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Seasonality of the Heat Budget on the Ross Sea Continental Shelf in a Coupled Regional Ocean-Sea Ice-Ice Shelf Model 被引量:1
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作者 Jiabao ZENG Chengyan LIU +6 位作者 Zhaomin WANG Liangjun YAN Yang LIU Yue XIA Xi LIANG Xiang LI Wen XU 《Advances in Atmospheric Sciences》 2025年第12期2453-2470,I0011-I0024,共32页
The heat content(HC)of water masses on the Ross Sea continental shelf plays an important role in regulating the circulations and the basal melting of the Ross Ice Shelf(RIS).Yet,the evolution of the HC on the Ross Sea... The heat content(HC)of water masses on the Ross Sea continental shelf plays an important role in regulating the circulations and the basal melting of the Ross Ice Shelf(RIS).Yet,the evolution of the HC on the Ross Sea continental shelf is still not clear due to the sparsity of observations.By employing a coupled regional ocean-sea ice-ice shelf model for the Ross Sea,this study analyzes the heat budget of water masses over the continental shelf and in the RIS cavity.According to the topographic features and the HC density,the continental shelf region is divided into 17 subdomains.The heat budget of the middle layer for every subdomain is analyzed.In addition,the heat budget for the RIS cavity is assessed for the first time.Owing to Modified Circumpolar Deep Water intrusion,water masses over the eastern shelf are warmer than over the western shelf,with the coldest water identified in the southwestern inner shelf.The horizontal heat flux mainly provides heat to the continental shelf,while the atmospheric forcing tends to warm up the ocean during the ice-melting period and cool down the ocean during the ice-freezing period.The vertical heat flux is generally upward and transports heat from the deep layer to the upper layer.In the RIS cavity,the seasonal cycle of the HC is dominated by the horizontal flux across the RIS front rather than the basal thermal forcing of the RIS. 展开更多
关键词 Ross Sea Ross Ice Shelf continental shelf heat content heat budget regional model
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Budget Travel
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作者 HU WANYING CHIEDZA MAVIS CHAKAWANEI 《ChinAfrica》 2025年第6期60-61,共2页
The Double Take column looks at a single topic from an African and Chinese perspective.This month,we discuss the concept of travel with a small budget.The concept of Qiongyou-travelling on a tight budget-has gained si... The Double Take column looks at a single topic from an African and Chinese perspective.This month,we discuss the concept of travel with a small budget.The concept of Qiongyou-travelling on a tight budget-has gained significant traction among young travellers in China. 展开更多
关键词 young travellers budget travel qiongyou travelling tight budget
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Automatic Ad Optimization and Budget Estimation with Artificial Intelligence, Health Service
