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华法林与阿司匹林在社区老年房颤人群中卒中预防作用的对比:随机对照BAFTA(Birmingham老年房颤治疗研究)试验 被引量:21
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作者 Mant J. Hobbs F.R. +1 位作者 Fletcher K. 罗亮 《世界核心医学期刊文摘(心脏病学分册)》 2007年第12期8-9,共2页
背景:抗凝药物降低房颤患者的卒中风险较抗血小板药物更为有效,但是在老年患者中此益处是否超过出血风险的增加尚不清楚。在老年患者中评价与阿司匹林相比华法林是否会降低大范围卒中、动脉栓塞或其他颅内出血的风险。方法:自初级医疗... 背景:抗凝药物降低房颤患者的卒中风险较抗血小板药物更为有效,但是在老年患者中此益处是否超过出血风险的增加尚不清楚。在老年患者中评价与阿司匹林相比华法林是否会降低大范围卒中、动脉栓塞或其他颅内出血的风险。方法:自初级医疗中心纳入973例年龄≥75岁的房颤患者,患者被随机分配接受华法林(目标INR为2~3)或阿司匹林(75mg/d)治疗。 展开更多
关键词 华法林 BAFTA BIRMINGHAM 老年房颤 阿司匹林 乙酰水杨酸
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Conversion of One- to Two-Way Streets in Birmingham, Alabama
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作者 Virginia P. Sisiopiku Jugnu Chemmannur 《Journal of Civil Engineering and Architecture》 2010年第8期27-36,共10页
This paper summarizes the approach, findings and evaluation methodology for a study that investigated the feasibility and potential impacts of street conversion options on traffic operations in downtown Birmingham, A... This paper summarizes the approach, findings and evaluation methodology for a study that investigated the feasibility and potential impacts of street conversion options on traffic operations in downtown Birmingham, Alabama. Of particular interest were issues related to conversion of grid systems from one-way to two-way operations. Recommendations on the most promising design and control configurations for implementation are also provided. A literature review was performed that threw light on the issues and challenges associated with implementation of street conversions, and the available best practices. A comprehensive traffic impact analysis that ensued employed the SYNCHRO computer simulation model to represent current and future operations so as to assess the implications of two-way conversions at and around the test sites. Detailed realistic two-way operations scenarios were developed that considered geometric and right-of-way restrictions, the location of land uses that generate and/or attract vehicular and pedestrian traffic, connectivity with the street grid, and accessibility to nearby freeway facilities, as well as practical concerns. 展开更多
关键词 Signal optimization one-way operations two-way operations traffic impacts analysis.
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Modeling Freight Truck Trips in Birmingham Using Tour-Based Approach
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作者 Ehsan Doustmohammadi Virginia P. Sisiopiku Andrew Sullivan 《Journal of Transportation Technologies》 2016年第5期436-448,共14页
