Steganography: a class of secure and robust algorithms

This research work presents a new class of non-blind information hiding algorithms that are stego-secure and robust. They are based on some finite domains iterations having the Devaney's topological chaos property. Thanks to a complete formalization of the approach we prove security against watermark-only attacks of a large class of steganographic algorithms. Finally a complete study of robustness is given in frequency DWT and DCT domains.Comment: Published in The Computer Journal special issue about steganograph

Integrated Approach to Assignment, Scheduling and Routing Problems in a Sales Territory Business Plan

AbstractThis paper considers a real life case study that determines the minimum number of sellers required to attend a set of customers located in a certain region taking into account the weekly schedule plan of the visits, as well as the optimal route. The problem is formulated as a combination of assignment, scheduling and routing problems. In the new formulation, case studies of small size subset of customers of the above type can be solved optimally. However, this subset of customers is not representative within the business plan of the company. To overcome this limitation, the problem is divided into three phases. A greedy algorithm is used in Phase I in order to identify a set of cost-effective feasible clusters of customers assigned to a seller. Phase II and III are then used to solve the problem of a weekly program for visiting the customers as well as to determine the route plan using MILP formulation. Several real life instances of different sizes have been solved demonstrating the efficiency of the proposed approach

E-banking operational risk assessment. A soft computing approach in the context of the Nigerian banking industry.

This study investigates E-banking Operational Risk Assessment (ORA) to enable the development of a new ORA framework and methodology. The general view is that E-banking systems have modified some of the traditional banking risks, particularly Operational Risk (OR) as suggested by the Basel Committee on Banking Supervision in 2003. In addition, recent E-banking financial losses together with risk management principles and standards raise the need for an effective ORA methodology and framework in the context of E-banking. Moreover, evaluation tools and / or methods for ORA are highly subjective, are still in their infant stages, and have not yet reached a consensus. Therefore, it is essential to develop valid and reliable methods for effective ORA and evaluations. The main contribution of this thesis is to apply Fuzzy Inference System (FIS) and Tree Augmented Naïve Bayes (TAN) classifier as standard tools for identifying OR, and measuring OR exposure level. In addition, a new ORA methodology is proposed which consists of four major steps: a risk model, assessment approach, analysis approach and a risk assessment process. Further, a new ORA framework and measurement metrics are proposed with six factors: frequency of triggering event, effectiveness of avoidance barriers, frequency of undesirable operational state, effectiveness of recovery barriers before the risk outcome, approximate cost for Undesirable Operational State (UOS) occurrence, and severity of the risk outcome. The study results were reported based on surveys conducted with Nigerian senior banking officers and banking customers. The study revealed that the framework and assessment tools gave good predictions for risk learning and inference in such systems. Thus, results obtained can be considered promising and useful for both E-banking system adopters and future researchers in this area

A systematic approach for detecting faults in agent designs

This thesis proposes a mechanism, including automated tool support, for early-phase defect detection by comparing the plan structures of a belief-desire-intention (BDI) agent design against the following: (1) requirement models, specified in terms of scenarios and goals; and (2) agent communication models. The intuition of our approach is to extract sets of possible behaviour runs from the agent-behaviour models and to verify whether these runs conform to the specifications of the system-to-be. The proposed approach in this thesis is applicable at design time and does not require source code. Our approach is based on the Prometheus agent-design methodology but is applicable to other methodologies that support the same notions. We evaluate the proposed verification framework on designs, ranging from student projects to case studies of industry-level projects. Our evaluation demonstrates that even a simple specification developed by relatively experienced developers is prone to defects, and our approach is successful in uncovering most of these defects. In addition, we conduct a scalability analysis of our methods, and the outcomes reveal that our approach can scale when designs grow in size

Communicating Climate Change In Internet Discussion Fora: Processes and Implications

