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Accuracy estimation of site coordinates derived from GNSS-observations by non-classical error theory of measurements
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作者 Petro Dvulit Stepan Savchuk Iryna Sosonka 《Geodesy and Geodynamics》 CSCD 2021年第5期347-355,共9页
The velocities of tectonic plates derived from GNSS time series are regularly used as input data for geophysical models. However, as shown by numerous researches, the coordinates time series contain residual errors of... The velocities of tectonic plates derived from GNSS time series are regularly used as input data for geophysical models. However, as shown by numerous researches, the coordinates time series contain residual errors of a systematic nature, which can significantly affect the reliability of the obtained velocity estimates. This research shows that using non-classical error theory of measurement(NETM)for processing GNSS time series allows detecting the presence of weak, not removed from GNSS processing, sources of systematic errors. Based on the coordinate time series of selected permanent GNSS stations in Europe, we checked the empirical distributions of errors by the NETM on G. Jeffries’ recommendations and on the principles of the theory of hypothesis tests according to Pearson’s criterion. It is established that the obtained coordinates time series of GNSS-stations only partially confirm the hypothesis of their conformity to the normal Gaussian distribution law, and this may be the main reason for their unrepresentative classification. In the future, it is necessary to identify and take into account the causes of residual errors that distort the real distribution of the results of the GNSS time series. 展开更多
关键词 GNSS data Processing GNSS time Series Discontinuities in time series Non-classical error theory of measurements Noise analysis
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Optimal phase estimation with photon-number difference measurement using twin-Fock states of light 被引量:2
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作者 徐佳慧 王建中 +2 位作者 陈爱喜 李勇 金光日 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第12期82-87,共6页
Quantum phase measurement with multiphoton twin-Fock states has been shown to be optimal for detecting equal numbers of photons at the output ports of a Mach–Zehnder interferometer(i.e., the so-called single-fringe d... Quantum phase measurement with multiphoton twin-Fock states has been shown to be optimal for detecting equal numbers of photons at the output ports of a Mach–Zehnder interferometer(i.e., the so-called single-fringe detection), since the phase sensitivity can saturate the quantum Cramér–Rao lower bound at certain values of phase shift. Here we report a further step to achieve a global phase estimation at the Heisenberg limit by detecting the particle-number difference(i.e., the ?_z measurement). We show the role of experimental imperfections on the ultimate estimation precision with the six-photon twin-Fock state of light. Our results show that both the precision and the sensing region of the ?_z measurement are better than those of the single-fringe detection, due to combined contributions of the measurement outcomes. We numerically simulate the phase estimation protocol using an asymptotically unbiased maximum likelihood estimator. 展开更多
关键词 foundations of quantum mechanics measurement theory nonclassical interferometry
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Bell’s Theorem and Einstein’s Worry about Quantum Mechanics
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作者 Han Geurdes 《Journal of Quantum Information Science》 2023年第3期131-137,共7页
With the use of a local dependency on instrument setting parameters of the probability density of local hidden variables, it is demonstrated that a Kolmogorov formulation reproduces the quantum correlation. This is th... With the use of a local dependency on instrument setting parameters of the probability density of local hidden variables, it is demonstrated that a Kolmogorov formulation reproduces the quantum correlation. This is the novelty of the work. In a Bell experiment, one cannot distinguish between Bell’s formula and the here presented local Kolmogorov formula. With the presented formula, no CHSH can be obtained. Therefore, the famous CHSH inequality has no excluding power concerning local extra Einstein parameter models. This result concurs with other previous research concerning difficulties with Bell’s formula. 展开更多
关键词 Bell’s Correlation Formula Basic Measure theory
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ON STATIONARY HYPERSURFACES IN EUCLIDEAN SPACES 被引量:1
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作者 赵培标 杨孝平 《Acta Mathematica Scientia》 SCIE CSCD 2006年第2期349-357,共9页
Some techniques in the Geometric Measure Theory are used to study the hypersurfaces in Euclidean spaces and some fundamental properties with this subject are discussed in this article.
