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Upper bound stability analysis of tiered geosynthetic-reinforced soil wall
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作者 Chengzhi Xiao Xiangsheng Meng +1 位作者 Shan Gao Luqiang Ding 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第1期556-572,共17页
The tiered geosynthetic-reinforced soil (GRS) walls have been increasingly applied in the high and steep retaining soil structures. However, very little is known about the design method for the tiered GRS wall in prac... The tiered geosynthetic-reinforced soil (GRS) walls have been increasingly applied in the high and steep retaining soil structures. However, very little is known about the design method for the tiered GRS wall in practice. This study is aimed at proposing an upper-bound stability analysis method of a tiered GRS wall. The proposed method was firstly validated by the existing results from the centrifuge test and the numerical method, and then a parametric study was performed to investigate the effects of the cohesionless backfill friction angle φ1 and the wall geometric parameters including the offset distance, the total wall height, the batter angle δ, the number of tiers n, and wall height ratio of adjacent tiers on the dimensionless equivalent earth pressure coefficient KT. The analysis results demonstrated that as the φ1 increases, the shear strength of backfill is enhanced and thus the KT or the total reinforcement tensile force decreases, and the KT decreases with the increase of the offset distance at the initial stage and then becomes stable when it reaches a certain critical value. For a fixed offset distance, the KT or the total reinforcement tensile force decreases with the increase of the δ. For the two-tiered GRS walls having the offset distance less than the critical value, the wall with the smaller wall height ratio has a larger KT. Further, the variation of the location of the critical failure surfaces of tiered GRS walls was presented in this study with the variation of the φ1 and the wall geometry. 展开更多
关键词 GEOSYNTHETICS tiered GRS walls Offset distance Upper bound theorem Internal stability
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Debates on the Tiered Electricity Pricing Mechanism in China
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作者 Lin Boqiang 《Electricity》 2011年第3期7-11,共5页
Based on the Ramsey theory-the foundation for the tiered electricity pricing mechanism, this article analyzes the effects of the tiered electricity pricing system on social justice, eff iciency and commodity prices, a... Based on the Ramsey theory-the foundation for the tiered electricity pricing mechanism, this article analyzes the effects of the tiered electricity pricing system on social justice, eff iciency and commodity prices, and concludes that the system would direct subsidies to flow into low income groups, and promote energy conservation and emissions reduction by restricting over-consumption of high income groups, without enormous effect on commodity prices. The key to designing the tiered system is how to estimate the amount of electricity use for each tier, so as to avoid excluding low income groups from the subsidy or including high income groups in the subsidy. 展开更多
关键词 reform on electricity pricing system tiered electricity pricing electricity price for residents
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Equity-Efficiency Trade-offs in Healthcare System Reform:The Perspective of Tiered Diagnosis and Treatment in China
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作者 Daisheng Tang Zhen Zhang +2 位作者 Xinyuan Wang Tao Bu Qiushi Feng 《China & World Economy》 2025年第3期150-196,共47页
Eforts to reform healthcare systems globally have long been driven by the inherent tradeofs between equity and eficiency.Using a patient referral model,we constructed a costbenefit matrix for both hospitals and patien... Eforts to reform healthcare systems globally have long been driven by the inherent tradeofs between equity and eficiency.Using a patient referral model,we constructed a costbenefit matrix for both hospitals and patients.We analyzed the effects of nominal tiered diagnosis and treatment(TDT)using medical institutions'monthly report data from Sichuan province spanning 2012 to 2018.Additionally,we assessed the effects of actual TDT based on inpatient medical records data from Sichuan province spanning 2015 to 2018.We further discussed the potential for the TDT model to achieve Pareto improvements in addressing equity-eficiency trade-ofs in healthcare.Our findings suggest that nominal TDT failed to improve patients'medical behaviors.In contrast,actual TDT improved medical efficiency by enhancing patient outcomes and reducing the relative length of hospital stay,while also promoting medical equity by narrowing disparities in out-of-pocket expenses and health insurance reimbursements.Moreover,the effects of actual TDT on eficiency and equity varied across hospital types,disease categories,and inpatient populations.Actual TDT has the potential to generate Pareto improvements in managing the equity-eficiency trade-ofs within the healthcare system.Strengthening actual referral behaviors proved crucial for fully realizing the benefits of the TDT model. 展开更多
