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Many safety-critical computer systems are required to monitor and control physical processes. The four-variable model, which has been used successfully in industry for almost four decades, helps to clarify the behaviors of, and the boundaries between the physical processes, input/output devices, and software. In this model, the acceptable behaviors of the software are constrained by the physical environment, system requirements, and input/output devices. If acceptable software behaviors are possible, then the system requirements are said to be implementable with respect to these constraints. The only acceptability condition proposed in the literature deems as acceptable software behaviors that can lead to undesirable system behaviors, in particular, nondeterministic system behaviors that for the same input sometimes do not produce any results and some other times produce expected results. In this sense, the acceptability condition can be seen as angelic. In this paper we strengthen the acceptability condition using the demonic calculus of relations such that no undesirable system or software behaviors are allowed and prove a necessary and sufficient implementability condition for the system requirements. As a byproduct, we also obtain a mathematical characterization of the least restrictive software specification, which, for all intents and purposes, can play the role of the software requirements. [ABSTRACT FROM AUTHOR]

Abstract: Software product lines are increasingly built using components from specialized suppliers. A company that is in the middle of a supply chain has to integrate components from its suppliers and offer (partially configured) products to its customers. To satisfy both the variability required by each customer and the variability required to satisfy different customers’ needs, it may be necessary for such a company to use components from different suppliers, partly offering the same feature set. This leads to a product line with alternative components, possibly using different mechanisms for interfacing, binding and variability, which commonly occurs in embedded software development. In this paper, we describe the limitations of the current practice of combining heterogeneous components in a product line and describe the challenges that arise from software supply chains. We introduce a model-driven approach for automating the integration between components that can generate a partially or fully configured variant, including glue between mismatched components. We analyze the consequences of using this approach in an industrial context, using a case study derived from an existing supply chain and describe the process and roles associated with this approach. [Copyright &y& Elsevier]

Abstract: We present a new software implementation to more efficiently compute the mutual information for all pairs of genes from gene expression microarrays. Computation of the mutual information is a necessary first step in various information theoretic approaches for reconstructing gene regulatory networks from microarray data. When the mutual information is estimated by kernel methods, computing the pairwise mutual information is quite time-consuming. Our implementation significantly reduces the computation time. For an example data set of 336 samples consisting of normal and malignant B-cells, with 9563 genes measured per sample, the current available software for ARACNE requires 142 hours to compute the mutual information for all gene pairs, whereas our algorithm requires 1.6 hours. The increased efficiency of our algorithm improves the feasibility of applying mutual information based approaches for reconstructing large regulatory networks. [Copyright &y& Elsevier]

Abstract: A novel architecture to accelerate a neocortex inspired cognitive model is presented. The architecture utilizes a collection of context switchable processing elements (PEs). This enables time multiplexing of nodes in the model onto available PEs. A streaming memory system is designed to enable high-throughput computation and efficient use of memory resources. Several scheduling algorithms were examined to efficiently assign network nodes to the PEs. Multiple parallel FPGA-accelerated implementations were evaluated on a Cray XD1. Networks of varying complexity were tested and indicate that hardware acceleration can provide an average throughput gain of 184 times over equivalent parallel software implementations. [Copyright &y& Elsevier]

Abstract: The JYFLTRAP setup has been used for precision mass spectrometry since 2003. An essential part of this setup is the computer-controlled system consisting of software and hardware that is required to operate the instruments. The software has been developed solely at JYFL using LabVIEW and C++ development tools. The hardware consists of devices controlled using Control Area Network (CAN) field bus and Ethernet for communication purposes. LAN/GPIB-gateways, modular multichannel ISEG DC power supplies and WAGO I/O systems are also used. [Copyright &y& Elsevier]

Abstract: Timing has a key role in several traffic control functions encountered in modern packet-switched networks. In order to be effective, a timing unit must provide fine resolution, be simple to implement and scale well with the number of controlled traffic streams. This paper addresses the design, implementation and evaluation of a timing unit that can support accurate and efficient implementations of traffic shaping, policing and charging in packet-switched networks. The timing unit is implemented in hardware and, therefore, overcomes constraints associated with software-based timers. It accommodates a pool of independently-clocked timers and counters, organised in timing blocks, and, consequently, is able to support, in parallel, traffic streams with diverse timing requirements. The design supports shaping and policing through token buckets, leaky buckets and a scheme, variation of the token bucket, that aims at providing statistical quality of service guarantees by exploiting the effective rate concept. Charging is supported by dedicated counters that measure the utilization of the effective rate. The granularity of the timing unit is adjustable in run-time to adapt to changes in the rate parameters of the shaping and policing functions. The validation of the timing unit is done through the development of a prototype board consisting of programmable hardware and embedded software blocks. The temporal resolution of the timing unit and the advantages of the hardware/software co-design are experimentally evaluated. [Copyright &y& Elsevier]

