根据不同木材表面的光谱反射率差异可以对木材树种进行分类识别。在木制家具及工艺品的生产实践中,考虑到防止木材腐败、开裂,美化木制品外表及延长木制品使用寿命等原因,经常需要在木材表面涂抹某种涂饰。涂抹涂饰将导致木材表面光谱...根据不同木材表面的光谱反射率差异可以对木材树种进行分类识别。在木制家具及工艺品的生产实践中,考虑到防止木材腐败、开裂,美化木制品外表及延长木制品使用寿命等原因,经常需要在木材表面涂抹某种涂饰。涂抹涂饰将导致木材表面光谱反射率曲线产生漂移和变形,经实验验证无法使用原始木材表面的光谱反射率训练出的分类器模型对涂饰木材光谱曲线进行分类识别。相对于原始木材光谱曲线,涂饰木材光谱曲线的漂移和变形可以用非线性模型来拟合;而这种非线性拟合一般使用神经网络来实现。为了能够继续使用原始木材光谱反射率训练的分类器模型,使用全连接神经网络拟合了原始木材光谱反射率和涂饰木材光谱反射率之间的关系模型,通过该模型对涂饰木材光谱反射率进行校正,实现使用原始木材光谱所训练的分类器模型对涂饰木材进行分类识别的目的。此外,还使用卷积神经网络对光谱反射率提取卷积特征,引入表征原始木材光谱反射率和涂饰木材光谱反射率的卷积特征之间关系的隐藏层,将涂饰木材光谱反射率的卷积特征进行校正,并通过输出层输出其分类结果。为了验证所提出的校正模型的有效性,本文以20种木材样本的近红外光谱(950~1650 nm/near infrared spectra,NIR)和可见光/近红外光谱(350~1000 nm/visible and near infrared spectra,VIS/NIR)为研究对象,对比了8种不同涂饰建立的校正模型性能。实验结果表明,NIR的校正分类效果要好于VIS/NIR的校正分类效果;卷积神经网络的校正模型可以将涂抹透明涂饰木材表面的NIR分类正确率提高至70%以上;全连接网络模型可以将涂抹透明涂饰木材表面的NIR分类正确率提高至80%以上,但两种模型都无法对非透明涂饰进行校正。从模型的训练速度和识别效率上看,卷积神经网络的校正模型要好于全连接神经网络的校正模型。综上所述,通过神经网络建立起的原始木材光谱反射率和涂饰木材光谱反射率之间的非线性关系模型,可以对涂抹透明涂饰的木材光谱曲线进行校正。进而实现直接使用原始木材光谱反射率所训练出的分类器模型对涂抹透明涂饰木材光谱曲线进行分类识别,使得木材树种分类识别应用领域从原始木材扩展到涂抹透明涂饰木材,具有较好的实际应用意义和前景。展开更多
The dynamics of soil inorganic nitrogen （NH4^＋ -N and NO3^- -N） and microbial biomass carbon （Cmic） and nitrogen （Nmic） under 30-year-old fenced Pinus sylvestris L. var. mongolica Litvin （SF）, unfenced P. syl...The dynamics of soil inorganic nitrogen （NH4^＋ -N and NO3^- -N） and microbial biomass carbon （Cmic） and nitrogen （Nmic） under 30-year-old fenced Pinus sylvestris L. var. mongolica Litvin （SF）, unfenced P. sylvestris L. var. mongolica Litvin （SUF）, and unfenced Pinus densiflora Siebold et Zucc. （DUF） plantations in the Zhanggutai sandy soil of China were studied during Apr. to Oct. 2004 by the in situ closed-top core incubation method. All mentioned C and N indices in each stand type fluctuated over time. The ranges of inorganic N, Cmic, and Nmic contents in the three stand types were 0.7-2.6, 40.0-128.9, and 5.4-15.2 μg g^-1, respectively. The average contents of soil NH4^＋ -N and Cmic under the three 30-year-old pine plantations were not different. However, soil NO3^ -N and total inorganic N contents decreased in the order of SUF ≥ SF ≥ DUF, the Nmic content was in the order of SF = SUF 〉 DUF, and the Cmic：Nmic ratio was in the order of SUF = DUF 〉 SF. Seasonal variations were observed in soil inorganic N, microbial biomass, and plant growth. These seasonal variations had certain correlations with microbe and plant N use in the soil, and their competition for NH4^＋ -N was mostly regulated by soil N availability. The influence of tree species on inorganic N and Nmic were mainly because of differences in litter quality. Lack of gazing decreased the Cmic：Nmic ratio owing to decreased carbon output and increased the ability of soil to supply N. The soil N supply under the P. sylvestris var. mongolica plantation was lower than under the P. densiflora plantation.展开更多
