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Power-Domain Collision-Tolerant Random Access Method with Auxiliary Beam for Satellite Internet of Things:A New Solution

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China Communications 2024年第8期21卷 236-248页

作者： Xu Yuanyuan liu ziwei Bian Dongming Zhang Gengxin School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Institute of Communications Engineering PLA University of Science and TechnologyNanjing 210007China

There are numerous terminals in the satellite Internet of Things(IoT).To save cost and reduce power consumption,the system needs terminals to catch the characteristics of low power consumption and light *** regular random access(RA)protocols may generate large amounts of collisions,which degrade the system throughout *** near-far effect and power control technologies are not applicable in capture effect to obtain power difference,resulting in the collisions that cannot be *** fact,the optimal design at the receiving end can also realize the condition of packet power domain separation,but there are few relevant *** this paper,an auxiliary beamforming scheme is proposed for power domain signal *** adds an auxiliary reception beam based on the conventional beam,utilizing the correlation of packets in time-frequency domain between the main and auxiliary beam to complete signal *** roll-off belt of auxiliary beam is used to create the carrier-to-noise ratio(CNR)*** paper uses the genetic algorithm to optimize the auxiliary beam *** results show that the proposed scheme outperforms slotted ALOHA(SA)in terms of system throughput per-formance and without bringing terminals additional control burden.

关键词： beamforming non-orthogonal multiple access random access satellite Internet of Things

Nitric oxide removal from flue gas coupled with the Fe^(Ⅱ)EDTA regeneration by ultraviolet irradiation

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Chinese Journal of Chemical Engineering 2024年第4期68卷 133-143页

作者： Yuan Xu ziwei liu Ying Dai Jinbo Ouyang Zhuyao Li Yuling Zhu Jianhua Ding Feiqiang He School of Chemistry and Materials Science East China University of TechnologyNanchang 330013China

During wet complexation denitrification of flue gas,Fe^(Ⅱ)EDTA regeneration,also known as reducing Fe^(Ⅱ)EDTA and Fe^(Ⅱ)EDTA-nitric oxide(NO)to Fe^(Ⅱ)EDTA,is *** this paper,ultraviolet(UV)light was used for the first time to reduce Fe^(Ⅱ)*** experimental result demonstrated that Fe^(Ⅱ)EDTA-NO reduction rate increased with UV power increasing,elevated temperature,and initial Fe^(Ⅱ)EDTA-NO concentration ***^(Ⅱ)EDTA-NO reduction rate increased first and then decreased as pH value increased(2.0-10.0).Fe^(Ⅱ)EDTA-NO reduction with UV irradiation presented a first order reaction with respect to Fe^(Ⅱ)*** with other Fe^(Ⅱ)EDTA regeneration methods,Fe^(Ⅱ)EDTA regeneration with UV show more superiority through comprehensive consideration of regeneration rate and ***,NO absorption experiment by Fe^(Ⅱ)EDTA solution with UV irradiation confirmed that UV can significantly promote the NO removal performance of Fe^(Ⅱ)*** oxygen concentration(3%(vol))and acidic environment(pH=4)was favorable for NO *** UV power increasing as well as temperature decreasing,NO removal efficiency *** addition,the mechanism research indicates that NO from flue gas is mostly converted to NO_(2)-,NO_(3)-,NH_(4)^(+),N_(2),and N_(2)O with Fe^(Ⅱ)EDTA absorption liquid with UV *** strengthens NO removal in Fe^(Ⅱ)EDTA absorption liquid by forming a synergistic effect of ***,compared with NO removal methods with Fe^(Ⅱ)EDTA,Fe^(Ⅱ)EDTA combined UV system shows prominent technology advantage in terms of economy and secondary pollution.