关键词 Stable hypersurfaces Geometric Measure theory the first and second variation mean curvature
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ESTIMATES FOR THE MAXIMAL SINGULAR INTEGRALS WITHOUT DOUBLING CONDITION 被引量:1
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作者 Ruan Jianmiao Zhu Xiangrong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第4期448-454,共7页
It is shown that the maximal singular integral operator with kernels satisfying Ho rmander's condition is of weak type (1,1) and L^p (1〈p〈∞) bounded without assuming that the underlying measure p is doubling. ... It is shown that the maximal singular integral operator with kernels satisfying Ho rmander's condition is of weak type (1,1) and L^p (1〈p〈∞) bounded without assuming that the underlying measure p is doubling. Under stronger smoothness conditions,such estimates can be obtained by using a Cotlar's inequality. This inequality is not applicable here and it is noticeable that the Cotlar's inequality maybe fails under Hormander's condition. 展开更多
关键词 Calderon-Zygmund theory maximal singular integral nondoubling measure.
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THE GAUSS–GREEN THEOREM IN CLIFFORD ANALYSIS AND ITS APPLICATIONS
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作者 罗纬宇 杜金元 《Acta Mathematica Scientia》 SCIE CSCD 2015年第1期235-254,共20页
In this article, we establish the Gauss Green type theorems for Clifford-valued functions in Clifford analysis. The boundary conditions in theorems obtained are very general by using the geometric measure theoretic me... In this article, we establish the Gauss Green type theorems for Clifford-valued functions in Clifford analysis. The boundary conditions in theorems obtained are very general by using the geometric measure theoretic method. The Cauchy-Pompeiu formula for Clifford-valued functions under the weak condition will be derived as their simple application. Furthermore, Cauchy formula for monogenic functions under the weak condition is derived directly from the Cauchy-Pompeiu formula. 展开更多
关键词 Gauss Green theorem Cauchy's theorem Cauchy-Pompeiu formula Clifford analysis Geometric measure theory
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Coseismic gravity and displacement changes of Japan Tohoku earthquake(Mw 9.0) 被引量:1
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作者 Xinlin Zhang Shuhei Okubo +1 位作者 Yoshiyuki Tanaka Hui Li 《Geodesy and Geodynamics》 2016年第2期95-100,共6页
The greatest earthquake in the modern history of Japan and probably the fourth greatest in the last 100 years in the world occurred on March 11, 2011 off the Pacific coast of Tohoku.Large tsunami and ground motions ca... The greatest earthquake in the modern history of Japan and probably the fourth greatest in the last 100 years in the world occurred on March 11, 2011 off the Pacific coast of Tohoku.Large tsunami and ground motions caused severe damage in wide areas, particularly many towns along the Pacific coast. So far, gravity change caused by such a great earthquake has been reported for the 1964 Alaska and the 2010 Maule events. However, the spatial-temporal resolution of the gravity data for these cases is insufficient to depict a co-seismic gravity field variation in a spatial scale of a plate subduction zone. Here, we report an unequivocal co-seismic gravity change over the Japanese Island, obtained from a hybrid gravity observation(combined absolute and relative gravity measurements). The time interval of the observation before and after the earthquake is within 1 year at almost all the observed sites, including 13 absolute and 16 relative measurement sites, which deduced tectonic and environmental contributions to the gravity change. The observed gravity agrees well with the result calculated by a dislocation theory based on a self-gravitating and layered spherical earth model. In this computation, a co-seismic slip distribution is determined by an inversion of Global Positioning System(GPS) data. Of particular interest is that the observed gravity change in some area is negative where a remarkable subsidence is observed by GPS, which can not be explained by simple vertical movement of the crust. This indicated that the mass redistribution in the underground affects the gravity change. This result supports the result that Gravity Recovery and Climate Experiment(GRACE) satellites detected a crustal dilatation due to the 2004 Sumatra earthquake by the terrestrial observation with a higher spatial and temporal resolution. 展开更多
关键词 Tohoku earthquake(Mw 9.0) Co-seismic gravity change Co-seismic displacement change Coseismic geoid change Dislocation theory Global Positioning System Absolute gravity measurement Relative gravity measurement
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Theoretical Design of a 104MHz Ladder Type IH-RFQ Accelerator
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作者 聂元存 陆元荣 +5 位作者 陈佳洱 颜学庆 高淑丽 朱昆 刘克新 郭之虞 《Chinese Physics Letters》 SCIE CAS CSCD 2010年第11期47-50,共4页
