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AN INFORMATIC APPROACH TO A LONG MEMORY STATIONARY PROCESS

Acta Mathematica Scientia 2023年第6期43卷 2629-2648页

作者：丁义明吴量向绪言 College of Science Wuhan University of Science and TechnologyWuhan 430081China Hubei Province key Laboratory of System Science in Metallurgical Process Wuhan University of Science and TechnologyWuhan 430065China Center of Statistical Research School of StatisticsSouthwestern University of Finance EconomicsChengdu 611130China Hunan Province Cooperative Innovation Center for TCDDLEEZ School of Mathematics and Physics ScienceHunan University of Arts and ScienceChangde 415000China

Long memory is an important phenomenon that arises sometimes in the analysis of time series or spatial *** of the definitions concerning the long memory of a stationary process are based on the second-order properties of the *** mutual information between the past and future I_(p−f) of a stationary process represents the information stored in the history of the process which can be used to predict the *** suggest that a stationary process can be referred to as long memory if its I_(p−f) is *** a stationary process with finite block entropy,I_(p−f) is equal to the excess entropy,which is the summation of redundancies that relate the convergence rate of the conditional(differential)entropy to the entropy *** the definitions of the I_(p−f) and the excess entropy of a stationary process require a very weak moment condition on the distribution of the process,it can be applied to processes whose distributions are without a bounded second moment.A significant property of I_(p−f) is that it is invariant under one-to-one transformation;this enables us to know the I_(p−f) of a stationary process from other *** a stationary Gaussian process,the long memory in the sense of mutual information is more strict than that in the sense of *** demonstrate that the I_(p−f) of fractional Gaussian noise is infinite if and only if the Hurst parameter is H∈(1/2,1).

关键词： mutual information between past and future long memory stationary process excess entropy fractional Gaussian noise

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Effect on multifocal electroretinogram in persistently elevated intraocular pressure by erigeron breviscapus extract

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International Journal of Ophthalmology(English edition) 2011年第4期4卷 349-352页

作者： Xue-Jing Lu, Jun-Guo Duan key Research Institute for Visual Function Protection with TCM Teaching Hospital of Chengdu University of Traditional Chinese Medicine Chengdu 610075 Sichuan Province China key Laboratory for Visual Function and Eye Diseases Chengdu University of Traditional Chinese Medicine Chengdu 610075 Sichuan Province China The No. 452 Military Hospital of China Chengdu 610075 Sichuan Province China

AIM: To observe the effect on multifocal electroretinogram (mfERG) in persistently elevated intraocular pressure (TOP) by erigeron breviscapus extract (also named Dengzhanhua in Chinese) in rat models. METHODS: The rat models with persistently elevated TOP were established by the method of Akira. Then, erigeron breviscapus extract was given for one month to observe the effect on mfERG in persistently elevated TOP in rats. RESULTS: As elevated TOP went on, the mfERG changes were mainly in weaken of reaction density with progressive development. After intervention of erigeron breviscapus extract, the total peak latency of 131 wave had recovered to some extent and the difference was significant when compared with control group (P <0.05); the total response density and P1 wave response density in second circle had risen noticeably, which had significant differences than those of control group (P <0.05). CONCLUSION: Erigeron breviscapus extract can improve the impaired visual function of persistently elevated TOP in rats, suggesting that this extract is the effective part of erigeron breviscapus for optic neuroprotection.

关键词： erigeron breviscapus extract glaucoma multifocal electroretinogram optic neuroprotection

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An improved method for image denoising based on fractional-order integration

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Frontiers of Information Technology & Electronic Engineering 2020年第10期21卷 1485-1493页

作者： Li XU Guo HUANG Qing-li CHEN Hong-yin QIN Tao MEN Yi-fei PU College of Electronics and Materials Engineering Leshan Normal UniversityLeshan 614000China College of Computer Science Sichuan UniversityChengdu 610064China key Lab of Internet Natural Language Processing of sichuan Provincial education department Leshan Normal UniversityLeshan 614000China

Given that the existing image denoising methods damage the texture details of an image,a new method based on fractional integration is ***,the fractional-order integral formula is deduced by generalizing the Cauchy integral,and then the approximate value of the fractional-order integral operator is estimated by a numerical ***,a fractional-order integral mask operator of any order is constructed in eight pixel directions of the *** results show that the proposed image denoising method can protect the edge texture information of the image while removing the ***,this method can obtain higher image feature values and better image vision after denoising than the existing denoising methods,because a texture protection mechanism is adopted during the iterative processing.

