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A fault-tolerant triple-redundant voice coil motor for direct drive valves:Design, optimization, and experiment

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Chinese Journal of Aeronautics 2013年第4期26卷 1071-1079页

作者： Wu Shuai Jiao Zongxia Yan liang yu Juntao Chen Chin-Yin School of Electrical Engineering and Automation Science Beihang University Taiwan Ocean Research Institute "National"Applied Research Laboratories

A direct drive actuator （DDA） with direct drive valves （DDVs） as the control device is an ideal solution for a flight actuation system. This paper presents a novel triple-redundant voice coil motor （TRVCM） used for redundant DDVs. The TRVCM features electrical/mechanical hybrid triple-redundancy by securing three stators along with three moving coils in the same frame. A permanent magnet （PM） Halbach array is employed in each redundant VCM to simplify the system structure. A back-to-back design between neighborly redundancies is adopted to decouple the magnetic flux linkage. The particle swarm optimization （PSO） method is implemented to optimize design parameters based on the analytical magnetic circuit model. The optimization objective function is defined as the acceleration capacity of the motor to achieve high dynamic performance. The optimal geometric parameters are verified with 3D magnetic field finite element analysis （FEA）. A research prototype has been developed for experimental purpose. The experimental results of magnetic field density and force output show that the proposed TRVCM has great potential of applications in DDA systems.

关键词： Direct drive valve Hydraulic flight control Magnetic field optimization Particle swarm optimization Redundant motor

Molecular Characterization and SNP Markers of the β-purothionin Gene in Einkorn Wheats

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Agricultural Sciences in China 2009年第9期8卷 1019-1027页

作者： LI Jing-qiong ZHENG You-liang WEI yu-ming Triticeae Research Institute Sichuan Agricultural University Ya ＂an 625014 P.R. China Key Laboratory of Crop Genetic Resources and Improvement in Southwest China Ministry of Education/Sichuan Agricultural University Ya＇an 625014 P.R.China

Forty-three gene sequences encoding purothionin were characterized from the three species or subspecies of einkorn wheats. These sequences contained 887 bp, among which 92 SNPs including 29 indel loci were detected, giving an average SNP frequency of one SNP per 9.64 bases. According to these sequences, 5 SNP markers were successfully designed, which were used to mine the variations ofpurothionin genes of 102 einkorn wheat accessions. Based on the 5 detected SNP loci, 102 einkorn wheat accessions could be divided into 21 haplotypes, among which 11 haplotypes contained a single sample. Phylogenetic analysis indicated that the purothionin genes from einkorn wheats were more closely related to those from D genome than B genome. Seven out of the 43 gene sequences were assumed to be pseudogenes by the definition of containing in-frame stop codons and small insertions/deletions leading to frameshift. In the remaining 36 amino acid sequences, the 8 Cys and Tyr-13 loci in the mature thionin domain which played important roles in the biological activities were all conserved, whereas there were some varieties occurred in some other important amino acid residues such as Lys and Arg.

关键词： einkorn wheats purothionin SNP haplotype

Determination of La/CeO_2 content in ilmenite electrode coating

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Rare Metals 2015年第7期34卷 505-509页

作者： Yong-Huan Guo Xi-ying Fan liang Zhang Hui Fan Yi-Jun Xu College of Mechanical and Electrical Engineering Jiangsu Normal University Xuzhou Hongyuan Automation Technology Limited Company

The ilmenite welding electrode has advantages of low cost and excellent welding technological ***, the welding quality is affected adversely by its poor crack *** solve this problem, 12 kinds of rare earths coating formulas were optimized by means of orthogonal test design and curve *** the powders containing La/Ce O2 were extruded into ilmenite welding electrode through screw-type pressing–scribbling *** that, a series of mechanical properties tests were conducted according to national ***, the mechanical properties data were analyzed comprehensively by analyzing variance, boxplot as well as Minitab 3D surface *** results show that compared with the formula without rare earth, the deposited metal’s impact toughness,the lower yield strength, the tensile strength, and the hardness are increased by 54.44 %, 9.25 %, 6.37 %, and4.27 %, *** other words, Electrode 6 with the La/Ce O2 amount of 0.5 %/0.1 % in coating has better mechanical properties.

关键词： Ilmenite-type electrode Lanthanum/cerium oxide Var

2014—2023年湖南省孕产妇死亡变化趋势及影响因素分析

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中国妇幼卫生杂志 2024年第5期15卷 7-11页

作者：梁婷高洁陈小英吴颖岚郭婷婷陈霞湖南省妇幼保健院湖南长沙410008

目的了解2014—2023年湖南省孕产妇死因变化趋势及其影响因素,探讨降低孕产妇死亡的预防措施。方法收集2014—2023年湖南省经过省级评审的孕产妇死亡个案病例资料,回顾性分析湖南省孕产妇死亡整体情况、死因分布及影响死亡的相关因素。... 详细信息

