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Zeno and the Wrong Understanding of Motion—A Philosophical-Mathematical Inquiry into the Concept of Finitude as a Peculiarity of Infinity
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作者 Andreas Herberg-Rothe 《Journal of Applied Mathematics and Physics》 2024年第3期912-929,共18页
In contrast to the solutions of applied mathematics to Zeno’s paradoxes, I focus on the concept of motion and show that, by distinguishing two different forms of motion, Zeno’s apparent paradoxes are not paradoxical... In contrast to the solutions of applied mathematics to Zeno’s paradoxes, I focus on the concept of motion and show that, by distinguishing two different forms of motion, Zeno’s apparent paradoxes are not paradoxical at all. Zeno’s paradoxes indirectly prove that distances are not composed of extensionless points and, in general, that a higher dimension cannot be completely composed of lower ones. Conversely, lower dimensions can be understood as special cases of higher dimensions. To illustrate this approach, I consider Cantor’s only apparent proof that the real numbers are uncountable. However, his widely accepted indirect proof has the disadvantage that it depends on whether there is another way to make the real numbers countable. Cantor rightly assumes that there can be no smallest number between 0 and 1, and therefore no beginning of counting. For this reason he arbitrarily lists the real numbers in order to show with his diagonal method that this list can never be complete. The situation is different if we start with the largest number between 0 and 1 (0.999…) and use the method of an inverted triangle, which can be understood as a special fractal form. Here we can construct a vertical and a horizontal stratification with which it is actually possible to construct all real numbers between 0 and 1 without exception. Each column is infinite, and each number in that column is the starting point of a new triangle, while each row is finite. Even in a simple sine curve, we experience finiteness with respect to the y-axis and infinity with respect to the x-axis. The first parts of this article show that Zeno’s assumptions contradict the concept of motion as such, so it is not surprising that this misconstruction leads to contradictions. In the last part, I discuss Cantor’s diagonal method and explain the method of an inverted triangle that is internally structured like a fractal by repeating this inverted triangle at each column. The consequence is that we encounter two very different methods of count 展开更多
关键词 Zeno False Assumptions about Motion Finitude INFINITY Cantor’s Diagonal Method Inverted Triangle as a Different Method Vertical and Horizontal Dimensions Quantum Theory Relativity of Space and Time depending on Velocity
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大豆光合生理生态的研究——第16报 去荚对大豆比叶重和光合速率的影响 被引量:3
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作者 苗以农 许守民 +3 位作者 姜艳秋 杨文杰 朱长甫 刘学军 《大豆科学》 CAS CSCD 北大核心 1993年第1期70-74,共5页
大豆生殖生长时期,去荚植株的比叶重随生育进程增加的幅度较大,但叶片光合速率和全N含量(%)在去荚后短期内低于对照,随后尤其R_7和R_8期则显著高于对照。去荚延缓了叶片衰老,提高鼓粒末期叶片的光合速率和光呼吸速率。 荚果生长在一定... 大豆生殖生长时期,去荚植株的比叶重随生育进程增加的幅度较大,但叶片光合速率和全N含量(%)在去荚后短期内低于对照,随后尤其R_7和R_8期则显著高于对照。去荚延缓了叶片衰老,提高鼓粒末期叶片的光合速率和光呼吸速率。 荚果生长在一定时间内确能提高叶片光合速率,鼓粒末期叶片光合速率的明显降低是衰老的主要征状之一。 展开更多
关键词 大豆 比叶重 光合速率