Abstract: High-level performance estimation of embedded software implemented in a particular processor is essential for a fast design space exploration, when the designer needs to evaluate different processor architectures (and their different versions) and also different task allocations in a multiprocessor system. The development of fast and adequate performance estimators is required to achieve the necessary speed in this design phase. However, advanced architectures present many features, such as pipelines, branch prediction mechanisms, and caches, which have a non-linear impact on the execution time, which thus becomes hard to evaluate using simple linear methods. In order to cope with this problem, this paper presents a high-level performance estimator based on a neural network, which easily adapts to the non-linear behaviour of the execution time in advanced architectures and presents a speed-up up to 190 times in comparison with cycle-accurate simulators, using the PowerPC 750 as target architecture. A method for automatic domain classification is proposed to group applications with similar characteristics, resulting in an increase of the estimation precision. For the PowerPC 750, the mean estimation error has been reduced from 7.90% to 6.41% thanks to domain-specific estimators. This precision level and the fast estimation time are suitable for high-level design space exploration, when different architectures or processor versions and different task allocations need to be evaluated in a fast way. [Copyright &y& Elsevier]

Abstract: CommUnity is a formal approach to Software Architecture with a strict separation of the computation, coordination, and distribution aspects. The approach is based on a parallel design language with state, which facilitates the specification of computations compared to the process calculi used by other formal approaches, and on category theory, which provides an intuitive yet precise graph-based semantics for the configuration of components and connectors. The CommUnity Workbench is being developed as a proof of concept of the CommUnity framework, providing a graphical integrated development environment to write components, draw configurations, and execute the resulting system. [Copyright &y& Elsevier]

Abstract: Pooling of magnetoencephalography (MEG) data across laboratories is non-trivial because of differences in hardware, software, and environmental noise levels. To investigate these issues, we conducted a study with the same five subjects at three sites with different MEG arrays: Elekta-Neuromag Vectorview (Boston), VSM MedTech Omega 275 (Albuquerque), and 4D Neuroimaging Magnes 3600 WH (Minneapolis). Subjects were run in a simple somatosensory paradigm. Phantom data were also taken at each site. We developed software to allow comparisons of test/retest reliability across subjects, machines, and analysis methods. Preliminary analyses showed excellent test/retest results within subjects across instruments. Analysis of phantom data showed a localization error of less than 2 mm across multiple software packages. Our results show that (1) instruments from different manufacturers yield similar results for somatosensory data, and that (2) multiple software packages produce very accurate results for simple source configurations. [Copyright &y& Elsevier]

Abstract.: An interactive software system, based on MATLAB computing language and interactive environment, is developed in order to simulate the topographical electric potentials and magnetic field distributions of neuronal activities in the human brain. On basis of the simulated data sets and/or on basis of detected electric potentials and magnetic fields current density reconstructions of the underlying neuronal sources can be carried out with different reconstruction methods and various volume conductor models. For visualization the two- and three-dimensional reconstructed current density distributions can be merged to two- and three-dimensional morphological data sets, i.e. magnetic resonance images or computed tomography images. The system is prepared for clinical use in the field of neurosurgery planning. [Copyright &y& Elsevier]

Abstract: In this paper, we propose the use of Versioned Boxes, which keep a history of values, as the basis for language-level memory transactions. Unlike previous work on software transactional memory, in our proposal read-only transactions never conflict with any other concurrent transaction. This may improve significantly the concurrency on applications which have longer transactions and a high read/write ratio. Furthermore, we discuss how we can reduce transaction conflicts by delaying computations and re-executing only parts of a transaction in case of a conflict. We propose two language-level abstractions to support these strategies: the per-transaction boxes and the restartable transactions. Finally, we lay out the basis for a more generic model, which better supports fine-grained restartable transactions. The goal of this new model is to generalize the previous two abstractions to reduce conflicts. [Copyright &y& Elsevier]

Abstract: MADAMS (Management Architecture for Distributed meAsureMent Services) is a novel service-based software framework designed for publishing, retrieving, configuring, setting up, monitoring and executing distributed measurement services over the Internet. The basic building block is the measurement service, i.e. a software object properly configured and made remote accessible across a network. A measurement service corresponds either to a single (virtual or physical) instrument, or to a collection of measurement services abstracting a test method. Service attributes include the graphical interface which supports user interactions. MADAMS is especially tuned to: (i) defining a common way to manage and use distributed measurement services, (ii) introducing a data-exchange layer for inter-instrument communications, (iii) exploiting a design pattern which separates definition of service functionalities from distribution concerns. This paper introduces MADAMS, outlines its current implementation which depends on Java/Jini, and shows its application to a demand monitoring–control measurement system. [Copyright &y& Elsevier]

