La ense??anza biling??e ingl??s-espa??ol en EE. UU. : un ejemplo de ense??anza dual en Iowa

Memoria de m??ster (Universidad Pablo de Olavide, 2012)

Las relaciones comerciales de América Latina: integraciones económicas regionales y análisis de la proliferación de acuerdos con los EE.UU. (Tema Central)

El objetivo del presente artículo es hacer una reflexión acerca de la nueva geografía comercial de América Latina, relativa a los acuerdos celebrados con los EE.UU. Frente a las incertidumbres en el ámbito regional y multilateral, hoy existe un cierto predominio de un tercer movimiento en las relaciones económicas internacionales, esto es, la proliferación de tratados bilaterales. Aunque estos tratados asuman diferentes contenidos y obligaciones, en general tienen compromisos más rígidos para los países en desarrollo en América Latina, que las obligaciones firmadas en foros de negociación subjetivamente más amplios (como es el caso de la OMC).

Aspectos relevantes del estado actual de las negociaciones del Tratado de Libre Comercio entre Ecuador y EE.UU. (Tema Central)

El artículo, centrándose en el sector agrícola ecuatoriano, hace una descripción del estado en que se encuentran las negociaciones del Tratado de Libre Comercio entre Estados Unidos y Ecuador. De acuerdo con el autor, en el sector agrícola, manejado como tema sensible y relevante por parte de los negociadores ecuatorianos, el ritmo de negociación ha sido desgastante para la parte ecuatoriana debido, entre otras razones, a la inflexibilidad mostrada hasta el momento por parte de los negociadores norteamericanos. Igualmente plantea y analiza dos escenarios factibles una vez concluidas las rondas de negociación: que el Ecuador decida poner un freno al proceso de negociación o que el proceso negociador continúe y las condiciones actuales se flexibilicen, especialmente por parte de los EE.UU. para facilitar la firma del Tratado.

La seguridad nacional de EE. UU. en el nuevo orden global: de la vinculación y expansión a la seguridad patria y el antiterrorismo (Tema Central)

El artículo describe y compara las estrategias de seguridad nacional de Estados Unidos de las administraciones de Bill Clinton y George Bush. Trata de clarificar la forma en que se concibe el espacio nacional estadounidense, mundial y global dentro de estas estrategias.

Relaciones bilaterales entre el Ecuador y EE. UU. durante las décadas de los años ochenta y noventa (Artículos Varios)

Este artículo desarrolla un análisis comparativo de las relaciones bilaterales entre el Ecuador y Estados Unidos, durante los gobiernos de Osvaldo Hurtado, León Febres Cordero, Rodrigo Borja, Sixto Durán Ballén, Abdalá Bucaram, Fabián Alarcón y Jamil Mahuad. El autor encuentra puntos coincidentes y de diferencia en cada una de las administraciones, con respecto a las temáticas prioritarias sobre las que se han desarrollado las relaciones bilaterales: democracia, Derechos Humanos, drogas, deuda externa, comercio y el conflicto bélico Ecuador-Perú.

Efectos en los mercados financieros internacionales de la derogatoria en 1999 de la Ley Glass Steagall de los EE.UU. (Tema Central)

Actualmente la profunda crisis del sistema financiero internacional, similar a la que vivió Estados Unidos en los años treinta, es el punto más importante de discusión en todo el mundo. Por ello, se consideró importante realizar un análisis de la Ley Glass Steagall Act, promulgada en el año 1933, justamente como una salida a la crisis financiera estadounidense, de aquella época, precisando cuáles son sus principales características, y sobre todo los efectos que su derogatoria (en 1999) trajo consigo en el sistema financiero mundial, pues como veremos, para muchos la actual crisis es producto de la inadecuada mezcla de regulación y libertad que se produjo con la promulgación de la Ley Gramm Leach Bliley Act, mediante la cual los bancos comerciales empezaron a incursionar en operaciones bursátiles, actividades que anteriormente estaban vetadas, y por tanto existían garantías suficientes para los depositantes.

MPJ express: Towards thread safe Java HPC

MPJ Express is a thread-safe Java messaging library that provides a full implementation of the mpiJava 1.2 API specification. This specification defines a MPI-like bindings for the Java language. We have implemented two communication devices as part of our library, the first, called niodev is based on the Java New I/O package and the second, called mxdev is based on the Myrinet eXpress library MPJ Express comes with an experimental runtitne, which allows portable bootstrapping of Java Virtual Machines across a cluster or network of computers. In this paper we describe the implementation of MPJ Express. Also, we present a performance comparison against various other C and Java messaging systems. A beta version of MPJ Express was released in September 2005.

