A New Algorithm for Silhouette Detection in Volume Objects and Its Parallelization

Chin, H.,Ramakrishna, R. S. INSTITUTE OF ELECTRONICS, INFORMATION 2005 IEICE transactions on information and systems Vol.88 No.8

Adsorption/desorption kinetics of nitric oxide on zinc oxide nano film sensor enhanced by light irradiation and gold-nanoparticles decoration

Chinh, Nguyen Duc,Hien, Truong Thi,Do Van, Lam,Hieu, Nguyen Minh,Quang, Nguyen Duc,Lee, Seung-Mo,Kim, Chunjoong,Kim, Dojin Elsevier 2019 Sensors and actuators. B, Chemical Vol.281 No.-

<P><B>Abstract</B></P> <P>ZnO thin-films with precisely controlled thicknesses were fabricated by the atomic layer deposition and their <I>NO</I> gas sensing properties were investigated at different temperatures, and in particular, under light irradiation of various energy and intensity at room temperature with and without Au catalyst. The molecular dynamics of <I>NO</I> and <I>O</I> <SUB>2</SUB> during the response and recovery cycles in relation with the <I>NO</I> sensing performance in air environment was elaborated using the energy diagram modelled for adsorption and desorption kinetics of the gas molecules. The blue light irradiation combined with Au catalytic effect greatly enhanced the <I>NO</I> response rate, but delayed the recovery rate in the air environment via molecular dynamic interference from the environmental oxygen. The optimum condition for <I>NO</I> sensing was obtained for the film thickness, light energy and intensity. Critical issues for the stable sensor operation such as concentration dependence, gas selectivity, and humidity effect were also reported.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Gas sensing response/recovery kinetics of NO sensing by ZnO with light irradiation and Au catalytic effect at room temperature. </LI> <LI> Molecular dynamics consideration for adsorption and desorption to explain the detection of ppm level gas concentrations. </LI> <LI> The nano-effect in varying thicknesses of ZnO. </LI> </UL> </P>

Relatives' Hospitalizated Cerebrovascular Accident Patients

Chinh Thi Minh Nguyen 한국간호과학회 2011 한국간호과학회 학술대회 Vol.2011 No.10

Exploration of Essential Structure of Malloapelta B for the Inhibitory Activity Against TNF Induced NF-κB Activation

Chinh Van Luu,Minh Van Chau,Jung-Joon Lee,Sang-Hun Jung 대한약학회 2006 Archives of Pharmacal Research Vol.29 No.10

For the exploration of pharmacophoric moiety of malloapelta B (1) possessing the inhibitory activity of NF-κB activation, structural variation of α,β-unsaturated carbonyl motif was attempted. 1 was reduced by catalytic hydrogenation, sodium borohydride, and lithium aluminumhydride. Catalytic hydrogenation with 30 psi or 15 psi of H2 gas of 1 generated 8-butyl–5,7- dimethoxy-2,2-dimethylchroman (2) and 1-(5,7-dimethoxy-2,2-dimethylchroman-8-yl)butan-1- one (3), respectively. Reduction with sodium borohydride occurred at the double bond of α,β- unsaturated ketone of 1 to give 1-(5,7-dimethoxy-2,2-dimethyl-2H-chromen-8-yl)butan-1-one (4). Reduction of 1 with lithium aluminumhydride and then quenched with methanol and water produced unexpected products, 1-(5,7-dimethoxy-2,2-dimethyl-2H-chromen-8-yl)-3-methoxy-1- butene (5) and 1-(5,7-dimethoxy-2,2-dimethyl-2H-chromen-8-yl)-3-hydroxy-1-butene (6). These are formed from the isomerization of initial product 9 through the continuous conjugate carbocation intermediate 11. Addition of ethylmagnesium bromide and dimethyl malonate anion to 1 gave the conjugate adducts 7 and 8. Ethylmagesium bromide and sodium borohydride reduction unusually gave the conjugate addition due to steric congestion around carbonyl group of 1. Compound 2 exhibits the reduced inhibitory activity against NF-κB activation and the others do not show the activity. Therefore α,β-unsaturated carbonyl group of 1 should be important for its inhibitory activity.

Stress and Surface Tension Analyses of Water on Graphene-Coated Copper Surfaces

Chinh Thanh Nguyen,김보흥 한국정밀공학회 2016 International Journal of Precision Engineering and Vol.17 No.4

Graphene-coated materials have recently emerged as promising materials for green renewable energy applications due to the benefits of combining graphene and metals. For these types of composites, the effect of graphene coating on the wettability of metal substrates has attracted much attention from researchers. In this paper, a series of molecular dynamics simulations, in which water droplets are deposited on bare Cu (111) and graphene-coated Cu (111), were conducted to investigate the influences of graphene coating on the wettability of copper. We found that water contact angles gradually increased and converged to the value measured on pure graphite surfaces as the number of graphene layers deposited on the Cu (111) surface increased. The “wetting transparency of graphene was proven to break down as demonstrated by the fact that the water contact angle of mono-layer graphene-coated copper was found to significantly increase as compared to that of bare copper. Density and stress profiles of water droplets were examined to confirm the effect of the number of graphene layers on copper-water interactions. We also examined the surface tensions of water droplets on graphene-coated copper substrates. We found that the liquid-vapor and solid-vapor surface tensions are constant while the solidliquid tension varies with the graphene coating; this leads to the variation in the water droplet contact angles.

