Abstract:In terms of EOF analysis,the variability of the oceanic subsurface temperature,divergence,zonal current velocity,and surface zonal wind stress on the vertical cross-section along the equator(0°) in the tropical Pacific Ocean and their relations are discussed.Results show that the first two EOF modes represent the dominant component of the above physical quantity fields,with the second mode ahead 8 months of the first mode.The first two and fourth physical quantity fields mentioned above varied almost synchronistically,3-4 months ahead of the variation of zonal current.So it is deduced that when there exists zonal westerly(easterly) wind stress anomaly over the tropical Pacific Ocean,the upper water mass convergences(divergences) and the lower water mass divergences(convergences) results in the anomalous downwelling(upwelling) of water mass,which leads to an increase(decrease) of subsurface sea temperature and a westward(eastward) velocity anomaly of zonal current.

Abstract:Using the NCEP/NCAR monthly mean tropopause pressure and temperature reanalysis data from 1979 to 2002,we have investigated both the interannual and interdecadal variabilities of the wintertime tropopause.The tropopause pressure index is defined as the areal average over the region where the tropopause pressure variability reaches its maximum.The tropopause temperature index is defined in a similar way as for the tropopause pressure index.Results show that the global tropopause pressure and temperature averaged over 24 years increased with the increase of latitude.However,the distributions of the tropopause pressure and temperature in the tropics and the high latitudes were relatively homogeneous.The globally mean tropopause pressure and temperature were descending during the winters from 1979 to 2002,and these results agree with the results from part of sounding data.The subtropics in the Northern Hemisphere was the region where the maximum tropopause variability is found,while the tropopause variability reached its minimum in the low latitudes.The periodicities of pressure and temperature indices are found to be dominantly the 13 years and 3-6 years.There was prominently positive correlation between the tropopause pressure and temperature in the most of world,while the correlation between the tropopause pressure and tropospheric mean temperature was significantly negative in the most of world.

Abstract:Replacing the RegCM2 runoff scheme with the heterogeneous surface runoff algorithm which is suitable to the loosen and compact soils,this paper designs a hydrological model being coupled with RegCM2,and simulates the discharges of the two important hydrological stations in the Yangtze basin,which are verified by the observation value.The monthly precipitation of June,July and August 1998 during the rain storms is simulated by the coupling model,and the impact of the runoff scheme on simulated precipitation,surface heat fluxes,runoff and soil moisture is analyzed.The results show that(1) the runoff scheme is reasonable for simulating the precipitation distribution during the rain storms in 1998,and improves to some extent precipitation simulation,about 10% of total precipitation;(2)the runoff scheme changes timely the heat fluxes from the surface to the atmosphere which are connected with the reassignment of the surface water;(3)this scheme enhances the soil infiltration,resulting in less runoff during the early period of rainstorm,and more runoff during the last period;(4)the consistency of simulated and observed discharges shows that the coupling model has capacity to represent the hydrological process in the Yangtze basin during the heavy rainstorms in 1998.

Abstract:Based on the FSU(Florida State University)monthly analysis data of wind stress,typical wind stress patterns associated with the El Nino/La Nina are determined with the technique of POP(Principal Oscillation Pattern) analysis.The results show that the oscillations of zonal/meridional wind stresses have the periods of 35,47,57 months/28,38 months,respectively.We also found the coupled relations between zonal/meridional wind stress propagating patterns and ENSO oscillations.It is suggestive that the explanation,simulation and prediction of El Nino/La Nina spatial/temporal evolution should not be based on a single eigenmode but on their interaction,with emphasis on the fact that superimposition and phase locking are important factors for the event cycle.Finally,the authors suggest that the local oscillation is worthy of consideration too.

