Lake Dianchi, one of the main water sources for Kunming, China, experiences severe cyanobacterial blooms due to rapid urbanization and local industrial development. Scientific interest in the mechanisms that cause blooms has been increasing. An integrated model combining rough set theory with binary logistic regression was used to examine the correlation between weather conditions and cyanobacterial blooms in Lake Dianchi based on daily monitoring data. The binary logistic regression yielded quantitative correlations between cyanobacterial blooms and the assessed meteorological variables, including temperature, wind velocity, and wind direction. The rough decision process connected the weather conditions and cyanobacterial blooms, which were used to verify the binary regression model results. It was shown that by comparing the methods, the rough decision-adjusted binary logistic regression model significantly improved model accuracy. The integrated model of cyanobacterial blooms in Lake Dianchi may inform decision-makers at local water purification plants of the water quality in the lake and assist them in making more cost-effective decisions.
<正>什么是MOOC1.概念MOOC是今年教育领域最热的话题,MOOC,Massive Open Online Courses,大规模、开放、在线、课程四个要素缺一不可,构成了MOOC之所以在短时间内能够被采纳被推广的重要因素。Massive,大规模。在上课过程中,人数最多的课有190多个国家的十几万人同时在学,一个学生提出问题,15分钟内肯定有回答,这种没有时差的回应对学生是动机上的激励,这是教学中很重要的一个因素。另外,我们在校内向学生推广网络学习平台时最大的问题是学生缺乏积极性,不爱上论坛发帖子或回复帖子,在MOOC这种大规模的平台上,即使发帖的人比例不大,也足以覆盖观点的维度,这有助于教学目标的完成。
Wang S, Ma S, Zhang L, Wang S, Zhao D, Gao W. Multi layer based rate control algorithm for HEVC, in 2013 IEEE International Symposium on Circuits and Systems (ISCAS2013), Beijing, China, May 19-23, 2013.; 2013:41–44. 访问链接
For sustainable geologic CO2 sequestration (GCS), a better understanding of the effects of brine cation compositions on mica dissolution, surface morphological change, and secondary mineral precipitation under saline hydrothermal conditions is needed. Batch dissolution experiments were conducted with biotite under conditions relevant to GCS sites (55–95 °C and 102 atm CO2). One molar NaCl, 0.4 M MgCl2, or 0.4 M CaCl2 solutions were used to mimic different brine compositions, and deionized water was used for comparison. Faster ion exchange reactions (Na+–K+, Mg2+–K+, and Ca2+–K+) occurred in these salt solutions than in water (H+–K+). The ion exchange reactions affected bump, bulge, and crack formation on the biotite basal plane, as well as the release of biotite framework ions. In these salt solutions, numerous illite fibers precipitated after reaction for only 3 h at 95 °C. Interestingly, in slow illite precipitation processes, oriented aggregation of hexagonal nanoparticles forming the fibrous illite was observed. These results provide new information for understanding scCO2–brine–mica interactions in saline aquifers with different brine cation compositions, which can be useful for GCS as well as other subsurface projects.