针对红外图像纹理不清晰、亮度低、高噪声的问题,提出了一种自适应多特征融合的红外图像增强算法。首先,通过用自动线性映射的方法对14位红外图像进行有效特征提取得到了16位图像,提升了图像可视化效果。其次,引入广义反锐化掩模(Genera...针对红外图像纹理不清晰、亮度低、高噪声的问题,提出了一种自适应多特征融合的红外图像增强算法。首先,通过用自动线性映射的方法对14位红外图像进行有效特征提取得到了16位图像,提升了图像可视化效果。其次,引入广义反锐化掩模(Generalized Unsharp Masking,GUM)算法与带色彩恢复的多尺度视网膜(Multi-Scale Retinex with Color Restoration,MSRCR)增强算法联合处理的方法,获得图像不同尺度的有效信息,提升了图像的对比度。最后设计了自适应权重图,并结合图像金字塔结构的特性,对不同特征层进行有效信息的互补融合,提升了图像亮度,丰富了图像的纹理信息。实验结果表明,此算法有效提升了红外图像的对比度和视觉效果;相较于现有的几种算法,其平均梯度(Average Gradient,AG)约提升0.6%,峰值信噪比(Peak Signal-to-Noise Ratio,PSNR)约提升10%,图像的边缘信息有效率约提升11%,图像的清晰度约提升10%。展开更多
Wetland soil quality degradation caused by large-scale agricultural reclamation on the Sanjiang Plain of Northeast China has been widely reported. A relative soil quality evaluation (RSQE) model and a projection pursu...Wetland soil quality degradation caused by large-scale agricultural reclamation on the Sanjiang Plain of Northeast China has been widely reported. A relative soil quality evaluation (RSQE) model and a projection pursuit evaluation (PPE) model based on real-coded accelerating genetic algorithm were introduced to evaluate quality variations in top layers of the main wetland soils on the Sanjiang Plain in 1999 and 2003, respectively. As soil quality degradation boundaries were vague, this study established two fuzzy synthetic evaluation (FSE) models based on the original data and criteria used in the RSQE and PPE models. The outputs of the two FSE models were obtained by choosing two fuzzy composite operators M(∧, ∨) and M(·, ⊕). Statistical analysis showed that the results of the FSE, RSQE, and PPE models were correlated. In particular, outputs of the FSE model using M(·, ⊕) were significantly correlated with those of the RSQE model with r = 0.989 at P < 0.01. Compared with RSQE and PPE models, the FSE model may be more objective in showing soil quality variations and was closer to the natural situation, showing the feasibility and applicability of the FSE model in evaluating soil quality degradation. However, the choice of composite operator was of critical importance. The study of wetland soil quality degradation on the Sanjiang Plain was of scientific and practical significance for protection and management of soils and for sustainable development of agriculture in this area in the future.展开更多
Radish (Raphanus sativus L.) is an important vegetable crop worldwide. High nutritional quality was critical in its genetic improvement and production. The nutritional quality of 42 Chinese radish cultivars was anal...Radish (Raphanus sativus L.) is an important vegetable crop worldwide. High nutritional quality was critical in its genetic improvement and production. The nutritional quality of 42 Chinese radish cultivars was analyzed in this study. The contents of six nutritional facts, dry matter (DM), crude fiber (CF), total soluble sugar (TSS), vitamin C (Vc), protein, and nitrate, ranged from 29.7 to 88.2, 4.507 to 18.546, 2.233 to 15.457, 0.1416 to 0.3341, 0.34 to 1.15, and 1.81 to 5.89 g·kg^-1 fresh weight (FW), respectively. Significant differences among the 42 radish cultivars were detected in the contents of nutritional facts. The data were subjected to cross-correlation analysis and principal component analysis (PCA). It was found that DM content was positively correlated with the content of TSS (r=0.7104), Vc (r=0.4011) and protein (r=0.4120). Vitamin C (Vc) content of radish showed a positive correlation (r = 0.3300) with the protein content. According to the principal component analysis, out of the 42 radish cultivars, Nau-17, Nau-28, Nau-6, Nau-11, Nau-10, Nau-27, and Nau-31 were detected with very high scores in comprehensive evaluation. It could be concluded that abundant diversity of nutritional fact content occurred in different radish genotypes, and PCA analysis was effective for selecting radish germplasm with high quality. The results could contribute useful knowledge of nutritional quality, and provide important germplasms for the elite cultivar development and the inheritance study of nutritional facts in radish.展开更多
Water is the most critical factor for controlling die vegetation pattern in arid and semiarid regions.Using a dye-tracing experiment,we analyzed the infiltration pattern beneath shrub canopy and interspace grass patch...Water is the most critical factor for controlling die vegetation pattern in arid and semiarid regions.Using a dye-tracing experiment,we analyzed the infiltration pattern beneath shrub canopy and interspace grass patches in typical steppe ecosystems.The dye coverage,uniform infiltration depth,maximum infiltration depth,total stained area and heterogeneous infiltration stained area were measured by two indices,the maximum infiltration depth index(MIDI)and heterogeneous infiltration index(HII),which were calculated by processing dye-stained photos.The MIDI and HII of soil under shrubs were 1.41±0.14 and 0.29±0.068,respectively,and larger than those of grass soil,1.26±0.14 and0.20±0.076.Using the MIDI,HII,field soil moisture and rainfall data,the infiltration depth and heterogeneous infiltration amount for 26 nature rainfall events were calculated.The results imply that water can infiltrate to a deeper layer beneath shrub canopy than beneath grass patches and that more water infiltration occurs beneath shrub canopy than beneath grass patches.These results are of prime importance for arid and semiarid ecosystems with a limited water supply due to high evaporation and low precipitation.展开更多
