Daniel Harezlak

The Collage Authoring Environment

Abstract The Collage Authoring Environment is a software infrastructure which enables domain scientists to collaboratively develop and publish their work in the form of executable papers. It corresponds to the recent developments in both e-Science and computational technologies which call for a novel publishing paradigm. As part of this paradigm, static content (such as traditional scientific publications) should be supplemented with elements of interactivity, enabling reviewers and readers to reexamine the reported results by executing parts of the software on which such results are based as well as access primary scientific data. Taking into account the presented rationale we propose an environment which enables authors to seamlessly embed chunks of executable code (called assets) into scientific publications and allow repeated execution of such assets on underlying computing and data storage resources, as required by scientists who wish to build upon the presented results. The Collage Authoring Environment can be deployed on arbitrary resources, including those belonging to high performance computing centers, scientific e-Infrastructures and resources contributed by the scientists themselves. The environment provides access to static content, primary datasets (where exposed by authors) and executable assets. Execution features are provided by a dedicated engine (called the Collage Server) and embedded into an interactive view delivered to readers, resembling a traditional research publication but interactive and collaborative in its scope. Along with a textual description of the Collage environment the authors also present a prototype implementation, which supports the features described in this paper. The functionality of this prototype is discussed along with theoretical assumptions underpinning the proposed system.

Exploratory programming in the virtual laboratory

GridSpace 2 is a novel virtual laboratory framework enabling researchers to conduct virtual experiments on Grid-based resources and other HPC infrastructures. GridSpace 2 facilitates exploratory development of experiments by means of scripts which can be written in a number of popular languages, including Ruby, Python and Perl. The framework supplies a repository of gems enabling scripts to interface low-level resources such as PBS queues, EGEE computing elements, scientific applications and other types of Grid resources. Moreover, GridSpace 2 provides a Web 2.0-based Experiment Workbench supporting development and execution of virtual experiments by groups of collaborating scientists. We present an overview of the most important features of the Experiment Workbench, which is the main user interface of the Virtual laboratory, and discuss a sample experiment from the computational chemistry domain.

Managing entire lifecycles of e-science applications in the gridspace2 virtual laboratory --- from motivation through idea to operable web-accessible environment built on top of PL-Grid e-infrastructure

The GridSpace2 environment, developed in the scope of the PL-Grid Polish National Grid Initiative, constitutes a comprehensive platform which supports e-science applications throughout their entire lifecycle. Application development may involve multiple phases, including writing, prototyping, testing and composing the application. Once the application attains maturity it becomes operable and capable of being executed, although it may still be subject to further development --- including actions such as sharing with collaborating researchers or making results publicly available with the use of dedicated publishing interfaces. This paper describes each of these phases in detail, showing how the GridSpace2 platform can assist the developers and publishers of computational experiments.

Virtual Laboratory for Development and Execution of Biomedical Collaborative Applications

The ViroLab Virtual Laboratory is a collaborative platform for scientists representing multiple fields of expertise while working together on common scientific goals. This environment makes it possible to combine efforts of computer scientists, virology and epidemiology experts and experienced physicians to support future advances in HIV-related research and treatment. The paper explains the challenges involved in building a modern, inter-organizational platform to support science and gives an overview of solutions to these challenges. Examples of real-world problems applied in the presented environment are also described to prove the feasibility of the solution.

A distributed multiscale computation of a tightly coupled model using the Multiscale Modeling Language

Abstract Nature is observed at all scales; with multiscale modeling, scientists bring together several scales for a holistic analysis of a phenomenon. The models on these different scales may require significant but also heterogeneous computational resources, creating the need for distributed multiscale computing. A particularly demanding type of multiscale models, tightly coupled, brings with it a number of theoretical and practical issues. In this contribution, a tightly coupled model of in-stent restenosis is first theoretically examined for its multiscale merits using the Multiscale Modeling Language (MML); this is aided by a toolchain consisting of MAPPER Memory (MaMe), the Multiscale Application Designer (MAD), and Gridspace Experiment Workbench. It is implemented and executed with the general Multiscale Coupling Library and Environment (MUSCLE). Finally, it is scheduled amongst heterogeneous infrastructures using the QCG-Broker. This marks the first occasion that a tightly coupled application uses distributed multiscale computing in such a general way.

