依据设计员经验人为确定微电网建设中的容量配比不仅缺乏足够科学依据,易于造成投资浪费,而且还会对后续的经济调度、安全运行等产生负面影响。微电网建设最佳容量配比问题的本质是多目标寻优问题,各电源容量配比与既定指标之间存在复...依据设计员经验人为确定微电网建设中的容量配比不仅缺乏足够科学依据,易于造成投资浪费,而且还会对后续的经济调度、安全运行等产生负面影响。微电网建设最佳容量配比问题的本质是多目标寻优问题,各电源容量配比与既定指标之间存在复杂的非线性关系。为此,本文以某风光柴储互补发电系统设计为牵引,将容易找到全局最优解且寻优速度较快的天牛须搜索算法(bettle antennae search algorithm,BAS)引入到非线性规划性能较好的遗传算法(genetic algorithm,GA)中,在各电源出力模型和既定调度策略基础上,以兰州某点2018年逐时风速、逐时太阳光辐射强度、逐时环境温度为依据,以年供电可靠性最高作为首要目标、投资经济性最好为次要目标,获取最优容量配比方案。算例结果显示,BAS-GA能够给出最优容量配比且具有更快的收敛速度,每次都能得到相同结果,稳定可靠;其BAS-GA结果在负荷缺电率(loss of power supply probability,LPSP)为0.2%的情况下,比0时基本GA数据投资节约66%,也比2.3%时的基本GA结果效费比更高,其他基本GA的结果亦均无法与BAS-GA相比。因此,BAS-GA是微电网建设容量配比优化方案获取中避免基本GA陷入局部最优的有效措施之一。展开更多
Sea surface temperature （SST） proxies including B/Ca, Mg/Ca, St/Ca, U/Ca and δ180 were analyzed in the skeleton of a Porites coral collected from the Zhujiang River （Pearl River） Estuary （ZRE）. These geochemica...Sea surface temperature （SST） proxies including B/Ca, Mg/Ca, St/Ca, U/Ca and δ180 were analyzed in the skeleton of a Porites coral collected from the Zhujiang River （Pearl River） Estuary （ZRE）. These geochemical proxies are influenced by river runoff and this area of the northern South China Sea is strongly affected by seasonal freshwater floods. We assessed the robustness of each SST proxy through comparison with the local instrumental SST. Coral St/Ca shows the highest correlation with SST variations （r2=0.59）, suggesting St/Ca is the most robust SST proxy. In contrast, coral δ180 （r2=0.46）, B/Ca （r2=0.43） and U/Ca （r2=0.41） ratios were only moderately correlated with SST variations, suggesting that they are disturbed by some other factors in addition to SST. The poor correlation （r2=0.27） between SST and Mg/Ca indicates that Mg/Ca in coral skeletons is not a simple function of SST variations. This may ultimately limit the use of Mg/Ca as a coral paleothermometer.展开更多
Rising atmospheric CO2 and warming of the global climate that have occurred since the industrial revolution are regarded as fatal threats to coral reefs. We analyzed the skeletal calcification rate of 14 massive Porit...Rising atmospheric CO2 and warming of the global climate that have occurred since the industrial revolution are regarded as fatal threats to coral reefs. We analyzed the skeletal calcification rate of 14 massive Porites corals from the Meiji Reef in the southern South China Sea through X-ray photography of coral skeletons. A general pattern of change in coral skeletal calcifi- cation was determined. The change pattern of coral calcification on the Meiji Reef over the past two centuries can be divided into five periods： calcification increase in 1770-1830, 1870-1920, and 1980-2000 and calcification decline in 1830-1870 and 1920-1980. Over the past two centuries, the largest increase in calcification was 4.5%, occurring in 1770-1830, whereas the largest decline in calcification was 6.2%, occurring in 1920-1980. Coral calcification slightly increased in the recent 20 years （1980-2000）. The response relationship of coral calcification to atmospheric CO2 and sea surface temperature （SST） shows that calcification was not correlated with atmospheric CO2 but responded nonlinearly to SST with maxima at ~27.2~C in 1900-2000. On the Meiji Reef, increasing atmospheric CO2 had a negligible effect on coral growth in the past century. How- ever, rising SST improved coral growth in the early and middle 20th century, and restricted coral growth in the recent 20 years.展开更多
文摘依据设计员经验人为确定微电网建设中的容量配比不仅缺乏足够科学依据,易于造成投资浪费,而且还会对后续的经济调度、安全运行等产生负面影响。微电网建设最佳容量配比问题的本质是多目标寻优问题,各电源容量配比与既定指标之间存在复杂的非线性关系。为此,本文以某风光柴储互补发电系统设计为牵引,将容易找到全局最优解且寻优速度较快的天牛须搜索算法(bettle antennae search algorithm,BAS)引入到非线性规划性能较好的遗传算法(genetic algorithm,GA)中,在各电源出力模型和既定调度策略基础上,以兰州某点2018年逐时风速、逐时太阳光辐射强度、逐时环境温度为依据,以年供电可靠性最高作为首要目标、投资经济性最好为次要目标,获取最优容量配比方案。算例结果显示,BAS-GA能够给出最优容量配比且具有更快的收敛速度,每次都能得到相同结果,稳定可靠;其BAS-GA结果在负荷缺电率(loss of power supply probability,LPSP)为0.2%的情况下,比0时基本GA数据投资节约66%,也比2.3%时的基本GA结果效费比更高,其他基本GA的结果亦均无法与BAS-GA相比。因此,BAS-GA是微电网建设容量配比优化方案获取中避免基本GA陷入局部最优的有效措施之一。
基金The National Basic Research Program(973 program) of China under contract No.2013CB956104the National Natural Science Foundation of China under contract Nos 41106054,41306109 and 41476038
文摘Sea surface temperature （SST） proxies including B/Ca, Mg/Ca, St/Ca, U/Ca and δ180 were analyzed in the skeleton of a Porites coral collected from the Zhujiang River （Pearl River） Estuary （ZRE）. These geochemical proxies are influenced by river runoff and this area of the northern South China Sea is strongly affected by seasonal freshwater floods. We assessed the robustness of each SST proxy through comparison with the local instrumental SST. Coral St/Ca shows the highest correlation with SST variations （r2=0.59）, suggesting St/Ca is the most robust SST proxy. In contrast, coral δ180 （r2=0.46）, B/Ca （r2=0.43） and U/Ca （r2=0.41） ratios were only moderately correlated with SST variations, suggesting that they are disturbed by some other factors in addition to SST. The poor correlation （r2=0.27） between SST and Mg/Ca indicates that Mg/Ca in coral skeletons is not a simple function of SST variations. This may ultimately limit the use of Mg/Ca as a coral paleothermometer.
