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南宋石桥——忠义桥小析
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作者 傅宏明 《杭州文博》 2004年第1期8-9,共2页
一、历史、地理环境唐宋时期为古代桥梁发展的全盛时期。石桥墩砌筑工艺的不断改进和日臻完善,为兴建长大桥梁铺平了道路。从此石桥飞跃发展,数量和质量都达到历史高峰。宋室南渡,刺激江浙一带经济畸形发展,带动了桥梁的飞速发展,南宋... 一、历史、地理环境唐宋时期为古代桥梁发展的全盛时期。石桥墩砌筑工艺的不断改进和日臻完善,为兴建长大桥梁铺平了道路。从此石桥飞跃发展,数量和质量都达到历史高峰。宋室南渡,刺激江浙一带经济畸形发展,带动了桥梁的飞速发展,南宋杭城内桥梁有3个代表数目:《乾道临安志》卷二一载有73座,《淳祐临安志》 展开更多
关键词 小析 临安 历史 石桥 时期 道路 畸形发展 桥梁
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小析射全自动层析成像技术
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《青海石油》 2002年第4期84-84,共1页
关键词 小析射全自动层成像技术 地震勘探 地震资料处理 解释
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浅谈BC-3000血球仪分析小红细胞对血小板计数的影响
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作者 胡红梅 夏金花 胡玉玲 《中国医学创新》 CAS 2008年第34期84-84,共1页
近年来,我国临床医学事业取得了飞跃发展,大量先进的自动化仪器取代或部分取代了手工操作和一般仪器,使实验结果更加快速与精准,大大提高了检验水平和质量,但也存在一些弊端,特殊情况下,仍需以手工操作法加以校正。现对笔者所在... 近年来,我国临床医学事业取得了飞跃发展,大量先进的自动化仪器取代或部分取代了手工操作和一般仪器,使实验结果更加快速与精准,大大提高了检验水平和质量,但也存在一些弊端,特殊情况下,仍需以手工操作法加以校正。现对笔者所在科室用深圳BC-3000血球仪分析小红细胞型贫血患者对血小析计数的影响发表一些看法,报告如下。 展开更多
关键词 血球仪 血小板计数 小红细胞 自动化仪器 手工操作 小析计数 医学事业 实验结果
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预稀释标本测定时间对血小板计数的影响
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作者 陈永德 申丽红 +1 位作者 郭洁 蔡志勇 《医学研究通讯》 2000年第8期52-52,共1页
采取手指末梢血20微升加入10毫升稀释液中混匀;再进行1:50000稀释混匀:用F-820血细胞分析仪分别测定,结果显示,血小板计数即刻与2分钟,2分钟与4分钟,经配对比较有显著性差异。4分钟与6分钟,6分钟与8分钟无显著性差异。由此得出结论,使... 采取手指末梢血20微升加入10毫升稀释液中混匀;再进行1:50000稀释混匀:用F-820血细胞分析仪分别测定,结果显示,血小板计数即刻与2分钟,2分钟与4分钟,经配对比较有显著性差异。4分钟与6分钟,6分钟与8分钟无显著性差异。由此得出结论,使用血细胞分析仪对预稀释标本进行血小板计数,可以获得稳定的结果,但标本采取后应至少放置5分钟。 展开更多
关键词 时间血细胞分 小析计数 预稀释标本 测定
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66例慢性原发性血小板减少性紫癜临床疗效观察 被引量:4
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作者 张涛 巫协宁 《上海中医药杂志》 北大核心 1999年第12期16-18,共3页
将 66例慢性原发性血小板减少性紫癜患者随机分为治疗组 (自拟理血升板汤加大剂量维生素C) 36例、对照组 (单用大剂量维生素C) 30例作疗效对比观察。结果 :治疗组显效 6例 ,良效19例 ,进步 8例 ,无效 3例 ,总有效率 91.7% ;对照组良效 7... 将 66例慢性原发性血小板减少性紫癜患者随机分为治疗组 (自拟理血升板汤加大剂量维生素C) 36例、对照组 (单用大剂量维生素C) 30例作疗效对比观察。结果 :治疗组显效 6例 ,良效19例 ,进步 8例 ,无效 3例 ,总有效率 91.7% ;对照组良效 7例 ,进步 11例 ,无效 12例 ,总有效率60 0 %。见效时间治疗组 8.36天 ,对照组 17.33天。 展开更多
关键词 慢性 原发性 小析减少性紫癜 中医药疗法
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Theoretical research on structural damage alarming of long-span bridges using wavelet packet analysis 被引量:5
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作者 丁幼亮 李爱群 缪长青 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期459-462,共4页
The state equation and observation equation of the structural dynamic systems under various analysis scales are derived based on wavelet packet analysis. The time-frequency properties of structural dynamic response un... The state equation and observation equation of the structural dynamic systems under various analysis scales are derived based on wavelet packet analysis. The time-frequency properties of structural dynamic response under various scales are further formulated. The theoretical analysis results reveal that the wavelet packet energy spectrum (WPES) obtained from wavelet packet decomposition of structural dynamic response will detect the presence of structural damage. The sensitivity analysis of the WPES to structural damage and measurement noise is also performed. The transfer properties of the structural system matrix and the observation noise under various analysis scales are formulated, which verify the damage alarming reliability using the proposed WPES with preferable damage sensitivity and noise robusticity. 展开更多
关键词 structural damage alarming wavelet packet analysis wavelet packet energy spectrum long-span bridge
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APPLICATION OF ACOUSTIC EMISSION SENSOR IN DETECTING TOOL BREAKAGE IN MICRO-MILLING 被引量:5
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作者 李亮 包杰 +1 位作者 何宁 于强 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第2期119-124,共6页
Acoustic emission (AE) sensors are used to monitor tool conditions in micro-milling operations. Together with the microphone, the AE sensor can detect the tool breakage more accurately and more effectively by applyi... Acoustic emission (AE) sensors are used to monitor tool conditions in micro-milling operations. Together with the microphone, the AE sensor can detect the tool breakage more accurately and more effectively by applying the wavelet analysis. The processed tool breakage technique by AE sensor is used to perform the wavelet analysis on the experimental data. Results indicate the feasibility of using the AE signals for monitoring the tool condition in micro-milling. 展开更多
关键词 acoustic emissions MICRO-MACHINING tool condition monitoring wavelet analysis
