Scenarios

Significant Environment Information to be extracted in the PERICLES case studies

This page illustrates the concept of Significant Environment Information with examples from the Digital Art and Space Science domains (the main areas of interest for the PERICLES stakeholders). Practical applications of these examples can be found on the experimental results page.

Software Based Artworks

The following use case example illustrates the Significant Environment Information investigation inspired by a Software Based Artworks scenario which we crated in cooperation with the Tate gallery, one of our PERICLES partners. In this example a Software Based Artwork should be migrated to a new computer system for the purpose of an exhibition. The software component of the Software Based Artwork causes a strong dependency on the computer system environment. A description of Software Based Artworks and an extensive study on their significant properties can be found in (Laurenson, 2014) and (Falcão, 2010).

We assume there is a computer system with a validated Software Based Artwork installation, which should be preserved to be able to configure and emulate the computer system environment as closely as possible for future exhibitions. The problem cannot be solved by preserving only the Software Based Artwork as a digital object, as the original appearance and behaviour of the software cannot be reconstructed based only on the metadata that belongs to the digital object. In the context of executing the artworks software for the exhibition installation are, for example, other dependencies, such as external libraries and applications, and data dependencies (data used at run-time by the Software Based Artwork). However, we have to look further into the whole environment to conceive all information that could be important for this scenario, as, for example, context-external running processes that can affect the availability of resources, or external network dependencies. The determination, extraction and preservation of Significant Environment Information are essential to solve the problem of enabling a future faithful emulation of the original system. An investigation of the environment information with influence on the significant properties of the digital object helps to identify the significant environment information for this use case.

An example of Significant Environment Information influencing the significant properties is when software changes the execution speed, based on the system resources, since program procedures can adapt their execution speed to the available resources depending on the programming style. This will turn information about system resources into Significant Environment Information for the purpose of “maintaining execution speed”. Information about display settings, as colour profile and resolution, used fonts, the graphics card and its driver is significant information that can affect the Software Based Artworks appearance (“render digital object with faithful appearance” purpose). Changes of programming language-related software can result in execution bugs or different speed of execution. The user interaction experience with the Software Based Artwork can be affected by the peripheral driver or setting or response times that are dependent on the execution speed.

In order to determine the Significant Environment Information, each Software Based Artwork has to be individually analysed, regarding the use purpose and based on the properties of the artwork and the artist’s beliefs regarding the significant properties of his artwork. Typical Significant Environment Information to emulate the environment for a Software Based Artwork is: information about computer system specifications, available resources, required resources, installed software and software dependencies. Other relevant dependencies to capture can be, for example, all the files that are used during the softwares execution, and peripheral dependencies, which can be identified by analysing peripheral calls of the Software Based Artwork. System resource requirements can be estimated on the basis of resource usage, but hardware changes come with the risk of affecting the software behaviour and should be avoided.

Another Significant Environment Information purpose is given, if the Software Based Artwork has to be recompiled because of a migration to another platform or to fix malfunctions with a different set of significance weights. Here the artworks behaviour has to be validated by the comparison of behaviour patterns measured at the original system continuously in a sheer curation setting. Examples for such measurements are processing timings, log outputs, operating system calls, calls of libraries and dependent external software, peripheral calls and commands, resource usage, user interaction, video and audio recordings. The two latter can also be used for validating the appearance of the artwork. If the SBA has a component of randomness, it is more difficult to evaluate its behaviour based on the measured patterns. Furthermore, information about the original development environment can be useful for a recompilation, and to identify the source of a malfunction.

Consequently, there is a great amount of accessible and potentially useful environment information. The decision of what to extract is often complicated by the fact that it is hard to foresee all further uses. Therefore, the whole environment (instead of only a current context) has to be considered, in order to identify the significant information to be extracted and preserved.

With the PERICLES Extraction Tool we address ways to extract Significant Environment Information from the environment in an automated fashion. In some cases the Significant Environment Information, though significant, lies outside of the scope of the information that can be captured automatically by our tool, and will require different approaches. One such example can be found in (Laurenson, 2014) (our emphasis): “Many software-based artworks depend on external links or dependencies. This might include links to websites, data sets, live events, sculptural components, or interfaces.”

