常压危险品运输罐车安全管理

常压危险货物罐车在道路运输过程中,具有较大的危险性,发生事故会导致承载危险品泄漏,对社会产生较大危害,同时造成环境污染。加强对常压危险品运输罐车的管理,应了解危险品运输罐车常见缺陷及其形成机理,加大管理力度,提高检验质量,降低危险品运输过程中的安全隐患。本文对事故发生的类型进行归纳,对事故的成因进行专业理论分析,从而提升危险品运输罐车安全性能,减少安全隐患。

变加速动力学系统的广义高斯最小拘束原理

变加速运动在日常生活和工程问题中普遍存在.变加速动力学又称牛顿猝变动力学,因其在混沌理论和非线性动力学中的应用而获得广泛关注.高斯原理是一个具有极值性质的微分变分原理.因此,研究变加速动力学系统的广义高斯原理在理论和应用两方面都有重要意义.文章提出并研究变加速动力学系统的广义高斯原理.首先,引入急动度空间的广义高斯变分概念,将质点的达朗贝尔原理对时间求导数后与广义高斯变分点乘,并利用高斯意义下的理想约束条件,建立了变加速动力学系统的广义高斯原理.在此基础上,通过构造广义拘束函数建立并证明变加速动力学系统的广义高斯最小拘束原理,并给出原理的阿佩尔形式、拉格朗日形式和尼尔森形式.其次,研究原理对变质量力学的推广.从密歇尔斯基方程出发,将它对时间求导并与广义高斯变分点乘,建立了具有理想约束的变质量变加速动力学系统的广义高斯原理.通过构造变质量系统的广义拘束函数,建立并证明变质量力学系统变加速运动的广义高斯最小拘束原理.文中以开普勒-牛顿空间问题为例,利用所得的广义高斯最小拘束原理方法进行计算,验证了方法的有效性.

信息化技术在承压类特种设备检验中的应用

【目的】为了实现对承压类特种设备的信息资源的大数据管理,构建一个数字化设备综合管理系统,建立特种设备检验管理平台。【方法】通过将信息化技术融入承压类特种设备检验管理过程中,设置检验检测人员管理、检验检测记录管理、出具检验报告、检验仪器管理等功能模块,并实现将检验检测数据上传到特种设备监督管理信息系统的功能。【结果】该系统实现了各项过程的流转、审批及查询等操作的全程可控,可记录各个承压类特种设备的检测信息,并生成检测记录、报告及检测情况告知书。【结论】该系统采用模块集成化设计,功能独立完善,能满足检验检测机构全面深入的管理需求。

时间尺度上奇异Lagrange系统对称性与守恒量

时间尺度可以统一连续分析与离散分析,Noether对称性方法又是分析力学中独特的积分方法之一,而且在实际问题中,较多1阶微分方程组可化为奇异Lagrange系统,因此对时间尺度上奇异Lagrange系统Noether对称性与守恒量的研究具有重要的理论和实际意义.首先,给出时间尺度上奇异Lagrange系统的运动微分方程;其次,讨论该系统Noether对称性和Noether准对称性的定义和判据;最后,寻求与对称性和准对称性相应的Noether守恒量,并举例说明结果的应用.

“计算方法”课程思政教学的思考与探索

"计算方法"课程是各大理工科专业的本科生和研究生数学基础课程,授课对象众多、涉及面广,具有思政教育的现实意义和授课平台;同时,该课程与实际联系紧密,可以很好地结合人、事、物进行思政教育。该文从教学目标、课程设计、教学内容、课程改革、课程考核、课程评价等方面出发,就如何挖掘思政元素,融入思政教育进行了思考,并提供了新的思路。

Perturbation Theory of Fractional Lagrangian System and Fractional Birkhoffian System

Perturbation to symmetry and adiabatic invariants are studied for the fractional Lagrangian system and the fractional Birkhoffian system in the sense of Riemann-Liouville derivatives.Firstly,the fractional Euler-Lagrange equation,the fractional Birkhoff equations as well as the fractional conservation laws for the two systems are listed.Secondly,the definition of adiabatic invariant for fractional mechanical system is given,then perturbation to symmetry and adiabatic invariants are established for the fractional Lagrangian system and the fractional Birkhoffian system under the special and general infinitesimal transformations,respectively.Finally,two examples are devoted to illustrate the results.

