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Mismatch analysis of all-fiber coherent beam combiners based on the self-imaging effect

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High Power Laser Science and Engineering 2024年第2期12卷 1-15页

作者： Yuefang Yan Yu Liu Haoyu Zhang Yuwei Li Chao Guo Qiang Shu wenhui Huang Feng Jing Rumao Tao Laser Fusion Research Center China Academy of Engineering PhysicsMianyangChina Key Laboratory of Particle&Radiation Imaging(Tsinghua University) Ministry of EducationBeijingChina

All-fiber coherent beam combiners based on the self-imaging effect can achieve a near-perfect single laser beam,which can provide a promising way to overcome the power limitation of a single-fiber *** of the key points is combining efficiency,which is determined by various mismatches during fabrication.A theoretical model has been built,and the mismatch error is analyzed numerically for the first *** mismatch errors have been numerically studied with the beam quality and combining efficiency being chosen as the evaluation *** tolerance of each mismatch error for causing 1%loss is calculated to guide the design of the beam *** simulation results are consistent with the experimental results,which show that the mismatch error of the square-core fiber is the main cause of the efficiency *** results can provide useful guidance for the fabrication of all-fiber coherent beam combiners.

关键词： all-fiber coherent beam combination mismatch analysis self-imaging

西延高铁黄土高边坡稳定性计算及强度反演分析

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地质与勘探 2024年第5期60卷 1054-1065页

作者：赵文辉陕西铁道工程勘察有限公司陕西西安710043

西延高铁沿线发育8000余处滑坡及不稳定高边坡,在项目建设过程中,黄土高边坡已成为重大致灾因素之一,因其造成的滑坡、崩塌等易危害路基、桥梁、隧道口、车站等重要构筑物。通过对铜川至延安段的黄土边坡调绘,选取了72.坡高范围为30~9... 详细信息

西延高铁沿线发育8000余处滑坡及不稳定高边坡,在项目建设过程中,黄土高边坡已成为重大致灾因素之一,因其造成的滑坡、崩塌等易危害路基、桥梁、隧道口、车站等重要构筑物。通过对铜川至延安段的黄土边坡调绘,选取了72.坡高范围为30~90 m的典型黄土高边坡,分区绘制了坡体高度与宽度的拟合方程。基于黄土高边坡稳定性计算方程组,应用Slope/W模块构建断面模型,应用Morgenstern-Price法逐级反演获得极限状态下(稳定系数F_(s)=1.0)高边坡不同坡高对应的综合抗剪强度参数c、φ值。结果表明:边坡高度与粘聚力c成正相关,与内摩擦角φ成负相关,且二者对边坡稳定性的敏感度也不同,低坡时,φ值较高,贡献更加突出;高坡时,c值明显增高,贡献更大。铜黄段与黄延段不同坡高的反演强度参数变化趋势非常相似。但相同坡高范围内,铜黄段的c值普遍高于黄延段15~2. kPa,相对应的φ值低于黄延段1°~5°,这一强度变化规律与黄土在这一区域的成分及其物理性质反映的特点相吻合。并以陕西洛川东咀头滑坡为例,对该反演方法进行了验算,反演获得的抗剪强度参数与实测值较为吻合。

关键词：黄土高边坡抗剪强度极限状态 Slope/W 反演西延高铁

Investigation of the epidemiology,pathogenicity and immunogenicity of Bordetella bronchiseptica isolated from cats and dogs in China from 2.2. to 2.2.

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Animal Diseases 2024年第3期4卷 156-172页

作者： Qinghua Shang wenhui Gao Xiangting Zhang Jianqing Zhao Ying Wu Haoqi Li Ming Zhou Zhen F.Fu Chengguang Zhang Ling Zhao National Key Laboratory of Agricultural Microbiology Huazhong AgriculturalUniversityWuhan 430070China. Key Laboratory of Preventive VeterinaryMedicine of Hubei Province College of Veterinary MedicineHuazhongAgricultural UniversityWuhan 430070China. Hubei Hongshan Laboratory Wuhan 430070China.

