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睡眠中深呼吸引起 R-R 最大变量的观察
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作者 吴学勤 曹金兰 +1 位作者 章露明 庄利民 《现代诊断与治疗》 CAS 1997年第4期226-227,共2页
睡眠中深呼吸引起R-R最大变量的观察吴学勤1曹金兰1章露明1庄利民2(1.安徽省立医院,合肥2300012.安徽省人大门诊部)目前,心脏节律R-R间期的变化已被作为一种评价心脏性猝死危险的独立因素。为了观察窦性心律的... 睡眠中深呼吸引起R-R最大变量的观察吴学勤1曹金兰1章露明1庄利民2(1.安徽省立医院,合肥2300012.安徽省人大门诊部)目前,心脏节律R-R间期的变化已被作为一种评价心脏性猝死危险的独立因素。为了观察窦性心律的自发呼吸波动,我们用Holter心... 展开更多
关键词 睡眠 深呼吸 心脏节律 R-R间期 大变量
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大变量逻辑函数求补的递归实现
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作者 刘维富 《微机发展》 2002年第5期18-21,共4页
逻辑函数求补是大变量逻辑优化的算法基础。采用二叉树结构 ,用C语言实现了大变量逻辑函数求补递归算法。详述了求补二叉树的结构和形成过程 ,以及在求补二叉树上补集的收集方法。
关键词 大变量逻辑函数求补 递归 集成电路 逻辑设计 最优化 二叉树 数据结构
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从“最大变量”到“最大增量”:自媒体时代高校思想政治教育的新视野 被引量:12
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作者 刘醒 张健 《江苏高教》 CSSCI 北大核心 2019年第11期74-79,共6页
自媒体的蓬勃发展为高校思想政治工作带来前所未有的挑战。文章从分析自媒体环境下的教育内容、教育主体、教育对象以及教育过程的显著变化出发,展开对思想政治工作影响因素的研究,重新审视自媒体时代高校思想政治工作的工作方式、工作... 自媒体的蓬勃发展为高校思想政治工作带来前所未有的挑战。文章从分析自媒体环境下的教育内容、教育主体、教育对象以及教育过程的显著变化出发,展开对思想政治工作影响因素的研究,重新审视自媒体时代高校思想政治工作的工作方式、工作环境、工作对象和工作目标,致力于将最大的挑战变为更大的机遇,从而开辟工作的新视野。 展开更多
关键词 自媒体 高校思想政治教育 大变量 最大增量
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由最大变量变成最大增量:增强党的网络执政本领论析 被引量:1
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作者 田旭明 廖慧勤 《学习论坛》 北大核心 2019年第10期32-36,共5页
在网络时代,党的执政本领不仅体现在现实社会,还体现在虚拟社会,引导和驾驭网络,善于用网执政、以网促政。当前,增强党的网络执政本领面临着一些党员干部网络基本素养欠缺、“网事”处置本领不强、现实社会矛盾负效应虚拟延伸等障碍。因... 在网络时代,党的执政本领不仅体现在现实社会,还体现在虚拟社会,引导和驾驭网络,善于用网执政、以网促政。当前,增强党的网络执政本领面临着一些党员干部网络基本素养欠缺、“网事”处置本领不强、现实社会矛盾负效应虚拟延伸等障碍。因此,要从主体能力提升、网络群众工作、网络法治化、网络安全保障、社会环境优化等具体层面探索行之有效的实践对策,增强党驾驭网络的本领,强化党在网络社会的执政力,使互联网这个最大变量成为党和国家事业发展的最大增量。 展开更多
关键词 网络社会 执政本领 大变量 最大增量
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Modeling dam deformation using independent component regression method 被引量:3
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作者 戴吾蛟 刘斌 +1 位作者 丁晓利 黄大伟 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第7期2194-2200,共7页
In the application of regression analysis method to model dam deformation, the ill-condition problem occurred in coefficient matrix always prevents an accurate modeling mainly due to the multicollinearity of the varia... In the application of regression analysis method to model dam deformation, the ill-condition problem occurred in coefficient matrix always prevents an accurate modeling mainly due to the multicollinearity of the variables. Independent component regression (ICR) was proposed to model the dam deformation and identify the physical origins of the deformation. Simulation experiment shows that ICR can successfully resolve the problem of ill-condition and produce a reliable deformation model. After that, the method is applied to model the deformation of the Wuqiangxi Dam in Hunan province, China. The result shows that ICR can not only accurately model the deformation of the dam, but also help to identify the physical factors that affect the deformation through the extracted independent components. 展开更多
关键词 dam deformation analysis independent component regression principal component regression ill-condition problem interpreting of dam deformation
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载瓶架的变薄拉伸翻边工艺
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作者 吴维奇 《模具工业》 1998年第4期20-22,共3页
介绍了连续多个排列大变量变薄拉伸、翻边工艺中出现的问题及其解决办法。实践证实了该工艺方法为解决这类连续多个排列大变量变薄拉伸、翻边工艺难题,探索出一条行之有效的途径。
关键词 大变量 变薄拉伸 翻边高度 中心节距 载瓶架
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An Accelerated Simulation Method for ELDRS of Bipolar Operational Amplifiers Using a Dose-Rate Switching Experiment
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作者 陆妩 任迪远 +2 位作者 郑玉展 郭旗 余学峰 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第7期1286-1291,共6页
Through different dose-rate switching evaluation methods,the radiation-response rules of operational amplifiers are studied when the irradiation dose rate is switched from high to low under different radiation tempera... Through different dose-rate switching evaluation methods,the radiation-response rules of operational amplifiers are studied when the irradiation dose rate is switched from high to low under different radiation temperatures and total doses. The experimental results indicate that the response characteristics could be affected by the switching total doses, irradiation temperatures,and dose rates individually or together. Accelerated evaluation on the ELDRS can be realized by adopting a proper dose-rate switching method. Meanwhile, the irradiation time can also be reduced. Finally, the mechanisms of the difference between various radiation responses are analyzed. 展开更多
关键词 bipolar OP-amps ^60Co γ radiation switching dose rates accelerated evaluation
