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Mathematical theory of signal analysis vs. complex analysis method of harmonic analysis
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作者 QIAN Tao ZHANG Li-ming 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2013年第4期505-530,共26页
We present recent work of harmonic and signal analysis based on the complex Hardy space approach.
关键词 Mobius transform Blaschke form mono-component Hardy space adaptive Fourier decomposi-tion rational approximation rational orthogonal system time-frequency distribution digital signal processing uncertainty principle higher dimensional signal analysis in several complex variables and the Clifford algebrasetting.
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Discovering hidden information of gene ontology based on complex networks analysis 被引量:3
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作者 唐晋韬 王挺 王戟 《Journal of Southeast University(English Edition)》 EI CAS 2010年第1期31-35,共5页
To resolve the ontology understanding problem, the structural features and the potential important terms of a large-scale ontology are investigated from the perspective of complex networks analysis. Through the empiri... To resolve the ontology understanding problem, the structural features and the potential important terms of a large-scale ontology are investigated from the perspective of complex networks analysis. Through the empirical studies of the gene ontology with various perspectives, this paper shows that the whole gene ontology displays the same topological features as complex networks including "small world" and "scale-free",while some sub-ontologies have the "scale-free" property but no "small world" effect.The potential important terms in an ontology are discovered by some famous complex network centralization methods.An evaluation method based on information retrieval in MEDLINE is designed to measure the effectiveness of the discovered important terms.According to the relevant literature of the gene ontology terms,the suitability of these centralization methods for ontology important concepts discovering is quantitatively evaluated.The experimental results indicate that the betweenness centrality is the most appropriate method among all the evaluated centralization measures. 展开更多
关键词 gene ontology complex network analysis centrality measure
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Species distribution of polymeric aluminium ferrum——timed complexation colorimetric analysis method of Al-Fe-Ferron 被引量:8
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作者 Hu, YY Tu, CQ Wu, HH 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第4期418-421,共4页
The effects of the calorimetric buffer solutions were investigated while the two colorimetric reactions of AI-ferron complex and Fe-ferron complex occurred individually, and the effects of the testing wavelength and t... The effects of the calorimetric buffer solutions were investigated while the two colorimetric reactions of AI-ferron complex and Fe-ferron complex occurred individually, and the effects of the testing wavelength and the pH of the solutions were also investigated. A timed complexatian colorimetric analysis method of Al-Fe-ferron in view of the total concentration of {AI + Fe} was then established to determine the species distribution of polymeric Al-Fe. The testing wavelength was recommended at 362 net and the testing pH value was 5. With a comparison of the ratios of n(Al)/n(Fe), the standard adsorption curves of the polymeric Al-Fe solutions were derived from the experimental results. Furthermore, the solutions' composition were carious in both the molar n(Al)/n(Fe) ratios, i.e. 0/0, 5/5, 9/1 and 0/10, and the concentrations associated with the total ( Al + Fe which ranged from 10(-5) to 10(-4) mol/L.. 展开更多
关键词 polymeric aluminum-ferrum species distribution timed complexation colarimetric analysis method Al-Fe-ferron
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Complexity analysis of blast-induced vibrations in underground mining: A case study 被引量:4
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作者 Cardu Marilena Dompieri Mauricio Seccatore Jacopo 《International Journal of Mining Science and Technology》 SCIE EI 2012年第1期125-131,共7页
