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基于Stable Diffusion的虚拟人形象预设计的应用与研究 被引量:2
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作者 曾建勇 沈晓萍 《现代信息科技》 2024年第3期169-175,共7页
对当前AIGC在虚拟形象预设计方面的现状及影响进行了分析和探讨。以Stable Diffusion为例,详细介绍了工程构建和实现,对相关模块的作用、运行环境、使用方法及其指令等多个方面进行了综合叙述、分析和探讨,针对使用不同采样方法、不同... 对当前AIGC在虚拟形象预设计方面的现状及影响进行了分析和探讨。以Stable Diffusion为例,详细介绍了工程构建和实现,对相关模块的作用、运行环境、使用方法及其指令等多个方面进行了综合叙述、分析和探讨,针对使用不同采样方法、不同采样参数及不同训练模型生成图片效果的优劣进行了说明及展示。随后,通过项目实例,完整地展示了人物形象预设计的过程。最后,对AIGC等新技术可能带来的社会影响进行了预测和总结。 展开更多
关键词 AI生成内容 stable Diffusion 生成对抗网络 提示词 虚拟人形象
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TiN/Fe_(2)N/C composite with stable and broadband high-temperature microwave absorption 被引量:1
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作者 Yahong Zhang Yi Zhang +5 位作者 Huimin Liu Dan Li Yibo Wang Chunchao Xu Yuping Tian Hongjie Meng 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第11期2508-2517,共10页
Facing the complex variable high-temperature environment,electromagnetic wave(EMW)absorbing materials maintaining high stability and satisfying absorbing properties is essential.This study focused on the synthesis and... Facing the complex variable high-temperature environment,electromagnetic wave(EMW)absorbing materials maintaining high stability and satisfying absorbing properties is essential.This study focused on the synthesis and EMW absorbing performance evaluation of TiN/Fe_(2)N/C composite materials,which were prepared using electrostatic spinning followed by a high-temperature nitridation process.The TiN/Fe_(2)N/C fibers constructed a well-developed conductive network that generates considerable conduction loss.The heterogeneous interfaces between different components generated a significant level of interfacial polarization.Thanks to the synergistic effect of stable dielectric loss and optimized impedance matching,the TiN/Fe_(2)N/C composite materials demonstrated excellent and stable absorption performance across a wide temperature range(293-453 K).Moreover,TiN/Fe_(2)N/C-15 achieved a minimum reflection loss(RL)of−48.01 dB and an effective absorption bandwidth(EAB)of 3.64 GHz at 2.1 mm and 373 K.This work provides new insights into the development of high-efficiency and stabile EMW absorbing materials under complex variable high-temperature conditions. 展开更多
关键词 high-temperature impedance matching stable permittivity dielectric loss
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Rising utilization of stable isotopes in tree rings for climate change and forest ecology 被引量:1
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作者 Ru Huang Chenxi Xu +3 位作者 Jussi Grießinger Xiaoyu Feng Haifeng Zhu Achim Bräuning 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期103-116,共14页
Analyses of stable isotopes(C,O,H)in tree rings are increasingly important cross-disciplinary programs.The rapid development in this field documented in an increasing number of publications requires a comprehensive re... Analyses of stable isotopes(C,O,H)in tree rings are increasingly important cross-disciplinary programs.The rapid development in this field documented in an increasing number of publications requires a comprehensive review.This study includes a bibliometric analysis-based review to better understand research trends in tree ring stable isotope research.Overall,1475 publications were selected from the Web of Science Core Collection for 1974-2023.The findings are that:(1)numbers of annual publications and citations increased since 1974.From 1974 to 1980,there were around two relevant publications per year.However,from 2020 to 2022,this rose sharply to 109 publications per year.Likewise,average article citations were less than four per year before 1990,but were around four per article per year after 2000;(2)the major subjects using tree ring stable isotopes include forestry,geosciences,and environmental sciences,contributing to 42.5%of the total during 1974-2023;(3)the top three most productive institutions are the Chinese Academy of Sciences(423),the Swiss Federal Institute for Forest,Snow and Landscape Research(227),and the University of Arizona(204).These achievements result from strong collaborations;(4)review papers,for example,(Dawson et al.,Annu Rev Ecol Syst 33:507-559,2002)and(McCarroll and Loader,Quat Sci Rev 23:771-801,2004),are among the most cited,with more than 1000 citations;(5)tree ring stable isotope studies mainly focus on climatology and ecology,with atmospheric CO_(2) one of the most popular topics.Since 2010,precipitation and drought have received increasing attention.Based on this analysis,the research stages,key findings,debated issues,limitations and direc-tions for future research are summarized.This study serves as an important attempt to understand the progress on the use of stable isotopes in tree rings,providing scientific guid-ance for young researchers in this field. 展开更多
关键词 Tree rings stable isotopes Web of Science BIBLIOMETRIC
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Software Defect Prediction Method Based on Stable Learning 被引量:1
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作者 Xin Fan Jingen Mao +3 位作者 Liangjue Lian Li Yu Wei Zheng Yun Ge 《Computers, Materials & Continua》 SCIE EI 2024年第1期65-84,共20页
