The Effect of Country-of-Origin on Customer Purchase Intention: A Study of Functional Products in Vietnam

Nguyen,Ngoc Duy Phuong,Nguyen,Tien Dat 한국유통과학회 2019 KODISA ICBE (International Conference on Business Vol.2019 No.-

This paper examines key determinants and the effect of country-of-origin on customer’s purchase intention of functional food and dietary supplement product in Vietnam. Data was collected from a survey of 242 Vietnamese who have experienced in buying functional and supplement food. This paper employed partial least square (PLS) as a technique used to analyze the measurement and structural models. The findings provide evidence that social prestige customer perceives and their positive attitude toward functional food which are main factors influencing on consumers’ purchase intention. Customer’s perceived prestige plays an important role in decision-making process to purchase. The higher social prestige taken up in consumers’ mind, the higher consumers’ purchase intention is. Moreover, the more positive attitude customer holds toward functional food, the higher consumers’ purchase intention. The research results provide useful information in current understanding of what antecedents determine factors influencing customer’s intention to purchase functional food and lead to managerial implications for business strategies.

New Inhibitor against Nuclear Factor of Activated T Cells Transcription from <i>Ribes fasciculatum</i> var. <i>chinense</i>

Dat, Nguyen Tien,Cai, Xing Fu,Shen, Quanghai,Lee, Im Seon,Kim, Young Ho The Pharmaceutical Society of Japan 2005 Chemical & pharmaceutical bulletin Vol.53 No.1

<P>Two new compounds were isolated from the stem and twigs of <I>Ribes fasciculatum</I> var. <I>chinense</I> and their structures were identified to be <I>threo</I>-(7<I>S</I>,8<I>R</I>)-1-(4-hydroxyphenyl)-2-[4-(<I>E</I>)-propenylphenoxy]-propan-1-ol (1), and 5,4′-dihydroxy-7-methoxyflavone-3-<I>O</I>-[α-<SMALL>L</SMALL>-rhamnopyranosyl(1→3)-<I>O</I>-α-<SMALL>L</SMALL>-rhamnopyranosyl(1→6)-<I>O</I>-β-<SMALL>D</SMALL>-glucopyranoside] (2). With nine other known components, they were tested on inhibitory activity against nuclear factor of activated T cells (NFAT) transcription factor. Compound 1 showed a potent inhibitory activity (IC<SUB>50</SUB>=15.6 μ<SMALL>M</SMALL>), while compounds 4, 5 and 9 showed moderate inhibitory activity (IC<SUB>50</SUB> 22.4, 24.5 and 25.7 μ<SMALL>M</SMALL>, respectively).</P>

Optically Transparent Patch Antennas Using Saltwater for WLAN Applications

Nguyen Tien Dat,최정한,정창원 한국전자파학회 2022 Journal of Electromagnetic Engineering and Science Vol.22 No.6

This paper presents the design, fabrication, and measurement of a novel transparent patch antenna using saltwater with high-opticaltransparency applications for wireless local area networks (WLANs) at 2.4–2.5 GHz. The most important reason for using saltwater for transparent antenna applications is its superior average optical transparency (OTav >90%) compared to other typical transparent electrodes, such as indium tin oxide (ITO; OTav >80%) or metal-mesh film (MMF; OTav >60%). This study designs three types of antennas: an antenna with a conductive part made of copper sheet (CS) for both the radiator and ground plane (case 1) to compare the performance with two types of proposed transparent antennas that use saltwater as the conductive parts; an antenna with saltwater for the radiator and MMF for the ground plane (case 2); and an antenna with saltwater for both the radiator and ground plane (case 3). The case 1, case 2, and case 3 antennas have peak gains of 6.87, 4.4, and 1.91 dB, respectively, and have corresponding radiation efficiencies of 93.5%, 62%, and 34%. To the best of our knowledge, this is the first demonstration of a transparent patch antenna using saltwater.

The Inhibition of Diacylglycerol Acyltransferase by Terpenoids from Youngia koidzumiana

Dat Nguyen Tien,Cai Xing Fu,Rho Mun-Chual,Lee Hyun Sun,Bae KiHwan,Kim Young Ho The Pharmaceutical Society of Korea 2005 Archives of Pharmacal Research Vol.28 No.2

The EtOAc extract of Youngia koidzumiana significantly inhibited the diacylglycerol acyltransferase (DGAT) from rat liver microsomes. Bioactivity-guided fractionation led to the isolation of nine compounds, the structures of which were established using physicochemical and spectral data. Of the isolated compounds, oleanolic acid (2), methyl ursolate (7) and corosolic aicd (8) inhibited DGAT, with $IC_{50}$ values of 31.7, 26.4, and $44.3{\mu}M$, respectively. However, sesquit-erpenoids showed only weak inhibitory effects toward DGAT.

The Inhibition of Diacylglycerol Acyltransferase by Terpenoids from Youngia koidzumiana

Nguyen Tien Dat,Xing Fu Cai,노문철,이현선,배기환,김영호 대한약학회 2005 Archives of Pharmacal Research Vol.28 No.2

The EtOAc extract of Youngia koidzumiana significantly inhibited the diacylglycerol acyltransferase (DGAT) from rat liver microsomes. Bioactivity-guided fractionation led to the isolation of nine compounds, the structures of which were established using physicochemical and spectral data. Of the isolated compounds, oleanolic acid (2), methyl ursolate (7) and corosolic aicd (8) inhibited DGAT, with IC50 values of 31.7, 26.4, and 44.3 µM, respectively. However, sesquiterpenoids showed only weak inhibitory effects toward DGAT.

