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Four Dimensions of Integrating Chinese Culture Into College English Teaching From the Perspective of Tyler’s Basic Principles
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作者 CHEN Lijuan 《Sino-US English Teaching》 2024年第5期232-237,共6页
Integrating Chinese culture into college English can not only enhance students’humanities literacy and cultivate their cultural confidence,but also facilitate the inheritance and international dissemination of Chines... Integrating Chinese culture into college English can not only enhance students’humanities literacy and cultivate their cultural confidence,but also facilitate the inheritance and international dissemination of Chinese culture.Taking Tyler’s curriculum framework as the starting point,this paper analyzes some factors that affect the integration of Chinese culture into the college English teaching and proposes some strategies for the integration of Chinese culture into college English teaching by innovating teaching objectives,enriching teaching contents,transforming modes of course delivery,and reconstructing the assessment system. 展开更多
关键词 Tyler’s basic principles Chinese culture college English
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From Generalized Hamilton Principle to Generalized Schrodinger Equation
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作者 Xiangyao Wu Benshan Wu +1 位作者 Hong Li Qiming Wu 《Journal of Modern Physics》 CAS 2023年第5期676-691,共16页
The Hamilton principle is a variation principle describing the isolated and conservative systems, its Lagrange function is the difference between kinetic energy and potential energy. By Feynman path integration, we ca... The Hamilton principle is a variation principle describing the isolated and conservative systems, its Lagrange function is the difference between kinetic energy and potential energy. By Feynman path integration, we can obtain the standard Schrodinger equation. In this paper, we have given the generalized Hamilton principle, which can describe the heat exchange system, and the nonconservative force system. On this basis, we have further given their generalized Lagrange functions and Hamilton functions. With the Feynman path integration, we have given the generalized Schrodinger equation of nonconservative force system and the heat exchange system. 展开更多
关键词 Generalized hamilton principle Nonconservative systems Thermodynamic system Generalized schrodinger Equation
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High-Order Hamilton's Principle and the Hamilton's Principle of High-Order Lagrangian Function 被引量:2
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作者 ZHAO Hong-Xia MA Shan-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第2期297-302,共6页
In this paper, based on the theorem of the high-order velocity energy, integration and variation principle, the high-order Hamilton's principle of general holonomic systems is given. Then, three-order Lagrangian equa... In this paper, based on the theorem of the high-order velocity energy, integration and variation principle, the high-order Hamilton's principle of general holonomic systems is given. Then, three-order Lagrangian equations and four-order Lagrangian equations are obtained from the high-order Hamilton's principle. Finally, the Hamilton's principle of high-order Lagrangian function is given. 展开更多
关键词 hamilton's principle high-order velocity energy integration and variation principle Lagrangian function
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From Black Holes to Information Erasure: Uniting Bekenstein’s Bound and Landauer’s Principle
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2023年第8期2185-2194,共10页
