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The Bipolar Field-Effect Transistor:Ⅳ.Short Channel Drift-Diffusion Current Theory(Two-MOS-Gates on Pure-Base)
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作者 揭斌斌 薩支唐 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第2期193-200,共8页
This paper gives the short channel analytical theory of the bipolar field-effect transistor (BiFET) with the drift and diffusion currents separately computed in the analytical theory. As in the last-month paper whic... This paper gives the short channel analytical theory of the bipolar field-effect transistor (BiFET) with the drift and diffusion currents separately computed in the analytical theory. As in the last-month paper which represented the drift and diffusion current by the single electrochemical (potential-gradient) current, the two-dimensional transistor is partitioned into two sections, the source and drain sections, each can operate as the electron or hole emitter or collector under specific combinations of applied terminal voltages. Analytical solution is then obtained in the source and drain sections by separating the two-dimensional trap-free Shockley Equations into two one-dimensional equations parametrically coupled via the surface-electric-potential and by using electron current continuity and hole current continuity at the boundary between the emitter and collector sections. Total and the drift and diffusion components of the electron-channel and hole-channel currents and output and transfer conductances, and the electrical lengths of the two sections are computed and presented in graphs as a function of the D. C. terminal voltages for the model transistor with two identical and connected metal-oxide-silicon-gates (MOS-gates) on a thin pure-silicon base over practical ranges of thicknesses of the silicon base and gate oxide. Deviations of the two-section short-channel theory from the one-section long-channel theory are described. 展开更多
关键词 bipolar field-effect transistor theory MOS field-effect transistor simultaneous electron and hole surface and volume channels surface potential two-section short-channel theory double-gate pure-base
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The Bipolar Field-Effect Transistor:II.Drift-Diffusion Current Theory(Two-MOS-Gates on Pure-Base)
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作者 薩支唐 揭斌斌 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第12期1849-1859,共11页
This paper describes the drift-diffusion theory of the bipolar field-effect transistor (BiFET) with two identical and connected metal-oxide-silicon-gates (MOS-gates) on a thin-pure-base. Analytical solution is obt... This paper describes the drift-diffusion theory of the bipolar field-effect transistor (BiFET) with two identical and connected metal-oxide-silicon-gates (MOS-gates) on a thin-pure-base. Analytical solution is obtained by partitioning the two-dimensional transistor into two one-dimensional problems coupled by the parametric sur- face-electric-potential. Total and component output and transfer currents and conductances versus D. C. voltages from the drift-diffusion theory, and their deviations from the electrochemical (quasi-Fermi) potential-gradient theory,are presented over practical ranges of thicknesses of the silicon base and gate oxide. A substantial contri- bution from the longitudinal gradient of the square of the transverse electric field is shown. 展开更多
关键词 bipolar field-effect transistor theory MOS field-effect transistor simultaneous electron and holesurface and volume channels surface potential~ longitudinal gradient of transverse electric field
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Comparing Three of the Leadership Theories: Leader-Member Exchange Theory,transformational Leadership and Team Leadership
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作者 王子涵 《中国校外教育(上旬)》 2013年第S2期122-124,共3页
Leadership is a complex process.It is one of the most researched areas around the world.It has gained importance in every walk of life from politics to business and from education to social organizations.According to ... Leadership is a complex process.It is one of the most researched areas around the world.It has gained importance in every walk of life from politics to business and from education to social organizations.According to the study of"Leadership in Adult Education Venues",here has a much more clear recognition of leadership:leadership is a process whereby an individual influences a group of individuals to achieve a common goal.There are many approaches of leadership throughout the study of this class,the three theories of leadership I choose to describe in this paper are:Leader-Member Exchange(LMX)Theory,Transformational Leadership,and Team Leadership. 展开更多
关键词 Leader-Member EXCHANGE theory Transformational LEA
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问题与回答——Theorizing A New Agenda for Architecture,An Anthology of Architectural Theory,1965~1995一书引起的思考
