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An uncertainty investigation for liner impedance eduction methods

Chinese Journal of Aeronautics 2024年第3期37卷 49-59页

作者： Weihao SHI xiaodong jing School of Energy and Power Engineering Beihang UniversityBeijing 100191China

Impedance eduction methods have been developed for decades to meet the increasing need for high-quality impedance data in the design and optimization of acoustic liners.To this end,it is important to fully investigate the uncertainty problem,to which only limited attention has been devoted so far.This paper considers the possibility of acoustically-induced structural vibration as a nonnegligible uncertainty or error source in impedance eduction experiments.As the frequency moves away from the resonant frequency,with the increase in the value of cavity reactance,the acoustic particle velocity inside liner orifices possibly decreases to the extent comparable to the vibration velocity of liner facing sheet.Thus,the acoustically-induced vibration,although generally being weak except at the inherent structural frequencies,may considerably affect the impedance eduction results near the anti-resonant frequency where the liner has poor absorption.To demonstrate the effect of structural vibration,the vibration velocity of liner facing sheet is estimated from the experimentally educed admittance of the liner samples whose orifices are sealed with tape.Further,a three-dimensional numerical model is set up,in which normal particle velocity is introduced over the solid portion of liner facing sheet to imitate structural vibration,rather than directly solving the acoustic-structural coupling problem.As shown by the results,the vibration of liner facing sheet,whose velocity is as small as estimated by the experiment,can result in anomalous deviation of the educed impedance from the impedance model near the anti-resonant frequency.The trend that the anomalous deviation varies with frequency is numerically captured.

关键词： Impedance eduction Uncertainty analysis Acoustically-induced structural vibration Anti-resonant frequency Perforated liner

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The Discourse-Historical Approach of Identity Construction in Corporate Promotional Videos for External Publicity Image

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Proceedings of Business and Economic Studies 2024年第2期7卷 178-183页

作者： xiaodong Wang jing Yu Northeast Agricultural University Harbin 150001Heilongjiang ProvinceChina Zhuanghe Dexian School Dalian 116499Liaoning ProvinceChina

Corporate identity construction of external publicity image is an important part of the development of enterprises.Based on Wodak’s discourse-historical approach,this study takes the text of COFCO’s English promotional video as the research object,analyzes the corporate brand image,media image,organizational image,and environmental image constructed by the enterprises from three steps:linguistic expression,discourse strategy,and theme to provide references for Chinese enterprises to enhance their international influence.

关键词： Corporate promotional videos External publicity image Discourse-historical approach

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Hierarchical Fe_(x)Bi_(2−x)S_(3) solid solutions for boosted supercapacitor performance

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Nano Research 2024年第5期17卷 3997-4005页

作者： Fengming Zhou xiaodong Wang Ruijie jing Xiaoyu Li Qi Zhang Zhenjiang Li Yunmei Du Zhenyu Xiao Lei Wang International Cooperation United Laboratory of Eco-chemical Engineering and Green Manufacturing College of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China Technology Innovation Center of Battery Safety and Energy Storage Technology QingdaoInternational Science and Technology Cooperation Base of QingdaoCollege of Environment and Safety EngineeringQingdao University of Science and TechnologyQingdao 266042China

For the pursuit of high energy supercapacitors,the development of high performance pseudocapacitance or battery-type negative electrode material is urgently needed to make up for the capacity shortage of commercial electric double layer capacitor(EDLC)type materials.Herein,a porous and defect-rich Fe_(x)Bi_(2-x)S_(3) solid solution structure is firstly constructed by employing Fe-doped Bi_(2)O_(2)CO_(3) porous nanosheets as a precursor,which presents dramatically increased energy storage performance than Bi_(2)S_(3) and FeS_(2) phase.For the optimized Fe_(x)Bi_(2-x)S_(3) solid solution(FeBiS-60%),the Fe solute is free and random dispersed in Bi_(2)S_(3) framework,which can effectively modulate the electronic structure of Bi element and introduce rich-defect due to the existence of Fe(II).Meanwhile,the FeBiS-60%,constructed by pore nanosheets that are assembled by self-supported basic nanorod units,presents rich mesoporous channels for fast mass transfer and abundant active sites for promoting capacity performance.Therefore,a high capacitance of 832.8 F·g^(-1) at a current density of 1 A·g^(-1) is achieved by the FeBiS-60%electrode.Furthermore,a fabricated Ni3S_(2)@Co_(3)S_(4)(NCS)//FeBiS-60%hybrid supercapacitor device delivers an outstanding energy density of 85.33 Wh·kg^(-1) at the power density of 0.799 kW·kg^(-1),and ultra-long lifespan of remaining 86.7%initial capacitance after 8700 cycles.

