• Title/Summary/Keyword: internal barrier

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Inundation Simulation on a Vertical Dock Using Finite Element Storm Surge Model (유한요소 폭풍해일 모형을 이용한 직립안벽에 대한 범람모의)

  • Suh, Seung-Won;Lee, Hwa-Young
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.24 no.4
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    • pp.235-246
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    • 2012
  • Typhoon induced surge simulations are done to make an establishment of coastal disaster prevention plan. To apply efficient run-up and overtopping on vertical harbor docks, in which prevailing wet-dry scheme cannot be satisfied due to infinite steepness, an imaginary internal barrier concept introduced and analyzed. Before real application on the Mokpo harbor area, feasibility tests are done on an idealized simple geometry and as a result it is found that the moderate width of the barrier might be 1 m. The threshold value of the minimum wet depth $H_{min}$ for land area, which behaves sensitive role in inundation area and depth, depends on grid size. However it is revealed that 0.01 m is adequate value in this fine finite element with 10 m spacing. A hypothetical typhoon of 100 years return period in central pressure and maximum velocity is generated based on historical tracks. Simulation of possible inundation on Mokpo area is performed with asymmetrical vortex of hypothetical typhoon and wave coupling. Model results show general agreement in pattern compared to other's prediction, however possibility of inundation enlargement is expected in harbor area.

Study on the Conjugate Heat Transfer Analysis Methodology of Thermal Barrier Coating on the Internal Cooled Nozzle (내부냉각노즐의 열차폐코팅을 위한 복합열전달 해석기법 연구)

  • Kim, Inkyom;Kim, Jinuk;Rhee, Dong-Ho;Cho, Jinsoo
    • The KSFM Journal of Fluid Machinery
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    • v.18 no.3
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    • pp.38-45
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    • 2015
  • In this study, two computational methodologies were compared to consider an effective conjugate heat transfer analysis technique for the cooled vane with thermal barrier coating. The first one is the physical modeling method of the TBC layer on the vane surface, which means solid volume of the TBC on the vane surface. The second one is the numerical modeling method of the TBC layer by putting the heat resistance interface condition on the surface between the fluid and solid domains, which means no physical layer on the vane surface. For those two methodologies, conjugate heat transfer analyses were conducted for the cooled vane with TBC layer having various thickness from 0.1 mm to 0.3 mm. Static pressure distributions for two cases show quite similar patterns in the overall region while the physical modeling shows quite a little difference around the throat area. Thermal analyses indicated that the metal temperature distributions are quite similar for both methods. The results show that the numerical modeling method can reduce the computational resources significantly and is quite suitable method to evaluate the overall performance of TBC even though it does not reflect the exact geometry and flow field characteristics on the vane surface.

Effect of Surface Film on Void Behavior in Composite Integrated Structure (표면접착필름이 복합재 일체형 구조물에서의 기공 거동에 미치는 영향)

  • Park, Dong-Cheol;Kim, Yun-Hae
    • Composites Research
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    • v.33 no.3
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    • pp.147-152
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    • 2020
  • In this study, void behavior of composite laminate by local internal pressure gradient due to structural geometry and surface film application condition was experimentally evaluated through fabrication of spar/skin integrated structure specimens. Viscosity comparison and thermal analysis for both carbon fiber prepreg and surface film were conducted and cure characteristic and rate difference were analyzed. 2 types of spar/skin integrated structural specimens were prepared based on different application condition of surface film. Subsequently, those specimens were evaluated through visual surface inspection, non-destructive and destructive inspection. In a specimen #1 with full application of surface film, low pressurized area of composite laminate created by pressure gradient of structural geometry had voids. It exhibited that voids could not be evacuated and were locked in cured laminate by the influence of pre-cured surface film with relatively faster cure rate. In a specimen #2 without surface film, it revealed that all internal voids disappeared in the cured laminate. Therefore, it is verified that surface film acts as barrier film preventing void movement and evacuation during autoclave cure.

