Dynaical Mathematical Model of String

In the process of oil drilling, drilling string and rock bit are main drilling tools. The fact of their failure would cause serious accidents. To solve this problem, the vibration law of string should be found. The longitudinal vibration model, torsional model and lateral vibration model are founded simultaneity. Many methods are used to build up this model, including finite element technique, numerical technique and computer simulation. The dynamic model reveals the dynamic action of string, it is instructive to design new rock bit and study drilling mechanics.     

棉花群体干物质生产与分配的数学模型研究

在１９９１～１９９３年棉花高产优质与生态环境因子关系研究的基础上，利用作物生长模拟分析的方法和大量试验资料及相关的气象资料，建立了棉花群体干物质生产与分配的数学模型。该模型包括：叶面积动态，光合生产，干物质积累和分配子模型。所建模型经检验，具有较好的模拟性能，可用于指导棉花生产。     

A Dynamic Mathematical Model of Ball Pulverized Storage System and Its Simulation with MMS

This paper presents a mathematical model , simulating program and results ofball pulverlzed coal storage system. The program of simulation is writen with ACSL language. theGear arithmetics to solve the differentlal equations is recom merded by MMS. The model has beenmodularized according to the reguirements of MMS. This modular called DTM modular can be con-sidered as one component of MMS modular library.     

Mathematical Model of Control Cooling for Screw Rod After Rolling

The on line hot treatment can not only boost the strength but also gain lower cost. It is usually called tempcore which was developed greatly these years. The process of tempcor art is introduced and the core subject mathematical models is studied. According to the heating exchanging property of screw rod in cooling after rolling.Two mathematical models including beginning cooling model and cooling water amount model are obtained by analysing, deducing theoretically and simplifying mathematically. Its structure is simple and practiced .The parameter of model is obtained from measuring data of work site. It is able to suite the change of work site, so it can be used in practiced controlling.     

预测木薯茎叶生物量的数学模型

为了构建预测木薯茎叶生物量的数学模型,调查了5个木薯品种茎秆的基部、中部、上部茎粗及茎秆长度和各个分枝的基部粗度、长度等形态学指标,并将生物量分为茎秆和分枝两部分,分别探讨这两部分生物量与相关形态指标的关系。通过多种模型的反复拟合比较,结果以主茎复合幂函数与分枝集合函数的统合方程的拟合效果较好,均方根误差RMSE为104.2,相关系数r为0.9110,拟合优度较高。并且本模型的拟合效果明显优于前人提出的预测木薯茎叶生物量的数学模型。     

Establishing and Application of the Mathematical Model of the Impulse Electroflotation Reacting Tank

The properties of the Impulse electroflotation equipment are introduced briefly ,and the factors that influence the treatment effect of Impulse electroflotation are analyzed. The mathematical model of the Impulse electroflotation reacting tank which determines the height, volume and treatment capability of Impulse electroflotation is provided on the base of the basic equations of electroflotation. A calculate software for the design of Impulse electroflotation reacting tank is developed and the source code is given.     

Mathematical Model of Flow Process in 40t/h Pyroflow Circulating Fluidized Bed Boiler

A mathematical model is presented to describe the fluiddynamics processes for the combustion system of 410t/h Pyroflow CFB boiler.A core annulus structure with solid dispersion from core to annulus is considered,and the influence of coal particles fragmentation,attrition and broad size distribution of feeding coal and bed inventory on hydrodynamics is specially taken into account.The simulation results show that the CFB boiler has good hydrodnamic characteristics and high hot cyclone efficiency.     

