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91.
针对当前军校大学计算机基础课程立足于以建设信息化军队,打赢信息化战争的根本方针,结合自身的教学经验,注重在教学实施上以实战化案例教学为原则,形成问题前导、主题研讨、案例辨析、推演论证四位一体的案例化教学方法。列出了大学计算机基础课程中的所有知识模块及教学目标,并详细分析几个关键模块的教学步骤,为军校大学计算机基础课程教学提供一些方法和思路。  相似文献   
92.
In recent years, cubic regularization algorithms for unconstrained optimization have been defined as alternatives to trust-region and line search schemes. These regularization techniques are based on the strategy of computing an (approximate) global minimizer of a cubic overestimator of the objective function. In this work we focus on the adaptive regularization algorithm using cubics (ARC) proposed in Cartis et al. [Adaptive cubic regularisation methods for unconstrained optimization. Part I: motivation, convergence and numerical results, Mathematical Programming A 127 (2011), pp. 245–295]. Our purpose is to design a modified version of ARC in order to improve the computational efficiency preserving global convergence properties. The basic idea is to suitably combine a Goldstein-type line search and a nonmonotone accepting criterion with the aim of advantageously exploiting the possible good descent properties of the trial step computed as (approximate) minimizer of the cubic model. Global convergence properties of the proposed nonmonotone ARC algorithm are proved. Numerical experiments are performed and the obtained results clearly show satisfactory performance of the new algorithm when compared to the basic ARC algorithm.  相似文献   
93.
一种抗独立攻击的WSN三维安全定位算法   总被引:1,自引:0,他引:1  
陈宜  蒋朝惠  郭春 《传感技术学报》2015,28(11):1702-1707
为解决无线传感器网络中节点定位缺乏安全性和定位精度不高的问题,基于最速下降法与牛顿迭代法提出了一种新的三维安全定位算法。该算法首先给出三维空间下未知节点定位的计算方法和独立攻击模型,然后利用最速下降法和恶意锚节点检测技术选出最优锚节点数据,并结合牛顿迭代法实现了快速高精度的三维安全定位。实验结果表明,在危险的环境下,该算法能有效抵抗独立攻击以及在定位精度和未知节点可成功定位率方面都具有较好的优势。  相似文献   
94.
21世纪是一个信息化的知识经济时代,以计算机为代表的现代信息技术的开发利用,使图书馆发生了巨大的变革。青年馆员作为图书馆行业的新生力量,为图书馆带来了生机与活力。作为满足读者需求的重要保证,新时代的图书馆员既要拥有熟练应用图书馆相关信息技术的能力,还要拥有复合型知识结构。  相似文献   
95.
Soil organic matter dynamics are essential for terrestrial ecosystem functions as they affect biogeochemical cycles and, thus, the provision of plant nutrients or the release of greenhouse gases to the atmosphere. Most of the involved processes are driven by microorganisms. To investigate and understand these processes, individual-based models allow analyzing complex microbial systems' behavior based on rules and conditions for individual entities within these systems, taking into account local interactions and individual variations. Here, we present a streamlined, user-friendly and open version of the individual-based model INDISIM-SOM, which describes the mineralization of soil carbon and nitrogen. It was implemented in NetLogo, a widely used and easily accessible software platform especially designed for individual-based simulation models. Including powerful means to observe the model behavior and a standardized documentation, this increases INDISIM-SOM's range of potential uses and users, and facilitates the exchange among soil scientists as well as between different modeling approaches.  相似文献   
96.
Curvature-based surface energies are frequently used in mathematics, physics, thin plate and shell engineering, and membrane chemistry and biology studies. Invariance under rotations and shifts makes curvature-based energies very attractive for modeling various phenomena. In computer-aided geometric design, the Willmore surfaces and the so-called minimum variation surfaces (MVS) are widely used for shape modeling purposes. The Willmore surfaces are invariant w.r.t conformal transformations (Mbius or conformal invariance), and studied thoroughly in differential geometry and related disciplines. In contrast, the minimum variation surfaces are not conformal invariant. In this paper, we suggest a simple modification of the minimum variation energy and demonstrate that the resulting modified MVS enjoy Mbius invariance (so we call them conformal-invariant MVS or, shortly, CI-MVS). We also study connections of CI-MVS with the cyclides of Dupin. In addition, we consider several other conformal-invariant curve and surface energies involving curvatures and curvature derivatives. In particular, we show how filtering with a conformal-invariant curve energy can be used for detecting salient subsets of the principal curvature extremum curves used by Hosaka and co-workers for shape quality inspection purposes.  相似文献   
97.
长期以来,宁夏司法警官职业学院各种信息通过Office软件来存储,处理,在信息的更新,共享,查询,版本控制上等方面存在很多问题,管理这些信息比较繁琐,并且信息很难共享,因此学院急需一套信息管理系统来管理这些信息。该文对宁夏司法警官职业学院学生信息管理系统的项目立项、用户需求征询、设计开发、测试实施做了一个比较全面的概述。  相似文献   
98.
In this article, new probabilistic health-informatics indices connecting probabilities: Pr(A),Pr(B),Pr(A IB) and P r(A ]B-) are discovered, where .4 and B denote respectively the "ability of a hospital to treat anthrax patients" and "whether a hospital drilled to be prepared to deal with an adverse bioterrorism". These probabilistic informatics are not seen in any textbooks or journal articles and yet, they are too valuable to be unnoticed to comprehend the hospitals' preparedness to treat anthrax patients in an outbreak of bioterrorism. A demonstration of this new probabilistic informatics is made in this article with the data in the U.S. Government's General Accounting Office's report GA0-03-924. Via this example, this article advocates the importance of the above mentioned probabilistic-informatics for health professionals to understand and act swiftly to deal with public health emergencies.  相似文献   
99.
Artificial bee colony (ABC) algorithm is a relatively new optimization technique which has been shown to be competitive to other population-based algorithms. However, there is still an insufficiency in ABC regarding its solution search equation, which is good at exploration but poor at exploitation. To address this concerning issue, we first propose a modified search equation which is applied to generate a candidate solution in the onlookers phase to improve the search ability of ABC. Further, we use the Powell's method as a local search tool to enhance the exploitation of the algorithm. The new algorithm is tested on 22 unconstrained benchmark functions and 13 constrained benchmark functions, and are compared with some other ABCs and several state-of-the-art algorithms. The comparisons show that the proposed algorithm offers the highest solution quality, fastest global convergence, and strongest robustness among all the contenders on almost all test functions.  相似文献   
100.
在水利工程混凝土施工中,施工单位经常用到混凝土输送泵。而在施工当中,往往输送泵用什么型号、功率为多大比较经济适用是每个施工单位必须考虑的事情。文中根据在哈达山水利枢纽输水工程施工中的经验,简要介绍混凝土输送泵的型号,论述了其主要参数及电动机功率的选择方法。  相似文献   
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