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.     

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。     

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.     

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.     

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。     

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.     

试论如何加强国有土地资产管理

我国的土地使用制度改革历经十余年,取得了显著的经济效益和社会效益,使国有土地资产的管理工作逐步走向完善,但仍存在以下问题：①违法批地、违法占地现象。②在增量土地剧增、耕地锐减的同时,存量土地却大量闲置或利用效率低下,造成国有土地资产的极大浪费。③土地隐形市场大量存在。④国有土地资产大量流失。针对土地管理工作中存在的这些问题,笔者提出了加强国有土地资产管理的对策建议：①将划拨土地的审批权限集中,统一由省和国家审批,取消市、县对划拨土地的审批权。②降低土地出让金和土地收益金上缴上级财政的比例,以提高当地土地管理部门及当地政府收取国有土地使用权有偿使用收入的积极性。③制定有效措施,鼓励利用存量土地。④建立土地使用证“年检”制度。⑤加强土地法制建设,加大土地执法监察力度。⑥采用现代化管理手段。     

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．     

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.     

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.     

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。     

Buffer management in real-time active database systems

Real-time active database systems (RTADB) have attracted the attention of researchers in recent times. Such systems are envisioned as control systems for environments as diverse as process control, network management and automated financial trading. Sensors distributed throughout the system report the state of the system to the database. Unacceptable state reports typically results in corrective actions being triggered with deadlines. Thus RTADB's incorporate both real-time as well as active characteristics. We study buffer management in RTADB. Buffer management is recognized as not being a well studied area in real-time systems. As a result of our work, we postulate PAPER, a new buffer management scheme that relies on two strategies: prefetching and priority based buffer replacement. We report the result of studies of the performance of PAPER, as compared to that of existing buffer management algorithms. The insights derived from this paper impact both real-time database systems as well as real-time, active database systems     

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.     

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.     

A dynamic data dissemination mechanism for Cassandra NoSQL data store

The Journal of Supercomputing - Cassandra as a type of NoSQL databases has been put forward so as to surmount the hurdles of traditional relational databases in the scope of big data as well as...     

An attempt to design qualitative differential games†

Obviously enough, a differential game as an extension of a control system, as well as many other systems of dynamics, may be synthesized. In case of qualitative games this may lead to certain classes of differential systems of the game or certain classes of strategies, implying a prescribed outcome in the form of a prescribed qualitative property of the game path. The synthesis procedure may serve as a tool for solving games, as well as the game-methods may help in the synthesis; the proper relation, however, has to be defined.     

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.     

组合电路随机测试的一种新方法

本文在随机测试的基础上提出了逆随机测试（ART）的新概念，在该测试序列的集合中各测试码之间的海明距离为尽可能的大，这样可以使不同的测试码检测到更多不同的故障，从则提高了测试效率和故障覆盖率。本文给出了构造逆随机测试序列（ARTS）的详细过程，并且严格证明了该序列的高效和正确性，同时还给出了用Benchmark和其它电路作为例子的实验结果。     

Wearable computing: toward humanistic intelligence

Over the past 20 years, wearable computing has emerged as the perfect tool for embodying humanistic intelligence (HI). HI is intelligence that arises when a human is part of the feedback loop of a computational process in which the human and computer are inextricably intertwined. It is common in the field of human-computer interaction to think of the human and computer as separate entities. (indeed, the term "HCI" emphasizes this separateness by treating the human and computer as different entities that interact.) However, in HI theory, we prefer not to think of the wearer and the computer with its associated I/O apparatus as separate entities. Instead, we regard the computer as a second brain and its sensory modalities as additional senses, in which synthetic synesthesia merges with the wearer's senses. When a wearable computer functions in a successful embodiment of HI, the computer uses the human's mind and body as one of its peripherals, just as the human uses the computer as a peripheral. This reciprocal relationship is at the heart of HI.     

Modelling of stationary and growing cracks in FE framework without remeshing: a state-of-the-art review

The recently developed techniques for modelling cracking within the finite element (FE) framework which use meshes independent of the crack configuration and thus avoid remeshing are reviewed. They combine the traditional FE method with the partition of unity method for modelling individual cracks, intersecting or branching cracks, as well as cracks emanating from holes or other internal interfaces. Numerical integration for the enriched elements, linear dependence and the corresponding solution techniques for the discretized system of equations, as well as the accuracy of the crack tip fields are addressed. Future improvements of the techniques as well as their applications are discussed.