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作者 Murat Başal Ömer FarukŞarkbay 《Economics World》 2025年第2期113-131,共19页
With the developing and rapidly changing technology,marketing strategies have necessarily changed in order to meet the demands and needs of consumers.The inability of businesses to keep up with this changing system pu... With the developing and rapidly changing technology,marketing strategies have necessarily changed in order to meet the demands and needs of consumers.The inability of businesses to keep up with this changing system pushes them out of the process.In daily life,where consumption never ends,marketing strategies are also consumed very quickly.Although the name changes according to age,the main goal is always more profitability.Digitalization of sales and marketing has made shopping in virtual environments widespread.Most customer services are performed by chatbots.It is seen that these studies are also carried out in the field of health services.From Siri to augmented reality applications,they are in our lives.These intelligent systems date back to the 1970s.So,where are the artificial intelligence and intelligent robots that have taken their place in almost every sector,from health to defense,which has been the favorite of recent years?Although the answer to this question has only recently begun to be researched,it seems that it will be one of the most important issues in the near future.In this study,which seeks a definitive answer to this question,the place and future of artificial intelligence in marketing strategies are discussed.In addition to contributing to the academic world,the study is thought to be useful in artificial intelligence studies. 展开更多
关键词 artificial intelligence automated advertising OPTIMIZATION budget estimation
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Research on Customer Conflict Management of Budget Hotels
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作者 ZHOU Xu LIU Songbai 《Management Studies》 2025年第1期14-23,共10页
This paper applies conflict management theory to study customer conflicts in budget hotels.Utilizing investigations and data analysis from budget hotels in Guilin,Guangxi Province,China,it identifies the factors that ... This paper applies conflict management theory to study customer conflicts in budget hotels.Utilizing investigations and data analysis from budget hotels in Guilin,Guangxi Province,China,it identifies the factors that influence the formation of customer conflicts and describes the characteristics of each stage in the development process,as well as the dual role of the conflicts.The paper also presents strategies for managing the transition from non-confrontational to confrontational conflicts. 展开更多
关键词 conflict management non-confrontational conflict conflict management strategy budget hotels
