Detailed Real-Time Urban 3D Reconstruction from Video

The paper presents a system for automatic, geo-registered, real-time 3D reconstruction from video of urban scenes. The system collects video streams, as well as GPS and inertia measurements in order to place the reconstructed models in geo-registered coordinates. It is designed using current state of the art real-time modules for all processing steps. It employs commodity graphics hardware and standard CPU’s to achieve real-time performance. We present the main considerations in designing the system and the steps of the processing pipeline. Our system extends existing algorithms to meet the robustness and variability necessary to operate out of the lab. To account for the large dynamic range of outdoor videos the processing pipeline estimates global camera gain changes in the feature tracking stage and efficiently compensates for these in stereo estimation without impacting the real-time performance. The required accuracy for many applications is achieved with a two-step stereo reconstruction process exploiting the redundancy across frames. We show results on real video sequences comprising hundreds of thousands of frames.     

Stereo using monocular cues within the tensor voting framework

We address the fundamental problem of matching in two static images. The remaining challenges are related to occlusion and lack of texture. Our approach addresses these difficulties within a perceptual organization framework, considering both binocular and monocular cues. Initially, matching candidates for all pixels are generated by a combination of matching techniques. The matching candidates are then embedded in disparity space, where perceptual organization takes place in 3D neighborhoods and, thus, does not suffer from problems associated with scanline or image neighborhoods. The assumption is that correct matches produce salient, coherent surfaces, while wrong ones do not. Matching candidates that are consistent with the surfaces are kept and grouped into smooth layers. Thus, we achieve surface segmentation based on geometric and not photometric properties. Surface overextensions, which are due to occlusion, can be corrected by removing matches whose projections are not consistent in color with their neighbors of the same surface in both images. Finally, the projections of the refined surfaces on both images are used to obtain disparity hypotheses for unmatched pixels. The final disparities are selected after a second tensor voting stage, during which information is propagated from more reliable pixels to less reliable ones. We present results on widely used benchmark stereo pairs.     

A decade of psychological publications relevant to Greece: Reflections on the state of Greek psychology.

Reviews the literature on the state of Greek psychology, classifying the publications listed in Psychological Abstracts from 1973 to 1983 into the following 4 major areas: clinical psychology, child psychology, social psychology, and psychohistoric psychology. It is concluded that the low number of psychological publications reflects the lethargic state of Greek psychology. It is argued that the lack of research in academic psychology is to a great degree responsible for the inadequate provision of efficient services, such as modernized basic education, mental health care, and social work in Greece. (8 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fluid in Video: Augmenting Real Video with Simulated Fluids

We present a technique for coupling simulated fluid phenomena that interact with real dynamic scenes captured as a binocular video sequence. We first process the binocular video sequence to obtain a complete 3D reconstruction of the scene, including velocity information. We use stereo for the visible parts of 3D geometry and surface completion to fill the missing regions. We then perform fluid simulation within a 3D domain that contains the object, enabling one‐way coupling from the video to the fluid. In order to maintain temporal consistency of the reconstructed scene and the animated fluid across frames, we develop a geometry tracking algorithm that combines optic flow and depth information with a novel technique for “velocity completion”. The velocity completion technique uses local rigidity constraints to hypothesize a motion field for the entire 3D shape, which is then used to propagate and filter the reconstructed shape over time. This approach not only generates smoothly varying geometry across time, but also simultaneously provides the necessary boundary conditions for one‐way coupling between the dynamic geometry and the simulated fluid. Finally, we employ a GPU based scheme for rendering the synthetic fluid in the real video, taking refraction and scene texture into account.     

地中海国家旅游规划政策的新趋势

本文对地中海各国政府和欧共体近期规划实践、研究进展以及过程进行回顾;对一些关键性规划和执行情况进行思考与评价,例如国家与地方在发展旅游业中的关系、旅游业投资、实施以及与其他规划的关系等;最后对上述地区各国的旅游规划进行比较.     