关键词： Fractional-order integral Cauchy integral Image denoising Fractional gradient Texture protection

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Structure and luminescence properties of color-tunable phosphor Sr_(2)La_(3)(SiO_(4))_(3)F:Tb^(3+),Sm^(3+)

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稀土学报:英文版 2023年第9期41卷 1288-1294,I0001页

作者： Haikun Liu Kun Nie Yuanyuan Zhang Lefu Mei Dina V.Deyneko Xiaoxue Ma department of Energy and Chemical Engineering Dongguan University of TechnologyDongguan 523808China State key Laboratory of New Textile Materials&Advanced Processing Technology and Hubei key Laboratory for New Textile Materials and Applications School of Materials Science and EngineeringKey Laboratory of Polyphenylene Sulfide Fiber and Application in Textile IndustryWuhan Textile UniversityWuhan430200China Beijing key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes National Laboratory of Mineral MaterialsSchool of Materials Sciences and TechnologyChina University of GeosciencesBeijing 100083China School of Materials Sciences and Technology Dongguan University of TechnologyDongguan 523808China School of Materials Science and Engineering Xi'an Jiaotong UniversityXi'an 710049China department of Chemistry Lomonosov Moscow State UniversityMoscow 119991Russia Laboratory of Arctic Mineralogy and Material Sciences Kola Science CentreRussian Academy of Sciences14 Fersman Str.184209ApatityRussia

A series of single-phase and color-tunable phosphors Sr_(2)La_(3)(SiO_(4))_(3)F:0.15Tb^(3+),xSm^(3+)(SLSOF:0.15Tb^(3+),xSm^(3+)) was prepared using solid-state *** X-ray diffraction(XRD) was used to characterize the phase of the as-prepared *** synthesized phosphors have apatite-type structure without other ***^(3+) and Tb^(3+) ions substitute La^(3+) into the lattice and form a single-phase solid *** elements are evenly distributed in the sample according to the scanning electron microscopy(SEM) *** crystal structure of the host phosphor was refined by the Rietveld *** optical properties were studied in detail by investigation of the luminescence and diffuse spectra,fluorescence decay curves and energy transfer *** phosphor color can be changed from green(0.29,0.48) to yellow/orange and red(0.57,0.42) via adjusting the doping ratio of Sm^(3+).The SLSOF:0.15Tb^(3+),xSm^(3+)phosphors can emit typical multicolor light such as green,yellow,orange and red with gradually increasing Sm^(3+)doping *** results indicate the occurrence of the energy transfer which results in the color-tunable properties of the phosphors.

关键词： Apatite Calcination Phosphor Optical property Luminescence Rare earths

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Phosphate film free of chromate, fluoride and nitrite on AZ31 magnesium alloy and its corrosion resistance

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Transactions of Nonferrous Metals Society of China 2012年第11期22卷 2713-2718页

作者：崔学军刘春海杨瑞嵩李明田林修洲龚敏四川理工学院材料腐蚀与防护四川省重点实验室自贡643000 四川理工学院材料与化学工程学院自贡643000

A phosphate solution free of chromate, fluoride and nitrite was prepared and an environment-friendly film was obtained on AZ31 magnesium alloy surface via the chemical deposition method. The morphology, composition, phase structure and its corrosion resistance were studied. The effects of film-forming temperature and free acid on corrosion resistance, microstructure and electrochemical behavior of the film were discussed. The results indicate that the corrosion resistance of AZ31 with the phosphate film was better than blank AZ31 substrate, which was most attributed to the great inhibitive action on the anodic dissolution and cathodic hydrogen evolution of the film.