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Correction:A Valuable and Low‑Budget Process Scheme of Equivalized 1 nm Technology Node Based on 2D Materials
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作者 Yang Shen Zhejia Zhang +6 位作者 Zhujun Yao Mengge Jin Jintian Gao Yuhan Zhao Wenzhong Bao Yabin Sun He Tian 《Nano-Micro Letters》 2025年第11期717-720,共4页
Correction to:Nano-Micro Letters(2025)17:191 https://doi.org/10.1007/s40820-025-01702-7 Following the publication of the original article[1],the authors reported an error in Fig.3(b),and the figure legend was reversed... Correction to:Nano-Micro Letters(2025)17:191 https://doi.org/10.1007/s40820-025-01702-7 Following the publication of the original article[1],the authors reported an error in Fig.3(b),and the figure legend was reversed.The correct Fig.3 has been provided in this orrection. 展开更多
关键词 equivalized nano micro letters process scheme D materials low budget figure legend error CORRECTION nm technology node
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How to Make AGI Execute Reasoning Tasks in a Time-budget-sensitive Manner?
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作者 Yingjin Xu Bojie Feng 《逻辑学研究》 2025年第6期62-87,共26页
An idealized artificial general intelligence(AGI)system is expected to be smart enough to balance competing needs for caution and urgency via the management of limited time resources.However,mainstream Large Language ... An idealized artificial general intelligence(AGI)system is expected to be smart enough to balance competing needs for caution and urgency via the management of limited time resources.However,mainstream Large Language Models(LLMs),due to its working principle requiring operating resources of a tremendous magnitude,cannot be sensitive to the limitation of time resources,hence,it cannot adjust its time-distributions vis-à-vis the combinations of different internal and external conditions.Hence,a new AGI approach to the time-management is needed.By integrating the psychological notion of Need-For-Closure(NFC)and Nagel’s(2008)intellectual invariantism as well as Stanley’s(2005)stake-based epistemology,we will present a unified and computable framework for time-management,namely,a framework intended to handle both the system’s own estimation of the complexity of the task and its perception of the degree of stakes triggered by the task.In addition,in ourmodel,the computable notion of“budget deficit”plays a pivotal role in explaining how the NFC-value is fine-tuned to guide epistemic shifts. 展开更多
关键词 intellectual invariantism stake based epistemology management limited time artificial general intelligence agi system budget deficit AGI time management large language models llms due
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基于财政收入视角的预算绩效管理改革
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作者 马蔡琛 白铂 《河北学刊》 北大核心 2026年第1期151-159,共9页
