A framework for the detection and resolution of aspect interactions

Aspect-Oriented Programming (AOP) promises separation of concerns at the implementation level. However, aspects are not always orthogonal and aspect interaction is an important problem. Currently there is almost no support for the detection and resolution of such interactions. The programmer is responsible for identifying interactions between conflicting aspects and implementing conflict resolution code. In this paper, we propose a solution to this problem based on a generic framework for AOP. The contributions are threefold: we present a formal and expressive crosscut language, two static conflict analyses and some linguistic support for conflict resolution

Detection and resolution of aspect interactions

Aspect-Oriented Programming (AOP) promises separation of concerns at the implementation level. However, aspects are not always orthogonal and aspect interaction is an important problem. Currently there is almost no support for the detection and resolution of such interactions. The programmer is responsible for identifying interactions between conflicting aspects and implementing conflict resolution code. In this paper, we propose a solution to this problem based on a generic framework for AOP. The contributions are threefold: we present a formal and expressive crosscut language, two static conflict analyses and some linguistic support for conflict resolution

Composition, reuse and interaction analysis of stateful aspects

Aspect-Oriented Programming promises separation of concerns at the implementation level. However, aspects are not always orrthogonal and aspect interaction is a fundamental problem. In this paper, we extend previous work on a generic framework for the formal definition and interaction analysis of stateful aspects. We propose three important extensions which enhance expressivity while preserving static analyzability of interactions. First, we provide support for variables in aspects in order to share information between different execution points. This allows the definition of more precise aspects and to avoid detection of spurious conflicts. Second, we introduce generic composition operators for aspects. This enables us to provide expressive support for the resolution of conflicts among interacting aspects. Finally, we offer a means to define applicability conditions for aspects. This makes interaction analysis more precise and paves the way for reuse of aspects by making explicit requirements on contexts in which aspects must be used

Sensitivity to the Standard Model Higgs Boson in Exclusive Double Diffraction

We use a Monte Carlo implementation of recently developed models of double diffraction to assess the sensitivity of the LHC experiments to Standard Model Higgs bosons produced in exclusive double diffraction. The signal is difficult to extract, due to experimental limitations related to the first level trigger, and to contamination by inclusive double diffractive background. Assuming the above difficulties can be overcome, the expected signal-to-background ratio is presented as a function of the experimental resolution on the missing mass. Injecting a missing mass resolution of 2 GeV, a signal-to-background ratio of about 0.5 is obtained; a resolution of 1 GeV brings a signal to background ratio of 1. This result is lower than previous estimates, and the discrepancy is explained.Comment: Revised versio

A goal-oriented requirements modelling language for enterprise architecture

Methods for enterprise architecture, such as TOGAF, acknowledge the importance of requirements engineering in the development of enterprise architectures. Modelling support is needed to specify, document, communicate and reason about goals and requirements. Current modelling techniques for enterprise architecture focus on the products, services, processes and applications of an enterprise. In addition, techniques may be provided to describe structured requirements lists and use cases. Little support is available however for modelling the underlying motivation of enterprise architectures in terms of stakeholder concerns and the high-level goals that address these concerns. This paper describes a language that supports the modelling of this motivation. The definition of the language is based on existing work on high-level goal and requirements modelling and is aligned with an existing standard for enterprise modelling: the ArchiMate language. Furthermore, the paper illustrates how enterprise architecture can benefit from analysis techniques in the requirements domain

Hierarchical bounding structures for efficient virial computations: Towards a realistic molecular description of cholesterics

We detail the application of bounding volume hierarchies to accelerate second-virial evaluations for arbitrary complex particles interacting through hard and soft finite-range potentials. This procedure, based on the construction of neighbour lists through the combined use of recursive atom-decomposition techniques and binary overlap search schemes, is shown to scale sub-logarithmically with particle resolution in the case of molecular systems with high aspect ratios. Its implementation within an efficient numerical and theoretical framework based on classical density functional theory enables us to investigate the cholesteric self-assembly of a wide range of experimentally-relevant particle models. We illustrate the method through the determination of the cholesteric behaviour of hard, structurally-resolved twisted cuboids, and report quantitative evidence of the long-predicted phase handedness inversion with increasing particle thread angles near the phenomenological threshold value of $45^\circ$. Our results further highlight the complex relationship between microscopic structure and helical twisting power in such model systems, which may be attributed to subtle geometric variations of their chiral excluded-volume manifold

Towards a Framework for Managing Inconsistencies in Systems of Systems

The growth in the complexity of software systems has led to a proliferation of systems that have been created independently to provide specific functions, such as activity tracking, household energy management or personal nutrition assistance. The runtime composition of these individual systems into Systems of Systems (SoSs) enables support for more sophisticated functionality that cannot be provided by individual constituent systems on their own. However, in order to realize the benefits of these functionalities it is necessary to address a number of challenges associated with SoSs, including, but not limited to, operational and managerial independence, geographic distribution of participating systems, evolutionary development, and emergent conflicting behavior that can occur due interactions between the requirements of the participating systems. In this paper, we present a framework for conflict management in SoSs. The management of conflicting requirements involves four steps, namely (a) overlap detection, (b) conflict identification, (c) conflict diagnosis, and (d) conflict resolution based on the use of a utility function. The framework uses a Monitor-Analyze-Plan- Execute- Knowledge (MAPE-K) architectural pattern. In order to illustrate the work, we use an example SoS ecosystem designed to support food security at different levels of granularity

Basic tasks of sentiment analysis

Subjectivity detection is the task of identifying objective and subjective sentences. Objective sentences are those which do not exhibit any sentiment. So, it is desired for a sentiment analysis engine to find and separate the objective sentences for further analysis, e.g., polarity detection. In subjective sentences, opinions can often be expressed on one or multiple topics. Aspect extraction is a subtask of sentiment analysis that consists in identifying opinion targets in opinionated text, i.e., in detecting the specific aspects of a product or service the opinion holder is either praising or complaining about