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中国EPS泡沫塑料回收利用状况及技术进展 被引量:12
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作者 侯树亭 《塑胶工业》 2006年第5期25-27,共3页
关键词 EPS 技术进展 利用状况 塑料回收 中国 资源化技术 回收利用 泡沫
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Genetic testing vs microforceps biopsy in pancreatic cysts:Systematic review and meta-analysis 被引量:2
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作者 Sandra Faias Luisa Pereira +2 位作者 Angelo Luis Paula Chaves Marilia Cravo 《World Journal of Gastroenterology》 SCIE CAS 2019年第26期3450-3467,共18页
BACKGROUND Carcinoembryonic antigen(CEA)and cytology in pancreatic cystic fluid are suboptimal for evaluation of pancreatic cystic neoplasms.Genetic testing and microforceps biopsy are promising tools for pre-operativ... BACKGROUND Carcinoembryonic antigen(CEA)and cytology in pancreatic cystic fluid are suboptimal for evaluation of pancreatic cystic neoplasms.Genetic testing and microforceps biopsy are promising tools for pre-operative diagnostic improvement but comparative performance of both methods is unknown.AIM To compare the accuracy of genetic testing and microforceps biopsy in pancreatic cysts referred for surgery.METHODS We performed a literature search in Medline,Scopus,and Web of Science for studies evaluating genetic testing of cystic fluid and microforceps biopsy of pancreatic cysts,with endoscopic ultrasound with fine-needle aspiration(EUSFNA)prior to surgery and surgical pathology as reference standard for diagnosis.We evaluated the diagnostic accuracy for:1-benign cysts;2-mucinous low-risk cysts;3-high-risk cysts,and the diagnostic yield and rate of correctly identified cysts with microforceps biopsy and molecular analysis.We also assessed publication bias,heterogeneity,and study quality.RESULTS Eight studies,including 1206 patients,of which 203(17%)referred for surgery who met the inclusion criteria were analyzed in the systematic review,and seven studies were included in the meta-analysis.Genetic testing and microforceps biopsies were identical for diagnosis of benign cysts.Molecular analysis was superior for diagnosis of both low and high-risk mucinous cysts,with sensitivities of 0.89(95%CI:0.79-0.95)and 0.57(95%CI:0.42-0.71),specificities of 0.88(95%CI:0.75-0.95)and 0.88(95%CI:0.80-0.93)and AUC of 0.9555 and 0.92,respectively.The diagnostic yield was higher in microforceps biopsies than in genetic analysis(0.73 vs 0.54,respectively)but the rates of correctly identified cysts were identical(0.73 with 95%CI:0.62-0.82 vs 0.71 with 95%CI:0.49-0.86,respectively).CONCLUSION Genetic testing and microforceps biopsies are useful second tests,with identical results in benign pancreatic cysts.Genetic analysis performs better for low-and high-risk cysts but has lower diagnostic yield. 展开更多
关键词 Pancreatic CYSTS ENDOSCOPIC ULTRASOUND ENDOSCOPIC ULTRASOUND with fineneedle ASPIRATION Genetic testing Microforceps BIOPSY Molecular analysis KRAS Carcinoembryonic antigen CYTOLOGY
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P-EPS转向系统噪声分析及改进研究
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作者 张鹏 张维 +1 位作者 丁景峰 邓英奇 《汽车零部件》 2016年第10期68-72,共5页
小齿轮助力式电动助力转向器(P-EPS)因结构设计不合理而产生异响。通过建立机械系统分析模型,利用Artemis Head噪声分析软件对异响产生的原因进行分析,提出了优化设计方案,并对优化设计前后相关零件的结构进行对比。结果表明:优化后的... 小齿轮助力式电动助力转向器(P-EPS)因结构设计不合理而产生异响。通过建立机械系统分析模型,利用Artemis Head噪声分析软件对异响产生的原因进行分析,提出了优化设计方案,并对优化设计前后相关零件的结构进行对比。结果表明:优化后的结构异响得到明显改善,可以应用于同类产品结构设计。 展开更多
