After the jet at the middle-lower level become stronger and the cyclonic shear of the basic current of ITGZ increases, the disturbances in ITGZ will develope into typhoons.

The results obtained show that the basic current and disturbances constrain each other, that the basic current alters quasi-periodically with periods of 10 to 13 days, and that the rate of change of basic current in each cycle is quite different.

By using a two-level quasi-geostrophic truncated spectral model, and taking the nonlinear interaction between different wave components (basic current, ultra-long waves and long waves) into consideration, the index cycle of circulation is investigated.

Furthermore, CMOS MOCCII circuit with simple structure has been configured using basic current mirror technique. Both proposed MOCCII filters have been verified by PSPICE simulation,

The filter uses two basic current mirrors and two loss-free integrators, and can realize different kinds of filtering responses by changing input signal forms.

Secondly, we describe the basic current situation from three respects, which are the debt level, the equity structure and debt structure, and compare these with the western developed countries. Appling the capital structure theory, we analyse the flaw of the corporate governance and the negative effect on the corporate value which result from the defect of the capital structure;

Besides, the evolution of a disturbance is determined completely its structure, especially by the direction of its axis and its relative position in the basic current.

The kinetic energy required for the development of these disturbances is probably transfered mainly from the kinetic energy of the basic current with stronger cyclonic shear.

An attempt is made to use the barotropic vorticity equation in spectral form in order to study barotropic instability when the basic current has east-west quasi-stationary asymmetries on the scale of long waves.

An earlier investigation concerning the effect of vertical wind shear in the basic current on the propagation speed and divergence of tropospheric equatorial waves is extended to include the effect of parameterized heating.

Studying discrete symmetry transformations between the 16 differently soldered Cartan bundles, a generalized matter-antimatter conjugation ? is established which leaves the basic current-curvature equations ?-invariant.

The barotropic inertial stability parameter in the eccentrically cyclogeostrophic, basic current field was derived in 2003 from a horizontal cross-stream virtual displacement of a parcel.

Such currents, governed by the eccentrically cyclogeostrophic equation, are adopted as the basic current field for the parcel method.

In this paper,an analysis is made on the structure of the July meanflow field at 850 mb,700 mb,500 mb over the continent of Asia during theyear 1951—1955 and the mean contours at 200 mb over Asia for July andAugust,1956.The vertical cross-sections of the mean flow and temperaturefields along 75°E,90°E,105°E and 120°E for July and August,1956 havebeen constructed.The three-dimensional flow structure over continent ofAsia is constituted of the following three basic currents:(1) the westerliesof middle latitudes,(2)...

In this paper,an analysis is made on the structure of the July meanflow field at 850 mb,700 mb,500 mb over the continent of Asia during theyear 1951—1955 and the mean contours at 200 mb over Asia for July andAugust,1956.The vertical cross-sections of the mean flow and temperaturefields along 75°E,90°E,105°E and 120°E for July and August,1956 havebeen constructed.The three-dimensional flow structure over continent ofAsia is constituted of the following three basic currents:(1) the westerliesof middle latitudes,(2) the upper level tropical and subtropical esterlies,and (3) the south-westerly monsoon under the upper level tropical andsubtropical easterlies.Moreover,the changes of the general circulation over Asia in thetransitional period between spring and summer,1956 is also investigated.It is found that a leaping change of the general circulation over Asiaoccurs during this period.The upper level subtropical ridge was establis-hed over the latitude of Tibet,and over south Asia (to the south of 12°N)an high level easterly jet-stream was established.At the same time,thesouth-westerly monsoon of India and the “Meiyu” (plum rain) season ofthe Yangtze valley set in.The authors also found that the northwarddisplacement of the rain belt is closely related to the northward retreatand the accompanying weakening in intensity of the westerlies over Chinamain land.

With linear two-layer model the development and movement of long waves in the upper and lower part of the troposphere are studied. The main results are:1. The usually used synoptic rules——the disturbance develops when the pressure wave preceeds the temperature wave——is valid only in upper troposphere for ultra-long waves (with wave length of about 10~4 km or larger), valid from middle troposphere upward for long waves of wave length of about 7000 km and valid for whole troposphere for long waves of comparatively...

With linear two-layer model the development and movement of long waves in the upper and lower part of the troposphere are studied. The main results are:1. The usually used synoptic rules——the disturbance develops when the pressure wave preceeds the temperature wave——is valid only in upper troposphere for ultra-long waves (with wave length of about 10~4 km or larger), valid from middle troposphere upward for long waves of wave length of about 7000 km and valid for whole troposphere for long waves of comparatively shorter wave length.2. In the basic current with shear, the upper part of the disturbance develops while the lower part damps when the axis of the trough or ridge line tilts westward with height and the upper part of the disturbance damps while lower part develops when the axis tilts eastward with height. When the upper and lower part develop or damp simultaneously.3. The temperature wave and pressure wave may travel with different speed and their direction of movement may even reverse. In the upper as well as in the lower layer, the disturbance develops (damps) when the ridge moves into the region of divergence (convergence) or the trough moves into the region of convergence (divergence).4. The amplitude as well as the speed of movement of the disturbance varies with time. They depend not only on the structure of the basic current and the wave length bat also on the vertical structure of the disturbance as well.5. The periodically varied stable disturbances may increase or decrease in amplitude more than 250% in one day during the stage of development. Thus the ordinarily observed large variation of circulation in westerly belt may not be a phenomenon of instability.

In this paper the process how an unstable growing disturbance stops developing is investigated. The main mechanism to check the development is the feeding-back effect of the unstable disturbances on the basic current. It is shown that the time elapsed for an unstable disturbance to grow to its maximum intensity is roughly proportional to its initial amplitude. For an amplitude of 100 meters the time is about 8 days, and that for an amplitude of 200 meters is about 5 days. Further, in the vorticity and...

In this paper the process how an unstable growing disturbance stops developing is investigated. The main mechanism to check the development is the feeding-back effect of the unstable disturbances on the basic current. It is shown that the time elapsed for an unstable disturbance to grow to its maximum intensity is roughly proportional to its initial amplitude. For an amplitude of 100 meters the time is about 8 days, and that for an amplitude of 200 meters is about 5 days. Further, in the vorticity and thermodynamic equations we keeped the non-linear terms which are generally dropped. This enables us to study the mutual interaction of the disturbances. It is shown theoretically that this mutual interaction is important in the formation of Ω-shaped blocking highs.