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基于改进Hilbert-Huang变换的管路环向裂纹故障诊断研究
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作者 权凌霄 孙世博 +2 位作者 狄梦然 李朋杰 熊国钦 《液压与气动》 北大核心 2024年第4期109-116,共8页
在制造、加工、装配以及服役过程中,航空液压管路可能存在平面型缺陷。在适航载荷作用下,这些缺陷会萌生裂纹并发生扩展,最终导致管路破裂和油液泄漏。为了在管路产生微裂纹时对其进行故障诊断,采用了自行搭建的航空液压管路模态试验平... 在制造、加工、装配以及服役过程中,航空液压管路可能存在平面型缺陷。在适航载荷作用下,这些缺陷会萌生裂纹并发生扩展,最终导致管路破裂和油液泄漏。为了在管路产生微裂纹时对其进行故障诊断,采用了自行搭建的航空液压管路模态试验平台和测控系统,对存在环向裂纹航空液压管路的振动信号进行了采集和预处理。而在对管路振动信号进行分解时,由于经验模态分解(Empirical Mode Decomposition,EMD)算法存在模态混叠问题难以获得准确的本征模态函数(Intrinsic Mode Functions,IMF)。为提高信号处理精度,提出一种基于自适应噪声完备经验模态分解(Complete Ensemble Empirical Mode Decomposition with Adaptive Noise,CEEMDAN)和Hilbert变换理论相结合的改进Hilbert-Huang变换方法对航空液压管路环向裂纹进行故障诊断。研究结果表明,该方法能够更准确地诊断航空液压管路的环向裂纹故障。 展开更多
关键词 航空液压管路 模态分析 改进Hilbert-huang变换 裂纹故障诊断
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Study on multi-target mechanism of Radix et Rhizoma Rhei (Dahuang) and Semen Persicae (Taoren) on adhesion intestinal obstruction based on network pharmacology 被引量:1
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作者 Yin-Zi Yue Li Zeng +2 位作者 Xiao-Peng Wang Yang Zong Shuai Yan 《Traditional Medicine Research》 2019年第4期195-204,共10页
Objective: To explore the mechanism of action of Radix et Rhizoma Rhei (Dahuang)(RERR) and Semen Persicae (Taoren)(SP) on adhesive intestinal obstruction (AIO). Methods: The main targets of the active ingredients of R... Objective: To explore the mechanism of action of Radix et Rhizoma Rhei (Dahuang)(RERR) and Semen Persicae (Taoren)(SP) on adhesive intestinal obstruction (AIO). Methods: The main targets of the active ingredients of RERR and SP were filtered based on the traditional Chinese medicine system pharmacology analysis platform. Cytoscape 3.2.1 was applied to build the ingredient-target network of RERR and SP for AIO. Results: Fifteen active components were predicted from the RERR and SP herb pair, such as aloe-emodin, catechin, rhein, gibberellin (GA) 119, GA120 and GA121. These components were applied to 59 targets mainly involved in many biological processes such as signal transduction, anti-apoptosis, and inflammatory response involved in activating the immune effect. Conclusion: This study proposes the system pharmacology method and identifies the potent combination therapeutic mechanism of RERR and SP for AIO. This strategy will provide a new insight to the study of herb combinations. 展开更多
关键词 RADIX ET rhizoma Rhei (Dahuang) SEMEN Persicae (Taoren) Adhesive intestinal OBSTRUCTION Network PHARMACOLOGY
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Summary of Professor Tong Xiaolin's clinical experience of applying Rhizoma Coptidis(Huang Lian)
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作者 Gu Chengjuan Wang Han +1 位作者 Pang Bing Tong Xiaolin 《World Journal of Integrated Traditional and Western Medicine》 2017年第1期1-5,共5页
With the advantages of less toxicity and side effects, traditional Chinese medicine(TCM) is showing a bright future with a good clinical practice. Chinese herbal medicine, which usually contains various active ingredi... With the advantages of less toxicity and side effects, traditional Chinese medicine(TCM) is showing a bright future with a good clinical practice. Chinese herbal medicine, which usually contains various active ingredients, could provide multiple therapeutic effects. Professor Tong Xiaolin has accumulated abundant experience during many