The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Nonnegative Matrix Approximation (NNMA) is a very well known technique of multivariate data analysis. However, in its basic form it provides very little control over its behaviour. This article explores possible extensions to this method in the context of multiple frequency estimation: using a parameterized distortion measure, enforcing harmonic structure on the basis matrix and introducing additional...
In this paper, we will examine the problem of historical storage and diagnosis of massive numbers of simultaneous streams. Such streams are common in very large sensor systems which collect many data streams simultaneously. For example, in a typical monitoring application, we may desire to determine specific abnormalities at sensor nodes or diagnose local regions of abnormal behavior. In other applications,...
Random walk based graph sampling has been recognized as a fundamental technique to collect uniform node samples from a large graph. In this paper, we first present a comprehensive analysis of the drawbacks of three widely-used random walk based graph sampling algorithms, called re-weighted random walk (RW) algorithm, Metropolis-Hastings random walk (MH) algorithm and maximum-degree random walk (MD)...
We consider symbol rate estimation of an unknown signal linearly modulated by a sequence of symbols. We rely on the received signal is cyclostationarity, and consider an existing estimator obtained by maximizing in the cyclic domain a (possibly weighted) sum of modulus squares of cyclic correlation estimates. Although widely used, this estimate seems not to have been studied rigorously when the number...
Crowdsensing has been used quite regularly in recent years to study smartphone usage. However context information associated with smartphone usage is mostly of the type geo-localisation, user mobility, temporal behavior etc. Furthermore most studies are not sufficiently user-centric i.e. don't consider the perception or cognitive aspects of the user. In this paper we collect data about social context...
In this paper we present a method to structure contextual knowledge in spatial regions/manifolds that may be used in action selection for industrial robotic systems. The contextual knowledge is build on relatively few prior task executions and it may be derived from either teleoperation or previous action executions. We argue that our contextual representation is able to improve the execution speed...
A tremendous amount of information is being shared everyday on social media sites such as Facebook, Twitter, or Google+. Often times these social media texts include information that are valuable to others, such as activities (e.g., art fairs, jazz festivals, and gatherings), natural disaster occurrences (e.g., tornadoes, earthquakes), or incidents (e.g., traffic jams). However, current search on...
This paper evaluates the coding efficiency of the HM 13.0 HEVC rate-distortion optimizing (RDO) encoder before and after the context-adaptive binary arithmetic coding (CABAC) engine is replaced with the context-based arithmetic coding (CBAC) engine of AVS 2.0. In addition, the rate errors are controlled by varying the bit length of the fractional part for the estimated bit in the rate estimation table...
This paper presents a new dynamic model for fuzzy consensus that uses randomness in the modeling of the individual process iterations, this leads to singular (different) consensus process paths. The imprecision of the resulting different consensus results is captured by a simple process to form an overall consensus result from the distribution of the singular consensus results. The introduction of...
Location Based Social Networks (LBSNs) integrate location-based facilities with social connectivity for delivering a variety of services, enhancing user experience, emergency/ disaster management, and streamlining business processes. A number of recent research efforts have studied relationships between geolocation and social connectivity, social connectivity and preferences, and node attributes and...
In contrast to conventional studies of discovering hot spots, by analyzing geo-tagged images on Flickr, we introduce novel methods to discover obscure sightseeing spots that are less well-known while still worth visiting. To this end, we face two new challenges that the classical authority analysis based methods do not encounter: how to discover and rank spots on the basis of 1) popularity (obscurity...
This paper proposes an innovative method to detect micro aerial vehicles (MAVs) and estimate their relative pose in formation using a monocular on-board camera. Haar classifier is trained for autonomously detecting MAV in open scenes, like grasslands or obstruct-free playgrounds. In order to increase the robustness of the detection, a Kaiman filter has been employed to conduct image tracking. Contours...
In participatory sensing applications, the inaccuracy and conflict of the reported data, commonly caused by the error rate of participants or the differences of observation context, have received more and more attention. Estimating the real status of facilities according to observations becomes a big challenge for participatory sensing. Towards this end, we propose a context-aware estimation approach...
Dense point trajectories estimation is a challenging yet important problem due to its potential of supporting other fields, such as motion estimation, action recognition, etc. In previous work, dense motion trackers always estimate trajectories based on consecutive frames and ignore scene context prior, thereby suffering from inaccurate estimation. In this paper, we present a novel dense point trajectories...
The paper presents category classification of mobile travel applications accessible at the moment for tourists in application stores for most popular mobile operation systems (Android and iOS). The most interesting category is "Travel Guides" that combines "Information Resources" and "Location-Based Services" category. Authors propose application "Tourist assistant...
Bowhead whales generate low-frequency vocalizations in shallow-water Arctic environments. The propagation of these sounds is adequately described by normal mode theory. Indeed, at low-frequency the environment acts as a dispersive waveguide. The propagated signal can be modeled by a sum of normal modes, and the source position can be inferred from the different modal arrivals. However, this requires...
Silhouettes are frequently extracted and described to compose inputs for learning methods in solving human pose estimation problem. Although silhouettes extracted from background subtraction methods are usually noisy, the effect of noisy inputs to pose estimation accuracies is seldom studied. In this paper, we explore this problem. First, We compare performances of several image features widely used...
In this paper the authors evaluate in context of numerical calculations accuracy classical integer order and direct non-integer based order numerical algorithms of non-integer orders derivatives and integrals computations. Classical integer order based algorithm involves integer and fractional order differentiation and integration operators concatenation to obtain non-integer order. Riemann-Liouville...
Bayesian filtering often relies on a reduced system state relating to robot internal variables only. The exogenous variables and their effects on the measurement process are then encompassed within a global observation noise model. Even if Bayes filters proved to be robust to such approximations, special care has to be taken to handle some of these exogenous effects, usually by introducing complex...
Studies show that software developers often either misuse exception handling features or use them inefficiently, and such a practice may lead an undergoing software project to a fragile, insecure and non-robust application system. In this paper, we propose a context-aware code recommendation approach that recommends exception handling code examples from a number of popular open source code repositories...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.