Advanced manned space flight simulation and training: An investigation of simulation host computer system concepts

The findings of a preliminary investigation by Southwest Research Institute (SwRI) in simulation host computer concepts is presented. It is designed to aid NASA in evaluating simulation technologies for use in spaceflight training. The focus of the investigation is on the next generation of space simulation systems that will be utilized in training personnel for Space Station Freedom operations. SwRI concludes that NASA should pursue a distributed simulation host computer system architecture for the Space Station Training Facility (SSTF) rather than a centralized mainframe based arrangement. A distributed system offers many advantages and is seen by SwRI as the only architecture that will allow NASA to achieve established functional goals and operational objectives over the life of the Space Station Freedom program. Several distributed, parallel computing systems are available today that offer real-time capabilities for time critical, man-in-the-loop simulation. These systems are flexible in terms of connectivity and configurability, and are easily scaled to meet increasing demands for more computing power

Master/worker parallel discrete event simulation

The execution of parallel discrete event simulation across metacomputing infrastructures is examined. A master/worker architecture for parallel discrete event simulation is proposed providing robust executions under a dynamic set of services with system-level support for fault tolerance, semi-automated client-directed load balancing, portability across heterogeneous machines, and the ability to run codes on idle or time-sharing clients without significant interaction by users. Research questions and challenges associated with issues and limitations with the work distribution paradigm, targeted computational domain, performance metrics, and the intended class of applications to be used in this context are analyzed and discussed. A portable web services approach to master/worker parallel discrete event simulation is proposed and evaluated with subsequent optimizations to increase the efficiency of large-scale simulation execution through distributed master service design and intrinsic overhead reduction. New techniques for addressing challenges associated with optimistic parallel discrete event simulation across metacomputing such as rollbacks and message unsending with an inherently different computation paradigm utilizing master services and time windows are proposed and examined. Results indicate that a master/worker approach utilizing loosely coupled resources is a viable means for high throughput parallel discrete event simulation by enhancing existing computational capacity or providing alternate execution capability for less time-critical codes.Ph.D.Committee Chair: Fujimoto, Richard; Committee Member: Bader, David; Committee Member: Perumalla, Kalyan; Committee Member: Riley, George; Committee Member: Vuduc, Richar

Integration of tools for the Design and Assessment of High-Performance, Highly Reliable Computing Systems (DAHPHRS), phase 1

Systems for Space Defense Initiative (SDI) space applications typically require both high performance and very high reliability. These requirements present the systems engineer evaluating such systems with the extremely difficult problem of conducting performance and reliability trade-offs over large design spaces. A controlled development process supported by appropriate automated tools must be used to assure that the system will meet design objectives. This report describes an investigation of methods, tools, and techniques necessary to support performance and reliability modeling for SDI systems development. Models of the JPL Hypercubes, the Encore Multimax, and the C.S. Draper Lab Fault-Tolerant Parallel Processor (FTPP) parallel-computing architectures using candidate SDI weapons-to-target assignment algorithms as workloads were built and analyzed as a means of identifying the necessary system models, how the models interact, and what experiments and analyses should be performed. As a result of this effort, weaknesses in the existing methods and tools were revealed and capabilities that will be required for both individual tools and an integrated toolset were identified

Handling large data sets for high-performance embedded applications in heterogeneous systems-on-chip

Local memory is a key factor for the performance of accelerators in SoCs. Despite technology scaling, the gap between on-chip storage and memory footprint of embedded applications keeps widening. We present a solution to preserve the speedup of accelerators when scaling from small to large data sets. Combining specialized DMA and address translation with a software layer in Linux, our design is transparent to user applications and broadly applicable to any class of SoCs hosting high-throughput accelerators. We demonstrate the robustness of our design across many heterogeneous workload scenarios and memory allocation policies with FPGA-based SoC prototypes featuring twelve concurrent accelerators accessing up to 768MB out of 1GB-addressable DRAM

Space Station Freedom data management system growth and evolution report

The Information Sciences Division at the NASA Ames Research Center has completed a 6-month study of portions of the Space Station Freedom Data Management System (DMS). This study looked at the present capabilities and future growth potential of the DMS, and the results are documented in this report. Issues have been raised that were discussed with the appropriate Johnson Space Center (JSC) management and Work Package-2 contractor organizations. Areas requiring additional study have been identified and suggestions for long-term upgrades have been proposed. This activity has allowed the Ames personnel to develop a rapport with the JSC civil service and contractor teams that does permit an independent check and balance technique for the DMS

