AUTOMATED CODE GENERATION FOR SAFETY-RELATED APPLICATIONS: A CASE STUDY

This paper addresses issues relating to the suitability of using automated code generation(ACG) technologies for the development of real-time, safety-critical systems. This researchexplored the characteristics of model-based software development methodologies and the automatedcode generation tools that support them. Specifically, data related to the engineeringchallenges, skills, and effort associated with ACG practices and technologies were collectedas part of a case study. Characteristics such as the generated code’s organization, size, readability,traceability to model, real-time constructs, and exception handling were identified. Inaddition, the case study involved software engineering practices that incorporate integratedanalysis and design iterations throughout a model-based development process. The researchinvestigated both the static and dynamic characteristics of the selected techniques and tools,identified characteristics of ACG tools with potential impact on safety, and considered thesemantic consistency between representations

Expansion dynamics of Lennard-Jones systems

The dynamics of the expansion of a Lennard-Jones system, initially confined at high density and subsequently expanding freely in the vacuum, is confronted to an expanding statistical ensemble, derived in the diluted quasi-ideal Boltzmann approximation. The description proves to be fairly accurate at predicting average one-body global observables, but important deviations are observed in the configuration-space structure of the events. Possible implications for finite expanding physical systems are outlined

Diagnostik und Therapie der Divertikulitis:modifizierte Stadieneinteilung der Divertikelkrankheit und Divertikulitisscore

Beruhend auf der retrospektiven Datenanalyse des Patientenkollektivs der Kreisklinik Tuttlingen wurde in der vorliegenden Arbeit eine modifizierte Stadieneinteilung der Divertikelkrankheit erarbeitet. Zusätzlich wurde ein aus laborchemischen (CRP und die Leukozytenzahl) und klinischen Parametern bestehender Score entwickelt, der eine klinische Unterscheidung zwischen einer leichten und einer moderaten bis schweren (Phlegmone bis freie Perforation) Divertikulitis ermöglicht. Die in der vorliegenden Studie erarbeitete Stadieneinteilung der Divertikelkrankheit besteht neben dem Stadium 0 (asymptomatische Divertikulose) und dem Stadium 1 (symptomatische Divertikulose und divertikuläre Kolitis) aus verschiedenen Komponenten: den Hauptkomplikationen (Stadium 2 bis 5), den Sekundärkomplikationen einer Divertikulitis und den prognostischen Risikofaktoren. <br

Kinetic-energy release in Coulomb explosion of metastable C3H52+

C3H52+, formed by electron impact ionization of propane, undergoes metastable decay into C2H2++CH3+. We have monitored this reaction in a magnetic mass spectrometer of reversed geometry that is equipped with two electric sectors (BEE geometry). Three different techniques were applied to identify the fragment ions and determine the kinetic-energy release (KER) of spontaneous Coulomb explosion of C3H52+ in the second and third field free regions of the mass spectrometer. The KER distribution is very narrow, with a width of about 3% [root-mean square standard deviation]. An average KER of 4.58+/-0.15 eV is derived from the distribution. High level ab initio quantum-chemical calculations of the structure and energetics of C3H52+ are reported. The activation barrier of the reverse reaction, CH3++C2H2+ (vinylidene), is computed. The value closely agrees with the experimental average KER, thus indicating that essentially all energy available in the reaction is partitioned into kinetic energy. (C) 2003 American Institute of Physics

Mechanisms and dynamics of the metastable decay in Ar-2(+)

A detailed experimental as well as theoretical investigation of the properties of the metastable dissociation Ar-2(+)--\u3eAr++Ar is presented. The mass-analyzed ion kinetic energy (MIKE) scan technique has been performed using a three sector field mass spectrometer. The possible mechanisms of the metastability of Ar-2(+) have been examined and the observed decay process is assigned to the II(1/2)(u)--\u3eI(1/2)(g) bound to continuum radiative transition, in agreement with earlier work. The calculation of the theoretical shape of the kinetic energy release distribution of fragment ions allowed us to construct the theoretical MIKE peak and compare it with the raw experimental data. The accuracy of various sets of potential energy curves for Ar-2(+) is discussed, as well as the way of production of the metastable Ar-2(+)[II(1/2)(u)] electronic state by electron impact. Excellent agreement between the experimental data and theoretical model has been observed. (C) 2004 American Institute of Physics

