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不同轨道不平顺激励下线形关键点处列车走行性分析

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石家庄铁道大学学报（自然科学版） 2024年第1期37卷 74-80页

作者：李帅李向国王凯戴汀石家庄铁道大学道路与铁道工程安全保障省部共建教育部重点实验室河北石家庄050043 石家庄铁道大学土木工程学院河北石家庄050043

为探究不同轨道不平顺激励下,列车以更高速度经过缓圆点(HY)、曲中点(QZ)和圆缓点(YH)时,曲线超高、平面圆曲线半径及缓和曲线长度与列车速度之间的匹配关系,以中国某高速动车组为原型,建立了具有50个自由度的车-线动力学分析模型.研究... 详细信息

为探究不同轨道不平顺激励下,列车以更高速度经过缓圆点(HY)、曲中点(QZ)和圆缓点(YH)时,曲线超高、平面圆曲线半径及缓和曲线长度与列车速度之间的匹配关系,以中国某高速动车组为原型,建立了具有50个自由度的车-线动力学分析模型.研究结果表明,中国无砟轨道谱和德国低干扰谱对于列车在道路线形关键点处的动力响应随列车行驶速度和平面线形参数变化的趋势大致相同,但各关键点之间的响应程度不同;超高和圆曲线半径的变化对于列车动力响应的影响程度较缓和曲线长度大.研究结果可为高铁列车更高速度运行时的线路设计及线路平面参数之间的匹配关系提供一定的理论参考.

关键词：高速铁路轨道不平顺谱线路关键点线路平面参数动力学仿真

钢塔桅结构与天馈线系统检测设计加固维护一体化模式标准及应用

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广播与电视技术 2024年第5期51卷 93-97页

作者：张黎陈才张力常德陈卡塔桅安全科技有限公司北京100045

随着广播、电视以及通讯事业的不断发展,钢塔桅结构及其上架设的天馈线设备得到越来越广泛的关注,广播电视发射塔钢塔桅结构和天馈线系统整体可靠性成为保障安全播出的重要基石。提高钢塔桅安全冗余度,保证天馈线系统正常运行,“检测、... 详细信息

随着广播、电视以及通讯事业的不断发展,钢塔桅结构及其上架设的天馈线设备得到越来越广泛的关注,广播电视发射塔钢塔桅结构和天馈线系统整体可靠性成为保障安全播出的重要基石。提高钢塔桅安全冗余度,保证天馈线系统正常运行,“检测、设计、加固维护一体化”是有效预防、解决安全播出事故的重要举措,三个环节相辅相成,缺一不可,传统的“分部实施、单项解决”已不再适用,“检测、设计、加固维护一体化”将成为管理模式的必然趋势。本文以工程案例为基础,详细探究广播电视发射塔“检测、设计、加固维护一体化”应用过程,总结应用要点,验证加固改造方案的可靠性,为今后类似项目的实施提供了参考。

关键词：钢塔桅天馈线一体化 Midas模型

Coordinated Control of DFIG Converters to Comply with Reactive Current Requirements in Emerging Grid Codes

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Journal of Modern Power systems and Clean Energy 2022年第2期10卷 502-514页

作者： Yuanzhu Chang Ilhan Kocar Jiabing Hu Ulas karaagac ka Wing Chan Jean Mahseredjian the Electrical Engineering Department Polytechnique MontrealMontrealCanada the school of Electrical and Electronic Engineering Huazhong University of Science and TechnologyWuhan 430074China the Department of Electrical Engineering The Hong Kong Polytechnic UniversityHong KongChina

The doubly-fed induction generator(DFIG)is considered to provide a low-reactance path in the negative-sequence system and naturally comply with requirements on the negative-sequence reactive current in emerging grid *** paper shows otherwise and how the control strategy of converters plays a key role in the formation of the active and reactive current *** investigating the existing control strategies from the perspective of grid code compliance and showing how they fail in addressing emerging requirements on the negative-sequence reactive current,we propose a new coordinated control strategy that complies with reactive current requirements in grid codes in the positive-and negative-sequence *** proposed method fully takes advantage of the current and voltage capacities of both the rotor-side converter(RsC)and grid-side converter(GsC),which enables the grid code compliance of the DFIG under unbalanced three-phase voltages due to asymmetrical *** mathematical investigations and proposed strategy are validated with detailed simulation models using the Electric Power Research Institute(EPRI)benchmark *** derived mathematical expressions provide analytical clarifications on the response of the DFIG in the negative-sequence system from the grid perspective.

关键词： Doubly-fed induction generator(DFIG) negative sequence short circuit wind turbine generator reactive current space vector unbalanced fault phase lock loop(PLL).

