The Impact of Psychological and Environmental Factors on Consumers’ Purchase Intention toward Organic Food: Evidence from Vietnam

Dinh Toan NGUYEN,Dinh Chien TRUONG 한국유통과학회 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.1

The study investigates some psychological and environmental factors affecting the intention to purchase organic foods of consumers in the inner-city of Hanoi. Impact factors applied for the study include three psychological factors (health concern, environmental concern, consumer awareness of organic foods) and seven environment factors (family’s opinion, friends and colleagues’ opinion, influence of celebrities, expert’s opinion, social status, mass media, state’s encouragement). We analyzed research data from 396 consumers to measure the impacting level of these factors. The convenient sampling method was used to collect the research sample. The measurement applied a 5-point Likert scale classifying from 1–completely disagree to 5–completely agree. Based on previous studies, the research model was recommended. We had estimated the reliability of the scales through Cronbach’s Alpha and composite reliability. The research data is analyzed by using Structural Equation Model method (SEM). The findings of the study suggest that psychological factors (health concern, environmental concern, consumer awareness of organic foods) had a significantly positive influence on consumer’s purchase attention toward organic food. The results also revealed that environmental factors (family’s opinion, friends and colleagues’ opinion, influence of celebrities, expert’s opinion, mass media) were positively linked to consumer’s purchase attention toward organic food.

Developing Parameters of Forecasting Models in the Field of Distribution Science to Forecast Vietnamese Seafarer Resources

Dinh-Chien DANG,Thai-Duong NGUYEN,Nhu-Ty NGUYEN 한국유통과학회 2021 유통과학연구 Vol.19 No.8

Measurement Coding for Compressive Sensing of Color Images

Dinh, Khanh Quoc,Trinh, Chien Van,Nguyen, Viet Anh,Park, Younghyeon,Jeon, Byeungwoo The Institute of Electronics and Information Engin 2014 IEIE Transactions on Smart Processing & Computing Vol.3 No.1

From the perspective of reducing the sampling cost of color images at high resolution, block-based compressive sensing (CS) has attracted considerable attention as a promising alternative to conventional Nyquist/Shannon sampling. On the other hand, for storing/transmitting applications, CS requires a very efficient way of representing the measurement data in terms of data volume. This paper addresses this problem by developing a measurement-coding method with the proposed customized Huffman coding. In addition, by noting the difference in visual importance between the luma and chroma channels, this paper proposes measurement coding in YCbCr space rather than in conventional RGB color space for better rate allocation. Furthermore, as the proper use of the image property in pursuing smoothness improves the CS recovery, this paper proposes the integration of a low pass filter to the CS recovery of color images, which is the block-based ${\ell}_{20}$-norm minimization. The proposed coding scheme shows considerable gain compared to conventional measurement coding.

Compressive Sensing Recovery of Natural Images Using Smooth Residual Error Regularization

Chien Van Trinh,Khanh Quoc Dinh,Viet Anh Nguyen,Younghyeon Park(박영현),Byeungwoo Jeon(전병우) 대한전자공학회 2014 전자공학회논문지 Vol.51 No.6

