Pixel-Level Alignment of Facial Images for High Accuracy Recognition Using Ensemble of Patches

The variation of pose, illumination and expression makes face recognition still a challenging problem. As a pre-processing in holistic approaches, faces are usually aligned by eyes. The proposed method tries to perform a pixel alignment rather than eye-alignment by mapping the geometry of faces to a reference face while keeping their own textures. The proposed geometry alignment not only creates a meaningful correspondence among every pixel of all faces, but also removes expression and pose variations effectively. The geometry alignment is performed pixel-wise, i.e., every pixel of the face is corresponded to a pixel of the reference face. In the proposed method, the information of intensity and geometry of faces are separated properly, trained by separate classifiers, and finally fused together to recognize human faces. Experimental results show a great improvement using the proposed method in comparison to eye-aligned recognition. For instance, at the false acceptance rate of 0.001, the recognition rates are respectively improved by 24% and 33% in Yale and AT&T datasets. In LFW dataset, which is a challenging big dataset, improvement is 20% at FAR of 0.1.Comment: 11 pages, 16 figures, 1 table, key-words: face recognition, pixel alignment, geometrical transformation, pose and expression variation, ensemble of patches, fusion of texture and geometr

Relationship between Helicobacter pylori infection and cardiac syndrome X

چکیده: زمینه و هدف: علت سندرم X قلبی (CSX) هنوز به طور کامل مشخص نمی باشد ولی احتمالاً اختلال عملکرد اندوتلیم و التهاب در پاتوژنز آن نقش مهمی بازی می کند و ممکن است بعضی عفونت ها در این فرآیند التهابی نقش داشته باشند. این مطالعه با هدف تعیین ارتباط عفونت با هلیکوباکترپیلوری و سندرم X قلبی انجام شد. روش بررسی: در این مطالعه مورد-شاهدی 54 بیمار با تشخیص سندرم X قلبی (گروه مورد) و 168 بیمار مراجعه کننده جهت جراحی الکتیو (گروه شاهد) در سال 1386 مورد بررسی قرار گرفتند. مشخصات بیماران و نوع بیماری آنان پس از تشخیص، از طریق مصاحبه با بیماران و همچنین داده های آزمایشگاهی و آنژیوگرافی جمع آوری گردید. سپس با روش ELISA تیتر آنتی بادی ضد هلیکوباکترپیلوری نمونه خون بیمار اندازه گیری شد. داده های به دست آمده با استفاده از آزمون های آماری آزمون کای دو و Mantel hanzel تجزیه و تحلیل گردید. یافته ها: میانگین سن بیماران مورد مطالعه 99/8±54/54 سال بود. بر اساس نتایج این مطالعه تعداد 44 نفر (5/81) از بیماران در گروه مورد و 95 نفر (5/56) در گروه شاهد سرولوژی مثبت از نظر هلیکوباکترپیلوری داشتند (001/0

D-concurrence bounds for pair coherent states

The pair coherent state is a state of a two-mode radiation field which is known as a state with non-Gaussian wave function. In this paper, the upper and lower bounds for D-concurrence (a new entanglement measure) have been studied over this state and calculated.Comment: 11 page

Video alignment using unsupervised learning of local and global features

In this paper, we tackle the problem of video alignment, the process of matching the frames of a pair of videos containing similar actions. The main challenge in video alignment is that accurate correspondence should be established despite the differences in the execution processes and appearances between the two videos. We introduce an unsupervised method for alignment that uses global and local features of the frames. In particular, we introduce effective features for each video frame by means of three machine vision tools: person detection, pose estimation, and VGG network. Then the features are processed and combined to construct a multidimensional time series that represent the video. The resulting time series are used to align videos of the same actions using a novel version of dynamic time warping named Diagonalized Dynamic Time Warping(DDTW). The main advantage of our approach is that no training is required, which makes it applicable for any new type of action without any need to collect training samples for it. For evaluation, we considered video synchronization and phase classification tasks on the Penn action dataset. Also, for an effective evaluation of the video synchronization task, we present a new metric called Enclosed Area Error(EAE). The results show that our method outperforms previous state-of-the-art methods, such as TCC and other self-supervised and supervised methods.Comment: 10 pages, 7 figure