矿井宽带无线传输技术研究

提出了矿井宽带无线传输技术是解决采掘工作面移动监控、监视和语音通信需求的关键技术。提出了矿井宽带无线传输应满足传输带宽宽、便于接入有线宽带网络、中继设备少、体积小、发射功率小、电磁兼容性好、安全性好、传输协议标准化、电源电压波动适应能力强等要求。提出了漏泄通信不能用作矿井宽带无线传输技术,但可用于煤矿井下局部通信等;感应通信不能用作矿井宽带无线传输技术,但可用于煤矿井下救灾通信等;透地通信不能用作矿井宽带无线传输技术,但可用于煤矿井下避难硐室等应急通信;小灵通、CDMA、GSM、Bluetooth不能用作矿井宽带无线传输技术;RFID不能用作矿井宽带无线传输技术,但可用于煤矿物联网、矿用设备管理和防碰撞等;ZigBee不能用作矿井宽带无线传输技术,但可用于煤矿井下人员、胶轮车、电机车等动目标精确定位和矿用传感器无线传输等;UWB不能用作矿井宽带无线传输技术,但可用于煤矿井下生命探测、防碰撞、煤矿井下人员和胶轮车等动目标精确定位等;WCDMA、CDMA2000、TD-SCDMA等3G不能用作矿井宽带无线传输技术,但可用于煤矿井下语音移动通信等。提出了矿井宽带无线传输技术宜采用WiFi,4G有可能成为未来矿井宽带无线传输技术。     

神华集团数字矿山建设研究

探讨了数字矿山的内涵及特征、神华集团建设数字矿山的意义及目标,得出结论:数字矿山以面向矿山业务为依托,以数据互联互通为原则,以信息的整合、利用为核心,以矿山生产过程自动化为基础,以统一的传输网络平台为框架,以统一的软件平台为手段,以绿色开采技术、装备技术、信息技术为支撑,以标准体系为保障,其建设目标为"安全、绿色、智能、高效"。     

Linux进程调度算法分析

在Linux系统中,进程作为实体自始至终运行在系统之中,进程使用系统的资源,而进程的调度更是影响系统的性能:进程响应时间尽可能快,后台进程的吞吐量尽可能高,进程"饿死"现象尽可能避免,低优先级和高优先级进程需要尽可能调和.本文从Linux 2.4.0内核角度分析影响进程调度的各个因素和调度处理流程,以及在SMP(Symmetric Multi Processing)的进程调度处理.     

An analysis of two-parent recombinations for real-valued chromosomes in an infinite population

This paper concerns recombinations which produce offspring from two parents. We assume an infinite population and regard recombinations as transformations of stochastic variables represented as chromosomes. We then formalize recombinations with the probability density functions of stochastic variables represented as the parameters and describe the change of the probability density functions of chromosomes before and after recombination. Our formalization includes various proposed recombinations, such as multi-point, uniform, and linear crossover, as well as BLX-alpha. We also derive certain properties of the operators, such as diversification and decorrelation.     

网络拓扑自动发现系统设计与实现

摘要：设计基于SNMP和其它协议的网络拓扑发现算法,实现三层交换机和路由器为网关的网络拓扑的快速发现,尽可能地发现完整的网络,且对网络带来的额外负栽和开销尽可能小。     

The efieldbook program: A teaching resource for geology

The eFieldBook program is a geology teaching tool with high didactic potential that guides a student’s work in the field using multimedia and other resources. This program allows the collection of geo-referenced geological information as well as its storage and transmission, if necessary, as soon as it is collected. The data can be collected as in traditional field notebooks or on maps and photographs. The information can be used as soon as it is collected and can be exported to other programs such as Word, Excel, Georient or statistical packages. eFieldBook safely stores and backs up user information by sending any data collected to a selected Internet target at regular time intervals.     

Planar split dual gate MOSFET

A new planar split dual gate （PSDG） MOSFET device, its characteristics and experimental results, as well as the three dimensional device simulations, are reported here for the first time. Both theoretical calculation and 3D simulation, as well as the experiment data, show that the two independent split dual gates can provide dynamical control of the device characteristics, such as threshold voltage （Vt） and sub-threshold swing （SS）, as well as the device saturated current. The PSDG MOSFET transistor leakage current （loft） can be reduced as much as 78% of the traditional single gate MOSFET. The PSDG is fabricated and fully compatible with our conventional 0.18 μm logic process flow.     

