In this paper, we investigate the notion of transformation modules as a structuring principle for the speciication of graph transformation systems which provide a collection of operations on graphs. Based on the notion of transformation units, a concept that allows to specify binary relations on graphs, a transformation module consists of a set of transformation units. To be able to distinguish...

abstract the muskingum method is frequently used to route floods in hydrology. however, application of the model is still difficult because of the parameter estimation’s. recently, some of heuristic methods have been used in order to estimate the nonlinear muskingum model. this paper presents a efficient heuristic algorithm, simulated annealing, which has been used to estimate the three paramet...

Industry clusters have been the focus of scholars and governments since the second half of the 20th century. During a cluster’s growing process, the government plays an important role. In order to show the growing law of the clusters and how government did for co-agglomeration, we proposed two kinds of models: Logistic model and BA model with parameter α to describe the single and mass clusters...

When data are poor, we resort to theory modeling. This is a two-step process. We have first to identify the appropriate type of model for the system under consideration and then to tailor it to the specifics of the case. To understand settlement formation, which is the concern of this article, this involves choosing not only input parameter values such as site separations but also input functio...

In this paper, the problem of identifying a predictor model for an unknown system is studied. Instead of standard models returning a prediction value as output, we consider models returning prediction intervals. Identification is performed according to some optimality criteria, and, thanks to this approach, we are able to provide, independently of the data generation mechanism, an exact evaluat...

ionospheric slab thickness is defined as the ratio of tec to maximum electron density of the f-region (nmf2), proportional to the square of the f2-layer critical frequency (fof2). it is an important parameter in that it is linearly correlated with scale height of the ionosphere, which is related to electron density profile. it also reflects variation of the neutral temperature. therefore, ionos...

Welch & Peers (1963) used a root-information prior to obtain posterior probabilities for a scalar parameter exponential model and showed that these Bayes probabilities had the confidence property to second order asymptotically. An important undercurrent of this indicates that the constant information reparameterization provides location model structure, for which the confidence property ...

wepp model needs a great deal of input data.  identifying the model’s sensitive parameters and their prioritization increases the accuracy and efficiency of the model. on the other hand, wepp model can simulate processes affecting on runoff, erosion and sediment throughout the year. thus, model sensitivity must vary based on the storm occurrence time and parameters value in different sections o...