用PLC技术改造普通机床电气控制系统

用PLC技术改造要了解和分析被控对象的工艺条件和控制要求、确定I/O设备、选择合适的PLC类型、分配I/O点、设计应用系统梯形图程序、将程序输入PLC、进行软件测试。     

接近开关输出电路的转换方法

文章介绍了接近开关的工作原理,根据不同的PLc输入电路类型选择适用的接近开关,并阐述NPN型与PNP型接近开关输出电路的转换方法。     

浅谈PLC梯形图的设计方法

本文主要研究PLC梯形图的设计,围绕其常用设计方法展开讨论,阐述了各种设计方法的特点、使用场合及注意事项。     

三路智力抢答器的PLC控制

该抢答器可作为智力竞赛的评判装置。根据应答者抢答情况自动设定答题时间,并根据答题情况用灯光、声音显示。在工作人员的操作下可对答题情况进行加10分或减10分的操作。本文结合实际应用,用数码管显示分值,在分值的显示上我们采用ZCP、SEGD指令相结合。使分值的显示即准确、思路又清晰。本程序适合于三菱系列的PLC。     

输出驱动—输入促成假设下的高职英语翻转课堂设计

提高高职学生英语输出的能力是当今时代对高职英语教学的要求,本文以输出驱动—输入促成模式为指导,以翻转课堂模式为基础,对高职英语教学课程进行设计,以提高高职学生的英语语言输出能力.     

巧用输入与输出活动切实提高大学英语课堂教学质量

学习语言的过程实际上就是语言输入、输出相互影响、相互促进的过程。在大学英语教学过程中,处理好输入与输出之间的平衡关系,进而在一定程度上巧妙运用各种输入、输出活动,可以有效地提高教学质量,并且直接关系到大学英语教学的成败。     

巧用输入与输出活动 切实提高大学英语课堂教学质量

学习语言的过程实际上就是语言输入、输出相互影响、相互促进的过程。在大学英语教学过程中,处理好输入与输出之间的平衡关系,进而在一定程度上巧妙运用各种输入、输出活动,可以有效地提高教学质量,并且直接关系到大学英语教学的成败。     

巧用输入与输出活动 切实提高大学英语课堂教学质量

学习语言的过程实际上就是语言输入、输出相互影响、相互促进的过程。在大学英语教学过程中,处理好输入与输出之间的平衡关系,进而在一定程度上巧妙运用各种输入、输出活动,可以有效地提高教学质量,并且直接关系到大学英语教学的成败。     

Assessing the Behaviour of Non-Survey Methods for Constructing Regional Input–Output Tables through a Monte Carlo Simulation

The paper aims to analyse the behaviour of a battery of non-survey techniques of constructing regional I-O tables in estimating impact. For this aim, a Monte Carlo simulation, based on the generation of ‘true’ multiregional I-O tables, was carried out. By aggregating multi-regional I-O tables, national I-O tables were obtained. From the latter, indirect regional tables were derived through the application of various regionalisation methods and the relevant multipliers were compared with the ‘true’ multipliers using a set of statistics. Three aspects of the behaviour of the methods have been analysed: performances to reproduce ‘true’ multipliers, variability of simulation error and direction of bias. The results have demonstrated that the Flegg et al. Location Quotient (FLQ) and its augmented version (AFLQ) represent an effective improvement of conventional techniques based on the use of location quotients in both reproducing ‘true’ multipliers and generating more stable simulation errors. In addition, the results have confirmed the existence of a tendency of the methods to over/underestimate impact. In the cases of the FLQ and the AFLQ, this tendency depends on the value of the parameter δ.     

Diversity Analysis of Structural Change Based on the Canadian Input–Output Tables

This article presents some of the results of a study conducted at Statistics Canada that involved the analysis of the variability through time of input–output structures. All structures have been analyzed in current and constant prices over the period 1961–84, but only the results about the industries' input structures in current prices are reported in this article. Structural changes are assessed over time horizons of 1, 2 and 5 years, using the Kullback, cross-entropy index formula. Structural changes in the current prices input structure are decomposed into a price and a quantity component, following a new decomposition of the entropy formula. It is shown from that decomposition that the traditional analysis of the variability of constant prices input–output structures may be quite misleading. The authors have found that structural changes generally follow a smooth path through time and tend to be cumulative in the long run, with some cyclical fluctuations in the short term. Some of the structural changes appear to be due to statistical events (establishment moves across industries, changes in methodologies, etc.) rather than reflecting real phenomena. The quantity component of structural change appears to be more important than the price component in almost all time periods and time spans, except when the Canadian economy was subjected to important price shocks during the 1970s.     

