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The Effects of Dwarfing Genes (Rht-B1b, Rht-D1b, and Rht8) with Different Sensitivity to GA_3 on the Coleoptile Length and Plant Height of Wheat 被引量:14
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作者 TANG Na JIANG Ying +1 位作者 HE Bei-ru HU Yin-gang 《Agricultural Sciences in China》 CAS CSCD 2009年第9期1028-1038,共11页
Understanding the effects of wheat dwarfing genes on the coleoptile length and plant height is crucial for the proper utilization of dwarfing genes in the improvement of wheat yield. Molecular marker analysis combined... Understanding the effects of wheat dwarfing genes on the coleoptile length and plant height is crucial for the proper utilization of dwarfing genes in the improvement of wheat yield. Molecular marker analysis combined with pedigree information were used to classify wheat cultivars widely planted in major wheat growing regions in China into different categories based on the dwarfing genes they carried. The effects of the dwarfing genes with different sensitivity to gibberellins (GA3) on the coleoptile length and plant height were analyzed. Screening of 129 cultivars by molecular marker analysis revealed that 58 genotypes of wheat contained the dwarfing gene Rht-B1b, 24 genotypes of wheat contained Rht-D1b gene and 73 genotypes of wheat possessed Rht8 gene. In addition, among these 129 cultivars, 35 genotypes of wheat cultivars contained both Rht-B1b and Rht8 genes and 16 genotypes of wheat cultivars contained both Rht-D1b and Rht8 genes. Wheat cultivars with the dwarfing genes Rht-B1b or Rht-D1b were insensitive to GA3, while the cultivars with the dwarfing gene Rht8 were sensitive to GA3. Most of the wheat genotypes containing combination of Rht8 gene with either Rht-B1b or Rht-D1b gene were insensitive to GA3. The plant height was reduced by 24.6, 30.4, 28.2, and 32.2%, respectively, for the wheat cultivars containing Rht-B1b, Rht-D1b, Rht-B1b + Rht8, and Rht-D1b + Rht8 genes. The plant height was reduced by 14.3% for the wheat cultivar containing GA3-sensitive gene Rht8. The coleoptile length was shortened by 25.4, 31.3, 28.4 and 31.3%, respectively, in the wheat cultivars containing Rht-B1b, Rht-D1b, Rht-B1b +Rht8 and Rht-D1b + Rht8 genes, while the coleoptile length was shortened only by 6.2% for the wheat cultivar containing Rht8 gene. We conclude that GA3-insensitive dwarfing genes (Rht-B1b and Rht-D1b) are not suitable for the wheat improvement in dryland because these two genes have effect on reducing both plant height and coleoptile length. In contrast, GA3- sensitive dwarfing gene (Rht8) is a relatively ideal candidate for the wheat improvement since it significantly reduces the plant height of wheat, but has less effect on the coleoptile length. 展开更多
关键词 bread wheat dwarfing genes Rht-B1b Rht-D1b Rht8 coleoptile length plant height
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Nonlinear mixed-effects height to crown base and crown length dynamic models using the branch mortality technique for a Korean larch( Larix olgensis ) plantations in northeast China 被引量:8
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作者 Weiwei Jia Dongsheng Chen 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第6期2095-2109,共15页
Korean larch(Larix olgensis)is one of the main tree species for aff orestation and timber production in northeast China.However,its timber quality and growth ability are largely infl uenced by crown size,structure and... Korean larch(Larix olgensis)is one of the main tree species for aff orestation and timber production in northeast China.However,its timber quality and growth ability are largely infl uenced by crown size,structure and shape.The majority of crown models are static models based on tree size and stand characteristics from temporary sample plots,but crown dynamic models has seldom been constructed.Therefore,this study aimed to develop height to crown base(HCB)and crown length(CL)dynamic models using the branch mortality technique for a Korean larch plantation.The nonlinear mixed-eff ects model with random eff ects,variance functions and correlation structures,was used to build HCB and CL dynamic models.The data were obtained from 95 sample trees of 19 plots in Meng JiaGang forest farm in Northeast China.The results showed that HCB progressively increases as tree age,tree height growth(HT growth)and diameter at breast height growth(DBH growth).The CL was increased with tree age in 20 years ago,and subsequently stabilized.HT growth,DBH growth stand basal area(BAS)and crown competition factor(CCF)signifi cantly infl uenced HCB and CL.The HCB was positively correlated with BAS,HT growth and DBH growth,but negatively correlated with CCF.The CL was positively correlated with BAS and CCF,but negatively correlated with DBH growth.Model fi tting and validation confi rmed that the mixed-eff ects model considering the stand and tree level random eff ects was accurate and reliable for predicting the HCB and CL dynamics.However,the models involving adding variance functions and time series correlation structure could not completely remove heterogeneity and autocorrelation,and the fi tting precision of the models was reduced.Therefore,from the point of view of application,we should take care to avoid setting up over-complex models.The HCB and CL dynamic models in our study may also be incorporated into stand growth and yield model systems in China. 展开更多
