Three-Dimensional Extended Object Tracking and Shape Learning Using Gaussian Processes

In this study, we investigate the problem of tracking objects with unknown shapes using three-dimensional (3D) point cloud data. We propose a Gaussian process-based model to jointly estimate object kinematics, including position, orientation and velocities, together with the shape of the object for online and offline applications. We describe the unknown shape by a radial function in 3D, and induce a correlation structure via a Gaussian process. Furthermore, we propose an efficient algorithm to reduce the computational complexity of working with 3D data. This is accomplished by casting the tracking problem into projection planes which are attached to the object's local frame. The resulting algorithms can process 3D point cloud data and accomplish tracking of a dynamic object. Furthermore, they provide analytical expressions for the representation of the object shape in 3D, together with confidence intervals. The confidence intervals, which quantify the uncertainty in the shape estimate, can later be used for solving the gating and association problems inherent in object tracking. The performance of the methods is demonstrated both on simulated and real data. The results are compared with an existing random matrix model, which is commonly used for extended object tracking in the literature

Primjena metode konačnih elemenata za modeliranje drvno-plastičnih kompozita ojačanih vlaknima za uporabu u konstrukciji namještaja s polukrutim vezovi

In this study, control samples of pine (Pinus slyvestris L.), beech (Fagus orientalis L.) and oak (Quercus petreae L.) species were obtained by using fi ber reinforced finger corner joints. Teknobont 200 epoxy and polyvinyl (PVAc) adhesives were used as glue. Bearing in mind the critical loads that may affect their use, experimental samples were tested under diagonal loads. Experimental samples were also analyzed by a computer program using the finite element method (FEM). Finally, experimental data were compared with the results of FEM. The comparisons clearly showed that experimental results and finite element solutions (SAP2000 V17) including semi-rigid connections are in good agreement. As a structural analysis program in furniture engineering designs, FEM can be preferred in terms of reliability and cost.U radu se prikazuju rezultati istraživanja uzoraka borovine (Pinus slyvestris L.), bukovine (Fagus orientalis L.) i hrastovine (Quercus petreae L.) spojenih kutnim zupčastim spojevima i ojačanih vlaknima. Kao ljepilo upotrijebljeno je epoksidno ljepilo Teknobont 200 i polivinilacetatno ljepilo (PVAc). Imajući na umu opterećenja koja se pojavljuju tijekom uporabe, eksperimentalni su uzorci ispitivani pri dijagonalnim opterećenjima. Uzorci su također analizirani računalnim programom primjenom metode konačnih elemenata (FEM). Eksperimentalni podatci i podatci dobiveni FEM analizom uspoređeni su te se jasno može vidjeti da se ti podatci za polukrute vezove podudaraju. Glede pouzdanosti i troškova, kao strukturnom programu analize u dizajniranju namještaja prednost se može dati FEM analizi

Extended Target Tracking and Classification Using Neural Networks

Extended target/object tracking (ETT) problem involves tracking objects which potentially generate multiple measurements at a single sensor scan. State-of-the-art ETT algorithms can efficiently exploit the available information in these measurements such that they can track the dynamic behaviour of objects and learn their shapes simultaneously. Once the shape estimate of an object is formed, it can naturally be utilized by high-level tasks such as classification of the object type. In this work, we propose to use a naively deep neural network, which consists of one input, two hidden and one output layers, to classify dynamic objects regarding their shape estimates. The proposed method shows superior performance in comparison to a Bayesian classifier for simulation experiments

Elastic foundation effects on arch dams

Earthquake response of an arch dam should be calculated under ground motion effects. This study presents three-dimensional linear earthquake response of an arch dam. Thereby, we considered different ground motion effects and also foundation conditions in the finite element analyses. For this purpose, the Type 3 double curvature arch dam was selected for application. All numerical analyses are carried out by SAP2000 program for empty reservoir cases. In the scope of this study, linear modal time-history analyses are performed using three dimensional finite element model of the arch dam and arch dam-foundation interaction systems. According to numerical analyses, maximum horizontal displacements and maximum normal stresses are presented by dam height in the largest section. These results are evaluated for rigid and various elastic foundation conditions. Furthermore, near-fault and far-field ground motion effects on the selected arch dam are taken into account by different accelerograms obtained from the Loma Prieta earthquake at various distances

