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High Standard Capital Farmland Construction Based on Grain Security 被引量:1
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作者 Zhi ZHANG Zhongxiang YU 《Asian Agricultural Research》 2016年第5期40-45,共6页
In the context that global grain security is still in very severe situation,the grain security situation in China is not optimistic as well. The " Red Line of Farmland Area" cannot completely solve the grain... In the context that global grain security is still in very severe situation,the grain security situation in China is not optimistic as well. The " Red Line of Farmland Area" cannot completely solve the grain security problems in China. We still need to seek new breakthroughs in the quality and yield of farmland. The construction of high standard capital farmland is the important premise to guarantee national grain security. On this basis,this paper has summarized the difficulties we are facing in the construction of high standard capital farmland,and has proposed the methods and measures to construct high standard capital farmland and lay a solid foundation for grain security in China. 展开更多
关键词 GRAIN SECURITY FARMLAND quality high standard CAPITAL FARMLAND
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Zoning Approach of Key Construction Areas of High Standard Capital Farmland in Guangdong Province 被引量:1
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作者 SHEN Ming SU Shao-qing +3 位作者 HU Yue-ming GOU Wu-long YI Jia-chun CHEN Fei-xiang 《Asian Agricultural Research》 2012年第9期27-30,共4页
On the basis of actual situations of Guangdong Province, using Factor Analysis Approach and Quantitative Analysis Method, we built index system by four factors, namely, extent of farmland connectivity, local financial... On the basis of actual situations of Guangdong Province, using Factor Analysis Approach and Quantitative Analysis Method, we built index system by four factors, namely, extent of farmland connectivity, local financial support, grain production capacity and farmland consolidation potential. Finally, we obtained that the areas with total scores of evaluation higher than 50 points are key construction areas of high-standard capital farmland in Guangdong Province. In total, there are 40 key construction areas, including 16 in plain areas of the Pearl River Delta, 9 in coastal regions of east of Guangdong, 10 in coastal regions of west of Guangdong, and 5 in northwest mountainous regions of Guangdong. Besides, we put forward construction direction of these 4 capital farmland areas. 展开更多
关键词 high standard CAPITAL FARMLAND KEY construction ar
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Improving and Upgrading Consular Services to Better Contribute to High-Standard Opening Up
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作者 Long Zhou 《Foreign Affairs Journal》 2024年第4期1-10,102-105,共14页
