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Construction of Short-Block Nonbinary LDPC Codes Based on Cyclic Codes

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China Communications 2017年第8期14卷 1-9页

作者： Hengzhou Xu baoming Bai Min Zhu Bo Zhang Yulong Zhang School of Network Engineering Zhoukou Normal UniversityZhoukou 466001China State Key Laboratory of Integrated Service Networks Xidian UniversityXi'an 710071China Zhoukou Hydrology and Water Resoures Survey Bureau of Henan Province Zhoukou 466001China

In this paper, we focus on shortblock nonbinary LDPC(NB-LDPC) codes based on cyclic codes. Based on Tanner graphs' isomorphism, we present an efficient search algorithm for finding non-isomorphic binary cyclic LDPC codes. Notice that the parity-check matrix H of the resulting code is square and not of full rank, and its row weight and column weight are the same. By replacing the ones in the same column of H with a nonzero element of fi nite fi elds GF(q), a class of NB-LDPC codes over GF(q) is obtained. Numerical results show that the constructed codes perform well over the AWGN channel and have fast decoding convergence. Therefore, the proposed NB-LDPC codes provide a promising coding scheme for low-latency and high-reliability communications.

关键词： nonbinary LDPC codes tanner graph isomorphism iterative decoding

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硅藻土改性再生骨料混凝土的抗离子侵蚀性能

混凝土 2024年第7期 141-148页

作者：赵亚婉张鸿儒张宝明何炳坚白银战中交第一公路勘察设计研究院有限公司陕西西安710065 福州大学土木工程学院福建福州350116 福州大学先进制造学院福建泉州362251 温州职业技术学院建筑工程学院浙江温州325000 中国港湾工程有限责任公司北京100000

采用硅藻土部分取代水泥制备再生骨料混凝土(RAC),研究硅藻土内掺法对RAC抗离子(氯离子、硫酸根离子)侵蚀性能的改善效果及机理。试验结果表明,硅藻土可在水泥水化进程中发挥成核效应和火山灰效应,促进水泥水化,并改善界面过渡区水化产... 详细信息

采用硅藻土部分取代水泥制备再生骨料混凝土(RAC),研究硅藻土内掺法对RAC抗离子(氯离子、硫酸根离子)侵蚀性能的改善效果及机理。试验结果表明,硅藻土可在水泥水化进程中发挥成核效应和火山灰效应,促进水泥水化,并改善界面过渡区水化产物结构,使界面过渡区更致密、厚度减小,使新砂浆水泥基体孔结构细化、大孔减少,从而减少RAC中离子侵蚀通道,减缓氯离子、硫酸根离子在RAC中的浓度积累。内掺硅藻土还提升了RAC细观尺度上各材料相(新、老砂浆及新界面过渡区)的显微硬度,减缓各材料相在硫酸根离子侵蚀下的性能劣化,从而使宏观尺度上RAC在硫酸盐侵蚀下力学性能劣化速度和程度显著降低。

关键词：再生骨料混凝土硅藻土离子侵蚀界面过渡区

Revealing the unexpected promotion effect of EuO_x on Pt/CeO_2 catalysts for catalytic combustion of toluene

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Chinese Journal of Catalysis 2019年第4期40卷 543-552,M0003页

作者： baoming Zhao Yanfei Jian Zeyu Jiang Chi He Xi’an Modern Chemistry Research Institute Xi’an 710065ShaanxiChina State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power EngineeringXi'an Jiaotong UniversityXi'an 710049ShaanxiChina Department of Chemistry College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam 31441Saudi Arabia National Engineering Laboratory for VOCs Pollution Control Material & Technology University of Chinese Academy of SciencesBeijing 101408China

Pt/Eu2O3-CeO2 materials with different Eu concentrations were prepared and applied to toluene destruction,and the remarkable promotion impact of EuOx on Pt/CeO2 can be *** characterization results reveal that the presence of EuOx significantly enhances the redox property,lattice O concentration,and Ce3+ ratio of the Pt/CeO2 material,which facilitates the dispersion and activity of Pt active sites and thus accelerates the decomposition process of *** all catalysts,a sample with an Eu content of 2.5 at.%(Pt/EC-2.5)possesses the best catalytic activity with 0.09 vol% of toluene completely destructed at 200 ℃ under a relatively high GHSV of 50000 h^-*** possible reaction pathway and mechanism of toluene combustion over Pt/Eu2O3-CeO2 samples are presented according to in-situ DRIFTS,which confirms that the toluene oxidation process obeys the Mars-van Krevelen mechanism with aldehydes and ketones as primary organic intermediates.

