Artykuły w czasopismach: „Channel tracking”

1

Kao, Yang-Ta, Hsiau-Wen Lin i Dai-Yi Qiu. "Implementation of Offline Consumer Behavior Tracking". International Journal of Pattern Recognition and Artificial Intelligence 35, nr 09 (4.05.2021): 2150028. http://dx.doi.org/10.1142/s0218001421500282.

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Due to declining trading volume growth in e-commerce platforms, physical channels have attracted considerable investments from various large international companies (e.g. Alibaba, JD, Walmart, Wanda, and Wuzhou International). However, e-commerce platforms can track consumers’ behaviors (attraction to landing page design, clicks on certain products, consumer behavior trajectory tracking, clicks on advertisements, and internal link optimization of product pages), a feat unachievable in current physical channels. Consequently, this study attempted to apply the characteristics of online channels in a physical channel by using image object tracking and image detection techniques. Through this inclusion, physical channels are capable of providing consumers with more favorable experience and interaction, and brick-and-mortar store owners can obtain a more accurate understanding of consumer behaviors of store consumers. Information acquired through this system can be provided to store owners to serve as reference for merchandise placement, arrangement of display shelves, and consumer circulation path planning. This study used the technique of image processing to locate the Region of Interest and applied object tracking to get the consumer’s trajectory which successfully implemented the consumer-tracking characteristics of online platforms in a physical channel while retaining the unique experience of the physical channel. This results in a win–win scenario for businesses and consumers.

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Kohli, Amit Kumar, Amrita Rai i Meher Krishna Patel. "Variable Forgetting Factor LS Algorithm for Polynomial Channel Model". ISRN Signal Processing 2011 (30.12.2011): 1–4. http://dx.doi.org/10.5402/2011/915259.

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Variable forgetting factor (VFF) least squares (LS) algorithm for polynomial channel paradigm is presented for improved tracking performance under nonstationary environment. The main focus is on updating VFF when each time-varying fading channel is considered to be a first-order Markov process. In addition to efficient tracking under frequency-selective fading channels, the incorporation of proposed numeric variable forgetting factor (NVFF) in LS algorithm reduces the computational complexity.

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Li, Yongzhi, Cheng Tao, Yapeng Li, Liu Liu i Tao Zhou. "Investigation of Sphere Decoder and Channel Tracking Algorithms for Media-Based Modulation over Time-Selective Channels". Wireless Communications and Mobile Computing 2017 (2017): 1–11. http://dx.doi.org/10.1155/2017/2509824.

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The performance of media-based modulation (MBM) systems, where additional information can be conveyed by the indices of the channel states created by RF mirrors, over time-selective channels is investigated. By transforming the MBM system model into a traditional MIMO system model, we first propose a reduced complexity sphere decoder algorithm. Then two channel tracking algorithms, which are based on least mean square adaptive filter and recursive least-squares adaptive filter, are employed in order to combat the performance loss caused by the time-varying channels. Numerical results show that the proposed sphere decoder and these two channel tracking algorithms perform well in MBM systems.

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Vollmer, Mario, Swen Zaremba, Pierre Mertiny i Klaus Drechsler. "Edge Race-Tracking during Film-Sealed Compression Resin Transfer Molding". Journal of Composites Science 5, nr 8 (21.07.2021): 195. http://dx.doi.org/10.3390/jcs5080195.

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Edge race-tracking is a frequently reported issue during resin transfer molding. It is caused by highly permeable channels and areas between the preform edge and cavity, which can significantly change the preform impregnation pattern. To date, information is scarce on the effect of edge race-tracking in compression resin transfer molding (CRTM). To close this gap, laboratory equipment was developed to study the CRTM preform impregnation via flow visualization experiments. The preform was thereby encapsulated in thin thermoplastic films sealing its impregnation. Film-sealed compression resin transfer molding (FS-CRTM) experiments of preforms with a small geometrical aspect ratio showed fast filling of the injection gap and a subsequent through-thickness preform impregnation. Creating an edge race-tracking channel, an additional lateral in-plane flow from the channel towards the preform center was observed, initiating soon after the injection started and caused by the spatial connection between the injection gap and the race-tracking channel. To diminish edge race-tracking, a passive flow control strategy was implemented via a split design of the upper tool to spatially isolate the injection gap from the channel and to pre-compact the preform edge. A delayed and reduced lateral race-tracking flow was observed, showing that the passive flow control strategy increases the process robustness of FS-CRTM regarding edge race-tracking effects.