Study on Status of Barrier Free Certification & Improvement Strategies (여객자동차 터미널 이동편의시설 BF 실태 및 개선방안 연구)

  • Park, Shin-Won;Cho, Young-Tae
    • Land and Housing Review
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    • v.7 no.4
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    • pp.225-237
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    • 2016
  • This study is to investigate actual condition of passenger terminals, public facilities which are used by unspecified individuals, with high spread effect of certification system of Barrier Free introduced in 2007, evaluate possibility of the certification and prepare an effective way for certification in order to spread and settle the certification system. According to the investigation on the facilities' equipment level of 349 passenger terminals, which being nationally operated, 217 terminals could be certified and non-certified were 58. And, 29 was evaluated as the passenger terminals with high possibility to get Barrier Free certification by small scale of remodeling. The level of Barrier Free of investigated passenger terminals, according to the actual condition with certification index, were 40~55 percent. While the level of Barrier Free of internal facilities of the terminals was over 90percent, the level of sanitary facilities, information facilities, etc. fell short of 50 percents. In this study, pilot project of Barrier Free certification is proposed for enhance of passenger terminal facilities. Moreover, the selection of passenger terminals with high possibility of certification, local governments' strong will as the targets of pilot project for improvement of amenity level and Barrier Free certification and monitoring the project results are the way of the project.

Efficacy comparison of high-genetic barrier nucleos(t)ide analogues in treatment-naïve chronic hepatitis B patients: a network meta-analysis

  • Jaejun Lee;Ahlim Lee;Pil Soo Sung;Jeong Won Jang;Si Hyun Bae;Jong Young Choi;Seung Kew Yoon;Hyun Yang
    • The Korean journal of internal medicine
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    • v.39 no.4
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    • pp.577-589
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    • 2024
  • Background/Aims: Four high-genetic barrier nucleos(t)ide analogues (NAs) for chronic hepatitis B (CHB), namely entecavir (ETV), tenofovir disoproxil fumarate (TDF), tenofovir alafenamide (TAF), and besifovir dipivoxil maleate (BSV), have been established. The aim of this study is to investigate the efficacy of four high-genetic barrier NAs using a network meta-analysis of randomized trials and propensity score-matched cohorts. Methods: Systematic search was performed using PubMed, Cochrane library, and EMBASE and included randomized controlled trials and cohort studies that used propensity score matching. Studies on treatment-naïve CHB patients treated with ETV, TDF, TAF, or BSV were included. Outcomes included alanine aminotransferase normalization and hepatitis B e antigen seroclearance at week 48 and undetectable hepatitis B virus DNA at weeks 48 and 96. Network meta-analysis was performed to synthesize the results. Results: In total, 15,000 patients from 16 studies were included. In terms of 48- and 96-week virologic response (VR), TDF outperformed ETV with statistical significance (48 weeks: odds ratio [OR], 1.38; p < 0.001; 96 weeks: OR, 1.57; p = 0.004). ETV was ranked first for 48-week biochemical response (BR) and outperformed TDF (OR, 0.76; p = 0.028). In the sensitivity analyses, 48-week VR from randomized-controlled trials were compiled, and the same trend toward the superiority of TDF over ETV was found (OR, 1.51; p = 0.030). Conclusions: Four high-genetic barrier NAs were compared, and TDF was more likely to achieve a VR after 48 weeks, while ETV provided a superior BR after 48 weeks.

A Case of Acral Lick Dermatitis in a Dog with Multiple Lesions

  • Kim, Jihee;Kim, Yoonji;Kim, Soomin;Kim, Hyeon-Jin;Lee, Ji-Hye;Kim, Ha-Jung
    • Journal of Veterinary Clinics
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    • v.38 no.4
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    • pp.194-198
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    • 2021
  • A 7-year-old intact male Maltese dog was presented with firm, raised, erythematous, alopecic, and pruritic skin lesions on the right dorsal distal metatarsal region and the tail. The skin lesion started a year ago with a crust-like lesion on the right dorsal distal metatarsal region which gradually swelled as the patient continued to lick and chew without healing. Recently, similar lesions occurred on the tail. Based on the licking history and ruling out other diseases through skin examination, acral lick dermatitis (ALD) was diagnosed. Treatment included antidepressants, preventive antibiotics, topical corticosteroid, and wearing Elizabethan collar as a physical barrier. After three weeks, the lesion on the hind limb healed entirely. However, the tail lesion recurred as it was able to lick the tail again with a type of an E-collar. This case shows that it is essential to block the contact lesion and provide medical treatment until the lesion has been completely resolved for successful management of ALD.

Factors Influencing the Empoyment Volition of the Female Marriage Immigrants (결혼이주여성의 취업의지에 관한 영향요인 분석)

  • Ryu, Jin-A
    • Journal of Agricultural Extension & Community Development
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    • v.23 no.1
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    • pp.39-51
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    • 2016
  • The purpose of this study is to examine the female marriage immigrants' social unification through their employment. The subjects of this study were 116 female marriage immigrants who lived in Kyungi-do. This study analyzed employment desire, barrier and volition differences of female marriage immigrants between their socio-demographic factors and effects of their employment desire and barrier to employment volition. Results of this study; First, desire of maintenance of livehood and self esteem to employment incresed with age. Second, there were differences in desire of maintenance of livehood and self esteem to employment between their countries of origins. Third, employment volition and self esteem to employment increased with level of education. Fourth, there were differences in employment volition and self esteem to employment between the length of residence in Korea. Fifth, employment desire and self esteem to employment increased with ability to Korean, but internal barrier of employment decreased by ability to Korean. Sixth, desire of identity from employment and self esteem to employment increased with the number of children. Seventh, employment desire influenced employment volition, self efficacy and self esteem to employment.

