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A Review of Computing with Spiking Neural Networks

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Computers, Materials & Continua 2024年第3期78卷 2909-2939页

作者： Jiadong Wu Yinan Wang Zhiwei li lun Lu Qingjiang li College of Electronic Science and Technology National University of Defense TechnologyChangsha410073China

Artificial neural networks(ANNs)have led to landmark changes in many fields,but they still differ significantly fromthemechanisms of real biological neural networks and face problems such as high computing costs,excessive computing power,and so *** neural networks(SNNs)provide a new approach combined with brain-like science to improve the computational energy efficiency,computational architecture,and biological credibility of current deep learning *** the early stage of development,its poor performance hindered the application of SNNs in real-world *** recent years,SNNs have made great progress in computational performance and practicability compared with the earlier research results,and are continuously producing significant *** there are already many pieces of literature on SNNs,there is still a lack of comprehensive review on SNNs from the perspective of improving performance and practicality as well as incorporating the latest research *** from this issue,this paper elaborates on SNNs along the complete usage process of SNNs including network construction,data processing,model training,development,and deployment,aiming to provide more comprehensive and practical guidance to promote the development of ***,the connotation and development status of SNNcomputing is reviewed systematically and comprehensively from four aspects:composition structure,data set,learning algorithm,software/hardware development *** the development characteristics of SNNs in intelligent computing are summarized,the current challenges of SNNs are discussed and the future development directions are also *** research shows that in the fields of machine learning and intelligent computing,SNNs have comparable network scale and performance to ANNs and the ability to challenge large datasets and a variety of *** advantages of SNNs over ANNs in terms of energy efficiency and spatial-temporal data processing

关键词： Spiking neural networks neural networks brain-like computing artificial intelligence learning algorithm

基于Aspen Plus软件的双酚A装置反应单元流程模拟与优化

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石化技术与应用 2024年第2期42卷 108-111,148页

作者：李得伦童朝忠刘亭亭姚鑫刘旭明冯恩波李琬菁毛玲娟浙江石油化工有限公司浙江舟山316000 浙江省绿色石化技术创新中心浙江宁波315048 中国寰球工程有限公司北京100012 华东理工大学信息科学与工程学院上海200237

利用Aspen Plus流程模拟软件对离子交换树脂法合成双酚A装置反应单元工艺进行了建模,考察了反应单元进料温度、苯酚/丙酮质量比、丙酮至一段反应器比例等参数对丙酮转化率、双酚A收率及其选择性的影响,并对操作参数进行了优化。结果表明... 详细信息

利用Aspen Plus流程模拟软件对离子交换树脂法合成双酚A装置反应单元工艺进行了建模,考察了反应单元进料温度、苯酚/丙酮质量比、丙酮至一段反应器比例等参数对丙酮转化率、双酚A收率及其选择性的影响,并对操作参数进行了优化。结果表明:在单因素变化情况下,反应单元进料温度升高,或苯酚/丙酮质量比降低,或丙酮至一段反应器比例增大,均会使双酚A收率和丙酮转化率增大;在一段、二段反应器进料温度分别为65,76℃,苯酚/丙酮质量比为15.0,丙酮至一段反应器比例为1.00的优化条件下,双酚A收率、丙酮转化率分别提高3.96,4.30个百分点。

关键词：双酚A装置流程模拟 AspenPlus软件反应单元苯酚丙酮转化率收率

Effects of maternal methyl donor intake during pregnancy on ileum methylation and function in an intrauterine growth restriction pig model

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1173-1189页

作者： Yan lin Jiangnan Wu Yong Zhuo Bin Feng Zhengfeng Fang Shengyu Xu Jian li Hua Zhao de Wu lun Hua lianqiang Che Key Laboratory of Animal Disease‑Resistance Nutrition Animal Nutrition InstituteSichuan Agricultural UniversityChengdu 611130SichuanChina

