Reconstructing NURBS Surface with Features

1 Introduction Reverse engineering (RE) is ani mportant method in constructing a CAD model froman existing physicalpart during part or product design. Whenthe digitized points are available ,the CAD model could be constructedby NURBS curves or surfaces fitting, whichis a commonly available and widely used method.Many efforts have been made in constructing CAD models by fitting NURBS curves and surfaces topoints[1 ,2]. As constructing NURBS surface is usually not a stand-alone projec…     

Simulation on Mechanical Behaviors of Oil-film Bearing Sleeve by Elastic Interference Fit

1 Introduction Under heavy load case ,the performances of sleeve and bush are of vital i mportance to ensure the safety andreliability of oil-fil mbearing[2]. To keyless sleeve by interference fit ,in addition to enough strength,stiffnessand adhesive force ,its other i mportant considerations are periodic set-up and dismount so as to ensure the safetyof bearing. Abnormal wear and adhesion damages are usually occurred by the status and level of stress in bothjoint sections . Hence ,stress and d…     

A Solution of Drawing Straightening Roller Curve by Conjugate Revolving Quadric Theory

1 Introduction In the process of rolling,cooling and shearing,the rolled bars will display variable degrees of plastic defor-mation andinner residual stress because of suchfactors such as the inhomogeneity of plastic deformation,heat-ing,cooling,shearing,transportation and stockpiling. Therefore ,before application as qualified products ,theproduct must be straightenedin straightening machine .To straighten coil bar ,the straighteningscheme of cross rolls ,which madethe rolling material beinge…     

Design of a Mobile Mechanism for Missing Miner Search Robots in Underground Mines

1 Introduction It is important to search and locate missing min- ers promptly, rapidly and accurately after disasters occur in underground coal mines[1–2]. The missing miner searching robot (MMSR)[3] for underground mines is an autonomous mobile robot used for searching and locating missing miners and detecting the surrounding parameters of the dangerous under- ground coal mine environment after mine disasters. In areas where mine rescue team members cannot go, MMSR can replace rescuers to…     

A Method of Job Scheduling on SMEs' Key Equipments Based on Hybrid Multi-attribute Decision Making

An analysis of the key factors affecting on the single production process job scheduling of the parts waiting for be- ing processed on the key equipments for SMEs (Small Manufacturing Enterprises) is given in this paper,which include interval number,real number and uncertain linguistic value.A kind of hybrid multi-attribute decision making method for the single pro- duction process job scheduling is presented in this paper,that the parts are firstly sorted about each factor,and then the total evalu- ative attributive value of each part is calculated with the method of weighted arithmetic average,and thus the part with the highest total evaluative attributive value is chosen for being processed firstly.The mathematic model corresponding to the method is set up in this paper.An example is studied in this paper,and the results of the example testify the correctness of this model.     

Evolutionary Topology Optimization for Heat Conduction Fields

An effective evolutionary method for solving the structural topology design problems of heat conductive fields is presented in this paper.The topology optimization model based on minimizing the heat transport potential capacity dissipation of heat conductive field is then established and the corresponding sensitivity of objective function is derived to determine which elements would be removed of the heat conductive field for having the increment of the objective heat transport potential capacity dissipation minimized.A Filtering technique is employed in sensitivity field to eliminate numerical instabilities in the evolutionary procedure. Numerical examples are presented to demonstrate the validity and the engineering applicability of the evolutionary method by con- trast with SIMP method,meanwhile we can come to a conclusion that higher speed of convergence and clearer optimal topology dis- tribution without intermediate elements can be attained by using evolutionary strategy,with the results laying a reliable foundation for the subsequent shape and size optimizations in thermal engineering.     

QE and Suns-V_(oc) study on the epitaxial CSiTF solar eelis

~~QE and Suns-V_(oc) study on the epitaxial CSiTF solar eelis1. McCann, M. J., Catchpole, K. R., Weber, K. J. et al., A review of thin-film crystalline silicon for solar cell applications Part 1: Native substrate, Solar Energy Materials & Solar Cells, 2001, 68: 135-172. 2. Catchpole, K. R., McCann, M. J., Weber, K. J. et al., A review of thin-film crystalline silicon for solar cell applications Part 2: Foreign substrates, Solar Energy Materials & Solar Cells, 2001, 6…     

In situ formation of nanometer-scale TiO_2/SiC functional compositional film on carbon fiber

In order to have a specific functionality or to act as a protective layer for the ce-ramic material, ceramics were often prepared with the surface layer of different compo-sition from the bulk. The methods were used as follows: (1) the chemical vapour deposi-tion; (2) the powder methods such as slip cast or dry processing; (3) the thermal chemi-cal reaction. These methods have their own advantages and disadvantages. But most ofthese processes were not easily adapted to coating samples in the f…     

Preparation and Characterization of Red Emitting Phosphor Ba_xCa_(3-x)(PO_4)_2∶Ce, Mn

Preparation and Characterization of Red Emitting Phosphor Ba_xCa_(3-x)(PO_4)_2∶Ce, Mn     

Corrosion resistance of plasma sprayed NiCrAl (ZrO_2 Y_2O_3) thermal barrier coating on 18-8 steel surface

1INTRODUCTION Austeniticstainlesssteelisdevelopedtocom pensateforpoorcorrosionresistanceofmartensite stainlesssteelandoverlargebrittlenessofferrite stainlesssteel.Basicconstituentsofitstypicalal loyare18%Crand8%Ni(massfraction),which isusuallycalledas188s…