New Finger-vein Recognition Method Based on Image Quality Assessment

( Dat Tien Nguyen ),( Young Ho Park ),( Kwang Yong Shin ),( Kang Ryoung Park ) 한국인터넷정보학회 2013 KSII Transactions on Internet and Information Syst Vol.7 No.2

The performance of finger-vein recognition methods is limited by camera optical defocusing, the light-scattering effect of skin, and individual variations in the skin depth, density, and thickness of vascular patterns. Consequently, all of these factors may affect the image quality, but few studies have conducted quality assessments of finger-vein images. Therefore, we developed a new finger-vein recognition method based on image quality assessment. This research is novel compared with previous methods in four respects. First, the vertical cross-sectional profiles are extracted to detect the approximate positions of vein regions in a given finger-vein image. Second, the accurate positions of the vein regions are detected by checking the depth of the vein`s profile using various depth thresholds. Third, the quality of the finger-vein image is measured by using the number of detected vein points in relation to the depth thresholds, which allows individual variations of vein density to be considered for quality assessment. Fourth, by assessing the quality of input finger-vein images, inferior-quality images are not used for recognition, thereby enhancing the accuracy of finger-vein recognition. Experiments confirmed that the performance of finger-vein recognition systems that incorporated the proposed quality assessment method was superior to that of previous methods.

Gymnastone, A New Benzofuran Derivative from Gymnaster koraiensis

Dat, Nguyen-Tien,Kiem, Phan-Van,Cai, Xing-Fu,Shen, Quanghai,Bae, Ki-Hwan,Kim, Young-Ho The Pharmaceutical Society of Korea 2004 Archives of Pharmacal Research Vol.27 No.11

A new benzofuran derivative, named gymnastone [5-hydroxy-6-acetyl-2-(2-propane-1,2,3-triol)-benzofuran (1)], was isolated from the aerial part of Gymnaster koraiensis, together with viscidone (2) by repeated column chromatography. The structures of both compounds were identified by physico-chemical and spectral analysis including COSY, HMQC, and HMBC experiments.

Comparative Study of Human Age Estimation with or without Preclassification of Gender and Facial Expression

Nguyen, Dat Tien,Cho, So Ra,Shin, Kwang Yong,Bang, Jae Won,Park, Kang Ryoung Hindawi Publishing Corporation 2014 The Scientific World Journal Vol.2014 No.-

<P>Age estimation has many useful applications, such as age-based face classification, finding lost children, surveillance monitoring, and face recognition invariant to age progression. Among many factors affecting age estimation accuracy, gender and facial expression can have negative effects. In our research, the effects of gender and facial expression on age estimation using support vector regression (SVR) method are investigated. Our research is novel in the following four ways. First, the accuracies of age estimation using a single-level local binary pattern (LBP) and a multilevel LBP (MLBP) are compared, and MLBP shows better performance as an extractor of texture features globally. Second, we compare the accuracies of age estimation using global features extracted by MLBP, local features extracted by Gabor filtering, and the combination of the two methods. Results show that the third approach is the most accurate. Third, the accuracies of age estimation with and without preclassification of facial expression are compared and analyzed. Fourth, those with and without preclassification of gender are compared and analyzed. The experimental results show the effectiveness of gender preclassification in age estimation.</P>

Transparent and Flexible Patch Antenna Using MMF for Conformal Wi-Fi 6E Application

Tien Dat Nguyen,이용근,정창원 한국전자파학회 2023 Journal of Electromagnetic Engineering and Science Vol.23 No.4

In this paper, a patch antenna with compact, flexible, and transparent properties is presented to support Wi-Fi 6E (2.4 GHz/6 GHz) applications. This antenna design was formulated based on a transparent metal mesh film (MMF), for which the average optical transparency ( ) is 69% and the sheet resistance ( ) is 0.1 Ω/sq. The measurement results on frequency bands of 2.4–2.51 GHz and 5.87–7.04 GHz show that the average gain exceeds 5.4 dBi and 6.3 dBi with corresponding radiation efficiency rates as high as 67.8% and 70%. In addition, for the purpose of integration into aesthetic devices for smart home applications, the antenna conformed to foam and a lamp. All research outcomes here indicate that the proposed antenna maintains a directional radiation pattern, as well as transparency and flexibility, making it a potential candidate for transparent Internet-of-Things applications.

Compact, Flexible and Transparent Antenna Using MMF for Conformal Wi-Fi 7 Applications

Nguyen Tien Dat,Kim Sarah Eunkyung,Jung Chang Won 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.6

A compact, flexible, and transparent monopole antenna is presented for the next generation of Wi-Fi 7 technology, specifically its potential properties, such as faster transmission speeds by threefold, much higher capacity, and even lower latency. The antenna design is formulated based on a transparent metal mesh film (MMF), which has optical transparency (average of 73%) and low sheet resistance (average of 0.2 Ω/sq). To enhance the features of MMF simultaneously, the antenna is fabricated using a hybrid process that includes ultra-precise components of photolithography and electronic forming technology. The measurement results for the frequency ranges of 2.4–2.5 and 5–7.125 GHz (Wi-Fi 7 bands) show that the peak gains exceed 1.98 dBi and 3.7 dBi and that the radiation efficiency rates are 93% and 94%, respectively. Furthermore, the proposed antenna is flexible and can be bent and integrated into aesthetic devices for smart home applications. Therefore, the antenna was conformed onto foam and a lamp as examples for testing. All of the results here demonstrate that the proposed design maintains an omnidirectional radiation pattern and offers a compact, flexible solution. This makes it a good candidate for straightforward integration with transparent Internet of Things applications.