三峡船闸通过系统与智能运行模式探讨

三峡船闸通过系统是一个以时间为基准轴的伺服过闸时间过程系统。从系统工程的角度探讨三峡船闸过闸作业过程,分析三峡船闸通过系统智能化的核心需求,提出该系统的智能运行平台的技术框架与主要功能,为三峡船闸及类似船闸的智能运行平台建设提供理论支撑。

数字印刷系统的设计原理(下)

五、多次通过系统与一次通过系统 1.多次通过系统 当数字印刷系统中只有一个成像装置时,如果要实现彩色印刷,则纸张需多次通过由压印滚筒和成像表面(或中间载体表面)形成的间隙.为此,压印滚筒或类似部件上应带有抓纸机构,保持纸张在固定的位置上.

加入GDDS与提高我国统计数据质量

GDDS是国际货币基金组织出台的数据公布通过系统 ,它为改善成员国统计数据质量提供了一个综合框架。此框架要求我国建立健全与国际接轨的统计指标体系 ,提高统计数据质量水平 ,使统计数据的发布制度化、透明化 ,更好地满足政府对数据“快、精、准”

Maglev self-excited vibration suppression with a virtual sky-hooked damper

This work addresses the problem of self-excited vibration,which degrades the stability of the levitation control,decreases the ride comfort,and restricts the construction cost of maglev system.Firstly,a minimum model containing a flexible bridge and a single levitation unit is presented.Based on the simplified model,the principle underlying the self-excited vibration is explored.After investigations about the energy transmission between the levitation system and bridge,it is concluded that the increment of modal damping can dissipate the accumulated energy by the bridge and the self-excited vibration may be avoided.To enlarge the equivalent modal damping of bridge,the sky-hooked damper is adopted.Furthermore,to avoid the hardware addition of real sky-hooked damper,considering the fact that the electromagnet itself is an excellent actuator that is capable of providing sufficiently fast and large force acting on the bridge to emulate the influence of the real sky-hooked damper,the technique of the virtual sky-hooked damper is proposed.The principle underlying the virtual sky-hooked damper by electromagnet is explored and the vertical velocity of bridge is estimated.Finally,numerical and experimental results illustrating the stability improvement of the vehicle-bridge interaction system are provided.

甚高频空地数据链系统与ARINC618协议

简述了数据链通信的基本概念和功能;介绍了中国民航基于VHF的ACARS数据链系统的构成和工作原理以及典型的ACARS机载设备的组成、数据流程和频率管理;重点解释了ARINC618协议中电报结构和各段的定义。

Multi-Resonant-Activation for a System Only Driven by Multi-State Noise

We consider the escape of the particles multi-state noise. It is shown that, the noise can make over fluctuating potential barrier for a system only driven by a the particles escape over the fluctuating potential barrier in some circumstances; but in other circumstances, it can not. If the noise can make the particle escape over the fluctuating potential barrier, the mean first passage time （MFPT） can display the phenomenon of multi-resonant-activation. For this phenomenon, there are two kinds of resonant activation to appear. One is resonant activation for the MFPTs as the function of the flipping rates of the fluctuating potential barrier; the other is that for the MFPTs as the functions of the transition rates of the multi-state noise.

Usability and Effectiveness of Mobile Learning Course Content Application as a Revision Tool

The use of mobile phone technologies in the education sector is getting more attention nowadays. This is due to the advancement of technologies equipped in majority of the mobile phones which makes the devices become more capable of supporting the learning and teaching activities. Mobile learning （m-learning） is a learning tool which can be run on mobile devices. It can be considered as an enhancement to the electronic learning （e-learning）. M-learning overcomes several limitations of e-learning especially in term of mobility. It provides more independent way of learning whereby learners can use the application to do the learning activities at anytime and any place. However, as with other learning and teaching applications, applications to be developed for mobile learning must also be developed based on certain learning theories and guidelines in order for them to be effective as well as usable. Therefore, in this paper, the development process of a mobile learning course content application called Mobile System Analysis and Design （MOSAD） as a revision tool will be shared and its testing＇s conduct and results will also be presented and discussed. MOSAD was developed with the content of a topic from the System Analysis and Design （SAD） course conducted at Universiti Teknologi PETRONAS （UTP）. A heuristic test involving 5 experts in the area of Human Computer Interaction （HCI） were conducted after the first version of MOSAD was completed to strengthen its functionality and usability, followed by a Post Test Quasi Experimental Design which was conducted to 116 UTP second year students who took the SAD course to test the effectiveness and usability of MOSAD after it was revised. As a result from the post test, the students who had used MOSAD （66 out of the 116 students） as their revision tool for answering ten quiz questions obtained a mean score of 7.7576 as compared to 5.160 obtained by the other group of students （50 out of the 116 students） who used traditional methods of revision. Besides, usability test which tested on consistency, leamability, flexibility, minimal action and minimal memory load of MOSAD gave results above 3.5 for each metric based on the rating of 1 to 5. Thus, both results indicate that MOSAD is effective and usable as a revision tool for the higher education students.