years of clinical practice and applies Rhizoma Coptidis(RC) well with the treatment of diabetes and its complications. Rhizoma coptidis is a classical natural herb which is used frequently by professor Tong Xiaolin. In this review, we summarize Tong Xiaolin's clinical experience of applying Rhizoma Coptidis(Huang Lian) in the treatment of disease from two aspects as well as introducing some traditional Chinese medical theory and clinical experience, with a prospect of guiding clinician to use RC more suitably and reasonably. 展开更多
关键词 rhizoma Coptidis(huang Lian) Tong Xiaolin EXPERIENCE
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Effect of Different Processing Methods on Content ofβ-Asarone in the Zhuang Medicine Rhizoma Acori Tatarinowii
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作者 Peng YANG Jiangcun WEI +5 位作者 Wen ZHONG Xiumei MA Xuelan LUO Peitao XIE Jiabao MA Qian HAN 《Medicinal Plant》 CAS 2020年第5期56-58,共3页
[Objectives]This paper aims to establish a method to simultaneously determine the content ofβ-asarone in Rhizoma Acori Tatarinowii dried by three different methods.[Methods]Reversed-phase high-performance liquid chro... [Objectives]This paper aims to establish a method to simultaneously determine the content ofβ-asarone in Rhizoma Acori Tatarinowii dried by three different methods.[Methods]Reversed-phase high-performance liquid chromatography was used,and the chromatographic conditions were as follows:column,Thermo SCIENTIFIC Hypersil GOLD Dim.(mm);mobile phase,methanol-0.1%phosphoric acid(63∶37);column temperature,30℃;flow rate,1mL/min;detection wavelength,257 nm;sample size,10μL.[Results]The linear range of the injection volume ofβ-asarone was 49.28-246.40μg/mL(R=0.9993);the limit of quantification was 0.85 ng and the detection limit was 0.34 ng;the RSD values of precision,stability and reproducibility tests were all less than 3%;and the sample recovery rate was 98.53%-98.97%(RSD<3.00).The results show that the content ofβ-asarone was highest in shade-dried Rhizoma Acori Tatarinowii.The order ofβ-asarone content was as follows:Rhizoma Acori Tatarinowii dried in shade>Rhizoma Acori Tatarinowii dried at 55℃>Rhizoma Acori Tatarinowii dried at 60℃.[Conclusions]This method is sensitive,reliable,and reproducible.It can be used to simultaneously determine the content ofβ-asarone in Rhizoma Acori Tatarinowii dried by three different methods. 展开更多
关键词 rhizoma Acori Tatarinowii Β-ASARONE Reverse-phase high-performance liquid chromatography Content determination
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A review on pharmacological effects of Rhizoma Coptidis(Huang lian)
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作者 Gu Chengjuan Pang Bing +1 位作者 Wang Han and Tong Xiaolin 《World Journal of Integrated Traditional and Western Medicine》 2016年第2期1-5,共5页
Huang Lian(Rhizoma coptidis, RC), which has effects on clearing damp-heat, quenching fie, and counteracting poison, is a herb frequently used in many traditional formulas. At present, there are many researches on the ... Huang Lian(Rhizoma coptidis, RC), which has effects on clearing damp-heat, quenching fie, and counteracting poison, is a herb frequently used in many traditional formulas. At present, there are many researches on the pharmacological effects of RC. In this review, we summarize the research progress on pharmacological effects of RC from four main aspects, in order to guide clinical application and explore the prospects of the application of RC. 展开更多
