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Despite the numerous prerogatives of the Exchequer, as regards fiscal execution, is the Executive title from tax debt or not, guaranteed by law n° 6.830, 22 September 1980, and its subsequent amendments, the runs, or debtor faced often in difficulty during his defense. Whether in the formal aspect of the summons, garnishment and exactly the resources used by the undo the procedure enforceable. In this context, more specifically, highlight the difficulty in establishing what the limits of the allegations made by the debtor in the new embargoes after the correction or replacement of the Active Debt Certificate. From divergent views, one realizes the importance of the topic. [ABSTRACT FROM AUTHOR]

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare condition that occurs normally in the anterior maxilla of infants aged <1 year. The use of clinical and imaging tools for MNTI is extremely important to prevent problems with function as well as the aesthetic features in a breastfeeding child. Brazil is a multiethnic country with a poor epidemiological policy and little data to track the incidence of certain diseases, including MNTI. It is important to study this pathology with ethnicity as a factor to improve the current epidemiological programs and establish better post-treatment management. This paper describes a case of a 2-month-old male of African-indigenous descent and Brazilian Amazon residency, who presented to our unit in 2009 with a history of an expanding mass involving the anterior maxilla. Clinical and computerized tomography scans were used to diagnose the mass as MNTI, which was removed by total excision. A biopsy later confirmed the MNTI diagnosis. [ABSTRACT FROM AUTHOR]

This paper presents a heuristic constructive algorithm (HCA) for optimal capacitor placement on distribution systems. This is a nonlinear mixed integer optimization problem. In the proposed approach, the integer variables are represented using sigmoid function, thus interior point optimal power flow formulation can be applied to obtain sensitivity indexes based on Lagrange multipliers, reactive power, and bus voltage. The methodology is applied to two power distribution systems, and the results are compared with those obtained using. a genetic algorithm approach. [ABSTRACT FROM AUTHOR]

This paper presents a new approach for distribution system reconfiguration (DSR) based on optimum power flow (OPF) in which the branch statuses (open/close) are represented by continuous functions. In the proposed approach, all branches are initially considered closed, and from the OPF results, a heuristic technique is used to determine the next loop to be broken by opening one switch. Then the list of switches that are candidates to be opened is updated, and the above process is repeated until all loops are broken, making the distribution system radial. This paper includes results and comparisons on test systems utilized in three classical papers published in the technical literature, as well as in a previous paper by the authors. Results obtained on a real large-scale distribution system are also presented. [ABSTRACT FROM AUTHOR]

This paper presents a reconfiguration algorithm that is specially suited to large-scale distribution systems. The algorithm uses a heuristic strategy that starts with the system in a meshed status, with all maneuverable switches closed. The choice of the switches to be opened is based on the calculation of the minimum total system losses, using a load-flow program. A refinement on this procedure, based on branch status exchange, is described. The paper includes results and comparisons on test systems utilized in three classical papers published in the technical literature. Results obtained on a real large-scale distribution system are also presented. [ABSTRACT FROM AUTHOR]

• Investigation of vibration attenuation in a finite array of symmetric/asymmetric periodic rods. • Analytical expressions derived to predict the behaviour of N periodic cells. • Determination of simple expressions to estimate the attenuation band and the minimum transmissibility within this band. • Demonstration that a correctly orientated finite array of asymmetric cells outperforms the a comparable array of symmetric cells in terms of both bandwidth and minimum transmissibility. • Theoretical analysis is supported with experimental results. Periodic structures have an important role to play in the reduction of vibration within a targeted frequency range. Much of the literature concerning vibrations in periodic structures involves the description of wave behaviour in infinite structures. This paper concerns the dynamic behaviour of a finite mono-coupled periodic structure, concentrating on the prediction of the vibration transmission through the complete structure in terms of the displacement transmissibility of a single cell. An investigation is conducted into the effects of either using an array of symmetric or asymmetric cells comprised of rods, on the lowest frequency range targeted for vibration attenuation. The importance of the orientation of asymmetric cells with respect to the source is also discussed. Analysis of the systems shows that correctly orientated asymmetric cells offer better performance than an array of symmetric cells for a finite mono-coupled periodic structure. Provided that the periodic structure is not connected to a structure that significantly affects its dynamics, there is improved performance both in terms of a wider frequency range in which there is vibration attenuation, and the maximum vibration attenuation within this frequency range. Analytical expressions are derived that allow the prediction of the maximum attenuation within the attenuation band based on the number of symmetric or asymmetric cells. Some experimental work is also presented to support the theoretical predictions. [ABSTRACT FROM AUTHOR]

Describes a thermal model designed to determine the ampacity derating of electric cables in wrapped trays. Heat transfer coefficient of natural convection; Effective thermal conductivity of the cable mass; Insulated conductors; Thermophysical properties; Sensitivity analysis; Thermal influences.