This research study explores the use of an innovative freight tour-based approach to model truck trips as an alternative to the conventional trip-based approach. The tour-based approach is more realistic as it capture... This research study explores the use of an innovative freight tour-based approach to model truck trips as an alternative to the conventional trip-based approach. The tour-based approach is more realistic as it captures the intermediate stops of each truck and reflects the implications of those stops on vehicle miles traveled (VMT). The paper describes the truck tour-based model concept, and presents the framework of a truck tour-based travel demand forecasting approach. As a case study, Global Positioning System (GPS) truck data are used to determine origin, destination, and truck stops for trucks moving within the Birmingham, Alabama region. Such information is then utilized to model truck movements within the study region as individual truck tours. The tour-based model is ran, and the resulting performance measures are contrasted to those obtained from the conventional trip-based planning model used by the Regional Planning Commission of Greater Birmingham (RPCGB). This case study demonstrates the feasibility of using a tour-based freight demand forecasting model as an alternative to the conventional 4-step process currently used to estimate truck trips in the Birmingham region. The results and lessons learned from the Birmingham case study are expected to improve truck movement modeling practices in the region and advance the accuracy of truck travel demand forecasting models at other locations in the future. 展开更多
关键词 Conventional Freight Demand Forecasting Models Tour-Based Model Truck GPS Data
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Flat Rooftops as Productive Landscapes in Birmingham
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作者 Yangzixian Yang 《Journal of Architectural Research and Development》 2022年第6期53-58,共6页
Due to the changing global environment,sustainable development has become a goal that many cities strive towards.Producing nutritious food is a component of sustainable development.The primary purpose of this paper is... Due to the changing global environment,sustainable development has become a goal that many cities strive towards.Producing nutritious food is a component of sustainable development.The primary purpose of this paper is to assess Birmingham’s suitability for flat rooftop farming.This study explores two examples of rooftop farms:Brooklyn Grange in New York and Thammasat University,the largest rooftop farm in Asia,and they transformed the roof into a productive rooftop farm.This paper proses the tops of the buildings at Birmingham City University to be converted into a flat roof farm with an additional survey into the dietary habits of Birmingham inhabitants.With a productive landscape,one can achieve societal ideals such as urban or communal food self-sufficiency,reduce food imports,transit expenses,and consumer prices,encourage human interaction and connection,and at the same time provide diversified and healthy food. 展开更多
关键词 Sustainable Development Goals(SDGs) Sustainable development Flat rooftop farm Productive landscape Food health level
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Tale of mitochondria and mitochondria-associated ER membrane in patient-derived neuronal models of Wolfram syndrome