关键词 rhizoma Coptidis PHARMACOLOGY Research progress
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Optimization of Extraction Process of Fagopyri Dibotryis Rhizoma by Orthogonal Experiment
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作者 Jian YU 《Medicinal Plant》 2024年第3期26-29,共4页
[Objectives]To optimize the water extraction process of Fagopyri Dibotryis Rhizoma.[Methods]The entropy weight method was used to determine the weight of epicatechin extraction rate and dry extract rate and calculate ... [Objectives]To optimize the water extraction process of Fagopyri Dibotryis Rhizoma.[Methods]The entropy weight method was used to determine the weight of epicatechin extraction rate and dry extract rate and calculate the comprehensive score.The water extraction process of Fagopyri Dibotryis Rhizoma was optimized by orthogonal design with the comprehensive score as the indicator and the amount of water,extraction time and extraction times as the factors.[Results]The optimum extraction process of Fagopyri Dibotryis Rhizoma was as follows:adding 10 times of water,extracting 3 times,and extracting for 60 min each time.[Conclusions]The optimized extraction process is stable and feasible,and can be used for the extraction of Fagopyri Dibotryis Rhizoma. 展开更多
关键词 Fagopyri Dibotryis rhizoma ORTHOGONAL EXPERIMENT EPICATECHIN DRY EXTRACT
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Fingerprint Study of Polygonati Rhizoma with Steaming and Exposing to the Sun Alternatively for Different Times
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作者 Min WANG Chenying YE +3 位作者 Qian WANG Ting HE Shenggao YIN Gailian ZHOU 《Medicinal Plant》 2024年第2期18-20,共3页
[Objectives]To explore the influence of different times of steaming and exposing to the sun on the fingerprint of Polygonati Rhizoma by studying the HPLC fingerprint of Polygonati Rhizoma processed products with diffe... [Objectives]To explore the influence of different times of steaming and exposing to the sun on the fingerprint of Polygonati Rhizoma by studying the HPLC fingerprint of Polygonati Rhizoma processed products with different times of steaming and exposing to the sun,and to provide a basis for the determination of the best processing technology of Polygonati Rhizoma.[Methods]SETSAIL II AQ-C 18(5μm×250 mm×4.6 mm)was used as the column,the column temperature was 30℃,pure water(A)and acetonitrile(B)were eluted gradually,0-10 min,B(5%-10%),10-30 min,B(10%-35%),30-40 min,B(35%-60%),40-45 min,B(60%-100%),flow rate 1 mL/min,absorption wavelength 200 nm.[Results]The relative retained peak area RSDs of the common peaks in the precision,reproducibility and stability tests were all less than 5%.There were 17 common peaks in the fingerprint of nine batches of samples,and the retention time of Peak 2 was basically the same as that of the reference peak of 5-HMF.Peak 4 mainly existed in the chromatogram of Sample 3 to Sample 5,peaks 5 and 11 mainly existed after Sample 3,peaks 9,14 and 16 mainly existed after Sample 6,and peaks 12 and 17 mainly existed after Sample 4.[Conclusions]A total of 17 common peaks were obtained,and the Peak 2 was the designated peak,and the chemical components of each processed product were different. 展开更多
关键词 Polygonati rhizoma PROCESSING HPLC FINGERPRINT
