检索结果-南通市图书馆

Surrogate-assisted differential evolution using manifold learning-based sampling for highdimensional expensive constrained optimization problems

引用

Chinese Journal of Aeronautics 2024年第7期37卷 252-270页

作者： teng long Nianhui YE Rong CHEN Renhe SHI Baoshou ZHANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Dynamics and Control of Flight Vehicle of Ministry of Education Beijing 100081China China Academy of Launch Vehicle Technology Beijing 100076China

To address the challenges of high-dimensional constrained optimization problems with expensive simulation models,a Surrogate-Assisted Differential Evolution using Manifold Learning-based Sampling(SADE-MLS)is *** SADE-MLS,differential evolution operators are executed to generate numerous high-dimensional candidate *** alleviate the curse of dimensionality,a Manifold Learning-based Sampling(MLS)mechanism is developed to explore the high-dimensional design space *** MLS,the intrinsic dimensionality of the candidate points is determined by a maximum likelihood ***,the candidate points are mapped into a low-dimensional space using the dimensionality reduction technique,which can avoid significant information loss during dimensionality ***,Kriging surrogates are constructed in the low-dimensional space to predict the responses of the mapped candidate *** candidate points with high constrained expected improvement values are selected for global ***,the local search process assisted by radial basis function and differential evolution is performed to exploit the design space *** numerical benchmarks are tested to compare SADE-MLS with other ***,SADE-MLS is successfully applied to a solid rocket motor multidisciplinary optimization problem and a re-entry vehicle aerodynamic optimization problem,with the total impulse and lift to drag ratio being increased by 32.7%and 35.5%,*** optimization results demonstrate the practicality and effectiveness of the proposed method in real engineering practices.

关键词： Surrogate-assisted differential evolution Dimensionality reduction Solid rocket motor Re-entry vehicle Expensive constrained optimization

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Dielectric ultracapacitors based on columnar nano-grained ferroelectric oxide films with gradient phases along the growth direction

引用

Journal of Advanced Ceramics 2024年第7期13卷 1072-1079页

作者： Chuanqi Song Feifan Zheng Yuan Zhang Hongbo Cheng long teng Kun Wang Hanfei Zhu Chao Liu Li Wang Zhengyan Liang Jun Ouyang Institute of Advanced Energy Materials and Chemistry School of Chemistry and Chemical EngineeringQilu University of Technology(Shandong Academy of Sciences)Jinan 250353China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Key Laboratory of Key Film Materials&Application for Equipment(Hunan Province) School of Materials Science and EngineeringXiangtan UniversityXiangtan 411105China China Tobacco Shandong Industrial Co. Ltd.Jinan 250104China

In this work,dielectric ultracapacitors were designed and fabricated using a combination of phase boundary and nanograin *** ultracapacitors are based on submicron-thick Ba(Zr_(0.2)Ti_(0.8))O_(3) ferroelectric films sputterdeposited on Si at 500℃.With a composition near a polymorphic phase boundary(PPB),a compressive strain,and a high nucleation rate due to the lowered deposition temperature,these films exhibit a columnar nanograined microstructure with gradient phases along the growth *** a microstructure presents three-dimensional polarization inhomogeneities on the nanoscale,thereby significantly delaying the saturation of the overall electric ***,a pseudolinear,ultraslim polarization(P)-electric field(E)hysteresis loop was obtained,featuring a high maximum applicable electric field(~5.7 MV/cm),low remnant polarization(~5.2μC/cm^(2))and high maximum polarization(~92.1μC/cm^(2)).This P-E loop corresponds to a high recyclable energy density(W_(rec)~208 J/cm^(3))and charge‒discharge efficiency(~88%).An indepth electron microscopy study revealed that the gradient ferroelectric phases consisted of tetragonal(T)and rhombohedral(R)polymorphs along the growth direction of the *** T-rich phase is abundant near the bottom of the film and gradually transforms into the R-rich phase near the *** films also exhibited a high Curie temperature of~460℃and stable capacitive energy storage up to 200℃.These results suggest a feasible pathway for the design and fabrication of high-performance dielectric film capacitors.