Blasting in geological bodies is an industrial process acting in an environment characterized by high uncertainties (natural joints, faults, voids, abrupt structural changes), which are transposed into the process par... Blasting in geological bodies is an industrial process acting in an environment characterized by high uncertainties (natural joints, faults, voids, abrupt structural changes), which are transposed into the process parameters (e.g. energetic transfer to rock mass, hole deviations, misfires, vibrations, fly-rock, etc.). The approach to this problem searching for the "optimum" result can be ineffective. The geological environment is marked out by too many uncertainties, to have an "optimum" suitable to different applications. Researching for "Robustness" in a blast design gives rise to much more efficiency. Robustness is the capability of the system to behave constantly under varying conditions, without leading to unexpected results. Since the geology varies from site to site, setting a robust method can grant better results in varying environments, lowering the costs and increasing benefits and safety. Complexity Analysis (C.A.) is an innovative approach to systems. C.A. allows analyzing the Complexity of the Blast System and the criticality of each variable (drilling, charging and initiation parameters). The lower is the complexity, the more robust is the system, and the lower is the possibility of unexpected results. The paper presents the results obtained thanks to the C.A. approach in an underground gypsum quarry (Italy), exploited by conventional rooms and pillars method by drilling and blasting. The application of C.A. led to a reliable solution to reduce the charge per delay, hence reducing the impact of ground vibration on the surrounding structures. The analysis of the correlation degree between the variables allowed recognizing empirical laws as well. 展开更多
关键词 Drilling and blasting complexity analysis Vibrations control
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The Space and Time Features of Global SST Anomalies Studied by Complex Principal Component Analysis
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作者 骆美霞 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1999年第1期3-23,5+9+11+15+17+19+21,共19页
In this paper, the variability characteristics of the global field of sea surface temperature (SST) anomaly are studied by complex principal component (c.p.c.) analysis, whose results are also compared with those of r... In this paper, the variability characteristics of the global field of sea surface temperature (SST) anomaly are studied by complex principal component (c.p.c.) analysis, whose results are also compared with those of real p.c. analysis. The data consist of 40 years of global SST monthly averages over latitudes from 42 5°S to 67 5°N. In the spatial domain, it is found that the distribution of the first complex loading amplitude is characterized by three areas of large values: the first one in the eastern and central equatorial Pacific Ocean, the second one in the northern tropical Indian Ocean and South China Sea, the third one in the northern Pacific Ocean. As it will be explained, this pattern may be considered as representative of El Nio mode. The first complex loading phase pattern shows a stationary wave in the Pacific (also revealed by real p.c. analysis) superimposed to an oscillating disturbance, propagating from the Pacific to Indian or the opposite way. A subsequent correlation analysis among different spatial points allows revealing disturbances actually propagating westward from the Pacific to the Indian Ocean, which could therefore represent reflected Rossby waves, i.e. the west phase of the signals that propagate disturbances of thermal structure in the tropical Pacific Ocean. In the time domain, a relation between the trend of the first complex principal component and the ENSO cycle is also established. 展开更多
关键词 Global sea surface temperature anomalies ENSO complex principal component analysis Travelling disturbances
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Complex Seismic Focus Structure and Earthquake-Triggered Landslide Distribution:Analysis of the 2014 Ludian M_w6.1 Earthquake in Yunnan 被引量:3
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作者 CHEN Xiaoli LIU Chunguo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第2期733-734,共2页
Objective The 2014 Ludian Mw6.1 earthquake in Yunnan occurred in a mountainous area with complex tectonics and topography, which caused serious damage as well as co-seismic landslides of an unusual large scale. Becau... Objective The 2014 Ludian Mw6.1 earthquake in Yunnan occurred in a mountainous area with complex tectonics and topography, which caused serious damage as well as co-seismic landslides of an unusual large scale. Because the suspected seismogenic faults on the surface, distribution of aftershocks and focal mechanism solutions are not consistent, it remains difficult to determine what is the real causal fault or seismogenic structure for this event. Actually, it may imply the complicity of the seismic source at depth. In addition, the distribution of the co- seismic landslides also exhibits some diffusion that is different from general eases, likely associated with the seismic focus structure. 展开更多
关键词 complex Seismic Focus Structure and Earthquake-Triggered Landslide Distribution:analysis of the 2014 Ludian M_w6.1 Earthquake in Yunnan
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A ca. 2.2Ga Acidic Magmatic Event at the Northern Margin of the Yangtze Craton: Evidence from U-Pb Dating and Hf Isotope Analysis of Zircons from the Kongling Complex 被引量:2
