• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2000년도 유체기계 연구개발 발표회 논문집
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• pp.359-365
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• 2000

Port facilities and marine structures used in marine environment were encountered to corrosion damages because of the influence of $Cl^-$. Generally, to protect these accidents, mainly applied anti-corrosion paint and epoxy coating. But it was still remained erosion-corrosion damage such as impingement erosion, cavitation erosion, deposit attack. There was needs to develope the new coating materials to protective those corrosion damages. This paper, polyester glass flake, vinylester glass flake lining and epoxy coating for SS were investigated electrochemical tests and cavitation erosion test for corrosion behaviour under sea water. The main results obtained are as follows, 1) Surface of epoxy coating appear erosion pin hole but surface of polyester glass flake and vinylester glass flake lining do not appear erosion pin hole after impingement-cavitation erosion test in sea water. 2) Weight loss of polyester glass flake and vinylester glass flake lining do not occur after impingement-cavitation erosion test in sea water. 3) Corrosion current density of polyester glass flake lining less drained than epoxy coating and substrate under corrosion potential.. 4) Corrosion current density of vinylester glass flake lining with three coating less drained than that of polyester glass flake lining with two coating.

• KIEAE Journal
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• 제4권2호
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• pp.49-56
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• 2004

This study intends to propose the fundamentals of 'Ecovillage' design by researching into the cycle system of material of 'Crystalwaters' which is having been in charge of a leading role of GEN since 1996 (GEN was formed in 1996) as Ecovillage in Australia. First, to secure the water resources, we can store up rain and the water of valley, and dam. Second, we are able to use the natural filter apparatus, do tree-planting of roof to gain better quality of water. Third, it is to save the energy as supplying water. For it, we make the best of a gravity that is one of the cycle principle of water. Forth, to build a Dam can make a site of scenic beauty, do the role of recreation place and provide against emergencies (a fire, drought) as well as make a mild climate. Fifth, it can reduce the environment load because of sewage and garbage as making it compost. This is possible by treating biologically using composting apparatus of the dry or wet process. Sixth, it is to reduce the environmental pollution as to discharge seperating a recycable waste, an organic matter being able to make it compost. Finally, first of all, environmentally friendly inhabitant consciousness from lifestyle and production style plays an importent part for water cycle and the ecological cycle of waste and sewage.

• 해양환경안전학회지
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• 제27권3호
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• pp.447-456
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• 2021

Methods for predicting the ultimate/buckling strength of ship structures have been extensively improved in terms of design formulas and analytical solutions. In recent years, the design strategy of ships and offshore structures has tended to emphasize lighter builds and improve operational safety. Therefore, the corresponding geometrical changes in design necessitate the use of high-tensile steel and thin plates. However, the existing design formulas were mainly developed for thick plates and mild steels. Therefore, the calculation methods require appropriate modification for new designs beased on high-tensile steel and thin plates. In this study, a modified formula was developed to predict the ultimate strength of thin steel plates subjected to compressive and shear loads. Based on the numerical results, the effects of the yield stress, slenderness ratio, and loading condition on the buckling/ultimate strength of steel plates were examined, and a newly modified double-beta parameter formula was developed. The results were used to derive and modify existing closed-form expressions and empirical formulas to predict the ultimate strength of thin-walled steel structures.

• The Plant Pathology Journal
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• 제39권3호
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• pp.303-308
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• 2023

The global climate change and international trade have facilitated the movement of plants across borders, increasing the risk of introducing novel plant viruses in new territories. Ixora coccinea exhibited virus-like foliar symptoms, including mosaic and mild mottle. An Oxford Nanopore Technologies-based compact and portable MinION platform was used to identify the causal viral pathogen. The complete genome sequence of jasmine virus H (JaVH; 3867 nt, JaVH-CNU) was determined and found to share 88.4-90.3% nucleotide identity with that of Jasminum sambac JaVH isolate in China. Phylogenetic analysis based on the complete amino acid sequences of RNA-dependent RNA polymerase and coat protein revealed that JaVH-CNU was grouped separately with other JaVH isolates. This is the first report of a natural JaVH infection of I. coccinea. The application of rapid nanopore sequencing for plant virus identification was demonstrated and is expected to provide accurate and rapid diagnosis for virus surveillance.

• 수산해양기술연구
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• 제31권4호
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• pp.413-422
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• 1995

각종 환경 조건에서 진동 캐비테이션 침식-부식 시험 장치에 의해 연강(SS41)의 캐비테이션 침식-부식 손상 거동에 관한 연구를 한 결과 다음과 같은 결론을 얻었다. 1) 해수 중에서 캐비테이션 침식-부식 손상 거동은 중앙부와 테두리 부에서 거의 비슷한 정도로 발생하여 성장되지만, 증류수 중에서는 테두리부에서 손상이 먼저 발생한 다음 중앙부에도 손상이 점차 일어난다. 2) 비저항이 낮은 수도수 중의 캐비테이션 침식-부식 손상은 초기에는 비저항이 높은 증류수중에서의 것보다 증가하지만 시간이 경과하면서 CaCO 하(3)의 피막 형성에 의해 둔화된다. 3) 케비테이션 침식-부식 손상 특성은 잠복기, 증가기, 감소기 및 안정기의 4단계로 구분된다.

