LOWER EXTREMITY INJURY OF VIETNAMESE PEDESTRIAN IN CRASH BY A SEDAN USING NUMERICAL SIMULATION

Phu Thuong Luu Nguyen,Hung Anh Ly,Thien Phu Nguyen 한국자동차공학회 2023 International journal of automotive technology Vol.24 No.1

Pedestrians are among the most vulnerable road users, who often suffer serious injuries in road collisions. Therefore, evaluating the injury of a pedestrian is absolutely necessary. This paper aims to evaluate the lower extremity injuries for Vietnamese people by numerical simulation using a Human Body Model (HBM) – Total Human Model for Safety (THUMS). Considering that the HBM has the anthropometrical and biomechanical properties of the North American and European bodies, it is required to scale it down to represent Vietnamese anthropometry. Furthermore, it is necessary to develop a scaling algorithm to scale the published lower extremity injury criteria to properly assess the injury risk of a Vietnamese. After a Vietnamese-sized HBM is obtained from the scaling procedure, its posture is adjusted to represent a walking pedestrian. A sedan is employed for simulating the pedestrian collision with the impact velocity ranging from 20 to 50 km/h. The car models are simplified to reduce computational time. The findings illustrate that the bending moment and resultant force of femur and tibia increase with respect to the impact velocity. The knee ligaments have been injured at high risk.

Securing AODV Routing Protocol in Mobile Ad-Hoc Networks

Phu, P.H.,Yi, M.,Kim, M.-K. Springer 2009 Lecture Notes in Computer Science Vol.- No.4388

Vibration control of a vehicle’s seat suspension featuring a magnetorheological damper based on a new adaptive fuzzy sliding-mode controller

Phu, Do Xuan,Choi, Seung-Bok,Lee, Yang-Sub,Han, Moon-Sihk Professional Engineering Publishing Ltd 2016 Proceedings of the Institution of Mechanical Engin Vol. No.

<P>This work presents a new design for adaptive fuzzy sliding-mode control based on two methodologies, namely H control and sliding-mode control, and its control effectiveness. This is achieved by implementing a control scheme for vibration control of a vehicle with a seat suspension on which a magnetorheological damper is installed. The sliding surface of sliding-mode control is analysed by separation into two matrices: a Hurwitz-constants matrix and a constant matrix. These matrices are the basis for establishing the proposed control scheme combined with the H technique. The control scheme consisting of the combination of H control and sliding-mode control is reinforced by a new robustness function featuring an exponential function. In this work, a fuzzy logic model, which is well known to be an excellent model for uncertain dynamic systems, is integrated with the proposed control algorithm. The fuzzy logic model adopted in this work is an interval type-2 fuzzy model featuring fast computation of the output. The effectiveness of the proposed control scheme is evaluated through both computer simulations and experimental realization on a vehicle with a seat suspension which is equipped with a magnetorheological damper. In addition, in this work, two existing adaptive controllers are modified and implemented for comparative work with the proposed control scheme. It is shown that the proposed control scheme exhibits a much better vibration control performance than the two existing adaptive controllers do.</P>

Targeting the Phosphatidylinositol-3-kinase Pathway in Gastric Cancer: Can Omics Improve Outcomes?

Phu Tran,Cham Nguyen,Samuel J. Klempner 대한배뇨장애요실금학회 2016 International Neurourology Journal Vol.20 No.S1

Phosphatidylinositol-3-kinase (PI3K) pathway signaling is an established oncogenic signal transduction pathway implicated in multiple malignancies. Therapeutic targeting of PI3K pathway components has improved outcomes in chronic lymphocytic leukemia, kidney cancer, breast cancer, and neuroendocrine tumors. Gastric cancers harbor some of the highest rates of oncogenic alterations in PI3K but attempts to translate this genomic observation have met with limited clinical success and novel approaches are needed. In the following review we discuss PI3K signaling, previous preclinical and clinical investigations in gastric cancer, and discuss future strategies aimed at overcoming resistance and improving efficacy. Identification and refinement of molecular tumor subtypes, development of predictive biomarkers along, and rational drug combination strategies are key to capitalizing on the therapeutic potential of PI3K pathway directed therapies in gastric cancers.

