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Analysis on the Economical and Intensive Utilization of Regional Construction Land in Zunyi City of Guizhou Province
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作者 兰安军 王昌浩 +1 位作者 钟九生 秦微 《Agricultural Science & Technology》 CAS 2017年第6期1133-1137,共5页
Taking Zunyi City of Guizhou Province as research area, the research performed spatial dynamic analysis and elastic coefficient method to evaluate the e- conomical and intensive utilization of the regional constructio... Taking Zunyi City of Guizhou Province as research area, the research performed spatial dynamic analysis and elastic coefficient method to evaluate the e- conomical and intensive utilization of the regional construction land, and to discuss the decision direction for economical and intensive utilization of the regional con- struction land. The results showed that, the population based land utilization both in Zunyi and the city districts and counties indicated extensive trend. The economy- based land utilization in Zunyi City, as well as in Huichun, Zunyi and Tongzi County presented intensive trend, however the other districts and counties were in extensive tendency. It concluded that the economical and intensive utilization of construction land should be focused on the rural collective construction land, and the potential tapping of rural collective construction land in rocky desertification area should be the first priority, otherwise, the regional economic development was unbalanced be- tween different district and county in Zunyi. 展开更多
关键词 Economical and intensive utilization Elastic coefficient Spatial dynamicanalysis Zunyi City
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Evaluation of Intensive Land Utilization based on Anti-planning Concept
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作者 WENG Dalai 《Journal of Landscape Research》 2012年第11期23-26,28,共5页
Based on the gist of anti-planning,evaluation standards and methods of intensive land utilization were re-examined according to the inverse planning procedures.Significant role of compulsory non-development zone(simil... Based on the gist of anti-planning,evaluation standards and methods of intensive land utilization were re-examined according to the inverse planning procedures.Significant role of compulsory non-development zone(similar to the traditional"non-construction land")among the planning fruits in the intensive utilization of urban land resources and relevant index weights in the evaluation system were re-weighed.In land evaluation,relevant control indexes of compulsory non-development zone were first calculated and evaluated,healthy and sustainable development coefficients of land were obtained and regarded as the core content of the whole evaluation system. 展开更多
关键词 EVALUATION of intensive LAND utilization Anti-planning LANDSCAPE safety pattern HEALTHY and sustainable development
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Effects of harvest intensity on the marketable organ yield,growth and reproduction of non-timber forest products(NTFPs):implication for conservation and sustainable utilization of NTFPs 被引量:1