Some Applications of Input–Output Analysis in a Gold Mine

In this paper, some applications of a mixed physical-financial input–output model for a large gold mine in China are described. This mixed input–output model is a basic part of the mine's decision-making system, called an interactive and hierarchical multi-objective feedback decision-making system of the gold mine's production and management. The model is used for the following: (1) to analyze quantitatively how the changes in the economic, technical and geological factors affect the mine's production and management; (2) to search for a series of bottleneck components in the mine when the capacities of some components of the mine change; (3) to optimize mine planning with the help of mathematical programming (linear programming, 0–1 programming) and computer simulation.     

资本投入对我国经济增长的影响——基于拓展的MRW框架的分析

本文基于同时包含物质资本、教育资本、健康资本和R&D资本的拓展的MRW框架,根据我国31个省(市、自治区)1998~2007年的数据,考察了资本投入对我国人均实际产出以及经济增长的影响。研究发现,物质资本投资、教育投资和R&D投资对我国人均实际产出以及经济增长具有显著的促进作用,健康投资对产出水平有显著的促进作用,但对经济增长的影响不显著。在此基础上,本文估算了我国总量的生产函数以及资本投资的回报率。此外,本文还将全要素生产率内生化,进一步考察了资本投入对我国人均实际产出与经济增长的影响。     

Comparison of Input–Output,Input–Output + Econometric and Computable General Equilibrium Impact Models at the Regional Level

Economic impact studies are a common practice—indeed, a necessary prerequisite in many cases of project development—in Australia. Although input–output (IO) is still regarded as the ‘bread-and-butter’ model for these types of study, attention in recent years has turned towards more sophisticated models, the main contenders being integrated IO + econometric and computable general equilibrium models. All these models, which are often promoted as substitutes, exhibit characteristics which are theoretically and empirically appealing, yet questions have been raised with respect to the different approaches, with apparently little awareness at the practitioner level as to the extent of these differences. This paper compares the three models and demonstrates that the differences can be quite substantial, even when the models rely on the same database and are subjected to the same impact scenario.     

我国货币政策冲击对实际产出周期波动的非对称影响分析

本文运用马尔可夫转移模型和冲击响应分析等方法，检验了我国货币政策冲击与实际产出之间的动态关系，发现货币政策冲击对产出的影响存在明显的非对称性，并且产出对货币冲击的反应存在着“低度反应”和“高度反应”区制；我们通过时变转移概率方法进一步检验描述非对称反应的三种可能形式，即关于货币政策冲击方向、冲击规模和经济周期阶段的非对称形式。     

Compilation of Input–Output Data from the National Accounts

In this paper, a new method is presented to derive an input–output table from a system of make and use tables. The method, which we call ‘activity technology’, is mathematically equivalent to the well-known commodity technology, but chooses another unit, i.e. the activity. We will argue that, in the activity technology model, negatives can only arise from causes such as heterogeneity and errors in the data. To apply the activity technology, very detailed make and use matrices are required, as well as additional data on the input structures of certain activities. We will describe a method that can incorporate this additional data within the activity technology framework. Statistics Netherlands has adopted the method     

Price-endogenized Input–Output Model: A General Equilibrium Analysis of the Production Sector of the Japanese Economy

This paper considers a generalization of the open Leontief model, by endogenizing the input coefficients on the basis of the neoclassical multi-sectoral produc-tion function. The adopted production function is of the two-level CES type, which is quite effective for avoiding the multi-collinearity problem. As a result, the estimates obtained are quite stable, satisfying the quasi-concavity conditions of the production function for all the sectors. Comparative statics based on the Jacobian of the excess supply function for each commodity market reveal that, owing to the factor substitution the effect of an increase in the final demand on the level of the production is significantly smaller than that which occurs in the open Leontief model with fixed input coefficients.     

基于PLC的立体仓库运行系统

介绍了可编程控制器（PLC）的基本结构及立体仓库的工作流程，论述了用PLC控制自动化立体仓库以达到仓储技术的全面自动化的制作流程及设计思路。     

中国的潜在产出、产出缺口及产量--通货膨胀交替关系--基于"Kalman滤波"方法的研究

本文介绍并运用“Kalman滤波”方法估计1979-2004年间我国的潜在经济增长率和产出缺口,然后根据这些结果检验了我国经济增长与通货膨胀率之间的交替关系、社会的通货膨胀预期对经济的影响、决定产出缺口大小的影响因素等,最后利用研究结果对我国2005年的经济发展进行了预测。