Bayesian algorithms have lately been used in a large variety of applications. This paper proposes a new methodology for hyperparameter initialization in the Variational Bayes (VB) algorithm. We employ a dual expectationmaximization (EM) algorithm as the initialization stage in the VB-based learning. In the first stage, the EM algorithm is used on the given data set while the second EM algorithm...

Novel functional possibilities, provided by recent data hiding technologies, carry out the danger of uncontrolled (unauthorized) and unlimited information exchange that might be used by people with unfriendly interests. The multimedia industry as well as the research community recognize the urgent necessity for network security and copyright protection, or rather the lack of adequate law for di...

Previous results on blind multiuser detection apply in situations where the signal parameters of the users of interest are known, and those of the interferers are unknown. In this paper, we consider the new paradigm of an -user system, in which users are active, and the problem is to detect users of interest out of those active users when the signal parameters (codes, amplitudes) of the users o...

In this paper, two probabilistic adaptive algorithms for jointly detecting active users in a DS-CDMA system are reported. The first one, which is based on the theory of hidden Markov models (HMM’s) and the Baum–Wech (BW) algorithm, is proposed within the CDMA scenario and compared with the second one, which is a previously developed Viterbi-based algorithm. Both techniques are completely blind ...

The release of image processing techniques make image modification and fakery easier. Image fakery, here, is defined as a process to copy a region of source image and paste it onto the destination image, with some post processing methods applied, such as boundary smoothing, blurring, etc. to make it natural. The most important characteristic of image fakery is object copy and paste. In order to...

Recently, there has been extensive research and development in the field of smart cars, including technologies related to autonomous driving. Various industries are actively working towards creating efficient safe self-driving cars. Sensor emerging prevent traffic accidents support driving complex environments where human perception may be limited. One representative being researched is use Fre...

The present experiments aimed to characterize the visual performance of subjects with long-standing, unilateral cortical blindness when walking in a naturalistic, virtual environment. Under static, seated testing conditions, cortically blind subjects are known to exhibit compensatory eye movement strategies. However, they still complain of significant impairment in visual detection during navig...

Direct adaptive realizations of the linear minimum mean-square error (MMSE) receiver for direct-sequence code-division multiple access possess the attractive feature of not requiring any explicit information of interference parameters such as timing, amplitudes, or spreading sequences; however, they need a training sequence for the desired user. Recently, a new blind adaptive receiver was propo...

Receivers for a variety of communication channels must often be designed to operate in the absence of channel information. While a channel estimate may be generated from training data, known data then occupies available spectrum, which is often a scarce resource. We propose a blind maximum likelihood (ML) sequence detection and decoding technique for which the receiver requires no training data...