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Revisiting multi-region 16S sequencing in gastric cancer
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作者 Liu Luo Gang Huang +1 位作者 Hua Yang Hao Chi 《World Journal of Gastrointestinal Oncology》 2026年第1期15-19,共5页
Wu et al recently applied multi-region 16S rRNA sequencing to characterize the gastric cancer microbiome,demonstrating improved taxonomic resolution and detection sensitivity over conventional single-region approaches... Wu et al recently applied multi-region 16S rRNA sequencing to characterize the gastric cancer microbiome,demonstrating improved taxonomic resolution and detection sensitivity over conventional single-region approaches.While the study represents a valuable methodological step forward,it remains limited by singlecenter design,lack of quantitative calibration,and insufficient control for contamination and inter-laboratory variability.This editorial critically appraises these methodological gaps and emphasizes that future efforts must focus on harmonized,consensus-driven workflows to ensure reproducibility and clinical reliability.The translational potential of multi-region 16S lies in moving from descriptive microbial profiling to actionable clinical integration,particularly for recurrence prediction,treatment-response monitoring,and perioperative complication risk assessment.By addressing these methodological,economic,and ethical challenges,the field can advance toward evidence-based and clinically deployable microbiome-guided precision oncology. 展开更多
关键词 Gastric cancer MICROBIOME multi-region 16S rRNA sequencing METAGENOMICS Biomarkers Prognosis Immune microenvironment Precision oncology
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Effectiveness of multi-region 16S rRNA gene sequencing in studying the microbiome of gastric cancer tissues 被引量:1
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作者 Ting-Ting Wu Xiang Zhou +1 位作者 Qi Huang Qi Yang 《World Journal of Gastrointestinal Oncology》 2025年第10期261-268,共8页
BACKGROUND The gastric microbiome is closely associated with gastric cancer,and single-region 16S rRNA sequencing has limitations in analyzing its characteristics,necessitating the search for a better sequencing metho... BACKGROUND The gastric microbiome is closely associated with gastric cancer,and single-region 16S rRNA sequencing has limitations in analyzing its characteristics,necessitating the search for a better sequencing method.AIM To evaluate the effectiveness of multi-region 16S rRNA gene sequencing in studying the microbiome of gastric cancer tissues.METHODS Patients with gastric cancer(n=118)who underwent surgery at Liyang People's Hospital from January 2022 to December 2024 were enrolled.Fifty-nine paraffinembedded and 59 fresh tissue samples were obtained.The ZymoBIOMICSTM microbial community standard and Escherichia coli ATCC 25922 were used as positive controls.Multi-region and single-region 16S rRNA gene sequencing were performed.Species identification,detection rates at varying microbial abundances,operational taxonomic unit(OTU)counts,and alpha diversity indices in gastric cancer tissues were compared between the two methods.RESULTS Multi-region 16S rRNA sequencing identified more species(eight