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Traditional Chinese medicine Pien-Tze-Huang ameliorates LPS-induced sepsis through bile acid-mediated activation of TGR5-STAT3-A20 signalling
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作者 Bei Li Yong Zhang +9 位作者 Xinyuan Liu Ziyang Zhang Shuqing Zhuang Xiaoli Zhong Wenbo Chen Yilin Hong Pingli Mo Shuhai Lin Shicong Wang Chundong Yu 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第4期601-614,共14页
Pien Tze Huang(PZH),a class-1 nationally protected traditional Chinese medicine(TCM),has been used to treat liver diseases such as hepatitis;however,the effect of PZH on the progression of sepsis is unknown.Here,we re... Pien Tze Huang(PZH),a class-1 nationally protected traditional Chinese medicine(TCM),has been used to treat liver diseases such as hepatitis;however,the effect of PZH on the progression of sepsis is unknown.Here,we reported that PZH attenuated lipopolysaccharide(LPS)-induced sepsis in mice and reduced LPS-induced production of proinflammatory cytokines in macrophages by inhibiting the activation of mitogen-activated protein kinase(MAPK)and nuclear factor-kappa B(NF-κB)signalling.Mechanistically,PZH stimulated signal transducer and activator of transcription 3(STAT3)phosphorylation to induce the expression of A20,which could inhibit the activation of NF-κB and MAPK signalling.Knockdown of the bile acid(BA)receptor G protein-coupled bile acid receptor 1(TGR5)in macrophages abolished the effects of PZH on STAT3 phosphorylation and A20 induction,as well as the LPS-induced inflammatory response,suggesting that BAs in PZH may mediate its anti-inflammatory effects by activating TGR5.Consistently,deprivation of BAs in PZH by cholestyramine resin reduced the effects of PZH on the expression of phosphorylated-STAT3 and A20,the activation of NF-κB and MAPK signalling,and the production of proinflammatory cytokines,whereas the addition of BAs to cholestyramine resin-treated PZH partially restored the inhibitory effects on the production of proinflammatory cytokines.Overall,our study identifies BAs as the effective components in PZH that activate TGR5-STAT3-A20 signalling to ameliorate LPS-induced sepsis. 展开更多
关键词 Pien Tze huang Bile acids SEPSIS Inflammation TGR5 STAT3-A20 signalling
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Mechanism of Polygoni Cuspidati Rhizoma in treating atherosclerosis based on network pharmacology and molecular docking
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作者 Long Xiong Ting-Ting Liao Qian Zhou 《Integrative Medicine Discovery》 2024年第26期1-11,共11页
Background:The incidence and prevalence of atherosclerosis(AS)is increasing every year and has becoming a major health issue of global concern.Polygoni Cuspidati Rhizoma(PCR)is a Chinese herb that is widely used clini... Background:The incidence and prevalence of atherosclerosis(AS)is increasing every year and has becoming a major health issue of global concern.Polygoni Cuspidati Rhizoma(PCR)is a Chinese herb that is widely used clinically for the treating of AS.However,its pertinent targets and probable mechanisms,still need to be completely explored.Methods:Active compounds and targets for PCR and AS targets were screened using public databases.A“drug-component-disease target”network map was created and analyzed after using the Venn online tool to identify common targets and Cytoscape software to screen drug-disease core targets.Critical targets pathway enrichment analyses are conducted