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On the Optimal Initial Inner-Core Size for Tropical Cyclone Intensification: An Idealized Numerical Study
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作者 Rong FEI Yuqing WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第11期2141-2155,共15页
Recent observational and numerical studies have revealed the dependence of the intensification rate on the inner-core size of tropical cyclones(TCs). In this study, with the initial inner-core size(i.e., the radius of... Recent observational and numerical studies have revealed the dependence of the intensification rate on the inner-core size of tropical cyclones(TCs). In this study, with the initial inner-core size(i.e., the radius of maximum wind—RMW)varied from 20–180 km in idealized simulations using two different numerical models, we found a nonmonotonic dependence of the lifetime maximum intensification rate(LMIR) on the inner-core size. Namely, there is an optimal innercore size for the LMIR of a TC. Tangential wind budget analysis shows that, compared to large TCs, small TCs have large inward flux of absolute vorticity due to large absolute vorticity inside the RMW. However, small TCs also suffer from strong lateral diffusion across the eyewall, which partly offsets the positive contribution from large inward flux of absolute vorticity. These two competing processes ultimately lead to the TC with an intermediate initial inner-core size having the largest LMIR. Results from sensitivity experiments show that the optimal size varies in the range of 40–120 km and increases with higher sea surface temperature, lower latitude, larger horizontal mixing length, and weaker initial TC intensity. The 40–120 km RMW corresponds to the inner-core size most commonly found for intensifying TCs in observations, suggesting the natural selection of initial TC size for intensification. This study highlights the importance of accurate representation of TC inner-core size to TC intensity forecasts by numerical weather prediction models. 展开更多
关键词 tropical cyclones INTENSIFICATION inner-core size idealized simulations
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INCOMPRESSIBLE LIMIT OF IDEAL MAGNETOHYDRODYNAMICS IN A DOMAIN WITH BOUNDARIES
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作者 Qiangchang JU Jiawei WANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1441-1465,共25页
We study the incompressible limit of classical solutions to compressible ideal magneto-hydrodynamics in a domain with a flat boundary.The boundary condition is characteristic and the initial data is general.We first e... We study the incompressible limit of classical solutions to compressible ideal magneto-hydrodynamics in a domain with a flat boundary.The boundary condition is characteristic and the initial data is general.We first establish the uniform existence of classical solutions with respect to the Mach number.Then,we prove that the solutions converge to the solution of the incompressible MHD system.In particular,we obtain a stronger convergence result by using the dispersion of acoustic waves in the half space. 展开更多