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Yu, Jiyong, Mengjia Yan, Artem Khyzha, Adam Morrison, Josep Torrellas i Christopher W. Fletcher. "Speculative taint tracking (STT)". Communications of the ACM 64, nr 12 (grudzień 2021): 105–12. http://dx.doi.org/10.1145/3491201.

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Speculative execution attacks present an enormous security threat, capable of reading arbitrary program data under malicious speculation, and later exfiltrating that data over microarchitectural covert channels. This paper proposes speculative taint tracking (STT), a high security and high performance hardware mechanism to block these attacks. The main idea is that it is safe to execute and selectively forward the results of speculative instructions that read secrets, as long as we can prove that the forwarded results do not reach potential covert channels. The technical core of the paper is a new abstraction to help identify all micro-architectural covert channels, and an architecture to quickly identify when a covert channel is no longer a threat. We further conduct a detailed formal analysis on the scheme in a companion document. When evaluated on SPEC06 workloads, STT incurs 8.5% or 14.5% performance overhead relative to an insecure machine.

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YANG, QINGHAI, i KYUNG SUP KWAK. "PILOT-AIDED MULTIUSER CHANNEL ESTIMATION AND TRACKING IN MIMO-OFDM SYSTEMS". Journal of Circuits, Systems and Computers 16, nr 03 (czerwiec 2007): 319–35. http://dx.doi.org/10.1142/s0218126607003691.

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This paper addresses the pilot-aided multiuser least square (LS) channel estimation for the uplink of multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) systems. The systems under consideration allow all users use all available subcarriers independently and thus involve multiuser interference in the frequency domain. Direct application of the known pilot-aided single-user channel estimation methods to these systems is prohibited, requiring much more new investigations. The decentralized and centralized channel estimation algorithms are developed according to different multiuser scenarios. Optimal multiuser pilots are proposed, especially for centralized estimation methods with respect to the mean square error (MSE) of LS channel estimate. In addition, channel tracking algorithms are represented in terms of individual user's channels.

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Dahiya, Suresh, i Arun Kumar Singh. "Channel estimation and channel tracking for correlated block-fading channels in massive MIMO systems". Digital Communications and Networks 4, nr 2 (kwiecień 2018): 138–47. http://dx.doi.org/10.1016/j.dcan.2017.07.006.

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Pham, Phuong Thi Thu, i Tomohisa Wada. "Effective Scheme of Channel Tracking and Estimation for Mobile WiMAX DL-PUSC System". Journal of Computer Systems, Networks, and Communications 2010 (2010): 1–9. http://dx.doi.org/10.1155/2010/806279.

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This paper introduces an effective joint scheme of channel estimation and tracking for downlink partial usage of subchannel (DL-PUSC) mode of mobile WiMAX system. Based on the pilot pattern of this particular system, some channel estimation methods including conventional interpolations and a more favorable least-squares line fitting (LSLF) technique are comparatively studied. Besides, channel estimation performance can be remarkably improved by taking advantage of channel tracking derived from the preamble symbol. System performances in terms of packet error rate (PER) and user link throughput are investigated in various channels adopted from the well-known ITU models for mobile environments. Simulation results show a significant performance enhancement when the proposed joint scheme is utilized, at least 5 dB, compared to only commonly used channel estimation approaches.

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Siddiq, Abdulrahman Ikram. "Variable Length Cyclic Prefix OFDM using Multipath Delay Tracking". Tikrit Journal of Engineering Sciences 18, nr 2 (30.06.2011): 12–21. http://dx.doi.org/10.25130/tjes.18.2.02.

