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电影《阿甘正传》的人物语言分析 被引量:2
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作者 杨鹏 《西安文理学院学报(社会科学版)》 2016年第5期24-26,共3页
电影艺术价值传递过程中,语言是重要的手段,语言能够刻画人物性格、推进故事情节,尤其是《阿甘正传》的人物语言具有代表性,因智力因素和成长环境导致阿甘的非隐喻性的语言观,影片恰恰通过这种非隐喻的语言来描述了当时的社会现实,向人... 电影艺术价值传递过程中,语言是重要的手段,语言能够刻画人物性格、推进故事情节,尤其是《阿甘正传》的人物语言具有代表性,因智力因素和成长环境导致阿甘的非隐喻性的语言观,影片恰恰通过这种非隐喻的语言来描述了当时的社会现实,向人们传递了人性的美好,展现了对生活充满希望的审美境界。 展开更多
关键词 《阿甘正传》 人物话语 时征分析
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Feature extraction and damage alarming using time series analysis 被引量:4
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作者 刘毅 李爱群 +1 位作者 费庆国 丁幼亮 《Journal of Southeast University(English Edition)》 EI CAS 2007年第1期86-91,共6页
Aiming at the problem of on-line damage diagnosis in structural health monitoring (SHM), an algorithm of feature extraction and damage alarming based on auto-regressive moving-average (ARMA) time series analysis i... Aiming at the problem of on-line damage diagnosis in structural health monitoring (SHM), an algorithm of feature extraction and damage alarming based on auto-regressive moving-average (ARMA) time series analysis is presented. The monitoring data were first modeled as ARMA models, while a principalcomponent matrix derived from the AR coefficients of these models was utilized to establish the Mahalanobisdistance criterion functions. Then, a new damage-sensitive feature index DDSF is proposed. A hypothesis test involving the t-test method is further applied to obtain a decision of damage alarming as the mean value of DDSF had significantly changed after damage. The numerical results of a three-span-girder model shows that the defined index is sensitive to subtle structural damage, and the proposed algorithm can be applied to the on-line damage alarming in SHM. 展开更多
关键词 feature extraction damage alarming time series analysis structural health monitoring
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Space-Time Characteristic Analysis of Wind Field over the South Indian Ocean 被引量:2
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作者 佟凯 刘金芳 +2 位作者 闫明 李颜 杨亮 《Marine Science Bulletin》 CAS 2003年第2期5-13,共9页
According to the ship observation data over the South Indian Ocean during 1950 1995, taking 1°× 1° and 5°× 5°grid, the characteristics and variation rule of wind are analyzed. Through ana... According to the ship observation data over the South Indian Ocean during 1950 1995, taking 1°× 1° and 5°× 5°grid, the characteristics and variation rule of wind are analyzed. Through analyzing the chart of isopleths of the monthly elements, the conclusion that the seasonal variation of the wind field over the South Indian Ocean is less remarkable than that in the oceans of the Northern Hemisphere is got. The seasonal variation of the wind field is also obvious in this region, but the seasonal difference is little. The wind in winter is stronger than in summer, correspondingly, the average wind speed is higher, and the frequencies of gale of forces ≥ 6 and 8 are also higher. The north of 10°S is a monsoon area; Southeast wind prevails all over the year in the rest of the trade wind area; Westerly wind dominates in the south of 40°S. This paper provides specific data of wind field and variation for ship ocean transportation, ocean-going visits and scientific experiment. 展开更多
关键词 South Indian Ocean Pressure field Wind field
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The motion analysis of fire video images based on moment features and flicker frequency 被引量:9
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作者 LIJin FONG +3 位作者 N.K.,CHOW W.K.,WONG L.T.,LUPuyi XUDian-guo 《Journal of Marine Science and Application》 2004年第1期81-86,共6页
In this paper, motion analysis methods based on the moment features and flicker frequency features for early fire flame from ordinary CCD video camera were proposed, and in order to describe the changing of flame and ... In this paper, motion analysis methods based on the moment features and flicker frequency features for early fire flame from ordinary CCD video camera were proposed, and in order to describe the changing of flame and disturbance of non-flame phenomena further more, the average changing pixel number of the first-order moments of consecutive flames has been defined in the moment analysis as well. The first-order moments of all kinds of flames used in our experiments present irregularly flickering, and their average changing pixel numbers of first-order moments are greater than fire-like disturbances. For the analysis of flicker frequency of flame, which is extracted and calculated in spatial domain, and therefore it is computational simple and fast. The method of extracting flicker frequency from video images is not affected by the catalogues of combustion material and distance. In experiments, we adopted two kinds of flames, i. e. , fixed flame and movable flame. Many comparing and disturbing experiments were done and verified that the methods can be used as criteria for early fire detection. 展开更多
