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基于Hanning窗的傅里叶变换的火焰探测器算法 被引量:1
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作者 王一博 尤志亚 《机电工程技术》 2024年第12期222-225,共4页
基于Hanning窗的傅里叶变换方法,提出一种应用于双波长红外火焰探测器的具体识别算法,同时进行了系统搭建及软件程序的设计验证。火焰探测器在检测过程中,环境复杂多变,数据不稳定,提取到的特征存在多样性和复杂性等问题,利用Hanning窗... 基于Hanning窗的傅里叶变换方法,提出一种应用于双波长红外火焰探测器的具体识别算法,同时进行了系统搭建及软件程序的设计验证。火焰探测器在检测过程中,环境复杂多变,数据不稳定,提取到的特征存在多样性和复杂性等问题,利用Hanning窗的傅里叶变换方法,提取了火焰红外辐射在不同波段的特性,并在频域中深入分析了火焰的特性,成功提取关键特征,有效提升了红外火焰探测的精确度和灵敏度。与传统方法相比,所提方法展现了更佳的抗干扰性和鲁棒性,显著降低了误报率,对于复杂场景和干扰源表现出稳定性。 展开更多
关键词 火焰探测 傅里叶变换 hanning 双波长 红外辐射
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Risk Factors and Predictive Model for Acute Mountain Sickness among Han Chinese Travelers to Xizang Autonomous Region 被引量:1
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作者 Qianhui Gong Qiong Li +2 位作者 Zhichao Xu Xiaowei Chen Xiaobing Shen 《Biomedical and Environmental Sciences》 2025年第4期506-510,共5页
Acute mountain sickness(AMS) is an illness caused by hypoxia due to rapid ascent to altitudes above 2,500 m. Symptoms include headache,nausea, vomiting, and loss of appetite, all of which usually improve within 1 to 2... Acute mountain sickness(AMS) is an illness caused by hypoxia due to rapid ascent to altitudes above 2,500 m. Symptoms include headache,nausea, vomiting, and loss of appetite, all of which usually improve within 1 to 2 days. However,untreated AMS can progress to life-threatening conditions such as high-altitude cerebral and pulmonary edema(HACE and HAPE, respectively)^([1]). 展开更多
关键词 risk factors han Chinese travelers ALTITUDE HYPOXIA acute mountain sickness ams Xizang Autonomous Region SYMPTOMS acute mountain sickness
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Five novel ZNF469 gene mutations in sporadic keratoconus patients in the Han Chinese population
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作者 CAO Yanna DENG Zhihong +3 位作者 HE Guiyun XIAO Li ZHANG Feng SU Feng 《中南大学学报(医学版)》 北大核心 2025年第6期931-939,共9页
Objective:Keratoconus(KC)is a progressive corneal ectasia disorder,arising from a myriad of causes including genetic predispositions,environmental factors,biomechanical influences,and inflammatory reactions.This study... Objective:Keratoconus(KC)is a progressive corneal ectasia disorder,arising from a myriad of causes including genetic predispositions,environmental factors,biomechanical influences,and inflammatory reactions.This study aims to identify potential pathogenetic gene mutations in patients with sporadic KC in the Han Chinese population.Methods:Twenty-five patients with primary KC as well as 50 unrelated population matched healthy controls,were included in this study to identify potential pathogenic gene mutations among sporadic KC patients in the Han Chinese population.Sanger sequencing and whole-exome sequencing(WES)were used to analyze mutations in the zinc finger protein 469(ZNF469)gene.Bioinformatics analysis was conducted to explore the potential role of ZNF469 in KC pathogenesis.Results:Five novel heterozygous missense variants were identified in KC patients.Among them,2 compound heterozygous variants,c.8986G>C(p.E2996Q)with c.11765A>C(p.D3922A),and c.4423C>G(p.L1475V)with c.10633G>A(p.G3545R),were determined to be possible pathogenic factors for KC.Conclusion:Mutations in the ZNF469 gene may contribute to the development of KC in the Han Chinese population.These mutation sites may provide valuable information for future genetic screening of KC patients and their families. 展开更多
