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Profit Incentives and Organizational Behaviour:A Comparative Evaluation of Enterprise Forms
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作者 XU Duoxin 《Management Studies》 2025年第4期180-185,共6页
This essay evaluates the behavioural dynamics generated by profit incentives and compares them with those in government-owned and charitable enterprises.Drawing on neoclassical microeconomics,agency theory,and institu... This essay evaluates the behavioural dynamics generated by profit incentives and compares them with those in government-owned and charitable enterprises.Drawing on neoclassical microeconomics,agency theory,and institutional economics,it shows how the profit motive drives cost minimization,allocative efficiency,innovation,and consumer responsiveness.Profit expectations,formalized in endogenous growth models,act as catalysts for technological progress and dynamic efficiency,while agency-theoretic governance mechanisms align managerial incentives with shareholder interests.In contrast,government-owned enterprises operate under multi-objective welfare functions,often constrained by soft budget expectations,political interference,and X-inefficiencies that dilute efficiency.Charitable organizations,structured by the non-distribution constraint,emphasize social trust,equity,and mission fulfilment,supported by warm-glow altruism but constrained by free-rider problems and underfunding.A comparative evaluation suggests that profit-driven firms outperform in competitive markets producing private goods,whereas government and charitable forms play essential roles in addressing market failures and providing public or credence goods.The analysis affirms the institutionalist principle that ownership and governance structures must be aligned with the nature of the goods or services delivered. 展开更多
关键词 profit incentives organizational behaviour government-owned enterprises charitable organizations allocative efficiency innovation agency theory institutional economics
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Construction of building energy conservation incentive policies under government regulation: Based on the subjects' behavior analysis
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作者 GUO Han-ding ZHANG Yin-xian +1 位作者 ZHAO Qian-qian REN Shao-ming 《Ecological Economy》 2017年第3期227-233,共7页
Building energy efficiency is a long-term strategy to achieve sustainable development, but the inconsistencies of main interests during the implementation lead to the need for government regulation in building energy ... Building energy efficiency is a long-term strategy to achieve sustainable development, but the inconsistencies of main interests during the implementation lead to the need for government regulation in building energy conservation. Implementation of building energy efficiency of government regulation covers three aspects of construction and involves relevant participators, so the paper analyzes interests and roles of the related subjects in building energy saving, explore the motivations and its conversion mechanism of each player, and dissect the game relationship of associated earnings of developers' and consumers' behaviors selection under government control. Finally, the paper proposes basic requirements of building incentive policies for related subjects under government control to regulate the main behaviors of subjects in building energy efficient buildings and achieve energy efficiency goals and balance of all parties' benefits. 展开更多
