The Digital Puglia Project: An Active Digital Library of Remote Sensing Data

The growing need of software infrastructure able to create, maintain and ease the evolution of scientific data, promotes the development of digital libraries in order to provide the user with fast and reliable access to data. In a world that is rapidly changing, the standard view of a digital library as a data repository specialized to a community of users and provided with some search tools is no longer tenable. To be effective, a digital library should be an active digital library, meaning that users can process available data not just to retrieve a particular piece of information, but to infer new knowledge about the data at hand. Digital Puglia is a new project, conceived to emphasize not only retrieval of data to the client's workstation, but also customized processing of the data. Such processing tasks may include data mining, filtering and knowledge discovery in huge databases, compute-intensive image processing (such as principal component analysis, supervised classification, or pattern matching) and on demand computing sessions. We describe the issues, the requirements and the underlying technologies of the Digital Puglia Project, whose final goal is to build a high performance distributed and active digital library of remote sensing data

Implementation of a General Web Application Program Interface for Geoinformatics

C++ language was used for creating web applications at the department of Mapping and Cartography for many years. Plenty of projects started to be very large-scale and complicated to maintain. Consequently, the traditional way of adding functionality to a Web Server which previously has been used (CGI programs) started being usefulness. I was looking for some solutions - particularly open source ones. I have tried many languages (solutions) and finally I chose the Java language and started writing servlets. Using the Java language (servlets) has significantly simplified the development of web applications. As a result, developing cycle was cut down. Because of Java JNI (Java Native Interface) it is still possible to use C++ libraries which we are using. The main goal of this article is to share my practical experiences with rewriting typical CGI web application and creating complex geoinformatic web application

WebFlow - A Visual Programming Paradigm for Web/Java Based Coarse Grain Distributed Computing

We present here the recent work at NPAC aimed at developing WebFlow---a general purpose Web based visual interactive programming environment for coarse grain distributed computing. We follow the 3-tier architecture with the central control and integration WebVM layer in tier-2, interacting with the visual graph editor applets in tier-1 (front-end) and the legacy systems in tier-3. WebVM is given by a mesh of Java Web servers such as Jeeves from JavaSoft or Jigsaw from MIT/W3C. All system control structures are implemented as URL-addressable servlets which enable Web browser-based authoring, monitoring, publication, documentation and software distribution tools for distributed computing. We view WebFlow/WEbVM as a promising programming paradigm and coordination model for the exploding volume of Web/Java software, and we illustrate it in a set of ongoing application development activities

Complete instrumentation requirements for performance analysis of web based technologies

In this paper we present the eDragon environment, a research platform created to perform complete performance analysis of new Web-based technologies. eDragon enables the understanding of how application servers work in both sequential and parallel platforms offering a new insight in the usage of system resources. The environment is composed of a set of instrumentation modules, a performance analysis and visualization tool and a set of experimental methodologies to perform complete performance analysis of Web-based technologies. This paper describes the design and implementation of this research platform and highlights some of its main functionalities. We will also show how a detailed analytical view can be obtained through the application of a bottom-up strategy, starting with a group of system events and advancing to more complex performance metrics using a continuous derivation process.We acknowledge the European Center for Parallelism of Barcelona (CEPBA) and CEPBA-IBM Research Institute (CIRI) for supplying the computing resources for our experiments. This work is supported by the Ministry of Science and Technology of Spain and the European Union (FEDER funds) under contract TIC2001–0995-C02–0 I and by Direcció General de Recerca of the Generalitat de Catalunya under grant 2001FI 00694 UPC APTIND.Peer ReviewedPostprint (author's final draft

Migrating existing multimedia courseware to Moodle

Open source course management systems offer increased flexibility for instructors and instructional designers. Communities can influence the development of these systems and on an individual basis, the possibility to modify the system software exists. Migrating existing courseware to these systems can therefore be beneficial, sometimes even required. We report here about our experience in migrating an existing courseware system consisting of multimedia content and interactive, integrated infrastructure functionality to an open source course management system called Moodle. We will assess the difficulties that we have encountered during this process and, discuss the importance of standards in this context, and we aim to provide other instructors or instructional designers with guidelines and assessment support for other migration projects

Evolution and Paradigm Shift in Distributed System Architecture

New age programming languages highlight the mobility of objects and on-the-fly communication mechanism even being available on nodes with intermittent connections. We are breathing in the era where the working framework enables the procedures to oversee imparted information and arrangement to a domain where distinctive procedures are executing on discrete frameworks that essentially makes use of message-based correspondence or mobile communication architecture. The highlight that has been conceived for the years has spawned the remote administration and remote access in distributed computing framework and was outlined as an approach to digest the strategy call component to use between frameworks associated through a system. These frameworks contains the stub and skeleton on client and server side respectively which behaves as remote proxies and deals with marshaling and unmarshalling of the incoming and outgoing data. This has incurred the need of more distributed and platform independent communication mechanisms, that can not only make intercalling of functions but also support features like platform independency from various object oriented based programming languages. The distinctions in the programming model prompt higher state of abilities and more implicit customer side mechanisms for simple and hands-on interaction with the code that actualizes and implements the distributed frameworks