In this paper, the marginal Rao-Blackwellized particle filter （MRBPF）, which fuses the Rao-Blackwellized particle filter （RBPF） algorithm and the marginal particle filter （MPF） algorithm, is presented. The state...In this paper, the marginal Rao-Blackwellized particle filter （MRBPF）, which fuses the Rao-Blackwellized particle filter （RBPF） algorithm and the marginal particle filter （MPF） algorithm, is presented. The state space is divided into linear and non-linear parts, which can be estimated separately by the MPF and the optional Kalman filter. Through simulation in the terrain aided navigation （TAN） domain, it is demonstrated that, compared with the RBPF, the root mean square errors （RMSE） and the error variance of the nonlinear state estimations by the proposed MRBPF are respectively reduced by 29% and 96%, while the unique particle count is increased by 80%. It is also found that the MRBPF has better convergence properties, and analysis has shown that the existing RBPF is nothing more than a special case of the MRBPF.展开更多
在马尾松皆伐迹地营造针阔混交林是近年来南方林区松林改造过程中主要的营林实践.许多针阔混交林常面临着季节性干湿交替和地形异质性导致的临时性干旱,这对混交林幼林生长及林下更新均产生较大影响.从水分平衡的角度选择合适的混交树...在马尾松皆伐迹地营造针阔混交林是近年来南方林区松林改造过程中主要的营林实践.许多针阔混交林常面临着季节性干湿交替和地形异质性导致的临时性干旱,这对混交林幼林生长及林下更新均产生较大影响.从水分平衡的角度选择合适的混交树种是成功营造混交林的前提.以杉木和闽北山区常与之混交的木荷、枫香和南酸枣树种为研究对象,通过不同的土壤水分含量梯度设计(CK:正常水分;LD:轻度干旱;MD:中度干旱;SD:重度干旱),从“光合-耗水”的能量同化和水分消耗角度对4个树种进行综合评价.结果表明:(1)在CK条件下,木荷、枫香和南酸枣的日间耗水量可达93.69-111.68 g,最大耗水速率为131.42-177.30 g m^(-2)h^(-1),均显著高于杉木.在CK和LD条件下,杉木的日间耗水量和日间耗水速率较低,而在MD和SD条件下,南酸枣的日间耗水量和日间耗水速率较低.(2)在LD和MD条件下,3种阔叶树种净光合速率(P_(n))下降幅度排序为枫香>南酸枣>木荷,且降幅明显.SD条件下,3种阔叶树种降幅在41.98%-52.05%之间,较为接近.在不同水分条件下,4种苗木的气孔导度(G_(s))与蒸腾速率(T_(r))变化趋势保持一致.在LD和MD条件下枫香和南酸枣水分利用效率(WUE)较高,在SD条件下木荷和杉木WUE更高.在土壤不同水分条件下,木荷光化学效率(F_(v)/F_(m))较其他树种更高,南酸枣F_(v)/F_(m)总体水平较低.(3)光合-耗水能力综合评价结果显示,CK和MD条件下3种阔叶苗木中木荷得分最高,枫香在LD和SD条件评价较好.综上所述,在造林初期,杉木-枫香混交林在阳坡陡坡造林地的适生性相对更强;而在水肥条件较好的缓坡地,杉木-木荷混交林的生产力可能更高.(图2表3参51)展开更多
基金National Natural Science Foundation of China （60572023）
文摘In this paper, the marginal Rao-Blackwellized particle filter （MRBPF）, which fuses the Rao-Blackwellized particle filter （RBPF） algorithm and the marginal particle filter （MPF） algorithm, is presented. The state space is divided into linear and non-linear parts, which can be estimated separately by the MPF and the optional Kalman filter. Through simulation in the terrain aided navigation （TAN） domain, it is demonstrated that, compared with the RBPF, the root mean square errors （RMSE） and the error variance of the nonlinear state estimations by the proposed MRBPF are respectively reduced by 29% and 96%, while the unique particle count is increased by 80%. It is also found that the MRBPF has better convergence properties, and analysis has shown that the existing RBPF is nothing more than a special case of the MRBPF.
文摘在马尾松皆伐迹地营造针阔混交林是近年来南方林区松林改造过程中主要的营林实践.许多针阔混交林常面临着季节性干湿交替和地形异质性导致的临时性干旱,这对混交林幼林生长及林下更新均产生较大影响.从水分平衡的角度选择合适的混交树种是成功营造混交林的前提.以杉木和闽北山区常与之混交的木荷、枫香和南酸枣树种为研究对象,通过不同的土壤水分含量梯度设计(CK:正常水分;LD:轻度干旱;MD:中度干旱;SD:重度干旱),从“光合-耗水”的能量同化和水分消耗角度对4个树种进行综合评价.结果表明:(1)在CK条件下,木荷、枫香和南酸枣的日间耗水量可达93.69-111.68 g,最大耗水速率为131.42-177.30 g m^(-2)h^(-1),均显著高于杉木.在CK和LD条件下,杉木的日间耗水量和日间耗水速率较低,而在MD和SD条件下,南酸枣的日间耗水量和日间耗水速率较低.(2)在LD和MD条件下,3种阔叶树种净光合速率(P_(n))下降幅度排序为枫香>南酸枣>木荷,且降幅明显.SD条件下,3种阔叶树种降幅在41.98%-52.05%之间,较为接近.在不同水分条件下,4种苗木的气孔导度(G_(s))与蒸腾速率(T_(r))变化趋势保持一致.在LD和MD条件下枫香和南酸枣水分利用效率(WUE)较高,在SD条件下木荷和杉木WUE更高.在土壤不同水分条件下,木荷光化学效率(F_(v)/F_(m))较其他树种更高,南酸枣F_(v)/F_(m)总体水平较低.(3)光合-耗水能力综合评价结果显示,CK和MD条件下3种阔叶苗木中木荷得分最高,枫香在LD和SD条件评价较好.综上所述,在造林初期,杉木-枫香混交林在阳坡陡坡造林地的适生性相对更强;而在水肥条件较好的缓坡地,杉木-木荷混交林的生产力可能更高.(图2表3参51)