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作者 Ting Zhang Lizhong Yu +1 位作者 Yuan Man Qiaoling Yan 《Forest Ecosystems》 SCIE CSCD 2021年第4期755-764,共10页
Background:Non-timber forest products(NTFPs)are an important part of forest biodiversity,and the subsistence and trade of local people,especially in less developed countries.Because of the high ecological and economic... Background:Non-timber forest products(NTFPs)are an important part of forest biodiversity,and the subsistence and trade of local people,especially in less developed countries.Because of the high ecological and economic value,NTFPs have faced the problem of over-exploitation,and the key to solve this problem is to determine the feasible way of sustainable utilization of NTFPs.Harvest intensity is one of the most important and easily controlled utilization factors,which can greatly influence the plant individual survival,growth and reproductive performances,and even the population structure and dynamics.Therefore,we chose two common and important NTFPs species with different marketable parts(i.e.,Acanthopanax senticosus with tender leaves and Aralia elata with tender buds)as our study objects.Aiming to determine the optimum harvest intensity for sustainably utilizing both NTFPs species,five levels of harvest intensity treatments(i.e.,control,light,medium,high and severe)were designed to assess the effects of harvest intensity on their marketable organ yield,plant growth and reproductive performances.Results:The biomass growth rates of marketable organ and plant growth of A.senticosus under light harvest intensity treatment were significantly higher than those under other harvest intensities.The plant height growth and 1000-seed weight of A.elata under severe harvest intensity treatment were significantly lower than those under control treatment.Conclusions:The light harvest intensity with 25% leaf removal and the high harvest intensity with all terminal buds harvested are the optimum harvest intensity to maintain the sustainable utilization of A.senticosus and A.elata,respectively.These findings could provide managers with basic but practical guidance for making decisions about the sustainable harvest management plan for the cultivated NTFPs species,and further provide a theoretical basis for managers to establish the harvest regulations for wild NTFPs species.Consequently,the local residents or communities can improve their income while ensure the sustainable development of wild NTFPs. 展开更多
关键词 Araliaceae family Non-timber forest products Sustainable utilization Harvest intensity Plant regeneration Marketable organ yield
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A Study on the Contribution of Different Food Sources to Shrimp Growth in an Intensive Fenneropenaeus chinensis Pond
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作者 SU Yuepeng MA Shen TIAN Xiangli DONG Shuanglin 《Journal of Ocean University of China》 SCIE CAS 2008年第4期453-456,共4页
