Schlagwort-Archive: GIS

Ph. D. Project: Towards a conceptual reference model for archaeological information within the context of Geographic Information System

By Michelle Pfeiffer:

The aim of the thesis is to contribute to the development of a conceptual reference model for archaeological information by investigating the underlying principles of archaeological information, in the context of Geographic Information Systems (GIS).
Data are the basis of any scientific empirical investigation. They are the formalized reinterpretable representation of information acquired through observation or measuring processes. Archaeological data occupy in this context at twofold hand a rather peerless position within sciences. The often-unique character of the data acquisition process (e.g. excavation), due to its destructive and consequently unrepeatable nature, makes out of archaeological data an irretrievable documentation of past human presence, looming furthermore archaeology’s epistemological foundation. Moreover, it is particularly the complex ontic nature of an archaeological object, that shapes the archaeological data in a distinctive manner. Both aspects allow qualifying archaeological data as being spatio-temporal, imperfect, heterogeneous, multiscale and multimodal.
Albeit long-term investigations and recent research progresses, Geographic Information Systems are still immature in handling archaeological data. One major reason for this inability stems from the inchoate and insufficient conceptual framework to which GIS applications may refer within archaeology. Information Systems and as such Geographic Information Systems need to be tailored in respect to ontic and epistemic information characteristics to become fully exploitable within their application domain. This requires a consistent conceptual model of the domain knowledge. Since the way in which data are conceptualized, is pivotal as to how an Information System might fulfil its functions. It defines its informative, memorative but also its active functions by means of information retrieval, access, handling and analysing – an often highly underestimated fact.
In striving for a conceptual reference model conceptual modeling is deployed- a common method within computer science. Conceptual modeling seeks representing real world phenomena by an abstraction process in form of a conceptual model. Thereby domain specific concepts and their mutual relation, as well as their behavioural and structural aspects need to be identified, defined and constructed. Considering the increasing importance of Information Systems, and GIS in particular, within archaeology, one might thus be surprised, although the fundamental importance of a conceptual framework, that the investigations in this sense have been minor within archaeology.

Scrutinizing archaeological objects from a conceptual perspective requires reasoning about their ontic nature. This gives rise to a range of issues including: What defines an archaeological object? How does it behave in space? How does it evolve over time? Does change affect an object’s identity? These are some of the questions investigated in the context of the thesis. Thereby the study expects contributing to an enhanced conceptual understanding of archaeological data.

2 Doctoral Scholarships in “Archaeological Information Systems” and “GIScience/Geoinformatics”

The Junior Research Group “Digital Humanities/Digital Cultural heritage” of the Cluster of Excellence “Asia and Europe in a Global Context,” in cooperation with the “Heidelberg Graduate School for Mathematical and Computational Methods in the Sciences”, offers two doctoral scholarships with focus on “Archaeological Information Systems” and “Digital Cultural heritage”.

Within the framework of the research group we will look at discourses linked to changes of new possibilities in the use of digital methods in archeology. Opportunities and risks associated with big research data sets will be ascertained. This results in standardized workflows that serve further investigations. We work on a team with GIS and laser scan data (2D and 3D modeling) in cooperation with a research network of various institutions within a digital research infrastructure. And we also develop VREs (Virtual Research Environments) for specific digitalization workflows of sub-projects in archaeology.

The successful applicants’ primary task will be to complete a PhD degree, but active participation in relevant graduate courses offered at the Cluster of Excellence or other institutes at Heidelberg University is recommended. The stipends are rated at € 1200 to 1468/month. Access to travel and publication funding is available.

Candidates must hold an M.A. or equivalent in a relevant discipline of Pre- and Early History (“Ur- und Frühgeschichte”), Historical Sciences, GIScience /Geoinformatics, Landscape Archaeology and Geomatics or Archaeological Information Systems (“Archäoinformatik”) etc. and experience in archaeological fieldwork methods in Europe and/or Asian contexts. Proficiency in English is mandatory. German and French language skills are desirable. An interest in interdisciplinary collaboration is essential.

To apply, send curriculum vitae, academic transcripts, an outline of a dissertation project (2-3 pages) related to the research group, names and contact details of two referees, and one written sample (altogether in one PDF) via email to Dr. Armin Volkmann (armin.volkmann[at]asia-europe.uni-heidelberg.de). Stipend start should be in 2013, review of applications will continue until the positions are filled.

Heidelberg University is an equal opportunity/affirmative-action employer. In case of equality of qualification and suitability of applicants, the applications made by female researchers will be given preferential consideration. We also encourage and welcome applications from disabled persons.

For additional information see: http://www.asia-europe.uni-heidelberg.de/en

How to identify climate signals within a GIS site catchment analysis

In the River Oder region, an abandonment of the settlements of the migration period has been identified. As the archaeological finding site analysis shows, the region was virtually uninhabited from 450 to 700 AD. Was an ecological crisis the reason for that exodus? Unfortunately, we have only very few scientific data sets from the German-Polish border region. So I had to find new ways to generate arguments and answer this question. By a systematic site catchment analysis I could find out signals of the paleoclimate. They are the evidence of dramatic climate fluctuations. And this is the biggest reason of the emigration of the inhabitants. At the same time the results of the site catchment analysis are the base for a predictive modeling with has clearly defined areas of high and low probabilities of finding sites.

In the context of the present study, an analysis in a GIS of sites from the Iron Age to the Early Middle Ages was applied to the River Oder Region. A site catchment analysis of the topographical setting, the soil and broader parameters was conducted as a GIS examination. In this the spatial data information in a probable operating radius around the respective settlements of the individual periods was collected and evaluated statistically. In this way, statistically significant climate proxies on the relative humidity index and temperature pattern of the paleoclimate could be demonstrated. Through the use of weighted average means it was possible to describe climate signals of the compared periods. The quantitative analysis of the data of more than 500 finding sites allows identifying significant signals. As a result I found out that at the end of the Iron Age and at the beginning of the migration period, dramatic climate fluctuations are recognized. The climate fluctuations are the main reason for emigration out of this region. In the migration period, and again at the end of the Iron Age, the region was virtually uninhabited for 250 years. The data from the site catchment analysis is in a next step the base for a predictive modeling with has clearly defined areas of high and low probabilities of finding sites.

A site catchment analysis of the topographical setting, the soil and broader parameters was conducted as a GIS examination, in which the spatial data information in a probable operating radius around the respective settlements of the individual periods was collected and evaluated statistically. In this way, statistically significant climate proxies on the relative humidity index and temperature pattern of the paleoclimate could be demonstrated. In addition, the deciding location factors of the soil and the geoecological environment of the settlement as well as distortionary anthropogenic and natural superimpositions were discussed. The ecological indicator values were rearranged into concise categories in a transformation process in consideration of their usability and informative value for matters concerning prehistoric, agronomically orientated cultures and checked for climate signals.  The identified climate signals do not represent absolute data, but rather indirect, relative data, which permit comparative statements concerning the previous and subsequent level.

With the use of comparative climate research, palynology, dendrochronology, the status of glaciers, river levels and models of paleotemperature, the climate signals that were produced in the context of the GIS environmental analysis could be verified. In this way, the probability and concision of the environmental analysis developed here and its particularly detailed chronological value were substantiated.

The final step of the GIS analysis is based on Voronoi diagrams of the sites mapped as prehistoric space models. They show concepts of space in time. In a cartographic reconstruction of settlement clusters, the relationship between the anthropogenically influenced agricultural area and extensive natural forest areas was visualised. These methods are a part for the predictive modeling to clarify for example the most interesting regions of the settlements in the migration period.

http://armin-volkmann-geoarchaeology.de/