关键词 KERATOCONUS ZNF469 gene MUTATION Sanger sequencing han Chinese population
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Hans Robert Willenegger——AO原则的奠基者
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作者 丁浩秦 李广政 +2 位作者 史浩然 王羽彤 梁学振 《实用骨科杂志》 2025年第9期864-864,共1页
在医学发展史中,骨折治疗从保守的外固定逐渐进步到先进的内固定技术,每步变革都凝聚了医学家的洞察与努力。20世纪50年代,尽管内固定技术已应用于临床,但对复杂骨折的治疗效果仍存在局限。Hans Robert Willenegger教授意识到这一点并... 在医学发展史中,骨折治疗从保守的外固定逐渐进步到先进的内固定技术,每步变革都凝聚了医学家的洞察与努力。20世纪50年代,尽管内固定技术已应用于临床,但对复杂骨折的治疗效果仍存在局限。Hans Robert Willenegger教授意识到这一点并采取了积极的应对措施。他与同行医生们深入交流和探讨,于1958年共同创立了国际内固定协会(the association for the study of internal fixation,ASIF)[1]。Willenegger教授及其团队确立了一套至今仍被广泛采用的骨折管理基本原则,即著名的AO原则。这些原则极大地推动了骨折治疗领域的发展,提高了治疗的科学性和系统性,使患者能够获得更加稳定和有效的治疗方案。 展开更多
关键词 hans Robert Willenegger AO原则
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Research on the Secondary Creation and Artistic Innovation of the Guangdong Han Opera“Wang Zhaojun”
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作者 Bo Dong Ruiji Shengchuan 《Journal of Contemporary Educational Research》 2025年第2期84-89,共6页
Guangdong Han Opera,known as the“Peony of the South,”is a treasured art form with a history of over 300 years.As one of the three major opera genres in Guangdong,it primarily uses Pi and Huang tuning,incorporating K... Guangdong Han Opera,known as the“Peony of the South,”is a treasured art form with a history of over 300 years.As one of the three major opera genres in Guangdong,it primarily uses Pi and Huang tuning,incorporating Kunqu,Gaoqiang,Chuiqiang,and minor tunes,with Zhongzhou rhyme as its stage language.The roles are divided into seven categories:Sheng,Dan,Chou,Gong,Po,and Jing(including Hongjing and Wujing).Its accompaniment instruments,particularly the Touxian,Dasuluo,and Haotou,are distinctive,making it an excellent Pi and Huang opera genre in southern China.In 2008,Guangdong Han Opera was listed in the national intangible cultural heritage,recognizing its artistic value and entrusting it with the mission of inheriting and developing this opera genre.This paper focuses on the Guangdong Han Opera“Wang Zhaojun”and employs methods such as literature review and case analysis to explore its achievements in secondary creation and artistic innovation.The opera has achieved innovations in script,character,music,and stagecraft,and made breakthroughs in performance form,narrative technique,and cultural connotation,promoting the inheritance and development of Guangdong Han Opera and providing insights into contemporary drama innovation. 展开更多
关键词 Guangdong han Opera Wang Zhaojun Secondary creation Artistic innovation
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Hans Chinese consume less O_(2) for muscular work than european-american
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作者 Mei-Han Guo David Montero 《Military Medical Research》 2025年第7期1151-1153,共3页