目的了解2014—2023年湖南省孕产妇死因变化趋势及其影响因素,探讨降低孕产妇死亡的预防措施。方法收集2014—2023年湖南省经过省级评审的孕产妇死亡个案病例资料,回顾性分析湖南省孕产妇死亡整体情况、死因分布及影响死亡的相关因素。结果2014—2023年湖南省孕产妇死亡率呈现明显下降趋势,从2014年14.86/10万下降至2023年的χ2趋势5.62/10万,下降幅度为62.18%(χ^(2)_(趋势)=51.312,P<0.001);死亡原因构成中,间接产科原因占56.91%,直接产科原因占43.09%,χ2趋势直接产科原因总体呈现下降趋势(χ^(2)_(趋势)=4.630,P=0.031)。排在前3位的孕产妇死亡原因分别为产科出血(23.09%)、妊娠合并心血管系统疾病(12.50%)和羊水栓塞(11.91%)。孕产妇死亡的关键影响因素在于县级医疗保健机构医务人员的知识技能。结论2014—2023年湖南省孕产妇死亡控制成效显著,但仍需提高产科出血、妊娠合并症和羊水栓塞的救治能力,进一步降低孕产妇死亡率。

关键词：孕产妇死亡率死亡原因影响因素

Application of Bayesian approach to hydrological frequency analysis

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Science China(Technological Sciences) 2011年第5期54卷 1183-1192页

作者： liang ZhongMin LI BinQuan yu ZhongBo CHANG Wen Juan College of Hydrology and Water Resources Hohai University Nanjing 210098 China Department of Geosciences University of Nevada Las Vegas NV 89154 USA

An existing Bayesian flood frequency analysis method is applied to quantile estimation for Pearson type three (P-III) probability distribution. The method couples prior and sample information under the framework of Bayesian formula, and the Markov Chain Monte Carlo (MCMC) sampling approach is used to estimate posterior distributions of parameters. Different from the original sampling algorithm (i.e. the important sampling) used in the existing approach, we use the adaptive metropolis (AM) sampling technique to generate a large number of parameter sets from Bayesian parameter posterior distributions in this paper. Consequently, the sampling distributions for quantiles or the hydrological design values are constructed. The sampling distributions of quantiles are estimated as the Bayesian method can provide not only various kinds of point estimators for quantiles, e.g. the expectation estimator, but also quantitative evaluation on uncertainties of these point estimators. Therefore, the Bayesian method brings more useful information to hydrological frequency analysis. As an example, the flood extreme sample series at a gauge are used to demonstrate the procedure of application.

关键词： Bayesian theory hydrological frequency analysis Markov Chain Monte Carlo prior distribution posterior distribution

Complex Mutation and Weak Selection together Determined the Codon Usage Bias in Bryophyte Mitochondrial Genomes

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Journal of Integrative Plant Biology 2010年第12期52卷 1100-1108页

作者： Bin Wang Jing Liu liang Jin Xue-ying Feng Jian-Qun Chen State Key Laboratory of Pharmaceutical Biotechnology Department of Biology Nanjing University Nanjing 210093 China

Mutation and selection are two major forces causing codon usage biases. How these two forces influence the codon usages in green plant mitochondrial genomes has not been well investigated. In the present study, we surveyed five bryophyte mitochondrial genomes to reveal their codon usage patterns as well as the determining forces. Three interesting findings were made. First, comparing to Chara vulgaris, an algal species sister to all extant land plants, bryophytes have more G, C-ending codon usages in their mitochondrial genes. This is consistent with the generally higher genomic GC content in bryophyte mitochondria, suggesting an increased mutational pressure toward GC. Second, as indicated by Wright＇s Nc-GC3s plot, mutation, not selection, is the major force affecting codon usages of bryophyte mitochondrial genes. However, the real mutational dynamics seem very complex. Context-dependent analysis indicated that nucleotide at the 2nd codon position would slightly affect synonymous codon choices. Finally, in bryophyte mitochondria, tRNA genes would apply a weak selection force to fine-tune the synonymous codon frequencies, as revealed by data of Ser4-Pro-Thr-Val families. In summary, complex mutation and weak selection together determined the codon usages in bryophyte mitochondrial genomes.

关键词： Selection Nucleotide sequence Mutation Genomes Uses Forcing Plants Planting Wells Mitochondria

Outcomes of catheter-directed thrombolysis versus systemic thrombolysis in the treatment of pulmonary embolism: a metaanalysis

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Journal of Geriatric Cardiology 2023年第6期20卷 459-468页

作者： Huang-Tai MIAO ying liang Xiao-ying LI Xiao WANG Hui-Juan ZUO Zhe-Chun ZENG Shao-Ping NIE Center for Coronary Artery Disease Beijing Anzhen HospitalCapital Medical UniversistyBeijingChina Emergency&Critical Care Center Beijing Anzhen HospitalCapital Medical UniversityBeijingChina Department of Health Care for Cadres Beijing Jishuitan HospitalBeijingChina Department of Clinical&Community Cardiovascular Disease Prevention Beijing Institute of Heart Lung and Blood Vessel DiseaseBeijing Anzhen HospitalCapital Medical UniversityBeijingChina