关键词 Larix olgensis plantation height to CROWN BASE CROWN length Branch MORTALITY technique NONLINEAR mixed-eff ects models
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Robust state-space realizations of digital filters against finite word length errors 被引量:3
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作者 He Xiongxiong Li Gang +1 位作者 Zhu Guangxin Wan Chunru 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第5期896-901,共6页
This article deals with two important issues in digital filter implementation: roundoff noise and limit cycles. A novel class of robust state-space realizations, called normal realizations, is derived and characteriz... This article deals with two important issues in digital filter implementation: roundoff noise and limit cycles. A novel class of robust state-space realizations, called normal realizations, is derived and characterized. It is seen that these realizations are free of limit cycles. Another interesting property of the normal realizations is that they yield a minimal error propagation gain. The optimal realization problem, defined as to find those normal realizations that minimize roundoff noise gain, is formulated and solved analytically. A design example is presented to demonstrate the behavior of the optimal normal realizations and to compare them with several well-known digital filter realizations in terms of minimizing the roundoff noise and the error propagation. 展开更多
关键词 digital signal processing digital filter structures optimal normal realizations finite word length roundoff noise limit cycles.
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Uncertainty of Slope Length Derived from Digital Elevation Models of the Loess Plateau, China 被引量:8
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作者 ZHU Shi-jie TANG Guo-an +1 位作者 XIONG Li-yang ZHANG Gang 《Journal of Mountain Science》 SCIE CSCD 2014年第5期1169-1181,共13页
Although many studies have investigated slope gradient uncertainty derived from Digital Elevation Models(DEMs), the research concerning slope length uncertainty is far from mature. This discrepancy affects the availab... Although many studies have investigated slope gradient uncertainty derived from Digital Elevation Models(DEMs), the research concerning slope length uncertainty is far from mature. This discrepancy affects the availability and accuracy of soil erosion as well as hydrological modeling. This study investigates the formation and distribution of existing errors and uncertainties in slope length derivation based on 5-m resolution DEMs of the Loess Plateau in the middle of China. The slope length accuracy in three different landform areas is examined to analyse algorithm effects. The experiments indicate that the accuracy of the flat test area is lower than that of the rougher areas. The value from the specific contributing area(SCA) method is greater than the cumulative slope length(CSL), and the differences between these two methods arise from the shape of the upslope area. The variation of mean slope length derived from various DEM resolutions and landforms. The slope length accuracy decreases with increasing grid size and terrain complexity at the six test sites. A regression model is built to express the relationship of mean slope length with DEM resolution less than 85 m and terrain complexity represented by gully density. The results support the understanding of the slope length accuracy, thereby aiding in the effective evaluation of the modeling effect of surface process. 展开更多
关键词 Slope length Uncertainty digital Elevation Models(DEM) Loess terrain
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Research on the arc length and droplet transition control strategy for the full digital pulse MIG welding power supply
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作者 段彬 张承慧 +2 位作者 张光先 孙同景 王海全 《China Welding》 EI CAS 2012年第4期38-42,共5页
Arc length stability and droplet transition consistency are key factors for the pulse metal inert gas (MIG) welding quality. A new control strategy is proposed based on pulse current waveform adjustment to stabilize... Arc length stability and droplet transition consistency are key factors for the pulse metal inert gas (MIG) welding quality. A new control strategy is proposed based on pulse current waveform adjustment to stabilize the welding process. After sufficient analysis of the droplet transition process, key current waveform parameters are refined that can affect the welding quality greatly. In order to achieve the optimal nonlinear control of parameters, the fuzzy controller is designed successfully with two inputs and three outputs in field programmable gate array ( FPGA ), which occupies fewer resources than PID controller and has higher control performance. Experimental results show that the arc length can be adjusted fast in full range of welding current, the welding process is stable, the droplet transition has good consistency, and the welding quality is perfect. 展开更多