关键词： magnesium alloy AZ31 alloy phosphate conversion coating chromate-free film corrosion resistance anodicdissolution cathodic hydrogen evolution

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Recent advances in plant immunity with cell death:A review

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Journal of Integrative Agriculture 2022年第3期21卷 610-620页

作者： YIN Jun-jie XIONG Jun XU Li-ting CHEN Xue-wei LI Wei-tao State key Laboratory of Crop Gene Exploration and Utilization in Southwest China Rice Research InstituteSichuan Agricultural University at WenjiangChengdu 611130P.R.China

Cell death is an important physiological phenomenon in *** can be programmed or *** cell death is usually induced by abiotic or biotic *** studies have shown that many proteins regulate both cell death and immunity in ***,we provide a review on the advances in plant immunity with cell death,especially the molecular regulation and underlying mechanisms of those proteins involved in both cell death and plant *** addition,we discuss potential approaches toward improving plant immunity without compromising plant growth.

关键词： cell death unprogrammed cell death programmed cell death hypersensitive response reactive oxygen species plant immunity resistance

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Efficient Feature Extraction Using Apache Spark for Network Behavior Anomaly Detection

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Tsinghua Science and Technology 2018年第5期23卷 561-573页

作者： Xiaoming Ye Xingshu Chen Dunhu Liu Wenxian Wang Li Yang Gang Liang Guolin Shao School of Cybersecurity Chengdu University of Information Technology Chengdu 610225 and the College of Computer Science Sichuan University Chengdu 610065 China College of Cybersecurity Sichuan University Chengdu 610065 China School of Management Chengdu University of Information Technology Chengdu 610103 China College of Compute Science Sichuan University Chengdu 610065 China

Extracting and analyzing network traffic feature is fundamental in the design and implementation of network behavior anomaly detection methods. The traditional network traffic feature method focuses on the statistical features of traffic volume. However, this approach is not sufficient to reflect the communication pattern features. A different approach is required to detect anomalous behaviors that do not exhibit traffic volume changes, such as low-intensity anomalous behaviors caused by Denial of Service/Distributed Denial of Service （DoS/DDoS） attacks, Internet worms and scanning, and BotNets. We propose an efficient traffic feature extraction architecture based on our proposed approach, which combines the benefit of traffic volume features and network communication pattern features. This method can detect low-intensity anomalous network behaviors and conventional traffic volume anomalies. We implemented our approach on Spark Streaming and validated our feature set using labelled real-world dataset collected from the sichuan University campus network. Our results demonstrate that the traffic feature extraction approach is efficient in detecting both traffic variations and communication structure changes. Based on our evaluation of the MIT-DRAPA dataset, the same detection approach utilizes traffic volume features with detection precision of 82.3% and communication pattern features with detection precision of 89.9%. Our proposed feature set improves precision by 94%.

关键词： feature extraction graph theory network behavior anomaly detection Apache Spark

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The Influence of Extractable Organic Matter on Pore Development in the Late Triassic Chang 7 Lacustrine Shales, Yanchang Formation, Ordos Basin, China

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1508-1522页

作者： HAN Hui LIU Pengwei DING Zhengang SHI Pitong JIA Jianchao ZHANG Wei LIU Yan CHEN Shijia LU Jungang Chen Kang PENG Xudong WANG Zhiyong XIAO Shuqi GAO Yuans State key Laboratory of Oil and Gas Reservoir Geology and Exploration Southwest Petroleum University Chengdu 610500 Shandong Provincial key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and Technology Qingdao 266590 State key Laboratory of Petroleum Resources & Prospecting China University of Petroleum Beijing 102249 Research Institute of Shaanxi Yanchang Petroleum (Group) Co. Ltd. Xi 'ani 710000 Development Business Unit of Huabei Oilfield Company Petro China Renqiu Hebei 062552 Research Institute of Petroleum Exploration and Development of Huabei Oilfield Company Petro China Renqiu Hebei 062552 Institute of Mud Logging Technology and Engineering Yangtze University Jingzhou Hubei 434023 Beijing Center for Physical and Chemical Analysis Beijing 100089