OBJECTIVE To evaluate the safety and efficacy of catheter-directed thrombolysis(CDT)versus systemic thrombolysis(ST)in the treatment of pulmonary embolism(PE).METHODS The Cochrane Library,PubMed,and Embase databases were searched to collect the literature on the comparison of the results of CDT and ST in the treatment of PE from the beginning of their records to May 2020,and meta-analysis was performed by STATA software(version 15.1).Using standardized data-collection forms,the authors screened the studies and independently extracted data,and assessed the quality of the studies using the Newcastle-Ottawa Scale for cohort *** studies that examined the following results were included in the current study:in-hospital mortality,all-cause bleeding rate,gastrointestinal bleeding rate,intracranial hemorrhage rate,the incidence of shock,and hospital length of *** A total of eight articles,with 13,242 participants,involving 3962 participants in the CDT group and 9280 participants in the ST group were *** compared with ST in the treatment of PE can significantly affect in-hospital mortality rate[odds ratio(OR)=0.41,95%CI:0.30–0.56,P<0.05],all-cause bleeding rate(OR=1.20,95%CI:1.04–1.39,P=0.012),gastrointestinal bleeding rate(OR=1.43,95%CI:1.13–1.81,P=0.003),the incidence of shock(OR=0.46,95%CI:0.37–0.57,P<0.05),and hospital length of stay[standard mean difference(SMD)=0.16,95%CI:0.07–0.25,P<0.05].However,there was no significant effect on intracranial hemorrhage rate in patients with PE(OR=0.70,95%CI:0.47–1.03,P=0.070).CONCLUSIONS CDT is a viable alternative to ST in the treatment of PE,as it can significantly reduce in-hospital mortality rate,all-cause bleeding rate,gastrointestinal bleeding rate,and incidence of ***,CDT may prolong hospital length of stay to a certain *** research is needed to evaluate the safety and efficacy of CDT and ST in the treatment of acute PE and other clinical outcomes.

关键词： thrombolysis mortality treatment

人工智能在基于CT灌注原始图像重组头颅CT血管成像的应用

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中国临床医学影像杂志 2024年第4期35卷 277-282页

作者：欧阳颖张宇泽苏茹茹温孟皇黄飚南方医科大学附属广东省人民医院(广东省医学科学院)放射科广东广州510080

目的:探讨利用人工智能软件从CTP原始图像中重组的CTA的临床应用价值。方法:收集临床疑似缺血性脑血管病患者60例,所有患者均进行头颅CT平扫、CTA与CTP检查,将CT灌注原始图像导入脑灌注智能分析系统获得重组CTA(即CTPA)。以常规CTA扫描... 详细信息

目的:探讨利用人工智能软件从CTP原始图像中重组的CTA的临床应用价值。方法:收集临床疑似缺血性脑血管病患者60例,所有患者均进行头颅CT平扫、CTA与CTP检查,将CT灌注原始图像导入脑灌注智能分析系统获得重组CTA(即CTPA)。以常规CTA扫描结果为参照,CTA与CTPA组各分析540个节段血管,采用Kappa检验比较两者图像质量以及脑动脉狭窄显示的一致性。结果:CTPA图像显示脑动脉强化程度、脑动脉细节显示能力、图像噪声及静脉污染等与CTA相似。CTA和CTPA对脑内动脉显示具有很好的一致性,Kw值均大于0.75。共540个节段血管中,仅15个节段的血管存在CTPA与CTA显示不一致的结果。结论:利用AI软件,能够方便、快捷地迅速从CTP灌注原始图像中重组出血管图像,所得CTPA与常规CTA比较,有较好的一致性,能准确显示动脉狭窄和闭塞。

关键词：卒中体层摄影术,X线计算机

Feedback analysis and design of inductive power links driven by Class-E amplifiers with variable coupling coefficients

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第8期11卷 629-636页

作者： Tian-liang YANG Chun-yu ZHAO Da-yue CHEN Institute of Intelligent Mechatronics Research School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University Shanghai 200240 China

The efficiency of inductive power links driven by Class-E amplifiers may deteriorate due to variation in the coupling coefficient when the relative position of the radio frequency (RF) coils *** solve this problem,a new design methodology of power links is presented in this *** aim of the new design is to use the feedback signal,which is a phase difference between the driving signal and the output current of the Class-E amplifier,to adjust the duty cycle and angular frequency of the driving signal to maintain the optimum state of the inductive power link,and to adjust the supply voltage to keep the output power constant when the coupling coefficient of the RF coils *** parameter adjustments with respect to the coupling coefficient and the feedback signal are derived from the design equation of the inductive power *** validate the feedback control rules,a prototype of the inductive power link was constructed,and its performance validated with the coupling coefficient set at 0.2 and a duty cycle of *** experimental results showed that,by adjusting the duty cycle,the angular frequency,and the supply voltage,the power link can be kept in optimal operation with a constant output power when the coupling coefficient changes from 0.2 to 0.1 to 0.25.

关键词： Inductive power link Closed-loop Class-E amplifier High efficient Variable coupling coefficient