The purpose of software defect prediction is to identify defect-prone code modules to assist software quality assurance teams with the appropriate allocation of resources and labor.In previous software defect predicti... The purpose of software defect prediction is to identify defect-prone code modules to assist software quality assurance teams with the appropriate allocation of resources and labor.In previous software defect prediction studies,transfer learning was effective in solving the problem of inconsistent project data distribution.However,target projects often lack sufficient data,which affects the performance of the transfer learning model.In addition,the presence of uncorrelated features between projects can decrease the prediction accuracy of the transfer learning model.To address these problems,this article propose a software defect prediction method based on stable learning(SDP-SL)that combines code visualization techniques and residual networks.This method first transforms code files into code images using code visualization techniques and then constructs a defect prediction model based on these code images.During the model training process,target project data are not required as prior knowledge.Following the principles of stable learning,this paper dynamically adjusted the weights of source project samples to eliminate dependencies between features,thereby capturing the“invariance mechanism”within the data.This approach explores the genuine relationship between code defect features and labels,thereby enhancing defect prediction performance.To evaluate the performance of SDP-SL,this article conducted comparative experiments on 10 open-source projects in the PROMISE dataset.The experimental results demonstrated that in terms of the F-measure,the proposed SDP-SL method outperformed other within-project defect prediction methods by 2.11%-44.03%.In cross-project defect prediction,the SDP-SL method provided an improvement of 5.89%-25.46% in prediction performance compared to other cross-project defect prediction methods.Therefore,SDP-SL can effectively enhance within-and cross-project defect predictions. 展开更多
关键词 Software defect prediction code visualization stable learning sample reweight residual network
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Method to measure tree-ring width,density,elemental composition,and stable carbon and oxygen isotopes using one sample 被引量:1
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作者 Chenxi Xu Yaru Zhao +4 位作者 Wenling An Qingyu Zhao Yucheng Liu Masaki Sano Takeshi Nakatsuka 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期167-174,共8页
Tree-ring width(RW),density,elemental com-position,and stable carbon and oxygen isotope(δ^(13)C,δ^(18)O)are widely used as proxies to assess climate change,ecology,and environmental pollution;however,a specific pret... Tree-ring width(RW),density,elemental com-position,and stable carbon and oxygen isotope(δ^(13)C,δ^(18)O)are widely used as proxies to assess climate change,ecology,and environmental pollution;however,a specific pretreat-ment has been needed for each proxy.Here,we developed a method by which each proxy can be measured in the same sample.First,the sample is polished for ring width meas-urement.After obtaining the ring width data,the sample is cut to form a 1-mm-thick wood plate.The sample is then mounted in a vertical sample holder,and gradually scanned by an X-ray beam.Simultaneously,the count rates of the fluorescent photons of elements(for chemical characteriza-tion)and a radiographic grayscale image(for wood density)are obtained,i.e.the density and the element content are obtained.Then,cellulose is isolated from the 1-mm wood plate by removal of lignin,and hemicellulose.After producing this cellulose plate,cellulose subsamples are separated by knife under the microscope for inter-annual and intra-annual stable carbon and oxygen isotope(δ^(13)C,δ^(18)O)analysis.Based on this method,RW,density,elemental composition,δ^(13)C,and δ^(18)O can be measured from the same sample,which reduces sample amount and treatment time,and is helpful for multi-proxy comparison and combination research. 展开更多
关键词 Tree-ring width Tree-ring density Tree-ring elemental composition Tree-ring stable carbon and oxygenisotopes
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Multi-Model Approach for Assessing the Influence of Calibration Criteria on the Water Balance in Ouémé Basin
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作者 Aymar Yaovi Bossa Mahutin Aristide Oluwatobi Kpossou +1 位作者 Jean Hounkpè Félicien Djigbo Badou 《Journal of Water Resource and Protection》 CAS 2024年第3期207-218,共12页
Hydrological models are very useful tools for evaluating water resources, and the hydroclimatic hazards associated with the water cycle. However, their calibration and validation require the use of performance criteri... Hydrological models are very useful tools for evaluating water resources, and the hydroclimatic hazards associated with the water cycle. However, their calibration and validation require the use of performance criteria which choice is not straightforward. This paper aims to evaluate the influence of the performance criteria on water balance components and water extremes using two global rainfall-runoff models (HBV and GR4J) over the Ouémé watershed at the Bonou and Savè outlets. Three (3) Efficacy criteria (Nash, coefficient of determination, and KGE) were considered for calibration and validation. The results show that the Nash criterion provides a good assessment of the simulation of the different parts of the hydrograph. KGE is better for simulating peak flows and water balance elements than other efficiency criteria. This study could serve as a basis for the choice of performance criteria in hydrological modelling. 展开更多
关键词 Hydrological Modelling Performance criteria Water Balance Ouémé Basin
