Effect of thermal annealing on the ac impedance of Co(75)/Al2O3 (2.3)/Co(5.0)/Al2O3 (2.3)/Co(50) double-barrier MTJs

Nguyen Tuan Anh,Nguyen Anh Tuan,Nguyen Tuyet Nga,Nguyen Anh Tue,Giap Van Cuong 한국물리학회 2014 Current Applied Physics Vol.14 No.10

Double-barrier magnetic tunnel junctions (DBMTJs) were prepared from Co(75 nm)/Al2O3(2.3 nm)/ Co(5 nm)/Al2O3(2.3 nm)/Co(50 nm) sputtering pentalayer films. The ac electrical properties of asdeposited DBMTJs and those annealed in a vacuum at 100e350 C for 30 min were then investigated using a complex impedance spectroscopic technique. The ac impedance responses as a function of annealing temperature were further analyzed based on Maxwell's layered dielectric barrier and Maxwell eWagner capacitor models after considering the DBMTJs as having double-capacitor-type structures. The effect of thermal annealing on the ac transport behavior of the DBMTJs was interpreted by examining the equivalent electric circuits fitted to Nyquist plots of each different sample. The effects were found to be due to changes in the structural characteristics in both bulk and interface morphologies of Co and Al2O3 layers. The structural morphology determined the different ac transport modes that occurred in the DBMTJs.

Product service systems

Tuan Anh Tran,Joon Young Park (사)한국CDE학회 2014 한국 CAD/CAM 학회 학술발표회 논문집 Vol.2014 No.2

This paper compares design methodologies for Product service systems (PSS) in terms of how they treat various PSS dimensions and design aspects through reviewing most recent works in the field. The result of comparison is used to draw a guideline for designers and developers to choose appropriate design methodologies and approaches for their specific PSS project. PSS has been researched for more than a decade and is now becoming more and more popular in academia as well as industry. Despite that fact, the adoption of PSS is still limited for its potential. One of the main reasons is that designing PSS itself is still a challenge. Designers and developers face difficulties in choosing appropriate PSS design methodologies for their projects so that they can product effective PSS offerings. By reviewing most recent works, defining PSS dimensions and design aspects, selecting criteria and scoring rules, this paper shows a clear picture of how different design methodologies can be utilized at their best in terms of application.

Separation of Text and Non-text in Document Layout Analysis using a Recursive Filter

( Tuan-anh Tran ),( In-seop Na ),( Soo-hyung Kim ) 한국인터넷정보학회 2015 KSII Transactions on Internet and Information Syst Vol.9 No.10

A separation of text and non-text elements plays an important role in document layout analysis. A number of approaches have been proposed but the quality of separation result is still limited due to the complex of the document layout. In this paper, we present an efficient method for the classification of text and non-text components in document image. It is the combination of whitespace analysis with multi-layer homogeneous regions which called recursive filter. Firstly, the input binary document is analyzed by connected components analysis and whitespace extraction. Secondly, a heuristic filter is applied to identify non-text components. After that, using statistical method, we implement the recursive filter on multi-layer homogeneous regions to identify all text and non-text elements of the binary image. Finally, all regions will be reshaped and remove noise to get the text document and non-text document. Experimental results on the ICDAR2009 page segmentation competition dataset and other datasets prove the effectiveness and superiority of proposed method.

Determination on the Technical Criteria of Materials in the Mekong Delta for the Flooded Flexible Pavement

Tuan Anh Nguyen,Tuan Thanh Pham 한국도로학회 2018 한국도로학회 학술대회 발표논문 초록집 Vol.2018 No.05

Road network in the Mekong Delta is mostly coastal and river routes, then they are often flooded when the floods come in. As a result, the foundation and pavement are destroyed, reduced life expectancy, resulting in unsafety in traffic, cost of maintenance and repairs…. This paper establishes the technical conditions for the calculation on the flexible pavement working in the wet conditions (so flooded) based on the maximum usage of available materials in the provinces in the Mekong Delta. Simultaneously, we propose the flooded flexible pavement under the current climate change conditions.

Analysis of Insulating Characteristics of Cl₂-He Mixture Gases in Gas Discharges

Tuan, Do Anh The Korean Institute of Electrical Engineers 2015 Journal of Electrical Engineering & Technology Vol.10 No.4

Insulating characteristics of Cl₂-He mixture gases in gas discharges were analysed to evaluate ability of these gases for using in medium voltage and many industries. These are electron transport coefficients, which are the electron drift velocity, density-normalized longitudinal diffusion coefficient, and density-normalized effective ionization coefficient, in Cl₂-He mixtures. A two-term approximation of the Boltzmann equation was used to calculate the electron transport coefficients for the first time over a wide range of E/N (ratio of the electric field E to the neutral number density N). The limiting field strength values of E/N, (E/N)_lim, for these binary gas mixtures were also derived and compared with those of the pure SF₆ gas.

An Improved Iterative Procedure for Outlier Detection in Time Series

Tuan Anh Bui,Chi-Hyuck Jun(전치혁) 대한산업공학회 2012 대한산업공학회지 Vol.38 No.1

We address some potential problems with the existing procedures of outlier detection in time series. Also we propose modifications in estimating model parameters and outlier effects in order to reduce the number of tests and to increase the detection accuracy. Experiments with some artificial data sets show that the proposed procedure significantly reduces the number of tests and enhances the accuracy of estimated parameters as well as the detection power.