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Morphological Change of Starch Grain Based on Simulated Experiment and its Significance of Agricultural Archaeology——Taking Wheat as an Example 被引量:2
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作者 万智巍 杨晓燕 +1 位作者 马志坤 刘光旭 《Agricultural Science & Technology》 CAS 2011年第11期1621-1624,共4页
[Objective] The aim was to research and identify starch grain microfossil found in archaeological sites in China, and to find appropriate procedures for the starch grain analysis experiment.[Method] Wheat starch grain... [Objective] The aim was to research and identify starch grain microfossil found in archaeological sites in China, and to find appropriate procedures for the starch grain analysis experiment.[Method] Wheat starch grain size distribution was analyzed, and some simulated experiments were carried out, like mortar grinding, ultrasonic treatment, hydrochloric acid and hydrogen peroxide immersion, drying treatment, and so on. [Result] The mean size of wheat starch grains had increased in the growth process. Mortar grinding would make wheat starch grains larger than untreated sample. Long time of ultrasonic treatment can also make the starch grain size larger. 10% HCl and 6% H2O2 would have little effects on morphological feature of wheat starch grains. Low temperature heating did not cause starch grains to be gelatinized. [Conclusion] These experiment results can improve the accuracy of starch grain microfossil identification in the archaeological site. Starch grain analysis may be a utility and effective analytical tool in studying the origin of agriculture and the dispersal of crops in China. 展开更多
关键词 Starch grain analysis WHEAT Morphological change Agricultural archaeology
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Automated Registration for Infrared Image Based on Wavelet Analysis 被引量:5
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作者 钮永胜 倪国强 《Journal of Beijing Institute of Technology》 EI CAS 2000年第1期66-72,共7页
To develop a quick, accurate and antinoise automated image registration technique for infrared images, the wavelet analysis technique was used to extract the feature points in two images followed by the compensation f... To develop a quick, accurate and antinoise automated image registration technique for infrared images, the wavelet analysis technique was used to extract the feature points in two images followed by the compensation for input image with angle difference between them. A hi erarchical feature matching algorithm was adopted to get the final transform parameters between the two images. The simulation results for two infrared images show that the method can effectively, quickly and accurately register images and be antinoise to some extent. 展开更多
关键词 image registration image fusion wavelet analysis infrared image processing
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Available parking space occupancy change characteristics and short-term forecasting model 被引量:5
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作者 季彦婕 王炜 邓卫 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期604-608,共5页
Based on an available parking space occupancy (APSO) survey conducted in Nanjing, China, an APSO forecasting model is proposed. The APSO survey results indicate that the time series of APSO with different time-secti... Based on an available parking space occupancy (APSO) survey conducted in Nanjing, China, an APSO forecasting model is proposed. The APSO survey results indicate that the time series of APSO with different time-sections are periodical and self-similar, and the fluctuation of the APSO increases with the decrease in time-sections. Taking the short-time change behavior into account, an APSO forecasting model combined wavelet analysis and a weighted Markov chain is presented. In this model, an original APSO time series is first decomposed by wavelet analysis, and the results include low frequency signals representing the basic trends of APSO and several high frequency signals representing disturbances of the APSO. Then different Markov models are used to forecast the changes of low and high frequency signals, respectively. Finally, integrating the predicted results induces the final forecasted APSO. A case study verifies the applicability of the proposed model. The comparisons between measured and forecasted results show that the model is a competent model and its accuracy relies on real-time update of the APSO database. 展开更多
关键词 available parking space occupancy change characteristics short-term forecasting wavelet analysis weighted Markov chain