I Opening up is a hallmark of contemporary China.In the report of the 20th National Congress of the Communist Party of China(CPC),promoting highstandard opening up is an important part in the section of"Accelerat... I Opening up is a hallmark of contemporary China.In the report of the 20th National Congress of the Communist Party of China(CPC),promoting highstandard opening up is an important part in the section of"Accelerating the Creation of a New Development Pattern and Pursuing High-Quality Development."The Third Plenary Session of the 2Oth CPC Central Committee stressed that we must remain committed to the basic state policy of opening up to the outside world,continue to promote reform through opening up,enhance our capacity for opening up while expanding cooperation with other countries,and develop new institutions for a higher-standard open economy. 展开更多
关键词 new development pattern basic state policy opening up contemporary china creation new development pattern th national congress high standard opening up communist party china
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Arrangement of High-standard Basic Farmland Construction Based on Village-region Cultivated Land Quality Uniformity 被引量:22
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作者 SONG Wen WU Kening +2 位作者 ZHAO Huafu ZHAO Rui LI Ting 《Chinese Geographical Science》 SCIE CSCD 2019年第2期325-340,共16页
As an important constitute of land consolidation, high-standard basic farmland construction is an important means to protect the quantity, quality and ecological environment of cultivated land. Its target not only lie... As an important constitute of land consolidation, high-standard basic farmland construction is an important means to protect the quantity, quality and ecological environment of cultivated land. Its target not only lies in the increase of cultivated land quantity, but also the improvement of cultivated land quality, agricultural production conditions and ecosystem environments. In the present study, the quality evaluation method and construction arrangement of cultivated land were explored to facilitate the process of decision-making and implementation for high-standard basic farmland construction(HSBFC) with administrative village as the unit. Taking the land comprehensive improvement project area in Quzhou County, Handan City, Hebei Province as a case study, the whole process of the study comprised of three steps: 1) establishment of the evaluation model of cultivated land quality uniformity based on regional optimum cultivated land quality, and construction of the uniformity evaluation index system from the aspects of soil fertility quality, engineering quality, spatial quality and eco-environment quality, according to the new concept of cultivated land quality; 2) calculation of cultivated land quality uniformity by grading indicators, assigning scores and weighting sums, exploring the local homogenization characteristics of regional cultivated land quality through spatial autocorrelation analysis, and analyzing the constraints and transformative potential of barrier factors; 3) arrangement of HSBFC according to the principle of concentration, continuity and priority to the easy operation. The results