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Spatiotemporal Evolution of Urban Heat Islands and Optimization of Spatial Network Construction in the Central Urban Area of Fuzhou City, China
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作者 ZHAO Qiuyue YU Kunyong +3 位作者 GENG Jianwei LIN Jiqing AI Jingwen LIU Jian 《Chinese Geographical Science》 SCIE CSCD 2024年第5期917-930,共14页
Although accelerated urbanization has led to economic prosperity,it has also resulted in urban heat island effects.Therefore,identifying methods of using limited urban spaces to alleviate heat islands has become an ur... Although accelerated urbanization has led to economic prosperity,it has also resulted in urban heat island effects.Therefore,identifying methods of using limited urban spaces to alleviate heat islands has become an urgent issue.In this study,we assessed the spatiotemporal evolution of urban heat islands within the central urban area of Fuzhou City,China from 2010 to 2019.This assessment was based on a morphological spatial pattern analysis(MSPA)model and an urban thermal environment spatial network constructed us-ing the minimum cumulative resistance(MCR)model.Optimization measures for the spatial network were proposed to provide a theor-etical basis for alleviating urban heat islands.The results show that the heat island area within the study area gradually increased while that of urban cold island area gradually decreased.The core area was the largest of the urban heat island patch landscape elements with a significant impact on other landscape elements,and represented an important factor underlying urban heat island network stability.The thermal environment network revealed a total of 197 thermal environment corridors and 93 heat island sources.These locations were then optimized according to the current land use,which maximized the potential of 1599.83 ha.Optimization based on current land use led to an increase in climate resilience,with effective measures showing reduction in thermal environment spatial network structure and function,contributing to the mitigation of urban heat island.These findings support the use of current land use patterns during urban heat island mitigation measure planning,thus providing an important reference basis for alleviating urban heat island effects. 展开更多
关键词 urban heat island spatiotemporal analysis circuit theory post optimization evaluation climate mitigation Fuzhou City China
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Alfvén continuum in the presence of a magnetic island in a cylinder configuration
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作者 杨骏辉 曹锦佳 +2 位作者 赵建华 戴勇智 向东 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第3期40-50,共11页
In this work,the effect of a magnetic island on Alfvén waves is studied.A physical model is established wherein Alfvén waves propagate in the presence of a magnetic island in a cylindrical geometry.The struc... In this work,the effect of a magnetic island on Alfvén waves is studied.A physical model is established wherein Alfvén waves propagate in the presence of a magnetic island in a cylindrical geometry.The structure of the Alfvén wave continuum is calculated by considering only the coupling caused by the periodicity in the helical angle of the magnetic island.The results show that the magnetic island can induce an upshift in the Alfvén continuum.Moreover,the coupling between different branches of the continuous spectrum becomes more significant with increasing continuum mode numbers near the boundary of the magnetic island. 展开更多