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Calculation of Valence Subband Structures for Strained Quantum-Wells by Plane Wave Expansion Method Within 6×6 Luttinger-Kohn Model
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作者 国伟华 黄永箴 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第6期577-581,共5页
The valence subband energies and wave functions of a tensile strained quantum well are calculated by the plane wave expansion method within the 6×6 Luttinger Kohn model.The effect of the number and period of pla... The valence subband energies and wave functions of a tensile strained quantum well are calculated by the plane wave expansion method within the 6×6 Luttinger Kohn model.The effect of the number and period of plane waves used for expansion on the stability of energy eigenvalues is examined.For practical calculation,it should choose the period large sufficiently to ensure the envelope functions vanish at the boundary and the number of plane waves large enough to ensure the energy eigenvalues keep unchanged within a prescribed range. 展开更多
关键词 semiconductor optical amplifier strained quantum well plane wave expansion method POLARIZATION
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Support principles of NPR bolt/cable and control techniques of large-deformation disasters 被引量:7
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作者 Tao Zhigang Zhang Haijiang +1 位作者 Chen Yifan Jiang Chaochao 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第6期967-973,共7页
Deep mining has been paid much more attention because of the depletion of shallow mining resources.Traditional bolts could be invalid to accommodate large displacement and deformation in geomaterials.Consequently, alt... Deep mining has been paid much more attention because of the depletion of shallow mining resources.Traditional bolts could be invalid to accommodate large displacement and deformation in geomaterials.Consequently, alternative support and reinforcement bolts need to be studied and their constitutive models also need to be developed to help understanding for the complex stress-strain responses of rock masses under loadings. The effect of Negative Poisson's Ratio(NPR) that is attributed to the swelling phenomenon along the lateral direction may appear in metal materials under tensional loadings. Thence NPR materials often have an advantage over NPR ones in mechanical behavior such as impact resistance, antishearing, and energy absorbed. From the characteristics of NPR materials, a series of bolt and cable supports with the effect of NPR and constant-resistance have been recently developed. We here firstly introduce the structural features of NPR support. Then the constitutive model of NPR support is presented and its corresponding equation of energy equilibrium. Its basic principle interacted on rock masses is further discussed. Finally, NPR cables are employed to support the slope of an open-pit mine. The applications show that NPR cables can ease failure within the slope and play an important role in predicting and providing early warning of slope failure, together with a monitoring system of slope stability. 展开更多
关键词 Negative Poisson's Ratio (NPR)Large-deformation related disaster Constitutive relationship Landslide prediction
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Macroalgae in a spring stream in Shanxi Province:composition and relation to physical and chemical variables 被引量:1
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作者 胡变芳 谢树莲 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2007年第3期317-321,共5页
Fourteen stream segments were investigated throughout the Xin’an Spring in Shanxi Province, China in 2004. The variation ranges in stream size, current velocity, discharge, dissolved oxygen, and specific conductance ... Fourteen stream segments were investigated throughout the Xin’an Spring in Shanxi Province, China in 2004. The variation ranges in stream size, current velocity, discharge, dissolved oxygen, and specific conductance were large. Twenty-two macroalgae species were found in the stream. Major divisions in terms of species numbers were Chlorophyta (59.1%), Cyanophyta (22.8%), Xanthophyta (9.1%), Rhodophyta (4.5%) and Charophyta (4.5%). The most widespread species, Cladophora rivularis (50.0%), also Oedogonium sp. (42.9%) and Spirogyra sp. (42.9%) were well represented throughout the stream, whereas another 10 species were found in only one sampling site. Total percentage cover varied from <1% to 90%. Red algae Batrachospermum acuatum and the charophytes Chara vulgaris have the highest percentage cover. Among the parameters analyzed, the stream width, specific conductance and dissolved oxygen were the ones that more closely related to the species number and percentage cover of macroalgal communities. The species number of each site was negatively correlated with dissolved oxygen content. The total percentage cover of the macroalgae was negatively correlated with the stream width and the specific conductance. 展开更多