This research aims to integrate Bekenstein’s bound and Landauer’s principle, providing a unified framework to understand the limits of information and energy in physical systems. By combining these principles, we ex... This research aims to integrate Bekenstein’s bound and Landauer’s principle, providing a unified framework to understand the limits of information and energy in physical systems. By combining these principles, we explore the implications for black hole thermodynamics, astrophysics, astronomy, information theory, and the search for new laws of nature. The result includes an estimation of the number of bits stored in a black hole (less than 1.4 × 10<sup>30</sup> bits/m<sup>3</sup>), enhancing our understanding of information storage in extreme gravitational environments. This integration offers valuable insights into the fundamental nature of information and energy, impacting scientific advancements in multiple disciplines. 展开更多
关键词 Astrophysics and Astronomy Bekenstein Bound Black Hole Thermodynamics Information and Energy Limits Information Theory and Quantum Mechanics Landauer’s principle
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Constrained Hamilton variational principle for shallow water problems and Zu-class symplectic algorithm 被引量:2
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作者 Feng WU Wanxie ZHONG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第1期1-14,共14页
In this paper, the shallow water problem is discussed. By treating the incompressible condition as the constraint, a constrained Hamilton variational principle is presented for the shallow water problem. Based on the ... In this paper, the shallow water problem is discussed. By treating the incompressible condition as the constraint, a constrained Hamilton variational principle is presented for the shallow water problem. Based on the constrained Hamilton variational principle, a shallow water equation based on displacement and pressure (SWE-DP) is developed. A hybrid numerical method combining the finite element method for spa- tial discretization and the Zu-class method for time integration is created for the SWE- DP. The correctness of the proposed SWE-DP is verified by numerical comparisons with two existing shallow water equations (SWEs). The effectiveness of the hybrid numerical method proposed for the SWE-DP is also verified by numerical experiments. Moreover, the numerical experiments demonstrate that the Zu-class method shows excellent perfor- mance with respect to simulating the long time evolution of the shallow water. 展开更多
关键词 shallow water equation sWE) constrained hamilton variational principle Zu-class method
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A hybrid-stress element based on Hamilton principle 被引量:2
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作者 Song Cen Tao Zhang +2 位作者 Chen-Feng Li Xiang-Rong Fu Yu-Qiu Long 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第4期625-634,共10页
A novel hybrid-stress finite element method is proposed for constructing simple 4-node quadrilateral plane elements, and the new element is denoted as HH4-3fl here. Firstly, the theoretical basis of the traditional hy... A novel hybrid-stress finite element method is proposed for constructing simple 4-node quadrilateral plane elements, and the new element is denoted as HH4-3fl here. Firstly, the theoretical basis of the traditional hybrid-stress elements, i.e., the Hellinger-Reissner variational principle, is replaced by the Hamilton variational principle, in which the number of the stress variables is reduced from 3 to 2. Secondly, three stress parameters and corresponding trial functions are introduced into the system equations. Thirdly, the displacement fields of the conventional bilinear isoparametric element are employed in the new models. Finally, from the stationary condition, the stress parameters can be expressed in terms of the displacement parameters, and thus the new element stiffness matrices can be obtained. Since the required number of stress variables in the Hamilton variational principle is less than that in the Hellinger-Reissner variational principle, and no additional incompatible displacement modes are considered, the new hybrid-stress element is simpler than the traditional ones. Furthermore, in order to improve the accuracy of the stress solutions, two enhanced post-processing schemes are also proposed for element HH4-3β. Numerical examples show that the proposed model exhibits great improvements in both displacement and stress solutions, implying that the proposed technique is an effective way for developing simple finite element models with high performance. 展开更多
