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91.
We present an in-depth treatment of model checking algorithms for a class of infinite-state continuous-time Markov chains known as quasi-birth death processes. The model class is described in detail, as well as the logic CSL to express properties of interest. Using a new property-independency concept, we provide model checking algorithms for all the CSL operators. Special emphasis is given to the time-bounded until operator for which we present a new and efficient computational procedure named uniformization with representatives. By the use of an application-driven dynamic stopping criterion, the algorithm stops whenever the property to be checked can be certified (or falsified). A comprehensive case study of a connection management system shows the versatility of our new algorithms. 相似文献
92.
目前基于马尔科夫链的扫雷作战效果评估模型从单链到多链,理论模型与算法设计已经架构完毕,但该模型的可信度还有待验证。文中利用误差分布拟合检验的方法,对模型可信度进行验证,计算表明,该模型可信度较好。 相似文献
93.
An image multi-scale edge detection method based on anti-symmetrical bi-orthogonal wavelet is given in theory. Convolution operation property and function as a differential operator are analyzed,which anti-symmetrical bi-orthogonal wavelet transform have. An algorithm for wavelet reconstruction in which multi-scale edge can be detected is put forward. Based on it, a detection method for small target in infrared image with sea or sky background based on the anti-symmetrical bi-orthogonal wavelet and morphology is proposed. The small target detection is considered as a process in which structural background is removed, correlative background is suppressed, and noise is restrained. In this approach, the multi-scale edge is extracted by means of the anti-symmetrical bi-orthogonal wavelet decomposition. Then, module maximum chains formed by complicated background of clouds, sea wave and sea-sky-line are removed, and the image background becomes smoother. Finally, the morphology based edge detection method is used to get small target and restrain undulate background and noise. Experiment results show that the approach can suppress clutter background and detect the small target effectively. 相似文献
94.
Margot J. Hutchins Stefanie L. RobinsonAuthor VitaeDavid DornfeldAuthor Vitae 《Journal of Manufacturing Systems》2013
Developing sustainable products and processes is growing in importance due to increasing regulation, consumer interest, access to information, and competitive forces. In order to adequately evaluate the sustainability of products and processes, there is a need to consider the impacts from all three pillars of sustainability – society, environment, and economics. There are substantial challenges to identifying and understanding the social impacts associated with manufacturing activities. This paper provides a framework for characterizing the social impacts of manufacturing throughout the life cycle of a product or process. Social impacts occur on various scales in manufacturing, from the level of a unit process to the level of the enterprise. Additionally, manufacturing activities impact consumers, communities, and larger political/spatial realms. This paper identifies key characteristics of social impacts associated with manufacturing that should be considered to more effectively address the social dimension of sustainability for products and processes. Examples involving a typical manufacturing process – welding – are presented to illustrate the utility of the framework. 相似文献
95.
Alexandru Agapie Mircea Agapie Gheorghita Zbaganu 《International journal of systems science》2013,44(3):502-512
From a global viewpoint, evolutionary algorithms (EAs) working on continuous search-spaces can be regarded as homogeneous Markov chains (MCs) with discrete time and continuous state. We analyse from this viewpoint the (1?+?1)EA on the inclined plane fitness landscape, and derive a closed-form expression for the probability of occupancy of an arbitrary target zone, at an arbitrary iteration of the EA. For the hitting-time of an arbitrary target zone, we provide lower and upper bounds, as well as an asymptotic limit. Discretization leads to an MC with discrete time, whose simple structure is exploited to carry out efficient numerical investigations of the theoretical results obtained. The numerical results thoroughly confirm the theoretical ones, and also suggest various conjectures which go beyond the theory. 相似文献
96.
Meliksah Ertugrul Okyay Kaynak Feza Kerestecioglu 《International journal of systems science》2013,44(9):1099-1106
In this paper, a novel scheme is proposed to adapt the gains of a sliding mode controller (SMC) so that the problems faced in its practical implementations as a motion controller are overcome. A Lyapunov function is selected for the design of the SMC and an MIT rule is used for gain adaptation. The criterion that is minimized for gain adaptation is selected as the sum of the squares of the control signal and the sliding surface function. This novel approach is tested on a scara-type robot manipulator. The experimental results presented prove its efficacy. 相似文献
97.
