Intensifying Reform on the Operating Mechanism of Building Market

In this paper the necessity and urgency of reforming the operating mechanism of building market are discussed.It suggests that the improvement of quality of builing engineering in China can be ensured in aspects of system and operating mechanism only through the reforms in responsibility mechanism, competition mechanism,supply and demand mechanism,price mechanism,security mechanism and supervision and control mechanism.     

山东省农机合作社运营机制的综合评价——基于层次分析法

山东省农机合作社的发展过程中存在着运营机制不完善等问题,对合作社运营机制的各个组成部分进行综合评价,有利于了解运营机制各个部分对合作社运营机制整体的影响程度。为了评价农机合作社运营机制各个部分对整体的影响,通过采用层次分析的方法,将合作社的运营机制分为内部和外部两个方面,并具体划分了12个二级指标和33个三级指标,研究各个指标对目标层权重的影响,然后进行分析评价。结果表明,内部运营机制相对于外部运营机制而言对农机合作社运营机制的影响要重要的多,其中利益联结和分配机制最为重要,在外部运营机制中合作社与市场的联结机制这一指标最为重要。通过试验研究得出要优化农机合作社的运营机制,最重要的是对利益联结和分配机制、治理机制、和管理机制的优化。     

Exploration on the Formula of Degree of Freedom of Space Mechanism

From the theory that four connecting rods mechanism has flexibility and any closed graphics of plane mechanism has three restrictions, the calculating formula of degree of freedom of mechanism is researched. The result of research indicate that the calculating formula of degree of freedom of space mechanism will be set up if the calculating formula of degree of freedom of plane and spherical surface mechanism are changed a little. The new formula could substitute for 29 traditional calculating formulas of degree of freedom of space mechanism but also the plane mechanism, the multiple rings space mechanism, the open chain space mechanism and mixed chain space mechanism and so on. Because that the new formula is easier and rapider in use than traditional formulas, it is a reliable theoretical calculating formula for calculating degree of freedom of space mechanism.     

Design of a 2 DOF spatial linkage mechanism

A 3D model of a 2 DOF spatial linkage mechanism was built using ADAMS. Kinematic analysis and simulation of the model were performed. The analysis results show that this mechanism meets the design requirements, which provides the basis for further design and control of the mechanism. The main factors that have an impact on mechanism precision subsequently were analyzed and designed. The results show that the sensitivity of the two legs' lengths ranks higher than that of the other design variables. Therefore, the precision design of the bipod is the key point to achieve mechanism precision. The study provides a theoretical foundation for the design, manufacture, assembly, and control of the mechanism.     

油菜割捆机打捆部件的设计与试验

为了解决收割冬油菜与栽插早稻的季节矛盾,提前腾地抢插早稻,设计了一种油菜打捆装置,将该装置配置在4SY-2.2型卧式油菜割晒机割台的左侧,组成油菜割捆机。该打捆装置主要由机架、集禾压缩机构、送绳机构、打结器、捆结离合器、推出机构等组成,通过对送绳机构、集禾机构、放捆机构进行设计计算,确定了打捆装置的主要参数。虚拟样机运动仿真分析表明送线机构、打结器、放捆机构动作配合协调,8.95s完成一个工作循环。利用打捆装置样机进行打捆试验,结果表明装置成捆率为95％,油菜捆平均直径为382mm,油菜秆含水率67.5％时每捆平均重量为5.08kg。本研究为油菜的分段收获提供一种新的方案和配套机具。     

Design of Self-adjusting Planetary Gear Rotation Mechanism Based on Planetary Gear Structures Muster

Self-adjusting planetary gear rational mechanism can eliminate the influence of various uncertain errors in mechanism. Therefore ,it's method of self-adjusting designing is attented by machine designer. For seeking a simple, regular, and widely realizing self-adjusting designing way, this article uses approach of the follow text to design no over-constraint and self-adjusting mechanism. First, the article advances the conception of planetary gear structure muster and it's plotting basis, through using for reference the strategy and method of self-adjusting structure groups in planar linkage mechanism. Second, it designs the self-adjusting planetary gear structure muster, through analyzing the constraint and freedom of planetary gear structure muster. Third, it designs the self-adjusting mechanism, through adding aptitude rotational links outside of self-adjusting planetary gear structure muster. This mechanism can realizes the self-adjusting in the interior of muster and self-adapting in the exterior of muster. This designing plan possesses a series of excellence, such as, theoretical, simple, feasible, widely self-adjusting. Consequently, the mechanism can eliminate the working capability influence of various errors.     

