• Journal of the Optical Society of Korea
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• v.12 no.4
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• pp.314-318
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• 2008

We investigate the conditions of the complete tunneling of light across a composite barrier made of multiple layers involving metamaterials. It is shown that complete tunneling phenomena are related to the resonance transmission properties of local modes formed in barrier layers and that there are two distinctive kinds of local barrier modes involved in actual complete tunneling: the degenerate inner-barrier mode and the full barrier mode. Complete tunneling occurs via two successive mode couplings: from the incident plane wave to the plane wave in the transmission layer through the direct mediation of these two kinds of local barrier modes.

• Korean Journal of Materials Research
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• v.12 no.3
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• pp.200-204
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• 2002

We fabricated TMR devices which have double oxidized tunnel barrier using plasma oxidation method to form homogeneously oxidized AlO tunnel barrier. We sputtered 10 $\AA$-bottom Al layer and oxidized it by varying oxidation time for 5, 10, 20 sec. Subsequent sputtering of 13 $\AA$ - Al was performed and the matallic layer was oxidized for 120 sec. The electrical resistance changed from 700$\Omega$ to 2700$\Omega$ with increase of oxidation time, while variation of MR ratio was little spreading 27~31% which is larger than that of TMR device of ordinary single tunnel barrier. We calculated effective barrier height and width by measuring I-V curves, from which we found the barrier height was 1.3~1.5 eV, sufficient for tunnel barrier, and the barrier width(<16.2 $\AA$) was smaller than that of directly measured value by the tunneling electron microscopy. Our results may be caused by insufficient oxidation of Al precursor into $Al_2O_3$. However, double oxidized tunnel barriers were superior to conventional single tunnel barrier in uniformity and density. We found that the external magnetic field to switch spin direction of ferromagnetic layer of pinned layer breaking ferro-antiferro exchange coupling was increased as bottom layer oxidation time increased. Our results imply that we were able to improve MR ratio and tune switching field by employing double oxidized tunnel barrier process.

• The Journal of Pediatrics of Korean Medicine
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• v.35 no.4
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• pp.156-166
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• 2021

Objectives The purpose of this study is to confirm the regulate effect of T helper (Th) 2 differentiation that Baekho-tang extract may produce to improves skin lipid barrier damages. Methods Four-weeks-old NC/Nga mice were divided into four groups: control group (Ctrl, n=10), lipid barrier eliminated group (LBE, n=10), Dexamethasone treatment after lipid barrier elimination group (DxT, n=10), and Baekho-tang extract treatment group after lipid barrier elimination group (BHTT, n=10). Baeko-tang extract was administered for 3 days after removal of the skin fat barrier in BHTT group. Then, we identified changes in external symptoms of the skin, factors affecting skin barrier such as potential of hydrogen (pH), filaggrin (FLG), transepidermal water loss (TEWL) and Th2 differentiation factors like Interleukin (IL)-4, Kallikrein Related Peptidase 7 (KLK7) and protease activated receptor 2 (PAR-2) through our immunohistochemistry. Results After lipid barrier elimination, the reduction of morphological skin inflammations was less in BHTT group than in LBE group and DxT group. Also, pH and TEWL were significantly decreased with BHTT group. However, FLG was significantly increased in BHTT group compared to LBE, DxT, and Ctrl group. All kinds of Th2 differentiation factors (IL-4, KLK7 and PAR-2) were also decreased in BHTT compared to the LBE and DxT. Conclusions As a result of this study, BHT administration decreased pH, TEWL, and increased FLG, thus participating in recovering damaged skin barrier. Since Th2 differentiation factors were decreased as well, BHT's regulatory effect in sequential immune reactions may be a possible explanation of how it enhances recovery of the damaged lipid barrier.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.765-779
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• 2003

