In this work,the impact of hop constraints on the CAPEX of multi-layer IP/MPLS over WSON networks is evaluated under different scenarios. By routing lightpaths with different number of transparent hops,the cost of net...In this work,the impact of hop constraints on the CAPEX of multi-layer IP/MPLS over WSON networks is evaluated under different scenarios. By routing lightpaths with different number of transparent hops,the cost of networks varies significantly. This effect is thoroughly analyzed with a heuristic algorithm for different network topologies belonging to some European network operators. The main conclusion extracted is that limiting the transparent reach in such multi-layer networks can give a good tradeoff between CAPEX of IP/MPLS networks and WSON networks,and even lead to signifi cant savings in CAPEX when compared to longer lightpaths routing strategies.展开更多
含氮化合物是大气细颗粒物(PM_(2.5))的重要组分,其中含氮有机物是含氮组分的重要存在形式,对陆地和水生生态系统影响较大.于2015年4月、7月和10月分别采集了金华市3个具有代表性站点的PM_(2.5)样品,分析了其中水溶性有机氮(water-solub...含氮化合物是大气细颗粒物(PM_(2.5))的重要组分,其中含氮有机物是含氮组分的重要存在形式,对陆地和水生生态系统影响较大.于2015年4月、7月和10月分别采集了金华市3个具有代表性站点的PM_(2.5)样品,分析了其中水溶性有机氮(water-soluble organic nitrogen,WSON)的质量浓度分布及季节变化特征.结果表明:金华市PM2.5中WSON质量浓度范围为0.06~6.90μg/m^3,平均1.90μg/m^3,对水溶性总氮(water-soluble total nitrogen,WSTN)的平均贡献率为31%.WSON的质量浓度分布具有明显的季节变化特征:秋季较高,夏季较低,而在夏季WSON对WSTN的贡献率最高.金华市PM_(2.5)中WSON的主要来源可能是含氮前体物在大气中的二次转化以及生物质燃烧活动.展开更多
森林生态系统作为生物圈的重要组成部分,维持着全球植被碳库的86%和土壤碳库的40%(Houghton et al.,2001;胡会峰等,2006)。因此,森林在调节全球气候、维持全球碳平衡方面起着非常重要的作用(Fang et al.,2001;Woodbury et al.,2007;H...森林生态系统作为生物圈的重要组成部分,维持着全球植被碳库的86%和土壤碳库的40%(Houghton et al.,2001;胡会峰等,2006)。因此,森林在调节全球气候、维持全球碳平衡方面起着非常重要的作用(Fang et al.,2001;Woodbury et al.,2007;Hu et al.,2008)。然而,展开更多
In order to investigate effect of fertilization on water-soluble organic N (WSON) in the soils under chestnut stands,a fertilization experiment was carried out in Lin-an county in Zhejiang province. The results of thi...In order to investigate effect of fertilization on water-soluble organic N (WSON) in the soils under chestnut stands,a fertilization experiment was carried out in Lin-an county in Zhejiang province. The results of this study showed that fertilization increased WSON in the soils under chestnut stands. Excessive chemical fertilizer addition or combined application of chemical fertilizers and organic manure had most strong effects by increasing the concentrations of WSON in the soils respectively by 5.68 and 1.94 times,compared with the unfertilized control,There was no difference in WSON concentrations in the soils among the treatments with routine chemical fertilizer rate,organic manure alone and unfertilized control. Excessive fertilizer application induced the highest ratio of WSON/total N (5.76%),which was markedly greater than that done by other three treatments. The ratio of WSON/hydrolyzed N ranged from 9.34% to 37.04% with average value of 26.78%. The highest ratio of hydrolyzed N/total N (37.04%) was found from the treatments of excessive fertilizer application and the ratio was markedly greater than that of other three treatments. The correlation analysis showed that there were significant correlations between WSON and soil total N,hydrolyzed N,water soluble total N,water soluble NH4+-N or water soluble NO3-N. The corresponding correlation coefficients were 0.565 1,0.918 6,0.998 6,0.9939 and 0.5401,respectively.展开更多
基金jointly supported by Jiangsu Government Scholarship for Overseas studies,Chinathe open fund of State Key Laboratory of Advanced Optical Communication Systems and Networks, Shanghai Jiao Tong University,China(No. 2015GZKF03006)Research Center of Optical Communications Engineering & Technology,Jiangsu Province(No.ZSF0201)
文摘In this work,the impact of hop constraints on the CAPEX of multi-layer IP/MPLS over WSON networks is evaluated under different scenarios. By routing lightpaths with different number of transparent hops,the cost of networks varies significantly. This effect is thoroughly analyzed with a heuristic algorithm for different network topologies belonging to some European network operators. The main conclusion extracted is that limiting the transparent reach in such multi-layer networks can give a good tradeoff between CAPEX of IP/MPLS networks and WSON networks,and even lead to signifi cant savings in CAPEX when compared to longer lightpaths routing strategies.
文摘含氮化合物是大气细颗粒物(PM_(2.5))的重要组分,其中含氮有机物是含氮组分的重要存在形式,对陆地和水生生态系统影响较大.于2015年4月、7月和10月分别采集了金华市3个具有代表性站点的PM_(2.5)样品,分析了其中水溶性有机氮(water-soluble organic nitrogen,WSON)的质量浓度分布及季节变化特征.结果表明:金华市PM2.5中WSON质量浓度范围为0.06~6.90μg/m^3,平均1.90μg/m^3,对水溶性总氮(water-soluble total nitrogen,WSTN)的平均贡献率为31%.WSON的质量浓度分布具有明显的季节变化特征:秋季较高,夏季较低,而在夏季WSON对WSTN的贡献率最高.金华市PM_(2.5)中WSON的主要来源可能是含氮前体物在大气中的二次转化以及生物质燃烧活动.
文摘森林生态系统作为生物圈的重要组成部分,维持着全球植被碳库的86%和土壤碳库的40%(Houghton et al.,2001;胡会峰等,2006)。因此,森林在调节全球气候、维持全球碳平衡方面起着非常重要的作用(Fang et al.,2001;Woodbury et al.,2007;Hu et al.,2008)。然而,
文摘In order to investigate effect of fertilization on water-soluble organic N (WSON) in the soils under chestnut stands,a fertilization experiment was carried out in Lin-an county in Zhejiang province. The results of this study showed that fertilization increased WSON in the soils under chestnut stands. Excessive chemical fertilizer addition or combined application of chemical fertilizers and organic manure had most strong effects by increasing the concentrations of WSON in the soils respectively by 5.68 and 1.94 times,compared with the unfertilized control,There was no difference in WSON concentrations in the soils among the treatments with routine chemical fertilizer rate,organic manure alone and unfertilized control. Excessive fertilizer application induced the highest ratio of WSON/total N (5.76%),which was markedly greater than that done by other three treatments. The ratio of WSON/hydrolyzed N ranged from 9.34% to 37.04% with average value of 26.78%. The highest ratio of hydrolyzed N/total N (37.04%) was found from the treatments of excessive fertilizer application and the ratio was markedly greater than that of other three treatments. The correlation analysis showed that there were significant correlations between WSON and soil total N,hydrolyzed N,water soluble total N,water soluble NH4+-N or water soluble NO3-N. The corresponding correlation coefficients were 0.565 1,0.918 6,0.998 6,0.9939 and 0.5401,respectively.