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Urban construction land demand prediction and spatial pattern simulation under carbon peak and neutrality goals:A case study of Guangzhou,China 被引量:6
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作者 HU Xintao LI Zhihui +1 位作者 CAI Yumei WU Feng 《Journal of Geographical Sciences》 SCIE CSCD 2022年第11期2251-2270,共20页
Urban construction land has relatively high human activity and high carbon emissions.Research on urban construction land prediction under carbon peak and neutrality goals(hereafter“dual carbon”goals)is important for... Urban construction land has relatively high human activity and high carbon emissions.Research on urban construction land prediction under carbon peak and neutrality goals(hereafter“dual carbon”goals)is important for territorial spatial planning.This study analyzed quantitative relationships between carbon emissions and urban construction land,and then modified the construction land demand prediction model.Thereafter,an integrated model for urban construction land demand prediction and spatial pattern simulation under“dual carbon”goals was developed,where urban construction land suitability was modified based on carbon source and sink capacity of different land-use types.Using Guangzhou as a case study,the integrated model was validated and applied to simulate the spatiotemporal dynamics of its urban construction land during 2030–2060 under baseline development and“dual carbon”goals scenarios.The simulation results showed that Guangzhou’s urban construction land expanded rapidly until 2030,with the spatial pattern not showing an intensive development trend.Guangzhou’s urban construction land expansion slowed during 2030–2060,with an average annual growth rate of 0.2%,and a centralized spatial pattern trend.Under the“dual carbon”goal scenario,Guangzhou’s urban construction land evolved into a polycentric development pattern in 2030.Compared with the baseline development scenario,urban construction land expansion in Guangzhou during 2030–2060 is slower,with an average annual growth rate of only 0.1%,and the polycentric development pattern of urban construction land was more prominent.Furthermore,land maintenance and growth,that is,a carbon sink,is more obvious under the“dual carbon”goals scenario,with the forest land area nearly 10.6%higher than that under the baseline development scenario.The study of urban construction land demand prediction and spatial pattern simulation under“dual carbon”goals provides a scientific decision-making support tool for territorial spatial planning,aiding in quantifying territorial spatial planning. 展开更多
关键词 carbon peak and neutrality goals urban construction land demand prediction spatial pattern simulation GUANGZHOU
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Factors That Affect Consumption Patterns and Market Demands for Honey in the Kingdom of Saudi Arabia
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作者 Sobhy Ismaiel Safar Al Kahtani +2 位作者 Nuru Adgaba Ahmed A. Al-Ghamdi Abdu Zulail 《Food and Nutrition Sciences》 2014年第17期1725-1737,共13页