Bordetella bronchiseptica(Bb)is recognized as a leading cause of respiratory diseases in dogs and ***,epidemiological data on Bb in dogs and cats in China are still limited,and there is no commercially available *** vaccines containing Bb that are widely used abroad are generally efective but can establish latency and potentially reactivate to cause illness in some immunodefcient vaccinated recipients,raising safety *** this study,34 canine-derived and two feline-derived Bb strains were isolated from 1809 canine and 113 feline nasopharyngeal swab samples collected from eight provinces in China from 2.2. to *** PCR results showed that the percentage of positive Bb was 2..94%(441/192.),and more than 90%of the Bb isolates had four virulence factor-encoding genes(VFGs),namely,fhaB,prn,betA and *** the isolated strains displayed a multidrug-resistant *** virulence of 10 Bb strains isolated from dogs with respiratory symptoms was tested in mice,and we found that eight isolates were highly ***,the eight Bb isolates with high virulence were inactivated and intramuscularly injected into mice,and three Bb strains(WH12.8,WH12.3 and WH12.4)with the best protective efcacy were *** immunized with these three strains exhibited strong protection against challenge with the Bb feld strain ***,the WH12.8 strain with the greatest protection in dogs was selected as the vaccine *** and cats that received a vaccine containing 109 CFU of the inactivated WH12.8 strain showed complete protection against challenge with the Bb feld strain *** study revealed that Bb is an important pathogen that causes respiratory diseases in domestic dogs and cats in China,and all the isolates exhibited multidrug *** present work contributes to the current understanding of the prevalence,antimicrobial resistance,and virulence genes of Bb in domestic dogs and ***,our results suggest

关键词： Bordetella bronchiseptica Epidemiological investigation Pathogenicity Immunogenicity Inactivated vaccine

Microbiome and metabolome dysbiosis analysis in impaired glucose tolerance for the prediction of progression to diabetes mellitus

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Journal of Genetics and Genomics 2024年第1期51卷 75-86页

作者： Boxun Zhang Xuan Zhang Zhen Luo Jixiang Ren Xiaotong Yu Haiyan Zhao Yitian Wang wenhui Zhang Weiwei Tian Xiuxiu Wei Qiyou Ding Haoyu Yang Zishan Jin Xiaolin Tong Jun Wang Linhua Zhao Institute of Metabolic Diseases Guang'anmen HospitalChina Academy of Chinese Medical SciencesBeijing 100053China Faculty of Biological Science and Technology Baotou Teacher's CollegeBaotouInner Mongolia 014030China CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Infinitus(China)Company Ltd GuangzhouGuangdong 510405China Affiliated Hospital of Changchun University of Chinese Medicine ChangchunJilin 130021China Department of Endocrinology Guang'anmen HospitalChina Academy of Chinese Medical SciencesBeijing 100053China Xinjiekou Community Health Service Center in Xicheng District Beijing 100035China Department of Spleen and Stomach Shenzhen Traditional Chinese Medicine HospitalShenzhenGuangdong 518033China University of Chinese Academy of Sciences Beijing 100049China Beijing University of Chinese Medicine Beijing 100105China Northeast Asia Institute of Traditional Chinese Medicine Changchun University of Chinese MedicineChangchunJilin 130117China

Gut microbiota and circulating metabolite dysbiosis predate important pathological changes in glucose metabolic disorders;however,comprehensive studies on impaired glucose tolerance(IGT),a diabetes mellitus(DM)precursor,are ***,we perform metagenomic sequencing and metabolomics on 47 pairs of individuals with IGT and newly diagnosed DM and 46 controls with normal glucose tolerance(NGT);patients with IGT are followed up after 4 years for progression to *** of baseline data reveals significant differences in gut microbiota and serum metabolites among the IGT,DM,and NGT *** addition,13 types of gut microbiota and 17 types of circulating metabolites showed significant differences at baseline before IGT progressed to DM,including higher levels of Eggerthella unclassified,Coprobacillus unclassified,Clostridium ramosum,L-valine,L-norleucine,and L-isoleucine,and lower levels of Eubacterium eligens,Bacteroides faecis,Lachnospiraceae bacterium 3_1_46FAA,Alistipes senegalensis,Megaspaera elsdenii,Clostridium perfringens,α-linolenic acid,10E,12.-octadecadienoic acid,and dodecanoic acid.A random forest model based on differential intestinal microbiota and circulating metabolites can predict the progression from IGT to DM(AUC=0.87).These results suggest that microbiome and metabolome dysbiosis occur in individuals with IGT and have important predictive values and potential for intervention in preventing IGT from progressing to DM.