预算由财政收支两翼构成,各级政府的收支预算均需纳入绩效管理。健全财政收入预算绩效管理框架对于提升政府组织财政收入的能力,确保财政可持续性,进而促进经济高质量发展具有重要意义。财政收入预算绩效管理的全球演化历程呈现出目标... 预算由财政收支两翼构成,各级政府的收支预算均需纳入绩效管理。健全财政收入预算绩效管理框架对于提升政府组织财政收入的能力,确保财政可持续性,进而促进经济高质量发展具有重要意义。财政收入预算绩效管理的全球演化历程呈现出目标维度逐步拓展、评价形式以税务部门为主以及与支出侧改革存在时间差等特征。财政收入预算绩效管理具有政策性、多维性和系统性等特质。鉴于简单地复制支出侧绩效管理框架难以充分体现财政收入资金的内在复杂性和多样性,需要构建财政收入视角下的预算绩效管理框架。该框架旨在建立共性与个性、宏观与微观有机结合的评价体系,多维度统筹分析的评价指标,全过程、全覆盖的收入评价过程。 展开更多
关键词 财政收入 预算绩效管理 税收绩效 财政资源统筹 现代预算制度
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超强台风“摩羯”强度异常变化特征及成因
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作者 杨国杰 韩浦城 +3 位作者 程正泉 龚月婷 韦凯华 沙天阳 《气象》 北大核心 2026年第1期16-28,共13页
利用站点监测、探空、FY-4B卫星、多普勒天气雷达、ERA5再分析数据等资料,对2024年第11号超强台风“摩羯”的强度变化特征及其原因进行了分析。发现“摩羯”是1981年以来登陆我国最强的秋季台风,在南海维持超强台风级达64 h,是维持超强... 利用站点监测、探空、FY-4B卫星、多普勒天气雷达、ERA5再分析数据等资料,对2024年第11号超强台风“摩羯”的强度变化特征及其原因进行了分析。发现“摩羯”是1981年以来登陆我国最强的秋季台风,在南海维持超强台风级达64 h,是维持超强台风级最久的南海台风,出现了三次快速增强,其中一次达到极端快速增强,12 h、24 h增强幅度均是自1981年以来最大的南海台风。强盛西南季风为台风发展提供充足水汽,稳定的副热带高压和大陆气流将陆地上的对流不稳定气团输送至台风中心附近,加强了台风环流附近的大气位势不稳定,减弱的环境垂直风切变和良好的高层出流条件均有利于台风快速增强和维持高强度。南海北部海面温度超过30℃,较常年偏高1~2℃,向大气提供了大量的潜热通量。“摩羯”快速增强时台风范围内动能增长明显,动能制造项的迅速增大是动能增长的主要因子,动能垂直和水平输送对动能增长也有重要贡献。 展开更多
关键词 台风“摩羯” 超强台风 快速增强 南海 季风 副热带高压 动能收支
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差分隐私保护的拜占庭鲁棒联邦学习模型
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作者 赵建喆 范树勋 +1 位作者 雷裴根 张月婷 《小型微型计算机系统》 北大核心 2026年第1期201-214,共14页
拜占庭鲁棒联邦学习的目标是让服务提供者在存在有限数量恶意客户端的情况下,准确学习全局模型,他们通过对客户端提交的本地模型更新进行统计检验,排除那些异常的更新.但是,目前方法只要针对恶意用户所带来的安全性问题,而没有考虑可能... 拜占庭鲁棒联邦学习的目标是让服务提供者在存在有限数量恶意客户端的情况下,准确学习全局模型,他们通过对客户端提交的本地模型更新进行统计检验,排除那些异常的更新.但是,目前方法只要针对恶意用户所带来的安全性问题,而没有考虑可能存在的隐私问题,即窃取模型参数而进行的攻击类型.有的考虑了数据异构性,但是没有考虑由于系统异构性带来的效用下降问题.针对目前现有的隐私保护的联邦学习算法存在的问题,本文设计并实现了拜占庭鲁棒联邦学习算法(Byzantine Robust-Differentially Private Federated Learning,BR-DPFL),该算法创新性地引入了一种双层过滤机制:第1层过滤通过定义面向两种异构性(系统和数据)的效用函数,减少可能受到拜占庭攻击或其它干扰的数据影响;第2层过滤采用指数机制评估客户端的性能,并优先选择效用函数表现优异的客户端参与训练.此外,针对参数共享过程中的隐私问题,本文算法通过添加高斯噪声满足差分隐私保护,并且基于效用函数设计自适应的隐私预算分配方法,对于效用表现高于一定阈值的优质用户将隐私预算放大来减少噪声摄入,在保证隐私的同时提升算法的效用.综合实验结果表明,该算法在MNIST与CIFAR-10数据集上的准确率分别达到了96.6%和64.5%,在精度上优于现有的联邦学习算法. 展开更多
关键词 联邦学习 差分隐私保护 拜占庭鲁棒性 隐私预算分配 双重过滤机制
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大数据时代高校图书馆采购策略创新研究
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作者 王蕊 《南阳理工学院学报》 2026年第1期124-128,共5页
大数据时代,高校图书馆的内外态势发生了很大改变,传统的采购模式难以满足日益增长的教学科研和阅读需求。文章分析了高校图书馆在采购预算、渠道、内容、决策机制等方面的现状与主要问题,提出了利用大数据优化预算分配、分类精准采购... 大数据时代,高校图书馆的内外态势发生了很大改变,传统的采购模式难以满足日益增长的教学科研和阅读需求。文章分析了高校图书馆在采购预算、渠道、内容、决策机制等方面的现状与主要问题,提出了利用大数据优化预算分配、分类精准采购、创新决策机制等建议,以期使图书馆采购更加高效、科学,更好地为读者服务。 展开更多
关键词 大数据 图书馆 预算分配 采购策略
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Influence of Climate and Daylength on the Activity Budgets of Feral Goats (Capra hircus) on the Isle of Rum, Scotland 被引量:5
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作者 石建斌 Robin Dunbar +1 位作者 李迪强 肖文发 《Zoological Research》 CAS CSCD 北大核心 2006年第6期561-568,共8页
