检索结果-南通市图书馆

Simulations of electron zebra stripes in the inner radiation belt using a composite empirical electric field model

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2025年第1期68卷 27-38页

作者： Ziyang WANG ying LIU Qiugang ZONG Hong ZOU Yuguang YE Xuzhi ZHOU Chao YUE Shan WANG Institute of Space Physics and Applied Technology Peking University State Key Laboratory of Lunar and Planetary Science Macau University of Science and Technology

The phenomenon termed “zebra stripes” manifests as regular patterns in the energy-space(L shell) spectrum of energetic electrons(ranging from tens to hundreds ke V) within the inner radiation belt. These structures exhibit drift-periodic behavior and commonly arise from large-scale electric field perturbations near the substorm onsets. In this study, we introduce a composite electric field model and replicate the formation, structure, and evolution of zebra stripes using a bounce-averaged test particle code under this electric field model. High-resolution measurements of energetic electrons obtained from the Van Allen Probes and the recently launched Macao Science Satellites-1 are used as initial conditions and served to validate our test particle simulations. Comparative analyses between observed data and simulations demonstrate our test particle method's efficacy in capturing zebra stripes' general behavior. Moreover, the composite model proves capable of reproducing realistic variations in the electric field within the inner radiation belt to a certain extent. Nevertheless, subtle differences emerge in the flux strength and the positions of stripes. These disparities primarily stem from limitations inherent in the electric field model and the initial conditions of the simulation. Acknowledging that the model represents an average case, it is conceivable that real-world scenarios may deviate from the average, thereby introducing variations in the observed phenomena.

关键词： Zebra stripes Inner radiation belt Large-scale electric fields Van Allen Probes Macao Science Satellite

Multi-model ensemble learning for battery state-of-health estimation:Recent advances and perspectives

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2025年第1期100卷 739-759页

作者： Chuanping Lin Jun Xu Delong Jiang Jiayang Hou ying Liang Zhongyue Zou Xuesong Mei State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University Shaanxi Key Laboratory of Intelligent Robots School of Mechanical Engineering Xi'an Jiaotong University Department of Electrical Engineering and Automation Luoyang Institute of Science and Technology School of Mechanical Engineering Hangzhou Dianzi University

The burgeoning market for lithium-ion batteries has stimulated a growing need for more reliable battery performance monitoring. Accurate state-of-health(SOH) estimation is critical for ensuring battery operational performance. Despite numerous data-driven methods reported in existing research for battery SOH estimation, these methods often exhibit inconsistent performance across different application scenarios. To address this issue and overcome the performance limitations of individual data-driven models,integrating multiple models for SOH estimation has received considerable attention. Ensemble learning(EL) typically leverages the strengths of multiple base models to achieve more robust and accurate outputs. However, the lack of a clear review of current research hinders the further development of ensemble methods in SOH estimation. Therefore, this paper comprehensively reviews multi-model ensemble learning methods for battery SOH estimation. First, existing ensemble methods are systematically categorized into 6 classes based on their combination strategies. Different realizations and underlying connections are meticulously analyzed for each category of EL methods, highlighting distinctions, innovations, and typical applications. Subsequently, these ensemble methods are comprehensively compared in terms of base models, combination strategies, and publication trends. Evaluations across 6 dimensions underscore the outstanding performance of stacking-based ensemble methods. Following this, these ensemble methods are further inspected from the perspectives of weighted ensemble and diversity, aiming to inspire potential approaches for enhancing ensemble performance. Moreover, addressing challenges such as base model selection, measuring model robustness and uncertainty, and interpretability of ensemble models in practical applications is emphasized. Finally, future research prospects are outlined, specifically noting that deep learning ensemble is poised to advance ens

关键词： Contrastive Learning

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

不同氮素水平下生物菌肥施用效果研究

山西农业科学 2006年第1期34卷 50-52页

作者：郝晶刘冰谢英荷洪坚平山西农业大学资源与环境学院山西太谷030801

通过盆栽玉米试验,研究生物菌肥在不同土壤氮素水平下对土壤生物量氮、细菌等各菌群数量及玉米地上部分株高、叶面积等的影响,结果表明:在高、中、低氮素水平下,加菌肥比不加菌肥处理的土壤固氮菌、磷细菌、细菌、放线菌、真菌、生物量... 详细信息

