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Discovery of unusual phloroglucinol-triterpenoid adducts from Leptospermum scoparium and Xanthostemon chrysanthus by building blocks-based molecular networking 被引量:3
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作者 Jinyan Zhang Fen Liu +7 位作者 Qian Jin Xueyi Li Qiong Zhan Mu Chen Sisi Wang Zhenlong Wu Wencai Ye Lei Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第6期353-357,共5页
The first phloroglucinol-triterpenoid hybrids,myrtphlotritins A-E(1-5),were rapidly recognized and isolated from two species of Myrtaceae by employing the building blocks-based molecular network(BBMN)strategy.Compound... The first phloroglucinol-triterpenoid hybrids,myrtphlotritins A-E(1-5),were rapidly recognized and isolated from two species of Myrtaceae by employing the building blocks-based molecular network(BBMN)strategy.Compounds 1-5 featured new carbon skeletons in which phloroglucinol derivatives were coupled with lupane-and dammarane-type triterpenoids through different linkage patterns.Their structures and absolute configurations were elucidated by comprehensive analysis of spectroscopic data and quantum chemical calculations.Biosynthetic pathways for compounds 1-5 were proposed on the basis of the coexisting precursors.Guided by the biogenetic pathways,the biomimetic synthesis of compound 1 was also achieved.Additionally,compounds 2,3,and 5 exhibited potent antiviral activities against herpes simplex virus type-1(HSV-1)infection,and compounds 2 and 5 displayed significant anti-inflammatory activities on RAW264.7 cells. 展开更多
关键词 Phloroglucinol-triterpenoid adduct MYRTACEAE building blocks-based molecular network Biomimetic synthesis Antiviral activity Anti-inflammatory activity
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Design of Building Monitoring Systems Based on Wireless Sensor Networks 被引量:2
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作者 Qifen Dong Li Yu +2 位作者 Huanjia Lu Zhen Hong Yourong Chen 《Wireless Sensor Network》 2010年第9期703-709,共7页
Wireless Sensor Network provides a potential technique for monitoring the indoor environment. This paper presents a Building Monitoring system based on Wireless Sensor Networks. A clustering-based network specified fo... Wireless Sensor Network provides a potential technique for monitoring the indoor environment. This paper presents a Building Monitoring system based on Wireless Sensor Networks. A clustering-based network specified for building monitoring is proposed, which is inspired by LEACH (Low Energy Adaptive Cluster Hierarchy) method. Further, two key ideas are used to implement the clustering-based network. First, the configuration module of building management software is used to conduct all nodes in a room forming a local cluster. This cluster formation method does not consume node energy. Second, because cluster-heads cannot directly transmit packets to the sink node due to limited wireless communication range, the cluster-head communications are represented by a multi-hop tree rooted at the sink node. The experiment has been made to demonstrate the feasibility of the proposed results. 展开更多
关键词 WIRELESS SENSOR networkS buildING Monitoring LEACH CLUSTER
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Improved Implementation and Evaluation of Wireless Sensor Networks in Intelligent Building 被引量:3
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作者 段俊奇 张思东 郑涛 《China Communications》 SCIE CSCD 2011年第8期64-71,共8页
