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The Software Defined Networking (SDN), an efficient network technology, allows researchers to program their networks to meet different application needs. In this paper, we focus on failure detection services in multiple SDN controllers. We review some classical failure detection services and discuss how these services work. These classical failure detection services have the high mistake rate problem...
In a Hybrid Dynamical System (HyDS) event occurrences can be generated by many causes. Also, these events may be controlled or uncontrolled (wanted or un-wanted) which in turn might generate imbalances and/or disorder in the system, with the potential of causing catastrophic faults. In order to be able to deal with controllable events regulation it is important solving an early detection problem,...
The estimation theory, in general, was developed to target three major applications. Smoothing, filtering and prediction. Linear estimators, thus can predict future outcomes of an event or set of events, based on a weighted sum of the past set of events. It is obvious that when the outcome has a steep change in the next step, the error in prediction increases. Using this property and applying it to...
We present a simple mathematical model of the dynamics of impurity distribution in liquid argon detectors. This model considers the dominant sources, sinks, and transport of the impurity between and within the gas and liquid phases of a large detector. We use this model to extract Henry's coefficients for oxygen and water from the time dependence of the impurity concentration in the liquid phase,...
Accurate quantification of gamma-ray source activity using CdZnTe-based imaging systems requires compensation of sensitivity loss mechanisms specific to large volume, pixelated CdZnTe detectors. Current sensitivity estimation methods are based on simulation, but the effects that reduce sensitivity are difficult to model and vary with detector-specific electric field profiles. A new, empirical method...
The X-ray observatory Athena (Advanced Telescope for High Energy Astrophysics) is an ESA satellite to be launched in 2028. One of the two focal plane instruments is the Wide Field Imager (WFI). WFI is an X-ray camera for imaging and spectroscopic applications. Its detector consists of active pixel DEPFET (Depleted P-channel Field Effect Transistors) sensors with front-end electronics. Mathematical...
Overcurrent relay is an important relay used to protect transmission and distribution feeders, transformer, bus coupler etc. It can be used as main or backup protection relays. The modeling of overcurrent relay and other protection relays is important in the research on the effects of network parameters and configurations on the operation of these relays. This research deal with modeling and simulation...
This paper presents a developed integrated study of the design, measurement and the application potential in phase locked loop (PLL) of a wideband MEMS phase detector. Cascaded transmission lines are adopted to realize wideband performance. Design equations are derived based on even/odd-mode analysis. Optimized structure is obtained by ANSYS simulation. The measurements focus on phase detection for...
Authors proved existence of uniformly most powerful invariant algorithm based on the t-test. Conducted study allowed to synthesize decision rule for detection of image features on 3×3 pixel patch was found. Simulation proved stability of the proposed feature point detection algorithm to change of mean value and standard deviation of background pixels' intensity. Versatility of detection algorithm...
We propose and analyze the resonant plasmonic terahertz detectors based on the split-gate field-effect transistors with electrically induced p-n junctions and graphene and perforated graphene channels. The perforation of the p-n junction depletion region leads to the tunneling suppression and the substantial reinforcement of the detector resonant response.
This paper compares the properties of traditional digital phase-locked loops based on multi-bit, high-resolution time-to-digital converters and those based on bang-bang phase detectors. Novel analysis is presented which show that bang-bang digital PLLs allow better phase noise and spur performance at lower power consumption, area and complexity. It will be also demonstrated that this property can...
Cognitive Radio (CR) Technology has emerged for the future of wireless communications, its key parameters of interest are frequency, power and modulation techniques. The Spectrum Sensing is an important task to determine the availability of the vacant channels. In Multicarrier Communication using Digital Signal Processing Techniques, Filter Bank Multi Carrier (FBMC) has an edge over other technologies...
In this paper, we analyze the performance of a cooperative cognitive radio network when secondary users (SUs) are operating in different environments. The variable operating conditions result in variable SNRs at each SU. Besides, closed forms of detection and false alarm probabilities are computed assuming that cognitive terminals are performing spectrum sensing using energy detection technique. Simulation...
The World Space Observatory (WSO) is a space-based ultraviolet (UV) telescope under development by Russia and Spain. Mexico is formalizing its participation in the development of components for some of the instruments on board, such as the detectors that are discussed in this work. In particular, this paper describes a first approach to a computational model of micro-channel plates (MCP), which are...
This paper reviews the types of cyber attacks in state estimation as well as detection and protection schemes. Recent studies show that adversaries can not only generate attack vectors, which can bypass the conventional detector, but can also optimize the attack vector to compromise least number of sensors. We examined four types of attack in state estimation process. Then, we examined least effort...
The integrity of messages in vehicular ad-hoc networks has been extensively studied by the research community, resulting in the IEEE~1609.2 standard, which provides typical integrity guarantees. However, the correctness of message contents is still one of the main challenges of applying dependable and secure vehicular ad-hoc networks. One important use case is the validity of position information...
Radiation source detection using a network of detectors is an active field of research for homeland security and defense applications. We propose Source-attractor Radiation Detection (SRD) method to aggregate measurements from a network of detectors for radiation source detection. SRD method models a potential radiation source as a “magnet”-like attractor that pulls in pre-computed virtual points...
We consider a decentralized binary detection architecture comprised of n local detectors (LDs) communicating their decisions to a Data Fusion Center (DFC). Each local detector (LD) declares preference for one of two hypotheses (H0 or H1) and transmits it to the DFC. The decision of the kth LD at time step t is utk. The DFC develops a global preference ut0 for one of hypotheses based on the vector...
Many image processing applications require to detect a known pattern buried under noise. While maximum correlation can be implemented efficiently using fast Fourier transforms, detection criteria that are robust to the presence of outliers are typically slower by several orders of magnitude. We derive the general expression of a robust detection criterion based on the theory of locally optimal detectors...
The use of a barometric pressure sensor in a wearable fall detector has been shown to improve the detection accuracy by determining the altitude change associated with the fall event. However, the barometer is a high-power-consuming sensor. This paper proposes a fall detection approach using a hermetically sealed and waterproof enclosure incorporating a small window covered by a semi-permeable membrane...
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