The distributed ASCI supercomputer project

The Distributed ASCI Supercomputer (DAS) is a homogeneous wide-area distributed system consisting of four cluster computers at different locations. DAS has been used for research on communication software, parallel languages and programming systems, schedulers, parallel applications, and distributed applications. The paper gives a preview of the most interesting research results obtained so far in the DAS project

Acetate Kinase Isozymes Confer Robustness in Acetate Metabolism

Acetate kinase (ACK) (EC no: 2.7.2.1) interconverts acetyl-phosphate and acetate to either catabolize or synthesize acetyl-CoA dependent on the metabolic requirement. Among all ACK entries available in UniProt, we found that around 45% are multiple ACKs in some organisms including more than 300 species but surprisingly, little work has been done to clarify whether this has any significance. In an attempt to gain further insight we have studied the two ACKs (AckA1, AckA2) encoded by two neighboring genes conserved in Lactococcus lactis (L. lactis) by analyzing protein sequences, characterizing transcription structure, determining enzyme characteristics and effect on growth physiology. The results show that the two ACKs are most likely individually transcribed. AckA1 has a much higher turnover number and AckA2 has a much higher affinity for acetate in vitro. Consistently, growth experiments of mutant strains reveal that AckA1 has a higher capacity for acetate production which allows faster growth in an environment with high acetate concentration. Meanwhile, AckA2 is important for fast acetate-dependent growth at low concentration of acetate. The results demonstrate that the two ACKs have complementary physiological roles in L. lactis to maintain a robust acetate metabolism for fast growth at different extracellular acetate concentrations. The existence of ACK isozymes may reflect a common evolutionary strategy in bacteria in an environment with varying concentrations of acetate

Relational architectures and wearable space: Smart schools and the politics of ubiquitous sensation

This paper undertakes an analysis of the “smart school” as a building that both senses and manages bodies through sensory data. The authors argue that smart schools produce a situation of ubiquitous sensation, in which learning environments are continuously sensed, regulated, and controlled through complex sensory ecosystems and data infrastructures. This includes the consideration of ethical and political issues associated with the collection of biometric and environmental data in schools, and the implications for the design and operation of learning environments which are increasingly regulated through decentralised sensor networks. Working through a relational and adaptive theory of architecture, the authors explore ways of intervening in smart schools through the reconceptualization of sensor technologies as “atmospheric media” that operate within a distributed ecology of sensation that exceeds the limited bandwidth of the human senses. Drawing on recent projects in contemporary art, architecture, and interaction design, the authors discuss specific architectural interventions that foreground the atmospheric qualities and ethical problematics of sensor technologies in school buildings

Walking with Media: Towards a mixed reality pedagogy in university learning environments

Recently the fields of architecture, media studies, and education have begun to converge through the proliferation of mixed reality technologies and interfaces. This convergence is widely described as offering new opportunities for immersive, seamless, decentralised and environmentally distributed learning experiences. This chapter contributes to a growing body of research exploring the transformation of learning environments through distributed media networks, digital databases, and innovative pedagogical interventions. It develops a theoretical framework for researching the interconnections between the built environment, mixed reality technologies, and place-based learning experiences and pedagogies. The second part of the chapter focuses on the development of the CubeWalk network, which involved a series of site-specific architectural installations, digital interfaces, and pedagogical interventions on a university campus in NSW, Australia. Two case studies are presented which describe the co-design and evaluation of mixed reality tutorial walks across the university campus. Drawing together insights rendered through the case studies, the chapter offers a series of theoretical propositions for a ‘mixed reality pedagogy’ that is distributed across 21st century learning environments and media networks

UvA-DARE (Digital Academic Repository) Discrete Event Modelling Methodology for Intelligent Transport Systems DISCRETE EVENT MODELLING METHODOLOGY FOR INTELLIGENT TRANSPORT SYSTEMS

SUMMARY Motivated by work on Electronic Fee Collection, we formulate a general simulation concept to evaluate the performance of Intelligent Transport Systems, and introduce the virtual sensor concept as a concept for sensor system modelling. We demand that interaction between elements of the system is well defined, and that their state changes at pre-definable time intervals. As a result we can model the total system as a discrete event model

WEB CACHE REPLACEMENT AND COHERENCE STRATEGIES APPLICATIONS Concurrent Evaluation of Web Cache Replacement and Coherence Strategies

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Multi-microcomputer system for Monte-Carlo calculations

The authors propose a microcomputer system that allows parallel processing for Monte Carlo calculations in lattice gauge theories, simulations of high energy physics experiments and many other fields of current interest. The master-n-slave multiprocessor system is based on the Motorola MC 6800 microprocessor. One attraction of this processor is that it allows up to 16 M Byte random access memory