关键词 actual tiered diagnosis and treatment equity-efficiency trade-offs nominal tiered diagnosis and treatment Pareto improvement
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Synergistic strategies for pollution and carbon emission reduction in China's wastewater treatment:A comprehensive tiered assessment and benchmarking framework
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作者 Xiaoshu Hou Yuchen Deng +4 位作者 Lu Qin Xin Xie Yilan Sun Gang Yan Miao Li 《Eco-Environment & Health》 2025年第2期63-71,共9页
China's dual-carbon goals challenges wastewater treatment plants(WWTPs),requiring integrated pollution control and carbon emission reduction.Critical gaps hinder China's strategies for WWTPs,particularly in id... China's dual-carbon goals challenges wastewater treatment plants(WWTPs),requiring integrated pollution control and carbon emission reduction.Critical gaps hinder China's strategies for WWTPs,particularly in identifying upgrade needs,optimizing performance,and assessing the local benchmark plants as references.This study addresses these gaps through greenhouse gas(GHG)emission accounting and impact factor analysis,using monthly data from 2232 WWTPs across China.A tiered assessment methodology was developed to evaluate the synergy between pollution reduction and carbon mitigation,including indicators,methodologies,and assessment criteria.Results indicate that indirect emissions from electricity and chemical consumption accounted for 59.9%of total GHG emissions.Key factors influencing these indirect emissions included plant scale,treatment processes,geographic area,operational load,electricity consumption,and influent quality.Through the tiered assessment,WWTPs were classified into three categories:priority control(861 plants),general control(730 plants),and maintenance(641 plants).Furthermore,222 benchmark plants were identified as exhibiting optimal synergy between pollution control and carbon reduction.For 80%of the benchmark plants,the ranges for carbon emission intensity,influent COD,influent C/N ratio,electricity consumption intensity,and operating load were 0.258–0.482 kg CO2e/t,175–338 mg/L,6.13–10.9,0.149–0.260 kWh per tonne of influent,and 88.0%–110%,respectively.Achieving these benchmark standards across all WWTPs could lead to a 30%reduction in total GHG emissions.Finally,the study proposes targeted policies to enhance the synergy between pollution control and carbon reduction strategies in China's urban wastewater treatment systems. 展开更多
关键词 WWTPs Synergy reduction tiered assessment Benchmark plants Policy implications
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Tiers of Enduring Harmony China preserves agricultural heritage as a living testament to ancient wisdom that harmonizes people,nature,and sustainable development
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作者 Guo Xixian Jiao Meng 《China Report ASEAN》 2025年第10期18-21,共4页
In the terraced fields in Honghe Hani and Yi Autonomous Prefecture,southwest China’s Yunnan Province,the morning mist drifts up from the valleys while the tiered ridges spread like the fingerprints of the earth.
关键词 Yunnan Province tiered ridges tiers terraced fields enduring harmony agricultural heritage Honghe Hani Yi Autonomous Prefecture sustainable development
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More Than Meets the Eye How the Honghe Hani Rice Terraces inspire a sustainable future
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作者 Guo Xixian Feng Jiahan 《China Report ASEAN》 2025年第10期26-28,共3页
French photographer Yann Layma first captured a moment at the Honghe Hani Rice Terraces in 1993.The tiered fields climbed like stairways into the sky.Glints of water appeared and disappeared through drifting clouds.Ha... French photographer Yann Layma first captured a moment at the Honghe Hani Rice Terraces in 1993.The tiered fields climbed like stairways into the sky.Glints of water appeared and disappeared through drifting clouds.Hani farmers could be seen quietly tending the land.Deeply moved,Layma spent six months producing Mountain Sculptors-a collection that included a film,a photo album,a travel diary,and nearly 10,000 photographs. 展开更多
关键词 Yann Layma tiered fields Hani farmers film Honghe Hani Rice Terraces sustainable future mountain sculptors French photographer
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Global invasive alien plant management lists:Assessing current practices and adapting to new demands
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作者 Fei-Fei Li Qiang Hao +3 位作者 Xia Cui Ruo-Zhu Lin Bin-Sheng Luo Jin-Shuang Ma 《Plant Diversity》 2025年第4期666-680,共15页