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The Cyclic Prefix (CP) technique is widely used in Orthogonal Frequency Division Multiplexing (OFDM) systems. A CP of length greater than the channel order guarantees the orthogonality of the consecutive OFDM symbols. Therefore, the effects of Inter Symbol Interference (ISI) and Inter Carrier Interference (ICI) are cancelled. On the other hand, CP reduces the transmission efficiency.Conventional OFDM systems use constant length CP. For time varying channels, CP length may become shorter than channel order resulting in considerable loss in orthogonality and performance degradation. Otherwise, when CP length becomes much greater than channel order it results with time and power wasting, and hence decreasing transmission efficiency.This paper proposes the usage of a multipath delay-tracking module to provide the OFDM system with the actual channel order and accordingly the suitable CP length will be determined. Computer simulations show that the proposed system saves about 47.6% of the time and power spent by the same constant length CP OFDM system tested under the same conditions.

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Becker, Johannes K., David Li i David Starobinski. "Tracking Anonymized Bluetooth Devices". Proceedings on Privacy Enhancing Technologies 2019, nr 3 (1.07.2019): 50–65. http://dx.doi.org/10.2478/popets-2019-0036.

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Abstract Bluetooth Low Energy (BLE) devices use public (non-encrypted) advertising channels to announce their presence to other devices. To prevent tracking on these public channels, devices may use a periodically changing, randomized address instead of their permanent Media Access Control (MAC) address. In this work we show that many state-of-the-art devices which are implementing such anonymization measures are vulnerable to passive tracking that extends well beyond their address randomization cycles. We show that it is possible to extract identifying tokens from the pay-load of advertising messages for tracking purposes. We present an address-carryover algorithm which exploits the asynchronous nature of payload and address changes to achieve tracking beyond the address randomization of a device. We furthermore identify an identity-exposing attack via a device accessory that allows permanent, non-continuous tracking, as well as an iOS side-channel which allows insights into user activity. Finally, we provide countermeasures against the presented algorithm and other privacy flaws in BLE advertising.

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Tami, Abdelkader, Mokhtar Keche i Boubaker S. Bouazza. "New OSTBC for Blind Channel Estimation and Tracking in MIMO-OFDM Systems". Journal of Telecommunications and Information Technology 3 (30.09.2019): 49–57. http://dx.doi.org/10.26636/jtit.2019.133819.

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Applying orthogonal space time block coding (OSTBC) to multiple-input multiple-output (MIMO) systems helps reduce receiver complexity. However, this approach has been applied only to ﬂat fading channels, as when the channel is a frequency selective fading MIMO channel, OSTBC cannot be used directly since its orthogonal propriety may be lost. Furthermore, the MIMO channel is not always known. To deal with this problem, many techniques were proposed to estimate the channel using a training sequence. Unfortunately, these techniques reduce the useful spectral bandwidth. This paper proposes OSTBC for blind channel estimation and data detection in the case of a MIMO frequency selective channel. The aim of this new OSTBC is twofold: to solve the ambiguity of channel estimation and to reduce the complexity of the detector. By exploiting the well-known technique of orthogonal frequency division multiplexing (OFDM), the frequency selective fading MIMO channel is split into a set of ﬂat fading subchannels. Moreover, to accommodate the fact that a MIMO channel can be time varying, the steady state Kalman channel estimator (SS-KCE) is extended to track the channel’s fast variations. The performance of the proposed blind algorithm is related by the adequate choice of the number of subcarriers and it is compared with other existing approaches by means of Monte Carlo simulations.

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Zhao, Long, Meng Zhu, Honge Ren i Lingjixuan Xue. "Channel Exchanging for RGB-T Tracking". Sensors 21, nr 17 (28.08.2021): 5800. http://dx.doi.org/10.3390/s21175800.

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It is difficult to achieve all-weather visual object tracking in an open environment only utilizing single modality data input. Due to the complementarity of RGB and thermal infrared (TIR) data in various complex environments, a more robust object tracking framework can be obtained using video data of these two modalities. The fusion methods of RGB and TIR data are the core elements to determine the performance of the RGB-T object tracking method, and the existing RGB-T trackers have not solved this problem well. In order to solve the current low utilization of information intra single modality in aggregation-based methods and between two modalities in alignment-based methods, we used DiMP as the baseline tracker to design an RGB-T object tracking framework channel exchanging DiMP (CEDiMP) based on channel exchanging. CEDiMP achieves dynamic channel exchanging between sub-networks of different modes hardly adding any parameters during the feature fusion process. The expression ability of the deep features generated by our data fusion method based on channel exchanging is stronger. At the same time, in order to solve the poor generalization ability of the existing RGB-T object tracking methods and the poor ability in the long-term object tracking, more training of CEDiMP on the synthetic dataset LaSOT-RGBT is added. A large number of experiments demonstrate the effectiveness of the proposed model. CEDiMP achieves the best performance on two RGB-T object tracking benchmark datasets, GTOT and RGBT234, and performs outstandingly in the generalization testing.