Abstract:The unconditional and conditional probability density functions of daily precipitation are estimated by use of the 1961-2000 summer daily precipitation data of 174 stations in China,and the probability distributions of maximum daily precipitations,and of the maximum daily precipitation greater than or equal to 10 mm,25mm,and 50mm within 10,and 20 days for each station are derived,respectively.The main results show that the differences of the Gamma distribution shape parameter α of daily precipitation under no condition,and the condition of a wet/dry preceding day at different stations are not too large,and all α are smaller than 1.While the scale parameter β of the Γ distribution,to the overwhelming majority of stations,the unconditional β is greater than the dry preceding day β₀ and less than the wet preceding day β₁.Both unconditional and conditional μ and σ² in the southeast coastal region are greater than those in the northwest inland area;and for the overwhelming majority of stations,the unconditional μ are greater than the dry preceding day μ₀ and less than the wet preceding day μ₁,and the same to the variance of Γ distribution.Γ distribution can accurately approximate to the sample frequency distributions of daily precipitation under the conditions of a wet or dry preceding day.The probability distributions of the daily maximum precipitation greater than 10mm,25 mm,and 50 mm within 10 days,and 20 days in the southeast coastal region are all greater than those in the northwest inland area,respectively,approaching to the geographic distributions of the sample frequency of the same rainfall order.The high value area of probability lies in the west of Guangxi and the east of Yunnan,and the secondary high value area in the south of Anhui and the north of Jiangxi.

Abstract:Experimental studies were conducted at the Yucheng Comprehensive Experimental Station of the Chinese Academy of Sciences during the period from March to June in 2003.Respiration of a pulverous sandstone soil was studied under cultivation of winter wheat over a growth season.Soil CH₄ was measured by the Static-Chamber method combined with the Gas Chromatography（GC） technique.Results indicated that the soil of winter wheat field in the rapid growth season is a weak sink of CH₄.Uptake of CH₄ by the soil showed an obvious seasonal and diurnal variations in this period of time.The mean value of CH₄ fluxes was-18.3 μg·m^-2·h^-1,and the range from-4.3 to-24.4 μg·m^-2·h^-1.There were two peaks at day and night time respectively,and the time of peaks varied with the change of wheat growth.The relationship between daily mean soil CH₄ flux and soil temperature was not remarkable,but a closely negative correlation was found between soil CH₄ fluxes and soil moisture（α=0.01）;and the diurnal soil CH₄ flux was also closely related to temperature not of the soil surface but of 5cm depth.Soil CH₄ fluxes would reduce with increase of NH₄⁺ concentration,and Straw's retention went against soil oxidation of CH₄.

Abstract:The comparison of the interdecadal and interannual characteristics of the atmosphere-ocean system between the tropical and extratropical Pacific is made in this paper.Results show that the interdecadal anomalies are more significant in the variance of the system anomaly in the North Pacific(NP),and the interannual and interdecadal anomalies are about equivaleut in the tropical Pacific(TP);the interdecadal change characters of the surface(shallow)layer of the ocean and the atmosphere aloft are unanimous in the same season and region,and their transition from a low mode to a high mode both occurred from the end of 1970s to the beginning of 1980s,with an exception for July in the NP,which is related to the stability of the stratification of sea temperature within the sub-surface layer;the interannual scale air-sea anomalies are associated with ENSO,which is most typical for January,then July in the TP,followed by January in the NP,and there is no visible relationship for July in the NP.

Abstract:The spatial patterns of Jiangsu temperature trends and inter-decadal variations(1961-2001) are investigated by using the monthly mean temperatures of 60 weather stations in Jiangsu Province.Results show that:the regional annual mean temperature rose by about 1℃ in the study period,with maximum warming(cooling) in December to February(July to August).Inter-decadal variations of seasonal mean temperatures are somewhat similar to the annual counterparts in such a way that the these temperatures decreased on the whole in the 1960s,and fluctuated in the 1970s to early 1980s,followed by rapid increasing in the later 1980s to 1990s.As a result,the highest temperatures of annual,spring,autumn and winter occurred in the 1990s,except that the summer temperatures droped more or less in the late 1990s,with its maxima measured in the 1960s.The spatial differences in trends and inter-decadal variations lie mainly in the range of temperature change.Generally,spring,autumn,winter and annual mean temperatures rose all over the whole province,and especially winter to spring and annual means rose most distinctly in Suzhou,Wuxi,and Changzhou in the southern part of the province,and Xuzhou and Lianyungang in the northern part,with the maximum autumn warming observed in the southern part(Suzhou,Wuxi,and Changzhou).Summer temperatures showed dropping trends in most areas of the province,particularly in the east coastal area and southwest Jiangsu,which is in sharp contrast to weakly rising trends in part of the northern Jiangsu.

