• 한국전자통신학회논문지
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• 제8권10호
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• pp.1595-1600
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• 2013

기존의 기기분석에 있어서의 미비한 점을 보완한 물질 분석 과정에서 주요 성분의 파괴를 최소화하고져 비파괴형 원적외선 도자기 가마를 이용하여 비파괴형 성분물질을 유지할 수 있는 기기 분석 장치를 개발 하였다. 또한 광폭증폭관(PMT) 기기를 사용하여 뽕잎 차에 함유된 항산화 물질의 형태적 효과를 기존의 기기분석기와 원적외선 도자기 기기를 사용한 것과의 차별화 실험을 통해 그 효과를 측정 하였다. 그 결과 특히 과산화수소를 이용한 항산화 효과를 측정한 결과 성분이 파괴되지 않음을 측정하여 그 효과가 인정 되었기에 이를 보고한다.

• Carbon letters
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• 제18권
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• pp.30-36
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• 2016

Well-dispersed Ag₃VO₄ nanoparticles @polyacrylonitrile (PAN) nanofibers were synthesized by an easily controlled, template-free method as a photo-catalyst for the degradation of methylene blue. Their structural, optical, and photocatalytic properties have been studied by X-ray diffraction, transmission electron microscopy, field-emission scanning electron microscopy equipped with rapid energy dispersive analysis of X-ray, photoluminescence, and ultraviolet-visible spectroscopy. The characterization procedures revealed that the obtained material is PAN nanofibers decorated by Ag₃VO₄ nanoparticles. Photocatalytic degradation of methylene blue investigated in an aqueous solution under irradiation showed 99% degradation of the dye within 75 min. Finally, the antibacterial performance of Ag₃VO₄ nanoparticles @PAN composite nanofibers was experimentally verified by the destruction of Escherichia coli. These results suggest that the developed inexpensive and functional nanomaterials can serve as a non-precious catalyst for environmental applications.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2004년도 춘계종합학술대회
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• pp.623-626
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• 2004

본 논문은 주사형 전자 현미경을 사용하여 간단한 형태의 반도체 소자뿐만 아니라 집적회로의 내부 P-N 접합 층의 깊이를 소자를 파괴하지 않고 패키지 상태 그대로 측정 할 수 있는 방법이다. 전자 현미경에서 주사되는 전자빔의 에너지에다 반도체 내에 여기 되는 전류를 측정하여 이 임계치에서 전자빔의 침투 범위를 산출하여 접합의 깊이를 측정한다. 실제 시판되고 있는 소자를 사용하여 SEM 의 전자 주사빔 에너지를 변화시키면서 외부의 전류 변화를 측정하였다. 소자 내부의 전자와 정공 생성율은 접합에서 더 많이 발생되므로 이를 고려하여 화산 깊이를 측정하였다. 이렇게 측정한 결과와 이후에 소자를 lapping 하여 파괴 측정한 측정치와 비교 한 결과 일치함을 알 수 있었다.

• 대한병리학회지
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• 제52권6호
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• pp.363-368
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• 2018

Background: Vitiligo is a chronic autoimmune disease in which the destruction of melanocytes causes white spots on the affected skin. Janus kinase (JAK) is a family of intracellular, non-receptor tyrosine kinases that transduce cytokine-mediated signals via the JAK-signal transducer and activator of transcription pathway. The aim of the present study is to explore the possible role of JAK1 in the pathogenesis of vitiligo using immunohistochemical methods. Methods: The current study was conducted in a sample of 39 patients who presented with vitiligo and 22 healthy individuals who were age and sex matched as a control group. We used immunohistochemistry to evaluate JAK1 status (intensity and distribution) and assess the percentage of residual melanocytes using human melanoma black 45 (HMB45). Results: Intense and diffuse JAK1 expression was significantly more likely to indicate vitiliginous skin compared to normal skin (p<.001). Strong and diffuse JAK1 expression was associated with short disease duration, female sex, and lower percentage of melanocytes (detected by HMB45) (p<.05). Conclusions: JAK1 may be involved in the pathogenesis of vitiligo, as indicated by intense and diffuse expression compared to control and association with lower percentage of melanocytes detected by HMB45 immunostaining.

• 비교문화연구
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• 제30권
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• pp.97-124
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• 2013

For a long period, vowel reduction has been accepted as one of the most common pronunciation rules in Russian phonology. However, since the rules have been modified in many ways after the influx of loanwords, [a, e, i, o, u, ${\star}$]-including [e, o]-can now be pronounced in unstressed position, obeying the rule of vowel reduction. Especially in Modern Russian, along with the destruction of the consonant pronunciation norm due to some relatively complex changes it underwent palatalization, consonant pronunciation has been simplified, and as a response to such a phenomenon, the specialization of vowel pronunciation rule is now occurring. In other words, in the interrelation between consonants and vowels, as the pronunciation rules for consonants are simplified and thus the contrast between consonants is weakened, the degree of dependence on pronunciation of segment in the vowel pronunciation rule has been elevated. Therefore, the analysis says that the degree of vowel reduction depends on a vowel's distance from a stressed syllable is not enough; the influence of surrounding phonemes-including consonants-or the formative characteristics of words themselves should also be considered. The introduction of Max-noncorner/UnderLex, a/an Licence constraint that is related to non-declension nouns, and that of IdentC[back] and ShareCV[back], which are faithfulness constraint and share constraint respectively that are related to the nature of consonants stresses that vowel pronunciation rules should not be simply viewed as rules for vowels; The rules should be analyzed with emphasis on their correlation with surrounding phonemes.