关键词 stream macroalgae COMPOSITION physical and chemical factors spring stream Xin'an Spring SHANXI China
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Interannual salinity variability of the Northern Yellow Sea Cold Water Mass 被引量:3
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作者 李昂 于非 刁新源 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第3期779-789,共11页
This paper discusses the interannual variability of the Northern Yellow Sea Cold Water Mass(NYSCWM) and the factors that influence it,based on survey data from the 1976–2006 national standard section and the Korea Oc... This paper discusses the interannual variability of the Northern Yellow Sea Cold Water Mass(NYSCWM) and the factors that influence it,based on survey data from the 1976–2006 national standard section and the Korea Oceanographic Data Center,monthly E-P flux data from the European Centre for Medium-Range Weather Forecasts,and meridional wind speed data from the International Comprehensive Ocean-Atmosphere Data Set. The results show that:1) the mean salinity of the NYSCWM center has a slightly decreasing trend,which is not consistent with the high salinity center; 2) both the southern salinity front and the halocline of the NYSCWM display a weakening trend,which indicates that the difference between the NYSCWM and coastal water decreases; 3) the Yellow Sea Warm Current intrusion,the E-P flux of the northern Yellow Sea,and the strength of the winter monsoon will affect the NYSCWM salinity during the following summer. 展开更多
关键词 Northern Yellow Sea Cold Water Mass (NYSCWM) SALINITY interannual variability linear trend
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PVC gel bio-inspired adhesives with variable modulus and its application in a gripper 被引量:2
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作者 ZHANG Hao HE Qing-song +3 位作者 TIAN Cheng-bo WU Yu-wei ZHAO Ze-fang YU Min 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第6期1778-1787,共10页
Inspired by the microstructure of gecko’s toe,two kinds of polyvinyl chloride(PVC)gels with different modulus were poured on a silicon mold with micropillars,and then a bio-inspired adhesive with variable modulus was... Inspired by the microstructure of gecko’s toe,two kinds of polyvinyl chloride(PVC)gels with different modulus were poured on a silicon mold with micropillars,and then a bio-inspired adhesive with variable modulus was manufactured in this study.The adhesions of variable modulus and fixed modulus bio-inspired adhesives were tested,respectively,on a smooth glass and a printed circuit board(PCB)with different surface structures.The results show that PVC gel bio-inspired adhesives with variable modulus have many advantages compared with the fixed modulus bioinspired adhesives.The adhesion of variable modulus bio-inspired adhesives on the rough PCB surface increased by 2−5 times,and due to the use of variable modulus of PVC gel,the surface micropillars can maintain high aspect ratio and flexible tips at the same time.Moreover,the use of PVC gel makes it easier to demold during the bio-inspired adhesives preparation.An adhesion-desorption device was made according to the movement of the gecko toes,and the PCB was successfully grasped. 展开更多
关键词 bio-inspired adhesives GECKO PVC gel variable modulus
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In-situ synchrotron X-ray diffraction investigation on deformation behavior of Nb/NiTi composite during pre-straining process 被引量:1
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作者 Shun GUO Hui-hui ZHANG +6 位作者 Min-kyung KWAK Wang DING Guang-lei LIU Wen MA Hai-xia LIU Qing-kun MENG Xin-qing ZHAO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第8期2609-2619,共11页
The mechanisms responsible for deformation behavior in Nb/NiTi composite during pre-straining were investigated systematically using in-situ synchrotron X-ray diffraction, transmission electron microscopy and tensile ... The mechanisms responsible for deformation behavior in Nb/NiTi composite during pre-straining were investigated systematically using in-situ synchrotron X-ray diffraction, transmission electron microscopy and tensile test. It is shown that upon loading, the composite experiences elastic elongation and slight plastic deformation of B19′,B2 and β-Nb phases, together with the forward stress-induced martensitic(SIM) transformation from B2 to B19′. Upon unloading, the deformation mechanisms of the composite mainly involve elastic recovery of B19′, B2 and β-Nb phases,compression deformation of β-Nb phase and incomplete B19′→B2 reverse SIM transformation. In the tensile loading-unloading procedure, besides the inherent elastic deformation and SIM transformation, the(001) compound twins in B19′ martensite can also be conducive to the elastic deformation occurring in B19′-phase of the composite.Therefore, this composite can exhibit a large recoverable strain after unloading owing to the elastic deformation, and the partially reversible and consecutive SIM transformation together with the(001) compound twins. 展开更多
