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长江口拦门沙河段航道回淤的波浪动力环境Ⅱ:洪枯季作用差异 被引量:3
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作者 刘猛 《水运工程》 北大核心 2016年第6期110-115,共6页
开展了长江口拦门沙河段波浪对河床作用的洪枯季差异及规律研究,结果表明:1)长江口拦门沙河段波能随周期的分布曲线在洪季表现为“窄峰”特征,波能主要集中在4.0~7.0 s,而洪季表现为“宽峰”或“双峰”特征,波能主要集中在4.0~12.0 s;... 开展了长江口拦门沙河段波浪对河床作用的洪枯季差异及规律研究,结果表明:1)长江口拦门沙河段波能随周期的分布曲线在洪季表现为“窄峰”特征,波能主要集中在4.0~7.0 s,而洪季表现为“宽峰”或“双峰”特征,波能主要集中在4.0~12.0 s;2)与枯季相比,洪季长周期的高能波发生频率及其波能所占年总波能的比例显著提高,其中波能增加数十倍;3)长江口拦门沙区域的波浪按周期可分为3种类型,即低能波、高能波以及过渡波,其中低能波对拦门沙区域的深水河床基本无作用,高能波对拦门沙区域的深水河床作用非常显著,但过渡波对拦门沙区域的深水河床作用不确定,视波向变化而定。 展开更多
关键词 长江口拦门沙 航道 洪枯季差异 最大循环动水压差 高能 低能波 过渡
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Novel Zero-Watermarking Scheme Based on DWT-DCT 被引量:3
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作者 Yu Yang Min Lei +2 位作者 Xiaoming Liu Zhiguo Qu Cheng Wang 《China Communications》 SCIE CSCD 2016年第7期122-126,共5页
Essential characteristics for watermark registration and detection without data modification can be used in anaudio zero-watermarking scheme.In this paper,a novel audio zero-watermarking scheme based on discrete wavel... Essential characteristics for watermark registration and detection without data modification can be used in anaudio zero-watermarking scheme.In this paper,a novel audio zero-watermarking scheme based on discrete wavelet transform(DWT) and discrete cosine transform(DCT) is presented.Thewatermark is registered by comparing the mean absolute values of the adjacent frame coefficients after DWT and DCT.Simulation results show that the proposed scheme is stronglyrobusttocommon attacks such as AWGN,downsampling,low-pass filtering,requantization,and MP3 compression.A performance analysis of the proposed scheme shows that all bit error rates after attacks are zero. 展开更多
关键词 zero-watermark discrete wavelets transform discrete cosine transform
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Antiproton-Nucleus Interaction and Coulomb Effect at High Energies
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作者 ZHOULi-Juan WUQing +3 位作者 GUYun-Ting MAWei-Xing TANZhen-Qiang HUZhao-Hui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4期699-703,共5页
The Coulomb effect in high energy antiproton-nucleus elastic and inelastic scattering from 12C and 16O is studied in the framework of Glauber multiple scattering theory for five kinetic energies ranged from 0.23 to 1.... The Coulomb effect in high energy antiproton-nucleus elastic and inelastic scattering from 12C and 16O is studied in the framework of Glauber multiple scattering theory for five kinetic energies ranged from 0.23 to 1.83 GeV.A microscopic shell-model nuclear wave functions, Woods-Saxon single-particle wave functions, and experimental pN amplitudes are used in the calculations. The results show that the Coulomb effect is of paramount importance for filling up the dips of differential cross sections. We claim that the present result for inelastic scattering of antiproton-12C is sufficiently reliable to be a guide for measurements in the very near future. We also believe that antiproton nucleus elastic and inelastic scattering may produce new information on both the nuclear structure and the antinucleon-nucleon interaction, in particular the p-neutron interaction. 展开更多
关键词 p-nucleus scattering glauber scattering theory nuclear wave functions
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High Voltage Pulse Power and the Technics for the Capacitor Power-Storage Type
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作者 KANG Zihua WANG Mingwei QIAN Jiamei RAO Jun LI Xiujuan ZHENG Tieliu WANG Xuehua 《Southwestern Institute of Physics Annual Report》 2004年第1期73-76,共4页
Lower hybrid wave (LHW), electro cyclotron (EC) and neutral beam injection (NBI) etc. are the important methods of auxiliary heating. They would be devoted to the HL-2A tokamak step by step. In order to satisfy ... Lower hybrid wave (LHW), electro cyclotron (EC) and neutral beam injection (NBI) etc. are the important methods of auxiliary heating. They would be devoted to the HL-2A tokamak step by step. In order to satisfy the debug of each system and the need of the experiment, the system should be equipped with high voltage pulse power (HVPP) according to the requirement. 展开更多
关键词 Capacitor power-storage High voltage pulse power
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Hydration and Mechanical Properties of Portland Cement Blended with Low-CaO Steel Slag
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作者 Eugene Atiemo Kwabena Appiah Boakye James Sarfo-Ansah 《Journal of Physical Science and Application》 2014年第7期444-449,共6页
The hydration and mechanical properties of Portland cement blended with low-CaO steel slag were studied and reported. The steel slag was used to replace cement up to 30% and then blended cement powder, paste and morta... The hydration and mechanical properties of Portland cement blended with low-CaO steel slag were studied and reported. The steel slag was used to replace cement up to 30% and then blended cement powder, paste and mortar samples prepared for the experiment. The quantitative analysis of XRD shows that ettringite formation is greatly reduced by incorporation of steel slag but there was a relatively low reduction of portlandite. Thermal analysis by TG shows that slag injection reduced portlandite content in the cement by at least 50%. Generally, the slag cement pastes required less water to form a workable paste compared to the reference cement, reducing as the slag content was increased. However, the setting times were higher than the reference. The permeability of the blended cement samples were lower than the control. The incorporation of 5% slag could not have an effect on the compressive strength of the concrete. The results confirmed that whilst cements with up to 15% slag content satisfied the strength requirements of class 42.5 N and those containing 20%-30% produce Class 32.5R cement. 展开更多
关键词 HYDRATION cement low-CaO steel slag ETTRINGITE portlandite permeability.
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Ultralow frequency wave characteristics extracted from particle data:Application of IGSO observations 被引量:6
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作者 LI Li ZHOU XuZhi +5 位作者 ZONG QiuGang CHEN XingRan ZOU Hong REN Jie HAO YiXin ZHANG XianGuo 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2017年第3期419-424,共6页
3 Summary and discussion In the generalized drift resonance theory[17],a characteristic signature of the ULF wave-particle interactions is the increasingly-tilted stripes in the particle energy spectrum.The phase diff... 3 Summary and discussion In the generalized drift resonance theory[17],a characteristic signature of the ULF wave-particle interactions is the increasingly-tilted stripes in the particle energy spectrum.The phase difference across different energy channels is relatively small 展开更多
关键词 ultralow frequency waves wave-particle interactions drift resonance ULF wave characteristics
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