There is enormous potential and interest in renewable energy generation from marine tidal currents. Tidal currents have been recognized as a valuable resource for the sustainable generation of electrical power. Tidal ...There is enormous potential and interest in renewable energy generation from marine tidal currents. Tidal currents have been recognized as a valuable resource for the sustainable generation of electrical power. Tidal currents are particularly attractive for power generation and advantageous when compared to other renewable energies due to their high predictability and fluid properties. The inlet between Ocean City, Maryland and Assateague Island has highly predictable tides and may have potential as a resource for renewable energy generation. In this paper, measurements of the tidal current velocity are made at various locations within the inlet. Measurements are made near the surface due to the energy flux of tidal channels being higher near the surface. The data show that the inlet is a potential candidate for deployment of vertical axis tidal turbines for small-scale renewable energy generation.展开更多
A set of dolphin echolocation signals previously collected from an Atlantic bottlenose dolphin in Kaneohe Bay, Hawai’i are decomposed using a matching pursuit algorithm to further investigate the role of four types o...A set of dolphin echolocation signals previously collected from an Atlantic bottlenose dolphin in Kaneohe Bay, Hawai’i are decomposed using a matching pursuit algorithm to further investigate the role of four types of echolocation signals outlined elsewhere [1]. The method decomposes the echolocation signals into optimal linear expansions of waveforms, which are Gabor functions defined in a dictionary. The method allows for study of the changes in frequency content within a dolphin’s functional bandwidth during discrimination tasks. We investigate the role of the functional bandwidth in terms of the signal energy levels and echolocations task performance. Furthermore, ROC analysis is applied to the relative energies of the matched waveforms to determine probability of discrimination. The results suggest that dolphins may discriminate by inspection of the relevant frequency differences between targets. In addition, the results from the ROC analysis provides insight into the role of the different classes of dolphin signals and of the importance of modification of the outgoing echolocation clicks, which may be fundamental to a dolphin’s ability to identify and discriminate targets.展开更多
文摘There is enormous potential and interest in renewable energy generation from marine tidal currents. Tidal currents have been recognized as a valuable resource for the sustainable generation of electrical power. Tidal currents are particularly attractive for power generation and advantageous when compared to other renewable energies due to their high predictability and fluid properties. The inlet between Ocean City, Maryland and Assateague Island has highly predictable tides and may have potential as a resource for renewable energy generation. In this paper, measurements of the tidal current velocity are made at various locations within the inlet. Measurements are made near the surface due to the energy flux of tidal channels being higher near the surface. The data show that the inlet is a potential candidate for deployment of vertical axis tidal turbines for small-scale renewable energy generation.
文摘A set of dolphin echolocation signals previously collected from an Atlantic bottlenose dolphin in Kaneohe Bay, Hawai’i are decomposed using a matching pursuit algorithm to further investigate the role of four types of echolocation signals outlined elsewhere [1]. The method decomposes the echolocation signals into optimal linear expansions of waveforms, which are Gabor functions defined in a dictionary. The method allows for study of the changes in frequency content within a dolphin’s functional bandwidth during discrimination tasks. We investigate the role of the functional bandwidth in terms of the signal energy levels and echolocations task performance. Furthermore, ROC analysis is applied to the relative energies of the matched waveforms to determine probability of discrimination. The results suggest that dolphins may discriminate by inspection of the relevant frequency differences between targets. In addition, the results from the ROC analysis provides insight into the role of the different classes of dolphin signals and of the importance of modification of the outgoing echolocation clicks, which may be fundamental to a dolphin’s ability to identify and discriminate targets.
