Peng K.,CISDI Group Co. |
Peng K.,Shanghai JiaoTong University |
Yang Y.,Shanghai JiaoTong University
Asian Journal of Control | Year: 2011
In this paper, we consider a collective tracking problem of a multi-agent system which has a varying-velocity leader and evolves on balanced information topologies. First, we propose a coordination-variable-based control strategy for every agent to track the leader whose state may not be measured. Moreover, from a collective behavior perspective, a new decomposition method is utilized to decompose the resulting closed-loop system into two subsystems, and a novel measure also is introduced to characterize collective tracking performance of the system. Finally, we prove that the proposed control strategy can not only estimate the tracking errors but also increase the introduced measure to improve collective tracking performance even under the case of balanced information topologies. © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society.
Xiao X.,CISDI Group Co. |
Zhang Q.,Hong Kong University of Science and Technology |
Shi Y.,Tsinghua University |
Gao Y.,Tsinghua University
IEEE Transactions on Parallel and Distributed Systems | Year: 2012
In this paper, we propose a service differentiation incentive for P2P streaming system, according to peers' instant contributions. Also, a repeated game model is designed to analyze how much the peers should contribute in each round under this incentive. Simulations show that satisfying streaming quality is achieved in the Nash Equilibrium state. © 2006 IEEE.
Zhang G.,Renmin University of China |
Shen Q.,CISDI Group Co.
Advanced Materials Research | Year: 2012
A novel three-stage catalytic ozonation-BAC process is proposed to treat highly polluted source water. A pilot study of 120 m 3/d was performed in south China and lasted 9 months. The results showed that catalysts improved the THMsFP reduction efficiency by around 18% for BAC step and reduced the effluent bromate by 20%-77%; reduced NH 4-N to below 1 mg/L; The effluent COD met the national standard under all circumstances. © (2012) Trans Tech Publications.
Chen J.,CISDI Group Co. |
Liu X.,CISDI Group Co.
Separation and Purification Technology | Year: 2010
Simulations on the separation efficiency and the pressure drop of a modified cyclone separator with a novel exhaust under different insert depths (250 mm, 350 mm, 450 mm, and 550 mm), sloping orientations (0°, 90°, 180°, and 270°), contracting angles (15°, 30°, and 45°) and sloping angles (5°, 10°, and 15°) were performed by computational fluid dynamics technique in this study. Results indicate that despite the pressure drop increases to some extent, the separation efficiency of such separators fundamentally exceeds that of the traditional linear-pipe-shaped ones due to the configuration of the novel exhaust can be made to harmonize with the flow field within the separator. Both the separation efficiency and the pressure drop change with the sloping orientation, and they have the same changing rule, the maximum at 90° and the minimum at 270°. The separation efficiency increases firstly and then decreases with increasing insert depth of the novel exhaust, and the maximum appears when the insert depth is 450 mm. The separation efficiency of the modified separator is about 4.6-7.9% higher than that of the traditional one under different sloping angles and contracting angles. Simulation results agree relatively well with the previous experimental results. Besides, based on an overall consideration of separation efficiency and pressure drop, we think that it is the most economic condition when the contracting angle is 30°. However, the contracting angle of 45° is still more suitable when the key problem is the separation efficiency despite its largest resistance loss. © 2010 Elsevier B.V. All rights reserved.
Tang Y.,CISDI Group Co.
Manufacturing and Engineering Technology - Proceedings of the 2014 International Conference on Manufacturing and Engineering Technology, ICMET 2014 | Year: 2015
In order to improve fatigue life of high-speed wheel steel, LF-VD secondary-refining process is carried on with Al-deoxidation and slag of high basicity, high Al2O3 content and low oxidizing property. It is found that inclusion transformation process would be influenced obviously by slag compostion, which is the key for the enhancement of fatigue performance for wheel steel. © 2015 Taylor and Francis Group, London.
He Z.,Northeastern University China |
Tian G.-W.,CISDI Group Co.
