Study on Dynamical Characteristic of Epicyclic Gear Drive with Internal Tooth

The epicyclic gear drive with internal tooth is analysed,a dynamic analysis model which is based on the compatibility conditions of deformation is set up.On the basis of this model,the analysis of dynamics and kinematics is made,and the influence of design parameters on dynamical characteristic is also studied.     

EDM Generating Technology of Quenched Internal Gear

Based on the infroduction of the present process of quenched internal gear, a new technolgy of machining quenched internal gear-EDM generating technology is presented with its principle and machining processes. .     

Optimization of Vehicle Frontal Wheel Orientation Parameters

Based on the theory of multi body dynamic, the paper established the front suspension model of vehicle. The uniform optimization object function, including the tolerance of front wheel orientation angles' practical value and set value under full load, and the changing value of each parameter during wheel fluctuating is put forward. Utilizing this model, the original suspension is optimized and the variation of each parameter with front wheel fluctuation is calculated. The optimized driving operation performance resulted from the analysis and application.     

Process Method of Face-gear Drive with Spur Involute Pinion with the Shaping Machine

In order to research face-gear drives, a face-gear drive with spur involute pinion is considered. The genera, tion of a face gear is based on application of a conventional shaping machine and an involute shaper. The functions of theoretic shaping surface and processing surface about the face gear are deduced. Computer programs are developed for simulation of these surfaces. In shaping time, mutual position of two surfaces, theoretic shaping surface and processing surface, is analyzed by simulation. In the end, the feasibility of the process method is concluded.     

Dynamic optimization design of marine gear transmission system

A dynamic model of transmission system for a marine gear is established considering time-varying mesh stiffness, mesh damping and tooth composite error. The solution efficiency is improved by taking contact line length change of gear pair instead of instantaneous gear mesh stiffness change and making mesh damping and tooth surface equivalent to viscous damping. Multi-objective dynamic optimization design is put into practice to improve the marine gear transmission system using vibration acceleration and mass as target function. The results show that the optimization method can effectively reduce the vibration level and mass of marine gear.     

Analysis of Radial Forces on the Seal Block in a Compound Gear Pump with 3 Idle Gears

By analyzing the pressure distribution between gears and sealing blocks in compound gear pump with three idlers,the resultant hydraulic forces acting on seal blocks are obtained.The conclusion is the unbalanced resultant hydraulic forces are relatively small in magnitude.In the pump,the inner sealing edges are long and so it s Sealing effect is good,but the outer sealing effect is relatively poor because of its short sealing edges.The little unbalanced force pushes the sealing block to te pumping chamber,therefore it is advantageous to meliorating the pump's sealing effect,thereby to improving it's volumetric efficiency as well.     

Multi-object Optimization Design of Engine Mounting System Parameters

A multi-object optimization model is proposed with respect to the completed vehicle in ergonomics,which takes the root-mean-square value of body in multiple work condition and the decoupled energy of engine mounting system as a general object. The optimization values is given. An example shows that the vibration of an automobile can be reduced effectively by choosing proper parameters of mounting system.Moreover, comfort of automobile can be improved.     

The Internal Force Calculation of the Whole-Raising-Scaffold

Because of the different configurations of buildings to be constructed, the arrangement of the whole-raising-scaffold used for practical construction is not always the same, which results in difference of the internal force of the whole- raising-scaffold in application. Based on the abovementioned, in this paper, the design method of the whole-raising-scaffold is investigated, a mechanical model based on the three-span continuous beam is set up, the mechanical characteristics due to the action of various load of the whole-raising-scaffold under the worst working condition is analyzed. Then the calculating method for the internal force of its main structure can be found. Combining the internal force calculated by this method, the security of the scaffold can be verified. The method introduced by this paper can be used as a general method for the scaffold design.     

Dynamic optimization design of gear transmission system for wind turbine

The differential equation which governs the behavior of the gear transmission system of 1.5 MW wind turbine is established. The external excitation caused by wind speed fluctuation is discussed and the internal excitation due to time varying mesh stiffness and comprehensive error is also analyzed. The calculating formulations of the harmonic balance method of nonlinear dynamic equations are presented. Then, the multi objective dynamic optimization model is developed to minimize the value of vibration acceleration and the overall volume. The optimization of a practical example using mixed discrete combined programming is performed. The result shows that the proposed method of modeling and optimization design can effectively reduce the wind turbines gearbox vibration levels and weight.     

The Optimization Design for the Parameters of Capacitor Welding

Through the analysis in this paper,the optimum relation of the discharging current peak interval t m ,the discharging loop equivalent inductance L and equivalent resistance R is obtained.This paper analyze the original discharging loop equivalent inductance L ,which provides an effective method for adjustment and selection of inductance L to realize the optimization energy saving design of the welding machine.     

