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Driving and Braking Control of PM Synchronous Motor Based on Low-resolution Hall Sensor for Battery Electric Vehicle

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Chinese Journal of Mechanical Engineering 2013年第1期26卷 1-10页

作者： GU Jing OUYANG Minggao li Jianqiu LU Dongbin fang Chuan MA Yan State Key Laboratory of Automotive Safety and Energy Tsinghua University

Resolvers are normally employed for rotor positioning in motors for electric vehicles, but resolvers are expensive and vulnerable to vibrations. Hall sensors have the advantages of low cost and high reliability, but the positioning accuracy is low. Motors with Hall sensors are typically controlled by six-step commutation algorithm, which brings high torque ripple. This paper studies the high-performance driving and braking control of the in-wheel permanent magnetic synchronous motor （PMSM） based on low-resolution Hall sensors. Field oriented control （FOC） based on Hall-effect sensors is developed to reduce the torque ripple. The positioning accuracy of the Hall sensors is improved by interpolation between two consecutive Hall signals using the estimated motor speed. The position error from the misalignment of the Hall sensors is compensated by the precise calibration of Hall transition timing. The braking control algorithms based on six-step commutation and FOC are studied. Two variants of the six-step commutation braking control, namely, half-bridge commutation and full-bridge commutation, are discussed and compared, which shows that the full-bridge commutation could better explore the potential of the back electro-motive forces （EMF）, thus can deliver higher efficiency and smaller current ripple. The FOC braking is analyzed with the phasor diagrams. At a given motor speed, the motor turns from the regenerative braking mode into the plug braking mode if the braking torque exceeds a certain limit, which is proportional to the motor speed. Tests in the dynamometer show that a smooth control could be realized by FOC driving control and the highest efficiency and the smallest current ripple could be achieved by FOC braking control, compared to six-step commutation braking control. Therefore, FOC braking is selected as the braking control algorithm for electric vehicles. The proposed research ensures a good motor control performance while maintaining low cost and high r

关键词： battery electric vehicle field oriented control low-resolution Hall sensor regenerative braking plug braking,six-step commutation braking

Gas compression and likely triggered star formation in the infrared bubble N107

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Research in Astronomy and Astrophysics 2018年第10期18卷 49-64页

作者： Hao li Jin-Zeng li Jing-Hua Yuan Ya-fang Huang Zhi-Yuan Ren National Astronomical Observatories Chinese Academy of Sciences School of Astronomy and Space Science University of Chinese Academy of Sciences

The expansion of HII regions can regulate the evolution of their natal clouds and the star for-mation therein. Infrared dust bubbles, which are frequently associated with HII regions, are ideal labora-tories to test whether impulse（s） driven by the expanding bubbles enhances or suppresses star-formation. In this work, we present a comprehensive study of a 20-pc scale infrared bubble N107 to reveal the com- pression of the neutral gas and associated star-forming activities. We obtain column density （NH2） and dust temperature （Tdust） maps via fitting modified blackbodies to multi-band far-infrared Herschel data. The shell structure can be recognized on the column density map. The molecular gas along the rim of N107 fragments into 94 dense clumps at an angular resolution of 18＂. Besides, based on the GliMPSE point source catalog, we have identified 228 young stellar objects （YSOs） which are categorized into 55 Class I objects, 127 Class II objects and 46 transition disks （TDs）. The 94 clumps and 55 Class I type YSOs are mainly distributed along the shell, which may suggest triggered star formation exists in N107. In addition, analysis of NH2 probability density functions （PDFs） helps us reveal the condition of natal clouds. The two lognormal profiles of PDFs suggest that the surrounding molecular gas has been compressed due to expansion of the bubble. This compression may trigger the star formation process. Moreover, we find the shape of the PDFs changed after removing the background. Taken together, this big bubble seems to compress the surrounding gas and strongly regulate star formation therein.

