52 research outputs found

    60 років базам даних (заключна частина)

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    Наводиться огляд досліджень і розробок баз даних із моменту їх виникнення в 60-х роках минулого століття і по сьогодні. Виділяються наступні етапи: виникнення і становлення, бурхливий розвиток, епоха реляційних баз даних, розширені реляційні бази даних, постреляційні бази даних і великі дані. На етапі становлення описуються системи IDS, IMS, Total і Adabas. На етапі бурхливого розвитку висвітлені питання архітектури баз даних ANSI/X3/SPARC, пропозицій КОДАСИЛ, концепції і мов концептуального моделювання. На етапі епохи реляційних баз даних розкриваються результати наукової діяльності Е. Кодда, теорія залежностей і нормальних форм, мови запитів, експериментальні дослідження і розробки, оптимізація та стандартизація, управління транзакціями. Етап розширених реляційних баз даних присвячений опису темпоральних, просторових, дедуктивних, активних, об’єктних, розподілених та статистичних баз даних, баз даних масивів, машин баз даних і сховищ даних. На наступному етапі розкрита проблематика постреляційних баз даних, а саме: NOSQL, ключ-значення, стовпчикові, документні, графові, NewSQL, онтологічні. Шостий етап присвячений розкриттю при- чин виникнення, характерних властивостей, класифікації, принципів роботи, методів і технологій великих даних. Нарешті, в останньому із розділів подається короткий огляд досліджень і розробок баз даних у Радянському СоюзіThe article provides an overview of research and development of databases since their appearance in the 60s of the last century to the present time. The following stages are distinguished: the emergence formation and rapid development, the era of relational databases, extended relational databases, post-relational databases and big data. At the stage of formation, the systems IDS, IMS, Total and Adabas are described. At the stage of rapid development, issues of ANSI/X3/ SPARC database architecture, CODASYL proposals, concepts and languages of conceptual modeling are highlighted. At the stage of the era of relational databases, the results of E. Codd’s scientific activities, the theory of dependencies and normal forms, query languages, experimental research and development, optimization and standardization, and transaction management are revealed. The extended relational databases phase is devoted to describing temporal, spatial, deductive, active, object, distributed and statistical databases, array databases, and database machines and data warehouses. At the next stage, the problems of post-relational databases are disclosed, namely, NOSQL-, NewSQL- and ontological databases. The sixth stage is devoted to the disclosure of the causes of occurrence, characteristic properties, classification, principles of work, methods and technologies of big data. Finally, the last section provides a brief overview of database research and development in the Soviet Union

    24th Nordic Conference on Computational Linguistics (NoDaLiDa)

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    MLIC: Multi-Reference Entropy Model for Learned Image Compression

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    Recently, learned image compression has achieved remarkable performance. The entropy model, which estimates the distribution of the latent representation, plays a crucial role in boosting rate-distortion performance. However, most entropy models only capture correlations in one dimension, while the latent representation contain channel-wise, local spatial, and global spatial correlations. To tackle this issue, we propose the Multi-Reference Entropy Model (MEM) and the advanced version, MEM+^+. These models capture the different types of correlations present in latent representation. Specifically, We first divide the latent representation into slices. When decoding the current slice, we use previously decoded slices as context and employ the attention map of the previously decoded slice to predict global correlations in the current slice. To capture local contexts, we introduce two enhanced checkerboard context capturing techniques that avoids performance degradation. Based on MEM and MEM+^+, we propose image compression models MLIC and MLIC+^+. Extensive experimental evaluations demonstrate that our MLIC and MLIC+ models achieve state-of-the-art performance, reducing BD-rate by 8.05%8.05\% and 11.39%11.39\% on the Kodak dataset compared to VTM-17.0 when measured in PSNR.Comment: Fixed some typos and re-organized the pape

    Advances in Image Processing, Analysis and Recognition Technology

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    For many decades, researchers have been trying to make computers’ analysis of images as effective as the system of human vision is. For this purpose, many algorithms and systems have previously been created. The whole process covers various stages, including image processing, representation and recognition. The results of this work can be applied to many computer-assisted areas of everyday life. They improve particular activities and provide handy tools, which are sometimes only for entertainment, but quite often, they significantly increase our safety. In fact, the practical implementation of image processing algorithms is particularly wide. Moreover, the rapid growth of computational complexity and computer efficiency has allowed for the development of more sophisticated and effective algorithms and tools. Although significant progress has been made so far, many issues still remain, resulting in the need for the development of novel approaches

    System for surveillance of maritime traffic using the network of over-the-horizon radars

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    Ova disertacija se bavi optimizacijom i prilagođenjem algoritama za praćenje ciljeva za potrebe ublažavanja uticaja štetnih refleksija na proces praćenja ciljeva kod izahorizontskih radara sa površinskim talasom (HFSW radari), upotrebljenih za osmatranje pomorskih ciljeva i konceptualizacijom i realizacijom sistema za integrisano pomorsko praćenje ciljeva baziranog na HFSWR mrežama.This dissertation deals with the optimization and adaptation of target tracking algorithms to mitigate the impact of harmful reflections on the target tracking process in over-the-horizon high frequency surface wave radar (HFSW radar), used to observe maritime targets and conceptualize and implement an integrated maritime surveillance system based on HFSWR networks..