• 한국표면공학회지
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• 제51권6호
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• pp.354-359
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• 2018

NaCl-induced hot corrosion behavior of ASTM T22 (Fe-2.25Cr-1Mo), T91 (Fe-9Cr-1Mo), T92 (Fe-9Cr-1.8W-0.5Mo), 347HFG (Fe-18-Cr-11Ni), and 310H (Fe-25Cr-19Ni) steels was studied after spraying NaCl on the surface. During corrosion at $600-800^{\circ}C$ for 50-100 h, thick, non-adherent, fragile, somewhat porous oxide scales formed. All the alloys corroded fast with large weight gains owing to fast scaling and destruction of protective oxide scales. Corrosion rates increased progressively as the corrosion temperature and time increased. Corrosion resistance increased in the order of T22, T91, T92, 347HFG, and 310H, suggesting that the alloying elements of Cr, Ni, and W beneficially improved the corrosion resistance of steels. Basically, Fe oxidized to $Fe_2O_3$, and Cr oxidized to $Cr_2O_3$, some of which further reacted with FeO to form $FeCr_2O_4$ or with NiO to form $NiCr_2O_4$.

• Biomolecules & Therapeutics
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• 제29권3호
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• pp.263-267
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• 2021

Periodontal disease is primarily associated with bacterial infection such as dental plaque. Dental plaque, an oral biofilm harboring a complex microbial community, can cause various inflammatory reactions in periodontal tissue. In many cases, the local bacterial invasion and host-mediated immune responses lead to severe alveolar bone destruction. To date, plaque control, non-surgical, and surgical interventions have been the conventional periodontal treatment modalities. Although adjuvant therapies including antibiotics or supplements have accompanied these procedures, their usage has been limited by antibiotic resistance, as well as their partial effectiveness. Therefore, new strategies are needed to control local inflammation in the periodontium and host immune responses. In recent years, target molecules that modulate microbial signaling mechanisms, host inflammatory substances, and bone immune responses have received considerable attention by researchers. In this review, we introduce three approaches that suggest a way forward for the development of new treatments for periodontal disease; (1) quorum quenching using quorum sensing inhibitors, (2) inflammasome targeting, and (3) use of FDA-approved anabolic agents, including Teriparatide and sclerostin antibody.

• Acta Via Serica
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• 제5권2호
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• pp.25-49
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• 2020

This essay, based on an oral presentation, provides the non-specialist, with an evaluation of the Mongols' influence and China and, to a lesser extent, on Russia and the Middle East. Starting in the 1980s, specialists challenged the conventional wisdom about the Mongol Empire's almost entirely destructive influence on global history. They asserted that Mongols promoted vital economic, social, and cultural exchanges among civilizations. Chinggis Khan, Khubilai Khan, and other rulers supported trade, adopted policies of toleration toward foreign religions, and served as patrons of the arts, architecture, and the theater. Eurasian history starts with the Mongols. Exhibitions at the Metropolitan Museum of Art and the Los Angeles County Museum of Art confirmed that the Mongol era witnessed extraordinary developments in painting, ceramics, manuscript illustration, and textiles. To be sure, specialists did not ignore the destruction and killings that the Mongols engendered. This reevaluation has prompted both sophisticated analyses of the Mongols' legacy in Eurasian history. The Ming dynasty, the Mongols' successor in China, adopted some of the principles of Mongol military organization and tactics and were exposed to Tibetan Buddhism and Persian astronomy and medicine. The Mongols introduced agricultural techniques, porcelain, and artistic motifs to the Middle East, and supported the writing of histories. They also promoted Sufism in the Islamic world and influenced Russian government, trade, and art, among other impacts. Europeans became aware, via Marco Polo who traveled through the Mongols' domains, of Asian products, as well as technological, scientific, and philosophical innovations in the East and were motivated to find sea routes to South and East Asia.

• 한국기계가공학회지
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• 제20권12호
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• pp.8-15
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• 2021

Cold forging is a method in which molding is performed at room temperature. It has a high material recovery rate and dimensional precision and produces excellent surface quality, and it is mainly used for the production of bolted or housing products. The lifespan of cold forging molds is generally determined by the wear of the mold, plastic deformation of the mold, and fatigue strength. Cold forging molds are frequently damaged due to fatigue destruction rather than wear and plastic deformation in a high-temperature environment as it is molded at room temperature without preheating the raw material and mold. Based on the results analyzed through FEM, an effective mold structure design method was proposed by analyzing the changes in tensile and compressive stresses on molds according to the number of molds and reinforcement rings and comparing the product geometry and mold stress using three existing mold models.

• International Journal of Naval Architecture and Ocean Engineering
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• 제13권1호
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• pp.450-465
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• 2021

In this study, an attempt has been made to investigate the water-entry characteristics of the high-speed parallel projectile numerically. The shear stress transport k-𝜔 turbulence model and the Zwart-Gerber-Belamri cavitation model based on the Reynolds-Averaged Navier-Stokes method were used. The grid independent inspection and grid convergence index is carried out and verified. The influences of the parallel water-entry on flow filed characteristics, trajectory stability and drag reduction performance for different values of initial water-entry speed (𝜈₀ = 280 m/s, 340 m/s, 400 m/s) and clearance between the parallel projectiles (L_p = 0.5D, 1.0D, 2.0D, 3.0D) are presented and analyzed in detail. Under the condition of the parallel water-entry, it can be found that due to the intense interference between the parallel projectiles, the distribution of cavity is non-uniform and part of the projectile is exposed to water, resulting in the destruction of the cavity structure and the decline of trajectory stability. In addition, the parallel projectile suffers more severe lateral force that separates the two projectiles. The drag reduction performance is impacted and the velocity attenuation is accelerated as the clearance between the parallel projectiles reduces.