A complete study for the implementation of wireless sensor networks in the intelligent building is presented. We carry out some experiments to find out the factors affecting the network performance. Several vital para... A complete study for the implementation of wireless sensor networks in the intelligent building is presented. We carry out some experiments to find out the factors affecting the network performance. Several vital parameters which are related to the link quality are measured before deploying the actual system. And then, we propose an optimized routing protocol based on the analysis of the test data. We evaluate the deployment strategies to ensure the excellent performance of the wireless sensor networks under the real working conditions. And the evaluation results show that the presented system could satisfy the requirements of the applications in the intelligent building. 展开更多
关键词 wireless sensor networks deployment strategy network parameters routing protocol intelligent building
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A WiFi-ZigBee Building Area Network Design of High Traffics AMI for Smart Grid 被引量:1
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作者 Hoi Yan Tung Kim Fung Tsang +3 位作者 Hoi Ching Tung Veseline Rakocevic Kwok Tai Chui Yat Wah Leung 《Smart Grid and Renewable Energy》 2012年第4期324-333,共10页
A WiFi-ZigBee hybrid BAN solution, namely WiZBAN, is proposed and implemented to cater for the development of high traffic AMI for smart grid application. It is important to highlight that the major challenge of WiZBA... A WiFi-ZigBee hybrid BAN solution, namely WiZBAN, is proposed and implemented to cater for the development of high traffic AMI for smart grid application. It is important to highlight that the major challenge of WiZBAN is to handle the high density environment which results in heavy traffic loading and weak signal propagation. To overcome the captioned problem, Vertical Backbone Communication (VBC) and Horizontal Floor Communication (HFC) are defined for WiZBAN. The WiZBAN consists of WiZBAN Gateway (WiZGW), WiZBAN Meter Hub (WiZBAN) and WiZBAN In Home Display (WiZIHD) which caters for the smart grids services including smart metering and demand response. The WiZGW is the entrance of WiZBAN and connects WiZBAN to utilities. The WiZGW also teams up with WiZMH to enables VBC. On the other hand, WiZMH serves as the interception point of VBC and HFC. It interacts with smart meters and sets up the HFC together with WiZIHD to provide the user interface for end users. To shorten the transmission time, WiFi is adopted for VBC while ZigBee is applied to HCF to overcome the weak signal propagation. To investigate the performance of WiZBAN, a case study has been conducted based on an existing 23 floor residential building. From the measured and simulated results, the average round trip delay of demand response and smart metering are found to be 0.6 s and 9 s respectively. 展开更多
关键词 ADVANCE METERING INFRASTRUCTURE building Area network WIFI ZIGBEE Delay
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Seismic vulnerability assessment of urban buildings and traffic networks using fuzzy ordered weighted average 被引量:1
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作者 Yasaman ASADI Najmeh Neysani SAMANY Keyvan EZIMAND 《Journal of Mountain Science》 SCIE CSCD 2019年第3期677-688,共12页
