Nikolaos Papadakis

Bio: Nikolaos Papadakis is an academic researcher from Army and Navy Academy. The author has contributed to research in topics: Information extraction & Web page. The author has an hindex of 6, co-authored 31 publications receiving 180 citations. Previous affiliations of Nikolaos Papadakis include National Technical University of Athens & University of Thessaly.

STAVIES: a system for information extraction from unknown Web data sources through automatic Web wrapper generation using clustering techniques

Abstract: A fully automated wrapper for information extraction from Web pages is presented. The motivation behind such systems lies in the emerging need for going beyond the concept of "human browsing". The World Wide Web is today the main "all kind of information" repository and has been so far very successful in disseminating information to humans. By automating the process of information retrieval, further utilization by targeted applications is enabled. The key idea in our novel system is to exploit the format of the Web pages to discover the underlying structure in order to finally infer and extract pieces of information from the Web page. Our system first identifies the section of the Web page that contains the information to be extracted and then extracts it by using clustering techniques and other tools of statistical origin. STAVIES can operate without human intervention and does not require any training. The main innovation and contribution of the proposed system consists of introducing a signal-wise treatment of the tag structural hierarchy and using hierarchical clustering techniques to segment the Web pages. The importance of such a treatment is significant since it permits abstracting away from the raw tag-manipulating approach. Experimental results and comparisons with other state of the art systems are presented and discussed in the paper, indicating the high performance of the proposed algorithm.

ISISEMD: Intelligent system for independent living and self-care of seniors with mild cognitive impairment or mild dementia

Abstract: According to the 2009 World Alzheimer Report, the number of people living with Alzheimer's and dementia is predicted to double almost every 20 years, and people will experience their first symptoms of dementia at an earlier age. In Europe the number of people with dementia is conservatively anticipated to increase by 40% over the next 20 years mainly due to the increase in the ageing population. As a consequence, social care providers in Europe will face major challenges over the next couple of decades due to the increased care demand for people suffering from dementia. This will have a double negative impact as it will not only increase the burden of care but also reduce the quality of life of informal carers helping those with pre- and mild dementia, living at home. Current traditional care provides limited services for these groups, leaving their needs unmet to a great extent. Information and communication technology (ICT) offers a number of promising opportunities to help patients with pre- and mild dementia live autonomously and safely in their own homes, and to support informal carers in coping with the care burden. ISISEMD is a European project aiming at improving the quality of life of elderly people with pre- and mild dementia living in their own homes, and also for their caregivers by offering innovative intelligent custom services. The services aim to support the needs of the elderly from this target group for: a) living safely at home; b) self-care by supporting their basic daily activities; c) daily interaction with relatives, friends and caregivers, giving them the feeling of safety and preventing their social isolation. The services will be validated via a controlled study across four European countries in real-life situations for one year. To address scalability, the pilot services will contain three complementary service bundles (basic services, intermediate and high level) that allow for escalation of the service provided to the end-users, based on their needs. The service bundles provided will be eas- ily managed, personalised, transparent and comprehensive. This paper elaborates on the ISISEMD approach for an innovative care model, including technical aspects of the services, the technologies used and the system architecture. It also describes plans for evaluation from a human factor perspective, and briefly discusses business opportunities.

SHIELD: A novel NFV-based cybersecurity framework

Abstract: SHIELD is an EU-funded project, targeting at the design and development of a novel cybersecurity framework, which offers security-as-a-Service in an evolved telco environment. The SHIELD framework leverages NFV (Network Functions Virtualization) and SDN (Software-Defined Networking) for virtualization and dynamic placement of virtualised security appliances in the network (virtual Network Security Functions - vNSFs), Big Data analytics for real-time incident detection and mitigation, as well as attestation techniques for securing both the infrastructure and the services. This papers discusses key use cases and requirements for the SHIELD framework and presents a high-level architectural approach.