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作者 张巍 王一平 《华中建筑》 2010年第3期4-6,共3页
内斯比特(KateNesbitt)在她的Theorizing A New Agenda for Architecture,An Anthology of Architectural Theory,1965~1995一书中较为全面地介绍了当代西方建筑理论界所关心的主要问题及其相关的思考。对于这些问题,国内建筑理论界也... 内斯比特(KateNesbitt)在她的Theorizing A New Agenda for Architecture,An Anthology of Architectural Theory,1965~1995一书中较为全面地介绍了当代西方建筑理论界所关心的主要问题及其相关的思考。对于这些问题,国内建筑理论界也有自己的认识。该文通过对两者的比较,试图理清建筑理论的基本意义,那就是提出问题并引起思考。 展开更多
关键词 问题 回答 理论的意义
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SEMICLASSICAL LIMIT FOR BIPOLAR QUANTUM DRIFT-DIFFUSION MODEL 被引量:4
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作者 琚强昌 陈丽 《Acta Mathematica Scientia》 SCIE CSCD 2009年第2期285-293,共9页
Semiclassical limit to the solution of transient bipolar quantum drift-diffusion model in semiconductor simulation is discussed. It is proved that the semiclassical limit of this solution satisfies the classical bipol... Semiclassical limit to the solution of transient bipolar quantum drift-diffusion model in semiconductor simulation is discussed. It is proved that the semiclassical limit of this solution satisfies the classical bipolar drift-diffusion model. In addition, the authors also prove the existence of weak solution. 展开更多
关键词 Quantum drift-diffusion weak solution semiclassical limit BIPOLAR
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ASYMPTOTIC BEHAVIOR OF THE DRIFT-DIFFUSION SEMICONDUCTOR EQUATIONS 被引量:3
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作者 郭秀兰 李开泰 《Acta Mathematica Scientia》 SCIE CSCD 2004年第3期385-394,共10页
This paper is devoted to the long time behavior for the Drift-diffusion semiconductor equations. It is proved that the dynamical system has a compact, connected and maximal attractor when the mobilities are constants ... This paper is devoted to the long time behavior for the Drift-diffusion semiconductor equations. It is proved that the dynamical system has a compact, connected and maximal attractor when the mobilities are constants and generation-recombination term is the Auger model; as well as the semigroup S(t) denned by the solutions map is differential. Moreover the upper bound of Hausdorff dimension for the attractor is given. 展开更多
关键词 drift-diffusion model auger term ATTRACTOR Housdorff dimensions
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Weak solutions to one-dimensional quantum drift-diffusion equations for semiconductors
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作者 蒋卫祥 管平 《Journal of Southeast University(English Edition)》 EI CAS 2006年第4期577-581,共5页
The weak solutions to the stationary quantum drift-diffusion equations (QDD) for semiconductor devices are investigated in one space dimension. The proofs are based on a reformulation of the system as a fourth-order... The weak solutions to the stationary quantum drift-diffusion equations (QDD) for semiconductor devices are investigated in one space dimension. The proofs are based on a reformulation of the system as a fourth-order elliptic boundary value problem by using an exponential variable transformation. The techniques of a priori estimates and Leray-Schauder's fixed-point theorem are employed to prove the existence. Furthermore, the uniqueness of solutions and the semiclassical limit δ→0 from QDD to the classical drift-diffusion (DD) model are studied. 展开更多
关键词 semiconductor device quantum drift-diffusion equations existence and uniqueness exponential variable transformation semiclassical limit
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RENEWAL OF BASIC LAWS AND PRINCIPLES FOR POLAR CON-TINUUM THEORIES (Ⅱ)—MICROMORPHIC CONTINUUM THEORY AND COUPLE STRESS THEORY 被引量:2
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作者 戴天民 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第10期1126-1133,共8页
The purpose is to reestablish the balance laws of momentum, angular momentum and energy and to derive the corresponding local and nonlocal balance equations for micromorphic continuum mechanics and couple stress theor... The purpose is to reestablish the balance laws of momentum, angular momentum and energy and to derive the corresponding local and nonlocal balance equations for micromorphic continuum mechanics and couple stress theory. The desired results for micromorphic continuum mechanics and couple stress theory are naturally obtained via direct transitions and reductions from the coupled conservation law of energy for micropolar continuum theory, respectively. The basic balance laws and equations for micromorphic continuum mechanics and couple stress theory are constituted by combining these results derived here and the traditional conservation laws and equations of mass and microinertia and the entropy inequality. The incomplete degrees of the former related continuum theories are clarified. Finally, some special cases are conveniently derived. 展开更多
关键词 micromorphic continuum couple stress theory COUPLED basic balance law balance equation
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Nonlinear free vibration of piezoelectric semiconductor doubly-curved shells based on nonlinear drift-diffusion model 被引量:1
