APPLICATION OF SUB-ELEMENT AND MICRO-ELEMENT IN BEM WITH ROLLER BEARING LOAD

Aiming at the discontinuous traction on contact elements of roller bearing, new concepts of sub- and micro-element are put forward. In the sub-element and micro-element, traction influence coefficient has been modified, which is calculated by the former boundary element method (BEM) with roller bearing load. Hence, three-dimensional distribution of load on roller bearing is calculated accurately. In practice, it has been proved that this method has higher calculation accuracy. An effective numerical method is offered for analyzing load characteristics of roller bearing to improve service longevity of roller bearing and operation efficiency of rolling mill.     

An Effect of Temperature and Notch Geometry on Correlated Toughness of a Stainless Steel

To determine the toughness of materials, Charpy V notch test has been widely used over the world. Originally, the Charpy-V or U tests were used mainly as a quality control tests. In this paper, effects of temperature and notch geometry on variation of toughness/yield stress ratio were investigated. The experimental work has been performed on austenitic stainless steel 316L using Charpy tests and carried out at temperature range from 20 ℃ to 250 ℃ on different dimension of V- and U-notch specimens. Energy of fracture was determined directly from machine tests. Furthermore, Barsoum correlation has been applied to determine toughness/yield stress ratio as function of temperature. In addition, several parameters were investigated namely specimen thickness and notch cut angles. U-notch specimen offers a high resistance comparatively to the V-notch and that toughness depends on temper situation and orientation of notch relative to the rolling direction.     

DEVELOPMENT OF A 3-DOF MICRO-POSITIONING WORKPIECE TABLE

In order to achieve active grinding control, a novel numerical control micropositioning workpiece table with a resolution of 6 nm has been developed. The table is driven by three piezoelectric actuators mounted on the base. An elastic structure with three half-notch flexure hinges is designed to apply preload to the piezoelectric actuators. The position of flexure hinges is also elaborately designed with consideration to reduce the bending deformation of the moving part. Three capacitive sensors are used to form close loop control system. Considering the table as a damped 3-DOF mass-spring system, the models of static and dynamic stiffness and error owing to the action of external forces have been established. In order to make the table have high resolution and positioning accuracy, an error compensation algorithm is implemented by using the established models. The experimental testing has been carried out to verify the performance of the workpiece table and the established models of the micropositionin     

BLET:Battery Lifetime Enhancement Technology

<正>In recent years,mobile devices and high-hearth because of the multifunctional,battery capacity has been increased.In this paper,without the overhead by using the battery discharge characteristics,and application of technology to extend the battery life is explained. Experiment H.264 video transmission to take some losses and extended battery life was achieved.     

Rubber Industry Significantly Enhances the Ability of Independent Innovation

In recent years, the level of independent innovation and research and development strength of China＇s rubber industry has been improved significantly and the achievements in 2007 were particularly notable. China＇s rubber industry has got a series of original new innovations and master part of the international forefront technology, at the same time, a new generation of green tire for environmental protection and aviation radial tire and other new products are shown on the market faster.     

单体烃系列碳同位素标准物质研制

In order to meet the accurate δ ^13C measurement of organic individual compound on chromatography analyzer and isotope mass spectrometry, the standard material of C12～C6 nalkane serial isotope has been prepared. The prepared solution Of C C12～C36 in which n-hexane is used as solvent is even and stable. The standard material has been measured in two ways by all three laboratories, and the uncertainty degree of single measurement result is 0.9%.     

AUTOMATIC SEAM TRACKING SYSTEM OF SUBMERGED ARC WELDING BASED ON FUZZY-P CONTROLLER

An automatic seam tracking system used in submerged arc welding is presented. In the system, the linear CCD vision sensor is installed in front of the welding torch. Laser structure light emitted by the semiconductor laser irradiates on a slant to work-piece surface and forms a structure light strip on work-piece surface. Scatter light of the strip is received by linear CCD on top of the seam and the image information of seam can be obtained. By way of image processing and applying Fuzzy-P controller in tracking process, automatic seam tracking has been realized accurately. Anti-disturbing ability of the system to work-piece surface status has been enhanced largely by classified microadjus-tment of torch height.     

Boiler level control system based on ControlLogix5550 PLC

<正>This paper is a research design based on EFPT process control device.In the design,actual industry field has been simulated and corresponding modelling has been carried on for the boiler level system.Then the appropriate PID parameter has been sorted out and ControlLogix5550 PLC has been used to control the entire boiler level system. At last,a corresponding control interface has been established and the boiler level has been under a safe and accurate control.     

TECHNIQUES ABOUT DIRECT OPTIMIZING CONTROL OF GREEN SAND QUALITY

0 INTRODUCTION*Green sand casting is still one of the main methods used in the world at present and the green sand properties impair the qualities of castings directly. It has been proved that more than 60% of casting defects relate to mold quality and the most important reasons are inadequate sand strength and permeability. In practical production, the molding method does not often change and the mold quality will be affected by green sand properties. In recent years, various techniques …     

MALDI-TOF-MS分析基因重组糖蛋白rhEPO的一级结构

Matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS) is a rather new ‘soft ionization’ techniques. Because of its high sensitivity and accuracy, it has been widely used in detection and characterization of macromolecules such as peptides, proteins and olignucleotides. It also has been applied successfully in the analysis of posttranslational modification of proteins, such as phosphorylation and glycosylation. Compared with the conventional chemical methods, mass spectrometry is simple, rapid and does not require radiolabeling. In this research, a systematic method to analyse glycoprotein by MALDI-TOF-MS was developed. A practical sample--recombinant human erythropoietin was analysed by the method. The molecular weight, content of carbohydrate and glycosylation sites of the glycoprotein were determined by MALDI-TOF-MS, combined with the endo-glycosidase digestion and peptide mapping. The experimental result shows that MALDI-TOF-MS is a very powerful technique in the characterization of glycosylation proteins.