Study of Larger Taper Cutting Mechanism for Wire-EDM Machine

After a analyze for current taper cutting mechanism of NC wire-EDM machine,the paper but forward a new mechanism for larger taper cutting and introducted the working principle in great detail. It has been proved the new mechanism could solve many key techanical problems which current mechanisms had. The new mechanism has been patented. Newly developed NC wire-EDM,DK7725 TC,has been warmly welcome by numerous users.     

植物与尖孢镰刀菌的互作机制研究现状

为了能够更全面地揭示植物与尖孢镰刀菌的互作机制,本文全面系统地总结了尖孢镰刀菌对植物的致病机制,植物对尖孢镰刀菌的抗病机制以及植物与尖孢镰刀菌之间的互作机制,认为尖孢镰刀菌与植物之间主要通过小RNA水平、基因水平、蛋白质与化合物水平三方面进行互作。而在基因组学、蛋白质组学等方法的基础上,进一步结合小RNA分析也将是今后研究尖孢镰刀菌与植物互作机制的主要研究手段。     

豫东平原农用地流转机制研究

目前,中国农用地资源的稀缺性与农用地资源粗放掠夺的经营方式并存,农用地流转迫切要求引入市场机制和宏观调控机制。系统阐述了农用地流转的市场机制和宏观调控机制,在对豫东平原地区农户实地调查的基础上,运用问卷调查法,分析了豫东平原地区农用地流转机制,如在市场机制中出现供求机制失效,价格机制失灵,竞争机制未能形成等情况;在宏观调控机制中出现土地制度和相关环境政策的制约。针对性地提出了完善和创新农用地流转机制的建议。     

乡村旅游业与农村部分产业协调互动的动力机制分析-以贵州为例

本文以贵州为例,从协同论、系统论观点出发,对旅游业与农村产业的内部协调和外部关联的动力机制进行探讨,分析该系统存在的良性协调互动圈层结构的动力机制,提出稳固其良性协调互动应具备的必要条件,构建乡村旅游业与农村各产业部分协调互动的动力机制“七叶水轮机”模型,揭示了外环起到稳定内环良性协调互动的功能。随着外环境变化作用于内环的动力机制表现出显著时空差异,因而该动力模型亦是一动态模型。     

Optimum Design of New-style Impulse Variable Speed Device Based on Invariable Impulse Value

The impulse value of a impulse mechanism has a notable influence on the dynamics capability of impulse variable speed device. Basing on this point, the authors take crank-rocker mechanism in series with slider-crank mechanism as impulse mechanism when we design the impulse variable speed device. The link used to adjust the speed is applied in slider-crank mechanism which has no quick-return characteristic, so the advance-to return-time ratio keeps stable when we adjust its speed. The speed fluctuation also keeps invariable. The new method overcome the default that this kind of impulse variable speed device has a notable speed fluctuation. At the same time, ADAMS software is used to optimize and show the real motion law. From the simulation result we can get the speed fluctuation is down to 18% in the whole process. The change of speed fluctuation is down to 1%. The result is better than other mechanism like this category.     

耕地保护机制建设的机理、特征与挑战探讨

探究了中国耕地保护机制建设的运行机理、基本特征、存在的问题并针对问题提出了相应的对策建议。综合运用了理论分析法、模型分析法、博弈论分析法和图示分析法。研究结果表明中国耕地保护机制建设中行政法律机制占据主导地位、经济市场机制成为发展趋势、多层博弈贯穿始终,市场失灵、政府失灵、社会监督乏力三方面的局限性导致耕地保护机制建设滞后。因此,应改革农村土地产权制度、变革政绩考核制度、规范参与平台、实现经济激励与生态补偿同步化,更重要的是不断探索耕地保护新机制。     

A Game Theory Model on the Information Screen Effect of Compose of Option and Probation Period Mechanism

We have put forward a theory that the probation period mechanism have an information screening function when a company is inviting applications for job, which would be a supplement for the spence model. One of the merits of the model is that it could screen the informations of employee's capacity when there are fewer differences between the capacities of employees. This paper also has proved that option mechanism has a information screening effect and the compose of option and probation period mechanism could decrease the screen cost of a company. We have derived the mathematical Principles of probation period mechanism and the compose of option and probation period mechanism design in the paper.     

