• 한국안전학회지
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• 제34권5호
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• pp.15-21
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• 2019

A rack-type warehouse has the advantage of storing a large amount in a small area by loading goods vertically. But in terms of fire risk, the fire load is very high, which can cause massive damage in the event of a fire. In the United States, research has been actively conducted to minimize the spread of vertical fires, and relevant standards have been established and operated. In Korea, research and related standards are insufficient to prevent the vertical spread of rack-type warehouse fires. In this study, an experimental study was conducted to prevent the vertical spread of a rack-type warehouse fire using a horizontal barrier and in-rack sprinklers. As a result of the test, the horizontal barrier considering the continuous flame prevented the vertical spread of the flame for a certain time. However, the horizontal barrier with continuous flame did not show the effect of preventing continuous flame. The combination of the horizontal barrier and the in-rack sprinkler prevented the vertical spread of fire effectively. In addition, the heat collecting effect through the horizontal barrier was shown and helped the early operation of the in-rack sprinklers.

• Asian Journal of Atmospheric Environment
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• 제8권2호
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• pp.81-88
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• 2014

Noise-barriers on both sides of the roadway (hereafter referred to as double noise-barriers), are a common feature along roads in Korea, and these are expected to have important effects on the near-road air pollution dispersion of vehicle emissions. This study evaluated the double noise-barrier impact on near-road air pollution dispersion, using a FLUENT computational fluid dynamics (CFD) model. The realizable k-${\varepsilon}$ model in FLUENT CFD code was used to simulate vehicle air pollutant dispersion, in around 11 cases of double noise-barriers. The simulated concentration profiles and surface concentrations under no barrier cases were compared with the experimental results. The results of the simulated flows show the following three regimes in this study: isolated roughness (H/W=0.05), wake interface (H/W=0.1), and skimming flow (H/W>0.15). The results also show that the normalized average concentrations at surface (z=1 m) between the barriers increase with increasing double noise-barrier height; however, normalized average concentrations at the top position between the barriers decrease with increasing barrier height. It was found that the double noise-barrier decreases normalized average concentrations of leeward positions, ranging from 0.8 (H/W=0.1, wake interface) to 0.1 (H/W=0.5, skimming flow) times lower than that of the no barrier case, at 10 x/h downwind position; and ranging from 1.0 (H/W=0.1) to 0.4 (H/W=0.5) times lower than that of the no barrier case, at 60 x/h downwind position.

• 공업화학
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• 제10권8호
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• pp.1114-1118
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• 1999

플라즈마 디스플레이 패널(PDP)의 격벽(barrier rib)은 일정한 선폭과 높이를 가져 균일한 방전 공간을 제공하고, 인접한 셀 간의 전기적, 광학적 혼선(crosstalk)을 방지하기 위해 PDP의 하부 유리 기판 패널에 들어가는 구조물이다. 본 연구에서는 사진식각(photolithography)법으로 격벽을 형성하는데 필요한 감광성 격벽 페이스트가 제조되었다. 페이스트는 바인더 고분자인 에틸셀룰로오즈를 BC/BCA = 30/70 wt %인 혼합 용매에 15 wt %로 용해한 다음 관능성 단량체로서TPGDA/PETA = 50/50 wt % 혼합물, 광개시제로서 Irgacur 651 및 격벽 분말을 도입한 다음 전체를 균일하게 분산시켜 제조하였다. 감광성 격벽 페이스트의 각 성분, 조성 및 공정을 최적화하여 소성 후 높이 약 $100{\mu}m$ 에 이르는 PDP용 격벽을 고해상도로 사진식각법으로 얻을 수 있었다.

• 대한한의학회지
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• 제29권1호
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• pp.117-133
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• 2008

Objectives : Since ancient times, Koreans have applied medicinal spabaths for treatment of various diseases. The objective of this study was to investigate the effect of strontium, one of the common ingredients of such baths, experimentally on acute skin barrier damage. Materials and Methods : Male hairless mice, average weight 20g, were divided into six groups. Each group consisted of five mice. The first was the normal, non-treated group. The second was the control group with acute skin barrier damage intentionally induced by TS. The third was the Ba-Sr1 group bathed in 1mg/L strontium chloride before and after inducing acute skin barrier damage by TS. The fourth was the Ba-Sr7 group bathed in 7mg/L strontium chloride before and after inducing acute skin barrier damage by TS. The fifth was the Sr1 group bathed in 1mg/L of strontium chloride only after intentionally inducing acute skin barrier damage by TS. The sixth was the Sr7 group bathed in 7mg/L of strontium chloride only after intentionally inducing acute skin barrier damage by TS. External changes of skin, skin erythema level, transepidermal water loss level, and GOT and GPT level of each group were checked immediately before and after TS, 3 hrs, 5 hrs and 24 hrs after inducing acute skin barrier damage. Then, tissue samples were made and examined for damage to epithelial cells, stratum corneum, change of mucous polysaccharide in dermis and amount of mast cells. Statistical analysis was performed by one way-ANOVA, Scheffe and Duncan for a post hoc test and pairwise comparison for comparing for difference between each time. Statistical significance was achieved if the probability was less than 5% (p<0.05) Results : 1. From skin erythema and TEWL level indicating the function of the skin barrier, we can know that it is helpful to the skin barrier to bathe in a water solution including a low concentration of strontium. 2. In the control group with acute skin barrier damage induced by TS, skin barrier damage persisted until 3-5 hrs and recovered after 5-24 hrs. Differently from the control group, in the case of taking a bath in a water solution including strontium, skin barrier damage recovered after only 3-5 hrs. Therefore, the bath with a water solution including strontium can promote recovery of the skin barrier. 3. Bathing in water solution including a higher concentration of strontium was more beneficial to recovery of skin barrier damage. 4. There was no influence on serum GOT and GPT from bathing in a water solution including strontium. Conclusions : The strontium was effective for recovery and mitigation of acute skin barrier damage induced by tape stripping. I suggest that strontium (Sr) can be used as an external treatment medicine, addedinto bath water to treat acute skin barrier damage.