Daytime activity budgets of feral goats ( Capra hircus ) were studied in 1981, 1982 and 2000 on the Isle of Rum, northwest Scotland. This paper analyzes the influence of key weather variables (temperature and rainf... Daytime activity budgets of feral goats ( Capra hircus ) were studied in 1981, 1982 and 2000 on the Isle of Rum, northwest Scotland. This paper analyzes the influence of key weather variables (temperature and rainfall) and seasonal variations in daylength on daytime activity budgets. This study showed that the percentage of daytime spent in feeding by feral goats on Rum Island decreased with average monthly temperature, while the percentage of daytime spent in lying increased and rainfall had no significant effects on the percentage daytime spent in feeding or lying. The daylength varied greatly from January to December with the longest daylength being in June and July, and the shortest one in December and January. The amount of daytime spent feeding decreased from summer to winter, although the percentage of daytime spent feeding increased greatly from summer to winter. The seasonal variations in daylength seem to be an important factor in constraining feral goats' activity, especially in the cold and wet winters when forage biomass and quality are both at their lowest level. We discuss the influence of such constraining effects on the forage intake of these goats and their winter survival rate, as well as its implication for population regulation of these goats. 展开更多
关键词 WEATHER Activity budget DAYLENGTH Feral goat Rum Island
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Evaluation of Forest Carbon Budget of Liaoning Province in Recent 50 Years 被引量:1
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作者 王笑影 谢艳兵 +2 位作者 贾庆宇 吕国红 李荣平 《Meteorological and Environmental Research》 CAS 2010年第2期66-68,71,共4页
The interannual variation characteristics of NPP and carbon emission of Liaoning forest in recent 50 years (from 1961 to 2008) were analyzed based on the hydrothermal optimized NPP model and soil respiration Q10 model... The interannual variation characteristics of NPP and carbon emission of Liaoning forest in recent 50 years (from 1961 to 2008) were analyzed based on the hydrothermal optimized NPP model and soil respiration Q10 model.The results showed that the total amount of annual NPP was increased in recent 50 years,in which the amount of NPP (83.9 Mt) in 2008 was 2.8 times as high as that in 1961.Amount of NPP per unit area changed with different years,and the maximum value was 36.5% more than the minimum one.The net carbon budget of Liaoning forest was carbon sink,with annual 2.1 t CO2/hm2. 展开更多
关键词 FOREST Carbon budget Climate change China
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Diurnal activity rhythms and time budgets of captive Qinling golden takin(Budorcas taxicolor bedfordi) in the Qinling Mountains,Shaanxi,China 被引量:2
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作者 陈炜 申琦 +2 位作者 马清义 潘广林 雷初朝 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第2期149-152,共4页