species and eight genera)in the positive controls compared with single-region sequencing(one species and six genera).Detection rates at concentrations of 103,102,and 10 CFU/mg were significantly higher using multi-region sequencing(P<0.05).Multi-region sequencing also revealed significantly higher OTU counts and alpha diversity indices(Shannon,Simpson,and Chao1)in gastric cancer tissues(P<0.05).CONCLUSION Compared with single-region sequencing,multi-region 16S rRNA gene sequencing demonstrates superior species resolution and detection sensitivity,providing a more comprehensive profile of microbial diversity in gastric cancer tissues. 展开更多
关键词 16S rRNA gene multi-region sequencing Gastric cancer Species resolution MICROBIOME Alpha diversity
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MULTI-REGION SEGMENTATION OF SAR IMAGE BY A MULTIPHASE LEVEL SET APPROACH 被引量:2
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作者 Fu Yusheng Cao Zongjie Pi Yiming 《Journal of Electronics(China)》 2008年第4期556-561,共6页
In this letter,a multiphase level set approach unifying region and boundary-based infor-mation for multi-region segmentation of Synthetic Aperture Radar(SAR)image is presented.Anenergy functional that is applicable fo... In this letter,a multiphase level set approach unifying region and boundary-based infor-mation for multi-region segmentation of Synthetic Aperture Radar(SAR)image is presented.Anenergy functional that is applicable for SAR image segmentation is defined.It consists of two termsdescribing the local statistic characteristics and the gradient characteristics of SAR image respectively.A multiphase level set model that explicitly describes the different regions in one image is proposed.The purpose of such a multiphase model is not only to simplify the way of denoting multi-region by levelset but also to guarantee the accuracy of segmentation.According to the presented multiphase model,the curve evolution equations with respect to edge curves are deduced.The multi-region segmentationis implemented by the numeric solution of the partial differential equations.The performance of theapproach is verified by both simulation and real SAR images.The experiments show that the proposedalgorithm reduces the speckle effect on segmentation and increases the boundary alignment accuracy,thus correctly divides the multi-region SAR image into different homogenous regions. 展开更多
关键词 Synthetic Aperture Radar (SAR) SEGMENTATION multi-region Multiphase level set
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New SOI power device with multi-region high-concentration fixed interface charge and the model of breakdown voltage
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作者 李琦 李海鸥 +2 位作者 唐宁 翟江辉 宋树祥 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第3期308-312,共5页
A new SOI power device with multi-region high-concentration fixed charge(MHFC) is reported. The MHFC is formed through implanting Cs or I ion into the buried oxide layer(BOX), by which the high-concentration dynam... A new SOI power device with multi-region high-concentration fixed charge(MHFC) is reported. The MHFC is formed through implanting Cs or I ion into the buried oxide layer(BOX), by which the high-concentration dynamic electrons and holes are induced at the top and bottom interfaces of BOX. The inversion holes can enhance the vertical electric field and raise the breakdown voltage since the drain bias is mainly generated from the BOX. A model of breakdown voltage is developed, from which the optimal spacing has also been obtained. The numerical results indicate that the breakdown voltage of device proposed is increased by 287% in comparison to that of conventional LDMOS. 展开更多