关键词： ferroelectric thin films energy storage phase coexistence nanograin silicon

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Shared mooring systems for offshore floating wind farms: A review

引用

Energy Reviews 2024年第1期3卷 76-89页

作者： Hang Xu Shengjie Rui Kanmin Shen Liangliang Jiang Haojie Zhang long teng Zhejiang Key Laboratory of Offshore Geotechnics and Material College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou310058China Norwegian Geotechnical Institute Sandakerveien 140Oslo0484Norway PowerChina Huadong Engineering Corporation Limited Hangzhou311122China Department of Chemical and Petroleum Engineering The University of CalgaryCalgaryAlbertaCanada

Offshore wind energy,as a form of renewable power,has seen rapid development in recent *** fixedbottom wind turbines are typically used in water depths less than 50 m,the utilization of floating offshore wind turbines(FOWTs)becomes essential for deeper *** and effective mooring systems play a crucial role in making FOWTs commercially *** concept of a shared mooring system offers an innovative solution for deploying floating wind farms in clusters or arrays,which can reduce overall construction costs for large-scale floating wind *** is imperative to optimize the shared mooring arrangement for maximum cost-effectiveness and wind farm ***,implementing a shared mooring system introduces complexity to the dynamics of FOWTs,requiring the development of advanced simulation tools to meet modelling *** the shared mooring arrangement,mooring lines and anchors face more significant challenges,such as chain-seabed interactions,soil cyclic weakening,and anchor out-of-plane loading,which underscore the need for innovative,reliable,and efficient shared anchor *** article offers an overview of the current research status on shared mooring systems for floating wind farms,which might serve as a valuable reference for the construction of large-scale floating wind farms worldwide.

关键词： Floating offshore wind turbines Wind farm Shared mooring Shared anchor Renewable energy

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

ZNF554 Inhibits Endometrial Cancer Progression via Regulating RBM5 and Inactivating WNT/β-Catenin Signaling Pathway

引用

Current Medical Science 2024年第2期44卷 406-418页

作者： Cheng-cheng ZHU Heng-liang SUN teng-fei long Yuan-yuan LYU Jiang-li LIU Guan-tai NI Anhui Medical University Hefei 230032China Department of Obstetrics and Gynecology The First Affiliated Hospital of Wannan Medical CollegeWuhu 241001China

Objective:Uterine corpus endometrial carcinoma(UCEC),a kind of gynecologic malignancy,poses a significant risk to women’s *** precise mechanism underlying the development of UCEC remains *** finger protein 554(ZNF554),a member of the Krüppel-associated box domain zinc finger protein superfamily,was reported to be dysregulated in various illnesses,including malignant *** study aimed to examine the involvement of ZNF554 in the development of ***:The expression of ZNF554 in UCEC tissues and cell lines were examined by qRT-PCR and Western blot *** with stably overexpressed or knocked-down ZNF554 were established through lentivirus ***-8,wound healing,and Transwell invasion assays were employed to assess cell proliferation,migration,and *** iodide(PI)staining combined with fluorescence-activated cell sorting(FACS)flow cytometer was utilized to detect cell cycle ***-PCR and Western blotting were conducted to examine relative mRNA and protein *** immunoprecipitation assay and luciferase reporter assay were used to explore the regulatory role of ZNF554 in RNA binding motif 5(RBM5).Results:The expression of ZNF554 was found to be reduced in both UCEC samples and cell *** expression of ZNF554 was associated with higher tumor stage,decreased overall survival,and reduced disease-free survival in ***554 overexpression suppressed cell proliferation,migration,and invasion,while also inducing cell cycle *** contrast,a decrease in ZNF554 expression resulted in the opposite ***,ZNF554 transcriptionally regulated RBM5,leading to the deactivation of the Wingless(WNT)/β-catenin signaling ***,the findings from rescue studies demonstrated that the inhibition of RBM5 negated the impact of ZNF554 overexpression onβ-catenin and p-glycogen synthase kinase-3β(p-GSK-3β).Similarly,the deliberate activation of RBM5 reduced the increase inβ-catenin and

关键词： zinc finger protein 554 endometrial carcinoma RNA binding motif 5 Wingless/β-catenin signaling pathway

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

3D printing for ultra-precision machining:current status,opportunities,and future perspectives

引用

Frontiers of Mechanical Engineering 2024年第4期19卷 1-28页

作者： Tao HE Wai Sze YIP Edward Hengzhou YAN Jiuxing TANG Muhammad REHAN long teng Chi Ho WONG Linhe SUN Baolong ZHANG Feng GUO Shaohe ZHANG Suet TO State Key Laboratory of Ultra-precision Machining Technology Department of Industrial and Systems EngineeringThe Hong Kong Polytechnic UniversityHong KongChina Department of Industrial and Systems Engineering The Hong Kong Polytechnic UniversityHong KongChina Department of Physics The Hong Kong University of Science and TechnologyHong KongChina School of Geosciences and Info-Physics Central South UniversityChangsha 410083China