Discrete Fractional Lagrange Equations of Nonconservative Systems

In order to study discrete nonconservative system,Hamilton's principle within fractional difference operators of Riemann-Liouville type is given. Discrete Lagrange equations of the nonconservative system as well as the nonconservative system with dynamic constraint are established within fractional difference operators of Riemann-Liouville type from the view of time scales. Firstly,time scale calculus and fractional calculus are reviewed.Secondly,with the help of the properties of time scale calculus,discrete Lagrange equation of the nonconservative system within fractional difference operators of Riemann-Liouville type is presented. Thirdly,using the Lagrange multipliers,discrete Lagrange equation of the nonconservative system with dynamic constraint is also established.Then two special cases are discussed. Finally,two examples are devoted to illustrate the results.

变阶分数阶广义Birkhoff系统的绝热不变量

基于Caputo变阶分数阶导数研究广义Birkhoff系统对称性的摄动与绝热不变量。作为特例,同时也讨论了变阶分数阶Birkhoff系统、分数阶广义Birkhoff系统及整数阶广义Birkhoff系统的绝热不变量。最后,举例说明结果的应用。

A2O-MBR工艺对多来源难降解有机废水的深度处理

介绍了A2O-MBR工艺在多来源、难降解有机废水处理实际工程应用情况、运行效果,并对生化池中优势菌种进行了镜检和筛选分析。结果表明,生化系统中富集了大量的有效微生物,在多变、多来源、高盐度、高COD浓度条件下具有了一种特别的适应性,能够耐受复杂废水条件冲击,处理效果稳定,对降解有机物和氨氮、整体达标排放方面发挥了重要的作用。

Adiabatic Invariant for Dynamic Systems on Time Scale

Perturbation to Noether symmetry and adiabatic invariants for Birkhoffian system,Hamiltonian system and Lagrangian system with delta derivative are investigated,respectively.Firstly,the definition and some related properties of time scale calculus are listed simply as preliminaries.Secondly,the Birkhoffian system with delta derivative is studied.Based on the differential equation of motion as well as Noether symmetry and conserved quantity,perturbation to Noether symmetry and adiabatic invariant are investigated.Thirdly,adiabatic invariants for the Hamiltonian system and the Lagrangian system are presented through some transformations.And finally,an example is given to illustrate the methods and results.

Perturbation to Symmetries and Adiabatic Invariants for Generalized Birkhoffian Systems on Time Scales

Time scale is a new and powerful tool for dealing with complex dynamics problems. The main result of this study is the exact invariants and adiabatic invariants of the generalized Birkhoffian system and the constrained Birkhoffian system on time scales. Firstly, we establish the differential equations of motion for the above two systems and give the corresponding Noether symmetries and exact invariants. Then, the perturbation to the Noether symmetries and the adiabatic invariants for the systems mentioned above under the action of slight disturbance are investigated, respectively. Finally, two examples are provided to show the practicality of the findings.

Noether Theorem for Fractional Singular Systems

Noether theorems for two fractional singular systems are discussed.One system involves mixed integer and Caputo fractional derivatives,and the other involves only Caputo fractional derivatives.Firstly,the fractional primary constraints and the fractional constrained Hamilton equations are given.Then,the fractional Noether theorems of the two fractional singular systems are established,including the fractional Noether identities,the fractional Noether quasi-identities and the fractional conserved quantities.Finally,the results obtained are illustrated by two examples.

Nonshifted Adiabatic Invariant on Time Scale

Three aspects which include differential equation of motion, Noether symmetry and conserved quantity, perturbation to Noether symmetry and adiabatic invariant are investigated for the nonshifted Birkhoffian system, nonshifted Hamiltonian system and nonshifted Lagrangian system, respectively. Then, some relationships among the three mechanic systems and some special cases of the main results are presented. Finally, an example is given to illustrate the application of the methods and results.

Conserved Quantity for Fractional Constrained Hamiltonian System

Singular system has great relationship with gauge field theory,condensed matter theory and some other research areas.Based on the mixed integer and Riemann-Liouville fractional derivatives,the fractional singular system is studied.Firstly,the fractional constrained Hamilton equation and the fractional inherent constraint are presented.Secondly,Lie symmetry and conserved quantity are analyzed,including determined equation,limited equation,additional limited equation and structural equation.And finally,an example is given to illustrate the methods and results.