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QTL Mapping of Heading stage for Photoperiodthermo Sensitive Male Sterile Line BS366 in Wheat 被引量:3
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作者 张立平 徐小芹 +2 位作者 赵昌平 苑少华 郭玉平 《Agricultural Science & Technology》 CAS 2010年第6期45-48,共4页
[Objective]The study aimed to map QTLs(Quantitative trait loci)of heading stage for phtopeiod-thermo sensitive male sterile line BS366 in wheat.[Method] A population of 234 doubled haploid derived from the cross bet... [Objective]The study aimed to map QTLs(Quantitative trait loci)of heading stage for phtopeiod-thermo sensitive male sterile line BS366 in wheat.[Method] A population of 234 doubled haploid derived from the cross between BS366 and Baiyu149 was planted in Beijing and Funan in 2007,respectively.We used composite interval mapping(CIM)method to analyse the QTLs for heading stage.[Result]We detected 15 QTLs for heading stage.8 QTLs were detected in both Beijing and Funan,which were located on 1B,2A,2D,3B(2 loci),6B(2 loci)and 7B.A single QTL accounted for 2.42%-10.98% of pheotypic varience.[Conclusion] Eight QTLs which were detected under two environments could be applied for marker-assisted breeding and improvement of BS366.The QTL on chromosome 1B was new for heading stage,which enriches the QTL resource. 展开更多
关键词 Wheat(Triticum aestivum L.) Heading stage QTL
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PCA-CMAC based machine performance degradation assessment 被引量:3
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作者 张蕾 曹其新 +1 位作者 Jay Lee Frank L. Lewis 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期299-303,共5页
A principal component analysis-cerebellar model articulation controller (PCA-CMAC) model is proposed for machine performance degradation assessment.PCA is used to feature selection,which eliminates the redundant inf... A principal component analysis-cerebellar model articulation controller (PCA-CMAC) model is proposed for machine performance degradation assessment.PCA is used to feature selection,which eliminates the redundant information among the features from the sensor signals and reduces the dimension of the input to CMAC.CMAC is used to assess degradation states quantitatively based on its local generalization ability.The implementation of the model is presented and the model is applied in a drilling machine to assess the states of the cutting tool. The results show that the model can assess the wear states quantitatively based on the normal state of the cutting tool.The influence of the quantization parameter g and the generalization parameter r in the CMAC model on the assessment results is analyzed.If g is larger,the generalization ability is better,but the difference of degradation states is not obvious.If r is smaller,the different states are distinct,but memory requirements for storing the weights are larger.The principle for selecting two parameters is that the memory storing the weights should be small while the degradation states should be easily distinguished. 展开更多
关键词 principal component analysis cerebellar model articulation controller (CMAC) performancedegradation assessment
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Integrated interpretation of dual frequency induced polarization measurement based on wavelet analysis and metal factor methods 被引量:2
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作者 韩世礼 张术根 +2 位作者 柳建新 胡厚继 张文山 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第5期1465-1471,共7页
In mineral exploration, the apparent resistivity and apparent frequency (or apparent polarizability) parameters of induced polarization method are commonly utilized to describe the induced polarization anomaly. When... In mineral exploration, the apparent resistivity and apparent frequency (or apparent polarizability) parameters of induced polarization method are commonly utilized to describe the induced polarization anomaly. When the target geology structure is significantly complicated, these parameters would fail to reflect the nature of the anomaly source, and wrong conclusions may be obtained. A wavelet approach and a metal factor method were used to comprehensively interpret the induced polarization anomaly of complex geologic bodies in the Adi Bladia mine. Db5 wavelet basis was used to conduct two-scale decomposition and reconstruction, which effectively suppress the noise interference of greenschist facies regional metamorphism and magma intrusion, making energy concentrated and boundary problem unobservable. On the basis of that, the ore-induced anomaly was effectively extracted by the metal factor method. 展开更多