The effects of soil animals on soil nitrogen (N) mineralization and its availability were studied by investigating soil animal groups and their amounts of macro-faunas sorted by hand, and middle and microfaunas distin...The effects of soil animals on soil nitrogen (N) mineralization and its availability were studied by investigating soil animal groups and their amounts of macro-faunas sorted by hand, and middle and microfaunas distinguished with Tullgren and Baermann methods under three Pinus sylvestris var. mongolica Litv. plantations in Zhanggutai sandy land, China. In addition, soil N mineralization rate was also measured with PVC closed-top tube in situ incubation method. The soil animals collected during growing season belonged to 13 orders, 5 groups, 4 phyla, whose average density was 86 249.17 individuals·m^(-2). There were significant differences in soil animal species, densities, diversities and evenness among three plantations. Permanent grazing resulted in decrease of soil animal species and diversity. The average ammonification, nitrification and mineralization rates were 0.48 g·m^(-2)·a^(-1), 3.68 g·m^(-2)·a^(-1) and 4.16 g·m^(-2)·a^(-1), respectively. The ammonification rate in near-mature forest was higher than that in middle-age forests, while the order of nitrification and net mineralization rates was: middle-age forest without grazing < middle-age forest with grazing < near-mature forest with grazing (P<0.05). Soil N mineralization rate increased with soil animal amounts, but no significant relationship with diversity. The contribution of soil animals to N mineralization was different for different ecosystems due to influences of complex factors including grazing, soil characteristics, the quality and amount of litter on N mineralization.展开更多
Acro-dermato-ungual-lacrimal-tooth syndrome （ADULT syndrome, OMIM 103285） is a rarely seen ectodermal dysplasia disorder first described by Propping and Zerres in 1993. ADULT syndrome is known as an autosomal domina...Acro-dermato-ungual-lacrimal-tooth syndrome （ADULT syndrome, OMIM 103285） is a rarely seen ectodermal dysplasia disorder first described by Propping and Zerres in 1993. ADULT syndrome is known as an autosomal dominant disorder. Only a family constellation and four independent cases were reported worldwide up to now. Here, we report a case of ADULT syndrome, which is the first case reported from China.展开更多
文摘根据不同木材表面的光谱反射率差异可以对木材树种进行分类识别。在木制家具及工艺品的生产实践中,考虑到防止木材腐败、开裂,美化木制品外表及延长木制品使用寿命等原因,经常需要在木材表面涂抹某种涂饰。涂抹涂饰将导致木材表面光谱反射率曲线产生漂移和变形,经实验验证无法使用原始木材表面的光谱反射率训练出的分类器模型对涂饰木材光谱曲线进行分类识别。相对于原始木材光谱曲线,涂饰木材光谱曲线的漂移和变形可以用非线性模型来拟合;而这种非线性拟合一般使用神经网络来实现。为了能够继续使用原始木材光谱反射率训练的分类器模型,使用全连接神经网络拟合了原始木材光谱反射率和涂饰木材光谱反射率之间的关系模型,通过该模型对涂饰木材光谱反射率进行校正,实现使用原始木材光谱所训练的分类器模型对涂饰木材进行分类识别的目的。此外,还使用卷积神经网络对光谱反射率提取卷积特征,引入表征原始木材光谱反射率和涂饰木材光谱反射率的卷积特征之间关系的隐藏层,将涂饰木材光谱反射率的卷积特征进行校正,并通过输出层输出其分类结果。为了验证所提出的校正模型的有效性,本文以20种木材样本的近红外光谱(950~1650 nm/near infrared spectra,NIR)和可见光/近红外光谱(350~1000 nm/visible and near infrared spectra,VIS/NIR)为研究对象,对比了8种不同涂饰建立的校正模型性能。实验结果表明,NIR的校正分类效果要好于VIS/NIR的校正分类效果;卷积神经网络的校正模型可以将涂抹透明涂饰木材表面的NIR分类正确率提高至70%以上;全连接网络模型可以将涂抹透明涂饰木材表面的NIR分类正确率提高至80%以上,但两种模型都无法对非透明涂饰进行校正。从模型的训练速度和识别效率上看,卷积神经网络的校正模型要好于全连接神经网络的校正模型。综上所述,通过神经网络建立起的原始木材光谱反射率和涂饰木材光谱反射率之间的非线性关系模型,可以对涂抹透明涂饰的木材光谱曲线进行校正。进而实现直接使用原始木材光谱反射率所训练出的分类器模型对涂抹透明涂饰木材光谱曲线进行分类识别,使得木材树种分类识别应用领域从原始木材扩展到涂抹透明涂饰木材,具有较好的实际应用意义和前景。
基金the National Key Basic Research Program (973 Program) of China (No. 2007CB106803)the Knowledge Innovation Program of the Chinese Academy of Sciences (No. KZCX1-YW-08-02)the Key Laboratory of Terrestrial Ecological Process and Regional Ecological Safety in Liaoning Province, China (No. 06ZDS212SS).
