太阳活动短期预报效果及预报评价的探讨

In the paper,the effects of short-term prediction techniques of solar activity of the World Warning Agency (W) and Beijing Astronomical Observatory in 1970s(B7) and 1990s(B9) were analyzed statistically by the standard of the effects of the persistance prediction technique(CH) in the same periods of time. A Q-index evaluating effects of prediction has been put forward;the index indicates the synthesis of positive effects of correct forecasts and negative effects of false forecasts. Against the persistence prediction (CH),the effects of WWA prediction (W),BAO prediction using 1970s' technique (B7) and 1990s' technique (B9) during the same periods of time as (CH) have been evaluated by the Q-index. Based on the above,we have advanced a concrete scientific way to improve the short-term prediction technique. Especially,we have raised that in order to improve prediction technique,the results of persistence prediction should become the basic component of short-term prediction of solar activity;namely,present prediction of forecasting the levels of solar activity should be transformed to forecast the coming change of solar activity levels with the aim of using the effects of persistence prediction fully.     

1982年6月12日耀斑的巴耳末线半宽特征

Usually,because of the Starkbroadening for the spectrum lines,the half widths of hydrogen higher Balmer emission lines of the solar flare increase with the principal quantum number N. Their variation curve,as observed before,has a minimum value near N=8 or 9. However,a curve for the solar flare which occurred at the limb of solar disk on June 12,1982shows an all-time decline with increasing N. How to explain this phenomena remains to be discussed.     

第23太阳活动周的黑子数峰值特征预报

Using the characteristic values of sunspot number variations during the descent and ascent of solar cycles,a neural network is designed to make long-term predications of the ascending period and the maximum smoothed monthly mean sunspot number for the Solar Cycle　23. Moreover,the factor of geomagnetic disturbance is also added as an input. The trained and tested results from Solar Cycle 12 to 22 have been obtained. Finally,the predictions of the ascending period and the maximum smoothed monthly mean sunspot number are given for Solar Cycle 23.     

人造双行星与地球组成的太阳和行星际观测网

A Solar and interplanetary observational system composed of two artificial planets and the earth is suggested for the solar-terrestrial study and prediction.The two planets should move along the earth's orbit around the sun. The angle distance between the two planets and between them with the earth is 120°. This system can be used to improve greatly the short-term,midiu-mterm solar activity predictions and monitor an earth-toward coronal mass ejection,giving an accurate warning of a solar-terrestrial disturbance. Observational data obtained by this system would be very useful in a model work of solar wind and an evolution study of structures in solar atmosphere such as solar active regions and magnetic fields with various scales.     

第23周太阳活动峰年北京天文台太阳射电观测

An introduction to the instrumonts to be used for solar radio observations in Beijing in Solar Cycle 23 is made in this paper. They are 10cm solar radio telescope which has been used for a long time,and 1.0～2.0GHz,2.6～3.8GHz and 5.2～7.6GHz spectrometers. The former two spectrometers has passed a test,showing high guality,and the 5.2～7.6GHz one will be in operation from 1999. It is believed that highl gualified data should be obtained in the next solar cycle.     

第23太阳周黑子相对数的峰值、峰期以及结束期的预测

Two parameters,the smoothed sunspot numbers in the eleventh month during rising phase of the current cycle and the length month of the minimum period (R<14),are selected to predict the maximum-value of sunspot number of cycle 23 in this paper. The predicted maximum-values of smoothed sunspot number are 115<Ri<149 and 114<Ri<146 also predicted by statistical method. The peak-time will be from September,1999 to March,2000,and the end-time will be from August,2006 to April,2008.     

CME与米波射电爆发相关性研究

A correlation between the coronal mass ejection(CME) and the meter wavelength radio bursts is analyzed in this paper. It is found that type Ⅱ and type Ⅳ bursts have very good correlation with CME. Noise storms occur several tens minutes before the onset of the moving type Ⅳ bursts. A sudden stop of noise storms can be used as a sign to foresee the possibility of a following CME. The three kinds of the moving type Ⅳ also introduced in this present papersolated source type,the expanding-arc moving Ⅳ type and the advancing front type.     

空间天气学

Birth and new characteristics of 《Space Weather》 and its base—three kind of the global structure are briefly presented in this paper,respectively.     

射电日像仪天线及工作频率的设想

The article analysizes the current situation and opportunity of the development of radioheliograph in China. It provides an idea to construct the radioheliograph by three stepsfrom small sized,to middle sized,then tobig sized. Each step is to construct a complete radioheliograph. The article also analysizes some important technical performance,such as diameter of element antenna,overall pointing error and observing frequency.     