关键词 fire video images moment features flicker frequency
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SPATIAL DISTRIBUTION AND VARIATION TENDENCY OF DROUGHTS AND FLOODS IN HUNAN PROVINCE DURING THE PAST 36 YEARS 被引量:2
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作者 张剑明 章新平 +4 位作者 黎祖贤 张健 肖艳 刘燚 周伟 《Journal of Tropical Meteorology》 SCIE 2011年第4期385-391,共7页
Using the 1970-2005 annual precipitation and evaporation data at 80 gauge stations across Hunan province,this work analyzes the spatial distribution and variation tendency of the local droughts and floods using linear... Using the 1970-2005 annual precipitation and evaporation data at 80 gauge stations across Hunan province,this work analyzes the spatial distribution and variation tendency of the local droughts and floods using linear regression,wavelet analysis,abrupt change,clusters,Empirical Orthogonal Function (EOF) and rotated EOF (REOF).Results show that there are four dry areas and three wet areas in Hunan.The whole province exhibits a moistening trend except some small areas in western,eastern and southern Hunan.The most prominent feature of annual precipitation is that the whole province basically displays a consistent variation tendency,as far as the dominant EOF mode is concerned.In addition,the spatial features of the other EOF modes include dry-wet differences,e.g.wet (or dry) in the north versus dry (or wet) in the south,wet (or dry) in the center and dry (or wet) in the surrounding areas.The distribution of the ratios of evaporation to precipitation exhibits both common features as well as spatial differences,which can be classified into four types:South Hunan,North Hunan,Northeast Hunan,and Central Hunan.There is an abrupt change from dry to wet patterns in the early 1990s.Generally,the drought-flood distribution presents variations of three periods.In the late 2000s,Hunan province will be in a period of drought,followed by a period of flood. 展开更多
关键词 spatiotemporal characteristics REOF Morlet analysis Hunan province drought and flood
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Machine learning based online fault prognostics for nonstationary industrial process via degradation feature extraction and temporal smoothness analysis 被引量:2
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作者 HU Yun-yun ZHAO Chun-hui KE Zhi-wu 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第12期3838-3855,共18页
Fault degradation prognostic, which estimates the time before a failure occurs and process breakdowns, has been recognized as a key component in maintenance strategies nowadays. Fault degradation processes are, in gen... Fault degradation prognostic, which estimates the time before a failure occurs and process breakdowns, has been recognized as a key component in maintenance strategies nowadays. Fault degradation processes are, in general,slowly varying and can be modeled by autoregressive models. However, industrial processes always show typical nonstationary nature, which may bring two challenges: how to capture fault degradation information and how to model nonstationary processes. To address the critical issues, a novel fault degradation modeling and online fault prognostic strategy is developed in this paper. First, a fault degradation-oriented slow feature analysis(FDSFA) algorithm is proposed to extract fault degradation directions along which candidate fault degradation features are extracted. The trend ability assessment is then applied to select major fault degradation features. Second, a key fault degradation factor(KFDF) is calculated to characterize the fault degradation tendency by combining major fault degradation features and their stability weighting factors. After that, a time-varying regression model with temporal smoothness regularization is established considering nonstationary characteristics. On the basis of updating strategy, an online fault prognostic model is further developed by analyzing and modeling the prediction errors. The performance of the proposed method is illustrated with a real industrial process. 展开更多
关键词 fault prognostic NONSTATIONARY industrial process fault degradation-oriented slow feature analysis(FDSFA) temporal smoothness regularization
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Metastasis to the gallbladder:A single-center experience of 20 cases in South Korea 被引量:5
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作者 Won Jae Yoon Yong Bum Yoon +2 位作者 Youn Joo Kim Ji Kon Ryu Yong-Tae Kim 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第38期4806-4809,共4页