关键词 full digital arc length stability droplet transition fuzzy controller
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Evaluating the Impacts of Using Different Digital Surface Models to Estimate Forest Height with TanDEM-X Interferometric Coherence Data
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作者 CHEN Hao HILL David A. +1 位作者 WHITE Joanne C. CLOUDE Shane R. 《雷达学报(中英文)》 CSCD 北大核心 2020年第2期386-398,共13页
In our previous studies, we demonstrated the usefulness of TanDEM-X interferometric bistatic mode with single polarization to obtain forest heights for the purposes of large area mapping. A key feature of our approach... In our previous studies, we demonstrated the usefulness of TanDEM-X interferometric bistatic mode with single polarization to obtain forest heights for the purposes of large area mapping. A key feature of our approach has been the use of a simplified Random Volume Over Ground(RVOG) model that locally estimates forest height. The model takes TanDEM-X interferometric coherence amplitude as an input and uses an external Digital Surface Model(DSM) to account for local slope variations due to terrain topography in order to achieve accurate forest height estimation. The selection of DSM for use as a local slope reference is essential, as an inaccurate DSM will result in less accurate terrain-correction and forest height estimation. In this paper, we assessed TanDEM-X height estimates associated with scale variations in different DSMs used in the model over a remote sensing supersite in Petawawa, Canada. The DSMs used for assessments and comparisons included ASTER GDEM, ALOS GDSM, airborne DRAPE DSM, Canadian DSM and TanDEM-X DSM. Airborne Laser Scanning(ALS) data were used as reference for terrain slope and forest height comparisons. The results showed that, with the exception of the ASTER GDEM, all DSMs were sufficiently accurate for the simplified RVOG model to provide a satisfactory estimate of stand-level forest height. When compared to the ALS 95th height percentile, the modeled forest heights had R2 values greater than 80% and Root-Mean-Square Errors(RMSE)less than 2 m. For a close similarity in slope estimation with the ALS reference, coverage across Canada and open data access, the 0.75 arc-second(20 m) resolution Canadian DSM was selected as a preferred choice for the simplified RVOG model to provide TanDEM-X height estimation in Canada. 展开更多
关键词 INTERFEROMETRIC COA digital surface model FOREST height
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New expressions for the surface roughness length and displacement height in the atmospheric boundary layer
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作者 林建忠 李惠君 张凯 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第7期2033-2039,共7页
An alternative model for the prediction of surface roughness length is developed. In the model a new factor is introduced to compensate for the effects of wake diffusion and interactions between the wake and roughness... An alternative model for the prediction of surface roughness length is developed. In the model a new factor is introduced to compensate for the effects of wake diffusion and interactions between the wake and roughness obstacles. The experiments are carried out by the use of the hot wire anemometry in the simulated atmospheric boundary layer in a wind tunnel. Based on the experimental data, a new expression for the zero-plane displacement height is proposed for the square arrays of roughness elements, which highlights the influence of free-stream speed on the roughness length. It appears that the displacement height increases with the wind speed while the surface roughness length decreases with Reynolds number increasing. It is shown that the calculation results based on the new expressions are in reasonable agreement with the experimental data. 展开更多
关键词 roughness length zero-plane displacement height atmospheric boundary layer free stream speed packing density
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Optimization of block-floating-point realizations for digital controllers with finite-word-length considerations
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作者 吴俊 胡协和 +1 位作者 陈生 褚健 《Journal of Zhejiang University Science》 EI CSCD 2003年第6期651-657,共7页
