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A method of improving SFDRs of 1-bit signals for a monobit receiver

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Journal of Systems Engineering and Electronics 2022年第2期33卷 330-339页

作者： JI Pengfei SHI Qingzhan lv huan YUAN Naichang School of Electronic Sciences National University of Defense TechnologyChangsha 410073China

This paper proposes a method to improve the spu-rious-free dynamic ranges(SFDRs)of 1-bit sampled signals greatly,which is very beneficial to multi-tone signals ***,the relationship between the fundamental component and the third harmonic component of 1-bit sampled signals is analyzed for determining four contiguous special frequency bands,which do not contain any third harmonics inside and co-ver 77.8%of the whole Nyquist sampling frequency ***,we present a special 4-channel monobit receiver model,where appropriate filter banks are used to obtain four desired pass bands before 1-bit quantization and each channel can sample and process sampled data independently to achieve a good in-stantaneous dynamic range without sacrificing the real-time per-formance or computing *** simulation results show that the proposed method effectively eliminates the effect of the most harmonics on SFDRs and the mean SFDR is increased to to 20 ***,the multi-signals simulation results indicate that the maximum amplitude separation(dynamic range)of two signals in each channel is 12 dB while the proposed monobit re-ceiver can deal with up to eight simultaneous arrival *** general,the designing method proposed in this paper has a po-tential engineering value.

关键词： 1-bit signal monobit third harmonic component spurious-free dynamic range(SFDR)

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基于功率流理论大底盘双塔楼减震控制研究

自然灾害学报 2024年第5期33卷 188-198页

作者：吕欢张尚荣唐响巨雪熊洋何佳蔓宁夏大学土木与水利工程学院宁夏银川750021

在地震作用下,大底盘双塔楼结构采用隔震层和阻尼器协同控制方案有较好的控制效果,但该体系下各子结构间的能量流动并未被深入研究。文中将大底盘双塔楼复合被动控制体系简化为分布参数体系,利用多目标粒子群(multi-objective particle ... 详细信息

在地震作用下,大底盘双塔楼结构采用隔震层和阻尼器协同控制方案有较好的控制效果,但该体系下各子结构间的能量流动并未被深入研究。文中将大底盘双塔楼复合被动控制体系简化为分布参数体系,利用多目标粒子群(multi-objective particle swarm optimization,MOPSO)算法,得到阻尼器最优参数。以此为基础,探究左塔频率和阻尼比变化时,各塔楼功率流方差、功率流流向以及随机功率流时变方差的变化情况。研究表明:采用一体化的设计流程可以增强大底盘双塔楼控制体系的耗能能力。隔震层和阻尼器使得具有底部隔震的右塔类似于一个大型的调谐质量阻屁器(tuned mass damper,TMD)控制装置。同时左、右塔楼不对称设计提供的动力差异进一步提升结构的减震性能。此时,较低楼层的能量将流入隔震层,而较高楼层的能量则由阻尼器进行吸收耗散。复合被动控制方案可使得结构更快地进入稳定状态。上述方案还可大幅降低随机功率流时变方差峰值。

关键词：大底盘双塔楼分布参数体系功率流复合被动控制减震效果

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鞋类产品标识新、旧标准解析

中国纤检 2024年第9期 86-88页

作者：穆奎唐孔科高勇吕欢山东省产品质量检验研究院山东济南250102

本文通过QB/T 2673新、旧标准比对和解析的方式,从标准的规范性引用文件、术语定义、标识内容和标注要求等方面对新、旧标准进行了详细的解析与研究,并举例说明标识的规范标注,有利于新标准的实施和宣贯,对鞋类产品的生产企业和检验机... 详细信息

本文通过QB/T 2673新、旧标准比对和解析的方式,从标准的规范性引用文件、术语定义、标识内容和标注要求等方面对新、旧标准进行了详细的解析与研究,并举例说明标识的规范标注,有利于新标准的实施和宣贯,对鞋类产品的生产企业和检验机构有一定的指导作用。