Communicating climate change issues in the Internet era requires new strategies that incorporate online communication. The rapid growth of new media and widespread use of the internet has marked everyday lifestyles in modern society. Information on a wide range of social issues, including climate change, is disseminated and debated through online discussions in internet fora. In this research, communication on internet fora and other potential forms of online social interaction are explored, to identify ways to enhance climate change communication on the Internet. The thesis raises three research questions to explore the communication context of internet fora discussion, namely: what are characteristics of the communication process on internet fora? Who is involved in the communication process? What influences do these online communication activities have on users’ everyday activities? The research applies a mixed-methods approach of analysing the usage of Internet fora and the contents of fora communication activities to explore these questions. This includes qualitative reviews of topic-thread discussions to reveal users’ roles in discussions, as well as surveys of fora users. It is argued that with increasing levels of interaction among communicators (people who post or reply to articles in order to express or respond ideas) on internet fora, these communicators are mobilised to join the online discussion process, competing for opinion leadership. The online discussions further contribute to the formation of opinions on climate change, as climate change and related issues are discussed The thesis thereby aims to contribute to the development of effective approaches for opinion formation and climate change communication online, and to encourage individuals to discuss changing behaviour patterns and public engagement of greenhouse gas reduction actions

L'abduction en conception architecturale : une sémiose hypostatique

Cette thèse développe un modèle sémiotique de l’abduction pour représenter un processus de conception architecturale. Elle formalise ce processus par une dualisation hypostatique du rapport sémiotique entre un problème de conception, saisi en tant que signe, et la possibilité de sa matérialisation géométrique. La dualisation réintègre ce signe dans le domaine des systèmes de savoir-concevoir utilisés en conception architecturale, et par conséquent, elle génère de nouvelles solutions architecturales. L’abduction modifie les connaissances préalables engagées dans la production d’une solution (l’hypothèse) et en introduit de nouvelles. La complexité du processus de conception implique, au niveau méthodologique et à partir d’une position épistémologique constructiviste, l’intégration de la subjectivité du concepteur dans le modèle. Ainsi résulte une incertitude des interactions entre problème de conception, production de solution, concepteur et contexte. La sémiotisation de l’abduction architecturale explicite le rôle central de l’interprétation dans la création d’une solution. D’ailleurs, la dualisation s’appuie sur la théorie des possibilités pour opérationnaliser le calcul interprétatif incertain et pour valider les hypothèses générées. En retour, la gestion de la propagation de cette incertitude, dans le modèle sémiotique, facilite l’identification et la formulation des solutions, et rend possible une émergence observationnelle de la nouveauté. Le modèle développé est appliqué à un cas de transformations architecturales géométriques dans un milieu urbain fortement caractérisé.This thesis develops a semiotic model of abduction to represent a process of architectural design. It formalizes this process by the means of a hypostatic dualization, applied to the semiotic relationship between, on the one hand, a design problem, considered as a sign, and on the other, the possibility of its geometric materialization. The dualization reintegrate this sign in the domain of know-how systems used in architectural design, and consequently, it generates new architectural solutions. Abduction modifies and augments the prior knowledge involved in producing the solution (the hypothesis). From a constructivist stance and the ensuing methodological viewpoint, the complexity of the design process implies embedding the designer’s subjectivity in the model. Thus arises an uncertainty about the interactions among design problem, solution production, designer and context. Semiotizing architectural abduction reveals the central role played by interpretation in creating a solution. Besides, dualization relies on possibility theory to formalize the resulting, and uncertain, interpretation calculus, and to validate the obtained hypotheses. In return, managing the uncertainty propagation within the semiotic model, facilitates the identification and the formulation of architectural solutions and allows for an observational emergence of novelty. The developed model is applied to a case of architectural geometric transformations in a heavily characterized neighborhood

Service-oriented IT-Systems for Highly Flexible Business Processes

Der vorliegende Band „Dienstorientierte IT-Systeme für hochflexible Geschäftsprozesse“ enthält ausgewählte Ergebnisse des Forschungsverbundes forFLEX aus den Jahren 2008 - 2011. Ausgehend von einer Charakterisierung des Forschungsfeldes und zwei fallstudienbasierten Anwendungsszenarien werden Fragen der Analyse, der Modellierung und Gestaltung sowie der Infrastruktur, Sicherheit und Werkzeugunterstützung von hochflexiblen Geschäftsprozessen und ihrer Unterstützung durch dienstorientierte IT-Systeme untersucht. Das Buch wendet sich an IT-Fach- und Führungskräfte in Wirtschaft und Verwaltung sowie an Wissenschaftler, die an der Analyse und Gestaltung von Flexibilitätspotenzialen (teil-) automatisierter Geschäftsprozesse interessiert sind