Despite the significant annual consumption of honey in Saudi Arabia, information gaps remain with regard to the marketing and market structure of honey along the value chain. This study analyzed the major factors that... Despite the significant annual consumption of honey in Saudi Arabia, information gaps remain with regard to the marketing and market structure of honey along the value chain. This study analyzed the major factors that influenced the consumption, expenditure patterns, and demand of honey in Saudi Arabia. This study forecasted the near-future expected market demands for honey in Saudi Arabia by collecting and analyzing the primary data using questionnaires. A total of 331 respondents from representative regions and large cities were randomly selected and interviewed. The data were analyzed using qualitative and quantitative methods as well as appropriate econometric models. Respondents characterized honey quality using organoleptic words, and these characterizations varied based on the relative significance of perception parameters. Taste, aroma, physical state, and color had aggregated average scores of 4.58, 4.44, 3.54, and 3.28, respectively. In addition to the above parameters, honey source, brand name, and confidence in the producers influenced its perceived quality. The major outlets for honey in Saudi Arabia included producers, specialized honey stores, and auction markets in major cities during the harvesting seasons. Medication, food, and sweetening were the major motivations for buying honey in the Saudi market, with aggregate scores of 4.52, 3.71, and 1.52, respectively. Significant honey price variations were observed within and among different honeys and packaging volumes;this finding might be due to factors such as botanical and geographical origins, package volume size economics (i.e., bulk purchases), honey variety blending, brand names, and producer policies. The average price of locally produced honey was approximately $73 per kg, which is 10 times more than the average price of honey in the US and the EU. The estimated consumption/income elasticity was 0.27. These results suggest that honey is a basic commodity in Saudi Arabia. Based on econometric model forecasts, the Saudi market demand for honey is expected to reach approximately 29,784 tons in 2025. 展开更多
关键词 HONEY Consumption patterns demand Forecasting HONEY Quality ELASTICITY MARKETING DEFICIENCIES
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Influencing Factors of Expanding Domestic Demand under Double Circulation New Pattern
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作者 WANGJingjing 《外文科技期刊数据库(文摘版)经济管理》 2022年第2期081-084,共4页
The new development pattern with the major domestic cycle as the main body and the double domestic and international cycles promoting each other is another important strategic measure proposed by the CPC Central Commi... The new development pattern with the major domestic cycle as the main body and the double domestic and international cycles promoting each other is another important strategic measure proposed by the CPC Central Committee to deal with the current domestic economic developing situation. And the construction of the double cycle pattern should be based on the strategic basis of domestic demand, how to appropriately expand the total demand, especially the expansion of domestic demand is the problem in front of the current Chinese market. This paper tries to analyze the factors affecting the expansion of domestic demand. Hope that through the relevant exposition of this paper, we can find a way not to produce economic bubble, inflation, and can find an effective way to achieve the rapid and stable development of the current economy. 展开更多
