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The influence of vessel attitude on spatial-temporal correlation of sea-bottom reverberation

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Chinese Journal of Acoustics 2018年第2期37卷 146-157页

作者： YAN Shanyong QIU Wei zhao erliang WANG Changhong Ocean Acoustic Technology Center Institute of Acoustics CAS 100190 Beijing University of Chinese Academy of Sciences 100049 Beijing Beijing Engineering Technology Research Center of Ocean Acoustic Equipment 100190 Beijing

The influence of vessel attitude on spatial-temporal correlation of sea-bottom re- verberation is discussed. The theoretical correlation function is deduced in consideration of the attitude of vessel. The relationship of the spatial-temporal correlation and the vessel attitude is obtained： The greater the sway of the vessel on some direction is, the faster the correlation coefficient decreases on the direction. The theoretical correlation function agrees well with the simulation result when sea-bottom has no large-scale relief but has isotropic roughness. The actual sea-bottom usually has large-scale relief and anisotropic roughness, so the vessel attitude and the large-scale relief cannot determine the shape of the correlation function, but trial data has proved their combined influence. In addition, the influence of the vessel attitude on the measurement of vertical velocity is discussed.

关键词： The influence of vessel attitude on spatial-temporal correlation of sea-bottom reverberation

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载体姿态对海底混响时空相关特性的影响

声学学报 2018年第5期43卷 745-752页

作者：闫善勇邱薇赵二亮王长红中国科学院声学研究所海洋声学技术中心北京100190 中国科学院大学北京100049 北京市海洋声学装备工程技术研究中心北京100190

讨论了载体姿态对海底混响时空相关特性的影响.考虑载体姿态对相关声呐信号发射的影响,推导理论时空相关函数,得到了时空相关特性与载体姿态之间的关系：载体在某一方向上的摇动越大,在该方向上的相关系数下降越快.将理论推导与仿真结... 详细信息

讨论了载体姿态对海底混响时空相关特性的影响.考虑载体姿态对相关声呐信号发射的影响,推导理论时空相关函数,得到了时空相关特性与载体姿态之间的关系：载体在某一方向上的摇动越大,在该方向上的相关系数下降越快.将理论推导与仿真结果进行比较,发现在海底不存在大尺度起伏、表面粗糙度各向同性的情况下,二者的时空相关函数吻合得较好。实际海底通常具有大尺度起伏和各向异性的粗糙度,时空相关函数的形状不能由载体姿态和海底大尺度起伏完全确定,但海试数据证明了二者的联合影响。此外,讨论了载体姿态对载体垂向速度测量的影响。

关键词：载体姿态海底混响相关特性时空表面粗糙度相关函数大尺度信号发射

海底密度梯度对底回波信号空间相关特性的影响研究

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声学学报 2015年第2期40卷 198-206页

作者：李丹丹王长红赵二亮邱薇中国科学院声学研究所北京100190 中国科学院大学北京100049

研究了海底表层沉积物的垂直密度梯度对底回波空间相关特性强度的影响。底回波散射截面与空间相关特性间的关系为:随入射角的增大,回波散射截面下降得越快,底回波空间相关特性越强。因此,将密度-深度模型引入海底高频回波模型进行回波仿... 详细信息

研究了海底表层沉积物的垂直密度梯度对底回波空间相关特性强度的影响。底回波散射截面与空间相关特性间的关系为:随入射角的增大,回波散射截面下降得越快,底回波空间相关特性越强。因此,将密度-深度模型引入海底高频回波模型进行回波仿真,计算回波的空间相关函数,通过分析密度梯度对底回波散射截面大小的影响,考察其对底回波空间相关特性强度的影响。从仿真分析结果可以看出,海底表层沉积物密度梯度对空间相关特性的影响较为显著,随着密度梯度的增大,回波散射截面变大且随入射角的增大下降趋势变快,空间相关半径变长,空间相关特性变强。

关键词：密度梯度回波数据散射截面空间相关信号空间相关函数表层沉积物模型引入体积散射表面反射

地理标志商标的商业价值及其侵权认定标准研究

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中国商论 2023年第7期 124-126页

作者：赵尔良中国计量大学法学院浙江杭州310000

地理标志作为一项新兴的知识产权客体,代表着得天独厚的地理可信的经济价值,2021年9月中共中央、国务院印发了《知识产权强国建设纲要(2021—2035年)》,也意味着未来地理标志在经济方面和社会方面发挥的商业价值愈发重要。地理标志商标... 详细信息

地理标志作为一项新兴的知识产权客体,代表着得天独厚的地理可信的经济价值,2021年9月中共中央、国务院印发了《知识产权强国建设纲要(2021—2035年)》,也意味着未来地理标志在经济方面和社会方面发挥的商业价值愈发重要。地理标志商标最主要的商业价值有三方面:品牌信誉价值、贷款融资价值、法律优先保护价值。地理标志证明商标的侵权认定标准仍以“混淆理论”为基础,但是对侵权认定的范围需要扩展到对地理标志产品的产地和品质的误认,在判断是否合理使用地理标志证明商标时,需要综合考虑地理标志的特殊性、产品的品质、使用方式和主观意图。