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作者 Laetitia Aubry Timothy Barrett Sovan Sarkar 《Neural Regeneration Research》 SCIE CAS 2025年第9期2587-2588,共2页
Mitochondria and mitochondria-associated endoplasmic reticulum membrane in neurodegenerative diseases:Mitochondria generate most of the chemical energy needed to power the biochemical reactions of cells,and thus are o... Mitochondria and mitochondria-associated endoplasmic reticulum membrane in neurodegenerative diseases:Mitochondria generate most of the chemical energy needed to power the biochemical reactions of cells,and thus are often referred to as the"powerhouse"of the cell.Nevertheless,this organelle is also involved in a pleth,ora of different cellular functions such as calcium(Ca^(2+))homeostasis,apoptosis,oxidative stress,and several metabolic pathways including oxidative phosphorylation,tricarboxylic acid cycle,andβ-oxidation of fatty acids. 展开更多
关键词 OXIDATIVE CYCLE carboxylic
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Harnessing therapeutic potential of induced pluripotent stem cell–derived endothelial cells for remyelination in the central nervous system
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作者 Dan Ma Nona Pop 《Neural Regeneration Research》 SCIE CAS 2025年第6期1715-1716,共2页
Myelin is the protective sheath surrounding nerve fibers, and its damage(demyelination) occurs in many central nervous system(CNS) diseases, including multiple sclerosis(MS), traumatic injury, neurodegenerative diseas... Myelin is the protective sheath surrounding nerve fibers, and its damage(demyelination) occurs in many central nervous system(CNS) diseases, including multiple sclerosis(MS), traumatic injury, neurodegenerative diseases such as Alzheimer's disease, and mental disorders such as schizophrenia(Barateiro et al., 2016). Repair of damaged myelin sheaths(remyelination) often fails in MS, leading to neuronal loss and irreversible functional deficits. 展开更多
关键词 MYELIN protective DISEASES
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Vascular endothelial growth factor:a double-edged sword in the development of white matter lesions
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作者 Narek Manukjan Daniel Fulton +2 位作者 Zubair Ahmed WMatthijs Blankesteijn Sébastien Foulquier 《Neural Regeneration Research》 SCIE CAS 2025年第1期191-192,共2页
As the population ages,the burden of age-related diseases becomes greater.Currently,over 55 million people suffer from dementia worldwide,with Alzheimer’s disease being the most common form.However,it is becoming cle... As the population ages,the burden of age-related diseases becomes greater.Currently,over 55 million people suffer from dementia worldwide,with Alzheimer’s disease being the most common form.However,it is becoming clearer that underlying vascular pathology such as cerebral small vessel disease(cSVD)may be a more detrimental cause for dementia(Cuadrado-Godia et al.,2018).It is estimated that 10%-30%of the elderly population and 35%-90%of all dementia patients exhibit signs of cSVD.The term cSVD refers to pathology affecting the small vessels of the brain,which can lead to lacunar cerebral infarcts,enlarged perivascular spaces,and cortical hemorrhages(Cuadrado-Godia et al.,2018).CSVD is often associated with cognitive decline,gait problems,and dementia(Cuadrado-Godia et al.,2018). 展开更多