关键词： Fe^(II)EDTA Ultraviolet Flue gas Nitric oxide Regeneration Absorption

Optimization design and experiment of the variable differential gear train planting mechanism

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 85-93页

作者： Xiong Zhao ziwei liu Yuanwu Jia Xingxiao Ma Pengfei Zhang Jianneng Chen School of Mechanical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Xi’an International University Engineering College Xi’an 710077China Hangzhou Vocational&Technical College Hangzhou 310018China

In order to improve the adaptability of the planting mechanism for different plant spacings,a variable differential gear train planting mechanism based on precise pose and trajectory control was proposed by combining the open chain 2R rod group and the variable differential gear *** to the pose requirements of receiving seedling point,transporting seedling point and planting point,three precise pose points of constrained planting trajectory were *** the three-position motion generation structural synthesis method,combined with computer-aided optimization design software,a set of mechanism parameters that meet the planting requirements were *** on the optimized mechanism parameters,by only changing the coordinates of two trajectory shape control points,three planting trajectories with key point position information adapted to 300 mm,400 mm and 500 mm plant spacing were obtained by interpolation,and three pairs of total transmission ratio of three groups of variable differential gear trains were *** distributing the total transmission ratio of the mechanism,the fixed axis gear train and the differential gear train are *** fixed axis gear train included a pair of non-circular gear pairs and a pair of positive gear pairs,which were convenient for disassembly and *** former drives the sun gear at variable speed,and the latter drives the planet carrier at uniform *** on this structure,the transmission ratio of the positive gear pair is-1,and the transmission ratio of the differential gear train is *** sub-transmission ratio of the single-stage non-circular gear pair was calculated and the pitch curves of three pairs of noncircular gears were *** pairs of non-circular gear pairs with different transmission ratios were replaced in turn and three sets of planting mechanisms were modeled in three *** virtual prototype motion simulation was completed by ADAMS software,and the p

关键词： plant spacing planting mechanism variable differential gear train precise pose trajectory control parameter optimization

Magnetic nanofluid-based liquid marble for a self-powered mechanosensation

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Droplet 2024年第3期3卷 57-64页

作者： Manhui Chen ziwei liu Yike Li Shanfei Zhang Peng Chen Pengyu Zhang Bin Su State Key Laboratory of Material Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhanChina

Magnetic nanofluid possesses the characteristic of interfering with the propagation of the magnetic field,endowing it with the sensing property in ***,the residual adhesion of magnetic nanofluid as it flows over solid surfaces remains an open *** marbles allow for quantities of liquids to be encapsulated by hydrophobic particles,ensuring a unique nonstick property for utilization in different *** this study,being capsuled by hydrophobic nano-/microscale powders,a magnetic nanofluid-based liquid marble(MNLM)with well mechanical stability has been fabricated.A magnetic nanofluid posture detector(MNPD),which consists of an MNLM,a magnetic tube,and coils,has been assembled that can convert mechanical energy to electricity as it freely rolls on the solid *** recognition can be achieved when combining five MNPDs with *** fabricated MNPD possesses a good signal recognition capability,which can separately distinguish the bending of each ***,a variety of language hand gestures with specific meanings(dig-its,letters,“OK,”and“I Love You”)can be further recognized through corresponding *** potential of MNPD in the realm of gesture recognition will offer a novel avenue for flexible wearables.

关键词： wear fluid property

Through-polymer,via technology-enabled,flexible,lightweight,and integrated devices for implantable neural probes

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Microsystems & Nanoengineering 2024年第2期10卷 279-291页

作者： Cunkai Zhou Ye Tian Gen Li Yifei Ye Lusha Gao Jiazhi Li ziwei liu Haoyang Su Yunxiao Lu Meng Li Zhitao Zhou Xiaoling Wei Lunming Qin Tiger H.Tao liuyang Sun College of Electronics and Information Engineering Shanghai University of Electric PowerShanghaiChina 2020 X-Lab Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghaiChina School of Graduate Study University of Chinese Academy of SciencesBeijingChina State Key Laboratory of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghaiChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingChina School of Physical Science and Technology ShanghaiTech UniversityShanghaiChina Center for Excellence in Brain Science and Intelligence Technology Chinese Academy of SciencesShanghaiChina Neuroxess Co. Ltd.(Jiangxi)NanchangJiangxiChina Guangdong Institute of Intelligence Science and Technology HengqinZhuhaiGuangdongChina Tianqiao and Chrissy Chen Institute for Translational Research ShanghaiChina

