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141.
控制系统中任务的调度不仅影响系统的资源利用率,而且影响系统的控制性能。首先分析了周期性实时任务,并给出了任务模型。基于此,采用了EDF调度算法。根据系统的性能指标与任务的采样周期的关系,采用粒子群算法对系统性能进行优化。仿真结果表明,这种算法是有效的。  相似文献   
142.
We investigated the usefulness of the Over-Claiming Questionnaire (OCQ) as a measure of cognitive abilities. In OCQs respondents are asked to rate their familiarity with items of academic or everyday knowledge (Paulhus, Harms, Bruce, & Lysy, 2003). Some items exist in reality (reals), and others do not (foils). We developed four OCQs, each consisting of 40 reals and 8 foils from the domains of Science, Humanities and Civics. The OCQs were administered in a longitudinal rotation design to 112 participants who attended the 9th school grade at the beginning of the study. In latent variable regression analyses 53% of variation in the reals could be explained by fluid and crystallized intelligence and over-claiming as indicated by responses to foils. Further variation in responses to reals and foils was explained by intellectual engagement. Our results show that self-reported knowledge, although positively related to measures of ability, to a large extent reflects over-claiming.  相似文献   
143.
信息技术影响到外语教与学的方方面面。对学生进行调查后发现,近半数学生喜欢通过网络和手机等电子工具学习英语;有1/3左右的学生喜欢通过虚拟学习环境学习英语;只有很少一部分学生喜欢去自主学习中心学习英语。从学生视角对造成上述现象原因进行分析有助于帮助学生提高学习能力。  相似文献   
144.
分析中国科举文化概念时,不能单纯以文化论文化,而应更多地分析科举制产生的土壤——科举社会,这个科举社会包含着科举人群、科举制度及科举风俗等。科举文化内容可被粗略划分为物质内容与人文意识内容两个部分。科举文化随着科举制及封建社会环境的变化呈现出不同的发展特点,既表现出明显的时代性特征,又表现出与其他封建社会文化相区别的独特特征,如至公性、竞争性、实用性等。  相似文献   
145.
该文根据国家权威档案文献,论述1860年汕头开埠始末的曲折过程;指出,汕头开埠是第二次鸦片战争清政府屈辱妥协外交路线的产物,是中华民族的屈辱史,是粤东门户被迫"开放"史,也是潮汕历史大走向的重要转折点。今人应以胡乔木《国史事典》的题词"在沉重的历史中,汲取奋进的力量"为警示,"知耻近于勇",爆发奋进之力,建设美好家园。  相似文献   
146.
Amorphous InGaZnO (a-IGZO) films were deposited on the corning eagle XG (EXG) glass substrates using magnetron sputtering method. The structure, surface morphology, electrical and optical properties of these films were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), semiconductor parameter analyzer and spectrophotometry, respectively. The influence of oxygen flow on the electrical properties of IGZO thin films was studied, showing that increasing oxygen flow changes the resistivity with six orders of magnitude. The contact resistance of ITO/IGZO is 7.35×10−2 Ω·cm2, which suggests that a good ohmic contact exists between In2O3: Sn (ITO) and IGZO film.  相似文献   
147.
Depth maps are used for synthesis virtual view in free-viewpoint television (FTV) systems.When depth maps are derived using existing depth estimation methods,the depth distortions will cause undesirable artifacts in the synthesized views.To solve this problem,a 3D video quality model base depth maps (D-3DV) for virtual view synthesis and depth map coding in the FTV applications is proposed.First,the relationships between distortions in coded depth map and rendered view are derived.Then,a precisely 3DV quali...  相似文献   
148.
The core of smoothed particle hydrodynamics (SPH) is the nearest neighbor search subroutine. In this paper, a nearest neighbor search algorithm which is based on multiple background grids and support variable smooth length is introduced. Through tested on lid driven cavity flow, it is clear that this method can provide high accuracy. Analysis and experiments have been made on its parallelism, and the results show that this method has better parallelism and with adding processors its accuracy become higher, thus it achieves that efficiency grows in pace with accuracy.  相似文献   
149.
Hilbert-Huang transform method has been widely utilized from its inception because of the superiority in varieties of areas. The Hilbert spectrum thus obtained is able to reflect the distribution of the signal energy in a number of scales accurately. In this paper, a novel feature called ECC is proposed via feature extraction of the Hilbert energy spectrum which describes the distribution of the instantaneous energy. The experimental results conspicuously demonstrate that ECC outperforms the traditional short-term average energy. Combination of the ECC with mel frequency cepstral coefficients (MFCC) delineates the distribution of energy in the time domain and frequency domain, and the features of this group achieve a better recognition effect compared with the feature combination of the short-term average energy, pitch and MFCC. Afterwards, further improvements of ECC are developed. TECC is gained by combining ECC with the teager energy operator, and EFCC is obtained by introducing the instantaneous frequency to the energy. In the experiments, seven status of emotion are selected to be recognized and the highest recognition rate 83.57% is achieved within the classification accuracy of boredom reaching 100%. The numerical results indicate that the proposed features ECC, TECC and EFCC can improve the performance of speech emotion recognition substantially.  相似文献   
150.
Parkinson’s disease (PD) is a heterogenous disease caused by multifactorial etiology. PD is characterized by the loss of dopaminergic (DA) neurons in the substantia nigra and the accumulation of Lewy bodies. In this study, two Drosophila PD models by exposing Drosophila to rotenone (sporadic PD models) are proposed, and the human α-synuclein A30P protein (family PD models) in Drosophila is expressed respectively. Both models recapitulated the main human PD symptoms including the loss of dopaminergic neurons...  相似文献   
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