关键词 Nb/NiTi composite near-linear deformation behavior large recoverable strain martensitic transformation
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Oil–water two-phase flow pattern analysis with ERT based measurement and multivariate maximum Lyapunov exponent 被引量:8
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作者 谭超 王娜娜 董峰 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第1期240-248,共9页
Oil–water two-phase flow patterns in a horizontal pipe are analyzed with a 16-electrode electrical resistance tomography(ERT) system. The measurement data of the ERT are treated as a multivariate time-series, thus th... Oil–water two-phase flow patterns in a horizontal pipe are analyzed with a 16-electrode electrical resistance tomography(ERT) system. The measurement data of the ERT are treated as a multivariate time-series, thus the information extracted from each electrode represents the local phase distribution and fraction change at that location. The multivariate maximum Lyapunov exponent(MMLE) is extracted from the 16-dimension time-series to demonstrate the change of flow pattern versus the superficial velocity ratio of oil to water. The correlation dimension of the multivariate time-series is further introduced to jointly characterize and finally separate the flow patterns with MMLE. The change of flow patterns with superficial oil velocity at different water superficial velocities is studied with MMLE and correlation dimension, respectively, and the flow pattern transition can also be characterized with these two features. The proposed MMLE and correlation dimension map could effectively separate the flow patterns, thus is an effective tool for flow pattern identification and transition analysis. 展开更多
关键词 oil-water two-phase flow flow patterns electrical resistance tomography (ERT) multivariate time-series multivariate maximum Lyapunov exponent correlation dimension
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High-resolution remote sensing image-based extensive deformation-induced landslide displacement field monitoring method 被引量:16
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作者 Shanjun Liu Han Wang +1 位作者 Jianwei Huang Lixin Wu 《International Journal of Coal Science & Technology》 EI 2015年第3期170-177,共8页
Landslide is one of the multitudinous serious geological hazards. The key to its control and reduction lies on dynamic monitoring and early warning. The article points out the insufficiency of traditional measuring me... Landslide is one of the multitudinous serious geological hazards. The key to its control and reduction lies on dynamic monitoring and early warning. The article points out the insufficiency of traditional measuring means applied for large-scale landslide monitoring and proposes the method for extensive landslide displacement field monitoring using high- resolution remote images. Matching of cognominal points is realized by using the invariant features of SIFT algorithm in image translation, rotation, zooming, and affine transformation, and through recognition and comparison of characteristics of high-resolution images in different landsliding periods. Following that, landslide displacement vector field can be made known by measuring the distances and directions between cognominal points. As evidenced by field application of the method for landslide monitoring at West Open Mine in Fushun city of China, the method has the attraction of being able to make areal measurement through satellite observation and capable of obtaining at the same time the information of large- area intensive displacement field, for facilitating automatic delimitation of extent of landslide displacement vector field and sliding mass. This can serve as a basis for making analysis of laws governing occurrence of landslide and adoption of countermeasures. 展开更多
关键词 Landslide monitoring High-resolution remote sensing SIFT algorithm Deformation field
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On Strong Law of Large Numbers for Random Sequence 被引量:1
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作者 WANG Zhong-zhi 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第4期475-480,共6页
This note is devoted to introduce a new concept of conditionally dominated random variables.Under suitable restrict conditions,a general strong law of large numbers for arbitrary continuous random variables is obtained.