MATLAB和VB在温室环境模型构建中的混合编程研究

旨在找到一种MATLAB和VB混合编程的方法,实现日光温室热环境模拟模型软件的可视化编写。采用基于组件对象模型COM（component object module）的方法,研究了MATLAB和VB在模型构建中的混合编程。采用MATLAB软件编写M.源函数文件,实现理论模型中的工程计算和图像图形处理功能,M.源函数文件编译成功后,通过COM方法转换为可被独立调用的组件;采用VB软件编写主程序文件,实现良好的人机交互功能。在主程序中完成模型各项参数的赋值后,再调用COM组件进行理论模型的计算与绘图。COM组件方法可以实现MATLAB和VB的混合编程。以此构建的日光温室热环境模拟模型软件,可在主程序输入各项参数：室外气象条件,温室结构、热性能等,模拟室内热环境的变化。     

Mathematical Model of Bile Flow in a Contracting Callbladder

On the basis of the features of contracting gallbladder and properties of gallbladder bile,the mathematical model of bile flow in a living contracting gallbladder is proposed,the velocity distribution and pressure distribution are calculated by SIMPLER method.The results show that there exist obvious S vorteices near the exit, which probably form the important conditions of cholecystolithiasis.     

土壤湿度对几种除草剂药效的影响及其数学模型探讨

运用二次正交施转组合设计,以对稗草抑制率为目标函数,以除草剂用量、土壤湿度为决策变量,建立目标性状与除草剂用量及土壤湿度之间的数学模型。通过模拟寻优,得到在不同土壤湿度影响下丁草胺、乙草胺、农得时、甲磺隆４种除草剂掏抑制稗草的优化方案。模型解析结果表明,当其他条件一致时,除草剂的用量是除草效果的关键,土壤湿度对除草剂的药效存在不同程度的影响,通过调节土壤湿度可使土壤处理降草剂药效提高。     

Macroscopic and Microscopic Coupling Mathematical Model for Solidification Process of Twin-roll Thin Strip

A macroscopic and microscopic coupling mathematical model for solidification process of twin-roll thin strip is developed. In the model, the latent heat is treated by the enthalpy method, and the grid and node are divided by assumed streamline boundary. The heterogeneous nucleation and the columnar-equiaxed transform(CET)model are introduced, together with the revison of the dendrite growth dynamic model of KGT. With the help of solid fraction, the coupling of the macro/micro aspects is realized by using different grid-sizes and time-steps, macro and micro, together with the columnar dendrite front tracing. The columnar dendrite arm spacing and deflection angle calculated by proposed model are in agreement with the experimental ones. Therefore, the model is proved to be reliable, and it can be used to predict the effects of the processing parameters on the solidification structure of twin-roll thin strips.     

Mathematical Model of Oxygen Blast Furnace with Preheating Gas Injection into Upper Shaft

An One-dimensional mathematical model,based on oxygen blast furnace with preheating gas injection into upper shaft,has been developed to describe the variation of innerdiameter of blast furnace,13 chemical reactions,the heat losses through the furnace wall,the heatexchange and pressure losses between gas phase and solid phase.The characters of oxygen blastfurnace are discussed,The simulated results indicate that the tem perature of burden in creasesthroughout the upper shaft with the incrcasement of the flow and the temperature of preheating gasinjected,and that the effect of the heating-up of burden is not so large when the com positions ofpreheatin8 gas injeetion are changed.The model is contributed to obtain a deeper understanding ofthe oxygen blast furnace process.     

南疆沙壤土地面灌溉高产棉田施肥灌水数学模型研究

在南疆沙壤土棉田,设置了3个处理因子(施氮、施磷和灌水),每个因子依施用量设4个水平,开展了水肥耦合效应对棉花产量影响的田闻试验研究.试验结果表明,棉花产量对氮肥、磷肥、水的依赖程度顺序是:氮肥＞磷肥＞水,并建立了地面灌溉条件下高产棉田水肥施用的多元回归数学施肥模型:y=-677.8075+0.5889 xN+11.1...     

Numerical Simulation in Flow Field of CNG Vehicle Catalytic Converters

The steady flow in the catalytic converters of CNG was simulated. The gas can breakaway in the entering pipe and the flow of the gas can convergence well in the exhaust pipe. The flow distributing mainly depends on the flow capability of the expanding pipe. The pressure falls apparently in the carrier of catalytic converters. The noble metals in the center of the catalytic converters are consumed more quickly than the edge zone.     