关键词 P-EPS 噪声 试验分析 结构优化
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可发性聚苯乙烯EPS树脂国家标准
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《上海包装》 2004年第5期46-47,共2页
本标准规定了可发性聚苯乙烯树脂的产品分类、技术要求、试验方法、检验规则以及标志、包装、运输、储存。
关键词 可发性聚苯乙烯 树脂 EPS 检验规则 储存 试验方法 产品分类 国家标准 规定 标志
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追因溯果:信息资源管理领域因果推断方法的应用与展望
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作者 吴江 陶成煦 +1 位作者 欧桂燕 丁杨 《情报学报》 北大核心 2025年第7期915-932,共18页
推断数据之中的因果关系以揭示信息资源管理现象背后的本质,是信息资源管理领域新的时代命题;探讨信息资源管理领域因果推断方法的应用与展望能够为相关研究提供参考。相较于统计推断,因果推断采用专门的设计与实验控制混淆变量与选择偏... 推断数据之中的因果关系以揭示信息资源管理现象背后的本质,是信息资源管理领域新的时代命题;探讨信息资源管理领域因果推断方法的应用与展望能够为相关研究提供参考。相较于统计推断,因果推断采用专门的设计与实验控制混淆变量与选择偏差,能够更准确地刻画因果关系。就其方法而言,在社会科学领域,潜在结果模型可以灵活应对研究数据的不同特性并揭示复杂社会问题的原因,从而被广泛应用。为此,本文首先从哲学与科学两个层面阐述因果推断的由来;其次,界定因果推断的概念,比较因果推断与统计推断的区别,梳理因果推断的相关术语;再其次,提炼潜在结果模型下信息资源管理领域因果推断方法应用的基本流程,并着重围绕方法的适用条件,分析各类方法在信息资源管理领域的应用思路;最后,针对具体领域,探讨相关研究在方法应用上的现状与不足,在此基础上,从研究方法、应用过程和应用领域三个方面,提出信息资源管理领域因果推断方法应用的前景展望。 展开更多
关键词 信息资源管理 因果推断 潜在结果模型 随机实验 准实验
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Effect of dietary fibre on the gastrointestinal microbiota during critical illness:A scoping review
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作者 Angajendra N Ghosh Calum J Walsh +2 位作者 Matthew J Maiden Tim P Stinear Adam M Deane 《World Journal of Critical Care Medicine》 2025年第1期49-59,共11页
The systemic effects of gastrointestinal(GI)microbiota in health and during chronic diseases is increasingly recognised.Dietary strategies to modulate the GI microbiota during chronic diseases have demonstrated promis... The systemic effects of gastrointestinal(GI)microbiota in health and during chronic diseases is increasingly recognised.Dietary strategies to modulate the GI microbiota during chronic diseases have demonstrated promise.While changes in dietary intake can rapidly change the GI microbiota,the impact of dietary changes during acute critical illness on the microbiota remain uncertain.Dietary fibre is metabolised by carbohydrate-active enzymes and,in health,can alter GI microbiota.The aim of this scoping review was to describe the effects of dietary fibre supplementation in health and disease states,specifically during critical illness.Randomised controlled trials and prospective cohort studies that include adults(>18 years age)and reported changes to GI microbiota as one of the study outcomes using non-culture methods,were identified.Studies show dietary fibres have an impact on faecal microbiota in health and disease.The fibre,inulin,has a marked and specific effect on increasing the abundance of faecal Bifidobacteria.Short chain fatty acids produced by Bifidobacteria have been shown to be beneficial in other patient populations.Very few trials have evaluated the effect of dietary fibre on the GI microbiota during critical illness.More research is necessary to establish optimal fibre type,doses,duration of intervention in critical illness. 展开更多
关键词 Gastrointestinal microbiota Dietary fibre HEALTH Critical illness Short chain fatty acids
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A simple method for automatic recreation of railway horizontal alignments