关键词 domestic demand dual cycle new pattern
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Unveiling water purification dynamics:A supply-flow-demand perspective from the Xiangjiang River Basin
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作者 DENG Chuxiong HUA Ye +1 位作者 LIU Yaojun ZHANG Guangjie 《Journal of Geographical Sciences》 2025年第12期2664-2684,共21页
The equilibrium between the supply and demand of water purification services is essential for safeguarding watershed ecosystems and supporting sustainable socio-economic growth.While current research mainly emphasizes... The equilibrium between the supply and demand of water purification services is essential for safeguarding watershed ecosystems and supporting sustainable socio-economic growth.While current research mainly emphasizes the static analysis of this balance,dynamic investigations into service flow characteristics remain scarce.This study focuses on the Xiangjiang River Basin in southern China,utilizing the InVEST model,differential equations governing supply and demand,and social network analysis to investigate the spatio-temporal patterns of water purification service supply and demand.The results reveal that between 2000 and 2020,the supply of water purification services showed a slight upward trend,while demand exhibited a fluctuating downward tendency,and the supply-demand surplus fluctuated.On an annual basis,the supply generally met the demand,but significant spatial variation in supply-demand balance was observed,with high-risk zones concentrated in the central Hengshao arid corridor and the northern Changzhutan metropolitan area.In the water purification service network,surplus nodes increased,while deficit nodes decreased over time.Network density improved from 98.96%in 2000 to 100%in 2020.The flow of surplus services from upstream regions alleviated supply-demand imbalances downstream,notably in the Hengyang-Shaoyang(Hengshao)arid corridor and the Changsha-Zhuzhou-Xiangtan(Changzhutan)metropolitan area.However,during drought years,diminished water volume intensified supply-demand pressures in these regions.This research framework,which incorporates the dynamic effects of service flow,broadens the scope of water purification service studies and provides a solid foundation for integrated water resource and environmental management. 展开更多
关键词 water purification service supply and demand pattern water purification service flow network analysis Xiangjiang River Basin
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生态系统服务供需匹配视角下陕甘宁地区生态安全格局
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作者 叶樊妮 方信卓 龚碧凯 《干旱区研究》 北大核心 2026年第1期188-199,共12页
生态安全格局是增进人类福祉与维持区域可持续发展的重要基础。本研究以生态敏感区与生态过渡带的陕甘宁地区为研究对象,通过构建“供需匹配-格局分析-优化重组”的研究框架,运用InVEST模型、供需综合参数评估生态系统服务供需关系动态... 生态安全格局是增进人类福祉与维持区域可持续发展的重要基础。本研究以生态敏感区与生态过渡带的陕甘宁地区为研究对象,通过构建“供需匹配-格局分析-优化重组”的研究框架,运用InVEST模型、供需综合参数评估生态系统服务供需关系动态变化情况,并结合电路理论分析生态安全格局特征进而提出优化重组策略。结果表明:(1)陕甘宁地区生态系统服务供需关系时空分异显著,总体供过于求,呈现出“南供北需、局地失衡”的特征。(2)2000—2020年生态源地遵循“由北至南”集中连片分布的格局;生态廊道与生态夹点均呈现“数量先减后增、长度面积持续收缩”的特征;生态障碍点数量增加49个,面积增加588.66km^(2)。(3)以陕甘宁地区生态系统服务供需关系及生态安全格局时空特征为基础,提出“一轴一点”“两屏多区”的生态安全格局构建与优化策略,为制定区域生态保护规划及未来可持续发展提供科学依据及方法借鉴。 展开更多
