15 resultados para Expressió facial

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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In this paper, a novel algorithm for removing facial makeup disturbances as a face detection preprocess based on high dimensional imaginal geometry is proposed. After simulation and practical application experiments, the algorithm is theoretically analyzed. Its apparent effect of removing facial makeup and the advantages of face detection with this pre-process over face detection without it are discussed. Furthermore, in our experiments with color images, the proposed algorithm even gives some surprises.

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Video-based facial expression recognition is a challenging problem in computer vision and human-computer interaction. To target this problem, texture features have been extracted and widely used, because they can capture image intensity changes raised by skin deformation. However, existing texture features encounter problems with albedo and lighting variations. To solve both problems, we propose a new texture feature called image ratio features. Compared with previously proposed texture features, e. g., high gradient component features, image ratio features are more robust to albedo and lighting variations. In addition, to further improve facial expression recognition accuracy based on image ratio features, we combine image ratio features with facial animation parameters (FAPs), which describe the geometric motions of facial feature points. The performance evaluation is based on the Carnegie Mellon University Cohn-Kanade database, our own database, and the Japanese Female Facial Expression database. Experimental results show that the proposed image ratio feature is more robust to albedo and lighting variations, and the combination of image ratio features and FAPs outperforms each feature alone. In addition, we study asymmetric facial expressions based on our own facial expression database and demonstrate the superior performance of our combined expression recognition system.

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Starting from the second-order finite volume scheme,though numerical value perturbation of the cell facial fluxes, the perturbational finite volume (PFV) scheme of the Navier-Stokes (NS) equations for compressible flow is developed in this paper. The central PFV scheme is used to compute the one-dimensional NS equations with shock wave.Numerical results show that the PFV scheme can obtain essentially non-oscillatory solution.

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The inducement of interface fracture is crucial to the analysis of interfacial adhesion between coating and substrate. For electroplated coating/metal substrate adhering materials with strong adhesion, interface cracking and coating spalling are difficult to be induced by conventional methods. In this paper an improved bending test named as T-bend test was conducted on a model coating system, i.e. electroplated chromium on a steel substrate. After the test, cross-sections of the coated materials were prepared to compare the failure behaviors under tensile strain and compressive strain induced by T-bend test. And the observation results show that coating cracking, interface cracking and partial spalling appear step by step. Based on experimental results, a new method may be proposed to rank the coated materials with strong inter-facial adhesion. (C) 2008 Elsevier B.V. All rights reserved.

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大豆 (Glycine max (L.) Meer.)是人们日常生活中不可缺少的食品,也是一种非常重要的油质、蛋白资源。目前根据大豆种子吸胀阶段对低温敏感性的不同,可将其划分成3种生态型:低温非敏感型、低温敏感型及中间型。对于低温非敏感型的种子来讲,4℃下吸胀24小时对其发芽率影响很小,而敏感型种子萌发率不超过5%。我国属于温带大陆性气候,大豆播种后由于温度波动而造成一部分种子不能萌发,最终导致减产甚至绝产的现象普遍存在。高产是育种工作的主要目标,提高逆境胁迫的适应能力是高产的前提和基础,所以从分子角度研究种子吸胀非常必要,一方面能够挖掘新的基因资源,另一方面为今后育种工作提供必要的理论依据。 本试验以此为立足点,低温吸胀非敏感型大豆品种 (Z22)为材料,利用cDNA-AFLP方法及蛋白质技术分离与低温吸胀相关的基因及蛋白,得到结果如下: 第一,本试验成功的分离出4个受低温诱导的基因,半定量RT-PCR方法进一步验证了这4个基因在种子吸胀24小时内受低温诱导。 第二,利用RACE方法成功的得到2个完整的全长基因,在NCBI数据库中查找后发现其中1个基因为新基因,命名为SCHI基因 (SCHI:Soybean chilling-induced gene)。SCHI全长为390bp,编码分子量大约为14.2KD的蛋白;另外一个基因是已知基因,其同源序列已经在其他的物种中得到分离。由于此基因与核糖体蛋白L34高度同源,所以把把这个基因命名为SOL34 (Soybean L34)。 第三,利用半定量RT-PCR方法对基因表达模型进行分析,结果表明:SCHI在种子低温吸胀18~24小时期间诱导表达量最高,而当种子低温吸胀24小时后转入常温下,其表达量在常温下18小时左右迅速下降;ABA (100μM)、PEG (30%,10000)及NaCl (250mM)能够诱导SCHI的表达,在诱导表达量上,ABA和PEG诱导效果最明显,而NaCl能够微弱的诱导此基因表达;对不同生态型的大豆品种而言,低温吸胀过程中,SCHI在非敏感型种子中的表达量高于敏感型种子,但非敏感型和中间型之间没有差别;另外,SCHI在大豆胚轴中是诱导型表达,在叶片和根尖中则是组成型表达。SOL34的表达在萌发前24小时内被低温诱导,但在不同生态型之间没有差别。SOL34在胚轴和根尖中受低温诱导,在叶片中是组成型表达。 第四,SCHI能够在原核生物中表达出相应蛋白,诱导表达蛋白的分子量在26-29KD,大约为理论值的2倍,说明在大肠杆菌中被表达的蛋白以2聚体形式存在。另外低温试验结果表明SCHI能够提高菌落忍耐短时间-20℃低温的能力。 第五,利用双元表达载体把SCHI转入拟南芥植株,经过低温、干旱和盐胁迫后,转基因植株的成活率均高于野生型植株。超表达SOL34的拟南芥植株降低了对低温的耐性;而抑制拟南芥中L34的表达反而提高了植株对低温的抗性。 第六,本试验利用蛋白质等有关试验检测了大豆种子低温吸胀时蛋白质发生的变化。从吸胀 (4℃和22℃下24h)后的大豆胚轴中成功鉴定出上调蛋白点25个,下调蛋白点15个。其中有参与能量代谢反应 (占10%,例如柠檬酸脱氢酶和苹果酸脱氢酶等)、细胞生长与分裂相关反应 (20%,例如LEA蛋白和种子成熟蛋白PM26)、胁迫反应 (10%,如乙醇脱氢酶)、种子宿命和贮藏蛋白 (20%,大豆球蛋白)等蛋白在此过程中发生了变化,暗示种子萌发前期低温吸胀过程中多种代谢发生变化。细胞生长变缓、能量代谢增强、胁迫代谢蛋白的高表达以及贮藏蛋白降解速度减慢等变化都有利于种子在吸胀过程中度过低温环境,为以后的生长作好准备。

