Improved Stability and Control Analysis Process for Detailed Design Stage of Light Aircraft

Le Viet Thang Nguyen,Nhu Van Nguyen,Jae-Woo Lee,Sangho Kim,Seung-Hyeog Nah 한국항공우주학회 2016 한국항공우주학회 학술발표회 논문집 Vol.2016 No.4

The improved stability and control (S&C) analysis process is developed and presented using wind tunnel test data to investigate the stability and control characteristics of a light aircraft complied with the KAS – VLA subpart B regulations and design requirements at detailed design stage. The enhanced stability and control analysis disciplines are developed for the corresponding KAS – VLA regulations and design requirements to use wind tunnel (W/T) test data, weight and propulsion data in order to improve the reliability of stability and control analysis results. In this study, the improved S&C process is applied for detailed design stage of light aircraft and complied with KAS – VLA to demonstrate the efficiency of the process.

Switchable Voltage Control of the Magnetic Anisotropy in Heterostructured Nanocomposites of CoFe/NiFe/PZT

Nguyen Thi Minh Hong,Nguyen Ba Doan,Nguyen Huy Tiep,Le Viet Cuong,Bui Nguyen Quoc Trinh,Pham Duc Thang,김동현 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.63 No.3

In this work, we study the magnetic properties of a CoFe/NiFe/PZT heterostructured nanocompositethat is affected by the strain in the PZT substrate when a voltage in the range from –250to 250 V is applied. An interesting electric-voltage-controlled magnetic anisotropy, with a relativeincrease in magnetization up to above 100%, is observed. This brings a new challenge to operate alow-power-consuming spin electronic device. We also utilize a theoretical model based on interfacecharge-mediated and strain-mediated magnetic-electric coupling to understand the change in themagnetic properties of the investigated material.

Guidance of Nerve Stimulator and Ultrasound for Transforaminal Epidural Steroid Injection in Lumbosacral Radicular Pain : A Single Institution Experience in Vietnam

Viet-Thang Le,Chi Hue Nguyen,Phuoc Trong Do,Anh Minh Nguyen,Khoi Hong Vo 대한신경외과학회 2024 Journal of Korean neurosurgical society Vol.67 No.2

Objective : This study aimed to evaluate the clinical feasibility of the combination of ultrasound and nerve stimulator guidance in transforaminal epidural steroid injections (TESIs) to manage lumbosacral chronic radicular pain. Methods : Using the combination of nerve stimulator and ultrasound guidance, TESIs were performed in 125 segments of 78 patients who presented with chronic lumbar radicular pain. Demographic characteristics and surgical outcomes were recorded on admission, pre-procedural and post-procedural for 1-week, 1-month, 3-month, and 6-month follow-ups. The result was measured using the Numeric rating scale (NRS) and Oswestry disability index (ODI). Results : Patients who received TESIs showed significant improvements on two evaluation tools (NRS, ODI), compared to that before procedure (p<0.001). No significant complications were observed for 6 months’ follow-up. Conclusion : The result suggests that a combination of ultrasound and nerve stimulator guidance in transforaminal epidural injections is safe, reliable and effective for short-term management of lumbar disc herniation. It is a promising technique and has shown good results in providing intermediate pain relief.

Childhood Emotional, Physical, and Sexual Abuse and Associations With Mental Health and Health-Risk Behaviors Among University Students in the Association of Southeast Asian Nations (ASEAN)

Thang, Nguyen Huu,Anh, Le Viet,Peltzer, Karl,Pengpid, Supa,Low, Wah Yun,Win, Hla Hla Korean Association of Child Studies 2017 Child studies in Asia-Pacific context Vol.2 No.1

The aim of this study was to retrospectively estimate the prevalence of childhood emotional abuse (CEA), childhood physical abuse (CPA), and childhood contact sexual abuse (CCSA) in relation to adult poor mental health, addictive behavior, and other health-risk behaviors among university students in five ASEAN countries (Indonesia, Malaysia, Myanmar, Thailand, and Vietnam). In a cross-sectional survey, 3,240 undergraduate university students were randomly selected (M age = 20.5 years, SD = 1.6 years) to respond to a questionnaire including the Abuse section of the World Health Organization (WHO) Version 1 "Adverse Childhood Experiences International Questionnaire" (ACE-IQ) and other measures. The students reported 17.9% CEA, 28.2% CPA, and 22.4% CCSA, with the highest prevalence of CEA in Myanmar (30.9%) and CPA and CCSA in Vietnam (55.8% and 41.6%, respectively). In logistic regression models, adjusting for sociodemographic and social variables, the separate and cumulative effects of three types of child abuse (emotional, physical, and sexual) were found to increase the risks for poor adult mental health, addictive, and other health-risk behaviors.

