Laszlo Kovacs - Profile on Academia.edu (original) (raw)

Papers by Laszlo Kovacs

Magyar tudomány, Jul 1, 2023

Az irasos emlekek megőrzese a jovő szamara egy fontos feladata korunknak. A ma keszulő művek jele... more Az irasos emlekek megőrzese a jovő szamara egy fontos feladata korunknak. A ma keszulő művek jelentős resze mar digitalis formaban is tarolasra kerul, ugyanakkor fontos, hogy a regebben, csak nyomtatasban megjelent konyvekhez, irott anyagokhoz is hozzaferest biztositsunk korunk digitalis nemzedekenek. Az igy előallt adatbazis azonban hasznalhatatlan a tarolt anyagokban tortenő kereshetőseg megteremtese nelkul. Az MTA SZTAKI Elosztott Rendszerek Osztalya egy GVOP palyazat kereteben azt vizsgalta, hogy magyar nyelvű szkennelt szovegekben milyen hibak keletkeznek az eredeti dokumentumhoz kepest. Ezeket az eredmenyeket felhasznalva egy olyan kereső prototipusat epitettuk meg, amely egy digitalizalasbol eredő hibakat tartalmazo adatbazisban is megbizhatoan tud keresni.

Lecture Notes in Computer Science, 2005

A distributed digital library has been designed and implemented for the support of community radi... more A distributed digital library has been designed and implemented for the support of community radios. This framework, developed by the StreamOn-TheFly IST project of the EU, provides a common background for preparation, archival, exchange and reuse of radio programs and supports radio personalization. The architecture is based on a decentralized network of software components using automatic metadata replication in a peer-to-peer manner. This approach combines the principles and practice of OAI (Open Archives Initiative) with the peer-to-peer networking paradigm, and extends usual content dissemination with the aggregation of use statistics and user feedback. The network also promotes social self-organization of the community and a new common metadata schema and content exchange format.

The paper gives an overview about the ongoing INFRAWEBS project and describes the main modules an... more The paper gives an overview about the ongoing INFRAWEBS project and describes the main modules and software components embedded in an application oriented realisation framework. With regard to the SWS technology the inherently given message and position of this paper is to leave the conceptional level towards practical and reasonable applicable software tools and components.

One of the most important issues for Service Providers in Cloud Computing is delivering a good qu... more One of the most important issues for Service Providers in Cloud Computing is delivering a good quality of service. This is achieved by means of the adaptation to a changing environment where different failures can occur during the execution of different services and tasks. Some of these failures can be predicted taking into account the information obtained from previous executions. The results of these predictions will help the schedulers to improve the allocation of resources to the different tasks. In this paper, we present a framework which uses semantically enhanced historical data for predicting the behavior of tasks and resources in the system, and allocating the resources according to these predictions.

Communications in Nonlinear Science and Numerical Simulation, 2011

The under-actuated systems have less control inputs than degrees of freedom. We assume that the i... more The under-actuated systems have less control inputs than degrees of freedom. We assume that the investigated under-actuated systems have desired outputs of the same number as inputs. In spite of the fact that the inverse dynamical calculation leads to the solution of a system of differential algebraic equations (DAE), the desired control inputs can be determined uniquely by the method of computed torques. We often use natural (Cartesian) coordinates to describe the configuration of the robot, while a set of algebraic equations represents the geometric constraints. In this modeling approach the mathematical model of the dynamical system itself is also a DAE. The method of computed torque control with a PD controller is applied to underactuated systems described by natural coordinates. The inverse dynamics is solved via the backward Euler discretization of the DAE system for which a general formalism is proposed. Some results are presented in the form of a case study for a cart-pole system and confirmed by numerical simulation.

Evaluation of digital libraries assesses their effectiveness, quality and overall impact. To faci... more Evaluation of digital libraries assesses their effectiveness, quality and overall impact. To facilitate the comparison of different evaluations and to support the re-use of evaluation data, we are proposing a new logging schema. This schema will allow for logging and sharing of a wide array of data about users, systems and their interactions. We discuss the multi-level logging framework presented in [19] and describe how the community can add to and gain from using the framework. The main focus of this paper is the logging of events within digital libraries on a generalised, conceptual level, as well as the services based on it. These services will allow diverse digital libraries to store their log data in a common repository using a common format. In addition they provide means for analysis and comparison of search history data.