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作者 Alberte Castro Gerardo Casal +1 位作者 Duarte Santamarina Miguel E.Vázquez‑Méndez 《Railway Engineering Science》 2025年第1期62-78,共17页
This paper deals with the problem of recreating horizontal alignments of existing railway lines.The main objective is to propose a simple method for automatically obtaining optimized recreated alignments located as cl... This paper deals with the problem of recreating horizontal alignments of existing railway lines.The main objective is to propose a simple method for automatically obtaining optimized recreated alignments located as close as possible to an existing one.Based on a previously defined geometric model,two different constrained optimization problems are formulated.The first problem uses only the information provided by a set of points representing the track centerline while the second one also considers additional data about the existing alignment.The proposed methodology consists of a two-stage process in which both problems are solved consecutively using numerical techniques.The main results obtained applying this methodology are presented to show its performance and to prove its practical usefulness:an academic example used to compare with other methods,and a case study of a railway section located in Parga(Spain)in which the geometry of its horizontal alignment is successfully recovered. 展开更多
关键词 Railway horizontal alignment Geometrical model Constrained optimization problem Numerical resolution
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Wideband Polarized Emissions from PSR J1938+2213
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作者 Shu Ma De-Hua Wang +3 位作者 Shuang-Qiang Wang Fei-Fei Kou Sheng-Nan Sun Na Wang 《Research in Astronomy and Astrophysics》 2025年第8期243-250,共8页
We present a wideband polarization analysis of the mode-changing pulsar PSR J1938+2213 using the ultra-wideband low-frequency receiver on Murriyang,the Parkes 64 m radio telescope.Polarization profiles for both the bu... We present a wideband polarization analysis of the mode-changing pulsar PSR J1938+2213 using the ultra-wideband low-frequency receiver on Murriyang,the Parkes 64 m radio telescope.Polarization profiles for both the burst and weak emission modes are obtained.We find that the pulse widths of the two modes exhibit distinct frequency dependencies:the pulse width increases with frequency in the burst mode,but decreases in the weak mode.The linear and circular polarization fractions also show different trends with frequency between the two modes.Our spectral analysis shows that both modes follow power-law spectra,but with differing spectral indices. 展开更多
关键词 (stars:)pulsars:general stars:neutron methods:data analysis
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Classification of Cyber Threat Detection Techniques for Next-Generation Cyber Defense via Hesitant Bipolar Fuzzy Frank Information
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作者 Hafiz Muhammad Waqas Tahir Mahmood +2 位作者 Walid Emam Ubaid ur Rehman Dragan Pamucar 《Computers, Materials & Continua》 2025年第9期4699-4727,共29页