Dear Editor,The Hans Chinese(HC)ethnic group,comprising approximately 1.4 billion individuals,represents the largest workforce globally.Historically,HC has been predominantly isolated from other ethnic groups for over... Dear Editor,The Hans Chinese(HC)ethnic group,comprising approximately 1.4 billion individuals,represents the largest workforce globally.Historically,HC has been predominantly isolated from other ethnic groups for over 3 millennia,resulting in distinct genetic and physiological characteristics[1,2].Consequently,the energy required to maintain essential functions,represented by the basal metabolic rate(BMR),cannot be accurately assessed in HC with algorithms developed for European-American(EA)populations,even when controlling for diff erences in body size[3].Notably,the widely used Harris-Benedict equation tends to overestimate BMR,relative to measured BMR via indirect calorimetry,in more than 50%of HC individuals[3].Hence,HC generally expends less energy than EA under basal(resting)conditions.This raises an important question:does HC require lower energy expenditure than EA for equivalent external work?Th e present aimed to address this inquiry,while adjusting for key confounding factors such as age,sex,physical activity,aerobic capacity,BMR,and body composition. 展开更多
关键词 hanS CHINESE O_(2) uptake Metabolic cost of exercise Lean BODY mass BODY fat European-American
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Cultural Memory in Sounds:A Musical Anthropological Interpretation of the Newly Composed Guangdong Han Opera“Tianfeng Haiyu Meihuadu”
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作者 Bo Dong Ruiji Shengchuan 《Journal of Contemporary Educational Research》 2025年第2期164-169,共6页
This paper employs the theories and methods of music anthropology to conduct a deep analysis of the newly composed Guangdong Han Opera“Tianfeng Haiyu Meihuadu.”By exploring its musical forms,performance rituals,and ... This paper employs the theories and methods of music anthropology to conduct a deep analysis of the newly composed Guangdong Han Opera“Tianfeng Haiyu Meihuadu.”By exploring its musical forms,performance rituals,and the cultural connotations of the Hakka people,it reveals the unique cultural memory embedded in the musical aspects of the opera.The study finds that“Tianfeng Haiyu Meihuadu”is not only a representative work of the newly composed Guangdong Han Opera but also an important carrier of Hakka cultural inheritance and dissemination.Its music and performance are closely linked to the history,emotions,and social life of the Hakka people,providing a vivid example for understanding the characteristics of Hakka culture and the functions of musical culture. 展开更多
关键词 Guangdong han Opera Tianfeng Haiyu Meihuadu Music anthropology Hakka culture Cultural memory
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Ancient genomes illuminate the demographic history of Shandong over the past two millennia
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作者 Qu Shen Zhigang Wu +18 位作者 Jinguo Zan Xiaomin Yang Jianxin Guo Zhi Ji Baitong Wang Yilan Liu Xiaolu Mao Xinyi Wang Xinyue Zou Hongming Zhou Yanying Peng Hao Ma Haifeng He Tianyou Bai Mengting Xu Shaoqing Wen Li Jin Qun Zhang Chuan-Chao Wang 《Journal of Genetics and Genomics》 2025年第4期494-501,共8页
