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Load Statistics Priority Random Access Technology Based on Air-Space-Ground Integrated Network
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作者 Enze Li Hao Huan +1 位作者 Jingyu Wang Kunshan Yang 《Journal of Beijing Institute of Technology》 EI CAS 2024年第6期493-506,共14页
In today's world where everything is interconnected, air-space-ground integrated networks have become a current research hotspot due to their characteristics of high, long and wide area coverage. Given the constan... In today's world where everything is interconnected, air-space-ground integrated networks have become a current research hotspot due to their characteristics of high, long and wide area coverage. Given the constantly changing and dynamic characteristics of air and space networks, along with the sheer number and complexity of access nodes involved, the process of rapid networking presents substantial challenges. In order to achieve rapid and dynamic networking of air-space-ground integrated networks, this paper focuses on the study of methods for large-scale nodes to randomly access satellites. This paper utilizes a cross-layer design methodology to enhance the access success probability by jointly optimizing the physical layer and medium access control(MAC) layer aspects. Load statistics priority random access(LSPRA) technology is proposed.Experiments show that when the number of nodes is greater than 1 000, this method can also ensure stable access performance, providing ideas for the design of air-space-ground integrated network access systems. 展开更多
关键词 air-space-ground integrated network random access satellite-to-ground statistics priority access success probability
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THE LAW OF ITERATED LOGARITHM FOR R/S STATISTICS 被引量:5
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作者 林正炎 《Acta Mathematica Scientia》 SCIE CSCD 2005年第2期326-330,共5页
A law of iterated logarithm for R/S statistics with the help of the strong approximations of R/S statistics by functions of a Wiener process is shown.
关键词 R/S statistics law of iterated logarithm strong approximation
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New Dynamic Algorithm for IRFPA Bad Pixel Detection and Compensation Based on Statistics 被引量:4
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作者 刘崇亮 金伟其 +1 位作者 曹扬 刘秀 《Journal of Beijing Institute of Technology》 EI CAS 2009年第4期463-467,共5页
Based on the analysis to the behavior of bad pixels, a statistics-based auto-detecting and compensation algorithm for bad pixels is proposed. The correcting process is divided into two stages: bad pixel detection and... Based on the analysis to the behavior of bad pixels, a statistics-based auto-detecting and compensation algorithm for bad pixels is proposed. The correcting process is divided into two stages: bad pixel detection and bad pixel compensation. The proposed detection algorithm is a combination of median filtering and statistic method. Single frame median filtering is used to locate approximate map, then statistic method and threshold value is used to get the accurate location map of bad pixels. When the bad pixel detection is done, neighboring pixel replacement algorithm is used to compensate them in real-time. The effectiveness of this approach is test- ed by applying it to I-IgCATe infrared video. Experiments on real infrared imaging sequences demonstrate that the proposed algorithm requires only a few frames to obtain high quality corrections. It is easy to combine with traditional static methods, update the pre-defined location map in real-time. 展开更多
关键词 infrared focal plane array (IRFPA) based on statistics bad pixel detection bad pixel compensation
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Statistics of extreme events in Chinese stock markets 被引量:1
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作者 吴干华 邱路 +4 位作者 Mutua Stephen 李信利 杨悦 杨会杰 蒋艳 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期573-577,共5页
We investigate the impact of financial factors on daily volume recurrent time intervals in the developing Chinese stock markets. The tails of probability distribution functions(PDFs) of volume recurrent intervals be... We investigate the impact of financial factors on daily volume recurrent time intervals in the developing Chinese stock markets. The tails of probability distribution functions(PDFs) of volume recurrent intervals behave as a power-law, and the scaling exponent decreases with the increase of stock lifetime, which are similar to those in the US stock markets, and they are typical representatives of developed markets. The difference is that the power-law exponent values remain almost the same with the changes of market capitalization, mean volume, and mean trading value, respectively. These findings enrich the results for event statistics for financial markets. 展开更多
关键词 extreme statistics recurrent time interval volume volatility
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MAXIMUM TEST FOR A SEQUENCE OF QUADRATIC FORM STATISTICS ABOUT SCORE TEST IN LOGISTIC REGRESSION MODEL 被引量:1
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作者 Qing YANG Jiayan ZHU Zhengbang LI 《Acta Mathematica Scientia》 SCIE CSCD 2020年第2期543-556,共14页
