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Large crowds at music festivals or other mass events create challenging environments for traditional infrastructure based wireless networks. Mobile devices carried by the attendees produce large amounts of network traffic that can result in network outage or serious delays. Opportunistic networks may offer solutions to enable communication between attendees and/or organizers through direct communication...
Edge detection in an image is one of the most important tasks when working with image recognition, object identification, feature extraction, among others. There are different metrics to evaluate edges, such as Pratt, Jaccard, Dice but all these metrics binarize the image, and by performing this action information is lost from the image. This paper presents a new method that will allow the evaluation...
In this paper, we propose an efficient soft-detector for spatial multiplexing multiple-input multiple-output systems. Maximum a posteriori probability detection employing QR decomposition with M algorithm (QRM-MAP) achieves improved performance by adopting unbiased minimum-mean-square error (UMMSE) preprocessing. The efficiency of QRM-MAP can be further improved by using statistical information obtained...
This paper presents a mechanism for inferring user behaviour from encrypted wireless network activity. Aside from being within range, this mechanism operates without any level of network access, and without the need to break any encryption. It demonstrates how an entirely passive, external observer can detect if and when a person is using Skype. It is further demonstrated that this detection ability...
A significant proportion of Web traffic is now attributed to Web robots, and this proportion is likely to grow over time. These robots may threaten the security, privacy, functionality, and performance of a Web server due to their unregulated crawling behavior. Therefore, to assess their impact, it must be possible to accurately detect Web robot requests. Contemporary detection approaches, however,...
We investigate the problem of sequence detection in a non linear channel for a contactless air interface. The work presented in this study is based on the the VHBR (Very High Bit-Rate) amendments of the ISO 14443 international standard. We focused more particularly on the part of the standard extension that defines the phase modulation (PSK) from the Proximity Coupling Device (PCD) to the Passive...
We report on our experience with model-based testing using SpecExplorer within the Flat X-Ray Detection (FXD) Department of Philips Healthcare. Our initial experiments showed a practical obstacle in combining traditional functional testing techniques with model-based testing using SpecExplorer. We overcome this obstacle by specifying the constraints on our data domain in a spreadsheet and interfacing...
Spectrum sensing is a fundamental problem in cognitive radio. How to sense the presence of primary user promptly in order to avoid the unexpected interference is a key issue to the system. The motivation of our work is to detect the primary user signal using small size data in short time. In this paper, a quickest detection based approach is proposed for spectrum sensing. This approach employs covariance...
Multi-h continuous-phase modulation (CPM) has been used in telecommunication and aeronautical telemetry system due to its high power and spectral efficiency. Nonetheless, the optimum MLSE receiver suffers from high implementation complexity. One-symbol differential trellis detector with Viterbi algorithm for multi-h CPM signal is proposed in this article, we derives a simple trellis to reduce the...
By exchanging soft information between the detector and the channel decoder, an iterative receiver can significantly improve the performance compared to the non-iterative receiver. In this paper, a low complexity soft-input soft-output (SISO) fixed-complexity sphere decoding (FSD) algorithm is proposed for iterative MIMO receiver. The algorithm introduces a simplified parallel candidate adding (SPCA)...
Self/Non-self discrimination is the basic mission of the artificial immune systems (AIS). In traditional AIS, detectors discriminate non-self elements based on the Minkowski distance between detectors and antigens. However, in high dimensional feature space the distances between elements converge to a similar value, so the data discrimination will become much difficult. In this article, the relationship...
Imaging of complex and dynamic processes such as two- or multiphase flows with high structural as well as temporal resolution has always been a challenging task. In recent years, the electron beam X-ray computed tomography technique has been developed towards a powerful imaging tool, which reaches frame rates of 8000 fps in 2D and 1000 fps in 3D. In this paper, the latest developments as well as selected...
A direct comparison of Josephson Voltage Standards (JVS) at 10 V between the Bureau International des Poids et Mesures (BIPM) and the Centro Nacional de Metrología (CENAM), México, was carried out in September 2011. This comparison is part of the BIPM key comparisons (BIPM.EM-K10.b), and took place in the new DC voltage laboratory of CENAM. The relative voltage difference between the two quantum standards...
We present a machine learning framework that automatically generates a model set of landmarks for some class of registered 3D objects: here we use human faces. The aim is to replace heuristically-designed landmark models by something that is learned from training data. The value of this automatically generated model is an expected improvement in robustness and precision of learning-based 3D landmarking...
Effective mitigation of the Insider Threat in complex organizations is not simply a matter of 'fire-and-forget'. Thorough routines are required to minimize the chances of malicious insiders going undetected. While detecting policy violations and signatures of known-bad behavior are essential to a broader threat mitigation strategy, it is clear that behavior-based measurements, including anomaly detection...
A novel low-complexity detection scheme is proposed for the multiple-input multiple-output (MIMO) single-carrier frequency division-multiple access (SC-FDMA) systems, which is suitable for ASIC implementations. The proposed detection scheme makes an initial estimate of the transmitted signal based on a minimum mean square error (MMSE) frequency domain equalizer (FDE) detector and finds symbols with...
Multiple-input multiple-output (MIMO) technique can significantly increase data throughput without sacrificing additional bandwidth. However, data detection at the receiver and its VLSI implementation is challenge due to high computation complexity. This paper presents the VLSI architecture and implementation for a 4×4 64-QAM soft-output K-Best MIMO detector. A novel deeply pipelined architecture...
A real-time infrared and visible image fusion system is developed. This system consists of detector system, image processing system, transmission system, display system and control system. Image processing system is based on FPGA and DSP with the function of image fusion. A "contrast stretching" grayscale fusion method and the "color transfer" color fusion method in YCrCb space...
Data centers are growing in size and complexity driven by trends such as cloud computing and on-line services. Such large data centers pose several challenges for system management. Key among them is anomaly detection which is required to monitor and analyze metrics across several thousands servers and across multiple layers of abstractions to detect anomalous system behavior. In practice, multiple...
Semiparametric detection consists of combining the statistical optimality of a parametric test to the robustness regarding the data of a nonparametric test. This approach is specially interesting in presence of statistical hypotheses depending on unknown probability distributions. The proposed semiparametric approach consists of splitting the measurement vector into two parts such that the first part...
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