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作者 Changsong ZHU Xueqian FANG Jinxi LIU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第10期1761-1776,共16页
In this paper, the nonlinear free vibration behaviors of the piezoelectric semiconductor(PS) doubly-curved shell resting on the Pasternak foundation are studied within the framework of the nonlinear drift-diffusion(NL... In this paper, the nonlinear free vibration behaviors of the piezoelectric semiconductor(PS) doubly-curved shell resting on the Pasternak foundation are studied within the framework of the nonlinear drift-diffusion(NLDD) model and the first-order shear deformation theory. The nonlinear constitutive relations are presented, and the strain energy, kinetic energy, and virtual work of the PS doubly-curved shell are derived.Based on Hamilton's principle as well as the condition of charge continuity, the nonlinear governing equations are achieved, and then these equations are solved by means of an efficient iteration method. Several numerical examples are given to show the effect of the nonlinear drift current, elastic foundation parameters as well as geometric parameters on the nonlinear vibration frequency, and the damping characteristic of the PS doublycurved shell. The main innovations of the manuscript are that the difference between the linearized drift-diffusion(LDD) model and the NLDD model is revealed, and an effective method is proposed to select a proper initial electron concentration for the LDD model. 展开更多
关键词 nonlinear free vibration piezoelectric semiconductor(PS)doubly-curved shell nonlinear drift-diffusion(NLDD)model linearized drift-diffusion(LDD)model
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半导体drift-diffusion模型的局部间断Galerkin方法及数值模拟
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作者 肖红单 刘蕴贤 《山东大学学报(理学版)》 CAS CSCD 北大核心 2023年第4期1-7,共7页
考虑半导体drift-diffusion(DD)模型一维和二维问题的局部间断Galerkin(LDG)方法,并进行数值模拟。模拟一维问题时,在浓度变化剧烈的部分采用细网格,在浓度变化平缓的地方采用粗网格,并与均匀网格的数值模拟进行比较,实现了在非均匀剖... 考虑半导体drift-diffusion(DD)模型一维和二维问题的局部间断Galerkin(LDG)方法,并进行数值模拟。模拟一维问题时,在浓度变化剧烈的部分采用细网格,在浓度变化平缓的地方采用粗网格,并与均匀网格的数值模拟进行比较,实现了在非均匀剖分下节省空间剖分单元数并加快了运行速度的目的。模拟二维问题时,采用了Dirichlet和Neumann相结合的边界。数值结果验证了LDG方法的稳定性。 展开更多
关键词 半导体 drift-diffusion模型 局部间断Galerkin方法
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Existence of Global Attractor for the One-Dimensional Bipolar Quantum Drift-Diffusion Model 被引量:1
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作者 LIU Yannan SUN Wenlong LI Yeping 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2017年第4期277-282,共6页
In this paper, we investigate a one-dimensional bipolar quantum drift-diffusion model from semiconductor devices. We mainly show the long-time behavior of solutions to the one-dimensional bipolar quantum drift-diffusi... In this paper, we investigate a one-dimensional bipolar quantum drift-diffusion model from semiconductor devices. We mainly show the long-time behavior of solutions to the one-dimensional bipolar quantum drift-diffusion model in a bounded domain. That is, we prove the existence of the global attractor for the solution. 展开更多
关键词 bipolar quantum drift-diffusion model globalattractor energy estimate
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Asymptotic Behavior of Solutions of the Bipolar Quantum Drift-Diffusion Model in the Quarter Plane
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作者 LIU fang LI Yeping 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2019年第6期467-473,共7页
In this study, we consider the one-dimensional bipolar quantum drift-diffusion model, which consists of the coupled nonlinear fourth-order parabolic equation and the electric field equation. We first show the global e... In this study, we consider the one-dimensional bipolar quantum drift-diffusion model, which consists of the coupled nonlinear fourth-order parabolic equation and the electric field equation. We first show the global existence of the strong solution of the initial boundary value problem in the quarter plane. Moreover, we show the self-similarity property of the strong solution of the bipolar quantum drift-diffusion model in the large time. Namely, we show the unique global strong solution with strictly positive density to the initial boundary value problem of the quantum drift-diffusion model, which in large time, tends to have a self-similar wave at an algebraic time-decay rate. We prove them in an energy method. 展开更多
关键词 ASYMPTOTIC behavior quantum drift-diffusion model SELF-SIMILAR wave energy ESTIMATE
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On Global Boundedness of Solutions for the Drift-diffusion Semiconductor Equations
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作者 GUO Xiu-lan ZHANG Yu-lan LI Gong-sheng 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第4期590-596,共7页
This paper is devoted to the mixed initial-boundary value problem for the semiconductor equations. Using Stampacchia recurrence method, we prove that the solutions areglobally bounded and positive.