This article proposes the maximum test for a sequence of quadratic form statistics about score test in logistic regression model which can be applied to genetic and medicine fields.Theoretical properties about the max... This article proposes the maximum test for a sequence of quadratic form statistics about score test in logistic regression model which can be applied to genetic and medicine fields.Theoretical properties about the maximum test are derived.Extensive simulation studies are conducted to testify powers robustness of the maximum test compared to other two existed test.We also apply the maximum test to a real dataset about multiple gene variables association analysis. 展开更多
关键词 Maximum test quadratic form statistics score test asymptotic statistical property
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Application of artificial neural networks and multivariate statistics to estimate UCS using textural characteristics 被引量:15
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作者 Amin Manouchehrian Mostafa Sharifzadeh Rasoul Hamidzadeh Moghadam 《International Journal of Mining Science and Technology》 SCIE EI 2012年第2期229-236,共8页
Before any rock engineering project,mechanical parameters of rocks such as uniaxial compressive strength and young modulus of intact rock get measured using laboratory or in-situ tests,but in some situations preparing... Before any rock engineering project,mechanical parameters of rocks such as uniaxial compressive strength and young modulus of intact rock get measured using laboratory or in-situ tests,but in some situations preparing the required specimens is impossible.By this time,several models have been established to evaluate UCS and E from rock substantial properties.Artificial neural networks are powerful tools which are employed to establish predictive models and results have shown the priority of this technique compared to classic statistical techniques.In this paper,ANN and multivariate statistical models considering rock textural characteristics have been established to estimate UCS of rock and to validate the responses of the established models,they were compared with laboratory results.For this purpose a data set for 44 samples of sandstone was prepared and for each sample some textural characteristics such as void,mineral content and grain size as well as UCS were determined.To select the best predictors as inputs of the UCS models,this data set was subjected to statistical analyses comprising basic descriptive statistics,bivariate correlation,curve fitting and principal component analyses.Results of such analyses have shown that void,ferroan calcitic cement,argillaceous cement and mica percentage have the most effect on USC.Two predictive models for UCS were developed using these variables by ANN and linear multivariate regression.Results have shown that by using simple textural characteristics such as mineral content,cement type and void,strength of studied sandstone can be estimated with acceptable accuracy.ANN and multivariate statistical UCS models,revealed responses with 0.87 and 0.76 regressions,respectively which proves higher potential of ANN model for predicting UCS compared to classic statistical models. 展开更多
关键词 Textural characteristicsUniaxial compressive strengthPredictive modelsArtificial neural networksMultivariate statistics
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The p-value and model specification in statistics 被引量:1
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作者 Bokai Wang Zhirou Zhou +2 位作者 Hongyue Wang Xin M Tu Changyong Feng 《General Psychiatry》 CSCD 2019年第3期163-166,共4页
SUMMARY The p value has been widely used as a way to summarise the significance in data analysis. However, misuse and misinterpretation of the p value is common in practice. Our result shows that if the model specific... SUMMARY The p value has been widely used as a way to summarise the significance in data analysis. However, misuse and misinterpretation of the p value is common in practice. Our result shows that if the model specification is wrong, the distribution of the p value may be inappropriate, which makes the decision based on the p value invalid. 展开更多
关键词 P-VALUE MODEL SPECIFICATION statistics
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Photon statistics of pulse-pumped four-wave mixing in fiber with weak signal injection 被引量:1
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作者 刘楠楠 刘宇宏 +1 位作者 李嘉敏 李小英 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第7期229-233,共5页
We study the photon statistics of pulse-pumped four-wave mixing in fibers with weak coherent signal injection by measuring the intensity correlation functions of individual signal and idler fields. The experimental re... We study the photon statistics of pulse-pumped four-wave mixing in fibers with weak coherent signal injection by measuring the intensity correlation functions of individual signal and idler fields. The experimental results show that the intensity correlation function of individual signal(idler) field g_(s(i))^(2) decreases with the intensity of signal injection. After applying narrow band filter in signal(idler) band, the value of g_(s(i))^(2) decreases from 1.9 ± 0.02(1.9 ± 0.02) to 1.03 ± 0.02(1.05 ± 0.02) when the intensity of signal injection varies from 0 to 120 photons/pulse. The results indicate that the photon statistics changes from Bose–Einstein distribution to Poisson distribution. We calculate the intensity correlation functions by using the multi-mode theory of four-wave mixing in fibers. The theoretical curves well fit the experimental results.Our investigation will be useful for mitigating the crosstalk between quantum and classical channels in a dense wavelength division multiplexing network. 展开更多