Shandong province,located in the Lower Yellow River,is one of the birthplaces of ancient Chinese civilization.However,the comprehensive genetic histories of this region have remained largely unknown until now due to a... Shandong province,located in the Lower Yellow River,is one of the birthplaces of ancient Chinese civilization.However,the comprehensive genetic histories of this region have remained largely unknown until now due to a lack of ancient human genomes.Here,we present 21 ancient genomes from Shandong dating from the Warring States period to the Northern Dynasties.Unlike the early Neolithic samples from Shandong,the historical samples are most closely related to post-Late Neolithic populations of the Middle Yellow River Basin,suggesting a population turnover in Shandong from the Neolithic Age to the Historical era.In addition,we detect a close genetic affinity between the historical samples in Shandong and present-day Han Chinese,showing long-term genetic stability in Han Chinese,at least since the Warring States period. 展开更多
关键词 Ancient DNA ShanDONG Yellow River Historical period Population migration Genetic heterogeneity Genetic stability han
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When Traditional Chinese Medicine Meets Western Medicine: The Practice of Scientification in Modern Shang Han Lun Theory
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作者 LI Panfei ZHU Deming 《Chinese Medicine and Culture》 2025年第3期279-292,共14页
Against the backdrop of the modern-era conflict between traditional Chinese medicine(TCM)and Western medicine,during which Western medicine gradually gained administrative authority over public health,Chinese medicine... Against the backdrop of the modern-era conflict between traditional Chinese medicine(TCM)and Western medicine,during which Western medicine gradually gained administrative authority over public health,Chinese medicine faced an existential crisis.Due to Shang Han Lun(《伤寒论》Treatise on Cold Damage)being characterized by its emphasis on clinical efficacy rather than metaphysical speculation,and under the influence of Japanese Kampo medicine,which highly valued the study of Shang Han Lun and promoted Chinese-Western integration,Shang Han Lun Theory emerged as a primary breakthrough point for the scientification of TCM.Modern-era scholars of Shang Han Lun Theory developed innovative interpretations of the six meridians from multiple perspectives,including reinterpretation based on syndromic patterns,organ structures and physiopathological mechanisms,the Stage-based Model,and pathological location and nature.They also incorporated new scientific knowledge such as bacteriology,physiology,pathology,and pharmacology to reinterpret the etiology,medicinals,and formulas within the Shang Han Lun.Moreover,these scholars pioneered the clinical co-application of Western pharmaceuticals with Shang Han Lun–based formulas,introduced Western diagnostic instruments into TCM clinical practice,and explored institutional models of the Integration of TCM and Western Medicine.These innovations and transformations led to the formation of a new research paradigm within Shang Han Lun Theory,which not only countered the criticisms from Western medicine,thereby preserving the academic and clinical space for TCM,but also initiated a new educational model for Shang Han Lun studies.More importantly,it laid a crucial theoretical and practical foundation for the post-1949 development of the Integration of TCM and Western Medicine,marking a significant milestone in the modern history of Chinese medicine. 展开更多
