Study on CAD Approach in Die''s Manufacturing by Sheet Metal Layer for Layer through Gluing

Based on the principle of material incress manufacturing, a new idea of the die's construction manufactured by sheet metal layer for layer through gluing is presented, and a CAD approach of the die's three-dimensional surface creating and the scattering handling is discussed in this paper. It is also analysised that layer's separation of the three-dimensional CAD model, change and transmission of separating layer's data, and mechanical properties of die's construction manufactured by sheet metal layer for layer through gluing. The results of the research indicate that die's manufacturing by sheet metal layer for layer through gluing is feasible and effective one of material incress manufacturing technical.     

Research on Machining Last by Numerical Controlled Last Carving Machine

System structure of last CAD/CAM is described. Then machining principle of system output device named numerical controlled Last Carving machine is introduced. Furthermore, we lay stress on analyzing machining programming method making use of direct numeric definition. Special disposal is taken on step error and working frequency of step motors so that not only error accumulation is avoided but also step motors always work in the best frequency range. As a result, machining precision and speed of last are both enhanced as well as step motors' working safety is guaranteed.     

A Novel Method Based on Support Vector Machine for Defect Identification

The traditional fault detection suffers from complicated process, low accurate ratio and off-line implement. The improved methods of defect recognition by artificial neural networks (ANN) can lead to the problems of overfit and bad generalization because of finite samples. With a view of data mining and technique parameters directly, the new approach using support vector machine classification algorithm after removing redundant parameters by rough set theory and eliminating noise of data to identify the defects is discussed. The results of a experiment show that unlike conventional and ANN recognition methods the new technique performs better than conventional evaluation ones with advantages of high efficiency, lower cost, easy implement on-line, excellent generalization and so on. The approach provides a novel technique means for nondestructive defect identification of various products.     

A Reference Framework for Information Integrating of CIMS Based on the Object-oriented Method

Based on the object-oriented method,according to the Enterprise model of Information Integrating,by means of the idea of Encapsulation and Inheritance,a common reference framework for Information Integrating of CIMS is presented. This kind of integration is not only used for the share information,but also ready for Function Integrating and the whole construction of CIMS. Moreover,the system developed based on this model can be reused for many times. The developing circle of CIMS can be apparently shortened,too.     

New Iterative Method of Ventilation System'' s Wind Quantity for Electric Machines

Solving methods of wind quantity in complex ventilation meshes which includ wind pressure source are researched. A general matrix model of ventilation meshes and new iterative formulas are proposed. Two computing examples are given and the results shows that each branch' s wind quantity can converge the stable value by several times of iteration for any iterative initial value. The proposed model is suitable for wind quantity computation with complex ventilation structure of electric machines.     

基于标准化方法的遵义东南部地区农业土壤重金属污染评价

为了评价遵义东南部地区农业土壤的重金属污染状况,以Sc为标准化元素,应用标准化方法建立了遵义东南部地区农业土壤重金属Cd、Pb、Cr、Hg、As的环境地球化学基线模型,在此基础上运用富集因子法评价土壤的重金属污染状况。结果表明,该区域农业土壤中40%受到Cd的污染,53%受到Pb的污染,60%受到Cr的污染,40%受到Hg的污染,40%受到As的污染,污染级别均为1级,表明土壤受到了轻微扰动。     

Model of Information Integrating in CIMS Based on the Object-oriented Method

Information integrating is the most important key to CIMS,which is the base of the function integrating and all others.Because of so many kinds,so complicated structure,so many different sources and uses that the information in CIMS has,it is necessary to build a popular Information Integrating Model. The model of information integrating in the thesis bases on the enterprise model,which is presented by ISO(International Organization for Standardization).According to the object-oriented method,the process of modeling begins with classifying the information,and then describes the definition of the attributes and the structural relation of those objects. By means of the idea of Encapsulation and Inheritance,the destination of information integrating can be arrive and the model of information integrating can be set up. The model which is based on the share information is helpful to finish the function integrating and the whole CIMS' construction. Moreover,the system which is developed following such program can be reused for many times and the developing circle of CIMS can be apparently shortened,too.     

Study on Experiment Methods for the Mechanical Properties of Expanded Metal Mesh and Their Results

Through comparison of four experiment methods, the basic properties of expanded metal mesh are studied on the mesh with special form of oblique wires and nodes. Moreover, the property index for design is obtained after analyzing the 4 experiment methods, which supply the experimental and theoretical basis for the application of this material to buildings. It is suggested that such specimen can be used as standard one for determining the property index.     