In implantable electrophysiological recording systems,the headstage typically comprises neural probes that interface with brain tissue and integrated circuit chips for signal *** advancements in MEMS and CMOS technology have significantly improved these components,their interconnection still relies on conventional printed circuit boards and sophisticated *** conventional approach adds considerable weight and volume to the package,especially for high channel count *** address this issue,we developed a through-polymer via(TPV)method inspired by the through-silicon via(TSV)technique in advanced three-dimensional *** innovation enables the vertical integration of flexible probes,amplifier chips,and PCBs,realizing a flexible,lightweight,and integrated device(FLID).The total weight of the FLIDis only 25%that of its conventional counterparts relying on adapters,which significantly increased the activity levels of animals wearing the FLIDs to nearly match the levels of control animals without ***,by incorporating a platinum-iridium alloy as the top layer material for electrical contact,the FLID realizes exceptional electrical performance,enabling in vivo measurements of both local field potentials and individual neuron action *** findings showcase the potential of FLIDs in scaling up implantable neural recording systems and mark a significant advancement in the field of neurotechnology.

关键词： alloy neural recording

Mitigating kinetic hindrance of single-crystal Ni-rich cathodes through morphology modulation,nickel reduction,and lithium vacancy generation achieved by terbium doping

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Journal of Energy Chemistry 2024年第10期97卷 566-574,I0012页

作者： Jiyuan Jian Shuang Lin Guokang Han Xianglian Zhan Yinghui Shan Rang Xiao ziwei liu Dandan Sun Xin Zhang Qingjie Zhou Geping Yin Hua Huo Yulin Ma Pengjian Zuo Xinqun Cheng Chunyu Du State Key Laboratory of Space Power-sources School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001HeilongjiangChina Zibo Torch Energy Co.Ltd Zibo 255051ShandongChina

Single crystallization has proven to be effective in enhancing the capacity and stability of Ni-rich LiNi_(1-x-y)Co_(x)Mn_(y)O_(2)(SNCM)cathode materials,particularly at high cut-off ***,the synthesis of high-quality single-crystal particles remains challenging because of severe particle agglomeration and irregular ***,the limited kinetics of solid-phase Li^(+)diffusion pose a significant concern because of the extended diffusion path in large single-crystal *** address these challenges,we developed a Tb-doped single-crystal LiNi_(0.83)Co_(0.11)Mn_(0.06)O_(2)(SNCM-Tb)cathode material using a straightforward mixed molten salt sintering *** Tb-doped Ni-rich single crystals presented a quasi-spherical morphology,which is markedly different from those reported in previous ***^(4+)oping significantly enhanced the dynamic transport of Li^(+)ions in the layered oxide phase by reducing the Ni valence state and creating Li vacancies.A SNCM-Tb material with 1 at%Tb doping shows a Li^(+)diffusion coefficient up to more than 9 times higher than pristine SNCM in the non-diluted *** situ X-ray diffraction analysis demonstrated a significantly facilitated H1-H2-H3 phase transition in the SNCM-Tb materials,thereby enhancing their rate capacity and structural ***-Tb exhibited a reversible capacity of 186.9 mA h g^(-1)at 5 C,retaining 94.6%capacity after 100 cycles at 0.5 C under a 4,5 V *** study elucidates the Tb^(4+)doping mechanisms and proposes a scalable method for enhancing the performance of single-crystal Ni-rich NCM materials.