Distributed Multiscale Computations Using the MAPPER Framework

We present a global overview of the methodology developed within the MAPPER European project to design, implement and run a multiscale simulation on a distributed supercomputing infrastructure. Our goal is to highlight the main steps required when developing an application within this framework. More specifically, we illustrate the proposed approach in the case of hydrology applications. A performance model describing the execution time of the application as a function of its spatial resolution and the hardware performance is proposed. It shows that Distributed Multiscal Computation is beneficial for large scale problems.

InSilicoLab --- managing complexity of chemistry computations

InSilicoLab is an application portal designed to support in silico experiments by easily running computational software on Grids. Unlike manual job submission or grid portals, InSilicoLab enables its users to run complex computations without technical knowledge of how to operate the grid resources. Instead, the users may focus only on the information and activities relevant to their research. This paper is a result of a feasibility study of applying the InSilicoLab concept to the domain of computational chemistry. It, therefore, includes a study of chemistry computations and their realisation in InSilicoLab, as well as a description of the generic architecture of the environment.

Composing, execution and sharing of multiscale applications

This paper presents the research which led to elaboration of an environment for composing, executing and sharing multiscale applications. The resulted environment supports ability to connect software modules to form large-scale, multiscale simulations and directly execute them on distributed e-infrastructures suitable for particular application models chosen by users. It also enables hybrid execution, i.e. different parts of the same application can be executed on various types of e-infrastructures i.e. on a grid (e.g. EGI), HPC (e.g. PRACE) or on a cloud. The environment is web based and gives the user a direct access to the distributed resources from a single browser. It supports a variety of possible realizations of multiscale simulations in a unified and non-invasive way and enables storing model metadata such as scale, inputs and outputs.The presented environment consists of an application composition tool called Multiscale Application Designer (MAD), an application module description registry MAPPER Memory (MaMe) and GridSpace (GS) supporting execution of applications on various infrastructures. We present an architecture of the current implementation along with a detailed description of the tools and their current features. Additionally, we report on validation of our tools by multiscale application developers. We compare the processes of creating and running applications with and without the tools and we present a case study based on a sample multiscale application skeleton. Environment supporting composition and sharing of multiscale applications.Direct execution of multiscale applications on distributed e-infrastructures.Support for hybrid execution on different types of e-infrastructures.Support for a variety of realizations of multiscale simulations in a non-invasive way.Validation by multiscale application developers.

Support for Multiscale Simulations with Molecular Dynamics

We present a reusable solution that supports users in combining single-scale models to create a multiscale application. Our approach applies several multiscale programming tools to allow users to compose multiscale applications using a graphical interface, and provides an easy way to execute these multiscale applications on international production infrastructures. Our solution extends the general purpose scripting approach of the GridSpace platform with simple mechanisms for accessing production resources, provided by the Application Hosting Environment (AHE). We apply our support solution to construct and execute a multiscale simulation of clay-polymer nanocomposite materials, and showcase its benefit in reducing the effort required to do a number of time-intensive user tasks.

A New Approach to Development and Execution of Interactive Applications on the Grid

This paper presents an approach to development of interactive Grid applications used in the application development platform (Appea), currently under development. The presented environment enables smooth and reliable development of such applications, integrating various types of Web and Grid services as well as data sources spread over a distributed infrastructure. However, the users to which Appea caters require that such applications be capable of interactivity and require human actors to interact with them. The addition of interactivity requirements has not thus far been sufficiently addressed in the Grid domain and indeed many popular Grid middleware platforms do not take sufficient notice of this problem. Therefore, the aim of this paper is to describe how such aspects of user interactivity are supported by the Appea platform and how they correspond to the needs of end users of Grid applications. The paper presents the motivation behind the proposed solution, a conceptual design of Appea as well as its basic architecture. In addition, a use case is presented, showing how the solution can be applied to a real-life workflow.