Automatic Suggestion for PubMed Query Reformulation

Tuan, Luu Anh,Kim, Jung-Jae Korean Institute of Information Scientists and Eng 2012 Journal of Computing Science and Engineering Vol.6 No.2

Query reformulation is an interactive process of revising user queries according to the query results. To assist biomedical researchers in this process, we present novel methods for automatically generating query reformulation suggestions. While previous work on query reformulation focused on addition of words to user queries, our method can deal with three types of query reformulation (i.e., addition, removal and replacement). The accuracy of the method for the addition type is ten times better than PubMed's "Also try", while the execution time is short enough for practical use.

Molecular characterization of flavonoid biosynthetic genes and accumulation of baicalin, baicalein, and wogonin in plant and hairy root of <i>Scutellaria lateriflora</i>

Tuan, Pham Anh,Kim, Young Seon,Kim, Yeji,Thwe, Aye Aye,Li, Xiaohua,Park, Chang Ha,Lee, Sook Young,Park, Sang Un Elsevier 2018 Saudi journal of biological sciences Vol.25 No.8

<P><B>Abstract</B></P> <P> <I>Scutellaria lateriflora</I> is well known for its medical applications because of the presence of flavanoids and alkaloids. The present study aimed to explore the molecular aspects and regulations of flavanoids. Five partial cDNAs encoding genes that are involved in the flavonoid biosynthetic pathway: phenylalanine ammonia lyase (SlPAL), cinnamate 4-hydroxylase (SlC4H), 4-coumaroyl CoA ligase (Sl4CL), chalcone synthase (SlCHS), and chalcone isomerase (SlCHI) were isolated from <I>S. lateriflora</I>. Organ expression analysis showed that these genes were expressed in all organs analyzed with the highest levels correlating with the richest accumulation of wogonin in the roots. Baicalin and baicalein differentially accumulated in <I>S. lateriflora</I> plants, with the highest concentration of baicalin and baicalein detected in the leaves and stems, respectively. Exogenous methyl jasmonate (MeJA) significantly enhanced the expression of <I>SlCHS</I> and <I>SlCHI</I>, and accumulation of baicalin (22.54 mg/g), baicalein (1.24 mg/g), and wogonin (5.39 mg/g) in <I>S. lateriflora</I> hairy roots. In addition, maximum production of baicalin, baicalein, and wogonin in hairy roots treated with MeJA was approximately 7.44-, 2.38-, and 2.12-fold, respectively. Light condition increased the expression level of <I>SlCHS</I>, the first committed step in flavonoid biosynthesis in hairy roots of <I>S. lateriflora</I> after 3 and 4 weeks of development compared to the dark condition. Dark-grown hairy roots contained a higher content of baicalin and baicalein than light-grown hairy roots, while light-grown hairy roots accumulated more wogonin than dark-grown hairy roots. These results may helpful for the metabolic engineering of flavonoids biosynthesis in <I>S. lateriflora</I>.</P>

Carotenoid Accumulation and Characterization of cDNAs Encoding Phytoene Synthase and Phytoene Desaturase in Garlic (<i>Allium sativum</i>)

Tuan, Pham Anh,Kim, Jae Kwang,Kim, Haeng Hoon,Lee, Sook Young,Park, Nam Il,Park, Sang Un American Chemical Society 2011 Journal of agricultural and food chemistry Vol.59 No.10

<P>Phytoene synthase (PSY) and phytoene desaturase (PDS), which catalyze the first and second steps of the carotenoid biosynthetic pathway, respectively, are key enzymes for the accumulation of carotenoids in many plants. We isolated 2 partial cDNAs encoding PSY (<I>AsPSY-1</I> and <I>AsPSY-2</I>) and a partial cDNA encoding PDS (<I>AsPDS</I>) from <I>Allium sativum</I>. They shared high sequence identity and conserved motifs with other orthologous genes. Quantitative real-time PCR analysis was used to determine the expression levels of AsPSY1, AsPSY2, and AsPDS in the bulbils, scapes, leaves, stems, bulbs, and roots of garlic. High-performance liquid chromatography demonstrated that carotenoids were not biosynthesized in the underground organs (roots and bulbs), but were very abundant in the photosynthetic organs (leaves) of <I>A. sativum</I>. A significantly higher amount of β-carotene (73.44 μg·g<SUP>–1</SUP>) was detected in the leaves of <I>A. sativum</I> than in the other organs.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jafcau/2011/jafcau.2011.59.issue-10/jf2009827/production/images/medium/jf-2011-009827_0003.gif'></P>

Components Constituting the Audit Expectation Gap: The Vietnamese Case

Tuan Anh DANG,Dung Khanh Ngoc NGUYEN 한국유통과학회 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.1

The present study seeks to investigate the degree of awareness that constitutes the audit gap expectations (AEG) to determine which audit responsibilities can be narrowed or even eliminated. The author had surveyed a sample comprising four groups including auditors, auditees, the financial community, and other interest groups. In this survey, 1400 questionnaires were sent to the respondents, and the total number of responses was 454. The collected data was processed using statistical software SPSS, version 22. The Chi-Square test was used to analyze the effect of professional differences on AEG. The results of this study indicate that AEG cannot be eliminated due to the occupational impact of each survey group (about 46%), but it can be narrowed down to 54%, including a reduction of 11% in the knowledge gap (lack of public knowledge), 13% in the reasonable expectations gap (unqualified audit quality), 30% in the deficient standards gap (limited auditing standards). These results could be attained by improving training, communicating, and adding more responsibilities. This is the first study that provides another method of measuring the contribution of the knowledge gap through professional differences and professional gaps that make up each of the AEG’s components.