Abstract:Based on the 1951-2001 dekad mean rainfall of 9 stations in northeast China,northeast China rainy season is demarcated.The initiation,termination,duration and rainfall of rainy season are determined and the relationships among these characteristic quantities discussed.The atmospheric circulation variations at the beginning and end of rainy season are compared.And the lag correlation between rainy season characteristic quantity and SST anomaly in tropical ocean key regions is investigated.Results show that:(1) the rainy season begins in the first-second dekad of July,and ends in the first-second dekad of August,and the rainy season rainfall is closely related to the Z index of the total rainfall of 9 stations in summer,indicating that the rainy season rainfall reasonably reflects the summer precipitation features of the region;(2) generally speaking,when the rainy season begins earlier,it always persists for a longer period,and its rainfall is greater,and when the rainy season begins later,the inverse is also true;(3)the northeast China rainy season is principally controlled by the East Asian summer monsoon:when the East Asian summer monsoon strengthens and marches northward,the rainy season begins,and when the East Asian summer monsoon weakens and withdraws southward,the rainy season terminates;and(4)the seasonal SSTA over the tropical ocean is a precursor on the scale of short-range climate prediction to the rainy season features in northeast China.

Abstract:A same cloud has different view-angles when it moves from overhead toward the near-horizon.In this paper,we simulate the track of the cloud's movement based on the principle of the equi-angle projection of all-sky imager(fish-eye lens) and estimate the cloud fraction during its movement.The cloud is simplified as the cubic and cylindric objects of two different sizes in the simulation.To get the characteristics of variations of the cloud fraction,we calculate the cloud amount and the ratio of the cloud's frank-fraction to the cloud-fraction during the movement of the cloud.Results show that the variation of the cloud-fraction is related to the ratio of the cloud's base to height(RBTH).When the RBTH is larger than a threshold,the cloud-fraction will increase at first and then decrease with the zenith angle's increase.Otherwise,it will decrease all the time.The degree of the decrease is related to some parameters such as the height,RBTH and size of the cloud.And the frank-fraction will account for more and more portion of the whole cloud cover when the zenith angle increases.

Abstract:A new forecast application of numerical forecast products is exemplified by use of artificial neural network(ANN) to daily forecasts of the regional average precipitation of Guangxi in May and June.Three different regional rainfall forecast models are established based on the useful information concentrated from numerous T213 factors by Empirical Orthogonal Function(EOF),and the forecast factors of the Japanese precipitation model.Daily operational forecast trial of the three regional ANN models were made in May and June 2004,and their forecasts compared day-by-day with ones of T213 numerical model.The results show that the three regional ANN forecast models are superior to T213 in daily precipitation forecast in the period.The prospects for the application of numerical forecast products are encouraging.

Abstract:The wind retrieval of the single-Doppler radar data under different weather conditions is performed using the single-elevation and multi-elevation VAD techniques,and the results are compared.On the basis of the comparison,this paper puts forth the selfadapting elevation VAD method,which combines merits of the above techniques.It is shown from retrieval results that the former two methods have their own merits and demerits,while the selfadapting elevation VAD method is able to get more valuable information on some occassions.

Abstract:The observational characteristics of cloud-ground lightnings and precipitation for 8 storms during 2000-2001 are investigated,and radar echo,and lightning feathures for two types of heavy-rain and hail-producing weather are analyzed detailedly.There are apparent differences of lightning features between heavy-rain and hail-producing weather.The hail-producing weather has more positive lightnings,and especially at the time just before hailfall the positive lightning frequency increases rapidly.In addition,it is also found that lightnings often occurred within radar echoes of more than 45 dBZ in the studied cases,which is a little higher than the 30-45 dBZ in mid-latitude region suggested by previous studies.

Abstract:We consider asymptotic behaviors of stationary tail probabilities in the discrete time quasi-birth-and-death(QBD) process with a countable background state space.Applying the Markov renewal theorem,it is shown that certain reasonable conditions of the QBD process lead to the geometric decay of the tail probabilities as the level goes to infinity.We exemplify this result using a time-discretized joining the shortest queue model.

