Leaf area is an important parameter for modeling tree growth and physiological processes of trees. The single young and mature leaf area estimation models of eucalyptus were developed based on leaf fresh weight. In to...Leaf area is an important parameter for modeling tree growth and physiological processes of trees. The single young and mature leaf area estimation models of eucalyptus were developed based on leaf fresh weight. In total, leaf area and leaf weight were measured from 455 fresh leaves of 25 trees of eucalyptus in southern China. The majority of the data （80%） were used for model calibration, and the remaining data （20%） were used for model validation. The linear, compound and power models were tested. Based on goodness of fit, prediction ability and residual performance, we found that linear and power models could best describe the relationship between leaf area and weight for young leaf and mature leaf, respectively. The study provides a simple and reliable method for estimating single-leaf area, which has a good potential in the functional- structural model of eucalyptus.展开更多
We present a method to calculate the full gravity gradient tensors from pre-existing vertical gravity data using the cosine transform technique and discuss the calculated tensor accuracy when the gravity anomalies are...We present a method to calculate the full gravity gradient tensors from pre-existing vertical gravity data using the cosine transform technique and discuss the calculated tensor accuracy when the gravity anomalies are contaminated by noise. Gravity gradient tensors computation on 2D infinite horizontal cylinder and 3D ＂Y＂ type dyke models show that the results computed with the DCT technique are more accurate than the FFT technique regardless if the gravity anomalies are contaminated by noise or not. The DCT precision has increased 2 to 3 times from the standard deviation. In application, the gravity gradient tensors of the Hulin basin calculated by DCT and FFT show that the two results are consistent with each other. However, the DCT results are smoother than results computed with FFT. This shows that the proposed method is less affected by noise and can better reflect the fault distribution.展开更多
[Objective] This study aimed to clarify the effects of Pb2＋ and Cr3＋ stress on the contents of chlorophyl in Bryum argenteum and Barbula indica. [Method] B. ar-genteum and B. indica were cultured in different concen...[Objective] This study aimed to clarify the effects of Pb2＋ and Cr3＋ stress on the contents of chlorophyl in Bryum argenteum and Barbula indica. [Method] B. ar-genteum and B. indica were cultured in different concentrations of lead nitrate solu-tion or chromium chloride solution, to investigate the changes in contents of photo-synthetic pigments under lead and chromium single stress. [Result] The results showed that the effects of 1, 10 and 200 mg/L Pb2＋ on B. indica were greater than those on B. argenteum; the effects of 1, 50, 100 and 200 mg/L Cr3＋ on B. argen-teum were greater than those on B. indica. Total chlorophyl content in B. argen-teum and B. indica under different concentrations of Pb2＋ and Cr3＋ was decreased compared with that in control. The tolerance of B. indica to Pb2＋ pol ution was lower than that of B. argenteum, while the tolerance of B. indica to Cr3＋ pol ution was greater than that of B. argenteum. [Conclusion] Based on the conventional require-ments for monitoring materials, B. indica can be used as an indicator species to monitor heavy metal pol ution in the atmosphere of Zhengzhou.展开更多
In practice, airborne gravimetry is a sub-Nyquist sampling method because of the restrictions imposed by national boundaries, financial cost, and database size. In this study, we analyze the sparsity of airborne gravi...In practice, airborne gravimetry is a sub-Nyquist sampling method because of the restrictions imposed by national boundaries, financial cost, and database size. In this study, we analyze the sparsity of airborne gravimetry data by using the discrete Fourier transform and propose a reconstruction method based on the theory of compressed sensing for large- scale gravity anomaly data. Consequently, the reconstruction of the gravity anomaly data is transformed to a Ll-norm convex quadratic programming problem. We combine the preconditioned conjugate gradient algorithm （PCG） and the improved interior-point method （IPM） to solve the convex quadratic programming problem. Furthermore, a flight test was carried out with the homegrown strapdown airborne gravimeter SGA-WZ. Subsequently, we reconstructed the gravity anomaly data of the flight test, and then, we compared the proposed method with the linear interpolation method, which is commonly used in airborne gravimetry. The test results show that the PCG-IPM algorithm can be used to reconstruct large-scale gravity anomaly data with higher accuracy and more effectiveness than the linear interpolation method.展开更多