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Gamal El-Din, Tamer M., Todd Scheuer i William A. Catterall. "Tracking S4 movement by gating pore currents in the bacterial sodium channel NaChBac". Journal of General Physiology 144, nr 2 (28.07.2014): 147–57. http://dx.doi.org/10.1085/jgp.201411210.

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Voltage-gated sodium channels mediate the initiation and propagation of action potentials in excitable cells. Transmembrane segment S4 of voltage-gated sodium channels resides in a gating pore where it senses the membrane potential and controls channel gating. Substitution of individual S4 arginine gating charges (R1–R3) with smaller amino acids allows ionic currents to flow through the mutant gating pore, and these gating pore currents are pathogenic in some skeletal muscle periodic paralysis syndromes. The voltage dependence of gating pore currents provides information about the transmembrane position of the gating charges as S4 moves in response to membrane potential. Here we studied gating pore current in mutants of the homotetrameric bacterial sodium channel NaChBac in which individual arginine gating charges were replaced by cysteine. Gating pore current was observed for each mutant channel, but with different voltage-dependent properties. Mutating the first (R1C) or second (R2C) arginine to cysteine resulted in gating pore current at hyperpolarized membrane potentials, where the channels are in resting states, but not at depolarized potentials, where the channels are activated. Conversely, the R3C gating pore is closed at hyperpolarized membrane potentials and opens with channel activation. Negative conditioning pulses revealed time-dependent deactivation of the R3C gating pore at the most hyperpolarized potentials. Our results show sequential voltage dependence of activation of gating pore current from R1 to R3 and support stepwise outward movement of the substituted cysteines through the narrow portion of the gating pore that is sealed by the arginine side chains in the wild-type channel. This pattern of voltage dependence of gating pore current is consistent with a sliding movement of the S4 helix through the gating pore. Through comparison with high-resolution models of the voltage sensor of bacterial sodium channels, these results shed light on the structural basis for pathogenic gating pore currents in periodic paralysis syndromes.

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Nechyporuk-Zloy, Volodymyr, Peter Dieterich, Hans Oberleithner, Christian Stock i Albrecht Schwab. "Dynamics of single potassium channel proteins in the plasma membrane of migrating cells". American Journal of Physiology-Cell Physiology 294, nr 4 (kwiecień 2008): C1096—C1102. http://dx.doi.org/10.1152/ajpcell.00252.2007.

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Cell migration is an important physiological process among others controlled by ion channel activity. Calcium-activated potassium channels (KCa3.1) are required for optimal cell migration. Previously, we identified single human (h)KCa3.1 channel proteins in the plasma membrane by means of quantum dot (QD) labeling. In the present study, we tracked single-channel proteins during migration to classify their dynamics in the plasma membrane of MDCK-F cells. Single hKCa3.1 channels were visualized with QD- or Alexa488-conjugated antibodies and tracked at the basal cell membrane using time-lapse total internal reflection fluorescence (TIRF) microscopy. Analysis of the trajectories allowed the classification of channel dynamics. Channel tracks were compared with those of free QD-conjugated antibodies. The size of the label has a pronounced effect on hKCa3.1 channel diffusion. QD-labeled channels have a (sub)diffusion coefficient DQDbound= 0.067 μm2/sα, whereas that of Alexa488-labeled channels is DAlexa= 0.139 μm2/s. Free QD-conjugated antibodies move much faster: DQDfree= 2.163 μm2/sα. Plotting the mean squared distances (msd) covered by hKCa3.1 channels as a function of time points to the mode of diffusion. Alexa488-labeled channels diffuse normally, whereas the QD-label renders hKCa3.1 channel diffusion anomalous. Free QD-labeled antibodies also diffuse anomalously. Hence, QDs slow down diffusion of hKCa3.1 channels and change the mode of diffusion. These results, referring to the role of label size and properties of the extracellular environment, suggest that the pericellular glycocalyx has an important impact on labels used for single molecule tracking. Thus tracking fluorescent particles within the glycocalyx opens up a possibility to characterize the pericellular nanoenvironment.