关键词： ISM HII regions - ISM clouds - stars formation - ISM structure - methods observational

miR-155表达与FLT3-ITD^(+)急性髓系白血病细胞系药物敏感性的关系及机制研究

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中国实验血液学杂志 2024年第2期32卷 395-401页

作者：王凌燕江佩芳李佳蒸陈艳欣胡建达福建医科大学附属协和医院血液科福建省血液病学重点实验室福建省血液病研究所福建福州350001 福建医科大学福建福州350001 福建医科大学附属第二医院福建泉州362000 福建医科大学精准医学研究院福建福州350001

目的:研究miR-155的表达与FLT3-ITD^(+)急性髓系白血病细胞系药物敏感性的关系及潜在的调控机制。方法:通过CRISPR/Cas9基因编辑工具在FLT3-ITD^(+)AML细胞系MV411中实现miR-155编码基因敲除,筛选单克隆细胞,PCR及Sanger测序鉴定单克隆... 详细信息

目的:研究miR-155的表达与FLT3-ITD^(+)急性髓系白血病细胞系药物敏感性的关系及潜在的调控机制。方法:通过CRISPR/Cas9基因编辑工具在FLT3-ITD^(+)AML细胞系MV411中实现miR-155编码基因敲除,筛选单克隆细胞,PCR及Sanger测序鉴定单克隆细胞的基因型,实时荧光定量逆转录PCR鉴定成熟miRNA的表达水平。MTT法计算半数抑制率,比较MV411细胞对多柔比星、奎扎替尼以及米哚妥林的药物敏感性。转录组测序分析miR-155敲除后MV411细胞mRNA水平的变化,基因集富集分析获得miR-155敲除后的信号通路的变化水平,Western blot验证信号通路关键分子的表达。结果:通过PCR初筛和Sanger测序获得了4个基因敲除的杂合子和1个基因插入的杂合子。实时荧光定量逆转录PCR结果显示,这些单克隆细胞中成熟miR-155的表达显著低于野生型克隆。MTT结果显示,与野生型相比,miR-155基因敲除后MV411细胞对多种抗FLT3-ITD^(+)AML的药物敏感性有了显著增加。RNA测序显示miR-155敲除后mTOR信号通路和Wnt信号通路受到抑制。Western blot结果显示,信号通路关键分子p-mTOR、Wnt5α、β-catenin的表达下调。结论:miR-155敲除后能显著提升MV411细胞对多柔比星、奎扎替尼和米哚妥林的药物敏感性,这与包括mTOR及Wnt信号通路在内的多条信号通路的抑制有关。

关键词： miR-155 FLT3-ITD+急性髓系白血病多柔比星米哚妥林奎扎替尼

热带太平洋—印度洋洋际交换及其气候效应的观测研究

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地球科学进展 2024年第8期39卷 788-800页

作者：魏泽勋徐腾飞方越王晶秦秉斌胡石建李颖聂珣炜张志祥李志曹智勇马强自然资源部第一海洋研究所山东青岛266061 崂山实验室山东青岛266237 中国科学院海洋研究所山东青岛266071

热带太平洋—印度洋洋际交换(简称洋际交换)主要通过太平洋—印度洋贯穿流实现,包括印尼贯穿流,不仅是印太洋盆间重要的质量、动量和能量通道,也是太平洋和印度洋之间气候异常信号传播的“海洋信号通道”,还是大西洋深层水体进行表层补... 详细信息

热带太平洋—印度洋洋际交换(简称洋际交换)主要通过太平洋—印度洋贯穿流实现,包括印尼贯穿流,不仅是印太洋盆间重要的质量、动量和能量通道,也是太平洋和印度洋之间气候异常信号传播的“海洋信号通道”,还是大西洋深层水体进行表层补偿从而使大洋传送带闭合的关键环节,因此在全球海洋和气候系统中占有重要地位。国内外对洋际交换海域环流和气候的研究极其重视,自20世纪90年代以来,来自不同国家的学者开始开展观测研究。我国学者2007年起在洋际交换的主要海峡通道、源区及出流海域开展现场观测,成为国际上洋际交换观测的主要力量。以国内外学者基于这些观测资料取得的科学认识为主线,围绕洋际交换的多尺度变化、跨尺度和跨海盆相互作用,以及对太平洋和印度洋主要气候模态的调制作用4个方面,对其研究现状、主要进展以及亟待解决的关键科学问题进行梳理,同时,对未来5~10年的攻关重点与目标进行了展望。

关键词：洋际交换海洋观测印尼贯穿流南海分支多尺度变化气候变化

Deposition rate of hafnium crystal bar by iodide process

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Rare Metals 2014年第2期33卷 161-165页

