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国内外森林健康评价指标体系综述

科技导报 2011年第33期29卷 72-79页

作者：沈剑波雷相东舒清态张会儒西南林业大学林学院昆明650224 中国林业科学研究院资源信息研究所北京100091

森林健康评价是当前国内外的热点问题,已成为国内外森林状况评估和森林资源管理的重要手段,但目前森林健康评价指标体系差别较大。对森林健康评价指标的种类和频度进行分析和讨论,发现国外森林健康评价指标主要集中于生态系统本身的属... 详细信息

森林健康评价是当前国内外的热点问题,已成为国内外森林状况评估和森林资源管理的重要手段,但目前森林健康评价指标体系差别较大。对森林健康评价指标的种类和频度进行分析和讨论,发现国外森林健康评价指标主要集中于生态系统本身的属性且相对稳定,国内评价指标则涵盖自然和社会经济等多个方面。与国外相比,国内森林健康指标过多、过泛,部分指标可操作性差,含义不清。需要制定统一和标准的森林健康评价指标,每个指标的阈值可因地域、经营目标、森林类型各异。

关键词：森林健康评价指标林分尺度景观/区域尺度

稀土元素在剪切带中的含量变异及变异机制──以胶南造山带北缘剪切带为例

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岩石矿物学杂志 1998年第1期17卷 17-22页

作者：周建波胡克申宁华高游孙加鹏长春科技大学地科系

剪切带内的构造岩在韧性变形前后其稀土元素的含量发生有规律的变异，表现在随变形程度的增强，各稀土元素的含量及ＬＲＥＥ、ＨＲＥＥ、ＲＥＥ总含量均明显增加，而稀土配分模式不变。通过胶南造山带花岗质构造岩变形前后的等比分析，... 详细信息

剪切带内的构造岩在韧性变形前后其稀土元素的含量发生有规律的变异，表现在随变形程度的增强，各稀土元素的含量及ＬＲＥＥ、ＨＲＥＥ、ＲＥＥ总含量均明显增加，而稀土配分模式不变。通过胶南造山带花岗质构造岩变形前后的等比分析，稀土元素的含量增加主要是由于构造岩变形之后较大的体积亏损所引起；并进一步根据含量变异与体积亏损之间的函数关系，求得花岗岩变形改造为糜棱岩的体积亏损率为１４．５％，改造为超糜棱岩的体积亏损率达２０％。

关键词：含量变异剪切带造山带变异机制稀土族

Remaining Life Prediction Method for Photovoltaic Modules Based on Two-Stage Wiener Process

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Energy Engineering 2025年第1期122卷 331-347页

作者： Jie Lin Hongchi shen Tingting Pei Yan Wu School of Electrical Engineering and Information Engineering Lanzhou University of TechnologyLanzhou730050China

Photovoltaic (PV) modules, as essential components of solar power generation systems, significantly influence unitpower generation *** service life of these modules directly affects these costs. Over time, the performanceof PV modules gradually declines due to internal degradation and external environmental *** cumulativedegradation impacts the overall reliability of photovoltaic power generation. This study addresses the complexdegradation process of PV modules by developing a two-stage Wiener process model. This approach accountsfor the distinct phases of degradation resulting from module aging and environmental influences. A powerdegradation model based on the two-stage Wiener process is constructed to describe individual differences inmodule degradation processes. To estimate the model parameters, a combination of the Expectation-Maximization(EM) algorithm and the Bayesian method is employed. Furthermore, the Schwarz Information Criterion (SIC) isutilized to identify critical change points in PV module degradation trajectories. To validate the universality andeffectiveness of the proposed method, a comparative analysis is conducted against other established life predictiontechniques for PV modules.

关键词： Photovoltaic modules degradation stochastic processes lifetime prediction

Optimizing Fine-Tuning in Quantized Language Models:An In-Depth Analysis of Key Variables

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Computers, Materials & Continua 2025年第1期82卷 307-325页

作者： Ao shen Zhiquan Lai Dongsheng Li Xiaoyu Hu National Key Laboratory of Parallel and Distributed Computing National University of Defense TechnologyChangsha410073China Strategic Assessments and Consultation Institute Academy of Military ScienceBeijing100091China

Large-scale Language Models(LLMs)have achieved significant breakthroughs in Natural Language Processing(NLP),driven by the pre-training and fine-tuning *** this approach allows models to specialize in specific tasks with reduced training costs,the substantial memory requirements during fine-tuning present a barrier to broader ***-Efficient Fine-Tuning(PEFT)techniques,such as Low-Rank Adaptation(LoRA),and parameter quantization methods have emerged as solutions to address these challenges by optimizing memory usage and computational *** these,QLoRA,which combines PEFT and quantization,has demonstrated notable success in reducing memory footprints during fine-tuning,prompting the development of various QLoRA *** these advancements,the quantitative impact of key variables on the fine-tuning performance of quantized LLMs remains *** study presents a comprehensive analysis of these key variables,focusing on their influence across different layer types and depths within LLM *** investigation uncovers several critical findings:(1)Larger layers,such as MLP layers,can maintain performance despite reductions in adapter rank,while smaller layers,like self-attention layers,aremore sensitive to such changes;(2)The effectiveness of balancing factors depends more on specific values rather than layer type or depth;(3)In quantization-aware fine-tuning,larger layers can effectively utilize smaller adapters,whereas smaller layers struggle to do *** insights suggest that layer type is a more significant determinant of fine-tuning success than layer depth when optimizing quantized ***,for the same discount of trainable parameters,reducing the trainable parameters in a larger layer is more effective in preserving fine-tuning accuracy than in a smaller *** study provides valuable guidance for more efficient fine-tuning strategies and opens avenues for further research into optimizing LLM