Cyber threat detection is a crucial aspect of contemporary cybersecurity due to the depth and complexity of cyberattacks.It is the identification of malicious activity,unauthorized access,and possible intrusions in ne... Cyber threat detection is a crucial aspect of contemporary cybersecurity due to the depth and complexity of cyberattacks.It is the identification of malicious activity,unauthorized access,and possible intrusions in networks and systems.Modern detection methods employ artificial intelligence and machine learning to study vast amounts of data,learn patterns,and anticipate potential threats.Real-time monitoring and anomaly detection improve the capacity to react to changing threats more rapidly.Cyber threat detection systems aim to reduce false positives and provide complete coverage against the broadest possible attacks.This research advocates for proactive measures and adaptive technologies in defending digital environments.Improvements in detection ability by organizations will assist in safeguarding assets and integrity in operations in this increasingly digital world.This paper draws on the categorization of cyber threat detection methods using hesitant bipolar fuzzy Frank operators.Categorization is a step that is necessary for systematic comparison and assessment of detection methods so that the most suitable method for particular cybersecurity requirements is chosen.Furthermore,this research manages uncertainty and vagueness that exists in decision-making by applying hesitant bipolar fuzzy logic.The importance of the work lies in how it fortifies cybersecurity architectures with a formal method of discovering optimal detection measures and improving responsiveness,resulting in holistic protection against dynamic threats. 展开更多
关键词 CYBERSECURITY threat detection hesitant bipolar fuzzy sets frank operators MCDM process
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Strive to thrive-an international partnership for developing an outcome-based curriculum for cataract surgery training by simulation
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作者 Helena Prior Filipe Karl Golnik +1 位作者 Amelia Buque Mathys Labuschagne 《Annals of Eye Science》 2025年第3期24-34,共11页
Background:Health professions education(HPE)in underserved and resource-constrained regions faces persistent challenges,including limited faculty development opportunities and the absence of context-specific curricula... Background:Health professions education(HPE)in underserved and resource-constrained regions faces persistent challenges,including limited faculty development opportunities and the absence of context-specific curricula.The growing need to increase access to cataract surgery and reduce avoidable blindness underscores the urgency of training more competent cataract surgeons.Developing a standardized,nationally endorsed,outcome-based curriculum for simulation-based training in cataract surgery represents a strategic solution.This study explores integrating online active and constructivist social learning strategies within team projects to address these educational gaps,emphasizing equitable international partnerships between experienced global ophthalmological societies(GOS)in HPE,and national ophthalmological societies(NOS)especially in underserved regions.Methods:We conducted an non-experimental investigation involving the Mozambican College of Ophthalmology(NOS),comprising ten senior ophthalmologist educators,including the President(A.B.),each with over ten years of postgraduate