AIM: To evaluate the clinicopathologic characteristics of patients with metastases to the gallbladder (MGBs). METHODS: We performed a single-center retrospective study of 20 patients with MGBs diagnosed pathologic... AIM: To evaluate the clinicopathologic characteristics of patients with metastases to the gallbladder (MGBs). METHODS: We performed a single-center retrospective study of 20 patients with MGBs diagnosed pathologically from 1999 to 2007. RESULTS: Among 417 gallbladder (GB) malignancies, 20 (4.8%) were MGBs. The primary malignancies originated from the stomach (n = 8), colorectum (n = 3), liver (n = 2), kidney (n = 2), skin (n = 2), extrahepatic bile duct (n = 1), uterine cervix (n = 1), and appendix (n = 1). Twelve patients were diagnosed metachronously, presenting with cholecystitis (n = 4), abdominal pain (n = 2), jaundice (n = 1), weight loss (n = 1), and serum CA 19-9 elevation (n = 1); five patients were asymptomatic. The median survival after the diagnosis of MGB was 8.7 mo. On Cox regression analysis, R0 resection was the only factor associated with a prolonged survival [hazard ratio (HR): 0.01, P = 0.002]; presentation with cholecystitis was associated with poor survival (HR: 463.27, P = 0.006). CONCLUSION: MGBs accounted for 4.8% of all pathologically diagnosed GB malignancies. The most common origin was the stomach. The median survival of MGI3 was 8.7 mo. 展开更多
关键词 GALLBLADDER NEOPLASMS Gastrointestinalneoplasms Neoplasm metastasis Biliary tract neoplasms
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Gustiness and coherent structure under weak wind period in atmospheric boundary layer 被引量:2
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作者 Li Qi-Long Cheng Xue-Ling Zeng Qing-Cun 《Atmospheric and Oceanic Science Letters》 CSCD 2016年第1期52-59,共8页
Statistical analysis of turbulent and gusty characteristics in the atmospheric boundary layer under weak wind period has been carried out.The data used in the analysis were from the multilevel ultrasonic anemometer-th... Statistical analysis of turbulent and gusty characteristics in the atmospheric boundary layer under weak wind period has been carried out.The data used in the analysis were from the multilevel ultrasonic anemometer-thermometers at 47 m,120 m,and 280 m levels on Beijing 325 m meteorological tower.The time series of 3D atmospheric velocity were analyzed by using conventional Fourier spectral analysis and decompose into three parts:basic mean flow(period > 10 min),gusty disturbances(1 min < period < 10 min)and turbulence fluctuations(period < 1 min).The results show that under weak mean wind condition:1)the gusty disturbances are the most strong fluctuations,contribute about 60% kinetic energy of eddy kinetic energy and 80% downward flux of momentum,although both the eddy kinetic energy and momentum transport are small in comparison with those in strong mean wind condition;2)the gusty wind disturbances are anisotropic;3)the gusty wind disturbances have obviously coherent structure,and their horizontal and vertical component are negatively correlated and make downward transport of momentum more effectively;4)the friction velocities related to turbulence and gusty wind are approximately constant with height in the surface layer. 展开更多
关键词 Atmospheric boundary layer gusty wind coherent structure weak wind downward flux of momentum
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Introducing driving-force information increases the predictability of the North Atlantic Oscillation
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作者 PAN Xinnong WANG Geli YANG Peicai 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第5期329-336,共8页
The North Atlantic Oscillation(NAO)is the most prominent mode of atmospheric variability in the Northern Hemisphere.Because of the close relationship between the NAO and regional climate in Eurasia,North Atlantic,and ... The North Atlantic Oscillation(NAO)is the most prominent mode of atmospheric variability in the Northern Hemisphere.Because of the close relationship between the NAO and regional climate in Eurasia,North Atlantic,and North America,improving the prediction skill for the NAO has attracted much attention.Previous studies that focused on the predictability of the NAO were often based upon simulations by climate models.In this study,the authors took advantage of Slow Feature Analysis to extract information on the driving forces from daily NAO index and introduced it into phase-space reconstruction.By computing the largest Lyapunov exponent,the authors found that the predictability of daily NAO index shows a significant increase when its driving force signal is considered.Furthermore,the authors conducted a short-term prediction for the NAO by using a global prediction model for chaotic time series that incorporated the driving-force information.Results showed that the prediction skill for the NAO can be largely increased.In addition,results from wavelet analysis suggested that the driving-force signal of the NAO is associated with three basic drivers:the annual cycle(1.02 yr),the quasi-biennial oscillation(QBO)(2.44 yr);and the solar cycle(11.6 yr),which indicates the critical roles of the QBO and solar activities in the predictability of the NAO. 展开更多