Low Cost Omnidirectional Sound Source Utilizing a Common Directional Loudspeaker for Impulse Response Measurements

Abstract: Alternative low-cost sources (e.g., balloons, gun fires) are used for impulse response measurements when a dodecahedron speaker is not available. This study sets to explore the applicability of a method utilizing a common directional loudspeaker as a sound source. For this purpose measurements were performed in three spaces with three different common directional loudspeakers. Different placements of the loudspeakers were performed (twelve positions similar to the twelve positions of the faces of a dodecahedron speaker, different rotations of the loudspeakers for a total sum of twenty six and fourteen positions). The impulse responses obtained were added up creating a single impulse response for each case. Comparisons of the acoustic parameters measured with the proposed method and with a dodecahedron speaker are presented and suggest the expected mean absolute error and standard deviation for similar measurements. Reverberation time measurements show a mean absolute error of less than 0.08 s, as compared with measurements with a dodecahedron speaker. The proposed method can be the primary method for measuring impulse responses when a dodecahedron speaker is not available. Suggested improvements may lead to better omnidirectionality as compared with a dodecahedron loudspeaker, and set the method applicable to be utilized for auralization purposes.

Recurrent Neural Network for Approximate Earthquake Time and Location Prediction Using Multiple Seismicity Indicators

Abstract: This paper presents a computational approach for predicting the location and time of occurrence of future moderate-to-large earthquakes in an approximate sense based on neural network modeling and using a vector of 8 seismicity indicators as input. Two different methods are explored. In the first method, a large seismic region is subdivided into several small subregions and the temporal historical earthquake record is divided into a number of small equal time periods. Seismicity indicators are computed for each subregion for each time period and their relationship to the magnitude of the largest earthquake occurring in that subregion during the following time-period is studied using a recurrent neural network. In the second more direct approach, the temporal historical earthquake record is divided into a number of unequal time periods where each period is defined as the time between large earthquakes. Seismicity indicators are computed for each time-period and their relationship to the latitude and longitude of the epicentral location, and time of occurrence of the following major earthquake is studied using a recurrent neural network.

Seeing the wood for the trees. Carer related research and knowledge: A scoping review

Abstract: This NIHR-SSCR funded scoping review provides a comprehensive mapping of what is known about carers and caring, and aims to help inform policy, practice and research in relation to carers. The review was undertaken by searching 10 electronic bibliographic databases, supplemented by additional web searches to identify academic research, grey literature and wider knowledge. The analysis adopts a selective thematic approach covering: carer variables - the characteristics of different types of carer and different caring situations; types of care - the nature of needs of the cared for person and the features of the care situation; the impact of caring – resilience and coping, employment and health; and carer support and needs assessment. The final section highlights key messages identified from the review. It found that caring involves all sections and age groups of the population, with people are likely to experience one or more periods of caregiving over their lifetime. The uniqueness of each caring relationship is also highlighted. In relation to types of carers, knowledge about ‘hard to reach’ groups, such as BAME and LGBT carers, remains sparse. Older carers are also relatively invisible in policy and research terms. It found that much of the knowledge about carers identified in the review relates to their characteristics, their lived experience and the nature of their caregiving, with relatively less being known about the effectiveness of interventions to support them. The report concludes by offering suggestions for policy and practice. An appendix provides a bibliography of the 3,434 items identified in review, classified into 17 types of reference.

A Survey of Web Caching and Prefetching

Abstract: Web caching and prefetching are the most popular techniques that play a key role in improving the Web performance by keeping web objects that are likely to be visited in the near future closer to the client. Web caching can work independently or integrated with the web prefetching. The Web caching and prefetching can complement each other since the web caching exploits the temporal locality for predicting revisiting requested objects, while the web prefetching utilizes the spatial locality for predicting next related web objects of the requested Web objects. This paper reviews principles and some existing web caching and prefetching approaches. The conventional and intelligent web caching techniques are investigated and discussed. Moreover, Web prefetching techniques are summarized and classified with comparison limitations of these approaches. This paper also presents and discusses some studies that take into consideration impact of integrating both web caching and web prefetching together.