revealed that the value of farmland quality uniformity for the administrative villages in the study area was between 7.76 and 21.96, and there was a difference between various administrative villages. The regional spatial autocorrelation patterns included High-High(HH), Low-Low(LL), High-Low(HL) and Low-High(LH). These indicate that regional cultivated land quality has local homogenization characteristics. The most restrictive factors in the study area were the medium and low transformation difficulty indexes, including soil organic matter content, farmland shelterbelt network density, field regularity and scale of the field. In addition, there were also high transformation difficulty indicators in some areas, such as sectional configuration. The project area was divided into four partitions: major construction area, secondary construction area, general construction area, and conditional construction area. The cultivated land area of each subarea was 1538.85 ha, 1224.27 ha, 555.93 ha, and 1666.63 ha, respectively. This comprised of 30.87%, 24.56%, 11.15% and 33.42% of the total project area, respectively. The evaluation model and index system could satisfy the evaluation of farmland quality and diagnosis of obstacle factors to facilitate the subsequent construction decision. The present study provides reference for the practice of regional HSBFC, and a new feasible idea and method for related studies. 展开更多
关键词 high-standard basic FARMLAND CULTIVATED land quality UNIFORMITY barrier factor arrangement
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Assessment of High-standard Farmland Construction Effectiveness in Liaoning Province During 2011–2015 被引量:8
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作者 PU Luoman ZHANG Shuwen +2 位作者 YANG Jiuchun YAN Fengqin CHANG Liping 《Chinese Geographical Science》 SCIE CSCD 2019年第4期667-678,共12页
At present, the large-scale construction of high-standard farmland in China has improved the quality of cropland and crop production and enhanced the eco-environmental security. To obtain a comprehensive understanding... At present, the large-scale construction of high-standard farmland in China has improved the quality of cropland and crop production and enhanced the eco-environmental security. To obtain a comprehensive understanding of high-standard farmland construction in Liaoning Province of China during the 12 th five-year period(2011–2015), through on-the-spot investigations and remote sensing monitoring, this study assessed the construction effectiveness of ten typical sampling projects in Liaoning Province and then presented practical suggestions. The main conclusions were as follows. 1) The ranges of increase in productivity of the ten sampling projects in Liaoning Province all surpassed the goal of 1500 kg/ha. 2) Among all sampling project areas, the levels of productivity stability of nine sampling projects were higher than that of the surrounding farmland in a severe drought year. However, the productivity stability of the high-standard farmland construction project in Faku County, Yiniupu Town, declined by 1.04% compared with the surrounding farmland. 