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“迁移法”解非质点类机械能守恒问题
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作者 陈卫国 《数理化解题研究》 2023年第16期120-121,共2页
根据“非质点类”模型物理特点,采用“迁移法”,利用机械能守恒对“非质点类”模型运动情况进行分析与计算,论证了迁移法在解决“非质点类机械能守恒”问题时的价值.
关键词 迁移法 非质点 机械能守恒
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基于非质点模型的纯方位解距离方法 被引量:1
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作者 石杰 戚国庆 盛安冬 《计算机与数字工程》 2013年第7期1070-1073,共4页
目标距离是战场进行作战决策和武器使用时考虑的一个重要参数。在传统的二维被动跟踪系统基础上,将目标建模为椭圆刚体。论文借鉴修正极坐标(MPC)的思想,利用刚体目标的尺寸参数,建立目标的状态模型和测量模型。采用无迹卡尔曼滤波(UKF... 目标距离是战场进行作战决策和武器使用时考虑的一个重要参数。在传统的二维被动跟踪系统基础上,将目标建模为椭圆刚体。论文借鉴修正极坐标(MPC)的思想,利用刚体目标的尺寸参数,建立目标的状态模型和测量模型。采用无迹卡尔曼滤波(UKF)算法进行解距离,为工程实现提供了可能性,并从不同的初始条件下分析了距离误差。Monte-Carlo仿真表明:在新的状态模型下利用UKF算法进行解距离,可以达到较高的精度。其中传感器与目标的相对速度和刚体目标的尺寸对距离解的精度影响较大。 展开更多
关键词 非质点 纯方位 线性滤波器 解距离
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列车附加阻力的非质点计算方法探讨
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作者 萨殊利 丁培华 贾慧娟 《北方交通大学学报》 CSCD 北大核心 1995年第2期246-248,共3页
列车附加阻力的非质点计算方法探讨萨殊利,丁培华,贾慧娟(北方交通大学机械工程系,北京100044)(呼和浩特铁路局)随着科学技术的发展,计算机的广泛应用,牵引计算已由手工计算方式发展到计算机计算方式。蒸汽机车已基本过... 列车附加阻力的非质点计算方法探讨萨殊利,丁培华,贾慧娟(北方交通大学机械工程系,北京100044)(呼和浩特铁路局)随着科学技术的发展,计算机的广泛应用,牵引计算已由手工计算方式发展到计算机计算方式。蒸汽机车已基本过渡为内燃、电力牵引.列车的载重和长... 展开更多
关键词 列车 附加阻力 非质点计算 阻力 牵引计算
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单摆的摆角与非质点近似
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作者 王昌军 侯威 《数理医药学杂志》 2003年第6期566-567,共2页
讨论了单摆作为简谐振动的模型 ,对其适用条件的探讨即对摆角的精度要求及单摆作为一个数学摆的近似修正。
关键词 简谐振动 单摆 非质点近似 摆角 修正
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“迁移法”解非质点类机械能守恒问题
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作者 陈卫国 《物理教师》 北大核心 2023年第6期96-96,F0003,共2页
根据“非质点类”模型物理特点,采用“迁移法”,利用机械能守恒对“非质点类”模型运动情况进行分析与计算,论证了迁移法在解决“非质点类机械能守恒”问题时的价值.
关键词 迁移法 非质点 机械能守恒
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以IYPT赛题圆柱体骰子为例探讨非质点物体碰撞问题
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作者 郭逸兮 杨艺 +1 位作者 尹硕 范婷 《物理教师》 北大核心 2023年第2期93-96,F0003,共5页
碰撞是生活中常见现象,而传统教学中的碰撞理论过于简化,对包含摩擦力的非质点物体碰撞的描述与现实情况差距较大.文章以IYPT赛题圆柱体骰子为例,从冲量角度出发,考虑了摩擦力的影响,对非质点物体的碰撞理论进行分析,采用程序计算和实... 碰撞是生活中常见现象,而传统教学中的碰撞理论过于简化,对包含摩擦力的非质点物体碰撞的描述与现实情况差距较大.文章以IYPT赛题圆柱体骰子为例,从冲量角度出发,考虑了摩擦力的影响,对非质点物体的碰撞理论进行分析,采用程序计算和实验方法进行了验证.此理论分析方法有效避免了在该类问题中由错误应用碰撞系数造成的能量反常增加,为该类问题的解决提供了具有参考意义的范例. 展开更多
关键词 碰撞 非质点 摩擦 圆柱体骰子
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用Dirac符号表述的非自由质点系动力学方程 被引量:2
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作者 卢新平 《力学与实践》 CSCD 北大核心 2005年第1期76-78,共3页
研究Dirac符号在经典力学中的应用,给出一种用Dirac符号表述的非自由质点系统动力学方程,并举例说明该方程的广泛应用.
