Exact Sciences

The quest to provide a fundamental understanding and explanation of reality is an ambitious one. Perhaps it is too ambitious. The possible restrictions for such an enterprise to be successful must be inquired in order to determine the issue. Section 1 explores one’s understanding in reaching (scientific) conclusions: to what extent does a successful account testify to understanding? Section 2 focuses on the other side of such an account: does it provide an explanation in a more fundamental sense than pointing out causes of phenomena, or is it restricted to such a task? A critical stance vis-à-vis the (scientific) enterprise of unearthing reality’s structure remains necessary in order not to confuse a consistent and productive theory with one that demonstrates an understanding and explanation in the sense of this article.

Este artigo apresenta uma a avaliacao dos riscos ergonomicos, em membros superiores, para postos de tornearia leve e pesada do setor de usinagem de uma industria de medio porte, do setor metalurgico, dedicada a fabricacao de conexoes em aco para o setor petrolifero, localizada no municipio de Guarulhos, SP. Existem varios instrumentos para analise ergonomica. Cada um deles possui caracteristicas e peculiaridades que tornam uns mais apropriados do que outros para determinadas aplicacoes. Este trabalho aplicara dois protocolos de analise de riscos: Protocolo de Couto, que e um procedimento para avaliacao de riscos ergonomicos em membros superiores e o Protocolo Strain index que avalia riscos ergonomicos em extremidades distais dos membros superiores. Os resultados desta pesquisa contribuem para orientar os profissionais envolvidos com ergonomia sobre adequacao desses dois Protocolos a determinadas analises sujeitas a riscos ergonomicos.

This article presents the results of a broader research project which aims to argue for the normativity of scientific laws. Usually scientific laws are regarded as descriptive, which contrasts them to prescriptive norms. To show their normativity, I utilize the logical account of explicitly normative systems by Carlos Alchourrón and Eugenio Bulygin (1971). I identify the characteristic elements of norma-tivity and analyse accounts of implicit normativity in science using those terms to show the affinities of explicit and implicit normativities. The research project continues with the substantiation of the norma-tivity of scientific laws in detail and the results will be presented in Normativity of Scientific Laws (II) (Mets 2018).

Se intenta reflejar la disponibilidad de las tesis y trabajos equivalentes para acceder a títulos de grado y de postgrado en las Facultades de Ingeniería y de Ciencias Exactas y Naturales de la Universidad de Buenos Aires (UBA), así como las posibilidades de acceso a dichos documentos. Se analizan algunas características particulares de las tesis presentadas en las mencionadas facultades, como una aproximación a las conductas informativas de ingenieros y científicos = The availability of thesis and equivalent works aimed to obtain graduate or postgraduate degrees in the Facultad de Ingeniería and the Facultad de Ciencias Exactas y Naturales of the Universidad de Buenos Aires (UBA), and the possibilities of accessing those documents is tried to be shown here. Some particular characteristics of the thesis are analyzed as an approach to the information behavior of engineers and scientists.

The objective of the present work is to present a proposal of computer system for verification of the state of operation of escalator through communication without thread. The computer system proposed in this work it is composed of an interface installed directly in the panel of control of the escalator with the objective of collecting information that allow to identify the state of operation of those equipments and to transmit them for a remote computer through a net structure without thread built under the pattern Bluetooth. The proposed system makes possible that the periodic inspection of the operation state is made without the interruption of the service to the public, which only happens when the reading of data informs some non conformity or in periods established by the manufacturer, for change of pieces for fatigue. In that way, it is made possible a quality earnings and productivity of the maintenance teams, which can accomplish a larger amount of inspections with smaller t...

The objective of the present work is to present a proposal of computer system for verification of the state of operation of escalator through communication without thread. The computer system proposed in this work it is composed of an interface installed directly in the panel of control of the escalator with the objective of collecting information that allow to identify the state of operation of those equipments and to transmit them for a remote computer through a net structure without thread built under the pattern Bluetooth. The proposed system makes possible that the periodic inspection of the operation state is made without the interruption of the service to the public, which only happens when the reading of data informs some non conformity or in periods established by the manufacturer, for change of pieces for fatigue. In that way, it is made possible a quality earnings and productivity of the maintenance teams, which can accomplish a larger amount of inspections with smaller t...

Pode-se afirmar com seguranca que as baterias, tanto as celulas primarias, como as celulas secundarias sao a forma mais popular de armazenamento de energia e sua aplicacao vem aumentando de forma significativa ao longo das ultimas decadas, estando ainda longe de alcancar o seu apice. Apesar da crescente aplicacao das baterias e do montante dos negocios envolvidos nesta area os cursos de engenharia eletrica ainda nao oferecem cursos voltados para a aplicacao de baterias. O objetivo deste artigo e apresentar uma resenha envolvendo os principais conceitos que abrangem o tema sem a profundidade requerida por um fisico, quimico ou engenheiro de materiais, mas que sejam suficientes para que o Engenheiro Eletricista seja capaz de acompanhar as principais novidades tecnologicas na area; especificar corretamente uma bateria para uma dada aplicacao e entender e vislumbrar novas aplicacoes para esses dispositivos.

As mesas de coordenadas XY ou XYZ sao bastante utilizadas em tarefas de posicionamento de pecas a serem usinadas, medidas, ou no posicionamento de ferramentas para tarefas de usinagem, pintura, soldagem, etc. Basicamente existem duas classes de mesas de coordenadas, as acionadas por motor de passo que em sua maioria trabalham sem realimentacao, e as acionadas por motor de corrente continua ou de inducao que trabalham com realimentacao. A execucao de uma operacao de medicao ou de usinagem com mesas de coordenadas exige que o erro de posicionamento seja o minimo possivel, de preferencia nulo, para garantir bons resultados. Este trabalho tem como objetivo o projeto de controladores LQG ( Linear Quadratico Gaussiano) e Proporcional Derivativo usando tecnicas de controle robusto, para uma mesa de coordenadas XY. Resultados simulados sao apresentados visando avaliar o desempenho da mesa de coordenadas sob as acoes dos controladores. Palavras-chaves. Mesa de coordenadas, controlador LQG, C...