关键词 Alfvén waves cylindrical geometry magnetic island continuum coupling
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Coupling coordination analysis of Mazu culture,socio-economy and ecological environment of Meizhou Island
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作者 FU Wei-jia WU Ying-qi +2 位作者 LUO Zi-xuan YAO Jun-bing FU Li-jun 《Ecological Economy》 2024年第1期85-100,共16页
Taking the pilgrimage,tourism and cultural island of Meizhou Island as an example,the evaluation index system of the coupling and coordinated development of“Mazu culture,socio-economy,eco-environment”(MSE)compound s... Taking the pilgrimage,tourism and cultural island of Meizhou Island as an example,the evaluation index system of the coupling and coordinated development of“Mazu culture,socio-economy,eco-environment”(MSE)compound system was constructed.The index weights were determined by AHP-entropy method,and the coupling degree,coordinated degree,comprehensive evaluation index and grey correlation degree of MSE system of Mazu Island from 2012 to 2022 were measure.The results showed that:(1)the comprehensive evaluation indexes of the three subsystems was on the rise in general,but the evaluation index of the ecological subsystems increased relatively slowly.(2)The coupling degree was only in the running-in stage in 2012,and the other years were in the coordinated coupling stage.(3)The coupling coordination degree increased from 0.35 in 2012 to 0.82 in 2022,the coupling coordination level was changed from mild imbalance to good coordination.(4)Through the comparison of grey correlation degree,the 24 indexes in the evaluation index system had great influence on the coupling coordination degree of MSE system.The coupling coordination degree was closely related to the development of socio-economy and the spread of Mazu culture.With the rapid development of tourism brought about by the spread of Mazu culture,the pressure on the ecological environment will be increasing.Compared with the rapid growth of tourism and economy,it is equally important to strengthen environmental protection and pay attention to the quality of ecological environment development. 展开更多
关键词 Meizhou island Mazu culture socio-economy ecological environment comprehensive evaluation index coupling coordination degree
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The incorporation of emotion-regulation skills into couple-and family-based treatments for post-traumatic stress disorder
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作者 Deborah A.Perlick Frederic J.Sautter +5 位作者 Julia J.Becker-Cretu Danielle Schultz Savannah C.Grier Alexander V.Libin Manon Maitland Schladen Shirley M.Glynn 《Military Medical Research》 SCIE CAS 2017年第4期218-228,共11页
Post-traumatic stress disorder(PTSD) is a disabling, potentially chronic disorder that is characterized by re-experience and hyperarousal symptoms as well as the avoidance of trauma-related stimuli. The distress exper... Post-traumatic stress disorder(PTSD) is a disabling, potentially chronic disorder that is characterized by re-experience and hyperarousal symptoms as well as the avoidance of trauma-related stimuli. The distress experienced by many veterans of the Vietnam War and their partners prompted a strong interest in developing conjoint interventions that could both alleviate the core symptoms of PTSD and strengthen family bonds. We review the evolution of and evidence base for conjoint PTSD treatments from the Vietnam era through the post-911 era. Our