Search results for: call processing
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Call processing performance in multidomain IMS/NGN architecture
PublicationThe Next Generation Network (NGN) architecture, which bases on the IP Multimedia Subsystem (IMS) concept, is a proposition of a telecommunication network dedicated to the needs of the modern information society. The main goal of NGN is to provide Quality of Service (QoS), for which proper network design and dimensioning are necessary. This also requires appropriate traffic models, which should be efficient and not excessively complicated...
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Simulation model of IMS/NGN call processing performance
PublicationIn current telecommunications it is assumed that demands of the information society for quickly delivered services will be satisfied by the Next Generation Network (NGN) architecture, which includes IP Multimedia Subsystem (IMS) elements. To guarantee Quality of Service (QoS), proper design and dimensioning of NGN is absolutely necessary, for which appropriate models have to be proposed. As the NGN architecture is very complicated,...
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Call Processing Performance in a Multidomain IMS/NGN with Asymmetric Traffic
PublicationIn this paper we continue our research using the previously proposed analytical traffic model of a multidomain Next Generation Network (NGN), which is standardized for delivering multimedia services based on the IP Multimedia Subsystem (IMS). The aim of the model is to assess mean Call Set-up Delay (CSD) and mean Call Disengagement Delay (CDD), which are standardized call processing performance parameters. The output variables...
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Simulation model for assessment of IMS-based NGN call processing performance
PublicationIn current telecommunications it is assumed that demands of information society for quickly delivered services will be satisfied by Next Generation Network (NGN) architecture, which includes IP Multimedia Subsystem (IMS) elements. To guarantee Quality of Service (QoS), proper design and dimensioning of NGN is absolutely necessary, for which appropriate models have to be proposed. As NGN architecture is very complicated, the most...
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Traffic model for evaluation of call processing performance parameters in IMS-based NGN
PublicationIn the modern world requirements for accurate and fast information distribution are becoming more and more important, which creates a strong necessity for appropriate telecommunication network architecture. Proposition of such an architecture is the Next Generation Network (NGN) concept, which in order to guarantee Quality of Service (QoS), should be correctly designed and dimensioned. For this reason proper traffic models must...
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Analysis of IMS/NGN call processing performance using phase-type distributions
PublicationThis work is a continuation of our research on the traffic model dedicated for design and analysis of the Next Generation Network (NGN), which is standardized for distribution of current and future multimedia services based on the IP Multimedia Subsystem (IMS). Our analytical and simulation models allow evaluation of mean Call Set-up Delay E(CSD) as well as mean Call Disengagement Delay E(CDD) in a single domain of IMS/NGN. Ensuring...
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Analysis of IMS/NGN Call Processing Performance Using Phase-Type Distributions Based on Experimental Histograms
PublicationThe paper describes our further research done with the proposed analytical and simulation traffic models of the Next Generation Network (NGN), which is standardized for delivering multimedia services with strict quality and includes elements of the IP Multimedia Subsystem (IMS). The aim of our models of a single IMS/NGN domain is to evaluate two standardized call processing performance parameters, which appropriate values are very...
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Analysis of IMS/NGN call processing performance using G/G/1 queuing systems approximations
PublicationThe paper concerns the Next Generation Network (NGN), which is standardized for distribution of multimedia services based on the IP Multimedia Subsystem (IMS). To guarantee quality, accurate traffic models of IMS/NGN should be proposed. In the paper we compare results obtained with our analytical and simulation model of a single IMS/NGN domain, where various queuing systems are used in the analytical model (M/G/1 and approximations...
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Design of a Multidomain IMS/NGN Service Stratum
PublicationThe paper continues our research concerning the Next Generation Network (NGN), which is standardized for delivering multimedia services with strict quality and includes elements of the IP Multimedia Subsystem (IMS). A design algorithm for a multidomain IMS/NGN service stratum is proposed, which calculates the necessary CSCF servers CPU message processing times and link bandwidths with respect to the given maximum values of mean...
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TRAFFIC MODEL OF A MULTIDOMAIN IMS/NGN
PublicationIn this paper we continue our research and present an analytical traffic model of a multidomain Next Generation Network (NGN), which is standardized for delivering multimedia services based on the IP Multimedia Subsystem (IMS). The model takes into account several service scenarios (including registration, intra- and inter-operator calls) and a large set of network parameters. Using the model mean Call Set-up Delay and mean Call...