An Efficient Chloride Ingress Model for Long-Term Lifetime Assessment of Reinforced Concrete Structures Under Realistic Climate and Exposure Conditions

Phu Tho Nguyen,Emilio Bastidas-Arteaga,Ouali Amiri,Charbel-Pierre El Soueidy 한국콘크리트학회 2017 International Journal of Concrete Structures and M Vol.11 No.2

Chloride penetration is among the main causes of corrosion initiation in reinforced concrete (RC) structures producing premature degradations.Weather and exposure conditions directly affect chloride ingress mechanisms and therefore the operational service life and safety of RC structures. Consequently, comprehensive chloride ingress models are useful tools to estimate corrosion initiation risks and minimize maintenance costs for RC structures placed under chloride-contaminated environments. This paper first presents a coupled thermo-hydro-chemical model for predicting chloride penetration into concrete that accounts for realistic weather conditions. This complete numerical model takes into account multiple factors affecting chloride ingress such as diffusion, convection, chloride binding, ionic interaction, and concrete aging. Since the complete model could be computationally expensive for long-term assessment, this study also proposes model simplifications in order to reduce the computational cost. Long-term chloride assessments of complete and reduced models are compared for three locations in France (Brest, Strasbourg and Nice) characterized by different weather and exposure conditions (tidal zone, de-icing salts and salt spray). The comparative study indicates that the reduced model is computationally efficient and accurate for long-term chloride ingress modeling in comparison to the complete one. Given that long-term assessment requires larger climate databases, this research also studies how climate models may affect chloride ingress assessment. The results indicate that the selection of climate models as well as the considered training periods introduce significant errors for mid- and long- term chloride ingress assessment.

Detection and Quantification of Major Royal Jelly Protein 1 in Honeybees by ELISA using a Monoclonal Antibody

Phu Van Nguyen,Ji-Na No,Bo-Ram Lee,Mi-Sun Yoo,Byoung-Su Yoon 한국양봉학회 2011 韓國養蜂學會誌 Vol.26 No.1

Enzymatic Synthesis of Pure Maltohexaose from α-Cyclodextrin

Phu Cuong Nguyen,Ji-Yun Kwak,Min-Jee Yoo,Jong-Tae Park,Kwan-Hwa Park 한국당과학회 2016 한국당과학회 학술대회 Vol.2016 No.01

Maltohexaose (G6) is a maltodextrin consisted of six-glucose in α-1,6-glycosidic linkages and essential research tool in food, cosmetic and pharmaceutical. In previous study, we have proven that the possibility of large-scale continuous production of pure maltodextrins from cyclodextrins (CDs) using Pyrococcus furiosus thermostable amylase with immobilization in a packed-bed reactor (PBR). In this study, we used this PBR for G6 production from α-CD. After enzyme reaction, 1-decanol was added to G6 mixture as precipitating agent with a 1:1 ratio of 1-decanol to α-CD. In which, the unreacted α-CD was precipitated, then it was separated by centrifugation. Finally, the G6-product was obtained in homogeneous form and high-purity (95 %). Through this study, we successfully demonstrated the enzymatic synthesis method to produce pure G6 from α-CD.

Enzymatic synthesis of pure maltodextrins and their novel derivatives

Phu Cuong Nguyen,My Tuyen Thi Nguyen,Chang-Kyu Lee,Wang-Hee Lee,Il-Nam Oh,Jae-Han Kim,Soon-Taek Hong,Jong-Tae Park 한국당과학회 2022 한국당과학회 학술대회 Vol.2022 No.07