关键词 生态系统服务 陕甘宁地区 供需匹配 电路理论 生态安全格局
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“黑、红”事件下城市居民出行韧性——基于海口市网约车大数据研究
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作者 段怡嫣 翟国方 胡洋 《灾害学》 北大核心 2026年第1期124-132,共9页
为揭示灾害与节假日对城市居民出行需求分布的差异化影响,该文基于海口市市域网约车出行OD大数据,运用网络分析、空间自相关分析方法,研究两次台风及小长假前后的出行需求时空分布特征。结果表明:从宏观出行网络结构到微观地理空间集聚... 为揭示灾害与节假日对城市居民出行需求分布的差异化影响,该文基于海口市市域网约车出行OD大数据,运用网络分析、空间自相关分析方法,研究两次台风及小长假前后的出行需求时空分布特征。结果表明:从宏观出行网络结构到微观地理空间集聚层面,出行需求的时序性波动均符合“过程韧性”特征。然而,不同事件下出行网络核心街道、上车及下车需求均衡性及其热点存在显著差异。由此,提出“黑、红”事件概念,用以描述两类事件下差异化的韧性时空格局,为城市空间治理及韧性提升的思路提供参考。 展开更多
关键词 出行需求 时空格局 韧性 台风 小长假 网约车
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“供给-流动-需求”视角下雨洪安全格局构建与优化:以湖北省通城县为例
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作者 李锦 廖文秀 +1 位作者 周燕 祁梦园 《华中农业大学学报》 北大核心 2026年第1期117-129,共13页
为缓解城市洪涝灾害、促进雨洪调节服务供需匹配,推动城乡生态空间高质量发展,引入生态系统服务流理论,构建耦合雨洪调节服务供需作用与服务流动机制的雨洪安全格局。以湖北省通城县为例,采用SCSCN模型与洪水风险指数分别量化雨洪调节... 为缓解城市洪涝灾害、促进雨洪调节服务供需匹配,推动城乡生态空间高质量发展,引入生态系统服务流理论,构建耦合雨洪调节服务供需作用与服务流动机制的雨洪安全格局。以湖北省通城县为例,采用SCSCN模型与洪水风险指数分别量化雨洪调节服务的供给与需求;通过冷热点分析识别生态供需源地;基于水文分析和电路理论构建雨洪调节服务的流动路径,划定蓝线廊道、绿线廊道与供需廊道,并识别关键节点。结果表明:通城县雨洪调节服务供需呈现“西南-东北盈余、中心赤字”的显著错配格局,且中心城区供需失衡程度尤为突出,共识别出供给源地276.15 km^(2),需求源地189.87 km^(2),各类廊道391.71 km,关键生态节点100处。据此提出“三区三带”优化方案,通过强化服务流动路径连通与关键节点保护等措施实现格局优化;并从供给、需求、服务流空间3个维度系统提出调控策略。 展开更多
关键词 雨洪安全格局 生态系统服务流 供需匹配 雨洪调节服务 生态网络
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河北省饲料粮供需时空演变特征与驱动机制研究
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作者 宋帅 吴希妍 +3 位作者 李文萱 郅梦雪 牛默涵 张艳新 《现代农业研究》 2026年第1期81-88,共8页
以2010—2022年河北省饲料粮供需为研究对象,综合运用核密度估计、空间自相关分析与空间杜宾模型,系统揭示其时序演化与空间布局特征,并识别关键驱动机制。研究发现:饲料粮供需演变呈明显非对称性,供给侧总体平稳且存在区域收敛趋势,而... 以2010—2022年河北省饲料粮供需为研究对象,综合运用核密度估计、空间自相关分析与空间杜宾模型,系统揭示其时序演化与空间布局特征,并识别关键驱动机制。研究发现:饲料粮供需演变呈明显非对称性,供给侧总体平稳且存在区域收敛趋势,而需求侧自2016年起快速扩张并呈现显著空间极化;供需格局由“供大于求”逆转为“供不应求”,区域失衡风险加剧。农业机械总动力与播种面积是本地供给的关键驱动力,机械化还表现出强空间溢出效应,而农业用水存在区域竞争性制约。为优化饲料粮资源配置、促进畜牧业区域协同与保障粮食安全提供科学依据。 展开更多
关键词 饲料粮供需 核密度估计 空间杜宾模型 供需格局 驱动机制
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扩内需、促消费驱动共同富裕的社会协同机制研究
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作者 阳宏润 李文 《江苏大学学报(社会科学版)》 2026年第1期22-32,共11页
让扩内需、促消费成为扎实推进全体人民共同富裕的重要着力点,需要建立以分配制度改革为基础支撑、消费生态优化为客观载体、民生保障强化为风险屏障、社会结构重塑为动力源泉的“四位一体”的社会协同机制,进一步以系统性制度创新构建... 让扩内需、促消费成为扎实推进全体人民共同富裕的重要着力点,需要建立以分配制度改革为基础支撑、消费生态优化为客观载体、民生保障强化为风险屏障、社会结构重塑为动力源泉的“四位一体”的社会协同机制,进一步以系统性制度创新构建可持续的发展路径。构建三次分配协同联动的社会制度体系,有助于实现合理分配而创造消费能力;完善公平可持续的社会生态体系,有助于实现环境优化而释放消费需求;健全民生风险防控的社会保障体系,有助于夯实保障基本需求而改善消费预期;建立“橄榄型”社会的消费主体锻造体系,有助于确保主体壮大而扩容内需支撑。这一机制的核心在于协调分配体系、消费环境、民生保障与社会结构的动态平衡,为中国特色社会主义全体人民共同富裕实践提供可行的制度框架与科学的发展范式。 展开更多
关键词 消费 内需 共同富裕 中国式现代化 新发展格局
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基于生态系统服务供需关系的水网地区生态安全格局构建——以澄湖片区为例
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作者 蓝天 丁金华 《小城镇建设》 2026年第2期38-46,共9页
快速城镇化背景下,苏南水网地区生态系统服务供需失衡现象日益严重,从供需视角构建安全格局是保证区域健康发展的有效途径。本研究以具有典型水网特征的澄湖片区为对象,基于生态系统供需关系评价构建生态安全格局。结果表明:1)澄湖片区... 快速城镇化背景下,苏南水网地区生态系统服务供需失衡现象日益严重,从供需视角构建安全格局是保证区域健康发展的有效途径。本研究以具有典型水网特征的澄湖片区为对象,基于生态系统供需关系评价构建生态安全格局。结果表明:1)澄湖片区生态系统服务供需比空间分布具有明显的空间分异特征。2)基于供需关系识别生态源地36个,是生态系统服务供给高值区,需求源地22个,主要分布在城镇建成区;提取生态廊道80条,呈网状分布,21条供需廊道有效连接生态源地和需求源地;识别生态节点21处、供需节点32处。3)构建“三区七带两组团”的生态安全格局,“三区”是基于生态源地分布划定的供给核心区,“七带”是依据廊道确定的供给保护带和供需调节带,“两组团”是参照需求源地划定的高需求组团。研究对加强水网地区生态安全保护、促进生态系统服务供需平衡提供参考。 展开更多