In July 2006, the diurnal activity rhythms of 13 heads of captive Qinling golden takin were observed in Shaanxi Provincial Centre for the Breeding and Conservation of Rare Wildlife (SPCBCRW) at daylight (from 9:00... In July 2006, the diurnal activity rhythms of 13 heads of captive Qinling golden takin were observed in Shaanxi Provincial Centre for the Breeding and Conservation of Rare Wildlife (SPCBCRW) at daylight (from 9:00 am to 4:00 pm in July). The behavioral ethnogram was identified through observation at the sampling site, with the behaviors of golden takin recorded at 5 min interval using instantaneous scannable sampling method. The results indicated that the resting of golden takin took an important part in the daylight activities. Meanwhile, drinking and urinating and defecating were 1.92 and 0.54 and 0.92 times per head per day. Ambient temperature had a strong effect on the diurnal activity rhythms of golden takin. The diurnal activity rhymes were affected by ages of the animals effectively, which was expressed through differentiation of the time budgets. Moreover, different individuals in the same population showed some non-synchronously activity rhythms. 展开更多
关键词 CAPTIVITY Diurnal activity rhythm Golden takin Budorcas taxicolor bedfordi Time budget
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用Budget方法评估食品防腐剂摄入量 被引量:1
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作者 裴世春 张东杰 +1 位作者 程远 曹静晶 《粮油食品科技》 2006年第4期42-44,共3页
分析了在Codex为了设定食品添加剂的使用标准而被应用的Budget方法论,并提出了适用于中国人饮食情况的使用准则。在此基础上对苯甲酸及其钠盐、山梨酸及其钾盐、对羟基苯甲酸乙脂和双乙酸钠的国内理论最大摄入量进行了估算。其结果苯甲... 分析了在Codex为了设定食品添加剂的使用标准而被应用的Budget方法论,并提出了适用于中国人饮食情况的使用准则。在此基础上对苯甲酸及其钠盐、山梨酸及其钾盐、对羟基苯甲酸乙脂和双乙酸钠的国内理论最大摄入量进行了估算。其结果苯甲酸及其钠盐、对羟基苯甲酸乙脂、双乙酸钠的每日最大理论摄入量超过了ADI(acceptable daily intakes)值,而山梨酸及其钾盐的每日最大理论摄入量估算值低于ADI值,因此即使在允许使用的所有食品群里以目前使用标准使用山梨酸及其钾盐也不会造成危害。 展开更多
关键词 budget方法 食品防腐剂 风险评估 摄入量
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菲律宾蛤仔斑马蛤2号与未选育群体生理能量学对比研究
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作者 袁明军 蒋增杰 +4 位作者 姜娓娓 蔺凡 李伟伟 郝紫冰 张义涛 《渔业科学进展》 北大核心 2026年第1期60-69,共10页
为明确菲律宾蛤仔(Ruditapes philippinarum)斑马蛤2号与未选育群体在能量分配方面是否存在差异,解析新品种斑马蛤2号生长速度快的内在机理,于2023年7月,以大、中、小3种规格(壳长分别为40~45 mm、35~40 mm、30~35 mm)斑马蛤2号和未选... 为明确菲律宾蛤仔(Ruditapes philippinarum)斑马蛤2号与未选育群体在能量分配方面是否存在差异,解析新品种斑马蛤2号生长速度快的内在机理,于2023年7月,以大、中、小3种规格(壳长分别为40~45 mm、35~40 mm、30~35 mm)斑马蛤2号和未选育群体为实验对象,基于现场流水系统测定了摄食和代谢生理关键参数,对比分析了能量分配方式的不同。结果显示:3种规格斑马蛤2号的滤水率和同化效率均高于未选育群体,但差异不显著(P>0.05);中规格斑马蛤2号耗氧率显著高于未选育群体(P<0.05),而小规格斑马蛤2号耗氧率显著低于未选育群体(P<0.05);中、小规格斑马蛤2号排氨率均显著高于未选育群体(P<0.05);从能量摄入角度来看,大、中、小规格的斑马蛤2号摄食能较未选育群体均有一定程度的提升,分别提升了45.22%、18.60%和21.40%。从能量分配角度来看,大、中、小规格的斑马蛤2号吸收能较未选育群体分别提升了54.90%、18.60%、29.67%;大、中、小3种规格斑马蛤2号生长余力较未选育群体分别提升了57.65%、17.34%和31.79%。显示斑马蛤2号依靠较高的摄食能和略高的同化效率导致在能量分配中有更多能量用于生长,从而维持了较快的生长速度。研究结果为深化认识斑马蛤2号的生理学特征、进而服务新品种的养殖容量评估提供了基础数据。 展开更多
关键词 菲律宾蛤仔 斑马蛤2号 吸收效率 能量收支
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不同施磷量下石灰性褐土麦玉轮作周年产量、磷盈亏及土壤磷形态响应
