Fabrication of Planar Waveguide Chip for Splitting or Combining an Infrared Light Beam

Nguyen Thanh Binh,Nguyen Tat Thanh,Duong Thanh Trung,Nguyen Thanh Huong,Le Quoc Minh 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.52 No.5

Based on hybrid materials of polymethamethyl acrylat, silica and zirconia (ASZ)/Titania (AST), some planar structures of optical power splitter/combiner type 1×N channels were designed and simulated for making masks by using computer software. Splitter chips were then fabricated by using the thin-film sol-gel technique and their structure was formed by using a direct photo-patterning method with UV light and a mask. A conformation of the waveguide was tested with an Alpha-Step IQ system. The waveguide properties of the splitter were measured with a 1550 nm laser source. The experimental results show that the light was transmitted through the chip with a total output efficiency of around 6% and was separated uniformly at the output channels. Based on hybrid materials of polymethamethyl acrylat, silica and zirconia (ASZ)/Titania (AST), some planar structures of optical power splitter/combiner type 1×N channels were designed and simulated for making masks by using computer software. Splitter chips were then fabricated by using the thin-film sol-gel technique and their structure was formed by using a direct photo-patterning method with UV light and a mask. A conformation of the waveguide was tested with an Alpha-Step IQ system. The waveguide properties of the splitter were measured with a 1550 nm laser source. The experimental results show that the light was transmitted through the chip with a total output efficiency of around 6% and was separated uniformly at the output channels.

Development of label-free electrochemical lactose biosensor based on graphene/poly(1,5-diaminonaphthalene) film

Binh Hai Nguyen,Binh Thanh Nguyen,Hanh Van Vu,Chuc Van Nguyen,Dzung Tuan Nguyen,Loc Thai Nguyen,Thu Thi Vu,Lam Dai Tran 한국물리학회 2016 Current Applied Physics Vol.16 No.2

In this work, a lactose biosensor was developed by co-immobilizing b-galactosidase (b-Gal) and glucose oxidase (GOx) on microelectrodes pre-modified with Pt/graphene/P(1,5-DAN) for estimation of lactose in dairy products to prevent lactose intolerance. The Pt microelectrode was modified with graphene and 1,5-polydiaminonaphthalene film. Graphene was synthesized by chemical vapor deposition on copper tape and manually transferred to the electrode surface. Polymeric P(1,5-DAN) was grafted on top of the graphene film by electropolymerization. Modified surface of the electrode was characterized by Raman spectra analysis, FE-SEM, AFM and cyclic voltammetry. The results indicated that deposition graphene film on electrode surface induced considerable enhancement in current signal, over 20 times as high as the uncoated electrode surface. The developed sensor was successfully used to determine lactose in model samples with sensitivity, correlation coefficient (R2) and limit of detection (LOD) estimated to be 1.33 mA/(mgml1), 0.995 and 1.3 mg/ml, respectively. The combined graphene and conductive P(1,5-DAN) could serve as a novel sensing platform on electrochemical sensors with superior sensitivity.

Trends in prediabetes and diabetes prevalence and associated risk factors in Vietnamese adults

That Thanh Ton,Anh Thi Ngoc Tran,Ich Thanh Do,Hoa Nguyen,Thi Thanh Binh Nguyen,Minh Tu Nguyen,Van Anh Bao Ha,Anh Quoc Tran,Huu Khoi Hoang,Binh Thang Tran 한국역학회 2020 Epidemiology and Health Vol.42 No.-