关键词 multi-region high-concentration fixed interface charge model of breakdown voltage
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Coordinated Planning of Interconnected Multi-Regional Power Systems Considering Large-Scale Energy Storage Systems, Transmission Expansion, and Carbon Emission Quota Trading
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作者 Jia Liu Biao Jiang +4 位作者 Zao Tang Pingliang Zeng Tong Su Yalou Li Qiuwei Wu 《CSEE Journal of Power and Energy Systems》 2025年第2期490-502,共13页
Global warming has motivated the world’s majorcountries to actively develop technologies and make policies topromote carbon emission reduction. Focusing on interconnectedmulti-regional power systems, this paper propo... Global warming has motivated the world’s majorcountries to actively develop technologies and make policies topromote carbon emission reduction. Focusing on interconnectedmulti-regional power systems, this paper proposes a coordinatedplanning model for interconnected power systems consideringenergy storage system planning and transmission expansion. Amarket-based carbon emission quota trading market that helpsreduce carbon emissions is built and integrated into the coordinated planning model, where entities can purchase extra or sellsurplus carbon emission quotas. Its effects on promoting carbonemission reduction are analyzed. Considering the limitations oninformation exchange between interconnected regional powersystems, the proposed model is decoupled and solved with theanalytical target cascading algorithm. A modified two-region 48-bus system is used to verify the effectiveness of the proposedmodel and solving method. 展开更多
关键词 Analytical target cascading algorithm energy storage system multi-regional power system tiered pricing mechanism transmission expansion planning
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成渝双城经济圈建设下“万达开”旅游协同发展的政策支持与实践路径
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作者 刘江 李京朋 《四川旅游学院学报》 2026年第1期48-61,共14页
文章以“万达开”区域(万州、达州、开州)为研究对象,探讨其旅游协同发展的理论基础、现状问题及实现路径。首先,基于区域协调均衡发展理论,分析“万达开”区域在文旅资源布局、产业协同、基础设施互联互通、公共服务共享等方面面临的挑... 文章以“万达开”区域(万州、达州、开州)为研究对象,探讨其旅游协同发展的理论基础、现状问题及实现路径。首先,基于区域协调均衡发展理论,分析“万达开”区域在文旅资源布局、产业协同、基础设施互联互通、公共服务共享等方面面临的挑战,包括区域发展不均衡、产品同质化严重、协同机制不完善等问题。其次,提出构建区域文旅协同发展体制机制的原则与结构。从品牌统一建设、产品错位开发、智慧平台打造与生态优先治理等维度,系统阐述“万达开”区域深化文旅协同发展的策略路径。研究旨在为成渝地区双城经济圈北翼构建国家级文旅协同发展示范区提供理论支撑与实践参考。 展开更多
关键词 万达开 文旅协同发展 品牌建设 多级治理
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基于遥感土壤湿度数据的分布式水文模型参数联合率定方法
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作者 李致家 邓帆 +1 位作者 张汉辰 李安琪 《河海大学学报(自然科学版)》 北大核心 2026年第1期1-7,共7页
