A general graphical user interface for automatic reliability modeling

Reported here is a general Graphical User Interface (GUI) for automatic reliability modeling of Processor Memory Switch (PMS) structures using a Markov model. This GUI is based on a hierarchy of windows. One window has graphical editing capabilities for specifying the system's communication structure, hierarchy, reconfiguration capabilities, and requirements. Other windows have field texts, popup menus, and buttons for specifying parameters and selecting actions. An example application of the GUI is given

El concepto de comunidad en las ciencias sociales latinoamericanas: apuntes para su comprensión

Este trabajo gira alrededor del concepto de "comunidad". En primer lugar se aborda el tratamiento que Tönnies, Durkheim y Weber realizaron de la tensión comunidad/sociedad. En segundo lugar, se refieren algunas tesis de Mariátegui y Flores Magón. Más adelante, se intenta relacionar el concepto de "comunidad" con el "modernidad". Posteriormente, se muestran dos facetas posibles de las relaciones entre las comunidades campesinas y la acumulación capitalista. Finalmente se arriesgan algunas hipótesis acerca de la utilización del concepto de "comunidad" en América Latina.Fil: Liceaga, Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Mendoza. Instituto de Ciencias Humanas, Sociales y Ambientales; Argentin

Automatic specification of reliability models for fault-tolerant computers

The calculation of reliability measures using Markov models is required for life-critical processor-memory-switch structures that have standby redundancy or that are subject to transient or intermittent faults or repair. The task of specifying these models is tedious and prone to human error because of the large number of states and transitions required in any reasonable system. Therefore, model specification is a major analysis bottleneck, and model verification is a major validation problem. The general unfamiliarity of computer architects with Markov modeling techniques further increases the necessity of automating the model specification. Automation requires a general system description language (SDL). For practicality, this SDL should also provide a high level of abstraction and be easy to learn and use. The first attempt to define and implement an SDL with those characteristics is presented. A program named Automated Reliability Modeling (ARM) was constructed as a research vehicle. The ARM program uses a graphical interface as its SDL, and it outputs a Markov reliability model specification formulated for direct use by programs that generate and evaluate the model

Towards automatic Markov reliability modeling of computer architectures

The analysis and evaluation of reliability measures using time-varying Markov models is required for Processor-Memory-Switch (PMS) structures that have competing processes such as standby redundancy and repair, or renewal processes such as transient or intermittent faults. The task of generating these models is tedious and prone to human error due to the large number of states and transitions involved in any reasonable system. Therefore model formulation is a major analysis bottleneck, and model verification is a major validation problem. The general unfamiliarity of computer architects with Markov modeling techniques further increases the necessity of automating the model formulation. This paper presents an overview of the Automated Reliability Modeling (ARM) program, under development at NASA Langley Research Center. ARM will accept as input a description of the PMS interconnection graph, the behavior of the PMS components, the fault-tolerant strategies, and the operational requirements. The output of ARM will be the reliability of availability Markov model formulated for direct use by evaluation programs. The advantages of such an approach are (a) utility to a large class of users, not necessarily expert in reliability analysis, and (b) a lower probability of human error in the computation

Induction motor control: multivariable analysis and effective decentralized control of stator currents for high performance applications

Adequate control of the stator currents is a fundamental requirement for several high-performance induction motor (IM) control schemes. In this context, classical linear controllers remain widely employed due to their simplicity and success in industrial applications. However, the models and methods commonly used for control design lack valuable information –which is fundamental to guarantee robustness and high performance. Following this line, the design and existence of linear fixed controllers is examined using individual channel analysis and design. The studies here presented aim to establish guidelines for the design of simple (time-invariant, low order, stable, minimum-phase and decentralized), yet robust and highperformance linear controllers. Such characteristics ease the implementation task and are well suited for engineering applications, making the resulting controllers a good alternative for the stator currents control required for high-performance IM schemes; e.g., field oriented, passivity-based and intelligent control. Illustrative examples are presented to demonstrate the analysis and controller design of an IM, with results validated in a real-time experimental platform. It is shown that it is possible to completely decouple the stator currents subsystem without the use of additional decoupling elements