关键词 North Atlantic Oscillation slow feature analysis driving force characteristics time series prediction
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Sandwich-Boomerang attack on reduced round CLEFIA
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作者 毛明 Qin Zhiguang 《High Technology Letters》 EI CAS 2014年第1期48-53,共6页
CLEFIA(named after the French word "Clef" meaning "Key") is an efficient,highly secure block cipher proposed by SONY Corporation in the 14 th International Workshop on Fast Software Encryption(FSE-... CLEFIA(named after the French word "Clef" meaning "Key") is an efficient,highly secure block cipher proposed by SONY Corporation in the 14 th International Workshop on Fast Software Encryption(FSE-2007) and many cryptanalyses have been used to analyze it.According to the property of CLEFIA,a new technique Sandwich-Boomerang cryptanalysis is used on it.An 8-round Sandwich-Boomerang distinguisher of CLEFIA is constructed using the best differential characteristic of CLEFIA.And then,based on the distinguisher,an attack against 10-round CLEFIA is proposed.The number of chosen plaintexts required is 2^(119)(or 2^(120)) and the time complexity is 2^(120)(or 2^(121)).Compared with a 7-round impossible Boomerang distinguisher presented by Choy in the 4th International Workshop on Security(IWSEC-2009),the differential characteristics used in the attack are all the best ones,so it is believed that the attack is the best result that the Boomerang attacks can get on CLEFIA at present. 展开更多
关键词 block cipher CLEFIA Sandwich-Boomerang distinguisher
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Spatial and Temporal Variations of Daily Ranges of the Geomagnetic Vertical Component in the Chinese Mainland
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作者 Li Junhui Li Qi +3 位作者 Wang Xingzhou He Kang Tao Yuechao Chen Jun 《Earthquake Research in China》 2013年第1期91-100,共10页
In this paper, we use the daily ranges of the vertical magnetic intensity of approximately 76 geomagnetic stations from January 1, 2008 to December 31, 2010 to analyze the spatial and temporal characteristics of Z ran... In this paper, we use the daily ranges of the vertical magnetic intensity of approximately 76 geomagnetic stations from January 1, 2008 to December 31, 2010 to analyze the spatial and temporal characteristics of Z ranges. The results are summarized as follows: (1) Temporally, we use regressive analysis and FFT analysis to analyze the data. The results show that the Z component daily ranges of all stations have an obvious cyclical variation, the computed Fourier spectra of all data sets have clearly resolved the required periodicities in the data, in the form of distinct peaks at days 365, 183, 22, and 73, and the power spectra of day 365 is the highest in all periods. (2) In terms of spatial variation, the daily ranges show nonlinear variation with latitude in China. The results show the existence of a point of inflexion (maximal value point) nearby at about 25°N, the daily ranges of Z rise from 15°~25°N and have a good linear decrease variation along with 25°~50°N. (3) Compared with the spatial and temporal variations of Z daily ranges with the Sq current inversion, we found that the spatial and temporal characteristics of Z ranges are decided mainly by the spatio-temporal evolution of the Sq current system. (4) If the latitudes of the maximum amplitudes of variation of the vertical component in the geomagnetic quiet days are roughly taken as the latitudes corresponding to the foci of Sq overhead current system, we can see that these latitudes of foci become higher in summer, are lowest in winter and highest during Equinoxes, displaying conspicuous monthly and daily variations. For two successive geomagnetic quiet days, the latitudes of foci may vary ten degrees. 展开更多
关键词 Chinese mainland GEOMAGNETIC Daily ranges of Z component Spatial and temporal variations
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Characterization and expression of sweetfish (Plecoglossus altivelis) cathepsin D 被引量:2
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作者 Yu JIAO Chang-Hong LI +1 位作者 Xin-Jiang LU Jiong CHEN 《Zoological Research》 CAS CSCD 北大核心 2014年第4期294-299,共6页