基金supported by the National Natural Science Foundation of China (40830852 and 41025007)the Chinese Ministry of Science and Technology Special Scheme (2007CB815905 and 2006BAB19B03)an Australian Research Council Project (DP0773081)
文摘由空至海的 CO2 的领域大小在华南海的三个珊瑚礁石区域交换(即 Nansha 岛的 Yongshu 礁石环礁，南部的华南海(SCS ) ；Xisha 岛的 Yongxing 岛，北方中央的 SCS；并且在海南岛的 Sanya 的 Luhuitou Fringing 礁石，北 SCS ) 在 2008 和 2009 的夏天期间揭示了那 CO2 (pCO2 ) 的部分压力显示出的空气和表面海水常规日报周期。最小的价值在早上发生在晚上和最大的价值。在每三个学习区域的空气 pCO2 出现了小日报变化，当时大日报变化在海水 pCO2 被观察。日报海水 pCO2 的变化振幅是 70 摩尔摩尔? 1 在 Yongshu 礁石泻湖， 420619 摩尔摩尔? 1 在 Yongxing 岛礁石公寓，和 264579 摩尔摩尔上? 1 在 Luhuitou Fringing 礁石的礁石公寓上，并且 324492 摩尔摩尔? 1 在就在这 fringing 礁石外面的一个邻近的区域。关于空间关系，在越过华南海的由空至海的 CO2 流动有大差别(例如 0.4 mmol CO2 m ? 2 d ? 1 在 Yongshu 礁石， 4.7 mmol CO2 m ? 2 d ? 1 在 Yongxing 岛，并且 9.8 mmol CO2 m ? 2 d ? 1 在 Luhuitou Fringing 礁石)。然而，这些积极的值建议 SCS 的珊瑚礁石生态系统可以是到空气的 CO2 的网络来源。另外的分析显示了那日报在浅水礁石公寓的表面海水 pCO2 的变化主要被生物新陈代谢的过程控制，当那些被两个生物新陈代谢和水动力学因素更深的水泻湖和外部礁石区域调整时。不同于开的海洋，无机的新陈代谢在在珊瑚礁石生态系统影响海水 pCO2 变化起一个重要作用。
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA05080300)Important Direction Project of Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No. KZCX2-YW-138)+1 种基金National Natural Science Foundation of China (Grant Nos. 40830852 and 41025007)Chinese Ministry of Science and Technology Projects (Grant Nos. 2007CB8015905 and 2006BAB19B03)
文摘Rising atmospheric CO2 and warming of the global climate that have occurred since the industrial revolution are regarded as fatal threats to coral reefs. We analyzed the skeletal calcification rate of 14 massive Porites corals from the Meiji Reef in the southern South China Sea through X-ray photography of coral skeletons. A general pattern of change in coral skeletal calcifi- cation was determined. The change pattern of coral calcification on the Meiji Reef over the past two centuries can be divided into five periods： calcification increase in 1770-1830, 1870-1920, and 1980-2000 and calcification decline in 1830-1870 and 1920-1980. Over the past two centuries, the largest increase in calcification was 4.5%, occurring in 1770-1830, whereas the largest decline in calcification was 6.2%, occurring in 1920-1980. Coral calcification slightly increased in the recent 20 years （1980-2000）. The response relationship of coral calcification to atmospheric CO2 and sea surface temperature （SST） shows that calcification was not correlated with atmospheric CO2 but responded nonlinearly to SST with maxima at ~27.2~C in 1900-2000. On the Meiji Reef, increasing atmospheric CO2 had a negligible effect on coral growth in the past century. How- ever, rising SST improved coral growth in the early and middle 20th century, and restricted coral growth in the recent 20 years.