关键词 生态系统服务供需 生态安全格局 InVEST模型 电路理论 澄湖片区
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The Spatiotemporal Pattern Characteristics and Driving Mechanism of Recreational Services Supply and Demand in the Yangtze River Delta
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作者 YANG Liangjian ZHANG Jinhe +2 位作者 ZHU Zhiyue LIU Yaru CHEN Xiaoxin 《Journal of Resources and Ecology》 2026年第1期138-153,共16页
Recreational services(RS)play a significant role in promoting the harmonious coexistence between humans and nature and enhancing public mental health.This study systematically examined the spatiotemporal evolutionary ... Recreational services(RS)play a significant role in promoting the harmonious coexistence between humans and nature and enhancing public mental health.This study systematically examined the spatiotemporal evolutionary characteristics and coupling relationships between the supply and demand of RS in the Yangtze River Delta(YRD)region from 2010 to 2020.By integrating multi-source data—including land use,big data,and fundamental geographic information—a quantitative indicator system for the potential supply and demand of RS was constructed,and the Geo-detector method was employed to identify key driving factors.The results indicate that:(1)During the study period,spatial mismatches existed between the supply and demand of RS in the YRD,though the overall imbalance tended to decrease;(2)Both high-supply and high-demand areas exhibited significant spatial clustering,with high-supply areas primarily located in the southern part and high-demand areas concentrated in the eastern part,leading to extensive supply deficits in the eastern YRD due to spatial misalignment;and(3)The supply and demand of RS are jointly driven by natural and social factors,with tourism economic activity and urban spatial expansion being the key influencing factors.Based on these findings,we propose that regional differentiated strategies,spatial planning coordination,and data-driven governance should be adopted to enhance the supply-demand balance of RS in the YRD and promote synergistic socio-ecological development. 展开更多
关键词 recreational services spatiotemporal dynamics pattern supply and demand driving factors Yangtze River Delta
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基于生态系统服务供需的黄河中游地区生态安全格局构建
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作者 段宝玲 冯强 +1 位作者 吕萌 王晶 《水土保持研究》 北大核心 2026年第2期355-363,375,共10页
[目的]构建景观生态保育与生态系统服务亲近两种视角的生态安全格局,为保障区域生态安全与提升居民福祉提供科学参考。[方法]统筹考虑自然生态系统和人类需求,利用InVEST模型、电路理论模型等方法,从生态系统保护与人类亲近自然两个方... [目的]构建景观生态保育与生态系统服务亲近两种视角的生态安全格局,为保障区域生态安全与提升居民福祉提供科学参考。[方法]统筹考虑自然生态系统和人类需求,利用InVEST模型、电路理论模型等方法,从生态系统保护与人类亲近自然两个方面构建了黄河中游地区的生态安全格局。[结果](1)识别了48块生态源地,主要分布于生态本底优良的中部及东南部山区;识别了20块生态需求地,主要分布于研究区东南部人口密集、经济发展水平较高的城市建成区。(2)物种迁移阻力高值区集中在人类活动频繁的城市建成区,低值区主要分布在人类扰动较少的山区;居民出行阻力的低值区沿道路分布于整个研究区,高值区散布在路网覆盖度较低的西北部。(3)提取98条源间生态廊道以及65条需求生态廊道,东南部生态廊道分布密集,西北部较为稀少;识别生态夹点32844 km^(2),集中分布于生态源地与廊道的连接处、廊道与廊道的交汇处,以及生态源地附近区域;生态障碍点达1133.8 km^(2),以点状形式分散在生态廊道周围,与生态夹点位置相近但交错分布。[结论]生态源地与需求地空间分布不均衡,物种迁移阻力受人类活动影响,居民出行阻力与道路分布密切相关,形成两类生态廊道多分布于东南部的空间格局。生态修复中应重点保护现有生态源地,分级保护源间生态廊道,分类建设需求生态廊道,促进区域生态安全与居民福祉的协同保障。 展开更多
关键词 生态安全格局 生态系统服务供需 电路理论模型 黄河中游地区
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2025年国内外油气资源形势分析及展望