A New Method for First-Order Analysis of Thin-Wall Member

Based on the calculation procedure of dynamic coordinate method, the examples in this paper prove, that the first-order stress of thin-wall member is easily calculated with the new method and that a new method of first-order analysis is easily comprehended.     

强筋型优质小麦新品种陕253的选育及其主要特征特性研究* Ⅰ 强筋型优质小麦新品种陕253的选育研究

陕253是西北农林科技大学农学院小麦研究所育成的优质小麦新品种，其组合为陕229/陕213，它集优质、丰产、早熟于一体，具有面团形成时间和稳定时间长等突出的品质特征。其成功选育说明：优质与高产能够完美结合；选择农艺性状优良互补、遗传背景复杂、品质较好的双亲是育成优质品种的基础；有效的品质测试手段是选育优质品种的保障。     

钢渣对酸性重金属污染土壤的修复研究进展

改良剂原位固定技术是重金属污染土壤修复的重要措施,其中选择经济有效的改良剂是该技术的关键。本研究主要介绍了具有碱性富硅特性的炼钢副产品钢渣对酸性重金属污染土壤的修复效果及作用机制,以期为重金属污染土壤修复提供理论参考。首先分析了改良剂固定技术的研究现状;然后介绍了钢渣的主要理化性质,阐述了其对污染土壤pH及重金属活性的影响;最后论述了钢渣对喜硅植物生长的促进作用及对其重金属耐性的增强机制。通过分析表明：施用钢渣能同时调控重金属在土壤和植物2个系统中的迁移和转化,能够减少重金属向食物链的迁移,在酸性重金属污染土壤修复实践中具有重要的潜在应用价值。     

水旱交叉选育抗旱高产小麦新品种的研究

在抗旱高产小麦新品种选育中，采用渐近杂交法使目标性状得到有效的组合，采用水、旱地交叉选育法，为杂种后代基因型的潜在遗传特性的充分表达和选择提供了条件，使自然选择、人工选择和定向培育三者紧密地结合在一起，加大了选择压力和频率，提高了选种质量和效率，提高了选种质量和效率，为选育抗旱、高产、稳产小麦品种提供了一种新方法。     

一种检测棉花黄萎菌毒素致萎性的新方法-叶片针刺涂抹法

用针在棉花叶片表面0.5 cm2的面积上刺15~20个小点,然后将黄萎菌毒素溶液涂抹于针刺部位,观察记载处理部位的萎蔫程度,由此检测黄萎菌毒素对棉花致萎性的强弱。利用层析纯化的黄萎菌V991毒素对棉花的致萎性试验表明:棉苗的子叶为最佳接种部位,毒素对陆地棉感病品种鄂荆3号的致萎下限为7.3μg,接种24 h即可表现萎蔫症状。用8个不同致病力黄萎菌系的培养滤液(简称滤液)针刺涂抹3个不同抗病性陆地棉品种,同时设置相应毒素浸泡参比试验。结果表明,利用培养滤液,即可以快速、准确地检测滤液的致萎力强弱,该方法既可用于棉花品种资源对黄萎病的抗性鉴定,又可用于比较黄萎病菌的不同生理型。     

基于模糊数学法的新建绿地土壤物理性能评价

城市绿地土壤的物理性能影响着城市生态系统的运行,为了研究城市绿地建设过程中不同层次土壤的物理性能,以西安植物园新区为典型案例,选取容重、总孔隙度、毛管孔隙度、非毛管孔隙度、田间持水量、自然含水量等六个指标,结合模糊数学法以及SPSS19.0与Excel软件对各层土壤的物理性能(Q)进行评价。结果显示,西安植物园新区表层土壤(0-25cm)、浅层土壤(25-50cm)、中层土壤(50-70 cm)、深层土壤(70-90cm)的Q值分别为21.69、61.24、71.19、66.89;分别处于极差水平、较差水平、良好水平、较差水平。平均Q值为55.25,处于较差水平。表层土壤与浅层土壤Q值过低的原因在于重型机械的重复碾压,碾压力对中层土的影响较小。随着土层深度的增加,深层土壤的Q值相对中层有所下降。各影响因子的权重比较显示,土壤容重是影响各层土壤物理性能优劣的重要因素,但随着土层的加深,土壤容重的权重逐渐降低。自然含水量的权重随着土层的加呈现逐步上升的趋势。     

