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Fractional Integration and Volatility Transmission Between Real Estate and Stock Markets: Novel Evidence from a FIGARCH-BEKK Approach
No full textThis paper examines the non-linear integration between the real estate and stock market for a series of developed markets namely UK, Germany, Australia, Hong-Kong, Japan, Singapore and the US. The period of analysis covers different market phases for these countries. We examine the volatility dynamics of the real estate and stock market in the UK and Germany within a novel FIGARCH-BEKK model. Our results reveal evidence of a common long-term fractional integration between real estate and stock market for these two countries. Moreover, when there is a lower common order of fractional integration, there might also be a significant bilateral or unilateral volatility spillover effect between real estate and stock market. Robustness tests confirm the consistency of the FIGARCH-BEKK model even during the global financial crisis. Additional tests capture the existence of volatility spillovers and fractional integration in the rest of countries (Australia, Hong-Kong, Japan, Singapore and the US) under examination. Our findings entail significant implications for investors and policy makers.66493996
Cyber range design framework for cyber security education and training
No full textThe need for effective training of cyber security personnel working in critical infrastructures and in the corporate has brought attention to the evolution of Cyber Ranges (CRs) as learning and training tools. Although CRs have been organized for many years, there is a lack of standards and common methodologies that facilitate their development and optimize their effectiveness. Aiming at strengthening cyber security education and research that utilize well designed CRs, we first analyze the CRs domain to identify key characteristics, strengths and fundamental weaknesses, and based on these outcomes we propose the Cyber Range Design Framework (CRDF), which includes the CR Architecture and the CR Life-Cycle. The CR Architecture presents the main components of CRDF compliant CRs, whereas the CR Life-Cycle presents the development phases of such approaches and the activities these phases embrace. CRDF builds on the Conceptual Framework for eLearning and Training (COFELET) and on the Exercise Life-Cycle. COFELET is particularly elaborated for the development of cyber security educational approaches, by adopting its design considerations that were based on widely adopted educational theories and approaches (e.g., scenario-based, reuse of elements). CRDF envisages the elaboration of CRs which optimize their impact, mitigate their weaknesses, and minimize their preparation and running costs. Under this prism, a preliminary appreciation of the CRDF approaches effectiveness is presented along with the expected outcomes of such approaches.2241005102
HapticSOUND: An Interactive Learning Experience with a Digital Musical Instrument
No full textIn this paper, an interactive learning experience is proposed, aiming to involve museum visitors in a personalized experience of the transmittal of cultural knowledge in an active and creative way. The proposed system, called HapticSOUND, consists of three subsystems: (a) the Information, where visitors are informed about the traditional musical instruments; (b) the Entertainment, where visitors are entertained by playing serious games to virtually assemble traditional musical instruments by a set of 3D objects; and (c) the Interaction, where visitors interact with a digital musical instrument which is an exact 3D-printed replica of a traditional musical instrument, where cameras have been placed to capture user gestures and machine learning algorithms have been implemented for gesture recognition. The museum visitor can interact with the lifelike replica to tactilely and aurally explore the instrument’s abilities, producing sounds guided by the system and receiving real-time visual and audio feedback. Emphasis is given to the Interaction Subsystem, where a pilot study was conducted to evaluate the usability of the subsystem. Preliminary results were promising since the usability was satisfactory, indicating that it is an innovative approach that utilizes sensorimotor learning and machine learning techniques in the context of playing sounds based on real-time gesture and fingering recognition.1312714
Visual programming and computational thinking environments for K-9 education: a systematic literature review
No full textTeaching programming and computational thinking to young students has gained increasing attention in recent years. This great attention is attributed partially to the emergence of easy-to-use visual programming environments. These environments help students focus on the logic and concepts of programming and at the same time enhance their engagement. It has been shown that the characteristics of visual programming environments influence students’ engagement with programming. However, there is still no systematic investigation of these characteristics. This study aims to provide insights on the characteristics of visual programming environments for K-9 education based on a systematic literature review of 83 empirical studies on K-9 teaching and learning programming. These characteristics are analysed based on the following four levels: a) functional features; b) student experience; c) teacher experience; d) disadvantages. Finally, herein we discuss the features that a programming environment for K-9 education could have to improve the experience of students and teachers.1819412
Addition and aggregative efficiency