关键词 photon statistics four-wave mixing intensity correlation function fiber optics
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Aperture-averaged scintillation index and fade statistics in weak oceanic turbulence 被引量:1
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作者 Hao Wang Fu-Zeng Kang +2 位作者 Xuan Wang Wei Zhao Shu-Wei Sun 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第6期320-328,共9页
With the rapid demand for underwater optical communication(UOC), studies of UOC degradation by oceanic turbulence have attached increasing attention worldwide and become a research hot-spot in recent years. Previous s... With the rapid demand for underwater optical communication(UOC), studies of UOC degradation by oceanic turbulence have attached increasing attention worldwide and become a research hot-spot in recent years. Previous studies used a simplified and inaccurate oceanic turbulence spectrum, in which the eddy diffusivity ratio between temperature and salinity is assumed to be unity and the outer scale of turbulence is assumed to be infinite. However, both assumptions are not true in most of the actual marine environments. In this paper, based on the Rytov theory in weak turbulence, we derive analytical expressions of "the aperture-averaged scintillation index"(SI) for both plane and spherical waves, which can clearly demonstrate how SI is influenced by several key factors in UOC. Then, typical fade statistics of the UOC system in weak turbulence is discussed including the probability of fade, the expected number of fades per time, the mean fade time,signal-to-noise ratio and bit error rate. Our results show that spherical wave is preferable in the UOC system in weak turbulence compared to plane wave, and the aperture-averaged effect has a significant impact on UOC system's performance.Our results can be used to determine those key parameters for designing the UOC system over reasonable ranges. 展开更多
关键词 underwater optical communication(UOC) aperture-averaged scintillation index fade statistics
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Collision statistics of clusters:from Poisson model to Poisson mixtures
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作者 Sascha Vongehr 唐少春 孟祥康 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第2期225-233,共9页
Clusters traverse a gas and collide with gas particles. The gas particles are absorbed, and the clusters become hosts. If the clusters are size-selected, the number of guests will be Poisson distributed. We review thi... Clusters traverse a gas and collide with gas particles. The gas particles are absorbed, and the clusters become hosts. If the clusters are size-selected, the number of guests will be Poisson distributed. We review this by showcasing four laboratory procedures that all rely on the validity of the Poisson model. The effects of a statistical distribution of the clusters' sizes in a beam of clusters are discussed. We derive the average collision rates. Additionally, we present Poisson mixture models that also involve standard deviations. We derive the collision statistics for common size distributions of hosts and also for some generalizations thereof. The models can be applied to large noble gas clusters traversing doping gas. While outlining how to fit a generalized Poisson to the statistics, we still find even these Poisson models to be often insufficient. 展开更多
关键词 collision statistics helium droplets CLUSTERS Poisson statistics
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Testing Result Statistics-Based Rapid Testing Method for Safety-Critical System 被引量:1
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作者 Zhi-Yao Deng Nan Sang 《Journal of Electronic Science and Technology of China》 2008年第3期338-341,共4页
Safety-critical system (SCS) has highly demand for dependability, which requires plenty of resource to ensure that the system under test (SUT) satisfies the dependability requirement. In this paper, a new SCS rapi... Safety-critical system (SCS) has highly demand for dependability, which requires plenty of resource to ensure that the system under test (SUT) satisfies the dependability requirement. In this paper, a new SCS rapid testing method is proposed to improve SCS adaptive dependability testing. The result of each test execution is saved in calculation memory unit and evaluated as an algorithm model. Then the least quantity of scenario test case for next test execution will be calculated according to the promised SUT's confidence level. The feedback data are generated to weight controller as the guideline for the further testing. Finally, a compre- hensive experiment study demonstrates that this adaptive testing method can really work in practice. This rapid testing method, testing result statistics-based adaptive control, makes the SCS dependability testing much more effective. 展开更多
关键词 ADAPTIVE FEEDBACK safety-critical system statistics TEST
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Statistics 被引量:5
