• Fashion & Textile Research Journal
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• v.12 no.4
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• pp.531-537
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• 2010

The purpose of this study was to review physiological responses and subjective sensations in the cold environment when the subjects wore ensemble with different clo values. Seven healthy male subjects participated in this experiment. This experiment was conducted in a climatic chamber with $-10^sC$ and 50%RH. Subjects wore five different kinds of ensemble[C1 (4.453 clo), C2 (3.452 clo), C3 (2.865 clo), C4 (2.387 clo), and C5 (2.280 clo)]. The experiment was composed of 20 min of rest period, 20min of treadmill exercise(6 km/h) period, 30 min of recovery period. We monitored skin temperature on 7 sites, clothing microclimate and subjective sensations. The clo value had positive correlations with mean skin temperature and clothing microclimate. The subjects feel more warm and humid as the clo value goes up. The subjects reported comfort when they wore C1 and C2 ensemble having over 3 clo value. However, they felt less comfortable during the exercise period since there was high humidity. Skin temperature on the extremities were more dramatically changed by the exercise rather than clo value. Thus it seems that in the cold environment, heat balance can mostly be controlled by the choice of clothing, and the clothes with high clo values can provide higher insulation. In conclusion, our findings suggest that it would be more effective to control clo value depending on the activity level for maintaining comfort level in the cold environment.

• Fashion & Textile Research Journal
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• v.22 no.6
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• pp.862-872
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• 2020

This study explores the effects of facemasks on respiratory, thermoregulatory, cardiovascular responses during exercise on a treadmill and at rest. Five male subjects (25.8 ± 0.8 y, 171.8 ± 9.2 cm in height, 79.8 ± 28.1 kg in weight) participated in the following five experimental conditions: no mask, KF80, KF94, KF99, and N95. Inhalation resistance was ranked as KF80 < KF94 < N95 < KF99 and dead space inside a mask was ranked as KF80 = KF94 < N95 < KF99. The surface area covered by a mask was on average 1.1% of the total body surface area. The results showed no significant differences in body core temperature, oxygen consumption (VO2), carbon dioxide production (VCO2), heart rate or subjective perception among the five experimental conditions; however, cheek temperature, respiratory ventilation and blood pressure were greater for KF80 or KF94 conditions when compared to KF99 or N95 conditions (p<0.05). The differences among mask conditions are attributed to the dead space or specific designs (cup type vs pleats type) rather than the filtration level. In addition, the results suggest that improving mask design can help mitigate respiratory resistance from increased filtration.

• Smart Structures and Systems
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• v.33 no.1
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• pp.55-64
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• 2024

This paper proposes a fusion imaging-based coating-defect classification method for steel structures that uses zero-shot learning. In the proposed method, a halogen lamp generates heat energy on the coating surface of a steel structure, and the resulting heat responses are measured by an infrared (IR) camera, while photos of the coating surface are captured by a charge-coupled device (CCD) camera. The measured heat responses and visual images are then analyzed using zero-shot learning to classify the coating defects, and the estimated coating defects are visualized throughout the inspection surface of the steel structure. In contrast to older approaches to coating-defect classification that relied on visual inspection and were limited to surface defects, and older artificial neural network (ANN)-based methods that required large amounts of data for training and validation, the proposed method accurately classifies both internal and external defects and can classify coating defects for unobserved classes that are not included in the training. Additionally, the proposed model easily learns about additional classifying conditions, making it simple to add classes for problems of interest and field application. Based on the results of validation via field testing, the defect-type classification performance is improved 22.7% of accuracy by fusing visual and thermal imaging compared to using only a visual dataset. Furthermore, the classification accuracy of the proposed method on a test dataset with only trained classes is validated to be 100%. With word-embedding vectors for the labels of untrained classes, the classification accuracy of the proposed method is 86.4%.

