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the coherent and incoherent features of internal tides (its) in the north South china Sea (ScS) are investigated based on observations and numerical simulations. The 11-month (from May 2011 to March 2012) moored current observations indicate that coherent semidiurnal ITs are obviously amplified, which can be attributed to the interference of ITs. Interference enhances coherent motions of semidiurnal ITs, but weakens those of diurnal ITs. Moreover, observations also show that semidiurnal ITs are more incoherent than diurnal ITs. Variations of vertical stratification and surface tide forcing can hardly affect the incoherence of ITs. The increase of incoherent signal is largely due to the influence of mesoscale eddies. Mesoscale eddies affect both amplitude and phase of ITs, making them more incoherent. Mesoscale eddies not only increase the intensity of background currents, but also induce horizontal variations of density. Variations of horizontal density and the influence of background currents lead to the increase of incoherent signals. And semidiural ITs are more sensitive to the influence of mesoscale eddies, making them more incoherent than diurnal counterparts. Incoherent ITs, which induce strong current shear, play essential roles in cascading tidal energy to small-scale motions, and contribute to turbulent mixing eventually. The findings help to better understand ITs and may offer reference for the improvement of parameterization of ocean turbulent mixing in the northern ScS. Internal tides (ITs) are commonly generated in stratified oceans by barotropic tidal currents flowing over seamounts, ridges and continental shelf breaks 1-4. As an essential intermediate step of tide-to-turbulence cascade, ITs play important roles in dissipating surface tidal energy and enhancing mixing, which contribute to deep-water circulation 5-10. Munk found that the breaking of ITs provides nearly half of the energy necessary to maintain the global meridional overturning circulation 11. The Luzon Strait (LS), which is featured by two north-south oriented ridges, connects the western Pacific and South China Sea (SCS). At the LS, strong diurnal and semidiurnal ITs are generated when barotropic tides flow over the double ridges 12. ITs propagate westward into the SCS, making it a region with strong ITs 13-15. Wang et al. found that the ITs radiating from the LS dominate the tidal dissipation in the SCS. Without the ITs generated at the LS, the dissipation in the SCS will be at least one order of magnitude smaller 16. Coherent ITs are phase-locked with barotropic tides at the generation site. Variability of coherent ITs is primarily explained by spring-neap cycles in barotropic tides. During their propagation, incoherence grows and ITs lose coherence to surface tides 3,4,17,18. In the Bay of Biscay, incoherent semidiurnal signals explain 30% of the total motions 19. Eich et al. attributed the growing of incoherent semidiurnal ITs in the Mamala Bay to the influences of both variable stratification and mesoscale motions 17. Many scale...

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In biological research, biology sequence alignment algorithm aims to find similarities between sequences. As the size of biological database increases exponentially, the complexity of sequence alignment process also increases rapidly, which results in a large amount of computational time. The Sunway TaihuLight is the world's first heterogeneous supercomputer with peak performance over 100 PFlops and provides a new hardware platform for database search. In this paper we present an efficient method of protein database search based on Sunway TaihuLight supercomputer. Furthermore, we also optimize protein database search on Sunway TaihuLight to give full play to the performance of the SW26010 processor. In our proposed approach, we design hybrid sequence alignment by combining the Smith-Waterman local alignment algorithm and the Needleman-Wunsch global alignment algorithm. The protein database search is paralleled by message passing interface (MPI) and accelerated thread library (Athread). Experiment results with the Swiss-Prot database show that our implementation can effectively leverage the SW26010 processor's special hardware architecture and achieve a speedup to 15.91 times on a single node. In addition, we expand the scale to 64 nodes to test the scalability of the parallel method on the Sunway TaihuLight system, and the results show that our parallel implementation of protein database search have a good expansibility and reliability.

This paper is concerned with the problems of finite-time stochastic H ∞ control for singular Itô Markovian jump systems with (x, v)-dependent noise and generally uncertain transition rates (GUTRs). Based on two equivalent sets, a new criterion, ensuring the considered systems with completely known TRs to be finite-time stochastically bounded with H ∞ performance, is first established, which is less conservative than the existing one. Then, the obtained results are extended to the case of GUTRs. To overcome the nonlinear difficulty resulting in the Young inequality for designing a convex controller, an approach called the association of free variables and slack variables are used. The state feedback controller and observerbased controller are respectively designed such that the corresponding closed-loop systems with GUTRs are finite-time stochastically bounded while achieving H ∞ performance. Finally, the numerical examples are addressed to illustrate the effectiveness and efficiency of our obtained results. INDEX TERMS Singular stochastic Itô systems, Markov jump systems, finite-time H ∞ control, generally uncertain transition rates.