关键词： Impaired glucose tolerance Diabetes mellitus Gut microbiota Metabolomics

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“对言语法”和中国逻辑

当代修辞学 2024年第4期 2-15页

作者：宋文辉中国人民大学文学院北京100872

“对言语法”揭示了汉语语法的诸多核心特征,说明其依据的是对话逻辑,跟西方基于命题建构的演绎逻辑不同。本文梳理思想史的线索发现,与“对言语法”的认识一致,汉语和印欧语语法根本特征的差别、中西思想传统的差别都是命题是否占据核... 详细信息

“对言语法”揭示了汉语语法的诸多核心特征,说明其依据的是对话逻辑,跟西方基于命题建构的演绎逻辑不同。本文梳理思想史的线索发现,与“对言语法”的认识一致,汉语和印欧语语法根本特征的差别、中西思想传统的差别都是命题是否占据核心地位。西方思想传统以命题和表征论为根本,中国思想传统对此持消极立场,这是双方对“道”与“言”关系看法相左的结果。由此导致中西逻辑有别:中国逻辑重视实际观点的论证和类比推理,西方则将演绎推理视为理性的根本。前者对逻辑陈述的分析简单,后者则重视命题结构和范畴的系统分析。中国逻辑独立形成且具备特质,跟西方、印度逻辑体系三分天下,“对言语法”和对话逻辑继承并发展了上述传统,这是其合理性的重要依据之一。

关键词： “对言语法” 对话逻辑演绎逻辑协同演化

分层系统下的短期利率调控:机理、经验及启示

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金融评论 2024年第2期16卷 135-154,158页

作者：王文汇中国社会科学评价研究院

2.08年国际金融危机驱使全球货币政策框架向流动性过剩条件叠加长期低(负)利率立场转变,继而引发银行间同业拆借市场交易萎缩、机构盈利能力受损等问题。在此背景下,分层系统调控模式应运而生。本文通过构建同业拆借市场准备金需求模型... 详细信息

2.08年国际金融危机驱使全球货币政策框架向流动性过剩条件叠加长期低(负)利率立场转变,继而引发银行间同业拆借市场交易萎缩、机构盈利能力受损等问题。在此背景下,分层系统调控模式应运而生。本文通过构建同业拆借市场准备金需求模型,剖析了不同类型分层系统对短期利率的调控机理;然后在梳理新西兰、丹麦、挪威、欧元区、瑞士和日本政策实践的基础上,探讨了分层系统的主要优势、定位及在我国的应用前景。结果表明,附带分层系统的利率走廊能同时实现引导短期利率、刺激同业拆借市场交易和保护银行盈利的目的,其行之有效的关键在于合理设计惩罚性低利率豁免规则。对于我国而言,尽管当前暂无设立分层系统的必要性,但不妨将其作为应对自然利率长期下行趋势、助力央行数字货币平稳落地的备选之策。本文研究结论可为进一步完善适合我国国情、适应经济高质量发展、适配中国式现代化需要的货币政策框架提供参考。

关键词：分层系统利率走廊货币政策操作流动性管理

面向自动驾驶的公交车辆进出港湾式停靠站安全轨迹模型

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应用基础与工程科学学报 2024年第3期32卷 666-684页

作者：张文会张攀伊静东北林业大学土木与交通学院黑龙江哈尔滨150040

为研究公交车辆安全平稳进出港湾式停靠站的轨迹,提出适用于自动驾驶场景的进出站安全轨迹规划方法.基于阿克曼转向原理,构建车身4个顶点运动轨迹方程,针对站内无车和有车两种工况,建立避障约束、运动学约束及起终点位姿约束,选择五次... 详细信息

