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Volumetric imaging of flame refractive index, density, and temperature using background-oriented Schlieren tomography

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Science China(Technological Sciences) 2021年第1期64卷 98-110页

作者： LIU HeCong huang jianqing LI Lei CAI WeiWei School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Volumetric imaging represents one of the major development trends of flow diagnostics due to both the advancement in hardware and the requirement for more information to further understand complicated turbulent and/or reactive flows. Backgroundoriented Schlieren tomography(BOST) has become increasingly popular due to its experimental simplicity. It has been demonstrated to be capable of simultaneously recovering the distributions of refractive index, density, and temperature of ***, its capability in thermometry has only been demonstrated under the axisymmetric assumption, which greatly limits its applicability. In this work, we dedicated to developing a cost-effective BOST system for the simultaneous retrieval of refractive index, density, and temperature distributions for the asymmetric flame. A few representative tomographic inversion algorithms were assessed as well. Both numerical and experimental demonstrations were conducted and the results show that our implemented BOST can successfully reconstruct the three-dimensional temperature distribution with a satisfactory accuracy.

关键词： Schlieren tomography combustion diagnostics temperature

Graphene-Based Active Tunable Metasurfaces for Dynamic Terahertz Absorption and Polarization Conversion

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Journal of Renewable Materials 2023年第2期11卷 731-743页

作者： Haoran Wei Tian Ji jianqing huang College of Applied Science and Technology Hainan UniversityDanzhou571737China

Simultaneous broadband absorption and polarization conversion are crucial in many practical applications,especially in terahertz ***,actively tunable metamaterial systems can exploit the graphene-based nanomaterials derived from renewable resources because of the flexible surface conductivity and selective permeability of the nanomaterials at terahertz *** this paper,we propose a graphene-based active tunable bifunctional metasurface for dynamic terahertz absorption and polarization *** graphene ring presents a certain opening angle(A)along the diagonal of the xoy *** A=0°,the proposed metasurface behaves as a broadband *** results show the feasibility of achieving this polarization-insensitive absorber with nearly 100%absorptance,and the bandwidth of its 90%absorptance is 1.22 THz under normal ***,when A=40°after optimization,the proposed metasurface serves as a broadband polarization convertor,resulting in robust broadband polarization conversion ratio(PCR)curves with a bandwidth surpassing 0.5 THz in the reflection *** tune the PCR response or the broad absorption spectrum of graphene,we change the Fermi energy of graphene dynamically from 0 to 0.9 ***,both the broadband absorption and the linear polarization conversion spectra of the proposed metasurface exhibit insensitivity to the incident angle,allowing large incident angles within 40°under high-performance operating *** demonstrate the physical process,we present the impedance matching theory and measure electric field *** architecture in the THz frequency range has several applications,such as in modulators,sensors,stealth,and optoelectronic *** wave polarization and beam steering also have broad application prospects in the field of intelligent systems.

关键词： Metasurface broadband absorption polarization conversion bi-functional renewable resources

A Novel Image Digital Rights Management Scheme with High-Level Security,Usage Control and Traceability

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Chinese Journal of Electronics 2016年第3期25卷 481-494页

作者： MA Zhaofeng huang jianqing JIANG Ming NIU Xinxin Information Security Center of Beijing University of Posts and Telecommunications Library of Beijing University of Posts and Telecommunications Audio and Video Department the Third Research Institute of China Electronics Technology Group Corporation

Current methods of image protection based on chaos encryption can only provide security in Human visual system(HVS) level, however they can not provide usage control when the image is opened, printed or exported. To solve this problem, we proposed a novel image digital rights management scheme for Confidential image data security based on encryption and watermark(CIDSEW) with high-level security, usage control and traceability, in which we employed full content image encryption for confidentiality of the image to be protected, and we firstly proposed strict and detailed Usage control(UC) scheme for Confidential image data(CIData) usage password-based authentication, opening times, printing and exporting control. And when the CIData need to delivery or export to other users or domain, we proposed the secure export and misused tracing and detect approach, in which before the ciphered CIData is exported, we decrypted the CIData in a plain mode, and simultaneously we embedded user-identity-related and hardware-related information as robust watermark for traceability and responsibility confirmation. Finally, we evaluated the proposed CIDSEW by groups of variant size image data for security and efficiency,a large amount of groups of experiments manifest the proposed CIDSEW is secure, efficient, pervasive and robust for confident image data protection, usage control and misuse tracing.