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Verification of the Analytical Traffic Model of a Multidomain IMS/NGN Using the Simulation Model
PublicationIn this paper we verify the previously proposed analytical traffic model of a multidomain Next Generation Network (NGN), which is standardized for delivering multimedia services based on the IP Multimedia Subsystem (IMS). For this reason a proper simulation model used, in which not theoretical queuing system models but the operation of real network elements and standardized call scenarios are accurately implemented. Consequently,...
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Performance Models of a Multidomain IMS/NGN Service Stratum
PublicationThis paper quantifies call processing performance (CPP) of a multidomain IMS/NGN architecture, which was proposed to deliver current and future telecommunication services with strict quality requirements, independently of the transport network technologies. A realistic simulation model is used as a reference for evaluation of the analytical results, in which vari-ous types of queuing systems are applied to model the opera-tion...
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Analytical Traffic Model for a Multidomain IMS/NGN Network Including Service and Transport Stratum
PublicationThis paper addresses the problem of modelling call processing performance (CPP) in a multidomain Next Generation Network (NGN) architecture including the elements of the IP Multimedia Subsystem (IMS) in service stratum and based on the Multiprotocol Label Switching (MPLS) technology in transport stratum. An analytical traffic model for such an architecture is proposed by integrating the formerly implemented submodels of service...
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Quality Parameters in IMS/NGN Networks
PublicationThe Next Generation Network (NGN) architecture, including elements of the IP Multimedia Subsystem (IMS) concept, is a proposition of a telecommunication network dedicated to the needs of current and future information society. The main goal of NGN is to provide Quality of Service (QoS), for which proper network design is necessary with respect to among others standardized call processing performance parameters, including expected...
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Performance Evaluation of a Multidomain IMS/NGN Network Including Service and Transport Stratum
PublicationThe Next Generation Network (NGN) architecture was proposed for delivering various multimedia services with guaranteed quality. For this reason, the elements of the IP Multimedia Subsystem (IMS) concept (an important part of 4G/5G/6G mobile networks) are used in its service stratum. This paper presents comprehensive research on how the parameters of an IMS/NGN network and traffic sources influence mean Call Set-up Delay (E(CSD))...
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Introduction to the special issue on machine learning in acoustics
PublicationWhen we started our Call for Papers for a Special Issue on “Machine Learning in Acoustics” in the Journal of the Acoustical Society of America, our ambition was to invite papers in which machine learning was applied to all acoustics areas. They were listed, but not limited to, as follows: • Music and synthesis analysis • Music sentiment analysis • Music perception • Intelligent music recognition • Musical source separation • Singing...
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A memory efficient and fast sparse matrix vector product on a Gpu
PublicationThis paper proposes a new sparse matrix storage format which allows an efficient implementation of a sparse matrix vector product on a Fermi Graphics Processing Unit (GPU). Unlike previous formats it has both low memory footprint and good throughput. The new format, which we call Sliced ELLR-T has been designed specifically for accelerating the iterative solution of a large sparse and complex-valued system of linear equations arising...
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Wydajność przetwarzania żądań usług uwarunkowanych czasowo realizowanych w sieci IMS/NGN
PublicationW rozprawie dokonano przeglądu stanu implementacji koncepcji IMS/NGN, a także modeli systemów obsługi z oczekiwaniem pod kątem zastosowania dla serwerów i łączy w modelu analitycznym wielodomenowej sieci IMS/NGN. Przedstawiono założenia dla tego modelu oraz metodologię obliczeń i analizy wyników: średnich czasów E(CSD) zestawiania i E(CDD) rozłączenia połączenia dla scenariuszy połączeń zakończonych sukcesem. Opisano założenia,...
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Evaluation of ASON/GMPLS Connection Control Servers Performance
PublicationPerformance aspects have always been very important in telecommunications, especially in control elements. That problem also regards ASON/GMLPS network, which is one of the propositions for Next Generation Network (NGN) transport stratum. In this paper we investigate performance of ASON/GMPLS Connection Control Servers (CCSs) in laboratory testbed, which architecture and operation are also described. In order to evaluate the performance...
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Call Control Evaluation in ASON/GMPLS Architecture
PublicationThe Automatically Switched Optical Network (ASON) utilizing Generalized Multi–Protocol Label Switching (GMPLS) protocols named as ASON/GMPLS is one of the propositions of Next Generation Network. The basic assumption of ASON control plane is a separation of call control from connection control. The control plane is divided into call control and connection control components. Presented work regards the problem of call control evaluation...
