Tran N.T.,Sejong University |
Tran N.T.,Ho Chi Minh City University of Transport |
Kim D.J.,Sejong University
Cement and Concrete Composites | Year: 2017
This study investigated the synergistic tensile response of blending 1% long and 0.5% short steel fibers in ultra-high-performance concrete (UHPC) at high strain rates of 16–37 s−1. Three ultra-high-performance hybrid-fiber-reinforced concretes (UHP-HFRCs) containing twisted, hooked, or smooth long (30 mm) fibers blended with short (13 mm) smooth fibers, as well as one sample (LS10MS05) blending long and medium (19 mm) smooth fibers, were examined. The blending of long and shorter steel fibers in UHPC generated high synergy in the tensile responses of the UHP-HFRCs, especially at high strain rates. Synergies were significant for strain capacity and peak toughness, but not for post-cracking strength and softening fracture energy. Among the long fibers, the hooked fibers generated the highest synergy at high strain rates, but smooth fibers produced the highest rate sensitivity in UHPC. Consequently, the LS10MS05 sample demonstrated the highest tensile resistance at high strain rates. © 2017 Elsevier Ltd
Do V.D.,Ho Chi Minh City University of Transport |
Dang X.K.,Ho Chi Minh City University of Transport |
Le A.T.,Baria Vungtau Province Vocational College
Proceedings - 2017 International Conference on Recent Advances in Signal Processing, Telecommunications and Computing, SigTelCom 2016 | Year: 2017
Vietnam is capable of building oil-rigs nowadays; however, the monitoring control system still relies on foreign technology and the lift system is based on semi-automatic balancing method. Therefore, studying automatic application and control algorithm for oild-rig balancing is in order of priority. In this paper, we survey fuzzy adaptive interactive controller (FAI) which applies a balancing rig model to stablize an oild-rig at a fixed location. The system is simulated by using Matlab under the effects of environmental factors such as operation cases and applied to experimental model. The proposed method results in a better performance compared to other linear control method such as Fuzzy-PID. © 2017 IEEE.
Nguyen T.T.,Ho Chi Minh City University of Transport |
Chan T.M.,Hong Kong Polytechnic University |
Mottram J.T.,University of Warwick
Composite Structures | Year: 2015
This paper presents an investigation into the development of a design procedure for Pultruded Fibre Reinforced Polymers (PFRP) beams failing by the elastic buckling mode of Lateral-Torsional Buckling (LTB). The design procedure is based on the European design approach for uniform members in bending of structural steel. In particular, the calibration method adopts the general case 'resistance' formula in Eurocode 3 (EN 1993-1-1:2005), and follows a standard design from testing procedure given in Eurocode 0 (EN 1990:2002) when calibrating the 'design model' to determine the partial factor γM for a member instability check. The test population for calibration has 114 LTB buckling resistances using four PFRP section sizes of I and channel shapes. The non-dimensional slenderness parameter is defined using the local flange buckling strength instead of the yield strength. An imperfection factor of 0.34 and partial factor of 1.3 are shown to be appropriate for calculation of the LTB moment of resistance. © 2015 Elsevier Ltd.
Ke T.N.,Ton Duc Thang University |
Khanh H.N.P.,Ho Chi Minh City University of Transport
Procedia Engineering | Year: 2016
Load capacity of pile foundation is larger than shallow foundation because the loads are transferred deeper into de stiffer layers of soil. Piles and the ground under the pile cap work simultaneously to lift and hold the above structure. The determination of cross section, length and arrangement piles accordance with load, geotechnical, construction equipment, conditions is a big challenge in the designing of pile foundation to achieve efficiency economy. Analysing the relationship between the stress of the ground and pile's load capacity to choose cross section, length and arrangement piles accordance with load, geotechnical, construction equipment, conditions will bring economy efficiency. In this paper a new method for determining the load capacity of pile based on the consideration stress in the ground under the tip of the pile and along the pile is presented. The loading capacity of a pile predicted using the proposed method is compared with the result of the static compression test carried out at the field. The analysis based on this comparison showed that this method efficiently help the designer in determining correctly the load capacity of piles after having results of the pile static compression tests. © 2016 The Authors. Published by Elsevier Ltd.