Engineering Structures | Year: 2011
With an additional target reliability index of 1.098, the Rackwitz-Fiessler method was used to evaluate the coefficients associated with the design development length of a GFRP rod in concrete in the case of pull-out bond failures. As a result of the evaluation, the coefficients are proposed to be 0.0816 and 0.0933 for ordinary and aggressive exposures, respectively. The coefficient of variation of GFRP strength could exert the most significant influence on averaged coefficients. The effects of diameter and GFRP average strength greater than 750 MPa are found to be negligible. A linear relationship between the averaged coefficient and additional target reliability could be employed for developing a performance-based bond design methodology. With the combination of flexural analysis, the proposed relationship between the averaged coefficient and the so-called strength utilization factor could be applied to for the determination of a customized design development length of a GFRP rod in concrete. © 2011.
Yu T.,CISDI Group Co.
Advanced Materials Research | Year: 2013
In order to improve fatigue life of wheel steel, secondary-refining process is done with Al-deoxidation and slag of high basicity, high Al2O3 content and low oxidizing property. [Mg], [Ca] content in molten steel would be influenced by slag composition. It is found that high basicity, high Al2O3 content and low oxidizing property is positive factor for proper [Mg], [Ca] content in molten steel which is the key of inclusion transformation from Al2O3 to CaO-MgO-Al2O3 complex inclusion, contributing to the enhancement of fatigue performance for wheel steel. © (2013) Trans Tech Publications, Switzerland.
Tang Y.,CISDI Group Co.
Procedia Earth and Planetary Science | Year: 2011
Inclusion control in LF-VD process for ultra-low oxygen alloyed structural steel is investigated. It is found that after Al-deoxidation during tapping process, with slag of high basicity, high Al 2O 3 content and low oxidizing property, Al 2O 3 inclusions, which are the product of Al-deoxidation could transform to MgO-Al 2O 3 spinel, and later on to CaOMgO-Al 2O 3 inclusions of lower melting point, which are inclined to be eliminated by floatation, thus total oxygen content would be lowered. On the other hand, residual inclusions in steel are mostly ultra-fine in size, and could be deformed slightly in hot-working process of steel, enhancing fatigue life of steel. © 2011 Published by Elsevier Ltd.
Tian G.-W.,CISDI Group Co.
Materials and Structures/Materiaux et Constructions | Year: 2011
Most of proposed models available so far associated with the evaluation of design embedded length of fiber reinforced polymer (FRP) rods in concrete are not reliability-based. This paper made an attempt, from the probabilistic standpoint, to determine the design embedded length of a glass fiber reinforced polymer (GFRP) rod in the case of splitting bond failure from concrete. The mathematical model put forward by Orangun et al. for evaluating the average bond strength of reinforcing bars in concrete for splitting failure has been adopted to develop the nonlinear limit state function corresponding to GFRP's splitting bond failure in which five independent random variables, i.e. concrete strength, GFRP tensile strength, embedded length, GFRP diameter and computational uncertainty factor, are included. As the result of the probabilistic calibration procedures using the Rackwitz-Fiessler method, a non-dimensional factor K associated closely with the design embedded length of a GFRP rod in concrete is proposed to be 0.0306 with the suggested additional target reliability index of 1.10. The effects of some factors on GFRP's design embedded length have been identified through the following parametric study. Although the calibration process is case-dependent to some extent, the proposed formula is thought to be acceptable for general bond design purposes of GFRP-reinforced concrete components. © RILEM 2010.
Zhou M.,CISDI Group Co.
Advanced Materials Research | Year: 2013
The fluid flow of liquid metal in ladles of CAS-OB refining process is a complicated turbulent transmission process. It behaves much more complicated than in traditional ladle because of immersion snorkel. This paper describes properties of liquid metal based on full buoyancy model. The author analyzes the characteristics of flow field in single and double-nozzles bottom blowing condition through numerical simulation method. Double-nozzles bottom blowing could improve blending effect in the region where is weak mixing. This paper also draws an empirical formula which tells how gas blowing and immersion depth influence mixing time in CAS-OB ladle through dimensionless analysis: © (2013) Trans Tech Publications, Switzerland.