Spatial analysis of the Bronze Age sites of the region of Paphos in southwest Cyprus with the use of Geographical Information Systems - CAA

Surface analysis is also a very popular research area in GIS/Archaeology. I want to write more about Least-Cost Analysis in GIS later.

This work was mede by:
University of Cyprus, Archaeological Research Unit and Laboratory of Geophysical – Satellite Remote Sensing and Archaeo-environment, Institute for Mediterranean Studies, Foundation for Research and Technology




Part of Introcuction:

"The paper aims to study the Bronze Age site
distribution in the region of Paphos in SW Cyprus in
order to interpret site patterns. In the context of the
Paphos pilot project, entitled, “A long-term response
to the need to make modern development and the
preservation of the archaeo-cultural record mutually
compatible operations” (IACOVOU et al. 2009),
spatial analysis was performed, with the use of
Geographic Information Systems (GIS), on sites of
the Early, Middle and Late Cypriot period (3rd and
2nd millennium BC) that have been reported from
the region to this date...."

Underwater 3D shape reconstruction by fringe projection - CAA

Hallo everybody!

Sorry for the long time...

My second fovourite presentatiton was from CAA: "Underwater 3D shape reconstruction by fringe projection"
Great research at the University of Calabria, Italy (Bianco, G., Bruno, F., Muzzupappa, M., Luchi, M.L.).
Our Institute accomplished a big camera calibration project for underwater archaeological documentation, which was an interesting topic.


Part of Introcuction:

"....In this work, we have tested the effectiveness of a
whole-field structured light technique, based on
fringe projection, in underwater environment. The
Fringe Projection Technique (FPT) is widely used in
air (RASTOGI and GORTHI, 2010), and consists of
projection and acquisition of sinusoidal patterns on
the object (in the simplest case, one pattern is
enough). The system is composed by a video
projector and a digital camera, and the geometrical
setup is based on the principle of optical
triangulation. The recorded images are analyzed to
evaluate the phase-map of the object - which contains
the height information - with a signal processing
technique such as Fourier Transform (FT) , Wavelet
Transform (WT) , Windowed Fourier Transform
(WFT) , Spatial Phase Detection (SPD) or Phase
Stepping (PS). Any of these techniques of phase
measurement provides a discontinuous phase map of
the object (wrapped): so it becomes necessary to use
phase unwrapping in order to obtain a continuous
phase distribution (SURREL, 1998). By knowing the
intrinsic (focal distances, coordinates of the principal
points, and distortions) and extrinsic (relative
positions between the optical devises) parameters,
one can calculate the point clouds from the
triangulation between a optical ray of the camera (at
i,j pixel with phase value φi,j) and the relative plane
in the projector frame at the same phase value...."

Dynamic Models to Reconstruct Ancient Landscapes - CAA

"In this paper a method of landscape analysis is
demonstrated through raster-based digital elevation
models (DEM) using the case-study of the Helike
Delta, Gulf of Corinth, Greece. In the Classical
Period, Helike was the seat of the Achaean League
and the worship centre of the god Helikonian
Poseidon. With the focus on the earthquake and
tsunami of 373BC, DEMs are generated using
dynamic models of sea level rise, tectonic and pulse
tectonic uplift, subsidence, and sediment deposition.
Starting with a DEM from the present day
landscape, simulated DEM models are generated for
the Early Helladic (2500-2100BC), Classical (480-
323BC), Hellenistic (323-1st Century BC), and
Roman (1st Century BC – 4th Century AD) periods...."

This presentation was the first which I saw. Landscape reconstruction is a very popular research direction. We try to create new digital terrain models with surface analysis. After this step, it is possible to visualize the environment changes.

That was a great presentation from Mariza Kormann and Gary Lock, University of Oxford.

Workshop III - The CIDOC conceptual reference model as a tool for integrating cultural information - CAA

"This seminar is about the CIDOC Conceptual Reference Model (CRM), a top-level ontology and ISO standard (ISO21127:2006) for the semantic integration of cultural information. It will explain the scope and objectives of the model. It will detail the construction principles used and the major concepts it defines.