通过盆栽玉米试验,研究生物菌肥在不同土壤氮素水平下对土壤生物量氮、细菌等各菌群数量及玉米地上部分株高、叶面积等的影响,结果表明:在高、中、低氮素水平下,加菌肥比不加菌肥处理的土壤固氮菌、磷细菌、细菌、放线菌、真菌、生物量氮等都有明显提高,而且在中氮水平下更为显著,氮素水平过高或过低均不利于菌肥肥效的发挥。

关键词：生物菌肥生物量氮微生物数量

在线全文

学校读者我要写书评

暂无评论

系统论视域下高校实践育人共同体建设探析

黑龙江高教研究 2025年第1期43卷 112-117页

作者：何莹李春梅西南交通大学四川成都611756

实践育人是高校思想政治工作的重要环节,高校实践育人共同体建设是高校实践育人工作的重要抓手。高校实践育人共同体作为一个复杂的系统,与系统的整体性、层次性、协同性等特征相契合,具有丰富的系统意蕴。基于系统论视域,发现高校实践... 详细信息

实践育人是高校思想政治工作的重要环节,高校实践育人共同体建设是高校实践育人工作的重要抓手。高校实践育人共同体作为一个复杂的系统,与系统的整体性、层次性、协同性等特征相契合,具有丰富的系统意蕴。基于系统论视域,发现高校实践育人共同体建设仍存在理念偏差、动力不强、协作不畅、对接不足等系统困境,并从系统集成的深度和广度上提出优化高校实践育人共同体建设的“内部要素协调+外部环境互动”模式,通过建章立制、凝聚共识,契合需求、激发动力,整合资源、协同共建,统筹规划、因时而新等路径,实现高校实践育人共同体建设的系统集成,提升高校实践育人共同体的育人实效。

关键词：系统论系统集成实践育人共同体建设

Cd、Cr、Pb对几种叶类蔬菜生长状况及品质的影响

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

山西农业科学 2008年第4期36卷 20-22页

作者：李廷亮谢英荷刘子娇山西农业大学资源与环境学院山西太谷030801

研究通过盆栽试验,比较了Cd、Cr、Pb对几种叶类蔬菜生长状况及品质的影响,旨在为提高蔬菜品质,控制蔬菜重金属污染提供科学依据。结果表明:(1)重金属对叶类蔬菜生长及品质的影响因重金属种类和蔬菜品种而异。Pb处理对各蔬菜的品质影响... 详细信息

研究通过盆栽试验,比较了Cd、Cr、Pb对几种叶类蔬菜生长状况及品质的影响,旨在为提高蔬菜品质,控制蔬菜重金属污染提供科学依据。结果表明:(1)重金属对叶类蔬菜生长及品质的影响因重金属种类和蔬菜品种而异。Pb处理对各蔬菜的品质影响不明显;Cr对新上海青油菜,苏州青油菜,四月慢油菜的影响最严重;莜麦生菜对Cd比较敏感;小叶茼蒿受三种重金属影响最小,表现出一定的耐性;(2)五种蔬菜对重金属的富集能力均表现为Cd>Cr>Pb;四月慢油菜对Cd、Pb富集能力最强,苏州青油菜对Cd、Pb的富集系数最小,莜麦生菜对Cr的富集系数最小。因此在Cd、Pb污染的土壤中可以考虑种植苏州青油菜为宜,在一些Cr轻度污染区以种植莜麦生菜为宜,以达到边利用边改良污染土壤的目的。

关键词：重金属蔬菜品质富集

2009,2010年襄汾旱地冬小麦生产现状分析

在线全文

学校读者我要写书评

暂无评论

山西农业科学 2011年第4期39卷 332-335,338页

作者：马红梅谢英荷洪坚平山西农业大学资源与环境学院山西太谷030801

为了了解山西省旱地冬小麦生产现状,2009,2010年分别对山西省襄汾县150户和96户农户的旱地冬小麦生产现状进行了调查分析。结果表明:(1)该地区这2年冬小麦生产有90.67%和73.93%的农户产量低于4 000 kg/hm2,仅有9.33%和26.07%的农户产量... 详细信息