关键词 PATHOLOGY BECOMING WHITE
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Multilocular thymic cysts-a diagnostic challenge on computed tomography
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作者 Nirmal Kumar Reddy Onteddu Naga Sai Rasagna Mareddy +2 位作者 Sai Swarupa R Vulasala Jayabharath Onteddu Mayur Virarkar 《World Journal of Clinical Cases》 SCIE 2025年第3期61-65,共5页
A recent case report provided a patient scenario,wherein,a 39-year-old male patient presented with occasional palpitations,headache,and fever.Evaluation of tumor markers did not show any abnormal results.Subsequently,... A recent case report provided a patient scenario,wherein,a 39-year-old male patient presented with occasional palpitations,headache,and fever.Evaluation of tumor markers did not show any abnormal results.Subsequently,a computed tomography(CT)scan was undertaken,and its findings were affirmative of thymic cancer.Finally,the postoperative histopathological assessment of the mass,after its resection,confirmed it as an anterior mediastinal multilocular thymic cyst(MTC),with concurrent acute upper respiratory tract infection and acute myocarditis.Accordingly,this case report advocates the need for a preoperative histopathological examination with CT imaging to minimize the risk of confusing an MTC with a malignant thymic tumor. 展开更多
关键词 Imaging findings Multilocular thymic cyst HISTOPATHOLOGY Thymic cancer Mediastinal mass
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Temporal trends in concentrations of legacy and novel brominated flame retardants in house dust from Birmingham in the United Kingdom 被引量:1
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作者 Daniel Simon Drage Sonthinee Waiyarat +2 位作者 Stuart Harrad Mohamed Abou-Elwafa Abdallah Suwanna Kitpati Boontanon 《Emerging Contaminants》 2020年第1期323-329,共7页
Concentrations of polybrominated diphenyl ethers(PBDEs),hexabromocyclododecane(HBCDD),tetrabromobisphenol-A(TBBPA)and two potential replacements decabromodiphenylethane(DBDPE)and 1,2-bis(2,4,6-tribromophenoxy)ethane(B... Concentrations of polybrominated diphenyl ethers(PBDEs),hexabromocyclododecane(HBCDD),tetrabromobisphenol-A(TBBPA)and two potential replacements decabromodiphenylethane(DBDPE)and 1,2-bis(2,4,6-tribromophenoxy)ethane(BTBPE)were measured in dust samples collected from 14 homes across Birmingham(UK).Concentrations were compared with those from the same city in previous studies to ascertain any temporal changes and to assess the effects of legislative restrictions.The average PHBCDDs concentration(46,000 ng/g;median=280 ng/g)included the highest dust concentration recorded globally(570,000 ng/g).This is despite the listing of HBCDD under the Stockholm Convention in 2013,demonstrating that decreases in indoor contamination will likely be slow as existing sources