Trajectory Representation in Location-Based Services: Problems and Solution

Recently, much work has been done in feasibility studies on services offered to moving objects in an environment equipped with mobile telephony, network technology and GIS. However, despite of all work on GIS and databases, the situations in which the whereabouts of objects are constantly monitored and stored for future analysis are an important class of problems that present-day database/GIS has difficulty to handle. Considering the fact that data about whereabouts of moving objects are acquired in a discrete way, providing the data when no observation is available is a must. Therefore, obtaining a "faithful representation" of trajectories with a sufficient number of discrete (though possibly erroneous) data points is the objective of this research

The Ecological Approach to Information Processing

Imagine a 5-stone weakling whose brain has been loaded with all the knowledge of a champion tennis player. He goes to serve in his first match – Wham! – His arm falls off. The 5-stone weakling just doesn’t have the bone structure or muscular development to serve that hard. There are, clearly, different types of knowledge/ability/skill, only some of which are a matter of what can be transferred simply by passing signals down a wire from one brain (or computer) to another. Sometimes it is the body (the hardware) which knows

Dynamic management for business processes modeling & execution in workflows

Contemporary workflow-management systems cannot represent change or evolution of business processes. When a change is needed due to external reason, an offline procedure is invoked in order to create a new workflow engine template for the future instances in the workflow enactment module. The standard interfaces do not deal with the business process metadata in a way that can actually change it as a reaction to inbound knowledge. There are many relevant cases, especially in the virtual enterprise arena, where the business process is not deterministic and is influenced by external parameters (such as the selection of virtual partners), so the knowledge of what should be done is available, however it is external to the system. There is a need to develop a modeling mechanism that enables to transfer process definitions in an automatic way, without the need for human interference. One way of confronting with these issues is the use of a rule-based engine to monitor business process execution. This engine will contain internal meta-rules that refer to metadata entities, i.e. rules that describe how to act on other rules (business process routing) when a change is detected, while executing all needed consistency checks

A comparative application of Jacobi and Gauss Seidel’s numerical algorithms in page rank analysis

In PageRank calculation the Jacobi matrix is given by d T (damping factor times transition matrix), a sparse matrix. The solution of the iteration is x, if the limit exists. The convergence is guaranteed, if the absolute value of thelargest eigen value of ƒv1ƒ{ Mƒw is less than one. In case of PageRank calculation this is fulfilled for 0< d < 1. An improved Gauss-Seidel iteration algorithm, based on the decomposition M ƒ­ D ƒy L ƒyU where D, L and U are the diagonal, lower triangular and upper triangular parts of M would yield x D ƒvL x U x bƒw i i i ƒ­ ƒ{ ƒy ƒy ƒy ƒy 1* * * 1 1 . Introducing a relaxation parameter £f ¡Ú 0 leads to a generalization of the Gauss-Seidel methodx ƒv ƒwx D ƒvL x U x bƒw i i i i ƒ­ ƒ{ ƒy ƒ{ ƒy ƒy ƒy ƒy 1 1* * * 1 1 ƒÜ ƒÜ . This work compares the two methods with a C++ code numerically

The Simple Publishing Interface (SPI)

Ternier, S., Massart, D., Totschnig, M., Klerkx, J., & Duval, E. (2010). The Simple Publishing Interface (SPI). D-Lib Magazine, September/October 2010, Volume 16 Number 9/10, doi:10.1045/september2010-ternierThe Simple Publishing Interface (SPI) is a new publishing protocol, developed under the auspices of the European Committee for Standardization (CEN) workshop on learning technologies. This protocol aims to facilitate the communication between content producing tools and repositories that persistently manage learning resources and metadata. The SPI work focuses on two problems: (1) facilitating the metadata and resource publication process (publication in this context refers to the ability to ingest metadata and resources); and (2) enabling interoperability between various components in a federation of repositories. This article discusses the different contexts where a protocol for publishing resources is relevant. SPI contains an abstract domain model and presents several methods that a repository can support. An Atom Publishing Protocol binding is proposed that allows for implementing SPI with a concrete technology and enables interoperability between applications.European Committee for Standardization (CEN), CEN/Expert/2009/3

Language-Based Access to Large Sensor Repositories

Sensor data have broadened their scope recently, ranging now from the simple time series measurements to, e.g., hyperspectral satellite image maps timeseries. In addition to observed data, simulation data increasingly have to be merged, for example 4-D ocean and atmospheric data. The majority of these data fall into the category of multi-dimensional rasters. However, when it comes to flexible retrieval, including sensor data search, aggregation, analysis, fusion, etc., standard query language support in the past has not kept up with the service level of, e.g., metadata retrieval. To close this gap, the Open GeoSpatial Consortium (OGC) has issued the Web Coverage Processing Service (WCPS) Standard in December 2008. WCPS defines a request language for multi-dimensional raster data, suitable for specifying navigation, download, and analysis of sensor, image, and statistics data. This contribution emphasises sensor data modeling and the perspectives for an integrated, cross-dimensional sensor data retrieval. Further, the WCPS reference implementation is briefly discussed