Invasive alien species(IAS)significantly threaten global biodiversity and ecosystem stability.Despite increasing management efforts,a critical knowledge gap existed in understanding commonalities and disparities among... Invasive alien species(IAS)significantly threaten global biodiversity and ecosystem stability.Despite increasing management efforts,a critical knowledge gap existed in understanding commonalities and disparities among national strategies.We analyzed several IAS management lists from 23 countries and the European Union,focusing specifically on vascular plant species within these lists.List composition,characteristics,and associated management measures were analyzed.Key patterns in species prioritization across national lists and intercontinental exchange of invasive alien plants(IAPs)were identified.Pistia stratiotes,Pontederia crassipes,Salvinia molesta,Cabomba caroliniana,Ulex europaeus were identified as globally recognized threats,being listed by at least 33.3%of analyzed countries and invading five or more continents.Aquatic plants were found to be more frequently included in management lists.A significant directional invasion pattern between the Eastern and Western Hemispheres was identified.Species native to Asia were observed to dominate as significant donors of IAPs across continents.The analysis of list management strategies highlighted substantial gaps in achieving Target 6 of the Kunming-Montreal Global Biodiversity Framework,particularly in species prioritization and inclusion of potential IAPs.In response to these challenges,a tiered classification system for invasive alien species list was proposed,encompassing High-Priority,Watchlist,Potential,and Priority Site categories,which aimed at enhancing management effectiveness by tailoring strategies to different invasion stages and ecological contexts.This study could contribute to understanding global IAPs management strategies and serve as a reference for policymakers and conservation managers to identify priority IAPs and refine management approaches. 展开更多
关键词 Invasive alien plants Kunming-Montreal global biodiversity FRAMEWORK Global management strategies tiered classification system Biodiversity conservation
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Optimization of Supply and Demand Balancing in Park-Level Energy Systems Considering Comprehensive Utilization of Hydrogen under P2G-CCS Coupling
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作者 Zhiyuan Zhang Yongjun Wu +4 位作者 Xiqin Li Minghui Song Guangwu Zhang Ziren Wang Wei Li 《Energy Engineering》 2025年第5期1919-1948,共30页
The park-level integrated energy system(PIES)is essential for achieving carbon neutrality by managing multi-energy supply and demand while enhancing renewable energy integration.However,current carbon trading mechanis... The park-level integrated energy system(PIES)is essential for achieving carbon neutrality by managing multi-energy supply and demand while enhancing renewable energy integration.However,current carbon trading mechanisms lack sufficient incentives for emission reductions,and traditional optimization algorithms often face challenges with convergence and local optima in complex PIES scheduling.To address these issues,this paper introduces a low-carbon dispatch strategy that combines a reward-penalty tiered carbon trading model with P2G-CCS integration,hydrogen utilization,and the Secretary Bird Optimization Algorithm(SBOA).Key innovations include:(1)A dynamic reward-penalty carbon trading mechanism with coefficients(μ=0.2,λ=0.15),which reduces carbon trading costs by 47.2%(from$694.06 to$366.32)compared to traditional tiered models,incentivizing voluntary emission reductions.(2)The integration of P2G-CCS coupling,which lowers natural gas consumption by 41.9%(from$4117.20 to$2389.23)and enhances CO_(2) recycling efficiency,addressing the limitations of standalone P2G or CCS technologies.(3)TheSBOA algorithm,which outperforms traditionalmethods(e.g.,PSO,GWO)in convergence speed and global search capability,avoiding local optima and achieving 24.39%faster convergence on CEC2005 benchmark functions.(4)A four-energy PIES framework incorporating electricity,heat,gas,and hydrogen,where hydrogen fuel cells and CHP systems improve demand response flexibility,reducing gas-related emissions by 42.1%and generating$13.14 in demand response revenue.Case studies across five scenarios demonstrate the strategy’s effectiveness:total operational costs decrease by 14.7%(from$7354.64 to$6272.59),carbon emissions drop by 49.9%(from 5294.94 to 2653.39kg),andrenewable energyutilizationincreases by24.39%(from4.82%to8.17%).These results affirmthemodel’s ability to reconcile economic and environmental goals,providing a scalable approach for low-carbon transitions in industrial parks. 展开更多
关键词 Park-level integrated energy system P2G-CCS coupling comprehensive utilization of hydrogen rewardpenalty tiered carbon trading mechanism secretary bird optimization algorithm