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Unequal Distribution of Innovation Efforts for Neglected Tropical Diseases: The Role of Funding Evaluation Criteria
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作者 Anne M. G. Neevel Kenneth D. S. Fernald Linda H. M. van de Burgwal 《Health》 2024年第5期490-520,共31页
Background: International research and innovation efforts for neglected tropical diseases have increased in recent decades due to disparities in overall health research funding in relation to global burden of disease.... Background: International research and innovation efforts for neglected tropical diseases have increased in recent decades due to disparities in overall health research funding in relation to global burden of disease. However, within the field of neglected tropical diseases some seem far more neglected than others. In this research the aim is to investigate the distribution of resources and efforts, as well as the mechanisms that underpin funding allocation for neglected tropical diseases. Methodology: A systematic literature review was conducted to establish a comprehensive overview of known indicators for innovation efforts related to a wide range of neglected tropical diseases. Articles were selected based on a subjective evaluation of their relevance, the presence of original data, and the breadth of their scope. This was followed by thirteen in-depth open-ended interviews with representatives of private, public and philanthropic funding organizations, concerning evaluation criteria for funding research proposals. Results: The findings reveal a large difference in the extent to which the individual diseases are neglected with notable differences between absolute and relative efforts. Criteria used in the evaluation of research proposals relate to potential impact, the probability of success and strategic fit. Private organizations prioritize strategic fit and economic impact;philanthropic organizations prioritize short-term societal impact;and public generally prioritize the probability of success by accounting for follow-up funding and involvement of industry. Funding decisions of different types of organizations are highly interrelated. Conclusions: This study shows that the evaluation of funding proposals introduces and retains unequal funding distribution, reinforcing the relative neglect of diseases. Societal impact is the primary rationale for funding but application of it as a funding criterion is associated with significant challenges. Furthermore, current application of evaluation criteria leads to a primary focus on short-term impact. Through current practice, the relatively most neglected diseases will remain so, and a long-term strategy is needed to resolve this. 展开更多
关键词 Neglected Tropical Diseases Funding Decision Evaluation criteria Health Research Funding Research Impact
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A bulk extraction method to determine the stable isotope ratios of iron,nickel,copper,zinc,and cadmium in seawater using multi-collector inductively coupled plasma mass spectrometry
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作者 Zhan Shen Yuncong Ge +3 位作者 Jiahui Liu Wenkai Guan Wenfeng Hu Ruifeng Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第7期125-137,共13页
The oceanic trace metals iron(Fe),nickel(Ni),copper(Cu),zinc(Zn),and cadmium(Cd)are crucial to marine phytoplankton growth and global carbon cycle,and the analysis of their stable isotopes can provide valuable insight... The oceanic trace metals iron(Fe),nickel(Ni),copper(Cu),zinc(Zn),and cadmium(Cd)are crucial to marine phytoplankton growth and global carbon cycle,and the analysis of their stable isotopes can provide valuable insights into their biogeochemical cycles within the ocean.However,the simultaneous isotopic analysis of multiple elements present in seawater is challenging because of their low concentrations,limited volumes of the test samples,and high salt matrix.In this study,we present the novel method developed for the simultaneous analysis of five isotope systems by 1 L seawater sample.In the developed method,the NOBIAS Chelate-PA1 resin was used to extract metals from seawater,the AG MP-1M anion-exchange resin to purify Cu,Fe,Zn,Cd,and the NOBIAS Chelate-PA1 resin to further extract Ni from the matrix elements.Finally,a multi-collector inductively coupled plasma mass spectroscope(MC-ICPMS)was employed for the isotopic measurements using a doublespike technique or sample-standard bracketing combined with internal normalization.This method exhibited low total procedural blanks(0.04 pg,0.04 pg,0.21 pg,0.15 pg,and 3 pg for Ni,Cu,Fe,Zn,and Cd,respectively)and high extraction efficiencies(100.5%±0.3%,100.2%±0.5%,97.8%±1.4%,99.9%±0.8%,and 100.1%±0.2%for Ni,Cu,Fe,Zn,and Cd,respectively).The external errors and external precisions of this method could be considered negligible.The proposed method was further tested on the seawater samples obtained from the whole vertical profile of a water column during the Chinese GEOTRACES GP09 cruise in the Northwest Pacific,and the results showed good agreement with previous related data.This innovative method will contribute to the advancement of isotope research and enhance our understanding of the marine biogeochemical cycling of Fe,Ni,Cu,Zn,and Cd. 展开更多
关键词 trace metal stable isotopes seawater bulk extraction
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Distribution and sources of sedimentary organic matter in different aquaculture areas of northeastern Zhanjiang Bay using stable carbon and nitrogen isotopes