关键词 Shang han Lun(《伤寒论》Treatise on Cold Damage) Shang han Lun Theory(伤寒论学) Scientification Traditional Chinese medicine Western medicine Kampo medicine Modern era
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Ancient DNA reveals genetic exchange in the Hehuang valley in the context of demic diffusion during the Han dynasty
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作者 Langyun Wang Yutong Wang +8 位作者 Bing Sun Daxuan Zhang Guanjin Liang Pengcheng Ma Hao Zhang Chunxiang Li Xiaojun Hu Quanchao Zhang Yinqiu Cui 《Journal of Genetics and Genomics》 2025年第4期592-595,共4页
The Hehuang Valley,situated in the northeastern section of the Qinghai-Tibet Plateau,represents the upper reaches of the Yellow River(Fig.1A).It is a significant geographic region of origin for numerous Neolithic cult... The Hehuang Valley,situated in the northeastern section of the Qinghai-Tibet Plateau,represents the upper reaches of the Yellow River(Fig.1A).It is a significant geographic region of origin for numerous Neolithic cultures,including the Majiayao,Zongri,and Qijia cultures(Dong et al.,2013). 展开更多
关键词 hehuang valley neolithic cultures demic diffusion han dynasty yellow river neolithic culturesincluding ancient dna qinghai tibet plateau
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Origin and Inheritance of Health Preservation Concepts in Treatise on Cold Damage and Miscellaneous Diseases(Shang Han Za Bing Lun)
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作者 Qingya Li Shuohan Su +5 位作者 Qian Wang Long Feng Haiyan Zhang Liran Xu Dongyang Li Xiaodan Yin 《Chinese Medicine and Natural Products》 2025年第3期135-139,共5页
By analyzing the structure and academic characteristics of early Western Han medical texts such as Prescriptions for Fifty-Two Diseases(Wu Shi Er Bing Fang)and Prescriptions for Health Preservation(Yang Sheng Fang),an... By analyzing the structure and academic characteristics of early Western Han medical texts such as Prescriptions for Fifty-Two Diseases(Wu Shi Er Bing Fang)and Prescriptions for Health Preservation(Yang Sheng Fang),and considering the development of philosophical thinking during the pre-Qin and Han periods,this study summarizes how Zhongjing Zhang’s Treatise on Cold Damage and Miscellaneous Diseases(Shang Han Za Bing Lun)inherited pre-Qin and Han philosophical thought while further integrating Daoist“natural law”cosmology,Confucian“benevolence”social ethics,and the“isomorphic unity of heaven and humanity”medical theory in Yellow Emperor’s Inner Classic(Huang Di Nei Jing).It proposes health preservation concepts encompassing heaven-human,body-spirit,and benevolence perspectives,along with dietary hygiene,representing the medical embodiment of pre-Han“virtue cultivation”and“body nurturing”life philosophies that profoundly influenced subsequent traditional Chinese medicine health preservation theory and practice. 展开更多
关键词 health preservation Treatise on Cold Damage and Miscellaneous Diseases Shang han Za Bing Lun Zhongjing Zhang heaven-human view body-spirit concept benevolence concept
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Rethinking Ancient Learning:The Japanese KohōSchool and Medical Knowledge Exchange in Early Modern East Asia
