Methods: We address these issues by transforming the TCGA data into the Semantic Web standard Resource Description Format (RDF), link it to relevant datasets in the Linked Open Data (LOD) cloud and further propose an efficient data distribution strategy to host the resulting 20.4 billion triples data via several SPARQL endpoints. Having the TCGA data distributed across multiple SPARQL endpoints, we enable biomedical scientists to query and retrieve information from these SPARQL endpoints by proposing a TCGA tailored federated SPARQL query processing engine named TopFed. Results: We compare TopFed with a well established federation engine FedX in terms of source selection and query execution time by using 10 different federated SPARQL queries with varying requirements. Our evaluation results show that TopFed selects on average less than half of the sources (with 100% recall) with query execution time equal to one third to that of FedX. Conclusion: With TopFed, we aim to offer biomedical scientists a single-point-of-access through which distributed TCGA data can be accessed in unison. We believe the proposed system can greatly help researchers in the biomedical domain to carry out their research effectively with TCGA as the amount and diversity of data exceeds the ability of local resources to handle its retrieval and parsing.

Methods: We address these issues by transforming the TCGA data into the Semantic Web standard Resource Description Format (RDF), link it to relevant datasets in the Linked Open Data (LOD) cloud and further propose an efficient data distribution strategy to host the resulting 20.4 billion triples data via several SPARQL endpoints. Having the TCGA data distributed across multiple SPARQL endpoints, we enable biomedical scientists to query and retrieve information from these SPARQL endpoints by proposing a TCGA tailored federated SPARQL query processing engine named TopFed. Results: We compare TopFed with a well established federation engine FedX in terms of source selection and query execution time by using 10 different federated SPARQL queries with varying requirements. Our evaluation results show that TopFed selects on average less than half of the sources (with 100% recall) with query execution time equal to one third to that of FedX. Conclusion: With TopFed, we aim to offer biomedical scientists a single-point-of-access through which distributed TCGA data can be accessed in unison. We believe the proposed system can greatly help researchers in the biomedical domain to carry out their research effectively with TCGA as the amount and diversity of data exceeds the ability of local resources to handle its retrieval and parsing.

This study shows that a concurrent active noise control strategy for engine harmonics and road noise has a complementary effect. In particular, we found that engine booming noise is additionally attenuated when road noise control is concurrently used with engine harmonics control; an additional attenuation of 2.08 dB and 1.25 dB for the C1.5 and C2.0 orders, respectively, was achieved. A parallel multichannel feedforward controller for non-stationary narrowband engine harmonics and broadband road noise was designed and implemented to reduce noise in all four seats. Two control signals were considered independent because the reference signals, engine revolution speed for the engine harmonic controller, and acceleration signal for the road noise controller are uncorrelated. However, if the reference sensor for the road noise controller is installed along the overlapping transfer path between the engine noise and road noise, the engine noise may also be suppressed by the control signal for the road noise attenuation. Based on transfer path analyses for both engine harmonics and road noise, the optimal positions for the reference sensors were selected. In addition, we identified several overlapping transfer paths between the engine booming noise and road noise. A practical active noise control system combined with a remote microphone technique was implemented for a large six-cylinder sedan using a vehicle audio system to evaluate the noise attenuation performance. The experiments showed that the interior noise from the engine and road excitation was effectively suppressed by the proposed concurrent control strategy..