关键词 dual frequency induced polarization method wavelet analysis metal factor Arabian-Nubian shield volcanogenic massive sulfide deposit
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ONLINE PARSIMONIOUS LEAST SQUARES SUPPORT VECTOR REGRESSION AND ITS APPLICATION 被引量:2
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作者 赵永平 孙健国 王健康 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第4期280-287,共8页
A simple and effective mechanism is proposed to realize the parsimoniousness of the online least squares support vector regression (LS-SVR), and the approach is called the OPLS-SVR for short. Hence, the response tim... A simple and effective mechanism is proposed to realize the parsimoniousness of the online least squares support vector regression (LS-SVR), and the approach is called the OPLS-SVR for short. Hence, the response time is curtailed. Besides, an OPLS-SVR based analytical redundancy technique is presented to cope with the sensor failure and drift problems to guarantee that the provided signals for the aeroengine controller are correct and acceptable. Experiments on the sensor failure and drift show the effectiveness and the validity of the proposed analytical redundancy. 展开更多
关键词 support vector machines SENSORS least squares analytical redundancy aeroengines
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Discussion on Problem of Fermentation Contamination of Heterotrophic Chlorella 被引量:1
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作者 金洪波 毕生雷 +2 位作者 乔建援 刘钺 杜风光 《Agricultural Science & Technology》 CAS 2014年第12期2100-2102,共3页
The contamination reasons were analyzed form the viewpoints of strain preparation, air system, medium and equipment sterilization and pipeline configura- tion. Moreover, the contamination-preventing measures were defi... The contamination reasons were analyzed form the viewpoints of strain preparation, air system, medium and equipment sterilization and pipeline configura- tion. Moreover, the contamination-preventing measures were defined. We also sum- marized the characteristics of bacteria that contaminated the fermentation, as well as checking methods and remedial measures. 展开更多
关键词 Heterotrophic chlorella CONTAMINATION DISCUSSION
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A min-max optimization approach for weight determination in analytic hierarchy process 被引量:10
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作者 孙璐 《Journal of Southeast University(English Edition)》 EI CAS 2012年第2期245-250,共6页
A min-max optimization method is proposed as a new approach to deal with the weight determination problem in the context of the analytic hierarchy process. The priority is obtained through minimizing the maximal absol... A min-max optimization method is proposed as a new approach to deal with the weight determination problem in the context of the analytic hierarchy process. The priority is obtained through minimizing the maximal absolute difference between the weight vector obtained from each column and the ideal weight vector. By transformation, the. constrained min- max optimization problem is converted to a linear programming problem, which can be solved using either the simplex method or the interior method. The Karush-Kuhn- Tucker condition is also analytically provided. These control thresholds provide a straightforward indication of inconsistency of the pairwise comparison matrix. Numerical computations for several case studies are conducted to compare the performance of the proposed method with three existing methods. This observation illustrates that the min-max method controls maximum deviation and gives more weight to non- dominate factors. 展开更多
关键词 analytic hierarchy process rain-max optimization WEIGHT linear programming
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Precipitation sequence of η phase along low-angle grain boundaries in Al-Zn-Mg-Cu alloy during artificial aging 被引量:2
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作者 李茂华 杨延清 +4 位作者 冯宗强 黄斌 罗贤 娄菊红 汝继刚 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第7期2061-2066,共6页
The precipitation sequence of η(MgZn2) phase along low-angle grain boundaries in Al-Zn-Mg-Cu alloy was investigated by examining samples aged at 135 ℃ for various times from 5 min to 6 h. High resolution transmiss... The precipitation sequence of η(MgZn2) phase along low-angle grain boundaries in Al-Zn-Mg-Cu alloy was investigated by examining samples aged at 135 ℃ for various times from 5 min to 6 h. High resolution transmission electron microscopy (HRTEM) observations and energy dispersive X-ray spectroscopy (EDX) analysis indicate that the precipitation sequence of η phase along low-angle grain boundaries should be supersaturated solid solution (SSS)→vacancy-rich clusters (VRC)→GP Ⅱ zones→η'→η. Based on the theory of non-equilibrium grain boundary segregation (NGS) and non-equilibrium grain boundary co-segregation (NGCS), the excessive solute elements gradually segregate to the grain boundaries by the diffusion of the solute-vacancy complex during aging treatment. The grain boundary segregation plays an important role in the nucleation and growth of VRC, GP Ⅱ zones, η' phase as well as η phase. 展开更多
