用插值算子解FIF反问题

１．引言 记区间Ｉ＝［０,１］,Ｎ是某给定的正整数,ｘｊ＝ｊ／Ｎ,ｊ＝０,１,…,Ｎ,又给定实函数Ｙ．令 ｛ Ｌｎ（ｘ）＝ Ｎ ＋ Ｎ, Ｆｎ（ｘ,ｙ）＝ｄｎ－１ｙ＋ｈＹ（Ｌｎ（ｘ））－ｄｎ－１Ｙ（ｘ）ｂｎ＝１,２…．Ｎ．（１,１） 其中 （１）ｈＹ（ｘ）∈Ｃ（Ｉ）,满足插值条件：ｈＹ（ｘｊ）＝Ｙ（ｘｊ）,ｊ＝０,１;…,Ｎ （２）ｂｙ（ｘ）∈Ｃ（Ｉ）,满足条件：ｂＹ（ｘ０）－Ｙ（ｘ０）,ｂＹ（ｘＮ）＝Ｙ（ｘＮ）; （３）实数列｛ｄｉ｝Ｎ－１ｉ＝０满足｜ｄｉ｜＜１,Ｖｉ． 定义 Ｗｕ （ｘ,ｙ）＝（Ｌｎ（ｘ）…     

在I-DEAS软件上开发的两个实用程序

一．倒角标注 Ｉ－ＤＥＡＳ的倒角标注方式,不符合国标,以下程序可以实现国标标注： ＃ｄｅｌｅｔｅ ａｌｌ ＃ｇｅｔ ｄｉｇｔｉｚｅ （ｘｌ,ｙｌ,ｓｔｌ） ＃ｉｆ （ｓｔｌ ｎｅ ０） ｔｈｅｎ ｇｏｔｏｔｈｅｅｎｄ ＃ｇｅｔ ｄｉｇｔｉｚｅ （ｘ２,ｙ２,ｓｔ２） ＃ｉｆ（ｓｔ２ ｎｅ ０） ｔｈｅｎ ｇｏｔｏｔｈｅｅｎｄ ＃ａｌｐｈ＝ａｔａｎ（（ｙ２－ｙ１）／（ｘ２－Ｘ１）） ＃ａ＝Ｉｎｔｔｏｓｔｒ（ＴＲＵＮ（ａｂｓ（ａｌｐｈ））） ＃１＝ａｂｓ（ｘ２－ｘ１） ＃ｉｆ（１ｎｅ ＴＲＵＮＣ（１）） ｔｈｅｎｓｅｔ ｐｒ…     

关于S_4~2(△_(mn)~((2)))插值与逼近

§１．引言及定义 设平面上矩形 Ｄ：［a,b］×［ｃ,ｄ］上的 Ⅱ型三角剖分（图５）．令 ｈ１＝,ｈ２＝．为方便,（ｉ,ｊ）（ｉｈ１,ｊｈ２）．记表示总次数不超过４的二元多项式空间;Ｄｉｊ表示以（ｉ,ｊ）,（ｉ ＋１,ｊ）（ｉ,ｊ＋１）,（ｉ＋１, ｊ＋１）为顶点的矩形,其上的四个三角形域依次记为（ｋ＝１,２,３,４）． 定义 １．１．二元四次样条集S_4～2（△_（mm）～（（２）））是由满足下列条件的Ｓ（ｘ,ｙ）所组成的集合： （ｉ） Ｓ（ｘ,ｙ） Ｃ２（Ｄ）;（ｉｉ）Ｓ（ｘ,ｙ）（ｋ＝１,２,３,４）． 设一…     

玉米弯孢菌叶斑病菌毒素的生物活性测定及对玉米叶片超微 …

玉米弯孢菌叶斑病（Ｃｕｒｖｕｌａｒｉａｌｕｎａｔａ）是目前玉米生产的一个主要病害,该病菌可以产生毒素,本文对玉米弯孢菌叶斑病菌产生的毒素进行了生物学测定,并观察了毒素对寄主叶片超微结构的破坏作用,证明玉米弯孢菌叶斑病菌产生的毒素是其致病因子之一,研究发现该毒素不是蛋白质。     