Stable isotope methods can be used to determine the food sources and prey items of aquatic organisms accurately and reliably. This study examined the relative contribution of artificial foods (the formulated feed and... Stable isotope methods can be used to determine the food sources and prey items of aquatic organisms accurately and reliably. This study examined the relative contribution of artificial foods (the formulated feed and Arternia) and natural foods to shrimp growth in an intensive Fenneropenaeus chinensis pond by using carbon and nitrogen stable isotopes. The results showed that the nutrition utilization efficiency of the harvested shrimp was low, only 33.18% of feed nitrogen and 21.73% of feed carbon being converted to shrimp flesh, Our stable isotope results showed that the shrimp obtained nutrition for maximum growth from artificial foods, whose contribution was 93.5%, with the remaining attributed to the natural foods. However, there was 0.94t harvested shrimp derived from natural foods (the rest of 13.56t harvested shrimp derived from artificial foods) in lha intensive pond with a shrimp production of 14.50 tha^-1. Therefore, unit area shrimp production can be increased by increasing the contribution proportion of natural foods in intensive shrimp farming. 展开更多
关键词 shrimp pond nutrition utilization stable isotope CONTRIBUTION intensive
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Impact of Greenization on the Marginal Utility of Intensity of Carbon Emissions and Factors Affecting it in China
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作者 Yu Liu Ruiting Jiao +1 位作者 Liyao Zhao Kai Liu 《Energy Engineering》 EI 2021年第2期363-378,共16页
The impact of greenization on the marginal utility of the intensity of carbon emissions in China and factors influ-encing this relationship are explored in this study.China’s level of greenization is evaluated by usi... The impact of greenization on the marginal utility of the intensity of carbon emissions in China and factors influ-encing this relationship are explored in this study.China’s level of greenization is evaluated by using an index system developed based on the comprehensive index method.The intensity of carbon emissions is determined by using the standards for the coefficients of conversion of coal equivalent and coefficients of carbon emission.The impact of greenization on the marginal utility of the intensity of carbon emissions is then evaluated by using an elastic formula and factors affecting this relationship are verified by regression analysis.The results are as fol-lows:(1)China’s level of greenization has exhibited a trend of constant increase.The intensity of carbon emissions has followed a continual downward trend while the impact of greenization on the marginal utility of the intensity of these emissions has been declining.(2)Urbanization as well as scientific and technological developments have slowed the reduction in the marginal utility of the intensity of carbon emissions,whereas the structure of energy consumption has expedited it under the diminishing impact of greenization.The standard of living of the popu-lation,intensity of environmental regulation,and environmental quality have had different influences under dif-ferent conditions. 展开更多