关键词： Digital rights management Confidential image data security Encryption Watermark Usage control(UC) Traceability

A Video Watermarking DRM Method Based on H.264 Compressed Domain with Low Bit-Rate Increasement

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Chinese Journal of Electronics 2016年第4期25卷 641-647页

It gets more and more important for video copyright protection,it is necessary to provide efficient H.264 compression domain watermarking for video Digital rights management(DRM).A new watermarking method based on H.264 compressed domain is proposed for video DRM,in which the embedding and extracting procedure are performed using the syntactic elements of the compressed bit *** this way,complete decoding is unnecessary in both embedding and extracting *** on the analysis of the time and space,some appropriate sub-blocks are selected for embedding watermarks,increasing watermark robustness while reducing the declination of the visual *** order to avoid bit-rate increasing and strengthen the security of the proposed video watermarking scheme,only a set of nonzero coefficients quantized in different parts of macroblocks is chosen for inserting *** experiment results show the proposed scheme can achieve excellent robustness against some common attacks,the proposed scheme is secure and efficient for video content DRM protection.

关键词： Video watermarking H.264 Temporal quality Compressed domain watermarking

Li-ion battery temperature estimation based on recurrent neural networks

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Science China(Technological Sciences) 2021年第6期64卷 1335-1344页

作者： JIANG YuHeng YU YiFei huang jianqing CAI WeiWei MARCO James Key Laboratory of Education Ministry for Power Machinery and Engineering School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China University of Warwick-Warwick Manufacturing Group(WMG) Coventry CV47ALUK

The monitoring of Li-ion battery temperatures is essential to ensure high efficiency and *** this work,two types of recurrent neural networks (RNNs),which are long short-term memory-RNN (LSTM-RNN) and gated recurrent unit-RNN(GRU-RNN),are proposed to estimate the surface temperature of 18650 Li-ion batteries during the discharging processes under different ambient *** datasets acquired from the Prognostics Center of Excellence (PCo E) of NASA are used to train,validate and test the *** previous work,temperature has been set as the output of the networks;however,here the temperature difference along the time axis is adopted as the *** net heat generated results in net temperature change,which is more closely aligned with electrochemical and thermodynamic *** simulation results show that the two RNNs can achieve accurate real-time battery temperature *** maximum absolute error in temperature estimation is approximately 0.75°C and the correlation coefficient between the estimated and measured temperature curves is greater than *** influences of three crucial parameters,which are the number of hidden neurons,initial learning rate and maximum number of iterations,are also assessed in terms of training time,root mean square error and mean absolute error.

关键词： battery temperature estimation model recurrent neural network long short-term memory gated recurrent unit

健康教育结合心理护理在老年上腹部磁共振成像(MRI)增强扫描检查中的应用价值

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生命科学仪器 2024年第2期22卷 207-209页

作者：积累王丽黄淑程黄建清中国人民解放军南部战区海军第一医院放射科广东湛江524005 中国人民解放军南部战区海军第一医院体检科广东湛江524005 中国人民解放军南部战区海军第一医院妇产科广东湛江524005

目的探究健康教育结合心理护理在老年上腹部磁共振成像(MRI)增强扫描检查中的应用价值。方法选择2020年2月至2024年2月在本院就诊的160例老年上腹部MRI增强扫描检查患者,随机分为两组,各80例。对照组采用常规护理,实验组在此基础上采用... 详细信息

目的探究健康教育结合心理护理在老年上腹部磁共振成像(MRI)增强扫描检查中的应用价值。方法选择2020年2月至2024年2月在本院就诊的160例老年上腹部MRI增强扫描检查患者,随机分为两组,各80例。对照组采用常规护理,实验组在此基础上采用健康教育结合心理护理。对比两组情绪状态、护理质量、护理满意度、检查依从性及护理不良事件发生率。结果两组干预前焦虑、抑郁、人际关系敏感度、恐惧情绪评分对比,P>0.05;实验组干预后以上评分均低于对照组,P0.05;实验组干预后五项评分均高于对照组,P<0.05。实验组护理满意度(97.50%)高于对照组(87.50%),P<0.05。实验组检查依从度(96.25%)高于对照组(87.50%),P<0.05。实验组护理不良事件发生率(3.75%)低于对照组(13.75%),P<0.05。结论健康教育结合心理护理在老年上腹部MRI增强扫描检查中具有显著的护理效果,可改善患者情绪状态,提供护理质量、护理满意度与检查依从度,减少护理不良事件发生。

关键词：健康教育心理护理上腹部MRI 增强扫描

Observed levels and trends of gaseous SO_2 and HNO_3 at ***,China:Results from 1997 to 2009

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Journal of Environmental Sciences 2013年第4期25卷 726-734页

作者： Weili Lin Xiaobin Xu Xiaolan Yu Xiaochun Zhang jianqing huang Centre for Atmosphere Watch and Services Meteorological Observation CentreChina Meteorological Administration Key Laboratory for Atmospheric Chemistry Chinese Academy of Meteorological Sciences Waliguan Observatory