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作者 National Bureau of Statistics of China 《China Textile》 2013年第1期59-61,共3页
关键词 statistics
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Tuning the intensity statistics of random speckle patterns
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作者 Fan Meng Yue Zhao +1 位作者 Yun-Zuo Zhang Lei Huo 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第5期327-331,共5页
Speckle patterns are a fundamental tool in a variety of physical and optical applications. Here, we investigate a method of precisely tuning the intensity statistics of random speckle patterns into a desirable pattern... Speckle patterns are a fundamental tool in a variety of physical and optical applications. Here, we investigate a method of precisely tuning the intensity statistics of random speckle patterns into a desirable pattern that possesses the same spatial correlation length and similar statistics distribution. This tuning mechanism relies on the derivation of the transform function and transmission matrix, which achieves different contrasts while maintaining the same average value or energy level. The statistics properties of the generated speckle patterns are further investigated by analyzing the standard deviation under different fitting parameters. Precisely tuning the intensity statistics of random speckle patterns could be useful for both fundamental research and practical applications, such as microscopy, imaging, and optical manipulation. 展开更多
关键词 RANDOM SPECKLE pattern INTENSITY statistics local INTENSITY TRANSFORMATION optical MANIPULATION
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Direct Measurement of Non-Classical Photon Statistics with a Multi-Pixel Photon Counter
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作者 Cheng-Jie Ding You-Ying Rong +2 位作者 Yu Chen Xiu-Liang Chen E Wu 《Journal of Electronic Science and Technology》 CAS CSCD 2019年第3期204-212,共9页
Photon number resolving detectors with high accuracy bring broad applications in long-distance laser ranging, ultrafast spectroscopy, and quantum optics. In this paper, we observed the non-classical photon number dist... Photon number resolving detectors with high accuracy bring broad applications in long-distance laser ranging, ultrafast spectroscopy, and quantum optics. In this paper, we observed the non-classical photon number distribution directly with a multi-pixel photon counter (MPPC) instead of a classic Hanbury-Brown and Twiss (HBT) system. The detector’s photon-number resolving ability was characterized by quantum detector tomography. To show the quantum feature of the detector, we further plotted the Wigner function, which was obtained corresponding to the positive operator value measure (POVM) elements. Finally, we declared the observation of non-classical photon statistics from a single color center in nanodiamond by using this detector. 展开更多
关键词 PHOTON COUNTING PHOTON statistics QUANTUM DETECTOR QUANTUM OPTICS
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Incomplete nonextensive statistics and the zeroth law of thermodynamics
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作者 黄志福 欧聪杰 陈金灿 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期144-147,共4页
On the basis of the entropy of incomplete statistics (IS) and the joint probability factorization condition, two controversial problems existing in IS are investigated: one is what expression of the internal energy... On the basis of the entropy of incomplete statistics (IS) and the joint probability factorization condition, two controversial problems existing in IS are investigated: one is what expression of the internal energy is reasonable for a composite system and the other is whether the traditional zeroth law of thermodynamics is suitable for IS. Some new equivalent expressions of the internal energy of a composite system are derived through accurate mathematical calculation. Moreover, a self-consistent calculation is used to expound that the zeroth law of thermodynamics is also suitable for IS, but it cannot be proven theoretically. Finally, it is pointed out that the generalized zeroth law of thermodynamics for incomplete nonextensive statistics is unnecessary and the nonextensive assumptions for the composite internal energy will lead to mathematical contradiction. 展开更多
关键词 classical statistical mechanics THERMODYNAMICS probability theory
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Photon counting statistics in single multi-level quantum system
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作者 王东升 郑雨军 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期307-317,共11页
We theoretically study the statistics of photon emission of single multi-level quantum system by employing the generating functions approach developed recently. The generalized decay constants are included in single m... We theoretically study the statistics of photon emission of single multi-level quantum system by employing the generating functions approach developed recently. The generalized decay constants are included in single multi-level quantum system with quasi-degenerated levels in this work although they are normally neglected in the absence of (quasi-)degeneracies in multi-level quantum system within the rotating wave approximation. The quantum beats, the line shapes and the Mandel's Q parameters, etc. are studied. 展开更多
关键词 photon statistics generating function single quantum system