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The model of end-to-end call setup time calculation for Session Initiation Protocol
PublicationEnd-to-end call setup delay is one of the most important grade of service (GoS) parameters for VoIP networks with Session Initiation Protocol (SIP). A typical subscriber wants to have a connection established as soon as possible. From the operator's perspective call setup time is also crucial because he needs to know how probability of successful packet transmission on SIP links is related to a call setup delay. Then he can make...
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Global defensive secure structures
PublicationLet S ⊂ V (G) for a given simple non-empty graph G. We define for any nonempty subset X of S the predicate SECG,S(X) = true iff |NG[X]∩S| ≥ |NG[X]\S|. Let H be a non-empty family of graphs such that for each vertex v ∈ V (G) there is a subgraph H of G containing v and isomorphic to a member of H. We introduce the concept of H-alliance extending the concept of global defensive secure structures. By an H-alliance in a graph G we...
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Service time distribution influence on end-to-end call setup delay calculation in networks with Session Initiation Protocol
PublicationThe most important GoS parameter for networks with SIP protocol is end-to-end call setup delay. So far there were no coherent models allowing calculation of these parameters for networks with SIP protocol. Few models were developed but they are insufficient. In the paper we propose model which allows end-to-end call setup delay calculation for networks with SIP protocol. The model is using chain of M/G/1/K models and is applicable...
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REAL-TIME VOICE QUALITY MONITORING TOOL FOR VOIP OVER IPV6 NETWORKS
PublicationThe primary aim of this paper is to present a new application which is at this moment the only open source real-time VoIP quality monitoring tool that supports IPv6 networks. The application can keep VoIP system administrators provided at any time with up-to-date voice quality information. Multiple quality scores that are automatically obtained throughout each call reflect influence of variable packet losses and delays on voice...
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Call and Connections Times in ASON/GMPLS Architecture
PublicationIt is assumed that demands of information soci- ety could be satisfied by architecture ASON/GMPLS comprehended as Automatically Switched Optical Network (ASON) with Generalized Multi-Protocol Label Switching (GMPLS) protocols. Introduction this solution must be preceded by performance evaluation to guarantee society expectations. Call and connections times are in ASON/GMPLS architecture important for real-time applications. Practical...
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Simulation Model for Application of the SDN Concept in IMS/NGN Network Transport Stratum
PublicationThe paper presents a simulation model allowing examination of cooperation between two currently used telecommunication networks concepts: IP Multimedia Subsystem/Next Generation Network (IMS/NGN) and Software-Defined Networking (SDN). Application of the SDN architecture elements in IMS/NGN networks will enable unified control and management of transport resources for various transport technologies and equipment manufacturers. However,...
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Quality measure of VoIP services in carrier grade systems
PublicationThis paper describes passive measurement method of VoIP services quality in carrier grade systems, engaging slight system resources. Measurement is based on analyzing quality information in sender and receiver reports in RTCP packets sent by the end points of RTP session. Data is analyzed and stored by Session Boarder Controllers SBC. Objective evaluation of VoIP calls is based on quality information of IP connection and voice...
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Knowledge Management Challenges in Collaborative Design of a Virtual Call Centre
PublicationThis paper presents the analysis of knowledge management issues for an user interface consulting project relevant during the development of a Virtual Call Centre. Experiences gathered by the team of designers and team of usability consultants have been described and evaluated from the knowledge management viewpoint. A concept of a knowledge-based system, potentially supporting usability consulting in subsequent IT projects has...
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Bio-inspired Urban Design: Smart Growth and Sustainable Development Frameworks for a New Urban Unit in Cracow
PublicationIn March 2012, architects João Diniz (Brazil) and Dorota Wiśniewska (Poland) answered a call to competition from the City of Cracow, submitting an entry for the redesign of 5600 ha of the Nowa Huta district in eastern Cracow, focusing on economic revitalization within a framework of smart growth and sustainable development. The scenario included an ArcerolMittal Steelworks and incorporated a strong ecological analysis for the easternmost...