Many studies have shown that chlorophyll meter readings （CMRs） can be used to diagnose deficiencies of nitrogen （N） during the growth of corn （Zea mays L.） in small-plot trials, but there is need to address addi...Many studies have shown that chlorophyll meter readings （CMRs） can be used to diagnose deficiencies of nitrogen （N） during the growth of corn （Zea mays L.） in small-plot trials, but there is need to address additional problems encountered when diagnoses are made in fields of the size managed in production agriculture. A noteworthy difference between smallplot trials and production agriculture is the extent to which the effects of N are confounded with the effects of other factors such as tillage, landscape, soil organic matter and moisture content. We illustrate how some of these factors can cause differences in the physiological age of plants and introduce errors in the diagnoses of N deficiencies. We suggest methods （measuring the height to the youngest leaf collar and assigning leaf numbers by using the first leaf with pubescence and the ear leaf as references to identify growth stages） for minimizing these errors. The simplified method of growth stage identification can be used to select appropriate plants and leaves for making diagnoses in fields and to distinguish the effects of N from the effects of other factors that influence plant growth.展开更多
This study aimed to optimize the rapid test factors of dry basis weight of reconstituted tobacco, in order to afford a reference test method for companies which produce reconstituted tobacco to better control the basi...This study aimed to optimize the rapid test factors of dry basis weight of reconstituted tobacco, in order to afford a reference test method for companies which produce reconstituted tobacco to better control the basis weight and coating ratio on line. The dry basis weight of reconstituted tobacco was tested by fast method and normal oven method individually. And the effects on the test values of different test factors such as temperature, time and the number of baking sheets were studied. Then the test values of these two methods were compared, so the proper factors of rapid test method were determined. As the baking temperature rose from 130 ℃ to 150 ℃, and the baking time rose from 1 min to 2 min, the difference between fast test method and normal oven method grew, and when the number of baking pieces rose from 3 pieces to 5 pieces, the difference between the two methods went down. The optimum test condition was baking temperature of 130 ℃, baking time of 1 min, and baking sample sheet number of 5. Under this condition, the value of fast test method was the closest to the test value of normal oven method, and meanwhile, the test factor was more proper for testing on line. The study will provide a reference for online controlling of dry basis weight and coating ratio of reconstituted tobacco.展开更多
文摘Leaf area is an important parameter for modeling tree growth and physiological processes of trees. The single young and mature leaf area estimation models of eucalyptus were developed based on leaf fresh weight. In total, leaf area and leaf weight were measured from 455 fresh leaves of 25 trees of eucalyptus in southern China. The majority of the data （80%） were used for model calibration, and the remaining data （20%） were used for model validation. The linear, compound and power models were tested. Based on goodness of fit, prediction ability and residual performance, we found that linear and power models could best describe the relationship between leaf area and weight for young leaf and mature leaf, respectively. The study provides a simple and reliable method for estimating single-leaf area, which has a good potential in the functional- structural model of eucalyptus.
基金supported by the Scientific Research Starting Foundation of HoHai University,China(2084/40801136)the Fundamental Research Funds for the Central Universities(No.2009B12514)
文摘We present a method to calculate the full gravity gradient tensors from pre-existing vertical gravity data using the cosine transform technique and discuss the calculated tensor accuracy when the gravity anomalies are contaminated by noise. Gravity gradient tensors computation on 2D infinite horizontal cylinder and 3D ＂Y＂ type dyke models show that the results computed with the DCT technique are more accurate than the FFT technique regardless if the gravity anomalies are contaminated by noise or not. The DCT precision has increased 2 to 3 times from the standard deviation. In application, the gravity gradient tensors of the Hulin basin calculated by DCT and FFT show that the two results are consistent with each other. However, the DCT results are smoother than results computed with FFT. This shows that the proposed method is less affected by noise and can better reflect the fault distribution.
