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An Expert Judgment-based Prediction Tool for Developmental and R eproductive Toxicity(DART)
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作者 LI Kangning ZHENG Yuting +7 位作者 Jane ROSE WU Shengde LI Bin Vatsal MEHTA Ashley MUDD George DASTON YU Yang WANG Ying 《生态毒理学报》 北大核心 2025年第2期77-91,共15页
Developmental and reproductive toxicity(DART)endpoint entails a toxicological assessment of all developmental stages and reproductive cycles of an organism.In silico tools to predict DART will provide a method to asse... Developmental and reproductive toxicity(DART)endpoint entails a toxicological assessment of all developmental stages and reproductive cycles of an organism.In silico tools to predict DART will provide a method to assess this complex toxicity endpoint and will be valuable for screening emerging pollutants as well as for m anaging new chemicals in China.Currently,there are few published DART prediction models in China,but many related research and development projects are in progress.In 2013,WU et al.published an expert rule-based DART decision tree(DT).This DT relies on known chemical structures linked to DART to forecast DART potential of a given chemical.Within this procedure,an accurate DART data interpretation is the foundation of building and expanding the DT.This paper excerpted case studies demonstrating DART data curation and interpretation of four chemicals(including 8-hydroxyquinoline,3,5,6-trichloro-2-pyridinol,thiacloprid,and imidacloprid)to expand the existing DART DT.Chemicals were first selected from the database of Solid Waste and Chemicals Management Center,Ministry of Ecology and Environment(MEESCC)in China.The structures of these 4 chemicals were analyzed and preliminarily grouped by chemists based on core structural features,functional groups,receptor binding property,metabolism,and possible mode of actions.Then,the DART conclusion was derived by collecting chemical information,searching,integrating,and interpreting DART data by the toxicologists.Finally,these chemicals were classified into either an existing category or a new category via integrating their chemical features,DART conclusions,and biological properties.The results showed that 8-hydroxyquinoline impacted estrous cyclicity,s exual organ weights,and embryonal development,and 3,5,6-trichloro-2-pyridinol caused central nervous system(CNS)malformations,which were added to an existing subcategory 8e(aromatic compounds with multi-halogen and nitro groups)of the DT.Thiacloprid caused dystocia and fetal skeletal malformation,and imidacloprid disrupted the endocrine system and male fertility.They both contain 2-chloro-5-methylpyridine substituted imidazolidine c yclic ring,which were expected to create a new category of neonicotinoids.The current work delineates a t ransparent process of curating toxicological data for the purpose of DART data interpretation.In the presence of sufficient related structures and DART data,the DT can be expanded by iteratively adding chemicals within the a pplicable domain of each category or subcategory.This DT can potentially serve as a tool for screening emerging pollutants and assessing new chemicals in China. 展开更多
关键词 developmental and reproductive toxicity decision tree prediction tool expert judgment new chemical management
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Morphological characteristics,developmental dynamics,and gene temporal expressions across various development stages of Aphis gossypii sexual female
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作者 LÜJingli WANG Liuyu +10 位作者 ZHANG Kaixin LI Dongyang GAO Mengxue GUO Lixiang TANG Zhijuan GAO Xueke ZHU Xiangzhen WANG Li JI Jichao LUO Junyu CUI Jinjie 《Journal of Cotton Research》 CAS 2024年第4期372-385,共14页