are gradually discarded.In contrast,concentrations of BDE-47(mean=5.7 ng/g;median=0.93 ng/g)and BDE-99(mean=11 ng/g;median=2.9 ng/g)were significantly lower than in all previous(p<0.01)studies in the same city since 2006,suggesting restrictions on the Penta-BDE formulation have been effective.The average BDE-209 concentration(4800 ng/g;median=1600 ng/g)is lower than the peak average concentration,which was observed in 2007(280,000 ng/g),however this is not a significant decline,probably due to the later imposition of Deca-BDE restrictions compared to those on Penta-BDE.Decreases in PBDE concentrations have coincided with a significant(p<0.01)increase in DBDPE concentrations(average=1500 ng/g;median=660 ng/g)since 2014,suggesting its use as a replacement flame retardant for Deca-BDE.While no significant change was detected for BTBPE(average 11 ng/g;median=0.84 ng/g in this study);concentrations of TBBPA(average=34 ng/g;median=35 ng/g)were significantly lower(p<0.05)than in 2007(average 62 ng/g).The decreases observed in PBDE concentrations,demonstrates that legislation has been effective in reducing the commercial use of PBDEs,however this has coincided with increases of alternative flame retardants such as DBDPE. 展开更多
关键词 Brominated Flame Retardants(BFRs) Polybrominated diphenyl ethers(PBDEs) Hexabromocyclododecane(HBCDD) Decabromodiphenyl ethane(DBDPE) Stockholm convention Tetrabromobisphenol A(TBBPA) BTBPE
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欧洲汽车动力系统多元化的发展趋势和展望 被引量:1
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作者 徐宏明 《汽车安全与节能学报》 CAS CSCD 北大核心 2024年第2期137-153,共17页
当前,全球能源结构处在变革时期,低碳和零碳化是包括汽车行业在内的所有经济运行和规划活动中的重中之重。汽车动力系统的能源呈现多元化的发展趋势,始于轻型车的电动化已成为不可逆转的总体方向,而氢时代在到来之前面临各种技术和非技... 当前,全球能源结构处在变革时期,低碳和零碳化是包括汽车行业在内的所有经济运行和规划活动中的重中之重。汽车动力系统的能源呈现多元化的发展趋势,始于轻型车的电动化已成为不可逆转的总体方向,而氢时代在到来之前面临各种技术和非技术类等诸多问题的挑战。电动化带来的一个更为广泛应用的新技术是人工智能(AI),从而使得汽车动力系统逐步突破传统设计方法的局限得以适应更加复杂的环境条件并获得高效率。该文介绍欧洲汽车动力系统电动化和多元化的发展趋势,针对欧盟正在考虑中的电力合成燃料等问题并结合动力系统智能化等发展趋势,对欧洲汽车技术领域在2035年前的研发动向作出相关思考以及展望。 展开更多
关键词 碳中和 动力多元化 电动汽车(EV) 清洁能源 电子燃料(e-fuels) 人工智能(AI)
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直流电网及其运行控制策略发展趋势
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作者 李周 王宇涵 +1 位作者 顾伟 张小平 《电力系统自动化》 EI CSCD 北大核心 2024年第24期1-21,共21页
在中国构建清洁低碳安全高效的能源体系以及新型电力系统发展目标指导下,为支撑未来电网进行大范围、高效、灵活的资源配置,构建直流电网来实现多类能源汇集、跨区域电能输送、区域电网互联及交直流灵活互动等功能已成为直流输电系统的... 在中国构建清洁低碳安全高效的能源体系以及新型电力系统发展目标指导下,为支撑未来电网进行大范围、高效、灵活的资源配置,构建直流电网来实现多类能源汇集、跨区域电能输送、区域电网互联及交直流灵活互动等功能已成为直流输电系统的重要发展趋势。目前,直流电网正朝着拓扑结构复杂化、接线方式多样化、换流技术混合化以及运行控制场景多元化方向发展。文中从直流电网发展趋势出发,分析梳理了可用于直流电网各层级、各类型的交直流运行控制策略,进一步梳理了直流电网不同运行控制场景下控制策略间的多时空耦合关系,总结分析了未来直流电网运行控制领域的潜在研究热点。 展开更多
关键词 新型电力系统 交直流混联 区域电网 直流电网 运行控制
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兰炭灰固碳对复合相变储热材料性能的影响
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作者 熊亚选 尹心成 +4 位作者 药晨华 任静 吴玉庭 张灿灿 丁玉龙 《热力发电》 CAS CSCD 北大核心 2024年第7期62-72,共11页