关键词 building energy efficiency subject behaviors benefit analysis government regulation incentive policies
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The energy efficiency and environmental protection campaign demands policy incentives
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《中国汽车(英文版)》 2007年第9期2-,共1页
The hottest topic now among Europe's automotive industry is CO2. The European Union has set the goal. By 2012, all Europe-based car makers would have to reduce the per car CO2 level to as low as 120-130g/km from t... The hottest topic now among Europe's automotive industry is CO2. The European Union has set the goal. By 2012, all Europe-based car makers would have to reduce the per car CO2 level to as low as 120-130g/km from the current 160g/km. 展开更多
关键词 The energy efficiency and environmental protection campaign demands policy incentives
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Urban Land Use Efficiency and Contributing Factors in the Yangtze River Delta Under Increasing Environmental Restrictions in China 被引量:2
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作者 YANG Qingke WANG Lei +3 位作者 QIN Xianhong FAN Yeting WANG Yazhu DING Linlin 《Chinese Geographical Science》 SCIE CSCD 2022年第5期883-895,共13页
Evaluating urban land use efficiency(ULUE) provides insights into the interactions between land use systems and their external environment. Specifically, changes in ULUE are important for monitoring urban transformati... Evaluating urban land use efficiency(ULUE) provides insights into the interactions between land use systems and their external environment. Specifically, changes in ULUE are important for monitoring urban transformation in developing countries. In this study, using a traditional input-output index model, we incorporated slack-based measurements and undesirable outputs into a SBM-UN(slack-based measure-undesirable) model to investigate ULUE within the context of increasing environmental restrictions in China. The model was used to estimate the ULUE of 26 cities in the highly developed urban agglomeration of the Yangtze River Delta from 2000 to2018. The average ULUE in the Yangtze River Delta was relatively low compared to that of developed city regions in the European Union(EU) and North America and exhibited a U-shaped curve over the study period. Incorporating undesirable outputs, such as environmental pollution, into the model reduced ULUE by 19.06%. ULUE varied spatially, with the kernel density estimation exhibiting a bimodal distribution. Efficiency decomposition analysis showed that scale efficiency made a greater contribution to ULUE than pure technical efficiency. Based on our findings, recommended approaches to improve ULUE include optimizing factor allocation, reducing undesirable outputs, and increasing the effective output per land unit. The study suggests that ULUE and the SBM-UN model are useful planning tools for sustainable urban development. 展开更多
关键词 urban land use efficiency(ULUE) environmental restriction efficiency decomposition kernel density estimation SBM-UN(slack-based measure-undesirable)model Yangtze River Delta China