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About One-Dimensional Conservative Systems with Position Depending Mass 被引量:2
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作者 Gustavo López Velázquez Carlos Rodrigo Martínez Prieto 《Journal of Modern Physics》 2014年第9期900-907,共8页
For a one-dimensional conservative system with position depending mass, one deduces consistently a constant of motion, a Lagrangian, and a Hamiltonian for the nonrelativistic case. With these functions, one shows the ... For a one-dimensional conservative system with position depending mass, one deduces consistently a constant of motion, a Lagrangian, and a Hamiltonian for the nonrelativistic case. With these functions, one shows the trajectories on the spaces (x,v) and (x,p) for a linear position depending mass. For the relativistic case, the Lagrangian and Hamiltonian cannot be given explicitly in general. However, we study the particular system with constant force and mass linear dependence on the position where the Lagrangian can be found explicitly, but the Hamiltonian remains implicit in the constant of motion. 展开更多
关键词 MASS VARIABLE Systems CONSERVATIVE System POSITION depending MASS
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ASYMPTOTIC BEHAVIOR AND OSCILLATIONS OF SECOND ORDER DIFFERENCE EQUATIONS WITH DELAY DEPENDING ON THE UNKNOWN FUNCTION 被引量:1
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作者 罗交晚 井竹君 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2001年第3期398-406,共9页
The asymptotic behavior of the nonoscillatory solutions of the difference equations △[r(n)△x(n)]+f(n,x(n),x(r(n,x(n))))=0 is considered. In the case when f is a strongly sublinear (superlinear) function, conditions ... The asymptotic behavior of the nonoscillatory solutions of the difference equations △[r(n)△x(n)]+f(n,x(n),x(r(n,x(n))))=0 is considered. In the case when f is a strongly sublinear (superlinear) function, conditions for oscillations of (1) are also found. 展开更多
关键词 Difference equation of second order asymptotic behavior delay depending on the unknown function
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One Dimensional Conservative System with Quadratic Dissipation and Position Depending Mass
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作者 Gustavo V. López Erick S. Madrigal 《Journal of Modern Physics》 2022年第2期127-137,共11页
Forl a 1-D conservative system with a position depending mass within a dissipative medium, its effect on the body is to exert a force depending on the squared of its velocity, a constant of motion, Lagrangian, general... Forl a 1-D conservative system with a position depending mass within a dissipative medium, its effect on the body is to exert a force depending on the squared of its velocity, a constant of motion, Lagrangian, generalized linear momentum, and Hamiltonian are obtained. We apply these new results to the harmonic oscillator and pendulum under the characteristics mentioned about, obtaining their constant of motion, Lagrangian and Hamiltonian for the case when the body is increasing its mass. 展开更多
关键词 DISSIPATION Position Mass depending Constant of Motion HAMILTONIAN
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A Single Server Queue with Coxian-2 Service and One-Phase Vacation (M/C-2/M/1 Queue)