Background Aphis gossypii(Hemiptera:Aphididae)is a worldwide polyphagous phloem-feeding agricultural pest,and it can produce offspring by sexual or asexual reproduction.Compared with dozens of generations by parthenog... Background Aphis gossypii(Hemiptera:Aphididae)is a worldwide polyphagous phloem-feeding agricultural pest,and it can produce offspring by sexual or asexual reproduction.Compared with dozens of generations by parthenogenesis,sexual reproduction is performed in only one generation within one year,and little is known about the sexual reproduction of A.gossypii.In this study,sexual females of A.gossypii were successfully obtained through a previously established induction platform,and the morphological characteristics,developmental dynamics,and temporal gene expression were examined.Subsequently,signaling pathways potentially involved in regulating the growth,development,and reproduction of sexual females were investigated.Results The morphological observation showed that from the 1st instar nymph to adult,sexual females exhibited a gradually deepened body color,an enlarged body size,longer antennae with a blackened end,and obviously protruding cauda(in adulthood).The anatomy found that the ovaries of sexual females developed rapidly from the 2^(nd)instar nymph,and the embedded oocytes matured in adulthood.In addition,time-course transcriptome analysis revealed that gene expression profiles across the development of sexual females fell into 9 clusters with distinct patterns,in which gene expression levels in clusters 1,5,and 8 peaked at the 2^(nd)instar nymphal stage with the largest number of up-regulated genes,suggesting that the 2^(nd)instar nymph was an important ovary development period.Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis revealed that a large number of genes in the sexual female adult were enriched in the TGF-beta signaling pathway and Forkhead box O(FoxO)signaling pathway,highlighting their important role in sexual female adult development and reproduction.Conclusion The morphological changes of the sexual female at each developmental stage were revealed for the first time.In addition,time-course transcriptomic analyses suggest genes enriched in the TGF-beta signaling pathway and FoxO signaling pathway probably contribute to regulating the development and oocyte maturation of sexual females.Overall,these findings will facilitate the regulating mechanism research in the growth and development of sexual females by providing candidate genes. 展开更多
关键词 Aphis gossypii Sexual female Growth and development OOGENESIS Time-course transcriptome
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Future China-Africa research collaboration in geoscience:Challenges and opportunities
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作者 Michael H.STEPHENSON Hassina MOURI +5 位作者 Gbenga OKUNLOLA CHENG Li WANG Meng ZHAO Yu GU Liping WANG Chengshan 《地学前缘》 北大核心 2025年第1期459-465,共7页
At the 19th G20 Summit in Brazil in November 2024,China promoted the development of sustainable solutions to climate change,biodiversity loss,and environmental pollution.This continued the theme of the 2016 G20 Hangzh... At the 19th G20 Summit in Brazil in November 2024,China promoted the development of sustainable solutions to climate change,biodiversity loss,and environmental pollution.This continued the theme of the 2016 G20 Hangzhou Summit,at which China placed development at the center of the G20’s macroeconomic policy coordination for the first time,adopting the G20 Action Plan on the United Nations 2030 Agenda for Sustainable Development and the G20 Initiative on Supporting Industrialization in Africa and Least Developed Countries.In Brazil,China announced actions on advancing modernization in Africa over the next three years with a Chinese commitment of RMB360 billion yuan in financial support.In this article,we examine the potential role of geoscience