Urban buildings and urban traffic network are considered as the vital arteries of cities which have particular effects especially after the crisis in the search and rescue operations. The aim of this study is to deter... Urban buildings and urban traffic network are considered as the vital arteries of cities which have particular effects especially after the crisis in the search and rescue operations. The aim of this study is to determine the vulnerability of urban areas especially, buildings and traffic networks using multicriteria geographic information systems and decisionmaking methods. As there are many effective criteria on the seismic vulnerability that they have uncertain and vague properties, the method of this paper is applying fuzzy ordered weighted average(OWA) to model the seismic vulnerability of urban buildings and traffic networks in the most optimistic and pessimistic states. The study area is district 6 of Tehran that is affected by the four major faults, and thus will be threatened by the earthquakes. The achieved results illustrated the vulnerability with different degrees of risk levels including very high, high, medium, low and very low. The results show that in the most optimistic case 14% and in the pessimistic case 1% of buildings tolerate in very low vulnerability. The vulnerability of urban street network also indicates that in the optimistic case 12% and in the pessimistic case at most 9% of the area are in appropriate condition and the North and NorthEast of the study area are more vulnerable than South of it. 展开更多
关键词 Earthquake Vulnerability Assessment URBAN buildINGS Traffic network MULTI-CRITERIA Decision Analysis(MCDA) Fuzzy-OWA
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ZTE to Build SDR Network for Portugal's Optimus
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作者 ZTE Corperation 《ZTE Communications》 2010年第1期12-12,共1页
ZTE Corporation, a leading global provider of telecommunications equipment and network solutions, announced on February 24, 2010 that Optimus will be deploying its software define radio (SDR) multi-mode solution, en... ZTE Corporation, a leading global provider of telecommunications equipment and network solutions, announced on February 24, 2010 that Optimus will be deploying its software define radio (SDR) multi-mode solution, enabling the operator to upgrade its GSM/UMTS network in Portugal and providing a smooth evolution path to LTE. ZTE's SDR network will include SDR RAN, network management system, and operation systems and software (NMS/OSS), enabling Optimus to optimize current 2G/3G services and smoothly upgrade to LTE. 展开更多
关键词 SDR UMTS ZTE to build SDR network for Portugal’s Optimus
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Neural Network Approach to Response of Buildings Due to Earthquake Excitation
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作者 Sayantan Chakraborty Prashant Kumar Swapan Kumar Chakraborty 《International Journal of Geosciences》 2012年第3期630-639,共10页
The present article investigates the physical phenomena associated with the wave passage effect into a building considering the ground floor as the soft floor with the conformity of the up-to-date scenario of the cons... The present article investigates the physical phenomena associated with the wave passage effect into a building considering the ground floor as the soft floor with the conformity of the up-to-date scenario of the construction of high rise buildings, due to shear excitation of the base. The aim of the study is to analyse the post-earthquake situation of the building in respect to its health. With this vision, the ensuing problem on two-dimensional building models, non-incorporating soil-structure interaction, is being tackled by both analytical