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Practical Magnetotellurics书评
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作者 白登海 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2006年第3期661-661,共1页
关键词 practical 大地电磁测深法 书评 中文译名 剑桥大学 出版社 and
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A Practical and Efficient Procedure for Preparation of Diacetals from 2,2-Bis(hydroxymethyl) propane-1,3-diol with Aldehydes and Ketones Catalysed by Anhydrous Ferrous Sulfate 被引量:6
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期285-285,共1页
关键词 A practical and Efficient Procedure for Preparation of Diacetals from 2 2-Bis HYDROXYMETHYL propane-1 3-diol with Aldehydes and Ketones Catalysed by Anhydrous Ferrous Sulfate
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Analysis of finite-time practical stability for time-varying polytopic systems 被引量:1
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作者 Zhong Zhen Duan Guangren 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第1期112-119,共8页
The problem of finite-time practical stability (FTPS) for time-varying polytopic systems is discussed. Three equivalent conditions for FTPS are first proposed. To facilitate the system analysis, a sufficient linear ... The problem of finite-time practical stability (FTPS) for time-varying polytopic systems is discussed. Three equivalent conditions for FTPS are first proposed. To facilitate the system analysis, a sufficient linear matrix inequality (LMI) criterion on the FTPS is further provided. The definition of finite-time practical boundedness and a sufficient LMI criterion are also provided to overcome the exogenous disturbance. A numerical example is used to illustrate the effect of the proposed approach. 展开更多
关键词 polytopic systems linear matrix inequality finite-time control practical stability.
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Practical synthesis allenyl and homopropargyl alcohol through Cp_2TiCl_2 -Mg with propargyl alcohol derivatives 被引量:1
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期291-291,共1页
Reaction of Cp2TiCl2-Mg synthetic equivalent of practical Ti(II) reagent with propargyl alcohol derivatives affords allenyl titanium compounds in good yields.thus, providing an efficient and practical methods for synt... Reaction of Cp2TiCl2-Mg synthetic equivalent of practical Ti(II) reagent with propargyl alcohol derivatives affords allenyl titanium compounds in good yields.thus, providing an efficient and practical methods for synthesis of both allenyl and homopropargyl alcohols by the successive treatment with aldehydes and ketones. 展开更多
关键词 Mg with propargyl alcohol derivatives practical synthesis allenyl and homopropargyl alcohol through Cp2TiCl2
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Practical φ_0-stability of stochastic differential equations and corresponding stochastic perturbation theory
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作者 赵平 康宇 宗西举 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第S1期235-238,共4页
The notions of practical φ0-stability were introduced for stochastic differential equations. Sufficient conditions on such practical properties were obtained by using the comparison principle and the cone-valued Lyap... The notions of practical φ0-stability were introduced for stochastic differential equations. Sufficient conditions on such practical properties were obtained by using the comparison principle and the cone-valued Lyapunov function methods. Based on an extended comparison theorem, a perturbation theory of stochastic differential systems was given. 展开更多
关键词 practical φ 0-stability STOCHASTIC differential equation comparison principle perturbation theory
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Practical stabilization of receding-horizon control
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作者 LIU Bi yu,GUI Wei hua,MU Min (College of Information Science and Engineering, Central South University, Changsha 410083, China) 《Journal of Central South University of Technology》 2001年第4期268-271,共4页
The purpose of this work is to propose a scheme to stabilize the predictive control systems in the practical stability sense. In the paper, the authors dealt with a general discrete predictive control system x j+1|t =... The purpose of this work is to propose a scheme to stabilize the predictive control systems in the practical stability sense. In the paper, the authors dealt with a general discrete predictive control system x j+1|t =f(x j|t , u j|t ) by using the Lyapunov direct method combining with receding horizon control technique, and presented a new condition to guarantee the practical stabilization of the systems. With the proposed results, one can design the optimal controllers easily to practically stabilize the predictive control systems. 展开更多
关键词 receding-horizon control practical STABILITY LYAPUNOV FUNCTION NONLINEAR system optimization
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PRACTICAL IMPLICATIONS
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《中国运动医学杂志》 CAS CSCD 北大核心 1999年第3期288-,共1页