    Mobile Ad-Hoc Networks

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    Being infrastructure-less and without central administration control, wireless ad-hoc networking is playing a more and more important role in extending the coverage of traditional wireless infrastructure (cellular networks, wireless LAN, etc). This book includes state-of-the-art techniques and solutions for wireless ad-hoc networks. It focuses on the following topics in ad-hoc networks: quality-of-service and video communication, routing protocol and cross-layer design. A few interesting problems about security and delay-tolerant networks are also discussed. This book is targeted to provide network engineers and researchers with design guidelines for large scale wireless ad hoc networks

    Recent Development of Hybrid Renewable Energy Systems

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    Abstract: The use of renewable energies continues to increase. However, the energy obtained from renewable resources is variable over time. The amount of energy produced from the renewable energy sources (RES) over time depends on the meteorological conditions of the region chosen, the season, the relief, etc. So, variable power and nonguaranteed energy produced by renewable sources implies intermittence of the grid. The key lies in supply sources integrated to a hybrid system (HS)

    Emerging Communications for Wireless Sensor Networks

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    Wireless sensor networks are deployed in a rapidly increasing number of arenas, with uses ranging from healthcare monitoring to industrial and environmental safety, as well as new ubiquitous computing devices that are becoming ever more pervasive in our interconnected society. This book presents a range of exciting developments in software communication technologies including some novel applications, such as in high altitude systems, ground heat exchangers and body sensor networks. Authors from leading institutions on four continents present their latest findings in the spirit of exchanging information and stimulating discussion in the WSN community worldwide

    Medial Transformations: Theorising the Intelligent Mediation Sphere

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    Media are playing significant roles in the context of the contemporary world. They are deeply interwoven with many aspects of life. The relationships between contemporary media and societies and cultures are complex. Therefore, theorising media situation is a challenging endeavour. The central goals of the current book are to review the ontological and epistemological shifts in medium theories, to theorise contemporary media and critically examine the ‘new’ media practices. In a nutshell, the discussions revolve around three areas of media ontology, media typology and media practices. Media ontology addresses the concepts and definitions of media at a meta-level. The concept of media can be defined either positive – media as a particular technology or cultural/communicational means – or negative – media as complex sets of medial relations or mediation processes. In the current book, media are defined as mediation processes, sets of non-linear mediated formations in transformations (a dynamic-organic state of ‘becoming’ cultural events, media situations, mediated environments and mediation sphere). Media cannot be reduced to certain modalities or technological characteristics, rather they ‘set the shape, pace, rhythms, and typography’ of cognitive, communicational, cultural, social, biopolitical life in temporal and spatial living environment. This definition can provide a holistic approach for categorisation of media. In chapter one, the frameworks of arguments are further discussed in detail. Chapter two, three and four encompass the critical analysis of pre-medium, medium and post-medium theories. The pre-medium theories lack a cohesive and explicit line of discourses in defining media. The medium theories explicitly addressed the issue of media and introduced a new line of scholarship informed by various disciplines during the emergence of the ‘mass media.’ The post-medium theories encompass a larger spectrum of scholarship addressing the issue of mediality in globalised and networked societies. Media typologies are usually based on media technologies or instruments of practices. In the current book, the broad media taxonomies are contextualised on the basis of mediation spheres, the holistic definition of medium discussed earlier. This categorisation provides the scope for analysing dynamics of media situations in a holistic way. The milestones of media transformations in history can be divided into six categories including, presentational, representational, mechanical, electronic, intelligent and biological mediation spheres. In chapter five the dynamics and characteristics of these mediation sphere are further discussed. Contemporary media practices, which are usually termed by the practitioners, can be broadly divided into two categories of media-design (e.g. software design, application design, information design, web design, game design, sound design, computer graphic design, vision-design, interface design, etc.) and media-art (e.g. app-art, application art/software art, game-art, sonic art, digital art, algorithm art, bio-art, neuro-art, interactive-art, video-art, etc.). The two fields of practices are conceptually indistinguishable and complementary to the larger contemporary media culture. The media arts practices are usually the innovative open fields, avant-garde practices or critical reflection on media culture. Media design practices are influenced by the mainstream productions, media literacy, media competence and communication traditions within a given media culture. The media usages and media literacies are expanding progressively depending on the context of media culture. In chapter six, a case study of app-art practices and critique of app culture are discussed in the framework of the intelligent mediation sphere

    Semantic Selection of Internet Sources through SWRL Enabled OWL Ontologies

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    This research examines the problem of Information Overload (IO) and give an overview of various attempts to resolve it. Furthermore, argue that instead of fighting IO, it is advisable to start learning how to live with it. It is unlikely that in modern information age, where users are producer and consumer of information, the amount of data and information generated would decrease. Furthermore, when managing IO, users are confined to the algorithms and policies of commercial Search Engines and Recommender Systems (RSs), which create results that also add to IO. this research calls to initiate a change in thinking: this by giving greater power to users when addressing the relevance and accuracy of internet searches, which helps in IO. However powerful search engines are, they do not process enough semantics in the moment when search queries are formulated. This research proposes a semantic selection of internet sources, through SWRL enabled OWL ontologies. the research focuses on SWT and its Stack because they (a)secure the semantic interpretation of the environments where internet searches take place and (b) guarantee reasoning that results in the selection of suitable internet sources in a particular moment of internet searches. Therefore, it is important to model the behaviour of users through OWL concepts and reason upon them in order to address IO when searching the internet. Thus, user behaviour is itemized through user preferences, perceptions and expectations from internet searches. The proposed approach in this research is a Software Engineering (SE) solution which provides computations based on the semantics of the environment stored in the ontological model
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