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作者 Fengxia Zhou Shuangling Wang +8 位作者 Han Fang Jiani He Liang Ye Zhaohai Ding Cuiting Li Fajin Chen Xuan Lu Chunqing Chen Yafei Meng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第6期38-48,共11页
Zhanjiang Bay is a major aquaculture area in China with many types of mariculture products(such as oysters,fish,and shrimp).The culture area and shrimp output in Zhanjiang Bay are ranked first in China.We investigated... Zhanjiang Bay is a major aquaculture area in China with many types of mariculture products(such as oysters,fish,and shrimp).The culture area and shrimp output in Zhanjiang Bay are ranked first in China.We investigated the total organic carbon(TOC),total nitrogen(TN),TOC/TN ratio,and stable isotopes(δ^(13)C and δ^(15)N) of the fish and shrimp feed,fish and shrimp feces,and sedimentary organic matter(SOM) in and around different aquaculture areas of northeastern Zhanjiang B ay to study the impact of aquaculture activities on SOM.The average TOC contents of fish and shrimp feed were 39.20%±0.91% and 39.29%±0.21%,respectively.The average TOC content in the surface sediments of the oyster culture area,the mixed(fish and shrimp) culture area,and the cage fish farm area were 0.66%,0.88%±0.10%,and 0.58%±0.19%,respectively,which may indicate that mixed culture had a greater impact on SOM.The relatively high TOC and TN contents and relatively low TOC/TN ratios,and δ^(15)N values in the upper layer of the core sediment in the mixed culture area could also support the significant influence of mixed culture.The average δ^(13)C and δ^(15)N values of fish and shrimp feed were -20.6‰±2.2‰ and 1.8‰±1.2‰,respectively,which were different from the isotopic values of SOM in the study area.δ^(13)C and δ^(15)N values for SOM in different aquaculture areas were different from those of nearby reference stations,probably reflecting the influence of aquaculture.The δ^(13)C and δ^(15)N values in the oyster culture area(-25.9‰ and6.0‰,respectively) seemed to have reduced δ^(13)C and enriched δ^(15)N relative to those of the reference station(-24.6‰ and 5.8‰,respectively).This may reflect the influence of organic matter on oyster culture.The δ^(15)N value of the station in the mixed culture area(7.1‰±0.4‰) seemed to be relatively enriched in δ^(15)N relative to that of the reference station(6.6‰).Sedimentation and the subsequent degradation of organic matter from mixed cultures may have contributed to this phenomenon.The surface sediment at the cage fish farm area seemed to be affected by fish feces and primary production based on the indication of δ^(13)C and δ^(15)N values.The sediment core at the mixed culture region(NS6) had lower TOC/TN ratios and more positive δ^(13)C and δ^(15)N values than the sediment core at the oyster culture area,suggesting a higher proportionate contribution of marine organic matter in the mixed culture area.In summary,oyster culture,mixed culture,and cage fish culture in northeastern Zhanjiang Bay had a certain degree of impact on SOM,and mixed culture had more significant influences on SOM based on the high TOC contents and the significant vertical variations of TOC/TN ratio and δ^(15)N value in the sediment of this area.This study provides new insights into the impact of aquaculture activities on SOM content. 展开更多
关键词 sedimentary organic matter AQUACULTURE stable isotopes SOURCES Zhanjiang Bay
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AIGC在艺术设计专业领域的神助攻——以Stable Diffusion为例 被引量:9
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作者 陈英 马洪涛 《服装设计师》 2024年第1期73-84,共12页
AIGC(Artificial Intelligence Generated Content,人工智能生成内容)作为新兴的人工智能生产力引擎,代表了新时代科技进步的崭新面貌,从感知、理解世界到创造、生成世界,AI技术的底层技术和产业生态已形成全球性的崭新格局。AIGC在艺... AIGC(Artificial Intelligence Generated Content,人工智能生成内容)作为新兴的人工智能生产力引擎,代表了新时代科技进步的崭新面貌,从感知、理解世界到创造、生成世界,AI技术的底层技术和产业生态已形成全球性的崭新格局。AIGC在艺术与设计专业领域的应用中备受瞩目,通过利用机器学习和深度学习技术,能自动生成各种形式的内容,包括图像、文字、音频等,已经逐渐成为艺术设计专业师生创作的重要辅助工具。通过稳定扩散模型(Stable Diffusion,SD)实例介绍AIGC如何帮助学生或设计师快速获取灵感、提高创作效率以及增强作品的独特性和创新性。首先,艺术设计中常常会面临创作灵感枯竭的困境,而AIGC能快速生成大量创意和灵感。例如,通过使用图像生成算法,SD能自动生成与艺术作品主题相关的各种不同艺术风格的图像,帮助学生或设计师迅速获取灵感并拓展创作思路[1]。其次,在艺术与设计领域,完成作品需要投入大量的时间和精力,而SD能自动完成一些繁琐的任务,如线稿上色、手绘转3D模型等。学生或设计师可以将更多的时间和精力投入到创意和构思上,后期精细化处理,从而提高创作效率。此外,SD生成的创意和灵感是基于算法和数据集进行的,因此能产生出一些独特的、创新的内容。这些内容往往能够为艺术与设计作品带来更多的想象力和表现力,使作品更加吸引眼球。总的来说,AIGC在艺术与设计专业领域中发挥着越来越重要的作用。[2]它不仅可以帮助学生和设计师快速获取灵感和提高创作效率,还能够增强作品的独特性和创新性,已逐渐成为艺术创作的重要辅助力量。AI可以模仿人类艺术家的创作过程,但AI本身是没有能力创作的,它无法像人类那样融入自身的情感、灵性和创新思维。因此,AI并不会淘汰艺术设计师们,反而将成为艺术设计师们的得力助手。我们可以预见AIGC科技与艺术设计师的结合将是未来艺术专业设计领域的必然趋势。这种融合将为艺术创作领域带来更为广阔的舞台。 展开更多
关键词 人工智能生成内容 艺术创作 稳定扩散
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Local Criteria Used by Farmers to Evaluate the Agronomic Performance and the Fertilizing Capacity of Cowpea Varieties: Diversity, Variability and Proximal Relation with Agronomic Measurements in Contrasted Sahelian Locations
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作者 Nouhou Salifou Jangorzo Abdoul-Aziz Saïdou +2 位作者 Abou-Soufianou Sadda Abdoulaye Moussa Mamoudou Hassane Bil-Assanou Issoufou 《Agricultural Sciences》 2024年第1期114-131,共18页