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Khizhniak, A. V. "COMPLEXING IMAGES IN A TWO-CHANNEL OPTICAL-ELECTRONIC SYSTEM AS A METHOD OF REDUCING THE PROBABILITY OF DISAPPOINTING AN AUTOMATIC SURVEILLANCE OF LOW CONTRAST OBJECTS". Doklady BGUIR, nr 7 (125) (7.12.2019): 121–28. http://dx.doi.org/10.35596/1729-7648-2019-125-7-121-128.

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The paper discusses the work of the correlation algorithm for automatically tracking objects of interest in a two-channel optical-electronic system in a complex background-target environment and the presence of intentional interference. Conditions in which the contrast of the desired object in both channels is negligible but not equal to zero are considered difficult in the paper. Intentional interference refers to masking interference of natural and artificial origin, which helps to reduce the contrast of the object in both channels. By two-channel means an optical-electronic system, which includes channels of the visible and infrared ranges. It is believed that the multi-spectral images of both channels are reduced to a single time and scale, which allows them to be integrated using various methods. The purpose of this paper is to prove that the likelihood of disruption of automatic tracking is reduced when complexing the source images of the visible and infrared ranges, when the contrast of the desired object in both channels is negligible. For research the mathematical apparatus of the theory of random functions and simulation with subsequent statistical data processing are used. It is shown that the probability of disruption, characterized by the ratio of the correlation coefficients of two fragments of images, one of which contains the desired object, and the second not, depends on both the correlation coefficients and the values of their mean square deviations. The simulation shows that the breakdown of tracking occurs both when the mean square deviations of these correlation coefficients are equal, and at their different values, moreover, an increase in their difference increases the probability of a breakdown. The article shows that the likelihood of a breakdown in a two-channel optoelectronic system will decrease when using two channels, compared to working only in the visible or infrared channel. The obtained results substantiate the promise of using image complexing in multichannel systems of automatic tracking of objects in a complex background-target environment and the presence of deliberate interference.

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Chen, Honglin, Chunting Li i Chaomurilige. "Research on the Correlation Filter Tracking Model Based on the Deep-Pruned Feature Network". Applied Sciences 12, nr 22 (12.11.2022): 11490. http://dx.doi.org/10.3390/app122211490.

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Visual tracking is one of the key research fields in computer vision. Based on the combination of correlation filter tracking (CFT) model and deep convolutional neural networks (DCNNs), deep correlation filter tracking (DCFT) has recently become a critical issue in visual tracking because of CFT’s rapidity and DCNN’s better feature representation. However, DCNNs are often complex in structure, which most possibly results in the conflict between the rapidity and accuracy of DCFT. To reduce such conflict, this paper proposes a model mainly including: (1) Based on the pre-pruning network obtained by feature channel importance, an optimal global tracking pruning rate (GTPR) is determined in terms of the contribution of filter channels to tracking response. (2) Based on (GTPR), an alternative convolutional kernel is defined to replace non-important channel kernels, which leads to the further pruning of the feature network. (3) An online updating pruned feature network with a structural similarity index is employed to adapt the model to tracking scene changes. (4) The proposed model was performed on OTB2013; experimental results demonstrate the model can effectively enhance speed with a 45% increment while guaranteeing tracking accuracy, and improve tracking accuracy with a 4% increment when tracking scene changes take place.

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Nasir, Qassim, i S. Faisal Ali Shah . "Predictive LMS for Mobile Channel Tracking". Journal of Applied Sciences 5, nr 2 (15.01.2005): 337–40. http://dx.doi.org/10.3923/jas.2005.337.340.

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He, Zhiquan, i Xuejun Chen. "Object Tracking Based on Channel Attention". IEEE Access 8 (2020): 17824–32. http://dx.doi.org/10.1109/access.2020.2967031.

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Sheval, V. V., i A. I. Kimyaev. "STRUCTURAL ANALYSIS OF ON-BOARD MULTIMODE AUTO TRACKING SYSTEM". Vestnik komp'iuternykh i informatsionnykh tekhnologii, nr 204 (czerwiec 2021): 3–11. http://dx.doi.org/10.14489/vkit.2021.06.pp.003-011.

