(Table T2) Stable carbon and oxygen isotopes of DSDP Leg 30, Leg 33, ODP Leg 130 and Leg 192 sites, Ontong Java Plateau

Stable isotopic analyses of bulk carbonates recovered from Ontong Java Plateau during Ocean Drilling Program (ODP) Leg 192 (Holes 1183A and 1186A) show an ~0.5 per mil increase in d18O values from the upper Campanian/lower Maastrichtian to the upper Maastrichtian. This shift is consistent with widespread evidence for cooling at this time. Similar shifts were found at other localities on Ontong Java Plateau (Deep Sea Drilling Project [DSDP] Sites 288 and 289 and ODP Site 807) and at DSDP Site 317 on Manihiki Plateau. These data extend evidence for Maastrichtian cooling into the southwestern tropical and subtropical Pacific. The record of apparent cooling survives despite a significant diagenetic overprint at all sites. Comparing average Maastrichtian d18O values among sites suggests that diagenesis caused d18O to first be shifted toward higher values and then back toward lower values as burial depth increased. Carbon isotopes at the six sites show no apparent primary shifts, but at four sites, the Cretaceous/Tertiary boundary interval coincides with a negative excursion attributed to alteration of sediments near the boundary.

How did the crisis affect small and medium-sized enterprises? -- from a field study of the metal-working industry in Java

This paper focuses on the impact of Indonesia's economic crisis on small and medium-sized enterprises (SMEs). It shows how the performance of SMEs during the crisis varied widely even in the same industrial subsector, and found that the factors most affecting performance have been market orientation and the linkages that the SMEs have formed with the buyers of their products. Well-performing SMEs were found to have utilized putting-out linkages with wholesalers which enabled them to switch to products having better markets. On the other hand, the SMEs which had subcontracting linkages with assemblers or contracting linkages with user-factories (with the exception of SMEs having export-oriented linkages) suffered badly in the crisis because of specificity of products with little room for switching. The paper also found that exposure to debt due to borrowing for investment has been another factor affecting performance, but that enterprise size has had no linear correlation with performance.