为研究公交车辆安全平稳进出港湾式停靠站的轨迹,提出适用于自动驾驶场景的进出站安全轨迹规划方法.基于阿克曼转向原理,构建车身4个顶点运动轨迹方程,针对站内无车和有车两种工况,建立避障约束、运动学约束及起终点位姿约束,选择五次多项式曲线作为公交车辆进出港湾式停靠站安全轨迹模型,采用线性规划和遗传算法标定模型参数,采用数值模拟得到车辆安全进出站轨迹,并利用实车道路实验验证模型的可行性.研究结果表明:五次多项式曲线适用于公交车辆进出港湾式停靠站安全轨迹,规划轨迹与实际运行轨迹平均绝对百分比误差(MAPE)不超过10%,提出的轨迹规划方法可为自动驾驶公交车辆安全可靠运行提供一定的理论依据.

关键词：交通工程公交车辆安全轨迹港湾式停靠站自动驾驶五次多项式遗传算法

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换个视角看2.年来胰腺癌的治疗进展

中华外科杂志 2024年第7期62卷 654-658页

作者：刘亮楼文晖复旦大学附属中山医院胰腺外科上海200032

近2.年来, 胰腺癌的治疗取得长足进步, 多个一线治疗方案如吉西他滨联合厄洛替尼、吉西他滨联合白蛋白紫杉醇、FILFIRINOX、NALIRIFOX等不断涌现;以手术为中心的综合治疗也逐渐成为胰腺癌的临床主流策略。然而在这成绩的背后, 巨额经费... 详细信息

近2.年来, 胰腺癌的治疗取得长足进步, 多个一线治疗方案如吉西他滨联合厄洛替尼、吉西他滨联合白蛋白紫杉醇、FILFIRINOX、NALIRIFOX等不断涌现;以手术为中心的综合治疗也逐渐成为胰腺癌的临床主流策略。然而在这成绩的背后, 巨额经费资助下研发的新药尚未使晚期胰腺癌患者的中位生存时间超过1年;接受根治性手术患者的5年生存率也低于30%。因此, 随着胰腺癌发病率的不断增加, 提高胰腺癌诊治效果的紧迫性已从"任重道远"向"迫在眉睫"转变。研究者在积极进取的同时, 更需要冷静思考, 不断审视前进的方向, 以期给胰腺癌患者带来切实的临床获益。

关键词：胰腺肿瘤肿瘤治疗方案临床治疗

基于端电压尖峰的无刷直流电机无位置传感器换相控制策略

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电机与控制学报 2024年第5期28卷 173-182页

作者：黄文晖闵华松武汉科技大学机器人智能系统研究院湖北武汉430081

针对现有的换相误差补偿方法需要额外滤波电路和检测电路导致无传感器换相方法变得更加复杂的问题,提出一种端电压尖峰脉冲换相误差补偿方法,实现了对无刷直流电机无传感器换相误差的准确补偿。研究了抗干扰性强的端电压尖峰脉冲信号的... 详细信息

针对现有的换相误差补偿方法需要额外滤波电路和检测电路导致无传感器换相方法变得更加复杂的问题,提出一种端电压尖峰脉冲换相误差补偿方法,实现了对无刷直流电机无传感器换相误差的准确补偿。研究了抗干扰性强的端电压尖峰脉冲信号的变化特性,得出了端电压尖峰脉冲持续时间是随着换相误差单调变化的结论,并利用端电压尖峰脉冲设计了换相误差闭环控制方法。该方法无需额外的滤波电路和检测电路,简化了换相误差补偿方法的电路设计,并且具备良好的鲁棒性和准确性。搭建了仿真和实际实验平台,对比了补偿前后的换相误差,实验结果表明,所提出方法能够实现准确的换相误差补偿。仿真实验和实际实验中,换相误差分别被控制在了1.1个电角度范围内和4个电角度范围内。在速度调控实验中,补偿后的无传感器方法表现出了和霍尔传感器相似的动态特性。相比于现有方法,提出方法更适合无刷直流电机无传感器方法在高性能电机控制场景的应用。

关键词：无刷直流电机六步换相法无传感器控制换相误差补偿端电压尖峰脉冲闭环控制

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