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作者 杨慧敏 黄少辉 +7 位作者 杨军芳 王敬霞 聂浩亮 张静 杨文方 邢素丽 杨云马 贾良良 《植物营养与肥料学报》 北大核心 2026年第1期146-157,共12页
【目的】研究长期不同磷肥施用量对小麦-玉米轮作周年籽粒产量、土壤磷盈亏量的影响,阐明累积磷盈亏量与全磷、有效磷、不同形态磷和不同磷库的关系,为石灰性褐土磷肥高效利用提供理论支撑。【方法】本研究依托河北省石家庄市小麦-玉米... 【目的】研究长期不同磷肥施用量对小麦-玉米轮作周年籽粒产量、土壤磷盈亏量的影响,阐明累积磷盈亏量与全磷、有效磷、不同形态磷和不同磷库的关系,为石灰性褐土磷肥高效利用提供理论支撑。【方法】本研究依托河北省石家庄市小麦-玉米轮作化学磷肥施用长期定位试验,该试验始于2008年,其中不施磷处理始于2015年。选择5个施磷(P_(2)O_(5))水平:0、75、120、165、210 kg/hm^(2)(依次记为P0、P75、P120、P165、P210)。于2016—2022年,测定周年地上部产量、吸磷量和土壤磷盈亏量;2016、2019和2022年玉米收获后,采集各施磷处理小区0—20 cm表层土壤,利用Hedley法测定不同形态磷素含量,并分析土壤累积磷盈亏量与全磷、有效磷、磷活化系数、不同形态磷和不同磷库的响应特征。【结果】在石灰性褐土冬小麦-夏玉米轮作体系中,P120、P165、P210较P75处理周年籽粒产量和籽粒吸磷量分别显著增加9.54%和16.64%、11.81%和30.09%、12.46%和39.58%。以线性加平台模型拟合周年籽粒产量与施磷量间关系,周年稳产下的最优施磷量为P_(2)O_(5)112 kg/hm^(2)。P0、P75、P120、P165、P210处理年均磷盈亏量分别为-18.54、-0.84、13.22、27.93和43.91 kg/hm^(2),各处理间年均磷盈亏量差异显著。通过拟合施磷量与每年磷盈亏量的关系发现,施磷量超过76.64 kg/hm^(2)时土壤磷开始累积。土壤磷每盈余100 kg/hm^(2),土壤全磷、有效磷、活化系数分别提高29.70 mg/kg、3.88 mg/kg和0.31%;酸溶性无机磷(HCl-Pi)、碳酸氢钠无机磷(NaHCO_(3)-Pi)、氢氧化钠无机磷(NaOH-Pi)、水溶性磷(H_(2)O-Pi)、氢氧化钠有机磷(NaOH-Po)和碳酸氢钠有机磷(NaHCO_(3)-Po)含量分别提高20.90、4.09、1.53、0.57、0.53和0.44 mg/kg;活性磷、中活性磷和稳定性磷含量分别提高5.37、2.58和21.61 mg/kg;无机磷和有机磷含量分别提高26.96和1.03 mg/kg。土壤盈余磷素主要累积在表层,全磷累积量达盈余总量的77.22%。【结论】在石灰性褐土小麦-玉米轮作体系中,施磷超过76.64 kg/hm^(2)时土壤磷开始累积,土壤全磷、有效磷、磷活化系数和不同形态磷(除Residual-P外)含量随之提高,磷形态以HCl-Pi提高最明显;土壤磷库响应表现为稳定磷>活性磷>中活性磷,无机磷>有机磷。结合产量效应和环境风险,推荐合理的施磷量范围为112~135 kg/hm^(2),这既能满足周年稳产,又可将磷盈余控制在环境安全范围内。 展开更多
关键词 石灰性褐土 磷肥施用量 周年产量 磷盈亏 磷活化系数 磷形态
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无鱼粉饲料中添加Ala-Gln对施氏鲟幼鱼生长和能量代谢的影响
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作者 刘烊廷 王常安 +5 位作者 郭忠宝 王晗雅 王佳豪 陆绍霞 韩世成 刘红柏 《上海海洋大学学报》 北大核心 2026年第1期72-83,共12页
旨在探究无鱼粉饲料中添加不同水平二肽丙氨酰谷氨酰胺(Ala-Gln)后对施氏鲟(Acipenser schrenckii)幼鱼的生长性能、氨基酸代谢、能量收支的影响。将450尾初始体质量(21.66±1.02)g的施氏鲟幼鱼饲养在循环水养殖车间,随机分为5组(每... 旨在探究无鱼粉饲料中添加不同水平二肽丙氨酰谷氨酰胺(Ala-Gln)后对施氏鲟(Acipenser schrenckii)幼鱼的生长性能、氨基酸代谢、能量收支的影响。将450尾初始体质量(21.66±1.02)g的施氏鲟幼鱼饲养在循环水养殖车间,随机分为5组(每组3个重复,每个重复30尾)。对照组饲喂基础饲料,试验组饲喂分别添加0、0.25%、0.50%、0.75%、1.00%Ala-Gln的试验饲料,试验期56 d。结果表明:当饲料中添加0.50%~1.00%Ala-Gln时,其末重、肥满度显著高于对照组(P<0.05);饲料中添加0.25%~1.00%Ala-Gln后,施氏鲟生长能G和代谢能R与对照组相比有显著差异(P<0.05);饲料中添加0.75%Ala-Gln后,鱼体的半胱氨酸显著高于其他各组(P<0.05)。饲料中添加0.50%Ala-Gln后,鱼体的甘氨酸含量显著高于其他各组(P<0.05);摄食5 h后,血液中谷氨酰胺和丙氨酸含量显著升高(P<0.05)。饲料中添加0.50%Ala-Gln时,天门冬氨酸含量显著高于其他各组(P<0.05),对其主成分PLA分析表明,影响其血液代谢谱最主要的氨基酸为谷氨酰胺。综上所述,在无鱼粉饲料中添加0.75%~1.00%Ala-Gln可显著提高施氏鲟幼鱼生长性能,可能是因为Ala-Gln吸收后提高了机体谷氨酰胺的含量,从而影响机体代谢促进蛋白质合成。本研究可为Ala-Gln应用于植物蛋白饲料替代鱼粉对鲟鱼生长性能和相关代谢影响研究提供实际参考。 展开更多
关键词 无鱼粉 施氏鲟 Ala-Gln 生长 氨基酸代谢 能量收支
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咬齿牡蛎动态能量收支模型的参数获取及构建
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作者 马浩杰 张跃环 +4 位作者 王新萌 孟嵘钊 谭柳书仪 高天翔 张继红 《水产学报》 北大核心 2026年第1期156-168,共13页