为推动“双碳”战略,促进工业固废兰炭灰的低成本消纳,开发新型绿色低碳复合材料,提出在已有的兰炭灰/硝酸钠复合相变储热材料基础上,利用兰炭灰进行碳捕捉。对固碳前、后兰炭灰及复合相变储热材料的性能进行研究。结果表明:兰炭灰碳捕... 为推动“双碳”战略,促进工业固废兰炭灰的低成本消纳,开发新型绿色低碳复合材料,提出在已有的兰炭灰/硝酸钠复合相变储热材料基础上,利用兰炭灰进行碳捕捉。对固碳前、后兰炭灰及复合相变储热材料的性能进行研究。结果表明:兰炭灰碳捕集的最佳条件为气体组分20%CO_(2)/80%N_(2)、通气时间40 min、加热温度650℃;在最佳实验条件下,兰炭灰的固碳率达到29.27%,所制得的复合相变储热材料固碳兰炭灰/NaNO_(3)的最佳质量比为5:5,在100~380℃储热密度达到288.65 J/g,拥有更好的机械性能、热稳定性及化学相容性。固碳兰炭灰作为骨架材料制备复合相变储热材料具有较好的可行性,为工业固废兰炭灰的资源化利用和碳排放处理提供了新的途径。 展开更多
关键词 固体废弃物 骨架材料 复合材料 储热性能 力学性能
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污泥焚烧炉渣/硝酸钾复合相变储热材料制备及性能
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作者 熊亚选 尹心成 +4 位作者 宋超宇 任静 张灿灿 吴玉庭 丁玉龙 《储能科学与技术》 CAS CSCD 北大核心 2024年第10期3357-3368,共12页
未妥善处理的市政污泥会导致部分的生态环境受到不可逆的影响,通过焚烧处理可有效缓解所带来的危害。但污泥焚烧炉渣中又存在难以固定的重金属。为有效解决重金属的固定问题,同时制备低成本、环境友好的复合相变储热材料,提出以市政污... 未妥善处理的市政污泥会导致部分的生态环境受到不可逆的影响,通过焚烧处理可有效缓解所带来的危害。但污泥焚烧炉渣中又存在难以固定的重金属。为有效解决重金属的固定问题,同时制备低成本、环境友好的复合相变储热材料,提出以市政污泥焚烧炉渣作为骨架材料,硝酸钾为相变储热材料,采用冷压-烧结法制备5种不同质量比的污泥焚烧炉渣/硝酸钾复合相变储热材料,并对其宏观形貌、微观形貌、抗压性能、热稳定性、化学相容性、传热储热性能、经济性及CO_(2)排放量进行表征和分析。结果表明,在100~380℃范围内,污泥焚烧炉渣与硝酸钾的最佳质量比为5∶5(样品SC3),储热密度为322.45 J/g,潜热为41.75 J/g,最大热导率为1.04 W/(m·K);抗压强度达到153.78 MPa;两者间具有良好的化学相容性,且在样品SC3中均匀分布;经1000次加热/冷却循环后的样品SC3具有良好的高温热稳定性;储热成本为63.06元/MJ;总CO_(2)排放量为1083.53 kg/t,低于传统骨架材料基复合相变储热材料的总CO_(2)排放量,有较好的环境效益,具有较好的可行性。 展开更多
关键词 市政污泥 骨架材料 储热 热稳定性 化学相容性
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中国海洋经济高质量发展区域差异与收敛性
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作者 肖健华 胡琪琴 肖昊玥 《五邑大学学报(自然科学版)》 CAS 2024年第1期70-78,共9页
为了探索我国海洋经济高质量发展的时空异质性与收敛性,本文基于五大新发展理念,构建包含“经济发展、科技创新、生态环境、社会民生、对外开放”五大领域的海洋经济高质量发展评价指标体系,并运用突变级数法测度2007—2019年我国沿海1... 为了探索我国海洋经济高质量发展的时空异质性与收敛性,本文基于五大新发展理念,构建包含“经济发展、科技创新、生态环境、社会民生、对外开放”五大领域的海洋经济高质量发展评价指标体系,并运用突变级数法测度2007—2019年我国沿海11省市海洋经济高质量发展水平,采用泰尔指数及收敛模型分别考察海洋经济高质量发展水平的动态分布、差异来源和收敛趋势.研究结果表明,全国及三大海洋经济圈海洋经济高质量发展综合指数呈先上升后下降趋势,各地区海洋经济发展水平具有显著差异性,表明我国海洋经济发展的非均衡性有所加剧,而区域内差异是导致总体差异变化的主要因素.东部海洋经济圈存在σ收敛,而全国及北部、南部海洋经济圈不存在σ收敛.全国及三大海洋经济圈存在绝对β收敛,并且条件β收敛也显著. 展开更多
关键词 海洋经济 高质量发展 突变级数法 泰尔指数 收敛性分析
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基于中国全科医生的糖尿病医患沟通技能培训设计与开发 被引量:3
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作者 姚弥 林恺 +10 位作者 樊洁婷 纪欣鑫 王颖 董爱梅 韩晓宁 齐建光 迟春花 Shamil Haroon Dawn Jackson KK Cheng Richard Lehman 《中国全科医学》 北大核心 2024年第7期816-821,共6页
全科医生作为居民健康“守门人”,在基层糖尿病等慢性疾病管理中发挥着重要作用。糖尿病管理可以延缓病情进展、减少糖尿病并发症和改善患者健康结局,这需要患者和医生之间的有效沟通并互相协作。全科医生具备良好的沟通能力有助于与糖... 全科医生作为居民健康“守门人”,在基层糖尿病等慢性疾病管理中发挥着重要作用。糖尿病管理可以延缓病情进展、减少糖尿病并发症和改善患者健康结局,这需要患者和医生之间的有效沟通并互相协作。全科医生具备良好的沟通能力有助于与糖尿病患者建立长期的照护关系、帮助患者建立有效的自我管理技能。本文总结了本研究团队在多种理论框架指导下的全科医生糖尿病沟通技能培训的设计和开发:基于系统综述发现的循证依据,通过定性研究进一步探索糖尿病患者与全科医生的沟通体验和想法,以及混合方法研究设计理念获取全科医学对于医患沟通培训内容的优先排序,旨在为高质量的基层糖尿病管理提供新思路,并为基于证据和医学教育框架设计全科医生相关培训项目提供借鉴。 展开更多
关键词 糖尿病 沟通技能 在职培训 培训设计 全科医生
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基于在线特征库的非侵入式负荷特征提取方法 被引量:1
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作者 王谱宇 耿路路 +3 位作者 刘兴江 程含渺 方凯杰 张小平 《中国电机工程学报》 EI CSCD 北大核心 2024年第9期3489-3499,I0012,共12页