The closed-loop stability issue of finite-precision realizations was investigated for digital control-lers implemented in block-floating-point format. The controller coefficient perturbation was analyzed resultingfrom... The closed-loop stability issue of finite-precision realizations was investigated for digital control-lers implemented in block-floating-point format. The controller coefficient perturbation was analyzed resultingfrom using finite word length (FWL) block-floating-point representation scheme. A block-floating-point FWL closed-loop stability measure was derived which considers both the dynamic range and precision. To facilitate the design of optimal finite-precision controller realizations, a computationally tractable block-floating-point FWL closed-loop stability measure was then introduced and the method of computing the value of this measure for a given controller realization was developed. The optimal controller realization is defined as the solution that maximizes the corresponding measure, and a numerical optimization approach was adopted to solve the resulting optimal realization problem. A numerical example was used to illustrate the design procedure and to compare the optimal controller realization with the initial realization. 展开更多
关键词 digital controller Finite word length Block floating point Closed loop stability OPTIMIZATION
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Longitudinal Relationship between Axial Length and Height in Chinese Children:Guangzhou Twin Eye Study
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作者 Decai Wang Chen Zhao +2 位作者 Shengsong Huang Wenyong Huang Mingguang He 《眼科学报(英文版)》 CAS 2015年第1期1-6,12,共7页
Purpose:.To understand the growth model of axial length(AL) and height, and to explore the relationship between the two with the passage of time.Methods:.We followed twins in the Guangzhou Twin Eye Study for five year... Purpose:.To understand the growth model of axial length(AL) and height, and to explore the relationship between the two with the passage of time.Methods:.We followed twins in the Guangzhou Twin Eye Study for five years..The AL of both eyes was measured by partial coherence interferometry, and height was measured by a standard scale during each visit..A multivariate multilevel mixed model was adopted for data analysis.Results:.A total of 1217 children were included in the study.Both AL and height increased, but the rate of growth slowed down with age..The mitigation rate of height growth was-0.34 cm / year;.while that of AL growth was-0.01 mm / year.AL was positively related to height,.with a relevant coefficient of R=0.22(Cov [height intercept, AL intercept] =1.56, 95%CI=1.14 to 1.99). The growth rates of AL and height were also positively related, with a relevant coefficient of R =0.18(Cov [height slope, AL slope] =0.03, 95%CI=0.01 to 0.05).However, taller children had slower rates of height increases,with a relevant coefficient of R=-0.12(Cov[height intercept,height slope]=-1.33,95%CI=-2.25 to-0.42); but had faster AL growth,.with a relevant coefficient of R =(Cov [height intercept, AL slope] =0.02, 95%CI=-0.05 to 0.08, R=0.02).AL and its growth rate were positively related to each other,with a relevant coefficient of R=(Cov [AL intercept,.AL slope]=0.04, 95%CI=0.03 to 0.05, R=0.3); while the growth rates of AL and height were negatively related to each other, with a relevant coefficient of R=(Cov [AL intercept, height slope]=--0.03 95%CI=-0.16 to 0.1, R=-0.02).Conclusion:.The increase in children's AL is relevant to their height increases..The faster their height increases,.the faster their AL increases. 展开更多
关键词 轴向长度 儿童 科研 广州 相关系数 冠状病毒 拦截高度 中国
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Finite element analysis on the collapse of infill walls with holes and different length-to-height ratios
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作者 周晓方 叶燕华 +1 位作者 SUN Rui YIN Wan-qing 《Journal of Chongqing University》 CAS 2013年第4期155-162,共8页
Wenchuan earthquake damage survey displayed the major structures of buildings suffered only small damages,but it was common that infill walls suffered heavy damages or even collapse. To study the failure forms and col... Wenchuan earthquake damage survey displayed the major structures of buildings suffered only small damages,but it was common that infill walls suffered heavy damages or even collapse. To study the failure forms and collapse mechanism of infill walls in an earthquake,the influence of opening or length-to-height ratio on shake-resisting capability of filling walls was analyzed,and measures to improve the anti-collapse ability of infill walls were put forwaed. The numerical simulations on collapse process in earthquake were carried out by using ABAQUS software. We used 5 single story and single span models. It is revealed that the rigidity and compressive capacity of infill walls are reduced because of the infill walls with holes and the increases of length-to-height ratios. Adding constructional columns and horizontal beams can ensure structural integrity and improve the anti-collapse ability of the wall. 展开更多
关键词 finite element analysis COLLAPSE length-height ratio RIGIDITY
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Second to fourth digit ratio: a predictor of adult penile ength 被引量:3
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作者 In Ho Choi Khae Hawn Kim +3 位作者 Han Jung Sang Jin Yoon Soo Woong Kim Tae Beom Kim 《Asian Journal of Andrology》 SCIE CAS CSCD 2011年第5期710-714,共5页