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作者 XU Daliang WEI Yunxu +3 位作者 PENG Lianhong DENG Xin HU Kun LIU Hao 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第2期872-873,共2页
Objective The Yangtze craton collisional orogeny at ca. extensional events at ca. 1 experienced Paleoproterozoic 1.95-2.0 Ga and post-orogenic 85 Ga related to amalgamation of the Columbia (Nuna) supercontinent (Zh... Objective The Yangtze craton collisional orogeny at ca. extensional events at ca. 1 experienced Paleoproterozoic 1.95-2.0 Ga and post-orogenic 85 Ga related to amalgamation of the Columbia (Nuna) supercontinent (Zhao and Cawood, 2012). A ca. 2.15 Ga suprasubduction zone ophiolitic melange was recongized in the Archean- Paleoproterozoic Kongling Complex of the northern Yangtze craton (Han et al., 2017). However, the tectonic evolution in early Paleoproterozoic from 2.4 Ga to 2.2 Ga remains unclear. We report here the presence of a suite of Paleoproterozoic (2.2 Ga) granites in the Huangling dome, northern Yangtze craton, which may provide important insights into crustal growth processes in the craton prior to the assembly of Columbia. 展开更多
关键词 Pb HF Acidic Magmatic Event at the Northern Margin of the Yangtze Craton Evidence from U-Pb Dating and Hf Isotope analysis of Zircons from the Kongling complex Ga
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Theoretical convergence analysis of complex Gaussian kernel LMS algorithm
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作者 Wei Gao Jianguo Huang +1 位作者 Jing Han Qunfei Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第1期39-50,共12页
With the vigorous expansion of nonlinear adaptive filtering with real-valued kernel functions,its counterpart complex kernel adaptive filtering algorithms were also sequentially proposed to solve the complex-valued no... With the vigorous expansion of nonlinear adaptive filtering with real-valued kernel functions,its counterpart complex kernel adaptive filtering algorithms were also sequentially proposed to solve the complex-valued nonlinear problems arising in almost all real-world applications.This paper firstly presents two schemes of the complex Gaussian kernel-based adaptive filtering algorithms to illustrate their respective characteristics.Then the theoretical convergence behavior of the complex Gaussian kernel least mean square(LMS) algorithm is studied by using the fixed dictionary strategy.The simulation results demonstrate that the theoretical curves predicted by the derived analytical models consistently coincide with the Monte Carlo simulation results in both transient and steady-state stages for two introduced complex Gaussian kernel LMS algonthms using non-circular complex data.The analytical models are able to be regard as a theoretical tool evaluating ability and allow to compare with mean square error(MSE) performance among of complex kernel LMS(KLMS) methods according to the specified kernel bandwidth and the length of dictionary. 展开更多
关键词 nonlinear adaptive filtering complex Gaussian kernel convergence analysis non-circular data kernel least mean square(KLMS).
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Measuring air traffic complexity based on small samples 被引量:8
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作者 Xi ZHU Xianbin CAO Kaiquan CAI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第4期1493-1505,共13页
Air traffic complexity is an objective metric for evaluating the operational condition of the airspace. It has several applications, such as airspace design and traffic flow management.Therefore, identifying a reliabl... Air traffic complexity is an objective metric for evaluating the operational condition of the airspace. It has several applications, such as airspace design and traffic flow management.Therefore, identifying a reliable method to accurately measure traffic complexity is important. Considering that many factors correlate with traffic complexity in complicated nonlinear ways,researchers have proposed several complexity evaluation methods based on machine learning models which were trained with large samples. However, the high cost of sample collection usually results in limited training set. In this paper, an ensemble learning model is proposed for measuring air traffic complexity within a sector based on small samples. To exploit the classification information within each factor, multiple diverse factor subsets(FSSs) are generated under guidance from factor noise and independence analysis. Then, a base complexity evaluator is built corresponding to each FSS. The final complexity evaluation result is obtained by integrating all results from the base evaluators. Experimental studies using real-world air traffic operation data demonstrate the advantages of our model for small-sample-based traffic complexity evaluation over other stateof-the-art methods. 展开更多