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AI standardization in Europe
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作者 Sebastian Hallensleben 《China Standardization》 2025年第5期23-23,共1页
If you look into the EU AI Act,you will find that the requirements are specified at a very high level.This is because the details are defined elsewhere.That is what standardization is doing.If we look at the world of ... If you look into the EU AI Act,you will find that the requirements are specified at a very high level.This is because the details are defined elsewhere.That is what standardization is doing.If we look at the world of AI standardization,there are three tiers-the international tier,the European tier and the national tier.There are also AI standardization committees at all three levels. 展开更多
关键词 EU AI Act AI standardization committees ai standardization international tier national tier AI standardization European tier
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观赛数据的背后,反映核心观众和地区效应
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作者 张牧之 《电子竞技》 2025年第7期56-57,共2页
从北京时间3月16日下午到3月17日凌晨,英雄联盟、DOTA2和CS2三个最头部的端游项目,先后进行了各自Tier1级别的赛事决赛。尽管比赛是在同一天进行,但三场决赛的开赛时间却完美错开了。英雄联盟先锋赛的决赛在下午四点开打,持续了三个半... 从北京时间3月16日下午到3月17日凌晨,英雄联盟、DOTA2和CS2三个最头部的端游项目,先后进行了各自Tier1级别的赛事决赛。尽管比赛是在同一天进行,但三场决赛的开赛时间却完美错开了。英雄联盟先锋赛的决赛在下午四点开打,持续了三个半小时。DOTA2的PGL瓦拉几亚S3决赛则于16日晚9点开始,在刚过0点后结束。紧接着CS2的EPL S21在17日零点开赛,历经五小时鏖战决出冠军。 展开更多
关键词 观赛数据 Tier1赛事 英雄联盟 DOTA2 核心观众 CS2
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A study on abortion care services in different tiers of rural health care in Malda district of West Bengal, India
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作者 Debjani Sengupta Pramit Ghosh 《Asian pacific Journal of Reproduction》 2025年第2期62-68,共7页
Objective:To assess comprehensive abortion care(CAC)services uptake and barriers to it in selected representative units of the three tier health care in the district of Malda in West Bengal,India.Methods:We conducted ... Objective:To assess comprehensive abortion care(CAC)services uptake and barriers to it in selected representative units of the three tier health care in the district of Malda in West Bengal,India.Methods:We conducted community-based,concurrent,parallel mixed methods study.Quantitative assessment of knowledge of primary health care workers on CAC and appropriate infrastructure assessment was done.Qualitative methods were used to identify themes affecting uptake of quality care among stakeholders.Results:A total of 48 staff nurses and 133 auxiliary nurses and midwives were included in the study.About half of nurses(of total 48)who were second tier health care provider and two thirds(of total 133)of first tier health care provider had incorrect knowledge about legality of abortion.Only 40%mothers seeking abortion were accompanied to subcentre by primary health care worker.At the third tier health care site,physicians insisted on necessity of refresher training.Suboptimal uptake of available CAC services was due to lack of enabling environment.Lack of updated training across health care workers was observed.Conclusions:Health care providers at the community level were unaware of facilities available for mothers seeking abortion.Higher level health care providers were unsure of specific knowledge about legal permissibility and sterilization of apparatus for abortion.At the highest level,more training on medical methods of abortion was required.The problems identified are amenable to correction,and some administrative and service-related provision on appropriate measures may lead to immediate success. 展开更多
关键词 Abortion care uptake Tiers of service primary health care PERCEPTION Service uptake
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Distributed Cooperative Regulation for Networked Re-Entrant Manufacturing Systems
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作者 Chenguang Liu Qing Gao +1 位作者 Wei Wang Jinhu Lü 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期636-638,共3页
Dear Editor,This letter focuses on the distributed cooperative regulation problem for a class of networked re-entrant manufacturing systems(RMSs).The networked system is structured with a three-tier architecture:the p... Dear Editor,This letter focuses on the distributed cooperative regulation problem for a class of networked re-entrant manufacturing systems(RMSs).The networked system is structured with a three-tier architecture:the production line,the manufacturing layer and the workshop layer.The dynamics of re-entrant production lines are governed by hyperbolic partial differential equations(PDEs)based on the law of mass conservation. 展开更多
关键词 production line networked re entrant manufacturing systems three tier architecture production linethe distributed cooperative regulation hyperbolic partial differential equations pdes based distributed cooperative regulation problem manufacturing layer
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Is Tiered Pricing For Electricity a Good Idea?