关键词 自由质点 经典力学 动力学方程 表述 系统动力学 举例 符号 应用
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解非自由质点系碰撞问题的广义动静法
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作者 张毅 《苏州城建环保学院学报》 1993年第4期17-21,共5页
本文给出了解决非自由质点系碰撞问题的广义动静法,并举例说明其应用。
关键词 自由质点 碰撞 广义动静法 动力学
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大豆种子颗粒物理性质对其运动的影响研究 被引量:3
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作者 孙素杰 尹福兰 +3 位作者 张基因 阳雄伟 曹中华 吴晓强 《农机化研究》 北大核心 2015年第5期49-53,共5页
介绍了一种对种子运动的分析方案,在对该方案进行系统的阐述及其合理性的分析的基础上,找出其中存在的不足,运用数学手段和物理方法做进一步分析。同时,考虑多方面的因素,以大豆种子为研究对象,对其做一系列理论分析,得出大豆种子运动... 介绍了一种对种子运动的分析方案,在对该方案进行系统的阐述及其合理性的分析的基础上,找出其中存在的不足,运用数学手段和物理方法做进一步分析。同时,考虑多方面的因素,以大豆种子为研究对象,对其做一系列理论分析,得出大豆种子运动速度的表达式并提出影响其运动的各内在因素和外在因素,以说明实例中分析方案的不足之处,并对起决定作用的内在因素进行了分析。之后,从大豆种子自身的影响因素出发进行了一系列实验和统计分析,说明了种子的物理性质对其运动产生显著影响,即质点化研究对于种子来说是不可取的。最终,提出种子颗粒自身物理性质对其运动的影响方式和影响力度,从而为相关的机械设计提供理论参考。 展开更多
关键词 种子 非质点 物理性质 回归分析
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Clifford几何与量子力学的基本原理
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作者 于学刚 《通化师范学院学报》 1998年第5期1-6,共6页
本文运用Clfford空间的方向奇异性,对微观粒子的波粒二象性、光量子假设、能级理论以及不确定原理赋于一种几何解释。
关键词 Clifford几何 定向格式化 非质点相格 时间量子化 全域相关性
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The application study on the multi-scales integrated prediction method to fractured reservoir description 被引量:17
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作者 陈双全 曾联波 +3 位作者 黄平 孙绍寒 张琬璐 李向阳 《Applied Geophysics》 SCIE CSCD 2016年第1期80-92,219,共14页
In this paper,we implement three scales of fracture integrated prediction study by classifying it to macro-( 1/4/λ),meso-( 1/100λ and 1/4λ) and micro-( 1/100λ) scales.Based on the multi-scales rock physics ... In this paper,we implement three scales of fracture integrated prediction study by classifying it to macro-( 1/4/λ),meso-( 1/100λ and 1/4λ) and micro-( 1/100λ) scales.Based on the multi-scales rock physics modelling technique,the seismic azimuthal anisotropy characteristic is analyzed for distinguishing the fractures of meso-scale.Furthermore,by integrating geological core fracture description,image well-logging fracture interpretation,seismic attributes macro-scale fracture prediction and core slice micro-scale fracture characterization,an comprehensive multi-scale fracture prediction methodology and technique workflow are proposed by using geology,well-logging and seismic multi-attributes.Firstly,utilizing the geology core slice observation(Fractures description) and image well-logging data interpretation results,the main governing factors of fracture development are obtained,and then the control factors of the development of regional macro-scale fractures are carried out via modelling of the tectonic stress field.For the meso-scale fracture description,the poststack geometric attributes are used to describe the macro-scale fracture as well,the prestack attenuation seismic attribute is used to predict the meso-scale fracture.Finally,by combining lithological statistic inversion with superposed results of faults,the relationship of the meso-scale fractures,lithology and faults can be reasonably interpreted and the cause of meso-scale fractures can be verified.The micro-scale fracture description is mainly implemented by using the electron microscope scanning of cores.Therefore,the development of fractures in reservoirs is assessed by valuating three classes of fracture prediction results.An integrated fracture prediction application to a real field in Sichuan basin,where limestone reservoir fractures developed,is implemented.The application results in the study area indicates that the proposed multi-scales integrated fracture prediction method and the technique procedureare able to deal with the strong heterogeneity and multi-scales problems in fracture prediction.Moreover,the multi-scale fracture prediction technique integrated with geology,well-logging and seismic multi-information can help improve the reservoir characterization and sweet-spots prediction for the fractured hydrocarbon reservoirs. 展开更多
关键词 Multi-scales Fracture prediction HETEROGENEITY Reservoir characterization Sweet-spots prediction
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微元法在高中物理教学中的运用及其教学策略 被引量:5
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作者 杨习志 《物理教学探讨(中学教学教研版)》 2018年第12期52-54,57,共4页
本文首先指出学生对于运用微元法解题的困难在于不知道所遇到的问题要用微元法解决,而中学老师对于微元法的常规教学大多以遇题讲题的方式为主,并没有教会学生去发现什么情况下该用微元法解题。故笔者经过研究和思考后指出,当研究对象... 本文首先指出学生对于运用微元法解题的困难在于不知道所遇到的问题要用微元法解决,而中学老师对于微元法的常规教学大多以遇题讲题的方式为主,并没有教会学生去发现什么情况下该用微元法解题。故笔者经过研究和思考后指出,当研究对象不是质点但连续可变或研究过程所涉及的核心物理量在连续变化,而这个变化使得我们无法用中学阶段的常规公式或规律求解时,可考虑用微元法。 展开更多