关键词 Air traffic control Air traffic complexity Correlation analysis Ensemble learning Feature selection
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Core acupoints of acupuncture for hyperplasia of mammary gland: a network analysis 被引量:1
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作者 Bao-Min Dou Yuan-Yuan Sun +4 位作者 Tian-Yi Zhao Qian-Nan Jia Jiang Liu Bo Chen Yi Guo 《TMR Non-Drug Therapy》 2020年第1期12-22,共11页
Backgroud:Clinical studies on acupuncture treatment of hyperplasia of mammary gland(HMG)have proved its effectiveness,but most studies have paid little attention to acupoints prescription and acupoint compatibility.Th... Backgroud:Clinical studies on acupuncture treatment of hyperplasia of mammary gland(HMG)have proved its effectiveness,but most studies have paid little attention to acupoints prescription and acupoint compatibility.The clinical prescription is not identical,the curative effect also has the difference.Therefore,through data mining and network analysis,this study explored the core acupoints and the compatibility law of acupoints in acupuncture treatment of HMG.Methods:To search and select qualified literature according to inclusion and exclusion criteria for relevant clinical research literature on acupuncture treatment of HMG in CNKI,VIP database,WanFang database and PubMed,etc.Then extract relevant information and establish a database.Using the method of statistical and complex network analysis,this paper studies the core acupoints and the law of acupoint compatibility.Results:A total of 104 Chinese literatures and 0 English literatures were included and 106 acupuncture prescriptions were extracted.The core acupoints in the treatment of HMG are Danzhong(CV 17),Wuyi(ST 15),Zusanli(ST 36),Jianjing(GB 21).Danzhong(CV 17)and Zusanli(ST 36),Danzhong(CV 17)and Wuyi(ST 15),Jianjing(GB 21)and Tianzong(SI 11),Jianjing(GB 21)and Wuyi(ST 15)have the highest correlation degree.The method of acupoint matching mainly consists of local-remote acupoints,upper-lower acupoints and front-rear acupoints.Conclusion:The results of a network analysis substantially accord with the general rules of acupuncture theories in traditional Chinese medicine,able to reflect the points-selection principles and features in acupuncture treatment of HMG and provide evidence for the acupoints selection in the treatment of HMG in acupuncture clinic. 展开更多
关键词 Hyperplasia of mammary glands(HMG) Acupoints compatibility complex network analysis Traditional Chinese medicine
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Geometric morphometric and molecular evidence suggest a new fruit fly species in Bactrocera(Zeugodacus) tau complex(Diptera: Tephritidae) 被引量:2
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作者 Jingyoh Zaelor Sangvorn Kitthawee 《Zoological Systematics》 CSCD 2018年第1期27-36,共10页
Fruit flies in Bactrocera tau complex are important pests, but their morphological taxonomy is still unsettled. In this paper, specimens from gac fruits(Momordica cochinchinensis) are attempted to classify by geomet... Fruit flies in Bactrocera tau complex are important pests, but their morphological taxonomy is still unsettled. In this paper, specimens from gac fruits(Momordica cochinchinensis) are attempted to classify by geometric morphometric and genetic analyses. Geometric morphometric study of wing venation and aculeus shape among samples suggested a new species in this taxon. Sequences in the cytochrome oxidase I region were compared with reference material in this complex, as well as other taxa within the same subgenus. Phylogenetic analysis based on COI revealed a new species of the B. tau complex, B. tau form J. Therefore, the criteria of body color patterns proved to be taxonomically valid for species classification and identification in this species complex. 展开更多
关键词 GM analysis wing venation trilobed aculeus COI Bactrocera tau complex
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COMPLEX NUMBER MODE APPROACH FOR REDUCING VIBRATION OF STRUCTURAL FLEXIBLE REDUNDANT ROBOT MANIPULATORS
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作者 Wu Licheng Sun Zengqi Sun Fuchun Department of Computer Science and Technology, Qinghua University Lu Zhen Yu Shouqian Zheng Hong Beijing University of Aeronautics and Astronautics 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2001年第2期102-105,共4页
A complex number mode analysis approach is proposed for vibration reducing of structural flexible redundant manipulators by utilizing self motion. In the proposed approach, the self motion is evaluated to nullify th... A complex number mode analysis approach is proposed for vibration reducing of structural flexible redundant manipulators by utilizing self motion. In the proposed approach, the self motion is evaluated to nullify the modal exciting force of flexural motion, and the approach can be freely used when the degree of freedom of flexural motion is much greater than the available degree of reundancy. The availability and effectiveness of the proposed approach are demonstrated through numerical simulation with a four link spatial robotic manipulator possessing an end flexible link. 展开更多