关键词： Large-scale Language Model Parameter-Efficient Fine-Tuning parameter quantization key variable trainable parameters experimental analysis

基于CART重要度排序和混合ELM模型的蒸散预测

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农业工程学报 2023年第14期39卷 89-96页

作者：师翊王应宽赵龙曹瑞雪王宇航沈剑波段震农业农村部规划设计研究院北京100125 河南科技大学农业装备工程学院洛阳471003 中国农业工程学会北京100125 北京市农林科学院信息技术研究中心北京100097

准确地预测区域蒸散有助于区域水资源的合理利用,减少水资源浪费。为从多项气象因子中筛选出核心因子,构建少因子蒸散预测模型,高效精确预测蒸散,该研究在九大农业区选取23个典型站点,搜集降水量、日照时数等8个气象因子数据,使用分类... 详细信息

准确地预测区域蒸散有助于区域水资源的合理利用,减少水资源浪费。为从多项气象因子中筛选出核心因子,构建少因子蒸散预测模型,高效精确预测蒸散,该研究在九大农业区选取23个典型站点,搜集降水量、日照时数等8个气象因子数据,使用分类回归树(classification and regression tree,CART)对气象因子进行重要度排序。基于排序结果,选取排序前3~5项气象因子,基于极限学习机(extreme learning machine,ELM)模型对蒸散进行预测。同时,使用遗传算法(genetic algorithm,GA),粒子群算法(particle swarm optimization,PSO),麻雀搜索算法(sparrow search algorithm,SSA)对ELM模型进行优化,并使用这3种优化算法(GA-ELM、PSO-ELM、SSA-ELM)构建少因子混合优化蒸散预测模型。结果表明:1)基于CART算法重要度排序结果,蒸散的主要影响因子依次是降水量、日照时数、平均本站气压、日最高气温、平均相对湿度。2)3种优化算法预测模型中,PSO-ELM模型的预测精度最高,23个站点的蒸散预测的均方根误差为6.608~22.077 mm/d,纳什效率系数为0.824~0.998,R2为0.908~0.995,平均绝对误差为5.075~16.677 mm/d。3)ELM模型在云贵高原区和四川盆地及周边地区有较好的适用性,3种优化算法在华南区和云贵高原区有较好的适用性,其中PSO-ELM模型的适用性最高。研究结果可为中国九大农业区域的作物需水量计算提供参考。

关键词：模型算法蒸散优化 CART ELM

Estimation of Chloride Diffusivity in Hydrated Tricalcium Silicate Using a Hydration-Diffusion Integrated Method

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 49-64页

作者： WANG Xin shen Dejian TAO Sijie LIU Ruixin WU shengxing College of Civil and Transportation Engineering Hohai UniversityNanjing 210098China

This study aims to develop a chloride diffusion simulation method that considers the hydration microstructure and pore solution properties during the hydration of tricalcium silicate(C3S).The method combines the hydration simulation,thermodynamic calculation,and finite element analysis to examine the effects of pore solution,including effect of electrochemical potential,effect of chemical activity,and effect of mechanical interactions between ions,on the chloride effective diffusion coefficient of hydrated C3S *** results indicate that the effect of electrochemical potential on chloride diffusion becomes stronger with increasing hydration age due to the increase in the content of hydrated calcium silicate;as the hydration age increases,the effect of chemical activity on chloride diffusion weakens when the number of diffusible elements decreases;the effect of mechanical interactions between ions on chloride diffusion decreases with the increase of hydration age.

关键词： tricalcium silicate simulation method chloride diffusion coefficient pore solution

Guiding phosphorus stewardship for multiple ecosystem services

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Ecosystem Health and Sustainability 2016年第12期2卷 29-41页

