The activity of the archaeologist is related to the correct interpretation of several information sources. When the information sources comes from the field work, raises a problem related to the digitalization and treatment of the large amount of information produced in the field. This information is typically hand written by an expert, and some months later processed by another person who might not understand exactly the notes produced in the field. From this process, we see major problems:
With these problems in mind, we developed a distributed architecture to support the archaeological activity, at the office and at the field. The primary concept is to get the field work done in a digital platform:
Our system is based on a central GIS, where all colleted data is stored and maintained. Before any field work, the user can select the related data (maps, table subsets, etc) and load it on his PDA. During the field work this data can by enlarged and improved, and it will be integrated in the central repository when returning from the site. According to the recently PDA features, the data can be remotely synchronized and more data can be downloaded, using a GPRS connection, for example. The synchronization process tries to transfers the minimum amount of information as possible, to make it possible over slow connections (like GPRS).
MAGIS was developed for mobile platforms, so that data collection can occur in the place where the object is found. Due to hardware and technological limitations, the solution has been created using some different programs: a SVG Viewer(MAGIS-Viewer); a database interface (MAGIS-Mobile); and a middleware (MAGIS-Deamon) that connects the MAGIS-Viewer with the database.
It is possible to store (and retrieve) data in a server. It is possible due to the MAGIS-Manager, which is an application that synchronizes the data in the mobile application and the server, using SQL Server 2000 and SQL Server 2000 CE gateway.
MAGIS-Viewer is a viewer that allows the graphic visualization of SVG files in mobile platforms. It was created in Java, which provides an hardware independence.
The MAGIS-Viewer has these features:
MAGIS-Mobile is the database interface; it provides all forms to construct and maintain the archaeological database, allowing the registry of all information about the discovery. Using MAGIS-Viewer the explorer introduces a reference to a new finding (artefact), locating it in the map. If he do not fulfill all data at the moment, he can finish it later, using MAGIS-Mobile.
MAGIS-Mobile recognizes all pendents registers and alerts the user to finish the process. It enables the user to store all non-graphical information, without MAGIS-Viewer.
The database is supported by SQL Server CE, and a module was written in C# . Due to this, program only runs on platforms with Microsoft .NET Compact Framework installed. The choice of that language was based in two arguments: on one hand Java does not have a direct access to SQL Server CE and there is no any JBDC driver for SQL Server CE, and on the other hand, C# has a direct access to SQL Server CE.
MAGIS-Deamon is the simplest of the programs. Written in C# , it can have a direct access to SQL Server CE database. It works listening a socket. When receives a stream in the socket (from MAGIS-Viewer), it processes the message, creating a SELECT or INSERT string, and executes the command. When the result is known, MAGIS-Deamon converts it into a string and sends it back, through the socket, to the MAGIS-Viewer.
MAGIS-Manager is a program residing in the server that supports the central database. It has two main functionalities: it is responsible for the synchronization when the archaeologist downloads his PDA database; allows the archaeologist to select for the central database to upload to PDA.