First order augmentation to tensor voting for boundary inference and multiscale analysis in 3D

Most computer vision applications require the reliable detection of boundaries. In the presence of outliers, missing data, orientation discontinuities, and occlusion, this problem is particularly challenging. We propose to address it by complementing the tensor voting framework, which was limited to second order properties, with first order representation and voting. First order voting fields and a mechanism to vote for 3D surface and volume boundaries and curve endpoints in 3D are defined. Boundary inference is also useful for a second difficult problem in grouping, namely, automatic scale selection. We propose an algorithm that automatically infers the smallest scale that can preserve the finest details. Our algorithm then proceeds with progressively larger scale to ensure continuity where it has not been achieved. Therefore, the proposed approach does not oversmooth features or delay the handling of boundaries and discontinuities until model misfit occurs. The interaction of smooth features, boundaries, and outliers is accommodated by the unified representation, making possible the perceptual organization of data in curves, surfaces, volumes, and their boundaries simultaneously. We present results on a variety of data sets to show the efficacy of the improved formalism.     

A modeling strategy for hybrid systems based on event structures

This paper considers hybrid systems which are continuous/discrete-time systems interacting with a decision maker which oversees the control and structure of the continuous/discrete-time system. These two segments combine with a processor which evaluates data to produce a three-segment model of a hybrid system having sufficient flexibility to represent a broad range of real-time situations and sufficient generality to incorporate the essential aspects of other models into a single framework. In particular the paper uses a graphically expressive controlled Petri net formulation of the decision maker and any of the usual models for the continuous/discrete-time system. Interaction between the systems occurs via three types of events: continuous/discrete-time events, decision-making events, and processor events. These types of events and their composition are rigorously defined to produce event structures and event histories. These events and event histories are used for the domain of interaction functions which specify the channels of communication between the three essential segments of the hybrid system. The event-based domains allow the disassociation of these communication channels from dependence on particular kinds of models or applications. The range of the interaction functions are binary vector-valued indicating the activation/deactivation processes in the respective segments. The entire modeling strategy is motivated by applications and models found in the literature especially flexible manufacturing systems and the C-net model of a hybrid system.This work was partially supported by the National Science Foundation under Grant No. ECS-8800910.     

Correspondence estimation for non-rigid point clouds with automatic part discovery

We propose an approach for estimating non-rigid correspondences between two shapes that can handle articulation and deformation of the surfaces to be matched. It operates on open or closed surfaces represented by point clouds and, therefore, it can be applied on other representations that can be converted into point clouds. Our method is capable of automatically discovering the articulated parts of the surface without requiring knowledge of the topology or the number of rigid parts. Processing begins by estimating potential sparse correspondences between the source and the target surface. These are used to align the largest corresponding parts of the two surfaces. Fragments of the surface that are not consistent with this alignment generate part hypotheses on which the algorithm is applied recursively. We present qualitative and quantitative results on four datasets comprising open and closed surfaces.     

Monounsaturated fatty acid oligomerization is responsible for the agglutination activity of heated virgin olive oil

The present study focuses on the isolation, purification and characterization of a molecule formed when virgin olive oil is heated at 130 °C for 24 h in air, that is found to be a strong agglutinin. The hemagglutinating activity of the novel molecule isolated from the heated olive oil was evaluated against human red blood cells (RBCs). Thin layer chromatography (TLC) of the oil mixture showed appearance of high molecular weight molecules, dimers and polymers. ¹³C nuclear magnetic resonance (NMR) and mass chromatography–mass spectroscopy (GC–MS) were used for structure elucidation. A linear oligomerization of monounsaturated fatty acids is involved. Light microscopy and electron microscopy were used to characterize and visualize the agglutination process. Agglutination without lysis or fusion was observed. The unheated olive oil and the isolated compound were also tested in-vitro against normal and malignant colon and breast cells. The results showed the highest reduction of tumor cells with the isolated novel compound. We conclude that virgin olive oil when heated in air produces oligomerization/polymerization of free unsaturated fatty acid possibly oleic acid (OA) that is a strong hemagglutinin against human RBCs with possible anti-cancer properties but with unknown nutritional effects on human health.