Additive manufacturing,particularly 3D printing,has revolutionized the manufacturing industry by allowing the production of complex and intricate parts at a lower cost and with greater ***,3D-printed parts frequently require post-processing or integration with other machining technologies to achieve the desired surface finish,accuracy,and mechanical ***-precision machining(UPM)is a potential machining technology that addresses these challenges by enabling high surface quality,accuracy,and repeatability in 3D-printed *** study provides an overview of the current state of UPM for 3D printing,including the current UPM and 3D printing stages,and the application of UPM to 3D *** the presentation of current stage perspectives,this study presents a detailed discussion of the benefits of combining UPM with 3D printing and the opportunities for leveraging UPM on 3D printing or supporting each *** particular,future opportunities focus on cutting tools manufactured via 3D printing for UPM,UPM of 3D-printed components for real-world applications,and post-machining of 3D-printed ***,future prospects for integrating the two advanced manufacturing technologies into potential industries are *** study concludes that UPM is a promising technology for 3D-printed components,exhibiting the potential to improve the functionality and performance of 3D-printed products in various *** also discusses how UPM and 3D printing can complement each other.

关键词： ultra-precision machining 3D printing additive manufacturing future perspectives start-of-the-art-review

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

人口老龄化是否助推了顺周期财政风险?

引用

经济体制改革 2024年第4期 168-174页

作者：龙腾王希元广东财经大学财政税务学院广东广州510320 云南大学经济学院云南昆明650504

人口老龄化会增加养老部门需求,可能成为推动我国顺周期财政风险的重要因素。基于1990~2020年世界52个经济体的面板数据,分析人口老龄化对财政政策顺周期风险的影响、机制及相关变量的异质性问题。研究发现:人口老龄化会推动财政政策的... 详细信息

人口老龄化会增加养老部门需求,可能成为推动我国顺周期财政风险的重要因素。基于1990~2020年世界52个经济体的面板数据,分析人口老龄化对财政政策顺周期风险的影响、机制及相关变量的异质性问题。研究发现:人口老龄化会推动财政政策的顺周期特性,增加顺周期财政风险,税收约束和赤字规模则是人口老龄化间接推动顺周期财政风险的重要因素;在经济衰退期,由于政府在顺周期紧缩性政策框架下的财政能力衰退,增量养老需求无法得到有效的财政支持,导致老龄化在顺周期紧缩性政策框架下的影响不显著;而具备“富而过老”特征的经济体,老龄化对财政政策顺周期性的影响效果更为明显。因此,我国需根据人口年龄结构的关键特征,充分发挥平抑经济波动的调控职能,缓解内部和外部财政约束,构建开放型经济新体制,推动中国财政政策周期由“顺”转“逆”。

关键词：老龄化顺周期财政风险财政平衡机制检验

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

基于样本映射与动态Kriging的飞行器离散连续优化方法

引用

航空学报 2024年第3期45卷 143-159页

作者：李昊达龙腾史人赫叶年辉北京理工大学宇航学院北京100081 北京理工大学飞行器动力学与控制教育部重点实验室北京100081 北京理工大学重庆创新中心重庆401121

针对复杂飞行器系统离散连续混合优化计算成本高、全局收敛性差等问题,提出了一种基于样本映射与动态Kriging的离散连续优化方法(SMDK-DC)。该方法采用Kriging代理模型代替高耗时仿真模型以降低计算成本,并定制一种基于综合曼哈顿距离... 详细信息

针对复杂飞行器系统离散连续混合优化计算成本高、全局收敛性差等问题,提出了一种基于样本映射与动态Kriging的离散连续优化方法(SMDK-DC)。该方法采用Kriging代理模型代替高耗时仿真模型以降低计算成本,并定制一种基于综合曼哈顿距离准则的样本点映射机制,在连续-离散空间内高效生成满足均布性要求的真实样本点。将期望改善度准则与重点采样空间方法相结合,辨识优质新增样本点,持续动态更新Kriging,引导离散连续优化过程快速收敛。标准数值算例测试结果表明,与SOMI、NOMAD等国际同类方法相比,SMDK-DC方法在全局收敛性与鲁棒性方面具有显著优势。使用该方法求解固体火箭发动机多学科设计优化问题,优化方案在满足燃烧室、内弹道等学科约束条件前提下,使得发动机总冲提升12.92%以上,且优化收益较SOMI方法提高1.71%,从而验证了本文工作的有效性与工程实用性。