关键词 random variable strong law of large numbers conditionally dominated random sequence
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Application of Geodetic Receivers to Timing and Time Transfer 被引量:1
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作者 NIEGuigen LIUJingnan 《Geo-Spatial Information Science》 2005年第1期8-13,共6页
Two methods for smoothing pseudorange observable by Carrier and Doppler are discussed. Then the procedure based on the RINEX observation files is tested using the Ashtech Z-XII3T geodetic receivers driven by a stable ... Two methods for smoothing pseudorange observable by Carrier and Doppler are discussed. Then the procedure based on the RINEX observation files is tested using the Ashtech Z-XII3T geodetic receivers driven by a stable external frequency at UNSO. This paper proposes to adapt this procedure for the links between geodetic receivers, in order to take advantage of the P codes available on L 1 and L 2. This new procedure uses the 30-second RINEX observations files, the standard of the International GPS Service (IGS), and processes the ionosphere-free combination of the codes P 1 and P 2; the satellite positions are deduced from the IGS rapid orbits, available after two days. 展开更多
关键词 GPS time and frequency transfer GEODESY SMOOTHING
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On the Computation of Noether Normalization
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作者 朱烨 张江峰 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第2期77-81,共5页
This paper considered the Noether normalization of a finitely generated algebra over an algebraically closed field. It gives a necessary and sufficient condition as well as an algorithm for the identification of those... This paper considered the Noether normalization of a finitely generated algebra over an algebraically closed field. It gives a necessary and sufficient condition as well as an algorithm for the identification of those algebraically independent variables, then uses these elements to construct the Noether normalization of this algebra. 展开更多
关键词 Noether normalization maximally independent variables Groebner basis
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Large Deviations for Sums of Heavy-tailed Random Variables
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作者 郭晓燕 孔繁超 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第2期282-289,共8页
This paper is a further investigation of large deviations for sums of random variables Sn=i=1∑n Xi and S(t)=i=1∑N(t)Xi,(t≥0), where {X_n,n≥1) are independent identically distribution and non-negative random... This paper is a further investigation of large deviations for sums of random variables Sn=i=1∑n Xi and S(t)=i=1∑N(t)Xi,(t≥0), where {X_n,n≥1) are independent identically distribution and non-negative random variables, and {N(t),t≥0} is a counting process of non-negative integer-valued random variables, independent of {X_n,n≥1}. In this paper, under the suppose F∈G, which is a bigger heavy-tailed class than C, proved large deviation results for sums of random variables. 展开更多
关键词 large deviation heavy-tailed distribution strongly subexponential distribution lognormal distribution
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Topographic Indices and Yield Variability in a Rolling Landscape of Western Canada 被引量:2
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作者 CHI Bao-Liang BING Cheng-Si +1 位作者 F. WALLEY T. YATES 《Pedosphere》 SCIE CAS CSCD 2009年第3期362-370,共9页
Understanding the relationships between topographic indices and crop yield variability is important for soil manage- ment and crop production in rolling landscape. Two agricultural fields at Alvena and Hepburn, Saskat... Understanding the relationships between topographic indices and crop yield variability is important for soil manage- ment and crop production in rolling landscape. Two agricultural fields at Alvena and Hepburn, Saskatchewan, Canada were selected to examine how topographic indices were related to wheat yield under two topographic and weather conditions in the Canadian prairies. The landscapes of the two sites are classified as hummocky and the dominant soil type is an Aridic Ustoll. The relationships among yield, topography, soil, and weather were analyzed using wheat (Triticum aestivum L.) grain yield from Alvena in 2001 (dry year) and 2004 (wet year) and from Hepburn in 1998 (dry year). Topographic/soil indices included relative elevation, wetness index, upslope length, curvature, soil organic matter, and soil moisture storage before seeding. The results indicated that, in the dry years, the correlation coefficients between upslope length and grain yield were 0.79 for the typical rolling landscape (Alvena) in 2001 and 0.73 for shallow gentle rolling landscape (Hepburn) in 1998. In the wet year (2004), the relationships between yield and topographic/soil attributes were not as strong as in dry years. Therefore, upslope length was the best yield indicator for the two landscapes in dry years, whereas no topographic indices were highly correlated to crop yield in wet years. Those topographic indices seemed useful in identifying the yield variability and delineating the proper management zone. 展开更多
关键词 rolling landscape topographic indices upslope length yield variability
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