research and practice in development,particularly in the sustainable use of natural resources,the prevention of climate change impacts,as well as mitigation of geo-hazards and their health implications,indicating the areas where China’s geoscience for Africa is strong and where it requires more effort.We find that although China is the world’s leading publisher of scientific papers,its contribution to geoscience in Africa(the globe’s fastest-growing economic area),as shown by bibliometric research,appears to be rather small and inconsistent with the research priorities of Africa.Amongst the priorities for geoscience research in Africa,which are not addressed substantially by the research conducted so far,are sustainable mineral and hydrocarbon development,hydrology and hydrogeology,climate change and resilience,natural hazards,medical geology,agrominerals,and geoscience education and training.A particular opportunity for African nations is the presence of critical minerals-minerals needed for the energy transition and for batteries for electric cars in particular.Africa is well-endowed with many of these critical materials,such as rare earth elements and platinum group metals.Several research groups stress the need for the agency on the part of African institutions to map out these valuable resources,understand their value and the economics and sustainability of their extraction,encourage local business,attract investment,and scrutinize proposals from potential international investors to get the best deals.A strong point of existing China-led geoscience development includes the Deep-time Digital Earth(DDE)program online computing platform and its artificial intelligence tool GeoGPT,which is being developed in partnership with Zhejiang Laboratory.These are being developed with strong China funding support for free and wide global access,with a particular focus on Africa.These advanced tools will help to place the agency of development squarely in the hands of African scientists and institutions.In summary,the following are recommended:(1)a more coordinated and strategic approach to China-led geoscience research in Africa;(2)an Africa-centered,geoscience funding initiative that concentrates on relevant topics to the continent such as critical minerals exploration and other geological resources,materials and processes and their health implications on the populations and ecosystems in general,as well as climate change and climate change resilience;and(3)continued support for China-led international initiatives that seek to increase the agency and capacity of Africa geoscience researchers,for example the Deep-time Digital Earth platform. 展开更多
关键词 open science sustainable development digital empowerment China-Africa geo-collaboration Deep-Time Digital Earth
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N^(6)-methyladenosine modification and skin diseases
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作者 JIANG Ling HU Yibo CHEN Jing 《中南大学学报(医学版)》 北大核心 2025年第3期382-395,共14页
Currently,research on N^(6)-methyladenine(m^(6)A)is extensive in the field of oncology,while studies involving m^(6)A and skin diseases remain relatively limited.Based on existing reports,we searched PubMed and Web of... Currently,research on N^(6)-methyladenine(m^(6)A)is extensive in the field of oncology,while studies involving m^(6)A and skin diseases remain relatively limited.Based on existing reports,we searched PubMed and Web of Science for literature related to m^(6)A and dermatological conditions.Analysis of citation counts and journal impact factors revealed a significant upward trend in the volume of m^(6)A-related research.Term frequency analysis of titles and abstracts indicated that studies mainly focus on skin tumors and inflammatory or immune-related skin diseases,particularly melanoma,psoriasis,and skin