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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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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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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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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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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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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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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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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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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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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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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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城市建筑群抗震韧性集成评估方法
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作者 王威 龚玉涿 +2 位作者 朱峻佚 夏陈红 郭小东 《中国安全科学学报》 北大核心 2025年第4期219-226,共8页
为评估不同需求下城市建筑群抗震韧性,探索城市建筑群抗震韧性集成评估方法,利用树增强朴素贝叶斯网络(BN)方法构建BN模型,通过整合建筑类型、建造年代、结构类型等关键指标,快速预测不同目标地震下的建筑震害损伤状态;采用韧性指数法... 为评估不同需求下城市建筑群抗震韧性,探索城市建筑群抗震韧性集成评估方法,利用树增强朴素贝叶斯网络(BN)方法构建BN模型,通过整合建筑类型、建造年代、结构类型等关键指标,快速预测不同目标地震下的建筑震害损伤状态;采用韧性指数法、韧性要素等级法、风险韧性分析法和建筑群落韧性指标评价法4种韧性评估方法,集成评价北京市丰台区某街道群体建筑的抗震韧性,并对比分析各方法的优缺点及适用性。结果表明:韧性指数法适用于快速评估建筑恢复能力;韧性要素等级法便于直观显示建筑韧性等级;风险韧性分析法对灾害不确定性和随机性有较好处理能力;建筑群落韧性指标评价法则强调功能需求对综合评估的影响。 展开更多
关键词 城市建筑群 抗震韧性 集成评估 损伤状态 贝叶斯网络(BN)
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装配式建筑施工安全风险因素耦合分析:N-K修正复杂网络
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作者 窦玉丹 闫学涯 《安全与环境学报》 北大核心 2025年第9期3425-3435,共11页
为定量揭示装配式建筑施工安全风险特性,识别关键风险因素并实现对事故的主动干预,基于N-K模型修正的复杂网络进行风险耦合分析。首先,收集国内外407起事故案例,结合事故致因理论识别出4个子系统与23个风险因素。然后,在宏观角度上通过... 为定量揭示装配式建筑施工安全风险特性,识别关键风险因素并实现对事故的主动干预,基于N-K模型修正的复杂网络进行风险耦合分析。首先,收集国内外407起事故案例,结合事故致因理论识别出4个子系统与23个风险因素。然后,在宏观角度上通过N-K模型分析不同系统间的风险耦合情况,计算风险耦合信息值;在微观角度通过Apriori算法定量挖掘频繁项集,揭示因素间的潜在关联关系,并构建风险因素的复杂网络。最后,基于节点中心度分析与可达性分析,探究风险因素的作用机制,将N-K模型计算值作为权重值,对节点接近中心度值进行耦合修正,识别关键风险因素,并提出针对性的干预建议。结果表明:环-管系统间存在较强的耦合作用,显著增加装配式建筑施工安全事故风险发生的可能性。干预“管理失效”与“人的不安全行为”维度中相关因素有助于减少风险事故发生。同时,现场信息沟通、交叉作业安全和施工自然环境等是导致事故发生的关键因素,需重点防范。 展开更多
关键词 安全工程 装配式建筑 风险因素 N-K模型 复杂网络 耦合分析
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一体成链:统一大市场建设对企业国内供应链网络的影响
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作者 罗长远 彭湛川 陈智韬 《国际商务研究》 北大核心 2025年第6期1-23,共23页
本文考察了在推进区域协调发展和构建全国统一大市场的战略背景下,市场一体化对企业跨地区供应链网络的影响。首先,构建了一个引入供应链关系内生调整的理论框架,揭示了统一大市场如何通过降低交易成本和提升匹配效率进而优化企业间的... 本文考察了在推进区域协调发展和构建全国统一大市场的战略背景下,市场一体化对企业跨地区供应链网络的影响。首先,构建了一个引入供应链关系内生调整的理论框架,揭示了统一大市场如何通过降低交易成本和提升匹配效率进而优化企业间的供应链合作。然后,在此基础上,构建了2013~2021年的“供应商—客户—年份”三维面板数据,并以省际市场一体化指数作为代理变量,采用工具变量法等策略进行因果关系识别。研究发现,统一大市场建设显著提升了企业跨地区构建供应链关系的概率。机制分析进一步发现,该效应主要通过两条渠道实现:一是成本机制,即通过促进商品和要素的跨地区流动以降低供应链合作成本;二是风险机制,即通过缓解断链风险以增强供应链关系韧性。本文的研究有助于深化对国内大循环背景下供应链网络重构的理解,为统一大市场体制机制的优化提供理论支持和经验证据。 展开更多
关键词 统一大市场建设 市场一体化 供应链网络
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改进CycleGAN的半监督建筑物提取算法
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作者 卢鹏 仲闯 《计算机工程》 北大核心 2025年第3期241-251,共11页
建筑物提取需要大量的标注数据进行训练,收集和标注数据需要耗费大量时间。为了在小样本遥感图像数据集上基于半监督学习实现建筑物提取的目的,构建4组建筑物提取数据集,提出了一种基于循环一致性生成对抗网络(CycleGAN)的建筑物提取算... 建筑物提取需要大量的标注数据进行训练,收集和标注数据需要耗费大量时间。为了在小样本遥感图像数据集上基于半监督学习实现建筑物提取的目的,构建4组建筑物提取数据集,提出了一种基于循环一致性生成对抗网络(CycleGAN)的建筑物提取算法。首先,在生成器中引入全局注意力机制(GAM)以增强对建筑物和图像背景细节特征的区分;其次,在判别器中加入谱归一化层以增强训练稳定性,解决了训练过程中梯度消失问题;最后,改进对抗损失和循环一致性损失以提高生成图像的质量,避免生成图像的过度平滑化,并引入Identity损失以限制生成器不会自主修改输入图像的颜色,保证输入图像与输出图像颜色组成的一致性。实验结果表明,在第1组小样本数据集上,与UNIT、MUNIT、U-GAT-IT、SPatchGAN、QS-Attn模型进行半监督实验对比,结构相似性(SSIM)值和准确率分别至少提高了3、8.1百分点,在扩充数据规模的数据集上,使用改进后的算法进行全监督和半监督实验对比,验证了改进后的算法在小样本遥感图像数据集上实现建筑物半监督提取的有效性。 展开更多
关键词 建筑物提取 循环一致性生成对抗网络 谱归一化 全局注意力机制 半监督
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