论砼框架结构抗震设计

在砼框架结构抗震设计中,应充分考虑地震的破坏作用,合理设定抗震目标,满足设计的基本要求,采用科学的设计方法,建立有效的抗震机制。     

力传感器综合实验平台的构建

在现有一体化力传感器实验仪的基础上,应用模块化设计思想提出并构建一种综合性较强的具有现代电子测量特点的力传感器实验平台。该平台具有3种不同桥臂电路输出的力传感器检测功能,并可应用计算机实时测量应变片随外测压力变化的曲线,同时可根据初测结果调整修正系数和使用软件数值处理方法进行数据拟合。     

Internal Force Analysis Due to the Supporting Translation in Statically Indeterminate Structures for Different Elastic Modulus

For statically indeterminate structure, the internal force will be changed with the translation of the supports, because the internal force is related to the absolute value of the stiffness EI. When the tension is different with the compression modulus, EI is the function of internal force and is not constant any more that is different from classic mechanics. In the other words, it is a nonlinear problem to calculate the internal force. The expression for neutral axis of the statically indeterminate structure was derived in the paper. The iterative program for nonlinear internal force was compiled. One case study was presented to illustrate the difference between the results using the different modulus theory and the single modulus theory as in classical mechanics. Finally, some reasonable suggestions were made for the different modulus structures.     

Neural network approach for modification and fitting of digitized data in reverse engineering

INTRODUCTIONGrowingglobalcompetitionrequiresmanu facturerstodelivermorecompetitiveproductswithbetterqualityandlowerprices.Reducingtheproductdevelopmentperiodoftheproductisoneofthemostimportantandchallengingtasksfacedbythemanufacturingindustry .Thetradi tionalproductionpatternthatproductsarepro ducedfromthedrawingcannotsatisfytherequirementofmodernmanufacturingindustry .Thedesignofproductscontainingcomplexsculp turedsurfacessometimesstartswithaclaymodelorotherexistingparts.Theprocessofdeve…     

经营文化力:职业院校可持续发展新战略

职业院校文化力是职业学校在长期的办学过程中学校文化发展和文化积累所形成的现实力量。目前存在着科研文化力重理论轻实践,符号文化力重共性轻个性,语言文化力重普教轻职教,价值文化力重技术轻人文,制度文化力重人伦轻人性,产品文化力重成器轻成人的问题。职业院校文化力经营应当设计个性独特的符号,提炼特色鲜明的语言,确定引领方向的价值观,制定和谐发展的规范,创造文明的特色"产品"。     

稀土和磷对过共晶Al-Si合金的复合变质作用

The effect of rare earth (RE) elements on the morphologies and sizes of Si phases in the hypereutectic Al-Si alloys modified with P was investigated.The results show that the addition of La element to the hypereutectic Al-Si alloys can enhance the effect of P element on the modification of the primary Si phases.In the multiplex modification of RE-P,the primary Si phase is refiner and the shape of the eutectic Si is changed from long needle-like to short rod-like.Moreover,the agglomeration rate of the primary Si phase is slowed greatly.Even the melt is held for 6 h,the average size of the primary Si phase is still satisfied.The results analyzed by scanning electron microscope (SEM) indicate that La is richer at A1-Si interface than that inα-Al or primary Si phase.The higher the La content in the Al-Si interface,the smaller the primary Si phase.     

Optimal arrangement of viscoelastic dampers for seismic control of adjacent shear-type structures

The optimal arrangement of viscoelastic dampers (VEDs) used to link two adjacent shear-type structures under seismic excitation was investigated. A two-step optimal design method is proposed. First, optimal parameter expressions of the Kelvin model are used to calculate the optimal stiffness and damping coefficient of the VEDs. Then, using the two-step optimal design method, taking the quadratic performance index as the optimization objective, the optimal arrangement of the dampers is determined. General rules about the optimal arrangement of the VEDs were obtained. The results show that the placement of only one damper between two adjacent shear-type structures should be avoided; if more than one damper is used, they should be distributed on the top and lower floors of the structures. Optimization of the number of dampers had little effect on response reduction. The most important factor was the optimization of the placement of the dampers. Through comparative study, for buildings of equal and unequal heights, the optimal parameters of dampers from parametric studies were shown to match the theoretical results for different numbers and placements of dampers. The level of response reduction was shown to be sensitive to the damping coefficient of the dampers.     

永磁直线同步电机磁阻力优化的设计

The detent force of a permanent magnet linear synchronous motor （PMLSM） is analyzed and the corresponding optimization methods are presented to reduce it. The detent force, which is divided into two components, i.e. resulting from the end effect and resulting from the slotting effect, can be analyzed respectively by the finite element method （FEM）. To reduce the detent force arising from the end effect, several optimal design techniques are utilized, namely, adopting the suitable length and end shape of the primary armature. The detent force resulting from the slotting effect is reduced by means of skewing and adjusting the width of the magnets mounted on the secondary armature, and adopting the fractional slots of the primary armature. The validity of the analytical detent force predictions and the effectiveness of the detent force reduction techniques are verified by the experimental measurements.     

商业银行ATM机混凝土机房改造设计

自动存取款机混凝土机房一般在原有商业银行营业网点内改造而成.因其具有较大集中荷载,同时由于防盗防抢的要求需新增墙体作为维护结构,墙体线荷载也比较大,因此有必要对新增荷载进行分析,进而对楼板、次梁、框架梁进行内力分析、结构验算并进行结构加固.     

我国住宅电气设计容量的现状及改进措施

随着人民生活水平的提高 ,住宅用电负荷增长很快。我国目前的住宅电气设计容量相对偏小 ,在今后的设计中应增加配电回路、插座数量、增大电源干线和支线的截面。以满足未来二三十年负荷增长的需要