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Spatial-temporal Characteristics of Green Development Efficiency and Influencing Factors in Restricted Development Zones:A Case Study of Jilin Province,China 被引量:2
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作者 LI Ping TONG Lianjun +1 位作者 GUO Yanhua GUO Fuyou 《Chinese Geographical Science》 SCIE CSCD 2020年第4期736-748,共13页
Green development is an important issue of sustainable development in China.Due to the relatively backward economy and the fragile ecological environment,restricted development zones need to embrace green development.... Green development is an important issue of sustainable development in China.Due to the relatively backward economy and the fragile ecological environment,restricted development zones need to embrace green development.Taking 38 counties in Jilin Province as the empirical research objects,and based on cross-sectional data for each county in 2005,2010,and 2015,we accurately depicted the spatiotemporal evolutionary characteristics of green development efficiency(GDE)in restricted development zones of Jilin Province using the slacks-based measure-data envelope analysis(SBM-DEA)model.Moreover,the factors that influence GDE were further analyzed using the Tobit model.We found that:first,GDE showed a V-shaped trend in restricted development zones of Jilin Province.The differences in GDE in the eastern,central,and western Jilin Province increased gradually.Second,76%of counties in the restricted development zones had high or higher efficiencies.The resource-based cities were the main areas with low or lower GDE.Third,the economic development level was the core factor affecting GDE.Urbanization level had a significant negative effect on GDE in the restricted development zones.The effect of technological innovation level on GDE fluctuated,and we found that a‘backward mechanism’of technological innovation was beginning to form.Industrial structure and environmental governance had no significant effects on GDE. 展开更多
关键词 green development efficiency spatiotemporal evolution influencing factor restricted development zones Jilin Province
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Examination of the molecular control of ruminal epithelial function in response to dietary restriction and subsequent compensatory growth in cattle 被引量:1
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作者 Emma O'Shea Sinead M. Waters +2 位作者 Kate Keogh Alan K. Kelly David A. Kenny 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2017年第1期107-118,共12页
Background: The objective of this study was to investigate the effect of dietary restriction and subsequent compensatory growth on the relative expression of genes involved in volatile fatty acid transport, metabolis... Background: The objective of this study was to investigate the effect of dietary restriction and subsequent compensatory growth on the relative expression of genes involved in volatile fatty acid transport, metabolism and cell proliferation in ruminal epithelial tissue of beef cattle. Sixty Holstein Friesian bulls(mean liveweight 370 ± 35 kg;mean age 479 ± 15 d) were assigned to one of two groups:(i) restricted feed allowance(RES; n = 30) for 125 d(Period 1) followed by ad libitum access to feed for 55 d(Period 2) or(ii) ad libitum access to feed throughout(ADLIB; n = 30). Target growth rate