1.Lifestylefactors,includingchangesindietandphysicalactivitypatterns,areimpoftantincontrollingobesity.2.TheaccumulationofexcessbodyfatappearstobeaProblemresulhngfrominadequatefatoxidationrelativetointake.3.Ifeasyintak... 1.Lifestylefactors,includingchangesindietandphysicalactivitypatterns,areimpoftantincontrollingobesity.2.TheaccumulationofexcessbodyfatappearstobeaProblemresulhngfrominadequatefatoxidationrelativetointake.3.IfeasyintakeexceedsexpenditUre,itispossiblef... 展开更多
关键词 practical IMPLICATIONS
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INSTRUCTIONS FOR AUTHORS
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《Journal of Systems Engineering and Electronics》 2025年第5期F0003-F0003,共1页
Aims and scope Journal of Systems Engineering and Electronics,keeping abreast with the development trend of science and technology worldwide,reports the latest develop-ments and achievements in both theoretical and pr... Aims and scope Journal of Systems Engineering and Electronics,keeping abreast with the development trend of science and technology worldwide,reports the latest develop-ments and achievements in both theoretical and practical aspects of systems engineering,electronicsand related research areas. 展开更多
关键词 practical aspects science technology systems engineeringelectronicsand theoretical aspects systems engineering ELECTRONICS research achievements research areas
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Progress in the Binding of Chloride Ions in Cement-based Materials
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作者 DU Xixian LI Gang +2 位作者 WANG Aiqin CAO Aoli SUN Jianren 《材料导报》 北大核心 2025年第13期100-113,共14页
Chloride ions(Cl^(-))have been shown to impact the long-lasting nature of reinforced concrete.However,Cl^(-)that are already bound inside the concrete will not lead to the deterioration of the concrete’s characterist... Chloride ions(Cl^(-))have been shown to impact the long-lasting nature of reinforced concrete.However,Cl^(-)that are already bound inside the concrete will not lead to the deterioration of the concrete’s characteristics.The composition of the cement-based material,including the type of cement and auxiliary materials,greatly influences the ability of the material to bind Cl^(-),and varied components result in varying binding beha-vior of the Cl^(-).Simultaneously,the Cl^(-)binding process in concrete is influenced by both the internal and exterior surroundings,as well as the curing practices.These factors impact the hydration process of the cement and the internal pore structure of the concrete.Currently,mathematical theories and molecular dynamics simulations have increasingly been employed as the prevalent methods for examining the binding behaviors of Cl^(-)in concrete.These techniques are extensively utilized for predicting the lifespan and conducting microscopic studies of reinforced concrete in Cl^(-)settings.This work proposes recommendations for future research based on a summary of experimental and simulation investigations on Cl^(-)binding.Which will offer theoretical guidance for studying the binding of Cl^(-)in cement-based materials. 展开更多
关键词 cement-based material chloride binding auxiliary material environment curing practice simulation
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美国《保健物理》(Health Physics)杂志英文摘要(2025年128卷第6期)
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《辐射防护》 北大核心 2025年第5期539-544,共6页
Evaluation of Gamma Index Analysis for Detecting Errors in Patient-specific Quality Assurance in Intensity Modulated Radiotherapy Taylan Tugrul1(1.Department of Radiation Oncology,Medicine Faculty of Van Yüzü... Evaluation of Gamma Index Analysis for Detecting Errors in Patient-specific Quality Assurance in Intensity Modulated Radiotherapy Taylan Tugrul1(1.Department of Radiation Oncology,Medicine Faculty of Van YüzüncüYıl University,Van,Turkey)Abstract:Quality assurance practices performed before treatment are believed to identify various potential errors.In this study,2-dimensional(2D)dosimetric results were analyzed by making some intentional mistakes in six different treatment plans.In this way,the detectability of errors was investigated.In all segments of all treatment plans,one of the multileaf collimators was kept fixed at different positions on the central axis.In addition to multileaf collimators error,gantry error was also examined in the study.The dose distribution results obtained by Treatment Planning System(TPS)were compared with those obtained by the 2D array device,both as local calculation and global calculation methods,using the gamma analysis method.When the results are examined in the case where the Multi-leaf collimators(MLC)is fixed at the 1 cm position. 展开更多
关键词 making some intentional mistakes six different treatment plansin multileaf collimators patient specific quality assurance gantry error intensity modulated radiotherapy assurance practices gamma index analysis
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What kind of cotton ideotype is adapted to agroecological cropping systems and climate change in Benin?
