Stability, fast-settling and anti-noise abilities are the three necessary parameters to measure the performance of Phase locked lock (PLL). By using of a LPF with strong noise-suppression ability and replacing multiplier of PD with an adder, an improved PLL is proposed in this paper. Compared with the Costas Loop and Saber's PLL, the proposed PLL has better phase tracking ability, shorter settling time, and stronger anti-noise ability. It is expected that our work will be helpful for developing PLL with lower-price and higher-performance, and then contribute to more applications in communication.

576 broilers are experimented on with 6 × 2 (Zn × vitamin A) repetitive experiment in attempt to study the influence of different dietary zinc levels (40,80 ,120 ,160 ,200 and 320 mg/ kg) and dietary vitamin A levels (2700 and 8800 IU/ kg) on vitamin A metabolism, zinc concentration in liver and tibia, zinc apparent deposition rate, serum ALK activity, CuZn-SOD activity in liver and serum, and serum insulin concentration. Results showed that vitamin A concentration in serum increased with the increasing of zinc level in the diet, and that in livers decreased accordingly, which means that zinc can mobilize vitamin A of liver into serum. When dietary zinc level was 320 mg/kg, vitamin A concentration in serum, liver and kidney increased at the same time, perhaps higher dietary zinc level promoted vitamin A absorption except for mobilizing it into serum. Higher dietary vitamin A level (8800 IU/kg) increased zinc concentration in liver and tibia slightly. Zinc apparent deposition rate increased with the increasing of dietary zinc level within certain range and then decreased.；dietary Zinc level has a prominent influence on CuZn – SOD in serum when P < 0. 01; and the result also shows that dietary zinc level, vitamin A level and their interaction has a respectively prominent influence on ALK, serum insulin concentration is also apparently affected.

The wave numerical forecasting model is based on the third generation wave model WAVEWATCHIII, which the analysis wind field of NCEP and the mixed wind field of QSCAT/NCEP are used as the forced field. With the same parameters, the wave model WAVEWATCHIII is established in wave field simulation to China seas. The analysis data of effective wave height from the National Oceanic and Atmospheric Administration (NOAA, USA) is adopted as the verification. It shows that the WAVEWATCHIII model is good agreement with the wave field date using two input wind data. And the QSCAT/NCEP is higher agreement with field data, which means that it is more suitable for wave numerical simulation for China seas.

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