关键词 Redundant manipulators SELF MOTION Vibration reducing complex number mode analysis
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Paleoclimate Study of Mountain Ecosystems by Multiple Group Biological Analysis
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作者 Marina SKRYPNIKOVA Olga USPENSKAYA Olga KHOKHLOVA 《Journal of Mountain Science》 SCIE CSCD 2011年第1期24-36,共13页
Methodological problems of climatic reconstruction for different periods of Holocene are discussed on the basis of a multiple group biological analysis on peat-sapropel sediments. The possibility of biological analysi... Methodological problems of climatic reconstruction for different periods of Holocene are discussed on the basis of a multiple group biological analysis on peat-sapropel sediments. The possibility of biological analysis is exemplified by the paleoclimatic reconstruction for Carpathian and Altai Mountain ranges. For the "Skolevsky Beskidy" national park of Carpaty the paleoclimatic scenarios have been drown up aiming at the more precise definition of climatic conditions for the period of mass mountain slope terracing. The stability of terrace systems of various designs in the current climatic conditions has been assessed. It is shown that during periods of humid climate the terraces, whose designs have been focused on drainage, were built. In periods of dry and warm climate the terrace systems capable of accumulating water were built. Both these types of terrace systems are destroyed in nowadays. Only those terrace systems are stable which were adjusted by their builders to contrast variations of precipitation. For Western Altais the paleoclimatic scenario has been done to forecast the safety of the Bronze Age kurgans (burial earth mounds) with permafrost inside the construction. In the Altay region during the Holocene it has revealed two periods of sharp cooling, the peaks of which occurred in the intervals 4500- 4300 and 2500-2300 years pronounced climatic drying ago, and two periods of 4900-4700 and 130-70 years ago. Depletion of the algae composition in the layer corresponding to the last period of drying climate indicates a very sharp change in the parameters of moisture and turning the lake into a dry swamp. Periods of cold weather may have contributed to the formation of special ritual traditions of the Sakan tribes that require the frozen ground to bury the dead. The later climate fluctuations identified have not affected the safety of permafrost in burial mounds constructed in the V-III cc BC. 展开更多
关键词 Climatic reconstruction complex group biological analysis of peat-sapropel sediments PALEOPEDOLOGY Soil evolution HOLOCENE
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SPECTROSCOPIC STUDY AND APPLICATION ON THE INCLUSION COMPLEXATION β-CYCLODEXTRIN WITH ESTRADIOL BENZOATE IN AQUEOUS SOLUTION
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作者 Yao Lifeng,Luo Zhaofu,Ma Hongyan,Pan Zuting(Department of Chemistry, Wuhan University, Wuhan 430072,China) 《Wuhan University Journal of Natural Sciences》 CAS 1998年第1期101-101,共1页
The inclusion complexation reaction of β-cyclodextrin with estradiol benzoate (EB) in the presence ofcetyltrimethylammonium bromide has been studied by means of UV absorption and fluorescent spectrometry. The reactio... The inclusion complexation reaction of β-cyclodextrin with estradiol benzoate (EB) in the presence ofcetyltrimethylammonium bromide has been studied by means of UV absorption and fluorescent spectrometry. The reaction conditions, the formation constant, the mechanism of the host-vip inclusion complexhave been studied and a simple, highly sensitive fluorescent synergistic method for the determination of EBhas been established with satisfactory results. 展开更多
关键词 Β-CYCLODEXTRIN estradiol benzoate cetyltrimethylammoinum bromide spectral analysis inclusion complexation
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Adapting Nanotech Research as Nano-Micro Hybrids Approach Biological Complexity,A Review
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作者 Sascha Vongehr Shaochun Tang Xiangkang Meng 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2016年第5期387-401,共15页