关键词： supercapacitor solid solutions defect structure hierarchical structure Bi_(2)S_(3)

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MEIC-global-CO_(2):A new global CO_(2)emission inventory with highly-resolved source category and sub-country information

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Science China Earth Sciences 2024年第2期67卷 450-465页

作者： Ruochong XU Dan TONG Qingyang XIAO Xinying QIN Cuihong CHEN Liu YAN jing CHENG Can CUI Hanwen HU Wenyu LIU Xizhe YAN Huaxuan WANG xiaodong LIU Guannan GENG Yu LEI Dabo GUAN Kebin HE Qiang ZHANG Department of Earth System Science Ministry of Education Key Laboratory for Earth System ModelingInstitute for Global Change StudiesTsinghua UniversityBeijing100084China State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing100084China Chinese Academy of Environmental Planning Beijing100041China Institute for Carbon Neutrality Tsinghua UniversityBeijing100084China

CO_(2)emission inventory provides fundamental data for climate research and emission mitigation.Currently,most global CO_(2)emission inventories were developed with energy statistics from International Energy Agency(IEA)and were available at country level with limited source categories.Here,as the first step toward a high-resolution and dynamic updated global CO_(2)emission database,we developed a data-driven approach to construct seamless and highly-resolved energy consumption data cubes for 208 countries/territories,797 sub-country administrative divisions in 29 countries,42 fuel types,and 52 sectors,with the fusion of activity data from 24 international statistics and 65 regional/local statistics.Global CO_(2)emissions from fossil fuel combustion and cement production in 1970–2021 were then estimated with highly-resolved source category(1,484 of total)and sub-country information(797 of total).Specifically,73%of global CO_(2)emissions in 2021 were estimated with sub-country information,providing considerably improved spatial resolution for global CO_(2)emission accounting.With the support of detailed information,the dynamics of global CO_(2)emissions across sectors and fuel types were presented,representing the evolution of global economy and progress of climate mitigation.Remarkable differences of sectoral contribution were found across sub-country administrative divisions within a given country,revealing the uneven distribution of energy and economic structure among different regions.Our estimates were generally consistent with existing databases at aggregated level for global total or large emitters,while large discrepancies were observed for middle and small emitters.Our database,named the Multiresolution Emission Inventory model for Climate and air pollution research(MEIC)is publicly available through http://*** with highly-resolved information and timely update,which provides an independent carbon emission accounting data source for climate research.

关键词： CO_(2)emissions Data-driven approach Highly-resolved source category Sub-country information

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Temperature field simulation of polyolefin-absorber mixture by FDTD-FDM model during microwave heating

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Chinese Journal of Chemical Engineering 2020年第11期28卷 2900-2917页

作者： xiaodong jing Hao Wen Zhihong Xu State Key Laboratory of Multiphase Complex Systems Beijing Engineering Research Centre of Process Pollution ControlInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

This work has performed a numerical simulation of the temperature field during microwave heating of polyolefin-absorber mixture by means of a combined electric and thermal model.A finite difference time domain was used to model the electric field distribution within the cavity,while the finite difference method was used to calculate the temperature field distribution in different reactors.This study has focused only on the process from room temperature to 500 K for reducing heating time and energy consumption.This temperature range is a process with high energy consumption,difficult to control and great influence on the follow-up reaction.Temperature dependence of dielectric properties and thermal properties of heated materials are fully considered and simulated through an iterative process.The simulation results show that input power,the size and location of the heated materials,the position of the waveguide,and the kinds of microwave absorbers are important factors affecting the heating process.As a result,the uniform temperature distribution(the temperature difference Tdb10 K)can be achieved by choosing the appropriate input power(500–2000 W),the appropriate proportion of microwave absorber(the volume ratio of Si C to HDPE is 30:70),and combining with the moving and rotating of the heated materials.The uniform temperature field obtained without mechanical stirring is very important for reducing energy consumption and subsequent reactions.