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作者 王彧嫣 郑志红 +3 位作者 韩志强 李文博 白羽 樊大磊 《中国矿业》 北大核心 2026年第1期30-40,共11页
在国际博弈加剧与供需矛盾叠加的背景下,保障油气资源安全的重要性日益凸显。我国油气供需缺口长期存在,外采度持续处于高位,2025年石油外采度超过70%,天然气超过40%,因此,加快国内油气勘查开采技术突破与产能提升成为维护能源安全的关... 在国际博弈加剧与供需矛盾叠加的背景下,保障油气资源安全的重要性日益凸显。我国油气供需缺口长期存在,外采度持续处于高位,2025年石油外采度超过70%,天然气超过40%,因此,加快国内油气勘查开采技术突破与产能提升成为维护能源安全的关键。本文基于“全球地缘政治-经济周期-能源转型”三维分析框架,结合对国际重大事件与能源热点的持续跟踪,依托国际货币基金组织(IMF)、国际能源署(IEA)、美国能源信息署(EIA)、欧佩克(OPEC)等权威机构的公开报告,系统分析2025年国内外油气市场格局与发展趋势,并与2020年“双碳”目标提出初期及2021年“十四五”开局阶段的核心指标进行纵向对比;同时,与美国、印度等主要油气消费国2025年数据开展横向比较。研究结果表明:全球地缘格局演变与贸易政策不确定性共同强化了经济放缓预期,叠加OPEC+增产与非OPEC国家高产量,国际石油市场供需趋于宽松,油价呈宽幅震荡下行;全球天然气市场呈现区域分化、供需趋松、波动收窄的特征,价格受地缘政治、供需关系及天气因素共同驱动。我国经济稳中有进,能源消费“稳中有增”,油气勘探在主要盆地和近海取得重要突破,产量保持“油稳气增”并创历史新高,非常规油气占比显著提升,天然气消费进一步向民生领域倾斜,但原油进口来源集中、自给率偏低等问题依然突出。展望2026年,全球石油市场将延续宽松态势,油价预计震荡下行;天然气价格呈分化走势,美国均价回升,全球市场受欧洲库存与亚洲需求制约难现大涨。国内油气产量将继续增长,原油保持稳产,天然气年产量有望再增百亿立方米,为国家能源安全和新型能源体系建设提供坚实支撑。 展开更多
关键词 油气资源 石油 天然气 油价 供需格局 勘探开发 油气资源安全
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加快构建新发展格局的理论内涵、量化评估与政策取向
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作者 解晋 汪彬 高鹤鹏 《华东经济管理》 北大核心 2026年第3期11-20,共10页
文章以习近平总书记关于加快构建新发展格局重要论述为依据,紧扣新发展格局基本内涵构建评价体系,使用全排列多边形图示法对2012—2023年中国新发展格局状况进行量化分析。研究发现,中国“新发展格局”得分上升趋势明显,东部地区最高,... 文章以习近平总书记关于加快构建新发展格局重要论述为依据,紧扣新发展格局基本内涵构建评价体系,使用全排列多边形图示法对2012—2023年中国新发展格局状况进行量化分析。研究发现,中国“新发展格局”得分上升趋势明显,东部地区最高,其次是中部、东北和西部地区,且差距扩大。“国内大循环为主体”方面,全国及各地区得分上升,东部地区最高,其次是中部、东北和西部地区,分化同样明显;“供需平衡”“科技自立自强”是主要短板。“国内国际双循环相互促进”方面,得分有波动且呈现下降趋势,东部地区最高,东北、中部、西部次之,但区域差距缩小,“双循环相互作用平衡性”是主要短板。 展开更多
关键词 新发展格局 国内大循环 双循环 供需平衡 科技自立自强
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人工智能时代消费领域的变革图景
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作者 蒋万胜 李英齐 《新经济》 2026年第1期30-41,共12页
人工智能对消费方式、消费需求及消费市场的渗透式影响正推动着消费领域变革。通过赋能智能购物平台、数字支付手段和无人零售模式升级,人工智能实现了消费方式的智能化转型,显著提升了购物体验的便捷性和个性化水平;消费者需求也随之... 人工智能对消费方式、消费需求及消费市场的渗透式影响正推动着消费领域变革。通过赋能智能购物平台、数字支付手段和无人零售模式升级,人工智能实现了消费方式的智能化转型,显著提升了购物体验的便捷性和个性化水平;消费者需求也随之呈现多元化趋势,从对智能产品、个性化定制服务的偏好到精神文化消费的进阶,反映出消费者对品质生活与情感满足的不断追求。这些变化促使消费市场重塑,主要表现为市场竞争格局演变、消费场景跨界融合和消费者主权地位提升,标志着消费生态正朝着更加智能化、协同化与用户导向的方向发展,消费领域正迈向一个以技术驱动为核心的新的时代。 展开更多
关键词 人工智能 消费方式 消费需求 消费市场
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基于马尔科夫模型自适应在线学习的电力需求预测
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作者 沈嘉怡 张飞飞 《微型电脑应用》 2026年第1期64-67,81,共5页
传统的负荷预测技术利用过去负荷需求的消费模式来获得单值负荷预测,这些技术不能评估负荷需求的内在不确定性,也不能捕捉消费模式的动态变化。针对这些问题,提出一种基于马尔科夫模型自适应在线学习的电力需求预测方案,该方案利用消费... 传统的负荷预测技术利用过去负荷需求的消费模式来获得单值负荷预测,这些技术不能评估负荷需求的内在不确定性,也不能捕捉消费模式的动态变化。针对这些问题,提出一种基于马尔科夫模型自适应在线学习的电力需求预测方案,该方案利用消费模式的动态变化评估负荷的不确定性,从而获得比离线学习更高的预测精度。文章先介绍负荷预测的基本要求,然后介绍如何用马尔科夫模型更新数据和获得概率预测能力,并在此基础上提出自适应在线学习方案,最后使用上海电网共5年的电力负荷数据对所提出的方案进行验证。测试结果表明,所提出的方案具有较高的预测精度,同时拥有较低的Pinball损失和期望校准误差。 展开更多
关键词 电力需求预测 马尔科夫模型 自适应在线学习 概率预测 消费模式变化 Pinball损失
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A preliminary study on ecological waterdemand estimation in the arid region─A case in the Qaidam Basin 被引量:3
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作者 ZHANG Xing-you SHEN Yuan-cun (Institute of Geography, Chinese Academy of Sciences, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 1999年第2期155-162,共8页