为探究在半干旱小流域引入遥感土壤湿度数据辅助分布式水文模型参数率定的可行性,提出了融合硬数据(流量)与软数据(遥感土壤湿度)的参数联合率定方法。该方法将CLDAS卫星遥感土壤湿度数据应用于Grid-Multi-GA模型中,采用多目标优化框架... 为探究在半干旱小流域引入遥感土壤湿度数据辅助分布式水文模型参数率定的可行性,提出了融合硬数据(流量)与软数据(遥感土壤湿度)的参数联合率定方法。该方法将CLDAS卫星遥感土壤湿度数据应用于Grid-Multi-GA模型中,采用多目标优化框架,以流量模拟的纳什效率系数和土壤湿度时空分布的Spearman相关系数作为双评价指标,通过系统调整权重实现两类指标的动态权衡,最终确定最优权重及其对应的产流和汇流参数组合,同时通过设置参数未率定、仅用流量率定、流量与土壤湿度联合率定3种情景,验证联合率定方法的可行性。宁夏原州流域的实例验证结果表明:流量与土壤湿度联合率定的Grid-Multi-GA模型在小流域中的洪水模拟中,纳什效率系数大于0.7,Spearman相关系数为0.84,明显优于未率定和仅用流量率定的Grid-Multi-GA模型。 展开更多
关键词 半干旱地区 Grid-Multi-GA模型 参数率定 径流模拟 遥感土壤湿度 原州流域
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人工智能赋能基础教育:政策供给、现状考量与多维进路
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作者 郭喜永 范肖肖 《现代教育科学》 2026年第1期21-27,51,共8页
《教育强国建设规划纲要(2024-2035年)》提出了“促进人工智能助力教学变革”的时代要求,将人工智能赋能教育发展上升为国家战略。建设教育强国,基点在基础教育。为充分释放人工智能对基础教育高质量发展的赋能价值,基于文献分析、案例... 《教育强国建设规划纲要(2024-2035年)》提出了“促进人工智能助力教学变革”的时代要求,将人工智能赋能教育发展上升为国家战略。建设教育强国,基点在基础教育。为充分释放人工智能对基础教育高质量发展的赋能价值,基于文献分析、案例研究与比较研究方法,系统梳理国家与省级层面“人工智能+教育”政策演进脉络,深度剖析北京、上海等六座代表性城市的区域实践模式、特色经验与实施成效,结合国际先进经验,全面检视制度、实践、主体三大维度的现实梗阻。同时,从资源供给、教学范式、师资培育、伦理治理、协同保障五个维度,提出推进人工智能赋能基础教育的多维进路。 展开更多
关键词 人工智能 基础教育 政策供给 区域实践 多维进路
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苏南城镇碳汇空间时空演变与多情景模拟
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作者 范凌云 汤宇轩 田永兵 《风景园林》 北大核心 2026年第1期23-33,共11页
【目的】为保护并优化高度城镇化地区的碳汇空间,有必要系统研究其时空演变特征及规律。【方法】本研究聚焦苏南地区“城镇尺度”的碳汇空间,在研究其时空演变特征的基础上,结合斑块生成土地利用变化模拟(patch-generating land use sim... 【目的】为保护并优化高度城镇化地区的碳汇空间,有必要系统研究其时空演变特征及规律。【方法】本研究聚焦苏南地区“城镇尺度”的碳汇空间,在研究其时空演变特征的基础上,结合斑块生成土地利用变化模拟(patch-generating land use simulation,PLUS)模型和聚类分析法研判不同城镇综合响应状态,并提出差异化的碳汇空间管控策略。【结果】1)2000—2020年苏南地区碳汇空间面积大幅减少,减少区域高度集中于高价值碳汇空间。碳汇空间格局在城镇尺度上未因城镇化而全面瓦解,表现出较强的稳定性。2)通过对自然增长情景、碳汇保护情景、碳汇强化情景3种情景的模拟,发现加大碳汇空间保护力度能够实现高质量碳汇空间扩张,但需要警惕生态功能单一化风险,避免盲目追求“高碳汇系数”。3)在3种模拟情景下,大部分城镇碳汇空间结构较稳定,建议通过存量挖潜与功能置换等方式优化碳汇空间;而部分敏感型城镇则呈现差异化演变路径,需根据其具体风险类型,实施更具针对性的管控策略。【结论】快速城镇化地区碳汇空间面积虽然呈现缩减趋势,但在城镇尺度表现出稳定性与敏感性共存的特征。这一特性可通过多情景模拟研判,从而为制定差异化的城镇碳汇空间管控策略提供科学依据。 展开更多
关键词 风景园林 碳汇空间 PLUS模型 多情景模拟 苏南地区 城镇尺度
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Demand-driven water withdrawals by Chinese industry: a multi-regional input-output analysis 被引量:6
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作者 Bo ZHANG Z. M. CHEN +2 位作者 L. ZENG H. QIAO B. CHEN 《Frontiers of Earth Science》 SCIE CAS CSCD 2016年第1期13-28,共16页
With ever increasing water demands and the continuous intensification of water scarcity arising from China's industrialization, the country is struggling to harmonize its industrial development and water supply. This... With ever increasing water demands and the continuous intensification of water scarcity arising from China's industrialization, the country is struggling to harmonize its industrial development and water supply. This paper presents a systems analysis of water with- drawals by Chinese industry and investigates demand- driven industrial water uses embodied in final demand and interregional trade based on a multi-regional input-output model. In 2007, the Electric Power, Steam, and Hot Water Production and Supply sector ranks first in direct industrial water withdrawal (DWW), and Construction has the largest embodied industrial water use (EWU). Investment, consumption, and exports contribute to 34.6%, 33.3%, and 30.6% of the national total EWU, respectively. Specifically, 58.0%, 51.1%, 48.6%, 43.3%, and 37.5% of the regional EWUs respectively in Guangdong, Shanghai, Zhejiang, Jiangsu, and Fujian are attributed to international