Parallel and distributed computing with Java

The Java language first came to public attention in 1995. Within a year, it was being speculated that Java may be a good language for parallel and distributed computing. Its core features, including being objected oriented and platform independence, as well as having built-in network support and threads, has encouraged this view. Today, Java is being used in almost every type of computer-based system, ranging from sensor networks to high performance computing platforms, and from enterprise applications through to complex research-based.simulations. In this paper the key features that make Java a good language for parallel and distributed computing are first discussed. Two Java-based middleware systems, namely MPJ Express, an MPI-like Java messaging system, and Tycho, a wide-area asynchronous messaging framework with an integrated virtual registry are then discussed. The paper concludes by highlighting the advantages of using Java as middleware to support distributed applications.

MPJ express meets gadget: towards a java code for cosmological simulations

Gadget-2 is a massively parallel structure formation code for cosmological simulations. In this paper, we present a Java version of Gadget-2. We evaluated the performance of the Java version by running colliding galaxies simulation and found that it can achieve around 70% of C Gadget-2's performance.

A buffering layer to support derived types and proprietary networks for Java HPC

MPJ Express is our implementation of MPI-like bindings for Java. In this paper we discuss our intermediate buffering layer that makes use of the so-called direct byte buffers introduced in the Java New I/O package. The purpose of this layer is to support the implementation of derived datatypes. MPJ Express is the first Java messaging library that implements this feature using pure Java. In addition, this buffering layer allows efficient implementation of communication devices based on proprietary networks such as Myrinet. In this paper we evaluate the performance of our buffering layer and demonstrate the usefulness of direct byte buffers. Also, we evaluate the performance of MPJ Express against other messaging systems using Myrinet and show that our buffering layer has made it possible to avoid the overheads suffered by other Java systems such as mpiJava that relies on the Java Native Interface.

A buffering layer to support derived types and proprietary networks for Java HPC

MPJ Express is our implementation of MPI-like bindings for Java. In this paper we discuss our intermediate buffering layer that makes use of the so-called direct byte buffers introduced in the Java New I/O package. The purpose of this layer is to support the implementation of derived datatypes. MPJ Express is the first Java messaging library that implements this feature using pure Java. In addition, this buffering layer allows efficient implementation of communication devices based on proprietary networks such as Myrinet. In this paper we evaluate the performance of our buffering layer and demonstrate the usefulness of direct byte buffers. Also, we evaluate the performance of MPJ Express against other messaging systems using Myrinet and show that our buffering layer has made it possible to avoid the overheads suffered by other Java systems such as mpiJava that relies on the Java Native Interface.

Nested parallelism for multi-core HPC systems using Java

Since its introduction in 1993, the Message Passing Interface (MPI) has become a de facto standard for writing High Performance Computing (HPC) applications on clusters and Massively Parallel Processors (MPPs). The recent emergence of multi-core processor systems presents a new challenge for established parallel programming paradigms, including those based on MPI. This paper presents a new Java messaging system called MPJ Express. Using this system, we exploit multiple levels of parallelism - messaging and threading - to improve application performance on multi-core processors. We refer to our approach as nested parallelism. This MPI-like Java library can support nested parallelism by using Java or Java OpenMP (JOMP) threads within an MPJ Express process. Practicality of this approach is assessed by porting to Java a massively parallel structure formation code from Cosmology called Gadget-2. We introduce nested parallelism in the Java version of the simulation code and report good speed-ups. To the best of our knowledge it is the first time this kind of hybrid parallelism is demonstrated in a high performance Java application. (C) 2009 Elsevier Inc. All rights reserved.

A comparative study of Java and C performance in two large-scale parallel applications

In the 1990s the Message Passing Interface Forum defined MPI bindings for Fortran, C, and C++. With the success of MPI these relatively conservative languages have continued to dominate in the parallel computing community. There are compelling arguments in favour of more modern languages like Java. These include portability, better runtime error checking, modularity, and multi-threading. But these arguments have not converted many HPC programmers, perhaps due to the scarcity of full-scale scientific Java codes, and the lack of evidence for performance competitive with C or Fortran. This paper tries to redress this situation by porting two scientific applications to Java. Both of these applications are parallelized using our thread-safe Java messaging system—MPJ Express. The first application is the Gadget-2 code, which is a massively parallel structure formation code for cosmological simulations. The second application uses the finite-domain time-difference method for simulations in the area of computational electromagnetics. We evaluate and compare the performance of the Java and C versions of these two scientific applications, and demonstrate that the Java codes can achieve performance comparable with legacy applications written in conventional HPC languages. Copyright © 2009 John Wiley & Sons, Ltd.

Experimental comparison of the comprehensibility of a Z specification and its implementation in Java

Comprehensibility is often raised as a problem with formal notations, yet formal methods practitioners dispute this. In a survey, one interviewee said 'formal specifications are no more difficult to understand than code'. Measurement of comprehension is necessarily comparative and a useful comparison for a specification is against its implementation. Practitioners have an intuitive feel for the comprehension of code. A quantified comparison will transfer this feeling to formal specifications. We performed an experiment to compare the comprehension of a Z specification with that of its implementation in Java. The results indicate there is little difference in comprehensibility between the two. (C) 2004 Elsevier B.V. All rights reserved.