Search results for " Information systems"

Stochastic dynamical modelling of spot freight rates

2014

Based on empirical analysis of the Capesize and Panamax indices, we propose different continuous-time stochastic processes to model their dynamics. The models go beyond the standard geometric Brownian motion, and incorporate observed effects like heavy-tailed returns, stochastic volatility and memory. In particular, we suggest stochastic dynamics based on exponential Levy processes with normal inverse Gaussian distributed logarithmic returns. The Barndorff-Nielsen and Shephard stochastic volatility model is shown to capture time-varying volatility in the data. Finally, continuous-time autoregressive processes provide a class of models sufficiently rich to incorporate short-term persistence …

Spatial analysis of the relationship between mortality from cardiovascular and cerebrovascular disease and drinking water hardness

2004

Journal Article; Research Support, Non-U.S. Gov't; Reproduced with permission from Environmental Health Perspectives. Previously published scientific papers have reported a negative correlation between drinking water hardness and cardiovascular mortality. Some ecologic and case-control studies suggest the protective effect of calcium and magnesium concentration in drinking water. In this article we present an analysis of this protective relationship in 538 municipalities of Comunidad Valenciana (Spain) from 1991-1998. We used the Spanish version of the Rapid Inquiry Facility (RIF) developed under the European Environment and Health Information System (EUROHEIS) research project. The strateg…

Simulation models in eGovernment using system dynamics: A literature survey

2016

System Dynamics (SD) is a method to build simulation models using computers, to study the behaviour of systems, and apply what-if scenarios aiming at achieving optimal policy design. To have an overview of the current state-of-the-art of SD use in the eGovernment field; we have surveyed related literature. Our main goal is to uncover the possibilities for future research by clarifying the shortages. The identified literature is not very large. In most of the literature, SD models use was limited to SD practitioners. We discovered low usage of Group Model Building and workshops despite their usefulness in involving non-SD practitioners in the model building process. Additionally, there is a …

Affordances and effects of introducing social media within eParticipation-Findings from government-initiated Indonesian project

2018

The Current State of Social Media Research for eParticipation in Developing Countries: A Literature Review

2016

While there is an increasing interest for conducting research on the importance of social media within the eParticipation area, more emphasis is still needed within the context of developing countries. We address this need by presenting a literature review on social media within eParticipation in developing countries, to add to the understanding of how these technologies influence the political environment. We discuss trends, contributions and challenges within this area, and propose a future research agenda. Furthermore, we propose a model of social media for eParticipation from a process view perspective to guide future research in this field.

Robust Graph Topology Learning and Application in Stock Market Inference

2019

In many applications, there are multiple interacting entities, generating time series of data over the space. To describe the relation within the set of data, the underlying topology may be used. In many real applications, not only the signal/data of interest is measured in noise, but it is also contaminated with outliers. The proposed method, called RGTL, infers the graph topology from noisy measurements and removes these outliers simultaneously. Here, it is assumed that we have no information about the space graph topology, while we know that graph signal are sampled consecutively in time and thus the graph in time domain is given. The simulation results show that the proposed algorithm h…

Identifying Unreliable Sensors Without a Knowledge of the Ground Truth in Deceptive Environments

2017

This paper deals with the extremely fascinating area of “fusing” the outputs of sensors without any knowledge of the ground truth. In an earlier paper, the present authors had recently pioneered a solution, by mapping it onto the fascinating paradox of trying to identify stochastic liars without any additional information about the truth. Even though that work was significant, it was constrained by the model in which we are living in a world where “the truth prevails over lying”. Couched in the terminology of Learning Automata (LA), this corresponds to the Environment (Since the Environment is treated as an entity in its own right, we choose to capitalize it, rather than refer to it as an “…

E-health progresses in Romania

2006

The paper is presenting the recent evolution of e-health aspects in Romania. Data presented are based on governmental reports. Surveys organized by the "Lucian Blaga" University of Sibiu and studies carried on by the national Institute for Research and Development in Informatics (I.C.I.) have shown that Romania has important health problems, from cardio vascular diseases (CVD) to cancer and infectious diseases, a high score on mortality and morbidity and a low one on natality. Poor management of the health sector did not help to solve all these problems. In the last 14 years there were several attempts to reform healthcare but none succeeded until now. The health insurance system is operati…

Looking for representative fit models for apparel sizing

2014

This paper is concerned with the generation of optimal fit models for use in apparel design. Representative fit models or prototypes are important for defining a meaningful sizing system. However, there is no agreement among apparel manufacturers and each one has their own prototypes and size charts i.e. there is a lack of standard sizes in garments from different apparel manufacturers. We propose two algorithms based on a new hierarchical partitioning around medoids clustering method originally developed for gene expression data. We are concerned with a different application; therefore, the dissimilarity between the objects has to be different and must be designed to deal with anthropometr…

An integrated identity verification system for mobile terminals

2005

PurposeTo report the work on the design of an integrated identity verification system architecture aimed at approaching high verification accuracy, continuous security, and user‐friendliness.Design/methodology/approachThe reported research corresponds to the building process in the design science research paradigm. The requirements to an identity verification system are defined and used in the selection of architecture components. Furthermore, various issues affecting the suitability of component distribution between a terminal and a remote server are considered.FindingsIn order to meet the stated requirements, in the proposed architecture static and dynamic identity verification is combine…