Promoting Entrepreneurship and Innovation in China:Enhancing Research and Transforming University Curriculum

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Frontiers of Education in China 2013年第2期8卷 173-197页

作者： ka Ho MOK kaN Yue College of Education Zhejiang UniversityHangzhou 310007China Department of Asian and Policy studies The Hong Kong Institute of EducationHong KongChina

In the last three decades or so,China has managed to become the second largest economy in the world,especially after engaging in economic reforms since the late *** being a“world factory”and playing a very significant role in manufacturing products and exporting to different parts of the globe,the Chinese government has realized that depending upon this production mode cannot sustain the country’s long term economic growth and ***,the Chinese government has tried to invest more in advancing technology,research and innovation,knowledge transfer,and promoting entrepreneurship *** article sets out to critically examine the major strategies and policies that the Chinese government has adopted in promoting entrepreneurship and innovation against the wider policies outlined above,with a focused reflection given to the major challenges facing Chinese universities during the process of promoting entrepreneurship and innovation,and entrepreneurship education.

关键词： entrepreneurship education promotion of innovation higher education China

Acute-on-chronic liver failure：recent update

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The Journal of Biomedical Research 2017年第4期31卷 283-300页

作者： Azeem Alam ka Chun suen Daqing Ma Anaesthetics Pain Medicine and Intensive Care Department of Surgery and Cancer Faculty of Medicine Imperial College London Chelsea & Westminster Hospital London SW7 2AZ UK

Acute on chronic liver failure（ACLF） was first described in 1995 as a clinical syndrome distinct to classic acute *** by complications of decompensation,ACLF occurs on a background of chronic liver dysfunction and is associated with high rates of organ failure and significant short-term mortality estimated between45%and 90%.Despite the clinical relevance of the condition,it still remains largely undefined with continued disagreement regarding its precise etiological factors,clinical course,prognostic criteria and management *** is concerning that,despite our relative lack of understanding of the condition,the burden of ACLF among cirrhotic patients remains significant with an estimated prevalence of 30.9%.This paper highlights our current understanding of ACLF,including its etiology,diagnostic and prognostic criteria and *** is evident that further refinement of the ACLF classification system is required in order to detect high-risk patients and improve short-term mortality *** field of metabolomics certainly warrants investigation to enhance diagnostic and prognostic parameters,while the use of granulocyte-colony stimulating factor is a promising future therapeutic intervention for patients with ACLF.

关键词： acute liver failure acute decompensation of cirrhosis hepatorenal syndrome chronic hepatic encephalopathy systemic inflammation

新疆生产建设兵团人间布鲁氏菌病流行特征分析及发病趋势预测

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中国人兽共患病学报 2024年第3期40卷 276-282页

作者：范奔马晓玲杨柳根赵倩王童敏李凡卡石河子大学医学院预防医学系石河子832000 新疆生产建设兵团疾病预防控制中心乌鲁木齐830002

目的分析新疆生产建设兵团2010-2022年布病流行特征,建立Holt-Winters乘法模型(Holt-Winters smoothing,HWs)并预测后期布病发病趋势,为制定布病防治措施提供参考依据。方法收集“中国疾病预防控制信息系统”的传染病报告信息管理系统... 详细信息

目的分析新疆生产建设兵团2010-2022年布病流行特征,建立Holt-Winters乘法模型(Holt-Winters smoothing,HWs)并预测后期布病发病趋势,为制定布病防治措施提供参考依据。方法收集“中国疾病预防控制信息系统”的传染病报告信息管理系统中的兵团2010-2022年布病发病数据,采用描述性流行病学方法分析兵团2010-2022年布病流行特征;运用python 3.7软件建立Holt-Winters模型并预测兵团2022-2024年布病月发病数。结果兵团2010-2022年共报告布病病例6278例,年均报告发病率为16.68/10万,整体呈现上升趋势(趋势χ^(2)=44.874,Ps乘法模型预测2022-2024年报告发病数分别为675例、644例和679例,预测模型的R 2=0.78,拟合效果较好。结论近年来,兵团布病发病人数整体仍处于上升阶段,兵团各师应继续加强对于布病的管控。

关键词：布鲁氏菌病新疆生产建设兵团流行特征发病预测

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母体系统性疾病对新生儿唇腭裂发生的影响

中华口腔医学研究杂志（电子版） 2024年第4期18卷 262-268页

作者：陈嘉婷杜美君石冰黄汉尧口腔疾病研究国家重点实验室国家口腔疾病临床医学研究中心四川大学华西口腔医院唇腭裂外科成都610041

唇腭裂是最常见的先天性缺陷之一,其病因复杂,目前被认为是遗传和环境因素共同作用的结果。唇腭裂会导致颌面发育、牙齿发育、语言、饮食和听力等方面的问题,不仅给患儿带来生理和社会心理上的影响,同时增加家庭经济负担。已有大量研究... 详细信息