玉米大豆间作种植密度耦合数学模型及其优化方案研究

云南省大豆的种植主要以与玉米间作为主,适宜的种植密度是获得高产的前提,为研究种植密度对群体产量和经济产值的影响,找到最佳种植密度组合。采用二次饱和D-最优设计,分别在云南嵩明县（A）、会泽县（B）和鲁甸县（C）等3个点进行试验。研究了玉米和大豆种植密度对群体产量和经济产值的影响,并分别建立二元二次数学模型。结果表明：玉米和大豆密度对间作群体产量和经济产值影响显著,均呈凸抛物线型变化,在低密度水平下,群体产量和经济产值随密度的增加而增加。通过模型解析表明,玉米+大豆密度组合分别为64 110株/hm ²+147 013株/hm ²（A）、63 068株/hm ²+147 116株/hm ²（B）、64 059株/hm ²+145 077株/hm ²（C）时,各试验点可分别达到最高群体产量。玉米+大豆密度组合分别为62 909株/hm ²+149 852株/hm ²（A）、61 499株/hm ²+151 807株/hm ²（B）、62 762株/hm ²+147 108株/hm ²（C）时,各试验点可分别达到最高产值。经模拟得出,在本试验条件下,各试验点玉米大豆间作群体产量≥12 270kg/hm ²、经济产值≥24 000元/hm ²的最佳密度组合分别为玉米59 251~66 437株/hm ²、大豆140 075~161 495株/hm ²（A）,玉米58 927~65 366株/hm ²、大豆144 159~169 203株/hm ²（B）,玉米58 821~66 703株/hm ²、大豆139 315~154 886株/hm ²（C）。合理的密度搭配能有效提高群体产量,获得较高经济产值。     

Model Building and Simulation for Subcritical Pressure Boiler

In order to meet the demand of large scale boiler design and operating optimization, this paper establishes the dynamic mathematic model for domestic 600MW subcritical pressure boiler. MMS software is adopted in the whole process from modeling to simulation. This software make process simple and quick. This model is based on modulariza- tion and the comprehensive physical and chemical process in boiler is considered. Simulation result shows that the re- sponses of this model under different disturbance are coincident to mechanics analysis. The simulation result under ste Pdisturbance can be used to analyze unit changes and provide some guide and it also can supply performance reference data to boiler design.     

The Mathematical Model of Cooling and Heat Transfer for the Solidification of Thin Slab during Continuous Casting Process

In the established model, the cooling differences are considered between the surface of inner radius and that of outer radius, and in the transverse direction of thin slab. And the conception for the effective coefficient of spraying water in continuous casting is firstly put forward. According to different casting speeds and different cooling zones, different time step lengths are adopted. In this model the heat transfer differences are thought over among vertical and curved zones, wide and narrow surfaces an well as angular zone of mould. The method of the corrected equivalent specific heat is used to deal with latent heat. The influence of forced convection is considered on heat transfer. Therefore, the model has higher accuracy and is consistent with the practice.     

玉米渍水模拟模型研究及验证

作物模拟模型是研究作物生态生理过程的新工具,尽管还不完善,但是具有广泛的应用前景.本研究在试验的基础上,根据MACROS模型和文献资料组建了玉米水分模拟模型,加强了模型在渍水方面的功能.经验证,模型能较好地反应我国南方地区玉米的生长发育过程和土壤水分运动,可以用于渍害易发地区的玉米生产研究.并以杭州市为例,应用模型     

Application of Mathematical Experimentation with Computer in Hydraulic Control

Computer mathematical experimentation technology is applied in pressure hydraulic .The non-linear mathematical model of stage mechanical control system is established by the application of computer mathematical software Maple. The computational results agree with experimental data, and precision is satisfied. The mathematical model is the first apply in the control system of stage mechanical elevator. The method has a wide application in computer auxiliary and simulation of mechanical control system.     

多孔保鲜膜MA机理与数学模型研究

针对不同类型的保鲜膜气体分子吸附→溶解→扩散→解析的特征,研究分析了多孔保鲜膜MA机理,建立特征数学模型,从而为保鲜膜的研制和科学的使用奠定了理论基础.