using the Metascape database.Using AutoDock Vina and Pymol software,docking validation and visualization of active components and core targets were carried out.Results:PCR was obtained for ten compounds with 105 AS-related targets.Rhein,quercetin,beta-sitosterol,and luteolin may be drug candidates,and the genes for AKT1,TNF,IL-6,EGFR,TP53,IL-1,RELA,and VEGFA are potential therapeutic targets,according to network analysis.PCR might modulate the AGE/RAGE,PI3K/Akt,IL-17 and NF-ᴋB signaling pathways against the development of AS.Molecular docking indicated that quercetin has high affinity for AKT1 and TNF gene targets.Conclusion:This study provides rare information and scientific basis for further exploration of PC in the treatment of AS. 展开更多
关键词 Polygoni Cuspidati rhizoma ATHEROSCLEROSIS network pharmacology molecular docking
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The impact of^(60)Co-γirradiation on the chemical constituents of Chuanxiong Rhizoma
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作者 Ting-Ting Zhu Wei-Shan Qiu +1 位作者 Rui Gu Shi-Hong Zhong 《Traditional Medicine Research》 2024年第1期23-32,共10页
Background:In order to clarify the inmpat ofγirradiation on the chemical composition of traditional Chinese medicine,this paper carefully choosed Chuanxiong Rhizoma to carry on a demonstration study.Methods:Through a... Background:In order to clarify the inmpat ofγirradiation on the chemical composition of traditional Chinese medicine,this paper carefully choosed Chuanxiong Rhizoma to carry on a demonstration study.Methods:Through a meticulous assessment,a comprehensive comparison was made between the irradiated and unirradiated Chuanxiong Rhizoma samples.The property characteristics were investigated by colorimeter and electronic nose.The changes in chemical structures and contents was analyzed by fourier infrared spectroscopy,high performance liquid chromatography and fingerprinting.In a quest to uncover the presence of any new radiolysis products,cutting-edge techniques like ultra performance liquid chromatography-quadrupole-time of flight-mass spectrometry and gas chromatography-mass spectrometry were employed.Moreover,the difference of antioxidant activity were investigated.Results:The irradiation doses within 12 kGy had no significant effects on the content of the main chemical components,characteristics and in vitro antioxidant activity of Chuanxiong Rhizoma,while changes in some functional groups and degradation of some volatile oil components containing olefins need further study.Conclusion:This study indicates that^(60)Co-γirradiation is a stable method for sterilization of Chuanxiong Rhizoma.It’s also provide a reference for the establishment of irradiation standards for Chuanxiong Rhizoma and other aromatic medicinal plants. 展开更多
关键词 ^(60)Co-γirradiation Chuanxiong rhizoma chemical component comprehensive evaluation
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Exploring the mechanism of active ingredients of Smilacis Glabrae Rhizoma in treating migraine headache through network pharmacology and animal experiments
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作者 Dao-Xian Shu Yan-Yan Chen +3 位作者 Jiao-Rong Wang Ying Wang Yong-Fang Gu Yan-Xin Wang 《Integrative Medicine Discovery》 2024年第18期1-10,共10页