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Level spacing statistics for two-dimensional massless Dirac billiards
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作者 黄亮 徐洪亚 +1 位作者 来颖诚 Celso Grebogid 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期41-52,共12页
Classical-quantum correspondence has been an intriguing issue ever since quantum theory was proposed. The search- ing for signatures of classically nonintegrable dynamics in quantum systems comprises the interesting f... Classical-quantum correspondence has been an intriguing issue ever since quantum theory was proposed. The search- ing for signatures of classically nonintegrable dynamics in quantum systems comprises the interesting field of quantum chaos. In this short review, we shall go over recent efforts of extending the understanding of quantum chaos to relativistic cases. We shall focus on the level spacing statistics for two-dimensional massless Dirac billiards, i.e., particles confined in a closed region. We shall discuss the works for both the particle described by the massless Dirac equation (or Weyl equation) and the quasiparticle from graphene. Although the equations are the same, the boundary conditions are typically different, rendering distinct level spacing statistics. 展开更多
关键词 quantum chaos level spacing statistics Dirac billiards graphene billiards
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Photon counting statistics of V-type three-level systems:The effects of the field fluctuations
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作者 彭勇刚 郑雨军 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第2期152-157,共6页
We investigate the influence of the field fluctuations to the emission photons of V-type three-level systems.The emission intensity I and Mandel's Q parameter show stochastic resonance with respect to the pure dephas... We investigate the influence of the field fluctuations to the emission photons of V-type three-level systems.The emission intensity I and Mandel's Q parameter show stochastic resonance with respect to the pure dephasing constantγp.The amplitude fluctuation of the field causes these systems to lose their coherence.On the other hand,the amplitude fluctuation provides a new interference method for these systems.The quantum beats are shown in the orthogonal system. 展开更多
关键词 photon counting statistics field fluctuation V-type three-level system
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THE ASYMPTOTIC DISTRIBUTIONS OF EMPIRICAL LIKELIHOOD RATIO STATISTICS IN THE PRESENCE OF MEASUREMENT ERROR
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作者 伍长春 张润楚 《Acta Mathematica Scientia》 SCIE CSCD 2007年第2期232-242,共11页
Suppose that several different imperfect instruments and one perfect instrument are independently used to measure some characteristics of a population. Thus, measurements of two or more sets of samples with varying ac... Suppose that several different imperfect instruments and one perfect instrument are independently used to measure some characteristics of a population. Thus, measurements of two or more sets of samples with varying accuracies are obtained. Statistical inference should be based on the pooled samples. In this article, the authors also assumes that all the imperfect instruments are unbiased. They consider the problem of combining this information to make statistical tests for parameters more relevant. They define the empirical likelihood ratio functions and obtain their asymptotic distributions in the presence of measurement error. 展开更多
关键词 Empirical likelihood ratio statistics asymptotic distribution measurement error
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Topological quantum-phase coherence in full counting statistics of transport electrons with two-body interaction
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作者 郭小芳 薛海斌 梁九卿 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第8期508-515,共8页
The full counting statistics of electron transport through two parallel quantum dots with antiparallel magnetic fluxes is investigated as a probe to detect the topological quantum-phase coherence (TQPC), which resul... The full counting statistics of electron transport through two parallel quantum dots with antiparallel magnetic fluxes is investigated as a probe to detect the topological quantum-phase coherence (TQPC), which results in the characteristic oscillation of the zero-frequency cumulants including the shot noise and skewness. We show explicitly the phase transition of cumulant spectrum-patterns induced by the topology change of electron path-loops while the pattern period, which depends only on the topology (or Chern number), is robust against the variation of Coulomb interaction and interdot coupling strengths. Most importantly we report for the first time on a new type of TQPC, which is generated by the two- particle interaction and does not exist in the single-particle wave function interference. Moreover, the accurately quantized peaks of Fano-factor spectrum, which characterize the super- and sub-Poissonian shot noises, are of fundamental importance in technical applications similar to the superconducting quantum interference device. 展开更多
关键词 topological quantum-phase coherence full counting statistics two-body interaction
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