development.Transcriptomic data from the Gene Expression Omnibus(GEO)were analyzed,revealing differential expression of m^(6)A-related genes in 4 types of skin tumors(including squamous cell carcinoma and basal cell carcinoma)as well as in inflammatory skin diseases such as psoriasis and atopic dermatitis,and potential mechanisms of action were also explored.Findings suggest that m^(6)A modifications exhibit heterogeneity between neoplastic and nonneoplastic skin diseases.However,the regulatory mechanisms of m^(6)A dynamic modifications on key genes involved in dermatological disorders remain unclear and warrant further investigation. 展开更多
关键词 skin tumors inflammatory and immune-related skin diseases N^(6)-methyladenosine EPIGENETICS drug development
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Mechanical properties and damage evolution law of cemented-gangue-fly-ash backfill modified with different contents of recycled steel fibers
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作者 CHE Chi-yuan CAO Sheng-gen +5 位作者 ZHANG Yun LIU Yang ZHAO Chang-zheng DU Shu-yu LI Jiang SHAN Chang-hao 《Journal of Central South University》 2025年第7期2661-2678,共18页
The cemented-gangue-fly-ash backfill(CGFB)prepared from coal-based solid waste materials commonly exhibits high brittleness,leading to an increased susceptibility to cracking.Uniaxial compressive strength(UCS),acousti... The cemented-gangue-fly-ash backfill(CGFB)prepared from coal-based solid waste materials commonly exhibits high brittleness,leading to an increased susceptibility to cracking.Uniaxial compressive strength(UCS),acoustic emission(AE),and scanning electron microscopy tests were conducted on CGFB samples with recycled steel fiber(RSF)contents of 0,0.5%,1.0%and 1.5%to assess the mechanical properties and damage evolution law of the CGFB.The research findings indicate that:1)When RSF contents were 0.5%,1%,and 1.5%,respectively,compared to samples without RSF,the UCS decreased by 3.86%,6.76%,and 15.59%,while toughness increased by 69%,98%,and 123%;2)The addition of RSFs reduced the post-peak stress energy activity and increased the fluctuations in the b-value;3)As the RSF dosage increased from 0 to 1.5%,the per unit dissipated strain energy increased from 5.84 to 21.51,and the post-peak released energy increased from 15.07 to 33.76,indicating that the external energy required for the CGFB sample to fail increased;4)The hydration products,such as C-S-H gel,ettringite,and micro-particle materials,were embedded in the damaged areas of the RSFs,increasing the frictional force at the interface between the RSF and CGFB matrix.The shape variability of the RSFs caused interlocking between the RSFs and the matrix.Both mechanisms strengthened the bridging effect of the RSFs in the CGFB,thereby improving the damage resistance capability of CGFB.The excellent damage resistance occurred at an RSF content of 0.5%;thus,this content is recommended for engineering applications. 展开更多
关键词 recycled steel fibers cemented-gangue-fly-ash backfill acoustic emission crack development energy evolution
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EOD模式下海洋生态保护项目建设的法律问题研究
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作者 岳昕宸 周连义 +1 位作者 徐福源 刘盈 《河北渔业》 2025年第10期63-67,共5页
海洋强国建设是加快推进中国式现代化的有机组成部分和重要战略任务。随着生态文明建设深入推进,生态环境导向开发(Ecology-Oriented Development,EOD)模式作为一种创新性的项目组织实施方式,以“两山”理论为基础,为海洋生态保护与区... 海洋强国建设是加快推进中国式现代化的有机组成部分和重要战略任务。随着生态文明建设深入推进,生态环境导向开发(Ecology-Oriented Development,EOD)模式作为一种创新性的项目组织实施方式,以“两山”理论为基础,为海洋生态保护与区域经济协同发展提供了重要路径。基于我国EOD政策演变与实践探索,通过梳理与EOD海洋生态保护项目建设的相关法律法规,在现有研究成果的基础之上,指出项目实施过程中可能存在的法律问题,具体包括项目合规性问题、项目参与主体边界与责任不清等,并对此提出针对性建议,通过增设“复合用海”类型、完善海洋生态保护红线相关法规、严格准入机制以及制定专门的EOD海洋生态保护项目管理办法,为EOD海洋生态保护项目建设与可持续发展提供法治保障。 展开更多
关键词 生态环境导向开发(Ecology-Oriented Development EOD) 海洋生态保护 法治