Cathepsin D (CTSD) is a lysosomal acidic endoproteinase that plays an important role in immune response, In this study, we obtained sweetfish (Plecoglossus altivelis) CTSD (PaCTSD) via de-novo transcriptome sequ... Cathepsin D (CTSD) is a lysosomal acidic endoproteinase that plays an important role in immune response, In this study, we obtained sweetfish (Plecoglossus altivelis) CTSD (PaCTSD) via de-novo transcriptome sequencing of sweetfish macrophages. The full length cDNA sequence of PaCTSD was 1955 bp encoding a propeptide of 397 amino acids. The deduced protein had a calculated molecular weight of 43.17x 103. Multiple alignment with other known CTSD amino acid sequences revealed amino acid conservation through the teleosts. Phylogenetic tree analysis showed that PaCTSD grouped tightly with other fish CTSD, and was close to that of Atlantic salmon and rainbow trout. Subsequently, PaCTSD was prokaryotically expressed and refolded by the urea gradient method on a nickel-nitrilotriacetic acid column. Enzyme activity analysis showed that PaCTSD exhibited pH-dependent proteolytic activity. Quantitative real-time PCR showed that PaCTSD mRNA was expressed in all detected tissues in healthy sweetfish. The highest expression was observed in the spleen and white blood cells, followed by liver, head-kidney, kidney, intestine, gill, and muscle. After Listonella anguillarum infection, PaCTSD transcripts were up-regulated significantly in liver, spleen, white blood cells, and head-kidney of sweetfish. In summary, PaCTSD has proteolytic activity and is closely involved in the immune response of sweetfish. 展开更多
关键词 Cathepsin D Plecolossus altivelis Bacterial infection Prokaryotic expression QRT-PCR
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The modulation recognition based on decision-making mechanism and neural network integrated classifier
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作者 袁海英 Sun Xun Li Haitao 《High Technology Letters》 EI CAS 2013年第2期132-136,共5页
A neural network integrated classifier(NNIC) designed with a new modulation recognition algorithm based on the decision-making tree is proposed in this paper.Firstly,instantaneous parameters are extracted in the time ... A neural network integrated classifier(NNIC) designed with a new modulation recognition algorithm based on the decision-making tree is proposed in this paper.Firstly,instantaneous parameters are extracted in the time domain by the coordinated rotation digital computer(CORDIC) algorithm based on the extended convergence domain and feature parameters of frequency spectrum and power spectrum are extracted by the time-frequency analysis method.All pattern identification parameters are calculated under the I/Q orthogonal two-channel structure,and constructed into the feature vector set.Next,the classifier is designed according to the modulation pattern and recognition performance of the feature parameter set,the optimum threshold is selected for each feature parameter based on the decision-making mechanism in a single classifier,multi-source information fusion and modulation recognition are realized based on feature parameter judge process in the NNIC.Simulation results show NNIC is competent for all modulation recognitions,8 kinds of digital modulated signals are effectively identified,which shows the recognition rate and anti-interference capability at low SNR are improved greatly,the overall recognition rate can reach 100%when SNR is12dB. 展开更多
关键词 modulation recognition decision-making mechanism neural network integratedclassifier (NNIC) feature extraction
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Analysis of Abnormal Characteristics of Regional Crustal Deformation before the Menyuan MS6.4 Earthquake by GPS Continuous Data 被引量:2
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作者 Ma Haiping Feng Jiangang +1 位作者 Guo Peng Shi Xuelu 《Earthquake Research in China》 CSCD 2017年第2期234-238,共5页
In order to study the characteristics of crustal deformation around the epicenter before the 2016 M_S6. 4 Menyuan earthquake,the GPS continuous stations of the period from 2010 to 2016 were selected according to the o... In order to study the characteristics of crustal deformation around the epicenter before the 2016 M_S6. 4 Menyuan earthquake,the GPS continuous stations of the period from 2010 to 2016 were selected according to the observation data of the tectonic environment monitoring network in Chinese Mainland. The deformation characteristics of the crust before the earthquake were discussed through inter-station baseline time series analysis and the strain time series analysis in the epicentral region. The results show that a trend turn of the baseline movement state around the epicenter region occurred after 2014,and the movement after 2014 reflects an obvious decreasing trend of compressional deformation.During this period,the stress field energy was in a certain accumulation state. Since the beginning of 2014,the EW-component linear strain and surface strain rate weakened gradually before the earthquake. It shows that there was an obvious deformation deficit at the epicentral area in the past two years,which indicates that the region accumulated a high degree of strain energy before the earthquake. Therefore,there was a significant background change in the area before the earthquake. The results of the study can provide basic research data for understanding the seismogenic process and mechanism of this earthquake. 展开更多