关键词： Microwave heating Temperature field Finite difference time domain Finite difference method

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波前编码红外成像系统的温度梯度适应能力探究

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天津大学学报（自然科学与工程技术版） 2024年第5期57卷 521-529页

作者：盛婧蔡怀宇汪毅陈晓冬天津大学精密仪器与光电子工程学院天津300072

利用波前编码技术为红外光学系统进行无热化设计可提高其在不同均匀工作温度下的适应能力,但针对温度突变、成像系统内温度分布不均情况,波前编码技术是否能正常进行成像及其适用的温度范围还有待进一步研究.为简化分析流程,采用温度梯... 详细信息

利用波前编码技术为红外光学系统进行无热化设计可提高其在不同均匀工作温度下的适应能力,但针对温度突变、成像系统内温度分布不均情况,波前编码技术是否能正常进行成像及其适用的温度范围还有待进一步研究.为简化分析流程,采用温度梯度模型来仿真非稳态下的温度变化.利用温度梯度模型来定性分析光学系统在轴向、径向温度梯度为系统引入的附加像差.计算两个方向下的光程差变化来比较两种温度梯度环境下系统的成像性能差异.在此基础上,为非稳态温度环境下红外光学系统的设计建立了结合光/机/热分析的无热化设计流程,通过ZEMAX设计了一套最大轴向尺寸为85 mm、最大径向尺寸为25 mm的红外光学系统,通过SolidWorks加载轴向和径向的热形变,探究所设计的系统能够适用的温度梯度范围.结果表明,结合光/机/热分析的无热化设计流程可以有效表明系统在非稳态温度下的成像情况.对上述采用三次相位板进行无热化设计的红外光学系统,在非稳态温度下可以适应±10℃的轴向温差范围,但是仅可以适应±1℃的径向温差范围.因此在进行红外波前编码光学系统的无热化设计时,需要对径向方向进行重点优化.

关键词：波前编码技术红外光学成像系统温度梯度三次相位板

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基于双螺旋相位板的单目三维编码成像

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光学学报 2024年第9期44卷 85-100页

作者：张越蔡怀宇盛婧汪毅陈晓冬天津大学精密仪器与光电子工程学院光电信息技术教育部重点实验室

提出一种能够同时获得场景深度信息并实现景深拓展的成像方法。通过在相机的光瞳处引入双螺旋相位调制，将深度信息编码在图像中，使用端到端的深度学习技术对成像过程进行反演，最终得到景深拓展的图像和深度图。分析了相位板参数和物... 详细信息

提出一种能够同时获得场景深度信息并实现景深拓展的成像方法。通过在相机的光瞳处引入双螺旋相位调制，将深度信息编码在图像中，使用端到端的深度学习技术对成像过程进行反演，最终得到景深拓展的图像和深度图。分析了相位板参数和物距对成像性能的影响，讨论了在给定的深度范围内合理选择相位板参数的方法。在NYU Depth V2数据集的深度范围内进行了仿真，深度估计相对误差最低可达8.3%，景深拓展后图像的峰值信噪比（PSNR）和结构相似度（SSIM）最高分别可达35.254 dB和0.960，所提方法与传统光学系统相比景深可拓展数十倍以上，并且结果证明了缩小探测范围和增大物距可提升平均深度估计精度。针对闸机人脸识别等潜在的应用场景，以1.1～1.32 m为探测范围搭建了实物系统，在真实场景中深度估计的相对误差为2.2%，所提方法相比传统光学系统景深拓展约10倍。本文方法仅需在传统成像系统中加入一块相位板即可同时实现场景的深度估计和景深拓展功能，在低成本三维成像和检测领域具有一定的应用潜力。

关键词：成像系统计算成像单目深度估计景深拓展双螺旋相位板点扩散函数

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总体国家安全观视域下数据安全治理的路径选择

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中国科技论坛 2024年第2期 147-157,167页

作者：李晓东董少平吴菁燕山大学文法学院河北秦皇岛066000 中南财经政法大学湖北武汉430073

数字时代的数据安全问题已成为总体国家安全观中的重要方面,但是在数据安全治理中存在以数据主权适用的模糊性、数据安全范围的动态性、数字人权保护的多面性为核心的现实困境,以及以数据安全本位与数据自由本位之争为核心的理论困境,... 详细信息

数字时代的数据安全问题已成为总体国家安全观中的重要方面,但是在数据安全治理中存在以数据主权适用的模糊性、数据安全范围的动态性、数字人权保护的多面性为核心的现实困境,以及以数据安全本位与数据自由本位之争为核心的理论困境,因此需要寻找新的理论供给以解决上述困境。结合总体国家安全观的理论指导和数字领域的理论应变,可以形成数据安全治理的第三条路径。以总体国家安全观为基本指引,凝练出以安全实践本位、总体性治理方式和人民安全价值目标的数据安全治理基本原则。“节点论”“数据生命周期论”“协同论”在承袭基本原则的基础上,可以体系化地解决数字安全治理中“靠谁治理”“治理什么”“如何治理”的难题,最终构建数据安全治理的第三条路径。