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作者 XIANG Jingjing 《Chinese Medicine and Culture》 2025年第2期181-191,共11页
During the 17th and 18th centuries,medical exchanges between Japan and China were frequent and intensive.In the 17th century,due to the wars during the Ming-Qing transition,numerous Chinese physicians came to Japan,br... During the 17th and 18th centuries,medical exchanges between Japan and China were frequent and intensive.In the 17th century,due to the wars during the Ming-Qing transition,numerous Chinese physicians came to Japan,bringing with them advanced medical techniques and newly published medical texts.In the early 18th century,following Tokugawa Yoshimune’s(徳川吉宗)implementation of medical reform policies,many Chinese physicians arrived in Japan.There,they exchanged knowledge with Japanese physicians and facilitated the publication of Chinese medical texts in Japan.These exchanges significantly increased attention to Chinese medical works,particularly Shang Han Lun(《伤寒论》Treatise on Cold Damage),within Edo medical circles.This had a profound impact on physicians of the Japanese Kohōschool(古方派)and significantly contributed to shaping Kampōmedicine into its contemporary form.From the perspectives of intellectual history and knowledge exchange,this paper explores the circulation of medical knowledge between China and Japan during the early modern period,examining its profound historical influence on Japanese medicine.The study specifically aims to clarify the authentic meaning of“Ancient Learning(复古)”and to correct the prevailing academic misconception that the Kohōschool exclusively focused on reviving Shang Han Lun. 展开更多
关键词 East Asian cultural sphere Medical knowledge Kohōschool(古方派) “Returning to Ancient Learning(复古)” Shang han Lun(《伤寒论》Treatise on Cold Damage)
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Hanning自卷积窗及其在谐波分析中的应用 被引量:83
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作者 温和 滕召胜 卿柏元 《电工技术学报》 EI CSCD 北大核心 2009年第2期164-169,共6页
加窗插值FFT算法可以有效降低频谱泄漏和栅栏效应对谐波分析精度的影响。本文提出一种由Hanning窗进行自卷积运算得到的Hanning自卷积窗,分析了卷积阶数对主瓣宽度、旁瓣电平和旁瓣衰减速率的影响,计算了1~4阶Hanning自卷积窗的主瓣、... 加窗插值FFT算法可以有效降低频谱泄漏和栅栏效应对谐波分析精度的影响。本文提出一种由Hanning窗进行自卷积运算得到的Hanning自卷积窗,分析了卷积阶数对主瓣宽度、旁瓣电平和旁瓣衰减速率的影响,计算了1~4阶Hanning自卷积窗的主瓣、旁瓣性能参数,给出了基于Hanning自卷积窗的双峰插值FFT谐波分析算法。仿真结果表明,Hanning自卷积窗具有优良的频谱抑制性能,基于Hanning自卷积窗的双峰插值FFT算法能有效消除各次谐波间的相互干扰,适合于电力谐波的高精度检测,与已有加窗插值FFT谐波分析算法相比,精度有明显提高,且便于嵌入式系统实现。 展开更多
关键词 hanning自卷积窗 快速傅里叶变换 谐波分析 频谱泄漏
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用加Hanning窗插值高阶正弦拟合法测介损角 被引量:14
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作者 徐志钮 律方成 +1 位作者 汪佛池 李和明 《高电压技术》 EI CAS CSCD 北大核心 2007年第4期50-53,共4页
电力系统频率偏离50Hz时常规的傅立叶变换用于频谱分析时易产生频谱泄漏和栅栏效应,使介损角计算产生误差。高阶正弦拟合法以信号的基波频率、谐波幅值和相角作为变量对信号进行拟合,该法能有效减轻谐波存在和频率波动的影响,精确测量... 电力系统频率偏离50Hz时常规的傅立叶变换用于频谱分析时易产生频谱泄漏和栅栏效应,使介损角计算产生误差。高阶正弦拟合法以信号的基波频率、谐波幅值和相角作为变量对信号进行拟合,该法能有效减轻谐波存在和频率波动的影响,精确测量电气设备的介损角。高阶正弦拟合法的关键是最小二乘的计算,通常使用傅立叶变换结果作为最小二乘法的初始值,当频率偏离50Hz较多时,傅立叶变换结果与谐波分析的真实值相差较大,将其作为初值的最小二乘计算量大,影响了高阶正弦拟合法的实时性。加Hanning窗插值谐波分析法通过加窗和插值能有效减轻频率偏离50Hz时的频谱泄漏和栅栏效应,且有快速算法较之傅立叶变换增加的计算量很少。为提高高阶正弦拟合法计算介损角时的实时性,将加Hanning窗插值谐波分析法的结果作为高阶正弦拟合法的初始值,所得初始值与精确值的差值减少,最小二乘法的迭代次数从2次减到1次,容性设备仿真信号的计算时间从约0.82ms减到约0.45ms,结果表明所提出的方法能有效减少介损角的计算时间,提高介损角测量的实时性。 展开更多
关键词 介损角 测量 hanning 最小二乘法 高阶正弦拟合算法 计算时间