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作者 Zeyad R. Al-Rawi Khalid M. S. Al Shboul 《Open Journal of Applied Sciences》 2021年第6期766-774,共9页
In this paper, we study a single server queueing system with Coxian-2 service.  In Particular, we study M/C-2/M/1 queue with Coxian-2 service and exponential vacation. We assume that units (customers) arrive at t... In this paper, we study a single server queueing system with Coxian-2 service.  In Particular, we study M/C-2/M/1 queue with Coxian-2 service and exponential vacation. We assume that units (customers) arrive at the system one by one in a Poisson process and the server provides one-by-one service based on first in first out (FIFO) rule. We obtained the steady state queue size distributions in terms of the probability generating functions, the average number of customers and their average waiting time in the system as well as in the queue. 展开更多
关键词 Single Server Queues Poisson Arrivals Coxian-2 Distribution Time depending Solution Steady State Solution
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MULTIPLE SOLUTIONS TO SINGULAR BVPS WITH VARIABLE COEFFICIENT ON THE HALF-LINE
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作者 Sma?l Djebali Samira Zahar 《Annals of Differential Equations》 2013年第3期324-337,共14页
This paper is concerned with a singular second-order nonlinear boundary value problem with a time depending on derivative operator and posed on the positive half-line. The nonlinearity is derivative-dependent, which h... This paper is concerned with a singular second-order nonlinear boundary value problem with a time depending on derivative operator and posed on the positive half-line. The nonlinearity is derivative-dependent, which has singularities at t=0 and/or x=0, and may change sign. The method of the upper and lower solutions on unbounded domains combined with the topological degree theory are employed to prove the existence and multiplicity of solutions. 展开更多
关键词 lower and upper solution infnity interval sign changing nonlinearity variable coefcient derivative depending nonlinearity singularity Nagumo condition MULTIPLICITY
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Size Depending Separation of HAP:Eu Nanoparticles in Dispersed Sol
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作者 I W Bauer 李世普 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第B12期198-200,共3页
The panicle size has a strong impact on the interactions between nanoparticles and cells. However, the synthesis process of nanoparticles limits the range of achievable average panicle sizes. When biocompatible hydrox... The panicle size has a strong impact on the interactions between nanoparticles and cells. However, the synthesis process of nanoparticles limits the range of achievable average panicle sizes. When biocompatible hydroxyapatite nanoparticles (HAP) are doped with the luminescent rare earth elemeat Europium (Eu), the panicle size becomes larger compared to pure HAP. Hence, a panicle size reduction is necessary to achieve similar experimental conditions when stbstituting pure HAP with luminescent HAP : Eu nanoparticles to investigate particlecell-interactions in cell culture experiments. While the sedimentation process of particles in liquids and gels has been well described in literature, the separation of particles in dispersed colloids has not been studied, yet. In this