Multi-scale X-ray Tomography of Solder Interconnects in Microelectronics

Advanced packaging, including 3D IC integration, is one of the main drivers in packaging and system integration to meet the requirements for miniaturized smart systems with high functionality and high performance. For 3D stacking of wafers or dies, interconnections like micro solder bumps and Cu pillars are used. Figure 1 (left) shows a stack with a TSV interposer structure [1]. 3D-stacked products and advanced packaging challenge materials and process characterization. The control of the micro-bump quality is a particular issue. Special tasks are the characterization of the geometry of the solder bumps to estimate the stress enhancement risks, the nondestructive imaging of micron-size pores and of intermetallic phases as well as the visualization of cracks. Several NDE techniques for metrology and failure analysis are currently under discussion. In this paper, the potential and the limits of micro XCT and nano XCT for NDE of solder interconnects are described. Strategies for nondestructive evaluation of geometry, materials and defects are discussed. It is shown that multi-scale imaging with several resolution ranges is one potential approach. Micro XCT (resolution about 1 m) and nano XCT (resolution about 50 nm) are very useful lab-based techniques with a promising prospect for the future. We demonstrate the capabilities for nondestructive imaging of multi-die stacks with TSVs and micro solder bumps. Figure 1 (middle and right) right demonstrates a micro XCT overview and a nano XCT ROI study of such a multi-die stack with solder interconnects. An analysis of individual solder bumps reveals mismatches in relative positioning, variability in the shape, micron-size pores, and the distribution of intermetallic phases. This information is important to evaluate the respective process steps (process control) and the product reliability (quality control). Since deviations from the targeted geometry and defects are difficult to locate precisely from a two-dimensional image, X-ray computed tomography has to be applied

Automated Code Generation For Safety-Related Applications: A Case Study

This paper addresses issues relating to the suitability of using automated code generation(ACG) technologies for the development of real-time, safety-critical systems. This researchexplored the characteristics of model-based software development methodologies and the automatedcode generation tools that support them. Specifically, data related to the engineeringchallenges, skills, and effort associated with ACG practices and technologies were collectedas part of a case study. Characteristics such as the generated code’s organization, size, readability,traceability to model, real-time constructs, and exception handling were identified. Inaddition, the case study involved software engineering practices that incorporate integratedanalysis and design iterations throughout a model-based development process. The researchinvestigated both the static and dynamic characteristics of the selected techniques and tools,identified characteristics of ACG tools with potential impact on safety, and considered thesemantic consistency between representations

Numerical simulation of the thermal fragmentation process in fullerene C60

The processes of defect formation and annealing in fullerene C60 at T=(4000-6000)K are studied by the molecular dynamics technique with a tight-binding potential. The cluster lifetime until fragmentation due to the loss of a C2 dimer has been calculated as a function of temperature. The activation energy and the frequency factor in the Arrhenius equation for the fragmentation rate have been found to be Ea = (9.2 +- 0.4) eV and A = (8 +- 1)10^{19} 1/s. It is shown that fragmentation can occur after the C60 cluster loses its spherical shape. This fact must be taken into account in theoretical calculations of Ea.Comment: 12 pages, 3 figure

Redesign and initial validation of an instrument to assess the motivational qualities of music in exercise: The Brunel Music Rating Inventory-2

In the present study, a measure to assess the motivational qualities of music in exercise was redesigned, extending previous research efforts (Karageorghis et al., 1999). The original measure, the Brunel Music Rating Inventory (BMRI), had shown limitations in its factor structure and its applicability to non-experts in music selection. Redesign of the BMRI used in-depth interviews with eight participants (mean age 31.9 years, s¼8.9 years) to establish the initial item pool, which was examined using a series of confirmatory factor analyses. A single-factor model provided a good fit across three musical selections with different motivational qualities (comparative fit index, CFI: 0.95 – 0.98; standardized root mean residual, SRMR: 0.03 – 0.05). The single-factor model also demonstrated acceptable fit across two independent samples and both sexes using one piece of music (CFI: 0.86 – 1.00; SRMR: 0.04 – 0.07). The BMRI was designed for experts in selecting music for exercise (e.g. dance aerobic instructors), whereas the BMRI-2 can be used both by exercise instructors and participants. The psychometric properties of the BMRI-2 are stronger than those of the BMRI and it is easier to use. The BMRI-2 provides a valid and internally consistent tool by which music can be selected to accompany a bout of exercise or a training session. Furthermore, the BMRI-2 enables researchers to standardize music in experimental protocols involving exercise-related tasks