关键词 Greenization carbon emission intensity marginal utility influential factor
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Evaluation of Economical and Intensive Use of Construction Land in a County Town:A case study of Wan’an County,Ji’an City
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作者 YU Zhijie 《Journal of Landscape Research》 2024年第1期51-54,共4页
Taking the changes of construction land in Wan’an County over the years as the research object,the quantity and spatial characteristics of construction land in Wan’an County were analyzed,and the overall situation a... Taking the changes of construction land in Wan’an County over the years as the research object,the quantity and spatial characteristics of construction land in Wan’an County were analyzed,and the overall situation and regional differences of construction land utilization in Wan’an County were revealed.From the aspects of main influencing factors such as land use structure,land use intensity,land input intensity and output benefit,an evaluation indicator system was established to evaluate the economical and intensive use level of construction land in Wan’an County.The results show that the score of the economical and intensive use level of construction land in Wan’an County was 56.92,which was the lowest among all the districts and counties in Ji’an City.Based on the evaluation results,the corresponding economizing and intensive strategies were put forward,and the safeguard measures for its implementation were explored.The purpose is to provide some support for the preparation of territorial spatial planning,the delineation of urban development boundaries,and the potential exploitation of construction land stock,hoping to improve the utilization efficiency and benefit of construction land in Wan’an County,and promote the economic growth of Wan’an County to the stage of high-quality development. 展开更多
关键词 Construction land Economical and intensive utilization EVALUATION
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Efficient utilization of ecological and cultural-tourism resources:Taking Guangzhou Cultural Park as an example
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作者 XU Shu-sheng SUN Qing-yang CHEN Mian-run 《Ecological Economy》 2024年第3期278-289,共12页
Land space is precious resource and carrier of various economic activities.Ecosystem Product Value Realization and Cultural Tourism is new economic growth point for green and low-carbon development.It is necessary to ... Land space is precious resource and carrier of various economic activities.Ecosystem Product Value Realization and Cultural Tourism is new economic growth point for green and low-carbon development.It is necessary to study how to intensively and efficiently utilize ecological and cultural-tourism resources under"Three zones three lines for land use"(3Z3L),which is basic land space planning policy.However,there are few research and cases due to difficulties of interdisciplinary research.This article adopts the methods of policies research,graphic analysis,and visiting,to study efficient utilization of ecological and cultural-tourism resources.This study