A Min Tjoa

E-Commerce and Web Technologies

Existing electronic negotiation systems (ENSs) typically implement a single, fixed negotiation protocol, which restricts their use to negotiation problems that were anticipated and established a priori by the system designers. The single-protocol restriction limits ENSs’ applicability in experiments and in many real-life negotiation situations. ENSs that allow for the use of different protocols also allow for the customization to users’ needs and abilities. We present theoretical foundations for the design of flexible and highly customizable protocol-driven ENSs. Our design enables researchers and negotiators to map negotiation activities onto system components and to construct their own negotiation protocols by creating a sequence of layout programs invoking components and rules. * This work was supported with grants from the Initiative for New Economy of the Social Sciences and Humanities Research Council Canada, and the Natural Science and Engineering Research Council Canada. e-negotiations 2004 2

The prognostic relevance of various factors at the time of the first admission of the patient: Retrospective DÖSAK study on carcinoma of the oral cavity

In a retrospective study, on a sample of 1021 patients with carcinoma of the lips, oral cavity and oropharynx, the clinically available factors at the time of the patients first admission are analysed with reference to their prognostic relevance. Prognostically relevant factors are determined by both univariate and multivariate analyses. Of the 18 factors analysed, the following seven finally proved to be prognostically relevant: tumour size, degree of infiltration, degree of histological differentiation and site by organ of the primary tumour, the combination of evidence + clinical appearance + degree of fixation of the regional lymph nodes, age of the patient, and evidence of distant metastases. On the basis of these results it will be possible to create a prognostic index. This prognostic index should be eligible for use in clinical practice, as opposed to usual classification models.

Sense & response service architecture (SARESA): an approach towards a real-time business intelligence solution and its use for a fraud detection application

The dynamic business environment of many organizations require massive monitoring of their processes in real-time in order to proactively respond to exceptional situations and to take advantage of time-sensitive business opportunities. The ability to sense and interpret events about a changing business environment requires an event-driven IT infrastructure for pwerforming fast and well-informed decisions and putting them into action. However, traditional Business Intelligence (BI) and Data Warehousing technologies do not directly address time sensitive monitoring and analytical requirements. We introduce an enhanced BI architecture that covers the complete process to sense, interpret, predict, automate and respond to business environments and thereby aims to decrease the reaction time needed for business decisions. We propose an event-driven IT infrastructure to operate BI applications which enable real-time analytics across corporate business processes, notifies the business of actionable recommendations or automatically triggers business operations, and effectively closing the gap between Business Intelligence systems and business processes. A scenario from the area of mobile phone fraud detection was chosen for building a prototype that illustrates the proposed approach by using current available IT technologies.

An Object Oriented Multidimensional Data Model for OLAP

Online Analytical Processing (OLAP) data is frequently organized in the form of multidimensional data cubes each of which is used to examine a set of data values, called measures, associated with multiple dimensions and their multiple levels. In this paper, we first propose a conceptual multidimensional data model, which is able to represent and capture natural hierarchical relationships among members within a dimension as well as the relationships between dimension members and measure data values. Hereafter, dimensions and data cubes with their operators are formally introduced. Afterward, we use UML (Unified Modeling Language) to model the conceptual multidimensional model in the context of object oriented databases.

Transformation of Requirement Specifications Expressed in Natural Language into an EER Model

A tool for conceptual design is introduced which transforms requirement specifications in natural language into concepts of the EER model. The transformation is based on the assumption that the meaning of data modeling concepts can be derived from structures of natural language. A parsing algorithm which accesses information of a grammar and a lexicon is designed to meet the requirements of the tool. The parsing results are processed further on by rules and heuristics which set up a relationship between linguistic and design knowledge. The design tool works interactively to handle information which is ambigous, incomplete or redundant.