关键词： Pt/Eu2O3-CeO2 material Promotion effect Toluene Catalytic oxidation In-situ DRIFTS Reaction mechanism

Synthesis of two lanthanide clusters Ln^(Ⅲ)_(4)(Gd_(4) and Dy_(4)) with [2×2] square grid shape:Magnetocaloric effect and slow magnetic relaxation behaviors

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Journal of Rare Earths 2021年第9期39卷 1082-1088页

作者： Chunying Xu Zhilei Wu Chenjuan Fan Lili Yan Wenmin Wang baoming Ji Henan Key Laboratory of Function-Oriented Porous Materials.College of Chemistry and Chemical Engineering Luoyang Normal UniversityLuoyang 471934China College of Chemistry and Environmental Science Hebei UniversityBaoding 071002China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai University.Tianjin 300071China

Two isostructural tetranuclear lanthanide clusters named [Ln_(4)(L)_(4)(CH_(3) O)_(4)]·CH_(3) OH(Ln=Gd(Ⅲ) for 1,Dy(Ⅲ) for 2,H_(2) L=N’-(2-hydroxy-3-methoxybenzylidene)-6-(hydroxymethyl) picolinohydrazide) were successfully isolated by using a polydentate Schiff based ligand and Ln(Ⅲ) nitrate *** structures of 1 and 2 were characterized by X-ray structural analyses,they are held by four double deprotonated ligands L2-.In them all the lanthanide ions are eight-coordinated and distributed over four vertices of a parallelogram,presenting a Ln4 cluster with a strict [2 × 2] square grid *** details of magnetic analysis show that 1 displays weak anti-ferromagnetic exchange between neighboring Gd(Ⅲ) ions through carboxylate oxygen and methanol oxygen ligand ***,1 exhibits significant magnetocaloric effect with the maximum entropy change-ΔSm value of 28.5 J/(kg K) for ΔH=7.0 T at 2.0 *** compound 2,remarkable slow magnetic relaxation behaviors are observed in the presence of zero magnetic field with τ0=1.02 × 10^(-6) s and energy barrier ΔE/kB=43.24 K.

关键词： Lanthanide clusters [2×2]square grid Anti-ferromagnetic couplings Magnetocaloric effect Slow magnetic relaxation Rare earths

Sustainable utilization of biological resources from coastal wetlands in China

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Chinese Science Bulletin 2013年第19期58卷 2270-2275页

作者： TANG BoPing ZHANG DaiZheng GE baoming ZHANG HuaBin Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection Yancheng Teachers University

The main utilization of biological resources from coastal wetlands in China and the major limiting factors on sustainable utilization of these resources are reviewed. Strategies for the sustainable utilization of coastal wetlands are proposed. These include further studies on saline agriculture and wetland ecosystems, optimizing methods for maximizing metabolic production from organisms, developing microbial resources and efficient utilization of biological genetic resources, and exploiting bioenergy from coastal wetlands.

关键词：微生物资源可持续利用沿海湿地中国湿地生态系统生物遗传资源盐土农业代谢产物

Improving utilization of nests and decreasing mislaid eggs with narrow width of group nests

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International Journal of Agricultural and Biological Engineering 2018年第1期11卷 83-87页

作者： Hongya Zheng baoming Li Gang Chen Chaoyuan Wang College of Water Resources and Civil Engineering China Agricultural UniversityBeijing 100083China Key Laboratory of Agricultural Engineering in Structure and Environment Ministry of AgricultureBeijing 100083China Beijing Engineering Research Center for Livestock and Poultry Healthy Environment Beijing 100083China

Provision of nest boxes is necessary for laying hens,especially in non-cage *** study investigated the effects of nest width on nest utilization and mislaid ***-Line Browns hens were transferred from conventional cages to perchery pens at 12 weeks of *** experiments were conducted to mutually verify the hypothesis that narrowing group nests would improve nest utilization and reduce mislaid *** experiment 1,group nests of 150 cm wide in two pens were partitioned at intervals of 50 cm and 37 cm,*** experiment 2,partition panels were removed after *** number of mislaid eggs and nest eggs in each pre-set section were *** indicated that narrowing group nests had positive effects on improving usage uniformity and efficiency of group *** eggs were more evenly distributed on the egg belt in both narrowed group nests,which was indicated by the significant decrease of variance among different sections(p<0.001).The proportion of mislaid eggs decreased by 3.5%in 37 cm treatment(p<0.05)and 4.7% in 50 cm treatment(p<0.001),*** expected,reuse of the 150 cm group nests after removal of partition panels lowered the usage uniformity of group nests.A growth of three percentage points was found for the proportion of mislaid eggs after removing the partition panels in 50 cm *** present results indicated that it is the width of the nest box that works for a better use of group *** conclusion,adding partition panels at intervals of 50 cm and 37 cm in group nests both are effective on nest usage and decreasing the occurrence of mislaid eggs.