为了了解山西省旱地冬小麦生产现状,2009,2010年分别对山西省襄汾县150户和96户农户的旱地冬小麦生产现状进行了调查分析。结果表明:(1)该地区这2年冬小麦生产有90.67%和73.93%的农户产量低于4 000 kg/hm2,仅有9.33%和26.07%的农户产量大于4 000 kg/hm2,平均产量2009年为1 467 kg/hm2,2010年为3 366 kg/hm2,均低于我国平均水平和发达国家水平。(2)2009年氮肥用量平均为118.76 kg/hm2,2010年为146.69 kg/hm2,小于120 kg/hm2的农户分别占25.33%和53.13%,大于120 kg/hm2的农户分别占74.67%和46.87%。(3)2009年磷用量平均为62.78 kg/hm2,2010年为95.40 kg/hm2;2009年钾的平均用量为11.39 kg/hm2,2010年为55.66 kg/hm2。2009年90.00%的农户和2010年53.13%的农户磷肥用量不能满足小麦的需要,钾肥不足更严重。(4)2009年只以种肥方式一次性投入,且几乎都是化肥,有机肥只通过留茬翻压,没有施基肥和追肥。2010年有种肥、基肥和追肥,但只有1户用有机肥。(5)2年灌溉次数分别为52,138次,灌水严重不足,灌溉次数和产量呈正相关。合理施肥和灌溉是山西旱地冬小麦产量上新台阶的唯一途径。

关键词：襄汾县旱地小麦产量施肥灌溉

在线全文

学校读者我要写书评

暂无评论

五株耐铅菌株对油菜植株营养元素的影响

山西农业大学学报（自然科学版） 2009年第5期29卷 407-411页

作者：陈灿灿谢英荷洪坚平山西农业大学信息学院山西晋中030600 山西农业大学资源与环境学院山西太谷030801

在室内筛选的基础上,从当地石灰性土壤中分离出五株耐铅菌株,分别标记为M1、M2、M3、M4、M5,其中M1、M2为细菌,M3为放线菌,M4、M5为真菌,通过盆栽实验,研究其在不同浓度下对油菜养分的影响。研究表明:施加菌株M2、M3、M4和M5均对油菜氮... 详细信息

在室内筛选的基础上,从当地石灰性土壤中分离出五株耐铅菌株,分别标记为M1、M2、M3、M4、M5,其中M1、M2为细菌,M3为放线菌,M4、M5为真菌,通过盆栽实验,研究其在不同浓度下对油菜养分的影响。研究表明:施加菌株M2、M3、M4和M5均对油菜氮磷的吸收均有显著促进作用,菌株M1却抑制了油菜对氮磷的吸收,施加菌株M3和M4油菜钾含量与对照相比略有升高,但差异均不显著,菌株M1、M2和M5显著抑制了植株对钾的吸收,抑制作用最大的是菌株M5,与对照相比降低了22%。

关键词：耐铅菌株油菜养分

Visualizing charge transfer and nuclear quantum effects in the hydrogen bond network of water

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2025年

作者： ying Gao Haotian Wang Bin Zhang Department of Chemistry School of Science Tianjin University

Water, one of the most common and important solvents on earth, is widely used in biology, physics, chemistry, and other fields [1]. The hydrogen bond interactions between water molecules form a highly dynamic and syne...

关键词：

Tangled but ordered human mitochondrial tRNA maturation

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China Life Sciences 2025年

作者： Shi-ying Yao Xiao-Long Zhou Key Laboratory of RNA Innovation Science and Engineering CAS Center for Excellence in Molecular Cell Science Shanghai Institute of Biochemistry and Cell Biology Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory of Systems health Science of Zhejiang Province School of Life Science Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences

Mitochondria are cellular organelles that originate from an endosymbiotic bacterial ancestor and are primarily responsible for ATP generation via oxidative phosphorylation (OXPHOS). OXPHOS is conducted by five mitochondrial respiratory complexes in the inner mitochondrial membrane. Human mitochondria possess a distinct genome, a small, circular, doublestranded DNA (mtDNA) of 16,569 base pairs.

关键词：