teaching leadership experience.To promote inclusivity and foster future leadership,six early-career ophthalmologists with under five years of experience were invited to join.The GOS was represented by two ophthalmologist educators(K.G.and H.P.F.)affiliated with the Ophthalmology Foundation and experienced in international HPE.Together,both organizations formed an equitable and culturally adapted partnership,led by the NOS,to co-design an outcome-based curriculum for cataract surgery simulation training.The collaborative process used a group mentor-facilitated model integrating design thinking,and social constructivist strategies.A virtual community of practice(vCoP),sustained through WhatsApp,enabled continuous peer support and knowledge exchange.The project spanned eight monthly 90-minute videoconferences via Zoom,incorporating online group mentoring and a virtual jigsaw exercise.Results:The collaboration resulted in the development of a competency-based,simulation-enhanced small incision cataract surgery curriculum structured around the Ophthalmic Simulated Surgical Competency Assessment Rubric(Sim-OSSCAR).The curriculum followed Kern’s six-step framework and was organized into four modular components covering the full range of surgical steps.The vCoP emerged as a key platform for sustained faculty development,collaborative problem-solving,and shared expertise,enhancing institutional capacity within the NOS.Participants anecdotally reported increased confidence in curriculum design,strengthened mentoring relationships,and greater engagement through active learning methodologies.The model demonstrated scalability and adaptability,indicating potential for broader application across other medical specialties and contexts.Conclusions:This study highlights the transformative potential of combining design thinking,active and social learning strategies,and digital tools in HPE.By fostering equitable,structured international collaborations,this approach supports sustainable faculty development and contextually relevant educational innovation.The creation of a dynamic vCoP was instrumental in promoting shared ownership and collaboration,ultimately advancing competency-based,simulation-enhanced training in ophthalmology.These findings suggest similar team-based,technology-enabled strategies could strengthen training and patient care in other underserved settings and with other disciplines. 展开更多
关键词 Simulation-based education(SBE) cataract surgery training international partnership group-mentoring innovative online education
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First Search for Pulsed CH Maser Emission Stimulated by a Pulsar
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作者 Mengting Liu Di Li +6 位作者 J.R.Dawson Joel M.Weisberg George Hobbs Ningyu Tang Gan Luo Duo Xu Donghui Quan 《Research in Astronomy and Astrophysics》 2025年第2期60-69,共10页
