Uma avaliação comparativa de estratégias de arranjos físicos para estaleiros de construção de embarcações metálicas de pequeno porte

The present study aims to analyse, in different levels of demand, what is the best layout strategy to adopt for the small metallic shipbuilding. To achieve this purpose, three simulation models are developed for analyze these production strategies under the positional, cellular and linear layouts. By the use of a simulation tool for compare the scenarios, Chwif and Medina (2010) and Law (2009)´s methodologies were adapted that includes three phases: conception, implementation and analysis. In conception real systems were represented by process mapping according to time, material resources and human resources variables required for each step of the production process. All of this information has been transformed in the cost variable. Data were collected from three different production systems, two located in Natal RN with cellular and positional layouts and one located in Belém-PA with linear layout. In the implementation phase, the conceptual models were converted in computacional models through the tool Rockwell Software Arena ® 13.5 and then validated. In the analysis stage the production of 960 ships in a year vessels were simulated for each layout noting that, for a production of until 80 units positional layout is the most recommended, between 81 and 288 units the cellular layout and more than 289 units the linear layout

Controle de Manipulador Redundante Utilizando Realimentação Visual

In conventional robot manipulator control, the desired path is specified in cartesian space and converted to joint space through inverse kinematics mapping. The joint references generated by this mapping are utilized for dynamic control in joint space. Thus, the end-effector position is, in fact, controlled indirectly, in open-loop, and the accuracy of grip position control directly depends on the accuracy of the available kinematic model. In this report, a new scheme for redundant manipulator kinematic control, based on visual servoing is proposed. In the proposed system, a robot image acquired through a CCD camera is processed in order to compute the position and orientation of each link of the robot arm. The robot task is specified as a temporal sequence of reference images of the robot arm. Thus, both the measured pose and the reference pose are specified in the same image space, and its difference is utilized to generate a cartesian space error for kinematic control purposes. The proposed control scheme was applied in a four degree-of-freedom planar redundant robot arm, experimental results are shown

O adolescente em conflito com a lei e a escola: criminalização e inclusão perversa

This study aims to identify the relation between adolescents in conflict with the penal law, who were convicted to assisted freedom (a socio-educative measure applied by the Juvenile Justice system as a sanction to adolescent offenders), and the school. The research was developed in the Community-based Assisted Freedom Program of Pastoral do Menor , in Fortaleza (capital city of Ceará State, Brazil). The study has engaged 21 adolescents, eight program professionals, three members of the Center for Defense of Child Rights in Ceará, five teachers and eight school principals and education managers from the schools attended by the adolescents in the neighborhoods of Pirambu, Tancredo Neves, Jardim Iracema e Bom Jardim. It intends, based on dialectical and historical method, to define the investigated adolescents as persons with a very singular insertion into the social structures of neoliberal capitalism. Their adolescence is subject to consumerism appeals, to the limits imposed by these appeals and to perverse ways of insertion in the system, such as criminalization, segregation and marginalization. It reveals that the school attended by the adolescents reproduces such conditions of insertion. At the same time, these conditions are elements of identity, by which the adolescents are characterized.