Abstract: The CMS collaboration is undertaking a big effort to define the analysis model and to develop software tools with the purpose of analysing several millions of simulated and real data events by a large number of people in many geographically distributed sites. From the computing point of view, one of the most complex issues when doing remote analysis is the data discovery and access. Some software tools were developed in order to move data, make them available to the full international community and validate them for the subsequent analysis. The batch analysis processing is performed with workload management tools developed on purpose, which are mainly responsible for the job preparation and the job submission. The job monitoring and the output management are implemented as the last part of the analysis chain. Grid tools provided by the LCG project are evaluated to gain access to the data and the resources by providing a user friendly interface to the physicists submitting the analysis jobs. An overview of the current implementation and of the interactions between the previous components of the CMS analysis system is presented in this work. [Copyright &y& Elsevier]

Abstract: A novel idea of utilizing only a computer to determine leaf area and perimeter was developed. The procedure is essentially computer software developed in Visual Basic that uses the computer monitor as the working surface to trace leaf outline and determines leaf area, perimeter, length, and width. Testing the software for effects of orientation, shape, and size of objects was carried out using opaque (paper) and transparent (polyvinyl chloride sheet) geometrical planar objects of known properties, such as regular polygons (three to eight sides), rectangles, and circles, developed by AutoCAD precision drawings. Direct leaf samples of mango, guava, egg plant, and castor representing varied shapes and sizes were used in measurements and results were also compared with existing graphical and digital planimetric methods. Component methods used in determination were area under the curve (AUC) and pixel count (PC), which was further divided into pixel count-inside (PCI) and pixel count-total (PCT). In general, geometrical objects area and perimeter measurements were found to be independent of orientation, shape, and size. However, perimeters of squares and rectangles obtained by PC methods were affected by object orientation. As the traced transparent samples do not offer appreciable improvement in estimations, opaque samples are recommended because they are convenient and directly used in measurements. Based on the performance with geometrical objects, the software was considered to handle objects of any shape and size equally well. Measurements with direct leaf samples compared well with the graphical (−4.62% to 7.81% deviation) and digital planimetric (−4.05% to 8.48% deviation) results, and variation was found to exist even among these basic methods possibly due to unavoidable manual tracing errors. Based on this study, PCI method for area and AUC method for perimeter determination are recommended. The developed software proved to be an accurate method for measurements of area and perimeter of leaves and other planar objects, such as maps; extends the application of personal computers to such measurements; and was less expensive as it does not require additional hardware. [Copyright &y& Elsevier]

This paper presents and discusses the results of the project ARVIKA. After a short introduction and presentation of the project goals, the augmented reality system is described. It consists in a Plug-In for internet-browser in which all the software components have been integrated. The advantages and disadvantages of the adopted approaches, as well as the lessons learned from the project are presented in details. Finally, the open issues are discussed and future work to be achieved until a possible implementation of augmented reality in an industrial context is proposed. [Copyright &y& Elsevier]

The new software world is progressing steadily forward but is not yet within range of where it needs to be. This paper presents a mathematical ground for the Lyee methodology, which has already produced several achievements in industry. This method enables us not to attention the sequential order of program execution. By introducing the concept of a state, it is possible to prove the program structure. The construction of such a program structure allows programmers to focus on conditions and formulae that calculate the value. Through this model, a system divided for catching correct requirements quickly is integrated, and its optimal program with minimum repetitions can be generated by rearranging words into the right order. [Copyright &y& Elsevier]

The SDPA (SemidDefinite Programming Algorithm) is known as efficient computer software based on the primal–dual interior-point method for solving SDPs (SemiDefinite Programs). In many applications, however, some SDPs become larger and larger, too large for the SDPA to solve on a single processor. In execution of the SDPA applied to large scale SDPs, the computation of the so-called Schur complement matrix and its Cholesky factorization consume most of the computational time. The SDPARA (SemiDefinite Programming Algorithm paRAllel version) is a parallel version of the SDPA on multiple processors and distributed memory, which replaces these two parts by their parallel implementation using MPI and ScaLAPACK. Through numerical results, we show that the SDPARA on a PC cluster consisting of 64 processors attains high scalability for large scale SDPs without losing the stability of the SDPA. [Copyright &y& Elsevier]