Uncertainty relation for chaos

A necessary condition for the emergence of chaos is given. It is well known that the emergence of chaos requires a positive exponent which entails diverging trajectories. Here we show that this is not enough. An additional necessary condition for the emergence of chaos in the region where the trajectory of the system goes through, is that the product of the maximal positive exponent times, the duration in which the system configuration point stays in the unstable region should exceed unity. We give a theoretical analysis justifying this result and a few examples. We stress that the criterion suggested involves only local exponents and is not concerned with asymptotic defined exponents.

Lexical Configuration in Adhan: a Semantic Perspective

Adhan is defined as the Islamic call for announcing the time of Salah (practice of formal worship in Islam) which is recited by muezzin at mosques. This study aims to explore adhan from a lexical configuration point of view which has been introduced by English linguist Cruse (1986). As an initial step, lexical configuration of Cruse (1986) is explained from lexical semantic point of view. Hierarchy, then is defined which is a set of elements related to one another in a characteristic way according to Cruse (1986). After elaborating on hierarchical chain of meaning in lexical semantics, the adhan text with transliteration and English meaning is provided. Analyzing adhan from the semantic view point of Cruse (1986) confirms that adhan is the symbol of Islamic belief and ideology. It is not a static chain of words but a dynamic melody that invites people to move to worship Allah. It also reports that worshipping Allah needs a movement toward Him and also moving toward Allah needs The Facilitator or the Leader who is aware of the howness of the moving that can show Allah's order and path to people. The Facilitator is Prophet Mohammad (P. B. U. H.) who shows the path of Salvation and Good Deeds. Based on Islamic philosophy, one can reach to Allah by means of Salah. Also, one will reach to Allah by doing what Allah says. This study also introduces a new hierarchy to broaden the lexical configuration proposed by Cruse (1986) as circular hierarchy.

Overview of Some Non –Neural Network Methods for Fitting Ab Initio Potential-Energy Databases

In this chapter, we describe results obtained by five methods that have been employed to fit ab initio potential-energy. These methods are (i) moving or modified Shepard interpolation (MSI), (ii) interpolative moving least squares (IMLS), (iii) invariant polynomials (IP), (iv) reproducing kernel Hilbert space (RKHS), and (v) a hybrid method that combines MSI and IMLS methods. The MSI and IMLS methods are described in some detail in the following. The IP and RKHS procedures are significantly more complex, and the reader is referred to the original papers for a more complete discussion of the details by which these methods are executed. The moving or modified Shepard interpolation (MSI) method was developed primarily by Collins and co-workers. The method employs electronic structure calculations to obtain the molecular potential energy at configuration points generated by an automated procedure. These data are then employed in a Shepard interpolation procedure to obtain the potential energies of the system at points other than those in the database. This procedure involves expressing the local potential about each configuration point in a Taylor series expansion. The term “moving” in the title derives from the fact that the set of internal coordinates employed in the interpolation varies from point-to-point in the database. Like all fitting methods, the MSI procedure requires the potential energy at a set of configuration points in the (3N-6) dimensional internal space of the system under investigation. These energies are generally obtained using ab initio electronic structure methods at some level of accuracy. In addition to the potential energies at each configuration point, the method also requires at least the first and second derivatives of the potential with respect to the coordinates being employed at each configuration point. These derivatives are needed to allow the local potential about a given configuration point in the database to be expressed in terms of a Taylor series expansion about that point. In principle, the MSI method may be extended to include third or fourth derivatives, but in most applications, the expansions are truncated after the quadratic terms.

SOBRE PROBLEMAS DE IDENTIDADE E EMOÇÕES NO ESPORTE E NO LAZER: COMENTÁRIOS CRÍTICOS E CONTRA-CRÍTICOS SOBRE AS SOCIOLOGIAS CONVENCIONAL E CONFIGURACIONAL DE ESPORTE E LAZER

O presente artigo trata da análise sociológica que as emoções despertam no esporte e no lazer e em suas instituições. Desenvolve uma análise teórica a partir da abordagem eliseana de configuração, em especial a teoria de “processos civilizatórios”. On problems of identity and the emotions in sport and leisure: critical and counter-critical comments on the conventional and figurational sociologies of sport and leisure Abstract This article deals with the sociological analysis of the emotions arisen in sport and leasure and their institutions. It develops a theoretical analysis from the elisean configuration point of view, especially with regard to the “civilizing processes”.

Solving the motion planning problem by using neural networks

SUMMARYThis paper presents a new neural networks-based method to solve the motion planning problem, i.e. to construct a collision-free path for a moving object among fixed obstacles. Our ‘navigator’ basically consists of two neural networks: The first one is a modified feed-forward neural network, which is used to determine the configuration space; the moving object is modelled as a configuration point in the configuration space. The second neural network is a modified bidirectional associative memory, which is used to find a path for the configuration point through the configuration space while avoiding the configuration obstacles. The basic processing unit of the neural networks may be constructed using logic gates, including AND gates, OR gates, NOT gate and flip flops. Examples of efficient solutions to difficult motion planning problems using our proposed techniques are presented.

Dynamic direct subspaces for robot path planning

SUMMARYA direct subspace of a dynamic three-dimensional joint space is found to be useful for robot path planning in workspaces comprised of both static and dynamic objects. Dynamic descriptions permit positioning tables, automated guided vehicles, conveyors and cycling machine tools to be modeled by elements which translate or cycle along rectilinear paths. Graphical path planning procedures use cursor indicators to move the robot configuration point between the desired starting and final configurations while avoiding both the static and dynamic joint space obstacles.