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A robust vector tracking loop structure based on potential bias analysis

Chinese Journal of Aeronautics 2024年第4期37卷 405-420页

作者： Qiongqiong JIA Yiran LuO Bing Xu Li-ta HSu Renbiao Wu Tianjin Key Lab for Advanced Signal Processing Civil Aviation University of ChinaTianjin 300300China Interdisciplinary Division of Aeronautical and Aviation Engineering The Hong Kong Polytechnic University999077Hong KongChina Department of Geomatics Engineering University of CalgaryCalgary T2N1N4Canada

This paper proposes a robust vector tracking loop structure based on potential bias analysis. The influence of four kinds of biases on the existing two implementations of Vector Tracking Loops(VTLs) is illustrated by theoretical analysis and numerical simulations, and the following findings are obtained. Firstly, the initial user state bias leads to steady navigation solution bias in the relative VTL, while new mea.urements can eliminate it in the absolute VTL. Secondly, the initial code phase bias is transferred to the following navigation solutions in the relative VTL, while new mea.urements can eliminate it in the absolute VTL. Thirdly, the user state bias induced by erroneous navigation solution of VTLs can be eliminated by both of the two VTLs. Fourthly,the multipath/NLOS likely affects the two VTLs, and the induced tracking bias in the duration of the multipath/NLOS would decrease the performance of VTLs. Based on the above analysis,a robust VTL structure is proposed, where the absolute VTL is selected for its robustness to the two kinds of initialization biases;meanwhile, the instant bias detection and correction method is used to improve the performance of VTLs in the duration of the multipath/NLOS. Numerical simulations and experimental results verify the effectiveness of the proposed robust VTL structure.

关键词： Global Navigation Satellite System(GNSS) Vector Tracking Loop(VTL) Multipath Non-Line-of-Sight(NLOS) Tracking bias propagation Least Absolute Shrinkage and Selection Operator(LASSO)

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Protection of steel hooks embedded in glass-fiber-reinforced concrete against macrocell corrosion

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Petroleum Research 2024年第2期9卷 317-326页

作者： Husnu Gerengi Muhammed Maraşlı Marziya Rizvi Beni Kohen Ismail taşkıran Corrosion Research Laboratory Department of Mechanical EngineeringDuzce University81620DuzceTurkey Department of Engineering and Applied Sciences University of BergamoBGItaly Fibrobeton Company R&D Center DuzceTurkey Department of Chemistry Babasaheb Bhimrao Ambedkar UniversityLucknow226003U.PIndia

This study eva.uated the corrosion behavior of steel hooks embedded in GFRC,which were protected by a zinc-rich(96%Zn)galvanizing *** coating provided the hooks with active cathodic protection and a passive physical *** corrosion may form when the anode is smaller than the total steel ***,the steel hooks at the embedment juncture were additionally sealed against water ingress and air exchange using a construction *** study was conducted in three phases in a salt-spray ***,the electrogalvanized steel hooks embedded in GFRC were allowed to freely corrode for 7 *** the second phase,the electrogalvanized steel hooks were painted with the zinc-rich coating and observed over 7 *** the third phase,the steel hooks were protected by the zinc-rich coating together with a primer and construction sealant,and observed over 7 *** eva.uate the electrogalvanized hooks and the corrosion products formed,the thickness of the material was *** on the metal surface was inferred by studying the surface morphology of the hooks at various points of contact and after different periods of time.

关键词： Steel rebars Concrete corrosion GFRC Galvanization Sealant

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祁连山排露沟流域青海云杉天然更新空间关联性研究

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干旱区资源与环境 2024年第1期38卷 161-170页

作者：刘济萌刘贤德马瑞赵维俊敬文茂拓锋王艳霞甘肃农业大学林学院兰州730070 甘肃省祁连山水源涵养林研究院(甘肃祁连山森林生态系统国家定位观测研究站) 张掖734000 兰州大学草地农业科技学院兰州730000

青海云杉作为祁连山森林生态的建群种,其天然更新的空间关联性及集聚模式对种群更新具有重要意义。于2022年8月对祁连山排露沟流域海拔2800-3300m样地内的青海云杉林进行每木检尺,研究将胸径小于50mm的青海云杉植株划为更新苗,并选取更... 详细信息