Cooperative and interoperability aspects of distributed digital document libraries are discussed.... more Cooperative and interoperability aspects of distributed digital document libraries are discussed. The commitment of ERCIM institutions to the Dienst protocol raised the necessity of the development of general detailed architecture of Dienst. A new Dienst architecture augmented by replication service is suggested. Replication is described in details. An abstract Reference Model of distributed digital document libraries can be concluded as well.

Digital libraries store documents in different ways, and provide various indexing and searching c... more Digital libraries store documents in different ways, and provide various indexing and searching capabilities. At this moment no uniform and/or standardized data, and catalog record formats are used. Although there are several initiatives for standardization of e.g. catalog record formats [6] there is no initiative for creating a standardized Reference Model of Distributed Digital Libraries. In this paper a set of digital libraries cooperating to provide uniform user services and digital data is presumed.

Mirroring (creation of remote copy) of WWW hypermedia documents is discussed. First a Portable Hy... more Mirroring (creation of remote copy) of WWW hypermedia documents is discussed. First a Portable Hypermedia Document (PHM) format is defined. Mirroring service and a software environment for mirroring are introduced. Mirroring environment automatizes the process of mirroring and transforms WWW hypermedia documents into PHM format. The algorithm and the architecture of the environment of mirroring service are described in detail.

The paper gives an overview about the ongoing FP6-IST INFRAWEBS project and describes the main la... more The paper gives an overview about the ongoing FP6-IST INFRAWEBS project and describes the main layers and software components embedded in an application oriented realisation framework. An important part of INFRAWEBS is a Semantic Web Unit (SWU) – a collaboration platform and interoperable middleware for ontology-based handling and maintaining of SWS. The framework provides knowledge about a specific domain and relies on ontologies to structure and exchange this knowledge to semantic service development modules. INFRAWEBS Designer and Composer are sub-modules of SWU responsible for creating Semantic Web Services using Case-Based Reasoning approach. The Service Access Middleware (SAM) is responsible for building up the communication channels between users and various other modules. It serves as a generic middleware for deployment of Semantic Web Services. This software toolset provides a development framework for creating and maintaining the full-life-cycle of Semantic Web Services wi...

Self-Organizing Distributed Digital Library Supporting Audio-Video

A Tolmácskesztyű projektben egy olyan segédeszközt alkotunk, mellyel a beszéd-és halláskárosult e... more A Tolmácskesztyű projektben egy olyan segédeszközt alkotunk, mellyel a beszéd-és halláskárosult emberek kézmozgását, vagyis gesztusokat használva képesek a mindennapi életben kapcsolatot teremteni ép embertársaikkal. A kifejlesztett segédeszköz egy innovatív hardver-szoftver-rendszer, amely kézmozgást érzékelő kesztyűből valamint kézjeleket felismerő és nyelvi feldolgozást végző szoftverből áll. A Tolmácskesztyű eszközrendszer jelnyelvi szinkrontolmácsként működik, segítségével a fogyatékkal élők anyanyelvükön-vagyis jelnyelven-kommunikálhatnak az épekkel. A Tolmácskesztyű applikáció a jelelt szöveget hangosan felolvassa, így a sérültek és a (jelnyelvet nem ismerő) épek között folytonos kommunikáció jön létre.

Distributed Archive and Web Services for Radio Stations

Www, 2003

DRM megoldások áttekintése

Current practice and shortcomings of handling digital hypermedia documents on the Internet are in... more Current practice and shortcomings of handling digital hypermedia documents on the Internet are investigated. The WebPack format is dened to eliminate some of these shortcomings. The structure and operations of this new container format are discussed, and the use of WebPack in document management is explained.

Life-Cycle Support of Semantic Web Services

Ercim, 2007