MgO/Ag(001) interface structure and STM images from first principles

The interface of MgO/Ag(001) has been studied with density functional theory applied to slabs. We have found that regular MgO films show a small adhesion to the silver substrate, the binding can be increased in off-stoichiometric regimes, either by the presence of O vacancies at the oxide film or by a small excess of O atoms at the interface between the ceramic to the metal. By means of theoretical methods, the scanning tunneling microscopy signatures of these films is also analyzed in some detail. For defect free deposits containing 1 or 2 ML and at low voltages, tunnelling takes place from the surface Ag substrate, and at large positive voltages Mg atoms are imaged. If defects, oxygen vacancies, are present on the surface of the oxide they introduce much easier channels for tunnelling resulting in big protrusions and controlling the shape of the image, the extra O stored at the interface can also be detected for very thin films.

Influence of Interface Surface Geometries In The Tensile Characteristics Of Friction Welded Joints From Aluminium Alloys

Friction welding is a solid state joining process that produces coalescence in materials, using the heat developed between surfaces through a combination of mechanical induced rubbing motion and applied load. In rotary friction welding technique heat is generated by the conversion of mechanical energy into thermal energy at the interface of the work pieces during rotation under pressure. Traditionally friction welding is carried out on a dedicated machine because of its adaptability to mass production. In the present work, steps were made to modify a conventional lathe to rotary friction welding set up to obtain friction welding with different interface surface geometries at two different speeds and to carry out tensile characteristic studies. The surface geometries welded include flat-flat, flat-tapered, tapered-tapered, concave-convex and convex-convex. A comparison of maximum load, breaking load and percentage elongation of different welded geometries has been realized through this project. The maximum load and breaking load were found to be highest for weld formed between rotating flat and stationary tapered at 500RPM and the values were 19.219kN and 14.28 kN respectively. The percentage elongation was found to be highest for weld formed between rotating flat and stationary flat at 500RPM and the value was 21.4%. Hence from the studies it is cleared that process parameter like “interfacing surface geometries” of weld specimens have strong influence on tensile characteristics of friction welded joints

A crack on the interface of piezo-electric bodies

Singularities of elastic and electric fields are investigated at the tip of a crack on the interface of two anisotropic piezo-electric media under various boundary conditions on the crack surfaces. The Griffith formulae are obtained for increments of energy functionals due to growth of the crack and the notion of the energy release matrix is introduced. Normalization conditions for bases of singular solution are proposed to adapt them to the energy, stress, and deformation fracture criteria. Connections between these bases are determined and additional properties of the deformation basis related to the notion of electric surface enthalpy are established.

Interface issues in the ESCHER visual database editor

Presentation at the 1997 Dagstuhl Seminar "Evaluation of Multimedia Information Retrieval", Norbert Fuhr, Keith van Rijsbergen, Alan F. Smeaton (eds.), Dagstuhl Seminar Report 175, 14.04. - 18.04.97 (9716). - Abstract: This presentation will introduce ESCHER, a database editor which supports visualization in non-standard applications in engineering, science, tourism and the entertainment industry. It was originally based on the extended nested relational data model and is currently extended to include object-relational properties like inheritance, object types, integrity constraints and methods. It serves as a research platform into areas such as multimedia and visual information systems, QBE-like queries, computer-supported concurrent work (CSCW) and novel storage techniques. In its role as a Visual Information System, a database editor must support browsing and navigation. ESCHER provides this access to data by means of so called fingers. They generalize the cursor paradigm in graphical and text editors. On the graphical display, a finger is reflected by a colored area which corresponds to the object a finger is currently pointing at. In a table more than one finger may point to objects, one of which is the active finger and is used for navigating through the table. The talk will mostly concentrate on giving examples for this type of navigation and will discuss some of the architectural needs for fast object traversal and display. ESCHER is available as public domain software from our ftp site in Kassel. The portable C source can be easily compiled for any machine running UNIX and OSF/Motif, in particular our working environments IBM RS/6000 and Intel-based LINUX systems. A porting to Tcl/Tk is under way.

Pi: A Parallel Architecture Interface for Multi-Model Execution

This thesis defines Pi, a parallel architecture interface that separates model and machine issues, allowing them to be addressed independently. This provides greater flexibility for both the model and machine builder. Pi addresses a set of common parallel model requirements including low latency communication, fast task switching, low cost synchronization, efficient storage management, the ability to exploit locality, and efficient support for sequential code. Since Pi provides generic parallel operations, it can efficiently support many parallel programming models including hybrids of existing models. Pi also forms a basis of comparison for architectural components.

An Immersed Interface Method for the Incompressible Navier-Stokes Equations in Irregular Domains

We present an immersed interface method for the incompressible Navier Stokes equations capable of handling rigid immersed boundaries. The immersed boundary is represented by a set of Lagrangian control points. In order to guarantee that the no-slip condition on the boundary is satisfied, singular forces are applied on the fluid at the immersed boundary. The forces are related to the jumps in pressure and the jumps in the derivatives of both pressure and velocity, and are interpolated using cubic splines. The strength of singular forces is determined by solving a small system of equations at each time step. The Navier-Stokes equations are discretized on a staggered Cartesian grid by a second order accurate projection method for pressure and velocity.

