The Experts below are selected from a list of 180 Experts worldwide ranked by ideXlab platform

Robert L Olesen - One of the best experts on this subject based on the ideXlab platform.

  • dft spread ofdm with frequency Domain Reference symbols
    Global Communications Conference, 2017
    Co-Authors: Alphan Sahin, Erdem Bala, Rui Yang, Robert L Olesen
    Abstract:

    The fifth generation (5G) wireless standard will support several new use cases and 10 to 100 times the performance of fourth generation (4G) systems. Because of the diverse applications for 5G, flexible solutions which can address conflicting requirements will be needed. In this paper, we propose a solution which enables the use of discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) and OFDM, which address different requirements, using a common low-complexity Reference symbol (RS) design. In this solution, the DFT-s-OFDM symbol contains RSs in the frequency Domain that may be shared by a subsequent OFDM symbol. The proposed scheme is generated by puncturing the output of a DFT-spread block and replacing the punctured samples with RSs in frequency. We prove that puncturing the interleaved samples at the output of the DFT-spread operation equivalently introduces a periodic interference to the data symbols at the input of the DFT-spread operation. We show that the interference due to the puncturing can be removed with a low-complexity receiver by exploiting the zeros inserted to certain locations before the DFT-spread block at the transmitter. Simulation results support that the proposed scheme removes the error floor caused by the puncturing and achieves lower peak-to- average-power ratio than OFDM.

  • GLOBECOM - DFT-Spread OFDM with Frequency Domain Reference Symbols
    GLOBECOM 2017 - 2017 IEEE Global Communications Conference, 2017
    Co-Authors: Alphan Sahin, Erdem Bala, Rui Yang, Robert L Olesen
    Abstract:

    The fifth generation (5G) wireless standard will support several new use cases and 10 to 100 times the performance of fourth generation (4G) systems. Because of the diverse applications for 5G, flexible solutions which can address conflicting requirements will be needed. In this paper, we propose a solution which enables the use of discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) and OFDM, which address different requirements, using a common low-complexity Reference symbol (RS) design. In this solution, the DFT-s-OFDM symbol contains RSs in the frequency Domain that may be shared by a subsequent OFDM symbol. The proposed scheme is generated by puncturing the output of a DFT-spread block and replacing the punctured samples with RSs in frequency. We prove that puncturing the interleaved samples at the output of the DFT-spread operation equivalently introduces a periodic interference to the data symbols at the input of the DFT-spread operation. We show that the interference due to the puncturing can be removed with a low-complexity receiver by exploiting the zeros inserted to certain locations before the DFT-spread block at the transmitter. Simulation results support that the proposed scheme removes the error floor caused by the puncturing and achieves lower peak-to- average-power ratio than OFDM.

  • DFT-Spread OFDM with Frequency Domain Reference Symbols
    arXiv: Information Theory, 2017
    Co-Authors: Alphan Sahin, Erdem Bala, Rui Yang, Robert L Olesen
    Abstract:

    The fifth generation (5G) wireless standard will support several new use cases and 10 to 100 times the performance of fourth generation (4G) systems. Because of the diverse applications for 5G, flexible solutions which can address conflicting requirements will be needed. In this paper, we propose a solution which enables the use of discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) and OFDM, which address different requirements, using a common Reference symbol (RS) design. In this solution, the DFT-s-OFDM symbol contains RSs in the frequency Domain that may be shared by a subsequent OFDM symbol. The proposed scheme is generated by puncturing the output of a DFT-spread block and replacing the punctured samples with RSs in frequency. We prove that puncturing the interleaved samples at the output of the DFT-spread operation equivalently introduces a periodic interference to the data symbols at the input of the DFT-spread operation. We show that the interference due to the puncturing can be removed with a low-complexity receiver by exploiting the zeros inserted to certain locations before the DFT-spread block at the transmitter. Simulation results support that the proposed scheme removes the error floor caused by the puncturing and achieves lower peak-to-average-power ratio than OFDM.

Anita Burgun - One of the best experts on this subject based on the ideXlab platform.

