The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Beatrice Pesquetpopescu - One of the best experts on this subject based on the ideXlab platform.
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temporal scalability through adaptive m band filter banks for robust h 264 mpeg 4 avc video coding
EURASIP Journal on Advances in Signal Processing, 2006Co-Authors: Cyril Bergeron, Catherine Lamybergot, G Pau, Beatrice PesquetpopescuAbstract:This paper presents different structures that use adaptive M-band hierarchical filter banks for temporal scalability. Open-loop and closed-loop configurations are introduced and illustrated using existing video codecs. In particular, it is shown that the H.264/MPEG-4 AVC codec allows us to introduce scalability by frame shuffling operations, thus keeping Backward Compatibility with the standard. The large set of shuffling patterns introduced here can be exploited to adapt the encoding process to the video content features, as well as to the user equipment and transmission channel characteristics. Furthermore, simulation results show that this scalability is obtained with no degradation in terms of subjective and objective quality in error-free environments, while in error-prone channels the scalable versions provide increased robustness.
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adaptive m band hierarchical filterbank for compliant temporal scalability in h 264 standard
International Conference on Acoustics Speech and Signal Processing, 2005Co-Authors: Cyril Bergeron, Catherine Lamybergot, Beatrice PesquetpopescuAbstract:The paper presents a solution of temporal scalability for video encoded H.264/MPEG-4 AVC bitstreams. Achieved through the concept of adaptive M-band hierarchical filterbanks, the temporal scalability is performed thanks to the application of a frame shuffling operation which allows Backward Compatibility with the standard to be kept. Simulation results show that this scalability is obtained with no degradation in terms of subjective and objective quality.
Jorg Claussen - One of the best experts on this subject based on the ideXlab platform.
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generational transitions in platform markets the role of Backward Compatibility
Social Science Research Network, 2016Co-Authors: Jorg Claussen, Tobias KretschmerAbstract:The introduction of a new product generation forces incumbents in platform markets to rebuild their installed base of complementary products. Using three different datasets on the US market for video game consoles, we show that incumbents can to some extent substitute for rebuilding their new installed base by making their new products Backward compatible, which lets them draw on the installed base of software for the parent generation. However, while this positive direct effect of Backward Compatibility dominates in our setting, we also observe a (weaker) negative indirect effect working through the reduced supply of new software. We find that both effects are moderated by the age of the new technological generation and by the technological leap between generations: Backward Compatibility becomes less important with increasing console age and with larger technological improvement between generations.
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Backward Compatibility to sustain market dominance evidence from the us handheld video game industry
Research Papers in Economics, 2010Co-Authors: Jorg Claussen, Tobias Kretschmer, Thomas S SpenglerAbstract:The introduction of a new product generation forces incumbents in network industries to rebuild their installed base to maintain an advantage over potential entrants. We study if Backward Compatibility can help moderate this process of rebuilding an installed base. Using a structural model of the US market for handheld game consoles, we show that Backward Compatibility lets incumbents transfer network effects from the old generation to the new to some extent but that it also reduces supply of new software. We also find that Backward Compatibility matters most shortly after the introduction of a new generation. Finally, we examine the tradeoff between technological progress and Backward Compatibility and find that Backward Compatibility matters less if there is a large technological leap between two generations. We subsequently use our results to assess the role of Backward Compatibility as a strategy to sustain a dominant market position.
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market leadership through technology Backward Compatibility in the u s handheld video game industry
Research Papers in Economics, 2010Co-Authors: Jorg Claussen, Tobias Kretschmer, Thomas SpenglerAbstract:The introduction of a new product generation forces incumbents in network industries to rebuild their installed base to maintain an advantage over potential entrants. We study if Backward Compatibility moderates this process of rebuilding an installed base. Using a structural model of the U.S. market for handheld game consoles, we show that Backward Compatibility lets incumbents transfer network effects from the old generation to the new to some extent but that it also reduces supply of new software. We examine the tradeoff between technological progress and Backward Compatibility and find that Backward Compatibility matters less if there is a large technological leap between two generations. We subsequently use our results to assess the role of Backward Compatibility as a strategy to sustain market leadership.
Jeanluc Gala - One of the best experts on this subject based on the ideXlab platform.