for RES was 0.6 kg/d during Period 1. At the end of each dietary period, 15 animals from each treatment group were slaughtered and ruminal epithelial tissue and liquid digesta harvested from the ventral sac of the rumen. Real-time q PCR was used to quantify m RNA transcripts of 26 genes associated with ruminal epithelial function. Volatile fatty acid analysis of rumen fluid from individual animals was conducted using gas chromatography.Results: Diet × period interactions were evident for genes involved in ketogenesis(BDH2, P = 0.017), pyruvate metabolism(LDHa, P = 0.048; PDHA1, P = 0.015) and cellular transport and structure(DSG1, P = 0.019; CACT, P = 0.027). Ruminal concentrations of propionic acid(P = 0.018) and n-valeric acid(P = 0.029) were lower in RES animals, compared with ADLIB, throughout the experiment. There was also a strong tendency(P = 0.064)toward a diet × period interaction for n-butyric with higher concentrations in RES animals, compared with ADLIB, during Period 1.Conclusions: These data suggest that following nutrient restriction, the structural integrity of the rumen wall is compromised and there is upregulation of genes involved in the production of ketone bodies and breakdown of pyruvate for cellular energy. These results provide an insight into the potential molecular mechanisms regulating ruminal epithelial absorptive metabolism and growth following nutrient restriction and subsequent compensatory growth. 展开更多
关键词 Beef cattle Compensatory growth Feed efficiency Nutrient restriction Rumen epithelium
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税收优惠对高新技术企业研发创新效率影响研究
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作者 马秀颖 姚敏 赵明璐 《经济学家》 北大核心 2026年第2期75-85,共11页
高新技术企业作为国家创新体系的关键主体,提升研发创新效率是推动经济高质量发展与构筑国家竞争新优势的核心,对高新技术企业实施精准有效的税收优惠政策以激励企业创新成为关键举措。研究发现:从数量和质量两个维度测算研发创新效率,... 高新技术企业作为国家创新体系的关键主体,提升研发创新效率是推动经济高质量发展与构筑国家竞争新优势的核心,对高新技术企业实施精准有效的税收优惠政策以激励企业创新成为关键举措。研究发现:从数量和质量两个维度测算研发创新效率,税收优惠对高新技术企业创新效率有着显著的正向影响;这种影响存在区域异质性与企业类型异质性,东部地区最为显著,国有企业受到的影响更大;这种正向影响存在滞后效应,且随着时间的推移影响逐渐减弱,在滞后三期后消失;税收优惠通过推动研发投入的增长提升企业创新效率,且研发投入和企业规模均存在门槛效应。因此,应建立面向高新技术企业研发创新效率的精准化、动态化税收政策体系,通过对创新核心区实施集群专项政策引导高端要素集聚,并构建多维效能监测动态调整机制,推动税收优惠向精准激励模式转变,全面提升高新技术企业研发创新效率。 展开更多
关键词 税收优惠 高新技术企业 创新效率 研发投入
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农业多功能开发对农户生产积极性的影响研究——基于全国冬油菜成熟期田间实际测产调查的实证
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作者 李谷成 唐晶 冯中朝 《农村经济》 北大核心 2026年第1期40-49,共10页
农业多功能开发能够助力乡村产业振兴和激发农村内生发展动力。本文基于期望效用理论,构建农户生产决策行为分析框架,并利用2022年冬油菜成熟期田间实际测产与种植户问卷调查数据,考察农业多功能开发对农户生产积极性的影响,以期为减少... 农业多功能开发能够助力乡村产业振兴和激发农村内生发展动力。本文基于期望效用理论,构建农户生产决策行为分析框架,并利用2022年冬油菜成熟期田间实际测产与种植户问卷调查数据,考察农业多功能开发对农户生产积极性的影响,以期为减少耕地撂荒及冬闲田利用等政策的制定提供参考。研究结果表明,农业多功能开发能够有效提升农户生产积极性,在利用工具变量克服内生性问题后,结论依然稳健。异质性分析发现,农业多功能开发的提升作用在还未加入合作社、平原及山区的农户中更为明显。机制分析表明,农业多功能开发通过提高农户种植收益和生产效率进而提升其生产积极性。进一步分析显示,农业多功能开发模式是影响农户生产积极性的重要因素,“油用+菜用+蜜用+观光用”功能模式的开发对油菜种植户生产积极性的提升效果最佳。由此,政府应加大对多功能开发的政策支持力度,通过培训和示范项目提高种植户的认知度和参与度;加强农业多功能技术研发与市场需求的对接,不断拓宽农户的选择边界;因地制宜探索农业多功能开发的差异化发展策略,推广多样化的开发模式,提高政策的实效性和针对性。 展开更多
关键词 多功能开发 生产积极性 种植收益 生产效率 田间实际测产 油菜
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Hainan’s New Leap: A Gateway to Shared Development
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《China Today》 2026年第3期24-25,共2页