  • desiderata for Domain Reference ontologies in biomedicine
    Journal of Biomedical Informatics, 2006
    Co-Authors: Anita Burgun
    Abstract:

    Domain Reference ontologies represent knowledge about a particular part of the world in a way that is independent from specific objectives, through a theory of the Domain. An example of Reference ontology in biomedical informatics is the Foundational Model of Anatomy (FMA), an ontology of anatomy that covers the entire range of macroscopic, microscopic, and subcellular anatomy. The purpose of this paper is to explore how two Domain Reference ontologies--the FMA and the Chemical Entities of Biological Interest (ChEBI) ontology, can be used (i) to align existing terminologies, (ii) to infer new knowledge in ontologies of more complex entities, and (iii) to manage and help reasoning about individual data. We analyze those kinds of usages of these two Domain Reference ontologies and suggest desiderata for Reference ontologies in biomedicine. While a number of groups and communities have investigated general requirements for ontology design and desiderata for controlled medical vocabularies, we are focusing on application purposes. We suggest five desirable characteristics for Reference ontologies: good lexical coverage, good coverage in terms of relations, compatibility with standards, modularity, and ability to represent variation in reality.

Xi Chen - One of the best experts on this subject based on the ideXlab platform.

  • IFSA/NAFIPS - Semantic similarity measures in ontology alignment
    2013 Joint IFSA World Congress and NAFIPS Annual Meeting (IFSA NAFIPS), 2013
    Co-Authors: Valerie Cross, Punam Silwal, Xi Chen
    Abstract:

    Numerous ontological or semantic similarity measures have been proposed to determine how similar one concept is to another within the context of an ontology. These measures are shown to have as their basis fuzzy set compatibility measures and have been used in a variety of biomedical and bioinformatics applications. In this paper a new matcher, the mediating matcher with semantic similarity (MMSS), has been designed in an adaptable manner and added to an existing OA system. Experiments are performed to compare the performance of several semantic similarity measures with different Domain Reference ontologies when used in the task of ontology alignment.

  • Semantic Similarity Measures in Ontology Alignment
    PROCEEDINGS OF THE 2013 JOINT IFSA WORLD CONGRESS AND NAFIPS ANNUAL MEETING (IFSA NAFIPS), 2013
    Co-Authors: V V Cross, Punam Silwal, Xi Chen
    Abstract:

    Numerous ontological or semantic similarity measures have been proposed\nto determine how similar one concept is to another within the context of\nan ontology. These measures are shown to have as their basis fuzzy set\ncompatibility measures and have been used in a variety of biomedical and\nbioinformatics applications. In this paper a new matcher, the mediating\nmatcher with semantic similarity (MMSS), has been designed in an\nadaptable manner and added to an existing OA system. Experiments are\nperformed to compare the performance of several semantic similarity\nmeasures with different Domain Reference ontologies when used in the\ntask of ontology alignment.

Eila Ovaska - One of the best experts on this subject based on the ideXlab platform.

  • ECSA Companion Volume - Analysis of a cross-Domain Reference architecture using change scenarios
    Proceedings of the 5th European Conference on Software Architecture - ECSA '11, 2011
    Co-Authors: Liliana Dobrica, Eila Ovaska
    Abstract:

    The content of this paper addresses the issue of how to perform analysis of a cross Domain Reference architecture. The cross Domain Reference architecture is designed based on the Domains requirements and features modeling. The definition of a cross Domain Reference architecture is based on well known concepts from software architecture description, service orientation and product line. We apply a method based on change scenarios to analyze variability at the architectural level. In order to handle complexity in analysis we propose categories of change scenarios to be derived from each problem Domain and we provide informal guidelines for each step of the analysis method.

  • ENASE (Selected Papers) - Service Based Development of a Cross Domain Reference Architecture
    Communications in Computer and Information Science, 2009
    Co-Authors: Liliana Dobrica, Eila Ovaska
    Abstract:

    An important trend of software engineering is that systems are in transition from component based architectures towards service centric ones. However, software product line engineering techniques can help in a quality based and systematic reuse. The content of this paper addresses the issue of how to perform design and quality analysis of cross Domain Reference architecture. The Reference architecture is designed based on the Domains requirements and features modelling. We propose a service based approach for cross-Domain Reference architecture development. Throughout the sections we try to introduce an innovative way of thinking founded on bridging concepts from software architecture, service orientation, software product lines, and quality analysis with the purpose to initiate and evolve software systems.