and neural network approaches. Computational results from both ends (of the approaches) show that the wave energy does not always propagate from the ground into the building, but for lower frequency range it sails to the building without any disturbances. However, for higher frequency range, the computational results show that the building experiences large “torsional” deformations, as a result the building may collapse. Finally, both the approaches maintain a good agreement among themselves. The present investigation may lead to a long way in contributing to better and more rational, simplified design criteria. 展开更多
关键词 NEURAL network ANISOTROPIC building SOFT Ground FLOOR
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ZTE to Build IMS Core Network for China Mobile
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作者 ZTE Corporation 《ZTE Communications》 2010年第2期24-24,共1页
ZTE Corporation, a leading global provider of telecommunications equipment and network solutions, announced on April 26, 2010 that it has been chosen by China Mobile to deliver its IMS core network in key Chinese prov... ZTE Corporation, a leading global provider of telecommunications equipment and network solutions, announced on April 26, 2010 that it has been chosen by China Mobile to deliver its IMS core network in key Chinese provinces. The China Mobile' s commercial IMS network will boast 1.4 million lines when it is completed in three months. According to the comprehensive evaluation process by China Mobile, ZTE was ranked among the tier one IMS supplier group for the project this time. 展开更多
关键词 ZTE to build IMS Core network for China Mobile IMS CORE
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Zapp Selects ZTE to Build 3G Network in Romania
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《ZTE Communications》 2008年第2期14-14,共1页
ZTE, a leading global provide of telecommunications equipment and network sulutions, announced on May 29, 2008 that it has been selected by Zapp, Romania’s fourth largest mobile operator, to roll-out a WCDMA/HSDPA co... ZTE, a leading global provide of telecommunications equipment and network sulutions, announced on May 29, 2008 that it has been selected by Zapp, Romania’s fourth largest mobile operator, to roll-out a WCDMA/HSDPA commercial network. This deal reinforces ZTE position in Europe. Zapp plans on launching its 3G commercial services in early autumn 2008 and the network should be completed by 2011. 展开更多
关键词 ZTE Zapp Selects ZTE to build 3G network in Romania WCDMA
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ZTE Softswitch the Working Solution to Build the New Generation Network
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作者 ZTE CORPORATION 《ZTE Communications》 2003年第2期7-7,共1页
ZTE Softswitch supports the interoperability and convergence oflegacy PSTN/ISDN, PLMN, IN, and the Internet, allowing operatorsor service providers to offer diversified services to any subscriber atany time on a ZTE S... ZTE Softswitch supports the interoperability and convergence oflegacy PSTN/ISDN, PLMN, IN, and the Internet, allowing operatorsor service providers to offer diversified services to any subscriber atany time on a ZTE Softswitch network.With powerful C4 and C5 features, ZTE Softswitch effectivelysolves the evolution problems in the existing networks, protectinglegacy network investment and reducing future investment to a prof-itable level for providers. 展开更多
关键词 ZTE Softswitch the Working Solution to build the New Generation network in on for TIME