关键词 Menyuan Ms6. 4 earthquake GPS reference station Baseline time series Strain time series
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The Research of Fractal Characteristics of the Electrocardiogram in a Real Time Mode
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作者 Valery Antonov Anatoly Kovalenko +1 位作者 Artem Zagaynov Vu Van Quang 《Journal of Mathematics and System Science》 2012年第3期191-195,共5页
The article presents the results of recent investigations into Holter monitoring of ECG, using non-linear analysis methods. This paper discusses one of the modern methods of time series analysis--a method of determini... The article presents the results of recent investigations into Holter monitoring of ECG, using non-linear analysis methods. This paper discusses one of the modern methods of time series analysis--a method of deterministic chaos theory. It involves the transition from study of the characteristics of the signal to the investigation of metric (and probabilistic) properties of the reconstructed attractor of the signal. It is shown that one of the most precise characteristics of the functional state of biological systems is the dynamical trend of correlation dimension and entropy of the reconstructed attractor. On the basis of this it is suggested that a complex programming apparatus be created for calculating these characteristics on line. A similar programming product is being created now with the support of RFBR. The first results of the working program, its adjustment, and further development, are also considered in the article. 展开更多
关键词 Holter monitoring ECG correlation dimension fractal analysis of time series non-linear dynamics of heart rate
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Using acoustic technique to detect leakage in city gas pipelines 被引量:2
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作者 陈志刚 连香姣 赫亮 《Journal of Central South University》 SCIE EI CAS 2012年第8期2373-2379,共7页
For solving the difficult problem of leakage detection in city gas pipelines, a method using acoustic technique based on instantaneous energy (IE) distribution and correlation analysis was proposed. Firstly, the basic... For solving the difficult problem of leakage detection in city gas pipelines, a method using acoustic technique based on instantaneous energy (IE) distribution and correlation analysis was proposed. Firstly, the basic theory of leakage detection and location was introduced. Then the physical relationship between instantaneous energy and structural state variation of a system was analyzed theoretically. With HILBERT-HUANG transformation (HHT), the instantaneous energy distribution feature of an unstable acoustic signal was obtained. According to the relative contribution method of the instantaneous energy, the noise in signal was eliminated effectively. Furthermore, in order to judge the leakage, the typical characteristic of the instantaneous energy of signal in the input and output end was discussed using correlative analysis. A number of experiments were carried out to classify the leakage from normal operations, and the results show that the leakages are successfully detected and the average recognition rate reaches 93.3% among three group samples. It is shown that the method using acoustic technique with IED and correlative analysis is effective and it may be referred in other pipelines. 展开更多
关键词 city gas pipeline leakage detection acoustic technique instantaneous energy distribution correlative analysis
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Self-Similar Characteristic for the Ramp Structures of Wind Speed
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作者 SONG Zong-Peng HU Fei +1 位作者 XU Jing-Jing CHENG Xue-Ling 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第4期320-323,共4页
Time series of wind speed are composed of large and small ramp structures. Data analysis reveals a power law relation between the linear slope of ramp structures and the time scale. This suggests that these ramp struc... Time series of wind speed are composed of large and small ramp structures. Data analysis reveals a power law relation between the linear slope of ramp structures and the time scale. This suggests that these ramp structures of wind speed have a self-similar characteristic. The lower limit of the self-similar scale range was 2 s. The upper limit is unexpectedly large at 27 rain. Data are collected from grassland, city, and lake areas. Although these data have different underlying surfaces, all of them clearly show a power law relation, with slight differences in their power exponents. 展开更多
关键词 ramp structure SELF-SIMILARITY power law time series of wind speed