3) Except for the high-standard farmland construction project in Dengta City, Dengta Irrigation Region, the productivity uniformity of the other nine sampling projects increased by 3.30%–88.10%. 4) Eight of the ten sampling projects belonged to Class 1, and two projects belonged to Class 2, showing that the effectiveness of high-standard farmland construction in Liaoning Province was quite good.There were some suggestions for high-standard farmland construction in the future. All departments should strengthen cooperation and formulate corresponding protection and development strategies suitable for local conditions. Additionally, lasting management mechanisms should also be established. Using remote sensing monitoring to assess the high-standard farmland construction effectiveness during the 12 th five-year period could provide experience and decision-making support for high-standard farmland construction in the future. 展开更多
关键词 high-standard FARMLAND remote sensing monitoring PRODUCTIVITY stability PRODUCTIVITY UNIFORMITY LIAONING Province China
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High-Dimensional Spatial Standardization Algorithm for Diffusion Tensor Image Registration 被引量:1
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作者 Tao Guo Quan Wang +1 位作者 Yi Wang Kun Xie 《Journal of Beijing Institute of Technology》 EI CAS 2018年第4期604-616,共13页
Three high dimensional spatial standardization algorithms are used for diffusion tensor image(DTI)registration,and seven kinds of methods are used to evaluate their performances.Firstly,the template used in this paper... Three high dimensional spatial standardization algorithms are used for diffusion tensor image(DTI)registration,and seven kinds of methods are used to evaluate their performances.Firstly,the template used in this paper was obtained by spatial transformation of 16 subjects by means of tensor-based standardization.Then,high dimensional standardization algorithms for diffusion tensor images,including fractional anisotropy(FA)based diffeomorphic registration algorithm,FA based elastic registration algorithm and tensor-based registration algorithm,were performed.Finally,7 kinds of evaluation methods,including normalized standard deviation,dyadic coherence,diffusion cross-correlation,overlap of eigenvalue-eigenvector pairs,Euclidean distance of diffusion tensor,and Euclidean distance of the deviatoric tensor and deviatoric of tensors,were used to qualitatively compare and summarize the above standardization algorithms.Experimental results revealed that the high-dimensional tensor-based standardization algorithms perform well and can maintain the consistency of anatomical structures. 展开更多
关键词 diffusion tensor imaging high dimensional spatial standardization REGISTRATION TEMPLATE evaluation
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China's High Performance Computer Standard Commission Established
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《China Standardization》 2007年第4期40-,共1页