Serious Blood-Brain Barrier Disruption after Coil Embolization of Unruptured Intracranial Aneurysm : Report of Two Cases and Role of Immediate Postembolization CT Scan

  • Lee, Kyung-Kyu;Kang, Dong-Hun;Kim, Yong-Sun;Park, Jae-Chan
    • Journal of Korean Neurosurgical Society
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    • v.50 no.1
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    • pp.45-47
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    • 2011
  • Abnormal contrast enhancement on brain computed tomography (CT) scan after diagnostic or interventional angiography is not rare, and has known to be induced by temporary blood-brain barrier (BBB) disruption from contrast media. Furthermore, it has been regarded as clinically subtle, but reported to have no symptom or mild transient symptoms. However, we recently experienced two cases of serious BBB disruption during the acute period after coiling of an unruptured intracranial aneurysm. One patient presented with an unruptured paraclinoid internal carotid artery (ICA) aneurysm on the right and the other with an unruptured right supraclinoid ICA aneurysm. Both patients showed similar findings on immediate postembolization CT scan and clinical courses after coiling. Typical radiological, clinical characteristics of BBB disruption were described. In addition, the role of immediate postembolization CT scan are also discussed.

High Temperature Oxidation Behavior of Plasma Sprayed $ZrO_2$ Having Functionally Gradient Thermal Barrier Coating

  • Park, Cha-Hwan;Lee, Won-Jae;Cho, Kyung-Mox;Park, Ik-Min
    • Corrosion Science and Technology
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    • v.2 no.3
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    • pp.155-160
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    • 2003
  • Plasma spraying technique was used to fabricate functionally graded coating (FGC) of NiCrAIY/YSZ 8wt%$Y_2O_3-ZrO_2$ on a Co-base superalloy (HAYNES 188) substrate. Six layers were coated on the substrate for building up compositionally graded architecture. Conventional thermal barrier coating (TBC) of NiCrAIY/SZ with sharp interface was also fabricated. As-coated FGC and TBC samples were exposed at the temperature of $1100^{\circ}C$ for 10, 50, 100 hours in air. Microstructural change of thermally exposed samples was examined. Pores and microcracks were formed in YSZ layer due to evolution of thermal internal stress at high temperature. The amount of pores and microcracks in YSZ layer were increased with increasing exposure time at high temperature. High temperature oxidation of coatings occurred mainly at the NiCrAIY/YSZ interface. In comparison with the case of TBC. the increased area of the NiCrAIY/YSZ interface in FGC is likely to attribute to forming the higher amount of oxides.

The Blood-Brain Barrier Permeability and Pharmacokinetics of Nitrone Based Spin Trapping Agent, $\alpha$-Phenyl-n-tert-Butyl Nitrone (PBN) in Rats (흰쥐에서 nitrone계 항산화제인 $\alpha$-phenyl-n-tert-butyl nitrone(PBN)의 뇌 투과성 및 체내동태)

  • 이나영;강영숙
    • YAKHAK HOEJI
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    • v.46 no.2
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    • pp.124-128
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    • 2002
  • The nitrone-based free radical trapping reagent, $\alpha$-phenyl-n-tert-butyl nitrone (PBN) has been proposed as therapeutic agent for stroke. We used this for model drug of development of new drug for neuroprotection. The purpose of this study was to evaluate the blood-brain barrier (BBB) permeability of PBN in Sprague-Dawly (SD) rats. The BBB transport of PBN was investigated in SD rats using internal carotid artery perfusion (ICAP) method at a rate of 4 mι/min for 15 second. We also obtained pharmacokinetic parameters of PBN using single intravenous injection technique. When we estimated BBB permeability of PBN with ICAP method, the brain volume of distribution of PBN was 60.0 $\pm$ 12.0 $\mu\textrm{g}$/ι. The brain uptake of PBN after IV injection at 120 min was 0.15 $\pm$ 0.01%ID/g. The PBN was transported to the brain through the BBB well in rats, because PBN is small molecule (MW 177) and lipid-soluble (log P 1.23) compound.