The second to fourth digit ratio (2D:4D) has been proposed as a putative biomarker for prenatal testosterone and covaries with the sensitivity of the androgen receptor (AR). Both prenatal testosterone and the AR ... The second to fourth digit ratio (2D:4D) has been proposed as a putative biomarker for prenatal testosterone and covaries with the sensitivity of the androgen receptor (AR). Both prenatal testosterone and the AR play a central role in penile growth. In this study, we investigated the relationship between digit ratio and penile length. Korean men who were hospitalized for urological surgery at a single tertiary academic centre were examined in this study, and 144 men aged 20 years or older who gave informed consent were prospectively enrolled. Right-hand second- and fourth-digit lengths were measured by a single investigator prior to measurement of penile length. Under anaesthesia, flaccid and stretched penile lengths were measured by another investigator who did not measure nor have any the information regarding the digit lengths. Univariate and multivariate analysis using linear regression models showed that only height was a significant predictive factor for flaccid penile length (univariate analysis: r=0. 185, P=-0.026; multivariate analysis: r=-0.172, P=0.038) and that only digit ratio was a significant predictive factor for stretched penile length (univariate analysis: r=-0.216, P=0.009; multivariate analysis: r=-0.201, P=0.024; stretched penile length=-9.201 xdigit ratio + 20.577). Based on this evidence, we suggest that the digit ratio can predict adult penile size and that the effects of prenatal testosterone may in part explain the differences in adult penile length. 展开更多
关键词 digit ratio flaccid penile length stretched penile length
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Kolmogorov-Chaitin Complexity of Digital Controller Implementations 被引量:1
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作者 James F. Whidborne John McKernan Da-Wei Gu 《International Journal of Automation and computing》 EI 2006年第3期314-322,共9页
The complexity of linear, fixed-point arithmetic digital controllers is investigated from a Kolmogorov-Chaitin perspective. Based on the idea of Kolmogorov-Chaitin complexity, practical measures of complexity are deve... The complexity of linear, fixed-point arithmetic digital controllers is investigated from a Kolmogorov-Chaitin perspective. Based on the idea of Kolmogorov-Chaitin complexity, practical measures of complexity are developed for statespace realizations, parallel and cascade realizations, and for a newly proposed generalized implicit state-space realization. The complexity of solutions to a restricted complexity controller benchmark problem is investigated using this measure. The results show that from a Kolmogorov-Chaitin viewpoint, higher-order controllers with a shorter word-length may have lower complexity and better performance, than lower-order controllers with longer word-length. 展开更多
关键词 Controller complexity finite-precision arithmetic finite word length digital controller Kolmogorov-Chaitin complexity.
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Improving advantages and reducing risks in increasing cyclone height via an apex cone to grasp vortex end 被引量:1
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作者 Ronghua Zhang Jingxuan Yang +2 位作者 Shaoxing Han Xiaogang Hao Guoqing Guan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期136-143,共8页
For a cyclone, it is possible to improve separation efficiency and reduce pressure drop by increasing the cyclone height. However, an exceeded height increase could result in a dramatical drop in separation efficiency... For a cyclone, it is possible to improve separation efficiency and reduce pressure drop by increasing the cyclone height. However, an exceeded height increase could result in a dramatical drop in separation efficiency. In this study, experimental and computational fluid dynamics simulation results exhibit that the introduction of an apex cone at the dust outlet could avoid the risk of separation efficiency drop but lead to a continuous reducing of the pressure drop. Generally, the optimal cyclone height should be closely related to the natural vortex length. While, when the vortex end contracts into the separation space in the cyclone with an exceeded height, severe back-mixing of particles always occurs, which will result in the decrease of separation efficiency. Herein, it is found that when an apex cone is installed at the dust outlet, the vortex end can be grasped by the cone so as to weaken the back-mixing of particles.Meanwhile, the introduction of this apex cone can enhance the secondary separation to capture the back-mixed particles again so as to protect the efficiency. In addition, it is found that the enhanced secondary separation could come from either the stagnant current of axial velocity in the center or the improved tangential velocity of inner vortex whereas the forcibly extending the length of vortex to exceed its natural length will not significantly increase efficiency. 展开更多
关键词 Cyclone separator Cyclone height Natural vortex length Efficiency Secondary separation
