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Local linear scale factors in map projections in the direction of coordinate axes 被引量:2
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作者 Miljenko Lapaine Nedjeljko Frančula Željka Tutek 《Geo-Spatial Information Science》 SCIE EI CSCD 2021年第4期630-637,共8页
This paper explains that the terms“horizontal and vertical scales”are not appropriate in map projections theory.Instead,the authors suggest using the term“scales in the direction of coordinate axes.”Since it is no... This paper explains that the terms“horizontal and vertical scales”are not appropriate in map projections theory.Instead,the authors suggest using the term“scales in the direction of coordinate axes.”Since it is not possible to read a local linear scale factor in the direction of a coordinate axis immediately from the definition of a local linear scale factor,this paper considers the derivation of new formulae that enable local linear scale factors in the direction of coordinate x and y axes to be calculated.The formula for computing the local linear scale factor in any direction defined by dx and dy is also derived.Furthermore,the position and magnitude of the extreme values of the local linear scale factor are considered and new formulas derived. 展开更多
关键词 Map projection scale factor horizontal scale factor vertical scale factor
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New scale factor correction scheme for CORDIC algorithm 被引量:1
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作者 戴志生 张萌 +1 位作者 高星 汤佳健 《Journal of Southeast University(English Edition)》 EI CAS 2009年第3期313-315,共3页
To overcome the drawbacks such as irregular circuit construction and low system throughput that exist in conventional methods, a new factor correction scheme for coordinate rotation digital computer( CORDIC) algorit... To overcome the drawbacks such as irregular circuit construction and low system throughput that exist in conventional methods, a new factor correction scheme for coordinate rotation digital computer( CORDIC) algorithm is proposed. Based on the relationship between the iteration formulae, a new iteration formula is introduced, which leads the correction operation to be several simple shifting and adding operations. As one key part, the effects caused by rounding error are analyzed mathematically and it is concluded that the effects can be degraded by an appropriate selection of coefficients in the iteration formula. The model is then set up in Matlab and coded in Verilog HDL language. The proposed algorithm is also synthesized and verified in field-programmable gate array (FPGA). The results show that this new scheme requires only one additional clock cycle and there is no change in the elementary iteration for the same precision compared with the conventional algorithm. In addition, the circuit realization is regular and the change in system throughput is very minimal. 展开更多
关键词 coordinate rotation digital computer (CORDIC) algorithm scale factor correction field-programmable gate array (FPGA)
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Effect of radiation-induced mean wavelength shift in optical fibers on the scale factor of an interferometric fiber optic gyroscope at a wavelength of 1300 nm 被引量:7
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作者 金靖 王学勤 +1 位作者 林松 宋凝芳 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期366-372,共7页
In order to analyze the effect of wavelength-dependent radiation-induced attenuation (RIA) on the mean trans- mission wavelength in optical fiber and the scale factor of interferometric fiber optic gyroscopes (IFOG... In order to analyze the effect of wavelength-dependent radiation-induced attenuation (RIA) on the mean trans- mission wavelength in optical fiber and the scale factor of interferometric fiber optic gyroscopes (IFOGs), three types of polarization-maintaining (PM) fibers are tested by using a 60Co γ-radiation source. The observed different mean wave- length shift (MWS) behaviors for different fibers are interpreted by color-center theory involving dose rate-dependent absorption bands in ultraviolet and visible ranges and total dose-dependent near-infrared absorption bands. To evaluate the mean wavelength variation in a fiber coil and the induced scale factor change for space-borne IFOGs under low radiation doses in a space environment, the influence of dose rate on the mean wavelength is investigated by testing four germanium (Ge) doped fibers and two germanium-phosphorus (Ge-P) codoped fibers irradiated at different dose rates. Experimental results indicate that the Ge-doped fibers show the least mean wavelength shift during irradiation and their mean wavelength of optical signal transmission in fibers will shift to a shorter wavelength in a low-dose-rate radiation environment. Finally, the change in the scale factor of IFOG resulting from the mean wavelength shift is estimated and tested, and it is found that the significant radiation-induced scale factor variation must be considered during the design of space-borne IFOGs. 展开更多
