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91.
精品课程是衡量学校办学水平的重要标志,网站则是课程呈现的重要平台,起着对外交流和展示特色的关键作用,因而网站建设应具有鲜明的特色与亮点。该文从分析网站建设的栏目设置、内容选择和界面设计入手,突出精品课程网站建设需要注意的特色与亮点,便于学习者掌握课程核心要素,从而为培养生产、建设、服务和管理第一线高素质技能型专门人才提供特色教学平台。 相似文献
92.
以单片机为主控器件的HOLTER(动态心电监护仪)系统的实时性和临床诊断的保真度要求都较高,这就要求使用于其上的压缩算法应简单高效且近无损,而目前针对此类设备的压缩算法虽然有较高的压缩率,但失真度和复杂度也较高。本文提出一种针对HOLTER系统的低复杂近无损预测算法,实验表明,该方法在保证一定压缩率的条件下,具有很好的实时性和保真度。 相似文献
93.
The recent evolution of wireless sensor networks have yielded a demand to improve energy-efficient scheduling algorithms and energy-efficient medium access protocols. This paper proposes an energy-efficient real-time scheduling scheme that reduces power consumption and network errors on dual channel networks. The proposed scheme is based on a dynamic modulation scaling scheme which can scale the number of bits per symbol and a switching scheme which can swap the polling schedule between channels. Built on top of EDF scheduling policy, the proposed scheme enhances the power performance without violating the constraints of real-time streams. The simulation results show that the proposed scheme enhances fault-tolerance and reduces power consumption. 相似文献
94.
In order to characterize the non-Gaussian information contained within the EEG signals, a new feature extraction method based on bispectrum is proposed and applied to the classification of right and left motor imagery for developing EEG-based brain-computer interface systems. The experimental results on the Graz BCI data set have shown that based on the proposed features, a LDA classifier, SVM classifier and NN classifier outperform the winner of the BCI 2003 competition on the same data set in terms of either the mutual information, the competition criterion, or misclassification rate. 相似文献
95.
Integrating job parallelism in real-time scheduling theory 总被引:1,自引:0,他引:1
We investigate the global scheduling of sporadic, implicit deadline, real-time task systems on multiprocessor platforms. We provide a task model which integrates job parallelism. We prove that the time-complexity of the feasibility problem of these systems is linear relatively to the number of (sporadic) tasks for a fixed number of processors. We propose a scheduling algorithm theoretically optimal (i.e., preemptions and migrations neglected). Moreover, we provide an exact feasibility utilization bound. Lastly, we propose a technique to limit the number of migrations and preemptions. 相似文献
96.
Bo Li Author Vitae Chun-Hou Zheng Author Vitae Author Vitae 《Pattern recognition》2008,41(12):3813-3821
In this paper an efficient feature extraction method named as locally linear discriminant embedding (LLDE) is proposed for face recognition. It is well known that a point can be linearly reconstructed by its neighbors and the reconstruction weights are under the sum-to-one constraint in the classical locally linear embedding (LLE). So the constrained weights obey an important symmetry: for any particular data point, they are invariant to rotations, rescalings and translations. The latter two are introduced to the proposed method to strengthen the classification ability of the original LLE. The data with different class labels are translated by the corresponding vectors and those belonging to the same class are translated by the same vector. In order to cluster the data with the same label closer, they are also rescaled to some extent. So after translation and rescaling, the discriminability of the data will be improved significantly. The proposed method is compared with some related feature extraction methods such as maximum margin criterion (MMC), as well as other supervised manifold learning-based approaches, for example ensemble unified LLE and linear discriminant analysis (En-ULLELDA), locally linear discriminant analysis (LLDA). Experimental results on Yale and CMU PIE face databases convince us that the proposed method provides a better representation of the class information and obtains much higher recognition accuracies. 相似文献
97.
We present an approach for extracting extremal feature lines of scalar indicators on surface meshes, based on discrete Morse Theory. By computing initial Morse‐Smale complexes of the scalar indicators of the mesh, we obtain a candidate set of extremal feature lines of the surface. A hierarchy of Morse‐Smale complexes is computed by prioritizing feature lines according to a novel criterion and applying a cancellation procedure that allows us to select the most significant lines. Given the scalar indicators on the vertices of the mesh, the presented feature line extraction scheme is interpolation free and needs no derivative estimates. The technique is insensitive to noise and depends only on one parameter: the feature significance. We use the technique to extract surface features yielding impressive, non photorealistic images. 相似文献
98.
Abstract. We consider two fundamental problems in dynamic scheduling: scheduling to meet deadlines in a preemptive multiprocessor setting,
and scheduling to provide good response time in a number of scheduling environments. When viewed from the perspective of traditional
worst-case analysis, no good on-line algorithms exist for these problems, and for some variants no good off-line algorithms
exist unless P = NP .
We study these problems using a relaxed notion of competitive analysis, introduced by Kalyanasundaram and Pruhs, in which
the on-line algorithm is allowed more resources than the optimal off-line algorithm to which it is compared. Using this approach,
we establish that several well-known on-line algorithms, that have poor performance from an absolute worst-case perspective,
are optimal for the problems in question when allowed moderately more resources. For optimization of average flow time, these
are the first results of any sort, for any NP -hard version of the problem, that indicate that it might be possible to design good approximation algorithms. 相似文献
99.
Yi?GongEmail author Wei?Chen Long?Zhang Yun?Zeng Qunsheng?Peng 《The Visual computer》2008,24(2):95-103
In this paper we introduce an approximate image-space approach for real-time rendering of deformable translucent models by
flattening the geometry and lighting information of objects into textures to calculate multi-scattering in texture spaces.
We decompose the process into two stages, called the gathering and scattering corresponding to the computations for incident and exident irradiance respectively. We derive a simplified illumination model
for the gathering of the incident irradiance, which is amenable for deformable models using two auxiliary textures. In the scattering stage,
we adopt two modes for efficient accomplishment of the view-dependent scattering. Our approach is implemented by fully exploiting the capabilities of graphics processing units (GPUs). It achieves visually
plausible results and real-time frame rates for deformable models on commodity desktop PCs. 相似文献
100.
Barbara Yersin Jonathan Maïm Fiorenzo Morini Daniel Thalmann 《The Visual computer》2008,24(10):859-870
Real-time crowd motion planning requires fast, realistic methods for path planning as well as obstacle avoidance. In a previous
work (Morini et al. in Cyberworlds International Conference, pp. 144–151, 2007), we introduced a hybrid architecture to handle real-time motion planning of thousands of pedestrians. In this article, we
present an extended version of our architecture, introducing two new features: an improved short-term collision avoidance
algorithm, and simple efficient group behavior for crowds. Our approach allows the use of several motion planning algorithms
of different precision for regions of varied interest. Pedestrian motion continuity is ensured when switching between such
algorithms. To assess our architecture, several performance tests have been conducted, as well as a subjective test demonstrating
the impact of using groups. Our results show that the architecture can plan motion in real time for several thousands of characters.
相似文献
Daniel ThalmannEmail: |