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China Builds Optical Fibre Tele-trunk Network
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作者 Wang Hualong 《China's Foreign Trade》 1995年第8期31-31,共1页
In early 1995 China began to build eight optical fibre cable trunks, including the 4,532km-long Hangzhou-Fuzhou-Guiyang-Chengdu trunk in southern China, the 2,133km-long Beijing-Hohhot-Yinchuan-Lanzhou trunk in the no... In early 1995 China began to build eight optical fibre cable trunks, including the 4,532km-long Hangzhou-Fuzhou-Guiyang-Chengdu trunk in southern China, the 2,133km-long Beijing-Hohhot-Yinchuan-Lanzhou trunk in the northern part of the country, and the 3,000km-long Beijing-Wuhan-Guangzhou trunk across the country. They will be put into use by the end of the year, thus finalizing the construction of 22 A- 展开更多
关键词 China builds Optical Fibre Tele-trunk network LINE
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Hubei: Building a Modern Communications Network
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《China Today》 2000年第10期22-25,共4页
关键词 CO building a Modern Communications network HUBEI
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乡村资产建设中行动者网络与社会企业家的作用
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作者 赵德余 《贵州大学学报(社会科学版)》 2025年第4期27-35,共9页
在乡村振兴战略背景下,如何驱动和激活各种潜在资源及其相关行动者网络以推动乡村资产建设和产业发展是乡村振兴的关键所在。在乡村建设过程中,特别是资产建设过程中,各种资源要素的激活关键在于对乡村行动者之间的网络关系的培育和激活... 在乡村振兴战略背景下,如何驱动和激活各种潜在资源及其相关行动者网络以推动乡村资产建设和产业发展是乡村振兴的关键所在。在乡村建设过程中,特别是资产建设过程中,各种资源要素的激活关键在于对乡村行动者之间的网络关系的培育和激活,这需要在形形色色的行动者之间形成从弱关系到强关系的各种协作机制。无论是资源要素的激活还是乡村建设中行动者网络关系的强化,这都需要一些核心或关键行动者的助推和催化剂作用,通常研究者会将这样的行动者称之为社会企业家。正如乡村振兴政策的驱动下,任何乡村产业发展在微观企业和村庄层面都是依靠一个个具体的社会企业家的助推才能获取成功和活力的。而政策工具的作用正是要引导和培育形形色色的社会企业家以助推乡村建设。 展开更多
关键词 资源要素 行动者网络 资产建设 乡村振兴 社会企业家
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Fault Diagnosis of an Intelligent Building Facility Using Bayesian Networks
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作者 ZHANG Qi-ding XU Jin-yu BAI Er-lei 《International Journal of Plant Engineering and Management》 2008年第1期26-31,共6页
There is great significance to diagnose the fault of an intelligent building facility for fault controlling, repairing, eliminating and preventing. As an example, this paper established a Bayesian networks model f or ... There is great significance to diagnose the fault of an intelligent building facility for fault controlling, repairing, eliminating and preventing. As an example, this paper established a Bayesian networks model f or fault diagnosis of the refrigeration system of an intelligent building facility, gave the networks parameters, and analyzed the reasoning mechanism. Based on the model, some data was analyzed and diagnosed by adopting Bayesian networks reasoning platform GeNIe. The result shows that the diagnosis effect is more comprehensive and reasonable than the other method. 展开更多
关键词 intelligent building facility refrigeration system fault diagnosis Bayesian networks
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基于大幅面SAM的遥感影像建筑物提取研究 被引量:1
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作者 赫晓慧 吴凯旋 +2 位作者 李盼乐 乔梦佳 程淅杰 《时空信息学报》 2025年第2期148-157,共10页
主流语义分割方法多针对小尺寸影像,而遥感影像通常覆盖地表范围广,现有研究在处理遥感影像时普遍面临分块拼接误差导致的空间特征关联性丢失与计算效率低等挑战。因此,基于SAM(segmentanything model),本文提出一种大幅面SAM(large sca... 主流语义分割方法多针对小尺寸影像,而遥感影像通常覆盖地表范围广,现有研究在处理遥感影像时普遍面临分块拼接误差导致的空间特征关联性丢失与计算效率低等挑战。因此,基于SAM(segmentanything model),本文提出一种大幅面SAM(large scale SAM,LS-SAM)遥感影像建筑物提取方法。首先,构建异构特征编码器来融合卷积神经网络局部提取能力与SAM全局提取优势,通过全局和局部信息的融合有效解决SAM局部特征表达不足问题;其次,设计空间多尺度Adapt Former模块,以增强SAM的多尺度特征提取能力,使得能够学习不同尺度的特征来提高语义分割的准确性;为了减少遥感影像处理过程中出现的内存占用过多和检索分块拼接所带来的误差,设置动态训练策略;最后,基于公开数据集进行验证,并与已有方法进行比较评价。结果表明,本文方法在数据集IAILD的表现优秀,在两种随机裁剪尺寸情况下,平均交并比呈现最优和次优;其中,在1024个像素×1024个像素尺寸时,m Io U达到86.5%,相较于BuildFormer的82.38%、SAM的76.98%,分别提升了3.12%、9.52%。 展开更多
