Increasing interest in studying community structures, or clusters in complex networks arising in various applications has led to a large and diverse body of literature introducing numerous graph-theoretic models relaxing certain characteristics of the classical clique concept. This paper analyzes the elementary clique-defining properties implicitly exploited in the available clique relaxation models and proposes a taxonomic framework that not only allows to classify the existing models in a systematic fashion, but also yields new clique relaxations of potential practical interest. Some basic structural properties of several of the considered models are identified that may facilitate the choice of methods for solving the corresponding optimization problems. In addition, bounds describing the cohesiveness properties of different clique relaxation structures are established, and practical implications of choosing one model over another are discussed. 相似文献
Abstract We are interested in the control problem of a partially observable diffusion process, which is initialized at a fixed point of ?n, and we want to characterize the associated value function. To resort to the theory of viscosity solutions depends on the possibility to translate such a problem on Hilbert spaces like L2(?n), and so it can not be used here. Nevertheless, a result of N. Bouleau and F. Hirsch allows us to introduce a broadened problem which fulfills the condition. The fact remains to link these two control problems. 相似文献
On a compact Riemannian manifold,we prove a decomposition theorem for arbitrarily bounded energy sequence of solutions of a singular elliptic equation. 相似文献
A self-consistent approach is used to estimate the internal stresses induced by moisture absorption in composite materials with a viscoelastic matrix and linear elastic fibers. A strong influence of the behavior of the viscoelastic matrix and humidity on the internal stresses in the structures at macroscopic and local scales is found to exist. 相似文献
Journal of Solid State Electrochemistry - In this paper, we study systematically the effect of ball/powder weight ratio on the morphological, structural, and electrochemical properties of... 相似文献
Polymer mechanics and characterization is an active area of research where a keen effort is directed towards gaining a predictive and correlative relationship between the applied loads and the specific conformational motions of the macromolecule chains.
Objective
Therefore, the objective of this research is to introduce the preliminary results based on a novel technique to in situ probe the mechanical properties of polymers using non-invasive, non-destructive, and non-contact terahertz spectroscopy.
Methods
A dielectric elastomer actuator (DEA) structure is used as the loading mechanism to avoid obscuring the beam path of transmission terahertz time-domain spectroscopy. In DEAs, the applied voltage results in mechanical stresses under the active electrode area with far-reaching stretching in the passive area. Finite element analysis is used to model and simulate the DEA to quantify the induced stresses at the observation site over a voltage range spanning from 0 V to 3000 V. Additionally, a novel analysis technique is introduced based on the Hilbert-Huang transform to exploit the time-domain signals of the ultrathin elastomeric film and to defy the limits set forth by the current state-of-the-art analysis techniques.
Results
The computational result shows a nonlinear relationship between the effective stresses and the applied voltage. Analysis of the terahertz time-domain signals shows a shift in the delay times and a decrease in signal peak amplitudes, whereas these characteristics are implicitly related to the change in the index of refraction.
Conclusions
In all, the results evidentially signify the interrelationship between the conformational changes and applied mechanical stress.
This paper deals with some perturbation of the so-called generalized prescribed scalar curvature type equations on compact Riemannian manifolds; these equations are nonlinear, of critical Sobolev growth, and involve the p-Laplacian. Sufficient conditions are given to have multiple positive solutions. 相似文献
In this paper, We study a general class of nonlinear degenerated elliptic problems associated with the differential inclusion β(u)-div(a(x, Du)+ F(u)) ■ f in Ω, where f ∈ L1 Ω. A vector field a(·,·) is a Carath′eodory function. Using truncation techniques and the generalized monotonicity method in the functional spaces we prove the existence of renormalized solutions for general L1-data. Under an additional strict monotonicity assumption uniqueness of the renormalized solution is established. 相似文献