exports. The total interregional import/export of embodied water is equivalent to about 40% of the national total DWW, of which 55.5% is associated with the DWWs of Electric Power, Steam, and Hot Water Production and Supply. Jiangsu is the biggest interregional exporter and deficit receiver of embodied water, in contrast to Guangdong as the biggest interregional importer and surplus receiver. Without implementing effective water- saving measures and adjusting industrial structures, the regional imbalance between water availability and water demand tends to intensify considering the water impact of domestic trade of industrial products. Steps taken to improve water use efficiency in production, and to enhance embodied water saving in consumption are both of great significance for supporting China's water policies. 展开更多
关键词 water withdrawal embodied water use Chinese industry interregional trade multi-regional inputoutput analysis
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Multi-regional input-output analysis for China's regional CH4 emissions 被引量:3
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作者 Bo ZHANG Jiashuo LI Beihua PENG 《Frontiers of Earth Science》 SCIE CAS CSCD 2014年第1期163-180,共18页
China is the largest CH4 emitter in the world. Given the importance of CH4 in greenhouse gas emission inventories, the characteristics ofChina's CH4 emissions at different scales deserve to be fully understood. Prese... China is the largest CH4 emitter in the world. Given the importance of CH4 in greenhouse gas emission inventories, the characteristics ofChina's CH4 emissions at different scales deserve to be fully understood. Presented in this paper is an interprovincial input output embodi- ment analysis of China's regional CH4 emissions in 2007, based on the most recently available multi-regional input- output table, and relevant CH4 emissions data. The results show that the eastern, central and western areas contribute to 48.2%, 28.6%, and 23.3% of the national total embodied emissions, respectively. Guangdong has the highest level of embodied CH4 emissions among all of the 30 regions. The Agriculture sector produces the most embodied CH4 emissions in final demand, followed by the Construction, Food Production and Tobacco Processing, and Other Service Activities sectors. Significant net transfers of embodied CH4 emission flows are identified from the central and western areas to the eastern area via interregional trade. Shanxi is the largest interregional exporter of embodied CH4 emissions. In contrast, Guangdong is the largest interregional importer. Energy activities, agricultural activities, and waste management comprise 65.6%, 30.7%, and 3.7% of the total embodied CH4 emissions in interregional trade, respectively. By using consumption-based accounting principles, the emis- sion magnitudes, per capita emissions, and emission intensities of most eastern regions increase remarkably, while those of some central and western regions decrease largely. To achieve regional CH4 emission mitigation, comprehensive mitigation measures should be designed under consideration of regional transfer of emission responsibility. 展开更多
关键词 China's CH4 emissions multi-regional input-output analysis consumption-based emission accounting