Negation as inconsistency. I

The notion of negation as inconsistency is motivated and introduced into PROLOG. This negation is fully compatible with classical negation and gives a version of PROLOG which is a stronger fragment of classical logic than ordinary PROLOG. It is intended that negation as inconsistency replace the notion of negation as failure. Negation as inconsistency can be generalized in a natural way and in its generalized form will include negation as failure as a special case.     

Simultaneous External and Internal Stabilization for Continuous and Discrete-Time Critically Unstable Linear Systems with Saturating Actuators

The issues arising in hybrid or simultaneous external as well as internal stabilization of linear systems with saturating actuators are considered. Four different stabilization problems are studied. Roughly, these problems are (1) simultaneous semi-global external as well as semi-global internal stabilization, (2) simultaneous semi-global external as well as global internal stabilization, (3) simultaneous global external as well as semi-global internal stabilization, and (4) simultaneous global external as well as global internal stabilization. As evident from the literature, the requirement of internal stabilization alone either in the global or semi-global sense demands that the linear part of the given system be (a) stabilizable, and (b) has all its poles in the closed left half complex plane for continuous-time systems while it has all its poles inside and/or on the unit circle for discrete-time systems. This implies that the posed simultaneous stabilization problems are solvable at best only under the conditions (a) and (b). Under such conditions, we construct here explicit state as well as measurement feedback controllers for all the four problems in the case of continuous-time systems, and for the problems (1), (2) and (4) in the case of discrete-time systems. The design methodologies used to construct appropriate feedback laws are based on by now familiar low-gain and low-and-high gain design concepts or certain scheduled versions of them.     

融入Universum学习的度量学习算法

度量学习通过更真实的刻画样本之间的距离,来提高分类和聚类的精度。GMML（Geometric Mean Metric Learning）在学习度量矩阵[A]时,使得在该度量下同类点之间的距离尽可能小,不同类点之间的距离尽可能大。GMML用来学习的训练样本均为目标类数据,而对于现实存在的为数众多的同领域非目标类数据,即Universum数据并未加以利用,不免造成信息的浪费,针对此,提出一种新的度量学习算法--融入Universum学习的GMML（U-GMML）。U-GMML期望得到一个新的度量矩阵[A],使得同类点之间的距离尽可能小,不同类点之间的距离尽可能大,且Universum数据与目标类数据的距离尽可能大,从而使得所学习的度量矩阵[A]更有利于分类。真实数据集上的实验结果验证了该算法的有效性。     

Parallel force measurement with a polymeric microbeam array using an optical microscope and micromanipulator

An image analysis method and its validation are presented for tracking the displacements of parallel mechanical force sensors. Force is measured using a combination of beam theory, optical microscopy, and image analysis. The primary instrument is a calibrated polymeric microbeam array mounted on a micromanipulator with the intended purpose of measuring traction forces on cell cultures or cell arrays. One application is the testing of hypotheses involving cellular mechanotransduction mechanisms. An Otsu-based image analysis code calculates displacement and force on cellular or other soft structures by using edge detection and image subtraction on digitally captured optical microscopy images. Forces as small as 250+/-50 nN and as great as 25+/-2.5 microN may be applied and measured upon as few as one or as many as hundreds of structures in parallel. A validation of the method is provided by comparing results from a rigid glass surface and a compliant polymeric surface.     

计划体系在ERP系统中的作用分析

该文介绍了计划体系在ERP系统中地位、作用以及计划体系在ERP系统设计实施过程中常遇缺陷对常遇问题进行了分析,并提出解决方案。阐述了计划体系在ERP的核心地位,以及MPS,MRP核心计划在整个计划体系的作用以及运作模式,最后总结了ERP实施过程中的难点提出了几点解决方案。     

Crystallographic autostereograms.

Perspective drawings of crystal structures can be presented as autostereograms (or single-image stereograms), and their performance for in-depth perception is similar or even more advantageous than of stereopairs. The autostereograms offer a convenient means for realistic insight into crystal structures without excessive size reduction of their drawings, as required when preparing stereopairs; thus structures either as simple as elements or as complex as proteins can be illustrated in enhanced resolution. The mathematical background and guidelines for preparing crystallographic autostereograms are described.     