关键词 微元法 连续可变 非质点问题 教学策略
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动静法札记 被引量:1
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作者 冯立富 郭书祥 《力学与实践》 CSCD 北大核心 2003年第1期70-71,共2页
通过实例阐明求解一般的动力学问题时,应用动静法较为麻烦.指出动静法产生和发展于对静力学较为了解,但对动力学了解甚少的时代,而在对动力学较为了解的今天,则不宜再过分强调动静法的作用.
关键词 动力学 静力学 动静法 动量矩定理 质心运动定理 自由质点
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拉格朗日方程与牛顿方程之比较
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作者 张玲 《甘肃高师学报》 2003年第5期35-35,共1页
说明了拉氏方程与牛顿方程的 :“等价性”
关键词 拉格朗日方程 牛顿方程 广义坐标 广义速度 自由质点 动力学
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Melting heat transfer with radiative effects and homogeneous–heterogeneous reaction in thermally stratified stagnation flow embedded in porous medium 被引量:4
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作者 M.JAVED M.FAROOQ +1 位作者 S.AHMAD Aisha ANJUM 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第11期2701-2711,共11页
The present article deals with thermally stratified stagnation-point flow saturated in porous medium on surface of variable thickness along with more convincing and reliable surface condition termed as melting heat tr... The present article deals with thermally stratified stagnation-point flow saturated in porous medium on surface of variable thickness along with more convincing and reliable surface condition termed as melting heat transfer.Homogeneous–heterogeneous reaction and radiative effects have been further taken into account to reconnoiterproperties of heat transfer.Melting heat transfer and phenomenon of homogeneous–heterogeneous reaction have engrossed widespread utilization in purification of metals,welding process,electroslag melting,biochemical systems,catalysis and several industrial developments.Suitable transformations are utilized to attain a scheme of ordinary differential equations possessing exceedingly nonlinear nature.Homotopic process is employed to develop convergent solutions of the resulting problem.Discussion regarding velocity,thermal field and concentration distribution for several involved parameters is pivotal part.Graphical behaviors of skin friction coefficient and Nusselt number are also portrayed.Concentration of the reactants is found to depreciate as a result of strength of both heterogeneous and homogeneous reaction parameters.With existence of melting phenomenon,declining attitude of fluid temperature is observed for higher radiation parameter. 展开更多
关键词 melting heat transfer porous medium stagnation point variable sheet thickness homogeneous– heterogeneous reaction
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Assessment of Point and Nonpoint Sources Pollution in Songhua River Basin,Northeast China by Using Revised Water Quality Model 被引量:14
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作者 YANG Yuhong YAN Baixing SHEN Wanbin 《Chinese Geographical Science》 SCIE CSCD 2010年第1期30-36,共7页
Individual participation of pollutants in the pollution load should be estimated even if roughly for the appropriate environmental management of a river basin.It is difficult to identify the sources and to quantify th... Individual participation of pollutants in the pollution load should be estimated even if roughly for the appropriate environmental management of a river basin.It is difficult to identify the sources and to quantify the load, especially in modeling nonpoint source.In this study a revised model was established by integrating point and nonpoint sources into one-dimensional Streeter-Phelps(S-P) model on the basis of real-time hydrologic data and surface water quality monitoring data in the Jilin Reach of the Songhua River Basin.Chemical oxygen demand(COD) and ammonia nitrogen(NH 3-N) loads were estimated.Results showed that COD loads of point source and nonpoint source were 134 958 t/yr and 86 209 t/yr, accounting for 61.02% and 38.98% of total loads, respectively.NH 3-N loads of point source and nonpoint source were 16 739 t/yr and 14 272 t/yr, accounting for 53.98% and 46.02%, respectively.Point source pollution was stronger than nonpoint source pollution in the study area at present.The water quality of upstream was better than that of downstream of the rivers and cities.It is indispensable to treat industrial wastewater and municipal sewage out of point sources, to adopt the best management practices to control diffuse pollutants from agricultural land and urban surface runoff in improving water quality of the Songhua River Basin.The revised S-P model can be successfully used to identify pollution source and quantify point source and nonpoint source loads by calibrating and validating. 展开更多