A Geometric Control System with Applications to Helicopters

This thesis introduces an Automatic Flight Control System for single rotor helicopters which gives a new relevance to the traditional techniques based on the Linear Control Theory. This design was obtained by applying concepts of differential geometry tailored for engineering purposes through the Nonlinear System Theory. The development of this thesis follows the traditional path of applied sciences. First the need to establish techniques for theoretical analysis of flight machanics, where the small disturbance methods are no longer valid, is reviewed. This is followed by a presentation of the nonlinear problem and a survey of the development of the theoretical tools available. At this stage the process, a single rotor helicopter, is modelled. The model is then cast in a form suitable for Nonlinear System Theory techniques. Next, the mathematical theory to be applied is fully developed. It consists of finding the conditions required by a nonlinear system to be transformable under state feedback to a linear canonical form; the construction of the feedback is also presented. A Flight Control System is designed by applying this theory to the helicopter model previously formulated. The above application requires the development of Symbolic Algebraic Manipulation programmes, which are also included. Finally, a set of simulation studies demonstrate the performance of the design

FTMP (Fault Tolerant Multiprocessor) programmer's manual

The Fault Tolerant Multiprocessor (FTMP) computer system was constructed using the Rockwell/Collins CAPS-6 processor. It is installed in the Avionics Integration Research Laboratory (AIRLAB) of NASA Langley Research Center. It is hosted by AIRLAB's System 10, a VAX 11/750, for the loading of programs and experimentation. The FTMP support software includes a cross compiler for a high level language called Automated Engineering Design (AED) System, an assembler for the CAPS-6 processor assembly language, and a linker. Access to this support software is through an automated remote access facility on the VAX which relieves the user of the burden of learning how to use the IBM 4381. This manual is a compilation of information about the FTMP support environment. It explains the FTMP software and support environment along many of the finer points of running programs on FTMP. This will be helpful to the researcher trying to run an experiment on FTMP and even to the person probing FTMP with fault injections. Much of the information in this manual can be found in other sources; we are only attempting to bring together the basic points in a single source. If the reader should need points clarified, there is a list of support documentation in the back of this manual

Diseño y Despliegue de arquitectura para la recogida y presentación de medidas de sensores IoT

Actualmente, un número creciente de dispositivos y equipos se conectan a Internet, cada vez es más común encontrarse con sensores que envían información a través de la red o empresas que quieren monitorizar su producción remotamente. Por ello, en la Industria 4.0 y en el ámbito de las Smartcities es cada vez más importante la recogida de los datos de sensores del denominado IoT. Debido a ello, en este contexto, este Trabajo Fin de Master (TFM) propone un diseño de una arquitectura que permita recoger y almacenar los datos de sensores IoT de diversos ámbitos, comerciales e industriales, y proporcione herramientas para una presentación sencilla y comprensible por cualquier usuario de estos datos. Adicionalmente en este documento se analizará la viabilidad de esta arquitectura mediante el diseño y la implementación de una maqueta, que haga uso de este diseño utilizando algunas de las tecnologías que comienzan a cobrar importancia en el ámbito del IoT.Nowadays a growing number of devices and equipment connect to the Internet; it is increasingly common to find sensors that send information through the network or companies that want to monitor their production remotely. For this reason, in the Industry 4.0 and in the scope of Smartcities, it is increasingly important to collect the data of sensors of the so-called IoT. Because of this, in this context, this End of Master work proposes an architecture design that allows the gathering and storage of IoT sensor data from various commercial and industrial environments, and provides tools for a simple and comprehensible presentation of the data for any user. Additionally, in this document will be analysed the feasibility of this architecture, through the design and implementation of a model that makes use of this design by means of some of the technologies that begin to acquire importance in the scope of the IoT.Gaur egun, gailu eta ekipo kopuru handiagoa konektatzen da Internetera, gero eta ohikoagoa da topatzea sarearen bidez informazioa bidaltzen duten sentsoreekin edo urrunetik haien ekoizpenaren jarraipena egin nahi duten enpreseekin. Ondonoz, 4.0 Industrian eta Smartcity-en eremuan gero eta garrantzitsuagoa da IoT sentsoreen datuen bilketa. Hori dela eta, testuinguru honetan, Master Amaierako Lan (MAL) honek eremu ezberdinetako (komertziala eta industriala) IoT sentsoreen datuen bilketa eta biltegiketa ahalbideratzen diseinu honek tresna ezberdinak eskaini behar ditu edozein erabiltzailek datu horitako aurkezpen soil eta ulergarria jaso dezan. Horrez gain, dokumento honetan arkitektura honen bideragarritasuna aztertuko da. Horretarako diseinu hau erabiltzen duen maketa bat diseinatu eta garatuko da, IoT eremuan gero eta garrantzi handiago duten teknologiak erabiliz