Energy Saving for Automatic Train Control in Moving Block Signaling System

With rapid development of the railway traffic, the moving block signaling system （MBS） method has become more and more important for increasing the track capacity by allowing trains to run in a shorter time-headway while maintaining the required safety margins. In this framework, the tracking target point of the following train is moving forward with its leading train. This paper focuses on the energy saving tracking control of two successive trains in MBS. Nonlinear programming method is used to optimize the energy-saving speed trajectory of the following train. The real-time location of the leading train could be integrated into the optimization process. Due to simplicity, it can be used for online implementation. The feasibility and effectiveness are verified through simulation. The results show that the new method is efficient on energy saving even when disturbances present.

The Effectiveness of the Methane Drainage of the Rock-Mass with a Parallel Ventilation Heading during Longwall Mining

Methane drainage is used in Polish coal mines in order to reduce mine methane emission as well as to keep methane concentration in mine workings at safe levels. This article describes the method of methane drainage used in longwall 2 in seam 506. In Poland, coal seams are frequently mined in difficult conditions of very high methane hazard. Under such situations, methane is drained by means of parallel ventilation headings. This paper shows the influence of a specific ventilation system on the drainage efficiency at longwall 2 in seam 506. At this longwall, measurements of methane emission and the efficiency of drained methane were conducted. They consisted in gauging methane concentration, air velocity, absolute air pressure and the amount of methane removed via a drainage system. Experimental data were used to estimate the variations in absolute methane-bearing capacity, ventilation air methane and most importantly, to gauge the efficiency of methane drainage.

Study on Supply Drive and Demand Drive of the Telecommunication Operation

This paper analyzes the total movement period of the development of the world telecommunication industry, and points out the basic principles of the supply and demand regulation and the market drive are important and useful to the telecommunication industry. The thesis puts forward the pertinent evaluation and the positive suggestions according to the general characteristics and individual characteristics of Chinese telecommunication industry and emphasizes the meaning of the demand drive.

Stochastic prediction and control to methane in coalmine

The ventilation system plays an essential role in underground workings, and improvements in dilution effect to stochastic methane build-up at cul-de-sac of a coalmine require the installation of mixed ventilation system. For 4-12-1 I N02.8A centrifugal ventilation fan, the characteristic operating function of its mixed ventilation system is calculated from ventilation quantity and total pressure in the actual working status. At cul-de-sac of the reference coalmine, the evolution of methane concentration is a compound Poisson process and equivalent to a Brownian motion for Gaussian distributed increments. Solution of stochastic differential equation driven by mixed ventilation system, with dilution equation for its closure, provides parameters of mine ventilation system for keeping methane concentration within the permissible limit at cul-de-sac of the reference coalmine. These results intend to shed some light on application of blowing-sucking mixed ventilation systems in underground workings, and establish stochastic trends to consider methane control in coalmines.

Interoperable Process： Efficient Systems in New Constructive and Product Performances

In the construction sector, which is one of the major goals of the new economy, the company is aiming at a new constructive practice and upgrading of the built, using ICT （information and communications technology） technologies. So the focus is on new operating and organizational models of sustainable building processes in the architecture, engineering and construction sectors, which are based on three-dimensional models of digital technology BIM （building information modeling）. It is intended as a human activity that improves building workflows and, through software and IFACs （industry foundation classes）, manages flexibility, coordinates and optimizes operational choices on time, economic, and environmental sustainability parameters. The goal is a new interoperable building process that involves designers, contractors and businesses from programming to lifecycle building and maintenance through the integrated project delivery of the building. Dynamic architectures, interactive with efficient technological and constructive systems, are integrated with innovative products of complex nature and bi-directional performance, engineered, with energy storage and renewable resources. The methodologies are based, above all, on the adoption of BIM technologies with the digital project manager and the use of robotic technological tools. Digitization is applied for the design and construction of architectural and infrastructure artifacts, in interaction with intelligent, adaptive, nanotechnical and user-friendly materials and climate. The results are aimed at efficient buildings with user comfort and safety, accuracy, and risk monitoring with remote monitoring, highlighting VDC （visual design construction） in CID （computational intelligent design）.

Resurgence relation and global asymptotic analysis of orthogonal polynomials via the Riemann-Hilbert approach

A global asymptotic analysis of orthogonal polynomials via the Riemann-Hilbert approach is presented,with respect to the polynomial degree.The domains of uniformity are described in certain phase variables.A resurgence relation within the sequence of Riemann-Hilbert problems is observed in the procedure of derivation.Global asymptotic approximations are obtained in terms of the Airy function.The system of Hermite polynomials is used as an illustration.

Existence and construction of simultaneous cloning machines for mixed states

It is a well-known fact that the no-cloning theorem forbids the creation of identical copies of an arbitrary unknown quantum state. In other words, there does not exist a quantum cloning machine that can clone all quantum states. However, it is possible to clone given quantum states under certain conditions, for instance, k distinct pure states ｜ψ1〉, ｜ψ2）,....,｜ψk） can be cloned simultaneously if and only if they are orthogonal. This paper discusses the existence and construction of simultaneous cloning machines for mixed states. It is proved that k distinct mixed states Pl,P2 Pk of the n-dimensional quantum system Cn can be cloned simultaneously, that is, there exists a quantum channel Ф on .Mn ⊙ Mn and a state ∑ in Mn, such that Ф（ρi ⊙∑） = ρi ⊙ ρi for all i, if and only if ρiρj = 0 （i ≠j）. Also, the constructing procedure of the desired simultaneous cloning machine is given.