When contributing to participatory research, farmers usually appreciate the performance of cowpea varieties using qualitative scores. The score they attribute to each variety are based on local knowledge. The specific... When contributing to participatory research, farmers usually appreciate the performance of cowpea varieties using qualitative scores. The score they attribute to each variety are based on local knowledge. The specific criteria they individually use to attribute a score are not well described. The objectives of this work were to: 1) identify and describe exhaustively the local criteria used by farmers to measure the agronomic performance of cowpea;2) assess the variability and statistical structure of these farmer criteria across local contexts;3) and analyze the association between these farmer criteria and the classical agronomic measurement. To achieve these objectives, an augmented block design was implemented across fifteen locations in the regions of Maradi, Dosso and Tillabéri, representing a diversity of local contexts. From a set of 36 cowpea varieties, fifteen varieties were sown per location, including five varieties (controls) common to all locations. In each location, two replicates were sown in randomized Fisher’s blocks. After agronomic measurement and participatory evaluation (scoring of varieties by farmers), a group survey (focus group) was conducted in each location to identify the criteria considered by farmers to found their discretional scoring of varieties during the participatory evaluation. The analysis of the data identified, across locations, thirteen criteria defined by farmers to characterize the agronomic performance of cowpea. Some of these criteria were different according to location. Farmers ranked the three varieties with the best performance for each agronomical trait (Top 3 varieties). A comparison of the farmer ranking with the ranking based on agronomic measurements revealed similarity and complementary between both methods. This study highlighted the importance of considering both local and scientific knowledge in local varietal evaluations. 展开更多
关键词 Agronomic Performance Participatory Research COWPEA Farmers’ criteria
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基于AFF-Stablenet模型的小样本轴承故障诊断
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作者 郭康 王志刚 徐增丙 《现代制造工程》 CSCD 北大核心 2024年第9期144-151,53,共9页
针对滚动轴承在小样本条件下诊断准确率低和泛化性弱的问题,提出了一种基于注意力特征融合的深度稳定学习(Attention Feature Fusion and Deep Stable Learning,AFF-Stablenet)模型的故障诊断方法。该方法首先使用经验模态分解(Empirica... 针对滚动轴承在小样本条件下诊断准确率低和泛化性弱的问题,提出了一种基于注意力特征融合的深度稳定学习(Attention Feature Fusion and Deep Stable Learning,AFF-Stablenet)模型的故障诊断方法。该方法首先使用经验模态分解(Empirical Mode Decompositim,EMD)将样本分解成多段频率的子信号,求取子信号与原始信号的互相关系数,选择系数较高的前三阶子信号;利用连续小波变换(Continuws Narelet Transorm,CWT)将子信号转换为时频图表示,通过注意力特征融合的方式将这些时频图特征进行融合;最后将融合特征输入到深度稳定学习(Stablenet)模型进行训练与预测。为验证模型的有效性,采用凯斯西储大学轴承数据集进行各组对比试验,都灵理工大学轴承数据集进行验证。实验结果表明,AFF-Stablenet模型在小样本情况下的泛化性和鲁棒性均强于其他对比模型,证明了模型的优越性。 展开更多
关键词 注意特征融合 深度稳定学习 滚动轴承 小样本 故障诊断
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Stable multi-electron reaction stimulated by W doping VS_(4)for enhancing magnesium storage performance
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作者 Yuxin Tian Jiankang Chen +7 位作者 Guofeng Wang Bing Sun Alan Meng Lei Wang Guicun Li Jianfeng Huang Shiqi Ding Zhenjiang Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期89-98,I0004,共11页
Rechargeable magnesium batteries(RMBs)hold promise for offering higher volumetric energy density and safety features,attracting increasing research interest as the next post lithium-ion batteries.Developing high perfo... Rechargeable magnesium batteries(RMBs)hold promise for offering higher volumetric energy density and safety features,attracting increasing research interest as the next post lithium-ion batteries.Developing high performance cathode material by inducing multi-electron reaction process as well as maintaining structural stability is the key to the development and application of RMBs.Herein,multielectron reaction occurred in VS_(4)by simple W doping strategy.W doping induces valence of partial V as V^(2+)and V^(3+)in VS_(4)structure,and then stimulates electrochemical reaction involving multi-electrons in 0.5%W-V-S.The flower-like microsphere morphology as well as rich S vacancies is also modulated by W doping to neutralize structure change in such multi-electron reaction process.The fabricated 0.5%W-V-S delivers higher specific capacity(149.3 m A h g^(-1)at 50 m A g^(-1),which is 1.6 times higher than that of VS_(4)),superior rate capability(76 mA h g^(-1)at 1000 mA g^(-1)),and stable cycling performance(1500cycles with capacity retention ratio of 93.8%).Besides that,pesudocapaticance-like contribution analysis as well as galvanostatic intermittent titration technique(GITT)further confirms the enhanced Mg^(2+)storage kinetics during such multi-electron involved electrochemical reaction process.Such discovery provides new insights into the designing of multi-electron reaction process in cathode as well as neutralizing structural change during such reaction for realizing superior electrochemical performance in energy storage devices. 展开更多
关键词 Multi-electron reaction W doping stable structure CATHODE Rechargeable magnesium batteries
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Coal-rock gas:Concept,connotation and classification criteria
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作者 LI Guoxin ZHANG Shuichang +11 位作者 HE Haiqing HE Xinxing ZHAO Zhe NIU Xiaobing XIONG Xianyue ZHAO Qun GUO Xujie HOU Yuting ZHANG Lei LIANG Kun DUAN Xiaowen ZHAO Zhenyu 《Petroleum Exploration and Development》 SCIE 2024年第4期897-911,共15页
