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The availability of dissolved inorganic carbon (DIC) may have a considerable impact on species competition in phytoplankton communities. The growth, photosynthetic characteristics and competition of three strains, the toxic Microcystis aeruginosa FACHB 912, nontoxic M. aeruginosa FACHB 469 and Chlamydomonas microsphaera FACHB 52, were investigated under two different DIC concentrations (0.365 and 7.658 mmol l À1 KHCO 3 ). In monoculture, DIC concentration did not affect the specific growth rates of any of the three strains. However, when grown in mixed culture with C. microsphaera, both toxic and nontoxic Microcystis strains showed increased percentages under low DIC concentration but decreased percentages under high DIC concentration. After 12 days' mixed culture, the percentage of M. aeruginosa FACHB 912 or FACHB 469 decreased by 9À22% in high DIC medium, but increased by 6-11% in low DIC medium. Low DIC concentration decreased the cell size, cellular chlorophyll fluorescence and photosynthetic capacity of C. microsphaera, but it had little effect on those of M. aeruginosa FACHB 912 and FACHB 469. The apparent photosynthetic affinities for DIC were significantly higher in the two M. aeruginosa strains than in C. microsphaera. From the higher DIC affinity, more efficient photosynthetic capacity and increased percentages in competition experiments under low DIC concentration, it can be concluded that the bloom-forming M. aeruginosa possesses a competitive advantage in DIC-limited conditions.

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The lateral line is a critical mechanosensory organ that enables fish to perceive the surroundings accurately and rapidly. Massive efforts have been made to build an artificial lateral line system rivaling that of fish for underwater vehicles. Dipole source localization has become a standard problem for evaluating the sensing capabilities of the developed systems. In this paper we propose, for the first time, the multiple signal classification (MUSIC) method in order to achieve high-resolution dipole source localization based on spatial spectrum estimation. We also present the minimum variance distortionless response (MVDR) by making an improvement to the previous Capon's method. Experiments are conducted on a linear prototype of lateral line canal and the localization performance of these two methods are compared. The results show that the MUSIC method provides an overall localization resolution improvement of 10.4% and maintains a similar level of localization accuracy compared with the MVDR method. Further studies show that the MUSIC method has the potential of localizing two closer incoherent dipole sources with a minimum lateral separation of 20 mm, versus 70 mm for the MVDR method, at a dipole-array distance of half the array length. Both localization methods have strong robustness to the vibrational state of the dipole source. Our work provides a promising and robust way to meet the high-resolution and multi-source sensing requirements of underwater vehicles.

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In this paper, we deal with the problem of debugging and revision of incoherent terminologies. Ontology debugging aims to provide the explanation of the causes of incoherence and ontology revision aims to eliminate the incoherence. For this purpose, we propose the graph-based approaches to deal with the debugging and revision of terminologies for a family of lightweight ontology languages, DL-Lite. First of all, we transform DL-Lite ontologies to graphs. To deal with the problem of ontology debugging, we calculate the minimal incoherence-preserving subsets (MIPS) of an ontology by computing the minimal incoherence-preserving path-pairs (MIPP) based on the transformed graph. To deal with the problem of ontology revision, we propose the notion of revision state which separates the terminology of an ontology into two disjoint sets: the set of wanted axioms and the set of unwanted axioms. We further define a revision operator based on the revision state. Afterwards, two revision algorithms are proposed to instantiate the revision operator: one is based on a scoring function, and the other one is based on a hitting set tree. We implement these algorithms and conduct experiments of ontology debugging and ontology revision on several adapted real ontologies. The experimental results of ontology debugging show that our approach of calculating MIPS based on graph is efficient and outperforms the state of the art. The experimental results of ontology revision show that the algorithm based on a scoring function is more efficient than the algorithm based on a hitting set tree.

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The project of a 30m, 35kV/2kA rms , 3 phase, warm dielectric HTS power cable system is underway in China. This system will be installed in China Southern Power Grid at Puji substation of Kunming, Yunan province in 2004. We have carried out a series of experiments to investigate the possible winding angles and layer configurations of the cable conductor with Ag sheathed Bi-2223 tapes, different LN 2 cooling mechanisms, termination configurations, and fabrication techniques. For better understanding of the basics of a HTS cable system and practicing new fabrication techniques, a 4msuperconductor cable with terminations and a close cycle cryogenic system was built and tested. In this paper, we will give out the detailed parameters of the 30m-cable system and the work plan of the project.