Today's emergence of nano-micro hybrid structures with almost biological complexity is of fundamental interest. Our ability to adapt intelligently to the challenges has ramifications all the way from fundamentally ch... Today's emergence of nano-micro hybrid structures with almost biological complexity is of fundamental interest. Our ability to adapt intelligently to the challenges has ramifications all the way from fundamentally changing research itself, over applications critical to future survival, to posing globally existential dangers. Touching on specific issues such as how complexity relates to the catalytic prowess of multi-metal compounds, we discuss the increasingly urgent issues in nanotechnology also very generally and guided by the motto 'Bio Is Nature's Nanotech'. Technology belongs to macro-evolution; for example integration with artificial intelligence (AI) is inevitable. Darwinian adaptation manifests as integration of complexity, and awareness of this helps in developing adaptable research methods that can find use across a wide range of research. The second half of this work reviews a diverse range of projects which all benefited from 'playful' programming aimed at dealing with complexity. The main purpose of reviewing them is to show how such projects benefit from and fit in with the general, philosophical approach, proving the relevance of the 'big picture' where it is usually disregarded. 展开更多
关键词 complex hybrid structures Catalysis Macro-evolution Optimization Image analysis Simulation Statistical analysis Error analysis Critique of technology
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Arrhythmia Detection by Using Chaos Theory with Machine Learning Algorithms
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作者 Maie Aboghazalah Passent El-kafrawy +3 位作者 Abdelmoty M.Ahmed Rasha Elnemr Belgacem Bouallegue Ayman El-sayed 《Computers, Materials & Continua》 SCIE EI 2024年第6期3855-3875,共21页
Heart monitoring improves life quality.Electrocardiograms(ECGs or EKGs)detect heart irregularities.Machine learning algorithms can create a few ECG diagnosis processing methods.The first method uses raw ECG and time-s... Heart monitoring improves life quality.Electrocardiograms(ECGs or EKGs)detect heart irregularities.Machine learning algorithms can create a few ECG diagnosis processing methods.The first method uses raw ECG and time-series data.The second method classifies the ECG by patient experience.The third technique translates ECG impulses into Q waves,R waves and S waves(QRS)features using richer information.Because ECG signals vary naturally between humans and activities,we will combine the three feature selection methods to improve classification accuracy and diagnosis.Classifications using all three approaches have not been examined till now.Several researchers found that Machine Learning(ML)techniques can improve ECG classification.This study will compare popular machine learning techniques to evaluate ECG features.Four algorithms—Support Vector Machine(SVM),Decision Tree,Naive Bayes,and Neural Network—compare categorization results.SVM plus prior knowledge has the highest accuracy(99%)of the four ML methods.QRS characteristics failed to identify signals without chaos theory.With 99.8%classification accuracy,the Decision Tree technique outperformed all previous experiments. 展开更多
关键词 ECG extraction ECG leads time series prior knowledge and arrhythmia chaos theory QRS complex analysis machine learning ECG classification
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Evolution of the rare earth trade network:A perspective of dependency and competition 被引量:1
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作者 Jilan Xu Jiahao Li +1 位作者 Vincent Charles Xin Zhao 《Geoscience Frontiers》 SCIE CAS CSCD 2024年第3期183-191,共9页
As a global strategic reserve resource,rare earth has been widely used in important industries,such as military equipment and biomedicine.However,existing analyses based solely on the total volume of rare earth trade ... As a global strategic reserve resource,rare earth has been widely used in important industries,such as military equipment and biomedicine.However,existing analyses based solely on the total volume of rare earth trade fail to uncover the underlying competition and dependency dynamics.To address this gap,this paper employs the principles of trade preference and import similarity to construct dependency and competition networks.Complex network analysis is then employed to study the evolution of the global rare earth trade network from 2002 to 2018.The main conclusions are as follows.The global rare earth trade follows the Pareto principle,and the trade network shows a scale-free distribution.China has emerged as the world’s largest importer and exporter of rare earth since 2017.In the dependency network,China has become the most dependent country since 2006.The result of community division shows that China has separated from the American community and formed new communities with the Association of Southeast Asian Nations(ASEAN)countries.The United States of America has formed a super-strong community with European and Asian countries.In the competition network,the distribution of competition intensity follows a scale-free distribution.Most countries face low-intensity competition,but there are numerous competing countries.The competition related to China has increased significantly.Lastly,the competition source for the United States of America has shifted from Mexico to China,resulting in China,the USA,and Japan becoming the core participants in the competition network. 展开更多