review is particularly focused on the use of treatment strategies that are designed to address the emotions that are generated by the core symptoms of the disorder to reduce their adverse impact on veterans, their partners and the relationship. We present a rationale and evidence to support the direct incorporation of emotion-regulation skills training into conjoint interventions for PTSD. We begin by reviewing emerging evidence suggesting that high levels of emotion dysregulation are characteristic of and predict the severity of both PTSD symptoms and the level of interpersonal/marital difficulties reported by veterans with PTSD and their family members. In doing so, we present a compelling rationale for the inclusion of formal skills training in emotional regulation in couple–/family-based PTSD treatments. We further argue that increased exposure to trauma-related memories and emotions in treatments based on learning theory requires veterans and their partners to learn to manage the uncomfortable emotions that they previously avoided. Conjoint treatments that were developed in the last 30 years all acknowledge the importance of emotions in PTSD but vary widely in their relative emphasis on helping participants to acquire strategies to modulate them compared to other therapeutic tasks such as learning about the disorder or disclosing the trauma to a loved one. We conclude our review by describing two recent innovative treatments for PTSD that incorporate a special emphasis on emotion-regulation skills training in the dyadic context: structured approach therapy(SAT) and multi-family group for military couples(MFG-MC). Although the incorporation of emotion-regulation skills into conjoint PTSD therapies appears promising, replication and comparison to cognitive-behavioral approaches is needed to refine our understanding of which symptoms and veterans might be more responsive to one approach versus others. 展开更多
关键词 couples FAMILY post-traumatic stress disorder emotional regulation
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The Coupling of Voltage and Frequecncy Response in Splitting Island and Its Effects on Load-shedding Relays
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作者 Hao Yang Baohui Zhang 《Energy and Power Engineering》 2013年第4期661-666,共6页
The voltage and frequency dynamics interact with each other in the island after splitting. The current frequency response model without considering the voltage effect would bring remarkable errors when analyzing the f... The voltage and frequency dynamics interact with each other in the island after splitting. The current frequency response model without considering the voltage effect would bring remarkable errors when analyzing the frequency dynamic progress in the island with large-capacity active-power shortage. In this paper, coupling effects of voltage and frequency are studied to indicate that initial reactive-power deficit and load characteristics have strong effects on the coupling effects of the voltage and frequency. Moreover, control effects of currently used under frequency load-shedding relays (UFLS) and under voltage load-shedding relays (UVLS) which are installed and executed independently are examined to find that it would sometimes cause excessive or inadequate control without considering the coupling, suggesting that it is necessary to develop coordinate control methods for voltage and frequency problems. 展开更多
关键词 Frequency RESPonSE COUPLinG EFFECTS SPLITTinG island Coordination Control