关键词 space radiation fiber optic gyroscope scale factor mean wavelength
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Estimation of random errors for lidar based on noise scale factor 被引量:2
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作者 王欢雪 刘建国 张天舒 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第8期386-390,共5页
Estimation of random errors, which are due to shot noise of photomultiplier tube(PMT) or avalanche photodiode(APD) detectors, is very necessary in lidar observation. Due to the Poisson distribution of incident electro... Estimation of random errors, which are due to shot noise of photomultiplier tube(PMT) or avalanche photodiode(APD) detectors, is very necessary in lidar observation. Due to the Poisson distribution of incident electrons, there still exists a proportional relationship between standard deviation and square root of its mean value. Based on this relationship,noise scale factor(NSF) is introduced into the estimation, which only needs a single data sample. This method overcomes the distractions of atmospheric fluctuations during calculation of random errors. The results show that this method is feasible and reliable. 展开更多
关键词 atmospheric optics LIDAR random error noise factor noise scale factor
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Selecting scale factor of Bayesian multi-fidelity surrogate by minimizing posterior variance
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作者 Hongyan BU Liming SONG +1 位作者 Zhendong GUO Jun LI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第11期59-73,共15页
The Bayesian Multi-Fidelity Surrogate(MFS)proposed by Kennedy and O’Hagan(KOH model)has been widely employed in engineering design,which builds the approximation by decomposing the high-fidelity function into a scale... The Bayesian Multi-Fidelity Surrogate(MFS)proposed by Kennedy and O’Hagan(KOH model)has been widely employed in engineering design,which builds the approximation by decomposing the high-fidelity function into a scaled low-fidelity model plus a discrepancy function.The scale factor before the low-fidelity function,ρ,plays a crucial role in the KOH model.This scale factor is always tuned by the Maximum Likelihood Estimation(MLE).However,recent studies reported that the MLE may sometimes result in MFS of bad accuracy.In this paper,we first present a detailed analysis of why MLE sometimes can lead to MFS of bad accuracy.This is because,the MLE overly emphasizes the variation of discrepancy function but ignores the function waviness when selectingρ.To address the above issue,we propose an alternative approach that choosesρby minimizing the posterior variance of the discrepancy function.Through tests on a one-dimensional function,two high-dimensional functions,and a turbine blade design problem,the proposed approach shows better accuracy than or comparable accuracy to MLE,and the proposed approach is more robust than MLE.Additionally,through a comparative test on the design optimization of a turbine endwall cooling layout,the advantage of the proposed approach is further validated. 展开更多
关键词 CO-KRIGING Gaussian process regression Multi-fidelity surrogate OPTIMIZATION scale factor
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An FPGA-based LDPC decoder with optimized scale factor of NMS decoding algorithm
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作者 LI Jinming ZHAGN Pingping +1 位作者 WANG Lanzhu WANG Guodong 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2022年第4期398-406,共9页
Considering that the hardware implementation of the normalized minimum sum(NMS)decoding algorithm for low-density parity-check(LDPC)code is difficult due to the uncertainty of scale factor,an NMS decoding algorithm wi... Considering that the hardware implementation of the normalized minimum sum(NMS)decoding algorithm for low-density parity-check(LDPC)code is difficult due to the uncertainty of scale factor,an NMS decoding algorithm with variable scale factor is proposed for the near-earth space LDPC codes(8177,7154)in the consultative committee for space data systems(CCSDS)standard.The shift characteristics of field programmable gate array(FPGA)is used to optimize the quantization data of check nodes,and finally the function of LDPC decoder is realized.The simulation and experimental results show that the designed FPGA-based LDPC decoder adopts the scaling factor in the NMS decoding algorithm to improve the decoding performance,simplify the hardware structure,accelerate the convergence speed and improve the error correction ability. 展开更多