• 농촌지도와개발
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• 제15권3호
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• pp.433-460
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• 2008

The objectives of this study were to figure out the relationships of factors, e-quality, interactivity, trust and switching barrier, to affect the online customers loyalty. Moreover, e-quality was considered because of the problem of ssability originated from the environment that a lot of information and products are given at online business. This study employs a survey method to empirically test the proposed research model. A survey questionnaire was developed and 100 responses were collected. The data were analyzed using PLS method, a structural equation modeling method. The results of the study indicate that e-quality, interactivity, and trust influence switching barrier and that the switching barrier affects virtual relationship, which has an positive effect on loyalty. This study provides valuable theoretical and practical perspectives that e-quality is the most influential factor on virtual relationship and that, of the three factors of switching barrier, the virtual relationship is the most effective one to prevent customers online from changing their main online shop for products.

• 전기학회논문지
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• 제56권3호
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• pp.583-587
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• 2007

Corona discharge and ozone generation characteristics of a slit dielectric barrier discharge type wire-plate plasma reactor with a third electrode have been investigated. When a third electrode is installed on a slit of the slit barrier, where an intense corona discharge occurs, it is found that a significantly increased ozone output could be obtained. This, however, indicates that the third electrode can activate the corona discharges both of the discharge wire and the slit of the slit barrier in the plasma reactor. As a result, a thin stainless wire, used as the third electrode has a strong effect to influence the corona discharge of the slit and corona wire, especially to the negative corona discharge. Higher amounts of the output ozone and ozone yield, about 1.27 and 1.29 times for the negative corona discharge, can be obtained with the third electrode, which reveals the effectiveness of the third electrode.

• 반도체디스플레이기술학회지
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• 제5권3호
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• pp.33-36
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• 2006

To produce a fine structure with uniform surface of barrier ribs in PDP, acid etching process has been used in manufacture process. It is necessary to understand the mechanism of etching, particularly on the interface of ceramic fillers and matrix glass. We investigated the effect of ceramic fillers (ZnO, $Al_2O_3$) on the microstructure of borate glass system to find an etching mechanism of barrier ribs. The barrier ribs was etched with several steps, dissolving a small amount of residual glass, taking out alumina fillers, and removing a cluster type of ZnO fillers and glass matrix.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.725-727
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• 2009

Lowering the dielectric constant is one of the important issues for the efficiency and the power consumption in the plasma display panel (PDP) industry. This study examined the effect of the addition of ceramic filler (up to 10% of crystalline and amorphous silica, respectively) to a $B_2O_3$-ZnO- $P_2O_5$ glass matrix on the dielectric, coefficient of thermal expansion, etching behaviors and residual stress for the barrier ribs in plasma display panels. The dielectric constant of barrier ribs is affected by containing two types of $SiO_2$ filler for the barrier rib composition in PDP.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 춘계학술대회 논문집
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• pp.577-583
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• 2002

We have made known the study of shape development of interference device for vehicle noise control. It's primary object greatly attenuate the noise due to transport vehicle by small products installed on the noise barrier edge. Also, it is able to improve the insertion loss of a noise barrier without increasing the height of noise barrier. The present time, we set up a newly manufactured products on the noise barrier edge and testify to it's the performance use of an experiment and evaluation for the reduction of railway noise. In this paper the frequency characteristic of interference device of noise barriers with attached newly developed products in terms of shape, absorptive material and split panel, are examined using field test around of railroad.

• 한국연초학회지
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• 제16권1호
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• pp.84-89
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• 1994

Potato virus Y (PVY) is an important viral disease in burley tobacco in Korea and is mostly transmitted by green peach aphid, Myzus penicae, in nature. Effects of barrier nets on the immigration of the aphid population into tobacco fields and on the control of PVY were investigated in 3 tobacco fields with 1.8 m - height polyethylene (PE) nets on their outer - sides in Iseo - Myeon, Wanju - Kun, Cheonbuk. Immigration of aphids to the tobacco yields started at late April and reached maximum at early June. The immigrating aphid population was apparently blocked by the barrier nets to be reduced by 54-73%. PVY severity was also reduced by the barrier nets. However, the control value was variable, ranging 24-67%, which suggests that effect of the PE net barrier on the prevention of aphid-borne virus might be variable depending on the location and slope of the fields.