关键词 Al-Zn-Mg-Cu alloy AGING low-angle grain boundaries grain boundary segregation precipitation sequence
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Genome Analysis in Wheat Breeding for Disease Resistance 被引量:2
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作者 刘大钧 《Acta Botanica Sinica》 CSCD 2002年第9期1096-1104,共9页
A brief review on the development of wheat germplasm with introduced powdery mildew and scab resistance from Haynaldia villosa Sch. and Leymus racemosus Lam., Roegneria ciliaris (Trin.) Nevski as well as R. kamoji C. ... A brief review on the development of wheat germplasm with introduced powdery mildew and scab resistance from Haynaldia villosa Sch. and Leymus racemosus Lam., Roegneria ciliaris (Trin.) Nevski as well as R. kamoji C. Koch respectively was made. In the course of germplasm development, genome analysis by means of chromosome banding, genomic in situ hybridization (GISH) or fluorescence in situ hybridization (FISH), molecular markers, particularly restriction fragment length polymorphism (RFLP) coupled with aneuploid analysis was employed for the purpose of improving breeding efficiency. Potential use of such germplasm in wheat breeding practice, basic studies and some related problems were also discussed. 展开更多
关键词 Triticum aestivum wheat relatives powdery mildew resistance scab resistance chromosome banding in situ hybridization molecular marker genome analysis
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The Quality Evaluation of Two Chinese Leading Wheat Varieties in Europe Laboratory
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作者 曹文昕 万映秀 +2 位作者 张琪琪 李炎 张平治 《Agricultural Science & Technology》 CAS 2016年第6期1510-1512,共3页
[Objective] The objective was to research the quality evaluation of Chinese wheat variety which analyzed in Europe laboratory, discuss the quality analysis standard of different countries. [Method] Two leading varieti... [Objective] The objective was to research the quality evaluation of Chinese wheat variety which analyzed in Europe laboratory, discuss the quality analysis standard of different countries. [Method] Two leading varieties (Yangnong19, Jimai22) of Huanghuai wheat area from China were analyzed in Cra-w (Walloon Agricultural Research Centre). [Result] Yannong19 corresponds to amuchstronger flour with a far better gluten quality. It could be used for bread making. It could also be used to produce good quality gluten. Jimai22 is not suitable for bread making but would probably be better for noodles production. [Conclusion] Protein results which come from NIR instrument are over estimating the content. This is probably due to the fact that Europe instruments are calibrated with European wheat. 展开更多
关键词 WHEAT Quality analyze Europe laboratory
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Freak wave simulation based on nonlinear model and the research on the time-frequency energy spectrum of simulation results
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作者 崔成 张宁川 李靖波 《Marine Science Bulletin》 CAS 2011年第1期25-39,共15页
VOF (volume of fluid) method has been used to make the numerical simulation of freak wave come true. The comparisons between the numerical results and linear theoretical results corresponding to Eq.(5) have been c... VOF (volume of fluid) method has been used to make the numerical simulation of freak wave come true. The comparisons between the numerical results and linear theoretical results corresponding to Eq.(5) have been carried out to show that the numerical results have a better exhibition of nonlinear characteristics. Wavelet analysis method has been adopted to investigate the time-frequency energy spectrum of simulation freak waves and the results reveal strong nonlinear interaction enables energy to be transferred to high harmonics during the progress of its formation. Varying water depth can enhance the nonlinear interaction, making much more energy be transferred to high harmonics and freak waves with higher asymmetry be generated. 展开更多
关键词 freak wave numerical simulation wavelet analysis varying water depthtime-frequency energy spectrum
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