In order to use the model for information integration, multiple data structures have to be mapped to the model, so that data contents can be transformed automatically into a CRM compatible form and be merged. Alternatively, the mappings can be used to transform queries against the CRM into queries against local data structures. The mapping is the critical step, in which the domain expert’s knowledge is needed. IT tools can automatically execute later steps. The mapping process also shows compatibility with the CRM.

The seminar will explain in practical examples and exercises how to map a data structure to the CIDOC CRM."

I found the second and the third Workshop really interesting.

Open source software are in the focus of future work. MESHLAB is a also a great opensource program. Mesh and edit of point cloud are possible in this software.

Next days I want to present the most interesting works.

source: caa2010.org

Workshop II - An introduction to open source GIS: GRASS - CAA

"Grass is the leader open source GIS nowadays. It manage both raster and vector information, 2D and 3D models, and can be used on different operating systems and platforms. features more than 350 functions, including image processing, raster analysis, import and export, and vector and network analysis.

GIS are frequently used for archaeologist as a documentation tool, and also to analyse archaeological data. For this purpose it is necessary to have a powerful GIS system with a complete set of analysis tools.

Open source software is a wonderful choice for this purpose. As anyone can improve the system and add new functionality, open source systems are more dynamic.

One of the main characteristic of Grass GIS is that it can be operated, besides the usual graphical user interface, from the operating system shell. This provides it with a powerful scripting capability.

This workshop aims to introduce in a concise way the main functionality of Grass and its usage paradigms. Special attention will be devoted to the scripting capability. Basic GIS knowledge is required."

source: caa2010.org

Workshop I - Laser Scanner Systems for Archeological Surveys - CAA

"This workshop pretends to divulgate information on The State of the Art of the laser scanner technology as far as the software and hardware is concerned when solving the usual problems encountered on arqueological surveys.

To this end, we are limiting ourselves to the description of the features offered by a Laser Scanner system, model IMAGER 5006i, manufacturer by Z+F in Germany as well as the software programs JRC Reconstructor and Cloud Cube.

The problems we will focus on are the following:

• Logistic and portability of the equipment, in the concern that field work sites are not always easy to access
• Need of facing small and big objects with high accuracy

The IMAGER 5006i laser scanner concentrates its power on the following characteristics:

1. Very high speed in data acquisition combined with high resolution on the captured files. This feature makes it valid either for surveys of great targets at very far distances or when we are surveying small pieces at close range.
2. The system is very easy to set up and handle. The equipment can be configured without requiring any external connections. This feature is tremendously appreciated as far as the arqueological field work is concerned. Since the batteries, the data storage unit and the file configuration processor are part of the unit, it is not necessary to connect or use any other external complement to perform the data capture. This feature facilitates the work in scenarios which can be uncomfortable, far from urban areas and often of difficult access.
3. Capacity for data acquisition when working with targets coloured close to black.
4. Merging of images captured using the complementary camera with the scanner acquired data, in a integral and automatic fashion, for each of the scenes involved.

With regard to the software programs, we will discuss them in the same manner as we will discuss the hardware and we will try to demonstrate the tools which are used to solve the most common problems in handling the data acquired with the laser scanner: large files corresponding the huge clouds of points within the Auto Cad environment; how the final products are obtained, including profiles, cross sections, contours and volumes; all of them directly on DXF format or on some other CAD compatible systems.

Finally we will explain the working procedures and proper tools to be used to obtain the final products mentioned above: profiles, volumes, slopes, DTM, surface comparisons, and how to obtain the different results on DXF files or on files which are compatible with other CAD systems, in concrete we will discuss the following characteristics:

• Possibility of registering different files without requiring man-made marks, only using natural marks.
• Work aids to digitize plans, profiles and cross sections in general, starting with the cloud of points; all within the Auto CAD environment.
• Automatic generation of a wire mesh, over flats or curved surfaces by using average cross lines or cross planes.
• Integration of different data capture files in only one using a common reference system .
• Work aids to be used in the generation of a wire mesh.
• Registration of different survey files when the target has been changed in position or location while the scan files were being taken."

source: www.caa2010.org