found that the development of land spaces of ecology,agriculture,and urban areas is 3D trend,multi-purpose resource utilization can be achieved by improving the utilization efficiency of 3D space and differentiating spatial utilization in different periods.Taking Guangzhou Cultural Park as an example,the research object has improved the efficiency of ecological and cultural-tourism resource utilization by its managements and technology,such as“house under the tree,tree inside the house”.However,there are shortcomings just as planning and protection policies with it.We proposed to optimize the spatial planning and regulations,and improve the protection of overlapping areas of 3Z3L by planning and regulations,improve the utilization efficiency of ecological and cultural-tourism space,meet the urban young people's multiple needs such as culture and ecology in 3D space,use new technologies to improve ecological services quality such as biological methods,strengthen the coordination of multiple management departments with the concept of nature based solutions,develop the“Reversed Transmission Effect”,keep the boundary of urban development strictly. 展开更多
关键词 culture-tourism three zones three lines intensive utilization of resources
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Study on the Evaluation of Intensive Land Use in Kaiyang County Based on DPSIR-TOPSIS Model
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作者 LYU Guangbin 《外文科技期刊数据库(文摘版)自然科学》 2021年第3期035-038,共7页
Land resources provide society with the necessary means of production and living for its development. The study takes Kaiyang County on the Yunnan-Guizhou Plateau as the research object, uses the DPSIR-TOPSIS model to... Land resources provide society with the necessary means of production and living for its development. The study takes Kaiyang County on the Yunnan-Guizhou Plateau as the research object, uses the DPSIR-TOPSIS model to construct the land intensive use evaluation system, and calculates the land intensive degree of Kaiyang County in 2014-2018. The results show that the intensive land use in Kaiyang County shows an upward trend, and the intensive land use has been improved. The research results can provide reference for intensive land use and effective management. 展开更多
关键词 intensive utilization DPSIR-TOPSIS Kaiyang County
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海上风电与海洋牧场融合发展研究现状及展望
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作者 黎静华 田伟 +6 位作者 王明燕 杨文涛 黎博 李畸勇 韦善阳 谢玲玲 兰飞 《中国电机工程学报》 北大核心 2026年第5期1966-1979,I0019,共15页
海上风电与海洋牧场的融合是实现海洋资源高效利用、推动能源结构转型的关键方略。然而,现有研究尚缺乏对海上风电与海洋牧场融合模式的系统性分析,特别是围绕电气工程领域的应用和研究前景。针对此问题,该文综述了海上风电与海洋牧场... 海上风电与海洋牧场的融合是实现海洋资源高效利用、推动能源结构转型的关键方略。然而,现有研究尚缺乏对海上风电与海洋牧场融合模式的系统性分析,特别是围绕电气工程领域的应用和研究前景。针对此问题,该文综述了海上风电与海洋牧场融合的研究现状及发展趋势。从布局优化、生态影响、技术发展及示范应用等方面进行了系统梳理和深入分析,评估技术、经济和政策层面的主要挑战;同时,分析了结构、空间和功能3种融合模式,提出在电气工程领域的关键问题与技术路线;并展望未来研究方向,以期为海上风电与海洋牧场的进一步发展提供理论与实践指导。研究成果为促进海上风电与海洋牧场的融合发展提供了重要参考。 展开更多
关键词 海上风电 海洋牧场 智慧用海 集约用海 产业融合
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华北平原粮食主产区耕地利用绿色转型与集约水平的耦合协调测度及时空演变
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作者 王洪佳 唐秀美 +2 位作者 王瑷玲 高莉娜 索雅丽 《农业资源与环境学报》 北大核心 2026年第2期335-344,共10页