玉米弯孢菌叶斑病菌毒素的生物活性测定及对玉米叶片超微结构的影响

玉米弯孢菌叶斑病（Curvularialunata）是目前玉米生产上的一个主要病害,该病菌可以产生毒素。本文对玉米弯孢菌叶斑病菌产生的毒素进行了生物学测定,并观察了毒素对寄主叶片超微结构的破坏作用。证明玉米弯孢菌叶斑病菌产生的毒素是其致病因子之一,研究发现该毒素不是蛋白质。     

一类本身具有预条件功能的ABS型共轭梯度算法

１．引言对于大型线性方程组Ａｘ＝ｂ,其中ＡＥＲｎｘｎ是一个非奇异矩阵,ｘ,ｂＲｎＶｏｙｅｖｏｄｉｎ［７］提出了一类共轭梯度算法．该算法中含有两个作为参数的非奇异矩阵Ｂ;ＣＲｎｘｎ,它们满足关系式ＣＡＢＣ－１＝ａＩ＋βＢＴＡＴ,（１）其中ａβＲ为纯量．设内积（ｘ,ｙ）＝ｙＴｘ为普通数量积,Ｖｏｙｅｖｏｄｉｎ共轭梯度法如下：算法１．步０．设。０为精确解０”的一个初始近似,计算残差,。一＊。。一ｂ．若,。＝０则停止;否则,置Ｓ。＝,。,ｉ二０,转步１．步１．计算。;＋１。;一（,;,＊,Ｊ八,;,＊＊…     

157百合（Lilium cr.Gran sasso）染色体核型研究

本文对１５７百合进行了染色体核型研究,结果表明：１５７百合体细胞染色体数为２ｎ＝２ｘ＝２４;染色组成为Ｒ（２ｎ）＝２ｘ＝２ｍ（ＳＡＴ）＋２ｍ＋２Ｓｍ（ＳＡＴ）＋１６Ｓｔ＋２ｔ;在第１,２,对染色体上有随体;其核型分类属于３Ｂ型。     

单滞后区间动力系统的稳定性

本文研究如下单滞后时变区间动力系统ｘ（ｔ）＝Ｎ［Ｐ，Ｑ］ｘ（ｔ）＋Ｎ［Ｃ（ｔ），Ｄ（ｔ）］ｘ（ｔ－τ），τ≥０的渐近稳定性的ａ稳定性，给出了其渐近稳定和ａ稳定的充分条件，推广和改进了文［１，２］的工作。     

检验0,1数字序列随机性的多重异或法

１．引言在电信技术中,常常需要检验０,１数字序列｛Ｘｊ,ｊ＝１,…;Ｎ｝（１）的随机性［１］．在随机模拟工作中,对由一般反馈移位寄存器（ＧＦＳＲ）生成的０,１数字序列亦常需作同样的检验．检验序列（１）的随机性就是检验是否可以把它当作某０－１分布随机变量的Ｎ个独立观察值,即的容量为Ｎ的样本（２）的一个现实．异或是一种极易实现的运算,常用于分析序列（１）的结构［２,３］．以ｙ表示对ｘ,ｙ施行异或运算,令Ｘ－Ｘｊ－（３）取适当的Ｎ－１,从序列（１）开始,按式（３）可依次生成Ｎ＊＋１个序列其中Ｘｊ’‘－…     

一个基于布尔方程的简化组合逻辑设计的分解方法

本文提出了简化组合逻辑设计的布尔方程分解方法，是将Ｆ（ｘ１，ｘ２，．．．ｘｎ）＝１的组合逻辑设计转化为Ｆ（ｘ１，ｘ２，．．．ｘｎ）＝０的组合逻辑设计问题，然后将Ｆ（ｘ１，ｘ２，．．．，ｘｎ）＝０转化为与其等价的布尔方程组，对得到的布尔方程组用“异或”逻辑实现，从而获得极为简化的组合逻辑设计，最后我们给出了解布尔方程的程序设计框图。     

Improved ground sampling and crop yield estimation using satellite data

The existing procedures for crop yield estimation involve Crop Cutting Experiments ( CCEs) conducted during harvesting time in the plots selected based on a pre-designed sampling scheme using available ground data. These ground sampling designs do not consider the crop condition which is directly related to the yield during the season, for stratification and subsequent sample selection leading to biased distribution of plots. Moreover these experiments are capable of providing estimates only at larger areal units such as the total command area. Hence there is a need to improve the sampling design to achieve more accurate estimates. An alternate methodology exploiting the information on crop area and crop condition, derived from satellite remote sensing data on near real-time basis, for improving the ground sampling design has been proposed in this paper. The methodology is demonstrated in the Davangere and Malebennur divisions of the Bhadra project command area to estimate the average yield of paddy during Rabi 1992-93. The results obtained from conventional methodology and the improved procedure showed that the latter has increased the accuracy of estimates. The yield values obtained from CCE plots have been regressed with corresponding Normalized Difference Vegetation Index (NDVI) statistics and thus the derived paddy yield model is capable of providing the yield estimates at smaller area 1 units, such as within distributary command.     