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Two variants of two-channel structures of tracking systems has been introduced into consideration, which are sequentially used in two modes of operation of the on-board automatic tracking system. Taking into account the fact of quantization according to the level of signals for measuring the angles of mismatch of each of the channels, it is justified to use not one, but two different structures in the second auto-tracking mode. Using mathematical modeling, the expediency of increasing the number of two-channel structures from two to three, used in a single auto-tracking process according to the criterion of the provided dynamic accuracy, have been demonstrated. This paper presents a two-channel structures investigation for tracking systems operating in tracking mode of maneuverable targets, taking into account various systems of carrier operations. Considered multichannel complex control system (CCS) structure that include precise channel (PC) and coarse channel (CC). CC use the carrier and the flight control system (FCS) to make rude tracking. The PC function implemented by an optoelectronic device (OED) has placed in a traditional angular mechanical suspension, which act with high accuracy. Described three CCS operation modes classified by target mark fall inside or outside direction finder (DF) CC or PC field of view. At the capture mode can be used only information from the CC DF. At the complex control mode becomes possible to use information from both CC DF and PC DF. At the precision mode, it is advisable to use information only from the PC DF. Developed CCS functioning math model to check main points of this work. Math model makes possible to carry out simulation tests for each mode in a separate operation, as well as when they are integrated into a single complex automatic target tracking mode. Has been described efficiency factor as the total time of satisfactory accuracy relative to entire experiment time. On math model modes efficiency has compared to each other. As result precision mode have higher efficiency and capture mode lowest. As conclusion recommended use a precision mode to achieve higher accuracy at auto tracking tasks.

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Huang, Kuan-Ying, Jyh-Ching Juang, Yung-Fu Tsai i Chen-Tsung Lin. "Efficient FPGA Implementation of a Dual-Frequency GNSS Receiver with Robust Inter-Frequency Aiding". Sensors 21, nr 14 (6.07.2021): 4634. http://dx.doi.org/10.3390/s21144634.

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Multiple frequency global navigation satellite system (GNSS) has become more complex due to the existence of extra channels. Typically, auxiliary methods are used to synchronize the second signals at other bands by aiding the acquired channel parameters. However, there are critical limitations because the reception of GNSS signals is subject to uncertainties due to noise carrier injection or circuit interference. The relationship between the two Doppler frequencies can be affected by uncertainties. Therefore, we aimed to implement an efficient dual-frequency field-programmable gate array (FPGA), performing a direct aid tracking method for the secondary channel to achieve resource efficiency and inner aid robustness. A robust estimator that directly links two loops in the two bands is proposed. In this scheme, (1) a robust estimator able to cope with uncertainty; (2) a primary tracking scheme to obtain the error boundary, and (3) a tracked bit-boundary for the initial code phase of the second channel are used. Based on experiments on the FPGA, the robust channel link can achieve direct aid tracking, and 31.02% of the original hardware resources from the aided acquisition module were released satisfactorily.

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Tian, Feng, Yang Bo Huang, Bo Xu i Gang Ou. "An Optimized Low-Power-Consumption Tracking Algorithm Based on Navigation Message Structure for Weak Signals". Applied Mechanics and Materials 733 (luty 2015): 854–59. http://dx.doi.org/10.4028/www.scientific.net/amm.733.854.

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In order to reduce the power consumption of handset GNSS receivers, we present a novel algorithm that tracks signals at fixed positions of the navigation message in an intermittent mode. The tracking channels only run during the beginning part of the message frame. In the rest they remain in idle state, to reduce power consumption of the channel. The beginning position of each message frame can be estimated accurately, and the beginning messages are constant or can be estimated, thus the coherent integration time can exceed one navigation bit, which can improve the Doppler frequency estimated accuracy. At the fixed position of the frame, the tracking channel only tracks the pseudo-code phase, and does not track the carrier frequency and phase. This algorithm can keep stable tracking for weak signals with 28 dBHz carrier-to-noise ratio (C/N0), while using only 2% of the power required by the computation associated with the traditional tracking.