The Effects of Organizational Support in Team Working on Creativity and Personal Initiative of Employees

Organizational support is one of the important dimensions of team working concept. The culture that will encourage employees to take the initiative and be creative requires top management support. The research question of this study is how organizational support exerts influence on take the initiative by team members and creativity of the employees. Therefore, this study aims to shed light on the relationship among organizational support, creativity and personal initiative. As a result of test of the hypotheses, positive and significant relationships between Organizational Support and Creativity and between Organizational Support and Personal Initiative have been supported. Managerial implications of these results are that if the employees feel the support of the management, they will be willing to take the initiative and they will unleash their creative potentials

THE MEDIATOR EFFECT OF LOGISTICS PERFORMANCE INDEX ON THE RELATION BETWEEN GLOBAL COMPETITIVENESS INDEX AND GROSS DOMESTIC PRODUCT

Logistics sector plays a critical role in social and economic developments of a country. Therefore understanding the relationship among the logistic performance, competitiveness and prosperity of a country is important. Logistics Performance Index (LPI) firstly published by World Bank in 2007 and repeated in the years 2010, 2012, 2014. In this research the mediator effect of LPI on the relation between Global Competitiveness Index (GCI) and Gross Domestic Product (GDP) was aimed to analyze for the years 2007, 2010, 2012, 2014. The mediator effect was measured by using hierarchical regression analyses. As a result of the analyses, the mediator effect of LPI on the relation between GCI and GDP was found statistically meaningful. Consequently, the result of the research could be suggested that the logistics ability of a country dominated the relation between competitiveness and prosperity

An investigation on the effects of time integration schemes on weakly compressible SPH method

Temporal discretization is a key aspect of the weakly compressible Smoothed Particle H drodynamics (SPH) method, as existing studies prove that the time integration schemes affect the stability of the simulations of weakly compressible SPH [1]. In this study, accuracy and performance of the classical 4th order Runge-Kutta method as a time integration scheme was evaluated by comparing simulation results of 2D dam break problem in terms of pressure and free surface profiles with single step (Euler method), predictor-corrector (midpoint) schemes and existing simulation results given in the literature. Density correction algorithm was utilized as a baseline treatment to prevent density fluctuations. The effect of Artificial Particle Displacement (APD) algorithm is another numerical treatment which is investigated in the present work. It is observed that APD provides more homogeneous particle distribution, leading to a higher accuracy. As for the comparison between time integration schemes, results based on the free surface deformation indicate that the Runge-Kutta method achieves success at reducing the free surface particle scattering encountered on Euler and midpoint schemes

The Role of Visual Features in Text-Based CAPTCHAs: An fNIRS Study for Usable Security

To mitigate dictionary attacks or similar undesirable automated attacks to information systems, developers mostly prefer using CAPTCHA challenges as Human Interactive Proofs (HIPs) to distinguish between human users and scripts. Appropriate use of CAPTCHA requires a setup that balances between robustness and usability during the design of a challenge. The previous research reveals that most usability studies have used accuracy and response time as measurement criteria for quantitative analysis. The present study aims at applying optical neuroimaging techniques for the analysis of CAPTCHA design. The functional Near-Infrared Spectroscopy technique was used to explore the hemodynamic responses in the prefrontal cortex elicited by CAPTCHA stimulus of varying types. )e findings suggest that regions in the left and right dorsolateral and right dorsomedial prefrontal cortex respond to the degrees of line occlusion, rotation, and wave distortions present in a CAPTCHA. The systematic addition of the visual effects introduced nonlinear effects on the behavioral and prefrontal oxygenation measures, indicative of the emergence of Gestalt effects that might have influenced the perception of the overall CAPTCHA figure.Comment: 24 pages, 32 figures, Computational Intelligence and Neuroscienc