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A new epidemic modeling approach:Multi-regions discrete-time model with travel-blocking vicinity optimal control strategy 被引量:2
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作者 Omar Zakary Mostafa Rachik Ilias Elmouki 《Infectious Disease Modelling》 2017年第3期304-322,共19页
First,we devise in this paper,a multi-regions discrete-time model which describes the spatial-temporal spread of an epidemic which starts from one region and enters to regions which are connected with their neighbors ... First,we devise in this paper,a multi-regions discrete-time model which describes the spatial-temporal spread of an epidemic which starts from one region and enters to regions which are connected with their neighbors by any kind of anthropological movement.We suppose homogeneous Susceptible-Infected-Removed(SIR)populations,and we consider in our simulations,a grid of colored cells,which represents the whole domain affected by the epidemic while each cell can represent a sub-domain or region.Second,in order to minimize the number of infected individuals in one region,we propose an optimal control approach based on a travel-blocking vicinity strategy which aims to control only one cell by restricting movements of infected people coming from all neighboring cells.Thus,we show the influence of the optimal control approach on the controlled cell.We should also note that the cellular modeling approach we propose here,can also describes infection dynamics of regions which are not necessarily attached one to an other,even if no empty space can be viewed between cells.The theoretical method we follow for the characterization of the travel-locking optimal controls,is based on a discrete version of Pontryagin's maximum principle while the numerical approach applied to the multi-points boundary value problems we obtain here,is based on discrete progressive-regressive iterative schemes.We illustrate our modeling and control approaches by giving an example of 100 regions. 展开更多
关键词 multi-regions model SIR epidemic model Discrete-time model Optimal control VICINITY Travel-blocking
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“一带一路”沿线经济体贸易隐含碳网络及其动态演化机制
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作者 罗明 郑锐豪 范如国 《生态经济》 北大核心 2026年第2期108-115,共8页
利用多区域投入产出模型对“一带一路”沿线经济体贸易隐含碳进行测度,并构建贸易隐含碳网络,采用时间指数随机图模型探究空间关联特征及内生演化机制。研究表明:(1)网络结构稳定,呈现出“小世界”和“中心—边缘”特征。(2)贸易隐含碳... 利用多区域投入产出模型对“一带一路”沿线经济体贸易隐含碳进行测度,并构建贸易隐含碳网络,采用时间指数随机图模型探究空间关联特征及内生演化机制。研究表明:(1)网络结构稳定,呈现出“小世界”和“中心—边缘”特征。(2)贸易隐含碳规模不断增大,交流日益频繁。互惠性主要存在于发达经济体板块内部;发达经济体和落后经济体之间的对称可达性较弱,存在不平等的碳排放关系。(3)网络形成和演化存在结构依赖和时间依赖效应。其中,聚敛性、多连通性、三元传递闭合性和路径依赖效应明显;发送者的出口污染密度以及接收者的经济发展水平与贸易隐含碳关系的形成概率呈正相关关系,而接收者的环境监管力度与贸易隐含碳关系的形成概率呈负相关关系;贸易隐含碳关系随着不断深化的中间品贸易而增强。 展开更多
关键词 多区域投入产出模型 贸易隐含碳网络 时间指数随机图模型 内生演化机制
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融合定位图与上下文感知的伪装目标检测网络
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作者 余肖生 陈灿 +1 位作者 李旭 陈鹏 《计算机科学与探索》 北大核心 2026年第1期217-227,共11页