압축센싱은 성긴 (sparse) 신호에 대해 Nyquist rate 미만의 샘플링으로도 신호 획득이 가능하다는 것을 수학적으로 증명한 새로운 개념이다. 그동안 영상분야 압축센싱을 위한 수많은 복원 알고리즘들이 제안되어 왔으나, 낮은 측정률 하에서는 복원 화질 측면에서 아직 개선할 점이 많다. 일례로, 자연 영상의 압축센싱 복원 화질 향상을 위해, 영상과 관련한 사전 정보들로부터 정규화 식을 도출하여 복원에 적용해 볼 수 있을 것이다. 따라서, 본 논문에서는 Dantzig selector 및 평활 필터(가우시안필터 및 nonlocal 평균 필터)기반의 평활 잔차 오류 정규화 방법을 제안한다. 또한, 복원 영상의 객체 및 배경에서 발생하는 edge 정보를 우수하게 보전하는 것으로 알려진 Total variation 기반 최소화 알고리즘에 적용하여 복원 영상의 화질을 향상시키는 방법을 제안한다. 제안하는 구조는 잔차신호의 평활화를 활용한다는 측면에서 새로운 압축센싱 복원 방식이라고 할 수 있다. 실험 결과, 제안방법은 기존 방법들에 비해 객관적 및 주관적 화질 측면에서 더 높은 성능 향상을 보여주었으며, 특히 기존 Bayesian 압축센싱 복원 방식과 비교 시 최대 9.14 dB 성능이 향상되었다. Compressive Sensing (CS) is a new signal acquisition paradigm which enables sampling under Nyquist rate for a special kind of signal called sparse signal. There are plenty of CS recovery methods but their performance are still challenging, especially at a low sub-rate. For CS recovery of natural images, regularizations exploiting some prior information can be used in order to enhance CS performance. In this context, this paper addresses improving quality of reconstructed natural images based on Dantzig selector and smooth filters (i.e., Gaussian filter and nonlocal means filter) to generate a new regularization called smooth residual error regularization. Moreover, total variation has been proved for its success in preserving edge objects and boundary of reconstructed images. Therefore, effectiveness of the proposed regularization is verified by experimenting it using augmented Lagrangian total variation minimization. This framework is considered as a new CS recovery seeking smoothness in residual images. Experimental results demonstrate significant improvement of the proposed framework over some other CS recoveries both in subjective and objective qualities. In the best case, our algorithm gains up to 9.14 dB compared with the CS recovery using Bayesian framework.

Block compressive sensing of image and video with nonlocal Lagrangian multiplier and patch-based sparse representation

Chien, T.V.,Dinh, K.Q.,Jeon, B.,Burger, M. Elsevier 2017 SIGNAL PROCESSING-IMAGE COMMUNICATION - Vol.54 No.-

<P>Although block compressive sensing (BCS) makes it tractable to sense large-sized images and video, its recovery performance has yet to be significantly improved because its recovered images or video usually suffer from blurred edges, loss of details, and high-frequency oscillatory artifacts, especially at a low subrate. This paper addresses these problems by designing a modified total variation technique that employs multi-block gradient processing, a denoised Lagrangian multiplier, and patch-based sparse representation. In the case of video, the proposed recovery method is able to exploit both spatial and temporal similarities. Simulation results confirm the improved performance of the proposed method for compressive sensing of images and video in terms of both objective and subjective qualities.</P>

Effects of porosity and thermomechanical loading on free vibration and nonlinear dynamic response of functionally graded sandwich shells with double curvature

Trinh, Minh-Chien,Nguyen, Dinh-Duc,Kim, Seung-Eock Elsevier 2019 Aerospace science and technology Vol.87 No.-

<P><B>Résumé</B></P> <P>The fundamental frequencies and nonlinear dynamic responses of functionally graded sandwich shells with double curvature under the influence of thermomechanical loadings and porosities are investigated in this study. Two material models are considered. The continuity requirement of material properties throughout layers are fulfilled by newly introducing refined effects of two porosity types regarding the average of constituent properties weighted by the porosity volume fraction. The first-order shear deformation theory taking the out-of-plane shear deformation into account is employed to obtain the Lagrange equation of motions. The number of primary variables reduces from five to three after introducing the Airy stress function. The system of dynamic governing equations is obtained by utilizing the Bubnov–Galerkin procedure. The natural frequencies are analytically computed by solving eigenvalue problems, and the fundamental frequencies are acquired by further assumptions about the inertial force caused by the shell rotation variables. The nonlinear dynamic responses of the functionally graded spherical, cylindrical, and hyperbolic paraboloid shells under the influence of different geometry configurations, loading conditions, and porosity types and degrees are obtained by applying the fourth-order Runge–Kutta method. The numerical results are presented and verified with available studies in the literature. Although porosities are usually considered material defects weakening the structure performance, this study has proved clearly that porosities stiffen the shell structures to some extent.</P>