关键词： Lithium-ion batteries Ni-rich layered oxides Single crystals Tb^(4+) doping Li^(+) diffusion kinetics

胰高血糖素样肽1受体激动剂与甲状腺肿瘤关系的研究进展

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中国糖尿病杂志 2024年第3期32卷 235-237页

作者：刘子微乐岭武汉科技大学医学院 430065 解放军中部战区总医院内分泌科

胰高血糖素样肽1受体激动剂(GLP-1 RAs)可改善DM不良结局。GLP-1 RAs通过刺激啮齿类动物甲状腺C细胞异常增生和降钙素分泌等,影响甲状腺C细胞肿瘤。本文综述GLP-1RAs与甲状腺肿瘤关系的研究进展。

关键词：胰高血糖素样肽1受体激动剂甲状腺C细胞肿瘤甲状腺乳头状癌

基于改进子载波预留算法的正交频分复用信号峰均比抑制方法研究

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电子与信息学报 2024年第4期46卷 1196-1202页

作者：刘子威杨彪赵珊珊杜鸿飞南京邮电大学南京210023

由于系统对线性元器件的要求非常严格,导致目前正交频分复用(OFDM)系统产生峰值平均功率比(PAPR)过高的问题,引起OFDM和基于OFDM的雷达一体化系统的信号失真,影响系统性能。针对该问题,该文提出了基于加权最小二乘法的子载波预留法(TR)... 详细信息

由于系统对线性元器件的要求非常严格,导致目前正交频分复用(OFDM)系统产生峰值平均功率比(PAPR)过高的问题,引起OFDM和基于OFDM的雷达一体化系统的信号失真,影响系统性能。针对该问题,该文提出了基于加权最小二乘法的子载波预留法(TR)。该算法首先将OFDM设计方案中的子载波分为数据子载波和预留的空白子载波,数据子载波调制数据子载波,空白子载波调制空白数据。然后利用原始数据通过加权最小二乘法得到最佳削峰系数和削峰数据,并将削峰数据调制在空白子载波上面。最后将削峰数据叠加到原始数据上,完成PAPR的抑制。仿真表明,基于加权最小二乘法的TR算法能够在1~3次迭代下实现良好的PAPR抑制效果,并且它的收敛速度相比于传统算法有了明显的提高。

关键词：正交频分复用峰值平均功率比子载波预留法

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宽带雷达组网协同抗欺骗式干扰方法

信号处理 2024年第9期40卷 1738-1747页

作者：赵珊珊苗嘉宁刘子威南京邮电大学电子与光学工程学院江苏南京210023 南京邮电大学通信与信息工程学院江苏南京210003

现代雷达为了实现目标侦察功能,一般会使用相应的电子抗干扰技术,而强大的抗干扰能力则是其在复杂的电磁干扰条件下完成任务的重要保证。现有组网雷达抗干扰技术大多针对窄带组网雷达,而宽带雷达相对于窄带雷达具有更高的分辨率,可以探... 详细信息

现代雷达为了实现目标侦察功能,一般会使用相应的电子抗干扰技术,而强大的抗干扰能力则是其在复杂的电磁干扰条件下完成任务的重要保证。现有组网雷达抗干扰技术大多针对窄带组网雷达,而宽带雷达相对于窄带雷达具有更高的分辨率,可以探测目标更加全面的信息,达到更好的抗干扰效果。针对宽带组网雷达下的抗欺骗式干扰方法,现有研究直接类比窄带雷达抗欺骗式干扰方法,假设真实目标在每个距离单元的回波矢量独立同分布,并没有从理论上分析多视角一维距离像去相关的内在原因。针对此问题,本文推导了真实目标的三维散射中心模型投影得到目标多视角一维距离像的过程,并以此为基础,分析了真假目标一维距离像在各雷达站中的差异,及真实目标一维距离像在不同宽带雷达中的同源非一致性与转发式欺骗干扰在不同宽带雷达中的同源一致性。基于此差异,进一步提出了一种在宽带雷达组网条件下,基于一维距离像相关性差异的抗欺骗式干扰方法,设计了鉴别统计量并分析了基于累积分布函数的闭式鉴别性能。计算机仿真结果表明,本文所提方法体系能够有效对抗宽带欺骗式干扰,且鉴别性能相对于目标尺寸来说较为稳健。

关键词：电子抗干扰宽带组网雷达抗欺骗式干扰高分辨一维距离像相关系数