Theoretical analysis of the multi-GNSS contribution to partial ambiguity estimation and R-ratio test-based ambiguity validation

A series of fatigue crack growth rate tests was conducted in order to study the effects of negative stress ratio upon the fatigue crack growth rate of low-alloy steel in air environment. The tests used four-point bend specimens in order to simulate linear stress distributions typical of many pressure vessel applications. This type of testing adds to the knowledge on negative stress ratio effects for low-alloy steels that in the past have been obtained from uniform tension-compression tests. Additionally, the applied bending stress range was varied from low values of applied stress to high values of applied stress over twice the yield strength. Load control was used for tests for which the stress range was less than twice the yield strength and deflection control was used for the higher stress range tests. The crack geometries involved were both short and long fatigue cracks started at notches and tight fatigue cracks for which crack closure could occur over the full crack face. The results are presented in terms of the stress intensity factor ratio R = KMIN/KMAX. The negative R-ratio test results were correlated to an equation of the form da/dN = C[ΔK/(A−R)]n where A, C, and n are curve-fitting parameters. It was found that the effects of negative R-ratio on the fatigue crack growth rates for even the high stress range tests could be bounded by correlating the foregoing equation to only positive R-ratio test results and extending the resulting equation into the negative R-ratio regime.

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Ambiguity validation with combined ratio test and ellipsoidal integer aperture estimator

Journal of Geodesy ◽

10.1007/s00190-010-0400-8 ◽

2010 ◽

Vol 84 (10) ◽

pp. 597-604 ◽

Cited By ~ 17

Author(s):

Shengyue Ji ◽

Wu Chen ◽

Xiaoli Ding ◽

Yongqi Chen ◽

Chunmei Zhao ◽

...

Keyword(s):

Ratio Test ◽

Ambiguity Validation ◽

Integer Aperture Estimator

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Integer Ambiguity Fixation Based on SC-PAR Algorithm

Journal of Physics Conference Series ◽

10.1088/1742-6596/2083/4/042093 ◽

2021 ◽

Vol 2083 (4) ◽

pp. 042093

Author(s):

Xizi Jia ◽

Yuanfa Ji ◽

Wentao Fu ◽

Weibin Liang ◽

Bingye Pan

Keyword(s):

Signal To Noise Ratio ◽

Attenuation Factor ◽

Elevation Angle ◽

Integer Ambiguity ◽

Single Frequency ◽

Fixed Rate ◽

R Ratio ◽

Geometric Precision ◽

Ambiguity Estimation ◽

Satellite Signal

Abstract In terms of quality control of ambiguity estimation, the common partial ambiguity fixation algorithm is improved, and the SC-PAR (Single frequency Combined Partial Ambiguity Resolution) algorithm is proposed. After the algorithm fails to fix the full ambiguity, it filters the ambiguity subset step by step according to the number of continuous satellite lock epochs, satellite elevation angle, satellite signal-to-noise ratio, geometric precision factor, ambiguity variance and ambiguity precision attenuation factor, and searches Optimal ambiguity subset. According to the R-ratio value and the success rate index, the search results are jointly tested, and the remaining subsets are corrected with the subsets that pass the test. The results show that compared with the FAR and conventional PAR algorithms, the fixed rate of the SC-PAR algorithm is increased by 65.01% and 27.97%, respectively, and the accuracy is also significantly improved.

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Microdiffraction Patterns of Small Metallic Particles II; Theoretical Analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055680 ◽

1982 ◽

Vol 40 ◽

pp. 668-669

Author(s):

A. Gómez ◽

P. Schabes-Retchkiman ◽

M. José-Yacamán ◽

T. Ocaña

Keyword(s):

Experimental Data ◽

Electron Diffraction ◽

Theoretical Analysis ◽

Size Range ◽

Dynamical Theory ◽

Metallic Particles ◽

Splitting Effect

The splitting effect that is observed in microdiffraction pat-terns of small metallic particles in the size range 50-500 Å can be understood using the dynamical theory of electron diffraction for the case of a crystal containing a finite wedge. For the experimental data we refer to part I of this work in these proceedings.

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A likelihood ratio test for detecting patterns of disease-marker association

Annals of Human Genetics ◽

10.1017/s0003480097006349 ◽

1997 ◽

Vol 61 (4) ◽

pp. 335-350 ◽

Cited By ~ 28

Author(s):

A. P. MORRIS ◽

J. C. WHITTAKER ◽

R. N. CURNOW

Keyword(s):

Likelihood Ratio ◽

Likelihood Ratio Test ◽

Ratio Test ◽

Disease Marker

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Theoretical analysis of a monopole antenna with conducting flat disk above the earth

Electronics and Communications in Japan (Part I Communications) ◽

10.1002/ecja.1021.abs ◽

2001 ◽

Vol 84 (7) ◽

pp. 27-36

Author(s):

Aki Yuasa ◽

Daisuke Itatsu ◽

Naoki Inagaki ◽

Nobuyoshi Kikuma

Keyword(s):

Theoretical Analysis ◽

Monopole Antenna ◽

The Earth ◽

Flat Disk

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Context Aversion, Pavlovian Conditioning, and the Psychological Side Effects of Chemotherapy

European Psychologist ◽

10.1027/1016-9040.2.118 ◽

1997 ◽

Vol 2 (2) ◽

pp. 118-124

Author(s):

Geoffrey Hall

Keyword(s):

Animal Model ◽

Side Effects ◽

Theoretical Analysis ◽

Conditioned Response ◽

Behavioral Strategies ◽

Contextual Cues ◽

Anticipatory Nausea ◽

Laboratory Rats ◽

Anticipatory Nausea And Vomiting ◽

Parallel Case

Patients who have undergone several sessions of chemotherapy for cancer will sometimes develop anticipatory nausea and vomiting (ANV), these unpleasant side effects occurring as the patients return to the clinic for a further session of treatment. Pavlov's analysis of learning allows that previously neutral cues, such as those that characterize a given place or context, can become associated with events that occur in that context. ANV could thus constitute an example of a conditioned response elicited by the contextual cues of the clinic. In order to investigate this proposal we have begun an experimental analysis of a parallel case in which laboratory rats are given a nausea-inducing treatment in a novel context. We have developed a robust procedure for assessing the acquisition of context aversion in rats given such training, a procedure that shows promise as a possible animal model of ANV. Theoretical analysis of the conditioning processes involved in the formation of context aversions in animals suggests possible behavioral strategies that might be used in the alleviation of ANV, and we report a preliminary experimental test of one of these.

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