In recent years,great breakthroughs have been made in the exploration and development of natural gas in deep coal-rock reservoirs in Junggar,Ordos and other basins in China.In view of the inconsistency between the ind... In recent years,great breakthroughs have been made in the exploration and development of natural gas in deep coal-rock reservoirs in Junggar,Ordos and other basins in China.In view of the inconsistency between the industrial and academic circles on this new type of unconventional natural gas,this paper defines the concept of"coal-rock gas"on the basis of previous studies,and systematically analyzes its characteristics of occurrence state,transport and storage form,differential accumulation,and development law.Coal-rock gas,geologically unlike coalbed methane in the traditional sense,occurs in both free and adsorbed states,with free state in abundance.It is generated and stored in the same set of rocks through short distance migration,occasionally with the accumulation from other sources.Moreover,coal rock develops cleat fractures,and the free gas accumulates differentially.The coal-rock gas reservoirs deeper than 2000 m are high in pressure,temperature,gas content,gas saturation,and free-gas content.In terms of development,similar to shale gas and tight gas,coal-rock gas can be exploited by natural formation energy after the reservoirs connectivity is improved artificially,that is,the adsorbed gas is desorbed due to pressure drop after the high-potential free gas is recovered,so that the free gas and adsorbed gas are produced in succession for a long term without water drainage for pressure drop.According to buried depth,coal rank,pressure coefficient,reserves scale,reserves abundance and gas well production,the classification criteria and reserves/resources estimation method of coal-rock gas are presented.It is preliminarily estimated that the coal-rock gas in place deeper than 2000 m in China exceeds 30×10^(12)m^(3),indicating an important strategic resource for the country.The Ordos,Sichuan,Junggar and Bohai Bay basins are favorable areas for large-scale enrichment of coal-rock gas.The paper summarizes the technical and management challenges and points out the research directions,laying a foundation for the management,exploration,and development of coal-rock gas in China. 展开更多
关键词 coal-rock gas coalbed methane adsorbed gas free gas classification criteria reserves estimation method
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Effects of thinning and understory removal on water use efficiency of Pinus massoniana:evidence from photosynthetic capacity and stable carbon isotope analyses
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作者 Ting Wang Qing Xu +4 位作者 Beibei Zhang Deqiang Gao Ying Zhang Jing Jiang Haijun Zuo 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期42-53,共12页
Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate change.However,the effects of thinning and understory removal on WUE and... Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate change.However,the effects of thinning and understory removal on WUE and its key controlling processes are not well understood,which limits our comprehension of the physiological mechanisms of various management practices.In this study,four forest management measures(no thinning:NT;understory removal:UR;light thinning:LT;and heavy thinning:HT)were carried out in Pinus massoniana plantations in a subtropical region of China.Photosynthetic capacity and needle stable carbon isotope composition(δ^(13)C)were measured to assess instantaneous water use efficiency(WUE_(inst))and long-term water use efficiency(WUE_(i)).Multiple regression models and structural equation modelling(SEM)identified the effects of soil properties and physiological performances on WUE_(inst)and WUE_(i).The results show that WUE_(inst)values among the four treatments were insignificant.However,compared with the NT stand(35.8μmol·mol^(-1)),WUE_(i)values significantly increased to 41.7μmol·mol^(-1)in the UR,50.1μmol·mol^(-1)in the LT and 46.6μmol·mol^(-1)in HT treatments,largely explained by photosynthetic capacity and soil water content.Understory removal did not change physiological performance(needle water potential and photosynthetic capacity).Thinning increased the net photosynthetic rate(A_n)but not stomatal conductance(g_s)or predawn needle water potential(ψ_(pd)),implying that the improvement in water use efficiency for thinned stands was largely driven by radiation interception than by soil water availability.In general,thinning may be an appropriate management measure to promote P.massoniana WUE to cope with seasonal droughts under future extreme climates. 展开更多
关键词 stable carbon isotope Water use efficiency THINNING Understory removal Photosynthetic capacity Needle water potential
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Variation characteristics of stable isotopes in atmospheric precipitation in Adelaide,Australia
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作者 WANG Dizhou ZHANG Xinping +2 位作者 LIU Zhongli LI Guang GUAN Huade 《地球环境学报》 CSCD 2024年第4期641-652,共12页