关键词 incompressible limit ideal MHD equations boundary condition general initial data
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基于“IDEAL”模式的物理问题解决能力培养研究
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作者 杨卓璇 林钦 《中学理科园地》 2024年第3期46-48,51,共4页
学生“物理问题解决能力弱”是长期困扰物理教学的问题,认知心理学关于问题解决的“IDEAL”模式为该问题的研究提供了新的视角。以2022年全国乙卷理综第25题为例,借助“IDEAL”模式可以清晰地梳理问题解决的过程,明确各阶段学生遇到的... 学生“物理问题解决能力弱”是长期困扰物理教学的问题,认知心理学关于问题解决的“IDEAL”模式为该问题的研究提供了新的视角。以2022年全国乙卷理综第25题为例,借助“IDEAL”模式可以清晰地梳理问题解决的过程,明确各阶段学生遇到的困难及成因。研究发现,借助“读思达”教学法,通过粗读、精读等过程,可以有效帮助学生建构物理模型、理清物理过程,从而提高物理问题解决能力。 展开更多
关键词 问题解决 “IDEAL”模式 “读思达”教学法
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Yeats’s Ideals:Women Old and Young
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作者 DONG Qian 《Journal of Literature and Art Studies》 2024年第5期330-334,共5页
William Butler Yeats ranks among the most widely admired and intensively studied poets of the 20th century.This paper intends to explore the women who have exerted the most critical influences upon Yeats,namely Gonne,... William Butler Yeats ranks among the most widely admired and intensively studied poets of the 20th century.This paper intends to explore the women who have exerted the most critical influences upon Yeats,namely Gonne,Lady Gregory,and Georgie Hyde-Lees.Even in Yeats’s poetry involved with symbolism,it is worth noting that his employment of symbols has used these women as the archetypes,and that the historical context rendered Yeats’s representations of them in his poetry all the more interesting. 展开更多
关键词 IDEALS WOMEN representation SYMBOLISM OCCULT
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For the Ideal Homeland
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作者 ZHOU LIN 《China Today》 2024年第7期62-64,共3页
A town planner combines British experience with Chinese concept of harmony to build green,low-carbon,and sustainable cities.YANG Wei is a woman who wears many hats.An internationally renowned town planner and urban de... A town planner combines British experience with Chinese concept of harmony to build green,low-carbon,and sustainable cities.YANG Wei is a woman who wears many hats.An internationally renowned town planner and urban designer,she is held in high esteem in the academic and planning communities in the U.K.and is a fellow of the U.K.Academy of Social Sciences and former president of the Royal Town Planning Institute(RTPI)based in London.She is also chief executive and co-founder of the Digital Task Force for Planning(DTFP),a non-profit social enterprise,and founding director of London-based planning and urban design firm Wei Yang&Partners. 展开更多
关键词 FOUNDING HARMONY IDEAL
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Hypothetical Dark Matter Explains the Origin of Subatomic Universe: FEP-Theory
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作者 Ali Moghaddasi Hassan Yousefnia 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1643-1654,共12页