基于区域先验的伪装目标检测(COD)模型通常在早期阶段提取目标在图像中的位置信息,通过将目标的位置信息与图像特征相结合,网络能够更加有效地聚焦于目标区域,从而提高检测精度。而在许多具有挑战性的场景中,当前伪装目标检测算法对目... 基于区域先验的伪装目标检测(COD)模型通常在早期阶段提取目标在图像中的位置信息,通过将目标的位置信息与图像特征相结合,网络能够更加有效地聚焦于目标区域,从而提高检测精度。而在许多具有挑战性的场景中,当前伪装目标检测算法对目标位置信息的提取能力有限,从而导致区域先验不准确甚至目标缺失。为此,提出了一种融合定位图与上下文感知的伪装目标检测网络FLMCA-Net。构建定位模块融合来自主干网络的多尺度特征并从全局、局部两个维度上提取目标的位置信息;设计了感受野增强模块细化不同尺度的特征表示;引入上下文感知融合模块将多尺度特征和目标区域先验充分交互融合并挖掘目标的全局上下文特征。在3个公开数据集上的实验表明,FLMCA-Net相较于其他20种代表性模型均取得了最优表现,比RISNet在S_(α)、E_(ϕ)和F_(β)^(ω)方面的性能平均提升了2.5%、1.8%和3.6%。 展开更多
关键词 伪装目标检测 上下文信息 区域先验 多尺度特征
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基于多特征融合的丘陵—坝区过渡带高标准农田遥感提取
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作者 杨仙瑜 张家琦 +2 位作者 刘素红 张立强 李益敏 《农业工程学报》 北大核心 2026年第1期191-200,共10页
为实现丘陵—坝区过渡带高标准农田的精准识别,提出一种融合区域特征的多维特征遥感提取方法。以云南德宏州章凤镇为研究区,基于哨兵二号与高分二号影像,构建包含光谱特征(10个波段)、光谱指数(归一化植被指数(normalized difference ve... 为实现丘陵—坝区过渡带高标准农田的精准识别,提出一种融合区域特征的多维特征遥感提取方法。以云南德宏州章凤镇为研究区,基于哨兵二号与高分二号影像,构建包含光谱特征(10个波段)、光谱指数(归一化植被指数(normalized difference vegetation index,NDVI)、比值植被指数(ratio vegetation index,RVI)、归一化水体指数(normalized difference water index,NDWI)、优化型土壤调节植被指数(optimized soil adjusted vegetation index,OSAVI))、物候特征(返青期start of season,SOS_DOY;收割期end of season,EOS_DOY;生长季长度length of growing season,LOS_days)与区域特征(斑块密度、沟渠密度、坡度)在内的20维特征集。采用随机森林(random forests,RF)与XGBoost两种机器学习算法,设计S1(光谱)、S2(光谱+光谱指数)、S3(光谱+物候特征)、S4(光谱+区域特征)及S5(全特征)5组组合方案,系统评估各特征组合对高标准农田识别的贡献,并揭示其空间分布格局。结果表明:1)区域特征的引入显著提升了分类精度,斑块密度和沟渠密度是高标准农田识别的关键指标;2)全特征方案S5分类精度最高,且XGBoost的分类性能整体优于RF;3)高标准农田在沟渠300 m缓冲带(占83.13%)、坡度<15°区(占84.43%)高度集聚。该研究通过引入区域特征有效提升了高标准农田的识别精度,为复杂地区高精度识别提供技术支撑。 展开更多
关键词 高标准农田 多维特征融合 区域特征 随机森林 XGBoost 丘陵—坝区过渡带 空间格局
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Cutting CO_(2)emissions through demand side regulation:Implications from multi-regional input-output linear programming model
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作者 Nan LIU Jidong KANG +1 位作者 Tsan Sheng NG Bin SU 《Frontiers of Engineering Management》 2022年第3期452-461,共10页
This study combines multi-regional inputoutput(MRIO)model with linear programming(LP)model to explore economic structure adjustment strategies for the reduction of carbon dioxide(CO_(2))emissions.A particular feature ... This study combines multi-regional inputoutput(MRIO)model with linear programming(LP)model to explore economic structure adjustment strategies for the reduction of carbon dioxide(CO_(2))emissions.A particular feature of this study is the identification of the optimal regulation sequence of final products in various regions to reduce CO_(2)emissions with the minimum loss in gross domestic product(GDP).By using China's MRIO tables 2017 with 28 regions and 42 economic sectors,results show that reduction in final demand leads to simultaneous reductions in GDP and CO_(2)emissions.Nevertheless,certain demand side regulation strategy can be adopted to lower CO_(2)emissions at the smallest loss of economic growth.Several key final products,such as metallurgy,nonmetal,metal,and chemical products,should first be regulated to reduce CO_(2)emissions at the minimum loss in GDP.Most of these key products concentrate in the coastal developed regions in China.The proposed MRIO-LP model considers the inter-relationship among various sectors and regions,and can aid policy makers in designing effective policy for industrial structure adjustment at the regional level to achieve the national environmental and economic targets. 展开更多
关键词 CO_(2)emissions demand side regulation multi-regional input-output model linear programming model