No full textThe aim of this paper is to relate the condition for cost subadditivity to aggregative efficiency. In particular, we verify that subadditivity of the cost function occurs when aggregate cost efficiency is not less than the cost efficiency of the average production unit. This provides a simple way of examining the potential of merging two or more firms and of making inference about the extent of industry concentration. It also provides a simple nonparametric test for subadditivity of the cost function.59328128
SmartCLIDE design pattern assistant: A decision-tree based approach
No full textDesign patterns are well-known solutions to recurring design problems that are widely adopted in the software industry, either as formal means of communication or as a way to improve structural quality, enabling proper software extension. However, the adoption and correct instantiation of patterns is not a trivial task and requires substantial design experience. Some patterns are conceptually close or present similar design alternatives, leading novice developers to improper pattern selection, thereby reducing maintainability. Additionally, the mis-instantiation of a GoF (Gang-of-Four) design pattern, leads to phenomena such as pattern grime or architecture decay. To alleviate this problem, in this work we propose an approach that can help software engineers to more easily and safely select the proper design pattern, for a given design problem. The approach relies on decision trees, which are constructed using domain knowledge, while options are conveyed to software engineers through an Eclipse Theia plugin. To assess the usefulness and the perceived benefits of the approach, as well as the usability of the tool support, we have conducted an industrial validation study, using various data collection methods, such as questionnaires, focus groups, and task analysis. The results of the study suggest that the proposed approach is promising, since it increases the probability of the proper pattern being selected, and various useful future work suggestions have been obtained by the practitioners.5361304133
Skyline-Based Temporal Graph Exploration
No full textAn important problem in studying temporal graphs is detecting interesting events in their evolution, defined as time intervals of significant stability, growth, or shrinkage. We consider graphs whose nodes have attributes, for example in a network between individuals, the attributes may correspond to demographics, such as gender. We build aggregated graphs where nodes are grouped based on the values of their attributes, and seek for events at the aggregated level, for example, time intervals of significant growth between individuals of the same gender.We propose a novel approach based on temporal graph skylines. A temporal graph skyline considers both the significance of the event (measured by the number of graph elements that remain stable, are created, or deleted) and the length of the interval when the event appears. We also present experimental results of the efficiency and effectiveness of our approach.13985 LNCS88102Advances in Databases and Information System
A Machine Learning-Based Model for Epidemic Forecasting and Faster Drug Discovery
No full textToday, healthcare system models should have high accuracy and sensitivity so that patients do not have a misdiagnosis. For this reason, sufficient knowledge of the area is required, with the medical staff being able to validate the correctness of their decisions. Therefore, artificial intelligence (AI) in combination with other emerging technologies could provide many benefits in the medical sector. In this paper, we demonstrate the combination of Internet of Things (IoT) and cloud computing (CC) with AI-related techniques such as artificial intelligence (AI), machine learning (ML), deep learning (DL), and neural networks (NN) in order to provide a useful approach for scientists and doctors. Our proposed model makes use of these immersive technologies so as to provide epidemic forecasting and help accelerate drug and antibiotic discovery.122110766Application of Data Analytics in Smart Healthcar
A model of quality assurance in primary education management. The case of Greece
No full textThe paper validates a framework which is based on EFQM and associates quality criteria to results and outputs, reflecting the organization readiness and efficiency. The paper studies the views of school principals of Kindergarten and Elementary Schools in Greece. A nationwide survey provides a representative sample of 231 school principals who were administered an online questionnaire. The questionnaire was constructed by applying the EFQM framework as the basic pattern. Based on previous approaches which use PLS models in the education context, the paper provides findings on how key criteria of EFQM associate to each other when applied to the elementary education context in Greece. Findings provide evidence that EFQM criteria are indeed associated both directly and indirectly. The validation of the proposed model supports that the particular instrument can be used as a tool for continually assess, measure and improve the management procedures of elementary education organizations in order to have improved measures of key results criteria.91201655
A Reference Model for Cyber Threat Intelligence (CTI) Systems
No full textCyber Threat Intelligence (CTI) is a new but promising field of information security, with many organizations investing in the development of proper tools and services and the integration of CTI related information. However, as a new field, there is a lack of a conceptual framework with corresponding definitions. This paper discusses CTI complexity factors, proposes a set of definitions of the CTI key concepts and an eight-layer CTI Reference Model as a base for CTI systems design. In addition, the proposed reference model is validated by applying it to three case studies, producing the respective CTI Reference Architectures.119140