OBJECTIVES: The prevalence of diabetes mellitus is rapidly increasing in Vietnam, particularly among adults aged over 45 years. This study estimated trends in diabetes and prediabetes prevalence and determined risk factors in Vietnamese adults (over 45 years). METHODS: A cross-sectional study was conducted based on data from an annual diabetes screening program among people aged 45-69 years in an urban city in central Vietnam (Da Nang). Joinpoint regression analyses were performed to calculate the annual percentage change and ptrend-values. Multinomial logistic regression analysis was used to determine risk factors. RESULTS: In total, 3,765 men and 9,149 women were included in this analysis. The age-adjusted prevalence of diabetes and prediabetes in 2017 was 11.4% and 52.9%, respectively. The prevalence of diabetes was higher in men (15.1%) than in women (10.3%), but that of prediabetes was similar in both genders (53.4% vs. 52.8%). The prevalence of prediabetes significantly increased during the study period, whereas no upward or downward trend for diabetes was observed. The prevalence of obesity, abdominal obesity, hypertension, and dyslipidemia showed no obvious trend. Obesity, a high waist-to-hip ratio, hypertension, more severe abdominal obesity, and dyslipidemia were significantly associated with a higher risk of diabetes and prediabetes. CONCLUSIONS: Diabetes and prediabetes were more prevalent among people aged over 45 years than in the general population. Da Nang has experienced a marked increase in the prevalence of prediabetes. These findings have significant implications regarding the need for nationwide public health interventions and management aiming at diabetes prevention and control.

Factors Affecting Enterprise's Satisfaction toward Social Security's Online Public Service: The Case of Thanh Hoa Province, Vietnam

NGO, Chi Thanh,NGUYEN, Thi Ngoc Mai,NGUYEN, Duy Dat,LE, Hoang Ba Huyen,LE, Van Cuong,LE, Thi Binh Korea Distribution Science Association 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.9

The study aims to investigate factors affecting enterprise's satisfaction and loyalty toward the Social Security's online public services, looking at the case of Thanh Hoa province, Vietnam. This study employs samples with 216 enterprises that use online public system of Thanh Hoa province's Social Security. The research model is closely linked to the SERVQUAL model developed by Parasuraman, Zeithaml and Berry (1988). We propose 23 scales that constitute the quality of service, three scales that constitute Customer Satisfaction and three components that constitute Customer Loyalty. This study use the tool of Exploratory Factor Analysis (EFA), Cronbach's Alpha test, Confirm Factor Analysis (CFA) and Structural Equation Modeling (SEM) in order to address the question of satisfaction and loyalty. The result shows that the factor with the most impact is Reliability, next is Capacity of staffs, Tangibles, Attitude of staffs, and the least impacting factor is Empathy; moreover, the results also show that Satisfaction has a strong impact on Customer Loyalty. The findings of this study suggest that Thanh Hoa province's Social Security should: (i) strengthen the reliability of online service system; (ii) build capacity for staffs; (iii) develop the responsiveness of electronic transactions systems; and (iv) improve the empathy of staffs.

An Effective Moving Object Detection Method for Omnidirectional Camera

Thanh Binh Nguyen,Sun Tae Chung,HoSeok Kang,Seongwon Cho,Taein Seol 한국통신학회 2013 한국통신학회 학술대회논문집 Vol.2013 No.6

Synthesis and High Photocatalytic Activity of Zn-doped TiO₂ Nanoparticles by Sol-gel and Ammonia-Evaporation Method

Nguyen, Thanh Binh,Hwang, Moon-Jin,Ryu, Kwang-Sun Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.1

Photocatalysis has been applied to decompose the waste and toxic materials produced in daily life and in the global environment. Pure $TiO_2$ (Zn-$TiO_2$-0) and Zn-doped $TiO_2$ (Zn-$TiO_2$-x, x = 3-10 mol %) samples were synthesized using a novel sol-gel and ammonia-evaporation method. The Zn-doped $TiO_2$ samples showed high photocatalytic activity for the degradation of methylene blue (MB). The physicochemical properties of the samples were investigated using XRD, SEM, ICP, DLS and BET methods. In addition, the most important measurement of photocatalytic ability was investigated by a UV-vis spectrophotometer. The effects of the mol % of zinc ion doping in $TiO_2$ on photocatalytic activity were studied. Among the mol % Zn ions investigated, the Zn-$TiO_2$-9 sample showed the highest photoreactivity. This sample removed 91.4% of the MB after 4 h, while the pure $TiO_2$ only removed 46.4% of the MB.