太阳活动22周低年质子事件的预报分析

In this paper,5 proton events and corresponding active regions in the descending phase of Solar Cycle 22(1993～1995) are analysed. The result shows that (1)The proton flares in 1993～1995 occurred mainly in the longitudy zone of 140～270 degree. (2)4 of 5 events (80%) studied have their small magnetic fluxes to disappear in their magnetic flux regions with a major polarity,one day before the event. (3)It is 60% of the event studied to show characteristic of the merging of 2 or greater than 2 magnetic fluxes with similar polarity in their active regions,one day before of the proton event. The results are possibly useful for the short-term prediction of proton events.     

A Monte Carlo study of rainfall forecasting with a stochastic model

A procedure for short-term rainfall forecasting in real-time is developed and a study of the role of sampling on forecast ability is conducted. Ground level rainfall fields are forecasted using a stochastic space-time rainfall model in state-space form. Updating of the rainfall field in real-time is accomplished using a distributed parameter Kalman filter to optimally combine measurement information and forecast model estimates. The influence of sampling density on forecast accuracy is evaluated using a series of a simulated rainfall events generated with the same stochastic rainfall model. Sampling was conducted at five different network spatial densities. The results quantify the influence of sampling network density on real-time rainfall field forecasting. Statistical analyses of the rainfall field residuals illustrate improvement in one hour lead time forecasts at higher measurement densities.     

Earthquake Engineering and Engineering Vibration Aims And Scope

正This journal is established by the Institute of Engineering Mechanics(IEM),China Earthquake Administration,to promote scientific exchange between Chinese and foreign scientists and engineers so as to improve the theory and practice of earthquake hazards mitigation,preparedness,and recovery.To accomplish this purpose,the journal aims to attract a balanced number of papers between Chinese and     

Foreword

Destructive earthquakes have caused great damage in China and the United States and collapsing buildings havecaused many deaths and injuries. The field of earthquake engineering studies earthquake hazards, the occurrence ofearthquakes of various magnitudes, the nature of the ground shaking during an earthquake, the vibration of structuresduring earthquakes, the strengthening of existing structures and the design of new structures to be earthquake resistant,and finally, how to cope with earthquake damage and restore a city to normal functioning. Such efforts are in progressin both countries, but unfortunately, the language barrier interferes with the free flow of information between China andthe Untied States. It would be mutually beneficial if some means could be developed to promote the exchangeof information across the Pacific Ocean. This new journal has been established for this purpose and its success willbe an important step in promoting earthquake engineering in China and the United States.     

WORLD ASSOCIATION FOR SEDIMENTATION AND EROSION RESEARCH(WASER)

正President:Giampaolo Di Silvio,Italy Vice Presidents:Ulrich C.E.Zanke,Germany Zhao-yin Wang,China The World Association for Sedimentation and Erosion Research(WASER),inaugurated on Oct.19,2004,is an independent non-governmental,non-profit organization.The mission of WASER is to promote international co-operation on the study     

Enhancing remote sensing research on global change to improve our understanding on Earth system processes

正Global Change includes climate change and other environmental changes caused by the joint interaction among various layers of Earth. From the positive side, global change provides new opportunities to human and other living forms on Earth. In the meantime, it creates tremendous challenges and negative impact. At present, the negative impacts have reached all primary processes of the global ecosystem and every aspect of human society, especially causing degradation of the ecosystem. For instance, intensive deforestation causes decline of biodiversity; global warming causes sea level rise and increases     

Dissolved Carbohydrate Concentration,Composition, and Bioavailability to Microbial Heterotrophs in Stream Water

Dissolved total carbohydrates (DTCH), dissolved free monosaccharides (DFMS), dissolved organic carbon (DOC), biodegradable DOC (BDOC), and humic substances (HS) were measured in White Clay Creek (WCC), a stream in southeastern Pennsylvania Piedmont, USA. Samples were collected over different seasons and under baseflow and stormflow conditions. DOC concentrations ranged from 1.0 to 12.8 mg/L C with the highest concentrations associated with stormflows. Carbohydrates ranged from 0.42 to 12.4 μM and accounted for 2.9 to 12.7% of the DOC. Humic substances represented the major DOC fraction, accounting for 55 to 72% of the DOC pool under all flow conditions. The humic fraction had a lower carbohydrate content (4.4%) than the non-humic fraction of DOC (7.2%). Stormflow DOC was enriched in carbohydrates relative to baseflow DOC, but the percentage of humic-C changed little. Carbohydrates were primarily present as dissolved polysaccharides (55%), but a significant fraction was bound to humic substances (40%), while a small proportion was present as monosaccharides (5%). The major monosaccharides in stream water, listed in order of decreasing concentration, included glucose, galactose, rhamnose, xylose, arabinose, mannose, and fucose. On average (30.6 ± 7.4)% (n = 44) of the stream water DOC was biodegradable, and carbohydrates accounted for 9.9 to 17.7% of the BDOC.