Communication Middleware for Distributed Hard Real-Time Systems in Java

Distributed real-time embedded systems are becoming increasingly important to society. More demands will be made on them and greater reliance will be placed on the delivery of their services. A relevant subset of them is high-integrity or hard real-time systems, where failure can cause loss of life, environmental harm, or signi���cant ���nancial loss. Additionally, the evolution of communication networks and paradigms as well as the necessity of demanding processing power and fault tolerance, motivated the interconnection between electronic devices; many of the communications have the possibility of transferring data at a high speed. The concept of distributed systems emerged as systems where different parts are executed on several nodes that interact with each other via a communication network. Java���s popularity, facilities and platform independence have made it an interesting language for the real-time and embedded community. This was the motivation for the development of RTSJ (Real-Time Speci���cation for Java), which is a language extension intended to allow the development of real-time systems. The use of Java in the development of high-integrity systems requires strict development and testing techniques. However, RTJS includes a number of language features that are forbidden in such systems. In the context of the HIJA project, the HRTJ (Hard Real-Time Java) pro���le was developed to de���ne a robust subset of the language that is amenable to static analysis for high-integrity system certi���cation. Currently, a speci���cation under the Java community process (JSR- 302) is being developed. Its purpose is to de���ne those capabilities needed to create safety critical applications with Java technology called Safety Critical Java (SCJ). However, neither RTSJ nor its pro���les provide facilities to develop distributed realtime applications. This is an important issue, as most of the current and future systems will be distributed. The Distributed RTSJ (DRTSJ) Expert Group was created under the Java community process (JSR-50) in order to de���ne appropriate abstractions to overcome this problem. Currently there is no formal speci���cation. The aim of this thesis is to develop a communication middleware that is suitable for the development of distributed hard real-time systems in Java, based on the integration between the RMI (Remote Method Invocation) model and the HRTJ pro���le. It has been designed and implemented keeping in mind the main requirements such as the predictability and reliability in the timing behavior and the resource usage. iThe design starts with the de���nition of a computational model which identi���es among other things: the communication model, most appropriate underlying network protocols, the analysis model, and a subset of Java for hard real-time systems. In the design, the remote references are the basic means for building distributed applications which are associated with all non-functional parameters and resources needed to implement synchronous or asynchronous remote invocations with real-time attributes. The proposed middleware separates the resource allocation from the execution itself by de���ning two phases and a speci���c threading mechanism that guarantees a suitable timing behavior. It also includes mechanisms to monitor the functional and the timing behavior. It provides independence from network protocol de���ning a network interface and modules. The JRMP protocol was modi���ed to include two phases, non-functional parameters, and message size optimizations. Although serialization is one of the fundamental operations to ensure proper data transmission, current implementations are not suitable for hard real-time systems and there are no alternatives. This thesis proposes a predictable serialization that introduces a new compiler to generate optimized code according to the computational model. The proposed solution has the advantage of allowing us to schedule the communications and to adjust the memory usage at compilation time. In order to validate the design and the implementation a demanding validation process was carried out with emphasis in the functional behavior, the memory usage, the processor usage (the end-to-end response time and the response time in each functional block) and the network usage (real consumption according to the calculated consumption). The results obtained in an industrial application developed by Thales Avionics (a Flight Management System) and in exhaustive tests show that the design and the prototype are reliable for industrial applications with strict timing requirements. Los sistemas empotrados y distribuidos de tiempo real son cada vez m��s importantes para la sociedad. Su demanda aumenta y cada vez m��s dependemos de los servicios que proporcionan. Los sistemas de alta integridad constituyen un subconjunto de gran importancia. Se caracterizan por que un fallo en su funcionamiento puede causar p��rdida de vidas humanas, da��os en el medio ambiente o cuantiosas p��rdidas econ��micas. La necesidad de satisfacer requisitos temporales estrictos, hace m��s complejo su desarrollo. Mientras que los sistemas empotrados se sigan expandiendo en nuestra sociedad, es necesario garantizar un coste de desarrollo ajustado mediante el uso t��cnicas adecuadas en su dise��o, mantenimiento y certi���caci��n. En concreto, se requiere una tecnolog��a ���exible e independiente del hardware. La evoluci��n de las redes y paradigmas de comunicaci��n, as�� como la necesidad de mayor potencia de c��mputo y de tolerancia a fallos, ha motivado la interconexi��n de dispositivos electr��nicos. Los mecanismos de comunicaci��n permiten la transferencia de datos con alta velocidad de transmisi��n. En este contexto, el concepto de sistema distribuido ha emergido como sistemas donde sus componentes se ejecutan en varios nodos en paralelo y que interact��an entre ellos mediante redes de comunicaciones. Un concepto interesante son los sistemas de tiempo real neutrales respecto a la plataforma de ejecuci��n. Se caracterizan por la falta de conocimiento de esta plataforma durante su dise��o. Esta propiedad es relevante, por que conviene que se ejecuten en la mayor variedad de arquitecturas, tienen una vida media mayor de diez anos y el lugar �� donde se ejecutan puede variar. El lenguaje de programaci��n Java es una buena base para el desarrollo de este tipo de sistemas. Por este motivo se ha creado RTSJ (Real-Time Speci���cation for Java), que es una extensi��n del lenguaje para permitir el desarrollo de sistemas de tiempo real. Sin embargo, RTSJ no proporciona facilidades para el desarrollo de aplicaciones distribuidas de tiempo real. Es una limitaci��n importante dado que la mayor��a de los actuales y futuros sistemas ser��n distribuidos. El grupo DRTSJ (DistributedRTSJ) fue creado bajo el proceso de la comunidad de Java (JSR-50) con el ���n de de���nir las abstracciones que aborden dicha limitaci��n, pero en la actualidad aun no existe una especi���cacion formal. El objetivo de esta tesis es desarrollar un middleware de comunicaciones para el desarrollo de sistemas distribuidos de tiempo real en Java, basado en la integraci��n entre el modelo de RMI (Remote Method Invocation) y el per���l HRTJ. Ha sido dise��ado e implementado teniendo en cuenta los requisitos principales, como la predecibilidad y la con���abilidad del comportamiento temporal y el uso de recursos. El dise��o parte de la de���nici��n de un modelo computacional el cual identi���ca entre otras cosas: el modelo de comunicaciones, los protocolos de red subyacentes m��s adecuados, el modelo de an��lisis, y un subconjunto de Java para sistemas de tiempo real cr��tico. En el dise��o, las referencias remotas son el medio b��sico para construcci��n de aplicaciones distribuidas las cuales son asociadas a todos los par��metros no funcionales y los recursos necesarios para la ejecuci��n de invocaciones remotas s��ncronas o as��ncronas con atributos de tiempo real. El middleware propuesto separa la asignaci��n de recursos de la propia ejecuci��n de���niendo dos fases y un mecanismo de hebras especi���co que garantiza un comportamiento temporal adecuado. Adem��s se ha incluido mecanismos para supervisar el comportamiento funcional y temporal. Se ha buscado independencia del protocolo de red de���niendo una interfaz de red y m��dulos espec�����cos. Tambi��n se ha modi���cado el protocolo JRMP para incluir diferentes fases, par��metros no funcionales y optimizaciones de los tama��os de los mensajes. Aunque la serializaci��n es una de las operaciones fundamentales para asegurar la adecuada transmisi��n de datos, las actuales implementaciones no son adecuadas para sistemas cr��ticos y no hay alternativas. Este trabajo propone una serializaci��n predecible que ha implicado el desarrollo de un nuevo compilador para la generaci��n de c��digo optimizado acorde al modelo computacional. La soluci��n propuesta tiene la ventaja que en tiempo de compilaci��n nos permite plani���car las comunicaciones y ajustar el uso de memoria. Con el objetivo de validar el dise��o e implementaci��n se ha llevado a cabo un exigente proceso de validaci��n con ��nfasis en: el comportamiento funcional, el uso de memoria, el uso del procesador (tiempo de respuesta de extremo a extremo y en cada uno de los bloques funcionales) y el uso de la red (consumo real conforme al estimado). Los buenos resultados obtenidos en una aplicaci��n industrial desarrollada por Thales Avionics (un sistema de gesti��n de vuelo) y en las pruebas exhaustivas han demostrado que el dise��o y el prototipo son ���ables para aplicaciones industriales con estrictos requisitos temporales.