A security concept for OLAP

A data warehouse collects and integrates data from multiple, autonomous, heterogeneous sources with the purpose of efficiently implementing decision support or OLAP queries. Much working data warehousing has been performed on view materialization and data integration, we focus on access and security management in OLAP and N-dimensional cube. Since data in data warehouse are valuable and an important cooperate resource, we define a security model for data warehouses which describes security constrains for roles in the data warehouse. Each user in the data warehouse has a role and each role has a security constrain list that builds the security profile of the role. According these role profile the user is authorized to query data from the data warehouse.

UbiqLog: a generic mobile phone-based life-log framework

Smartphones are conquering the mobile phone market; they are not just phones; they also act as media players, gaming consoles, personal calendars, storage, etc. They are portable computers with fewer computing capabilities than personal computers. However, unlike personal computers, users can carry their smartphone with them at all times. The ubiquity of mobile phones and their computing capabilities provide an opportunity of using them as a life-logging device. Life-logs (personal e-memories) are used to record users’ daily life events and assist them in memory augmentation. In a more technical sense, life-logs sense and store users’ contextual information from their environment through sensors, which are core components of life-logs. Spatio-temporal aggregation of sensor information can be mapped to users’ life events. We propose UbiqLog, a lightweight, configurable, and extendable life-log framework, which uses mobile phone as a device for life logging. The proposed framework extends previous research in this field, which investigated mobile phones as life-log tool through continuous sensing. Its openness in terms of sensor configuration allows developers to create flexible, multipurpose life-log tools. In addition to that, this framework contains a data model and an architecture, which can be used as reference model for further life-log development, including its extension to other devices, such as ebook readers, T.V.s, etc.

EurAsia-ICT 2002: Information and Communication Technology

This paper deals with the problem of updating reference models and decision thresholds in speaker verification. In the real application of a speaker verification system, reference models of speakers and their decision thresholds should be already determined. Reference model and decision threshold updating can render a speaker verification system more robust against inter-session variability, due to changes in speaker’s voice and the diversity in transmission line characteristics. In this paper, different methods for the calculation of decision threshold, the updating of decision threshold and reference model, and BMDR decision criterion are compared and evaluated. In our experiments, Sphericity Measure (a Second Order Statistical Measure) was implemented and used for speaker modeling.

Capturing Delays and Valid Times in Data Warehouses—Towards Timely Consistent Analyses

Real-world changes are generally discovered delayed by computer systems. The typical update patterns for traditional data warehouses on an overnight or even weekly basis increase this propagation delay until the information is available to knowledge workers. Typically, traditional data warehouses focus on summarized data (at some level) rather than detailed data.For active data warehouse environments, detailed data about entities is required for checking the data conditions and triggering actions to automize routine decision tasks. Hence, keeping data current (by minimizing the latency from when data is captured until it is available to knowledge workers) and consistent in that context is a difficult task.In this paper we present an approach for modeling conceptual time consistency problems and introduce a data model that deals with timely delays. It supports knowledge workers in finding out, why (or why not) an active system responded to acertain state of the data. Therefore, the model enables analytical processing of detailed data (enhanced by valid time) based on a knowledge state at a specific time. All states that were not yet known by the system at that point in time are consistently ignored. This enables timely consistent analyses by considering that the validity of detailed data and aggregates can be restricted to time intervals only, due to frequent updates and late-arriving information.

Novel mediator architectures for Grid information systems

Virtualization is one of the key features of the Grid. As data-intensive applications gain on importance, it becomes crucial for the success of the Grid to provide transparent access to distributed/heterogeneous data sources as well. In this paper, we describe our concepts to provide a Virtual Data Source (VDS) - a logically single homogeneous data source - on the Grid. Various data sources like relational/XML databases and comma separated value files can be combined via a Mapping Schema. By allowing to invoke user defined functions during the mediation a flexible way of resolving heterogeneities is provided. To show the feasibility of the developed concepts and elaborate the basis for a dynamic version they have been seamlessly integrated into OGSA-DAI to provide a non-proprietary, centralized and easy to integrate solution.