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991.
“北京气象”手机客户端气象信息GIS快速可视化技术 总被引:3,自引:0,他引:3
随着移动互联网和智能手机技术的发展,客户端APP应用是满足便捷、高效、可移动、可定位气象信息服务的重要途径和手段。通过对格点天气、雷达回波、专题图等更新频次高、空间分辨率高、数据量较大的气象信息手机客户端GIS快速可视化关键技术的研究和实践,提出在服务器端应用支撑层部署Surfer专业绘图软件,在客户端数据资源层部署Google预先渲染好的离线栅格瓦片地图,应用支撑层部署开源的OpenLayers WebGIS二次开发组件,在两端应用逻辑层采用数据缓存和分布式存贮技术的手机客户端气象信息GIS快速可视化J2EE技术架构,实现了格点产品、雷达回波、专题图等气象信息GIS快速可视化展示。 相似文献
992.
介绍KIS地震仪表系统的功能与软件的结构组成,对软件开发中存在的问题及下一步发展方向进行探讨。 相似文献
993.
西秦岭北缘断裂带和海原断裂带断层泥粒度分布和分形研究 总被引:1,自引:0,他引:1
用筛选法和悬浮法相结合的方法对采自西秦岭北缘断裂带东段和海原断裂带西段的天然断层泥进行了粒度分布和分形研究。
研究结果表明 这2条断裂带断层泥粒度组成为粗粒级(Φ<4)含量高,细粒级(Φ≥4)含量低;
断层泥分维值分别为2.594±0.122和2.654±0.112,分维上限分别为2 cm和1 cm。 相似文献
994.
黑龙江省农业气候背景分析 总被引:4,自引:0,他引:4
概述了黑龙江省的主要气候特征,介绍了主要农业气候资源状况,分析了气候变化与发展趋,并初步探讨了气候变化对黑龙江省农业生产及生态环境的可能影响. 相似文献
995.
996.
Kepiao Xu Lei Zhong Yaoming Ma Mijun Zou Ziyu Huang 《Theoretical and Applied Climatology》2020,139(3):1031-1044
This study presents results of the pilot experiments made with new parametric multi-site multi-variable stochastic daily weather generator (WG) SPAGETTA. The experiments are performed for eight European regions and we focus on spatial characteristics of temperature. The WG is calibrated using the gridded weather data E-OBS. In evaluating the generator, the spatial and temporal temperature autocorrelations derived from the synthetic series were found to perfectly fit the values derived from the calibration data. Next, the WG is validated in terms of the frequency of “spatial hot days” and the annual maximum length of “spatial hot spells”. The results indicate a very good correspondence between characteristics derived from synthetic and calibration data. As part of the validation tests, the performance of the WG is compared with a regional climate model (RCM), which shows a similar performance as the generator. In a final experiment, the use of the WG for the future climate is demonstrated, the WG parameters (including the temperature autocorrelations) calibrated with the observed data are modified according to the RCM-based changes in these parameters. While analyzing synthetic series produced with the modified generator, we discuss partial impacts due to changes in individual WG parameters on the spatial hot days and spells. We show that the impacts are mainly (but not only) due to changes in temperature averages. The projected changes in temperature autocorrelations have also some impacts, larger for the spatial hot spells than for the spatial hot days. Climate change impacts on spatial hot days/spells based on the WG are compared with impacts based on the RCM, and we conclude that the differences are mainly due to simplifying assumptions adopted in our pilot experiment. 相似文献
997.