To investigate the influence of extractable organic matter （EOM） on pore evolution of lacustrine shales, Soxhlet extraction, using dichloromethane, was performed on a series of Chang 7 shale samples （Ordos Basin, China） with vitrinite reflectance of 0.64% to 1.34%. Low-pressure gas adsorption experiments were conducted on the samples before and after extraction. The pore structure parameters were calculated from the gas adsorption data. The results show complex changes to the pore volumes and surface areas after extraction. The pore development of both the initial and extracted samples is strongly controlled by total organic carbon （TOC） content. Micropores developed mainly in organic matter （OM）, while mesopores and macropores predominantly developed in fractions other than OM. The influence of EOM on micropores is stronger than on mesopores and macropores. Organic solvents with a higher boiling point should be used to explore the effect of EOM on pore structure in the future.

关键词： lacustrine shale pore development extraction shale gas Chang 7 Ordos Basin

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Weak cosmic censorship conjecture in the nonlinear electrodynamics black hole under the charged scalar field

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Communications in Theoretical Physics 2020年第1期72卷 89-95页

作者： Tianhao Bai Wei Hong Benrong Mu Jun Tao Center for Theoretical Physics College of PhysicsSichuan UniversityChengdu610065China Physics Teaching and Research Section College of Medical TechnologyChengdu University of Traditional Chinese MedicineChengdu 611137China

In this paper,we study the thermodynamics and the weak cosmic censorship conjecture of the nonlinear electrodynamics black hole under the scattering of a charged complex scalar *** to the energy and charge fluxes of the scalar field,the variations of this black hole’s energy and charge can be calculated during an infinitesimal time *** scalar field scattering,the variation of the black hole is calculated in the extended and normal phase *** the normal phase space,the cosmological constant and the normalization parameter are fixed,and the first and second laws of thermodynamics can also be *** the extended phase space,the cosmological constant and the normalization parameter are considered as thermodynamic variables,and the first law of thermodynamics is valid,but the second law of thermodynamics is not ***,the weak cosmic censorship conjecture is both valid in the extended and normal phase spaces.

关键词： nonlinear electrodynamics black hole weak cosmic censorship conjecture complex scalar field thermodynamics

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A new Doppler frequency anomaly algorithm for surface current measurement with SAR

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Journal of Oceanology and Limnology 2022年第2期40卷 470-484页

作者： Lihua WANG Yanghua GAO Peng LU Li FAN Yunxuan ZHOU department of Geography and Spatial Information Techniques Center for Land and Marine Spatial Utilization and Governance ResearchNingbo UniversityNingbo 315211China Institute of East China Sea Ningbo UniversityNingbo 315211China Chongqing Institute of Meteorological Sciences Chongqing 401147China College of Geo-Exploration Science and Technology Jilin UniversityChangchun 130026China State key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200062China

Values for Doppler center frequency are calculated from the echo signal at the satellite using the Doppler centroid method and so include the predicted Doppler frequency caused by the relative motion of the satellite and the Earth,which is the main component of Doppler center frequency and must be removed to obtain the Doppler frequency anomaly for ocean current *** this paper,a new Doppler frequency anomaly algorithm was proposed when measuring surface currents with synthetic aperture radar(SAR).The key of the proposed algorithm involved mean filtering method in the range direction and linear fitting in the azimuth direction to remove the radial and the azimuthal component of predicted Doppler frequency from the Doppler center frequency,*** basis is that the theoretical Doppler center frequency model of SAR exhibits an approximately linear characteristic in both the range direction and in the azimuth *** the help of the new algorithm for predicted Doppler frequency removal,the estimation error of Doppler frequency anomaly can be reduced by avoiding employing the theoretical antenna pattern and imperfect satellite attitude parameters in the conventional Doppler frequency *** measurement results demonstrated that,compared to the conventional Doppler frequency with/without error correction method,the proposed algorithm allows for a pronounced improvement in the current measuring accuracy in comparison with the global ocean multi-observation(MOB)*** addition,the eff ectiveness and robustness of the proposed Doppler algorithm has been demonstrated by its application in the high velocity current in the Kuroshio region.

关键词： synthetic aperture radar(SAR) Doppler frequency Doppler frequency anomaly current retrieval ocean surface currents

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