Electronic Communications of the EASST (European Association of Software Science and Technology)
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Autonomous Units for Solving the Capacitated Vehicle Routing Problem Based on Ant Colony Optimization
Get PDFCommunities of autonomous units and ant colony systems have fundamental features in common. Both consists of a set of autonomously acting units that transform and move around a common environment that is usually a graph. In contrast to ant colony systems, the actions of autonomous units are specified by graph transformation rules which have a precisely defined operational semantics and can be visualized in a straightforward way. In this paper, we model an ant colony system solving the capacitated vehicle routing problem as a community of autonomous units. The presented case study shows that the main characteristics of ant colony systems such as tour construction and pheromone updates
can be captured in a natural way by autonomous units
Middleware for the Internet of Things, Design Goals and Challenges
Get PDFAs the number of wireless devices increases and their size becomes smaller, there can be more interaction between everyday objects of our life. With advances in RFID chips and the introduction of new generations of these devices that are smaller and cheaper, it is possible to put a wireless interface on almost all everyday objects: vehicles, clothes, foodstuffs, etc. This concept is called the \textit{Internet of Things}. Interaction with thousands of wireless devices leads to a continuous and massive flow of events which are generated spontaneously. The question of how to deal with this enormous number of events is challenging and introduces new design goals for a communication mechanism. In this paper we argue that a middleware together with suitable linguistic abstractions is a proper solution. We also point out the challenges in developing this middleware. Moreover, we give an overview of recent related work and describe why they fail to address these challenges
QoS-based Self-Management for Business Processes
Get PDFBusiness processes are commonly implemented as compositions of Web Services, using the Business Process Execution Language (BPEL) as an orchestration specification. Business processes do not only require an appropriate setup but also need to be monitored throughout their runtime, especially when Quality-of-service (QoS) constraints have to be met. Monitoring results may be used for the automated reconfiguration and optimization of business processes. We show how we achieve self-management based on QoS constraints within our system. The BPRules Language that we set up can be used to improve the QoS behavior of business processes by triggering appropriate management actions on the process. Also we propose a service selection strategy for the dynamic selection and replacement of services within business processes
Nutzerintegration in die Anforderungserhebung für Ubiquitous Computing Systeme
Get PDFDer Nutzer wird als die wichtigste Quelle für Anforderungen an technische Systeme gesehen. Die technikgetriebene Entwicklung ubiquitärer Systeme nimmt darauf zurzeit jedoch wenig Rücksicht. Wir beschreiben, wie der Nutzer nach bekannten Requirements Engineering Ansätzen besser in die Anforderungserhebung einbezogen werden kann und welche Probleme dabei auftreten. Dabei stehen die besonderen Eigenschaften ubiquitärerer Systeme – wie die Tatsache, dass der Nutzer das System nicht mehr aktiv bedient, sondern durch Verwendung von Smart Devices steuert – Im Vordergrund. Ein weiterer Fokus bei der von uns beschriebenen Nutzerintegration liegt zudem auf der Tatsache, dass die Nutzer durch die Neuartigkeit ubiquitärer Systeme kaum eine Vorstellung von den sich bietenden Möglichkeiten für ubiquitäre Anwendungen haben und entsprechend anfänglich keine spezifischen Anforderungen nennen können
Security Evaluation and Hardening of Free and Open Source Software (FOSS)
Get PDFRecently, Free and Open Source Software (FOSS) has emerged as an alternative to Commercial-Off- The-Shelf (COTS) software. Now, FOSS is perceived as a viable long-term solution that deserves careful consideration because of its potential for significant cost savings, improved reliability, and numerous advantages over proprietary software. However, the secure integration of FOSS in IT infrastructures is very challenging and demanding. Methodologies and technical policies must be adapted to reliably compose large FOSS-based software systems. A DRDC Valcartier-Concordia University feasibility study completed in March 2004 concluded that the most promising approach for securing FOSS is to combine advanced design patterns and Aspect-Oriented Programming (AOP). Following the recommendations of this study a three years project have been conducted as a collaboration between Concordia University, DRDC Valcartier, and Bell Canada. This paper aims at presenting the main contributions of this project. It consists of a practical framework with the underlying solid semantic foundations for the security evaluation and hardening of FOSS
Using Free/Libre Open Source Software Projects as E-learning Tools
Get PDFFree/Libre Open Source Software (FLOSS) projects can be considered as learning environments in which heterogeneous communities get together to exchange knowledge through discussion and put it into practice through actual contributions to software development, revision and testing. This has encouraged tertiary educators to attempt the inclusion of participation in FLOSS projects as part of the requirements of Software Engineering courses, and pilot studies have been conducted to test the effectiveness of such an attempt. This paper discusses two pilot studies with reference to several studies concerning the role of learning in FLOSS projects and shows how using FLOSS projects as E-learning tools has a potential to increase the quality of the software product
Visualization of Business Process Modeling Anti Patterns
Get PDFPatterns are used to capture and document frequent design activities. Patterns are means to compare the expressiveness of different modeling languages. On the other hand, the term points to undesirable design activities. In the field of business process modeling, useful patterns were collected to help evaluate models and tools. Nevertheless, there was almost no work to capture the unwanted design patterns.