Miniaturized Capacitively Loaded Step-Impedance Bandpass Filter in Multilayer Substrate

Thai Hoa, Duong,Dinh Chien, Hoang,Kim, Ihn Seok 慶熙大學校 레이저 工學硏究所 2007 레이저공학 Vol.18 No.-

In this paper, a miniaturized low insertion loss interdigital bandpass filter with capacitively loaded stepped impedance resonators (SIR) in Low Temperature Co-fired Ceramic (LTCC) technology is introduced. By using SIR and capacitive loading structures based on 6_(r) = 41.77 substrates, a wideband interdigital bandpass filter has been realized for the frequency range from 3.1 GHz to 4.8 GHz. Measurement shows insertion loss less than 0.8 dB, return loss better than 15 dB in the pass band with the center frequency at 3.95 GIIz and bandwidth ratio of 43 %. The filter has a size of 2.15 × 2.6 × 0.85㎣.

Detection of pathogenic microorganisms using biosensor based on multi-walled carbon nanotubes dispersed in DNA solution

Nguyen Thi Thuy,Phuong Dinh Tam,Mai Anh Tuan,Anh-Tuan Le,Le Thi Tam,Vu Van Thu,Nguyen Van Hieu,Nguyen Duc Chien 한국물리학회 2012 Current Applied Physics Vol.12 No.6

The present paper introduces a facile and cost-effective route for the direct dispersion of multi-walled carbon nanotubes (MWCNTs) in DNA solution. Their application in detecting Escherichia coli O157:H7using DNA biosensorwas demonstrated. The dispersion state of theMWCNTswas characterized via UVeVis spectroscopy, transmission electron microscopy, and field emission scanning electron microscopy. The interaction between DNA sequence and the MWCNTs was investigated using Raman spectroscopy and Fourier transform infrared spectroscopy. As-obtainedMWCNT solutionwas used in the preparation of DNA sensor. Results revealed that the developed DNA sensor can detect a DNA target as low as 1 nM in a buffer solution. The sensitivity of the DNA sensor reached approximately 0.19 nM/mV. The effect of dispersion parameters, including pH values, DNA concentration, ion strength, and sonication time, on sensor response was also studied. TheDNA sensor can respondwell to 120 min of sonication time, a pH value of 9, and 20 mM of DNA sequence concentration. The results of the present study showed a potential application of the DNA sensor in the detection of Escherichia coli O157:H7.

Block-Based Transform-Domain Measurement Coding for Compressive Sensing of Images

Quang Hong Nguyen,Viet Anh Nguyen,Chien Van Trinh,Khanh Quoc Dinh,Younghyeon Park(박영현),Byeungwoo Jeon(전병우) 한국통신학회 2014 韓國通信學會論文誌 Vol.39 No.12(통신이론)

A Skip-mode Coding for Distributed Compressive Video Sensing

Quang Hong Nguyen,Khanh Quoc Dinh,Viet Anh Nguyen,Chien Van Trinh,Younghyeon Park(박영현),Byeungwoo Jeon(전병우) 한국방송·미디어공학회 2014 방송공학회논문지 Vol.19 No.2

Distributed compressive video sensing (DCVS) is a low cost sampling paradigm for video coding based on the compressive sensing and the distributed video coding. In this paper, we propose using a skip-mode coding in DCVS under the assumption that in case of high temporal correlation, temporal interpolation can guarantee sufficiently good quality of nonkey frame, therefore no need to transmit measurement data in such a nonkey frame. Furthermore, we extend it to use a hierarchical structure for better temporal interpolation. Simulation results show that the proposed skip-mode coding can save the average subrate of whole video sequence while the PSNR is reduced only slightly. In addition, by using the proposed scheme, the computational complexity is also highly decreased at decoder on average by 43.75% for video sequences that have strong temporal correlation.