Alphan Sahin - One of the best experts on this subject based on the ideXlab platform.

  • dft spread ofdm with frequency Domain Reference symbols
    Global Communications Conference, 2017
    Co-Authors: Alphan Sahin, Erdem Bala, Rui Yang, Robert L Olesen
    Abstract:

    The fifth generation (5G) wireless standard will support several new use cases and 10 to 100 times the performance of fourth generation (4G) systems. Because of the diverse applications for 5G, flexible solutions which can address conflicting requirements will be needed. In this paper, we propose a solution which enables the use of discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) and OFDM, which address different requirements, using a common low-complexity Reference symbol (RS) design. In this solution, the DFT-s-OFDM symbol contains RSs in the frequency Domain that may be shared by a subsequent OFDM symbol. The proposed scheme is generated by puncturing the output of a DFT-spread block and replacing the punctured samples with RSs in frequency. We prove that puncturing the interleaved samples at the output of the DFT-spread operation equivalently introduces a periodic interference to the data symbols at the input of the DFT-spread operation. We show that the interference due to the puncturing can be removed with a low-complexity receiver by exploiting the zeros inserted to certain locations before the DFT-spread block at the transmitter. Simulation results support that the proposed scheme removes the error floor caused by the puncturing and achieves lower peak-to- average-power ratio than OFDM.

  • GLOBECOM - DFT-Spread OFDM with Frequency Domain Reference Symbols
    GLOBECOM 2017 - 2017 IEEE Global Communications Conference, 2017
    Co-Authors: Alphan Sahin, Erdem Bala, Rui Yang, Robert L Olesen
    Abstract:

    The fifth generation (5G) wireless standard will support several new use cases and 10 to 100 times the performance of fourth generation (4G) systems. Because of the diverse applications for 5G, flexible solutions which can address conflicting requirements will be needed. In this paper, we propose a solution which enables the use of discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) and OFDM, which address different requirements, using a common low-complexity Reference symbol (RS) design. In this solution, the DFT-s-OFDM symbol contains RSs in the frequency Domain that may be shared by a subsequent OFDM symbol. The proposed scheme is generated by puncturing the output of a DFT-spread block and replacing the punctured samples with RSs in frequency. We prove that puncturing the interleaved samples at the output of the DFT-spread operation equivalently introduces a periodic interference to the data symbols at the input of the DFT-spread operation. We show that the interference due to the puncturing can be removed with a low-complexity receiver by exploiting the zeros inserted to certain locations before the DFT-spread block at the transmitter. Simulation results support that the proposed scheme removes the error floor caused by the puncturing and achieves lower peak-to- average-power ratio than OFDM.

  • DFT-Spread OFDM with Frequency Domain Reference Symbols
    arXiv: Information Theory, 2017
    Co-Authors: Alphan Sahin, Erdem Bala, Rui Yang, Robert L Olesen
    Abstract:

    The fifth generation (5G) wireless standard will support several new use cases and 10 to 100 times the performance of fourth generation (4G) systems. Because of the diverse applications for 5G, flexible solutions which can address conflicting requirements will be needed. In this paper, we propose a solution which enables the use of discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) and OFDM, which address different requirements, using a common Reference symbol (RS) design. In this solution, the DFT-s-OFDM symbol contains RSs in the frequency Domain that may be shared by a subsequent OFDM symbol. The proposed scheme is generated by puncturing the output of a DFT-spread block and replacing the punctured samples with RSs in frequency. We prove that puncturing the interleaved samples at the output of the DFT-spread operation equivalently introduces a periodic interference to the data symbols at the input of the DFT-spread operation. We show that the interference due to the puncturing can be removed with a low-complexity receiver by exploiting the zeros inserted to certain locations before the DFT-spread block at the transmitter. Simulation results support that the proposed scheme removes the error floor caused by the puncturing and achieves lower peak-to-average-power ratio than OFDM.