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51.
Leiming Ma 《地球科学进展》1986,35(6):551-560
Numerical weather prediction, which is the major basis of current weather forecast, has some shortcomings, such as the understanding of the law of atmospheric motion, the assimilation and application of observation data, the expression of model physics, etc., leading to the forecast error of weather. The rapid development of artificial intelligence technology in recent years provides a new possibility for the advancement and innovation of weather forecast. In this paper, the background of the development of artificial intelligence, the current situation of the application of artificial intelligence technology to weather forecast and the future development trend are mainly described to account for this possibility. After that, the idea for development of weather forecast technology based on the integration of artificial intelligence and numerical forecast is put forward. Particularly, this study stresses that, in order to advance the AI algorithm of weather forecast in the future, it is requested to focus on the nonlinear and chaotic characteristics of atmospheric motion leading to the uncertainty of forecast. Starting from the essence of mathematics and physics, we need to realize the hybrid modeling of mathematics and physics, not only to establish the framework of input-output mapping, but also to provide solutions to the bottleneck problems of weather forecast. 相似文献
52.
Fate and effect of copper and cadmium on the degradation of chitin were studied in sediment microcosms. Artificial sediment was spiked with metals, and metal partitioning between sediment components, overlying water and bacteria was described. Most of the added metals were bound to sediment particles. Remarkable metal enrichments were found on Fe-oxide, Mn-oxide, and chitin. In sediments containing the nominal concentration of 100 mg/kg Cu, the chitin-degrading bacteria Cytophaga johnsonae showed a significant decrease in N-acetylglucoseaminidase activity. Toxicity of copper was attributed to free ions in the overlying water. The bacteria were more sensitive to copper than to cadmium. Inhibitory effects of cadmium were primarily caused by sediment-associated cadmium. 相似文献
53.
国内外的台网中总是一些台站,其极性读取似乎是由大量台站P波初动的整体分布确定的震源机制相矛盾,这些矛盾通常被作为坏读(bad reading)处理,造成台站的极性问题的复杂原因究竟是什么,利用NEIC的核爆资料,文中给出两种可能推测:台站仪器本身的不可和地震本身的复杂性。 相似文献
54.
Summary An overview of economics and design consideration for explosive overburden casting is given and the criteria for the successful application of this technique are discussed. These criteria are: blast design, economic considerations and environmental considerations. Explosive overburden casting may effect considerable cost savings if the market for increased production is available. However, if a fixed sales constraint exists the economic benefits of explosive overburden casting may be marginal and an extensive economic analysis is warranted. 相似文献
55.
In this paper, a simple scenario and probabilistic approach is used to assess the potential groundwater risk due to proposed
overdraft remedial actions in cone of depression, Jining City, China. Focusing on the concentrations of Chloride ions (Cl−) and total hardness (TH), the impact of artificial recharge and reduced pumping on groundwater quality and quantity is analysed
by using the three-dimensional finite difference groundwater flow and transport model, Visual MODFLOW, to simulate groundwater
flow and transport within the study area based on scenarios, and utilizes SURFER software to map risk levels. Although 5,
10 or 15% reduced pumping with artificial recharge leads to more decrease in Cl− and TH concentrations than the 25%, less volume increase is achieved for the remediation of land subsidence and other environmental
problems in the cone of depression. The Cl− concentrations in recovered groundwater are within the desired concentration of 200 mg/l; however, TH in some cases are above
the maximum permissible limit of 500 mg/l, with an exceedence probability of about 0.67 for recharge and recharge with reduced
pumping at 25%. The presence of fractures and hydrogeological complexity greatly determines impacts of remediation, and the
22% reduced pumping with artificial recharge offers an optimum strategy for overdraft remediation in the Jining cone of depression. 相似文献
56.
神经网络作为一种新的方法体系,具有分布并行处理、非线性映射、自适应学习和鲁棒容错等特性,在模式识别、控制优化和智能信息处理等方面有着广泛的应用。利用MatLab的神经网络工具箱,建立了江苏矿山地质环境质量的评估模型,评估结果经过实际验证,具有较高的可信度和实用性。 相似文献
57.
Sokrat Amataj Todor Anovski Ralf Benischke Romeo Eftimi Laurence L. Gourcy Liliana Kola Ioannis Leontiadis Eftim Micevski Alqiviadis Stamos Jovan Zoto 《Environmental Geology》2007,51(5):749-753
Prespa Lake and Ohrid Lake constitute a hydraulic system shared between Albania, FYR of Macedonia and Greece. Karst rocks
separate both lakes. The elevation of Prespa Lake is about 150 m higher than that of Ohrid Lake. Considering these facts,
Cvijić formulated in 1906 the hypothesis that Prespa Lake recharges the St. Naum and Tushemisht springs at Ohrid lakeside.
Environmental isotopes demonstrated that Prespa Lake recharges about 37–42 and 52–54% of water emerging in St. Naum, and Tushemisht
springs, respectively. An artificial tracer experiment carried out in 2002 physically demonstrated the underground connection
between both lakes. This experiment confirmed the supposed underground connection and brought important information about
the groundwater velocity, transit time, and karst water conduits development. 相似文献
58.
59.
This paper explores the application of Artificial Intelligent (AI) techniques for climate forecast. It pres ents a study on modelling the monsoon precipitation forecast by means of Artificial Neural Networks (ANNs). Using the historical data of the total amount of summer rainfall over the Delta Area of Yangtze River in China, three ANNs models have been developed to forecast the monsoon precipitation in the corre sponding area one year, five-year, and ten-year forward respectively. Performances of the models have been validated using a 'new' data set that has not been exposed to the models during the processes of model development and test. The experiment results are promising, indicating that the proposed ANNs models have good quality in terms of the accuracy, stability and generalisation ability. 相似文献
60.