“UAV Sensor Selection Based on Aerial Mapping Mission Specific Requirements”

Aye Aye Maw,Nguyen Le Viet Thang,Maxim Tyan,Jae-Woo Lee 한국항공우주학회 2016 한국항공우주학회 학술발표회 논문집 Vol.2016 No.4

System flexibility and efficient flight automation algorithms make UAV a popular platform for various aerial mapping applications. Small sized UAVs are the prior option for the most part of mapping applications due to low price and ease of operation. The use of UAVs for professional geographic information system or precision agriculture sets very strict requirements to image quality. The selection of appropriate image recording equipment becomes essential for providing the sharp images with high resolution. This paper describes the methodology for calculating the required flight conditions and mission efficiency of an existing electric UAV to satisfy the mission requirements. Scoring method is applied to select the required setup of a visual sensor.

Novel proximal fish freshness monitoring using batteryless smart sensor tag

Chung, Wan-Young,Le, Giang Truong,Tran, Thang Viet,Nguyen, Nam Hoang Elsevier 2017 Sensors and actuators. B Chemical Vol.248 No.-

<P><B>Abstract</B></P> <P>Fish is the most perishable of fresh foods, but it is held in high regard for its flavor, taste and nutrition for the human body. Until now, most studies on monitoring the freshness of fish have used semiconducting metal oxide sensors that consume much power in sensing operation. To supply the operational sensing power and the power for wireless communication, any wireless sensor module needs a battery attached, and this entails extra effort for a regular battery change. Therefore, we developed a novel fish monitoring system in which no battery is needed for the sensing module. This study proposes a novel proximal fish freshness monitoring system. The novel smart sensing tag module has been developed as a self-powered device by using an additional energy harvesting circuit that operates at a frequency of 13.56MHz. The harvester can collect sufficient radio frequency (RF) energy from the reader by using RF energy coupling within a maximum distance of 30cm; then, the received power is stored in a single energy chip for supplying to the sensing circuit. The fish freshness is monitored by sensor modules for temperature and either hydrogen sulfide (H<SUB>2</SUB>S) or ammonia (NH<SUB>3</SUB>) gas concentration measurement in the fish packaging. The sensing module is designed using ultra-low-power sensors that consume less than ∼10mW, enabling us to extend the distance between the RF reader and the smart sensor tag for effective RF energy coupling and sensing data transmission. The results of freshness monitoring of a seafish package are classified into four grades to indicate the food quality: good, normal, caution, and bad. The proposed sensor tag can be used to predict the quality of packaged fish by accurate monitoring of temperature and the concentration of H<SUB>2</SUB>S or NH<SUB>3</SUB> in range of −40 to 105°C, 0–200ppm, and 0–100ppm, respectively.</P> <P><B>Highlights</B></P> <P> <UL> <LI> To supply the operational sensing power and the power for wireless communication, any wireless sensor module needs a battery attached, and this entails extra effort for a regular battery change. </LI> <LI> We developed a novel fish monitoring system in which no battery is needed for the sensing module. This study proposes a novel proximal fish freshness monitoring system. </LI> <LI> The novel smart sensing tag module has been developed as a self-powered device by using an additional energy harvesting circuit that operates at a frequency of 13.56MHz. The fish freshness is monitored by sensor modules for temperature and either hydrogen sulfide (H<SUB>2</SUB>S) or ammonia (NH<SUB>3</SUB>) gas concentration measurement in the fish packaging. The sensing module is designed using ultra-low-power sensors that consume less than ∼10mW, enabling us to extend the distance between the RF reader and the smart sensor tag for effective RF energy coupling and sensing data transmission. </LI> <LI> The results of freshness monitoring of a seafish package are classified into four grades to indicate the food quality: good, normal, caution, and bad. The proposed sensor tag can be used to predict the quality of packaged fish by accurate monitoring of temperature and the concentration of H<SUB>2</SUB>S or NH<SUB>3</SUB> in range of −40 to 105°C, 0–200ppm, and 0–100ppm, respectively. </LI> </UL> </P>

A Data-centric Analysis to Evaluate Suitable Machine-Learning-based Network-Attack Classification Schemes

Huong, Truong Thu,Bac, Ta Phuong,Thang, Bui Doan,Long, Dao Minh,Quang, Le Anh,Dan, Nguyen Minh,Hoang, Nguyen Viet International Journal of Computer ScienceNetwork S 2021 International journal of computer science and netw Vol.21 No.6

Since machine learning was invented, there have been many different machine learning-based algorithms, from shallow learning to deep learning models, that provide solutions to the classification tasks. But then it poses a problem in choosing a suitable classification algorithm that can improve the classification/detection efficiency for a certain network context. With that comes whether an algorithm provides good performance, why it works in some problems and not in others. In this paper, we present a data-centric analysis to provide a way for selecting a suitable classification algorithm. This data-centric approach is a new viewpoint in exploring relationships between classification performance and facts and figures of data sets.