关键词 LDPC code NMS decoding algorithm variable scale factor QUANTIZATION
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First Principal Treatment of Size of Inflaton Potential, Inflaton Mass, Scale Factors, and Frequency of Emitted Radiation, Using Linde and Padmanabhan Models of Early Cosmology and BEC
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作者 Andrew Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第4期1477-1483,共7页
Using a Linde reference, as well as another one from Padmanabhan for calculation of how the early universe expands, we obtain, by default the coefficient of scale factor expansion, t to the alpha value, with alpha bei... Using a Linde reference, as well as another one from Padmanabhan for calculation of how the early universe expands, we obtain, by default the coefficient of scale factor expansion, t to the alpha value, with alpha being approximately the square root of five in value. We from there make an estimate as to the number of initial particles produced in the very beginning, which leads us to conclude that a graviton, would be a preferred initial by product. The argument as to gravitons, also reflects a choice of how the decay of initial BEC condensates of Planck sized black holes would commence, using the work produced by Chavanis, as to BEC condensates and black holes. The object will be to obtain initial frequency spread plus strength of GW production plus a suggestion as to what polarization state may be accessible from initial conditions. 展开更多
关键词 Scalar-Tensor Gravity BEC scale factor Massive Gravitons
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Modifed Multifdelity Surrogate Model Based on Radial Basis Function with Adaptive Scale Factor 被引量:5
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作者 Yin Liu Shuo Wang +3 位作者 Qi Zhou Liye Lv Wei Sun Xueguan Song 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2022年第4期93-107,共15页
Multifdelity surrogates(MFSs)replace computationally intensive models by synergistically combining information from diferent fdelity data with a signifcant improvement in modeling efciency.In this paper,a modifed MFS(... Multifdelity surrogates(MFSs)replace computationally intensive models by synergistically combining information from diferent fdelity data with a signifcant improvement in modeling efciency.In this paper,a modifed MFS(MMFS)model based on a radial basis function(RBF)is proposed,in which two fdelities of information can be analyzed by adaptively obtaining the scale factor.In the MMFS,an RBF was employed to establish the low-fdelity model.The correlation matrix of the high-fdelity samples and corresponding low-fdelity responses were integrated into an expansion matrix to determine the scaling function parameters.The shape parameters of the basis function were optimized by minimizing the leave-one-out cross-validation error of the high-fdelity sample points.The performance of the MMFS was compared with those of other MFS models(MFS-RBF and cooperative RBF)and single-fdelity RBF using four benchmark test functions,by which the impacts of diferent high-fdelity sample sizes on the prediction accuracy were also analyzed.The sensitivity of the MMFS model to the randomness of the design of experiments(DoE)was investigated by repeating sampling plans with 20 diferent DoEs.Stress analysis of the steel plate is presented to highlight the prediction ability of the proposed MMFS model.This research proposes a new multifdelity modeling method that can fully use two fdelity sample sets,rapidly calculate model parameters,and exhibit good prediction accuracy and robustness. 展开更多
关键词 Multi-fdelity surrogate RBF Adaptive scaling factor LOOCV Expansion matrix
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Behavior of a Scale Factor for Wiener Integrals of an Unbounded Function
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作者 Young Sik Kim 《Applied Mathematics》 2019年第5期326-332,共7页
The purpose of this paper is to investigate the behavior of a scale factor for Wiener integrals about the unbounded function , where {a1,a2,...,an} is an orthonormal set of elements in L2[0,T] on the Wiener space C0[0... The purpose of this paper is to investigate the behavior of a scale factor for Wiener integrals about the unbounded function , where {a1,a2,...,an} is an orthonormal set of elements in L2[0,T] on the Wiener space C0[0,T]. 展开更多
关键词 WIENER Space WIENER INTEGRAL ANALYTIC WIENER INTEGRAL ANALYTIC FEYNMAN INTEGRAL scale factor