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Nutritional Composition and Distribution of Heracleum dissectum Ledeb.at Different Growth Stages
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作者 Pan Yan Fan Lili +4 位作者 Sun Yan Li Sining Zhuang Yue Sun Haixia Zhong Rongzhen 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第3期20-32,共13页
Heracleum dissectum Ledeb.(HD)with high edible and medicinal values is distributed in Northeast Asia.To provide a reference for selecting appropriate parts and periods to harvest HD,the nutrient contents in different ... Heracleum dissectum Ledeb.(HD)with high edible and medicinal values is distributed in Northeast Asia.To provide a reference for selecting appropriate parts and periods to harvest HD,the nutrient contents in different parts of HD at three growth stages were determined.The nutrients being determined are essential nutrients closely related to human needs,and the crude protein content of HD was 3.58‒28.43 g•100 g^(-1)DW(dry weight),sugar content was 2.33‒30.92 g•100 g^(-1)DW,and soluble dietary fiber content was 9.71‒26.09 g•100 g^(-1)DW.Crude protein was mainly distributed in leaf blades and inflorescences,sugar was primarily found in roots,and dietary fiber was predominantly located in leaves.From the leaf development stage to the flowering stage and then to the late seed harvest stage,the content of moisture,crude protein and soluble sugar first decreased and then increased.In contrast,the content of dietary fiber and crude fat first increased and then decreased. 展开更多
关键词 nutrient content VEGETABLE plant organ developmental stage
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An Effective 3D-CFD Methodology for the Complementary Virtual Development of Alternative Fuels and Engine Concepts
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作者 Robin SCHMELCHER Thomas GAL +6 位作者 Mario PIPOLO Cristian TORTORELLA Antonino VACCA Edoardo ROSSI Francesco CUPO Marco CHIODI AndréCASAL KULZER 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第S01期1-8,共8页
With the aim of reducing the cost of developing internal combustion engines,while at the same time investigating different geometries,layouts and fuels,3D-CFD-CHT simulations represent an indispensable part for the de... With the aim of reducing the cost of developing internal combustion engines,while at the same time investigating different geometries,layouts and fuels,3D-CFD-CHT simulations represent an indispensable part for the development of new technologies.These tools are increasingly used by manufacturers,as a screening process before building the first prototype.This paper presents an innovative methodology for virtual engine development.The 3D-CFD tool QuickSim,developed at FKFS,allows both a significant reduction in computation time and an extension of the simulated domain for complete engine systems.This is possible thanks to a combination of coarse meshes and self-developed internal combustion engine models,which simultaneously ensure high predictability.The present work demonstrates the capabilities of this innovative methodology for the design and optimization of different engines and fuels with the goal of achieving the highest possible combustion efficiencies and pollutant reductions.The analysis focuses on the influence of different fuels such as hydrogen,methanol,synthetic gasolines and methane on different engine geometries,in combination with suitable injection and ignition systems,including passive and active pre-chambers.Lean operations as well as knock reduction are discussed,particularly for methane and hydrogen injection.Finally,it is shown how depending on the chosen fuel,an appropriate ad-hoc engine layout can be designed to increase the indicated efficiency of the respective engines. 展开更多
关键词 eFuels METHANE METHANOL hydrogen CO_(2)reduction virtual development 3D-CFD