• Journal of Periodontal and Implant Science
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• v.30 no.3
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• pp.491-504
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• 2000

In clinical therapy, the current goal of dental implants is to enhance quantity and quality of osseointegration. Surface roughness and oxide structure are considered to influence the behavior of adherent cells. The purpose of this study is to evaluate the effect of different surface treatment on cellular response. The attachment and proliferation of osteoblast-like cell on sandblasted, sandblasted and etched, thermal oxidated surfaces have been compared. Sandblasting was done with $Al_2O_3$ particles(grain size of $50{\mu}m$), etching was processed with $NH_4OH$ : $H_2O_2$ : $H_2O(1:1:5)$ at $90^{\circ}C$ for 1 minute. Thermal oxidation was followed sandblasting and etching at $400^{\circ}C$, $600^{\circ}C$, $800^{\circ}C$ for 2 hours. Measurement of surface roughness after the different treatment did not show any differences of Ra value between terated surfaces. Cell attachment and proliferation were increased during experiment period, but no difference was observed. SEM evaluation revealed a similar pattern of osteoblast-like cells, well attached with dendritic extension and producing numerous matrix vesicles on cell surface. The results of this study showed that oxide layer alteration by thermal oxidation did not affect the attachment and proliferation of osteoblast-like cells. This suggests the possibility that the cellular responses are further influenced by surface roughness than titaniun oxide structure.

• The Korean Journal of Pain
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• v.13 no.2
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• pp.164-174
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• 2000

Background: After an injury to tissue such as the skin, hyperalgesia develops. Hyperalgesia is characterized by an increase in the magnitude of pain evoked by noxious stimuli. It has been postulated that in the mechanism of hyperalgesia (especially secondary hyperalgesia) and allodynia, a sensitization of central nervous system such as spinal dorsal horn may contribute to development of hyperalgesia. However, the precise mechanism is still unclear. In the present study, we investigated the roles of N-methyl-D-aspartate (NMDA) receptor and nitric oxide (NO) system in the mechanism of hyperalgesia, and their relations with c-fos expression Methods: Inflammation was induced by injection of complete Freund adjuvant (CFA) into unilateral hindpaw of Sprague-Dawley rat. Behavioral studies measuring paw withdrawal responses by von Frey filaments and paw withdrawal latencies by radiant heat stimuli and stainings of nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase and c-fos immunoreactivity were performed. The effects of MK-801, an NMDA receptor blocker and $N^\omega$-nitro-L-arginine (L-NNA), a nitric oxide synthase (NOS) inhibitor were evaluated. Results: 1) Injection of CFA induced mechanical allodynia, mechanical hyperalgesia and thermal hyperalgesia. And it increased the number of NADPH-diaphorase positive neurons and c-fos expression neurons. 2) MK-801 inhibited mechanical hyperalgesia and thermal hyperalgesia induced by CFA and reduced the number of NADPH-diaphorase positive neurons and c-fos expression neurons. 3) L-NNA inhibited the thermal hyperalgesia and reduced the number of NADPH-diaphorase positive neurons, but did not affect the number of c-fos expression neurons. Conclusions: These results suggest that in the mechanism of mechanical hyperalgesia, NMDA receptor but not NO-system is involved and in the case of thermal hyperalgesia both NMDA receptor and NO system are involved. NO system did not affect the expression of c-fos, but c-fos expression and NOS activity were dependent on the activity of NMDA receptor.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.6
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• pp.134-142
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• 2012

This paper presents a study of system identification on the tilt response of the L-type retaining wall located at Tanhyun 11th ACE Apartment, Ilsan in order to understand mechanism how the structure behaves in operational conditions and to provide a reference tilt values for assessing structural abnormality. The retaining wall was extraordinarily tall (14m) in urban area so the long-term monitoring system had been installed with 3 tilts-meters and 9 temperature sensors operational from Oct 2004 upto Nov 2007. By using 5-months continuous data in which all the 12 channels were up and running, the two prediction models, 1) the linear model, and 2) the state-space equation (SSE) model, have been identified by finding the best fitness model among all possible 511 combinations of input temperatures out of the 9 temperatures. The linear model which was simple in the model structure achieved the validation fittness of 68% due to the fact that the static model wasn't able to represent thermal dynamics. The SSE model achieved the validation fitness of 90% which was quite accurate considering various unexpected noises happening in field measurements.

• Steel and Composite Structures
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• v.18 no.1
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• pp.187-212
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• 2015