关键词： group nest nest width utilization mislaid eggs hen house non-cage system bird welfare

基于BP神经网络的某型飞机部件装配工时估算方法

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郑州航空工业管理学院学报 2024年第4期42卷 72-78页

作者：刘宝明刘鑫荣宋国秋沈阳航空航天大学工程训练中心辽宁沈阳110136 沈阳航空航天大学航空宇航学院辽宁沈阳110136 中航工业沈阳飞机工业(集团)有限公司辽宁沈阳110850

传统飞机部件装配工时定额依靠人工经验确定,导致装配工时预测准确性低、稳定性差。为解决该问题,提出一种基于BP神经网络的飞机部件装配工时估算方法。首先,以某型飞机机身装配为例,分析其装配工艺流程,划分典型装配工艺环节并归纳装... 详细信息

传统飞机部件装配工时定额依靠人工经验确定,导致装配工时预测准确性低、稳定性差。为解决该问题,提出一种基于BP神经网络的飞机部件装配工时估算方法。首先,以某型飞机机身装配为例,分析其装配工艺流程,划分典型装配工艺环节并归纳装配工时主要集中工艺环节,从装配对象、装配要求两方面分析装配工时的影响因素。然后,构建不同工艺环节理论装配工时预测神经网络模型,并提出操作技能水平、操作姿态修正系数,实现了某型飞机机身装配工时定额准确估算。最后,设计开发了基于CAA技术的装配工时影响因素提取系统,将所得信息输入工时定额计算模型得到预测值并与实际装配工时对比,验证了所提方法的可行性与实用性。

关键词：飞机部件典型装配工艺 BP神经网络工时定额估算 CAA

Hydroxycalciopyrochlore, A New Mineral Species from Sichuan, China

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Acta Geologica Sinica(English Edition) 2014年第3期88卷 748-753页

作者： YANG Guangming LI Guowu XIONG Ming PAN baoming YAN Chenjie State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Crystal Structure Laboratory China University of Geosciences

Hydroxycalciopyrochlore,ideally （Ca,Na,U,□）2（Nb,Ti）2O6（OH）,cubic,is a new mineral species （IMA2011-026） within the pyrochlore supergroup that was found occurring at the Maoniuping mine,Mianning County,Xichang prefecture,Sichuan Province,southwest *** mineral is found in an alkali feldspar granite rare-earth ore deposit （26-27 Ma）.Associated minerals include calcite,barite,celestine,albite,aegirine,aegirine-augite,fluorite,parasite-（Ce）,thorite,thorianite,zircon,galena,sphalerite,magnetite,and *** occur mostly as octahedra,and less often as dodecahedra and tetrahexahedra or combinations *** occur with an allotriomorphic habit with a thick triangular tabular *** generally range from 0.1 to 1 mm in *** mineral is brownishblack,greenish-black and black on fresh sections with a brown *** crystal is translucent,and has a greasy lustre on fresh *** is metamict without any observed parting or cleavage and with a conchoidal *** Vickers microhardness is 572 kg/mm2 （5-6 on the Mohs hardness scale）.The density measured by hydrostatic weighing is 5.10（3） g/*** strongest four reflections in the X-ray powder-diffraction pattern [d in（A）（Ⅰ） hkl] are：2.9657 （100） 2 2 2,1.8142 （34） 0 4 4,1.5463 （21） 2 2 6,2.5688 （18） 0 0 *** unit-cell parameters are a =10.381（4）（A）,V=1118.7（7）（A）3,Z =*** structure was solved and refined in the space group Fd3m with R =*** empirical formula is （Ca0.74Na0.5sU0.40Ce0.05Fe0.02□0.21）2.00（Nb1.15Ti0.s0Ta0.03Al0.01Mg0.01）2.00O6.02 [（OH）1.01F0.09]1.10,on the basis of 2 atoms of B pfu; the simplified formula is （Ca,Na,U,□）2（Nb,Ti）2O6（OH）.Type material is deposited in the Geological Museum of China,Beijing,People＇s Republic of China,catalogue number M11800.

关键词： Mineralogy Hydroxycalciopyrochlore pyrochlore supergroup crystal structure Sichuanprovince

Scorpion ethanol extract and valproic acid effects on hippocampal glial fibrillary acidic protein expression in a rat model of chronic-kindling epilepsy induced by lithium chloride-pilocarpine

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Neural Regeneration Research 2012年第6期7卷 426-433页

作者： Yi Liang Hongbin Sun Liang Yu baoming He Yan Xie Department of Neurology Sichuan Academy of Medical Sciences ＆ Sichuan Provincial People＇s Hospital Chengdu 610072 SichuanProvince China

The present study analyzed the effects of ethanol extracts of scorpion on epilepsy prevention and hippocampal expression of glial fibrillary acidic protein in a lithium chloride-pilocarpine epileptic rat model. Results were subsequently compared with valproic acid. Results showed gradually- increased hippocampal glial fibrillary acidic protein expression following model establishment; glial fibrillary acidic protein mRNA expression was significantly increased at 3 days, reached a peak at 7 days, and then gradually decreased thereafter. Ethanol extracts of scorpion doses of 580 and 1 160 mg/kg, as well as 120 mg/kg valproic acid, led to a decreased number of glial fibrillary acidic protein-positive cells and glial fibrillary acidic protein mRNA expression, as well as decreased seizure grades and frequency of spontaneously recurrent seizures. The effects of 1 160 mg/kg ethanol extracts of scorpion were equal to those of 120 mg/kg valproic acid. These results suggested that the anti-epileptic effect of ethanol extracts of scorpion were associated with decreased hippocampal glial fibrillary acidic protein expression in a rat model of lithium chlofide-pilocarpine induced epilepsy.

关键词： Chinese herbs epilepsy glial fibrillary acidic protein lithium chloride-pilocarpine scorpion ethanol extraction valproic acid