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作者 ABOUA Dègbédji Charlemagne GÉRARDEAUX Edward +2 位作者 DEBAEKE Philippe BOULAKIA Stéphane SEKLOKA Emmanuel 《Journal of Cotton Research》 2025年第3期319-332,共14页
Background Agroecological cropping systems are recognised as an alternative way to ensure the sustainability of cotton(Gossypium hirsutum L.) production in the context of climate change and degradation of soil fertili... Background Agroecological cropping systems are recognised as an alternative way to ensure the sustainability of cotton(Gossypium hirsutum L.) production in the context of climate change and degradation of soil fertility. A study was conducted in Benin from 2020 to 2023 to compare six different cotton cultivars in three agroecological cropping systems in two cotton-growing zones. Plough-based tillage plus incorporation of cover crop biomass(PTI), conservation agriculture with strip tillage(CA_ST), and conservation agriculture with no tillage(CA_NT) were compared with the reference plough-based tillage(PT). The objective was to identify morpho-physiological traits of cotton that increase yield in agroecological cropping systems. Our approach combined a field experiment and crop simulation model(CSM) of CROPGRO-Cotton to evaluate the effects of genotype(G) × environment(E) × management(M) interactions on seed cotton yield(SCY).Results Cultivars Tamcot_camde and Okp768 and simulated ideotypes performed best in CA systems. Increased seed mass, large and thick leaves, and later maturity were identified as beneficial for yield enhancement in CA systems. Cultivars and ideotypes that combine these traits also resulted in better nitrogen and water use efficiencies in CA systems. Under different climate scenarios up to 2050, ideotypes designed could increase SCY in Benin.Conclusion A set of morpho-physiological traits associated with vegetative vigour is required to ensure a good SCY in agroecological cropping systems. These results provide scientific evidence and useful knowledge for breeders and research programmes on cropping systems focused on the adaptation of cotton to climate change. 展开更多
关键词 TILLAGE Agroecological practices Water status Gossypium hirsutum IDEOTYPE Seed cotton yield Cover crop CSM-CROPGRO-Cotton
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基于PCCS色彩体系的装饰设计色彩规律再认识 被引量:5
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作者 廖风华 《室内设计》 2009年第4期61-64,共4页
对装饰设计中的色彩规律进行系统认识十分必要。在分析PCCS色彩体系的基础上,本文将色彩间的基本相互作用归纳为PCCS中的空间矢量及其分矢量,并以辩证统一的方法对常见色彩规律(对比、同化及调和等)进行了系统和直观的阐释。
关键词 空间维度 色彩规律 空间矢量 practical COLOR COORDINATE System
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两个务实的人中间的务实婚姻 --析《傲慢与偏见》(英文)
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作者 陈谦红 陈炳丽 《思想战线》 CSSCI 北大核心 2010年第S1期331-333,共3页