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Behavior of a Scale Factor for Wiener Integrals and a Fourier Stieltjes Transform on the Wiener Space
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作者 Young Sik Kim 《Applied Mathematics》 2018年第5期488-495,共8页
The purpose of this paper is to investigate the behavior of a Wiener integral along the curve C of the scale factor ρ > 0 for the Wiener integral ∫C0[0,T]F(ρx)dm(x) about the function defined on the Wiener space... The purpose of this paper is to investigate the behavior of a Wiener integral along the curve C of the scale factor ρ > 0 for the Wiener integral ∫C0[0,T]F(ρx)dm(x) about the function defined on the Wiener space C0[0,T], where θ(t,u) is a Fourier-Stieltjes transform of a complex Borel measure. 展开更多
关键词 WIENER Space WIENER INTEGRAL FEYNMAN INTEGRAL ANALYTIC WIENER INTEGRAL ANALYTIC FEYNMAN INTEGRAL Fourier-Stieltjes Transform Change of scale Formula scale factor
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Anisotropic Behavior of Cosmological Models with Exponential and Hyperbolic Scale Factors
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作者 Fakhereh Md. Esmaeili 《Journal of High Energy Physics, Gravitation and Cosmology》 2018年第2期223-235,共13页
In this paper, the cosmological models of the universe are constructed in gravity with choice of the functional in the form ?and . The space-time considered here is Bianchi Type I and the energy momentum tensor is in ... In this paper, the cosmological models of the universe are constructed in gravity with choice of the functional in the form ?and . The space-time considered here is Bianchi Type I and the energy momentum tensor is in the form of perfect fluid. Two cosmological models are presented using a power form of exponential function and a hyperbolic form. The energy conditions along with the state finder diagnostic pair have been obtained and analyzed. 展开更多
关键词 f (R T ) COSMOLOGY HYPERBOLIC scale factor Bianchi Type I HUBBLE PARAMETER
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Gas Turbines Dimensions Optimization by Scale Factor Design Principle Analysis
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作者 Bendjaima Belkacem 《材料科学与工程(中英文A版)》 2017年第1期44-49,共6页
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Scale Factor Determination of Micro-Machined Angular Rate Sensors Without a Turntable 被引量:1
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作者 Gaisser Alexander 高钟毓 周斌 张嵘 陈志勇 《Tsinghua Science and Technology》 EI CAS 2006年第5期533-537,共5页
This paper presents a digital readout system to detect small capacitive signals of a micromachined angular rate sensor. The flexible parameter adjustment ability and the computation speed of the digital signal process... This paper presents a digital readout system to detect small capacitive signals of a micromachined angular rate sensor. The flexible parameter adjustment ability and the computation speed of the digital signal processor were used to develop a new calibration procedure to determine the scale factor of a gyroscope without a turntable. The force of gravity was used to deflect the movable masses in the sensor, which resulted in a corresponding angular rate input. The gyroscope scale factor was then measured without a turntable. Test results show a maximum deviation of about 1.2% with respect to the scale factor determined on a turntable with the accuracy independent of the manufacturing process and property variations The calibration method in combination with the improved readout electronics can minimize the calibration procedure and, thus, reduce the manufacturing costs. 展开更多
关键词 scale factor micro-machined angular rate sensor GYROSCOPE calibration digital readout
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Complexity and characteristic frequency studies in ECG signals of mice based on multiple scale factors 被引量:1
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作者 YANG XiaoDong HE AiJun +2 位作者 LIU Peng SUN TongFeng NING XinBao 《Science China(Life Sciences)》 SCIE CAS 2011年第6期544-552,共9页
