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81.
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
82.
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 (Mbius 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 Mbius 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
83.
索荣华 《数字社区&智能家居》2013,(11):7013-7016
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
84.
《国际互联网参考资料服务季刊》2013,18(2):11-20
Abstract The Information Services Department at the Washington, DC law firm, Dickstein Shapiro Morin & Oshinsky, decided in 1995 to provide firmwide access to the Internet. Two separate World Wide Web home pages would be created to meet the divergent needs of the Marketing Department and the information resource requirements of the attorneys, who would be using the Internet for research. In the course of developing Internet pages for the firm, the Library began working in conjunction with attorneys in various practice sections to locate and create Internet resources. The cooperation between attorneys and the Libraiy has led to Internet pages of hypertext linked resources for each specific practice section within the firm. Furthermore, some of the pages of resources have evolved into home pages for the various sections. 相似文献
85.
Ramalingam Shanmugam 《通讯和计算机》2013,(6):743-747
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
86.
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
87.
Basil Mohammed Al-Hadithi Antonio Javier Barragán José Manuel Andújar Agustín Jiménez 《Applied Soft Computing》2013,13(12):4802-4812
In this paper, a fuzzy based Variable Structure Control (VSC) with guaranteed stability is presented. The main objective is to obtain an improved performance of highly non-linear unstable systems. The main contribution of this work is that, firstly, new functions for chattering reduction and error convergence without sacrificing invariant properties are proposed, which is considered the main drawback of the VSC control. Secondly, the global stability of the controlled system is guaranteed.The well known weighting parameters approach, is used in this paper to optimize local and global approximation and modeling capability of T-S fuzzy model.A one link robot is chosen as a nonlinear unstable system to evaluate the robustness, effectiveness and remarkable performance of optimization approach and the high accuracy obtained in approximating nonlinear systems in comparison with the original T-S model. Simulation results indicate the potential and generality of the algorithm. The application of the proposed FLC-VSC shows that both alleviation of chattering and robust performance are achieved with the proposed FLC-VSC controller. The effectiveness of the proposed controller is proven infront of disturbances and noise effects. 相似文献
88.
89.
基于数学形态学边缘检测的车牌字符分割算法 总被引:1,自引:0,他引:1
汽车牌照字符分割是车牌识别过程中的关键步骤,直接影响到字符识别的效果。传统的方法对车牌图像质量要求较高,且抗干扰能力较差。提出一种基于Renyi熵和数学形态学边缘检测的车牌字符投影分割算法,首先用二维Renyi熵最大阈值法对车牌图像做二值化处理,然后用形态学腐蚀运算进行边缘检测,再去除车牌边框,最后通过投影分割提取车牌字符。仿真实验表明,基于Renyi熵最大阈值法和数学形态学边缘检测车牌图像预处理使得车牌字符边缘清晰,降低了噪声的干扰,有利于进行字符投影分割。该算法分割速度快,鲁棒性好,可获得比传统方法更好的分割效果。 相似文献
90.
针对民族地区高等院校计算机教育的特点与面临的困难,提出相应的解决对策和改革方向。探讨如何构建现代人才素质需求与地方民族特色相结合的计算机教学体系,从而促进民族地区计算机人才的培养。 相似文献