关键词：鞋类产品标识材质标注

维普期刊数据库博看期刊

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国内外野外消防服标准对比与分析

中国个体防护装备 2024年第3期 37-44页

作者：吕欢张希文田桓荣李丽陕西元丰纺织技术研究有限公司陕西西安710038

为更好地优化森林、荒地等野外消防灭火防护服功能,进一步完善国内森林防火服防护性能要求,将国内常用的森林防火服标准与欧美国家野外消防服标准中的阻燃性、热稳定性、耐辐射热、热湿舒适性、力学性能等关键性技术指标进行研究分析。... 详细信息

为更好地优化森林、荒地等野外消防灭火防护服功能,进一步完善国内森林防火服防护性能要求,将国内常用的森林防火服标准与欧美国家野外消防服标准中的阻燃性、热稳定性、耐辐射热、热湿舒适性、力学性能等关键性技术指标进行研究分析。根据野外消防服装实际应用需求,从阻燃热防护性能、热湿舒适性能、完善防护服装等级分类三个方面提出了我国森林防火服装标准修订建议。

关键词：野外消防服热防护性能辐射热热湿舒适性

Semi-empirical and semi-quantitative lightweight shielding design method

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Nuclear Science and Techniques 2023年第3期34卷 109-124页

作者： Song-Chuan Zheng Qing-Quan Pan huan-Wen lv Song-Qian Tang Xiao-Jing Liu College of Smart Energy Shanghai Jiao Tong UniversityShanghai 200240China School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610200China

The lightweight shielding design of small reactors is a popular research *** on a small helium-xenon-cooled solid reactor,the effects of neutron and photon shielding sequence and the number of shielding layers on the radiation dose were first *** was found that when photons were shielded first and the number of shielding layers was odd,the radiation dose could be significantly *** reduce the weight of the shielding body,the relative thickness of the shielding layers was optimized using the genetic *** optimized scheme can reduce the radiation dose by up to 57%and reduce the weight by 11.84%.To determine the total thickness of the shielding layers and avoid the local optimal solution of the genetic algorithm,a series of formulas that describes the relationship between the total thickness and the radiation dose was developed through large-scale calculations.A semi-empirical and semi-quantitative lightweight shielding design method is proposed to integrate the above shielding optimization method that verified by the Monte Carlo ***,a code,SDIC1.0,was developed to achieve the optimized lightweight shielding design for small *** was verified that the difference between the SDIC1.0 and the RMC code is approximately 10%and that the computation time is shortened by 6.3 times.

关键词： Small reactor Lightweight Shielding calculation Genetic algorithm

Analysis of the Effect of Optical Properties of Black Carbon on Ozone in an Urban Environment at the Yangtze River Delta,China

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Advances in Atmospheric Sciences 2021年第7期38卷 1153-1164页

作者： Junlin AN huan lv Min XUE Zefeng ZHANG Bo HU Junxiu WANG Bin ZHU Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science and TechnologyNanjing 210044China Chinese Academy of Meteorological Sciences Beijing 100081China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029China Inner Mongolia Meteorological Bureau Hohhot 010051China

Black carbon(BC)reduces the photolysis coefficient by absorbing solar radiation,thereby affecting the concentration of ozone(O_(3))near the *** influence of BC on O_(3)has thus received much *** this study,Mie scattering and the tropospheric Ultraviolet and Visible radiation model are used to analyze the effect of BC optical properties on *** with data of O_(3)precursors in Nanjing in 2014,an EKMA curve is drawn,and the variations in O_(3)concentration are further investigated using a zero-dimensional box mechanism model(NCAR MM).When O_(3)precursors are unchanged,radiation and O_(3)show a highly similar tendency in response to changing BC optical properties(R=0.997).With the increase of modal radius,the attenuation of fresh BC to radiation and O_(3)first trends upward before *** the mixing process,the attenuation of BC to radiation and O_(3)presents an upward tendency with the increase of relative humidity but decreases rapidly before increasing slowly with increasing thickness of *** addition,mass concentration is another major *** the BC to PM_(2.5)ratio increases to 5%in Nanjing,the radiation decreases by approximately 0.13%-3.71%while O_(3)decreases by approximately 8.13%-13.11%.The radiative effect of BC not only reduces O_(3)concentration but also changes the EKMA *** with the NO_(x)control area,radiation has a significant influence on the VOCs control *** aerosol optical depth(AOD)increases by 17.15%,the NO_(x)to VOCs ratio decreases by 8.27%,and part of the original NO_(x)control area is transferred to the VOCs control area.