Space science scenario

As one of the two main use cases, the PERICLES project is considering capturing and preserving information relating to measurements of the solar spectrum being carried out by the SOLAR payload of the International Space Station. The information includes operational data concerning the planning and execution of experiments, engineering documentation relating to the payload and ground systems, calibration data, and scientific measurements of experiments performed by solar scientists. The ultimate aim of SOLAR is to produce a fully calibrated set of solar observations, together with appropriate metadata.

We now consider three examples to illustrate the capture and use of Significant Environment Information.

In order to validate the experimental observations of the SOLAR instrument, it is necessary to understand the impact of many complex extraneous factors on the instrument. For example, vehicles visiting the ISS can affect the trajectory of the ISS itself and cause pollution and temperature changes. Such effects are often only uncovered by a long term analysis of the data by the scientists. Hence, there is a need to capture as much of the environment as possible at the time the observations are made to enable such analysis. This includes capturing a wide range of complex environment information relating to the instrument, the operational data, the payload sensors and events on the ISS itself. In this case, the purpose of Significant Environment Information is to enable critical analysis of the solar observations by the scientists. The significance weights reflect the influence the captured digital objects have on the critical analysis task. These weights can change over time as additional environmental factors may be uncovered that have an impact on the scientific data. The Significant Environment Information (at a given time) will therefore reflect the digital objects that are relevant to critical analysis with an appropriate weighting.

In order to validate the solar measurements made by the SOLAR instrument, frequent comparisons are made with data collected independently by other scientific teams. Often the techniques and instruments are different, which provides a good way to ensure the results are not subject to unwanted effects caused by the experimental methods used. The data from other teams and the comparisons that have been made are a valuable part of the environment metadata for the SOLAR data. The capturing of the validation experiments themselves can be performed by the PERICLES Extraction Tool and appropriate metadata will be created. This would include validation scripts and dependencies between subsets of the data, and would constitute (part of) the environment information. The purpose associated to the Significant Environment Information is the validation of the scientific data by the science community. The significance weights reflect the value of specific data objects in the validation of the SOLAR dataset. The Significant Environment Information can assist scientists in assessing the quality and reliability of the data produced.

A third example relating to the PERICLES science case study relates to the operational data for the SOLAR experiment, which is primarily created, managed and used by the mission operators, who operate the experiments on ISS remotely from the ground station. The operations data includes the planning, telemetry and operations logs. Given the huge complexity and volume of the space mission information, a major issue for the operators is information overload. An important task for the operators is to resolve anomalies, which occur when the normal operational parameters of the instrument are exceeded, such as overheating. Identifying and resolving anomalies often requires extensive research in the archived operations data and documentation. The problem that the operators often have is not that the information is not available, just that there is so much documentation that it is difficult and time consuming to locate information that relates to a specific problem (i.e. further contextual information). Only specific parts of the documentation are relevant, but this has to be learnt from experience as this type of information is not formally documented. In this case, the digital object to be preserved is the catalogue of known anomalies and the environment information is the aggregation of all operations data. The purpose for the Significant Environment Information is the identification of a specific anomaly. In this case, the significance weights indicate the relevance of a specific digital object, such as a piece of documentation for the instrument or an excerpt from the archived telemetry to the particular anomaly. Thus the Significant Environment Information provides a way to indicate all the environment information relevant to identifying and debugging a specific anomaly.

Laurenson, P. (2014). Old media, new media? Significant difference and the conservation of software-based art. In Graham, B. (Ed.) New Collecting: Exhibiting and Audiences after New Media Art. Chapter 3. University of Sunderland, UK

Falcão, P. (2010). Developing a Risk Assessment Tool for the conservation of software-based artworks. MA thesis, BFH. Bern: Hochschule der Künste Bern.

Have also a look at our deliverabe for the background of Significant Environment Information. The deliverable will be published soon at the PERICLES website.