Abstract:By using of the theory of compactness,the initial and boundary value problem for a class of degenerate reaction-diffusion system is considered.The global existence and uniqueness of solutions to the equation are discussed.

Abstract:By using the daily mean rainfall data of 26 stations in South China from 1958 to 2000,the climatic features of the rainfall of rain storms during the preflood season in South China have been studied.The results show that :(1)the rainfall of rain storms and its frequency exhibited obvious interannual and interdecadal decreasing tendencies;(2)about one half of the rainfall of rain storms precipitated in the preflood season with the maximum center in Fujian and the north-west of Guangdong and the minimum in the southwest of South China;(3)the rainfall of rain storms accounted for about 40% of the total rainfall of the preflood season,and the maximum percentage(nearly 44%) of rain storm rainfall laid in the coastal area of Guangdong,and two minimum centers(about 26%) in Fujian and the east and west of Guangxi.

Abstract:With the aid of the NCEP/NCAR monthly reanalysis data-set and the summer precipitation data in the east of northwest China during 1951-2002,the interannual variability of cross-equatorial flow and its influences on summer precipitation in the east of northwest China are analyzed.It is concluded that the cross-equatorial flow has strengthened and is more persistent since 1951;and the Somali jet is the principle and stable cross-equatorial flow,and also an important circulation factor which affects the summer precipitation in the east of northwest China.

Abstract:SVD analysis of the relationship between northern Jiangnan Meiyu season precipitation anomalies and sea surface temperature anomalies(SSTA) shows that correlated SSTA distribution displays a pattern of west-positive-east-negative.The key region is just located in the most significant correlation area.The time period of the significant SSTA impact is from October to December in the previous year,i.e.the SSTA in the period is closely positively correlated with the Meiyu precipitation in northern Jiangnan.Under the influence of the SSTA pattern,the precipitation anomalies in the following Meiyu period in northern Jiangnan would exhibit a in-phase feature,and the most remarkable correlation region is the south part of the lower reach of the Changjiang River.

Abstract:In the light of different structures of environment and information which are derived from the complexity and diversity of current information management systems in Chinese spinning enterprises,this paper puts forth a new framework and solution on the key technologies of Chinese spinning enterprises resource planning(ERP) integrated system based on virtual private network(VPN) and multi-tier Web.The purpose of the paper is to make the process of information management in spinning enterprises more intellectualized,standardized,dynamic and safe.The system discussed in this paper is efficient in making good use of resources and providing maximum benefits.

Abstract:The process of transplanting the embedded OS(μC/OS-Ⅱ) to an ARM processor(S3C44BOX) is described detailedly,with a developing board of uCdragon Corp.As a hardware-Platform,after the OS and its transplantation conditions are introduced.And how to expand the RTOS system structure is discussed in this paper as well.

Abstract:To accommodate to new requirements of weather services,the integration between the current different application systems and databases should be enforced,and the search of data memorized and the share of data information also should be enhanced.Aiming at the demand in integrating the existing data resources,and in conceiving the uniform information platform,we evaluate the applicability of J2EE in building the multi-layer meteorological information system,set up the basic structure of the system based on J2EE,and utilize JDBC to put up the consolidated operation among the isomerous and dispersive databases.By means of JAAS and electric signature,we strengthen the security of the whole system and data in the process of information sharing,and discuss the application of J2EE technology in constructing the distributed and dynamic meteorological information system.

Abstract:An intelligent method to develop exam and quiz sheets for an online test system is presented in this paper.The intelligent method applies an adaptive crossover rate and mutation rate's biologic genetic algorithms to the question selection for exam and quiz sheets.The mathematic model consists of genetic iteration,sample adaptability function,mating probability,aberrance probability,optimum selection and error estimation.All details of the coding and operation of the model are shown in the paper,and the results of the experimental applications of the model are also discussed.The running time and error analysis show that the improved genetic algorithm is more satisfying compared with the traditional Simple Genetic Algorithm and Probability Method.In the paper some technique procedures and key skills for developing online test system are introduced,which are based on Personal Home Page(PHP) and database MySQL applications.