Nima Kaviani

Ontologies and Software Engineering

The chapter analyzes the state of the art in the use of ontologies for various software engineering tasks. The chapter starts from defining software engineering as an application context for ontologies. Next, it introduces a framework that identifies places in software lifecycle where ontologies can contribute to improvethe current state of software engineering.

On metamodeling in megamodels

Model-Driven Engineering (MDE) introduced the notion of metamodeling as the main means for defining modeling languages. As a well organized engineering discipline, MDE should also have its theory clearly defined in terms of the relationships between key MDE concepts. Following the spirit of MDE, where models are first class citizens, even the MDE theory can be defined by models, or so called megamodels. In this paper, we use Favres megamodel that was already used for defining linguistic metamodeling. Starting from the premise that this megamodel can also be used for defining other MDE concepts, we use it to specify the notion of ontological metamodeling. Here, we show that in order for this megamodel to be able to fully capture all the concepts of ontological metamodeling, some refinements should be applied to its definition. We also show how these new changes are in the same direction with the work of Kühne in defining linguistic and ontological metamodels.

AUTOMATED STAGED CONFIGURATION WITH SEMANTIC WEB TECHNOLOGIES

Since the introduction in the early nineties, feature models receive a great deal of attention in industry and academia. Industrial success stories in applying feature models for modeling software product lines, and using them for configuring software-intensive systems motivate academia to discover ways to integrate different feature dependencies into the feature model, and automate verified feature configuration. In this paper we demonstrate how ontologies and Semantic Web technologies facilitate seamless integration of required external services and deployment platform capabilities into the feature model. Furthermore, we also contribute with an algorithm for automating staged configuration using Semantic Web reasoners to discover unfeasible features of the feature model.

Investigating distributed user interfaces across interactive large displays and mobile devices

The use of a dual mobile and large screen approach offers a number of intriguing possibilities including a potential solution to the problem of managing conflicts that arise when a large screen is shared in a public setting. Here, we report on a series of experiments carried out to determine quantitative or qualitative effects of user performance when interaction is split across large public and smaller private screens. Our position is that using mobile devices as an auxiliary device for interaction can boost user experience when interacting with large displays.

Web Rule Languages to Carry Policies

Recent efforts in the area of Web policy languages show concerns on how to better represent both context and rules of a domain to deal with large number of resources and users and let them interact. Web rule languages have been recently introduced as a means to facilitate interactions between parties with dissimilar policies and business rules. In this paper, we introduce REWERSE rule markup language (R2ML) as a Web rule language that can be employed to make concepts, policies, and elements of a domain digestible by another domain through the use of vocabularies, rules, and annotations. We also show how R2ML elements can model the concepts and elements of different policy languages.

Cross-tier application and data partitioning of web applications for hybrid cloud deployment

Hybrid cloud deployment offers flexibility in trade-offs between the cost-savings/scalability of the public cloud and control over data resources provided at a private premise. However, this flexibility comes at the expense of complexity in distributing a system over these two locations. For multi-tier web applications, this challenge manifests itself primarily in the partitioning of application- and database-tiers. While there is existing research that focuses on either application-tier or data-tier partitioning, we show that optimized partitioning of web applications benefits from both tiers being considered simultaneously. We present our research on a new cross-tier partitioning approach to help developers make effective trade-offs between performance and cost in a hybrid cloud deployment. In two case studies the approach results in up to 54% reduction in monetary costs compared to a premise only deployment and 56% improvement in execution time compared to a naive partitioning where application-tier is deployed in the cloud and data-tier is on private infrastructure.

ReCoIn: A framework for dynamic integration of remote services into a service-oriented component model

Having the notion of services brought into the domain of component based software design has enriched the domain of modular self-contained components with support for loose coupling, dynamic runtime discovery, and late binding. However, loose coupling, runtime discovery, and composition for a service-oriented component model in its current scale mostly applies to homogeneous services that admit to the specifications of the original service component model. This design is in conflict with the initial outlook of SOA in which reusability of existing services is considered a primary goal. In this paper, we discuss ReCoIn, a remote service composition and integration framework, which aims to bring functionalities of traditional Web services into the local repository of a service oriented component model. We discuss how ReCoIn enables remote Web services to be properly discovered, encapsulated, and used in a service oriented component model framework, offering better service reuse and fault tolerance. In this paper, we layout the overall architectural design for ReCoIn and present its initial prototype.

Model-Driven Engineering of a General Policy Modeling Language

Despite many efforts in developing policy languages which work in different logical domains and with various reasoning engines, there has been limited attention paid to bringing policy definition, design, and integration into the realm of the mainstream software development process. There seems to be a lack of appropriate software development tooling that can allow for easy representation and integration of policies with other pieces of software at the design time. This paper presents a general policy modeling language (GPML), following the rationale of model driven engineering (MDE), as a means to design policies and integrate them to the software development process. We describe the logical foundation and the modeling rationale behind GPML and show how it is adjustable to the existing policy languages.

Partitioning of web applications for hybrid cloud deployment

Hybrid cloud deployment offers flexibility in trade-offs between the cost-savings/scalability of the public cloud and control over data resources provided at a private premise. However, this flexibility comes at the expense of complexity in distributing a system over these two locations. For multi-tier web applications, this challenge manifests itself primarily in the partitioning of application- and database-tiers. While there is existing research that focuses on either application-tier or data-tier partitioning, we show that optimized partitioning of web applications benefits from both tiers being considered simultaneously. We present our research on a new cross-tier partitioning approach to help developers make effective trade-offs between performance and cost in a hybrid cloud deployment. The general approach primarily benefits from two technical improvements to integer-programming based application partitioning. First, an asymmetric cost-model for optimizing data transfer in environments where ingress and egress data-transfer have differing costs, such as in many infrastructure as a service platforms. Second, a new encoding of database query plans as integer programs, to enable simultaneous optimization of code and data placement in a hybrid cloud environment. In two case studies the approach results in up to 54% reduction in monetary costs compared to a premise only deployment and 56% improvement in response time compared to a naive partitioning where the application-tier is deployed in the public cloud and the data-tier is on private infrastructure.

Profiling-as-a-Service: adaptive scalable resource profiling for the cloud in the cloud

Runtime profiling of Web-based applications and services is an effective method to aid in the provisioning of required resources, for monitoring service-level objectives, and for detecting implementation defects. Unfortunately, it is difficult to obtain accurate profile data on live client workloads due to the high overhead of instrumentation. This paper describes a cloud-based profiling service for managing the tradeoffs between: (i) profiling accuracy, (ii) performance overhead, and (iii) costs incurred for cloud computing platform usage. We validate our cloud-based profiling service by applying it to an open-source e-commerce Web application.