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Fiaz, Mustansar, Arif Mahmood i Soon Ki Jung. "Learning Soft Mask Based Feature Fusion with Channel and Spatial Attention for Robust Visual Object Tracking". Sensors 20, nr 14 (20.07.2020): 4021. http://dx.doi.org/10.3390/s20144021.

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We propose to improve the visual object tracking by introducing a soft mask based low-level feature fusion technique. The proposed technique is further strengthened by integrating channel and spatial attention mechanisms. The proposed approach is integrated within a Siamese framework to demonstrate its effectiveness for visual object tracking. The proposed soft mask is used to give more importance to the target regions as compared to the other regions to enable effective target feature representation and to increase discriminative power. The low-level feature fusion improves the tracker robustness against distractors. The channel attention is used to identify more discriminative channels for better target representation. The spatial attention complements the soft mask based approach to better localize the target objects in challenging tracking scenarios. We evaluated our proposed approach over five publicly available benchmark datasets and performed extensive comparisons with 39 state-of-the-art tracking algorithms. The proposed tracker demonstrates excellent performance compared to the existing state-of-the-art trackers.

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Wang, Yu, Zhutian Yang, Wei Yang i Jiamin Yang. "A Novel Target Tracking Scheme Based on Attention Mechanism in Complex Scenes". Electronics 11, nr 19 (29.09.2022): 3125. http://dx.doi.org/10.3390/electronics11193125.

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In recent years, target tracking algorithms based on deep learning have realized significant progress, especially the Siamese neural network structure, which has a simple structure and excellent scalability. Although these methods provide excellent generalization capabilities, they fail to perform the task of learning target information discrimination smoothly due to being affected by distractors such as background clutter, occlusion, and target size. To solve this problem, in this paper we propose a newly improved Siamese network target tracking algorithm based on an attention mechanism. We introduce a channel attention module and a spatial attention module into the original network to improve the problem of insufficient semantic extraction ability of the convolutional layer of the tracking algorithm in complex environments. A channel attention mechanism enhances the feature extraction ability by using the network to learn the importance of each channel and establish the relationship between channels, while a spatial attention mechanism strengthens the feature extraction ability by establishing the importance of spatial position in locating the target or carrying out a certain degree of deformation. In this paper, the above two models are combined to improve the robustness of trackers without sacrificing tracking speed. We conduct a comprehensive experiment on the Object Tracking Benchmark dataset. The experimental results show that our algorithm outperforms other real-time trackers in both accuracy and robustness in most complex environments.

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Mei, Yixin, Fan Li, Lijun He i Liejun Wang. "Joint Source and Channel Rate Allocation over Noisy Channels in a Vehicle Tracking Multimedia Internet of Things System". Sensors 18, nr 9 (30.08.2018): 2858. http://dx.doi.org/10.3390/s18092858.

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As an emerging type of Internet of Things (IoT), multimedia IoT (MIoT) has been widely used in the domains of healthcare, smart buildings/homes, transportation and surveillance. In the mobile surveillance system for vehicle tracking, multiple mobile camera nodes capture and upload videos to a cloud server to track the target. Due to the random distribution and mobility of camera nodes, wireless networks are chosen for video transmission. However, the tracking precision can be decreased because of degradation of video quality caused by limited wireless transmission resources and transmission errors. In this paper, we propose a joint source and channel rate allocation scheme to optimize the performance of vehicle tracking in cloud servers. The proposed scheme considers the video content features that impact tracking precision for optimal rate allocation. To improve the reliability of data transmission and the real-time video communication, forward error correction is adopted in the application layer. Extensive experiments are conducted on videos from the Object Tracking Benchmark using the H.264/AVC standard and a kernelized correlation filter tracking scheme. The results show that the proposed scheme can allocate rates efficiently and provide high quality tracking service under the total transmission rate constraints.

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Fiaz, Mustansar, Arif Mahmood, Ki Yeol Baek, Sehar Shahzad Farooq i Soon Ki Jung. "Improving Object Tracking by Added Noise and Channel Attention". Sensors 20, nr 13 (6.07.2020): 3780. http://dx.doi.org/10.3390/s20133780.