We present the first search for pulsed CH maser emission potentially stimulated by PSR J1644-4559,conducted using the ultra-wide-bandwidth low-frequency receiver on Murriyang,CSIRO's Parkes Radio Telescope.Observa... We present the first search for pulsed CH maser emission potentially stimulated by PSR J1644-4559,conducted using the ultra-wide-bandwidth low-frequency receiver on Murriyang,CSIRO's Parkes Radio Telescope.Observations targeted three CHΛ-doublet transitions at 3264,3335,and 3349 MHz,with a variability timescale of78 ms.We detected ten CH emission features at 3335 and 3349 MHz,and seven features at 3264 MHz,during both pulsar-ON and pulsar-OFF phases.The observed velocities align with the OH emission and absorption reported by a previous study,suggesting a close spatial association between CH and OH molecules.The derived column densities for CH clouds within the Parkes beam range from 0.05 to 9.8×10^(13)cm^(-2),indicating that these clouds are likely in diffuse and translucent states.Upper limits for CH column densities within the pulsar beam ranged from 0.3 to 9.8×10^(13)cm^(-2).Comparison of these column densities suggests that CH clouds may exhibit clumpiness and substructure.No significant stimulated emission feature was detected in the optical depth spectra.Additionally,as part of our search for pulsed stimulated emission,we investigated the potential CH absorption of the pulsar signal and found none,in agreement with astrophysical expectations.The upper limits for the potential maser amplification factors towards PSR J1644-4559 at 3264,3335,and 3349 MHz are 1.014,1.009,and 1.009,respectively.This study demonstrates the feasibility of detecting pulsed CH maser emission in the interstellar medium stimulated by pulsar photons. 展开更多
关键词 ISM:molecules (stars:)pulsars:general MASERS
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生态红线区管理:英国科研专用区的历史脉络与经验借鉴 被引量:9
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作者 夏方舟 吴頔 严金明 《地域研究与开发》 CSSCI CSCD 北大核心 2017年第1期143-147,180,共6页
作为关键生态保护区域边界线,生态红线划定当前已经上升为中国国家层面战略部署,然而当前生态红线的研究尚处于探索阶段,对于如何针对红线区域具体设计法规保障、制定管理规则、限定开发行为等方面的研究较为匮乏。鉴于英国已经较为成... 作为关键生态保护区域边界线,生态红线划定当前已经上升为中国国家层面战略部署,然而当前生态红线的研究尚处于探索阶段,对于如何针对红线区域具体设计法规保障、制定管理规则、限定开发行为等方面的研究较为匮乏。鉴于英国已经较为成熟的科研专用区相关保护管理的历史经验,梳理和定位了英国科研专用区的3个发展阶段,探讨了各个发展阶段的基本原则、管理机制和实施保障的演变过程,总结英国科研专用区的规划与管理经验,提出了完善法律保障与规程规范、实施统一监管和区域统筹、并行生态补偿与保护自住、签订标准化管理协议、加强公众参与与研讨机制、提升资金保障与使用效率等对我国生态红线区管理与保障的有益借鉴。 展开更多
关键词 科研专用区 生态红线区 管理协议 历史经验 英国
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国际铁路标准发展趋势与建议 被引量:8
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作者 井国庆 张红平 +1 位作者 王浩宇 王创 《铁道工程学报》 EI 北大核心 2022年第11期100-105,共6页
研究目的:根据近十年国际铁路标准组织机构如国际铁路联盟、国际标准协会以及欧盟标准委员会调研,通过对相关铁路标准制订、发展动态、趋势进行梳理,包括铁路的国际标准组织机构流程、框架和国内合作,总结了部分国内单位参与国际标准的... 研究目的:根据近十年国际铁路标准组织机构如国际铁路联盟、国际标准协会以及欧盟标准委员会调研,通过对相关铁路标准制订、发展动态、趋势进行梳理,包括铁路的国际标准组织机构流程、框架和国内合作,总结了部分国内单位参与国际标准的经验,为今后我国铁路标准“走出去”竞争与合作提供对策与建议,为“一带一路”高标准推动奠定基础。研究结论:(1)我国应积极主导和参与相关国际标准规范制定以提高国际影响力与话语权;(2)有必要早规划、早部署建立“一带一路”铁路互联互通系统,提升国内标准在国际化规则下的适应性与影响力;(3)通过研讨会、培训班、访谈等形式增进交流与认知,为下一步我国主导国际标准提供策略参考;(4)科研院校和企业应促进国际铁路标准培育体系优化,提高我国铁路国际业务综合业务水平,增进相关人才的培养与储备;(5)本文研究结果对中国铁路走出去和“一带一路”沿线国家铁路项目标准化建设有一定指导意义。 展开更多
关键词 铁路 标准 一带一路 国际铁路联盟
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混合动力汽车用永磁式电气变速器的构建(英文) 被引量:2
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作者 程远 Christophe ESPANET +2 位作者 Rochdi TRIGUI Alain BOUSCAYROL 崔淑梅 《汽车安全与节能学报》 CAS 2011年第4期351-355,共5页
提出了一种用于混合动力汽车(HEV)动力传动系统的新型结构的永磁式电气变速器(PM-EVT)。PM-EVT是一种与Toyota Prius混合动力汽车功能相似的串并联HEV传动系统,但是功能更加集成,结构更加简单,省去了用于功率分配的行星齿轮机构。分析了... 提出了一种用于混合动力汽车(HEV)动力传动系统的新型结构的永磁式电气变速器(PM-EVT)。PM-EVT是一种与Toyota Prius混合动力汽车功能相似的串并联HEV传动系统,但是功能更加集成,结构更加简单,省去了用于功率分配的行星齿轮机构。分析了PM-EVT的4种可能的机械结构组合和永磁体配置,并选择其中最简单的一种作为最终方案:具有一个外定子、一个内转子、一个外转子;外定子和内转子分别有独立的三相绕组;永磁体分布在外转子上。分析结果表明:不同的永磁体配置形式具有不同的电机性能和控制性能。 展开更多