Existing methods of physiological signal analysis based on nonlinear dynamic theories only examine the complexity difference of the signals under a single sampling frequency.We developed a technique to measure the mul... Existing methods of physiological signal analysis based on nonlinear dynamic theories only examine the complexity difference of the signals under a single sampling frequency.We developed a technique to measure the multifractal characteristic parameter intimately associated with physiological activities through a frequency scale factor.This parameter is highly sensitive to physiological and pathological status.Mice received various drugs to imitate different physiological and pathological conditions,and the distributions of mass exponent spectrum curvature with scale factors from the electrocardiogram (ECG) signals of healthy and drug injected mice were determined.Next,we determined the characteristic frequency scope in which the signal was of the highest complexity and most sensitive to impaired cardiac function,and examined the relationships between heart rate,heartbeat dynamic complexity,and sensitive frequency scope of the ECG signal.We found that all animals exhibited a scale factor range in which the absolute magnitudes of ECG mass exponent spectrum curvature achieve the maximum,and this range (or frequency scope) is not changed with calculated data points or maximal coarse-grained scale factor.Further,the heart rate of mice was not necessarily associated with the nonlinear complexity of cardiac dynamics,but closely related to the most sensitive ECG frequency scope determined by characterization of this complex dynamic features for certain heartbeat conditions.Finally,we found that the health status of the hearts of mice was directly related to the heartbeat dynamic complexity,both of which were positively correlated within the scale factor around the extremum region of the multifractal parameter.With increasing heart rate,the sensitive frequency scope increased to a relatively high location.In conclusion,these data provide important theoretical and practical data for the early diagnosis of cardiac disorders. 展开更多
关键词 ECG MULTIFRACTALITY COMPLEXITY frequency scale factor characteristic frequency
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Factor Structure and Measurement Invariance of the Japanese Version of the Mother-to-Infant Bonding Scale
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作者 Mami Yamamoto Fumie Takauma +2 位作者 Katsuhiko Tada Kaori Baba Toshinori Kitamura 《Advances in Reproductive Sciences》 2023年第4期159-170,共12页
Background: Bonding disorders affect the growth and development of infants. In Japan, the Japanese version of the Mother-to-Infant Bonding Scale (MIBS-J) is widely used for early detection of bonding disorders. Repeat... Background: Bonding disorders affect the growth and development of infants. In Japan, the Japanese version of the Mother-to-Infant Bonding Scale (MIBS-J) is widely used for early detection of bonding disorders. Repeated use of a questionnaire has problems of reduced validity. In order to correctly detect bonding disorders at multiple time points, it is necessary to confirm the measurement invariance of the scale. Baba et al. reported that invariance of the MIBS-J factor structure could only be obtained by abridging the scale into three items. Purpose: The aim of this study was to 1) confirm the factor structure and measurement invariance of the MIBS-J between two measurement times and 2) to examine factors that can be used without being affected by measurement time in order to identify item that contribute to measure met invariance. Methods: We analysed the data of 1049 and 878 mothers with a neonate collected in two waves: 5 days (Wave 1) and 1 month postpartum (Wave 2). Exploratory and confirmatory factor analyses were conducted on the data randomly divided into two groups in each wave. Results: The three-item model (MIBS-J items 1, 6, and 8) was most accepted. Measurement invariance and structural invariance were confirmed in the model. This was consistent with Baba et al.’s model. Conclusion: The three MIBS-J items showed measurement invariance and structural invariance in Japanese mothers during 1 month postpartum. 展开更多
关键词 Bonding Disorders Mother-to-Infant Bonding scale factor Analysis Measurement Invariance
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Fast-scale border collision bifurcation in SEPIC power factor pre-regulators 被引量:3
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作者 刘芳 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第7期2394-2404,共11页
In this paper we report a kind of fast-scale instability occurring in the single-ended primary inductance converter (SEPIC) power factor pre-regulator, which is designed to operate in discontinuous conduction mode. ... In this paper we report a kind of fast-scale instability occurring in the single-ended primary inductance converter (SEPIC) power factor pre-regulator, which is designed to operate in discontinuous conduction mode. Main results are given by exact cycle-by-cycle computer simulations as well as theoretical analysis. It is found that the instability phenomenon manifests itself as a fast-scale bifurcation at the switching period, which implies the occurrence of border collision bifurcation, or is related to the transition of the regular operating mode of the SEPIC. According to the theoretical analysis and simulation results, the effects of parameters on system stability, and the locations of the bifurcation points are confirmed. Moreover, the effects of such an instability on power factor and switching stress are also discussed. Finally, the occurrence of the asymmetric bifurcation locations is investigated. The results show that this work provides a convenient means of predicting stability boundaries which can facilitate the selection of the practical parameters. 展开更多