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《Beijing Review》 2012年第22期46-47,共2页
The National Development and Reform Commission of China (NDRC) came up with a draft for tiered pricing of household electric- it)' in March. After nationwide hearings, the new pricing policy will be carried out fr... The National Development and Reform Commission of China (NDRC) came up with a draft for tiered pricing of household electric- it)' in March. After nationwide hearings, the new pricing policy will be carried out from June. It also sparks heated debate on whether tiered pricing of household electricity is ap- propriate in China currently. The following are excerpts of some opinions on media. 展开更多
关键词 Is tiered Pricing For Electricity a Good Idea
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弗朗索瓦·邦的数字写作及其启示——以Le Tiers Livre网站为例
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作者 曹丹红 《语言与文化论坛》 2024年第1期71-81,共11页
弗朗索瓦·邦是较早利用网络技术进行数字实践与数字写作的法国当代作家。他在自创的Le Tiers Livre网站进行了形式多样的数字写作:添加对作品的总体评论;通过超链接形式在不同作品之间建立联系;续写;纸质版与网络版作品互为补充;... 弗朗索瓦·邦是较早利用网络技术进行数字实践与数字写作的法国当代作家。他在自创的Le Tiers Livre网站进行了形式多样的数字写作:添加对作品的总体评论;通过超链接形式在不同作品之间建立联系;续写;纸质版与网络版作品互为补充;通过添加对作品整体与局部的详细评论变旧书为新作;等等。通过不断评论、修改、续写、利用自己的旧文本,邦在旧作品的基础上获得了全新的作品,实现了文学创作形式的更新,同时也推动人们在技术时代对文学创作与观念进行更为深入的反思。 展开更多
关键词 弗朗索瓦·邦数字写作 Le Tiers Livre
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不同模拟方法对稻麦轮作系统温室气体估算差异 被引量:1
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作者 杨雨茗 《江苏农业科学》 北大核心 2024年第7期231-240,共10页
温室气体排放导致的全球气候变化问题是社会关注的重要问题,如何较准确地估算各领域内的温室气体排放通量对制定减排策略具有重要意义。为分析研究区水稻—冬小麦轮作系统温室气体(CH_(4)、N_(2)O)排放水平,对比IPCC2006 Tier2及DNDC模... 温室气体排放导致的全球气候变化问题是社会关注的重要问题,如何较准确地估算各领域内的温室气体排放通量对制定减排策略具有重要意义。为分析研究区水稻—冬小麦轮作系统温室气体(CH_(4)、N_(2)O)排放水平,对比IPCC2006 Tier2及DNDC模型法估算研究区稻麦轮作系统的CH_(4)和N_(2)O排放通量估算差异,定量评估DNDC模型是否适用于轮作系统的温室气体排放估算。于2015—2018年进行稻麦轮作野外试验,利用静态箱-气相色谱分析法定期测定CH_(4)和N_(2)O排放通量,结合田间管理和气象数据开展IPCC2006 Tier2和DNDC模型模拟,利用DNDC模型模拟轮作和非轮作情景的稻麦温室气体排放通量。结果表明,DNDC模型可以较好地模拟出稻田CH_(4)、N_(2)O和麦田N_(2)O排放通量时序变化特征,估算误差分别为-4.8%、-11.6%、-10.8%,精度优于IPCC2006 Tier2;DNDC模型对稻麦轮作的GWP模拟精度高于IPCC2006 Tier2,稻田和麦田GWP模拟相对误差分别为-5.9%、-21.7%;除了冬小麦生育期CH_(4)排放通量,DNDC轮作模式对其他稻麦轮作温室气体排放通量的模拟相对误差均低于非轮作模式。进而为区域农业温室气体估算及制定减排方案提供科学依据。 展开更多
关键词 稻麦轮作 DNDC模型 IPCC2006 Tier2 温室气体
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中国农田管理土壤碳汇估算 被引量:116
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作者 金琳 李玉娥 +4 位作者 高清竹 刘运通 万运帆 秦晓波 石锋 《中国农业科学》 CAS CSCD 北大核心 2008年第3期734-743,共10页