关键词 Finite element hamilton variational principle Hybrid-stress element Post-processing schemes
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UNCONVENTIONAL HAMILTON-TYPE VARIATIONAL PRINCIPLES FOR DYNAMICS OF REISSNER SANDWICH PLATE 被引量:1
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作者 黄伟江 罗恩 佘慧 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第1期75-82,共8页
According to the basic idea of classical yin-yang complementarity and modern dual-complementarity, in a simple and unified way proposed by Luo(1987), some uncon ventional Hamilton-type variational principles for dyn... According to the basic idea of classical yin-yang complementarity and modern dual-complementarity, in a simple and unified way proposed by Luo(1987), some uncon ventional Hamilton-type variational principles for dynamics of Reissner sandwich plate can be established systematically. The unconventional Hamilton-type variation principle can fully characterize the initial boundary value problem of this dynamics. In this paper, an important integral relation is given, which can be considered as the generalized principle of virtual work in mechanics. Based on this relation, it is possible not only to obtain the principle of virtual work in dynamics of Reissner sandwich plate, but also to derive systematically the complementary functionals for fivefield, two-field and one-field unconventional Hamilton-type variational principles by the generalized Legender transformations. Furthermore, with this approach, the intrinsic relationship among the various principles can be explained clearly. 展开更多
关键词 unconventional hamilton-type variational principle Reissner sandwich plate DYNAMICs dual-complementary relation initial-boundary-value problem
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The Hamilton System and Hamilton Type Generalized Variational Principle for the Laminated Composite Plates and Shells
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作者 邹贵平 梁岗 《Advances in Manufacturing》 SCIE CAS 1997年第2期123-129,共7页
By introducing the Hamilton theory and algorithms into the problems of laminated composite plates andshells, the Hamiltion type generalized variational principle is established, and the Hamilton canonical equations an... By introducing the Hamilton theory and algorithms into the problems of laminated composite plates andshells, the Hamiltion type generalized variational principle is established, and the Hamilton canonical equations andthe boundary conditions for the static and elastoplastic analysis of composite plates are presented. With thetransformation of phase variables, the Hamilton canonical equations and their boundary conditions for thecylindrical shells and doubly curved shells in the curvilinear coordinate are given. 展开更多
关键词 laminated composite plates and shells hamilton canonical equations hamilton type generalizedvariational principle symplectic geometry
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Unconventional Hamilton-type variational principles for nonlinear elastodynamics of orthogonal cable-net structures
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作者 李纬华 罗恩 黄伟江 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第7期931-942,共12页
According to the basic idea of classical yin-yang complementarity and modem dual-complementarity, in a simple and unified new way proposed by Luo, the unconventional Hamilton-type variational principles for geometrica... According to the basic idea of classical yin-yang complementarity and modem dual-complementarity, in a simple and unified new way proposed by Luo, the unconventional Hamilton-type variational principles for geometrically nonlinear elastodynamics of orthogonal cable-net structures are established systematically, which can fully characterize the initial-boundary-value problem of this kind of dynamics. An ifnportant