Background:To explore the potential mechanism of action of the active ingredients of Smilacis Glabrae Rhizoma(SGR)in the treatment of migraine using network pharmacology and in vivo experiments.Methods:Through the sea... Background:To explore the potential mechanism of action of the active ingredients of Smilacis Glabrae Rhizoma(SGR)in the treatment of migraine using network pharmacology and in vivo experiments.Methods:Through the search of Traditional Chinese Medicines Systems Pharmacology Database and Analysis Platform,Genecards,Drugbank and other databases,we obtained active ingredients,targets of SGR and related disease targets of migraine,and took the intersection for protein-protein interactions analysis.After constructing the network diagram,network topology analysis was performed to derive the core targets and key active ingredients,and Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed.Finally,molecular docking was performed and validated by in vivo experiments.In vivo experiments,18 male BALB/c mice were selected,and the SGR group was fed with SGR drinking tablet concentrate,and nitroglycerin injection was used to construct a mouse model of migraine.Enzyme-linked immunosorbent assay test was used to detect the levels of TNF-α,IL-1β,IL-6,and AKT1 in plasma.Results:The results showed that the core targets of SGR for the treatment of migraine were TNF-α,IL-1β,IL-6,and AKT1.These core targets and key active ingredients had better binding ability.Compared with the blank group,the number of head scratching in the model group increased.Compared with the model group,there was a significant reduction of the number of head scratching in the SGR group.In comparison with the blank group,the protein level in the plasma in the model group was markedly higher.Compared with the model group,the protein level in the SGR group was significantly lower.Conclusion:SGR has the characteristics of improving migraine based on multi-targets,multi-components and multi-pathways,and the mechanism of action may be related to the inhibition of the release of inflammatory factors,neuron protection,and interference with apoptosis and other processes. 展开更多
关键词 MIGRAINE Smilacis Glabrae rhizoma network pharmacology molecular docking mechanism of effect
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Research Overview of Zhuang Medicine Fumigation Lotions
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作者 Bing QING Jiangcun WEI +6 位作者 Fangmei LI Xianyi SHI Li LONG Xian PENG Meiyan QIU Wen ZHONG Zujie QIN 《Medicinal Plant》 2024年第1期35-37,共3页
At present,there is little research on the application of Zhuang medicine fumigation lotions in skin diseases,and there is no research on related preparation processes and quality standards.In this paper,the character... At present,there is little research on the application of Zhuang medicine fumigation lotions in skin diseases,and there is no research on related preparation processes and quality standards.In this paper,the characteristics of its formulation and the research progress in skin diseases are reviewed,in order to deepen the understanding of Zhuang medicine fumigation lotions and provide a more detailed theoretical basis for its clinical research,development and application. 展开更多
关键词 Zhuang medicine fumigation lotions Ilicis Rotundae Cortex Eiliae Herba Polygoni Perfoliati Herba Rhei Radix Et rhizoma
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Reflections on Studying Huang Di Nei Jing in the West
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作者 Edward Neal 《Chinese Medicine and Culture》 2024年第1期72-76,共5页