Maltodextrin in specific length is of great interest because of its wide industrial applications. Previously, we have proven that Pyrococcus furiosus thermostable amylase (PFTA) produces high purity maltoheptaose (G7) from β-cyclodextrin (CD) at early reaction time. However, the production of pure G7 is a cost and time-consuming process. Therefore, this work has designed an optimal continuous process for pure G7 production from β-CD using PFTA with immobilization in a packed-bed reactor (PBR). The optimal conditions determined using the response surface method for the maximized G7-purity of 96.3% were predicted at 4.7 ml/min of flow rate, 1.1% substrate, and 48.7 °C. As a result, the immobilized PFTA in PBR retained 85% of the initial activity after six cycles of 24 h intervals, and the product purity was unchanged. Also, maltohexaose (G6) and maltooctaose (G8) at high purity (92-97%) were produced by continuously supplying CDs to the PFTA-PBR under the same optimized condition of G7. In addition, a new method based on preparative reversed-phase liquid chromatography was developed to purify maltodextrins in specific lengths (DP 3-26) with high purity from the reaction mixture of G6-G8 substrates with Thermotoga maritima maltosyltransferase. On the other hand, novel G7-based sugar esters were also synthesized and investigated for emulsifying properties. As a result, G7-fatty acids (C10–C16) esters were produced with a high conversion yield (90-95%) under the optimal conditions (10% of DMSO, 0.2 of G7/ fatty acids molar ratio, 33.5 U of immobilized Candida antarctica lipase B) for 24 h of incubation at 60 °C. Notable, G7-palmitate (PA) exhibited emulsifying properties better than commercial sucrose-PA ester, especially in acidic conditions. It is feasible that the number of the hydroxyl groups and the size of G7 moiety provide that distinctive property of G7-PA. Therefore, applications of G7-PA in foods, cosmetics, and drug delivery under extreme pH conditions are promising.

Advanced analysis for planar steel frames with semi-rigid connections using plastic-zone methodAdvanced analysis for planar steel frames with semi-rigid connections using plastic-zone method

Phu-Cuong Nguyen,김승억 국제구조공학회 2016 Steel and Composite Structures, An International J Vol.21 No.5

This paper presents a displacement-based finite element procedure for second-order distributed plasticity analysis of planar steel frames with semi-rigid beam-to-column connections under static loadings. A partially strain-hardening elastic-plastic beam-column element, which directly takes into account geometric nonlinearity, gradual yielding of material, and flexibility of semi-rigid connections, is proposed. The second-order effects and distributed plasticity are considered by dividing the member into several sub-elements and meshing the cross-section into several fibers. A new nonlinear solution procedure based on the combination of the Newton-Raphson equilibrium iterative algorithm and the constant work method for adjusting the incremental load factor is proposed for solving nonlinear equilibrium equations. The nonlinear inelastic behavior predicted by the proposed program compares well with previous studies. Coupling effects of three primary sources of nonlinearity, geometric imperfections, and residual stress are investigated and discussed in this paper.

Design of a novel adaptive fuzzy sliding mode controller and application for vibration control of magnetorheological mount

Phu, Do Xuan,Quoc, Nguyen Vien,Park, Joon-Hee,Choi, Seung-Bok Professional Engineering Publishing Ltd 2014 Proceedings of the Institution of Mechanical Engin Vol. No.

<P>This paper presents vibration control of a mixed-mode magnetorheological fluid-based mount system using a new robust fuzzy sliding mode controller. A novel model of controller is built based on adaptive hybrid control of interval type 2 fuzzy controller incorporating with a new modified sliding mode control. The interval type 2 fuzzy is optimized for computational cost by using enhanced iterative algorithm with stop condition, and a new modified switching surface of sliding mode control is designed for preventing the chattering of the system. The controller is then experimentally implemented under uncertain conditions in order to evaluate robust vibration control performance. In addition, in order to demonstrate the effectiveness of the proposed controller, two fuzzy sliding mode control algorithms proposed by Huang and Chan are adopted and modified. The principal control parameters of three controllers are updated online by adaptation laws to meet requirements of magnetorheological mount system which has two operation modes: flow mode and shear mode. It is shown from experimental realization of three controllers that the proposed control strategy performs the best under uncertain conditions compared with two other modified controllers. This merit is verified by presenting vibration control performances in both time and frequency domains.</P>