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Numerical Computation of Resonant Frequency of Shorting Post Loaded Gap-Coupled Circular Microstrip Patch Antennas
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作者 Pradeep KUMAR G. SINGH T. CHAKRAVARTY 《Journal of Electromagnetic Analysis and Applications》 2009年第4期259-264,共6页
In this paper, the numerical computation of resonant frequency of the two gap-coupled circular microstrip patch antenna loaded with shorting post by using cavity model is presented. The numerically computed results ar... In this paper, the numerical computation of resonant frequency of the two gap-coupled circular microstrip patch antenna loaded with shorting post by using cavity model is presented. The numerically computed results are compared with simulated results. The two gap-coupled circular microstrip patch antenna loaded with shorting post miniaturize the cross-sectional dimension of the radiating patch at the microwave frequency, which is useful for short range communications or contactless identification systems. The simulation has been performed using method-of-moments based commercially available simulator IE3D. 展开更多
关键词 Gap-Coupling MICROSTRIP ANTENNAS Shorting post RESonANT Frequency
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POST-PLATFORM MOUNTAIN-AND BASIN-MAKING MODEL IN HAINAN ISLAND OF CHINA:GEOCHEMICAL CONSTRAINTS FROM IGNEOUS ROCKS
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作者 Zou Heping(Department of Earth Sciences, Zhongshan University, Guangzhou 510275) 《Geotectonica et Metallogenia》 1998年第Z1期42-50,共9页
Since the late Hercynian episode the crust in Hainan has entered the post-platform activation or the diwa stage in which it has undergone a process from compressive (collision) orogeny and up1ifting during the late He... Since the late Hercynian episode the crust in Hainan has entered the post-platform activation or the diwa stage in which it has undergone a process from compressive (collision) orogeny and up1ifting during the late Hercynian-Indosinian movements to block-faulting type mountain- and basin-making during the Yanshanian-Himalayan movements. It has been shown through researches of igneous rocks that a post-platform orogenic belt being of a greatly thickened continental crust was once formed in the Hainan area during the late Hercynian-lndosinian cyc1e. The taphrogeny starting in the late Yanshanian episode was a product at the stage of late orogenic extension under conditions of the mountain root with a thickness of about 60 km retained. At 1ast, the lower lithospheric delamination and the crustal de-rooting of the orogen caused Hainan and its neighboring areas to transform from the continenta1 type crustobody to the continental-margin-spreading type crustobody. 展开更多
关键词 Igneous rock post-platform activation (diwa) mountain-and basin-making Hainan island
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Control of Distributed Generation Using Non-Sinusoidal Pulse Width Modulation
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作者 Mehrdad Ahmadi Kamarposhti Phatiphat Thounthong +1 位作者 Ilhami Colak Kei Eguchi 《Computers, Materials & Continua》 SCIE EI 2023年第2期4149-4164,共16页