study, the size depending separation and particle size redaction of a homogeneous dispersed nanoparticle sol by gravity and centrifugation were investigated. As the results showed, shorter time of centrifugation at higher speed can reduce the average particle size compared to the decline of the panicle concentation in the upper sol layer most efficiently. This ceatrifugation method has some similarity to the overspeeding technique which is commonly used to lower the transient time to reach the equilibrium of sedimentation. 展开更多
关键词 NANOPARTICLES size depending separation CENTRIFUGE hydroxyapatite EUROPIUM
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Analytical Approximation to the Dynamics of a Binary Stars System with Time Depending Mass Variation
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作者 Gustavo V. López Elkin L. López 《Journal of Applied Mathematics and Physics》 2018年第3期613-619,共7页
We study the classical dynamics of binary stars when there is an interchange of mass between them. Assuming that one of the stars is more massive than others, the dynamics of the lighter one is analyzed as a function ... We study the classical dynamics of binary stars when there is an interchange of mass between them. Assuming that one of the stars is more massive than others, the dynamics of the lighter one is analyzed as a function of its time depending mass variation. Within our approximations and models for mass transference, we obtain a general result which establishes that if the lightest star looses mass, its period increases. If the lightest star wins mass, its period decreases. 展开更多
关键词 BINARY STARS TIME depending MASS PERIOD of BINARY STARS
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THE INTEGRAL AS A FUNCTlON OF THE UPPER LIMIT AND DEPENDING ON A PARAMETER TO SOLVE DRAWING THROUGH IDLING ROLLS
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作者 赵德文 赵志业 张强 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第1期93-100,共8页
The relocity and sirain-rate .field which are different from Avilzur's have beenestablished in Caitesian coordinates. Using the integral as a function of the upper limitand integration depending on a parameler, an... The relocity and sirain-rate .field which are different from Avilzur's have beenestablished in Caitesian coordinates. Using the integral as a function of the upper limitand integration depending on a parameler, an analylical upper-bound solution todrawing stress through idling rolls has been obtained in this paper. 展开更多
关键词 drawing through idling rolls integral as a function of theupper limit. integration depending on a parameter analyticalsolution
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Reaction Subdiffusion with Random Waiting Time Depending on the Preceding Jump Length
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作者 Hong Zhang Guo-Hua Li 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第9期19-23,共5页