The paper emphasized the relationship between environment and water taking ecological demand water (EWD) in the Qaidam Basin─an inner basin in northwestern China, as a key issue to discuss based on landscape umpping.... The paper emphasized the relationship between environment and water taking ecological demand water (EWD) in the Qaidam Basin─an inner basin in northwestern China, as a key issue to discuss based on landscape umpping. First of all. the spatial heterogeneity of ecosystem can be reflected well by landscape pattern; secondly, landscape patterns adjust closely with environmental changes; finally, water condition is the key ecological factor for landscape pattern in the arid region.The landsat TM image of 1:100,000 on September 22, 1996 were calibrated with topographical map of the same scale, and then landscape patterns were interpreted and mapped. As a result the Qaidam Basin could be divided into 14 main types, including 67 subtypes. Concerning the characteristics of the EWD of each sub-type, the EWD in the whole basin could be estimated according to the following formula:V= (E - P ) * S = r (KEo - P ) * S Where, V is the ecological demand for Water (m3), E is the evaporation potential on terrestrial surface (m). P is the precipitation in landscape unit (m), S is the area of landscape unit (m2), Eo is the evaporation potential on water surface (m), K is the evaporation coefficient, and r is the coverage.According to the results, the ecological demand for water of desert vegetation is about 9,65×108m3, while it is about 24.48×108m3 for the lake in the inner basin. Therefore, the total EWD occupies approximately 65.7% of the total water resources in the basin. In conclusion, the quantitative method based on landscape ecological mapping is feasible, which attentively transfers the 'point'information to the 'area'. However, the preliminary results are expccted to improve by further field delta. 展开更多
关键词 the Qaidam Basin ecological water demand landscape pattern
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High Proportion Renewable Energy Supply and Demand Structure Model and Grid Impaction
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作者 Xiaoxia Wei Jie Liu +1 位作者 Tiezhong Wei Lirong Wang 《Journal of Power and Energy Engineering》 2016年第2期1-12,共12页
In considering of high proportion of renewable energy supply in 2050, the accelerating of energy consumption gross, source and environment can affect the energy system restrict affection are stronger. Add wind and sol... In considering of high proportion of renewable energy supply in 2050, the accelerating of energy consumption gross, source and environment can affect the energy system restrict affection are stronger. Add wind and solar to electricity energy with large amount of energy source exploitation. The energy source amount per person is lower. Considering the renewable energy amount and supply, primary energy storage and structure problem is standing out. Before the wide spread of renewable energy, Using the high-carbon energy in China can pollute seriously. Chinese energy supply and demand problem is research key point. This paper researches Chinese energy supply and demand pattern system and evaluation methodology, gives out the inner and outer influencing elements. And evaluate Chinese energy supply and demand pattern from energy gross, structure, distribution and transportation. Use energy supply synthesize radar comparison chart in certain time period. From energy security, economy, clean and efficiency, analyze the benefit comparisons of Chinese energy supply and demand pattern. This energy supply and demand pattern model will give one certain theoretical analysis and practice reference to the further high proportion of renewable energy. 展开更多