Background,aim,and scope Stable isotope in water could respond sensitively to the variation of environment and be reserved in different geological archives,although they are scarce in the environment.And the methods d... Background,aim,and scope Stable isotope in water could respond sensitively to the variation of environment and be reserved in different geological archives,although they are scarce in the environment.And the methods derived from the stable isotope composition of water have been widely applied in researches on hydrometeorology,weather diagnosis,and paleoclimate reconstruction,which help well for understanding the water-cycle processes in one region.Here,it is aimed to explore the temporal changes of stable isotopes in precipitation from Adelaide,Australia and determine the influencing factors at different timescales.Materials and methods Based on the isotopic data of daily precipitation over four years collected in Adelaide,Australia,the variation characteristics of dailyδD,δ^(18)O,and dexcess in precipitation and its relationship with meteorological elements were analyzed.Results The results demonstrated the local meteoric water line(LMWL)in Adelaide,wasδD=6.38×δ^(18)O+6.68,with a gradient less than 8.There is a significant negative correlation between dailyδ^(18)O and precipitation amount or relative humidity at daily timescales in both the whole year and wither/summerhalf year(p<0.001),but a significant positive correlation between dailyδ^(18)O and temperature in the whole year and the winter half-year(p<0.001).Discussion The correlation coefficients betweenδ^(18)O and daily mean temperature didn’t show a significant positive correlation,which may be attributed to that the precipitation in Adelaide area in January was mainly influenced by strong convective weather,and the stable isotope values in precipitation were significantly negative.Furthermore,this propose was also evidenced by the results from dexcess of precipitation with larger value in the winter half-year than that in the summer half-year,which may be resulted from the precipitation events in winter are mostly influenced by oceanic water vapor,while the sources of water vapor in summer precipitation events are more complicated and influenced by strong convective weather.On the other hand,the slope and intercept of theδ^(18)O—P regression lines in the summer months(-0.41 and 0.50‰)are larger and smaller than those in the winter months(-0.22 and-2.15‰),respectively,indicating that the precipitation stable isotopes have a relatively stronger rainout effect in the summer months than in the winter months.Besides,the measured values ofδ^(18)O in daily precipitation have a good linear relationship with our simulated values ofδ^(18)O,demonstrating the established regression model could provide a reliable simulation for theδ^(18)O values in daily precipitation in Adelaide area.It’s worth noting that the precipitation events with low precipitation amount,low relative humidity and high temperature,usually had relatively small slope and intercept of MWL,implying that raindrops may be strongly affected by sub-cloud secondary evaporation in the falling process.Conclusions The variation ofδ^(18)O in daily precipitation from Adelaide region was controlled by different factors at different timescales.And the water vapor sources and the meteorological conditions of precipitation events(such as the degree of sub-cloud secondary evaporation)also played an important role on the variation ofδ^(18)O.Recommendations and perspectives Stable isotope in daily precipitation can provide more accurate information about water-cycle and atmosphere circulation,it is therefore necessary to continue to collect and analyze daily-scale precipitation data over a longer time span.The results of this study will provide the basis for the fields of hydrometeorology,meteorological diagnosis and paleoclimate reconstruction in Adelaide,Australia. 展开更多
关键词 Adelaide PRECIPITATION stable isotopes meteoric water line stepwise regression analysis
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Quantification of irrigation water transport processes in ZiZiphus jujuba garden using water stable isotopes
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作者 ZHONG Xiaofei ZHANG Mingjun +3 位作者 CHE Cunwei LIU Zechen LI Beibei ZHANG Yuanyuan 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3263-3274,共12页
ZiZiphus jujuba,which is native to China,has become one of the main crops widely planted in the western Loess Plateau because of its drought and flood-tolerance,adaptability,and higher nutritional value of the fruit.T... ZiZiphus jujuba,which is native to China,has become one of the main crops widely planted in the western Loess Plateau because of its drought and flood-tolerance,adaptability,and higher nutritional value of the fruit.The irrigation water infiltration in Z.jujuba gardens is complex,and understanding its mechanisms is essential for efficient water use and sustainable agriculture.This knowledge helps ensure the long-term success of jujuba cultivation.This paper describes a field experiment that investigates the infiltration process of irrigation water from Z.jujuba garden and quantifies the contribution of irrigation water to soil water at different depths using the MixSIAR model.According to the FC(Field water holding Capacity)of Z.jujuba,irrigation experiments with three volumes of 80%FC,60%FC,and 40%FC are set up in this study.The study finds that water retention is better in Z.jujuba garden soils with a higher proportion of coarse gravel in the soil particle composition.Soil water content exhibits a gradient change after irrigation,with deeper wetting front transport depth observed with increased irrigation water.Additionally,there is correlation between soil temperature and soil water content.The soil water in Z.jujuba garden generally exhibits a preferential flow signal in the 0-40 cm range.Below 40 cm,a piston flow pattern dominates.The rate of soil water infiltration increases with the amount of irrigation water.In the 0-40 cm range of the soil vertical profile,irrigation water was the main contributor to soil water.Z.jujuba demonstrated flexibility in water uptake,primarily absorbing soil water at depths of 0-40 cm.For optimal growth of Z.jujuba at this stage,40%FC irrigation is recommended.The results are expected to be valuable future irrigation practices and land use planning for Z.jujuba garden in arid zones,supporting sustainable agricultural development and water management. 展开更多