基金Supported by Science and Technology Supporting Project of Henan Province(132300410358)~~
文摘[Objective] This study aimed to clarify the effects of Pb2＋ and Cr3＋ stress on the contents of chlorophyl in Bryum argenteum and Barbula indica. [Method] B. ar-genteum and B. indica were cultured in different concentrations of lead nitrate solu-tion or chromium chloride solution, to investigate the changes in contents of photo-synthetic pigments under lead and chromium single stress. [Result] The results showed that the effects of 1, 10 and 200 mg/L Pb2＋ on B. indica were greater than those on B. argenteum; the effects of 1, 50, 100 and 200 mg/L Cr3＋ on B. argen-teum were greater than those on B. indica. Total chlorophyl content in B. argen-teum and B. indica under different concentrations of Pb2＋ and Cr3＋ was decreased compared with that in control. The tolerance of B. indica to Pb2＋ pol ution was lower than that of B. argenteum, while the tolerance of B. indica to Cr3＋ pol ution was greater than that of B. argenteum. [Conclusion] Based on the conventional require-ments for monitoring materials, B. indica can be used as an indicator species to monitor heavy metal pol ution in the atmosphere of Zhengzhou.
基金supported by the National High Technology Research and Development Program of China(No.SS2013AA060402)
文摘In practice, airborne gravimetry is a sub-Nyquist sampling method because of the restrictions imposed by national boundaries, financial cost, and database size. In this study, we analyze the sparsity of airborne gravimetry data by using the discrete Fourier transform and propose a reconstruction method based on the theory of compressed sensing for large- scale gravity anomaly data. Consequently, the reconstruction of the gravity anomaly data is transformed to a Ll-norm convex quadratic programming problem. We combine the preconditioned conjugate gradient algorithm （PCG） and the improved interior-point method （IPM） to solve the convex quadratic programming problem. Furthermore, a flight test was carried out with the homegrown strapdown airborne gravimeter SGA-WZ. Subsequently, we reconstructed the gravity anomaly data of the flight test, and then, we compared the proposed method with the linear interpolation method, which is commonly used in airborne gravimetry. The test results show that the PCG-IPM algorithm can be used to reconstruct large-scale gravity anomaly data with higher accuracy and more effectiveness than the linear interpolation method.
基金the Iowa Soybean Association, USA through the ISA On-Farm NetworkTM and Watershed Programming.
文摘Many studies have shown that chlorophyll meter readings （CMRs） can be used to diagnose deficiencies of nitrogen （N） during the growth of corn （Zea mays L.） in small-plot trials, but there is need to address additional problems encountered when diagnoses are made in fields of the size managed in production agriculture. A noteworthy difference between smallplot trials and production agriculture is the extent to which the effects of N are confounded with the effects of other factors such as tillage, landscape, soil organic matter and moisture content. We illustrate how some of these factors can cause differences in the physiological age of plants and introduce errors in the diagnoses of N deficiencies. We suggest methods （measuring the height to the youngest leaf collar and assigning leaf numbers by using the first leaf with pubescence and the ear leaf as references to identify growth stages） for minimizing these errors. The simplified method of growth stage identification can be used to select appropriate plants and leaves for making diagnoses in fields and to distinguish the effects of N from the effects of other factors that influence plant growth.
基金Supported by Science and Technology Planning Project of China Tobacco Schweitzer(Yunnan)Reconstituted Tobacco Co.,Ltd.(KY-17-ZL-01)China Tobacco Yunnan Industrial Co.,Ltd.(2016YL02)
文摘This study aimed to optimize the rapid test factors of dry basis weight of reconstituted tobacco, in order to afford a reference test method for companies which produce reconstituted tobacco to better control the basis weight and coating ratio on line. The dry basis weight of reconstituted tobacco was tested by fast method and normal oven method individually. And the effects on the test values of different test factors such as temperature, time and the number of baking sheets were studied. Then the test values of these two methods were compared, so the proper factors of rapid test method were determined. As the baking temperature rose from 130 ℃ to 150 ℃, and the baking time rose from 1 min to 2 min, the difference between fast test method and normal oven method grew, and when the number of baking pieces rose from 3 pieces to 5 pieces, the difference between the two methods went down. The optimum test condition was baking temperature of 130 ℃, baking time of 1 min, and baking sample sheet number of 5. Under this condition, the value of fast test method was the closest to the test value of normal oven method, and meanwhile, the test factor was more proper for testing on line. The study will provide a reference for online controlling of dry basis weight and coating ratio of reconstituted tobacco.