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A Statistical Analysis on Recent Tidal Triggering of the Earthquake in the Tianshan Seismic Zone
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作者 Li Jin Jiang Haikun +2 位作者 Qu Junhao Huang Yu Gao Chaojun 《Earthquake Research in China》 CSCD 2015年第2期203-213,共11页
A statistical analysis is done to study the spatio-temporai features of earthquake activity in the Tianshan seismic belt triggered by tide, based on Schuster's test. The data we choose is the ML ≥2. 0 earthquakes fr... A statistical analysis is done to study the spatio-temporai features of earthquake activity in the Tianshan seismic belt triggered by tide, based on Schuster's test. The data we choose is the ML ≥2. 0 earthquakes from January 1, 2010 to August 31, 2012 in eastern Tianshan, and the calculation is on tidal body stress. The results show that the p-value based on the time window smoothing of Schuster's test corresponds better with the strong earthquakes in the Tianshan seismic belt, especially for a long time before the November 1, 2011 Nilka Ms6. 0 earthquake, when the p-value of the Schuster's test was always lower than the threshold of 0. 05 for tidal trigger of earthquake, but after the Niika Ms6. 0 earthquake, that value was quickly restored to a high level, which reflects a close relationship between the Nilka Ms6. 0 earthquake and the Earth tide. According to the p-value based on the spatial window smoothing of Schuster's test, the Nilka Ms6. 0 earthquake was at or near the tidal triggering area. Thus we can see from the spatio-temporal results that the Nilka Ms6. 0 earthquake was obviously triggered by Earth fide. 展开更多
关键词 Tianshan seismic zone Nilka earthquake Tidal triggering Schuster's test
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Face Recognition Using LDA with Wavelet Transform Approach
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作者 Neeta Nain Akshay Kumar +3 位作者 Amlesh Kumar Mohapatra Ashok Kumar Ratan Das Nemi Chand Singh 《Computer Technology and Application》 2011年第5期401-405,共5页
Linear Discriminant Analysis (LDA) is one of the principal techniques used in face recognition systems. LDA is well-known scheme for feature extraction and dimension reduction. It provides improved performance over ... Linear Discriminant Analysis (LDA) is one of the principal techniques used in face recognition systems. LDA is well-known scheme for feature extraction and dimension reduction. It provides improved performance over the standard Principal Component Analysis (PCA) method of face recognition by introducing the concept of classes and distance between classes. This paper provides an overview of PCA, the various variants of LDA and their basic drawbacks. The paper also has proposed a development over classical LDA, i.e., LDA using wavelets transform approach that enhances performance as regards accuracy and time complexity. Experiments on ORL face database clearly demonstrate this and the graphical comparison of the algorithms clearly showcases the improved recognition rate in case of the proposed algorithm. 展开更多
关键词 Face recognition principal component analysis (PCA) linear discriminant analysis (LDA) relevance weighted LDA (RW-LDA) LDA/QR wavelet transform sub-bands.
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Analysis on Completeness of Small Earthquake Data in the Northeast Seismic Zone and Its Influence on Seismicity Parameters
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作者 Xie Zhuojuan Lv Yuejun +1 位作者 Peng Yanju Zhang Lifang 《Earthquake Research in China》 2013年第3期370-381,共12页
Taking the northeast seismic zone as an example and based on the magnitude-frequency distribution principles of the G-R relationship and the study on the temporal and spatial distribution characteristics of the minimu... Taking the northeast seismic zone as an example and based on the magnitude-frequency distribution principles of the G-R relationship and the study on the temporal and spatial distribution characteristics of the minimum magnitude of completeness M C in each time interval,this paper makes a statistical analysis on the seismicity parameters of the research area and explores the influence of the completeness of small earthquake data on the seismicity parameters and seismic hazard analysis.It shows that the completeness analysis of the regional small earthquakes data provides a possible means for obtaining more accurate seismicity parameters that can better represent the actual regional seismicity level for areas of low seismicity.The research methods of this article and its conclusion can be used as a reference for the completeness analysis of earthquake data and seismic activity research. 展开更多
关键词 Small earthquake Minimum magnitude of completeness Seismicityparameters Northeast seismic zone
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