液体粘性对离心式喷嘴喷雾浓度分布和喷雾锥角影响的理论与试验研究

本文从理论和试验上研究了液体粘性对离心式喷嘴喷雾浓度分布,喷雾锥角和雾化粒度的影响,建立了喷嘴后方液体浓度分布的物理数学模型.首次考虑了喷嘴出口空气涡的影响,给出了浓度分布、喷雾锥角和索太尔平均直径的计算方法.运用激光散射测雾技术,对喷嘴在静止空气中的雾化特性进行了研究,给出了喷雾锥角和索太尔平均直径的经验公式,并从试验上验证了所建立的数学模型.     

结合民航行业实际 优化我院《运筹学》教学效果

针对我院课时限制和文理专业学生数学素养不一,只能选讲运筹学的某些简单易懂的分支,在有限的课时内重点介绍运筹学的思想方法,培养学生解决实际问题的能力,谈谈自己的教学体会和建议。     

高校创业教育系统的构建——基于协同学视角

协同创新作为一种全新的教育理念,为高校教育教学改革,尤其是创业教育指明了方向。基于协同学理论和大学生创业教育体系相互关系,分析了高校创业教育中存在的突出问题,从理念、内容、组织和政策四个层面构建了创业教育的系统模型。     

落实科学发展观 全面推进陕西县域经济发展

县域经济作为国民经济的基础性单元,充满着活力,蕴涵着希望,在建设全面小康社会和社会主义新农村的进程中越来越受到社会各界的关注。通过对陕西省县域经济发展的总体现状阐述,以神木县为典型代表进行实证分析,提出陕西省县域经济发展加快几点建议。     

干线机襟翼运动模拟的研究

随着ＣＡＤ／ＣＡＭ 研究的不断深入与发展，产品数字化定义、数字化预装配、运动机构动态模拟／ 仿真等技术逐渐受到广泛重视和应用。本文介绍了干线机襟翼运动模拟的研究应用，对襟翼理论模型的建立、运动机构的定义、运动模拟、干涉检查等过程及一些技术难点作了论述，并对研究的意义进行了说明。     

双翼金属圆柱体散射场的整体计算

本文利用keller的几何绕射理论（GTD）推求出双翼金属圆柱体散射场高频快收敛整体解，弥补了传统分离解（把系统分解为一个金属圆柱和两个金属半平面，分别求解再简单迭加）的不足之处，最后，给出了整体解和分离解的散射电场的模值数值计算结果。     

Motion equations of hemispherical resonator and analysis of frequency split caused by slight mass non-uniformity

The mass non-uniformity of hemispherical resonator is one of reasons for frequency split, and frequency split can cause gyroscope to drift. Therefore, it is of great significance to analyze the relationship between mass non-uniformity and frequency split, which can provide a theoretical basis for mass balance of imperfect resonator. The starting point of error mechanism analysis for gyroscope is the motion equations of resonator. Firstly, based on the Kirchhoff-Love hypothesis in the elastic thin shell theory, the geometric deformation equations of resonator are deduced. Secondly, the deformation energy equation of resonator is derived according to the vibration mode and relationship between the stress and strain of hemispherical thin shell. Thirdly, the kinetic energy equation of resonator is deduced by the Coriolis theorem. Finally, the motion equations of resonator are established by the Lagrange mechanics principle. The theoretical values of precession factor and natural frequency are calculated by the motion equations, which are substantially consistent with the ones by the finite element method and practical measurement, the errors are within a reasonable range. Simultaneously, the varying trend of natural frequency with respect to the geometrical and physical parameters of resonator by the motion equations is consistent with that by the finite element analysis. The above conclusions prove the correctness and rationality of motion equations. Similarly, the motion equations of resonator with mass non-uniformity are established by the same modeling method in case of ignoring the input angular rate and damping, and the state equations with respect to the velocity and displacement of vibration system are derived, then two natural frequencies are solved by the characteristic equation. It is concluded that one of reasons for frequency split is the 4th harmonic of mass non-uniformity, and thus much attention should be paid to minimizing the 4th harmonic of mass non-uniformity in the course of mass balancing for imperfect resonator.     

GEO移动通信卫星合成多波束天线仿真分析

针对地球静止轨道（GEO）移动通信卫星星上多波束天线波束成形技术,研究了合成多波束对地覆盖、点波束天线增益以及波束间干扰抑制技术。利用仿真分析软件进行多波束天线的波束成形仿真分析,优化了天线系统的设计参数,改善了波束间的隔离度指标,提高了系统通信性能和局部地区的信道容量,完成了地球静止轨道移动通信卫星系统合成多波束天线的设计。     

An optimization model of parameter matching for aircraft catapult launch

To efficiently and fully utilize aircraft carrier resources, an optimization model is presented to deal with parameter matching between aircraft and carrier in the process of aircraft catapult launch. Based on carrier aircraft longitudinal dynamic equations and theorem of kinetic energy in catapult launch course, the work characteristics of different forces are learned and a theory model of parameter matching is deduced. In view of the uncertainty of the model parameters of the theory model and the low matching accuracy of the approximate model, an optimization model of parameter matching is introduced in line with the structure of theory model and the approximate model and is generated by the proposed immune genetic algorithm. Compared with the original genetic algorithm and immune algorithm, the proposed algorithm has better calculation accuracy and convergence. The calculation results show that the optimization model occupies certain application value of engineering estimation from the comparison with the relevant literature data and has higher precision than the approximate models. The validity of the proposed approach is verified with numerical case study on a carrier based aircraft.     

浅析英语阅读教学中的策略训练和培养

针对英语阅读教学实践中存在的问题,分析影响英语阅读效果的因素及相应对策,探讨在英语阅读教学中进行学习策略培养的途径,旨在实现从重视知识传授转移到重视培养学生获取信息的技能,强调学习策略的重要性,为推动阅读教学改革提供积极的思考和探索。