• Tribology and Lubricants
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• 제26권1호
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• pp.14-20
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• 2010

Tribological properties of nanoporous structured alumina film was investigated. Alumina film (AAO: anodic aluminum oxide) of $60{\mu}m$ thickness having nanopores of 45 nm diameter with 105 nm interpore-diatance was fabricated by mild anodization process. Reciprocating ball-on-flat sliding friction tests using 1 mm diameter steel ball as a counterpart were carried out with wide range of normal load from 1 mN to 1 N in an ambient environment. The morphology of worn surfaces were analyzed using scanning electron microscopy. The friction coefficient was strongly influenced by the applied normal load. Smooth layer patches were formed on the worn surface of both AAO and steel ball at relatively high load (100 mN and 1 N) due to tribochemical reaction and compaction of wear debris. These tribolayers contributed to the lower friction at high loads. Extremely thin layer patches, due to mild plastic deformation of surface layer, were sparsely distributed on the worn surface of AAO at low loads (1 mN and 10 mN) without the evidence of tribochemical reaction. Delaminated wear particles were generated at high loads by fatigue due to repeated loading and sliding.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제8권1호
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• pp.91-95
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• 2005

HCV의 가족 내 집단 감염은 드물게 발생하며 배우자에서 감염의 위험이 가장 높고 수직 감염의 빈도는 매우 낮게 보고되고 있다. 저자들은 환자와 환자의 어머니, 외할머니, 이모, 이종 사촌 언니에서 HCV 감염이 확인되어 가족 구성원의 50%가 HCV에 감염된 극히 드문 가족 내 집단 감염을 경험하였기에 문헌 고찰과 함께 보고한다.

• 한국치위생학회지
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• 제19권2호
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• pp.161-172
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• 2019

Objectives: This study aimed to analyze the correlation between oral function, oral environment, and brain cognitive function in the elderly. Methods: The subjects were 60 users of senior community center and elderly day care center. The survey was conducted from November to December 2018. Subjects were assessed by oral examination and myofunction test. Oral myofunction was measured using $IOPI^R$ and Lip de $Cum^R$. Survey data were analyzed using the statistical programs of PASW Statistics ver. 18.0. Results: Tongue muscle strength and lips muscle strength was higher in males than in females. The tongue and lip strengths were higher in the <81 years old group than the ${\geq}81$ years old group. Functional tooth analysis showed that there was a ${\geq}15$ teeth group ($40.91{\pm}7.36$) and a <15 teeth group ($32.52{\pm}7.14$). Lip muscle strength analysis showed that the ${\geq}15$ teeth group ($10.54{\pm}3.40$) was higher than the <15 teeth group ($8.20{\pm}2.41$, p<0.05). Tongue muscle strength, lumbar muscle strength, and functional tooth number were lower in the elderly subjects with mild cognitive impairment. Cognitive function was significantly correlated with functional tooth number (r=0.386, p<0.001), tongue strength (r=0.478, p<0.001), and lip strength (r=0.281, p<0.05). Tongue strength was significantly correlated with lip strength (r=0.360, p<0.001) and functional tooth number (r=0.633, p<0.001). Lip strength was significantly correlated with functional tooth number (r=0.376, p<0.001). Conclusions: These results showed that age and functional tooth number influenced oral muscle strength and that the number of functional teeth and oral muscle strength were low in the elderly with mild cognitive impairment. Oral myofunction training and oral care program are suggested to improve the quality of life of the elderly.

• 한국전자통신학회논문지
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• 제17권6호
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• pp.1207-1212
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• 2022

4차 산업혁명 시대의 차세대 미디어 기술인 실감미디어는 사용자 경험을 최적화 하는 환경을 통해 체험하는 기술로 이슈화 되고 있고, 보건·헬스케어 융·복합분야로 빠르게 발전하고 있다. 노년층의 인구 증가로 만성질환의 증가, 인지훈련 및 재활분야의 인프라와 전문인력의 부족으로 이를 해결하기 위해 실감미디어 기술과 서비스를 채택하고 있다. 이에 본 연구는 인지 재활이 필요한 경도인지장애 MCI(: Mild cognitive impairment) 대상자를 대상으로 인지능력과 일상생활 활동능력을 향상시키는 목적으로 인지 훈련 시스템을 설계하고 구현하였다. 향후 AI와 BigData 기반의 지능형 인지재활 통합 플랫폼으로 쌍방향 컴뮤니케이션과 즉각적인 피드백이 존재하는 통합 서비스 플랫폼을 연구과제로 남긴다.

• The Plant Pathology Journal
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• 제22권2호
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• pp.164-167
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• 2006

An immunocapture reverse transcription-polymerase chain reaction (IC/RT-PCR) was developed for simultaneous detection of two pepper-infecting RNA viruses, Pepper mud mottle virus (PMMoV) and Tobacco mild green mosaic virus (TMGMV). The assay could be performed in a single tube for simultaneous and sensitive detection of these tobamoviruses. This detection system revealed thousand-fold increase in detection sensitivity compare to ELISA. This method could save time and reagent cost compare to common RT-PCR which needs several reactions and several procedures of viral RNA extractions for the same number of samples.