Jakob Ruess Andreas Milias-Argeitis John Lygeros 《Journal of the Royal Society Interface》2013,10(88)
Exploiting the information provided by the molecular noise of a biological process has proved to be valuable in extracting knowledge about the underlying kinetic parameters and sources of variability from single-cell measurements. However, quantifying this additional information a priori, to decide whether a single-cell experiment might be beneficial, is currently only possible in systems where either the chemical master equation is computationally tractable or a Gaussian approximation is appropriate. Here, we provide formulae for computing the information provided by measured means and variances from the first four moments and the parameter derivatives of the first two moments of the underlying process. For stochastic kinetic models for which these moments can be either computed exactly or approximated efficiently, the derived formulae can be used to approximate the information provided by single-cell distribution experiments. Based on this result, we propose an optimal experimental design framework which we employ to compare the utility of dual-reporter and perturbation experiments for quantifying the different noise sources in a simple model of gene expression. Subsequently, we compare the information content of a set of experiments which have been performed in an engineered light-switch gene expression system in yeast and show that well-chosen gene induction patterns may allow one to identify features of the system which remain hidden in unplanned experiments. 相似文献
98.
《Journal of Adhesion Science and Technology》2013,27(6):495-502
Very long grafted chains on a solid surface may turn out to be interesting adhesion promoters. Systems of this sort are now chemically accessible and must be characterized through their wetting properties. Here we discuss the climbing of a liquid along a vertical plane covered with long grafted polymer chains (N monomers per chain). Assuming that the liquid is a good solvent for the polymer, we calculate the thickness L of the swollen polymer brush as a function of the graft density os and reduced altitude h= k2-ah (where k-1 is the capillary length and a is the monomer size). (1) At small altitudes (h<hc1=o4/3 s), L(h) results mainly from a balance between excluded-volume and entropic effects, shift is not linear in h and is large. This remarkable effect reflects the existence of a parabolic concentration profile in the unperturbed brush, first derived by Milner, Witten and Cates (a simpler, Flory, model with a step function profile would give a much smaller effect). (2) At altitudes h > hc1, the solvent condensation energy becomes the leading term and At even higher altitudes a third 'mushroom' regime may show up if the polymer does not wet the solid. Our results are consistent with some preliminary observations of Deruelle and Léger on very long brushes of p-dimethylsiloxane 4000). Their brushes show colour variations with altitude 1 cm). The corresponding values of are rather large; thus the colour effect may give a rather direct experimental proof of the parabolic profiles. 相似文献
99.
Ivan Gutman Milan Randić Alexandru T. Balaban Boris Furtula Veselin Vuĉković 《Polycyclic Aromatic Compounds》2013,33(3):215-226
Abstract Recently three methods for calculating the π-electron content of rings of benzenoid hydrocarbons were put forward: one based on the consideration of Kekuléstructural formulas, and the other two based on an analogous treatment of the Clar aromatic sextet formulas. These three methods are applied to the homologous series consisting of two condensed acene chains (whose first members are pyrene, anthanthrene, peri-naphthacenonaphthacene, …), leading to basically identical results. In contrast to acenes (in which the partition of π-electrons into rings is uniform), in the double-hexagonal-chain species the partition of π-electrons is highly non-uniform. The electron content monotonically decreases, in opposite directions, along the two acene chains, being maximal in the least annelated rings. Some other generally valid regularities in the π-electron properties of the double–hexagonal–chain benzenoids are also pointed out. 相似文献
100.
三个复杂基本运动链奇异性条件的求解与识别 总被引:4,自引:0,他引:4
提出了求解任意复杂多回路平面连杆机构及操作手奇异位置分析的模块法。即对组成复杂机构的数量有限的基本运动链进行奇异分析 ,推导出这些复杂基本运动链产生奇异位置构型的奇异性条件 ,然后将之看作是复杂机构和操作手奇异分析的基本模块 ;只要一个基本运动链达到奇异位置时 ,该复杂机构即处于奇异位置。在此基础上本文又推导出三个复杂基本运动链产生奇异位置构型的奇异性条件 ,从而扩展了用该方法求解复杂多回路平面连杆机构及操作手奇异位置的应用范围。 相似文献