UV-light-activated H₂S gas sensing by a TiO₂ nanoparticulate thin film at room temperature

Chinh, Nguyen Duc,Kim, Chunjoong,Kim, Dojin Elsevier 2019 Journal of Alloys and Compounds Vol.778 No.-

<P><B>Abstract</B></P> <P>A UV-light-activated TiO<SUB>2</SUB> thin film gas sensor composed of nanoparticles is reported for H<SUB>2</SUB>S detection at room temperature. TiO<SUB>2</SUB> nanoparticulate thin films were fabricated by bar coating of a mixture of TiO<SUB>2</SUB> powder and acetic acid. The morphology and structural properties of the films were examined by scanning electron microscopy, X-ray diffraction, photoluminescence spectroscopy, and absorption spectroscopy. The nil response to H<SUB>2</SUB>S was significantly enhanced by UV light irradiation in the response levels and response/recovery kinetics. The effect of the sensor conductance and light intensity towards sensor optimization was discussed. The sensor exhibited high gas selectivity, repeatability, and linearity for practical applications of the sensor, but the interference of humidity on the sensing process needs to be solved. The results exhibited a simple way to detect parts per million concentrations of H<SUB>2</SUB>S at room temperature.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Nanoparticulate TiO<SUB>2</SUB> thin film was fabricated by a cost-effective method of bar coating. </LI> <LI> H<SUB>2</SUB>S sensing at room temperature under UV irradiation satisfying the sensor. </LI> <LI> Analysis of the response-recovery kinetics under UV irradiation at RT. </LI> </UL> </P>

Versatile Double Metal Cyanide Catalysts for Organic Reactions

Chinh Hoang Tran,문병렬,김일 한국고분자학회 2022 한국고분자학회 학술대회 연구논문 초록집 Vol.47 No.1

Synthesis of Branched Polycarbonate Polyols via Ring-Opening Multibranching Copolymerization of Glycidol and CO₂

Hoang Chinh Tran,김일 한국고분자학회 2023 한국고분자학회 학술대회 연구논문 초록집 Vol.48 No.1

A Study on the Structural Changes of Cashew Nut’s Global Trade Network: Focused on Vietnam

Thi Chinh Vo,Seong-Tae Ji 한국무역연구원 2021 무역연구 Vol.17 No.1

Purpose This paper aims to analyze the structural changes of cashew nut’s global trade network due to changes in the supply and demand of cashew nuts in Vietnam using the degree centrality index and visualizing them. Design/Methodology/Approach This paper analyzes the global cashew nut trade network based on the Degree Centrality;Betweenness Centrality;and Closeness Centrality indexes of Social Network Analysis. The 2000-2009 trade data from the UN Comtrade database was used;and the 2000-2009 and 2010-2019 data were analyzed separately;assuming that Vietnam’s cashew nuts production structure changed around 2010. Findings With Vietnam’s recent decline in cashew nuts production;Vietnam’s index (weighted) was the largest in the in-shell cashews In-degree Centrality and the shelled cashews Out-degree Centrality analysis in 2010-2019. It means that Vietnam’s influence in the global cashew nuts network has been increased compared to that in 2000-2009 due to increased trade volume and partner countries. Moreover;Betweenness Centrality and Closeness Centrality index shows that Vietnam’s ability to control the flow of cashew nuts exports and imports and its ability to adapt and react to changes in the global cashews market has been enhanced compared to the past. Research Implications Vietnam was the world’s largest producer of cashew nuts;processing and exporting its domestic produced cashew nuts. However;with the recent decline in domestic production;in-shell cashew nuts have been imported from African countries such as Côte d’Ivoire. So;a new global food value chain was formed by processing and exporting them. It means a change in Vietnam’s cashew nuts industry structure and a new South-South cooperation model in the agricultural sector. In other words;developing countries can form a global value chain in the agricultural sector and be mutually win-win.

Soft Power of Korean Culture in Vietnam and its Effects

Dinh Chinh Le 인하대학교 다문화융합연구소 2016 다문화와 교육 Vol.1 No.1

As Asian countries, Vietnam and Korea have many similarities in history and culture. For many years, those two countries has had a cooperative relations. Especially, the interests in Korean culture of Vietnamese people were huge. Overall, Hallyu, the Korean cultural wave has been received by the Vietnamese people through various pathways including education and training. Regarding pathway of scientific researches, many international scientific conferences related to Korean and Korean studies was held in Vietnam such as Film and TV, music, tourism, oversea study, Vietnamese workers working in Korean companies, and Korea–Vietnam multicultural family. In the past two decades, with many different communication channels, Hanllyu played an important role in promoting Korean effects in Vietnam. This study analysis both positive and negative effects. Therefore, besides the acquisitions of external cultural essence, we always respect, preserve and promote traditional cultural identity of our peoples that has been crystallized through thousands of years.