The three-layer model of the thermohaline structure in the shallow seas

A three-layer model of the thermohaline structure is developed on the basis of the two -layer model of thermocline. The model is able to simulate the depth,thickness and intensity of both thermocline and halocline, and the temperature and salinity of both upper layer and lower layer in the shallow seas.Camparison of simulation with data is favorable.Detailed analysis is made on a variety of factors affecting the intensity of the thermocline.

A three-layer model for the thermal structure in the Huanghai Sea

A one-dimentional three-layer model for the thermal structure in the Huanghai Sea is presented in this study, me model consists of the upper mixed layer caused by heating and wind mixing, the lower mixed layer driven by tidal mixing, and the thermocline with certain thickness. The entrainment velocities of the upper and lower layers are obtained respectively. The results show that the model is capable of describing the development and decline processes of the seasonal thermocline in the Huanghai Sea, simulating successfully the Huanghai Sea Cold Water Mass, the nearshore front and surface cold water off North Jiangsu and explaining reasonably their formation mechanisms as well as the strong thermocline off Qingdao. It is suggested that the tidal mixing plays key role in the formation of the nearshore front off North Jiangsu and the strong thermocline off Qingdao. The wind mixing and the tidal mixing make the lower layer water with high nutrients go up to the upper layer. This physical process may be significant for biological plant production.

A Model for the Sounding Rocket Measurement on an Ionospheric E-F Valley at the Hainan Low Latitude Station

To understand the physics of an ionospheric E-F valley, a new overlapping three- Chapman-layer model is developed to interpret the sounding rocket measurement in the morn- ing （sunrise） on May 7, 2011 at the Hainan low latitude ionospheric observation station （19.5°N, 109.1°E）. From our model, the valley width, depth and height are 43.0 km, 62.9% and 121.0 km, re- spectively. From the sounding rocket observation, the valley width, depth and height are 42.2 km, 47.0% and 123.5 km, respectively. The model results are well consistent with the sounding rocket observation. The observed E-F valley at Hainan station is very wide and deep, and rapid deel- opment of the photochemical process in the ionosphere should be the underlying reason.

Neuroid BP-type Model Applied to the Study of Monthly Rainfall Forecasting

A neuroid BP-type three-layer mapping model is used for monthly rainfall forecasting in terms of 1946-1985Naming monthly precipitation records as basic sequences and the model has the form i×j=8×3, K=1; by steadilymodifying the weighing coefficient, long-range monthly forecasts for January to December, 1986 are constructed and1986 month-to-month predictions are made based on, say, the January measurement for February rainfall and soon, with mean absolute error reaching 6,07 and 5,73 mm, respectively. Also, with a different monthly initial value forJune through September, 1994, neuroid forecasting is done,indicating the same result of the drought in Naming during the summer, an outcome that is in sharp agreement with the observation.

引入强分层近似对含密度跃层情况下的大幅内孤立波计算误差研究

At present,studies on large-amplitude internal solitary waves mostly adopt strong stratification models,such as the twoand three-layer Miyata–Choi–Camassa(MCC)internal wave models,which omit the pycnocline or treat it as another fluid layer with a constant density.Because the pycnocline exists in real oceans and cannot be omitted sometimes,the computational error of a large-amplitude internal solitary wave within the pycnocline introduced by the strong stratification approximation is unclear.In this study,the two-and three-layer MCC internal wave models are used to calculate the wave profile and wave speed of large-amplitude internal solitary waves.By comparing these results with the results provided by the Dubreil–Jacotin–Long(DJL)equation,which accurately describes large-amplitude internal solitary waves in a continuous density stratification,the computational errors of large-amplitude internal solitary waves at different pycnocline depths introduced by the strong stratification approximation are assessed.Although the pycnocline thicknesses are relatively large(accounting for 8%–10%of the total water depth),the error is much smaller under the three-layer approximation than under the two-layer approximation.

Material parameter modeling and solution technique using birth–death element for notched metallic panel repaired with bonded composite patch

This paper seeks to outline a novel three-layer model and a new birth-dteath element solution technique to evaluate static strength of notched metallic panel repaired with bonded com- posite patch and to optimize material parameters. The higher order 3D, 8-node isotropic solid ele- ment and 8-node anisotropic layered solid element with three degrees of freedom per node are respectively implemented to model substrate panel, adhesive layer and composite patch to establish three-layer model of repaired panel. The new solving technique based on birth-death element is developed to allow solution of the stress pattern of repaired panel for identifying failure mode. The new model and its solution are used to model failure mode and residual strength of repaired panel, and the obtained results have a good agreement with the experimental findings. Finally, the influences of material parameter of adhesive layer and composite patch on the residual strength of repaired panel are investigated for optimizing material properties to meet operational and envi- ronmental constraints.