【目的】长期大规模翻耕和秸秆燃烧造成土壤有机质(SOM)大量损失,使农田成为温室气体的一个排放源。然而,近年来,随着免耕技术的逐步推广、秸秆还田面积的增加,加上施肥、灌溉等农田管理措施的应用,农田土壤有机碳(SOC)储量有所回升,预... 【目的】长期大规模翻耕和秸秆燃烧造成土壤有机质(SOM)大量损失,使农田成为温室气体的一个排放源。然而,近年来,随着免耕技术的逐步推广、秸秆还田面积的增加,加上施肥、灌溉等农田管理措施的应用,农田土壤有机碳(SOC)储量有所回升,预计其将成为温室气体的吸收汇。本文通过分析各种农田管理措施下土壤有机碳(SOC)的变化量,估算中国农田管理土壤碳汇量,为制定中国农田温室气体清单提供科学参考。【方法】通过查阅相关文献著作等,构建农田管理情景,分析各管理措施长期定位试验土壤有机碳变化量的数据。根据中国农作制的分区,估算各区域及水田、旱地农田管理下的碳汇量,并与政府间气候变化专门委员会(IPCC)制定的2006IPCC国家温室气体排放清单指南中农田仍为农田的层次(Tier)2方法的估算结果进行比较。最后用Meta分析法估算中国农田管理土壤碳汇量。【结果】不同农田管理措施对土壤碳的影响不同。各种措施表现为化肥与有机肥配施的增碳作用最大,达到0.889tC·ha-1·a-1;其次为秸秆还田、施有机肥和免耕,分别为0.597、0.545、0.514tC·ha-1·a-1;施化肥的作用最不明显,仅为0.129tC·ha-1·a-1。这一结果明显高于IPCCTier2方法估算的结果。研究还揭示,不同管理措施在不同区域对土壤有机碳变化的影响存在一定的差异,黄淮海区、长江上中游区和西南区增加量较大,东北区增加量较小,在施化肥条件下东北黑土SOC甚至有降低的趋势。土壤有机碳的年增长率和初始值之间呈很好的负相关,由此可得出不同管理措施下农田土壤有机碳的平衡值及固碳潜力。【结论】农田管理措施中,配施、秸秆还田、施有机肥和免耕可以在很大程度上提高土壤SOC含量。其中,配施和秸秆还田的固碳潜力较大。 展开更多
关键词 中国 农田管理 土壤碳汇 IPCC Tier2 META分析
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基于IPCC Tier 1层级的中国反刍家畜胃肠道甲烷排放格局变化分析 被引量:9
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作者 王荣 邓近平 +4 位作者 王敏 王玉诗 张玉茹 颜志成 谭支良 《生态学报》 CAS CSCD 北大核心 2015年第21期7244-7254,共11页
依据政府间气候变化委员会(IPCC)2006年公布的反刍家畜胃肠道CH4排放系数(奶牛61 kg CH4头-1a-1,肉役牛47 kg CH4头-1a-1,绵羊和山羊均为5 kg CH4头-1a-1)和IPCC Tier 1计算方法,结合《中国统计年鉴》和《中国畜牧业统计年鉴》,估算了... 依据政府间气候变化委员会(IPCC)2006年公布的反刍家畜胃肠道CH4排放系数(奶牛61 kg CH4头-1a-1,肉役牛47 kg CH4头-1a-1,绵羊和山羊均为5 kg CH4头-1a-1)和IPCC Tier 1计算方法,结合《中国统计年鉴》和《中国畜牧业统计年鉴》,估算了中国以及各个省份1990—2010年CH4的排放总量,绘制出中国反刍家畜胃肠道CH4排放格局及历史变化图。研究结果表明:11990—2010年期间,中国反刍家畜胃肠道CH4排放量(5.90—7.65 Tg)总体呈现先上升(1995年最高)后下降的趋势,其中肉役牛(主要是黄牛和水牛)胃肠道CH4排放量(>4.33 Tg)及其所占比例(>65%)最大。奶牛胃肠道CH4排放量及其比例呈现逐年增加的趋势,2006年(0.83 Tg,12.7%)超过山羊和绵羊胃肠道CH4排放量及其比例,成为中国反刍家畜胃肠道CH4排放第二大源。但是,奶牛单位产奶量所排放的CH4量逐年降低,表明中国奶牛饲养技术与生产性能不断提高。2中国反刍家畜胃肠道CH4排放格局呈现区域集中特点,主要集中在中西部和北部的各个省份,其中四川、内蒙古、新疆、河南、西藏、山东、河北、黑龙江、云南和甘肃等10个省份的排放量占中国排放总量的50%以上。总之,1990—2010年间,中国反刍家畜胃肠道CH4排放总量为(6.77±0.46)Tg(肉役牛为主要排放源),随时间推移呈现先上升后下降的趋势;中国反刍家畜胃肠道CH4排放的格局呈区域集中分布,中西部和北部的各个省份占60%以上。 展开更多
关键词 反刍家畜 IPCC Tier 1 甲烷排放
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“深海一号”载人潜水器支持母船设计关键技术 被引量:1
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作者 张勇 周宁 +3 位作者 张福民 丁忠军 胡震 田赤英 《船舶工程》 CSCD 北大核心 2021年第3期48-55,共8页
"深海一号"是中国第一艘为"蛟龙"号业务化运营提供支持保障的载人潜水器支持母船。文章从船型优化、支持保障能力及功能兼容性、电力推进系统谐波抑制、环境友好、水下辐射噪声、适居性等方面对该船在设计中面临的... "深海一号"是中国第一艘为"蛟龙"号业务化运营提供支持保障的载人潜水器支持母船。文章从船型优化、支持保障能力及功能兼容性、电力推进系统谐波抑制、环境友好、水下辐射噪声、适居性等方面对该船在设计中面临的主要挑战及其解决方案进行了分析说明,并与国内外同类船舶进行了对比。结果显示,"深海一号"的各项主要指标均优于国内外典型同类船舶。 展开更多