The Hainan Free Trade Port(FTP),with the launching of island-wide special customs operations,is allowing greater convenience for overseas goods to enter the island,trying to build it into an efficient hub connecting C... The Hainan Free Trade Port(FTP),with the launching of island-wide special customs operations,is allowing greater convenience for overseas goods to enter the island,trying to build it into an efficient hub connecting China with the rest of the world.Its core appeal no longer relies solely on policy incentives but has shifted toward transparent and predictable institutional guarantees which provide stable expectations for global investors. 展开更多
关键词 free trade port ftp Efficient Hub Hainan Free Trade Port transparent predictable institutional guarantees Island wide Special Customs Operations Overseas Goods policy incentives China Global Investors
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Promoting energy efficiency reconstruction for existing buildings based on comprehensive benefit evaluation 被引量:2
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作者 GUO Han-ding ZHANG Yin-xian +1 位作者 WANG Yi-lin CUI Si-wen 《Ecological Economy》 2017年第4期332-337,共6页
The purpose of the comprehensive benefit evaluation of the existing building energy saving renovation project is to promote the healthy development of the energy saving reconstruction. Therefore, it is necessary to re... The purpose of the comprehensive benefit evaluation of the existing building energy saving renovation project is to promote the healthy development of the energy saving reconstruction. Therefore, it is necessary to reflect the value and function of incentive and restraint. The concrete embodiment is that: improving energy saving standard renovation of existing buildings, promoting the construction of energy efficiency labeling system, and strengthening the construction of government supervision system by the comprehensive benefit evaluation. 展开更多
关键词 energy efficiency reconstruction existing buildings comprehensive benefit evaluation incentive and restraint
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考虑富氧燃烧技术与需求响应的工业园区综合能源系统优化调度
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作者 覃育茗 祝云 《中国电力》 北大核心 2026年第3期48-63,共16页
在碳达峰和碳中和背景下,工业园区综合能源系统(integrated energy system,IES)因其较高的灵活性和较低的碳排放受到了广泛关注。为降低工业园区IES的碳排放,并提高工业园区IES的经济效益,构建了考虑富氧燃烧捕集技术与电转氢(power-to-... 在碳达峰和碳中和背景下,工业园区综合能源系统(integrated energy system,IES)因其较高的灵活性和较低的碳排放受到了广泛关注。为降低工业园区IES的碳排放,并提高工业园区IES的经济效益,构建了考虑富氧燃烧捕集技术与电转氢(power-to-hydrogen,P2H)技术合作以及需求响应机制的工业园区IES系统优化调度模型。首先,该模型通过对火电机组进行富氧燃烧改造来提高系统灵活性,降低火电机组碳排放;其次,通过引入P2H与富氧燃烧电厂合作,不仅提高了风光消纳量,也降低了富氧燃烧电厂供氧压力;然后,通过掺氢设备降低了能量转化过程中的损耗,实现了氢气高位利用;最后,通过引入需求响应,进一步提高IES的灵活性,降低碳排放,并基于此建立了该工业园区IES的最小成本优化调度模型。通过案例研究发现实际碳排放较碳配额低29.60%,验证了该模型的有效性,并分析了部分关键变量对工业园区IES的影响。 展开更多
关键词 综合能源系统 富氧燃烧电厂 激励型需求响应 热效率变化 P2H合作机制
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Case Study Evidence and Behavioural Analysis of Residential Energy Consumption in the UK
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作者 Sven Hallin Elizabeth Hooper Thomas Weyman-Jones 《Open Journal of Energy Efficiency》 2017年第1期14-40,共27页