  China's High Performance Computer Standard Commission was established on March 28, 2007, under the guidance of the Science and Technology Bureau of the Ministry of Information Industry. It will prepare relevan...   China's High Performance Computer Standard Commission was established on March 28, 2007, under the guidance of the Science and Technology Bureau of the Ministry of Information Industry. It will prepare relevant professional standards on high performance computers to break through the monopoly in the field by foreign manufacturers and vendors.…… 展开更多
关键词 high China’s high Performance Computer standard Commission Established
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2025 Qingdao Forum on International Standardization held successfully
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作者 Jin Jili 《China Standardization》 2025年第5期36-39,共4页
The 2025 Qingdao Forum on International Standardization was held at the Qingdao International Conference Center on July 9.With the theme of“high-level standards leading high-quality development”,the forum was hosted... The 2025 Qingdao Forum on International Standardization was held at the Qingdao International Conference Center on July 9.With the theme of“high-level standards leading high-quality development”,the forum was hosted by Qingdao Municipal People’s Government and organized by Qingdao Administration for Market Regulation. 展开更多
关键词 high quality development high level standards international standardization
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高标准农田气象服务需求及服务能力提升途径
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作者 杨霏云 查菲娜 +3 位作者 董宛麟 郭康军 李梦夏 伍露 《中国农业气象》 2026年第1期1-6,共6页
农业气象服务是中国气象事业中规模最大、体系最完善的专业气象服务,在农业生产气象保障中发挥了重要作用。随着中国农业生产向规模化种植转型,高标准农田建设的持续推进对农业气象服务提出了新需求。本研究通过实地调查、梳理现有服务... 农业气象服务是中国气象事业中规模最大、体系最完善的专业气象服务,在农业生产气象保障中发挥了重要作用。随着中国农业生产向规模化种植转型,高标准农田建设的持续推进对农业气象服务提出了新需求。本研究通过实地调查、梳理现有服务产品,分析高标准农田气象保障服务需求要点,结合当前供给端服务现状分析,提出高标准农田气象保障能力提升的路径,以期为提升高标准农田建设气象保障服务的针对性和有效性提供参考。结果表明:部分省(区、市)气象部门围绕高标准农田气象保障能力建设,布设了农田小气候、自动土壤水分等多个种类的自动化气象观测设备,在高标准农田地块上初步建成了农业气象自动观测站网,形成了一批针对高标准农田的气象服务产品。但当前高标准农田气象保障服务存在气象观测站布局缺乏系统谋划,数据采集标准不统一、服务产品未满足精细化需求、数据管理机制不完善等问题。基于此,建议加强顶层设计、提升数据价值、聚焦技术创新和开展社会化服务,以期提升高标准农田气象保障服务能力。 展开更多
关键词 高标准农田 气象服务 社会化服务 数据价值
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高标准农田建设政策对农业碳排放的影响
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作者 周利平 月莉婷 《中国生态农业学报(中英文)》 北大核心 2026年第1期33-44,共12页
高标准农田建设是农业绿色转型的重要抓手,是推动农业高质量发展的有力支撑。本文基于2006—2020年中国30个省(自治区、直辖市,未包含西藏、香港地区、澳门地区及台湾地区)的面板数据,采用连续型双重差分法,系统评估高标准农田建设政策... 高标准农田建设是农业绿色转型的重要抓手,是推动农业高质量发展的有力支撑。本文基于2006—2020年中国30个省(自治区、直辖市,未包含西藏、香港地区、澳门地区及台湾地区)的面板数据,采用连续型双重差分法,系统评估高标准农田建设政策对农业碳排放的影响及其作用路径。研究发现:1)高标准农田建设政策对抑制农业碳排放具有显著的积极作用,且该结论在多种稳健性检验下依然成立。2)异质性分析发现,高标准农田建设政策在不同土地质量以及粮食主产区的减排效果上存在显著差异。3)机制检验结果表明,高标准农田建设政策通过降低农业能源消耗强度和提升土地生产率对农业碳排放产生抑制作用。据此,提出应进一步优化各级政府财政支出结构,切实有效地推进高标准农田建设;推广节能农业机械设备、改良土壤、优化种植结构;秉持因地制宜的原则,采取多元化手段精准高效地推广并执行高标准农田建设的政策措施。 展开更多
关键词 高标准农田建设政策 农业碳排放 农业能源消耗强度 土地生产率 连续型双重差分法
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中国企业家精神的生成逻辑与时代使命