关键词：地理标志证明商标商业价值侵权认定混淆合理使用

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Recycling arsenic-containing bio-leaching residue after thermal treatment in cemented paste backfill:Structure modification,binder properties and environmental assessment

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2136-2147页

作者： Dengfeng zhao Shiyu Zhang Yingliang zhao Department of Mining Engineering Lyuliang UniversityLvliang 033000China School of Civil and Environmental Engineering University of Science and Technology BeijingBeijing 100083China School of Mining Engineering Taiyuan University of TechnologyTaiyuan 030024China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong 00852China

The substantial arsenic(As)content present in arsenic-containing bio-leaching residue(ABR)presents noteworthy environ-mental challenges attributable to its inherent instability and susceptibility to *** its elevated calcium sulfate content,ABR exhibits considerable promise for industrial *** study delved into the feasibility of utilizing ABR as a source of sulfates for producing super sulfated cement(SSC),offering an innovative binder for cemented paste backfill(CPB).Thermal treatment at varying temperatures of 150,350,600,and 800℃ was employed to modify ABR’s *** investigation encompassed the examination of phase transformations and alterations in the chemical composition of As within ***,the hydration characteristics of SSC utilizing ABR,with or without thermal treatment,were studied,encompassing reaction kinetics,setting time,strength development,and *** findings revealed that thermal treatment changed the calcium sulfate structure in ABR,consequently impacting the resultant sample ***,calcination at 600℃ demonstrated optimal modification effects on both early and long-term strength *** enhanced performance can be attributed to the augmented formation of reaction products and a densified ***,the thermal treatment elicited modifications in the chemical As fractions within ABR,with limited impact on the As immobilization capacity of the prepared binders.

关键词： cemented paste backfill bio-leaching residue arsenic immobilization binder hydration calcination

Automatic modeling algorithm of stochastic error for inertial sensors

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Control Theory and Technology 2024年第1期22卷 81-91页

作者： Luodi zhao Long zhao School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191China Digital Navigation Center Beihang UniversityBeijing100191China Science and Technology on Aircraft Control Laboratory Beihang UniversityBeijing100191China

This paper proposes an automatic algorithm to determine the properties of stochastic processes and their parameters for inertial error. The proposed approach is based on a recently developed method called the generalized method of wavelet moments (GMWM), whose estimator was proven to be consistent and asymptotically normally distributed. This algorithm is suitable mainly (but not only) for the combination of several stochastic processes, where the model identification and parameter estimation are quite difficult for the traditional methods, such as the Allan variance and the power spectral density analysis. This algorithm further explores the complete stochastic error models and the candidate model ranking criterion to realize automatic model identification and determination. The best model is selected by making the trade-off between the model accuracy and the model complexity. The validation of this approach is verified by practical examples of model selection for MEMS-IMUs (micro-electro-mechanical system inertial measurement units) in varying dynamic conditions.

关键词： GMWM Stochastic process Inertial sensor Sensor calibration Error model Allan variance

Meeting the challenges of invasive alien species

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National Science Review 2024年第3期11卷 296-298页

作者： Weijie zhao NSR news

The Xinjiang Uygur Autonomous Region of China is famous for its tomato production. Abundant sunshine, large day–night temperature difference and the abundant irrigation by snowmelt from the Tianshan Mountains produce...

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Ling-Ling Chen: RNA has its own features;don't study it as a protein

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National Science Review 2024年第2期11卷 301-305页

作者： Weijie zhao NSR

Non-coding RNA(ncRNA) has been a very active research area over the past 30 years. From small nc RNA – the discovery of RNA interference won the lead researchers the Nobel Prize, to long ncRNA(lncRNA), which has attracted much attention in recent years, various nc RNAs participate in all kinds of biological processes and show a variety of biomedical application prospects.

关键词： RNA

Giant Flexoelectric Effect in Snapping Surfaces Enhanced by Graded Stiffness

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Acta Mechanica Solida Sinica 2024年第4期37卷 528-540页

作者： Chuo zhao Department of Aeronautics Imperial College LondonSouth Kensington CampusLondonSW72AZUK

Flexoelectricity is present in nonuniformly deformed dielectric materials and has size-dependent properties, making it useful for microelectromechanical systems. Flexoelectricity is small compared to piezoelectricity;therefore, producing a large-scale flexoelectric effect is of great interest. In this paper, we explore a way to enhance the flexoelectric effect by utilizing the snap-through instability and a stiffness gradient present along the length of a curved dielectric plate. To analyze the effect of stiffness profiles on the plate, we employ numerical parameter continuation. Our analysis reveals a nonlinear relationship between the effective electromechanical coupling coefficient and the gradient of Young’s modulus. Moreover, we demonstrate that the quadratic profile is more advantageous than the linear profile. For a dielectric plate with a quadratic profile and a modulus gradient of − 0.9, the effective coefficient can reach as high as 15.74 pC/N, which is over three times the conventional coupling coefficient of piezoelectric material. This paper contributes to our understanding of the amplification of flexoelectric effects by harnessing snapping surfaces and stiffness gradient design.

关键词： Functionally graded material Flexoelectricity Numerical continuation Snap-through instability