关键词 drift-diffusion model semiconductor equations global boundedness stampac-chia recurrence method
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Asymptotic Behavior of Solutions for the One-Dimensional Drift-Diffusion Model in the Quarter Plane
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作者 ZHOU Fang 《Wuhan University Journal of Natural Sciences》 CAS 2014年第2期144-148,共5页
In this paper, we study the classical drift-diffusion model arising from the semiconductor device simulation, which is the simplest macroscopic model describing the dynamics of the electron and the hole. We prove the ... In this paper, we study the classical drift-diffusion model arising from the semiconductor device simulation, which is the simplest macroscopic model describing the dynamics of the electron and the hole. We prove the global existence of strong solutions for the initial boundary value problem in the quarter plane. In particular, we show that in large time, these solutions tend to the nonlinear diffusion wave which is different from the steady state, at an algebraic time-decay rate. As far as we know, this is the first result about the nonlinear diffusion wave phenomena of the solutions for the one-dimensional drift-diffusion model in the quarter plane. 展开更多
关键词 asymptotic behavior drift-diffusion model nonli- near diffusion wave energy estimates
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BASIC EQUATIONS, THEORY AND PRINCIPLE OF COMPUTATIONAL STOCK MARKET (Ⅲ)—BASIC THEORIES
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作者 云天铨 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第8期861-868,共8页
By basic equations, two basic theories are presented: 1.Theory of stock's value v *(t)=v *(0) exp (ar * 2t); 2. Theory of conservation of stock's energy. Let stock's energy be defined as a q... By basic equations, two basic theories are presented: 1.Theory of stock's value v *(t)=v *(0) exp (ar * 2t); 2. Theory of conservation of stock's energy. Let stock's energy be defined as a quadratic function of stock's price v and its derivative , =Av 2+ Bv+C 2+Dv, under the constraint of basic equation, the problem was reduced to a problem of constrained optimization along optimal path. Using Lagrange multiplier and Euler equation of variation method, it can be proved that keeps conservation for any v,. The application of these equations and theories on judgement and analysis of tendency of stock market are given, and the judgement is checked to be correct by the recorded tendency of Shenzhen and Shanghai stock markets. 展开更多
关键词 political economics theory of value of goods variational method Euler equation conservation law
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About the Conflicts between the Unitary Quantum Theory and the Special and General Relativity Theories
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作者 Leo G. Sapogin V. A. Dzhanibekov +3 位作者 M. A. Moкulsky Yu. A. Ryabov Yu. P. Savin V. I. Utchastkin 《Journal of Modern Physics》 2015年第6期780-785,共6页
The authors discuss contradictions between the principal branches of the modern physical picture of the universe. Space and time have been shown in the Unitary Quantum Theory (UQT) not to be connected one with the oth... The authors discuss contradictions between the principal branches of the modern physical picture of the universe. Space and time have been shown in the Unitary Quantum Theory (UQT) not to be connected one with the other, unlike in the Special Theory of Relativity. In UQT, time becomes Newtonian again, and the growth of the particle’s mass with growing speed proceeds from other considerations of physics. Unlike the quantum theory, the modern gravitation theory (the general theory of relativity) is not confirmed by experiments and needs to be considerably revised. 展开更多
关键词 UNITARY Quantum theory General RELATIVITY SPECIAL RELATIVITY Maxwell Equations LORENTZ TRANSFORMATIONS
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Nursing interventions based on Snyder’s hope theory for depression following percutaneous coronary interventions:A clinical study 被引量:3
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作者 Xiao Wang Hai-Feng Song Si-Min Zhang 《World Journal of Psychiatry》 2025年第2期33-40,共8页
BACKGROUND Patients with depression following coronary heart disease often exhibit insufficient psychological resilience and self-care abilities;therefore,emphasis must be placed on nursing interventions.AIM To analyz... BACKGROUND Patients with depression following coronary heart disease often exhibit insufficient psychological resilience and self-care abilities;therefore,emphasis must be placed on nursing interventions.AIM To analyze the application value of problem-oriented education combined with nursing interventions based on the Snyder hope theory model in depressed patients after percutaneous coronary intervention(PCI).METHODS This study included 150 patients diagnosed with PCI postoperative depression because of coronary heart disease between February 2022 and February 2024.Participants were divided into two groups:A control group(n=75)receiving problem-oriented education and an observation group(n=75)receiving combined nursing interventions based on the Snyder hope theory model.Depression status,psychological resilience,self-care ability,and quality of life were compared between the two groups.RESULTS Before nursing interventions,there were no significant differences between the two groups(P>0.05).After the interventions,depression scores decreased while psychological resilience,self-care ability,and quality of life scores increased significantly in the observation group compared to that in the control group,with statistically significant differences noted(P<0.05).This combined approach can enhance psychological resilience,improve self-care abilities,and elevate the overall quality of life,warranting further promotion in clinical practice.CONCLUSION Combination of problem-oriented education and nursing interventions based on the Snyder hope theory model effectively alleviates depression in patients following PCI for coronary heart disease. 展开更多