关键词 载人潜水器支持母船 斧型首专利线型 TierⅢ 振动噪声 水下噪声
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The Pathway of China’s Integrated Delivery System:Based on the Analysis of the Medical Consortium Policies 被引量:3
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作者 Huan GAO Xing-li DU +1 位作者 Jia-zhi LIAO Li XIANG 《Current Medical Science》 SCIE CAS 2022年第6期1164-1171,共8页
With the deepening of China’s health-care reform,an integrated delivery system has gradually emerged with the function of improving the efficiency of the health-care delivery system.For China’s integrated delivery s... With the deepening of China’s health-care reform,an integrated delivery system has gradually emerged with the function of improving the efficiency of the health-care delivery system.For China’s integrated delivery system,a medical consortium plays an important role in integrating public hospitals and primary care facilities.The first medical consortium policy issued after the COVID-19 pandemic apparently placed hope on accelerating the implementation of a medical consortium and tiered health-care delivery system.This paper illustrates the possible future pathway of China’s medical consortium through retrospection of the 10-year process,changes of the series of policies,and characteristics of the policy issued in 2020.We considered that a fully integrated medical consortium would be a major phenomenon in China's medical industry,which would lead to the formation of a dualistic care pattern in China. 展开更多
关键词 health-care reform integrated delivery system medical consortium tiered health-care delivery system health policy
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L21/31型船用中速柴油机减小NO_x排放研究 被引量:1
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作者 肖民 陈慧 《江苏科技大学学报(自然科学版)》 CAS 2012年第5期477-481,共5页
采用数值模拟方法,利用KIVA-3V程序对L21/31船用中速柴油机在满足TierⅡ标准前提下的NOx排放、影响因素和影响规律进行研究,为满足TierⅢ标准,探讨了该机型燃用二甲醚(DME)时NOx生成情况.研究结果表明:该机型适当减小进气温度、降低负... 采用数值模拟方法,利用KIVA-3V程序对L21/31船用中速柴油机在满足TierⅡ标准前提下的NOx排放、影响因素和影响规律进行研究,为满足TierⅢ标准,探讨了该机型燃用二甲醚(DME)时NOx生成情况.研究结果表明:该机型适当减小进气温度、降低负荷、推迟喷油提前角、增大转速、增大进气延迟角均可使NOx排放量在IMO TierⅡ范围内减小,但均不可能达到IMO TierⅢ的标准;该机型换用DME时NOx的排放量仅为燃用柴油的44.19%,通过进一步改变参数,可使NOx排放量减小为原机的25.82%,已非常接近TierⅢ标准的要求. 展开更多
关键词 船用中速柴油机 NOx KIVA-3V TierⅢ 二甲醚
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