integral relation is made, which can be considered as the generalized principle of virtual work for geometrically nonlinear dynamics of orthogonal cable-net structures in mechanics. Based on such relationship, it is possible not only to obtain the principle of virtual work for geometrically nonlinear dynamics of orthogonal cable-net structures, but also to derive systematically the complementary functionals for five-field, four-field, three-field and two-field unconventional Hamilton-type variational principles, and the functional for the unconventional Hamilton-type variational principle in phase space and the potential energy functional for one-field unconventional Hamilton-type variational principle for geometrically nonlinear elastodynamics of orthogonal cable-net structures by the generalized Legendre transformation given in this paper, Furthermore, the intrinsic relationship among various principles can be explained clearly with this approach. 展开更多
关键词 unconventional hamilton-type variational principle geometric nonlinearity ELAsTODYNAMICs orthogonal cable-net structures dual-complementary relation initialboundary-value problem phase space
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Predicting H2S Oxidative Dehydrogenation over Graphene Oxides from First Principles
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作者 黄斌 陈碧波 陈荣 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第2期143-149,I0001,共8页
Spin-polarized periodic density functional theory was performed to characterize H2S adsorp- tion and dissociation on graphene oxides (GO) surface. The comprehensive reaction network of H2S oxidation with epoxy and h... Spin-polarized periodic density functional theory was performed to characterize H2S adsorp- tion and dissociation on graphene oxides (GO) surface. The comprehensive reaction network of H2S oxidation with epoxy and hydroxyl groups of GO was discussed. It is shown that the reduction reaction is mainly governed by epoxide ring opening and hydroxyl hydrogenation which is initiated by H transfer from H2S or its derivatives, hlrthermore, the presence of another OH group at the opposite side relative to the adsorbed H2S activates the oxygen group to facilitate epoxide ring opening and hydroxyl hydrogenation. For H2S interaction with -O and -OH groups adsorption on each side of graphene, the pathway is a favorable reaction path by the introduction of intermediate states, the predicted energy barriers are 3.2 and 10.4 kcal/mol, respectively, the second H transfer is tile rate-determining step in the whole reaction process. In addition, our calculations suggest that both epoxy and hydroxyl groups can enhance tile binding of S to the C-C bonds and the effect of hydroxyl group is more local than that of the epoxy. 展开更多
关键词 First principles H2s ADsORPTION DIssOCIATION
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湿气环境中CO_(2)-H_(2)S在α-Fe(110)密排面上吸附与点蚀机理研究
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作者 李金灵 马文骏 +2 位作者 朱世东 屈撑囤 付安庆 《表面技术》 EI CAS CSCD 北大核心 2024年第20期82-93,共12页
目的从微观尺度探究CO_(2)-H_(2)S(CO_(2)和H_(2)S共存)在湿气管道顶部的吸附特性,进而揭示点蚀机理。方法基于密度泛函理论的第一性原理,利用Materials Studio构建CO_(2)、H_(2)S和CO_(2)-H_(2)S在α-Fe(110)密排面的吸附模型,对CO_(2)... 目的从微观尺度探究CO_(2)-H_(2)S(CO_(2)和H_(2)S共存)在湿气管道顶部的吸附特性,进而揭示点蚀机理。方法基于密度泛函理论的第一性原理,利用Materials Studio构建CO_(2)、H_(2)S和CO_(2)-H_(2)S在α-Fe(110)密排面的吸附模型,对CO_(2)、H_(2)S和CO_(2)-H_(2)S在α-Fe(110)面的吸附能、局域态密度、分波态密度和差分电荷密度进行仿真;利用高温高压釜模拟CO_(2)-H_(2)S-Cl^(-)腐蚀环境,分析L360钢在湿气环境中的腐蚀行为;最后,揭示含Cl^(-)湿气管道顶部CO_(2)-H_(2)S吸附机制与点蚀机理。结果CO_(2)、H_(2)S、CO_(2)-H_(2)S及CO_(2)-H_(2)S-Cl^(-)在最稳定位置时的吸附能分别为-4.065、-3.961、-8.538、-12.775e V,表明相较于CO_(2)与H_(2)S单独吸附,CO_(2)-H_(2)S在α-Fe(110)面的吸附能更负,Cl^(-)会进一步降低CO_(2)-H_(2)S的吸附能;且CO_(2)在与H_(2)S竞争环境电子中占优势;Cl^(-)会使CO_(2)-H_(2)S的局域态密度峰值降低,转移趋势为失去电子,基体和腐蚀介质的电子向着低能级跃迁释放出更多能量,进而加强了Fe与CO_(2)-H_(2)S间的化学键强度;Cl^(-)的2p轨道与Fe的3d轨道在-6.8 eV和-5.7 eV发生重叠,Cl^(-)被吸附到Fe表面并与Fe形成化学键生成氯化物,进而改变腐蚀产物膜的组分与结构,削弱产物膜的致密性和稳定性,减弱腐蚀阻抗力。在含Cl^(-)湿气的CO_(2)-H_(2)S环境中,液相中的Cl^(-)浓度升高,使L360钢的气相平均腐蚀速率逐渐增大,最高达2.935mm/a,点蚀越发严重。结论CO_(2)与H_(2)S在α-Fe(110)面吸附存在一定的协同和竞争作用,协同促进金属的腐蚀,FeCO3会优先沉积成膜,但H_(2)S会抑制FeCO3的生长,腐蚀产物以FeS为主;Cl^(-)会增强CO_(2)-H_(2)S与α-Fe(110)面间的作用力,弱化腐蚀产物膜层的保护性,进一步加速金属腐蚀、尤其是点蚀。 展开更多