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作者 周文 杨正源 《云南民族大学学报(哲学社会科学版)》 北大核心 2026年第1期99-108,共10页
诞生于西方市场经济环境的企业家精神理论,因其原子式个体与“守夜人”政府的理论预设,难以系统性解释中国在独特制度情境下企业家群体大规模涌现的生成机理。中国企业家精神是一种发展型企业家精神,其生成逻辑根植于高水平社会主义市... 诞生于西方市场经济环境的企业家精神理论,因其原子式个体与“守夜人”政府的理论预设,难以系统性解释中国在独特制度情境下企业家群体大规模涌现的生成机理。中国企业家精神是一种发展型企业家精神,其生成逻辑根植于高水平社会主义市场经济体制下有为政府与有效市场的协同演进,并系统性地塑造了企业家兼具市场创新者与国家战略协同者的双重角色。新时代的企业家精神,以产业报国的爱国情怀为价值内核,以推动科技创新与产业创新融合发展为核心使命,以诚信为本的契约精神为立身之本,以共享与可持续发展为社会责任,以胸怀天下的国际视野为全球格局。因此,应从三个层面系统性推进弘扬企业家精神:一是完善产权保护与公平竞争的基础性制度框架;二是构建适配创新周期的金融供给机制;三是进一步构建亲清政商关系,从而为企业家履行其时代使命提供坚实的制度保障。 展开更多
关键词 企业家精神 中国特色现代企业制度 高水平社会主义市场经济体制 亲清政商关系
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基于AHP-模糊综合模型的高标准农田气象保障工程质量评价
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作者 崔童 姬兴杰 +1 位作者 房勇 纪潇潇 《中国农业气象》 2026年第1期20-33,共14页
以高标准农田气象保障工程质量为研究对象,利用德尔菲法识别工程质量影响因素,建立工程质量综合评价指标体系,应用层次分析法求解各指标权重,基于模糊综合评价法构建适用于高标准农田气象保障工程质量的定量化评价模型,评估工程质量的... 以高标准农田气象保障工程质量为研究对象,利用德尔菲法识别工程质量影响因素,建立工程质量综合评价指标体系,应用层次分析法求解各指标权重,基于模糊综合评价法构建适用于高标准农田气象保障工程质量的定量化评价模型,评估工程质量的综合及单项指标等级、得分,指出工程建设质量的优势和短板,为工程质量评价、规划和升级提供参考。结果表明:高标准农田气象保障工程质量评价指标涵盖观测站网工程建设质量、预报预警系统建设质量、信息发布系统建设质量、防灾减灾工程建设质量、气象保障效益评估5个一级指标、8个二级指标和25个三级指标。5个一级指标的权重排序由高到低依次为观测站网(0.261)>预报预警(0.251)>防灾减灾(0.228)>信息发布(0.154)>效益评估(0.106),其中,观测站网、预报预警和防灾减灾3项一级指标的权重占比74%,是工程质量评价的关键性指标。信息发布和效益评估2项一级指标权重虽只占26%,但在为农气象服务链条中起前后衔接重要作用;二级指标中,同属1个一级指标下的3对二级指标两两间权重相差较小;三级指标中,灌溉与排水工程质量、灾情预报预警准确率、观测数据及时性指标是权重最高的前3项。以河南省郸城县的某高标准农田气象保障工程为案例,工程质量综合评分为86.3分,属良好等级。其中,5个一级指标均为良好,但各三级指标的评价结果存在差异,在观测站网工程建设、气象信息发布系统、防灾减灾基础设施和能力建设方面效用较好,但预报预警准确率和为农服务满意度等方面存在薄弱点。案例应用结果验证了综合评价模型的有效性和适用性,也为工程质量评价和管理提供了依据。 展开更多
关键词 高标准农田 气象保障工程 模糊综合评价法 工程质量 评价指标
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高标准农田建设对农业气象灾害防御的影响与机制
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作者 田红宇 曹云楚 孟娜娜 《中国农业气象》 2026年第1期34-47,共14页
利用自然社会交互耦合视角,构建“气象环境−耕地质量−主体响应−防灾减损”的理论框架,基于2004−2022年中国省级层面高标准农田建设及农业气象灾害数据,运用连续型双重差分模型,系统分析农业气象灾害中高标准农田建设的防灾减损效应及机... 利用自然社会交互耦合视角,构建“气象环境−耕地质量−主体响应−防灾减损”的理论框架,基于2004−2022年中国省级层面高标准农田建设及农业气象灾害数据,运用连续型双重差分模型,系统分析农业气象灾害中高标准农田建设的防灾减损效应及机制。结果表明:(1)高标准农田建设显著且持续提升了农业气象灾害防御能力,对农业气象灾害冲击具有明显的防灾减损效应。新增高标准农田建设面积大的(≥5.3万hm^(2))实验组,其农业气象灾害成灾率显著下降了12.7个百分点,因灾粮食损失降低了16.5%。经平行趋势和稳健性检验后结果可信。(2)在灾害类型、建后管护水平和区域农业功能定位三个维度上高标准农田建设的防灾减损效应均可发挥积极的作用,其中对农业抵御旱灾的能力最为显著,在高标准农田管护水平高的区域防灾减损效应更为突出,在粮食主产省份的防灾减损效果较主销区更为明显。(3)带动农业保险和灾害监测预警能力提升,促进农业社会化服务和设施农业发展,是高标准农田建设助力农业防灾减损的重要途径。为此,在加快推进新一轮高标准农田建设时,坚持差异化阶段推进原则,探索“建管用养”一体化发展的长效机制,引导高标准农田的使用方式向现代化集约化转型,可为农业强国建设提供根本支撑。 展开更多
关键词 高标准农田建设 农业气象灾害 防灾减损效应
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教育大模型数据治理与共享标准框架构建研究
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作者 吴永和 陈圆圆 +1 位作者 吴慧娜 马晓玲 《开放教育研究》 北大核心 2026年第1期54-66,共13页
智能范式背景下,教育数据呈现来源异构、授权不清、依赖情境、高敏感性等特征,带来协作治理、隐私保护、跨域共享等挑战。本研究以高质量教育数据为核心,提出“安全—质量—语境”的内涵特性,明确教育数据规范管理与高效利用的核心目标... 智能范式背景下,教育数据呈现来源异构、授权不清、依赖情境、高敏感性等特征,带来协作治理、隐私保护、跨域共享等挑战。本研究以高质量教育数据为核心,提出“安全—质量—语境”的内涵特性,明确教育数据规范管理与高效利用的核心目标与价值导向;构建了教育大模型数据治理和共享标准框架,并从释放数据价值、规范生成数据、强化知识支撑和构建协同机制四方面展望其未来发展。这一框架有助于为教育大模型的预训练和测评提供数据支撑,促进其安全、高效、可信地应用。 展开更多
关键词 教育大模型 数据治理 数据共享 高质量教育数据 标准框架