关键词：数据安全治理总体国家安全观节点论数据生命周期论协同论

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Investigation of straightforward impedance eduction method on single-degree-of-freedom acoustic liners

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Chinese Journal of Aeronautics 2018年第12期31卷 2221-2233页

作者： Xianghai QIU Bo XIN Long WU Yang MENG xiaodong jing Fluid and Acoustic Engineering Laboratory School of Energy and Power Engineering Beihang University

In order to address the current aircraft noise problem, the knowledge of impedance of acoustic liners subjected to high-intensity sound and grazing flow is of crucial importance to the design of high-efficiency acoustic nacelles. To this end, the present study is twofold. Firstly, the StraightForward impedance eduction Method(SFM) is evaluated by the strategy that the impedance of a liner specimen is firstly experimentally educed on a flow duct using the SFM, and then its accuracy is checked by comparing the numerical prediction with the measured wall sound pressure of the flow duct. Secondly, the effects of grazing flow and high-intensity sound on the impedance behavior of two single-layer liners are investigated based on comparisons between educed impedance and predictions by three impedance models. The performance of the SFM is validated by showing that the educed impedance leads to excellent agreement between the simulation and the measured wall sound pressure for different grazing flow Mach numbers and Sound Pressure Levels(SPLs) and over a frequency range from 3000 Hz down to 500 Hz. The grazing flow effect generally has the tendency that the acoustic resistance exhibits a slight decrease before it increases linearly with an increase in Mach,predicted successfully by the sound-vortex interaction theoretical model and the Kooi semi-empirical impedance model. However, the Goodrich semi-empirical impedance model gives only a simple linear relation of acoustic resistance starting from Mach zero. Additionally, when the SPL increases from 110 to 140 d B in the present investigation, the acoustic resistance exhibits a significant increase at all frequencies in the absence of flow; however, the resistance decreases slightly under a grazing flow of Mach 0.117. It indicates that the SPL effect can be greatly inhibited when flow is present,and the grazing flow effect can be reduced partly as well at a relatively high SPL.

关键词： Acoustic liner Experimental validation Grazing flow effect High sound intensity effect Impedance eduction Numerical evaluation Straightforward impedance eduction method

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贝伐珠单抗不良事件信号挖掘和用药风险分析

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医药导报 2024年第5期43卷 814-820页

作者：孙小东王静陈力达州市中心医院药学部达州635000 四川绵阳四0四医院/绵阳市第一人民医院药学部绵阳621000 四川大学华西第二医院药学部/循证药学中心成都610066

目的挖掘贝伐珠单抗的不良事件(AE)信号,总结相关AE临床特征和用药风险,为临床安全用药提供参考。方法提取美国食品药品管理局(FDA)不良事件报告系统(FAERS)中2019年第1季度至2023年第1季度贝伐珠单抗的相关AE报告,应用比例失衡法中的... 详细信息

目的挖掘贝伐珠单抗的不良事件(AE)信号,总结相关AE临床特征和用药风险,为临床安全用药提供参考。方法提取美国食品药品管理局(FDA)不良事件报告系统(FAERS)中2019年第1季度至2023年第1季度贝伐珠单抗的相关AE报告,应用比例失衡法中的报告比值比(ROR)法和综合标准(MHRA)法对进行数据挖掘及分析。结果共收集贝伐珠单抗AE报告17831份,相应有效信号映射得到的系统器官(SOC)共24个,其中各类损伤、中毒及操作并发症占比最大(18.82%),其次为血液及淋巴系统疾病(12.14%)和各类检查(12.07%);较为常见的AE为超说明书使用(3478例)、故意导致的产品使用问题(1040例)、高血压(993例)等。关联度较大的AE主要有视网膜血管造影异常(ROR 2916.79)、软骨坏死(ROR 911.34)、喉坏死(ROR 607.73)等,且其中80%为贝伐珠单抗新的药品不良反应(ADR)。结论使用贝伐珠单抗除了关注常见的ADR外,还需关注是否可能产生新的ADR。该药超说明书使用情况较多,临床药师应严格把关其使用的规范性、合理性、安全性。

关键词：贝伐珠单抗超说明书用药安全用药

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