Tianjun Zhou Ziming Chen Liwei Zou Xiaolong Chen Yongqiang Yu Bin Wang Qing Bao Ying Bao Jian Cao Bian He Shuai Hu Lijuan Li Jian Li Yanluan Lin Libin Ma Fangli Qiao Xinyao Rong Zhenya Song Yanli Tang Bo Wu Tongwen Wu Xiaoge Xin He Zhang Minghua Zhang 《Acta Meteorologica Sinica》2020,34(1):1-19
The Earth-Climate System Model (ECSM) is an important platform for multi-disciplinary and multi-sphere integration research, and its development is at the frontier of international geosciences, especially in the field of global change. The research and development (R&D) of ECSM in China began in the 1980s and have achieved great progress. In China, ECSMs are now mainly developed at the Chinese Academy of Sciences, ministries, and universities. Following a brief review of the development history of Chinese ECSMs, this paper summarized the technical characteristics of nine Chinese ECSMs participating in the Coupled Model Intercomparison Project Phase 6 and preliminarily assessed the basic performances of four Chinese models in simulating the global climate and the climate in East Asia. The projected changes of global precipitation and surface air temperature and the associated relationship with the equilibrium climate sensitivity under four shared socioeconomic path scenarios were also discussed. Finally, combined with the international situation, from the perspective of further improvement, eight directions were proposed for the future development of Chinese ECSMs. 相似文献
998.
Sheng Yu Peng Zou Wei Zhu Lin Xiao Aijun Miao Lijuan Jiang Xiaolin Wang Jun Wu Liuyan Yang 《Environmental Earth Sciences》2013,69(5):1523-1528
The effects of organic matter, humic acid and Tween-80 on decabromodiphenyl ether (BDE-209) behavior in soil columns were investigated. The BDE-209 transport was simulated in 4-cm-length soil columns whether organic matter was added or not. A high concentration of BDE-209 was washed out of the soil column in the presence of 500 mg L?1 of Tween-80 for forming and suspending contaminated soil colloids in more than 4-cm-length ones (especially in 10-cm-length ones). While the humic acid was to facilitate BDE-209 adsorption onto soil particles (like soil colloids), Tween-80 was to enhance BDE-209 movement in porous media. The significant concentration averaged from 0.2 to 0.1 μg L?1 in soil columns of length from 10 to 24 cm with Tween-80 addition by comparing the estimated marginal means (p < 0.05, SPSS). Contrasted with humic acid-binding BDE-209 in soil particles, Tween-80 could carry contaminant soil colloids into deeper layers and even affect the final effluents of 25-cm-length columns. It was visibly presented that the BDE-209 concentration in the effluents was mainly induced by Tween-80. Thus, BDE-209 was carried by soil colloids to transport and pollute longer and wider soil distance with the help of the effective promoters and stabilizers of Tween-80 and humic acid in soil matrix. 相似文献
999.
Wenbo Zhou Ping Zou Peishi Sun Xiaoyi Bi Jie Wang Jinquan Chen Haiyu Wang 《Environmental Earth Sciences》2013,70(5):2381-2386
Effects of sodium acetate and glucose on the microbes from the simultaneous flue gas desulfurization and denitrogenation tandem biotrickling process were respectively investigated. For the acidophiles, although the impacts of the carbon sources on the total microbial growth and nitrogen conversion in the medium were slight, the sulfite oxidation rate was obviously improved. The highest sulfite ion oxidation ratio in 48 h was up to 47.2 % as 258.08 mmol L?1 sodium acetate was added in the medium. For the neutrophiles, the two carbons promoted the total microbial growth, but only sodium acetate could enhance the nitrite consumption significantly. The best nitrite consumption rate in 48 h could reach to 86.7 % with 258.08 mmol L?1 sodium acetate. It provides valuable information for the development of biological SO2 and NO x simultaneous purification process. 相似文献
1000.
Weighted fuzzy kernel-clustering algorithm with adaptive differential evolution and its application on flood classification 总被引:1,自引:0,他引:1
Flood classification is the fundamental problem of flood risk analysis and plays an important role in flood disaster risk management. Considering the fact that flood classification is a problem of multi-attribute and multi-stage fuzzy synthetically evaluation, this paper mainly proposed the weighted fuzzy kernel-clustering algorithm (WFKCA) with adaptive differential evolution algorithm (ADE) to solve this problem. Firstly, WFKCA is detailed introduced, and then the differential evolution algorithm (DE) is applied for the fuzzy clustering, thus to obtain the better results. Taking into consideration the disadvantage of DE, ADE is present after the introduction of DE. Finally, the combination of WFKCA and ADE is applied for flood classification, and the results demonstrated the methodology is reasonable and reliable, thus provide a new effective approach for flood classification. 相似文献