作者： Graham K.MacDonald Helen P.Jarvie Paul J.A.Withers Donnacha G.Doody Bonnie L.Keeler Philip M.Haygarth Laura T.Johnson Richard W.McDowell Michael K.Miyittah Stephen M.Powers Andrew N.Sharpley jianbo shen Douglas R.Smith Michael N.Weintraub Tiequan Zhang Department of Geography McGill University805 Sherbrooke Street WestMontrealQuebec H3A 0B9 Canada Centre for Ecology and Hydrology Wallingford OX108BB UK School of Environment Natural Resources and GeographyBangor UniversityBangor LL572UW UK Agri-Food and Biosciences Institute Belfast BT95PX UK Institute on the Environment University of MinnesotaSaint PaulMinnesota 55108 USA Lancaster Environment Centre Lancaster UniversityLancaster LA14YQ UK National Center for Water Quality Research Heidelberg University310 East Market StreetTiffinOhio 44883 USA Invermay Agricultural Centre AgResearchPrivate Bag 50034Mosgiel 9011 New Zealand Soil and Physical Sciences Faculty of Agriculture and Life SciencesLincoln UniversityPO Box 84Lincoln 7647 New Zealand Department of Environmental Sciences University of Cape CoastCape CoastGhana Center for Environmental Research Educationand Outreach(CEREO)Washington State UniversityPullmanWashington 99164 USA Division of Agriculture Department of CropSoiland Environmental SciencesUniversity of ArkansasFayettevilleArkansas 72701 USA Key Laboratory of Plant-Soil Interactions Department of Plant NutritionMinistry of EducationChina Agricultural UniversityBeijing 100193 China Grassland Soil and Water Research LaboratoryUSDA-ARS808 East Blackland RoadTempleTexas 76502 USA Department of Environmental Sciences University of ToledoToledoOhio 43606 USA Harrow Research and Development Center Agriculture and Agri-Food CanadaHarrowOntario N0R 1G0 Canada

The essential role of phosphorus(P)for agriculture and its impact on water quality has received decades of research ***,the benefits of sustainable P use and management for society due to its downstream impacts on multiple ecosystem services are rarely *** propose a conceptual framework-the“phosphorus-ecosystem services cascade”(PESC)-to integrate the key ecosystem processes and functions that moderate the relationship between P released to the environment from human actions and ecosystem services at distinct spatial and temporal *** pathways in the cascade via soil and aquatic processes link anthropogenic P to biodiversity and multiple services,including recreation,drinking water provision,and *** anthropogenic P cascades through catchments,it often shifts from a subsidy to a stressor of ecosystem *** stewardship can have emergent ecosystem service co-benefits due to synergies with other societal or management goals(e.g.,recycling of livestock manures and organic wastes could impact soil carbon storage).Applying the PESC framework,we identify key research priorities to align P stewardship with the management of multiple ecosystem services,such as incorporating additional services into agri-environmental P indices,assessing how widespread recycling of organic P sources could differentially impact agricultural yields and water quality,and accounting for shifting baselines in P stewardship due to climate ***,P impacts depend on site-specific agricultural and biogeophysical contexts,so greater precision in targeting stewardship strategies to specific locations would help to optimize for ecosystem services and to more effectively internalize the downstream costs of farm nutrient management.

关键词： agriculture ecosystem services phosphorus sustainability water quality

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面向县级林业的数据集成技术研究

计算机应用与软件 2018年第6期35卷 64-69页

作者：沈剑波雷渊才王功明符利勇中国林业科学研究院资源信息研究所北京100091 中国科学院生物物理研究所北京100101

目前精准林业越来越被关注,而树高、蓄积及生物量是研究森林生长与收获的定量指标。为了实现对这些数据进行快速计算及对数据库进行维护,研究开发了面向县级林业数据服务平台系统。该系统以VB6.0为开发语言,采用VBScript技术,以Access... 详细信息

目前精准林业越来越被关注,而树高、蓄积及生物量是研究森林生长与收获的定量指标。为了实现对这些数据进行快速计算及对数据库进行维护,研究开发了面向县级林业数据服务平台系统。该系统以VB6.0为开发语言,采用VBScript技术,以Access为后台数据库,实现了利用林分调查因子对树高、蓄积以及生物量的计算的功能。能按照关键字进行搜索查询,实现增加、删除、修改数据的功能,能够生成报表及导入数据。与传统的手工的方法相比,该系统有效提高了林业工作者的工作效率,并为精准林业打下良好的基础,为森林经营方案的制定提供有效的数据支持。

关键词：精准林业数据维护条件搜索 ADO技术

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澳洲坚果的营养特性与施肥管理途径

中国南方果树 2020年第1期49卷 149-154页

作者：董倩倩赵鑫倪书邦贺熙勇申建波中国农业大学资源与环境学院北京100193 云南省热带作物科学研究所云南景洪666100

澳洲坚果广泛种植于多个国家,其果实是优质食品,营养价值高,备受人们喜爱。我国是世界澳洲坚果第一种植大国,但与国外相比,我国澳洲坚果果园的施肥管理及诊断技术存在多种问题,尤其是施肥配比和施肥方法极不合理,不仅限制了澳洲坚果的产... 详细信息

澳洲坚果广泛种植于多个国家,其果实是优质食品,营养价值高,备受人们喜爱。我国是世界澳洲坚果第一种植大国,但与国外相比,我国澳洲坚果果园的施肥管理及诊断技术存在多种问题,尤其是施肥配比和施肥方法极不合理,不仅限制了澳洲坚果的产量,而且显著降低了坚果的品质。目前,有关澳洲坚果果园土壤、叶片营养特性以及施肥管理技术的系统性研究很少。本文综合了国内外的最新研究进展,系统总结了我国澳洲坚果的施肥管理问题,并综述目前澳洲坚果存在的土壤及叶片营养诊断问题,及叶片缺素症状的解决措施。

关键词：澳洲坚果营养诊断施肥技术缺素症状