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Backward Compatibility of whole genome sequencing data with mlva typing using a new mlvatype shiny application for vibrio cholerae
PLOS ONE, 2019Co-Authors: Jerome Ambroise, Leonid M Irenge, Jeanfrancois Durant, Bertrand Bearzatto, Godfrey Bwire, Colin O Stine, Jeanluc GalaAbstract:BACKGROUND Multiple-Locus Variable Number of Tandem Repeats (VNTR) Analysis (MLVA) is widely used by laboratory-based surveillance networks for subtyping pathogens causing foodborne and water-borne disease outbreaks. However, Whole Genome Sequencing (WGS) has recently emerged as the new more powerful reference for pathogen subtyping, making a data conversion method necessary which enables the users to compare the MLVA identified by either method. The MLVAType shiny application was designed to extract MLVA profiles of Vibrio cholerae isolates from WGS data while ensuring Backward Compatibility with traditional MLVA typing methods. METHODS To test and validate the MLVAType algorithm, WGS-derived MLVA profiles of nineteen Vibrio cholerae isolates from Democratic Republic of the Congo (n = 9) and Uganda (n = 10) were compared to MLVA profiles generated by an in silico PCR approach and Sanger sequencing, the latter being used as the reference method. RESULTS Results obtained by Sanger sequencing and MLVAType were totally concordant. However, the latter were affected by censored estimations whose percentage was inversely proportional to the k-mer parameter used during genome assembly. With a k-mer of 127, less than 15% estimation of V. cholerae VNTR was censored. Preventing censored estimation was only achievable when using a longer k-mer size (i.e. 175), which is not proposed in the SPAdes v.3.13.0 software. CONCLUSION As NGS read lengths and qualities tend to increase with time, one may expect the increase of k-mer size in a near future. Using MLVAType application with a longer k-mer size will then efficiently retrieve MLVA profiles from WGS data while avoiding censored estimation.
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Backward Compatibility of whole genome sequencing data with mlva typing using a new mlvatype shiny application the example of vibrio cholerae
bioRxiv, 2019Co-Authors: Jerome Ambroise, Leonid M Irenge, Jeanfrancois Durant, Bertrand Bearzatto, Godfrey Bwire, Colin O Stine, Jeanluc GalaAbstract:Abstract Multiple-Locus Variable Number of Tandem Repeats (VNTR) Analysis (MLVA) is widely used by laboratory-based surveillance networks for subtyping pathogens causing foodborne and water-borne disease outbreaks. However, Whole Genome Sequencing (WGS) has recently emerged as the new more powerful reference for pathogen subtyping, making a data conversion method necessary which enables the users to compare the MLVA identified by either method. The MLVAType shiny application was designed to extract MLVA profiles from WGS data while ensuring Backward Compatibility with traditional MLVA typing methods. To test and validate the MLVAType algorithm, WGS-derived MLVA profiles of nineteen Vibrio cholerae isolates from Democratic Republic of the Congo (n=9) and Uganda (n=10) were compared to MLVA profiles generated by microchip electrophoresis (Bioanalyzer Agilent 2100), GeneScan analysis, and Sanger sequencing as the reference method. Unlike amplicon-size derived MLVA profiles, results obtained by Sanger sequencing and WGS were totally concordant. However, the latter were affected by censored estimations whose percentage was inversely proportional to the k-mer parameter used during genome assembly. With a k-mer of 127, less than 15% estimation of V. cholerae VNTR was censored. Preventing censored estimation was only achievable when using a longer k-mer size (i.e. 175), which is not proposed in the SPAdes v.3.13.0 software. In silico analysis showed that this limitation does not apply to other microbial species (e.g. Mycobacterium, Streptococcus, Staphylococcus, and Pseudomonas) characterized by smaller lengths of motif repeats. As NGS read lengths and qualities tend to increase with time, one may expect the increase of k-mer size in a near future. Using MLVAType application with a longer k-mer size will then efficiently retrieve MLVA profiles from WGS data while avoiding censored estimation irrespective of the microbial species. Author summary Next Generation Sequencing (NGS) has emerged as a powerful high throughput genomic approach enabling the Whole Genome Sequence (WGS) of pathogens to be assembled in a relatively short time. A major advantage of WGS, compared to traditional genotypic identification and typing methods, is its ability to generate data that can be exploited in silico for multiple bacterial tests including accurate subtyping, determination of genetic relatedness, and characterization of virulence and antimicrobial resistance determinants. Accordingly, WGS is now rapidly replacing traditional methods like Multi-Locus Variable Number of Tandem Repeats Analysis (MLVA) that has long been used in the public health sector for laboratory-based surveillance of pathogens and outbreak response. While these missions require maintenance of data comparability within networks, the lack of Backward Compatibility between WGS-derived and traditional MLVA methods is a well-recognized issue. As illustrated here with Vibrio cholerae isolates from DRC and Uganda, the MLVAType software application analyzes WGS data to generate MLVA profiles that are identical to those determined with traditional typing. Interestingly, this tool has also the potential to extract MLVA profiles from any bacterial genome that are characterized by a small number of tandem repeats, e.g. Streptococcus, Staphylococcus, Pseudomonas, and Mycobacterium species. This restriction can be lifted if subsequences of length k, called k-mers, are longer than what is currently proposed by genome assembly algorithm like SPAdes v.3.13.0.
