With great potential for assisting radiological image interpretation and decision making, content-based image retrieval in the medical domain has become a hot topic in recent years. Many methods to enhance the performance of content-based medical image retrieval have been proposed, among which the relevance feedback (RF) scheme is one of the most promising. Given user feedback information, RF a...

آگاهی از میزان تاج‌پوشش درختان در مناطق شهری به‌علت تأثیرات آن کاهش آلودگی‌‌های هوا، آلودگی صوتی، جلوگیری باد، ذخیرة نزولات آسمانی، و کنترل رواناب‌های بسیار ضروری است. ازآن‌جا‌که استخراج با روش‌های دستی وقت‌گیر پرهزینه است، تکنیک‌های سنجش دور می‌توانند ابزار مناسبی برای تأمین این داده‌ها باشند. طبقه‌بندی شیء‌پایه، انتخاب پارامترهای بهینة قطعه‌بندی، به‌ویژه پارامتر مقیاس، اهمیت بسیاری دارد معمول...

Numerous methods or algorithms have been designed to solve the problem of nonlinear dimensionality reduction (NLDR). However, very few among them are able to embed efficiently ‘circular’ manifolds like cylinders or tori, which have one or more essential loops. This paper presents a simple and fast procedure that can tear or cut those manifolds, i.e. break their essential loops, in order to make...

Any treemap algorithm can be used to translate into a configuration, guaranteeing that the areas of the topological components of the configuration exactly match the (scaled) volumes of their high-dimensional counterparts. Function values between adjacent contours are interpolated using a standard Gaussian-weighted Laplacian. Exploring the Space of Visualizations By using the (scaled) volumes o...

Suppose the data consist of a set S of points xj , 1 ≤ j ≤ J , distributed in a bounded domain D ⊂ RN , where N and J are large numbers. In this paper an algorithm is proposed for checking whether there exists a manifold M of low dimension near which many of the points of S lie and finding such M if it exists. There are many dimension reduction algorithms, both linear and non-linear. Our algori...

اجرای موفقیت‌آمیز انواع مدل‌های در مقیاس منطقه‌ای به انتخاب نوع داده و الگوریتم مناسب بازمی‌گردد. این نکته، کنار ممکن‌نبودن اندازه‌گیری تمامی اجزای طبیعت، منجر شکل‌گیری تحولی بزرگ شیوة درک پدیده‌ها شده است. شیوه، می‌توان هر جزء از طبیعت را به‌صورت یک عدد کمّی هندسة فراکتال درآورد. پژوهش حاضر، به‌منظور بررسی بعد شبکة زهکشی روی سازندهای زمین‌شناسی حوضة دشت یزد‌ـ اردکان، هم‌زمان الگوریتم‌های جریان ...

 Similarity Pyramid: Browsing a Document Database with ildus Ahmadullin, Jan Allebach HP Laboratories HPL-2012-21 Document database management; document visual similarity; similarity pyramid; Isomap Managing large document databases has become an important task. Sorting documents with respect to their visual similarity and layout features, and visualization of the whole document database is a ...

Diffusion MRI (dMRI) provides rich information on the white matter of the human brain, enabling insight into neurological disease, normal aging, and neuroplasticity. We present BundleMAP, an approach to extracting features from dMRI data that can be used for supervised classification, regression, and hypothesis testing. Our features are based on aggregating measurements along nerve fiber bundle...

We present a novel approach for embedding general metric and nonmetric spaces into lowdimensional Euclidean spaces. As opposed to traditional multidimensional scaling techniques, which minimize the distortion of pairwise distances, our embedding algorithm seeks a low-dimensional representation of the data that preserves the structure (geometry) of the original data. The algorithm uses a hybrid ...