Beam dynamics and rf designs of a 104 MHz ladder type IH-RFQ (L-IH-RFQ) accelerator are finished at Peking University for the acceleration of 14C+ from 40 keV to 500 keV. As a specific feature, the output beam ener... Beam dynamics and rf designs of a 104 MHz ladder type IH-RFQ (L-IH-RFQ) accelerator are finished at Peking University for the acceleration of 14C+ from 40 keV to 500 keV. As a specific feature, the output beam energy spread is as low as 0.6% achieved with the internal discrete bunching method, which makes potential applications of RFQ feasible, such as accelerator mass spectrometry and ion implantation. Tolerances of the beam dynamics design are studied by means of changing the input beam parameters, and the results are quite satisfying. On the other hand, the L-IH-RFQ structure is employed, taking advantage of its mechanical stability and the absence of inter-electrode voltage asymmetry. Radio-frequency properties are studied and optimized for reducing power loss with Microwave Studio (MWS). Tuning of the field flatness and frequency is investigated in principle. 展开更多
关键词 ACCELERATORS beams and electromagnetism Nuclear physics Instrumentation and measurement Particle physics and field theory
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Success and Incoherence of Orthodox Quantum Mechanics 被引量:1
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作者 M. E. Burgos 《Journal of Modern Physics》 2016年第12期1449-1454,共6页
Orthodox quantum mechanics is a highly successful theory despite its serious conceptual flaws. It renounces realism, implies a kind of action-at-a-distance and is incompatible with determinism. Orthodox quantum mechan... Orthodox quantum mechanics is a highly successful theory despite its serious conceptual flaws. It renounces realism, implies a kind of action-at-a-distance and is incompatible with determinism. Orthodox quantum mechanics states that Schr&oumldinger’s equation (a deterministic law) governs spontaneous processes while measurement processes are ruled by probability laws. It is well established that time dependent perturbation theory must be used for solving problems involving time. In order to account for spontaneous processes, this last theory makes use of laws valid only when measurements are performed. This incoherence seems absent from the literature. 展开更多
关键词 Quantum measurements—Time Dependent Perturbation theory
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Assessment of Primordial Radionuclides in Pakistani Red Bricks and Associated Radiation Doses
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作者 K. Khan A. Jabbar +2 位作者 P. Akhter M. Tufail H. M. Khan 《Chinese Physics Letters》 SCIE CAS CSCD 2010年第3期343-346,共4页
Specific activity of primordial radionuclides and associated radiation hazards due to 40K, 226Ra, and 232Th have been measured in backed red brick samples, collected from five highly populated areas of the North West ... Specific activity of primordial radionuclides and associated radiation hazards due to 40K, 226Ra, and 232Th have been measured in backed red brick samples, collected from five highly populated areas of the North West Frontier Province of Pakistan. For the detection, analysis and data acquisition, a high purity germanium detector was used. Associated external doses were calculated using a Monte Carlo neutron photon transport code. A theoretical model to determine the gamma dose rate at 1 m height from the floor, made of bricks, was employed for the calculation of mass attenuation coefficient and self-absorption in the floor for the gamma energies of these radionuclides and their progeny. Monte Carlo simulation shows that in this study the floor, having more than an effective thickness of 15 cm, contributes very little to the external gamma dose rate. The values of the external dose rate and annual effective dose are found to be much lower than the world average as well as from other countries of the world. 展开更多
关键词 ACCELERATORS beams and electromagnetism Nuclear physics Instrumentation and measurement Environmental and Earth science Particle physics and field theory Astrophysics and astroparticles
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Evaluating 3D position and velocity of subject in parabolic flight experiment by use of the binocular stereo vision measurement 被引量:6
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作者 金涛 贾宏志 +6 位作者 侯文玫 Ryo Yamamoto Norihiro Nagai Yusaku Fujii Koichi Maru Naoya Ohta Kazuhito Shimada 《Chinese Optics Letters》 SCIE EI CAS CSCD 2010年第6期601-605,共5页