关键词： black carbon ozone radiation optical properties EKMA curve

GB/T 32614《户外运动服装冲锋衣》新、旧标准对比

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中国纤检 2024年第9期 92-94页

作者：李姗姗李文川唐孔科吕欢山东省产品质量检验研究院山东济南250102

GB/T 32614-2023《户外运动服装冲锋衣》于2024年4月1日开始实施,其相比GB/T 32614-2016《户外运动服装冲锋衣》变化较大,主要技术变化有22处,涉及适用范围、规范性引用文件、技术考核指标、检测方法、判定规则等内容。本文从标准的结... 详细信息

GB/T 32614-2023《户外运动服装冲锋衣》于2024年4月1日开始实施,其相比GB/T 32614-2016《户外运动服装冲锋衣》变化较大,主要技术变化有22处,涉及适用范围、规范性引用文件、技术考核指标、检测方法、判定规则等内容。本文从标准的结构和内容两大方面进行新、旧标准对比,为冲锋衣生产企业、相关检测机构深入细化理解新标准提供参考。

关键词：冲锋衣新、旧标准对比

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随钻核磁仪器数字电路在系统编程实现方法

价值工程 2024年第15期43卷 112-114页

作者：陈敬智张嘉伟吕焕军娄伟中海油田服务股份有限公司油田技术事业部北京101149

受钻井过程中冲击和振动的影响,随钻核磁测井仪器的内部电路需要特殊封装,使得DSP和FPGA组成的数字电路系统不能正常通过JTAG接口升级程序。本文提出了一种基于串口总线的在系统编程技术。根据FLASH的配置特性和JTAG接口协议的特点,以DS... 详细信息

受钻井过程中冲击和振动的影响,随钻核磁测井仪器的内部电路需要特殊封装,使得DSP和FPGA组成的数字电路系统不能正常通过JTAG接口升级程序。本文提出了一种基于串口总线的在系统编程技术。根据FLASH的配置特性和JTAG接口协议的特点,以DSP作为主控制器,利用自编写的底层程序将串口传输的配置文件分别烧写进DSP和FPGA内部FLASH中,实现了DSP和FPGA的在系统编程(ISP)。利用对TI TMS320F2812和Actel A3P1000的数字电路的系统调试,证明这种方法可靠性高、现场操作方便。

关键词：随钻测井仪器串口 JTAG 在系统编程

维普期刊数据库博看期刊

Research on vibration energy harvesting technology of power equipment based on alternating magnet array

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High Voltage 2024年第2期9卷 336-345页

作者： Pinlei lv Chengyu Fan Aijun Yang huan Yuan Jifeng Chu Mingzhe Rong Xiaohua Wang State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi'anChina State Grid Sichuan Electric Power Research Institute ChengduChina

Vibration with a frequency of 100 Hz is widely distributed in the power equipment,and it can provide a new way to supply energy for sensors by vibration energy *** vibration energy harvesting method based on electromagnetic induction principle was studied through the arrayed structure of magnets and *** magnetic field models were established for four magnet array structures and it was found that the alternating magnet array has the largest magnetic flux and magnetic flux *** on the alternating magnet array,prototypes of energy harvester with vertical and parallel movement mode were *** structural parameter optimisation analysis,two different energy harvesters were fabricated and it was found that the energy harvester with a parallel movement mode has better output *** energy harvester could provide output voltage/current and power of 8.35 V/17.39 mA and 15.13 mW(matched resistance is 200Ω)at an acceleration of 5 m⋅s^(-2).The 100 mF capacitor could be charged to 2.72 V within 300 s,and the final voltage of the capacitor is greater than 3 V,which could sustainably drive commercial wireless temperature/humidity sensors.

关键词： power energy alternating