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Comparative analysis of SIMILAR to RCD ONE(SRO)family from tetraploid cotton species and their diploid progenitors depict their significance in cotton growth and development
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作者 SHABAN Muhammad TABASSUM Riaz +5 位作者 RANA Iqrar Ahmad ATIF Rana Muhammad AZMAT Muhammad Abubakkar IQBAL Zubair MAJEED Sajid AZHAR Muhammad Tehseen 《Journal of Cotton Research》 CAS 2024年第1期45-57,共13页
Background SRO(Similar to RCD1)genes family is largely recognized for their importance in the growth,develop-ment,and in responding to environmental stresses.However,genome-wide identification and functional character... Background SRO(Similar to RCD1)genes family is largely recognized for their importance in the growth,develop-ment,and in responding to environmental stresses.However,genome-wide identification and functional characteri-zation of SRO genes from cotton species have not been reported so far.Results A total of 36 SRO genes were identified from four cotton species.Phylogenetic analysis divided these genes into three groups with distinct structure.Syntenic and chromosomal distribution analysis indicated uneven distribu-tion of GaSRO,GrSRO,GhSRO,and GbSRO genes on A2,D5 genomes,Gh-At,Gh-Dt,Gb-At,and Gb-Dt subgenomes,respectively.Gene duplication analysis revealed the presence of six duplicated gene pairs among GhSRO genes.In promoter analysis,several elements responsive to the growth,development and hormones were found in GhSRO genes,implying gene induction during cotton growth and development.Several miRNAs responsive to plant growth and abiotic stress were predicted to target 12 GhSRO genes.Organ-specific expression profiling demonstrated the roles of GhSRO genes in one or more tissues.In addition,specific expression pattern of some GhSRO genes dur-ing ovule development depicted their involvement in these developmental processes.Conclusion The data presented in this report laid a foundation for understanding the classification and functions of SRO genes in cotton. 展开更多
关键词 COTTON SRO MIRNAS Gene duplications Gene expression Ovule development
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Morphological and cytological assessments reveal pollen degradation causes pollen abortion in cotton cytoplasmic male sterility lines
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作者 PEI Qingyu LIU Jinshan +10 位作者 GUO Chunping MA Xiaomei LIU Xiaoyan YOU Chunyuan LIN Hairong LI Zhibo ZHAO Ruihai ZHU Bo WU Yuanlong PAN Zhenyuan NIE Xinhui 《Journal of Cotton Research》 CAS 2024年第3期266-276,共11页
Background Understanding the mechanism of male sterility is crucial for producing hybrid seeds and developing sterile germplasm resources.However,only a few cytoplasmic male sterility(CMS)lines of cotton have been pro... Background Understanding the mechanism of male sterility is crucial for producing hybrid seeds and developing sterile germplasm resources.However,only a few cytoplasmic male sterility(CMS)lines of cotton have been produced due to several challenges,like inadequate variation of agronomic traits,incomplete sterility,weak resilience of restorer lines,and difficulty in combining strong dominance.Therefore,the morphological and cytological identification of CMS in cotton will facilitate hybrid breeding.Results Two F_(2) segregating populations of cotton were constructed from cytoplasmic male sterile lines(HaA and 01A,maternal)and restorer lines(HaR and 26R,paternal).Genetic analysis of these populations revealed a segregation ratio of 3:1 for fertile to sterile plants.Phenotypic analysis indicated no significant differences in traits of flower bud development between sterile and fertile plants.However,sterile plants exhibited smaller floral organs,shortened filament lengths,and anther atrophy on the flowering day in comparison with the fertile plants.When performed scanning electron microscopy(SEM),the