This paper investigates residential energy consumption in the UK by using a novel and topical approach based on behavioural analysis. A key lesson from recent advances in behavioural economics is that the responses of... This paper investigates residential energy consumption in the UK by using a novel and topical approach based on behavioural analysis. A key lesson from recent advances in behavioural economics is that the responses of individuals to both policy incentives and uncertainty may differ from the predictions of classical rational optimising behaviour. By employing a focused case study approach using both quantitative and qualitative response analysis, it considers the motivations of residential householders in the UK to reduce fossil fuel use, with additional perspectives from UK landlords, a global environmental NGO, a senior politician, and two senior stakeholder strategy managers from a large energy company. Our interpretative behavioural analysis shows that a variety of incentives are necessary to encourage behaviour change. However, case study participants largely agree on the beneficial role of government regulation and efforts to “nudge” them in the right direction with regard to their energy use. As a means of more effectively reducing carbon dioxide emissions, we conclude that policy should focus on sustainable energy use. The findings allow us to understand why important recent policy initiatives such as the UK Green Deal failed to achieve their objectives and they suggest lessons for more effective incentive based policy making in the field of residential energy consumption. 展开更多
关键词 ENERGY Policy BEHAVIOURAL ECONOMICS incentiveS for ENERGY efficiency SUSTAINABLE ENERGY
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极端干旱及其胁迫持续对连翘光合效率的降低作用
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作者 董芳瑜 郎莹 +1 位作者 徐艳会 杨修一 《北方园艺》 北大核心 2026年第4期51-60,共10页
以连翘为试材,布设盆栽模拟试验,采用人工灌水、植物自然耗水与称重相结合的方法,设计了不同土壤极端干旱处理,测定了不同处理下的叶片光合作用和叶绿素荧光参数,研究了连翘光合效率在极端干旱下的降低过程与机制,以期为极端干旱下山地... 以连翘为试材,布设盆栽模拟试验,采用人工灌水、植物自然耗水与称重相结合的方法,设计了不同土壤极端干旱处理,测定了不同处理下的叶片光合作用和叶绿素荧光参数,研究了连翘光合效率在极端干旱下的降低过程与机制,以期为极端干旱下山地观赏植物的水分管理提供参考依据。结果表明:1)当土壤相对含水量(RSWC)降低至46.17%时,净光合速率(Pn)和水分利用效率(WUE)显著降低,光合效率降低的主要原因转为非气孔限制,将RSWC=46.17%作为连翘极端干旱的起始阈值(气孔机制转折点),界定RSWC≤46.17%为连翘极端干旱范围。2)极端干旱水分胁迫下,随着RSWC降低,Pn、WUE、PSⅡ最大光化学效率(Fv/Fm)、PSⅡ实际光化学效率(ΦPSⅡ)、最大荧光(Fm)、光化学淬灭系数(qP)显著降低,初始荧光(Fo)显著增大,表明极端干旱水分亏缺直接破坏连翘PSⅡ反应中心,抑制光合电子传递,引发光抑制而使光合效率显著降低。3)极端干旱3个水分阈值(气孔机制转折水分(RSWC1)、叶片萎蔫水分(RSWC2)、Pn趋于0时水分(RSWC3))胁迫持续28 d期间,连翘光合系统呈现“渐进-崩溃”特征,初期(<7 d),通过增大NPQ、降低qP延缓光损伤,连翘光合效率(Pn、WUE、Fv/Fm、ΦPSⅡ)均高于0;但随胁迫持续延长(14~28 d),光合效率(Pn、WUE、Fv/Fm、ΦPSⅡ)在0处波动,qP和NPQ均趋于0,连翘光合系统严重受损、自我调节机制濒临崩溃。 展开更多
关键词 极端干旱 胁迫持续 光合效率 叶绿素荧光 非气孔限制
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Factors Affecting Energy Efficiency Investments—A Case Study of Bhutan
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作者 Roshan Chhetri Young-Ho LEE +1 位作者 Duane Robinson Sumitra Pokhrel 《Journal of Electrical Engineering》 2019年第2期54-60,共7页
Energy efficiency is providing the same services consuming less energy.Less energy means less energy bill and less greenhouse emissions.Bhutan presents a unique scenario in promoting the use of energy efficiency equip... Energy efficiency is providing the same services consuming less energy.Less energy means less energy bill and less greenhouse emissions.Bhutan presents a unique scenario in promoting the use of energy efficiency equipment and investments.Bhutan enjoys availability of adequate low cost hydropower energy resource that is green and clean and enjoys cheap electrical energy.To aggravate the situation,the domestic tariffs are subsidized and even free up to 100 units in rural parts of the country.Export