贵州省兴义市农村产业融合发展机制探索

产业融合作为当前解决“三农”问题的新思路,目前还在探索的初期阶段,本研究在对国内外大量农村产业融合相关研究进行总结的基础之上,力图通过解剖麻雀的方法,以贵州省兴义市为典型案例,进行中国农村特别是贫困地区产业融合发展机制的探索。结果表明,兴义市在农村产业融合发展实践中,以多元主体培育机制、商业运营机制、利益联结机制、创业就业机制为保障,探索出农牧产业融合、农林产业融合、绿色循环农业融合、旅游扶贫开发融合四大产业融合模式。在对兴义市农村产业融合机制与模式的分析之下,本研究认为农村产业融合的两大要点是多元融合主体的培育与利益联结机制的构建,这会在本质上促进农村社会治理方式的革新,形成农村发展的内生动力。     

Emergency Logistics

The concept of emergency logistics was proposed first in China and aboard first. The emerging background, definition , research content, theory value and application potential of emergency logistics were stated. The government harmony mechanism, mobilization-in-mass mechanism, legal safeguard mechanism and emergency passage mechanism were discussed. Realization way of emergency logistics by constituting emergency disposal organization, establishing technological platform and starting using emergency measures were put forward.     

雌二醇对哺乳动物子宫内膜血管生成调控的研究进展

随着畜牧养殖业的发展,雌性动物的妊娠问题已经越来越突出。值得关注的是,在畜牧兽医产科临床上,妊娠过程中动物子宫血管的生成不足会导致胚胎着床困难增加、流产和胎儿停止发育等问题。近年来临床及实验室对肿瘤血管生成的作用及生成机制的研究颇多,因肿瘤血管的生长机制与子宫内血管的生长机制存在一定的类似性。所以,借鉴肿瘤血管生成的相关研究,了解血管生成的作用及血管生成的机制,为后期进一步研究雌二醇对反刍动物子宫内膜血管形成的机制奠定基础。     

Kinematics and Dynamics Analysis on the Mobile Mechanism of a Micro Piping Robot

A micro piping robot is able to help people finish tasks such as inspection inside a mini pipe. Research on the mobile mechanism of the robot is very important in the robot researching area. The kinematics and dynamics characteristics of the mobile mechanism for a planetary gears driven micro robot have been studied. The operation, the principle and the affect factors of the mobile mechanism have been discussed in detail. In order to drive the robot well, the adhesion and the power of the mobile mechanism should be increased as the influence of its autoeciousness power has been reduced.     

Adjustive Mechanism Design Based on Planar Constraint Uncertainty

For normal planar closed chain mechanism, it is based on ideal planar constraint condition. The authors took crank leader mechanism as an example, and analyzed influences resulted from uncertain factors, such as manufacturing error. The result shows it belongs to statically indetermination mechanism. After analyzing its over-constraint and eliminating it, in this way, it become statically determination mechanism and can be assembled without obstacle. However, in the process of practical running, the mechanism can give birth to new kinematic constraint, frictional constraint and dynamic constraint etc., so over constraint emerges again. Therefore, it is necessary to analyse its adaptability in total running process. The conclusion shows that design of adaptability mechanism normally eliminate geometry over constraint at first, then it is analyzed that whether there is new over constraints from all kind of external constraints in the process of running.     

Dynamic Simulation on the Hoisting Mechanism of a Crane

Considering the difficulties of mathematical analysis and the complex computer programming of numerical methods in solving dynamical problems of the multi-body dynamic system for the hoisting mechanism of a crane, in this paper, a multi-mass-multi-freedom model is set up and the simulation system of the model is built up applying MATLAB/SIMULINK toolbox. The differential equations of the model is solved with adaptive-step fourth-order Runge-Kutta method. In the study, the typical work conditions of the hoisting mechanism, such as start rise from ground, start rise/down in air, brake conditions, were simulated. The dynamic performance of the hoisting mechanism is studied and the results obtained are valuable to practice. This study improves the modeling accuracy of the hoisting mechanism and the results of precious theoretical analysis and numerical computation conclusions. The movement of every discrete body of the system can be modeled applying the methods suggested by this study and more consistent results between model and actual hoisting mechanism can be achieved.     

植物对硫素的吸收、转运及利用的研究进展

本文旨在深入了解植物体对硫素的吸收方式及转运机制,归纳了近年来关于硫素对植物的重要性、植物缺硫的症状、植物对硫吸收和转运的机理,着重分析了硫酸盐的转运机制,硫酸盐进入植物体内经过活化、还原和半胱氨酸的合成过程,总结了国内外关于硫酸盐在植物体内部的变化、各种存在形式的利用机制,指出该领域仍存在的一些问题以及未来的研究侧重点,为相关研究奠定基础。