two F_(2) populations revealed morphological variations in the anther epidermis.Cellular analysis showed no significant differences in pollen development before pollen maturation.Interestingly,between the pollen maturation and flowering stages,the tapetum layer of sterile plants degenerated prematurely,resulting in abnormal pollen grains and gradual pollen degradation.Conclusion The results of this study suggest that fertility-restoring genes are controlled by a single dominant gene.Sterile plants exhibit distinctive floral morphology,which is characterized by stamen atrophy and abnormal anthers.Pollen abortion occurs between pollen maturity and flowering,indicating that premature tapetum degradation may be the primary cause of pollen abortion.Overall,our study provides a theoretical basis for utilizing CMS in hybrid breeding and in-depth investigation of the dominant configuration of cotton hybrid combinations,mechanisms of sterility,and the role of sterile and restorer genes. 展开更多
关键词 COTTON Cytoplasmic male sterility Genetic analysis Morphological characteristics Pollen development
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Networking Observation and Applications of Chinese Ocean Satellites
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作者 ZOU Bin LIU Yuxin 《空间科学学报》 CAS CSCD 北大核心 2024年第4期722-730,共9页
This paper presents the networking observation capabilities of Chinese ocean satellites and their diverse applications in ocean disaster prevention,ecological monitoring,and resource development.Since the inaugural la... This paper presents the networking observation capabilities of Chinese ocean satellites and their diverse applications in ocean disaster prevention,ecological monitoring,and resource development.Since the inaugural launch in 2002,China has achieved substantial advancements in ocean satellite technology,forming an observation system composed of the HY-1,HY-2,and HY-3 series satellites.These satellites are integral to global ocean environmental monitoring due to their high resolution,extensive coverage,and frequent observations.Looking forward,China aims to further enhance and expand its ocean satellite capabilities through ongoing projects to support global environmental protection and sustainable development. 展开更多
关键词 Chinese ocean satellites Networking observation Ocean forecasting Ocean disaster prevention and mitigation Ocean ecological monitoring Ocean resource development Polar monitoring Terrestrial applications
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DEVELOPMENT AND ERROR ANALYSIS OF AN INSPECTING SYSTEM FOR MEASURING THE ROTATIONAL INERTIA OF BULLETS 被引量:15
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作者 车英 李占国 +3 位作者 陈礼华 白素平 马宏 韩文波 《兵工学报》 EI CAS CSCD 北大核心 2000年第1期-,共3页
介绍了一种用于测量弹丸转动惯量的高精度测量仪器,该仪器利用双悬丝扭摆机构、光电计时系统提取摆动周期信息,由MCS-51系列单片机组成的测量系统进行数据处理,并由LED显示器测量结果。文中阐述了仪器的工作原理, 推导了所需的计算... 介绍了一种用于测量弹丸转动惯量的高精度测量仪器,该仪器利用双悬丝扭摆机构、光电计时系统提取摆动周期信息,由MCS-51系列单片机组成的测量系统进行数据处理,并由LED显示器测量结果。文中阐述了仪器的工作原理, 推导了所需的计算公式,分析了产生测量误差的因素,进行了定量精度分析,给出了实验结果与测量精度。 展开更多
关键词 转动惯量 摆动周期 测量误差 DEVELOPMENT AND ERROR ANALYSIS OF AN INSPECTING
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网格环境中信任-激励相容的资源分配机制 被引量:12
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作者 张煜 林莉 +2 位作者 怀进鹏 李先贤 钟亮 《软件学报》 EI CSCD 北大核心 2006年第11期2245-2254,共10页
在网格环境中,多数节点希望能够更多地使用其他节点的资源,而不愿共享本地的资源.每个理性的用户在追求自身利益最大化的同时,严重影响了协作整体的运行效率.在实际应用中,要吸引资源的拥有者加入资源协作,就必须保证其利益和安全.讨论... 在网格环境中,多数节点希望能够更多地使用其他节点的资源,而不愿共享本地的资源.每个理性的用户在追求自身利益最大化的同时,严重影响了协作整体的运行效率.在实际应用中,要吸引资源的拥有者加入资源协作,就必须保证其利益和安全.讨论了资源激励机制和分配机制之间的依赖与制约关系,从经济、信任角度提出自适应的信任-激励相容的资源分配机制.在网格环境中,资源供需的变化会引发价格的浮动,基于经济学的一般均衡理论,给出了资源提供者的动态价格调整策略.提供者可根据当前资源的供需和负载状况,制定自适应的信任-激励相容的分配策略ATIM(adaptive trust-incentive compatible resource allocation),遵循多贡献多分配的原则,激励节点共享出有价值的资源,最大化资源的聚合效用.在CROWN(China research and development environment over wider-area network)平台中评估了ATIM机制的效率和性能. 展开更多