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Obtaining accurate measurements of the sea surface height from a GPS buoy 被引量:1
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作者 Wanlin Zhai Jianhua Zhu +5 位作者 Chuntao Chen Wu Zhou Longhao Yan Yufei Zhang Xiaoqi Huang Kai Guo 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第6期78-88,共11页
A dedicated GPS buoy is designed for calibration and validation(Cal/Val)of satellite altimeters since 2014.In order to evaluate the accuracy of the sea surface height(SSH)measured by the GPS buoy,twelve campaigns have... A dedicated GPS buoy is designed for calibration and validation(Cal/Val)of satellite altimeters since 2014.In order to evaluate the accuracy of the sea surface height(SSH)measured by the GPS buoy,twelve campaigns have been done within China sea area between 2014 and 2021.In six of these campaigns,two static Global Navigation Satellite System stations were installed at distances of<1 km and 19 km from the buoy to assess how the baseline length influenced the derived SSH from the buoy solutions.The GPS buoy data was processed using the GAMIT/GLOBK software+TRACK module and CSRS-PPP tool to achieve the SSH.The SSH was compared with conventionally tide gauge(TG)data to evaluate the accuracy of the buoy with the standard deviation of the height element.The results showed that the difference in the standard deviation of the SSH from the buoy and the TG was less than 16 mm.The SSHs processed with different ephemeris(Ultra-Rapid,Rapid,Final)were not significantly different.When the baseline length was 19 km,the SSH solution of the GPS buoy performed well,with standard bias of less than 26 mm between the heights measured by the buoy and TG,meaning that the buoy could be used for Cal/Val of altimeters.The bias between the Canadian Spatial Reference System-precise point positioning tool and the TRACK varied a lot,and some of them were over 130 mm.This deemed too high to be useful for Cal/Val of satellite altimeters.Moreover,the GPS buoy solutions processed by GAMIT/GLOBK software+TRACK module were used for in-orbit Cal/Val of HY-2B/C satellites in ten campaigns.The SSH and significant wave height of the altimeters showed good agreements with the GPS buoy solutions. 展开更多
关键词 GPS buoy sea surface height baseline length precise point positioning satellite altimeter HY-2
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Reconstructing the size of individual trees using log data from cut-to-length harvesters in Pinus radiata plantations: a case study in NSW, Australia 被引量:4
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作者 Kuan Lu Huiquan Bi +2 位作者 Duncan Watt Martin Strandgard Yun Li 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第1期13-33,共21页
With their widespread utilization, cut-to-length harvesters have become a major source of ‘‘big data’’ for forest management as they constantly capture, and provide a daily flow of, information on log production a... With their widespread utilization, cut-to-length harvesters have become a major source of ‘‘big data’’ for forest management as they constantly capture, and provide a daily flow of, information on log production and assortment over large operational areas. Harvester data afford the calculation of the total log length between the stump and the last cut but not the total height of trees. They also contain the length and end diameters of individual logs but not always the diameter at breast height overbark(DBHOB) of harvested stems largely because of time lapse, operating and processing issues and other system deficiencies. Even when DBHOB is extracted from harvester data, errors and/or bias of the machine measurements due to the variation in the stump height of harvested stems from that specified for the harvester head prior to harvesting and diameter measurement errors may need to be corrected. This study developed(1) a system of equations for estimating DBHOB of trees from diameter overbark(DOB) measured by a harvester head at any height up to 3 m above ground level and(2) an equation to predict the total height of harvested stems in P. radiata plantations from harvester data. To generate the data required for this purpose, cut-to-length simulations of more than 3000 trees with detailed taper measurements were carried out in the computer using the cutting patterns extracted from the harvester data and stump height survey data from clearfall operations. The equation predicted total tree height from DBHOB, total log length and the small end diameter of the top log. Prediction accuracy for total tree height was evaluated both globally over the entire data space and locally within partitioned subspaces through benchmarking statistics. These statistics were better than that of the conventional height-diameter equations for P. radiata found in the literature, even when they incorporated stand age and the average height and diameter of dominant trees in the stand as predictors. So this equation when used with harvester data would outperform the conventional equations in tree height prediction. Tree and stand reconstructions of the harvested forest is the necessary first step to provide the essential link of harvester data to conventional inventory, remote sensing imagery and Li DAR data. The equations developed in this study will provide such a linkage for the most effective combined use of harvester data in predicting the attributes of individual trees, stands and forests, and product recovery for the management and planning of P. radiata plantations in New South Wales, Australia. 展开更多