如何在提高耕地集约利用水平的同时推进耕地利用绿色转型,是耕地可持续利用的重要挑战。本研究通过构建耕地利用绿色转型与集约水平耦合协调理论框架与分析方法,以华北平原7省(市)76个城市为例,评估2010—2020年区域耕地利用绿色转型程... 如何在提高耕地集约利用水平的同时推进耕地利用绿色转型,是耕地可持续利用的重要挑战。本研究通过构建耕地利用绿色转型与集约水平耦合协调理论框架与分析方法,以华北平原7省(市)76个城市为例,评估2010—2020年区域耕地利用绿色转型程度与集约水平,采用耦合协调度模型分析二者的耦合协调水平,利用空间自相关分析耦合协调水平的空间集聚特征。结果显示:2010—2020年研究区耕地利用绿色转型呈现波动上升的趋势,总体增幅为3.77%,空间分布整体呈现中心高、四周低的特征。2010—2020年研究区耕地利用集约水平呈现上升的趋势,总体增幅为55.80%,集约水平较高的区域主要集中在研究区中部地区。2010—2020年研究区耕地利用绿色转型程度与集约水平的耦合协调指数整体呈现上升趋势,总体增幅为12.65%,协调度较高的区域逐渐增多,主要集中在河南省东部、山东省西北部以及江苏省中部。耕地利用绿色转型与集约水平耦合协调度存在空间集聚性。研究揭示了华北平原耕地利用绿色转型与集约发展的协同提升趋势,但区域差异显著,建议通过优化绿色补贴政策、强化技术推广与区域协同机制,推动耕地利用向高效、生态、可持续方向转型。 展开更多
关键词 耕地利用 绿色转型 集约 耦合协调 华北平原
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雄安新区地下综合管廊建设关键技术创新与应用
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作者 张文明 张利峰 +3 位作者 王斐 路海亮 禹海涛 李俊奇 《隧道建设(中英文)》 北大核心 2026年第1期214-223,共10页
为解决城市地下综合管廊传统建造模式存在的地下空间开发协同不足、建管智能水平低、各设备系统物联集成差、运维能耗高、质量问题多等难题,依托雄安新区城市地下综合管廊工程,按照建设系统网络化、空间弹性化、运行智能化的综合管廊工... 为解决城市地下综合管廊传统建造模式存在的地下空间开发协同不足、建管智能水平低、各设备系统物联集成差、运维能耗高、质量问题多等难题,依托雄安新区城市地下综合管廊工程,按照建设系统网络化、空间弹性化、运行智能化的综合管廊工程体系要求,全面总结雄安新区地下综合管廊建造过程的关键技术。设计阶段,系统总结融合轨道交通、综合管廊、市政管网、地下空间以及智能设施构成的“五位一体”地下综合管廊规划设计方法;总结探索集成综合管廊、物流廊道以及地下道路的叠落共构设计方法及立体空间的设计理念,解决了有限空间综合管廊与其他市政基础设施分期建设资源消耗多、风险增大、成本过高等难题。建造阶段,总结U盾架管机及长节段、大吨位预制拼装技术的创新,介绍提廊机、架廊机、运廊车以及预应力张拉仪等大型施工成套设备的研发过程和关键步骤。运维阶段,构建开发综合管廊智慧运维平台,平台软件设计基于物联网网络(SDN)的思想,结合综合管廊结构复杂性特征,自研工业物联网节点自组网算法,设计研发包括物联网网关、中继器、采集器、控制器等在内的一系列物联网边缘接入硬件产品,解决了大规模、跨区域、运营主体多元化特点下的综合管廊运营成本高、信息传递慢、应急联动难和设备终端处置复杂的管理和技术难题。 展开更多
关键词 综合管廊 集约规划 预制拼装 U盾架管机 物联网运维
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大跨度横椭圆形波纹钢管廊损伤评价中的地震动强度指标选取
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作者 叶锡豪 苏明周 +1 位作者 祝子 郎坤 《振动与冲击》 北大核心 2026年第3期250-260,281,共12页
地震动强度指标(intensity measure,IM)是结构的损伤评价中一个重要环节,为获取波纹钢管廊结构的最优IM参数,以大跨度横椭圆形波纹钢管廊结构为研究对象,建立了4组土-波纹钢管廊结构相互作用有限元模型,结合拉丁超立方抽样技术和增量动... 地震动强度指标(intensity measure,IM)是结构的损伤评价中一个重要环节,为获取波纹钢管廊结构的最优IM参数,以大跨度横椭圆形波纹钢管廊结构为研究对象,建立了4组土-波纹钢管廊结构相互作用有限元模型,结合拉丁超立方抽样技术和增量动力分析方法,通过大量运算建立横椭圆形波纹钢管廊结构的易损性模型。以结构不同方向的相对变形率作为损伤指标(damage measure,DM),对21个常见IM参数的有效性、实用性、效益性进行考虑。同时引入随机森林(random forest,RF)算法模型和沙普利可加解释(Shapley additive explanations,SHAP)方法,讨论不同IM与DM的相关性。结果表明:考虑结构特性的速度型指标效益性最好,比值型指标表现最差,速度型指标的效益性明显优于加速度型指标以及位移型指标;速度型指标与DM相关性普遍较好,是适合用于大跨度横椭圆形波纹钢管廊结构损伤评价的IM;采用不同的DM会对易损性分析结果造成影响,推荐采用竖向相对变形率作为结构的损伤指标。 展开更多
关键词 波纹钢管廊结构 地震动强度指标(IM) 易损性分析 损伤指标(DM) 损伤评价
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耕地集约利用与农业低碳发展时空耦合的机理检验与演化分析
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作者 陈弘 曲朝鹏 +1 位作者 于慧斌 周为 《生态经济》 北大核心 2026年第1期149-157,共9页
农业绿色发展是实施乡村振兴战略的重要引领,耕地集约利用和农业低碳发展分别从经济效益和生态效益两个角度反映了农业绿色发展的“一体两面”。论文在剖析耕地集约利用和农业低碳发展两个系统的耦合协调机理并进行实证检验的基础上,运... 农业绿色发展是实施乡村振兴战略的重要引领,耕地集约利用和农业低碳发展分别从经济效益和生态效益两个角度反映了农业绿色发展的“一体两面”。论文在剖析耕地集约利用和农业低碳发展两个系统的耦合协调机理并进行实证检验的基础上,运用耦合协调度模型测算2011—2021年我国省域耕地集约利用和农业低碳发展的耦合协调度,并利用趋势面模型、核密度估计和泰尔指数分析其时空演化特征。结果表明:(1)研究期间两系统之间的耦合协调度呈显著的上升趋势,耦合协调度整体上从初级协调上升为良好协调,其中东部地区耦合协调度最高,西部地区耦合协调度增长幅度最大。(2)两系统的耦合协调关系存在明显的“北高南低,东高西低”特征,且南北方向的空间结构差异更为明显,整体差异在逐渐缩小,各区域的耦合协调水平趋于集中发展。(3)耦合协调度整体上的差距逐渐缩小,区域间差距不断降低,地区差异主要由区域内差异导致,西部地区区域内差异最显著,东北部地区区域内差异呈上升趋势,其他地区均呈下降趋势。基于此,建议各省份加强保护性耕作方式推广、持续做好耕地面源污染防治、因地制宜制定区域发展策略、推动农业科技创新与应用。 展开更多
