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81.
In this paper we present a comparative evaluation of four popular interactive segmentation algorithms. The evaluation was carried out as a series of user-experiments, in which participants were tasked with extracting 100 objects from a common dataset: 25 with each algorithm, constrained within a time limit of 2 min for each object. To facilitate the experiments, a “scribble-driven” segmentation tool was developed to enable interactive image segmentation by simply marking areas of foreground and background with the mouse. As the participants refined and improved their respective segmentations, the corresponding updated segmentation mask was stored along with the elapsed time. We then collected and evaluated each recorded mask against a manually segmented ground truth, thus allowing us to gauge segmentation accuracy over time. Two benchmarks were used for the evaluation: the well-known Jaccard index for measuring object accuracy, and a new fuzzy metric, proposed in this paper, designed for measuring boundary accuracy. Analysis of the experimental results demonstrates the effectiveness of the suggested measures and provides valuable insights into the performance and characteristics of the evaluated algorithms.  相似文献   
82.
针对高度动态、不可预测的海洋环境,开展了无人艇智能运动控制系统的设计研究.首先本文利用认知学科的"图式"概念来分析人体运动控制系统的结构,提出一种混合式分层递阶结构,把人类的先验知识、专家经验融入到该结构中,并在实践中不断学习和完善,则形成了一种混合仿人智能图式;然后根据该图式的思想,设计了自主驾控系统的体系结构,并编制成简单实用、逻辑性强、能实时运行的控制流程;最后进行了无人艇的航线跟踪和安全自主航行的半实物仿真试验,仿真结果表明该无人艇可以安全的避开其他船舶并尽量跟踪航线.  相似文献   
83.
基于项目开发教学法的Visual Basic程序设计教学模式的研究   总被引:1,自引:0,他引:1  
张春英  刘凤春 《计算机教育》2010,(5):105-107,120
本文针对VisualBasic程序设计课程的教学,首先介绍采用项目开发教学法进行教学设计,调整教学顺序,贯彻"问题引导、项目驱动、实训为主、讲练结合、(理论)够用为度"的原则。其次,再探讨强化实战训练,淡化验证型实验,加强设计型实验,以使学生在实践项目训练中掌握程序设计的基本方法,熟悉软件开发的基本流程,增强分析问题解决问题能力,培养创新实践能力,教学效果良好。  相似文献   
84.
信息安全开放实验探讨   总被引:2,自引:1,他引:1  
信息安全专业对实践教学要求很高,需要着力培养学生的实际动手和实践创新能力,由于课时的限制,传统的配合课堂教学的实验课程已经不能满足需求。本文结合南开大学信息安全专业的教学实际,探讨了旨在开发学生创新学习潜能的信息安全开放实验的设计与管理问题,包括信息安全开放实验的目标、内容设计和组织与管理等内容。  相似文献   
85.
In this article, an empirical analysis of experimental design approaches in simulation-based metamodelling of manufacturing systems with genetic programming (GP) is presented. An advantage of using GP is that prior assumptions on the structure of the metamodels are not required. On the other hand, having an unknown structure necessitates an analysis of the experimental design techniques used to sample the problem domain and capture its characteristics. Therefore, the study presents an empirical analysis of experimental design methods while developing GP metamodels to predict throughput rates in a common industrial system, serial production lines. The objective is to identify a robust sampling approach suitable for GP in simulation-based metamodelling. Experiments on different sizes of production lines are presented to demonstrate the effects of the experimental designs on the complexity and quality of approximations as well as their variance. The analysis showed that GP delivered system-wide metamodels with good predictive characteristics even with the limited sample data.  相似文献   
86.
87.
Recent developments in the area of decentralized and infrastructureless systems opened avenues for novel applications. Along with these new technologies, new questions regarding their operational bounds in terms of e.g. scalability and security arose. Due to the sparse presence of real-world decentralized and infrastructureless systems, new protocols and applications have to be scrutinized by means of simulation, in (small-scale) testbeds, and by analytical models. In this paper, we discuss challenges of evaluating security mechanisms for mobile ad hoc networks and peer-to-peer systems. We focus on harmonizing predictions of analytical models and results obtained from simulation studies and testbed experiments.  相似文献   
88.
本文介绍了一种基于工业控制计算机的驾驶员控制单元 (PCU)基本特性检测系统。分别介绍了该系统的总体结构 ,力传感器的选用、A/D采样电路的设计、控制器的设计 ,并给出了各部分的框图、电路原理图以及总体软件控制测试的流程图。该系统研究的方法可用于飞控系统PCU基本特性的检测设计 ,如改变被控对象 ,只需选用相应的传感器和控制器 ,即可实现该被控对象的检测目的。  相似文献   
89.
The paper provides the results of preliminary research on the application of evolutionary computation to integrated structural design in which a complex design support tool automatically conducts both conceptual and detailed design. In the paper, a brief overview of the state of the art in evolutionary computation and its applications to structural design is provided. Next, Inventor 2000 is described, a unique research and structural design tool developed by the authors at George Mason University that combines an evolutionary computation component with a system for wind forces analysis, and a system for the analysis, design and optimisation of steel structures. The paper also presents the results of four structural design experiments conducted with Inventor 2000. The objective of experiments was to investigate various forms of evolutionary computation as applied to structure design. Finally, the paper provides the initial research conclusions and recommendations for further research.  相似文献   
90.
A multicellular organism is shown to be a community of special self-regulated cells with rigid and flexible regulating links, and a long-term adaptive trend of its system reaction to environmental changes is due to changes in the consumer gradients of groups of cells functioning against the imbalance between synthesis and decay of microstructures. __________ Translated from Kibernetika i Sistemnyi Analiz, No. 1, pp. 136–147, January–February 2008.  相似文献   
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