关键词 Cut-to-length simulations Harvesters Big data Diameter and height estimation
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DESIGN OF DIGITAL IMPACTING FILTER IN CP-EBPSK WITH RANDOM-POLAR COMMUNICATION SYSTEM 被引量:4
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作者 Jin Yi Wu Lenan +1 位作者 Chen Yifang Yu Jing 《Journal of Electronics(China)》 2012年第3期328-333,共6页
To solve the difficulty of designing digital impacting filter in the receiver of random-polar modulated Extended Binary Phase Shift Keying with Continuous Phase (CP-EBPSK), a design method based on Quantum-behaved Par... To solve the difficulty of designing digital impacting filter in the receiver of random-polar modulated Extended Binary Phase Shift Keying with Continuous Phase (CP-EBPSK), a design method based on Quantum-behaved Particle Swarm Optimization (QPSO) algorithm is proposed. Firstly, QPSO is introduced elaborately, and the basic flow of QPSO is also given. Then, the demodulation principle of digital impacting filter in the communication system of CP-EBPSK with random-polar is demonstrated, and QPSO is utilized to design the digital impacting filter, which also takes the effect of finite word length into consideration when implemented by hardware. Finally, the proposed method is simulated. Simulation results show that the digital impacting filter designed by new method can derive satisfied demodulation performance. 展开更多
关键词 Extended Binary Phase Shift Keying with Continuous Phase (CP-EBPSK) digital impacting filter Quantum-behaved Particle Swarm Optimization algorithm (QPSO) DEMODULATION Effect of finite word length
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Assessment of the global Copernicus,NASADEM,ASTER and AW3D digital elevation models in Central and Southern Africa 被引量:2
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作者 Chukwuma J.Okolie Jon P.Mills +4 位作者 Adedayo K.Adeleke Julian L.Smit Maria V.Peppa Arif O.Altunel Ikenna D.Arungwa 《Geo-Spatial Information Science》 CSCD 2024年第4期1362-1390,共29页
Validation studies of global Digital Elevation Models(DEMs)in the existing literature are limited by the diversity and spread of landscapes,terrain types considered and sparseness of groundtruth.Moreover,there are kno... Validation studies of global Digital Elevation Models(DEMs)in the existing literature are limited by the diversity and spread of landscapes,terrain types considered and sparseness of groundtruth.Moreover,there are knowledge gaps on the accuracy variations in rugged and complex landscapes,and previous studies have often not relied on robust internal and external validation measures.Thus,there is still only partial understanding and limited perspective of the reliability and adequacy of global DEMs for several applications.In this study,we utilize a dense spread of LiDAR groundtruth to assess the vertical accuracies of four medium-resolution,readily available,free-access and global coverage 1 arc-second(30 m)DEMs:NASADEM,ASTER GDEM,Copernicus GLO-30,and ALOS World 3D(AW3D).The assessment is carried out at landscapes spread across Cape Town,Southern Africa(urban/industrial,agricultural,mountain,peninsula and grassland/shrubland)and forested national parks in Gabon,Central Africa(low-relief tropical rainforest and high-relief tropical rainforest).The statistical analysis is based on robust accuracy metrics that cater for normal and non-normal elevation error distribution,and error ranking.In Cape Town,Copernicus DEM generally had the least vertical error with an overall Mean Error(ME)of 0.82 m and Root Mean Square Error(RMSE)of 2.34 m while ASTER DEM had the poorest performance.However,ASTER GDEM and NASADEM performed better in the low-relief and high-relief tropical forests of Gabon.Generally,the DEM errors have a moderate to high positive correlation in forests,and a low to moderate positive correlation in mountains and urban areas.Copernicus DEM showed superior vertical accuracy in forests with less than 40%tree cover,while ASTER and NASADEM performed better in denser forests with tree cover greater than 70%.This study is a robust regional assessment of these global DEMs. 展开更多
关键词 Global digital elevation model NASADEM ASTER ALOS World 3D COPERNICUS LiDAR NASA Land Vegetation and Ice Sensor(LVIS) height error map
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Depressed female cynomolgus monkeys(Macaca fascicularis) display a higher second-to-fourth(2D:4D)digit ratio
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作者 Wei Li Ling-Yun Luo +6 位作者 Xun Yang Yong He Bin Lian Chao-Hua Qu Qing-Yuan Wu Jian-Guo Zhang Peng Xie 《Zoological Research》 SCIE CAS CSCD 2019年第3期219-225,共7页
