After introducing Haar, Daubechies, W5/3 and D9/7 wavelet, the article uses three steps simplified methods to realize the DWT’s fast algorithm: factoring two-dimensional calculation to one-dimensional calculation along the rows and columns of the image;

With the differentiability of the solution to the initial condition values, the stability and the unstability can be determined for the first constant differential equation such as d y d z =P n(x) n y+…,P 1(x)y+P 0(x) with variable coefficient.

Through study on contrast between combination multifactor and single-factor testing method of mineral processing, this paper affirms that the former is superior to the latter.

An investigation was made for the mid-range forecast of the heavy to torrential rain at the beginning and during the period of the "plum rains" by using synoptic circulation patterns and numerical statistics. It is found that the beginning of the rainy season is closely related with the seasonal northward displacement of the ridge line of the western North Pacific sub-tropical high between 125°-140°E at 500mb. The plum rains occur when the 500mb ridge line is generally stable between 19°-24°N and end when the...

An investigation was made for the mid-range forecast of the heavy to torrential rain at the beginning and during the period of the "plum rains" by using synoptic circulation patterns and numerical statistics. It is found that the beginning of the rainy season is closely related with the seasonal northward displacement of the ridge line of the western North Pacific sub-tropical high between 125°-140°E at 500mb. The plum rains occur when the 500mb ridge line is generally stable between 19°-24°N and end when the ridge line reaches, mostly, 26° or farther north.The forecast of early plum rains should especially be relied on the movement and variation of the sub-tropical high while that of normal or late plum rains should especially be relied on the adjustments arid movements of the westerly short-wave troughs and ridges.It should be noted that the time of the occurrence of the heavy to torrential rain synoptic process during the plum rainy season in Shanghai is related with the region in which the interaction of cold and warm air masses take place, the characteristics of their intensity variations and also with the variations of the meteorological parameters at the stations concerned.

In this paper the role of summation in classical Cowell's method is discussed. It is not only proved that the second-sum formula is algebraically equivalent to the formula in which no summation is employed,but also that contrary to the tradi- tional view such algorithm cannot efficiently reduce the accumulation of round-off error.Therefore,the second-sum formula hardly has any advantage.But when the first-sum formula is used,the accumulated round-off error is about O(h) times that of primary formulas,in which...

In this paper the role of summation in classical Cowell's method is discussed. It is not only proved that the second-sum formula is algebraically equivalent to the formula in which no summation is employed,but also that contrary to the tradi- tional view such algorithm cannot efficiently reduce the accumulation of round-off error.Therefore,the second-sum formula hardly has any advantage.But when the first-sum formula is used,the accumulated round-off error is about O(h) times that of primary formulas,in which h is the step length.Here the value of partial double precision arithmetic is also discussed.This arithmetic might reduce the accumulated round-off error which is about O(h~2) times that of primary arithmetic,but in this case there is not any advantage to use the first-sum or second-sum formula.

It is considered in this Paper that the poor and good harvest ofwinter wheat in Shanxi Province depends on the key factor-autumnrainfall in the sowing stage and the early growing period of young seed-lings (from the middle of September to late November), with the droughtequivlant of 75 mm based on an analysis of rainfall information of 867years of 43 county weather stations and the winter wheat yielding infor-mation by means of the principle of drought equivalent of the well-known ecologist G. Azzi. The second...

It is considered in this Paper that the poor and good harvest ofwinter wheat in Shanxi Province depends on the key factor-autumnrainfall in the sowing stage and the early growing period of young seed-lings (from the middle of September to late November), with the droughtequivlant of 75 mm based on an analysis of rainfall information of 867years of 43 county weather stations and the winter wheat yielding infor-mation by means of the principle of drought equivalent of the well-known ecologist G. Azzi. The second important stage is the rainfall(from December to February next year) in the winter dormancy withthe drought equivalent of 40 mm.In the above growing period of winter wheat, it can be divided intothe rare belt of drought frequency (2.5-5), the intermediate-long belt ofdrought frequency (2.5-5) and the usual belt of drought frequency (7.5)according to the drought frequency (still less than 2.5) from the southto the north. It can be further zonifized into the microarid region, thelight-arid region, the arid region and aridest region for winter wheatin Shanxi Province based on the relationships between the drought fre-quency and distribution of winter wheat.The geographical experiment illustrated that the selection of wheatvarieties of rainfed lands and the climatic constraints are the first, butthe soil constraints are the second. It is obvious that reduction withless in the drought year or even reduction without any yield can entirelybe avoided by the use of drought-resistant varieties against drought anddryness under the existing conditions. On the other hand, if, in a goodyear, the unsuitable varieties are selected, the favourable rainfall watermay not be used to the fullest extent, so that the due bumper harvestcan not be won. The non-extreme drought is a common phenomenon, theoccurrence and frequency of which have a close relation with the fluc-tuation of yields of winter wheat.