Real-time Human Detection under Omni-dir ectional Camera based on CNN with Unified Detection and AGMM for Visual Surveillance

Nguyen, Thanh Binh,Nguyen, Van Tuan,Chung, Sun-Tae,Cho, Seongwon Korea Multimedia Society 2016 멀티미디어학회논문지 Vol.19 No.8

In this paper, we propose a new real-time human detection under omni-directional cameras for visual surveillance purpose, based on CNN with unified detection and AGMM. Compared to CNN-based state-of-the-art object detection methods. YOLO model-based object detection method boasts of very fast object detection, but with less accuracy. The proposed method adapts the unified detecting CNN of YOLO model so as to be intensified by the additional foreground contextual information obtained from pre-stage AGMM. Increased computational time incurred by additional AGMM processing is compensated by speed-up gain obtained from utilizing 2-D input data consisting of grey-level image data and foreground context information instead of 3-D color input data. Through various experiments, it is shown that the proposed method performs better with respect to accuracy and more robust to environment changes than YOLO model-based human detection method, but with the similar processing speeds to that of YOLO model-based one. Thus, it can be successfully employed for embedded surveillance application.

Effects of hydrophobicity and lubricant characteristics on anti-icing performance of slippery lubricant-infused porous surfaces

Thanh-Binh Nguyen,박승철,정영도,임현의 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.69 No.-

Anti-icing properties were investigated in terms of adhesion force on slippery lubricant-infused porous surfaces with several lubricants. Initial wetting state of substrate and lubricant characteristics were verified in anti-icing performance. Superhydrophobicity of porous substrate under lubricant intervening layer was effective to reduce adhesion force in anti-icing. The relationships between adhesion force and lubricant characteristics including viscosity, density, and surface tension were analyzed but no correlation was found. Interfacial surface tension exhibited a relatively negative correlation with adhesion strength. However, spreading coefficient of liquid–liquid interface was found to be the most important factor in determining lubricant when designing icephobic surfaces.

An Adaptive Backstepping Trajectory Tracking Control of a Tractor Trailer Wheeled Mobile Robot

NGUYEN THANH BINH,Nguyen Anh Tung,Dao Phuong Nam,Nguyen Hong Quang 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.2

The considered Tractor Trailer Wheeled Mobile Robot (TTWMR) is type of Mobile Robot including amaster robot – Tractor and slave robots – Trailers which moves along Tractor to track a given desired trajectory. Themain difficulties of the stabilization and the tracking control of TTWMR are due to nonlinear and underactuatedsystems subjected to nonholonomic constraints. In order to overcome these problems, firstly, we develop the modelof TTWMR and transform the tracking error model to the triangular form to propose a control law and an adaptivelaw. Secondly, the varying time state feedback controllers are designed to generate actuator torques by usingBackstepping technique and Lyapunov direct’s method, in that these are able to guarantee the stability of the wholesystem including kinematics and dynamics. In addition, the Babarlat’s lemma is used to prove that the proposedtracking errors converge to the origin and the proposed adaptive law is carried on to tackle unknown parameterproblem. The simulations are implemented to demonstrate the effective performances of the proposed adaptive lawand the proposed control law.

Real-time Human Detection under Omni-directional Camera based on CNN with Unified Detection and AGMM for Visual Surveillance

Thanh Binh Nguyen,Van Tuan Nguyen,정선태,조성원 한국멀티미디어학회 2016 멀티미디어학회논문지 Vol.19 No.8

In this paper, we propose a new real-time human detection under omni-directional cameras for visual surveillance purpose, based on CNN with unified detection and AGMM. Compared to CNN-based state-of-the-art object detection methods. YOLO model-based object detection method boasts of very fast object detection, but with less accuracy. The proposed method adapts the unified detecting CNN of YOLO model so as to be intensified by the additional foreground contextual information obtained from pre-stage AGMM. Increased computational time incurred by additional AGMM processing is compensated by speed-up gain obtained from utilizing 2-D input data consisting of grey-level image data and foreground context information instead of 3-D color input data. Through various experiments, it is shown that the proposed method performs better with respect to accuracy and more robust to environment changes than YOLO model-based human detection method, but with the similar processing speeds to that of YOLO model-based one. Thus, it can be successfully employed for embedded surveillance application.