System design for periodic data production management

This research project introduces a new type of information system, the periodic data production management system, and proposes several innovative system design concepts for this application area. Periodic data production systems are common in the information industry for the production of information. These systems process large quantities of data in order to produce statistical reports in predefined intervals. The workflow of such a system is typically distributed world-wide and consists of several semi-computerized production steps which transform data packages. For example, market research companies apply these systems in order to sell marketing information over specified timelines. production of information. These systems process large quantities of data in order to produce statistical reports in predefined intervals. The workflow of such a system is typically distributed world-wide and consists of several semi-computerized production steps which transform data packages. For example, market research companies apply these systems in order to sell marketing information over specified timelines. There has been identified a lack of concepts for IT-aided management in this area. This thesis clearly defines the complex requirements of periodic data production management systems. It is shown that these systems can be defines as IT-support for planning, monitoring and controlling periodic data production processes. Their significant advantages are that information industry will be enabled to increase production performance, and to ease (and speed up) the identification of the production progress as well as the achievable optimisation potential in order to control rationalisation goals. In addition, this thesis provides solutions for he generic problem how to introduce such a management system on top of an unchangeable periodic data production system. Two promising system designs for periodic data production management are derived, analysed and compared in order to gain knowledge about appropriate concepts and this application area. Production planning systems are the metaphor models used for the so-called closely coupled approach. The metaphor model for the loosely coupled approach is project management. The latter approach is prototyped as an application in the market research industry and used as case study. Evaluation results are real-world experiences which demonstrate the extraordinary efficiency of systems based on the loosely coupled approach. Special is a scenario-based evaluation that accurately demonstrates the many improvements achievable with this approach. Main results are that production planning and process quality can vitally be improved. Finally, among other propositions, it is suggested to concentrate future work on the development of product lines for periodic data production management systems in order to increase their reuse

Service-Oriented Process Models in Telecommunication Business

The thesis concentrates on to evaluate challenges in the business process management and the need for Service-oriented process models in telecommunication business to alleviate the integration work efforts and to reduce total costs of ownership. The business aspect concentrates on operations and business support systems which are tailored for communication service providers. Business processes should be designed in conformance with TeleManagement Forum's integrated business architecture framework. The thesis rationalizes the need to transform organizations and their way of working from vertical silos to horizontal layers and to understand transformational efforts which are needed to adopt a new strategy. Furthermore, the thesis introduces service characterizations and goes deeper into technical requirements that a service compliant middleware system needs to support. At the end of the thesis Nokia Siemens Networks proprietary approach – Process Automation Enabling Suite is introduced, and finally the thesis performs two case studies. The first one is Nokia Siemens Networks proprietary survey which highlights the importance of customer experience management and the second one is an overall research study whose results have been derived from other public surveys covering application integration efforts

Parallel and distributed computing techniques in biomedical engineering

Master'sMASTER OF ENGINEERIN

Testes End to End em Microserviços

The microservices architecture is a recent trend in the software engineering community, with the number of research articles in the field increasing, and more companies adopting the architectural style every year. However, the testing aspect of this architecture can sometimes be overlooked, with a lack of guidelines for its execution. Also, microservices testing introduce a lot of different challenges that are not faced when following a monolithic architecture. This work aims to fill some gaps in current microservices testing research by providing a study of five existing service virtualization tools, implementing them in a company system and extracting the results of the tool properties identified through a survey delivered to a convenience sample of software development experts. Finally, the mentioned experts in the microservices field validated the results of the research and the tool identified as the best and provided insights regarding the value of this work.A arquitetura de micros serviços é uma tendência recente na comunidade de engenharia de software, com o número de artigos na área a aumentar e mais empresas a adotar o estilo arquitetónico a cada ano. No entanto, a área dos testes end-to-end desta arquitetura pode às vezes ser esquecido. Além disso, os testes de micros serviços apresentam muitos desafios diferentes que não são enfrentados ao seguir uma arquitetura monolítica. Este trabalho visa preencher algumas lacunas na pesquisa de teste de micros serviços atuais, fornecendo um estudo de cinco ferramentas de virtualização de serviço existentes, implementando-as num sistema empresarial e extraindo os resultados das propriedades da ferramenta identificadas por meio de um questionário entregue a uma amostra de conveniência de especialistas em desenvolvimento de software. Por fim, os citados especialistas na área de micros serviços validaram os resultados da pesquisa e a ferramenta identificada como a melhor e forneceram a sua visão geral sobre o valor deste trabalho