关键词 深度学习 建筑物提取 SAM 位置编码生成器 CNN
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中小型互联网企业网络安全应急响应团队建设的探讨
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作者 郭旭敏 《山西电子技术》 2025年第5期93-96,共4页
互联网企业的业务模式多,涉及的产品也多,特别是互联网企业讲究“小步快跑敏捷迭代”,往往忽视了安全检查或来不及进行细致的安全检查,同时系统本身也存在安全漏洞,由于互联网业务的在线特性,使用互联网的人员都能接触到,相对于传统业... 互联网企业的业务模式多,涉及的产品也多,特别是互联网企业讲究“小步快跑敏捷迭代”,往往忽视了安全检查或来不及进行细致的安全检查,同时系统本身也存在安全漏洞,由于互联网业务的在线特性,使用互联网的人员都能接触到,相对于传统业务更容易受到攻击。为了尽可能减少损失,在发生安全事件后需要以最短的时间做出合理的响应,因此企业需要建立专门的应急响应团队。在分析现有的大型企业应急响应模式的基础上,针对没有应急响应机制的中小企业提出了两种模式供企业构建自己的应急响应团队。 展开更多
关键词 互联网企业 网络安全 应急响应 团队建设
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基于改进Unet++的双时相遥感图像建筑物损伤评估模型
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作者 于双双 康帅 +2 位作者 张建军 靳满 贺东青 《地球信息科学学报》 北大核心 2025年第11期2741-2755,共15页
【目的】为了对自然灾害发生后的快速响应与救援提供有力支持,针对建筑物遥感图像的损伤分类中出现的评估精度与效率不足的问题,提出一种基于两阶段卷积神经网络(BDDNET)的建筑物损伤评估模型。【方法】该模型以Unet++模型为基础,引入SE... 【目的】为了对自然灾害发生后的快速响应与救援提供有力支持,针对建筑物遥感图像的损伤分类中出现的评估精度与效率不足的问题,提出一种基于两阶段卷积神经网络(BDDNET)的建筑物损伤评估模型。【方法】该模型以Unet++模型为基础,引入SE、CBAM和ASPP模块,通过模块间的协同作用处理复杂背景与多尺度损伤区域,增强模型特征提取能力;同时,为应对数据集类别不平衡问题,采用CutMix数据增强技术,提升模型泛化能力与鲁棒性。实验采用xBD遥感卫星数据集具体分析了该方法的可行性,并通过消融实验证明了所添加模块的有效性,将评估指标与基于Unet++、FCN、Deeplabv3模型的结果进行了对比。【结果】实验验证显示,BDDNET模型在建筑物提取任务中的F1分数达到92.25%,IoU达到86.2%;在损伤分类任务中的F1分数达到76.55%,IoU达到64.15%。均较目前的主流模型均有一定程度的提升,能够有效完成建筑物提取与损伤分类任务。【结论】基于BDDNET的建筑物损伤评估模型,通过融合深度学习与遥感技术,结合模块优化与数据增强策略,显著提升了灾后建筑物损伤评估的精度与效率,具备良好的实用性与可靠性,可助力灾害后的快速响应与救援工作。 展开更多
关键词 建筑物损伤评估 遥感图像 Unet++ 双时相 卷积神经网络 建筑物提取 损伤分类
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群体感知工具对社会调节学习与协作知识建构的影响
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作者 马秀芳 王佳音 《电化教育研究》 北大核心 2025年第12期79-86,共8页
为探究群体感知工具促进协作学习效果的作用机制,研究选取50名研究生为研究对象,随机分为认知感知组、行为感知组和社会感知组,并对小组成员协作学习过程中产生的多模态数据进行认知网络分析和差异分析。研究发现三类群体感知工具分别... 为探究群体感知工具促进协作学习效果的作用机制,研究选取50名研究生为研究对象,随机分为认知感知组、行为感知组和社会感知组,并对小组成员协作学习过程中产生的多模态数据进行认知网络分析和差异分析。研究发现三类群体感知工具分别通过不同的路径作用于社会调节学习,并优化协作知识建构效能:认知感知工具通过可视化知识结构和认知差异,显著提升学习者的自我调节能力,促进个体的任务规划与元认知反思;行为感知工具借助行为追踪数据,驱动同伴间的调节行为,促使同伴之间及时反馈并优化协作流程;社会感知工具通过映射互动关系,增强群体协作中的责任分担与共识达成。 展开更多
关键词 群体感知工具 社会调节学习 协作知识建构 协作学习 认知网络分析
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基于数据图像化的装配式建筑施工安全评价研究 被引量:1
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作者 宋晓刚 赵东东 严晓东 《安全与环境学报》 北大核心 2025年第10期3715-3724,共10页
为降低装配式建筑在施工过程中的安全风险,提高施工安全管理水平,研究提出了一种基于数据图像化的深度学习安全评价方法。首先,从文献研究、事故案例两个方面对装配式建筑施工安全评价指标进行全面识别,并利用调查问卷法对其进行筛选,... 为降低装配式建筑在施工过程中的安全风险,提高施工安全管理水平,研究提出了一种基于数据图像化的深度学习安全评价方法。首先,从文献研究、事故案例两个方面对装配式建筑施工安全评价指标进行全面识别,并利用调查问卷法对其进行筛选,构建装配式建筑施工安全评价指标体系。其次,利用格拉姆角场(Gramian Angular Fields,GAF)将一维的安全评价数据转换成二维图像数据,增强离散序列特征的表征能力,进而构建卷积神经网络(Convolutional Neural Networks,CNN)对二维图像进行识别分类,实现对装配式建筑施工的安全等级的判别。最后,构建几种常见的机器学习评价方法并进行了对比。结果显示,评价方法准确率最高,显著优于传统的机器学习方法,可有效实现装配式建筑施工的安全评价。 展开更多
关键词 安全工程 装配式建筑 施工安全评价 格拉姆角场 卷积神经网络
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基于深度学习法的建筑结构裂缝检测 被引量:2
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作者 周旭文 《山西建筑》 2025年第8期53-57,共5页
文中首先对长短期记忆神经网络(Long Short-Term Memory,LSTM)深度学习的原理以及计算流程进行了介绍。而后基于建筑结构裂缝监测结果,采用长短期记忆神经网络建立了建筑结构的裂缝监测模型,且与BP神经网络模型的结果进行了比较。结果表... 文中首先对长短期记忆神经网络(Long Short-Term Memory,LSTM)深度学习的原理以及计算流程进行了介绍。而后基于建筑结构裂缝监测结果,采用长短期记忆神经网络建立了建筑结构的裂缝监测模型,且与BP神经网络模型的结果进行了比较。结果表明:LSTM算法在建筑物结构裂缝长度预测检测中具有显著的优越性,为建筑物结构裂缝检测预测提供了一种新思路。 展开更多
关键词 深度学习 LSTM神经网络 循环神经网络 建筑物裂缝
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