青海云杉作为祁连山森林生态的建群种,其天然更新的空间关联性及集聚模式对种群更新具有重要意义。于2022年8月对祁连山排露沟流域海拔2800-3300m样地内的青海云杉林进行每木检尺,研究将胸径小于50mm的青海云杉植株划为更新苗,并选取更新苗胸径、株高两个生物指标,通过空间自相关分析探究其胸径、株高的空间关联性及集聚模式。结果表明:1)不同海拔更新苗胸径、株高均表现为空间正自相关,胸径空间关联性呈现为2800m>3100m>3000m>2900m>3300m,株高空间关联性呈现为2800m>2900m>3100m>3000m>3300m,仅3200m样地胸径和株高均表现为不显著的空间负自相关,表明更新苗胸径和株高的空间关联性随着海拔的升高而逐渐降低。2)不同样地更新苗胸径和株高个体间空间正自相关的数量远多于空间负自相关,表明青海云杉更新个体的生长有益于邻近径级个体的生长。3)更新苗胸径和株高整体呈现为低低集聚比高高集聚更为集中,且相互间分界明显,表明邻近径级的植株间关系较为协调,径级差异较大的植株间排斥效应较为明显。4)更新苗胸径和株高均表现出高高集聚和低低集聚交替分布的现象,且随着海拔的升高,高高集聚现象逐渐消失。

关键词：青海云杉天然更新空间自相关空间集聚

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Neurodevelopmental in Relation to Breastfeeding–Experiences among Hungarian Preterm Infants at 12 Months of Corrected Age:Empirical Study

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International Journal of Mental Health Promotion 2022年第5期24卷 699-709页

作者： Anna Szabina Szele Beáta Erika Nagy Department of Pediatrics Faculty of MedicinePediatric Psychology and Psychosomatic UnitKálmán Laki Doctoral SchoolUniversity of DebrecenDebrecen4032Hungary Department of Pediatrics Faculty of MedicinePediatric Psychology and Psychosomatic UnitUniversity of DebrecenDebrecen4032Hungary

Preterm and low birth weight infants are at higher risk of neurodevelopmental outcomes;breastfeeding offers sev-eral beneﬁcial aspects for *** study aimed to describe the average neurodevelopmental outcomes of pre-term infants and examine the associations between neurodevelopment and breastfeeding among Hungarian preterm infants at 12 months of corrected age.154 preterm infants with low birth weight(a.ure the cognitive,language and motor skills of infants;breastfeeding data was obtained through parental *** analyze data,independent sample t-test or the Welch t-test,Mann-Whitney tests,Chi-square tests of independence and Spearman’s rank correlation test were used *** the risk of developmental delay,Receptive and Expressive language and Fine motor subscales were the *** of the associations between breastfeeding and neurodevelopmental per-formance identiﬁed signiﬁcantly higher cognitive(u=2047.5;P=0.023)andﬁne motor(u=2096.0;P=0.037)skills in infants who were *** found signiﬁcant positive correlations between the duration of breastfeeding and cognitive,expressive language andﬁne motor *** study draws the attention to the importance of breastfeeding and early *** research is required to examine the ca.ual relationship between neurodevelopmental outcomes and breastfeeding.

关键词： Preterm infants low birth weight breastfeeding duration of breastfeeding neurodevelopmental outcomes

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Classification of topological trivial matter with non-trivial defects

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Science Bulletin 2019年第9期64卷 575-579页

作者： Lokman Tsui Zi-Xiang Li Yen-ta Huang Steven G. Louie Dung-hai Lee Department of Physics University of California Materials Sciences Division Lawrence Berkeley National Laboratory

In this paper, we apply the K-theory to classify topological trivial fermionic phases which, nonetheless,host symmetry-protected non-trivial defects. An important implication of our work is that the existence of Majorana zero mode in the vortex core is neither a necessary nor a sufficient condition for the superconductor in question being topologically non-trivial.