In this paper, various four variable refined plate theories are presented to analyze vibration of temperature-dependent functionally graded (FG) plates. By dividing the transverse displacement into bending and shear parts, the number of unknowns and governing equations for the present model is reduced, significantly facilitating engineering analysis. These theories account for parabolic, sinusoidal, hyperbolic, and exponential distributions of the transverse shear strains and satisfy the zero traction boundary conditions on the surfaces of the plate without using shear correction factors. Power law material properties and linear steady-state thermal loads are assumed to be graded along the thickness. Uniform, linear, nonlinear and sinusoidal thermal conditions are imposed at the upper and lower surface for simply supported FG plates. Equations of motion are derived from Hamilton's principle. Analytical solutions for the free vibration analysis are obtained based on Fourier series that satisfy the boundary conditions (Navier's method). Non-dimensional results are compared for temperature-dependent and temperature-independent FG plates and validated with known results in the literature. Numerical investigation is conducted to show the effect of material composition, plate geometry, and temperature fields on the vibration characteristics. It can be concluded that the present theories are not only accurate but also simple in predicting the free vibration responses of temperature-dependent FG plates.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.1
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• pp.1-12
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• 2011

This study tests the performance of the recommended winter dress OnMapsi for an office worker through the analysis of skin temperature changes according to the heating environment. We tested and compared the effects of with/without undergarments for 4 male subjects in an artificial-climate chamber with two air temperatures of $19^{\circ}C$ and $22^{\circ}C$, $50{\pm}10%$ R.H. During the 60 minute experiment that simulated office work, the subjective feelings (that included thermal, humidity and comfort sensation, and skin temperature) were measured at equal intervals. The results show that the forehead and chest skin temperatures were not affected by air temperature or clothing type, while the hand and foot skin temperatures were affected at $0.3-0.9^{\circ}C$ depending on clothing type and $1.9-2.2^{\circ}C$ depending on air temperature. The mean skin temperature was decreased by the experimental time pass more with regular formal wear than with OnMapsi. The second experiment located the ambient temperature in which subjects wearing OnMapsi show equal skin temperaturesto those without undergarments at $22^{\circ}C$. Therefore it is possible to decrease heating temperatures to $18-21^{\circ}C$ in the office for winter OnMapsi wear that produces a skin temperature and thermal sensation that is the same as those at $22^{\circ}C$.

• Korean Journal of Materials Research
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• v.20 no.11
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• pp.623-627
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• 2010

Semiconducting metal oxides have been frequently used as gas sensing materials. While zinc oxide is a popular material for such applications, structures such as nanowires, nanorods and nanotubes, due to their large surface area, are natural candidates for use as gas sensors of higher sensitivity. The compound ZnO has been studied, due to its chemical and thermal stability, for use as an n-type semiconducting gas sensor. ZnO has a large exciton binding energy and a large bandgap energy at room temperature. Also, ZnO is sensitive to toxic and combustible gases. The NO gas properties of zinc oxide-single wall carbon nanotube (ZnO-SWCNT) composites were investigated. Fabrication includes the deposition of porous SWCNTs on thermally oxidized $SiO_2$ substrates followed by sputter deposition of Zn and thermal oxidation at $400^{\circ}C$ in oxygen. The Zn films were controlled to 50 nm thicknesses. The effects of microstructure and gas sensing properties were studied for process optimization through comparison of ZnO-SWCNT composites with ZnO film. The basic sensor response behavior to 10 ppm NO gas were checked at different operation temperatures in the range of $150-300^{\circ}C$. The highest sensor responses were observed at $300^{\circ}C$ in ZnO film and $250^{\circ}C$ in ZnO-SWCNT composites. The ZnO-SWCNT composite sensor showed a sensor response (~1300%) five times higher than that of pure ZnO thin film sensors at an operation temperature of $250^{\circ}C$.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.199-199
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• 2013

The distinctive cellular and mitochondrial dysfunctions of a human epithelial lung cancer cell line (H460) from a human lung fibroblastic normal cell line (MRC5) have been studied by dielectric barrier discharge (DBD) plasma treatment. The DBD plasma device have generated large amount of H2O2 and NOx in culture media which is dependent on plasma exposure time. It is found that the cell number of lung cancer cell H460 has been reduced more than the lung normal cell MRC5 as being increased exposure and incubation time. Also these both cell lines have showed mitochondria fragmentation under 5 minutes' plasma exposure, which is a clue of apoptosis. It is noted in this study that AnnexinV staining has showed not only early apoptosis, but also late apoptosis in lung cancer cell H460. Mitochondria enzyme activity and ATP generation have been also much reduced in lung cancer cell H460. Their mitochondrial membrane potential (${\Delta}{\psi}m$) has been found to be reduced in magnitude and shifted to the induced-potential level of cccp, while MRC5 mitochondrial membrane potential has been shifted slightly to that. These distinctively selective responses of lung cancer cell H460 from lung normal cell MRC5 gives us possibility of applying plasma to cancer therapy.