Abstract: There are multiple nonlinearities during the course of powder rolling. Considering Material and Geometrical Nonlinearity during powder rolling, a constitutive model complying with an elliptical yield criterion aiming to the powder rolling is constructed based on the Updated Lagrange (U.L.) formulation by which the basic theory of numerical simulation is deduced. The numerical algorithm is discussed and it is implemented into user-subroutines of Marc. With the code, numerical simulation of powder rolling is performed. It is shown that the result of simulation was consistent with that of experiment and the whole result is dependable. The constitutive model and code developed in this work are correct and have good convergence during calculation. Its robustness is to be validated in simulations with complicated geometrical shape and boundary conditions.
Abstract: Short Electric Arc Machining (SEAM) tools were devised for cutting high hardness and strength conductive material. For solution of short electric arc mechanism research and the needs of numerical control melt application, it was necessary to develop a short electric arc CNC machining. The paper introduced the peculiarity and types of the numerical control system’s software and hardware in nowadays. According to the requirement of short electric arc machine an open CNC system was developed in this thesis.
Abstract: The explosion-proof design for coal mine robots that are used to explore environment and rescue after coal mine disaster must be adopted. In order to carry out the explosion-proof design for coal mine robots reasonably, based on the analysis of coal mine robots and their explosion-proof design, the explosion-proof types for robots are studied on. The conclusions are as follows: (1) the mixed explosion-proof design including integrated and partial explosion-proof design can be adopted in the robots design; (2) protection types for robots mainly include flameproof enclosure, pressurized enclosure, intrinsic safety, and combination of them. Based on this, the explosion-proof structures of the mobile systems of a track-type robot and a rocker-type robot for coal mine environment exploration are introduced. According to the different structure of the two robots, the concentrated and dispersed flameproof enclosures are respectively designed for the track-type robot and a rocker-type robot. This paper can provide reference for the explosion-proof design for coal mine robots.
Abstract: In order to solve the problems of aluminum package cleaning a kind of method of milling process for internal surface is proposed. Using three standard cutters which move as planets complete the milling processing for inner cylinder and bottom surface. This method makes the cutters forced reasonably and cutting efficiency is promoted. The adjusting device which is arranged on bigger mills makes the processing size to be changed so the applicability of this cutting method is improved greatly. After research the calculating method of cutting amounts and cutting force are established. The cutting capability of the new method is also analyzed in the paper. By the way the relation curve of cutting amounts and cutting force with cutter rotation rate are given. The achievements above will provide a theoretical basis for the application of this method.显示对应的拉丁字符的拼音
Abstract: This paper presents a new method to estimate the state of charge (SOC) of Ni-MH battery pack in hybrid electric vehicles (HEV). The proposed method establishes the relationship of the SOC to the battery’s voltage, current and temperature by using least square support vector machines (LS-SVM). According to the nonlinear characteristics of a battery pack system, the nonlinear SVM with polynomial kernel are developed for the estimation of the SOC with LS-SVM algorithm. To be more efficient in application, this method is also simplified in this paper. The results have conformed that the proposed method is able to estimate the SOC of Ni-MH battery with high accuracy and noise tolerating ability.
Abstract: Aiming at solving issues of load bearing deformation compensation and sympathetic vibration, this paper takes a large span and heavy load crossbeam of a domestic heavy-type numerical control milling planer for research object, the final purpose is to improve machining precision and stability of the heavy machine tool product. The load curve considering the influence of columns deformation, natural frequency and vibration model are obtained, respectively by the dynamic and static simulation analysis of the crossbeam with the finite element analysis method. Then, the modal analysis results are verified through the model experiment. Lastly, this paper presents an approach by estimating the load curve to improve machining precision, points out the weak links, and provides guidance for crossbeam structure design, optimization and reverse manufacture.
Abstract: In the new period of development of agriculture in China, as an important production element, rural land transfer has been a trend in the market. We first investigate some villagers in Qingyuan County of Zhejiang Province and use the collected data for model construction and fitting by logistic regression. Then we analyze the factors that affect farmers’ demand of joining specialized cooperatives and give some suggestions.
Abstract: Financial ratio is an important indicator to represent the operation performance of an enterprise. Operating performance is defined as some important financial ratios which can indicate enterprise financial with positive operation and growth. The strength and weakness of financial health can not only show the results of operation performance of the organization, but also indicate its growth and potential in the future. However, how to select a set of representative financial ratios is an important issue for evaluating the operating performance of an enterprise. Traditionally, more related researchers have long used statistical methods for handling these problems. However, these conventional methods become more complex when relationships in the input/output dataset are nonlinear. Nevertheless, statistical techniques always rely on the restrictive assumptions on linear separability for the predictive variables, multivariate normality, and many of the models of financial performance violate these assumptions. Therefore, to overcome these existing shortcomings, the proposal proposed attribute selection method to extract financial ratio attributes and OWA based multiple attribute decision making (MADM) to analyze enterprise operating performance situation for stakeholders (i.e., management, investors, employees, shareholders and other interested parties). The financial ratios are collected from the open source information retrieval systems of dataset for publicly traded enterprises in Taiwan stock market from 2008. The proposed model use singular value decomposition (SVD) + ordered weight averaging (OWA) for evaluating enterprise operating performance. At last, the results indicate that the proposed selection attribute can explain enterprise financial situation, and proposed model can objectively evaluate the performance of enterprise.
Abstract: In order to understand the changing tendency of thermal–expansion abilities of used sands in foundry, the four groups of quartz sands were measured in this paper. The influencing laws of baked-times and temperatures on the property of quartz sands were analyzed. And the test results showed that volume thermal-expansion ratio of quartz sands decreases with increasing of the baked-times.
Abstract: The electric meter is a direct tool by which power enterprise charges for electricity Tariff. This paper describes software and hardware designs of MSP430F149 SCM as the core control processor and smart remote transmission three-phase electric meter with the use of power collection special chip CS5460A to complete power measurement. This instrument integrates data monitoring and measurement of the power with LCD. And it can realize the functions of data remote transmission through communication connection between ENC28J60 chip and main controller and easily of real-time monitoring, data collection, system monitoring. This electric meter has some advantages such as powerful function, low cost, strong disturb-resistant ability, etc. and can meet the management requirement of the electricity energy intelligence, which is one of the main development trend in the future. This smart power data collection system will get a good application in the power industry informatization process .