This work presents a new formulation for the power flow problem, with explicit representation of the neutral conductor and grounding. This methodology has been named the four-conductor current injection method (FCIM). The Newton-Raphson method is applied to solve the set of nonlinear current injection equations that are derived using phase coordinates, and the complex variables are written in rectangular form. The proposed algorithm can be used to analyze both balanced and unbalanced systems, meshed or radial, with controls and distributed generation, and is shown to be very efficient and robust for large scale systems. [ABSTRACT FROM AUTHOR]

It is well known that the accuracy of frequency-dependent line models in time-domain calculations relies on the equations that define the line propagation matrix H and characteristic admittance Yc. Therefore both modal-domain and phase-domain transmission line models are affected by the assumptions in the evaluation of the series impedance Z, namely, the formulation of the internal conductor and the ground return impedance. The complexities of the exact representation of these parameters have led investigators to propose approximate formulae, and several of these are available in the technical literature. This work examines the effects of these formulae on the calculation of matrices H and Yc on the time-domain responses of the line. Several possibilities have been tested. The results show that although the approximate methods can be used for overhead lines, caution is needed for underground cable systems. [ABSTRACT FROM AUTHOR]

Presents the development of mathematical models for thyristor controlled series compensator for voltage regulator devices and for remote bus voltage control that are suitable to be used with the three-phase current injection method for power flow calculation. Methods of the study; Results and discussion; Conclusion.

This letter describes a new voltage controlled bus (PV bus) representation in connection with the three-phase current injection method-TCIM of power flow analysis. This representation requires an augmented system of linearized equations to incorporate the reactive power as a dependent variable. Tests and comparisons between the former and the new approach are described and the improved stiffness of this new proposition is demonstrated. [ABSTRACT FROM AUTHOR]

There are two fundamental strategies in the design of metamaterials used for noise and vibration control. The first uses structural periodicity and explores the Bragg scattering to produce frequency ranges where waves do not propagate or are severely attenuated (stop-bands). This condition is usually limited by the constitutive size of the structural elements and tends to occur at higher frequencies. A second strategy consists of adding vibration absorbers to produce a resonance(s), and this can occur at much lower frequencies. The addition of periodically attached vibration absorbers alone creates a periodic medium, and Bragg stop-bands also occurs in this situation. There is a particular condition where the Bragg and local resonance stop-bands can be combined to produce an ultra-wide or a super stop-band. This paper investigates the conditions required to produce a super stop-band in a finite mono-coupled periodic system composed of symmetric cells, each with a vibration absorber attached. Using a lumped parameter system, the dynamic features and the transmissibility of a single cell are determined, and the physical mechanisms behind the super stop-band formation are investigated, including the absorber tuning frequency and the influence of damping. Two experimental setups to support the theoretical findings are described. One involves a lumped-parameter system and the other involves a rod, both with a vibration absorber attached. The results show that a smooth super stop-band only occurs when the vibration absorber is tuned to the free-free natural frequency of the single host cell, creating a union between the Bragg stop-bands due to mass and stiffness of the absorber, and that the damping in the absorber should be equal to the damping in the host cell. [ABSTRACT FROM AUTHOR]

This paper presents an optimum power flow (OPF) modeling algorithm that uses the primal-dual interior point technique to determine the best investment strategy in the transmission line expansion problem. In the proposed method, the expansion decision (0 or 1) is mitigated by using a sigmoid function, which is incorporated in the OPF problem through the modified dc power flow equations. The investment decision is taken using a new heuristic model based on good sensitivity produced by the OPF results. Additionally, the transmission power losses are considered in the network model. The proposed methodology has been compared with methods available in the literature, using both a test system and an equivalent of the southeastern Brazilian system. [ABSTRACT FROM AUTHOR]