Background Intrauterine growth retardation(IUGR)affects intestinal growth,morphology,and function,which leads to poor growth performance and high *** present study explored whether maternal dietary methyl donor(MET)supplementation alleviates IUGR and enhances offspring’s growth performance by improving intestinal growth,function,and DNA methylation of the ileum in a porcine IUGR *** Forty multiparous sows were allocated to the control or MET diet groups from mating until *** farrowing,8 pairs of IUGR and normal birth weight piglets from 8 litters were selected for sampling before suckling *** The results showed that maternal MET supplementation tended to decrease the IUGR incidence and increased the average weaning weight of ***,maternal MET supplementation significantly reduced the plasma concentrations of isoleucine,cysteine,urea,and total amino acids in sows and newborn *** also increased lactase and sucrase activity in the jejunum of newborn *** addition resulted in lower ileal methionine synthase activity and increased betaine homocysteine S-methyltransferase activity in the ileum of newborn *** methylation analysis of the ileum showed that MET supplementation increased the methyla-tion level of DNA CpG sites in the ileum of newborn ***-regulated differentially methylated genes were enriched in folic acid binding,insulin receptor signaling pathway,and endothelial cell *** contrast,up-regulated methylated genes were enriched in growth hormone receptor signaling pathway and nitric oxide biosyn-thetic *** Maternal MET supplementation can reduce the incidence of IUGR and increase the weaning litter weight of piglets,which may be associated with better intestinal function and methylation status.

关键词： Ileum Intrauterine growth restriction Methyl donor Methylation Sows

采收时间对不同生态区烟叶香气品质和香型风格的影响

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江西农业学报 2024年第4期36卷 13-22页

作者：武圣江贺帅李磊磊李鹏志涂永高罗贞宝蒋红娟李德仑韦克苏仲维黔陈丽萍刘琼贵州省烟草科学研究院/烟草行业山地烤烟品质与生态重点实验室贵州贵阳550081 贵州省烟草公司毕节市公司贵州毕节551700 贵州省烟草公司黔东南州公司贵州凯里556000 中国烟草总公司贵州省公司贵州贵阳550000

以云烟87中部叶为材料,研究了不同采收时间(T_(1)~T_(5)处理分别表示打顶后16、18、20、22、24 d采收)对大方蜜甜香和威宁清甜香烟叶致香物质含量和感官质量的影响。结果表明:随着采收时间的推迟,两生态区烟叶类胡萝卜素降解产物、叶绿... 详细信息

以云烟87中部叶为材料,研究了不同采收时间(T_(1)~T_(5)处理分别表示打顶后16、18、20、22、24 d采收)对大方蜜甜香和威宁清甜香烟叶致香物质含量和感官质量的影响。结果表明:随着采收时间的推迟,两生态区烟叶类胡萝卜素降解产物、叶绿素降解产物、类西柏烷类降解产物、脂肪酸类物质、生物碱类物质、其他未分类致香物质、致香物质总含量均呈先增加后降低的趋势,除大方烟区T3处理的叶绿素降解产物和T2处理的类西柏烷类降解产物最高外,其他均以T4处理的最高;除美拉德反应产物、芳香族氨基酸降解产物、类西柏烷类降解产物及其他未分类致香物质外,大方烟区烟叶的其他致香物质含量均高于威宁的,且致香物质总含量比威宁的高8.44%。1-(2,6,6-三甲基-1-环己烯-1-基)-2-丁烯-1-酮等7种物质是彰显大方烟叶蜜甜香风格的关键致香物质,1-(1H-吡咯-2-基)-乙酮等4种物质是彰显威宁清甜香风格的关键致香物质。两生态区均以打顶后22 d采收烤后烟叶的致香物质总含量最高;大方、威宁烟区分别在打顶后24、20 d采收烤后烟叶的感官质量较佳、风格更加彰显。

关键词：烤烟采收时间生态区致香物质感官质量香型风格

Accelerated reconstruction of ZIF-67 with significantly enhanced glucose detection sensitivity

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Nano Research 2024年第6期17卷 4737-4743页