关键词 农业绿色发展 耕地集约利用 农业低碳发展 耦合协调度 机理检验 时空演化特征
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基于TOPSIS法的山西省沿黄四市水资源节约集约利用水平研究
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作者 李扬 牛永华 《水资源开发与管理》 2026年第1期3-9,共7页
为科学评价山西省沿黄重点地区的水资源节约集约利用水平,实现水资源高效利用,以山西省沿黄四市为研究区,选取与水资源节约集约利用密切相关的19项指标,建立了“经济社会-水资源-生态环境”系统评价指标体系,综合主成分分析法、熵权法和... 为科学评价山西省沿黄重点地区的水资源节约集约利用水平,实现水资源高效利用,以山西省沿黄四市为研究区,选取与水资源节约集约利用密切相关的19项指标,建立了“经济社会-水资源-生态环境”系统评价指标体系,综合主成分分析法、熵权法和CRITIC法计算指标权重,并利用TOPSIS法评价了研究区2015—2022年水资源节约集约利用水平。结果表明,研究区水资源节约集约利用整体水平为“中等”,并呈上升趋势,预计未来几年可达到“较好”等级。该研究成果可为山西省沿黄重点地区的水资源配置提供参考。 展开更多
关键词 沿黄四市 水资源节约集约利用 TOPSIS法
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客户稳定性对企业创新质量的影响
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作者 章铁生 黄家翔 《安徽工业大学学报(自然科学版)》 2026年第1期87-98,共12页
以2007—2023年沪深A股上市公司为样本,基于前五大客户数据,实证检验客户稳定性对企业创新质量的影响,并考察管理费用率、财务费用率与产能利用率的中介机制,进一步从企业竞争能力与要素密集度视角进行异质性分析。结果表明:客户稳定性... 以2007—2023年沪深A股上市公司为样本,基于前五大客户数据,实证检验客户稳定性对企业创新质量的影响,并考察管理费用率、财务费用率与产能利用率的中介机制,进一步从企业竞争能力与要素密集度视角进行异质性分析。结果表明:客户稳定性显著促进企业创新质量提升,其作用机制主要通过降低创新相关成本(降本)和提升供需匹配效率(增效)2条路径实现;在劳动密集型行业及市场竞争能力较弱的企业中,客户稳定性对创新质量的促进作用更为明显。据此,企业应将长期客户关系提升至战略高度,依托稳定客户群的知识与需求优势,优化资源配置与运营效率,并应结合企业类型与行业特征制定差异化的客户关系策略,将客户稳定性转化为持续提升创新质量和核心竞争力的关键动力。本研究拓展了企业创新质量前因与客户稳定性经济后果的理论视角,为企业通过构建稳定客户关系实现高质量创新提供了理论支持和大样本经验证据。 展开更多
关键词 客户稳定性 创新质量 供应链 产能利用率 知识溢出 资源整合 要素密集度 市场竞争
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Production,utilization,and quality of irrigated grasses and legumes in the Mountain West USA under mob stocking or mowing at the same defoliation frequency and intensity
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作者 Jennifer W.MacAdam Brody Maughan Xin Dai 《Grassland Research》 2025年第1期31-40,共10页
Background:Feed is the most costly input for US ruminant livestock production systems,and increasing the utilization efficiency of irrigated forage systems can improve system profitability.This study assessed the prod... Background:Feed is the most costly input for US ruminant livestock production systems,and increasing the utilization efficiency of irrigated forage systems can improve system profitability.This study assessed the production,utilization,and quality of 22 intensively managed perennial grasses and legumes.Methods:Forages were cultivated as monocultures under irrigation and subjected to mob stocking or similarly frequent and intense mowing for 2 years at 6‐week intervals between May and September.Twenty‐two grasses and legumes were randomly assigned to adjacent 1.5‐m‐wide×9‐m‐long split subplots within each whole plot of eight replications,and the eight replications were grouped into four pairs,with the two replications per pair randomly assigned to defoliation either by grazing or mowing.Results:Seven mostly warm‐season grasses did not persist following the first defoliation,and accumulation for three legume species could be evaluated only twice in Year 1.For the 12 remaining forage species defoliated four times in both years,defoliation management did not affect dry matter accumulation or removal,but utilization was 10%greater under grazing than mowing(p=0.0031).Conclusions:Under 6‐week‐long rest periods,numerous irrigated cool‐season grasses and temperate legumes were tolerant of repeated mob grazing. 展开更多