文摘针对红外图像纹理不清晰、亮度低、高噪声的问题,提出了一种自适应多特征融合的红外图像增强算法。首先,通过用自动线性映射的方法对14位红外图像进行有效特征提取得到了16位图像,提升了图像可视化效果。其次,引入广义反锐化掩模(Generalized Unsharp Masking,GUM)算法与带色彩恢复的多尺度视网膜(Multi-Scale Retinex with Color Restoration,MSRCR)增强算法联合处理的方法,获得图像不同尺度的有效信息,提升了图像的对比度。最后设计了自适应权重图,并结合图像金字塔结构的特性,对不同特征层进行有效信息的互补融合,提升了图像亮度,丰富了图像的纹理信息。实验结果表明,此算法有效提升了红外图像的对比度和视觉效果;相较于现有的几种算法,其平均梯度(Average Gradient,AG)约提升0.6%,峰值信噪比(Peak Signal-to-Noise Ratio,PSNR)约提升10%,图像的边缘信息有效率约提升11%,图像的清晰度约提升10%。
基金Project supported by the National Natural Science Foundation of China (No. 40830535)the National Key Technology R&D Program of China (No. 2007BAC30B02)the Scientific Program of Department of Education, Hebei Province,China (No. Z2008102)
文摘Wetland soil quality degradation caused by large-scale agricultural reclamation on the Sanjiang Plain of Northeast China has been widely reported. A relative soil quality evaluation (RSQE) model and a projection pursuit evaluation (PPE) model based on real-coded accelerating genetic algorithm were introduced to evaluate quality variations in top layers of the main wetland soils on the Sanjiang Plain in 1999 and 2003, respectively. As soil quality degradation boundaries were vague, this study established two fuzzy synthetic evaluation (FSE) models based on the original data and criteria used in the RSQE and PPE models. The outputs of the two FSE models were obtained by choosing two fuzzy composite operators M(∧, ∨) and M(·, ⊕). Statistical analysis showed that the results of the FSE, RSQE, and PPE models were correlated. In particular, outputs of the FSE model using M(·, ⊕) were significantly correlated with those of the RSQE model with r = 0.989 at P < 0.01. Compared with RSQE and PPE models, the FSE model may be more objective in showing soil quality variations and was closer to the natural situation, showing the feasibility and applicability of the FSE model in evaluating soil quality degradation. However, the choice of composite operator was of critical importance. The study of wetland soil quality degradation on the Sanjiang Plain was of scientific and practical significance for protection and management of soils and for sustainable development of agriculture in this area in the future.
基金grants from the National Natural Science Foundation of China(30571193)the 863 Program of China(2008AA10Z150)+3 种基金the National Key Technologies R&D Program of China(2008BA DB 1B03),the 111 Project from Ministry of Education of China(B08025)the Hi-Tech Key Project of Jiangsu Province(BG2005314)the project of Gene Bank Construction for Brassicaceae Vegetable Germplasm Resources of Jiangsu Province[sx(2007)g13].
文摘Radish (Raphanus sativus L.) is an important vegetable crop worldwide. High nutritional quality was critical in its genetic improvement and production. The nutritional quality of 42 Chinese radish cultivars was analyzed in this study. The contents of six nutritional facts, dry matter (DM), crude fiber (CF), total soluble sugar (TSS), vitamin C (Vc), protein, and nitrate, ranged from 29.7 to 88.2, 4.507 to 18.546, 2.233 to 15.457, 0.1416 to 0.3341, 0.34 to 1.15, and 1.81 to 5.89 g·kg^-1 fresh weight (FW), respectively. Significant differences among the 42 radish cultivars were detected in the contents of nutritional facts. The data were subjected to cross-correlation analysis and principal component analysis (PCA). It was found that DM content was positively correlated with the content of TSS (r=0.7104), Vc (r=0.4011) and protein (r=0.4120). Vitamin C (Vc) content of radish showed a positive correlation (r = 0.3300) with the protein content. According to the principal component analysis, out of the 42 radish cultivars, Nau-17, Nau-28, Nau-6, Nau-11, Nau-10, Nau-27, and Nau-31 were detected with very high scores in comprehensive evaluation. It could be concluded that abundant diversity of nutritional fact content occurred in different radish genotypes, and PCA analysis was effective for selecting radish germplasm with high quality. The results could contribute useful knowledge of nutritional quality, and provide important germplasms for the elite cultivar development and the inheritance study of nutritional facts in radish.
基金National Natural Science Foundation of China (41025001, 41130640 )We would like to thank the anonymous reviewers for their valuable and constructive comments. The authors also wish to thank the Shuai Guan-yuan and Sun Xiu-min for assistance in the field work.
文摘Water is the most critical factor for controlling die vegetation pattern in arid and semiarid regions.Using a dye-tracing experiment,we analyzed the infiltration pattern beneath shrub canopy and interspace grass patches in typical steppe ecosystems.The dye coverage,uniform infiltration depth,maximum infiltration depth,total stained area and heterogeneous infiltration stained area were measured by two indices,the maximum infiltration depth index(MIDI)and heterogeneous infiltration index(HII),which were calculated by processing dye-stained photos.The MIDI and HII of soil under shrubs were 1.41±0.14 and 0.29±0.068,respectively,and larger than those of grass soil,1.26±0.14 and0.20±0.076.Using the MIDI,HII,field soil moisture and rainfall data,the infiltration depth and heterogeneous infiltration amount for 26 nature rainfall events were calculated.The results imply that water can infiltrate to a deeper layer beneath shrub canopy than beneath grass patches and that more water infiltration occurs beneath shrub canopy than beneath grass patches.These results are of prime importance for arid and semiarid ecosystems with a limited water supply due to high evaporation and low precipitation.