To describe the energy-dependent characteristics of the reaction-subdiffusion process, we analyze the simple reaction A--→B under subdiffsion with waiting time depending on the preceding jump length, and derive the c... To describe the energy-dependent characteristics of the reaction-subdiffusion process, we analyze the simple reaction A--→B under subdiffsion with waiting time depending on the preceding jump length, and derive the corresponding master equations in the Fourier Laplace space for the distribution of A and B particles in a continuous time random walk scheme. Moreover, the generalizations of the reaction-diffusion equation for the Gaussian jump length with the probability density function of waiting time being quadratically dependent on the preceding jump length are obtained by applying the derived master equations. 展开更多
关键词 RDE Reaction Subdiffusion with Random Waiting Time depending on the Preceding Jump Length LENGTH
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大写的“女”字——二十世纪90年代女性文学片论
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作者 林晓华 邱艳萍 《楚雄师范学院学报》 2004年第6期56-58,共3页
在二十世纪 90年代的女性写作中, 无论是陈染们的疏离现实图景、沉溺于自我世界, 还是卫慧们在开放中对自我欲望的暴露, 她们的写作姿态都注重凸现女性性别意识, 从而构成了对男性主流社会的背离与颠覆, 并深化了文学对人自身的生命意... 在二十世纪 90年代的女性写作中, 无论是陈染们的疏离现实图景、沉溺于自我世界, 还是卫慧们在开放中对自我欲望的暴露, 她们的写作姿态都注重凸现女性性别意识, 从而构成了对男性主流社会的背离与颠覆, 并深化了文学对人自身的生命意识和生存处境的多向度的关照与表现。 展开更多
关键词 90女性文学 性别意识 颠覆 深化
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Depending on a Diaspora
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作者 Aggrey Mutambo 《ChinAfrica》 2013年第9期32-33,共2页
Somalia's rebirth relies greatly on the return of its many refugees MOGADISHU is on the mend and on the rise.A booming construction industry is building high-rise blocks that compete for skyline dominance,shops are o... Somalia's rebirth relies greatly on the return of its many refugees MOGADISHU is on the mend and on the rise.A booming construction industry is building high-rise blocks that compete for skyline dominance,shops are opening up at a much faster rate than two years earlier and airlines are launching routes to what has hitherto been considered the world's most dangerous city. Despite a rise in the number of ambushes,assassinations and suicide bombings in the city in August,a sign that Somali militant group Al-Shabaab has renewed its campaign to bring instability to the nation's capital,a sense of optimism still abounds as the country slowly makes its way back into the international arena.The United Kingdom has reopened its embassy after a 22-year closure. 展开更多
关键词 depending on a Diaspora
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依附——自主:人格的艰难涅槃——对20世纪中国市民文学一个侧面的剖示
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作者 田中阳 杨荣 《湖南大学学报(社会科学版)》 2003年第6期80-85,共6页
在20世纪中国市民文学的发展过程中,对自主人格的呼唤,对依附人格的批判,构成它最具深度的矛盾冲突线。20世纪市民文学展现的人格冲突,最体现市民文化价值观"蜕变的尴尬"。在世纪初和世纪末的官场现实主义小说中,对依附人格... 在20世纪中国市民文学的发展过程中,对自主人格的呼唤,对依附人格的批判,构成它最具深度的矛盾冲突线。20世纪市民文学展现的人格冲突,最体现市民文化价值观"蜕变的尴尬"。在世纪初和世纪末的官场现实主义小说中,对依附人格的批判和剖析即成为主导倾向。鸳蝴派的作品受西方个性解放思想影响颇多,但封建的伦理观念也深驻难移。海派作家叙事的平民立场、"俗人"立场体现了他们一种平等自由的价值观念,但他们笔下也没有站立起一个健康的具有自主人格的新人形象。新写实小说、70年代作家、美女作家等八九十年代的市民文学所展示的市民的人格世界也是灰色的。张欣笔下的"城市丽人",在残酷的竞争中开始掌握自己的命运,开始锻冶出一种新的人格,这是百年市民文学的一个终点,也是新的世纪市民文学的一个起点。 展开更多
关键词 依附 自主 人格 涅槃
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产业集群区位选择形成机制分析 被引量:34
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作者 于树江 李艳双 《中国软科学》 CSSCI 北大核心 2004年第4期120-122,119,共4页
本文在对产业集群理论主要研究领域进行总结的基础上,重点分析了产业集群区位选择的形成机制,主要包括区位的成本限制、区位选择的路径依赖性及空间吸聚作用机理等内容,并结合国外的实证调查,揭示了不同区位条件对产业集群创新的影响。
关键词 产业集群 区位选择 成本 产业创新 路径依赖
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凉血解毒、清热化湿和凉血解毒、健脾温阳法治疗慢性重型肝炎的临床观察 被引量:43
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作者 孙克伟 陈斌 +2 位作者 黄裕红 伍玉南 周小青 《中国中西医结合杂志》 CAS CSCD 北大核心 2006年第11期981-983,共3页