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Nonstandard Equivalence Scales and their Applications for European Union Countries
PublicationThe aim of this study is twofold. First, we propose new methods of estimating equivalence scales. We call these methods nonstandard to distinguish them from the standard procedures based on the microeconomic theory of demand systems. Searching for the ‘as simple as possible’ method has been a leitmotiv of this study. Second, we estimate various forms of equivalence scales for 28 European Union (EU) member countries and four non-member...
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Towards hardware built-in support for computer system safety
PublicationArtykuł omawia dostępne technologie wirtualizacji zasobów pamięci i systemów I/O w systemach komputerowych takie jak Execute Disable Bit (EDB) capability i Virtual Machine Architecture (VMA). Nastepnie wprowadza założenia na rozszerzenie tych technologii w celu uzyskania funkcjonalności Safe Call Execution dzieki technologii Execution Disabling Policies (EDP). Wprowadzono również założenia na funkcjonalność Memory Virtualization...
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The (Un)Real City by Magdalena Abakanowicz: Guidelines for Cities in Times of Planetary Crisis
PublicationThree decades have passed since Magdalena Abakanowicz presented her concept of Bois de Nanterre — Arboreal Architecture, in response to a call for a broader reflection on approaches to urban landscaping and a reinterpretation of the meaning and evolution of the Grand Axis in Paris. This paper analyses the work presented by the artist from an urban planning perspective. It shows how the rich and multi-layered metaphor for the 21st-century...
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Computer-aided analysis of resonance risk in power system with Static Var Compensators
PublicationStatic Var Compensators operation in a power system may significantly improve voltage profiles in nodes and the reactive power balance, as well as ensure greater system stability in emergency conditions. However these devices may be a cause of a resonance in the system. The aim of this paper is to call attention to the need to include resonance phenomena in a compensator’s location evaluation process. The analysis performed in...
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Collective Uncertainty Entanglement Test
PublicationFor a given pure state of a composite quantum system we analyze the product of its projections onto aset of locally orthogonal separable pure states. We derive a bound for this product analogous to theentropic uncertainty relations. For bipartite systems the bound is saturated for maximally entangled statesand it allows us to construct a family of entanglement measures, we shall call collectibility. As thesequantities are experimentally...
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How Machine Learning Contributes to Solve Acoustical Problems
PublicationMachine learning is the process of learning functional relationships between measured signals (called percepts in the artificial intelligence literature) and some output of interest. In some cases, we wish to learn very specific relationships from signals such as identifying the language of a speaker (e.g. Zissman, 1996) which has direct applications such as in call center routing or performing a music information retrieval task...
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Simulator for Performance Evaluation of ASON/GMPLS Network
PublicationThe hierarchical control plane network architecture of Automatically Switched Optical Network with utilization of Generalized Multi-Protocol Label Switching protocols is compliant to next generation networks requirements and can supply connections with required quality of service, even with incomplete domain information. Considering connection control, connection management and network management, the controllers of this architecture...
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Rigorous numerics for critical orbits in the quadratic family
PublicationWe develop algorithms and techniques to compute rigorous bounds for finite pieces of orbits of the critical points, for intervals of parameter values, in the quadratic family of one-dimensional maps fa(x)=a−x2. We illustrate the effectiveness of our approach by constructing a dynamically defined partition P of the parameter interval Ω=[1.4,2] into almost 4 million subintervals, for each of which we compute to high precision the...
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Geo-location of the commune of an IP user
PublicationThis paper describes a system of geo-location of an IP user that would enable VoIP users to call 112. Basic requirement is fast (under 50ms) determination of the commune of the subscriber. To obtain as accurate information as possible aggregation of several methods was proposed: using a database of locations of IP ranges created by specialized companies, traceroute using history of user locations to assume his current one.It is...
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Peer assessment as a method for measuring harmful internet use
PublicationHarmful Internet use (HIU) describes unintended use of the Internet. It could be both self-harm and harming others. Our research goal is to develop a more accurate method for measuring HIU by this novel peer assessment. As such, it may become, with our call for more research, a paradigm shift supplementing every rating scale or other type of Internet use assessment. In addition to classic statistical analysis, structural equations...
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Usługi Third Party Call Control zrealizowane z wykorzystaniem oprogramowania Open Source
PublicationKoncepcja sieci NGN zakłada otwartość na usługi udostępniane użytkownikom (abonentom). Jej realizacja wymaga ulokowania tej funkcjonalności w zewnętrznych elementach w stosunku do sieci telekomunikacyjnej udostępniającej usługi przenoszenia. Jednym z rozwiązań jest serwer Third Party Call Control (3PCC) w którym można ulokować scenariusze sterowania przebiegiem połączenia. W artykule przedstawiono i omówiono projekt, wykonany w...