关键词： Kriging 离散连续混合优化近似优化期望改善度重点采样空间

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

地埋式生活污水处理厂造价影响因素分析与造价指标对比

引用

工程造价管理 2024年第3期35卷 72-76页

作者：龙腾广州市市政工程研究总院有限公司广东广州510000

地埋式生活污水处理厂是一种常见的污水处理设施,具有节约空间、降低污水处理成本等优势,然而,其造价受到多种因素的影响。文章旨在分析地埋式生活污水处理厂造价的影响因素,并对不同造价指标进行比较研究。首先对地埋式生活污水处理厂... 详细信息

地埋式生活污水处理厂是一种常见的污水处理设施,具有节约空间、降低污水处理成本等优势,然而,其造价受到多种因素的影响。文章旨在分析地埋式生活污水处理厂造价的影响因素,并对不同造价指标进行比较研究。首先对地埋式生活污水处理厂的基坑及地下主体框架部分、设备购置及安装工程部分、土建工程部分、污泥处理部分、外水外电部分分项费用占比进行了分析;然后对地埋式生活污水处理厂的造价影响因素进行了分析,影响因素包括固定因素(建设规模和技术工艺)和可变因素(市场、材料、施工等);最后提出了地埋式生活污水处理厂造价影响因素在设计阶段、施工阶段和竣工决算阶段的控制措施。文章可为地埋式生活污水处理厂的设计、建设和运营提供参考,有助于其优化成本控制和提高处理效率。

关键词：地埋式污水处理造价影响因素指标对比

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

地铁地下车站工程项目土建工程费指标和计算模型研究——以广州地铁8号线文化公园站为例

引用

价值工程 2024年第24期43卷 79-81页

作者：龙腾广州市市政工程研究总院有限公司广州510000

本研究以广州地铁8号线文化公园站工程项目为例,旨在建立地铁地下车站土建工程费的指标体系和计算模型,并探讨相应的研究方法。通过对已完成的地铁车站工程项目数据的分析和整理,将土建工程费的各个组成部分进行归纳和分类,建立起合理... 详细信息

本研究以广州地铁8号线文化公园站工程项目为例,旨在建立地铁地下车站土建工程费的指标体系和计算模型,并探讨相应的研究方法。通过对已完成的地铁车站工程项目数据的分析和整理,将土建工程费的各个组成部分进行归纳和分类,建立起合理的土建工程费指标体,同时建立可靠的土建工程费计算模型。通过本研究的开展,可以为地铁地下车站工程项目提供科学的土建工程费预测和控制方法,为工程管理决策提供参考依据,降低工程成本,提高工程质量和效率。

关键词：地铁地下车站土建工程费指标计算模型

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

两阶段特征金字塔的遥感图像变化检测

引用

信号处理 2024年第3期40卷 471-483页

作者：庄胤蔡妙鑫董珊陈禾龙腾北京理工大学雷达技术研究院北京100081 北京理工大学雷达技术研究院空天遥感研究所北京100081

遥感图像变化检测是遥感领域的重要研究方向。针对多尺度编码特征语义差异性和空间信息差异性引入伪变化干扰的问题,本文提出了一种两阶段特征金字塔的变化检测网络TS-FPCDN(Two Stage-Feature Pyramid based Change Detection Network)... 详细信息

遥感图像变化检测是遥感领域的重要研究方向。针对多尺度编码特征语义差异性和空间信息差异性引入伪变化干扰的问题,本文提出了一种两阶段特征金字塔的变化检测网络TS-FPCDN(Two Stage-Feature Pyramid based Change Detection Network),通过两阶段解码器增强变化特征描述,抑制伪变化信息干扰。首先,采用孪生编码网络对双时相遥感影像进行编码特征提取,并生成多尺度初始差异特征。由于初始差异特征中存在大量噪声和伪变化信息,通过第一阶段特征金字塔结构和双注意力引导的多尺度差异特征融合机制,进行多尺度差异特征语义信息和空间信息的交互,缓解多尺度特征语义的差异性和空间信息的差异性,初步去除伪变化信息干扰,生成多尺度初始变化特征。然后,为进一步提高变化特征描述和去除伪变化,设计了第二阶段特征金字塔,对多尺度变化特征逐层重优化,并进行变化预测。最后,在两个变化检测数据集LEVIR-CD和WHU-CD上开展了一系列实验,实验结果证明了本文提出方法的有效性。

关键词：遥感影像变化检测注意力机制特征金字塔

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：