作者： Huihui Jin Weihao Zeng Wei Qian lun li Pengxia Ji Zhengying li Daping He School of Information Engineering Wuhan University of TechnologyWuhan 430070China Hubei Engineering Research Center of RF-Microwave Technology and Application Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Research on metal-organic framework(MOF)-based non-enzymatic glucose sensors usually ignores the impact of the surface reconstruction degree of MOF on the activity of catalyzing glucose *** this work,we choose zeolitic imidazolate framework-67(ZIF-67),which is commonly used in glucose sensing,as a representative to investigate the influence of reconstruction degree on its structure and glucose catalytic *** employing the electrochemical activation strategy,the activity of ZIF-67 in catalyzing glucose gradually increased with the prolongation of the activation time,reaching the optimum after 2 h *** detection sensitivity of the activated ZIF-67 was 19 times higher than that of the initial ZIF-67,and the limit of detection(LOD)was lowered from 7 to 0.4μ*** findings demonstrate that the oxidation degree of ZIF-67 deepened rapidly with continuously activation and was basically reconstructed to CoOOH after 2 h activation,accompanied by a morphological change from cuboctahedral to ***,theoretical investigation revealed that ZIF-67 is not suitable as a stable glucose sensor electrode since the adsorbed glucose molecules hasten the dissociation of ligands and the breaking of Co-N bond in ***,our work has important implications for the rational design of next-generation MOF-based glucose sensors.

关键词： zeolitic imidazolate framework-67(ZIF-67) glucose oxidation electrochemical activation reconstruction CoOOH

Wideband spectrum sensing using step-sampling based on the multipath nyquist folding receiver

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defence Technology（防务技术） 2024年第1期31卷 523-536页

作者： Kai-lun Tian Kai-li Jiang Sen Cao Jian Gao Ying Xiong Bin Tang Xu-ying Zhang Yan-fei li University of Electronic Science and Technology of China Chengdu611731China China Electronics Technology Group Corporation 29th Research Institute Chengdu610036China

Wideband spectrum sensing with a high-speed analog-digital converter(ADC) presents a challenge for practical *** Nyquist folding receiver(NYFR) is a promising scheme for achieving cost-effective real-time spectrum sensing,which is subject to the complexity of processing the modulated *** this case,a multipath NYFR architecture with a step-sampling rate for the different paths is *** different numbers of digital channels for each path are designed based on the Chinese remainder theorem(CRT).Then,the detectable frequency range is divided into multiple frequency grids,and the Nyquist zone(NZ) of the input can be obtained by sensing these ***,high-precision parameter estimation is performed by utilizing the NYFR *** with the existing methods,the scheme proposed in this paper overcomes the challenge of NZ estimation,information damage,many computations,low accuracy,and high false alarm *** simulation experiments verify the effectiveness of the proposed architecture in this paper.

关键词： Wideband spectrum sensing Sub-Nyquist sampling Step-sampling Nyquist folding receiver(NYFR) Multisignal processing

Multi-physical fields distribution in billet during helical electromagnetic stirring:A numerical simulation research

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China Foundry 2024年第1期21卷 51-59页

作者： Dong Pan Qing-tao Guo Kai-lun Zhang Fu-zhi Yu Yu-ying li Yu-bao Xiao State Key Laboratory of Metal Materials for Marine Equipment and Application Anshan 114009LiaoningChina Ansteel Beijing Research Institute Co. Ltd.Beijing 102200China

Electromagnetic stirring is one of the widely applied techniques to modify the quality of casting *** from conventional rotate stirring,the helical stirring is more professional in assisting multi-dimensional flow of molten metal and eliminating solidification *** this study,the single-winding helical stirring(SWHS)was introduced,offering advantages such as smaller volume and lower electromagnetic shielding compared to traditional helical stirring *** a comprehensive numerical simulation,the stirring parameters of SWHS were adjusted to yoke inclination angle of 43°and frequency of 12 *** higher electromagnetic force and flow velocity in drawing direction,as well as the lower temperature gradient induced by the SWHS,are positive factors for homogeneous solidification of *** experimental results on Al-8%Si alloy and 0.4%C-1.1%Mn steel demonstrate that compared to rotate stirring,the SWHS process can induce better billet quality and is more effective in accelerating the equiaxed expansion and reducing element *** SWHS process can enhance the equiaxed ratio of the billet by 58.3%and reduce segregation degree of carbon element by 10.97%.Consequently,SWHS holds great promise as a potential approach for improving the quality of continuous casting billets.