Physiological lipid mixtures comprised of cholesterol, ceramide and free fatty acid better maintain epidermal homeostasis and have been recently used for dermatoses induced by skin barrier damage, for example for atopic dermatitis and xerotic skin. Itching and dry atopic dermatitis of the skin may be related to altered skin barrier function. In a previous study, the use of multi-lamellar emulsion (MLE), which is a lipid mixtures containing cholesterol, pseudoceramide and free fatty acid, has been shown to accelerate the recovery of the epidermal permeability barrier. In this study, we assessed the efficacy of MLE compared with a currently used anti-itch moisturizer (AIM), the active ingredients of which are menthol and camphor, on barrier recovery after barrier disruption. To clarify the effect of MLE and AIM after acute barrier perturbation, we measured the relation between transepidermal water loss (TEWL) and the barrier recovery rate at 3, 6, 24, and 48 hours after tape stripping hairless mice and then observed changes in the stratum corneum (SC), including the intercellular lipid structure and secretion of lamellar bodies, by electron microscopy. MLE treated skin recover skin barrier function more rapidly, and AIM treated skin delayed barrier repair. Morphological changes in the epidermis, of MLE treated skin revealed well-conserved lipid multi-lamellar structures at 24 h after tape stripping, whereas AIM treated skin showed altered lamellar bilayers within the SC interstices at 48 h. In addition, MLE treated skin showed an increase in the number of LBs and in their secretions and a decrease in the number of SC layers versus AIM treated skin. These results suggest that MLE may accelerate the production of an epidermal permeability barrier in hairless mice by increasing the number and secretion of LB and improve the dryness and itch associated with an altered epidermal permeability barrier.

• Korean Journal of Materials Research
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• v.20 no.6
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• pp.338-343
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• 2010

As an alternative to the W plug used in MOSFETs, a Cu plug with a NiSi contact using Ta / TaN as a diffusion barrier is currently being considered. Conventionally, Ni was first deposited and then NiSi was formed, followed by the barrier and Cu deposition. In this study, Ti was employed as a barrier material and simultaneous formation of the NiSi contact and Cu plug / Ti barrier was attempted. Cu(100 nm) / Ti / Ni(20 nm) with varying Ti thicknesses were deposited on a Si substrate and annealed at $4000^{\circ}C$ for 30 min. For comparison, Cu/Ti/NiSi thin films were also formed by the conventional method. Optical Microscopy (OM), Scanning Probe Microscopy (SPM), X-Ray Diffractometry (XRD), and Auger Electron Microscopy (AES) analysis were performed to characterize the inter-diffusion properties. For a Ti interlayer thicker than 50 nm, the NiSi formation was incomplete, although Cu diffusion was inhibited by the Ti barrier. For a Ti thickness of 20 nm and less, an almost stoichiometric NiSi contact along with the Cu plug and Ti barrier layers was formed. The results were comparable to that formed by the conventional method and showed that this alternative process has potential as a formation process for the Cu plug/Ti barrier/NiSi contact system.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.823-827
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• 2005

Barrier ribs in the plasma display panel (PDP) function to maintain the discharge space between the glass plates as well as to prevent optical crosstalk. Patterning of barrier ribs is one of unique processes for making PDP. Barrier ribs could be formed by screen-printing, sand blasting, etching, and photolithographic process. In this work photosensitive barrier rib pastes were prepared by incorporating binder polymer, solvent, functional monomers photoinitiator, and barrier rib powder of which surface was treated with fumed silica particles. Studies on the function of materials for the barrier rib paste were undertaken. After optimization of paste formulation and photolithographic process, it was applied to the photosensitive barrier rib green sheet and was found that photolithographic patterning of barrier ribs could be formed with good resolution up to $110{\mu}m$ height and $60{\mu}m$ width after sintering.

