Results 241 to 250 of about 11,068,905 (284)

PPP Performance with Large TEC Gradient and Mitigation Methods

2020 European Navigation Conference (ENC), 2020
During high-level solar activity time, frequent ionospheric irregularities lead to large total electron content (TEC) gradient. precise point positioning (PPP) performance can be significantly degraded under the unfavorable ionosphere conditions. We analyze the causes and effects of the ionosphere potential impacts on uncombined PPP (UPPP) performance ...
Yan Xiang, Wei Wang, Xin Chen, Wenxian Yun   +3 more
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Graph theory and the PPP method

Journal of Mathematical Chemistry, 1991
A graph theoretical formulation of the PPP method is presented. A weighted adjacency matrix of the PPP graph is given, wherein the off-diagonal elements are the bond orders. The automorphism group of the PPP graph is defined and shown to be isomorphic with the permutational subgroup of the permutation-inversion group of the molecule. It is demonstrated
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A new method to avoid PPP in data evaluation

Chinese Physics, 2004
The Peelle Pertinent Puzzle (PPP) has been studied systematically. The results obtained by using several proposed methods to deal with a sample of 6Li(n,t) are compared with each other. The cause of PPP occurrence has been found. A new method to avoid PPP is introduced, whose main idea is `to selectively make suitable correction for systematic error ...
Chen Zhen-Peng, Sun Ye-Ying
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A mild and efficient method to prepare oligophenylenes (PPPs)

European Polymer Journal, 2018
Abstract In the present work we developed a practical, faster, and more sustainable way to prepare conjugated materials, derived from poly-p-phenylenes (PPPs), using 10% palladium on carbon as catalyst and distilled water as solvent under microwave heating for 3 h.
Rebeca Rocha Rodrigues, Cristiano Raminelli, Laura Oliveira Péres   +2 more
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The Measurement of Wave Parameter Based on PPP Method

2013
Filtering method was selected to eliminate the impact of long-term errors which include the tide, systematic errors and other factors based on GPS Precise Point Positioning (PPP) data processing method, and accurate wave height was get finally. Fast Fourier Transform (FFT) analysis method was used to calculate average period of the wave, the average ...
Huayi Zhang, Daolong Wang, Xinghua Zhou, Yanxiong Liu   +3 more
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An excitonic method based on PPP Hamiltonian: application to the dimerization of polyenes

Synthetic Metals, 1999
Abstract Starting from the Pariser-Parr-Pople Hamiltonian, we have proposed an effective Hamiltonian based on a local description of a conjugated polymer in terms of monomers. The model is adapted to the description of the ground and low energy excited states.
Pleutin, S., Fave, J.
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Study of high-precision time transfer method enhanced by PPP-AR/PPP-RTK

Measurement Science and Technology
Abstract With the ongoing advancements in the Global Navigation Satellite System (GNSS), the technology for high-precision time transfer facilitated by GNSS has also become increasingly refined. This paper aims to investigate the contribution of information-enhanced GNSS PPP to time transfer performance, with a focus on the comprehensive
Mingyue Liu, Rui Tu, Qiushi Chen, Qi Li, Junmei Chen, Pengfei Zhang, Xiaochun Lu   +6 more
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A comparison of three PPP integer ambiguity resolution methods

GPS Solutions, 2013
Precise point positioning (PPP) integer ambiguity resolution with a single receiver can be achieved using advanced satellite augmentation corrections. Several PPP integer ambiguity resolution methods have been developed, which include the decoupled clock model, the single-difference between-satellites model, and the integer phase clock model.
Junbo Shi, Yang Gao
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PPP method for analysis of electromagnetic fields in inhomogeneous media

IEE Proceedings H Microwaves, Antennas and Propagation, 1993
A perturbation/iterative method (the PPP method) is proposed for the analysis of electromagnetic fields in inhomogeneous media. It consists of increasing the values of the parameters the medium at all points in small increments, starting from their vacuum values, and computing the induced sources by means of the total field (the incident field, plus ...
B.D. Popović, B.M. Notaroš
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Analysis of Velocity Estimation Methods Based on BDS PPP

2019
Position difference, Doppler observation and time-differenced carrier phase (TDCP) are three commonly used velocity estimation methods. Since the average velocity of two epochs is obtained both in the position difference and TDCP velocity estimation, the accuracy is affected by the carrier’s kinematics, large deviation will appear in high dynamic ...
Shunli Duan, Wei Sun, Junbo Shi, Chenhao Ouyang   +3 more
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