A practical method for evaluating the three-dimensional(3D) position and velocity of a moving object used in the parabolic flight experiment is developed by using the binocular stereo vision measurement theory. The ... A practical method for evaluating the three-dimensional(3D) position and velocity of a moving object used in the parabolic flight experiment is developed by using the binocular stereo vision measurement theory. The camera calibration mathematic model without considering the lens distortion is introduced.The direct linear transformation(DLT) algorithm is improved to accomplish the camera calibration.The camera calibration result and optimization algorithm are used to calculate the object's world coordinate from image coordinate.The 3D position and the velocity of the moving object are obtained.The standard uncertainty in estimating the velocity is 0.0024 m/s,which corresponds to 1%level of the velocity of the object in the experiment.The results show that this method is very useful for the parabolic flight experiments. 展开更多
关键词 BINOCULARS Calibration Cameras EXPERIMENTS Linear transformations measurement theory Three dimensional Uncertainty analysis VELOCITY
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Stochastic Nicholson's blowflies model with delays
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作者 Nadia Belmabrouk Mondher Damak Mohsen Miraoui 《International Journal of Biomathematics》 SCIE 2023年第1期97-128,共32页
In this research work,we introduce a new concept of double measure ergodic processes to identify the space of double measure pseudo almost periodic(or pap)processes in the pth mean sense.We display some findings regar... In this research work,we introduce a new concept of double measure ergodic processes to identify the space of double measure pseudo almost periodic(or pap)processes in the pth mean sense.We display some findings regarding the completeness as well as the composition theorems and the invariance of the space consisting in double measure pap processes.Motivated by the above-mentioned results,the Banach fixed point theorem and the stochastic analysis techniques,we prove the existence,uniqueness and the global exponential stability of doubly measure pseudo almost periodic mild solution for a class of stochastic Nicholson's blowflies model with mixed delays in a separable real Hilbert space.The concluding part of the work is crowned with an example to confirm the reliability and feasibility of our findings. 展开更多
关键词 Pseudo almost periodic solution measure theory fixed point theorem stochastic Nicholson's blowflies model
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Estimation of measuring uncertainty for optical micro-coordinate measuring machine 被引量:1
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作者 宋康 蒋庄德 《Chinese Optics Letters》 SCIE EI CAS CSCD 2004年第12期704-707,共4页
Based on the evaluation principle of the measuring uncertainty of the traditional coordinate measuring machine (CMM), the analysis and evaluation of the measuring uncertainty for optical micro-CMM have been made. Opti... Based on the evaluation principle of the measuring uncertainty of the traditional coordinate measuring machine (CMM), the analysis and evaluation of the measuring uncertainty for optical micro-CMM have been made. Optical micro-CMM is an integrated measuring system with optical, mechanical, and electronic components, which may influence the measuring uncertainty of the optical micro-CMM. If the influence of laser speckle is taken into account, its longitudinal measuring uncertainty is 2.0 μm, otherwise it is 0.88 μm. It is proved that the estimation of the synthetic uncertainty for optical micro-CMM is correct and reliable by measuring the standard reference materials and simulating the influence of the diameter of laser beam. With Heisenberg's uncertainty principle and quantum mechanics theory, a method for improving the measuring accuracy of optical micro-CMM through adding a diaphragm in the receiving terminal of the light path was proposed, and the measuring results are verified by experiments. 展开更多
关键词 Coordinate measuring machines DIAPHRAGMS Laser beams measurement theory measurementS Optical instruments SPECKLE
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Study on eight-pass dual-frequency laser interferometer with nanometer precision
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作者 高海军 程兆谷 +2 位作者 宁志高 崔品静 黄惠杰 《Chinese Optics Letters》 SCIE EI CAS CSCD 2005年第9期513-515,共3页
A new dual-frequency laser displacement measurement interferometer with nanometer precision has been developed. An eight-pass optical subdivision technology is proposed to improve resolution based on commercial interf... A new dual-frequency laser displacement measurement interferometer with nanometer precision has been developed. An eight-pass optical subdivision technology is proposed to improve resolution based on commercial interferometers. A static positioning error measuring method has been used to examine the precision and repeatability of the laser interferometer. An optical resolution of 1.24 nm and an accuracy of nanometer scale have been achieved. 展开更多
关键词 Information technology measurement errors measurement theory Optical instruments
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