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The East Asian respond with a marked facial flushing and mild to moderate symptoms of intoxication after drinking the amounts of alcohol that has no detectable effect on European. The alcohol sensitivity in Orientals is due to a delayed oxidation of aceta

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A new method of face recognition, based on Biomimetic Pattern Recognition and Multi-Weights Neuron Network, had been proposed. A model for face recognition that is based on Biomimetic Pattern Recognition had been discussed, and a new method of facial feature extraction also had been introduced. The results of experiments with BPR and K-Nearest Neighbor Rules showed that the method based on BPR can eliminate the error recognition of the samples of the types that not be trained, the correct rate is also enhanced.

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The crystal structure of the title complex salt has been determined by single-crystal X-ray structure analysis. The crystal data areas follows; Monoclinic, P2(1)/c, a=15.6480(10)Angstrom, b=16.7870(10)Angstrom, c=10.347(2)Angstrom, beta=90.790(10), V=2717.7(6)Angstrom(3), Z=3, and R=0.0333 for 4789 unique reflections. The complex anion has a pseudo-octahedral structure distorted more than the Cr-III and Co-III analogs, in which each, iminodiacetato ligand (ida(2-)) is coordinated in a facial fashion with the two N atoms in a cis configuration, resulting in an unsym-fac structure.

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In the present paper, the random inter facial waves in N-layer density-stratified fluids moving at different steady uniform speeds are researched by using an expansion technique, and the second-order a symptotic solutions of the random displacements of the density interfaces and the associated velocity potentials in N-layer fluid are presented based on the small amplitude wave theory. The obtained results indicate that the wave-wave second-order nonlinear interactions of the wave components and the second-order nonlinear interactions between the waves and currents are described. As expected, the solutions include those derived by Chen (2006) as a special case where the steady uniform currents of the N-layer fluids are taken as zero, and the solutions also reduce to those obtained by Song (2005) for second-order solutions for random interfacial waves with steady uniform currents if N=2.

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该文对统计不相关最优鉴别矢量集算法进行研究,在分析统计不相关最优鉴别矢量集算法的基础上提出了一种改进的方法。该方法在类内散布矩阵的特征空间中求解统计不相关最优鉴别矢量集。为了加快特征抽取速度,利用基于图像鉴别分析的维数压缩方法,对图像数据进行了压缩。在ORL和Yale人脸数据库的数值实验,验证本文所提出的方法的有效性。

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人脸识别是模式识别研究领域的重要课题,具有广阔的应用前景。本文提出了基于模糊神 经网络的人脸识别方法。首先用最优鉴别分析方法提取人脸的最优鉴别矢量集,构成特征空间,然后在 特征空间中设计模糊神经网络分类器。在ORL人脸图象库上的实验结果表明了该方法的有效性。

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对统计不相关最佳鉴别矢量集的本质进行研究 ,在基于总体散布矩阵特征分解的基础上 ,构造了一种白化变换 ,使得变换后的样本空间中的总体散布矩阵为单位矩阵 ,这样使得传统的最佳鉴别矢量集算法得到的均是具有统计不相关的最佳鉴别矢量集 ,从而揭示了统计不相关最佳鉴别变换的本质———白化变换加普通的线性鉴别变换。该方法的最大优点在于所获得的最优鉴别矢量同时具有正交性和统计不相关性。该方法对代数特征抽取具有普遍适用性。用ORL人脸数据库的数值实验 ,验证了该方法的有效性