关键词： Majorana zero mode Symmetry protected topological phase Topological superconductor Topological defect K-theory

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三通平衡法电针治疗腰椎间盘突出症的临床疗效研究

三通平衡法电针治疗腰椎间盘突出症的临床疗效研究

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作者：陈隆达（Chen Lung ta）广州中医药大学

学位级别：硕士

目的:本研究探讨三通平衡法电针治疗腰椎间盘突出症的临床疗效研究,提出治疗新思路并提供客观依据。方法:本研究依据诊断、纳入和排除标准,纳入2021年12月-2022年3月广州中医药大学第一附属医院的病例,确定合格受试者共60例,按照随机数... 详细信息

目的:本研究探讨三通平衡法电针治疗腰椎间盘突出症的临床疗效研究,提出治疗新思路并提供客观依据。方法:本研究依据诊断、纳入和排除标准,纳入2021年12月-2022年3月广州中医药大学第一附属医院的病例,确定合格受试者共60例,按照随机数字分组方法,分为治疗组、对照组各30例。治疗方法的主穴,治疗组(三通平衡法)以一通经络(命门、中脘、关元、腰阳关、外丘、金门)、二通脏腑(肾俞、膀胱俞)、三通元神(百会、内关)。对照组(常规法)以大肠俞(双侧)、委中(双侧)、环跳(双侧)、昆仑(双侧)、阿是穴。治疗方法两组采用相同配穴、电针、疗程,随证配穴为肾虚(肾俞)、瘀血(膈俞)、湿热(大椎)、寒湿(腰阳关),电针为疏密波5/100Hz,疗程为一个疗程是每周三次(治疗后休息一天),持续四周。在治疗前后、治疗后30日,收集两个量表的评分,有次要指标①疼痛程度量表(疼痛分级-感觉)(疼痛分级-情感)(目测类比疼痛)(现有疼痛强度)、主要指标②下腰痛程度量表(主观评分)(临床体征)(日常活动)(总分),经SPSS 22.0进行统计分析,以确定两组的临床结果。结果:1、比较两组疗程前的一般情况:两组的年龄、性别、病程,经统计分析后,(P>0.05)皆无统计差异,具可比性。2、比较两组疗程前两个程度量表的评分:两组的①疼痛程度量表、②下腰痛程度量表的评分,经统计分析后,(P>0.05)皆无统计学差异,具可比性。3、比较两组疗程前后两个程度量表的评分差值:两组两个量表的评分差值,经统计分析后,分别为P=0.003、P=0.000,(Pu检验,(P0.05)无统计学意义除外。4、比较两组疗程后的临床疗效(依下腰痛程度量表为评定标准):两组0例失访,治疗组总有效率100%(治愈0例、显效17例、有效13例、无效0例);对照组总有效率93.3%(治愈0例、显效0例、有效28例、无效2例),两组疗程后的下腰痛程度量表的评分,经统计分析后,(P0.05)无统计意义除外。结论:1、两组试验皆显示,患者疼痛有减少(根据①疼痛程度量表)、患者腰痛有改善(根据②下腰痛程度量表),但三通平衡法的效果略好。2、在腰椎间盘突症的总体临床疗效(根据②下腰痛程度量表),三通平衡法是具备整体优势,缓解长短期症状都皆有很好的作用。说明在改善腰椎间盘突出症的整体、远期疗效上,治疗组(三通平衡法)较优。综上所述,三通平衡法的改善各项症状更佳、病情更稳、远疗更好、复发更低等优势,值得临床运用推广。

关键词：三通平衡法电针腰椎间盘突出症

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大麦马铃薯间作模式对大麦苗抗氧化酶活性的影响

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中国种业 2024年第3期 82-90页

作者：赵塔杨丽娥杨晓梦普晓英李霞官秀娇杨砚斌杨加珍和习琼曾亚文云南大学资源植物研究院昆明650504 云南省农业科学院生物技术与种质资源研究所昆明650205 云南省丽江市农业科学研究所丽江674100

为探究间作对分蘖期大麦苗抗氧化酶活性的影响,以64个云南大麦品种(系)与紫色马铃薯间作,大麦单作为对照,揭示分蘖期大麦苗不同种植模式、不同棱型、不同用途类型间的大麦苗4个抗氧化酶活性的差异。结果表明,间作模式下大麦SOD(1609.31u... 详细信息

为探究间作对分蘖期大麦苗抗氧化酶活性的影响,以64个云南大麦品种(系)与紫色马铃薯间作,大麦单作为对照,揭示分蘖期大麦苗不同种植模式、不同棱型、不同用途类型间的大麦苗4个抗氧化酶活性的差异。结果表明,间作模式下大麦SOD(1609.31u/g)、CAT(159.16u/g)、POD(334.70u/g)、PPO(102.30u/g)活性显著高于单作,且单作、间作下不同品种间4个抗氧化酶活性水平均存在差异;不同棱型间大麦苗抗氧化酶活性表现为间作模式下二棱大麦抗氧化酶活性最高,单作模式下多棱大麦抗氧化酶活性最低;不同类型大麦间作模式下啤酒大麦品种抗氧化酶活性最高,青稞品种次之,饲料大麦品种抗氧化酶活性最低。用隶属函数法对间作模式下大麦抗氧化性综合评价,初步筛选出云啤麦MF20-5、宽颖大麦、MF20-16等抗氧化性综合评价前10的品种(系),作为与马铃薯间作下抗氧化性强的云南大麦品种(系)。

