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舰船辐射噪声的高阶统计量特征提取及特征压缩

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应用声学 2010年第6期29卷 466-470页

作者：陈凤林林正青彭圆牟林张凤珍王磊水下测控技术国防科技重点实验室大连116013

提取了6类水中目标的11/2谱统计线谱特征和AR模型特征。实验结果表明基于11/2谱的统计线谱特征和AR模型特征有效的识别出了目标,达到了85%的综合识别率。最后利用主元分析技术对上述特征进行了压缩,在保持识别率的同时将特征维数从64维... 详细信息

提取了6类水中目标的11/2谱统计线谱特征和AR模型特征。实验结果表明基于11/2谱的统计线谱特征和AR模型特征有效的识别出了目标,达到了85%的综合识别率。最后利用主元分析技术对上述特征进行了压缩,在保持识别率的同时将特征维数从64维压缩至34维,有利于工程上的实现。

关键词：舰船辐射噪声高阶统计量特征提取特征压缩 radiated noise ship statistical characteristics 模型特征主元分析技术特征和识别率线谱特征维数水中目标实验结果谱统计综合工程

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Applying a Step Approach Method in Solving the Multi-Frequency Radiation From a Complex Obstacle

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Computer Modeling in Engineering & Sciences 2016年第7期112卷 59-73页

作者： Jui-Hsiang Kao Department of Systems Engineering and Naval Architecture National Taiwan Ocean UniversityKeelungTaiwanR.O.C

In this paper,a step approach method in the time domain is developed to calculate the radiated waves from an arbitrary obstacle pulsating with multiple *** computing scheme is based on the Boundary Integral Equation and derived in the time domain;thus,the time-harmonic Neumann boundary condition can be *** the present method,the values of the initial conditions are set to zero,and the approach process is carried forward in a loop from the first time step to the *** each time step,the radiated pressure on each element is *** several loops,the correct radiated pressures can be obtained.A sphere pulsating with a monopole frequency in an infinite acoustic domain is calculated *** result is compared with the analytical solution,and both of them are in good ***,a complex-shaped radiator is taken as the studied *** pulsating frequency of this case is multiple,and the waves propagate in half *** is shown that the present method can treat multiple-frequency pulsation well,even when the radiator is a complex shape,and a robust convergence can be attained quickly.

关键词： Step approach method Time domain radiated waves Multiple frequencies Boundary integral equation Neumann boundary condition

SOUND RADIATION FROM PLATES ON ELASTIC FOUNDATION UNDER ACTION OF MOVING LINE FORCES

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Journal of China Textile University(English Edition) 1989年第1期7卷 82-94页

作者：彭宏 Mechanical and Aerospace Engineering Department North Carolina State University

An analysis is made of the problem of sound radiation from infinite one-dimensional plateson elastic foundation, when the plates are subjected to the action of harmonic line forces movingat subsonic speeds (M radiatedsound power is shown as a function of the stiffness of elastic foundation, in terms of stiffness fac-torψ, the moving speed of line force, in terms of Math number M, and the frequency, in termsof wavenumber ratio γ . The effects of the parameter ψ in conjunction with the parameters Mand γ on the radiated sound power level and the phenomenon of coincidence radiation are alsoinvestigated in detail.

关键词： infinite dimensional plates (structure) elastic foundation mach number stiffness resonance frequency coincidence phenomenon moving harmonic line force radiated sound power

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Testing the Scaling Law of Earthquake Energy in the View of Broadband Seismology

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Chinese Science Bulletin 1994年第23期39卷 1994-1997页

作者：吴忠良高原 Institute of Geophysics State Seismological Bureau Beijing 100081 PRC Center for Analysis and Prediction State Seismological Bureau Beijing 100036 PRC

In the physics of nonlinear phenomena associated with earthquakes, there is one deduction which is commonly cited without hesitation. Starting from the GutenbergRichter’s

关键词： scaling law radiated energy of earthquakes broadband seismology.

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草菇菌丝体辐射处理后代子实件多酚氧化酶活性检测

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中国食用菌 1987年第2期 6-7页

作者：李家慎朱志强朱坚福建农学院园艺系福建农学院园艺系福州

草菇菌丝体经CO605,000仑琴辐射后,其后代子实体发现明显变化,主要表现在子实体形状和颜色上的变化,试图通过测定多酚氧化酶活性的变化,了解辐射对草菇代谢的影响,为今后的选育工作提供生理生化指标。材料与方法 1.材料:采用本实验室采... 详细信息

草菇菌丝体经CO605,000仑琴辐射后,其后代子实体发现明显变化,主要表现在子实体形状和颜色上的变化,试图通过测定多酚氧化酶活性的变化,了解辐射对草菇代谢的影响,为今后的选育工作提供生理生化指标。材料与方法 1.材料:采用本实验室采集的野生草菇菌株和三明真菌研究所提供的V85菌株,接种三天后经CO605,000仑琴辐射处理,于稻草料床上栽培,七天后取旦期子实体为供试材料。 2.方法:取子实体若干于冰浴中研磨,加入适量0.1MpH7.2磷酸缓冲液,4000rpm离心10分钟,上清液为测定之酶液,溶液浓

关键词： straw mushroom radiated polyphenol oxidase.

Strain Energy Release from the 2011 9.0 Mw Tōhoku Earthquake, Japan

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Open Journal of Earthquake Research 2013年第4期2卷 75-83页

作者： Kenneth M. Cruikshank Curt D. Peterson Department of Geology Portland State University Portland USA

The purpose of this paper is to compare the strain energy released due to elastic rebound of the crust from the tragic 2011 9.0 MwTōhoku earthquake in Japan with the observed radiated seismic energy. The strain energy was calculated by analyzing coseismic displacements of 1024 GPS stations of the Japanese GEONET network. The value of energy released from the analysis is 1.75 × 1017J, which is of the same order of magnitude as the USGS-observed radiated seismic energy of 1.9 × 1017Nm (J). The strain energy method is independent of seismic methods for determining the energy released during a large earthquake. The analysis shows that although the energy release is concentrated in the epicentral region, about 12% of the total energy was released throughout the Japanese islands at distances greater than 500 km west of the epicenter. Our results also show that outside the epicentral region, the strainenergy was concentrated along known tectonic zones throughout Japan.

关键词： Japan Earthquake Crustal Strain GPS radiated Energy