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101.
102.
The first measurement of a turnover rate with respect to surface intermediate concentration in a high pressure heterogeneous catalytic reaction is reported. By using infrared-visible sum frequency generation to study the hydrogenation of ethylene on Pt(111), it was found that the surface concentration of -bonded ethylene, the key reaction intermediate, represented approximately 4% of a monolayer. Thus the absolute turnover rate per surface adsorbed ethylene molecule is 25 times faster than the rate measured per platinum atom. To explain these results, we propose a model of weakly adsorbed ethylene intermediates reacting on atop sites. 相似文献
103.
Wei-Wei Che Guang-Hong Yang 《International Journal of Control, Automation and Systems》2011,9(5):993-997
The non-fragile dynamic output feedback H
∞ controller design problem is investigated. The controller to be designed is assumed to be with additive gain variations.
A two-step procedure is proposed to develop sufficient conditions for the non-fragile H
∞ controller design by employing the structured vertex separator. A comparison between the proposed and the existing controller
design methods is provided, and a numerical example is carried out to support the theoretical findings. 相似文献
104.
105.
Research on the group decision-making about emergency event based on network technology 总被引:1,自引:1,他引:0
Kefan Xie Gang Chen Qian Wu Yang Liu Pan Wang 《Information Technology and Management》2011,12(2):137-147
In order to improve decision-making efficiency about emergency event, this paper proposes a novel concept, i.e., Agile-Delphi
Method, which is an integration of agile decision and Delphi Method implicating that the decision-makers instantly deliver,
respond, treat, and utilize information via Delphi process while conducting group decision-making about emergency event. The
paper details the mechanism of group decision-making about emergency event based on network technology and Agile-Delphi Method.
Finally, the paper conducts an empiric analysis taking the “111 event”, i.e., the liquid ammonia spill event happened on November
1, 2006 in a phosphorus chemical company in China, as an example. 相似文献
106.
The twisted cube is an important variant of the most popular hypercube network for parallel processing. In this paper, we consider the problem of embedding multi-dimensional meshes into twisted cubes in a systematic way. We present a recursive method for embedding a family of disjoint multi-dimensional meshes into a twisted cube with dilation 1 and expansion 1. We also prove that a single multi-dimensional mesh can be embedded into a twisted cube with dilation 2 and expansion 1. Our work extends some previously known results. 相似文献
107.
Xin Zhang Zhangye Wang Ran Wang Zhonglei Yang Wei Chen Qunsheng Peng 《The Visual computer》2010,26(6-8):923-932
In recent years, several techniques have been proposed to simulate the gaze effect of the Human Visual System (HVS). It is believed that this effect is due to the foveation filtering. Current techniques to simulate the foveation filtering in computer graphics are either slow or suffer from artifacts and limitations. In this paper, we present a new approach of foveation filtering based on the Mipmap Pyramid of the current view by considering the relationship between the Gaussian kernel and Mipmap level. Due to the nonlinear Mipmap interpolation under the Bilateral Filtering scheme, we are able to simulate the foveation filtering more naturally and efficiently than in previous work. Moreover, a detail enhancement method based on the Cornsweet illusion is proposed to augment the gazing effect. We demonstrate our new approach with a variety of examples and provide comparisons with recent approaches. 相似文献
108.
109.
110.
This paper presents an improved ant colony optimization algorithm (IACO) for solving mobile agent routing problem. The ants cooperate using an indirect form of communication mediated by pheromone trails of scent and find the best solution to their tasks guided by both information (exploitation) which has been acquired and search (exploration) of the new route. Therefore the premature convergence probability of the system is lower. The IACO can solve successfully the mobile agent routing problem, and this method has some excellent properties of robustness, self-adaptation, parallelism, and positive feedback process owing to introducing the genetic operator into this algorithm and modifying the global updating rules. The experimental results have demonstrated that IACO has much higher convergence speed than that of genetic algorithm (GA), simulated annealing (SA), and basic ant colony algorithm, and can jump over the region of the local minimum, and escape from the trap of a local minimum successfully and achieve the best solutions. Therefore the quality of the solution is improved, and the whole system robustness is enhanced. The algorithm has been successfully integrated into our simulated humanoid robot system which won the fourth place of RoboCup2008 World Competition. The results of the proposed algorithm are found to be satisfactory. 相似文献