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Performance Evaluation of Control Plane Functions in ASON/GMPLS Architecture
PublicationIt is assumed that demands of information society could be satisfied by architecture ASON/GMPLS comprehended as Automatically Switched Optical Network (ASON) with Generalized Multi-Protocol Label Switching (GMPLS) protocols. Introduction this solution must be preceded performance evaluation to guarantee society expectations. Practical realization is expensive and simulations models are necessary to examine standardized propositions....
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Weak Solutions within the Gradient-Incomplete Strain-Gradient Elasticity
PublicationIn this paper we consider existence and uniqueness of the three-dimensional static boundary-value problems in the framework of so-called gradient-incomplete strain-gradient elasticity. We call the strain-gradient elasticity model gradient-incomplete such model where the considered strain energy density depends on displacements and only on some specific partial derivatives of displacements of first- and second-order. Such models...
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A Nonlinear Model of a Mesh Shell
PublicationFor a certain class of elastic lattice shells experiencing finite deformations, a continual model using the equations of the so-called six-parameter shell theory has been proposed. Within this model, the kinematics of the shell is described using six kinematically independent scalar degrees of freedom — the field of displacements and turns, as in the case of the Cosserat continuum, which gives reason to call the model under consideration...
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Design and Configuration of Context-aware VoIP Telephony Systems
PublicationVoice over IP is a widely used concept with regard to a realization technology of different types of telephony systems, including those that are used in enterprises. Such systems of a call procesing component and a set of desk endpoints that are pervasove from a user perspective. Those andpoints are usually not mobile, but in result can deliver a much greater set of functions needed in an everyday office work. Those functions also...
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Multiresolution analysis and adaptive estimation on a sphere using stereographic wavelets
PublicationWe construct an adaptive estimator of a density function on d dimensional unit sphere Sd (d ≥ 2), using a new type of spherical frames. The frames, or as we call them, stereografic wavelets are obtained by transforming a wavelet system, namely Daubechies, using some stereographic operators. We prove that our estimator achieves an optimal rate of convergence on some Besov type class of functions by adapting to unknown smoothness....
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Weak forms of shadowing in topological dynamics
PublicationWe consider continuous maps of compact metric spaces. It is proved that every pseudotrajectory with sufficiently small errors contains a subsequence of positive density that is point-wise close to a subsequence of an exact trajectory with the same indices. Also, we study homeomor- phisms such that any pseudotrajectory can be shadowed by a finite number of exact orbits. In terms of numerical methods this property (we call it multishadowing)...
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The Challenge of Quantification: An Interdisciplinary Reading
PublicationThe present work looks at what we call “the multiverse of quantification”, where visible and invisible numbers permeate all aspects and venues of life. We review the contributions of different authors who focus on the roles of quantification in society, with the aim of capturing different and sometimes separate voices. Several scholars, including economists, jurists, philosophers, sociologists, communication and data scientists,...
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Isolation Number versus Domination Number of Trees
PublicationIf G=(VG,EG) is a graph of order n, we call S⊆VG an isolating set if the graph induced by VG−NG[S] contains no edges. The minimum cardinality of an isolating set of G is called the isolation number of G, and it is denoted by ι(G). It is known that ι(G)≤n3 and the bound is sharp. A subset S⊆VG is called dominating in G if NG[S]=VG. The minimum cardinality of a dominating set of G is the domination number, and it is denoted by γ(G)....
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On minimum cost edge searching
PublicationWe consider the problem of finding edge search strategies of minimum cost. The cost of a search strategy is the sum of searchers used in the clearing steps of the search. One of the natural questions is whether it is possible to find a search strategy that minimizes both the cost and the number of searchers used to clear a given graph G. We call such a strategy ideal. We prove, by an example, that ideal search strategies do not...
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NLP Questions Answering Using DBpedia and YAGO
PublicationIn this paper, we present results of employing DBpedia and YAGO as lexical databases for answering questions formulated in the natural language. The proposed solution has been evaluated for answering class 1 and class 2 questions (out of 5 classes defined by Moldovan for TREC conference). Our method uses dependency trees generated from the user query. The trees are browsed for paths leading from the root of the tree to the question...