The islanded mode is one of the connection modes of the grid distributed generation resources.In this study,a distributed generation resource is connected to linear and nonlinear loads via a three-phase inverter where... The islanded mode is one of the connection modes of the grid distributed generation resources.In this study,a distributed generation resource is connected to linear and nonlinear loads via a three-phase inverter where a control method needing no current sensors or compensator elements is applied to the distribute generation system in the islanded mode.This control method has two main loops in each phase.The first loop controls the voltage control loops that adjust the three-phase point of common coupling,the amplitude of the non-sinusoidal reference waveform and the near-state pulse width modulation(NSPWM)method.The next loop compensates the harmonic compensator loop that calculates the voltage harmonics of the point of common coupling in each phase,and injects them to compensate the non-sinusoidal reference waveforms of each phase.The simulation results in MATLAB/SIMULINK show that this method can generate balanced threephase sinusoidal voltage with an acceptable total harmonic distortion(THD)at the joint connection point. 展开更多
关键词 islanded mode distributed generation resource the point of common coupling voltage total harmonic distortion
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Forging process modeling of cone-shaped posts
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作者 XuefengLiu LingyunWang LiZhang 《Journal of University of Science and Technology Beijing》 CSCD 2004年第3期256-259,共4页
Using the rigid visco-plastic Finite Element Method (FEM), the process offorging for long cone-shaped posts made of aluminum alloys was modeled and the correspondingdistributions of the field variables were obtained b... Using the rigid visco-plastic Finite Element Method (FEM), the process offorging for long cone-shaped posts made of aluminum alloys was modeled and the correspondingdistributions of the field variables were obtained based on considering aberrance of grids, dynamicboundary conditions, non-stable process, coupled thermo-mechanical behavior and other specialproblems. The difficulties in equipment selection and die analysis caused by the long cone shape ofpost, as well as by pressure calculation were solved. 展开更多
关键词 coupled thermo-mechanical analysis constitutive relationship rigidvisco-plastic FEM cone-shaped post
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Effects and complications of placement of motility coupling post in porous polyethylene orbital implants
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作者 Hong-guang CUI Rong-rong HU Hui-yan LI Wei HAN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第6期464-469,共6页
Objective: To investigate the effects and complications of primary and secondary placements of motility coupling post (MCP) in the unwrapped porous polyethylene orbital implant (PPOI) following enucleation. Meth... Objective: To investigate the effects and complications of primary and secondary placements of motility coupling post (MCP) in the unwrapped porous polyethylene orbital implant (PPOI) following enucleation. Methods: We investigated 198 patients who received PPOI implantation following the standard enucleation procedure in the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China, from 2002 to 2004. These patients were subgrouped into PPOI-only patients (112 cases, received PPOI following enucleation), primary MCP patients (46 cases, received primary placement of MCP during PPOI operation), and secondary MCP patients (40 cases, received secondary placement ofMCP 6 months after the initial surgery). Effects and complications among these three groups were compared. Results: The PPOI-only patients took shorter treatment course when compared with other two MCP groups (P〈0.001), without significant difference noted between the two MCP groups. However, the two MCP groups had better prosthetic motility than PPOI-only group (P〈0.001), without significant difference between the two MCP groups. In the early stage, 2 eyes in the PPOI-only group and l eye in the primary MCP group had PPOI infection. In PPOI-only group, 3 (2.68%) eyes had PPOI exposure, which occurred after fitting the prostheses; 4 eyes (8.70%) in primary MCP group and 1 eye (2.50%) in secondary MCP had PPOI exposure, which occurred before fitting the prostheses. After prosthesis was fit successfully, the excessive discharge and granuloma were 33.9% and 1.79% in PPOI group-only, 53.3% and 8.9% in primary MCP group, and 52.5% and 7.5% in secondary MCP group, respectively. Conclusion: Both primary and secondary placements of MCP into the PPOI following enucleation can help patients to obtain desirable prosthetic motility, but may be associated with more complications. The primary placement of MCP with skilled operation in selected patients is more recommendable than secondary placement. 展开更多
关键词 Porous polyethylene orbital implant (PPOI) Motility coupling post (MCP)
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Temperature field analysis of main steam pipe under local post weld heat treatment 被引量:4
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作者 李培麟 樊睿智 陆皓 《China Welding》 EI CAS 2010年第4期20-24,共5页
In local post weld heat treatment, the temperature difference is the criterion of the process. The temperature field in the main stream pipe under local post weld heat treatment is simulated by finite element method. ... In local post weld heat treatment, the temperature difference is the criterion of the process. The temperature field in the main stream pipe under local post weld heat treatment is simulated by finite element method. A close-loop control program is designed to simulate the temperature field of two different pipes. Both the skin effect of induction heating and electro-thermal coupled effect are considered in the heating model. The local heat treatment temperature difference at the inner and outer side of the pipe is analyzed and the different convection conditions are also considered. The simulation results show that in appropriate induction heating process, the temperature difference in the pipe can be controlled within 30 ℃. 展开更多
关键词 local post weld heat treatment temperature field electro-thermal coupling numerical simulation
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Mechanisms of High Coercivity in Ni/NiO Composite Films by Post Annealing 被引量:5
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作者 J.B. Yi J. Ding +4 位作者 Mansoor Bin Abdul Jalil B.H. Liu S. Thongmee J.H. Yin Z.L. Zhao 《材料科学与工程学报》 CAS CSCD 北大核心 2007年第6期858-860,共3页
A coercivity as large as 2.4 kOe has been achieved in the Ni/NiO composite film after an annealing under a magnetic field of 10 kOe and an O_2 partial pressure of 0.001 torr.The coercivity was attributed to the strong... A coercivity as large as 2.4 kOe has been achieved in the Ni/NiO composite film after an annealing under a magnetic field of 10 kOe and an O_2 partial pressure of 0.001 torr.The coercivity was attributed to the strong exchange coupling of Ni and NiO.Small grain size of Ni and NiO was observed after the post-annealing.The enhanced coercivity is probably associated with the domain wall pinning by local energy minima,the distribution of Ni and NiO,and the domain structure in the interface of Ni/NiO generated under the presence of the magnetic field during the post-annealing. 展开更多