唇腭裂是最常见的先天性缺陷之一,其病因复杂,目前被认为是遗传和环境因素共同作用的结果。唇腭裂会导致颌面发育、牙齿发育、语言、饮食和听力等方面的问题,不仅给患儿带来生理和社会心理上的影响,同时增加家庭经济负担。已有大量研究明确母体患系统性疾病与后代患唇腭裂的风险密切相关。本文将从糖尿病、高血压、肥胖和系统性红斑狼疮4种系统性疾病及与系统性疾病密切相关的牙周炎入手,综述其与唇腭裂发生的关系及其影响机制的研究进展,为孕期预防和减少唇腭裂的发生提供系统性疾病角度的临床参考依据,避免或尽量减少后代出现先天性唇腭裂的风险。

关键词：唇裂腭裂糖尿病高血压肥胖症红斑狼疮,系统性牙周炎

Geochemistry of sediments from the Lopare Basin(Bosnia and Herzegovina):Implications for Paleoclimate,Paleosalinity,Paleoredox and Provenance

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Acta Geologica sinica(English Edition) 2020年第5期94卷 1591-1618页

作者： AleksandraŠAJNOVIĆ Nenad GRBA Franz NEUBAUER Milica kaŠANIN-GRUBIN Ksenija sTOJANOVIĆ Nenad PETKOVIĆ Branimir JOVANČIĆEVIĆ University of Belgrade Center of ChemistryICTMStudentski trg 12-1611000 BelgradeSerbia University of Novi sad Faculty of SciencesDepartment of ChemistryBiochemistry and Environmental ProtectionTrg Dositeja Obradovica 321000 Novi SadSerbia Paris Lodron University of salzburg Department of Geography and GeologyHellbrunnerstrasse 345020 SalzburgAustria University of Belgrade Faculty of ChemistryStudentski trg 12-1611000 BelgradeSerbia Rio Tinto–Rio sava Exploration Takovska 4511000 BelgradeSerbia

A combined inorganic and organic geochemical study was carried out on marls and mudstones collected from the Lower Miocene Lopare Basin,Bosnia and Herzegovina.A total of 46 samples collected from two boreholes,Pot 1(depth of 193 m)and Pot 3(depth of 344 m),showed that element abundances like boron(B),lithium(Li),strontium(sr),uranium(U),chromium(Cr),nickel(Ni),magnesium(Mg),sodium(Na)and calcium(Ca)are much higher than average than in the upper continental crust(UCC).Chemical composition indicates at least two sources:(i)Mesozoic ophiolites occurring in the north of the investigated area,and(ii)dacito-andesitic pyroclastics(Mesozoic to Cenozoic).Lopare Basin sedimentation was influenced by strong evaporation resulting in a partly hypersaline lake,which formed during a warm climatic period,probably during the Miocene Climatic Optimum.A brief episode of humid climate conditions resulted in the basin fillingup and deposition of felsic sediments enriched in thorium(Th).Organic geochemistry shows that the majority of studied sediments contains predominantly immature to marginally mature algal organic matter(OM).The biomarker patterns are generally in agreement with the geological history of the Lopare Basin and inorganic and mineralogical ***,the molecular distribution of n-alkanes as reliable climatic andδ-MTTC as paleosalinity indicators do not support this conclusion.

关键词： geochemistry provenance analysis paleoenvironmental conditions salinity/hypersalinity biomarker Lopare Basin Bosnia and Herzegovina

Mimotope-based allergen-specific immunotherapy: ready for prime time?

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Cellular & Molecular Immunology 2019年第11期16卷 890-891页

作者： Nicki Y.H.Leung Christine Y.Y.Wai ka Hou Chu Patrick s.C.Leung Department of Paediatrics The Chinese University of Hong KongShatinHong KongChina school of Life sciences The Chinese University of Hong KongShatinHong KongChina Division of Rheumatology/Allergy School of MedicineUniversity of CaliforniaDavisCA 95616USA

INTRODUCTION Allergen-specific immunotherapy(AIT)is a therapeutic strategy to restore the normal immune response by suppressing inflammatory effector cells and inducing regulatory cells specific to the culprit ***,AIT is achieved by administering escalating doses of allergen over a long treatment ***,the use of unmodified allergens for AIT often results in severe anaphylactic side effects,and alternative approaches such as hypoallergens and T-cell epitopes with enhanced safety have been *** use of mimotopes in AIT is a relatively new concept,but earlier proof-ofconcept studies showed promising results for mimotopes,with decent safety profiles and immunomodulatory *** the treatment of cancer with mimotope-based immunotherapy has already been tested in clinical trials2,mimotope-based AIT remains largely in the preclinical ***,we revisit the pros and cons of mimotope-based AIT and describe recent findings concerning the use of mimotopes in AIT.

关键词： immunotherapy doses treatment