• Korean Journal of Adult Nursing
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• v.17 no.1
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• pp.139-148
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• 2005

Purpose: The specific aims of this study was to find out the barrier to smoking cessation intervention in clinical practice among clinical nurses and compare them in high barrier group with those in the low barrier group. Method: The sample of this study consisted of 738 nurses practicing in general hospitals with over 400 beds throughout the country. The questionnaire was adopted from the 'Oncology Nurse's Tobacco Control Survey' used in the United Stated by Sarna et al.(2001). Result: Age, marital status, hospital experience, position were the variables related to the mean score of subjective resource insufficiency. The perception that the patient was not motivated to quit smoking was the most commonly identified barrier in low barrier group and the second most common barrier in high barrier group. Conclusion: Younger, with less clinical experience, single, staff nurses were the characteristics of nurses in the high barrier group. The smoking cessation educational program should be targeted to these populations. Further research is needed to develope strategies to reduce the perception associated with barriers in delivery of tobacco cessation interventions.

• Korean Institute of Interior Design Journal
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• v.22 no.5
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• pp.344-356
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• 2013

Due to implementation of legislations for translation poor such as handicapped people, elderlies, children most public buildings are now integrating barrier free design methods. However, barrier free design is still considered as constraints of physical elements that only serve to meet functional aspects for minors and conflict with designs of the space. The authors believe that it is time that barrier free design is considered not as constraints but opportunities that both meet functional and aesthetical needs serving the growing population of transportation poor and others as well. This paper has looked into characteristics of transportation poor and barrier free design elements of passenger terminals and developed 4 categories of design methods. applied by using human sense, form, furniture, and architectural elements. Then the authors analyzed Gunsan International and coastal passenger terminal existing conditions which is considered to be designed to meet barrier free guidelines and legislations through the developed design categories and elements. The result turned out that the subject in regard of barrier free designs for transportation poor lack various applications such as forms that can be used as symbolic and directional elements that assists as wayfinding cues. Also, flexible and multi functional approaches in furniture arrangements, structural approaches are needed.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.6
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• pp.857-865
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• 2006

The submerged barrier, employed in a reactor, divided a reactor into sludge settling zone and mixing zone according to flow type. In spite of mixing in the mixing zone, the lower part of sludge settling zone than the top of barrier was in a steady flow due to the barrier, which prevented the turbulent flow, produced from the mixing zone, from being diffused into the sludge settling zone. Therefore, the sludges in the mixing zone flowed backward over the barrier into the upper part of the sludge settling zone by turbulent flow and settled down in the sludge settling zone by the force of gravity. When barrier/water level ratio was 0.5, most sludges almost did not settle down in tile sludge settling zone because the sludges were directly affected by the turbulent flow, generated from mixer in the mixing zone. At 0.63 of barrier/water level ratio, sludge in the middle part of sludge settling zone rocked from side to side weakly. And sludge in the lower part became piled up on the bottom over this ratio. After 10minutes of sludge settling, the lower part of sludge settling zone was over 5000mg/L of sludge concentration although intial sludge concentration was 2300mg/L. By using the submerged barrier and the flow types, it could transfer sludge from this to that.

• Wind and Structures
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• v.23 no.3
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• pp.171-189
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• 2016

An adjustable, louver-type wind barrier was introduced in this study for improving the running safety and ride comfort of train on the bridge under the undesirable wind environment. The aerodynamic characteristics of both train and bridge due to this novel wind barrier was systematically investigated based on the wind tunnel tests. It is suggested that rotation angles of the adjustable blade of the louver-type wind barrier should be controlled within $90^{\circ}$ to achieve an effective solution in terms of the overall aerodynamic performance of the train. Compared to the traditional grid-type wind barrier, the louver-type wind barrier generally presents better aerodynamic performance. Specifically, the larger decrease of the lift force and overturn moment of the train and the smaller increase of the drag force and torsional moment of the bridge resulting from the louver-type wind barrier were highlighted. Finally, the computational fluid dynamics (CFD) technique was applied to explore the underlying mechanism of aerodynamic control using the proposed wind barrier.