关键词 ammonia nitrogen chemical oxygen demand nonpoint source pollution point source pollution revised water quality model Songhua River Basin
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Linear and Nonlinear Optical Properties in Spherical Quantum Dots 被引量:1
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作者 Yusuf Yakar Bekir Cakir Ayhan Ozmen 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第6期1185-1189,共5页
We calculate the energy eigenvalues and the sate functions of one-electron Quantum Dot (QD) by using a combination of Quantum Genetic Algorithm (QGA) and Hartre-Fock-Roothaan (HFR) method. The linear and the thi... We calculate the energy eigenvalues and the sate functions of one-electron Quantum Dot (QD) by using a combination of Quantum Genetic Algorithm (QGA) and Hartre-Fock-Roothaan (HFR) method. The linear and the third-order nonlinear optical absorption coefficients for the 1s-1p, 1p-1d, and 1d-1f transitions are examined as a function of the incident photon energy for three different values of the stoichiometric ratio. The results show that the stoichiometric ratio, impurity, relaxation time, and dot size have great influence on the optical absorption coefficients of QDs. 展开更多
关键词 optical properties spherical quantum dot QGA and HFR method
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Linear and Nonlinear Optical Absorptions of a Donor Impurity in Spherical Quantum Dots 被引量:1
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作者 XIE Wen-Fang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第7期155-158,共4页
An investigation of the optical properties of a hydrogenic donor in spherical parabolic quantum dots hasbeen performed by using the matrix diagonalization method.The optical absorption coefficient between the ground(L... An investigation of the optical properties of a hydrogenic donor in spherical parabolic quantum dots hasbeen performed by using the matrix diagonalization method.The optical absorption coefficient between the ground(L=0) and the first excited state (L=1) have been examined based on the computed energies and wave functions.The results are presented as a function of the incident photon energy for the different values of the confinement strength.These results show the effects of the quantum size and the impurity on the optical absorption coefficient of a donorimpurity quantum dot. 展开更多
关键词 quantum dot optical absorption
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Linear and Nonlinear Optical Properties of Spherical Quantum Dots:Effects of Hydrogenic Impurity and Conduction Band Non-Parabolicity 被引量:4
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作者 G.Rezaei B.Vaseghi N.A.Doostimotlagh 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第3期485-489,共5页
Simultaneous effects of an on-center hydrogenic impurity and band edge non-parabolicity on intersubband optical absorption coefficients and refractive index changes of a typical GaAs/AlxGa1-xAs spherical quantum dot a... Simultaneous effects of an on-center hydrogenic impurity and band edge non-parabolicity on intersubband optical absorption coefficients and refractive index changes of a typical GaAs/AlxGa1-xAs spherical quantum dot are theoretically investigated, using the Luttinger-Kohn effective mass equation. So, electronic structure and optical properties of the system are studied by means of the matrix diagonalization technique and compact density matrix approach, respectively. Finally, effects of an impurity, band edge non-parabolicity, incident light intensity and the dot size on the linear, the third-order nonlinear and the total optical absorption coemcients and refractive index changes are investigated. Our results indicate that, the magnitudes of these optical quantities increase and their peaks shift to higher energies as the influences of the impurity and the band edge non-parabolicity are considered. Moreover, incident light intensity and the dot size have considerable effects on the optical absorption coefficients and refractive index changes. 展开更多
关键词 hydrogenic impurity non-parabolic conduction band quantum dots absorption coefficient refractive index
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