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Challenges of the Performance Standards of the International Finance Corporation in Financing the African Integrated High-Speed Railway Network and the Way Forward: The Case of Standard Gauge Railway in Tanzania
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作者 Emmanuele Elifadhili Mchome Uwezo Wilbard Nzoya 《Journal of Transportation Technologies》 2023年第4期772-788,共17页
Financing of the African Integrated High-Speed Railway Network (AIHSRN) through Standard Gauge Railway (SGR) Projects is very expensive. As a result, most of the African countries seek financial supports from the Inte... Financing of the African Integrated High-Speed Railway Network (AIHSRN) through Standard Gauge Railway (SGR) Projects is very expensive. As a result, most of the African countries seek financial supports from the International Financial Institutions (IFIs). However, conditions provided by the IFIs through the Performance Standards (PS) of the International Financial Corporation (IFC) increase cost of the projects and thus, it becomes a burden to most of the African countries. This study aimed to explore the causes of IFC-PS through the SGR Projects that escalate costs and how to address them. The Tanzania SGR Lot 1 Project that covered 205 km from Dar es Salaam to Morogoro was selected as a case study. The methods used for data collection involved literature review, focus group discussions and interviews. The results and findings show a gap between the IFC-PS and the National Laws and Regulations that escalates costs of the projects if funds from the IFIs were to be secured. To bridge the gap, it is recommended that the African countries should engage into negotiations with the IFIs to agree to waive IFC-PS conditions that escalate costs provided they are adequately covered in the national laws and regulations;engagement of locally established national and regional financial institutions;and the responsible government institutions in the African countries should sit together for assessment and review of the IFC-PS against the national laws and regulations. 展开更多
关键词 African Integrated high-Speed Railway Network International Financial Institutions standard Gauge Railway Performance standards
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坚持深化核心素养理念——《普通高中地理课程标准日常修订版(2017年版2025年修订)》解读
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作者 段玉山 丁荣 《天津师范大学学报(基础教育版)》 北大核心 2026年第1期23-29,共7页
为回应新时代教育发展需求和课程实施中的现实问题,教育部颁布了《普通高中地理课程标准日常修订版(2017年版2025年修订)》。本次课标修订体现了“守正”与“创新”的辩证统一:在坚守习近平新时代中国特色社会主义思想指导和立德树人根... 为回应新时代教育发展需求和课程实施中的现实问题,教育部颁布了《普通高中地理课程标准日常修订版(2017年版2025年修订)》。本次课标修订体现了“守正”与“创新”的辩证统一:在坚守习近平新时代中国特色社会主义思想指导和立德树人根本任务的基础上,直面时代课题与实践挑战,对地理课程标准进行系统性完善与发展。本次修订主要体现在三个方面:一是理念深化,明确将习近平新时代中国特色社会主义思想写入课程性质,构建“四个坚持”的课程理念,优化核心素养内涵表述,系统融入党的二十大和二十届三中全会精神;二是结构优化,重新梳理课程设计依据,明确课程模块功能定位,强化课程内容时代性,重构学业质量标准,创新性地以“综合性、区域性、实践性”为底层逻辑,将原有四级水平调整为三级水平;三是实践强化,优化问题式教学建议,强化地理实践力培育,并首次在课程标准中明确人工智能在教学中的应用,优化表现性评价,重构学业水平考试命题建议。本次课标修订在继承的基础上实现了发展:强化国家意志与时代精神的课程表达;凸显科学教育与人文教育的双重担当;构建学业质量与考试评价的整体协调机制。 展开更多
关键词 高中地理 地理课程标准 学业质量 核心素养 课标解读