基因库中多花菜豆种子繁殖更新方法

取材于有特殊经济价值、常异花授粉作物多花菜豆,研究基因库中种子繁殖更新方法。连续３年,选用４个品种,设２５～２００株５种不同群体,采用人工授粉等５种授粉方法,以自然条件下风、虫自然传粉为对照。从农艺性状调查,染色体观察及同工酶分析方面进行研究。人工授粉后无变异现象,但结实率很低,只有２．１％左右,且成本昂贵;群体内昆虫自然传粉结实好,幼苗和籽粒变异率为１．３％和１．２％;单花序或单花套袋自交基本不结实,只有个别品种能结实（１％～２％）;对照生长最好,结实率最高,变异率也最大（幼苗１．７％、籽粒１．９％）;全封闭网棚蜜蜂传粉生长正常,变异率低（幼苗０．４％、籽粒０．７％）,成本也较低;全封闭网棚自然传粉的产量低,折合每公顷只有３７８ｋｇ,其成本高于网棚放蜂者。从而明确了在内蒙古呼和浩特繁种,自然条件适宜可减轻选择压力;以全封闭网棚蜜蜂传粉效果最佳,可减少变异频率,防止外来花粉掺入;其群体大小一般以５０株为宜,是繁殖更新多花菜豆基因库种子切实可行的方法。     

一种新的棉花黄、枯萎病快速接种方法的研究

 3种不伤根的棉花黄、枯萎病接种方法,即全生育期的田间病圃鉴定法、液体培养棉花苗期孢子悬浮液浸根法和土壤种植棉花苗期孢子悬浮液灌根法进行对比,结果表明,液体培养棉花苗期孢子悬浮液浸根法（接种浓度为10⁷个分生孢子·mL^-1）全周期只需要30 d。通过这种方法,不仅可以鉴定出棉花品种对黄、枯萎病菌的抗、感病性,还可以鉴定不同黄、枯萎病菌菌株的致病力。对比不同浸根接种时间（10 min、20 min、30 min、40 min、50 min、60 min）对结果的影响,发现浸根接种40 min可加快发病,鉴定结果和田间病圃鉴定的比较一致。     

A New Method for Measuring Bonding Shear Properties of Adhesives on Steel Substrates

Single-lap-joint adhesively bonded metal specimen which is the national standard experimental method in use has an extremely non-uniform distribution of shear stresses along the joint, and tensile stress concentration of high values is produced on the steel substrate interfaces. Therefore the test result, which is not the real bonding shear strength between adhesive and steel substrates, can only be used as a test index for qualities of adhesives not the strength criterion for load is capacity evaluation. The combined bonding disc specimen is adopted for measuring bonding shear properties of adhesive on steel substrates, has a very uniform distribution of shear stresses in adhesive and along the bonding surfaces of steel substrates, of which the uniform coefficient is greater than 0.97. Furthermore, when adhesive joint is treated as an arc and steel substrates are chamfered at both ends of the joint, tensile stresses on the bonding surfaces can be reduced to less than 20 MPa which can hardly cause tensile failure. Thus, the results of combined bonding disc specimens can actually represent the real bonding shear strength or bonding shear-compression strength between adhesive and steel substrates, which can be used as strength criterion for load capacity evaluation of bonding members.     

A Preliminary Survey on Analysis Method of Building Structures Under Post-Earthquake Fire

Considering the impact of post-earthquake fire on building structures in structure design, an analysis method is proposed to analyze and simulate the response of building structures under post-earthquake fire. Based on the seismic response and thermal stress analysis, this method considers the structure seismic damage through a simplified seismic damage model, and the simulation of the response of building structures under post-earthquake fire was reached by linking the heat transfer analysis and thermal stress analysis to the results of seismic damage. A single-storey concrete frame and a multi-story concrete frame were analyzed with this method and compared with experimental results of the same concrete frame under fire without seismic damage. It is shown that the collapse mode may change for seismic damaged structures and the fire resistance decreases with the increasing of seismic damage degree.     

A New Fault Location Method Based on Two Terminal Information of Self synchronous Rectification

In accordance with the high and extra high voltage long distance transmission line,this paper presents a fault location method based on two terminal information of self synchronous rectification.We adopt the long transmission line model,consider the effect of distribution capacity and can correct the sample phase angle difference in the real time btween two terminals.So that this method can avoid the fault location error owing to asynchronous message on the two terminals.Tested by a lot of simulations,the results are very satisfied.