IDENTIFICATION OF AN OPEN SYSTEM BY ITS RESOURCES

The open thermodynamic system has been identified as an imprecise dynamical observer and as a rotator, each one with a heuristic function of behavior. These two identification models have been obtained by isolation of the open system. They have been determined as patterns with interpretation of the internalized plan and of the oscillations in the open system. The imprecise dynamical observer has been constructed by perceiving the internalized plan as a fuzzy controller of the speed of a mobile robot, by structuring the internalized plan as a dynamical observer and interpreting the internalized plan as a heuristic function for the remaining path to a goal. The rotator has been constructed by perceiving the oscillations as movement along a cycle, by structuring the oscillations as an autoregressive model and by interpreting the oscillations as a heuristic function for the remaining energy to a goal.     

基于传感器最优配置的等价空间故障检测方法

提出一种基于传感器最优配置的等价空间故障检测方法．针对线性时不变动态系统,给出了传感器最优配置问题的描述,以及基于传感器最优配置的故障检测多目标优化问题的描述．在系统可供测量的N个变量中,选择能获得关于系统故障尽可能多信息的m个变量作为测量变量,在满足对故障具有尽可能高的灵敏度,同时对扰动等未知信号具有尽可能强的鲁棒性的条件下,使整个系统测量成本达到最低．仿真算例说明了所提出设计方法及算法的有效性．     

Modified subset sum heuristics for bin packing

We analyze the worst-case ratio of natural variations of the so-called subset sum heuristic for the bin packing problem, which proceeds by filling one bin at a time, each as much as possible. Namely, we consider the variation in which the largest remaining item is packed in the current bin, and then the remaining capacity is filled as much as possible, as well as the variation in which all items larger than half the capacity are first packed in separate bins, and then the remaining capacity is filled as much as possible. For both variants, we show a nontrivial upper bound of 13/9 on the worst-case ratio, also discussing lower bounds on this ratio.     

Assembly and manipulation of micro devices—A state of the art survey

This paper provides a comprehensive review of research efforts in the emerging field of micro devices assembly (MDA) as well as identifies future directions for research. The general domain dealing with both manual and automated assembly of micro devices can be referred to as MDA. The study of computer-based methods to accomplish the assembly of micron-sized parts can be described as Automated MDA (AMDA). The primary focus of this paper is to provide an overview of concepts related to MDA as well as a review of various segments of MDA research including study of the role of interactive forces at the micro level, the design of innovative gripping and assembly techniques as well as the use of information technology (IT) based approaches.     

Parallel programming in computational science: an introductory practical training course for computer science undergraduates at Aachen University

Parallel programming of high-performance computers has emerged as a key technology for the numerical solution of large-scale problems arising in computational science and engineering (CSE). The authors believe that principles and techniques of parallel programming are among the essential ingredients of any CSE as well as computer science curriculum. Today, opinions on the role and importance of parallel programming are diverse. Rather than seeing it as a marginal beneficial skill optionally taught at the graduate level, we understand parallel programming as crucial basic skill that should be taught as an integral part of the undergraduate computer science curriculum. A practical training course developed for computer science undergraduates at Aachen University is described. Its goal is to introduce young computer science students to different parallel programming paradigms for shared and distributed memory computers as well as to give a first exposition to the field of computational science by simple, yet carefully chosen sample problems.     

基于射频识别技术的智能信箱系统设计

针对传统信箱开锁上锁费时、钥匙遗失时须重新换锁、无指示功能等缺点,以C8051F020为核心,利用射频识别技术设计了具有指示灯、电子锁、键盘、液晶显示等功能的智能信箱系统,实现了信箱的多功能化、智能化、人性化。     

An information theory consideration of a design of test input signals†

A problem of determining optimal periodic test input signals for estimating weighting functions of continuous-time systems is considered by an information theory approach. Under appropriate assumptions, the amount of information provided by the measurements in a period is calculated in terms of the corresponding periodic test input signals. By taking the amount of information as a criterion function, the existence of optimal test input signals and the condition for optimality are studied under energy constraint. It is shown that, in the case of observing sampled outputs, an input signal of as small auto-correlation as possible and, at the same time, of as largo energy as possible is optimal, while, in the case of observing outputs continuously, an input signal of as flat a spectrum as possible and, at the same time, of as large energy as possible is optimal. As an example, the optimality of an M-sequence signal is examined.