Huang Di Nei Jing(《黄帝内经》The Yellow Emperor’s Inner Classic) has been the source text of Chinese medicine knowledge and innovation for over two thousand years. Despite this key relevance, many of its ideas and p... Huang Di Nei Jing(《黄帝内经》The Yellow Emperor’s Inner Classic) has been the source text of Chinese medicine knowledge and innovation for over two thousand years. Despite this key relevance, many of its ideas and practices have proven difficult to understand and implement fully into clinical practice. Cultural and language differences can be compounded with these challenges but may also present new opportunities for advancement and insight when studied by researchers outside of the originating culture. This article introduces the method of Classical-Text Archaeology and delves into the author’s two-decade journey of researching this text, with a discussion on cultural differences and issues of medical scholarship. 展开更多
关键词 huang Di Nei Jing Chinese medicine Nei Jing nature-based medicine Classical text research Global health Medical anthropology Classical-Text Archaeology
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Hilbert-Huang变换与大地电磁噪声压制 被引量:106
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作者 汤井田 化希瑞 +2 位作者 曹哲民 任政勇 段圣龙 《地球物理学报》 SCIE EI CSCD 北大核心 2008年第2期603-610,共8页
大地电磁信号具有非线性、非平稳、非最小相位特征,不符合以Fourier变换为基础的传统功率谱估计的基本要求.Hilbert-Huang变换是近年发展起来的处理非线性、非平稳信号的完全局部时频分析方法.本文在简要介绍Hilbert-Huang变换基本原理... 大地电磁信号具有非线性、非平稳、非最小相位特征,不符合以Fourier变换为基础的传统功率谱估计的基本要求.Hilbert-Huang变换是近年发展起来的处理非线性、非平稳信号的完全局部时频分析方法.本文在简要介绍Hilbert-Huang变换基本原理与算法基础上,以实际数据分析为例,探讨了它在大地电磁信号处理及噪声压制中的应用.提出利用Hilbert时-频能量谱对大地电磁信号进行时段筛选,以提高信号品质,增强数据处理的质量和资料的可解释性.利用经验模态分解方法及其多尺度滤波特征,可以有效地分析MT信号中的噪声分布特征,并进行干扰压制. 展开更多
关键词 Hilbert—huang变换 经验模态分解 固有模态函数 大地电磁 噪声压制
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Hilbert-Huang变换的滤波特性及其应用 被引量:104
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作者 谭善文 秦树人 汤宝平 《重庆大学学报(自然科学版)》 EI CAS CSCD 北大核心 2004年第2期9-12,共4页
Hilbert-Huang变换是最新发展起来的处理非线性非平稳信号的时频分析方法。其基本的实现分为两步,多分辨经验模态分解和瞬时频率的求解,随后可以获得信号的时—频谱。这种方法的关键部分是多分辨经验模态分解,任何复杂的信号都可以分解... Hilbert-Huang变换是最新发展起来的处理非线性非平稳信号的时频分析方法。其基本的实现分为两步,多分辨经验模态分解和瞬时频率的求解,随后可以获得信号的时—频谱。这种方法的关键部分是多分辨经验模态分解,任何复杂的信号都可以分解为有限数目并且具有一定物理意义的固有模态函数。多分辨经验模态分解方法可以解释为以信号极值特征尺度为度量的时空滤波过程。时空滤波器充分保留了信号本身的非线性和非平稳特征,在信号的滤波和去噪中具有很大的优势。文中介绍了Hilbert-Huang变换时空滤波的实现过程,并列举了一些实例,说明了该方法的有效性。 展开更多
关键词 Hilbert—huang变换 时空滤波
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一种基于改进Hilbert-Huang变换的非平稳信号时频分析法及其应用 被引量:33
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作者 毛炜 金荣洪 +1 位作者 耿军平 李家强 《上海交通大学学报》 EI CAS CSCD 北大核心 2006年第5期724-729,共6页
对于非平稳信号时频分析,提出了一种基于改进Hilbert-Huang变换(HHT)的分析方法.根据HHT的已有原理,改进了经验模式分解(EMD)过程中的筛选停止准则,提高了分解精度;给出了Hilbert谱分析的完整过程;以线性调频连续波(FMCW)信号模型作为... 对于非平稳信号时频分析,提出了一种基于改进Hilbert-Huang变换(HHT)的分析方法.根据HHT的已有原理,改进了经验模式分解(EMD)过程中的筛选停止准则,提高了分解精度;给出了Hilbert谱分析的完整过程;以线性调频连续波(FMCW)信号模型作为研究对象,结合改进的EMD分解和完整的Hilbert谱分析,通过分析时频分布特征实现高噪声背景下雷达目标信号的检测以及干扰信号的提取.仿真结果表明了改进后的HHT方法对于低信噪比非平稳信号分析的有效性. 展开更多
关键词 非平稳信号 低信噪比 瞬时频率 Hilbert—huang变换 雷达
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Optimization of RAPD Reaction System on Genomic DNA of Agrocybe chaxingu Huang 被引量:9
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作者 王守现 刘宇 +2 位作者 耿小丽 王兰青 孟莉莉 《Agricultural Science & Technology》 CAS 2008年第3期31-34,共4页