关键词 fast-scale instability border collision bifurcation SEPIC power factor pre-regulator discontinuous current mode
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Analytic Theory of Finite Asymptotic Expansions in the Real Domain. Part II-C: Constructive Algorithms for Canonical Factorizations and a Special Class of Asymptotic Scales
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作者 Antonio Granata 《Advances in Pure Mathematics》 2015年第8期503-526,共24页
This part II-C of our work completes the factorizational theory of asymptotic expansions in the real domain. Here we present two algorithms for constructing canonical factorizations of a disconjugate operator starting... This part II-C of our work completes the factorizational theory of asymptotic expansions in the real domain. Here we present two algorithms for constructing canonical factorizations of a disconjugate operator starting from a basis of its kernel which forms a Chebyshev asymptotic scale at an endpoint. These algorithms arise quite naturally in our asymptotic context and prove very simple in special cases and/or for scales with a small numbers of terms. All the results in the three Parts of this work are well illustrated by a class of asymptotic scales featuring interesting properties. Examples and counterexamples complete the exposition. 展开更多
关键词 ASYMPTOTIC EXPANSIONS CANONICAL factorIZATIONS of Disconjugate OPERATORS Algorithms for CANONICAL factorIZATIONS CHEBYSHEV ASYMPTOTIC scales
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Analytic Theory of Finite Asymptotic Expansions in the Real Domain. Part II-A: The Factorizational Theory for Chebyshev Asymptotic Scales 被引量:2
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作者 Antonio Granata 《Advances in Pure Mathematics》 2015年第8期454-480,共27页
This paper, divided into three parts (Part II-A, Part II-B and Part II-C), contains the detailed factorizational theory of asymptotic expansions of type (?)?, , , where the asymptotic scale?, , is assumed to be an ext... This paper, divided into three parts (Part II-A, Part II-B and Part II-C), contains the detailed factorizational theory of asymptotic expansions of type (?)?, , , where the asymptotic scale?, , is assumed to be an extended complete Chebyshev system on a one-sided neighborhood of . It follows two pre-viously published papers: the first, labelled as Part I, contains the complete (elementary but non-trivial) theory for;the second is a survey highlighting only the main results without proofs. All the material appearing in §2 of the survey is here reproduced in an expanded form, as it contains all the preliminary formulas necessary to understand and prove the results. The remaining part of the survey—especially the heuristical considerations and consequent conjectures in §3—may serve as a good introduction to the complete theory. 展开更多
关键词 ASYMPTOTIC EXPANSIONS FORMAL Differentiation of ASYMPTOTIC EXPANSIONS factorIZATIONS of Ordinary Differential OPERATORS CHEBYSHEV ASYMPTOTIC scales
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Reidenbach and Robin's Multidimensional Ethics Scale: Testing a Second-Order Factor Model
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作者 HowardBuchan 《Psychology Research》 2014年第10期823-834,共12页
关键词 一致性测试 子模型 二阶 道德 多维 会计师事务所 偏最小二乘 MES
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Feedback Scale因子对Burris型相对重力仪观测成果的影响 被引量:3
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作者 赵云峰 隗寿春 +3 位作者 徐云马 刘芳 祝意青 崔建中 《大地测量与地球动力学》 CSCD 北大核心 2019年第7期747-750,共4页
对3台Burris型重力仪系统中的feedback scale因子对相对重力测量成果的影响进行测试分析和研究。结果表明,feedback scale因子值与Burris型重力仪读数线性相关,且线性系数与FBK改正值有关。若feedback scale因子值产生等比例的变化,FBK... 对3台Burris型重力仪系统中的feedback scale因子对相对重力测量成果的影响进行测试分析和研究。结果表明,feedback scale因子值与Burris型重力仪读数线性相关,且线性系数与FBK改正值有关。若feedback scale因子值产生等比例的变化,FBK改正值越大,仪器读数的变化越大。在feedback scale因子值增加时,FBK改正值的正负符号决定仪器读数变化的方向。在重力值差仅有17 mGal的测段上测量时,3台Burris型重力仪基本相同的feedback scale因子变化量,得到的不同重力值差最大可相差0.140 mGal。当同一台仪器在FBK改正值分别为-14.7 mGal和2.2 mGal的2个测点进行测量时,若feedback scale因子值变化2%,测量所得重力值差的变化超过0.300 mGal。 展开更多
关键词 Burris重力仪 反馈系统 FEEDBACK scale因子 仪器读数 重力值差
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