关键词 High Proportion of Renewable Energy Supply Inner and Outer Element Power Grid Affection Supply and demand pattern
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Research on design methodology for railway freight service combination plans to meet diverse demands
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作者 Yao Wang 《Railway Sciences》 2023年第4期525-538,共14页
Purpose–Facing the diverse needs of large-scale customers,based on available railway service resources and service capabilities,this paper aims to research the design method of railway freight service portfolio,selec... Purpose–Facing the diverse needs of large-scale customers,based on available railway service resources and service capabilities,this paper aims to research the design method of railway freight service portfolio,select optimal service solutions and provide customers with comprehensive and customized freight services.Design/methodology/approach–Based on the characteristics of railway freight services throughout the entire process,the service system is decomposed into independent units of service functions,and a railway freight service combination model is constructed with the goal of minimizing response time,service cost and service time.A model solving algorithm based on adaptive genetic algorithm is proposed.Findings–Using the computational model,an empirical analysis was conducted on the entire process freight service plan for starch sold from Xi’an to Chengdu as an example.The results showed that the proposed optimization model and algorithm can effectively guide the design of freight plans and provide technical support for real-time response to customers’diversified entire process freight service needs.Originality/value–With the continuous optimization and upgrading of railway freight source structure,customer demands are becoming increasingly diverse and personalized.Studying and designing a reasonable railway freight service plan throughout the entire process is of great significance for timely response to customer needs,improving service efficiency and reducing design costs. 展开更多
关键词 Diverse demands Service pattern Service quality Continuous clustering
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消费新场景的生成逻辑、理论内涵与实践进路 被引量:15
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作者 叶胥 唐子怡 《消费经济》 北大核心 2025年第4期1-13,共13页
在消费升级与经济高质量发展背景下,消费新场景成为激发内需、推动新旧动能转换的核心引擎。本文从“消费环境-消费情境-消费情景-消费场景”这一动态发展路径出发,基于新型消费发展趋势,解析消费新场景的生成逻辑。消费新场景囊括重视... 在消费升级与经济高质量发展背景下,消费新场景成为激发内需、推动新旧动能转换的核心引擎。本文从“消费环境-消费情境-消费情景-消费场景”这一动态发展路径出发,基于新型消费发展趋势,解析消费新场景的生成逻辑。消费新场景囊括重视价值共创与体验优化、强调要素重构与效用叠加、基于新需求导向的新供给支撑三个特征,具有扩大消费束、增加消费效用和促进消费的个性化三大功能,形成以消费者、生产者、场景搭建为三大核心支点的动态交互和价值共生的运行生态系统。消费新场景在搭建过程中会呈现系统集成、载体生成、内核组成及多维合成四大表现,本文运用该四大表现分析现实实践后,发现消费新场景的打造需融汇多元复合生态,避免品牌效应陷阱;树立可持续消费观,减少场景资源浪费;找准场景设计内核,拒绝同质内容产出;合理利用数字技术,防范本末倒置误区。由此提出针对性建议:一是发挥首发经济优势构建多元业态,二是优化税收与数字基建政策激发市场活力,三是以大型活动营造开放包容空间,四是强化区域文化品牌认同,五是平衡技术应用与文化内核。 展开更多
关键词 消费新场景 消费升级 新型消费 消费需求 体验消费
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