关键词 矫顽性 镍氧化镍复合薄膜 焊后退火 交换耦合
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基于InfoWorks ICM的城市河网调控与分析--以福州市仓山区龙津阳岐片区为例 被引量:3
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作者 周紫蕊 廖卫红 +1 位作者 雷晓辉 梁永帅 《南水北调与水利科技(中英文)》 CAS CSCD 北大核心 2023年第4期770-779,共10页
针对典型感潮河网地区水环境污染日趋严重与洪涝灾害频发的问题,为优化河网水动力和降低河道漫溢风险,基于Info Works ICM(integrated catchment management)模型建立福州市仓山区龙津阳岐片区城市水文模型与一维河网水动力耦合模型,以2... 针对典型感潮河网地区水环境污染日趋严重与洪涝灾害频发的问题,为优化河网水动力和降低河道漫溢风险,基于Info Works ICM(integrated catchment management)模型建立福州市仓山区龙津阳岐片区城市水文模型与一维河网水动力耦合模型,以2022年6月14日实测降雨及河道水位数据对模型参数进行校准,平均纳什效率系数为0.78,平均洪峰误差为1.5%。设计并模拟3种晴天工况和3种“卢碧”台风雨天工况,结果表明:晴天从无调控到工况3,随着引水量的增加,河网平均流速逐步增加,总体增加66.4%,河道水动力提升显著;雨天从原有调控工况到工况3,随着河道预降水位值增大,关键断面平均超警历时逐步减少,总体下降73%,河道漫溢风险明显降低。构建河网水文水动力耦合模型和工况优选,可为仓山区进一步提升河网水动力与城市汛期洪涝灾害防治能力的方案制定提供决策依据,也可为其他同类研究提供借鉴。 展开更多
关键词 南台岛 双向感潮河网 水文水动力耦合 情景调控 河网平均流速 超警历时
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深中通道岛隧结合部波流特性及覆盖层稳定性试验研究
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作者 聂晓彤 刘军其 +2 位作者 戈龙仔 陈汉宝 刘海源 《水道港口》 2024年第4期486-494,共9页
基于岛隧工程结合部与传统隧道、近岸陆地工程衔接存在明显差别,以及在设计上面临的新难题,为保证深中通道岛隧结合部沉管隧道覆盖层在极端恶劣条件下的安全性和可靠性,对结合部区域范围内波流特性和防护结构的稳定性进行了研究。通过... 基于岛隧工程结合部与传统隧道、近岸陆地工程衔接存在明显差别,以及在设计上面临的新难题,为保证深中通道岛隧结合部沉管隧道覆盖层在极端恶劣条件下的安全性和可靠性,对结合部区域范围内波流特性和防护结构的稳定性进行了研究。通过开展物理模型试验,模拟了包括波浪和水流之间变化角度的水动力场,以及波流耦合作用护面块体稳定性;揭示了岛隧结合部波流耦合效应,总结了波高比(H_(s)′/H_(s))和流速比(U′/U)与相对流速(U/C)、波陡(H_(s)/L)、相对水深(d/L)和波流夹角(α)变化规律,并导出了相应的计算公式;同时通过多组试验对比优化,获得了护面块体最优稳定重量,导出了波流耦合作用下护面块体稳定重量的计算方法。研究结果不仅解决了深中通道重大工程的实际问题,也为今后海底沉管隧道覆盖层的建设提供基础数据和技术支撑。 展开更多
关键词 深中通道工程 岛隧结合部覆盖层 波流耦合 稳定性 模型试验
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考虑移动式储能调度的配电网灾后多源协同孤岛运行策略 被引量:1
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作者 王育飞 李可铭 +2 位作者 薛花 于艾清 米阳 《电力系统自动化》 EI CSCD 北大核心 2024年第3期62-72,共11页
针对极端事件导致的配电网大面积停电现象,在路-电耦合背景下,提出一种考虑移动式储能调度的配电网灾后多源协同孤岛运行策略。首先,基于路-电耦合背景下的灾后运行框架,以加权切负荷量最小为目标,同时考虑交通流量的变化对移动式储能... 针对极端事件导致的配电网大面积停电现象,在路-电耦合背景下,提出一种考虑移动式储能调度的配电网灾后多源协同孤岛运行策略。首先,基于路-电耦合背景下的灾后运行框架,以加权切负荷量最小为目标,同时考虑交通流量的变化对移动式储能调度过程的影响,建立多源协同孤岛运行模型;然后,根据所建模型的特点以及决策需求,基于两阶段优化框架制定孤岛运行决策流程,确保失电孤岛区域与含本地电源区域负荷恢复的协调进行;最后,采用IEEE 33节点配电网与29节点交通路网相耦合的算例进行分析,验证所提策略的有效性。结果表明,所提孤岛运行策略可以充分发挥各电源在配电网灾后恢复时的协同能力,实现了有限电能的最优分配和转移,有效提升了配电网灾后恢复效果。 展开更多
关键词 有源配电网 移动式储能系统 调度 路-电耦合 多源协同 孤岛运行 两阶段优化
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南京市中心医院综合楼原址新建项目单侧大悬挑超限高层结构设计
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作者 韩重庆 戴璐 +1 位作者 黄远 陈乾 《建筑结构》 北大核心 2024年第16期107-113,68,共8页
南京市中心医院综合楼原址新建项目用地狭小、高度受限且基底面积被周边地下室挤占,采用了单侧大悬挑的结构体型。在充分考虑造价和施工可行性的前提下,经分析对比,得出以下结论:高层建筑大悬挑部位可采用具有结构高度小、不影响室内空... 南京市中心医院综合楼原址新建项目用地狭小、高度受限且基底面积被周边地下室挤占,采用了单侧大悬挑的结构体型。在充分考虑造价和施工可行性的前提下,经分析对比,得出以下结论:高层建筑大悬挑部位可采用具有结构高度小、不影响室内空间、安装方便等优点的钢结构叠层空腹桁架;通过对空腹桁架进行合理的子结构拆分,在竖腹杆中间设置可锁紧滑动节点,可实现空腹桁架的无支架施工并消除楼层间由施工次序引起的不均匀内力;空腹桁架叠层较多时,由支承柱竖向变形引起的次内力不能忽略;为解决新建项目与周边既有地下室间距离很近的问题,可采用高承载力后注浆钻孔灌注桩、地下室外墙单面立模、拔除周边地下室基坑支护桩等措施;低烈度区钢筋混凝土框架-剪力墙结构的地震损伤主要发生在连梁部位,采用可更换钢连梁有利于实现结构中震正常使用的性能目标。 展开更多
关键词 超限高层建筑 性能化设计 单侧大悬挑 空腹桁架 钻孔灌注桩 可更换钢连梁
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弯剪耦合作用下大尺寸碳纤维C型梁失效损伤模式分析
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作者 赵紫昱 杨曈 +1 位作者 张发 马丕波 《纺织学报》 EI CAS CSCD 北大核心 2024年第2期93-100,共8页
为进一步探究大尺寸碳纤维C型梁结构抗弯剪屈曲的承载性能,提出了一种可同时施加弯曲和剪切载荷并任意调节弯剪比的试验装置。通过设计3种不同弯剪耦合条件进行试验载荷的加载,使用应变片监测大尺寸碳纤维C型梁结构在屈曲以及后屈曲阶... 为进一步探究大尺寸碳纤维C型梁结构抗弯剪屈曲的承载性能,提出了一种可同时施加弯曲和剪切载荷并任意调节弯剪比的试验装置。通过设计3种不同弯剪耦合条件进行试验载荷的加载,使用应变片监测大尺寸碳纤维C型梁结构在屈曲以及后屈曲阶段应变分布状况。通过有限元模型对基于不同损伤准则的后屈曲行为进行预测。研究结果表明:大尺寸碳纤维C型梁在抗弯和抗弯剪耦合的载荷条件下,都具有优良的后屈曲承载能力;在2种弯剪耦合条件下,试验件分别在3.28倍和2.3倍设计载荷时发生梁腹板失稳现象,试验件进入后屈曲状态,继续进行弯剪耦合载荷的加载,达到4.6倍设计载荷后,样品出现局部损伤;采用Hashin和LaRC05准则对试验件损伤情况进行预测,破坏损伤形式分别为沿45°方向开始向外扩展和上部翼缘扭曲破坏。 展开更多