作者： li-Sen Tian Yan-Xi Yin Zhi-fang Hu Hong-lin Jiang Zhong-Qi li li-Jun Wang Division of Rare Metals Materials & Metallurgy General Research Institute for Nonferrous Metals

Single variable and deposition weight methods were adopted in the experiment. The hafnium crystal bar was fabricated by the iodide process. Influence of hafnium filament temperature（K value）, temperature controlling method, types of feed, and the loading methods on the deposition rate were studied. The results show that the K value, temperature control method, types of feed, and the loading methods have obvious effects on the deposition rate of the hafnium crystal bar. The deposition rate increases with the K value rising in the range of certain temperature;the salt bath controlling temperature method could effectively obtain the better deposition rate; the greater the contact areas of the feeds are, the faster the deposition rate ***, the optimal iodide deposition techniques of preparing hafnium crystal bar are as follows： hafnium turnings as feed,molybdenum feed retainer charging, salt bath temperature controlling under the higher K value.

关键词： Iodide process Hafnium Deposition rate

肠道微生物与失眠之间的因果关系——一项两样本孟德尔随机化分析

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现代预防医学 2024年第7期51卷 1153-1160页

作者：郑雅丹李磊李洋夏翠宏黄茂茂胡月李丹胥章彧胥方元王剑雄西南医科大学附属医院康复医学科西南医科大学康复医学系康复医学与工程泸州市重点实验室

目的利用两样本孟德尔随机化方法探讨肠道微生物与失眠之间的因果关系。方法使用了来自Mi BioGen联盟进行的最大的全基因组关联研究荟萃分析的肠道微生物群的汇总统计数据。失眠的汇总统计数据来自全基因组关联研究GWAS：失眠测量。... 详细信息

目的利用两样本孟德尔随机化方法探讨肠道微生物与失眠之间的因果关系。方法使用了来自Mi BioGen联盟进行的最大的全基因组关联研究荟萃分析的肠道微生物群的汇总统计数据。失眠的汇总统计数据来自全基因组关联研究GWAS：失眠测量。采用逆方差加权、MR-Egger、加权中位数、简单众数法和加权众数法来研究肠道微生物群与失眠之间的因果关系。通过一系列敏感性分析来评估结果的稳定性。结果 MR分析显示柔膜菌纲（β=-0.86, OR=0.42,95%CI:0.25～0.71）和未知科（β=-0.86, OR=0.42,95%CI:0.25～0.71）对失眠具有保护作用。此外，本研究还发现了其他14个类群与失眠之间存在潜在因果关系（P<0.05），分别为草酸杆菌科（F=170.153,P=0.034)、马文布赖恩特菌属（F=162.702,P=0.006)、瘤胃球菌UCG002属（F=298.323,P=0.046)、罕见小球菌属（F=198.442,P=0.045)、厌氧棒状菌属（F=222.074,P=0.032)、伽玛变形菌纲（F=91.816,P=0.006)、巴斯德菌目（F=231.141,P=0.010)、巴斯德菌科（F=231.141,P=0.010)、毛螺菌科属（F=138.761,P=0.045)、消化球菌属（F=287.210,P=0.036)、活泼瘤胃球菌属（F=162.913,P=0.031)、多尔属（F=112.086,P=0.049)、解黄酮菌属（F=95.307,P=0.020)及未知属（F=89.189,P=0.001）。未检测到显著的异质性或多效性。结论孟德尔随机化结果显示柔膜菌纲、未知科和其他14个类群与失眠有因果关系。肠道微生物可能成为改善失眠的治疗方法之一。

关键词：肠道微生物失眠孟德尔随机化

Study on the Hydration and Physical Properties of Cement by M18 Polycarboxylate Superplasticizer Modified Graphene Oxide

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Journal of Renewable Materials 2023年第2期11卷 625-641页

作者： Dalong liao Dongxu li Shun Zhou Xiaotao Zhang Ying fang College of Materials Science and Engineering Nanjing Tech UniversityNanjing211816China