负荷特征是指负荷设备运行过程中具备某种统计规律的特殊标识,而包含负荷特征的数据库则是实现非侵入式负荷监测与分解的基本依据。对于纯阻性负荷设备,研究人员利用其运行状态切换过程中功率产生跃变的特点,可以准确提取相应状态下的... 负荷特征是指负荷设备运行过程中具备某种统计规律的特殊标识,而包含负荷特征的数据库则是实现非侵入式负荷监测与分解的基本依据。对于纯阻性负荷设备,研究人员利用其运行状态切换过程中功率产生跃变的特点,可以准确提取相应状态下的负荷特征。然而,对非纯阻性设备,其负荷特征提取存在以下2个问题。问题1)运行状态切换过程中功率变化不显著,无法精准定位状态投切时刻点;问题2)负荷设备存在功率缓变化的运行状态,导致对应状态下的负荷特征不唯一,无法手动提取。为了解决非纯阻性设备负荷特征提取中存在的上述问题,提出一种基于在线特征库的非侵入式负荷特征提取方法,该方法分为2个阶段。第一阶段:基于负荷设备运行过程中的稳态周期电流数组建立在线特征库,通过改进Pearson相似系数构建滑窗函数,得到负荷设备运行时的周期电流数组与在线特征库的相似性,并同步判断在线特征库冗余性,实现负荷设备状态数据分割;第二阶段:计算在线特征库的特征矩阵,对特征矩阵进行K-means聚类分析,融合相似在线特征库,形成负荷设备的状态特征库,从而实现负荷设备特征电流数组的提取。在私人数据集和PLAID数据集上的测试结果证明,所提负荷特征提取方法在不同的用电场景下均有较好的鲁棒性。所提方法可大幅减少负荷特征提取阶段的人工参与,有利于缓解因负荷设备种类过多导致的负荷特征提取烦琐的问题,为后续建立负荷特征数据库提供了便利。 展开更多
关键词 状态检测 负荷特征 周期电流数组 在线特征库 K-MEANS算法
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双相钢与铝合金异种金属激光焊接技术研究进展
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作者 李昂 曾一达 +5 位作者 李智勇 贺荣 郭正华 陈玉华 江一 杨子睿 《材料导报》 EI CAS CSCD 北大核心 2024年第22期214-222,共9页
随着汽车行业对减重、节能需求的增加,近年来铝合金等轻质材料广泛应用在车身结构件中。双相钢与铝合金异种金属激光焊接中,材料物化性能差异大导致焊缝成形差、接头强度低,主要原因是钢/铝界面处生成的Fe-Al金属间化合物(Intermetallic... 随着汽车行业对减重、节能需求的增加,近年来铝合金等轻质材料广泛应用在车身结构件中。双相钢与铝合金异种金属激光焊接中,材料物化性能差异大导致焊缝成形差、接头强度低,主要原因是钢/铝界面处生成的Fe-Al金属间化合物(Intermetallic compounds,IMC)脆性大、硬度高,焊接接头存在较大的残余应力,致使焊接接头性能恶化。本文综述了工艺窗口和冶金调控对焊缝成形的影响规律,并阐述了飞溅、烧损、裂纹等焊接缺陷的控制措施,总结了焊接参数和不同中间层元素对界面中间相的种类、数量以及接头力学性能的影响规律,分析了不同中间层元素(Pb、Sn、Ti、Cu、Mn、Si等)在焊接过程的作用和特点,并展望了双相钢/铝合金异种金属激光焊接的未来发展趋势。 展开更多
关键词 激光焊接 双相钢 异种金属 中间相
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液态空气储能耦合综合能源系统热电联储联供优化配置研究
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作者 黄思远 王晨 +4 位作者 梁婷 姜竹 李佳静 折晓会 张小松 《储能科学与技术》 CAS CSCD 北大核心 2024年第6期1929-1939,共11页
液态空气储能(LAES)在多能耦合的综合能源系统中极具应用前景,合理的储能容量配置更有利于综合能源系统低碳经济运行,但目前研究未充分考虑LAES热电联储联供强相关的特性和优势。因此,本文提出了一种LAES耦合综合能源系统的热电联储联... 液态空气储能(LAES)在多能耦合的综合能源系统中极具应用前景,合理的储能容量配置更有利于综合能源系统低碳经济运行,但目前研究未充分考虑LAES热电联储联供强相关的特性和优势。因此,本文提出了一种LAES耦合综合能源系统的热电联储联供优化配置方法,针对综合能源系统的基本架构,构建了各组成单元的热电联储/供调度约束模型,并以设备初始投资成本、设备运维成本、购能成本、弃风弃光成本等为目标函数,考虑了系统能量平衡约束、设备容量约束、设备出力约束、外网交互功率约束以及储能约束,建立了相应的优化配置模型,并基于混合整数线性规划方法进行模型求解。以某实际园区为例,设置了5种场景进行优化结果对比分析,结果表明:考虑LAES热电联储联供特性的综合能源系统能实时有效地满足系统用能需求,同时能实现更好的经济效益和环境效益,相较于传统分供系统,系统总经济成本下降37.1%,实现碳减排71.50%,并在消纳可再生能源和减少弃光弃风方面更具潜力。本研究可为LAES耦合系统热电联储联供优化模型的有效性提供理论依据,有助于推动LAES在综合能源系统中的商业化应用。 展开更多
关键词 液态空气储能 综合能源系统 热电联储联供 配置优化 混合整数线性规划
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先进压缩空气储能系统的基础研究与应用进展 被引量:2
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作者 Xinjing Zhang Ziyu Gao +4 位作者 Bingqian Zhou Huan Guo Yujie Xu Yulong Ding Haisheng Chen 《Engineering》 SCIE EI CAS CSCD 2024年第3期246-269,共24页
Decarbonization of the electric power sector is essential for sustainable development.Low-carbon generation technologies,such as solar and wind energy,can replace the CO_(2)-emitting energy sources(coal and natural ga... Decarbonization of the electric power sector is essential for sustainable development.Low-carbon generation technologies,such as solar and wind energy,can replace the CO_(2)-emitting energy sources(coal and natural gas plants).As a sustainable engineering practice,long-duration energy storage technologies must be employed to manage imbalances in the variable renewable energy supply and electricity demand.Compressed air energy storage(CAES)is an effective solution for balancing this mismatch and therefore is suitable for use in future electrical systems to achieve a high penetration of