关键词 Problem-oriented education Snyder hope theory model Coronary heart disease DEPRESSION Psychological resilience Self-care ability
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Bubble Theory and its Applications in Underwater Explosion, Marine Cavitation, and Seismic Exploration 被引量:1
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作者 Runze Xu Shiping Wang +1 位作者 Hemant J.Sagar Haikun Wang 《哈尔滨工程大学学报(英文版)》 2025年第2期255-284,共30页
Bubbles play crucial roles in various fields,including naval and ocean engineering,chemical engineering,and biochemical engineering.Numerous theoretical analyses,numerical simulations,and experimental studies have bee... Bubbles play crucial roles in various fields,including naval and ocean engineering,chemical engineering,and biochemical engineering.Numerous theoretical analyses,numerical simulations,and experimental studies have been conducted to reveal the mysteries of bubble motion and its mechanisms.These efforts have significantly advanced research in bubble dynamics,where theoretical study is an efficient method for bubble motion prediction.Since Lord Rayleigh introduced the theoretical model of single-bubble motion in incompressible fluid in 1917,theoretical studies have been pivotal in understanding bubble dynamics.This study provides a comprehensive review of the development and applicability of theoretical studies in bubble dynamics using typical theoretical bubble models across different periods as a focal point and an overview of bubble theory applications in underwater explosion,marine cavitation,and seismic exploration.This study aims to serve as a reference and catalyst for further advancements in theoretical analysis and practical applications of bubble theory across marine fields. 展开更多
关键词 Bubble theory Underwater explosion Marine cavitation Seismic exploration
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Mole-inspired Forepaw Design and Optimization Based on Resistive Force Theory 被引量:1
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作者 Tao Zhang Zhaofeng Liang +8 位作者 Hongmin Zheng Zibiao Chen Kunquan Zheng Ran Xu Jiabin Liu Haifei Zhu Yisheng Guan Kun Xu Xilun Ding 《Journal of Bionic Engineering》 2025年第1期171-180,共10页
Moles exhibit highly effective capabilities due to their unique body structures and digging techniques,making them ideal models for biomimetic research.However,a major challenge for mole-inspired robots lies in overco... Moles exhibit highly effective capabilities due to their unique body structures and digging techniques,making them ideal models for biomimetic research.However,a major challenge for mole-inspired robots lies in overcoming resistance in granular media when burrowing with forelimbs.In the absence of effective forepaw design strategies,most robotic designs rely on increased power to enhance performance.To address this issue,this paper employs Resistive Force Theory to optimize mole-inspired forepaws,aiming to enhance burrowing efficiency.By analyzing the relationship between geometric parameters and burrowing forces,we propose several forepaw design variations.Through granular resistance assessments,an effective forepaw configuration is identified and further refined using parameters such as longitudinal and transverse curvature.Subsequently,the Particle Swarm Optimization algorithm is applied to determine the optimal forepaw design.In force-loading tests,the optimized forepaw demonstrated a 79.44%reduction in granular lift force and a 22.55%increase in propulsive force compared with the control group.In robotic burrowing experiments,the optimized forepaw achieved the longest burrow displacement(179.528 mm)and the lowest burrowing lift force(0.9355 mm/s),verifying its effectiveness in reducing the lift force and enhancing the propulsive force. 展开更多
关键词 Resistive force theory Mole-inspired forepaw design Structural optimization Bioinspired robot
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Element Transfer Reaction theory:Scientific connotation and its applications in chemical industry 被引量:1
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作者 Hongen Cao Xinrui Xiao +2 位作者 Xu Zhang Yiyang Zhang Lei Yu 《Chinese Chemical Letters》 2025年第9期4-7,共4页
Element Transfer Reaction(ETR)theory is a new fundamental theory guiding the design of synthetic routes.It analyses problems from a brand-new perspective of element circulation,decomposing the factors affecting synthe... Element Transfer Reaction(ETR)theory is a new fundamental theory guiding the design of synthetic routes.It analyses problems from a brand-new perspective of element circulation,decomposing the factors affecting synthetic efficiency into three elements:element sources,driving force,and output.Different from the retrosynthetic analysis method and the atom economy theory,the ETR theory places more emphasis on examining the problem as a whole and comprehensively considering various factors involved in industrial applications.This perspective intends to elaborate on the scientific connotation of the ETR theory and explore its characteristics by discussing the practical application cases. 展开更多
关键词 Element Transfer Reaction theory Element source Driving force OUTPUT Energy conservation Atom economy
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