Bao V.N.Q.,Posts And Telecom Institute Of Technology |
Phuong B.P.L.,International University |
Thanh T.T.,Ho Chi Minh City University of Transport
2012 4th International Conference on Communications and Electronics, ICCE 2012 | Year: 2012
We first propose transmit antenna selection/selection combining (TAS/SC) based MIMO decode-and-forward (DF) relaying networks to simultaneously employ advantages offered by multi-hop relaying and TAS/SC. To investigate the system, we further propose to approximate the distribution of the end-to-end signal-to-noise ratio (SNR). The advantage of the proposed approximation resides mainly in the fact that it results in simple and mathematically tractable closed-form expression of the system performance metrics such as outage probability, ergodic capacity, symbol error rate and bit error rate thus offering clear insights on system behaviors. Monte-Carlo simulation results have been performed to cross-check the accuracy of the theoretical analysis showing that our proposed protocol outperforms the single-antenna-equipped multi-hop network in all range of operating SNRs. Under the constraint of spectral efficiency, the optimal number of hops is existed and a function of modulation schemes and path loss exponent. © 2012 IEEE.
Vu V.T.,Ho Chi Minh City University of Transport
Journal of Pressure Vessel Technology, Transactions of the ASME | Year: 2013
The paper presents the optimization of toroidal shell cross-sections under internal pressure. The wall thickness distribution along a circular centerline is derived in an analytical form. In membrane solution, this cross-section gives a constant Mises stress all over the shell. Therefore, it leads to material saving and contained volume increase in comparison with the traditional cross-section of circular constant thickness. The optimum shapes are designed for two states of shell, one is elasticity and the other is up to destruction. The maximum material saving can reach 70% in some configurations of toroid. Results of the proposed method are as good as or better than those found in literature. © 2013 by ASME.
Nguyen L.A.T.,Ho Chi Minh City University of Transport |
Nguyen H.K.,Ho Chi Minh City University of Transport
2015 10th Asian Control Conference: Emerging Control Techniques for a Sustainable World, ASCC 2015 | Year: 2015
The explosive growth of Internet commerce has made phishers who may attempt to create phishing sites aimed to steal personal information such as password, banking account and credit card account details, etc. Most of these phishing pages look similar to the real pages in terms of interface and uniform resource locator (URL) address. Many techniques have been proposed to identify phishing sites. However, the numbers of victims have been increasing due to inefficient protection technique. In this paper, we develop a fuzzy model for phishing identification efficiently. The model eliminates the subjective factors to improve efficiency such as if-then rule sets, the parameters of membership functions, etc. Moreover, the efficiency features for identifying phishing were used for the fuzzy model. The proposed technique is evaluated with the datasets of 11,660 phishing sites and 5,000 legitimate sites. The results show that the proposed technique can identify over 99% phishing sites. © 2015 IEEE.
Dang T.,Ho Chi Minh City University of Transport |
Bargstadt H.-J.,Bauhaus University Weimar
Journal of Construction Engineering and Management | Year: 2016
Four-dimensional (4D) schedules have proven successful in planning with their visualization capabilities allowing for coordination and time-space conflict detection. However, when considered in depth, internal aspects of 4D scheduling techniques have not made significant advances from traditional two-dimensional (2D) scheduling. What is missing from 4D scheduling? Why has the interaction between activities, their relationships, and three-dimensional (3D) components not been flexible and adaptive enough? In light of these questions, this paper analyzes the current state of 4D scheduling. The missing element in 4D scheduling is found to be 4D relationships (4DRs). A prototype of 4DRs has therefore been developed to improve 4D scheduling. Finally, guidance on the application of 4DRs in 4D scheduling is presented to help the users come to a thorough understanding of its advantages and disadvantages and potential applications. © 2015 American Society of Civil Engineers.
Tran T.N.,Ho Chi Minh City University of Transport |
Ton T.N.T.,Ho Chi Minh City University of Transport
Composite Structures | Year: 2016
One of the important topics in impact engineering was lateral crushing behaviour of thin-walled tube. In this study, crushing behaviours of rectangular and square tubes are investigated through lateral crushing testing and theoretical analysis. The average crushing force of the rectangular tube is smaller than that of the square tube. These two types of tubes have identical crushing mechanism, including two crushing stages. Plastic models are built based on the observed crushing behaviour. Theoretical solution for each stage is developed to predict the average crushing force of rectangular and square tubes. © 2016 Elsevier Ltd
Vu V.T.,Ho Chi Minh City University of Transport
International Journal of Geomechanics | Year: 2015
An approach to finding the optimal layout of prefabricated vertical drains (PVDs) in soft soil treatment, which has the minimum amount of PVDs and meets the requirements for the degree of consolidation, is proposed. Because explicit functions for settlement and consolidation in a multilayer ground for PVDs are not available, the current study uses the differential evolution method. The results show a stable relation between the optimal value with elapsed time, degree of consolidation, and embankment height. © 2014 American Society of Civil Engineers.