关于水稻抛秧栽培减少氮肥用量对产量影响的研究

用田间小区试验的方法，对抛秧栽培条件下的施肥技术进行了研究。结果表明在其它条件相同情况下，与常规插秧栽培相比抛秧水田减少基肥氮肥用量２０％和分蘖肥３２％可获得更高产量，即抛秧栽培应控制前期氮肥用量。     

Using digitized handheld Space Shuttle photography for terrain visualization

Formulas are given to convert land-based vegetative canopy spectral reflectance measurements into Landsat digital counts in the four channels for a clear standard atmosphere. These formulas are shown to predict the curves found by plotting multitemporal Landsat trajectories. With correct interpretation, plots of channel 3 versus channel 4 Landsat data for crops are shown to yield information on both crop identification and crop leaf area index.     

A plot drainage network as a conceptual tool for the spatial representation of surface flow pathways in agricultural catchments

The drainage network must take the farming systems and the landscape structure into consideration to describe flow pathways in the agricultural catchment. A new approach is proposed to build the drainage network which is based on the identification of the inlets and outlets for surface water flow on each farmers’ field (or plot), estimating the relative areas contributing to the surface yield. The delineation of these areas and their links in terms of surface flow pathways provides us with a pattern of relationships between individual plots, i.e. going from each plot to the other plots over the entire catchment. In this approach, flow directions are firstly calculated in the usual way by taking account of slope direction. Plot outlets are defined from the digital elevation model (DEM) and then linked together using a tree structure. If present, linear networks such as hedges modify both the flow directions and the location of plot outlets, hence modify this tree structure. In a final step, the plots are themselves linked together using a graph structure illustrated by an arrow diagram. This drainage network based on plot outlets is applied to a 15-km² catchment area represented by 38,300 pixels and 2000 plots. This new drainage network takes into consideration 5300 plot outlets, which greatly reduces the number of objects in comparison with a drainage network made up of pixels or DEM cells. This method leads to a simple and functional representation of surface flow pathways in an agricultural catchment. It allows us to identify the key plots controlling stream water pollution where converging flow pathways are coming from numerous or large-sized plots. Finally, it produces a functional representation for decision support.     

Surface spacings from the secondary electron yield

Small inflections in plots of the total yield of secondary electrons versus primary electron energy were reported more than fifty years ago and attributed variously to thresholds for the excitation of core states, and to diffraction of the incident electrons. Although the existence of these inflections was discounted by later researchers, recent studies of the derivative of the yield leave no doubt as to their reality or their origin. The spectrum of core excitation thresholds provides information on the composition of the surface region. Near-threshold structure is related to the electronic state of the atoms. Extended fine structure above the threshold can be inverted to obtain interatomic spacings even from relatively disordered surfaces. The principal limitation in these measurements results from diffraction of the incident electron beam, which produces variations in electron reflectivity. The extreme simplicity of the equipment required makes this technique available to essentially every surface science laboratory.     

ASTER and Landsat ETM+ images applied to sugarcane yield forecast

This paper proposes a method to support sugarcane yield forecast using vegetation spectral indices, principal component analysis and historic yield data. The study area is located in the State of São Paulo, Brazil, and is divided into 11 production plots (108.75 ha), where sugarcane of the RB85 5536 variety is cultivated on red latossol (oxissol‐type) soil and flat topography. The data employed in the study include radiometrically and geometrically corrected enhanced thermatic mapper Plus (ETM+)/Landsat‐7 and ASTER/Terra images, acquired in June and April 2001, respectively, and historic harvest data measured in 2000 and 2001. The method comprises several steps: (a) enhancement of specific spectral responses of vegetation constituents; (b) reduction of spectral dimensions with prioritization of information and weighing of parameters related to foliar area; the data processed through these steps are reduced to a single image (the synthesis image), from which the mean DN (digital number) per cultivated area is calculated; (c) the image DNs are subsequently transformed into ton of stalk per hectare (t ha^?1) through normalization, which requires knowledge of the previous year's yield for the cultivated production plots under analysis. Yield estimates using the method showed greater precision in comparison to the ubiquitous visual methods employed by the sugarcane agro‐industry in Brazil. Using factual productivity data of the year 2000 harvest only, the method achieved estimate errors varying between 2.57% and 5.65%, compared with 9.06% expected by the sugar factory; whereas using data from the year 2001 harvest, error margins were remarkably lower, around 1%.     