关键词 forage herbage accumulation grazing frequency grazing intensity pasture utilization
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中国化肥减量增效行动与技术研究 被引量:16
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作者 李娜 田云龙 +3 位作者 张蕾 王胜涛 朱昌雄 李红娜 《农业资源与环境学报》 北大核心 2025年第1期1-10,共10页
化肥是当代农业的重要生产资料,在农业生产中不可替代,但化肥的不合理施用会对环境造成潜在威胁。本文对我国近年来出台的系列化肥减量增效行动和政策、国家统计年鉴数据和相关的研究进展进行了梳理总结。结果表明:我国的化肥减量增效... 化肥是当代农业的重要生产资料,在农业生产中不可替代,但化肥的不合理施用会对环境造成潜在威胁。本文对我国近年来出台的系列化肥减量增效行动和政策、国家统计年鉴数据和相关的研究进展进行了梳理总结。结果表明:我国的化肥减量增效行动已初具成效,表现为2015—2022年的8年间,化肥用量减少15.7%,而粮食增产3.9%;化肥施用结构趋向合理化,表现为氮肥用量持续减少,复合肥用量持续增加;我国的化肥施用强度也有所下降,2022年化肥施用强度(298.8 kg·hm^(-2))比2015年减少62.2 kg·hm^(-2),但施肥强度仍有进一步减量空间;化肥减量、养分利用、元素循环转化等方面的研究有望为提高化肥利用率、推进减量增效行动提供基础科学依据。本文为我国进一步开展科学的化肥减量增效行动提出政策和管理建议,以期为我国的化肥减量增效行动的现状和未来的行动方针提供科学依据和参考。 展开更多
关键词 化肥 氮肥利用率 减量增效 有机肥替代 施肥强度
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城市社区嵌入式公共体育服务的内涵阐释、实践探索与推进策略 被引量:5
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作者 李承伟 宋述光 +2 位作者 刘转青 赵子豪 梁木军 《体育科学》 北大核心 2025年第2期67-76,共10页
城市社区嵌入式公共体育服务是破解群众“健身去哪儿”难题、实现公共体育服务公平可及的重要突破口。采用文献资料分析、实地考察等方法,系统阐释城市社区嵌入式公共体育服务的内涵特征,梳理国内政策演进脉络,总结地方实践经验与现实困... 城市社区嵌入式公共体育服务是破解群众“健身去哪儿”难题、实现公共体育服务公平可及的重要突破口。采用文献资料分析、实地考察等方法,系统阐释城市社区嵌入式公共体育服务的内涵特征,梳理国内政策演进脉络,总结地方实践经验与现实困境,并提出推进策略。研究发现,嵌入式公共体育服务发展以空间利用、供需匹配、集约建设三重逻辑为出发点与落脚点,历经萌芽、丰富与提升和提档升级3个阶段,实现了发展内涵的重要转变。地方实践表明,党建引领与制度支撑、多元主体协同推进、与城市更新深度融合、数据要素赋能以及智慧场景创新是推动服务发展的宝贵经验。当前,嵌入式公共体育服务仍面临诸多现实挑战:资源禀赋不足、空间权属模糊,协同链条脆弱、服务输出趋同,政策尚不健全、监管机制缺位,市场动力孱弱、长效运营乏力。为此,可以通过科学规划布局、整合存量资源、完善政策保障、拓宽筹资渠道、强化数智赋能等策略,推动城市社区嵌入式公共体育服务的可持续发展。 展开更多
关键词 社区公共体育服务 嵌入式服务 空间利用 供需匹配 集约建设
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建设用地类型集约利用对城市碳排放影响的异质性——以长三角城市群为例
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作者 柴铎 孙永豪 +1 位作者 尚俊妤 姜玲 《经济地理》 北大核心 2025年第8期73-81,共9页
文章利用双向固定效应模型和GTWR模型,以长三角城市群为样本探究了城市产业用地、住宅用地和交通用地集约利用对城市碳排放的影响差异。结果表明:研究时段内,产业用地集约利用水平提升对城市碳排放具有正向影响,虽然当地不断推动产业绿... 文章利用双向固定效应模型和GTWR模型,以长三角城市群为样本探究了城市产业用地、住宅用地和交通用地集约利用对城市碳排放的影响差异。结果表明:研究时段内,产业用地集约利用水平提升对城市碳排放具有正向影响,虽然当地不断推动产业绿色升级改造,仍无法抵消制造业出口导向经济下单位面积土地资源和能源消耗带来的增碳作用。住宅用地集约利用度的提升对于降低城市碳排放具有显著作用,一方面缘于居民生活水平提升带来的绿色生活方式转变,另一方面缘于集约居住带来的能量损耗减少以及绿色节能建筑和管理的应用。交通用地集约利用对碳排放的影响存在分异特征,总体上具有抑制碳排放的作用,部分城市内部交通集约利用度上升表现为碳增效应。 展开更多
关键词 建设用地 产业用地 集约利用 碳排放 异质性 绿色节能建筑 长三角城市群
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深化农业水价综合改革的典型模式与对策建议 被引量:2
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作者 刘小勇 刘啸 马俊 《中国水利》 2025年第12期40-44,共5页
以深化农业水价综合改革为抓手推进现代化灌区建设,是贯彻落实党中央、国务院关于全面深化改革、保障国家粮食安全和水安全等决策部署的重要举措。针对水价形成机制、各方利益关系调整、灌区管理体制等长期困扰农业水价综合改革的难点问... 以深化农业水价综合改革为抓手推进现代化灌区建设,是贯彻落实党中央、国务院关于全面深化改革、保障国家粮食安全和水安全等决策部署的重要举措。针对水价形成机制、各方利益关系调整、灌区管理体制等长期困扰农业水价综合改革的难点问题,选取云南元谋县、宁夏利通区和山西芮城县等3个典型试点持续跟踪,提炼总结形成破解改革难题的经验模式,如:云南元谋县培育形成市场要素驱动的农业水价改革模式,宁夏利通区创新形成工程改造与机制建设“双轮驱动”的改革模式,山西芮城县形成“以大带小、分类定价”的改革模式。基于当前中央政策要求和改革试点经验,从推进现代化灌区建设、完善水价形成机制、加强试点跟踪指导等方面提出了深化农业水价综合改革的对策建议:推进现代化灌区建设,夯实水价改革的硬件基础;深化农业水价综合改革,优化水价形成机制;加强试点跟踪指导,总结提炼可推广的改革模式。研究成果可为相关研究和管理工作提供技术依据和决策参考。 展开更多
关键词 农业水价综合改革 现代化灌区建设 用水权 水资源节约集约利用
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