关键词 Water stable isotopes Different irrigation volumes ZiZiphus jujuba Irrigation water infiltration process MixSIAR model
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Evaluation of AVNRT & AVRT by Different Criteria: Old & New
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作者 Abdul Hamid Tahmina Alam Sonali +3 位作者 Rizwan Rehan Pijous Biswas Subas Caandro Datta Asif Zaman 《World Journal of Cardiovascular Surgery》 2024年第7期95-106,共12页
The two most frequent causes of paroxysmal SVT are atrioventricular tachycardia (AVRT) and atrioventricular nodal re-entrant tachycardia (AVNRT). The purpose of this study was to assess the diagnostic efficacy of trad... The two most frequent causes of paroxysmal SVT are atrioventricular tachycardia (AVRT) and atrioventricular nodal re-entrant tachycardia (AVNRT). The purpose of this study was to assess the diagnostic efficacy of traditional and newly proposed ECG criteria in the identification of Avnrt and Avrt. Aim of the Study: The aim of this study was to evaluate Atrioventricular Nodal Reentrant Tachycardia (AVNRT) and Atrioventricular Re-entrant Tachycardia (AVRT) using both traditional and novel criteria. Methods: This prospective observational study was conducted at the Electrophysiology Unit, Department of Cardiology, National Institute of Cardiovascular Diseases (NICVD) in Dhaka, from February 2019 to January 2020. A total of 62 patients with Supraventricular Tachycardia (SVT) undergoing electrophysiology study (EPS) were included. Standard ECG criteria were applied for the differential diagnosis, and electrophysiological diagnoses were made using established criteria. Statistical analysis, including descriptive statistics and appropriate tests, was performed using SPSS 23.0. Result: In our study of 62 patients with Supraventricular Tachycardia (SVT), we found that 66.1% had AVNRT and 33.9% had AVRT. The mean age in AVNRT was higher than AVRT (41.3 ± 9.7 vs. 38.5 ± 14.3, p = 0.36) with statistically no significant difference, with similar gender distribution between AVNRT and AVRT groups. Classical AVNRT criteria were present in 30.6% of patients, and 45.2% showed a Pseudo R' wave in aVR. Additionally, 30.6% had an RP interval ≥100ms, more prevalent in AVRT patients (66.7%). Conclusion: Integrating traditional and novel criteria, including lead aVR analysis, enhances the electrocardiographic diagnosis of AVNRT and AVRT, offering a pathway to refined patient care. 展开更多
关键词 SVT (Supraventricular Tachycardia) AVNRT (Atrioventricular Nodal Re-Entrant Tachycardia) AVRT (Atrioventricular Re-Entrant Tachycardia) ECG criteria Electrophysiology
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Synergistic enhancement of cathode/anode interfaces with high water-retentive organohydrogel enabling highly stable zinc ion batteries
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作者 Xixi Zhang Qingxiu Yu +8 位作者 Guangmeng Qu Xiaoke Wang Chuanlin Li Chenggang Wang Na Li Jinzhao Huang Cuiping Han Hongfei Li Xijin Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期670-679,共10页
Current aqueous battery electrolytes,including conve ntional hydrogel electrolytes,exhibit unsatisfactory water retention capabilities.The sustained water loss will lead to subsequent polarization and increased intern... Current aqueous battery electrolytes,including conve ntional hydrogel electrolytes,exhibit unsatisfactory water retention capabilities.The sustained water loss will lead to subsequent polarization and increased internal resistance,ultimately resulting in battery failure.Herein,a double network(DN) orga no hydrogel electrolyte based on dimethyl sulfoxide(DMSO)/H_(2)O binary solvent was proposed.Through directionally reconstructing hydrogen bonds and reducing active H_(2)O molecules,the water retention ability and cathode/anode interfaces were synergistic enhanced.As a result,the synthesized DN organohydrogel demonstrates exceptional water retention capabilities,retaining approximately 75% of its original weight even after the exposure to air for 20 days.The Zn MnO_(2) battery delivers an outstanding specific capacity of275 mA h g^(-1) at 1 C,impressive rate performance with 85 mA h g^(-1) at 30 C,and excellent cyclic stability(95% retention after 6000 cycles at 5 C).Zn‖Zn symmetric battery can cycle more than 5000 h at 1 mA cm^(-2) and 1 mA h cm^(-2) without short circuiting.This study will encourage the further development of functional organohydrogel electrolytes for advanced energy storage devices. 展开更多
关键词 Enhanced water-retentive Organohydrogel electrolyte stable Zn||MnO+2 batteries Enhancement of cathode/anode interfaces
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AI绘画在艺术创作中的应用——以Stable Diffusion为例
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作者 李深森 《现代信息科技》 2024年第8期133-137,共5页
AI绘画是基于人工智能技术进行艺术创作的一种方法,在AI绘画中,Stable Diffusion可提供稳定、连续和高质量的图像生成。Stable Diffusion是一种基于生成对抗网络的图像生成方法,它通过不断更新图像的噪声分布,逐渐生成越来越逼真的图像... AI绘画是基于人工智能技术进行艺术创作的一种方法,在AI绘画中,Stable Diffusion可提供稳定、连续和高质量的图像生成。Stable Diffusion是一种基于生成对抗网络的图像生成方法,它通过不断更新图像的噪声分布,逐渐生成越来越逼真的图像。在绘画艺术创作中,Stable Diffusion能够激发创作者的灵感,帮助他们探索不同的创作风格和创作方式。与此同时,创作者仍需运用自己的审美判断力对所绘制的作品进行筛选和调整。 展开更多
关键词 AI绘画 stable Diffusion 艺术创作
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