Quantifying the yield of risk-bearing IT-portfolios

We proposed a method to quantify the yield of an IT-investment portfolio in an environment of uncertainty and risk. For various common implementation scenarios such as growing demands during implementation without deadline extensions we showed how to monetize their impact on the net present value. Depending on the business case this can lead to higher or lower gains. We also took failure of projects within an IT-investment portfolio into account, by appraising the loss in case of failure, resulting in a more realistic yield. To provide maximal insight into this yield, we proposed to treat it as a stochastic variable. We explained how to infer various portfolio yield distributions: discrete, continuous, and cumulative distributions, leading to useful summaries such as box plots and histograms. We argued that these information-rich characterizations support decision makers in taking calculated risks, and provided insight in how to address IT-specific risks and what such risk mitigation may cost. We explained our approach by quantifying the expected yield of a small four project portfolio under uncertainty and risk, and we provided the results for a larger and realistic IT-investment portfolio.     

Using QuickBird imagery and a production efficiency model to improve crop yield estimation in the semi-arid hilly Loess Plateau,China

Crop yield is a key element in rural development and an indicator of national food security. A method that could estimate crop yield over large hilly areas would be highly desirable. Methods including high spatial resolution satellite imagery have the potential to achieve this objective. This paper describes a method of integrating QuickBird imagery with a production efficiency model (PEM) to estimate crop yield in Zhonglianchuan, a hilly area on Loess Plateau, China. In the PEM model, crop yield is a function of the photosynthetic active radiation (PAR), fraction of absorbed photosynthetically active radiation (f_APAR) and light-use efficiency (LUE). Based on the high spatial resolution QuickBird imagery, a land cover classification is used to attribute a class-specific LUE. The f_APAR is related to spectral vegetation indices (SVI), which can be derived from the satellite images. The LUE, f_APAR and incident PAR data were combined to estimate the crop yield. Farmer-reported crop yield data in 80 representative plots were used to validate the model output. The results indicated QuickBird imagery can improve the accuracy of predicted results relative to the Landsat TM image. The predicted yield approximated well with the data reported by the farmers (r² = 0.86; n = 80). The spatial distributions of crop yield derived here also offers valuable information to manage agricultural production and understand ecosystem functioning.     

The use of a spectroradiometer to study aerial photographs of ozone-treated soybeans

Abstract

Abstract. A scanning spectroradiometer was used to measure the optical densities of an aerial photograph of an experimental field in which soybeans were growing in response to different concentrations of ozone, an air pollutant. The plants were growing in 3 m diameter, 2.4 m high open-top exposure chambers. Correlation coefficients among the film densities, plant yield and visual estimates of non-green leaf area for the 16 test plots were highly significant (p<001); those with ozone treatment concentrations were significant (p<0-05). The early senescence induced by this form of environmental stress can thus be detected by film density differences, and these differences are well correlated with ground indicators of crop condition.     

Point accuracy of a non-parametric method in estimation of forest characteristics with different satellite materials

The reference sample plot (RSP) method is a distance-weighted k nearest neighbour estimation method, which allows simultaneous interpretation of several variables. In the RSP method, the k spectrally nearest field plots are looked at separately for each unknown pixel, and the area weight of the unknown pixel is divided as a function of the spectral distances to the nearest plots. The RSP method was examined in a forest inventory for estimating stem volumes by tree species groups using different satellite materials. Two methods were tested both in searching for and weighting the nearest field plots. Euclidean distance functions worked steadily with all the volume variables studied. The other distance measure tested was based on regression modelling. With more than 15 plots, both covariance weighting and inverse distance weighting gave similar results. Considering the field data of this study, the suitable number of the nearest plots in plotwise estimation appeared to be between 10 and 15 plots. With Landsat TM, SPOT XS and SPOT P, the differences in standard errors were minor. When combined TM and SPOT P were used, the plotwise standard error of total volume was still over 60 per cent.