tariffs are determined independently according to entirely different principles.However for cooking,Bhutan imports LPG(Liquefied Petroleum Gas)from India.With increasing threats of climate change,it is reported water flow in rivers is decreasing.For energy security and related socio environmental issues,prospects of energy supply constraints and increasing demand of quality power in the country,there is a need to take appropriate policy measures which would lead to the development of indigenous,local and dispersed clean energy sources in the future.When a customer is asked to retrofit the house with energy efficiency,the owner questions oneself if the available investment resources are being directed to an effective return.Various criteria are available but all can not to be considered to come to a final decision.This paper presents an overview of many factors which affect energy efficiency investment in building in Bhutan. 展开更多
关键词 Energy efficiency POLICIES retrofits incentiveS
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小微企业所得税优惠扩围与全要素生产率提升
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作者 于井远 于海峰 魏升民 《中央财经大学学报》 北大核心 2026年第4期39-56,共18页
企业所得税优惠政策是我国支持小微企业发展的重要工具,新时代下兼具适用税率持续优化与适用主体不断扩围两个特点,现有研究较少考察适用主体不断扩围这一政策的经济效应。笔者以2017年实施的小微企业年应纳税所得额上限调整(即所得税... 企业所得税优惠政策是我国支持小微企业发展的重要工具,新时代下兼具适用税率持续优化与适用主体不断扩围两个特点,现有研究较少考察适用主体不断扩围这一政策的经济效应。笔者以2017年实施的小微企业年应纳税所得额上限调整(即所得税优惠扩围)为准自然实验,利用2016—2020年全国税收调查数据,实证考察了小微企业所得税优惠扩围对其全要素生产率提升的影响。研究发现,所得税优惠扩围有效地降低了小微企业实际税负与融资约束,从而促进了其全要素生产率的提高。机制分析表明,所得税优惠扩围后,一方面小微企业通过提升劳动资源配置效率和固定资产投资效率直接促进了企业全要素生产率的提升,另一方面还通过增强供应链上下游企业关联与强化分工间接促进了企业生产率的提升。进一步分析发现,所得税优惠扩围还显著提高了样本期间小微企业经营绩效。本文结论对于进一步优化小微企业税收优惠政策、持续打好政策组合拳具有一定的政策启示。 展开更多
关键词 所得税优惠扩围 全要素生产率 资源配置效率 供应链关联
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妊娠期高血压疾病患者血清抑制素-A脑胎盘率水平变化及对胎儿生长受限的预测价值
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作者 唐玲 戴丽丽 朱莉 《河北医学》 2026年第3期499-504,共6页
目的:探讨妊娠期高血压疾病(HDP)患者血清抑制素-A(INH-A)、脑胎盘率(CPR)水平变化及对胎儿生长受限(FGR)的预测价值。方法:选取2022年1月至2025年1月我院收治的HDP患者223例(HDP组)和同期健康孕妇120例(对照组),根据是否发生FGR将HDP... 目的:探讨妊娠期高血压疾病(HDP)患者血清抑制素-A(INH-A)、脑胎盘率(CPR)水平变化及对胎儿生长受限(FGR)的预测价值。方法:选取2022年1月至2025年1月我院收治的HDP患者223例(HDP组)和同期健康孕妇120例(对照组),根据是否发生FGR将HDP患者分为FGR组(64例)和非FGR组(159例),计算CPR和检测血清INH-A水平。以HDP患者FGR为因变量,多因素非条件Logistic回归确定其影响因素,受试者工作特征曲线分析CPR联合血清INH-A水平对其的预测效能。结果:HDP组CPR低于对照组,血清INH-A水平高于对照组,差异有统计学意义(P<0.05)。223例HDP患者FGR发生率为28.70%(64/223)。FGR组CPR低于非FGR组,血清INH-A水平高于非FGR组,差异有统计学意义(P<0.05)。HDP患者FGR的独立危险因素为子痫前期、重度子痫前期及血清INH-A水平升高,独立保护因素为CPR升高,差异有统计学意义(P<0.05)。CPR联合血清INH-A水平预测HDP患者FGR的曲线下面积为0.909,大于CPR、血清INH-A水平单独预测的0.849、0.785(P均<0.05)。结论:HDP患者血清INH-A水平升高,CPR降低,与并发FGR密切相关,联合2指标对HDP患者并发FGR具有较高的预测效能。 展开更多
关键词 妊娠期高血压疾病 脑胎盘率 抑制素-A 胎儿生长受限 预测效能
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基于注意力机制增强的YOLOv8模型在采摘机器人抓取中的应用研究
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作者 黄友鹏 《国外电子测量技术》 2026年第1期236-241,共6页
针对采摘机器人在复杂环境中抓取精度低、易受干扰的问题,提出一种基于注意力机制增强YOLOv8模型的精确抓取方法。通过在YOLOv8中嵌入挤压-激励(Squeeze-and-Excitation,SE)与高效通道注意力(Efficient Channel Attention,ECA)机制,构... 针对采摘机器人在复杂环境中抓取精度低、易受干扰的问题,提出一种基于注意力机制增强YOLOv8模型的精确抓取方法。通过在YOLOv8中嵌入挤压-激励(Squeeze-and-Excitation,SE)与高效通道注意力(Efficient Channel Attention,ECA)机制,构建融合注意力机制的轻量化检测模型,以提升果实目标的识别准确率与鲁棒性。结合RGB-D相机获取的深度信息,将检测结果转换为相机坐标系下的目标位姿,并经坐标变换得到机器人坐标系中的抓取位姿,最终通过运动规划实现机械臂的精准抓取。在采摘场景下的实验表明,本文方法抓取成功率在0.95以上,且路径规划准确、稳定性好。该方法验证了所提模型与抓取策略的有效性,为采摘机器人的实际应用提供了可靠的技术支持。 展开更多