关键词 资源分配 激励 信任 价格策略 CROWN(China research and development ENVIRONMENT over wider-area network)
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军用大功率柴油机电控高压喷油系统的开发方案研究 被引量:3
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作者 张红光 杨青 +2 位作者 李建纯 范伯元 程昌圻 《兵工学报》 EI CAS CSCD 北大核心 2000年第1期64-67,共4页
对目前的电控高压喷油系统进行全面地分析和比较 ,从而确定适合我国国情的军用大功率柴油机电控高压喷油系统开发方案 ,然后对其进行了开发和实验。
关键词 军用大功率柴油机 电控 高压喷油系统 开发方案 A STUDY OF THE DEVELOPMENT MODEL FOR ELECTRONICALLY
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基于Web的水电站大坝巡检系统设计与开发 被引量:6
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作者 郭江 林霖 +2 位作者 曹禹 曾兵 肖志怀 《水电能源科学》 北大核心 2010年第7期54-56,共3页
针对目前水电站大坝巡检系统存在的问题,对巡检对象作了详细剖析后进行了科学、合理的划分,并提出了可扩展的数据库构建模型,开发了基于Web的水电站大坝巡检系统。实践表明,该系统可有效提高工作效率。
关键词 Web Technique 水电站大坝 巡检系统 系统设计 Based INSPECTION DAM Development 构建模型 工作效率 数据库 可扩展 问题 实践 剖析 科学 划分 对象
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基于MDA的TRISO-Model模型管理方法及应用 被引量:6
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作者 袁峰 李明树 《软件学报》 EI CSCD 北大核心 2007年第7期1612-1625,共14页
TRISO-Model(tridimensional integrated software development model)是为处理软件开发的复杂性和动态性而提出的三维集成软件开发方法学,其中,多维模型之间的语义一致性维护以及对模型应用中公共操作部分的重用,提出了基于一致语义进... TRISO-Model(tridimensional integrated software development model)是为处理软件开发的复杂性和动态性而提出的三维集成软件开发方法学,其中,多维模型之间的语义一致性维护以及对模型应用中公共操作部分的重用,提出了基于一致语义进行模型管理的需求.给出了基于MDA(model driven architecture)进行模型管理的方法MDA-MMMethod(MDA based model management method),应用MDA的4层模型管理结构,基于MDA核心标准MOF(meta object facility)所提供的公共语义基础管理模型和元模型,MDA-MMMethod支持各种MDA模型操作标准实现在TRSIO-model应用中的重用.开发了相应的支持系统MDA-MMSystem(MDA based model management system),应用于SoftPM的项目实践中.与传统方法相比,模型应用的开发效率得到了显著提高,同时降低了开发成本.最后,给出了模型融合的应用实例介绍. 展开更多
关键词 TRISO-model(tridimensional integrated software development model) MDA(model driven architecture) MOF(meta object facility)元建模 模型转换
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基于JADE的并行遗传算法的设计与实现 被引量:2
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作者 张秋余 黄鹏 迟宁 《计算机应用》 CSCD 北大核心 2006年第7期1706-1708,1712,共4页
为解决传统遗传算法运行时间过长、寻优率偏低的问题,在研究简单遗传算法的基础上,利用JADE,提出了一种基于多Agent协同工作的并行遗传算法。该算法实现了对客户容器动态加入参与运行的支持。实验结果表明,该算法能较明显地提高传统遗... 为解决传统遗传算法运行时间过长、寻优率偏低的问题,在研究简单遗传算法的基础上,利用JADE,提出了一种基于多Agent协同工作的并行遗传算法。该算法实现了对客户容器动态加入参与运行的支持。实验结果表明,该算法能较明显地提高传统遗传算法的运行效率和寻优的成功率。 展开更多
关键词 并行遗传算法 JAVA AGENT Development Environment(JADE) 多AGENT
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城市森林规划的现状与发展 被引量:8
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作者 刘滨谊 温全平 刘颂 《中国城市林业》 2008年第1期16-21,共6页
分析了城市森林规划在中国发展的背景,通过案例分析,总结比较了英美两国城市森林规划的特点以及中国城市森林规划的特点,从城市森林规划的范围、与城市绿地系统规划的关系、规划对象、内容、方法、城市森林的多功能问题、协调问题、规... 分析了城市森林规划在中国发展的背景,通过案例分析,总结比较了英美两国城市森林规划的特点以及中国城市森林规划的特点,从城市森林规划的范围、与城市绿地系统规划的关系、规划对象、内容、方法、城市森林的多功能问题、协调问题、规划实施和规划立法九个方面探讨了中国城市森林规划的发展。 展开更多
关键词 URBAN FOREST PLANNING CURRENT STATUS Development
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不同灌溉方式对苹果生长发育、产量和品质的影响 被引量:6
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作者 路超 王金政 +1 位作者 薛晓敏 安国宁 《江西农业学报》 CAS 2010年第10期36-39,共4页
研究了起垄覆膜沟灌、树盘埋罐渗灌和树盘漫灌对苹果生长发育、产量和品质的影响。结果表明:与树盘漫灌相比,起垄覆膜沟灌和树盘埋罐渗灌能显著增加新梢和春梢的长度,极显著增加叶面积、比叶重和叶绿素含量,但3个处理的新梢粗度、单株... 研究了起垄覆膜沟灌、树盘埋罐渗灌和树盘漫灌对苹果生长发育、产量和品质的影响。结果表明:与树盘漫灌相比,起垄覆膜沟灌和树盘埋罐渗灌能显著增加新梢和春梢的长度,极显著增加叶面积、比叶重和叶绿素含量,但3个处理的新梢粗度、单株新梢数、秋梢长度、秋梢占新梢数的比例以及产量均无显著差异;树盘埋罐渗灌明显增加了根系的数量,且以直径<2mm根增加最多;起垄覆膜沟灌和树盘埋罐渗灌处理的果实品质总体上优于树盘漫灌。 展开更多
关键词 灌溉方式 苹果 生长发育 产量 果实品质 Growth and Development Different Quality 起垄覆膜 新梢 渗灌 漫灌 沟灌 叶绿素含量 显著差异 处理 长度 叶面积 比叶重 直径
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LEMP模拟装置的研制 被引量:1
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作者 陈亚洲 刘尚合 +1 位作者 魏光辉 魏明 《兵工学报》 EI CAS CSCD 北大核心 2000年第1期83-86,共4页
本文提出了一套雷电电磁脉冲 (LEMP)模拟装置 ,以模拟闪电时的远场电磁环境 ,用于测试电火工品和电子器件对LEMP的感度。它由冲击电压发生器和平行板横电磁室 (PPTC)组成。本文对装置的功能进行了理论分析和实验研究 ,结果表明
关键词 冲击电压发生器 PPTC LEMP 模拟 DEVELOPMENT OF A LIGHTNING ELECTROMAGNETIC PULSE(LEMP)
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