福建农业竞争力的指标评价与动态分析

首先从省域农业竞争力理论回顾与文献述评入手,笔者在省域农业竞争力评价模型选择和指标体系设计的基础上,通过对福建省域农业竞争力的综合评价与竞争力演变趋势分析,揭示各级指标的变化态势与变化成因,最后提出培育福建农业竞争力的对策研究,为政府决策提供一定参考。     

香梨优斑螟成虫内生殖系统结构观察

[目的]为明确香梨优斑螟成虫的生殖系统的结构特征。[方法]解剖雌雄成虫的内生殖系统并分析。结果发现：雄虫的内生殖系统主要由1对睾丸愈合为一体的近球状精巢,经输精管与2个储精囊相连,储精囊的下端再经输精管与附腺的前端以及复射精管中部相连,其中复射精管前端与附腺前端相连,其下端与单射精管相连, 单射精管末端接于阳茎。雌虫的内生殖系统由2组各4根卵巢的上端连接与悬带,其下端连接两条侧输卵管,两条侧输卵管下端共同连接一条中输卵管,中输卵管末端连接发达的梨形交配囊、受精囊和附腺囊,其中交配囊、受精囊均与导精管相连,附腺囊与附腺相连。[结论]雄成虫内生殖系统由精巢、2个储精囊、输精管、复射精管、2条附腺及单射精管尾端组成,雌虫的内生殖系统由8根卵巢、2根侧输卵管、中输卵管、受精囊、交配囊及较长的附腺组成。     

Optimization Model of Non-rhythm Flow Process and the Dynamic Programming Algorithm

The flowing sequence has important effect to the flow ste Pdistance and the period of non-rhythm flowing construction,algorithmic research of ordering and step distance calculation are always difficult point of non-rhythm flowing construction optimizes studying.An optimization model of non-rhythm flow process is founded,and a common method for confirming the length of flow step was put forward.In order to find the solution of the optimization model conveniently,the optimization problem is transformed to shortest path problem skillfully.A dynamic programming algorithm is given to make the construction project period as shorter as possible,to reduce cost and improve economic efficiency.     

Effect of Dynamic Viscosity on Marangoni Convection in Liquid Bridge With Liquid Encapsulation

The authors establish the physical and mathomatical model of the Marangoni convection in liquid bridge with liquid encapsulation (or two immiscible coaxial liquid columns). A Numerical simulation of the Marangoni convection in liquid bridge with liquid encapsulation is performed by employed vorticity-streamfunction method and the Alternative Direction Implicit scheme in finite difference. The distribution of temperature and flow in two liquid columns is then obtained. The influence law of the dynamic viscosity ratio of the inner liquid to the outer liquid to the Marangoni convection in liquid bridge with liquid encapsulation is obtained.     

Experimental Investigation of "Column with Weaker Beam" Frame and "Column with Equally Strong Beam" Frame

By the way of experiment and analysis of two "one story and one bay" reinforced concrete frames, namely a "beam with weaker column" frame and a "column with equally strong beam" frame, the features of internal force redistribution are investigated and an elementary comparison about bending moment redistribution of three kinds of frames namely the "column with weaker beam", "beam with weaker column" and "column with equally strong beam" is given. Through this comparison, the objective existence of such "three kinds of frame" is proven, the moment redistribution is different for each frame and for the moment modulation, the elastic moment diagram and the difference of the internal force redistribution in different frames should be considered together.     

水稻TRAP-PCR反应体系优化与P-糖蛋白基因片段的分析

对影响TRAP-PCR反应体系的各参数,包括模板DNA、dNTP、Taq DNA聚合酶和引物浓度进行了优化,建立了适合水稻的稳定,可重复的TRAP-PCR反应体系.在20μL PCR反应体系中,含80 ng模板DNA,0.25 mmol/L dNTP,0.75 U Taq DNA聚合酶,5 ng/μL随机引物和7.5 ng/μL特异引物.本研究对P-糖蛋白基因片段进行了克隆并序列分析,为深一步研究奠定了基础.     

客土基盘造林法对滨海盐渍土水盐动态的影响

为了使得客土基盘造林技术在滨海泥质盐碱地造林绿化应用中有充分的理论依据,以河北唐山市南堡开发区盐渍化土壤为研究对象,通过野外试验,研究了客土基盘造林法对滨海盐渍土水盐运移规律的影响,并比较了不同客土配比方式的排盐、降盐效果。结果表明,对照组（未经改造的原状土）土壤含水量变化规律与降水量变化规律相同或稍有滞后,处理组（以不同客土配比方式制作的客土基盘A1、A2、A3、A4）同样受降水规律的影响,但各土层含水量变化幅度差异较大,且峰值的出现时间不同,不同客土配比方式对0~20 cm、40~60 cm土层含水量影响具有显著性差异,对20~40 cm、60~80 cm影响无显著性差异。对照组含盐量变化与含水量变化存在显著负相关关系,观测结束时,返盐程度剧烈;而处理组则无显著相关关系,总体含盐量保持持续降低。4种不同客土配比方式对各土层含盐量变化影响具有显著性差异,平均含盐量均有大幅下降,总体降盐效果：A1>A3>A2>A4,植物根区含盐量下降效果：A1>A2>A4>A3。综合分析,以A1处理方式,即原状土与基质土以1:2配比制作的客土基盘排盐降盐效果最好。