关键词 挤压-激励注意力机制 高效通道注意力机制 轻量化 YOLOv8检测模型 采摘机器人 精确抓取
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Body composition and compensatory growth in Nile tilapia Oreochromis niloticus under different feeding intervals 被引量:1
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作者 高阳 王子威 +1 位作者 HUR Jun-wook LEE Jeong-Yeol 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第4期945-956,共12页
We investigated the growth and body composition of Nile tilapia under five different feeding regimes. A control group was fed to satiation twice daily for 185 days; four treatment groups were fed at intervals of 2, 3,... We investigated the growth and body composition of Nile tilapia under five different feeding regimes. A control group was fed to satiation twice daily for 185 days; four treatment groups were fed at intervals of 2, 3, 4 or 7 days(dietary ‘restricted' period, days 0–80) and then fed to satiation(‘refeeding' period, days 80–185). Compensatory growth in weight and length of the feed-restricted groups was observed during the refeeding period. However, the growth of none of the restricted groups caught up with that of the control group over the experimental period. Feed intake upon refeeding increased with the duration of deprivation. There were no significant differences in feed efficiency between the restricted and control groups during the refeeding stage, suggesting that hyperphagia was the mechanism responsible for the increased growth rates during this period. Tilapia preferentially used n-3 polyunsaturated fatty acids and nonessential amino acids during the restricted-feeding period. Higher production was achieved by higher feed consumption. We suggest that if attainment of market size in minimum time is required, fish should be consistently fed to satiation, while taking care to avoid the possible negative consequences of overfeeding. 展开更多
关键词 restricted feeding HYPERPHAGIA feed efficiency fatty acid amino acid TILAPIA
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国家审计信息化建设与区域绿色创新 被引量:2
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作者 李晓慧 宝露日 《南京审计大学学报》 北大核心 2025年第4期12-21,共10页
国家审计信息化建设助力国家治理监督体系建设,不仅在事后系统化纠正偏误,更能够利用动态审计提升国家审计的预防机制效能,从根本上优化地方政府政策制度的制定和实施,有助于区域绿色创新。因此,基于我国2016—2021年省级面板数据,利用S... 国家审计信息化建设助力国家治理监督体系建设,不仅在事后系统化纠正偏误,更能够利用动态审计提升国家审计的预防机制效能,从根本上优化地方政府政策制度的制定和实施,有助于区域绿色创新。因此,基于我国2016—2021年省级面板数据,利用SBM-DEA模型构建区域绿色创新指标,探索了国家审计信息化建设对区域绿色创新的影响及其内在机制。研究发现,国家审计信息化建设显著提升了区域绿色创新;机制分析发现,国家审计信息化建设主要通过提升地方政府财政支出效率、优化地区产业结构两条路径来促进区域绿色创新;异质性分析表明,该作用在数字经济发展程度、法治水平、教育水平较高地区更加显著。研究有助于厘清“国家宏观治理—地方政府行为—区域绿色创新”这一从宏观治理到微观经济的作用路径,对地方政府基于国家审计视角探索区域绿色发展政策具有重要借鉴作用。 展开更多
关键词 国家审计信息化建设 地方政府行为 区域绿色创新 监督效应 激励效应 财政支出效率 产业结构优化
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创新政策组合对企业研发效率的影响研究——基于财税政策视角
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作者 梁彤缨 喻守鹏 《中国科技论坛》 北大核心 2025年第9期61-69,共9页
本文基于财税政策的视角考察了“创新政策工具组合”和“创新政策层级组合”对企业研发效率的影响。采用2008—2019年中国创业板和中小板上市公司作为研究样本,运用数据包络分析法测算企业研发效率,并运用逆概率加权回归调整法估计创新... 本文基于财税政策的视角考察了“创新政策工具组合”和“创新政策层级组合”对企业研发效率的影响。采用2008—2019年中国创业板和中小板上市公司作为研究样本,运用数据包络分析法测算企业研发效率,并运用逆概率加权回归调整法估计创新政策组合的效果。主要研究结论如下:创新政策工具组合、创新政策层级组合对于企业研发效率的影响显著为正,政策“组合拳”具备良好的互补作用和协同效应;分别与单一政策工具、单一层级政策相比,创新政策工具组合、创新政策层级组合的强大合力对于企业研发效率的促进作用更为突出并且更加稳定;与弱融资约束企业相比,创新政策工具组合对强融资约束企业研发效率的正向影响更大;与国有企业相比,创新政策工具组合、创新政策层级组合对非国有企业研发效率的正向影响均更大。 展开更多
关键词 企业研发效率 创新政策组合 研发补贴 税收优惠
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