文摘The dynamics of soil inorganic nitrogen （NH4^＋ -N and NO3^- -N） and microbial biomass carbon （Cmic） and nitrogen （Nmic） under 30-year-old fenced Pinus sylvestris L. var. mongolica Litvin （SF）, unfenced P. sylvestris L. var. mongolica Litvin （SUF）, and unfenced Pinus densiflora Siebold et Zucc. （DUF） plantations in the Zhanggutai sandy soil of China were studied during Apr. to Oct. 2004 by the in situ closed-top core incubation method. All mentioned C and N indices in each stand type fluctuated over time. The ranges of inorganic N, Cmic, and Nmic contents in the three stand types were 0.7-2.6, 40.0-128.9, and 5.4-15.2 μg g^-1, respectively. The average contents of soil NH4^＋ -N and Cmic under the three 30-year-old pine plantations were not different. However, soil NO3^ -N and total inorganic N contents decreased in the order of SUF ≥ SF ≥ DUF, the Nmic content was in the order of SF = SUF 〉 DUF, and the Cmic：Nmic ratio was in the order of SUF = DUF 〉 SF. Seasonal variations were observed in soil inorganic N, microbial biomass, and plant growth. These seasonal variations had certain correlations with microbe and plant N use in the soil, and their competition for NH4^＋ -N was mostly regulated by soil N availability. The influence of tree species on inorganic N and Nmic were mainly because of differences in litter quality. Lack of gazing decreased the Cmic：Nmic ratio owing to decreased carbon output and increased the ability of soil to supply N. The soil N supply under the P. sylvestris var. mongolica plantation was lower than under the P. densiflora plantation.
基金This research was supported by National Natural Science Foundation of China (30471377 & 30600473)the National Programs for Science and Technology Development of China (No. 2005BA517A03).
文摘The effects of soil animals on soil nitrogen (N) mineralization and its availability were studied by investigating soil animal groups and their amounts of macro-faunas sorted by hand, and middle and microfaunas distinguished with Tullgren and Baermann methods under three Pinus sylvestris var. mongolica Litv. plantations in Zhanggutai sandy land, China. In addition, soil N mineralization rate was also measured with PVC closed-top tube in situ incubation method. The soil animals collected during growing season belonged to 13 orders, 5 groups, 4 phyla, whose average density was 86 249.17 individuals·m^(-2). There were significant differences in soil animal species, densities, diversities and evenness among three plantations. Permanent grazing resulted in decrease of soil animal species and diversity. The average ammonification, nitrification and mineralization rates were 0.48 g·m^(-2)·a^(-1), 3.68 g·m^(-2)·a^(-1) and 4.16 g·m^(-2)·a^(-1), respectively. The ammonification rate in near-mature forest was higher than that in middle-age forests, while the order of nitrification and net mineralization rates was: middle-age forest without grazing < middle-age forest with grazing < near-mature forest with grazing (P<0.05). Soil N mineralization rate increased with soil animal amounts, but no significant relationship with diversity. The contribution of soil animals to N mineralization was different for different ecosystems due to influences of complex factors including grazing, soil characteristics, the quality and amount of litter on N mineralization.
基金This study was supported by a grant from Guangdong Natural Science Foundation in 2006(No.06022455).
文摘Acro-dermato-ungual-lacrimal-tooth syndrome （ADULT syndrome, OMIM 103285） is a rarely seen ectodermal dysplasia disorder first described by Propping and Zerres in 1993. ADULT syndrome is known as an autosomal dominant disorder. Only a family constellation and four independent cases were reported worldwide up to now. Here, we report a case of ADULT syndrome, which is the first case reported from China.