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电力传输网多区域分布式协同控制方法仿真
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作者 李辉 李旭 +2 位作者 刘宇明 罗思洋 陈文专 《电子设计工程》 2026年第2期154-158,共5页
在电力传输网多区域运行环境中,因分布式电源渗透率攀升、负荷动态异质化及复杂非线性耦合等因素,导致系统频率失稳等问题频发。为此,进行了电力传输网多区域分布式协同控制方法仿真研究。通过获取非线性不确定鲁棒分布式协调变量,设计... 在电力传输网多区域运行环境中,因分布式电源渗透率攀升、负荷动态异质化及复杂非线性耦合等因素,导致系统频率失稳等问题频发。为此,进行了电力传输网多区域分布式协同控制方法仿真研究。通过获取非线性不确定鲁棒分布式协调变量,设计自适应鲁棒控制协议,利用协调变量融合全局约束与区域间信息,有效抑制系统非线性项与未知干扰。构建包含协调变量的多区域协同控制仿真模型,设计多区域协同控制策略,实现全局约束与分布式决策的有机融合,从而达成电力传输网多区域分布式协同控制。仿真实验表明,该方法控制频率波动范围稳定在限定范围47.6~48.4 Hz内,且在相同时段内母线电压与标准电压一致,分别为520 kV(09:00—12:00)、580 kV(06:00—09:00与12:00—18:00),有效提升了对动态拓扑与复杂场景的适应能力。 展开更多
关键词 电力传输网 多区域 分布式协同控制 协调变量 鲁棒控制
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基于PLUS-InVEST模型的川渝地区碳储量变化及多情景预测
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作者 陈红香 辛存林 +4 位作者 陈宁 马新淑 白元 康利刚 辛顺杰 《环境科学》 北大核心 2026年第1期360-371,共12页
陆地生态系统的碳储量受土地利用/覆盖变化(LUCC)的影响显著,探讨LUCC对区域陆地生态系统碳储量的作用,对于改进土地利用结构和实现碳达峰及碳中和目标具有极其重要的意义.研究利用2000~2020年间的土地利用数据,综合考虑了13项关键驱动... 陆地生态系统的碳储量受土地利用/覆盖变化(LUCC)的影响显著,探讨LUCC对区域陆地生态系统碳储量的作用,对于改进土地利用结构和实现碳达峰及碳中和目标具有极其重要的意义.研究利用2000~2020年间的土地利用数据,综合考虑了13项关键驱动因素,建立了自然发展(ND)、生态保护(EP)、经济发展(ED)和综合发展(CD)这4种发展情景.结合PLUS和InVEST模型,模拟了川渝地区土地利用类型的动态调整与碳储量的时空演变.结果表明:(1)2000~2020年,草地和耕地面积分别减少了83.65×10^(4) hm^(2)和46.41×10^(4) hm^(2),而林地、建设用地和水域面积则分别增加了65.37×10^(4)、50.55×10^(4)和13.41×10^(4) hm^(2),未利用地面积基本保持稳定.(2)在2000年、2010年和2020年,碳储量分别为1 968.88×10^(7)、1 996.90×10^(7)和1 998.59×10^(7) t,总碳储量增加了29.71×10^(7) t,耕地和草地向林地的转变是碳储量增加的主要因素.(3)相较于2020年,ND、ED、EP和CD情景下的碳储量分别增加1.48×10^(7)、27.75×10^(7)、43.62×10^(7)和50.32×10^(7) t.在CD情景下,碳储量及其总价值均超过其他情景,是最优的发展模式.研究结果从土地利用的角度为生态系统碳储量优化决策提供参考,这将为未来土地利用政策的制定以及“双碳”战略目标的实现提供有力支持. 展开更多
关键词 土地利用/覆盖变化(LUCC) 碳储量 PLUS-InVEST模型 多情景预测 川渝地区
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基于既有铁路运行图的市域列车加线方法研究
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作者 张宇 汤杰 《现代城市轨道交通》 2026年第1期106-111,共6页
为合理利用既有铁路资源开行市域列车,在保障市域列车服务频率的同时减少加线列车对既有运行图的影响,以既有铁路运行图为基础,通过事件活动图构建运行图的抽象化拓扑结构,分析总结市域列车加线要点。研究构建多目标线性规划模型,以最... 为合理利用既有铁路资源开行市域列车,在保障市域列车服务频率的同时减少加线列车对既有运行图的影响,以既有铁路运行图为基础,通过事件活动图构建运行图的抽象化拓扑结构,分析总结市域列车加线要点。研究构建多目标线性规划模型,以最大化市域列车开行数量、最小化既有列车调整时间为目标,以列车区间运行时间、停站时间及安全间隔等为约束,实现基于既有铁路运行图的市域列车加线优化。以杭甬铁路宁波至绍兴段为研究对象,开展不同场景下的算例分析,结果表明,该模型可在有效控制既有列车调整幅度的基础上,实现市域列车加线问题的求解,对相关部门利用既有铁路开行市域列车的运营决策具有重要指导意义。 展开更多
关键词 市域列车 运行图 多目标线性规划 加线模型 事件活动图
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基于MAS的梯田非粮化农户行为决策机制与模拟
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作者 后莉 裴婷婷 +2 位作者 陈英 谢保鹏 席瑞云 《农业资源与环境学报》 北大核心 2026年第1期104-117,共14页
为探究农户梯田非粮化行为运行逻辑,本研究选取3个典型研究区:果粮复合型(区1)、粮作撂荒混合型(区2)、苹果主导型(区3),基于多智能体系统(MAS),结合实地调研和多情景模拟,探究了甘肃陇中陇东地区农户在梯田利用决策中的行为机制。结果... 为探究农户梯田非粮化行为运行逻辑,本研究选取3个典型研究区:果粮复合型(区1)、粮作撂荒混合型(区2)、苹果主导型(区3),基于多智能体系统(MAS),结合实地调研和多情景模拟,探究了甘肃陇中陇东地区农户在梯田利用决策中的行为机制。结果表明:农户梯田利用行为决策的内在机制是以追求经济效益最大化为主要目标,由家庭资源禀赋产生更强的限制和指导作用,外部自然、社会、政策环境提供额外激励或约束的过程,其中,三个研究区内外部环境变量组合权重比值分别为:0.486∶0.514、0.575∶0.425和0.538∶0.462。陇中陇东地区农户梯田利用决策行为呈现以非粮利用为主导、粮食生产为辅的趋势,三个研究区非粮化利用最终决策值分别为0.852、0.842、0.942。研究区农户对各梯田利用方式感知度、反馈值、决策值及主要环境变量具有空间异质性。多情景模拟中,粮食生产激励政策对提高农户粮食作物决策值具有显著正向影响,非粮化市场饱和能有效抑制经济作物型非粮化,吸引劳动力回流可有效缓解撂荒现象。最后,提出针对性的农业非粮化格局优化策略,为促进农村可持续发展提供参考。 展开更多
关键词 梯田非粮化 农户 行为决策 多智能体系统(MAS) 陇中陇东地区
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