Paul Wielage - One of the best experts on this subject based on the ideXlab platform.
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An efficient on-chip NI offering guaranteed services, shared-memory abstraction, and flexible network configuration
IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems, 2005Co-Authors: Andrei Radulescu, Edwin Rijpkema, Paul Wielage, John Dielissen, Santiago González Pestana, Om P. Gangwal, Kees GoossensAbstract:We present a network interface (NI) for an on-chip network. Our NI decouples computation from communication by offering a shared-memory abstraction, which is independent of the network implementation. We use a transaction-based protocol to achieve Backward Compatibility with existing bus protocols such as AXI, OCP, and DTL. Our NI has a modular architecture, which allows flexible instantiation. It provides both guaranteed and best-effort services via connections. These are configured via NI ports using the network itself, instead of a separate control interconnect. An example instance of this NI with four ports has an area of 0.25 mm/sup 2/ after layout in 0.13-/spl mu/m technology, and runs at 500 MHz.
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an efficient on chip network interface offering guaranteed services shared memory abstraction and flexible network configuration
Design Automation and Test in Europe, 2004Co-Authors: Andrei Radulescu, Edwin Rijpkema, John Dielissen, Kees Goossens, Paul WielageAbstract:In this paper we present a network interface for an on-chip network. Our network interface decouples computation from communication by offering a shared-memory abstraction, which is independent of the network implementation. We use a transaction-based protocol to achieve Backward Compatibility with existing bus protocols such as AXI, OCP and DTL. Our network interface has a modular architecture, which allows flexible instantiation. It provides both guaranteed and best-effort services via connections. These are configured via network interface ports using the network itself, instead of a separate control interconnect. An example instance of this network interface with 4 ports has an area of 0.143 mm/sup 2/ in a 0.13 /spl mu/m technology, and runs at 500 MHz.
Cyril Bergeron - One of the best experts on this subject based on the ideXlab platform.
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temporal scalability through adaptive m band filter banks for robust h 264 mpeg 4 avc video coding
EURASIP Journal on Advances in Signal Processing, 2006Co-Authors: Cyril Bergeron, Catherine Lamybergot, G Pau, Beatrice PesquetpopescuAbstract:This paper presents different structures that use adaptive M-band hierarchical filter banks for temporal scalability. Open-loop and closed-loop configurations are introduced and illustrated using existing video codecs. In particular, it is shown that the H.264/MPEG-4 AVC codec allows us to introduce scalability by frame shuffling operations, thus keeping Backward Compatibility with the standard. The large set of shuffling patterns introduced here can be exploited to adapt the encoding process to the video content features, as well as to the user equipment and transmission channel characteristics. Furthermore, simulation results show that this scalability is obtained with no degradation in terms of subjective and objective quality in error-free environments, while in error-prone channels the scalable versions provide increased robustness.
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adaptive m band hierarchical filterbank for compliant temporal scalability in h 264 standard
International Conference on Acoustics Speech and Signal Processing, 2005Co-Authors: Cyril Bergeron, Catherine Lamybergot, Beatrice PesquetpopescuAbstract:The paper presents a solution of temporal scalability for video encoded H.264/MPEG-4 AVC bitstreams. Achieved through the concept of adaptive M-band hierarchical filterbanks, the temporal scalability is performed thanks to the application of a frame shuffling operation which allows Backward Compatibility with the standard to be kept. Simulation results show that this scalability is obtained with no degradation in terms of subjective and objective quality.