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中国高标准农田建设政策对口粮自给率的影响
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作者 李子烨 马琼 胡惟肖 《农业资源与环境学报》 北大核心 2026年第1期28-39,共12页
为探究高标准农田建设政策对口粮自给率的影响,本研究利用2003—2022年间26个省份的均衡面板数据,通过构建连续型双重差分模型,深入剖析高标准农田建设政策对口粮自给率产生的具体影响,并进一步探讨其潜在的作用机制。结果表明:高标准... 为探究高标准农田建设政策对口粮自给率的影响,本研究利用2003—2022年间26个省份的均衡面板数据,通过构建连续型双重差分模型,深入剖析高标准农田建设政策对口粮自给率产生的具体影响,并进一步探讨其潜在的作用机制。结果表明:高标准农田建设政策对于提升口粮自给率具有显著的正面效应,同时,该结论通过了稳健性检验。异质性分析表明,政策实施效果在粮食主产区更明显,在东、中、西部的效果依次下降。作用机制检验表明,高标准农田建设政策通过促进土地流转、农业机械化来提升口粮自给率。研究表明,高标准农田建设政策能促进口粮自给率的提高,这种促进作用存在滞后性和持续性,同时与粮食生产功能区定位及地理区位息息相关。研究建议贯彻执行新一轮高标准农田建设,对于不同地区因地制宜进行改造;重视土地流转及宜机化改造,强化高标准农田建后管护工作,确保口粮绝对安全,强化粮食安全保障。 展开更多
关键词 高标准农田建设 口粮自给率 土地流转 农业机械化 连续型双重差分
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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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河南省高标准农田参考作物蒸散量影响因素及其模拟
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作者 褚荣浩 李萌 +3 位作者 沙修竹 成林 姬兴杰 陈曦 《中国农业气象》 2026年第1期83-96,共14页
针对小气候站数据质量等问题给参考作物蒸散量(ET_(0))估算带来的挑战,选取河南省高标准农田2020−2023年16个有完整数据记录的农田小气候站和13个临近国家气象站点逐日气象观测数据,采用13种典型ET_(0)估算经验模型和8种机器学习模型,以... 针对小气候站数据质量等问题给参考作物蒸散量(ET_(0))估算带来的挑战,选取河南省高标准农田2020−2023年16个有完整数据记录的农田小气候站和13个临近国家气象站点逐日气象观测数据,采用13种典型ET_(0)估算经验模型和8种机器学习模型,以Penman−Monteith(PM)模型为基准,评估不同模型的准确性,并在最优模型的基础上提供15种ET_(0)组合方案,以期提供一个准确、合适、简单的替代模型估算ET_(0),为高标准农田农业水资源管理提供科学指导。结果表明:除风速(WS)外,小气候站与国家站逐日观测的平均气温(T_(ave))、最高气温(T_(max))、最低气温(T_(min))、平均空气相对湿度(RH)、饱和水汽压差(VPD)和净辐射(Rn)拟合度较高,R^(2)均高于0.654(P<0.05),基于两套数据计算的ET_(0)相关关系也较好,R^(2)为0.880,RMSE为0.59mm。13种经验模型中,综合考虑温度、辐射、相对湿度和风速的Valiantzas3(Val3)模型效果最佳(R^(2)=0.933,RMSE=0.461mm),其次是考虑辐射和温度因子的Jensen−Haise(JH)模型(R^(2)=0.916,RMSE=0.774mm)。基于温度的Hargreaves−Samani(HS)模型的总体精度较高(R^(2)=0.817,RMSE=0.713mm);而基于质量传输的Penman(Pen)、WMO和Trabert(Tra)模型的模拟精度较低,不建议作为ET_(0)评估的选择方案。8种机器学习模型中,多层感知机(MLP)模型模拟精度最优(R^(2)=0.998,RMSE=0.059mm),各输入参数重要性排序为Rn>VPD>WS>T_(max)>T_(ave)>T_(min)>RH。基于MLP模型的15种模型输入参数组合方案中,相同输入参数条件下,机器学习模型的模拟精度总体优于经验模型,综合考虑Rn+T_(ave)+RH+WS的组合模型表现最优。 展开更多
关键词 高标准农田 参考作物蒸散 经验模型 机器学习模型 蒸散模拟
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基于大田试验的冬小麦气象服务效益定量评估初探
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作者 郭康军 姬兴杰 董宛麟 《中国农业气象》 2026年第1期7-19,F0002,共14页
2023年10月在河南省新乡市高标准农田设置完全响应区、部分响应区和不响应区,并在部分响应区随机布设仅不开展赤霉病防控和仅不开展干热风防控两种处理,共5个试验处理。试验期间按照2期河南省农业气象灾害预警信息(干热风、赤霉病)和2... 2023年10月在河南省新乡市高标准农田设置完全响应区、部分响应区和不响应区,并在部分响应区随机布设仅不开展赤霉病防控和仅不开展干热风防控两种处理,共5个试验处理。试验期间按照2期河南省农业气象灾害预警信息(干热风、赤霉病)和2期河南省农业气象服务周报建议,于试验点开展2次灌溉(返青期、拔节期)、赤霉病防控(抽穗期)和干热风防控(灌浆期)处理,并结合其他调查及观测结果,定量分析农业气象服务信息不同响应处理对冬小麦主要生长要素及经济效益的影响。结果表明:(1)及时响应(1~14d)冬小麦赤霉病和干热风灾害预警信息,并进行相关防控,可有效减轻危害,部分响应区赤霉病防控地块冬小麦赤霉病病穗率降低1.50个百分点,部分响应区干热风防控地块千粒重提高1.42g,灌浆速率提高0.12g·d^(−1)。(2)冬小麦抽穗期和灌浆期不同响应处理下,主要生长要素差异显著。完全响应处理下抽穗期平均穗、茎和叶干重分别为2.73g、6.57g和2.74g,整体高于部分响应处理;灌浆期平均穗、叶干重和穗粒数分别为21.34g、2.15g和41.93个,整体呈完全响应处理>部分响应处理>不响应处理的趋势。(3)对农业气象服务信息及时响应,可显著增产增收。完全响应处理较部分响应处理每公顷冬小麦可增产666.67kg,增收1690.00元,较不响应处理每公顷增产2310.81kg,增收4435.95元;部分响应处理较不响应处理每公顷可增产1644.14kg,增收2745.95.元。通过对农业气象服务信息不同响应处理产生的效益进行定量评估,对提升冬小麦单产具有重要科技支撑和生产指导意义。 展开更多
关键词 河南 冬小麦 气象服务效益 高标准农田
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