This research aimed to provide evidenee of a relationship between digit ratio and depression status in the cynomolgus monkey(Macaca fascicularis).In stable cyno molgus mon key social groups,we selected 15 depressed mo... This research aimed to provide evidenee of a relationship between digit ratio and depression status in the cynomolgus monkey(Macaca fascicularis).In stable cyno molgus mon key social groups,we selected 15 depressed monkeys based on depressive-like behavioral criteria and 16 normal control mon keys.All animals were video recorded for two weeks,with the duration and frequency of the core depressive behaviors and 58 other behaviors in 12 behavioral categories then evaluated via behavioral analysis.Fin ger len gths from the right and left forelimb hands of both groups were measured by X-ray imagi ng.Fin ger length and digit ratio comparisons between the two groups were con ducted using Stude nt's Mest.In terms of the durati on of each behavior,signifies nt differences emerged in“Huddling”and five other behavioral categories,including Ingestive,Amicable,Parental,Locomotive,and Resting.In addition to the above five behavioral categories,we found that depressed mon keys spent less time in parental and rubbing back and forth behaviors than the control group.Furthermore,the 4th fin gers were significantly Ion ger in the left and right hands in the control group relative to the depressed mon keys.The sec ond?to?fourth(2D:4D)digit ratio in the left and right forelimb hands was significantly lower in the control group tha n that in the depressed group.Our fin dings revealed significant differences in finger lengths and digit ratios between depressed mon keys and healthy controls,which concords with our view that relatively high fetal testosterone exposure may be a protective factor against developing depressive symptoms(or that low fetal testosterone exposure is a risk factor). 展开更多
关键词 Fin ger length digit ratio Major DEPRESSIVE disorder CYNOMOLGUS MON key
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Effect of Dominant Semi-Dwarf Gene on Plant Height and Its Related Traits and Sensitivity to Gibberellic Acid in Rice
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作者 LIU Bin-mei CHENG Can +4 位作者 Wu Yue-jin TONG Ji-ping WU Jin-hua ZHANG Ying YUAN Qin 《Rice science》 SCIE 2006年第3期179-184,共6页
Six pairs of tall and dwarf near-isogenic lines derived from a dominant semi-dwarf mutant (Y98149) were selected to study height expression and sensitivity to gibberellic acid (GA3). The lengths of the 4-5th inter... Six pairs of tall and dwarf near-isogenic lines derived from a dominant semi-dwarf mutant (Y98149) were selected to study height expression and sensitivity to gibberellic acid (GA3). The lengths of the 4-5th internode, the 3rd, 2nd, 1st internodes from the top and the panicle length in the six dwarf near isogenic lines were 97.2%, 53.3%, 65.1%, 61.9% and 94.7% of those in the six tall ones, respectively, indicating that the dominant semi-dwarfing gene significantly inhibited the internode elongation. Moreover, Y98149 (mutant type) was more sensitive to GA3 than Y98148 (wild type), and had a lower GA3 concentration in plant, about 78% of Y98148. 展开更多
关键词 semi-dwarf gene near isogenic lines plant height internode length sensitivity gibberellic acid RICE
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Development of the HL-2M digital pulse analysis system
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作者 Yinhai PAN Bowen ZHENG +1 位作者 Wei ZHANG Zejie YIN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第11期93-98,共6页
A digital pulse analysis system is an important diagnostic system in nuclear physics experimental research.In response to the demand for reflecting the particle state in a nuclear physics experiment,we have designed a... A digital pulse analysis system is an important diagnostic system in nuclear physics experimental research.In response to the demand for reflecting the particle state in a nuclear physics experiment,we have designed and developed a real-time digital pulse analysis system and applied it to the digital nuclear pulse waveform discrimination of different detectors in the HL-2M tokamak.The system is based on the peripheral component interconnect extensions for instrumentation(PXI)platform,while its software was written in LABVIEW.The key technologies involved in the system implementation include digital pulse analysis technology,digital discrimination technology,pulse height analysis technology,etc.The system has been applied to the plastic scintillator detector at the Neutron Source Lab of the University of Science and Technology of China.And the experimental results indicate that the system can discriminate between neutron(n)particles and gamma(γ)particles well when used to measure the plastic scintillator detector. 展开更多
关键词 digital pulse analysis plastic scintillator detector digital discrimination pulse height analyses
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