Although the standard model provides a suitable pattern based on observable experimental data, it cannot explain dark matter, gravitation, the structural nature of the fundamental particles, and charges. In this paper... Although the standard model provides a suitable pattern based on observable experimental data, it cannot explain dark matter, gravitation, the structural nature of the fundamental particles, and charges. In this paper, a new theory about the nature of charges, particles and proposed structures for atoms were presented. This theory explains how an ideal quantum fluid (IQF) including hypothetical dark matter or fundamental elementary particles (FEPs) can produce the building blocks of matter. This theory describes quadruple blocks with two types of independent charges that can create different characteristics for these building blocks. Quadruple blocks have similarities and differences with the fundamental particles in standard model. This theory also explains the possible mechanism of creation the next generation of particles such as protons and neutrons. 展开更多
关键词 THEORY Statistical Thermodynamics Ideal Quantum Fluid Fundamental Elementary Particles
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Solving Some Problems and Elimination in Systems of Polynomial Equations
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作者 Moumouni Djassibo Woba 《American Journal of Computational Mathematics》 2024年第3期333-345,共13页
In a factorial ring, we can define the p.g.c.d. of two elements (defined to the nearest unit) and the notion of prime elements between them. More generally, Bezout’s identity characterizes two prime elements in a mai... In a factorial ring, we can define the p.g.c.d. of two elements (defined to the nearest unit) and the notion of prime elements between them. More generally, Bezout’s identity characterizes two prime elements in a main ring. A ring that satisfies the property of the theorem is called a Bezout ring. We have given some geometry theorems that can be proved algebraically, although the methods of geometry and, in particular, of projective geometry are by far the most beautiful. Most geometric problems actually involve polynomial equations and can be translated into the language of polynomial ideals. We have given a few examples of a different nature without pretending to make a general theory. 展开更多
关键词 Identity of Bezout Ring of Bezout IDEALS POLYNOMIALS COMMON
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Derivation of a Revised Tsiolkovsky Rocket Equation That Predicts Combustion Oscillations
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作者 Zaki Harari 《Advances in Aerospace Science and Technology》 2024年第1期10-27,共18页
Our study identifies a subtle deviation from Newton’s third law in the derivation of the ideal rocket equation, also known as the Tsiolkovsky Rocket Equation (TRE). TRE can be derived using a 1D elastic collision mod... Our study identifies a subtle deviation from Newton’s third law in the derivation of the ideal rocket equation, also known as the Tsiolkovsky Rocket Equation (TRE). TRE can be derived using a 1D elastic collision model of the momentum exchange between the differential propellant mass element (dm) and the rocket final mass (m1), in which dm initially