关键词 CO_(2)-H_(2)s Cl^(-) 第一性原理 α-Fe(110)密排面 吸附特征 腐蚀机理
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S-T-S混合式循环互助教学模式用于少学时“化工原理”课程
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作者 吕玲 《教育教学论坛》 2024年第31期157-160,共4页
“化工原理”课程是化工及相关专业的专业基础课程,相关专业的学时少,课程难,需重点解决的问题是“三多”“三不愿”“三不明”。针对痛点问题,提出了线上线下混合式循环互助的创新设计思路,包括:教师帮助学生自制课前、课中、课后习题... “化工原理”课程是化工及相关专业的专业基础课程,相关专业的学时少,课程难,需重点解决的问题是“三多”“三不愿”“三不明”。针对痛点问题,提出了线上线下混合式循环互助的创新设计思路,包括:教师帮助学生自制课前、课中、课后习题,学生帮助教师反馈真实学习情况,学生帮助学生组团互助学习。问卷调查和评教结果显示,在一定程度上解决了“三多”“三不愿”的问题;通过建立“助教团队”反馈不同层次学生的学习情况,较好地解决了“三不明”的问题。学生的成绩与教改前相比有明显提高。 展开更多
关键词 线上线下 s-T-s教学模式 化工原理 痛点问题
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A Good Example of Hemingway's Iceberg Principle:The Killers
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作者 庄新月 《海外英语》 2013年第4X期200-202,共3页
Hemingway established a well-known literary theory - iceberg principle.He said he always attempted to create his literary works according to this principle.In his opinion,if a prose writer has a pretty clear idea of w... Hemingway established a well-known literary theory - iceberg principle.He said he always attempted to create his literary works according to this principle.In his opinion,if a prose writer has a pretty clear idea of what he writes about,then he can omit the things he knows,and the readers will strongly feel that what the writer has omitted seems to have been written as long as what he writes is authentic.Hemingway himself once said,"The dignity of movement of an iceberg is due to only one eighth of it being above water."Here,one eighth refers to the information given by the author,and the rest refers to the unwrit ten information that can be acquired in readers'imagination on the basis of the one eighth.The Killers is a good example of Hemingway's iceberg principle.This essay will analyse the characters in it to show how the principle was used in this short story.With no doubt the iceberg principle leaves a large space for the readers to imagine and better understand Hemingway's works. 展开更多
关键词 Hemingway’s ICEBERG principle The Killers the CHAR
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H_(2)S在Cr(111)面上吸附与解离的第一性原理研究 被引量:1
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作者 江佐禹 黄本生 +1 位作者 何子涛 罗霞 《原子与分子物理学报》 CAS 北大核心 2024年第2期9-14,共6页
采用了第一性原理研究了H_(2)S在Cr(111)面的吸附解离过程,利用吸附能、吸附构型和偏态密度图(PDOS)研究了H_(2)S及其解离产物在Cr(111)面上的吸附情况,都偏向倾斜吸附在Cr(111)面.同时研究了HS/H和S/H共吸附情况,得到共吸附物质在Cr(1... 采用了第一性原理研究了H_(2)S在Cr(111)面的吸附解离过程,利用吸附能、吸附构型和偏态密度图(PDOS)研究了H_(2)S及其解离产物在Cr(111)面上的吸附情况,都偏向倾斜吸附在Cr(111)面.同时研究了HS/H和S/H共吸附情况,得到共吸附物质在Cr(111)面上有明显的相互作用.最后使用线性同步和二次同步变换方法确定了解离反应的过渡态,了解到第一、二步解离的活化能分别为1.65 eV、0.82 eV,H_(2)S分子在Cr(111)面上的解离过程是放热反应,反应能为-2.90 eV. 展开更多
关键词 H_(2)s Cr(111) 吸附 解离 第一性原理
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VECTORIAL EKELAND'S VARIATIONAL PRINCIPLE WITH A W-DISTANCE AND ITS EQUIVALENT THEOREMS 被引量:8
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作者 丘京辉 李博 贺飞 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2221-2236,共16页
By using the properties of w-distances and Gerstewitz's functions, we first give a vectorial Takahashi's nonconvex minimization theorem with a w-distance. From this, we deduce a general vectorial Ekeland's variatio... By using the properties of w-distances and Gerstewitz's functions, we first give a vectorial Takahashi's nonconvex minimization theorem with a w-distance. From this, we deduce a general vectorial Ekeland's variational principle, where the objective function is from a complete metric space into a pre-ordered topological vector space and the perturbation contains a w-distance and a non-decreasing function of the objective function value. From the general vectorial variational principle, we deduce a vectorial Caristfs fixed point theorem with a w-distance. Finally we show that the above three theorems are equivalent to each other. The related known results are generalized and improved. In particular, some conditions in the theorems of [Y. Araya, Ekeland's variational principle and its equivalent theorems in vector optimization, J. Math. Anal. Appl. 346(2008), 9-16] are weakened or even completely relieved. 展开更多