Graphene oxide(GO)as a new nano-enhancer in cement-based materials has gained wide ***,GO is easy to aggregate in alkaline cement mortar with poor *** hinders its application in practical infrastructure *** this work,GO-M18 polycarboxylate compound superplasticizer(GM)were obtained by compounding the M18 polycarboxylate superplasticizer with GO solution at different mass *** dispersion of GM in alkaline solution was systematically *** phases and functional groups of GM were characterized by XRD and *** effects of GM on the cement mortar hydration and the formation of microstructure were investigated by measuring the heat of hydration,MIP,TG/DSC,and *** results show that the long-chain structure of the M18 polycarboxylate superplasticizer can increase the interlayer spacing of GO and weaken the force between GO *** modified GO can be uniformly dispersed in the cement *** can accelerate the early hydration process of cement,which can increase the content of Ca(OH)2 and decrease the grain *** can optimize the pore size distribution of cement-based materials,increase the density of harmless and less harmful pores,thereby improving mechanical *** methods can transform traditional cement-based materials into stronger,more durable composites,which prolong the life of cement-based materials and reduce the amount of cement used for later *** provides an idea for achieving sustainability goals in civil engineering.

关键词： Modified graphene oxide cement polycarboxylate superplasticizer hydration properties me-chanical performance

Collusion-Proof Result Inference in Crowdsourcing

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Journal of Computer Science & Technology 2018年第2期33卷 351-365页

作者： Peng-Peng Chen Hai-Long Sun Yi-li fang Jin-Peng Huai State Key Laboratory of Software Development Environment School of Computer Science and Engineering Beihang University Beijing 100191 China Beijing Advanced Innovation Center for Big Data and Brain Computing Beijing 100191 China

In traditional crowdsourcing, workers are expected to provide independent answers to tasks so as to ensure the diversity of answers. However, recent studies show that the crowd is not a collection of independent workers, but instead that workers communicate and collaborate with each other. To pursue more rewards with little effort, some workers may collude to provide repeated answers, which will damage the quality of the aggregated results. Nonetheless, there are few efforts considering the negative impact of collusion on result inference in crowdsourcing. In this paper, we are specially concerned with the Collusion-Proof result inference problem for general crowdsourcing tasks in public platforms. To that end, we design a metric, the worker performance change rate, to identify the colluded answers by computing the difference of the mean worker performance before and after removing the repeated answers. Then we incorporate the collusion detection result into existing result inference methods to guarantee the quality of the aggregated results even with the occurrence of collusion behaviors. With real-world and synthetic datasets, we conducted an extensive set of evaluations of our approach. The experimental results demonstrate the superiority of our approach in comparison with the state-of-the-art methods.

关键词： crowdsourcing quality control collusion collaborative crowdsourcing result inference

Effect of neutrophil CD64 for diagnosing sepsis in emergency department

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World Journal of Emergency Medicine 2020年第2期11卷 79-86页

作者： Wen-peng Yin Jia-bao li Xiao-fang Zheng Le An Huan Shao Chun-sheng li Department of Emergency Medicine Beijing Chao-Yang HospitalCapital Medical UniversityBeijing 100020China

BACKGROUND:The aim of this study is to investigate the diagnostic and prognostic value of neutrophil CD64(nCD64)as a novel biomarker in sepsis ***:One hundred fifty-one adult patients diagnosed with sepsis and 20 age-matched healthy controls were enrolled in the *** with sepsis were further subdivided into a sepsis group and a septic shock ***64 expression,serum procalcitonin(PCT)level,C-reactive protein(CRP)level,and white blood cell(WBC)count were obtained for each patient,and Sequential Organ Failure Assessment(SOFA)scores were ***:nCD64 expression was higher in the sepsis group with confirmed infection than in the control *** receiver operating characteristic(ROC)curve of nCD64 was higher than those of SOFA score,PCT,CRP and WBC for diagnosing *** area under the curve(AUC)of nCD64 combined with SOFA score was the highest for all *** AUC of nCD64 for predicting 28-day mortality in sepsis was signifi cantly higher than those of PCT,CRP,and WBC,but slightly lower than that of SOFA *** AUC of nCD64 or PCT combined with SOFA score was signifi cantly higher than that of any single parameter for predicting 28-day ***:nCD64 expression and SOFA score are valuable parameters for early diagnosis of infection and prognostic evaluation of sepsis patients.

关键词： Neutrophil CD64 Sepsis Sequential Organ Failure Assessment score Procalcitonin Prognosis Biomarker