关键词 大尺寸C型梁 弯剪耦合 应变测量 后屈曲 损伤预测
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深中通道西人工岛现浇隧道后浇筑墙体控裂技术研究及应用
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作者 郑伟涛 王从李 +1 位作者 王朔 刘帅 《中国港湾建设》 2024年第7期28-33,共6页
深中通道西人工岛处于外海环境,岛上现浇隧道结构尺寸大,断面宽度及墙身高度呈渐变形式。施工过程中,为确保隧道主线临时通行需求,对敞开段隧道结构墙体进行部分预留,待交通转换后进行浇筑封闭。因其龄期间隔时间长,新老混凝土间易因收... 深中通道西人工岛处于外海环境,岛上现浇隧道结构尺寸大,断面宽度及墙身高度呈渐变形式。施工过程中,为确保隧道主线临时通行需求,对敞开段隧道结构墙体进行部分预留,待交通转换后进行浇筑封闭。因其龄期间隔时间长,新老混凝土间易因收缩不同步造成结构开裂。为降低混凝土开裂风险,确保海工混凝土结构耐久性,对外海现浇隧道后浇筑墙体开展系统性控裂研究,通过采用有限元仿真模拟分析、研发智能温控系统、辅以温控硬件措施投入等综合控裂措施,实现后浇筑墙体控裂目标,有效避免了墙体有害裂缝的发生。 展开更多
关键词 深中通道 西人工岛 后浇筑墙体 大体积混凝土 控裂
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InAs/GaAs系列量子点研究
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作者 王建峰 商耀辉 +2 位作者 武一宾 牛晨亮 卜夏正 《微纳电子技术》 CAS 北大核心 2009年第7期410-413,共4页
为了获得波长长、均匀性好和发光效率高的量子点,采用分子束外延(MBE)技术和S-K应变自组装模式,在GaAs(100)衬底上研究生长了三种InAs量子点。采用MBE配备的RHEED确定了工艺参数:As压维持在1.33×10-5Pa;InAs量子点和In0.2Ga0.8As... 为了获得波长长、均匀性好和发光效率高的量子点,采用分子束外延(MBE)技术和S-K应变自组装模式,在GaAs(100)衬底上研究生长了三种InAs量子点。采用MBE配备的RHEED确定了工艺参数:As压维持在1.33×10-5Pa;InAs量子点和In0.2Ga0.8As的生长温度为500℃;565℃生长50nmGaAs覆盖层。生长了垂直耦合量子点(InAs1.8ML/GaAs5nm/InAs1.8ML)、阱内量子点(In0.2Ga0.8As5nm/InAs2.4ML/In0.2Ga0.8As5nm)和柱状岛量子点(InAs分别生长1.9、1.7、1.5ML,停顿20s后,生长间隔层GaAs2nm)。测得对应的室温光致发光(PL)谱峰值波长分别为1.038、1.201、1.087μm,半峰宽为119.6、128.0、72.2nm、相对发光强度为0.034、0.153、0.29。根据PL谱的峰位、半峰宽和相对发光强与量子点波长、均匀性和发光效率的对应关系,可知量子点波长有不同程度的增加、均匀性越来越好、发光效率显著增强。 展开更多
关键词 自组装量子点 垂直耦合量子点 阱内量子点 柱状岛量子点 S-K模式 分子束外延 光致发光谱
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A direct coupling analysis method and its application to the Scientific Research and Demonstration Platform 被引量:2
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作者 Jun Ding You-sheng Wu +6 位作者 Xin-yun Ni Qi-bin Wang Yu-chao Chen Yong-lin Ye Xin-yu Zhang Yu-xiang Ma Wei-nan Yang 《Journal of Hydrodynamics》 SCIE EI CSCD 2021年第1期13-23,共11页
Design of a very large floating structure(VLFS)deployed near islands and reefs,different from those in the open sea,inevitably faces new technical challenges including numerical analysis methods.In this paper,a direct... Design of a very large floating structure(VLFS)deployed near islands and reefs,different from those in the open sea,inevitably faces new technical challenges including numerical analysis methods.In this paper,a direct coupling analysis method(DCAM)has been established based on the Boussinesq equations and the three-dimensional hydroelasisity theory with Rankine source method to analyze the responses of a VLFS in shallow sea with complicated geographical environment.Model tests have been carried out to validate the DCAM.To further verify the numerical methods and investigate the performance of such a VLFS,a“Scientific Research and Demonstration Platform(SRDP)”was built and deployed in 2019 at the site about 1000 m off an island with water depth around 40m in South China Sea.It is a simplified small model of a two-module semi-submersible-type VLFS.The numerical simulation of its responses on severe waves with focus on motions and connector forces is conduct by DCAM,and compared with the on-site measurements.Good agreement has been achieved.This approves the DCAM as a feasible tool for design and safety assessment of a VLFS deployed near islands and reefs. 展开更多
关键词 Very large floating structure(VLFS) hydroelastic analysis near island direct coupling analysis method model test on-site measurement verification
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