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本文对广义最佳鉴别矢量的求解方法进行研究 ,根据矩阵的扰动理论 ,改进了郭提出的求解广义最佳鉴别矢量的一种迭代算法 ,提出了求解广义最佳鉴别矢量的一种新的迭代算法 .本文算法的一个突出优点是随着类别数目的增加 ,计算时间反而缩短 ;而老算法随着类别数目的增加计算时间随着增加 ;不仅如此 ,新算法的识别率不劣于老算法 .在 ORL人脸数据库的数值实验 ,验证了上述论断的正确性

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Whether facial identity and facial expression was processed independently has long been a controversy. Studies at levels of experimental, neuropsychological, functional imaging and cell-recording all failed to consistently support either independent or interdependent processing. Present study proposed that familiarity and discriminability of facial identity and expression was important variable in mediating the relation between facial identity and facial expression recognition. Effects of familiarity on recognition of facial identity and expression had been examined (e.g. Ganel & Goshen-Gottstein, 2004) but the role of the discriminability in recognition of facial identity and expression has not yet been carefully examined. To examine the role of discriminability of facial identity and expression, 8 experiments were conducted with Garner’s speeded classification task in recognition of identity and expression of unfamiliar faces. The discriminability of facial identity and expression was manipulated, and the measurements of Garner interference and facilitation indicated that: 1. The discriminability of facial identity and expression mediate the relation between facial identity and expression recognition. Four possible discriminability combinations between identity and expression predicted 4 interference patterns between them. Low discriminability accounted for the interference either in facial identity judgment or in facial expression judgment task. 2. The measurements of eye movements indicated that either in facial identity or in facial expression recognition low discriminability led to a narrowly-distributed eye fixation pattern while high discriminability led to a widely-distributed eye fixation pattern. 3. By combining the morphing technique with the Garner paradigm, study 2 successfully demonstrated the linar relation between discriminability and Garner facilitation effects, confirmed the discriminability effects in the measurements of Garner facilitation effects.. 4. By providing the varying information of facial expression, study 2 revealed that varying information improved the discriminability of facial expression, and then enhanced the recognition of facial expression. All the results indicated that the discriminability of facial identity and expression could mediate the independent or interdependent processing between them, and the discriminability effects on recognition of identity and expression of unfamiliar faces was identified. The results from interference effects and facilitation effects both indicated that the dimensional relation between facial identity and expression was separable but not asymmetric claimed by previous studies(Schweinberger et al, 1998, 1999). Absolutedly independent or interdependent processing between facial identity and expression recognition were both impossible, discriminability of identity and expression mediated the relation between them. The discriminability effects revealed in present study could explain the conflicts between existing findings well.

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Schizophrenia is a heritable disorder. However, molecular genetics and related research area have not unmasked the nature and mechanisms of this disorder. Therefore, many researchers begin to explore the pathology mechanism from other approaches. High-risk study is one of the promising approaches. In this study, we mainly focused on facial emotion perception in schizophrenia and their non-psychotic first-degree relatives, and attempted to explore whether facial emotion perception is the potential biological marker of schizophrenia. This dissertation comprises 4 studies. In the first study, we conducted a meta-analysis on behavioral data of facial emotion perception in schizophrenia. Our findings showed that patients demonstrated general deficits in both facial emotion perception and facial processing tasks. In the second study, sixty-nine patients with schizophrenia and 56 of their first-degree relatives (33 parents and 23 siblings), and 92 healthy controls (67 younger and 25 older healthy controls) completed a set of facial emotion perception tasks. The results validated that patients with schizophrenia displayed general deficits in facial emotion perception. Study two also demonstrated that siblings of patients performed equally well compared to the corresponding younger healthy controls in all the facial emotion perception tasks, while the parents of patients behaved significantly worse than the corresponding older healthy controls in the composite index of facial emotion perception tasks. The results suggest that relatives of patients display more severely declining in facial emotion perception with the increasing of age. In the third study, we used an automated voxel-wise technique, activation likelihood estimation (ALE) to provide an objective, quantitative evaluation of facial emotion processing in schizophrenia. Our findings demonstrated a marked under-recruitment of the amygdala, accompanied by a substantial limitation in activation in schizophrenia throughout a ventral temporal-basal ganglia-prefrontal cortex ‘social-brain’ system may be central to the difficulties patients experience when processing facial emotion. In the last study, we did an fMRI study about facial emotion perception in 12 patients with schizophrenia, 12 non-psychotic siblings of patients and 12 healthy controls. The results suggest that siblings of patients demonstrate abnormal activation in a variety of brain areas, including prefrontal gyrus, insula, parahippocampal gyrus and superior temporal gyrus. Taken together, the current findings suggest facial emotion perception may be a potential biological marker of schizophrenia.