Disseny i projecte per a la construcció d’una màquina per a realitzar el tall a les castanyes

L’objecte del present projecte es el de realitzar el disseny per a la construcció d’una màquina per fer el tall de castanyes. Aquesta maquina inclourà la estructura, tolva d’alimentació, mecanisme de tall i sistema de seguretat. Un cop realitzat el tall a la castanya, aquesta serà evacuada per gravetat. L’alimentació dins la tolva i l’extracció del producte tallat es realitzarà manualment

Variables psicológicas en el control de interfaces cerebro-computadora.

Resumen tomado de la publicación

Automatització d’una màquina de tall rotatiu

Molt sovint, a l’indústria de l’alimentació o de la cosmètica, hi ha promocions on s’afegeixen productes de regal; aquests els embalen amb un sleever (tipus de plàstic força rígid) que després retractilen. Aquestes promocions solen ser esporàdiques i canviants i això fa que no sigui factible la modificació de la línia de producció general per a realitzar-les. Per aquest motiu, moltes empreses disposen d’una petita màquina de tall rotatiu per a poder tallar els sleevers ells mateixos, i així tallar a molta velocitat i precisió aquestes petites produccions. Així doncs, esdevé molt interessant l’adquisició d’aquest tipus de maquinària. L’objectiu del projecte és fer l’automatització d’una màquina que pugui tallar aquest tipus de material ràpidament per fer-lo rentable

Lecture 15 - Interface this

A quick word about abstract How a class interfaces Making Pets The Deadly Diamond of Death Interfaces (not interfaces)

Diseño de una interface entre un programa de cálculo simbólico y un programa CAD : aplicación al caso de modelado geométrico y modelado de caras.

El objetivo de este trabajo es el diseño de una interface entre un programa de cálculo simbólico y uno de CAD y su aplicación al caso de modelado geométrico y modelado de caras. El libro, se divide en tres capítulos: curvas en 2D, curvas en 3D y superficies. Dado que existen programas de cálculo simbólico que representan sus curvas, resultará favorable captar el fichero de puntos producido por dicho programa y, con los tratamientos convenientes, transformarlo en una lista susceptible de ser leída desde un programa CAD, los puntos trasvasados serán los vértices de una polilínea que posteriormente adaptada representará la curva en cuestión. Y, siguiendo un proceso análogo, también será posible obtener el fichero de puntos de una superficie. Para desarrollar esta aplicación, se ha elegido como programa de cálculo simbólico Maple V2, y como programa CAD, AUTOCAD V12.

Ergonomía. Fundamentos para el desarrollo de soluciones ergonómicas

En este texto se presentan algunos conceptos y marcos teóricos útiles para el análisis del trabajo en ergonomía. El objetivo es mostrar los conceptos de base para el estudio del trabajo en la tradición de la ergonomía de la actividad, y analizar de manera general algunos de los modelos empleados para el análisis de una actividad de trabajo. Inicialmente se abordan los principios teóricos de la ergonomía y los principios que provienen de la fisiología, la biomecánica, la psicología y la sociología; también se presentan los acercamientos metodológicos empleados en esta misma perspectiva para el análisis de actividades de trabajo. Se parte del principio de que un estudio ergonómico del trabajo se puede llevar a cabo desde una doble perspectiva: la perspectiva analítica y la perspectiva comprensiva.

In situ (enciclopèdia audiovisual de les ciències i les tècniques) : la màquina terra. 'In situ (enciclopedia audiovisual de las ciencias y las técnicas) : la máquina tierra'.

Este vídeo forma parte de la Enciclopedia Audiovisual de las Ciencias y las Técnicas, y se estructura en capítulos de cuatro minutos. Cada capítulo expone el estudio de un objeto o fenómeno científico y propone: recordatorios, definiciones, exploraciones para entender mejor un funcionamiento, animaciones para representar fenómenos complejos, descubrimientos y aplicaciones y puntos que remiten a otros capítulos de la enciclopedia directamente relacionados con el tema que se trata. Los capítulos incluidos en este volumen son: satélites y geología; el mapa geológico; la brújula; el microscopio petrográfico; la perforación; la erosión terrestre; los sedimientos y las rocas; los recursos del subsuelo; los volcanes; los terremotos; el sismógrafo; la tomografía sísmica; el metamorfismo; la tectónica de placas; la actividad interna del planeta y, los riesgos naturales.

Activitats de matemàtiques del grup Interface. 'Actividades de matemáticas del grupo Interface'.

Nueve paquetes de actividades para Windows para ciclo superior de Primaria. Se trabajan medidas de capacidad y longitud y masa, fracciones, enteros y porcentajes entre otros contenidos. Las actividades se basan en ejercicios visuales y problemas. Permite instalar el programa o hacer una copia en un disquete.