目的观察凉血解毒、清热化湿法(简称清热化湿法)和凉血解毒、健脾温阳法(简称健脾温阳法)治疗慢性重型肝炎阴阳黄证的初步疗效,为黄疸的中医治疗提供思路。方法采用随机、对照方法,进行中医辨证治疗慢性重型肝炎43例,重点观察比较清热... 目的观察凉血解毒、清热化湿法(简称清热化湿法)和凉血解毒、健脾温阳法(简称健脾温阳法)治疗慢性重型肝炎阴阳黄证的初步疗效,为黄疸的中医治疗提供思路。方法采用随机、对照方法,进行中医辨证治疗慢性重型肝炎43例,重点观察比较清热化湿、健脾温阳两法消退黄疸的作用。结果治疗4周后,清热化湿组22例,有效16例(72·7%),无效6例(27·3%);健脾温阳组21例,有效19例(90·5%),无效2例(9·5%);两组疗效比较差异无显著性。TBIL:治疗后两组均下降(P<0·01),且健脾温阳组下降的幅度大于清热化湿组(P<0·05);凝血酶原活动度:健脾温阳组上升幅度优于清热化湿组(P<0·05);ALT:两组均降低(P<0·05),但两组间比较差异无显著性。结论凉血解毒、健脾温阳法治疗慢性重型肝炎阴阳黄证的疗效优于凉血解毒、清热化湿法。 展开更多
关键词 慢性重型肝炎 阴阳黄证 辨证治疗 消退黄疸
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中医辨证施治结合化疗对中晚期非小细胞肺癌预后因子的影响 被引量:37
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作者 李柳宁 刘伟胜 +5 位作者 徐凯 吴万垠 刘宇龙 朱迪盈 罗海英 陈春永 《中国中西医结合杂志》 CAS CSCD 北大核心 2003年第8期575-579,共5页
目的 :观察中医辨证施治结合化疗对中晚期非小细胞肺癌预后因子的影响。方法 :将 12 0例中晚期非小细胞肺癌患者随机分为 3组。中医组予以中医辨证施治 (抗肿瘤中药静脉制剂、消积饮、辨证中药汤剂 )、一般支持治疗及对症处理 ;西医组... 目的 :观察中医辨证施治结合化疗对中晚期非小细胞肺癌预后因子的影响。方法 :将 12 0例中晚期非小细胞肺癌患者随机分为 3组。中医组予以中医辨证施治 (抗肿瘤中药静脉制剂、消积饮、辨证中药汤剂 )、一般支持治疗及对症处理 ;西医组予以化疗、一般支持治疗及对症处理 ;中西医组予以中医辨证施治结合化疗、一般支持治疗及对症处理。并通过卡卜兰 迈尔 (Kaplan Meier)法统计分析各组的远期疗效 ,用COX回归模型多因素分析影响生存率的 2 4个预后因子 ,筛选危险因素及保护因素。结果 :中位生存期中医组为 (2 85 0 0± 17 92 )天 ,西医组为 (2 6 5 0 0± 1 80 )天 ,两组比较差异无显著性 (P >0 0 5 ) ,中西医组为(35 9 0 0± 7 0 0 )天 ,与中医组及西医组比较 ,差异有显著性 (P <0 0 5 )。 0 5、1年生存率 (% )中医组分别为84 4、18 1;西医组为 82 5、2 0 6 ;中西医组为 92 5、4 2 7。中西医组与中医组、西医组 1年生存率比较 ,差异均有显著性 (P <0 0 5 )。 2 4个预后因子经COX回归模型多因素分析 ,临床分期、淋巴结受累、并发症、中医证候分类、治疗前Karnofsky评分、乳酸脱氢酶、癌胚抗原、CA199、治疗方式、治疗后生存量表总积分、治疗稳定、CD3+ 等因素对生存率的影响 ,差异均有显著性 展开更多
关键词 肺癌 中西医结合治疗 中医辨证施治 化学治疗 预后
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如何做新结构经济学的研究 被引量:28
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作者 林毅夫 《上海大学学报(社会科学版)》 CSSCI 北大核心 2020年第2期1-18,共18页
文章从什么是新结构经济学,什么是新结构经济学的研究为切入点来探讨如何进行新结构经济学的研究,提出在进行新结构经济学的研究时应该遵循的五个原则:首先,要从现象出发,而非从现有的理论出发来进行研究。第二,在面对一个现象时要秉持... 文章从什么是新结构经济学,什么是新结构经济学的研究为切入点来探讨如何进行新结构经济学的研究,提出在进行新结构经济学的研究时应该遵循的五个原则:首先,要从现象出发,而非从现有的理论出发来进行研究。第二,在面对一个现象时要秉持“常无”的心态,避免对号入座。第三,要回归到亚当·斯密所用的研究方法,也就是对所要解释的现象的“本质和决定因素的探索”。第四,现象总有特殊性,理论研究则要从特殊性上升到现象背后的一般性。第五,要了解不同发展程度国家结构的差异性和内生性,把现有的根据发达国家的经验现象总结的以发达国家的结构为给定结构的二维经济学变为不同发展程度国家有不同结构的三维经济学,以理论建模和数据检验来探索理论框架扩维以后的新视角、新见解。 展开更多
关键词 新结构经济学 新结构经济学研究 要素禀赋 “常无” 结构革命
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变荷载下饱和软黏土一维大应变固结解析理论 被引量:19
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作者 谢康和 郑辉 C J Leo 《水利学报》 EI CSCD 北大核心 2003年第10期6-13,共8页
基于软黏土一维非线性大应变固结基本理论,建立了能考虑荷载变化、土层自重等因素影响的拉格朗日坐标下以超静孔压u为变量的一维大应变固结控制方程,并通过对土体压缩性和渗透性的假定获得了方程的解析解。基于此解,分析了单级等速加荷... 基于软黏土一维非线性大应变固结基本理论,建立了能考虑荷载变化、土层自重等因素影响的拉格朗日坐标下以超静孔压u为变量的一维大应变固结控制方程,并通过对土体压缩性和渗透性的假定获得了方程的解析解。基于此解,分析了单级等速加荷条件下软黏土一维大应变固结性状。从中可见,大应变固结过程中土体变形的发展要快于超静孔压的消散;荷载增大,超静孔压消散趋慢;加荷速率越大,土体固结越快;考虑土层自重影响时孔隙比的分布更为合理。此外,本文的解析解也可用于验证各种大应变固结数值解法的正确性。 展开更多
关键词 饱和软黏土 变荷载 非线性 大应变 一维固结 解析理论
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新型冠状病毒肺炎中医病理研究 被引量:22
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作者 张云飞 赵鹏飞 沈体雁 《中医学报》 CAS 2020年第4期694-698,共5页
鉴于新型冠状病毒肺炎"病位在肺,属于疫病",其中医名可为"肺疫"。新冠肺疫的病因,外因之主因是感染病毒(异气),内因是患者身体系统,同时合并兼夹感受"六淫"邪气(常气)。只有疫毒本身是普遍的,寒暑燥湿风... 鉴于新型冠状病毒肺炎"病位在肺,属于疫病",其中医名可为"肺疫"。新冠肺疫的病因,外因之主因是感染病毒(异气),内因是患者身体系统,同时合并兼夹感受"六淫"邪气(常气)。只有疫毒本身是普遍的,寒暑燥湿风火不具有普遍性,是因时、因地、因人而变的。常见病机是邪毒犯肺,挟热下利,肺失宣降,水停生湿。总体治则是扶正祛邪、平衡阴阳、标本兼治、三因制宜。此外,本文还提出病毒有无寒热属性的问题,供医学界共同探讨。 展开更多
关键词 新型冠状病毒肺炎 “肺疫” 肺失宣降 三因制宜 新型冠状病毒
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