Jane Austen begins Pride and Prejudice with "It is a truth universally acknowledged that, a single man in possession of a good fortune, must be in want of a wife."Hence, there is no doubt that marriage will ... Jane Austen begins Pride and Prejudice with "It is a truth universally acknowledged that, a single man in possession of a good fortune, must be in want of a wife."Hence, there is no doubt that marriage will be a central concern of Pride and Prejudice. In this novel, Austen depicted several types of marriage: Elizabeth and Darcy’s marriage which emphasized equality and independence, Jane and Bingley’s marriage for love’s sake, Charlotte Lucas and Mr. Collins’ practical marriage and the rash marriage between Lydia and Wickham. This thesis is focused on the practical marriage between Charlotte Lucas and Mr. Collins while further explores the reasons behind their pragmatism. 展开更多
关键词 practical MARRIAGE OLD maid AUSTEN
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近期热点文章
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作者 庄林 《电化学》 CAS CSCD 北大核心 2014年第3期293-294,共2页
Suppression of Lithium Dendrite Growth Using Cross-Linked Polyethylene/Poly(ethylene oxide)Electrolytes:A New Approach for Practical Lithium-Metal Polymer Batteries R.Khurana,J.L.Schaefer,L.A.Archer,G.W.Coates J.Am... Suppression of Lithium Dendrite Growth Using Cross-Linked Polyethylene/Poly(ethylene oxide)Electrolytes:A New Approach for Practical Lithium-Metal Polymer Batteries R.Khurana,J.L.Schaefer,L.A.Archer,G.W.Coates J.Am.Chem.Soc.DOI:10.1021/ja502133j将聚乙烯和聚氧乙烯的交联共聚物用作金属锂电池隔膜,不仅获得较高的离子电导率,还可抑制锂枝晶的生长. 展开更多
关键词 practical 交联共聚物 离子电导率 电池隔膜 聚氧乙烯 金属锂 聚乙烯
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雅思口语测试的效度、信度和实用性探析(英文) 被引量:2
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作者 任勤 《思想战线》 CSSCI 北大核心 2010年第S1期281-283,共3页
IELTS conforms to the highest international standards of language assessment, testing four language skills-listening, reading, writing and speaking, which are equally weighted with scores reported on a 9-band scale of... IELTS conforms to the highest international standards of language assessment, testing four language skills-listening, reading, writing and speaking, which are equally weighted with scores reported on a 9-band scale of ability. Every candidate needs to take the same Listening and Speaking modules. The Speaking test of IELTS measures a candidate’s general proficiency in speaking in everyday situations via a structured, five-phase oral interview. As a performance test, the IELTS Speaking test has been one of the most important issues in the assessment of English proficiency. Assessment needs to be theory driven. For this reason, this paper will focus on validity, reliability and practicality of the IELTS Speaking test, qualities that affect assessment design. 展开更多
关键词 IELTS SPEAKING TEST validity RELIABILITY practicalITY
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我国草莓新品种选育进展及育种实践 被引量:33