travels forward to collide with m1 and rebounds to exit through the exhaust nozzle with a velocity that is known as the effective exhaust velocity ve. We observe that such a model does not explain how dm was able to acquire its initial forward velocity without the support of a reactive mass traveling in the opposite direction. We show instead that the initial kinetic energy of dm is generated from dm itself by a process of self-combustion and expansion. In our ideal rocket with a single particle dm confined inside a hollow tube with one closed end, we show that the process of self-combustion and expansion of dm will result in a pair of differential particles each with a mass dm/2, and each traveling away from one another along the tube axis, from the center of combustion. These two identical particles represent the active and reactive sub-components of dm, co-generated in compliance with Newton’s third law of equal action and reaction. Building on this model, we derive a linear momentum ODE of the system, the solution of which yields what we call the Revised Tsiolkovsky Rocket Equation (RTRE). We show that RTRE has a mathematical form that is similar to TRE, with the exception of the effective exhaust velocity (ve) term. The ve term in TRE is replaced in RTRE by the average of two distinct exhaust velocities that we refer to as fast-jet, vx<sub>1</sub>, and slow-jet, vx<sub>2</sub>. These two velocities correspond, respectively, to the velocities of the detonation pressure wave that is vectored directly towards the exhaust nozzle, and the retonation wave that is initially vectored in the direction of rocket propagation, but subsequently becomes reflected from the thrust surface of the combustion chamber to exit through the exhaust nozzle with a time lag behind the detonation wave. The detonation-retonation phenomenon is supported by experimental evidence in the published literature. Finally, we use a convolution model to simulate the composite exhaust pressure wave, highlighting the frequency spectrum of the pressure perturbations that are generated by the mutual interference between the fast-jet and slow-jet components. Our analysis offers insights into the origin of combustion oscillations in rocket engines, with possible extensions beyond rocket engineering into other fields of combustion engineering. 展开更多
关键词 Tsiolkovsky Rocket Equation Ideal Rocket Equation Rocket Propulsion Newton’s Third Law Combustion Oscillations Combustion Instability
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The Axiology of Consciousness in Mocombeian Consciousness Field Theory
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作者 Paul C.Mocombe 《Philosophy Study》 2024年第4期168-185,共18页
This work explores the axiology of consciousness in Mocombe’s consciousness field in the material world.The paper critically assesses Mocombe’s consciousness field theory(CFT)within the larger body of contemporary o... This work explores the axiology of consciousness in Mocombe’s consciousness field in the material world.The paper critically assesses Mocombe’s consciousness field theory(CFT)within the larger body of contemporary ontological debates regarding the nature,origin,and constitution of consciousness in the universe.The work goes on to highlight the manifestation of Mocombe’s consciousness field in the material resource framework that is the earth,and the nature and origins of ethics and values. 展开更多