The most common way to model business processes is to use a graphical modeling language. The most widespread notation are business process diagrams modeled in the language BPMN.
In this paper, we formalize structural patterns that can lead to control flow errors in such graphical models. For expressing such error patterns, we use the visual query language BPMN-Q . By using a query processor, a business process modeler is able to identify possible errors in business process diagrams. Moreover, the erroneous parts of the business process diagram can be highlighted when an instance of an error pattern is found. This way, the modeler gets an easy-to-understand feedback in the visual modeling language he or she is familiar with
Verification of Model Transformations
Get PDFWith the increasing use of automatic transformations of models, the correctness of these transformations becomes an increasingly important issue. Especially for model transformation generally defined using abstract description techniques like graph transformations or declarative relational specifications, however, establishing the soundness of those transformations by test-based approaches is not straight-forward. We show how formal verification of soundness conditions over such declarative relational style transformations can be performed using an interactive theorem prover. The relational style allows a direct translation of transformations as well as associated soundness conditions into corresponding axioms and theorems. Using the Isabelle theorem prover, the approach is demonstrated for a refactoring transformation and a connectedness soundness condition
Clang and Coccinelle: Synergising program analysis tools for CERT C Secure Coding Standard certification
Get PDFWriting correct C programs is well-known to be hard, not least due to the many language features intrinsic to C. Writing secure C programs is even harder and, at times, seemingly impossible. To improve on this situation the US CERT has developed and published a set of coding standards, the “CERT C Secure Coding Standard”, that (in the current version) enumerates 118 rules and 182 recommendations with the aim of making C programs (more) secure. The large number of rules and recommendations makes automated tool support essential for certifying that a given system is in compliance with the standard.
In this paper we report on ongoing work on integrating two state of the art analysis tools, Clang and Coccinelle, into a combined tool well suited for analysing and certifying C programs according to, e.g., the CERT C Secure Coding standard or the MISRA (the Motor Industry Software Reliability Assocation) C standard. We further argue that such a tool must be highly adaptable and customisable to each software project as well as to the certification rules required by a given standard.
Clang is the C frontend for the LLVM compiler/virtual machine project which includes a comprehensive set of static analyses and code checkers. Coccinelle is a program transformation tool and bug-finder developed originally for the Linux kernel,
but has been successfully used to find bugs in other Open Source projects such as WINE and OpenSSL
Formal Modeling of Communication Platforms using Reconfigurable Algebraic High-Level Nets
Get PDFCommunication nowadays is based on communication platforms like Skype, Facebook, or SecondLife. The formal modeling and analysis of communication platforms poses considerable challenges, namely highly dynamic structures and complex behavior. Since most of the well-known formal modeling approaches are adequate only for specific aspects of communication platforms, in this paper we introduce the approach of reconfigurable algebraic high-level nets with individual tokens and show in our case study Skype that this approach is adequate for modeling the main aspects and features of communication platforms