【目的】构建咬齿牡蛎动态能量收支(DEB)模型,研究水温、叶绿素浓度对其生长的影响,为牡蛎礁的选址、设计及可持续管理提供理论支持。【方法】通过室内生理实验测定了DEB模型所需的参数。采用壳长与软体部湿重回归法计算形状系数δ_(m)... 【目的】构建咬齿牡蛎动态能量收支(DEB)模型,研究水温、叶绿素浓度对其生长的影响,为牡蛎礁的选址、设计及可持续管理提供理论支持。【方法】通过室内生理实验测定了DEB模型所需的参数。采用壳长与软体部湿重回归法计算形状系数δ_(m);根据不同温度条件下牡蛎的呼吸耗氧率,计算获得阿伦纽斯温度T_(A);经45 d的饥饿实验,获得形成单位体积结构物质所需的能量[E_(G)]、单位体积的最大存储能量[E_(M)]以及单位时间单位体积维持生命所需的能量[P·_(M)];摄食实验测定出最大摄食率{J·_(Xm)}和最大吸收率{P·_(Am)}等主要参数。通过对已有文献的数据挖掘和模型调试获取模型所需的其他参数。通过遥感技术方法获得2022年6月—2024年4月美济礁和大亚湾Chl.a浓度和水温,以此作为强制函数,利用R软件构建了大亚湾咬齿牡蛎的个体生长模型,对美济礁监测的咬齿牡蛎实际生长数据进行验证。【结果】通过室内实验成功测定了DEB模型所需的7个基本参数,其中δ_(m)为0.270,T_(A)为4900.01 K,[E_(G)]、[E_(M)]、[P·_(M)]分别为5600 J/cm^(3)、6382 J/cm^(3)、26 J/(cm^(3)·d),{P·_(Am)}和{J·_(Xm)}分别为244 J/(cm^(2)·d)和325 J/(cm^(2)·d)。模型模拟结果显示,软体部干重和壳长的模拟值与实测值呈显著线性关系。在美济礁和大亚湾海域中,咬齿牡蛎的生长受到Chl.a浓度和水温的双重限制,食物限制性强于水温。【结论】所构建的DEB模型能够很好地模拟咬齿牡蛎的个体生长情况,美济礁的温度与食物相较于大亚湾更适合咬齿牡蛎的生长。 展开更多
关键词 咬齿牡蛎 动态能量收支 模型参数 个体生长 美济礁
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Fund budget model for multipurpose transit smart card systems
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作者 张宁 钱振东 +1 位作者 陈恺 杨利强 《Journal of Southeast University(English Edition)》 EI CAS 2008年第1期95-98,共4页
The fund budget of multipurpose transit smart card systems is studied by stochastic programming to assign limited funds to different applications reasonably. Under the constraints of a gross fund, models of chance-con... The fund budget of multipurpose transit smart card systems is studied by stochastic programming to assign limited funds to different applications reasonably. Under the constraints of a gross fund, models of chance-constrained and dependentchance for the fund budget of multipurpose transit smart card systems are established with application scale and social demand as random variables, respectively aiming to maximize earnings and satisfy the service requirements the furthest; and the genetic algorithm based on stochastic simulation is adopted for model solution. The calculation results show that the fund budget differs greatly with different system objectives which can cause the systems to have distinct expansibilities, and the application scales of some applications may not satisfy user demands with limited funds. The analysis results indicate that the forecast of application scales and application future demands should be done first, and then the system objective is determined according to the system mission, which can help reduce the risks of fund budgets. 展开更多
关键词 multipurpose transit smart card systems fund budgeting stochastic programming genetic algorithm
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基于国际经验的紧密型县域医共体医保基金总额预算测算方案实证研究
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作者 李翔 张春峰 +1 位作者 李玲 刘丹 《中国卫生经济》 北大核心 2026年第2期19-25,共7页
目的:在推进紧密型县域医共体建设背景下,构建一套兼顾公平与激励的医保基金总额预算测算方案。方法:通过比较分析,优化由非协商因素和协商因素组成的测算框架;基于Y市医保结算与统计数据进行拟合并滚动预测。结果:多数年份各紧密型县... 目的:在推进紧密型县域医共体建设背景下,构建一套兼顾公平与激励的医保基金总额预算测算方案。方法:通过比较分析,优化由非协商因素和协商因素组成的测算框架;基于Y市医保结算与统计数据进行拟合并滚动预测。结果:多数年份各紧密型县域医共体医保基金预算拟合误差控制在5%以内。结论:采用非协商因素、协商因素、年度滚动校正的分层测算与决策框架,推进区域总额预算精细化改革,完善医疗机构质量绩效对接与结余激励,推动支付方式由“控费导向”向“控费+提质”协同转型。 展开更多
关键词 紧密型县域医共体 医保保障基金 总额预算 国际经验
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