关键词 Rare earth Trade network DEPENDENCY COMPETITION complex network analysis
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Optimizing Connections:Applied Shortest Path Algorithms for MANETs
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作者 Ibrahim Alameri Jitka Komarkova +2 位作者 Tawfik Al-Hadhrami Abdulsamad Ebrahim Yahya Atef Gharbi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期787-807,共21页
This study is trying to address the critical need for efficient routing in Mobile Ad Hoc Networks(MANETs)from dynamic topologies that pose great challenges because of the mobility of nodes.Themain objective was to del... This study is trying to address the critical need for efficient routing in Mobile Ad Hoc Networks(MANETs)from dynamic topologies that pose great challenges because of the mobility of nodes.Themain objective was to delve into and refine the application of the Dijkstra’s algorithm in this context,a method conventionally esteemed for its efficiency in static networks.Thus,this paper has carried out a comparative theoretical analysis with the Bellman-Ford algorithm,considering adaptation to the dynamic network conditions that are typical for MANETs.This paper has shown through detailed algorithmic analysis that Dijkstra’s algorithm,when adapted for dynamic updates,yields a very workable solution to the problem of real-time routing in MANETs.The results indicate that with these changes,Dijkstra’s algorithm performs much better computationally and 30%better in routing optimization than Bellman-Ford when working with configurations of sparse networks.The theoretical framework adapted,with the adaptation of the Dijkstra’s algorithm for dynamically changing network topologies,is novel in this work and quite different from any traditional application.The adaptation should offer more efficient routing and less computational overhead,most apt in the limited resource environment of MANETs.Thus,from these findings,one may derive a conclusion that the proposed version of Dijkstra’s algorithm is the best and most feasible choice of the routing protocol for MANETs given all pertinent key performance and resource consumption indicators and further that the proposed method offers a marked improvement over traditional methods.This paper,therefore,operationalizes the theoretical model into practical scenarios and also further research with empirical simulations to understand more about its operational effectiveness. 展开更多
关键词 Dijkstra’s algorithm optimization complexity analysis shortest path first comparative algorithm analysis nondeterministic polynomial(NP)-complete
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Subsynchronous Oscillation Characteristics for Direct Drive Wind Farm Based on Complex Torque Coefficient Method
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作者 Wenchao Zhai Qi Jia Gangui Yan 《CSEE Journal of Power and Energy Systems》 2025年第4期1523-1532,共10页
Based on subsynchronous oscillation(SsO)caused by the connection of a direct drive wind farm to a weak alternating current(AC)grid,a complex torque model is proposed.By dividing the wind farm into a direct current cap... Based on subsynchronous oscillation(SsO)caused by the connection of a direct drive wind farm to a weak alternating current(AC)grid,a complex torque model is proposed.By dividing the wind farm into a direct current capacitor and electrical control part,the analytical expression of damping torque for the electrical control part is deduced and the mechanism of system subsynchronous oscillation is analyzed from the perspective of damping.The system stability is determined based on a damping coefficient less than O,and the influence laws of grid strength,operating conditions,and control parameters on system damping characteristics are analyzed,based on additional subsynchronous oscillation damping control(SSDC)to suppress SsO.Furthermore,the complex torque model of the parallel access system for multiple sub-wind farms is established,and the dynamic interaction between multiple sub-wind farms is preliminarily explored.The time-domain simulation model is built in EMTDC/PSCAD to verify the correctness of the theoretical analysis. 展开更多
关键词 complex torque analysis damping coefficient drive PMSG based wind farm subsynchronous oscillation weak AC grid
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ON A PROBLEM OF F.GROSS
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作者 方明亮 徐万松 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1995年第2期203-205,共3页
This paper deals with the problem of uniqueness of meromorphic functions with two deficient values and obtains a result which is an improvement of that of F.Gross and Yi Hongxun.
关键词 complex analysis meromorphic functions UNIQUENESS deficient value shared value
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