关键词 structuration theory phenomenological structuralism structure/agency mythopraxis quantum mechanics social class language game Haitian epistemology Haitian/Vilokan idealism consciousness field theory
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An Empirical Evaluation of the Impact of Moral and Law Course Teaching on the Effectiveness of University Students’Ideals and Beliefs Education
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作者 Aiai Yang 《Journal of Contemporary Educational Research》 2024年第10期148-152,共5页
The Moral and Law course serves as a critical platform for educating university students about ideals and beliefs,and it has a significant impact on the effectiveness of ideals and beliefs education.This paper establi... The Moral and Law course serves as a critical platform for educating university students about ideals and beliefs,and it has a significant impact on the effectiveness of ideals and beliefs education.This paper establishes a mechanism through which Moral and Law course teaching influences the effectiveness of ideals and beliefs education and conducts an empirical evaluation.The results reveal that factors such as the relevance and applicability of the teaching content,the integration of theory and practice,the innovation,interactivity,and participation of teaching methods,as well as classroom atmosphere,teaching facilities,and campus culture,all have a significant positive impact on the effectiveness of ideals and beliefs education for university students. 展开更多
关键词 Ideals and beliefs education Moral and Law course Empirical evaluation
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IDEAL序列在脊柱脂肪抑制中的应用 被引量:9
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作者 黄敏华 郭勇 +2 位作者 郑奎宏 林伟 张静 《中国医学影像学杂志》 CSCD 北大核心 2012年第1期2-4,共3页
目的比较IDEALT2WI、FSET2WI序列在脊柱脂肪抑制扫描中的应用价值。资料与方法 35例脊柱MRI检查患者(颈椎10例、胸椎8例、腰椎17例)同时采用IDEALT2WI、FSET2WI两种脂肪抑制序列扫描,对图像脂肪抑制质量进行主观评价分级评估并测量信噪... 目的比较IDEALT2WI、FSET2WI序列在脊柱脂肪抑制扫描中的应用价值。资料与方法 35例脊柱MRI检查患者(颈椎10例、胸椎8例、腰椎17例)同时采用IDEALT2WI、FSET2WI两种脂肪抑制序列扫描,对图像脂肪抑制质量进行主观评价分级评估并测量信噪比。结果 FSET2WI脂肪抑制质量主观评价分级为颈椎(1.30±0.48)级、胸椎(1.80±0.71)级、腰椎(2.30±0.69)级,而IDEALT2WI序列颈、胸椎均为(3.00±0.00)级、腰椎为(2.80±0.56)级;FSET2WI脂肪抑制序列信噪比平均值分别为颈(8.73±4.66)、胸(11.33±9.27)、腰(6.81±10.15),IDEALT2WI序列信噪比平均值分别为颈(18.90±7.71)、胸(26.02±11.61)、腰(19.57±9.12),两序列信噪比差异有统计学意义(t=3.73、5.72、11.23,P<0.05)。结论脊柱MRI脂肪抑制扫描IDEALT2WI序列优于FSET2WI序列,IDEALT2WI序列能提供更均匀稳定的脂肪抑制效果,脊柱图像信噪比高,可清晰显示脊柱病变。 展开更多
关键词 IDEAL序列 脊柱 脂肪抑制 磁共振成像
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求解流动与传热问题的一种高效稳定的分离式算法—IDEAL 被引量:7
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作者 孙东亮 屈治国 +1 位作者 何雅玲 陶文铨 《工程热物理学报》 EI CAS CSCD 北大核心 2009年第8期1369-1372,共4页