关键词： billet electromagnetic stirring helical solidification element segregation numerical simulation

Micro-nanoarchitectonic of aluminum-hydrogel propellant with static stability and dynamic rheology

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 87-96页

作者： Huiyan Guo Huaiyu li Hongzhi Zhang lun Pan Chengxiang Shi Kang Xue Xiangwen Zhang Ji-Jun Zou Key Laboratory for Advanced Fuel and Propellant of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

The aluminum-water system is a promising propellant due to high energy and low signal characteristics,and the gel form is easier to store and *** this work,hydrogels of water and aluminum particles were prepared using the low-molecular-weight gellant *** various physical properties of gel systems,including the water loss rate,phase transition temperature,and centrifugal stability at different gellant and aluminum contents,were *** properties were assessed through shear thinning tests,thixotropy tests,strain sweep analysis,and frequency sweep *** microstructure of the gel was obtained through scanning electron microscopy *** results show that the aluminum-hydrogel network structure is composed of micron-scale aluminum and agarose nanosheets,and the unique micro-nanostructure endows the gel with excellent mechanical strength and thermal stability,which improve with increasing gellant and aluminum ***,the gel with 2% agarose and 20% aluminum had the best performance;the storage modulus reached 90647 Pa,which was within the linear viscoelastic region,and the maximum withstand pressure was 111.2 kPa,which was 118.8% greater than that of the pure ***,the gel demonstrates remarkable shear thinning behavior and can undergo gel-sol transformation upon shearing or heating to exceeding 114℃.

关键词： aluminum-water propellant gelled propellant rheological property mechanical strength

Standardized ileal digestibility of amino acids in soybean meal fed to non-pregnant and pregnant sows

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Journal of Animal Science and Biotechnology 2024年第1期15卷 362-373页

作者： Ke Wang Ya Wang Lei Guo Yong Zhuo lun Hua lianqiang Che Shengyu Xu Ruinan Zhang Jian li Bin Feng Zhengfeng Fang Xuemei Jiang Yan lin de Wu Institute of Animal Nutrition Key Laboratory for Animal Disease‑Resistance Nutrition of ChinaMinistry of EducationSichuan Agricultural University211 Huimin RoadWenjiang DistrictChengdu 611130SichuanChina

Background Two studies were designed to determine standard ileal crude protein(CP)and amino acid(AA)digestibility of soybean meal(SBM)from different origins fed to non-pregnant and pregnant *** solvent-extracted SBMs from soybeans produced in the USA,Brazil,and China were *** Exp.1,eight different diets were created:a nitrogen(N)-free diet and 7 experimental diets containing SBM from different origins as the only N *** non-pregnant,multiparous sows were arranged in an 8×8 Latin square design(8 periods and 8 diets).In Exp.2,the diet formula was the same as in *** gestating sows(parity 3)were assigned to 4 different diets in a replicated 4×3 Youden square design(three periods and four diets)in mid-gestation and again in late-gestation *** When fed to non-pregnant and late-gestating sows,the standardized ileal digestibility(SID)of CP and most AAs from different SBM were not significantly different(P>0.05).When fed to mid-gestating sows,the SID values for Arg,His,Lys,Phe,Cys,Gly,Ser,and Tyr in SBM 1 were lower than in SBM 4 and 5(Pde a cornerstone for accurate SBM use in sow diets.

关键词： Amino acids Sows Soybean meal Standardized ileal digestibility