关键词 Takahashi's minimization theorem Ekeland's variational principle Caristi'sfixed point theorem Gerstewitz's function w-distance
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The Basic Principles of Kin Sociality and Eusociality: Human Evolution 被引量:7
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作者 Ding-Yu Chung 《Natural Science》 2016年第1期8-19,共12页
The paper posits that kin sociality and eusociality are derived from the handicap-care principles based on the need-based care to the handicappers from the caregivers for the self-interest of the caregivers. In this p... The paper posits that kin sociality and eusociality are derived from the handicap-care principles based on the need-based care to the handicappers from the caregivers for the self-interest of the caregivers. In this paper, handicap is defined as the difficulty to survive and reproduce independently. Kin sociality is derived from the childhood handicap-care principle where the children are the handicapped children who receive the care from the kin caregivers in the inclusive kin group to survive. The caregiver gives care for its self-interest to reproduce its gene. The individual’s gene of kin sociality contains the handicapped childhood and the caregiving adulthood. Eusociality is derived from the adulthood handicap-care principle where responsible adults are the handicapped adults who give care and receive care at the same time in the interdependent eusocial group to survive and reproduce its gene. Queen bees reproduce, but must receive care from worker bees that work but must rely on queen bees to reproduce. A caregiver gives care for its self-interest to survive and reproduce its gene. The individual’s gene of eusociality contains the handicapped childhood-adulthood and the caregiving adulthood. The chronological sequence of the sociality evolution is individual sociality without handicap, kin sociality with handicapped childhood, and eusociality with handicapped adulthood. Eusociality in humans is derived from bipedalism and the mixed habitat. The chronological sequence of the eusocial human evolution is 1) the eusocial early hominins with bipedalism and the mixed habitat, 2) the eusocial early Homo species with bipedalism, the larger brain, and the open habitat, 3) the eusocial late Homo species with bipedalism, the largest brain, and the unstable habitat, and 4) extended eusocial Homo sapiens with bipedalism, the shrinking brain, omnipresent imagination, and the harsh habitat. The omnipresence of imagination in human culture converts eusociality into extended eusociality with both perception and omnipresent imagination. 展开更多
关键词 Kin sociality EUsOCIALITY Evolution Kin selection Group selection The Handicap-Care principle Human Evolution sUPERNATURAL hamiltons Rule DOMEsTICATION shrinking Brain Upper Paleolithic Revolution
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Recent Advances on Herglotz’s Generalized Variational Principle of Nonconservative Dynamics 被引量:5
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作者 ZHANG Yi 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第1期13-26,共14页
This paper summarized the recent development on Herglotz’s generalized variational principle and its symmetries and conserved quantities for nonconservative dynamical systems.Taking Lagrangian mechanics,Hamiltonian m... This paper summarized the recent development on Herglotz’s generalized variational principle and its symmetries and conserved quantities for nonconservative dynamical systems.Taking Lagrangian mechanics,Hamiltonian mechanics and Birkhoffian mechanics as three research frames,we introduce Herglotz’s generalized variational principle,dynamical equations of Herglotz type,Noether symmetry and conserved quantities,and their generalization to time-delay dynamics,fractional dynamics and time-scale dynamics,and put forward some problems as suggestions for future research. 展开更多
