1,720,978 research outputs found
Traceability and sysml design slices to support safety inspections: A controlled experiment
No full textCertifying safety-critical software and ensuring its safety requires checking the conformance between safety requirements and design. Increasingly, the development of safety-critical software relies on modeling, and the System Modeling Language (SysML) is now commonly used in many industry sectors. Inspecting safety conformance by comparing design models against safety requirements requires safety inspectors to browse through large models and is consequently time consuming and error-prone. An important concern in relation to traceability is cost effectiveness. Making traceability cost effective requires a careful analysis of the trade-offs between the costs incurred over establishing and maintaining traceability links and the benefits that traceability offers. Traceability is considered worthwhile if it presents a significant advantage for achieving certain goals. In our case, the goals pursued from traceability are to increase the correctness and decrease the effort associated with design safety inspections
A SysML-based approach to traceability management and design slicing in support of safety certification: Framework, tool support, and case studies
No full textContext: Traceability is one of the basic tenets of all safety standards and a key prerequisite for software safety certification. In the current state of practice, there is often a significant traceability gap between safety requirements and software design. Poor traceability, in addition to being a non-compliance issue on its own, makes it difficult to determine whether the design fulfills the safety requirements, mainly because the design aspects related to safety cannot be clearly identified. Objective: The goal of this article is to develop a framework for specifying and automatically extracting design aspects relevant to safety requirements. This goal is realized through the combination of two components: (1) A methodology for establishing traceability between safety requirements and design, and (2) an algorithm that can extract for any given safety requirement a minimized fragment (slice) of the design that is sound, and yet easy to understand and inspect. Method: We ground our framework on System Modeling Language (SysML). The framework includes a traceability information model, a methodology to establish traceability, and mechanisms for model slicing based on the recorded traceability information. The framework is implemented in a tool, named SafeSlice. Results: We prove that our slicing algorithm is sound for temporal safety properties, and argue about the completeness of slices based on our practical experience. We report on the lessons learned from applying our approach to two case studies, one benchmark and one industrial case. Both studies indicate that our approach substantially reduces the amount of information that needs to be inspected for ensuring that a given (behavioral) safety requirement is met by the design. © 2012 Elsevier B.V. All rights reserved
SafeSlice: A model slicing and design safety inspection tool for SysML
Get PDFSoftware safety certification involves checking that the software design meets the (software) safety requirements. In practice, inspections are one of the primary vehicles for ensuring that safety requirements are satisfied by the design. Unless the safety-related aspects of the design are clearly delineated, the inspections conducted by safety assessors would have to consider the entire design, although only small fragments of the design may be related to safety. In a model-driven development context, this means that the assessors have to browse through large models, understand them, and identify the safety-related fragments. This is time-consuming and error-prone, specially noting that the assessors are often third-party regulatory bodies who were not involved in the design. To address this problem, we describe in this paper a prototype tool called, SafeSlice, that enables one to automatically extract the safety-related slices (fragments) of design models. The main enabler for our slicing technique is the traceability between the safety requirements and the design, established by following a structured design methodology that we propose. Our work is grounded on SysML, which is being increasingly used for expressing the design of safety-critical systems. We have validated our work through two case studies and a control experiment which we briefly outline in the paper. © 2011 ACM
Research-based innovation: A tale of three projects in model-driven engineering
No full textIn recent years, we have been exploring ways to foster a closer collaboration between software engineering research and industry both to align our research with practical needs, and to increase awareness about the importance of research for innovation. This paper outlines our experience with three research projects conducted in collaboration with the industry. We examine the way we collaborated with our industry partners and describe the decisions that contributed to the effectiveness of the collaborations. We report on the lessons learned from our experience and illustrate the lessons using examples from the three projects. The lessons focus on the applications of Model-Driven Engineering (MDE), as all the three projects we draw on here were MDE projects. Our goal from structuring and sharing our experience is to contribute to a better understanding of how researchers and practitioners can collaborate more effectively and to gain more value from their collaborations. © 2012 Springer-Verlag
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Co-planning of generation and transmission expansion planning for network resiliency improvement against extreme weather conditions and uncertainty of resiliency sources
No full textGeneration and transmission expansion increase the flexibility of power systems and hence their ability to deal with contingency. This paper presents a resilient-constrained generation and transmission expansion planning (RCGTEP) model considering the occurrence of earthquakes and floods. The proposed model minimizes the investment and operation costs of resiliency sources (RSs) and resiliency (blackout) costs arising from the outage of the network against the occurrence of extreme conditions. For further consideration, uncertainties of load and RSs availability are included as a Stochastic programming model. A hybrid solver of teaching-learning-based optimization (TLBO) and krill herd optimization (KHO) is used to solve the proposed problem and achieve the optimal solution, including a low standard deviation in the final optimal response. The model is tested using a modified version of the IEEE 6-Bus and IEEE 89-Bus transmission networks. Numerical results show the potential of the mentioned approach to improve indices of operation, economics, and resiliency in the transmission network
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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