本文提出了一种求解流动与传热问题的高效稳定的分离式算法—IDEAL(Inner Doubly-iterative Efficient Algorithm for Linked-equations)。在IDEAL算法中每个迭代层次上对压力方程进行两次内迭代计算,第一次内迭代过程用于克服SIMPLE算... 本文提出了一种求解流动与传热问题的高效稳定的分离式算法—IDEAL(Inner Doubly-iterative Efficient Algorithm for Linked-equations)。在IDEAL算法中每个迭代层次上对压力方程进行两次内迭代计算,第一次内迭代过程用于克服SIMPLE算法的第一个假设,第二次内迭代过程用于克服SIMPLE算法的第二个假设。这样在每个迭代层次上充分满足了速度和压力之间的耦合,从而大大提高了计算的收敛速度和计算过程的稳定性。本文通过2个三维不可压缩流动和传热的算例对IDEAL算法与其它三个被广泛使用的算法(SIMPLER、SIMPLEC和PISO)进行了比较。通过分析比较得出IDEAL算法在收敛性和健壮性上均优于SIMPLER、SIMPLEC和PISO算法。在这2个算例中IDEAL算法几乎可以在任意的松弛因子下获得收敛的解,并且IDEAL算法所需最短计算时间较SIMPLER算法减少12.9%~52.6%;较SIMPLEC算法减少48.3%~79.1%;较PISO算法减少10.7%~46.5%。 展开更多
关键词 分离式算法 IDEAL 收敛速度 健壮性
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Implicative and Fuzzy Implicative Ideals of Lattice Implication Algebras 被引量:11
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作者 赵光峰 徐扬 宋振明 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第4期104-110,共7页
In this paper, we defined the concept of implicative and fuzzy implicative ideals of lattice implication algebras, and discussed the properties of them. And then, we pointed out the relations between implicative ideal... In this paper, we defined the concept of implicative and fuzzy implicative ideals of lattice implication algebras, and discussed the properties of them. And then, we pointed out the relations between implicative ideal and LI _ideal, implicative iedal and implicative filter, implicative ideal and fuzzy implicative ideal, fuzzy implicative ideal and fuzzy implicative filter, and fuzzy implicative ideal and fuzzy LI _ideal. 展开更多
关键词 lattice implication algebra fuzzy LI _ideal fuzzy filter implicative ideal fuzzy implicative ideal
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3.0T MR IDEAL和T2 mapping成像在腰椎间盘退变中的应用 被引量:19
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作者 葛涌钱 周学军 +2 位作者 包雪平 曹亮 吴献华 《中国CT和MRI杂志》 2015年第2期81-83,87,共4页
目的探讨磁共振IDEAL和T2mapping成像技术在腰椎间盘退变中的应用价值。方法前瞻性选择有腰椎间盘退变症状的患者30例,分别进行腰椎矢状位T2 IDEAL成像、矢状位T1Flair加权成像、横轴位椎间盘T2FSE成像及矢状位T2mapping成像。在矢状位I... 目的探讨磁共振IDEAL和T2mapping成像技术在腰椎间盘退变中的应用价值。方法前瞻性选择有腰椎间盘退变症状的患者30例,分别进行腰椎矢状位T2 IDEAL成像、矢状位T1Flair加权成像、横轴位椎间盘T2FSE成像及矢状位T2mapping成像。在矢状位IDEAL水相位图像上,参考Pfirrmann分级方法,把L2-L3、L3-L4、L4-L5、L5-S1椎间盘进行分级,然后在正中矢状位T2 mapping图像上选择感兴趣区(ROI),测量椎间盘中髓核(NP)的T2值,进行统计学分析,比较分析椎间盘退变分级与T2值之间的相关性。结果一共测量120个椎间盘T2值,随着分级的增加,L2-S1椎间盘NP的T2值减小,Ⅳ级与Ⅴ级间差异无统计学意义(p>0.05),其余各级间差异具有统计学意义(p<0.05)。结论 IDEAL和T2 mapping成像结合起来分析,定性定量的观察椎间盘退变情况,在椎间盘退变中具有较高的应用价值。 展开更多
关键词 磁共振成像 椎间盘退变 IDEAL序列 横向弛豫时间
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3.0T MRI IDEAL序列对腰骶神经成像的可行性研究 被引量:8
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作者 孙莉华 宋云龙 +3 位作者 王东 李相生 李海宁 王冬梅 《中国医学影像学杂志》 CSCD 北大核心 2015年第2期135-139,共5页
目的初步探讨3.0T MRI IDEAL序列显示正常人腰骶神经结构形态及神经根受压后形态结构变化的可行性,评估其同时显示腰骶神经根细微结构及全程形态特点的价值。资料与方法 25例健康志愿者和15例腰腿痛患者行IDEAL序列腰骶神经冠状位成像... 目的初步探讨3.0T MRI IDEAL序列显示正常人腰骶神经结构形态及神经根受压后形态结构变化的可行性,评估其同时显示腰骶神经根细微结构及全程形态特点的价值。资料与方法 25例健康志愿者和15例腰腿痛患者行IDEAL序列腰骶神经冠状位成像及后处理重建,观察图像中L1~S1各水平腰骶神经显示情况,包括腰骶神经走形、节前神经长度、神经根鞘长度及神经节大小。结果 1 L1~S1各水平节前神经、脊神经节以及L3~S1各水平节后神经显示率达100%,并且形态结构清晰;L1及L2水平节后神经形态结构能够清晰显示达Ⅰ级的显示率分别为12%和42%,达Ⅱ级显示欠清晰者分别为16%和32%,达Ⅲ级结构辨认不清者分别为72%和26%。各水平节前神经、神经节长径、神经节橫径及神经根鞘长度从L1~S1逐渐增大(P〈0.05、P〈0.001)。正常腰骶神经根走形于腰神经通道内,表现为边缘光滑,高信号脑脊液衬托下的条形等信号。结论 IDEAL序列腰骶神经成像可以清晰直观地显示正常腰骶神经根的形态走形和细微结构特点,以及腰骶神经根受压后的变化,能够为临床准确评估腰腿痛患者神经根受压的变化与手术治疗提供参考标准和影像资料。 展开更多