关键词：间作大麦抗氧化酶棱型用途类型分蘖期

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Geochemical characterization of Granitoids in Katchuan Irruan area: further evidence for pera.uminous and shoshonitic compositions and post-collisional setting of granitic rocks in the Precambrian Basement Complex of Nigeria

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Acta Geochimica 2019年第5期38卷 734-752页

作者： Chinedu u.Ibe Smart C.Obiora Department of Geology University of Nigeria

Petrographic studies on Granitoids from Katchuan Irruan and adjoining areas,southeastern Nigeria.ha. shown that they are garnetiferous biotite granite,aplitic granite,porphyritic hornblende biotite granite,porphyritic muscovite biotite granite,weakly foliated leucogranodiorite and simple *** are closely associated with the Precambrian Basement Complex rocks which they *** analysis shows that the rocks consist of quartz(10%-25%),oligoclase(10%-30%),K-feldspar(15%-35%),biotite(3%-25%),with occasional garnet,hornblende,muscovite,and accessory chlorite,haematite and *** data indicates that the rocks are generally shoshonitic,alkali-calcic to calcic,ferroan and *** are enriched in large ion lithophile elements as well as high field strength elements(Hf,ta,Yb,Sm,Zr and Y).Their trace elements and REE patterns are similar,indicating that they are *** are characterized by high fractionation factor(La/Yb)N(3.04-228.44)and pronounced negative Eu anomalies(Eu/Eu*)(0.23-0.71).Their overall geochemical fea.ures indicate that they were most likely derived from partial melting of crustal materials in an orogenic(post-collisional)tectonic *** are therefore related to the Pan-African granites,otherwise known as the Older Granites which were emplaced during the Pan African orogenic event.

关键词： Pan African Partial melting Post-collisional Precambrian Older Granites Orogenic

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Inner Mongolia Grassland Song and Dance Ensemble Tours the u.S.

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China & The World Cultural Exchange 2005年第11期71卷 12-13页

作者： ta Na

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Trace and rare-earth element geochemistry: A tool for petrogenetic and geotectonic modeling of ensimatic ortho-amphibolites from Pan-African belt of Obudu Plateau, Southeastern Nigeria

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Chinese Journal Of Geochemistry 2009年第1期28卷 19-27页

作者： ukaegbu V.u. Beka F.T. Department of Geology University of Port Harcourt Port Harcourt Nigeria

A model for the petrogenetic affinity and original geotectonic setting of ortho-amphibolites from the Obudu Plateau was tested using the distribution patterns of trace and rare-earth elements from the geochemical analyses of twelve representative amphibolite samples. Discrimination plots, normalized patterns of the incompatible trace elements against average MORB, low ratios of Ba/Nb (9–23) and Ba/ta (130–327) and other geochemical characteristics suggest that the protoliths were dominantly of tholeiitic MORB composition. The va.ues of the ratios of La/ta (8.13–10.8), Rb/Sr (0.04–0.07), Th/u (mainly 4.43–5.43) and Hf/ta (2.35–2.88) further indicate that the ortho-amphibolites demonstrate E-type MORB characteristics. These fea.ures are related to substantial ocean floor divergent tectonic boundary setting rather than marginal basin tectonic setting. This evolutionary pattern appears to be controlled by limited progressive partial melting and fractional crystallization of a single mantle source region, irrespective, however, of variations due to local source heterogeneities. The tholeiitic magmas were most probably generated by hotspot activities on the constructive plate margins and subsequently modified by subduction-related low-K tholeiitic chemistry due to narrowing of a proto oceanic basin between the West African craton and eastern Sahara plate. A likely model, therefore, is that the amphibolites of the Obudu Plateau represent ophiolitic suites with characteristics of enriched mid-ocean floor tholeiites, which were deformed and metamorphosed during a reversed plate motion involving subduction and collision within the Obudu Plateau in the Pan-African orogenic episode.

关键词： REE 微量元素地面沉陷角闪岩地球化学

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