关键词 混合动力电动汽车(HEV) 电气变速器(EVT) 永磁电机
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希望修订“65号文件”部分规定
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作者 侯树亭 《城市住宅》 2011年第5期41-41,共1页
65号文的出台在各相关行业内产生连锁反应.针对此情况.EPS专委会形成几点行业意见,希望上级主管单位从我国外墙保温与防火安全的实际情况出发,对65号文中的部分规定进行修订。
关键词 修订 文件 连锁反应 防火安全 外墙保温 EPS 行业
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电动助力转向系统及其关键技术 被引量:11
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作者 周廷明 刘志辉 +2 位作者 李梦奇 陈志刚 唐宁 《机床与液压》 北大核心 2012年第7期176-179,209,共5页
电动助力转向(EPS)系统具有结构简单、节能环保等独特优势得以迅速发展;介绍了EPS的工作原理及分类,分析了EPS系统的助力电机、减速机构、传感器、ECU等关键部件及助力特性、控制理论等关键技术。
关键词 电动助力转向 关键部件 助力特性 控制技术
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基于颗粒流的高填黄土减载明洞土拱效应分析 被引量:7
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作者 姚玉相 李盛 +3 位作者 马莉 王焕 于本田 王长丹 《铁道科学与工程学报》 CAS CSCD 北大核心 2020年第1期139-147,共9页
实际工程表明,在高填方明洞顶部铺设EPS板可以明显降低洞顶竖向土压力,然而,铺设EPS板会将明洞上方的土体荷载向其两侧土体转移,导致其侧墙所受水平土压力及弯矩增大。为了进一步减小明洞受力,提出一种新型减载明洞体系,利用颗粒流软件... 实际工程表明,在高填方明洞顶部铺设EPS板可以明显降低洞顶竖向土压力,然而,铺设EPS板会将明洞上方的土体荷载向其两侧土体转移,导致其侧墙所受水平土压力及弯矩增大。为了进一步减小明洞受力,提出一种新型减载明洞体系,利用颗粒流软件建立相应数值模型,从竖向、水平土压力、颗粒竖向位移、颗粒间接触力和孔隙率等细观层面研究该减载明洞的荷载传递机制。此外,基于该减载体系,分析EPS板距拱顶位置、宽度和填土压实度对明洞土拱效应的影响。研究结果表明:该减载体系可以扩大土拱效应的影响范围,同时减小洞顶与洞侧土压力;土拱效应的发展与洞顶土体孔隙率的变化相关,孔隙率随EPS板距拱顶距离的增加逐渐减小,土拱效应逐渐减弱,洞顶土压力逐渐增大;随EPS板宽度的增加先增大后减小,当EPS板宽度W=1.5D时,孔隙率达到最大值,土拱效应最强,洞顶荷载分布最少;填土压实度越大,柱土应力比越大,洞顶土压力越小。 展开更多
关键词 新型减载明洞体系 颗粒流 土拱效应 微观
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欧洲迷迭香的研究状况 被引量:50
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作者 Rosemary Cole 毕良武 赵振东 《生物质化学工程》 CAS 2006年第2期41-44,共4页
综述了迷迭香在欧洲特别是英国、法国、德国、西班牙、意大利和瑞士等国的发展状况,内容涉及迷迭香的科研、标准、种植、加工、应用和贸易等方面情况。
关键词 迷迭香 欧洲 发展状况
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FAST 19波束脉冲星漂移扫描巡天模拟 被引量:9
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作者 刘鹏 王培 +6 位作者 李菂 张洁 张蕾 张承民 朱炜炜 岳友岭 代实 《天文学进展》 CSCD 北大核心 2018年第2期173-188,共16页
脉冲星搜索是500 m口径球面射电望远镜(Five-hundred-meter Aperture Spherical Radio Telescope,FAST)的主要科学目标之一。针对FAST设备性能,模拟FAST脉冲星巡天,优化巡天方案,对即将开展的FAST脉冲星巡天项目具有重要的实用价值。基... 脉冲星搜索是500 m口径球面射电望远镜(Five-hundred-meter Aperture Spherical Radio Telescope,FAST)的主要科学目标之一。针对FAST设备性能,模拟FAST脉冲星巡天,优化巡天方案,对即将开展的FAST脉冲星巡天项目具有重要的实用价值。基于Parkes多波束巡天、Parkes中纬度巡天和Parkes高纬度巡天的结果,利用脉冲星分布模拟软件包PsrPopPy,模拟得到了银河系中正常脉冲星和毫秒脉冲星的空间分布样本,并根据FAST设备参数进行了虚拟观测。结果表明,使用FAST 19波束接收机漂移扫描观测模式,在中心频率为1250MHz,带宽为400 MHz,每波束扫描时间为13.5 s,有效积分时间为6.0 s的情况下,在赤纬为-14~?12′~65~?48′天区内,可发现1600颗正常脉冲星和238颗毫秒脉冲星。为获得银河系中脉冲星自旋演化的样本,使用evolve代码进行了再次模拟。设置相同的观测参数的情况下,在全天范围内模拟探测到孤立正常脉冲星1749颗,并得到其在P-P图上的分布。 展开更多
关键词 FAST 脉冲星 脉冲星模拟 脉冲星巡天模拟
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从自治到共治:制度变迁视角下苏州传统村落空间治理逻辑 被引量:6
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作者 周敏 王勇 李广斌 《人文地理》 CSSCI 北大核心 2024年第5期72-82,共11页
治理有效是国家乡村振兴战略目标实现的重要基础,制度是影响传统村落空间保护治理的基本要素。基于制度变迁理论视角,采取史料搜集、田野调查、深度访谈等研究方法,通过回溯苏州传统村落保护治理实践,揭示传统村落“制度变迁—治理转变... 治理有效是国家乡村振兴战略目标实现的重要基础,制度是影响传统村落空间保护治理的基本要素。基于制度变迁理论视角,采取史料搜集、田野调查、深度访谈等研究方法,通过回溯苏州传统村落保护治理实践,揭示传统村落“制度变迁—治理转变”阶段演进特征及其空间治理效应。结果表明:(1)传统村落保护实践经历了“单向传导—双向并行—双向互馈”三个制度变迁阶段,并依次按照“一元自治—二元并治—多元共治”治理逻辑衍化。(2)在“制度变迁—治理转变”的作用路径下,苏州传统村落空间治理按照“空间资源保护—空间环境整治—空间功能更新”价值逻辑进阶。(3)应着力推动正式性与非正式性制度双向融合、内源式与外源式相结合的柔性化共治模式转型及其制度创新,以实现乡村振兴战略目标下传统村落的善治。 展开更多
关键词 制度变迁 传统村落 空间治理 苏州
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