关键词 腰骶丛 脊神经根 磁共振成像 IDEAL序列
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表皮生长因子受体酪氨酸激酶抑制剂吉非替尼 被引量:13
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作者 张艳华 宁华 姜洋 《中国新药杂志》 CAS CSCD 北大核心 2004年第10期947-950,共4页
吉非替尼(ZD1839,Iressa)是一种表皮生长因子受体酪氨酸激酶抑制剂,通过阻断酪氨酸激酶信号传导通路抑制肿瘤生长。2个大型的Ⅱ期临床试验(IDEAL)证实了其对于晚期非小细胞肺癌具有应用前景,可以改善症状,延长患者的生存期。此外,在对... 吉非替尼(ZD1839,Iressa)是一种表皮生长因子受体酪氨酸激酶抑制剂,通过阻断酪氨酸激酶信号传导通路抑制肿瘤生长。2个大型的Ⅱ期临床试验(IDEAL)证实了其对于晚期非小细胞肺癌具有应用前景,可以改善症状,延长患者的生存期。此外,在对多种恶性实体瘤的Ⅰ期和Ⅱ期临床研究中也初步证实了该药具有抗肿瘤活性。 展开更多
关键词 吉非替尼 酪氨酸激酶抑制剂 表皮生长因子受体 Ⅱ期临床试验 ZD1839 晚期非小细胞肺癌 Ⅱ期临床研究 IDEAL 改善 延长
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3.0T磁共振IDEAL序列在臂丛神经病变诊断中的应用价值 被引量:4
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作者 刘新疆 夏吉凯 +3 位作者 房清敏 张迪 范万峰 王滨 《医学影像学杂志》 2013年第12期2004-2007,共4页
目的探讨臂丛神经病变在3.0T MRI IDEAL序列中的表现,确定其临床应用价值。方法手术确诊3例神经纤维瘤病,临床诊断14例臂丛损伤患者采用IDEAL技术扫描,观察其影像表现。结果 3例神经源性肿瘤清晰显示了肿块部位及其与神经关系。14例臂... 目的探讨臂丛神经病变在3.0T MRI IDEAL序列中的表现,确定其临床应用价值。方法手术确诊3例神经纤维瘤病,临床诊断14例臂丛损伤患者采用IDEAL技术扫描,观察其影像表现。结果 3例神经源性肿瘤清晰显示了肿块部位及其与神经关系。14例臂丛神经损伤患者:节前损伤6例,节后损伤5例,节前并节后损伤3例。结论 IDEAL序列对臂丛损伤及病变的显示清晰、准确,可以在臂丛神经病变MRI检查中常规应用。 展开更多
关键词 IDEAL序列 水脂分离技术 臂丛神经损伤 磁共振成像
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软件过程改进中的知识管理初探 被引量:11
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作者 万江平 杨建梅 《计算机应用研究》 CSCD 北大核心 2002年第5期1-3,共3页
首先介绍了软件过程改进和管理复杂性理论的概念;接着从能力成熟度模型及其 实施系统方法论IDEAL模型分别分析了软件过程改进中的知识管理和组织学习;最后对软件 组织的知识管理进行了探讨,指出软件过程改进是通过有效地组织学习进行... 首先介绍了软件过程改进和管理复杂性理论的概念;接着从能力成熟度模型及其 实施系统方法论IDEAL模型分别分析了软件过程改进中的知识管理和组织学习;最后对软件 组织的知识管理进行了探讨,指出软件过程改进是通过有效地组织学习进行知识管理的有效 途径。 展开更多
关键词 软件过程改进 能力成熟度模型 IDEAL模型 知识管理 组织学习 软件工程
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外科学创新技术评估方法:IDEAL框架 被引量:4
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作者 锁涛 黄丽红 +4 位作者 纪颖 王波 丁昉 陈英耀 孙湛 《中国医院管理》 北大核心 2019年第11期32-35,共4页
新型外科手术技术的评估流程十分复杂,对外科手术创新中进行高质量的客观评估存在着种种困难,IDEAL(Idea,Development,Exploration,Assessment,and Long-term follow up)是目前被广泛认可的外科领域临床研究方法学框架,包括(1)思路创新... 新型外科手术技术的评估流程十分复杂,对外科手术创新中进行高质量的客观评估存在着种种困难,IDEAL(Idea,Development,Exploration,Assessment,and Long-term follow up)是目前被广泛认可的外科领域临床研究方法学框架,包括(1)思路创新阶段,(2a)发展阶段,(2b)探索阶段,(3)评估阶段,(4)长期随访阶段。详细介绍IDEAL框架的5阶段研究思路,并结合案例分析,旨在推荐国内外科临床研究者使用IDEAL方法遴选外科新技术问题、开展外科临床研究,最终改善外科研究的大环境,提高外科手术或其他复杂干预临床研究的质量。 展开更多
关键词 外科学 新技术 IDEAL
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不同网格扭曲率下压力修正全隐算法——IDEAL求解性能研究 被引量:2
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作者 孙东亮 王艳宁 +2 位作者 张奥林 宇波 李汉勇 《计算力学学报》 CAS CSCD 北大核心 2017年第2期183-190,共8页
2008年,本文作者和陶文铨等提出了一种用于速度和压力耦合求解的高效稳定压力修正全隐算法IDEAL,该算法通过在每个迭代层次上对压力方程进行两次内迭代计算,完全克服了SIMPLE算法的两个假设,充分满足了速度和压力之间的耦合,从而大大提... 2008年,本文作者和陶文铨等提出了一种用于速度和压力耦合求解的高效稳定压力修正全隐算法IDEAL,该算法通过在每个迭代层次上对压力方程进行两次内迭代计算,完全克服了SIMPLE算法的两个假设,充分满足了速度和压力之间的耦合,从而大大提高了计算的收敛性和健壮性。为了进一步实现IDEAL算法的推广应用,本文基于三维倾斜方腔顶盖驱动流动,研究了IDEAL算法在不同网格扭曲率下的求解特性。研究发现,在不同网格扭曲率下,IDEAL算法的健壮性和收敛性均优于SIMPLE算法,特别在高网格扭曲率情况下,IDEAL算法求解性能更加优于SIMPLE算法。在不同网格扭曲率下,IDEAL算法健壮性保持不变,几乎可以在任意速度亚松弛因子下获得收敛的解,同时IDEAL算法最短计算耗时较SIMPLE算法减少了56%~89%,验证了IDEAL算法的优越性。 展开更多
关键词 压力修正算法 IDEAL 网格扭曲率 健壮性 收敛性
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