Christopher A. Lee

A framework for contextual information in digital collections

Future users of digital objects will likely have numerous tools for discovering preserved digital objects relevant to their interests, but making meaningful use and sense of the digital objects will also require contextual information. This paper provides an analysis of context, distinguishing three main ways in which that term has been used within the scholarly literature. I then discuss contextual information within digital collections. I present a framework for contextual information that is based on nine classes of contextual entities: object, agent, occurrence, purpose, time, place, form of expression, concept/abstraction, and relationship. The paper then discusses existing standards and guidance documents for encoding information related to the nine classes of contextual entities, and it concludes with a discussion of potential implications for descriptive practices through the lifecycle of digital objects. “Always design a thing by considering it in its next larger context—a chair in a room, a room in a house, a house in an environment, an environment in a city plan.” - Eliel Saarinen (The Maturing Modern, 1956) “…if life is going to exist in a Universe of this size, then the one thing it cannot afford to have is a sense of proportion.” - Douglas Adams (1980)

Selection and context scoping for digital video collections: an investigation of youtube and blogs

Digital curators are faced with decisions about what part of the ever-growing, ever-evolving space of digital information to collect and preserve. The recent explosion of web video on sites such as YouTube presents curators with an even greater challenge - how to sort through and filter a large amount of information to find, assess and ultimately preserve important, relevant, and interesting video. In this paper, we describe research conducted to help inform digital curation of on-line video. Since May 2007, we have been monitoring the results of 57 queries on YouTube related to the 2008 U.S. presidential election. We report results comparing these data to blogs that point to candidate videos on YouTube and discuss the effects of query-based harvesting as a collection development strategy.

Defining what digital curators do and what they need to know: the digccurr project

The DigCCurr (Digital Curation Curriculum) project is developing a graduate level curricular framework, course modules, and experiential components to prepare students for digital curation in various environments. This paper summarizes a draft and guiding principles behind a matrix of digital curation knowledge and competencies, which are serving as the basis for our curriculum design efforts.

Extending digital repository architectures to support disk image preservation and access

Disk images (bitstreams extracted from physical media) can play an essential role in the acquisition and management of digital collections by serving as containers that support data integrity and chain of custody, while ensuring continued access to the underlying bits without depending on physical carriers. Widely used today by practitioners of digital forensics, disk images can serve as baselines for comparison for digital preservation activities, as they provide fail-safe mechanisms when curatorial actions make unexpected changes to data; enable access to potentially valuable data that resides below the file system level; and provide options for future analysis. We discuss established digital forensics techniques for acquiring, preserving and annotating disk images, provide examples from both research and educational collections, and describe specific forensic tools and techniques, including an object-oriented data packaging framework called the Advanced Forensic Format (AFF) and the Digital Forensics XML (DFXML) metadata representation.

Query parameters for harvesting digital video and associated contextual information

Video is increasingly important to digital libraries and archives as both primary content and as context for the primary objects in collections. Services like YouTube not only offer large numbers of videos but also usage data such as comments and ratings that may help curators today make selections and aid future generations to interpret those selections. A query-based harvesting strategy is presented and results from daily harvests for six topics defined by 145 queries over a 20-month period are discussed with respect to, query specification parameters, topic, and contribution patterns. The limitations of the strategy and these data are considered and suggestions are offered for curators who wish to use query-based harvesting.

Keeping the context: an investigation in preserving collections of digital video

Summary form only given. This poster presents an information model for digital video context and places the information model within the context of recent guidance on metadata for digital video, metadata for digital preservation, and the reference model for an open archival information system (OAIS)

Digital Preservation Metadata Practice for Disk Image Access

Many libraries, archives, and museums are now regularly acquiring, processing, and analyzing born-digital materials. Materials exist on a variety of source media, including flash drives, hard drives, floppy disks, and optical media. Extracting disk images (i.e., sector-by-sector copies of digital media) is an increasingly common practice. It can be essential to ensuring provenance, original order, and chain of custody. Disk images allow users to explore and interact with the original data without risk of permanent alteration. These replicas help institutions to safeguard against modifications to underlying data that can occur when a file system contained on a storage medium is mounted, or a bootable medium is powered up. Retention of disk images can substantially reduce preservation risks. Digital storage media become progressively difficult (or impossible) to read over time, due to “bit rot,” obsolescence of media, and reduced availability of devices to read them. Simply copying the allocated files off a disk and discarding the storage carrier, however, can be problematic. The ability to access and render the content of files can depend upon the presence of other data that resided on the disk. These dependencies are often not obvious upon first inspection and may only be discovered after the original medium is no longer readable or available. Disk images also enable a wide range of potential access approaches, including dynamic browsing of disk images (Misra S, Lee CA, Woods K (2014) A Web Service for File-Level Access to Disk Images. Code4Lib Journal, 25 [3]) and emulation of earlier computing platforms. Disk images often contain residual data, which may consist of previously hidden or deleted files (Redwine G, et al. in Born digital: guidance for donors, dealers, and archival repositories. Council on Library and Information Resources, Washington, 2013 [4]). Residual data can be valuable for scholars interested in learning about the context of creation. Traces of activities undertaken in the original environment—for example, identifying removable media connected to a host machine or finding contents of browser caches—can provide additional sources of information for researchers and facilitate the preservation of materials (Woods K, et al. in Proceedings of the 11th annual international ACM/IEEE joint conference on digital libraries, pp. 57–66, 2011 [5]). Digital forensic tools can be used to create disk images in a wide range of formats. These include raw files (such as those produced by the Unix tool dd). Quantifying successes and failures for many tools can require judgment calls by qualified digital curation professionals. Verifying a checksum for a file is a simple case; the checksums either match or are different. In the events described in the previous sections, however, the conditions for success are fuzzier. For example, fiwalk will often “successfully” complete whether or not it is able to extract a meaningful record of the contents of file system(s) on a disk image. Likewise, bulk_extractor will simply report items of interest it has discovered. Knowing whether this output is useful (and whether it has changed between separate executions of a given tool) depends on comparison of the output between the two runs, information not currently recorded in the PREMIS document. In the BitCurator implementation, events are often recorded as having completed, rather than as having succeeded, to avoid ambiguity. Future iterations of the implementation may include more nuanced descriptions of event outcomes.