[Objective] The research aimed to screen out optimum RAPD reaction system on genomic DNA of Agrocybe chaxingu Huang.[Method] The single factor experiment was adopted to select the required Mg2+ concentration, template... [Objective] The research aimed to screen out optimum RAPD reaction system on genomic DNA of Agrocybe chaxingu Huang.[Method] The single factor experiment was adopted to select the required Mg2+ concentration, template DNA concentration,primer concentration,dNTPs concentration,Taq enzyme concentration and anneal temperature initially.[Result] The optimum reaction system for RAPD amplification of Agrocybe chaxingu Huang was listed as follows:2.5 μl Buffer, 2 mmol/L Mg2+, 75 ng DNA, 0.5 μmol/L primer, 150 μmol/L dNTPs and 2.0 Taq enzyme.The reaction process was also listed as follows: denaturation for 5 min at 92 ℃,35 cycles(1 min at 92 ℃, 1 min for 35.5 ℃ and elongation for 2 min at 72 ℃),10 min at 72 ℃.[Conclusion] The research provided reference for conducting RAPD analysis of and studying genetic relationship and genetic diversity of Agrocybe chaxingu Huang. 展开更多
关键词 AGROCYBE chaxingu huang RAPD Amplified BAND OPTIMIZATION
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利用Hilbert-Huang变换提取地震信号瞬时参数 被引量:23
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作者 皮红梅 刘财 王典 《石油地球物理勘探》 EI CSCD 北大核心 2007年第4期418-424,共7页
通过Hilbert变换求取的信号瞬时参数并非对任何信号都有物理意义,此法通常要求被分析信号是窄带或平稳的,而且对噪声很敏感。而实际地震信号既非平稳又含有噪声,若在实际应用中不加考虑地对地震信号进行Hilbert变换以求取瞬时参数,这种... 通过Hilbert变换求取的信号瞬时参数并非对任何信号都有物理意义,此法通常要求被分析信号是窄带或平稳的,而且对噪声很敏感。而实际地震信号既非平稳又含有噪声,若在实际应用中不加考虑地对地震信号进行Hilbert变换以求取瞬时参数,这种情况下求取的瞬时参数将缺乏物理意义甚至失真。Hilbert-Huang变换是一种新的分析非平稳非线性信号的方法,它先将信号进行经验模态分解(EMD),形成有限个固有模态函数(IMF)之和,再对固有模态函数作Hilbert变换求取时频谱,求取的时频谱在时域和频域都具有较高的分辨率。本文将Hilbert-Huang变换应用于地震瞬时参数的提取,实例表明,对地震剖面做EMD可以得到不同时间尺度上的特征,Hilbert谱比传统的时频谱在时间和频率域上的分辨率都要高,强反射层在第1阶IMF瞬时频率剖面上比原瞬时频率剖面上表现得更为明显。 展开更多
关键词 Hilbert—huang变换 经验模态分解 地震信号 瞬时频率
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Teager-Huang变换在齿轮裂纹故障诊断中的应用 被引量:13
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作者 李辉 郑海起 唐力伟 《振动.测试与诊断》 EI CSCD 北大核心 2010年第1期1-5,共5页
提出了一种基于Teager-Huang变换的齿轮箱故障诊断方法,该方法综合利用了经验模态分解(empiricalmode decomposition,简称EMD)和Teager能量算子分析技术。由于EMD方法具有自适应的分析能力,首先利用EMD把时间序列信号分解成不同特征时... 提出了一种基于Teager-Huang变换的齿轮箱故障诊断方法,该方法综合利用了经验模态分解(empiricalmode decomposition,简称EMD)和Teager能量算子分析技术。由于EMD方法具有自适应的分析能力,首先利用EMD把时间序列信号分解成不同特征时间尺度的固有模态函数,然后用Teager能量算子计算各固有模态函数的瞬时幅值和瞬时频率,得到Teager-Huang变换时频谱。齿轮箱齿轮裂纹故障振动试验信号的研究结果表明:Teager-Huang变换时频谱优于Hilbert-Huang变换时频谱,能有效地识别齿轮的裂纹故障。 展开更多
关键词 Teager—huang变换 经验模态分解 故障诊断 齿轮 时频分析
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基于RO-SBM的Hilbert-Huang变换端点效应抑制方法 被引量:14
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作者 方琨 王渝 +1 位作者 马利兵 王向周 《振动.测试与诊断》 EI CSCD 北大核心 2013年第2期319-324,344-345,共6页
针对Hilbert-Huang变换方法中由于信号经验模态分解(empirical mode decomposition,简称EMD)过程中所存在的端点效应问题,分析了现有数据延拓方式的利弊,并在基于斜率(slope based method,简称SBM)方法以及改进方法(improved slope base... 针对Hilbert-Huang变换方法中由于信号经验模态分解(empirical mode decomposition,简称EMD)过程中所存在的端点效应问题,分析了现有数据延拓方式的利弊,并在基于斜率(slope based method,简称SBM)方法以及改进方法(improved slope based method,简称ISBM)的基础上提出了一种全新的基于斜率再优化(reoptimization slope based method,简称RO-SBM)方法用于信号序列的极值点延拓,然后对延拓后的数据进行EMD分解,得到相应的本征模函数(intrinsic mode function,简称IMF)分量。数值仿真结果表明,采用基于RO-SBM方法进行数据延拓,相比镜像延拓以及ISBM方法,可以更有效地抑制EMD中的端点效应问题,提升HHT方法的信号分析性能。通过基于RO-SBM方法进行数据延拓的HHT方法准确分离出了某转子系统的局部碰摩径向振动信号中所包含的故障特征分量,并将此方法成功应用于旋转机械故障诊断领域。 展开更多
关键词 旋转机械 端点效应 经验模态分解 Hilbert—huang变换 RO—SBM 故障诊断
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