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作者 万春雁 糜林 +2 位作者 李金凤 霍恒志 陈雪平 《江西农业学报》 CAS 2010年第11期37-39,44,共4页
综述了我国草莓生产中的品种变迁、新品种的选育,介绍了江苏丘陵地区镇江农业科学研究所的草莓育种实践,提出了当前草莓育种工作中存在的不足及应对措施。
关键词 草莓新品种 选育进展 育种实践 Practice China New 科学研究所 育种工作 应对措施 丘陵地区 草莓生产 镇江 农业 江苏
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仿双面绣提花工艺织品开发实践 被引量:5
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作者 胡丽华 陈倩 +1 位作者 刘娜 眭建华 《丝绸》 CAS 北大核心 2010年第10期39-41,共3页
采用提花织造技术开发仿双面绣工艺织品,探讨设计工艺要点与产品效果。从纹样叠合、组织结构配置、接结要求入手,分析了形成双面异纹提花的原理,结合实例阐述了设计仿双面绣织物在纹样设计、叠合组织配置等的基本要点,提出了提花织造工... 采用提花织造技术开发仿双面绣工艺织品,探讨设计工艺要点与产品效果。从纹样叠合、组织结构配置、接结要求入手,分析了形成双面异纹提花的原理,结合实例阐述了设计仿双面绣织物在纹样设计、叠合组织配置等的基本要点,提出了提花织造工艺实现仿双面绣工艺织品的路径与存在问题。结果表明,双面异纹提花技术开发的产品有较好的仿双面绣效果。 展开更多
关键词 双面 提花织造 织造工艺 开发实践 JACQUARD Fabric Practice 技术开发 纹样设计 组织配置 结构配置 工艺要点 叠合 存在问题 产品 织物 路径 结果 分析
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变速直驱开关磁阻风力发电系统的控制与实现 被引量:7
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作者 熊立新 高厚磊 +1 位作者 徐丙垠 贺益康 《太阳能学报》 EI CAS CSCD 北大核心 2010年第6期782-788,共7页
对开关磁阻发电机的运行原理和风轮机的功率输出特性进行了分析,提出了一种不依赖风轮机运行参数即可实现最大风能跟踪的控制方法。使用MATLAB/SIMULINK构建了系统模型,进行了仿真,并在试验室中进行了验证。设计了一套10kW开关磁阻风力... 对开关磁阻发电机的运行原理和风轮机的功率输出特性进行了分析,提出了一种不依赖风轮机运行参数即可实现最大风能跟踪的控制方法。使用MATLAB/SIMULINK构建了系统模型,进行了仿真,并在试验室中进行了验证。设计了一套10kW开关磁阻风力发电系统并应用到现场,实现了变速直驱发电,给出了部分现场数据,证明直驱式开关磁阻风力发电是可行的。 展开更多
关键词 变速 开关磁阻发电机 风力发电系统 控制方法 PRACTICE MATLAB/SIMULINK 最大风能跟踪 功率输出特性 风轮机 运行原理 运行参数 现场数据 系统模型 直驱式 试验室 证明 验证 设计 构建 分析
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南方复杂山地三维地震勘探实践与效果分析 被引量:12
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作者 敬朋贵 殷厚成 陈祖庆 《石油物探》 EI CSCD 北大核心 2010年第5期495-499,19,共5页
南方海相碳酸盐岩油气勘探历史较长,以前虽有所发现,但规模有限。近几年来,随着三维地震勘探技术的发展及其在南方复杂山地的大规模实施,中国石油化工股份有限公司相继在川东北地区海相油气勘探领域取得了巨大发现。勘探实践表明,三维... 南方海相碳酸盐岩油气勘探历史较长,以前虽有所发现,但规模有限。近几年来,随着三维地震勘探技术的发展及其在南方复杂山地的大规模实施,中国石油化工股份有限公司相继在川东北地区海相油气勘探领域取得了巨大发现。勘探实践表明,三维地震勘探技术大幅度改善了该地区的地震资料品质,为解决复杂地质问题奠定了良好的资料基础,从而提高了碳酸盐岩储层预测和描述的精度,大大加快了油气勘探节奏。从普光大型气田的探明到元坝大型礁滩体的发现,充分表明三维地震勘探技术在南方复杂海相油气勘探中发挥了不可替代的作用。 展开更多
关键词 南方 山地三维地震 勘探实践 效果分析 Southern China mountainous area effect analysis practice seismic exploration 三维地震勘探技术 油气勘探领域 海相碳酸盐岩 股份有限公司 地震资料品质 油气勘探中 川东北地区 石油化工 勘探历史 复杂山地 地质问题
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卡马水库应急除险工作的启示 被引量:2
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作者 刘宁 黄金池 张启义 《水科学进展》 EI CAS CSCD 北大核心 2010年第6期742-747,共6页
2009年汛期,广西河池卡马水库右岸溢洪道附近发生垮塌,大坝安全风险骤然增加。在应急除险实践中,同时对大坝不同状态进行了有限元渗流分析及采用非线性指标进行边坡稳定分析,初步确定出险位置可能处于放空洞中段,在此基础上,对水库溃决... 2009年汛期,广西河池卡马水库右岸溢洪道附近发生垮塌,大坝安全风险骤然增加。在应急除险实践中,同时对大坝不同状态进行了有限元渗流分析及采用非线性指标进行边坡稳定分析,初步确定出险位置可能处于放空洞中段,在此基础上,对水库溃决风险进行了分析,得出了风险决策依据,从而提出减灾措施,有效降低了水库溃决的风险。从卡马水库的应急处置出发,探讨了中国水库应急除险的关键技术,并提出了中国水库安全管理相关的一些重要问题。 展开更多
关键词 水库 除险 启示 practice 安全风险 边坡稳定分析 非线性指标 中国 应急处置 渗流分析 溃决 决策依据 减灾措施 广西河池 关键技术 大坝 不同状态 安全管理 有限元 溢洪道
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