关键词 nonconservative dynamics Herglotz’s generalized variational principle Lagrangian mechanics Hamil-tonian mechanics Birkhoffian mechanics
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Fractional Pfaff-Birkhoff Principle and Birkhoff′s Equations in Terms of Riesz Fractional Derivatives 被引量:3
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作者 周燕 张毅 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2014年第1期63-69,共7页
The dynamical and physical behavior of a complex system can be more accurately described by using the fractional model.With the successful use of fractional calculus in many areas of science and engineering,it is nece... The dynamical and physical behavior of a complex system can be more accurately described by using the fractional model.With the successful use of fractional calculus in many areas of science and engineering,it is necessary to extend the classical theories and methods of analytical mechanics to the fractional dynamic system.Birkhoffian mechanics is a natural generalization of Hamiltonian mechanics,and its core is the Pfaff-Birkhoff principle and Birkhoff′s equations.The study on the Birkhoffian mechanics is an important developmental direction of modern analytical mechanics.Here,the fractional Pfaff-Birkhoff variational problem is presented and studied.The definitions of fractional derivatives,the formulae for integration by parts and some other preliminaries are firstly given.Secondly,the fractional Pfaff-Birkhoff principle and the fractional Birkhoff′s equations in terms of RieszRiemann-Liouville fractional derivatives and Riesz-Caputo fractional derivatives are presented respectively.Finally,an example is given to illustrate the application of the results. 展开更多
关键词 fractional derivative fractional Pfaff-Birkhoff principle fractional Birkhoff′s equation transversality condition
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EKELAND'S PRINCIPLE FOR SET-VALUED VECTOR EQUILIBRIUM PROBLEMS 被引量:2
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作者 龚循华 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1179-1192,共14页
In this paper, we introduce a concept of quasi C-lower semicontinuity for setvalued mapping and provide a vector version of Ekeland's theorem related to set-valued vector equilibrium problems. As applications, we der... In this paper, we introduce a concept of quasi C-lower semicontinuity for setvalued mapping and provide a vector version of Ekeland's theorem related to set-valued vector equilibrium problems. As applications, we derive an existence theorem of weakly efficient solution for set-valued vector equilibrium problems without the assumption of convexity of the constraint set and the assumptions of convexity and monotonicity of the set-valued mapping. We also obtain an existence theorem of ε-approximate solution for set-valued vector equilibrium problems without the assumptions of compactness and convexity of the constraint set. 展开更多
关键词 Ekeland's principle set-valued vector equilibrium problems weakly efficient solution c-approximate solution EXIsTENCE
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用于低浓度H_(2)S室温稳定监测的CsPbBr_(3)@TiO_(2)异质结微晶气体传感器
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作者 逯江浩 黄胜 +4 位作者 陈露 程永超 高莎莎 陶雪钰 顾修全 《人工晶体学报》 CAS 北大核心 2024年第10期1815-1826,共12页
通过简单的溶液法用TiO(Acac)_(2)原位包覆CsPbBr_(3)全无机钙钛矿材料,在400℃加热后直接制成了CsPbBr_(3)@TiO_(2)核壳结构微晶,使用X射线衍射(XRD)、扫描电子显微镜(SEM)、高倍透射电子显微镜(HRTEM)及X射线光电子能谱(XPS)对CsPbBr_... 通过简单的溶液法用TiO(Acac)_(2)原位包覆CsPbBr_(3)全无机钙钛矿材料,在400℃加热后直接制成了CsPbBr_(3)@TiO_(2)核壳结构微晶,使用X射线衍射(XRD)、扫描电子显微镜(SEM)、高倍透射电子显微镜(HRTEM)及X射线光电子能谱(XPS)对CsPbBr_(3)@TiO_(2)微晶的晶体结构、微观形貌、化学组成进行表征。结果表明,原位金属氧化物包覆钙钛矿形成分散良好、大小为4~8μm的球壳结构。用旋涂法在掺氟氧化锡(FTO)电极上构筑了CsPbBr_(3)@TiO_(2)薄膜气体传感器,在室温下测试其对H_(2)S气体的检测灵敏度,结果发现,该传感器对H_(2)S气体的检测下限达25 ppb(1 ppb=10-9),对100 ppb H_(2)S响应/恢复时间为24/21 s,灵敏度为0.59,响应曲线具有良好的循环稳定性。另外,传感器暴露在空气中30 d内的稳定性高于90%,且具有优异的气体选择性和抗湿度干扰性。通过光致发光(PL)光谱、时间分辨光致发光(TRPL)光谱、紫外-可见漫反射光谱(UV-Vis)及紫外光电子能谱(UPS)测试分析了其能带位置、电荷动力学和配位机理,并用氧吸附原理对其传感机理进行了解释。该工作为室温下低浓度H_(2)S气体的稳定监测提供了一种新的思路。 展开更多
关键词 CsPbBr_(3) 钙钛矿 核壳结构 异质结 H_(2)s气体传感器 氧吸附原理
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