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141.
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
142.
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
143.
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
144.
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
145.
Mobile devices are increasingly powerful in multimedia transmitting and browsing. However, the small screen and different
aspect ratios of mobile devices lower visual quality while watching images or videos. Video retargeting is aim at fitting
an existing video into arbitrary size and aspect ratio. Previous content-aware retargeting methods are mostly high computational
cost, which limits their applications on the portable devices with low computation ability. In this paper, a new crop-and-scale
approach is presented to adapt video to better suit the target display. We automatically find the optimal parameters of cropping
window using the dynamic programming method, and then scale it to fit the target display. The cropping window can smoothly
shift during a shot to follow the movement of important objects. The retargeting results using our approach introduce no deformation
and jitter effects over the whole video. Experimental results show the success of our approach on adapting a variety of source
videos to small display sizes. 相似文献
146.
邱晓明 《徐州师范大学学报(哲学社会科学版)》2011,37(2):134-137
以地方政府为参加主体的流域排污权多方动态交易机制是排污权市场研究的一个空白点。应用特定的模型分析可以看到,在连续的动态交易机制下,给予流域地方政府足够时间和交易频率,排污权价格将会从非均衡价格趋向均衡价格,由此就会实现成本有效的排污权交易市场,从而可以降低流域总削污成本。同时,通过拍卖机制设计,也可以简化排污权多方连续动态交易机制,降低交易成本。 相似文献
147.
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
148.
A novel test access mechanism (TAM) architecture with multi test-channel (TC) based on IEEE Standard 1500 is proposed instead
of the traditional sub-TAM structure. The cost model of an area-time associated test and the corresponding lower bound of
system-on-chip (SoC) test time are established based on this TAM architecture. The model provides a more reliable method to
control the SoC scheduling and reduces the complexity in related algorithm research. The result based on the area time associated
test cost model has been validated using the ITC’02 test benchmark. 相似文献
149.
梁赞勋 《徐州师范大学学报(哲学社会科学版)》2011,37(5):1-5
从容闳与留美幼童这个重大事件所处时代及事件性质所具有的标志性来看,从解剖一个时代社会横断面的历史研究方法和留美幼童在中国留学史中所表现出的先锋、示范作用来看,容闳和留美幼童的足迹是值得我们努力追寻的。有关容闳与留美幼童历史的研究,十余年来取得了丰硕的成果,发现了不少值得探索的新课题。对容闳与留美幼童的研究作出重要贡献的单位和个人,都值得我们尊敬和学习。 相似文献
150.
医学领域研究型博士学位评价是对博士生经过3~5年学习之后形成的最终学习成果进行价值判断。为了探究医学领域研究型博士学位评价标准,我们采用德尔菲(Delphi)法,对22名专家进行两轮咨询。研究结果初步确立了医学领域研究型博士学位评价体系,包含4大要素、25项评价指标。本研究不仅为社会评价医学领域研究型博士学位提供统一的参考标准和导向,还为高校授予医学领域研究型博士学位提供一套实用的工具。 相似文献