Sistema de Autenticaci��n Universitario Basado en Java Card y Certificado Digital X.509.

Este art��culo presenta una soluci��n al problema de autenticaci��n segura, portable y expandible realizando una combinaci��n de la tecnolog��a Java y el almacenamiento del certificado digital X.509 en las tarjetas Java para acceder a los servicios ofrecidos por una instituci��n, en este caso concreto la Universidad Tecnol��gica de Panam��, garantizando la autenticidad, confidencialidad, integridad y no repudio.

Autenticaci��n Basada en Java Card y en Certificado X.509 para Ambientes Universitarios.

Este paper presenta la tecnolog��a Java Card y los certificados X.509 como m��todo de autenticaci��n en aplicaciones web en ambientes universitarios, en el caso concreto la Universidad Tecnol��gica de Panam�� (UTP). La soluci��n consiste en mejorar el escenario de acceso a los servicios de la UTP tratando de extender el uso de la Infraestructura de Clave P��blica, llevando a cabo la integraci��n de estas tecnolog��as que aporten mayor seguridad a todos los usuarios y que gocen de un acceso a los servicios ofrecidos de manera flexible, segura, garantizando la autenticidad, confidencialidad, integridad y no repudio.

User-definable resource usage bounds analysis for java bytecode

Automatic cost analysis of programs has been traditionally concentrated on a reduced number of resources such as execution steps, time, or memory. However, the increasing relevance of analysis applications such as static debugging and/or certiflcation of user-level properties (including for mobile code) makes it interesting to develop analyses for resource notions that are actually application-dependent. This may include, for example, bytes sent or received by an application, number of files left open, number of SMSs sent or received, number of accesses to a dat��base, money spent, energy consumption, etc. We present a fully automated analysis for inferring upper bounds on the usage that a Java bytecode program makes of a set of application programmer-deflnable resources. In our context, a resource is defined by programmer-provided annotations which state the basic consumption that certain program elements make of that resource. From these deflnitions our analysis derives functions which return an upper bound on the usage that the whole program (and individual blocks) make of that resource for any given set of input data sizes. The analysis proposed is independent of the particular resource. We also present some experimental results from a prototype implementation of the approach covering a signiflcant set of interesting resources.

Safe upper-bounds inference of energy consumption for java bytecode applications

Abstract is not available.