renewable energy generation.This study introduces recent progress in CAES,mainly advanced CAES,which is a clean energy technology that eliminates the use of fossil fuels,compared with two commercial CAES plants at Huntorf and McIntosh which are conventional ones utilizing fossil fuels.Advanced CAES include adiabatic CAES,isothermal CAES,liquid air energy storage,supercritical CAES,underwater CAES,and CAES coupled with other technologies.The principles and configurations of these advanced CAES technologies are briefly discussed and a comprehensive review of the state-of-the-art technologies is presented,including theoretical studies,experiments,demonstrations,and applications.The comparison and discussion of these CAES technologies are summarized with a focus on technical maturity,power sizing,storage capacity,operation pressure,round-trip efficiency,efficiency of the components,operation duration,and investment cost.Potential application trends were compiled.This paper presents a comprehensive reference for developing novel CAES systems and makes recommendations for future research and development to facilitate their application in several areas,ranging from fundamentals to applications. 展开更多
关键词 Compressed air energy storage FUNDAMENTALS APPLICATIONS Technological parameters COMPARISON
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2024 Wheelchair Compendium of Physical Activities:An update of activity codes and energy expenditure values 被引量:4
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作者 Scott A.Conger Stephen D.Herrmann +3 位作者 Erik A.Willis Tom E.Nightingale Joseph R.Sherman Barbara E.Ainsworth 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期18-23,共6页
Purpose:This paper presents an update of the 2011 Wheelchair Compendium of Physical Activities designed for wheelchair users and is referred to as the 2024 Wheelchair Compendium.The Wheelchair Compendium aims to curat... Purpose:This paper presents an update of the 2011 Wheelchair Compendium of Physical Activities designed for wheelchair users and is referred to as the 2024 Wheelchair Compendium.The Wheelchair Compendium aims to curate existing knowledge of the energy expenditure for wheelchair physical activities(PAs).Methods:A systematic review of the published energy expenditure of PA for wheelchair users was completed between 2011 and May 2023.We added these data to the 2011 Wheelchair Compendium data that was compiled previously in a systematic review through 2011.Results:A total of 47 studies were included,and 124 different wheelchair PA reported energy expenditure values ranging from 0.8 metabolic equivalents for wheelchair users(filing papers,light effort)to 11.8 metabolic equivalents for wheelchair users(Nordic sit skiing).Conclusion:In introducing the updated 2024 Wheelchair Compendium,we hope to bridge the resource gap and challenge the prevailing narratives that inadvertently exclude wheelchair users from physical fitness and health PAs. 展开更多
关键词 DISABILITY EXERCISE MET Mobility
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