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基于Hanning和Nuttall的混合卷积窗谐波分析方法 被引量:17
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作者 李媛 王海云 +1 位作者 王维庆 裴贝贝 《太阳能学报》 EI CAS CSCD 北大核心 2018年第12期3363-3370,共8页
提出用Hanning窗和Nuttall窗进行卷积构造一种新型的窗函数——混合卷积窗,分析该窗函数的幅频特性,推导出基于混合卷积窗的三谱线插值法。将所提方法用于电力谐波分析,并与加经典窗算法进行对比。仿真分析表明,该混合卷积窗与Hanning窗... 提出用Hanning窗和Nuttall窗进行卷积构造一种新型的窗函数——混合卷积窗,分析该窗函数的幅频特性,推导出基于混合卷积窗的三谱线插值法。将所提方法用于电力谐波分析,并与加经典窗算法进行对比。仿真分析表明,该混合卷积窗与Hanning窗和Nuttall窗相比具有更快的旁瓣衰减速率,能更好抑制频谱泄露。在非同步采样情况下,加混合卷积窗三谱线插值法分析谐波具有更高的计算精度。 展开更多
关键词 FFT 谐波分析 频谱分析 混合卷积窗 hanning Nuttall窗
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半互穿网络HAN基电控固体推进剂力学性能及燃烧启停性能
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作者 奈慧敏 刘富涵 +4 位作者 王斌 夏德斌 张健 林凯峰 杨玉林 《含能材料》 北大核心 2025年第2期188-197,共10页
为了探究黏结剂聚乙烯醇(PVA)聚合度、交联剂硼酸(HB)含量、添加剂聚苯胺(PANI)以及壳聚糖(CTS)对硝酸羟胺基电控固体推进剂(HAN-ECSP)力学性能和燃烧启停性能的影响,采用溶胀法制备试样,通过拉伸测试、燃烧启停性能测试、X射线衍射(XRD... 为了探究黏结剂聚乙烯醇(PVA)聚合度、交联剂硼酸(HB)含量、添加剂聚苯胺(PANI)以及壳聚糖(CTS)对硝酸羟胺基电控固体推进剂(HAN-ECSP)力学性能和燃烧启停性能的影响,采用溶胀法制备试样,通过拉伸测试、燃烧启停性能测试、X射线衍射(XRD)、傅里叶变换红外衰减全反射(FTIR-ATR)、光学电子显微镜对力学性能及燃烧启停性能进行研究。结果表明,不同聚合度PVA结晶度差别不大,PVA聚合度为(2400±50)时,─OH含量相对较多力学性能更好。HB含量影响PVA的交联密度,PVA_(2499)-20%HB致密性相对较差,表面凹陷不平整。PVA_(2499)-18%HB抗拉强度为2.36 MPa,抗拉伸长率为482.92%,力学性能最好,但对铜电极具有较强的腐蚀性。以8%的HB与PVA交联形成第一网络,加入PANI或CTS与PVA形成半互穿聚合物网络,PVA_(2499)-8%HB-2%PANI推进剂抗拉强度为1.03 MPa,抗拉伸长率为432.85%。PVA_(2499)-8%HB-1%CTS推进剂抗拉强度为0.87 MPa,抗拉伸长率为302.28%。添加PANI或CTS的ECSP均可以实现启停,且最高燃烧温度均可以达到800℃。 展开更多
关键词 han-ECSP力学性能 燃烧启停性能 聚乙烯醇聚合度 HB含量 半互穿聚合物网络
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基于加Hanning窗递推DFT算法的测频方法 被引量:10
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作者 许珉 王玺 程凤鸣 《电力自动化设备》 EI CSCD 北大核心 2010年第11期73-74,78,共3页
常用递推离散傅里叶变换(DFT)方式动态计算频谱,根据相位计算结果实时计算电网变化的频率,动态调整测量控制装置的采样频率实现同步采样。但由于截断信号会产生频谱泄漏,使得相位和频率计算结果有一定误差,采用该方法跟踪频率,实时计算... 常用递推离散傅里叶变换(DFT)方式动态计算频谱,根据相位计算结果实时计算电网变化的频率,动态调整测量控制装置的采样频率实现同步采样。但由于截断信号会产生频谱泄漏,使得相位和频率计算结果有一定误差,采用该方法跟踪频率,实时计算电网变化的频率速度较慢。为提高频率跟踪计算速度,对加Hanning窗递推DFT算法计算频率进行了研究,利用2次加Hanning窗递推DFT求出工频基波相位经过1个工频周期后的相位变化量,再利用该变化量求出对应频率的变化量。采用加窗递推DFT有效减小了频谱泄漏的影响,提高了相位差的计算精度和速度,从而可以提高频率的计算精度和速度。该方法简单,易于实现,计算量较小,频率跟踪速度快。 展开更多
关键词 相位差校正法 递推DFT算法 hanning 频谱泄漏 频率
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基于Hanning卷积窗的DFT介质损耗角测量算法 被引量:13
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作者 孙鹏 杨永越 +1 位作者 刘黎明 由广祥 《电测与仪表》 北大核心 2014年第16期73-77,共5页
在高压电气设备介质损耗角在线监测中,DFT算法用于介质损耗角(介损角)测量时,系统频率的波动所造成的非同步采样将会产生泄露效应,从而会影响介损角测量精度。文章详细地分析了DFT算法非同步采样造成的泄露效应,提出了一种基于Hanning... 在高压电气设备介质损耗角在线监测中,DFT算法用于介质损耗角(介损角)测量时,系统频率的波动所造成的非同步采样将会产生泄露效应,从而会影响介损角测量精度。文章详细地分析了DFT算法非同步采样造成的泄露效应,提出了一种基于Hanning卷积窗的DFT介质损耗角测量算法。该算法采用Hanning卷积窗对电流和电压信号进行加权,利用频谱相位差校正法进行频谱校正以获得基波相位,根据电流与电压的基波相位差计算出介损角。通过仿真给出了该算法在电压频率波动和白噪声变化时计算所得介损角的变化情况,通过分析验证了该算法的有效性。 展开更多
关键词 介质损耗角 DFT 非同步采样 泄露效应 hanning卷积窗
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Hanning低通滤波在PSD法测量直管不直度中的应用 被引量:1
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作者 袁红星 王志兴 +1 位作者 李振华 贺安之 《南京理工大学学报》 EI CAS CSCD 1999年第1期81-84,88,共5页
该文介绍了利用PSD测量直管不直度的新颖方法,利用频谱分析的方法分别对不直度理论模型和实验数据作了分析,得出了不直度信号具有低频占优的频谱特征的结论,并由此提出了利用Hanning低通数字滤波器除高频噪声,从而解决了... 该文介绍了利用PSD测量直管不直度的新颖方法,利用频谱分析的方法分别对不直度理论模型和实验数据作了分析,得出了不直度信号具有低频占优的频谱特征的结论,并由此提出了利用Hanning低通数字滤波器除高频噪声,从而解决了直管不直度曲线这种空域信号无法利用电学滤波的困难。 展开更多
关键词 位置传感器 不直度 低通滤波 噪声 PSD 直管
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