforced composite materials, total laminate approach was introduced. Structural analyses were conducted to check the basic design of hybrid composite carbody structures of the Korean Tilting Train eXpress(TTX) with the service speed of 180km/h. The mechanical tests were also conducted to obtain strengths of composite laminates. The results show that all stress components of composite carbody structures are inside of failure envelopes and total laminate approach is recommended to predict the failure of hybrid composite carbody structures at the stage of the basic design.

• Journal of Korea Multimedia Society
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• v.17 no.2
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• pp.200-207
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• 2014

Blood pressure (BP) is an important vital signal for determining the health of an individual subject. Although estimation of mean arterial blood pressure is possible using oscillometric blood pressure techniques, there are no established techniques in the literature for obtaining confidence interval (CI) for systolic blood pressure (SBP) and diastolic blood pressure (DBP) estimates obtained from such BP measurements. This paper proposes a nonparametric bootstrap technique to obtain CI with a small number of the BP measurements. The proposed algorithm uses pseudo measurements employing nonparametric bootstrap technique to derive the pseudo maximum amplitudes (PMA) and the pseudo envelopes (PE). The SBP and DBP are then derived using the new relationships between PMA and PE and the CIs for such estimates. Application of the proposed method on an experimental dataset of 85 patients with five sets of measurements for each patient has yielded a smaller Cl than the conventional student t-method.

• Applied Microscopy
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• v.3 no.1
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• pp.45-54
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• 1973

The present study is to determine the toxicity of the fungi isolated from foodstuffs by observing the ultrastructural changes in the mouse liver cells. The results as follows: 1. The toxin-producing fungi were screened by the methods of toxin-screening test(cyto-toxicity test against to HeLa cells and thin layer chromatography). 2. All of the experimental animals treated with isolated fungi were observed the focal necrosis and inflammatory infiltration of liver parenchymal cells. 3. It showed the cytoplasmic changes, such as dilatation of rough endoplasmic reticulum (RER), swelling of mitochondria (mi). increased number of lipid droplet (li) and glycogen (gl), detachment of ribosomes (ri) by observing the electron microscopy. 4. Nuclear and nucleolar alteration were also noted the segregation of nucleolar element and irregularity of nuclear envelopes. 5. As a mass screening, the cytotoxicity test using HeLa cells and thin layer chromatography are feasible methods to detection of the mycotoxin producing fungi from various sources.

• 한국태양에너지학회:학술대회논문집
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• 2008.11a
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• pp.190-195
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• 2008

The objective of this research is to determine overall heat transfer coefficients (K-value) of exterior wall, floor, and roof of Nakseonjae, a Korean traditional residence via field measurement of transient heat flow and temperature difference across each envelope component. Heat flow sensors and T-type thermocouple were attached on the internal and the external surface of each building component, and real-time measurement data were collected for the three consecutive summer days. The K-values determined in this research showed good agreement with other results from open literature. Peak and annual thermal loads of the traditional residence estimated by a commercial energy simulation program were compared with those for a current apartment house. The traditional house showed lower annual cooling load than that of the current building. It may caused by the fact that the traditional building has less air-tight envelopes and no fenestration passing direct solar radiation into the space.

• Hwankyungkyoyuk
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• v.9 no.1
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• pp.17-29
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• 1996

'Control of Locus of Reinforcement(LOCR)' is considered one of the main important factors on responsible environmental behaviors(REB). It is defined as 'an individual's perception of his or her ability to bring about change through his or her behavior'. This phychological construct is divided in two, external locus and internal locus. Internal locus of reinforcement is important as predictor for REB. Lately, 'The Environmental Action Internal Control Index:EAICI' was developed. It is a valid and reliable instrument to measure relationships of two variables. The purposes of this study were to analyse the orientation of LOCR in high school students and relations with LOCR to REB. By the results, EAICI scores of total students, males, females are 99.83, 95.10, 104.56, respectively. LOCR of females was stronger and more internal than one of males. The item scores for behaviors that reduce the amount of household trash by reusing and recycling and convince someone to do this are 4.31, 4.05, respectively. The item scores for behaviors that convince someone to sign a petition regarding on environmental issues, convince someone to reuse envelopes by putting a label over the old address and convince someone to keep car tires properly inflated are 3.09, 3.09, 3.04, respectively. It shows that EAICI scores are dependent upon the degree of the chances and experiences to meet the various environmental events.

• The Journal of the Korea Contents Association
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• v.14 no.3
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• pp.463-469
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• 2014

Safety related devices unconstrained temporally in the process of operation of nuclear power plants could be damaged by the sliding during seismic activity. In this study sliding response of unconstrained objects to the base excitations is studied experimentally and analytically. In experiments static and dynamic tests to determine the coefficient of friction and the shaking table experiments to verify the sliding response of the analytic results were conducted. Numerical solutions by solving the nonlinear differential equations of motion governing sliding were found by the computer program using the step by step acceleration method. The exact solutions of the sliding response to the simple forms of base excitations were found to verify the computer program developed in this study. Relative displacement envelopes were suggested as a colliding criteria of the unconstrained objects.

• Journal of Microbiology
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• v.39 no.3
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• pp.206-212
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• 2001

Catechol and 4-chlorobenzoate (4CBA) which are produced from the biodegradation of a variety of aromatic and chloroaromatics have been recognized as toxic to living organisms. In this study, the toxic effects of catechol and 4-chlorobenzoate on gram-positive and -negative bacteria were examined in terms of survival, morphology, change in fatty acids and membrane protein composition. The survival rate of the organisms during treatment for 6 h was decreased, as the concentration of each aromatic was increased. Escherichia coli and Pseudomonas cells treated with catechol and 4CBA at concentrations causing a significant decrease in their viability, showed destructive openings in their cell envelopes. Bacills subtilis treated with the aromatics were reduced in cell size and Staphylococcus aureus cells displayed irregular rod shapes with wrinkled surfaces. The bacterial cells treated with 20 mM catechol showed increases in unsaturated fatty acids, but several saturated fatty acids were decreased. In the E. coli cells treated with 20 mM catechol, inner membrane proteins of 150 kDa and 105 kDa were decreased. But several kinds of the inner and outer membrane proteins were increased. In B. subtilis treated with 20 mM catechol, several kinds of proteins were increased or decreased in membrane proteins.