Long-term measurements of SO2 and HNO3, particularly those from the background sites, are rarely reported. We present for the first time the long-term measurements of SO2 and HNO3 at Waliguan （WLG）, the only global baseline station in the back-land of the Eurasian Continent. The concentrations of SO2 and HNO3 were observed at WLG from 1997 to 2009. The observed annual mean concentrations of SO2 and HNO3 at WLG were 1.28 ± 0.41 and 0.22 ± 0.19 μg/m3, respectively. The HNO3 concentrations were much higher in warmer seasons than in colder seasons, while the SO2 concentrations showed a nearly reversed seasonal pattern. In most months, the concentration of HNO3 was significantly correlated with that of SO2, suggesting that some common factors influence the variations of both gases and the precursors of HNO3 may partially be from the SO2-emitting sources. The SO2 concentration had a very significant （P 〈 0.0001） decreasing trend （-0.2 μg/（***）） in 1997-2002, but a significant （P 〈 0.05） increasing trend （＋0.06 μg/（m3-yr）） in 2003-2009. The HNO3 concentration showed no statistically significant trend during 1997-2009. While the decrease of SO2 in 1997-2002 agrees with the trend of global SO2 emissions, the increase in 2003-2009 is not consistent with the decreasing trends in many other regions over the world. Trajectory analysis suggests that the airmasses from the northern Qinghai-Tibetan Plateau and the Takla Makan Desert regions contributed significantly to the increasing trends of SO2 and HNO3 at WLG in 2003-2009, with a rate of ＋0.13 μg/（***） and ＋0.007μg/（***）, respectively.

关键词： SO2 HNO3 long-term trends Waliguan global baseline

利拉鲁肽在老年2型糖尿病治疗中对患者血糖波动、血脂以及血管内皮功能指标影响的研究

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糖尿病新世界 2024年第2期27卷 24-27页

作者：童艳陈日江陈阳黄建青福建医科大学附属龙岩第一医院内分泌科福建龙岩364000

目的探究老年2型糖尿病患者应用利拉鲁肽的治疗效果。方法选取2021年1月—2022年12月福建医科大学附属龙岩第一医院收治的52例老年2型糖尿病患者为研究对象,按照治疗方法分为两组,各26例,对照组采用二甲双胍治疗,观察组采用利拉鲁肽治... 详细信息

目的探究老年2型糖尿病患者应用利拉鲁肽的治疗效果。方法选取2021年1月—2022年12月福建医科大学附属龙岩第一医院收治的52例老年2型糖尿病患者为研究对象,按照治疗方法分为两组,各26例,对照组采用二甲双胍治疗,观察组采用利拉鲁肽治疗,对比两组血糖波动情况、血脂情况以及血管内皮功能变化状况。结果治疗后,两组患者各项血糖、血脂、内皮素-1水平均降低,且与对照组相比,观察组下降幅度更大,差异有统计学意义(P均<0.05);两组患者血清一氧化氮、血流介导的内皮血管舒张功能指标水平均升高,且与对照组相比,观察组上升幅度更大,差异有统计学意义(P均<0.05)。结论老年2型糖尿病患者应用利拉鲁肽治疗可改善其血糖、血脂以及血管内皮功能,具有理想效果。

关键词： 2型糖尿病利拉鲁肽血糖血脂血管内皮功能

针对性护理干预对多囊卵巢综合征患者体质量和代谢的影响

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实用妇科内分泌电子杂志 2024年第6期11卷 102-104页

作者：吴燕娟陈贵娥周慧萍黄建清南部战区海军第一医院呼吸内科广东湛江524000 南部战区海军第一医院药剂科广东湛江524000 南部战区海军第一医院妇产科广东湛江524000

目的探究多囊卵巢综合征患者接受针对性护理干预对其体质量及代谢的影响。方法选取多囊卵巢综合征患者120例为研究对象,随机分为对照组及观察组,每组60例。对照组采用常规护理干预,观察组采用针对性护理干预。比较两组患者的体质量及代... 详细信息

目的探究多囊卵巢综合征患者接受针对性护理干预对其体质量及代谢的影响。方法选取多囊卵巢综合征患者120例为研究对象,随机分为对照组及观察组,每组60例。对照组采用常规护理干预,观察组采用针对性护理干预。比较两组患者的体质量及代谢水平。结果护理干预后,观察组体质量、体质量指数、腰围/臀围均低于对照组(P<0.05)。观察组妊娠期糖尿病发生率为1.67%,低于对照组的11.67%,剖宫产率、新生儿低血糖发生率、早产率、转新生儿重症监护室率均低于对照组(P<0.05)。结论多囊卵巢综合征患者接受针对性护理干预,可有效改善身体状况,妊娠结局及围产儿结局均更好,值得临床推广使用。

关键词：针对性护理干预多囊卵巢综合征体质量代谢影响