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CNN-based trackers, especially those based on Siamese networks, have recently attracted considerable attention because of their relatively good performance and low computational cost. For many Siamese trackers, learning a generic object model from a large-scale dataset is still a challenging task. In the current study, we introduce input noise as regularization in the training data to improve generalization of the learned model. We propose an Input-Regularized Channel Attentional Siamese (IRCA-Siam) tracker which exhibits improved generalization compared to the current state-of-the-art trackers. In particular, we exploit offline learning by introducing additive noise for input data augmentation to mitigate the overfitting problem. We propose feature fusion from noisy and clean input channels which improves the target localization. Channel attention integrated with our framework helps finding more useful target features resulting in further performance improvement. Our proposed IRCA-Siam enhances the discrimination of the tracker/background and improves fault tolerance and generalization. An extensive experimental evaluation on six benchmark datasets including OTB2013, OTB2015, TC128, UAV123, VOT2016 and VOT2017 demonstrate superior performance of the proposed IRCA-Siam tracker compared to the 30 existing state-of-the-art trackers.

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Xu, Yue, Hang Yin i Yuanming Zhao. "Research on Multi-Channel Information Tracking Method". Academic Journal of Science and Technology 2, nr 2 (17.08.2022): 149–53. http://dx.doi.org/10.54097/ajst.v2i2.1304.

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This project provides a trajectory tracking method, device and computer storage medium, including associating the bottom database features of each target object with at least one trajectory feature to construct the identity association information of each target object; According to at least one track feature of each target object, each detection feature obtained from different target videos is identified, and the target object corresponding to each detection feature is determined; According to the identity association information of each target object and the target object of each detection feature, all detection features of the object to be queried are obtained by using any one of the track code and the base code of the object to be queried, and then the trajectory tracking results of the object to be queried are generated. According to this, the project can support the track tracking of multi-channel monitoring video, And it can effectively improve the accuracy and integrity of trajectory tracking results.

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Ragab, Ahmed, Yang Liu, Kangmin Hu, Patrick Chiang i Samuel Palermo. "Receiver Jitter Tracking Characteristics in High-Speed Source Synchronous Links". Journal of Electrical and Computer Engineering 2011 (2011): 1–15. http://dx.doi.org/10.1155/2011/982314.

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High-speed links which employ source synchronous clocking architectures have the ability to track correlated jitter between clock and data channels up to high frequencies. However, system timing margins are degraded by channel skew between clock and data signals and high-frequency loss. This paper describes how these key channel effects impact the jitter performance and influence the clocking architecture of high-speed source synchronous links. Tradeoffs in complexity and jitter tracking performance of common per-channel de-skew circuits are discussed, along with how band-pass filtering can be leveraged to provide additional jitter filtering at the receiver. Jitter tolerance analysis for a 10 Gb/s system shows that a near all-pass delay-locked loop (DLL) and phase-interpolator- (PI-) based de-skew performs best under low skew conditions, while, at high skew, architectures which leverage band-pass clock filtering or a phase-locked loop (PLL) for increased jitter filtering are more suitable. De-skew based on injection-locked oscillators (ILOs) offer a reduced complexity design and competitive jitter tolerance over a wide skew range.

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Chen, Jia, Yibo Ai, Yuhan Qian i Weidong Zhang. "A novel Siamese Attention Network for visual object tracking of autonomous vehicles". Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 235, nr 10-11 (29.03.2021): 2764–75. http://dx.doi.org/10.1177/09544070211006520.

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In the environment perception stage of autonomous driving, vehicles need to track its surrounding objects quickly and accurately to avoid dangerous behaviors. Therefore, visual object tracking has important practical application value in autonomous driving system. However, the performance of most hierarchical convolutional feature trackers are limited by ignoring the complex environment of autonomous driving. In this paper, a novel Siamese Attention Network to explore the rich spatial and channel information of objects was proposed. Because of the lack of important information between the channel and the spatial position, the tracking performance is reduced by the challenges of illumination change and deformation. The spatial attention block and channel attention block focus on the importance of different spatial positions and channels, respectively. The effective fusion of the two makes our tracker achieve the state-of-the art performance of 0.300 in the EAO criterion of 2017, which exceeds the baseline by 5.7%.

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Xu, Tianyang, Zhenhua Feng, Xiao-Jun Wu i Josef Kittler. "Adaptive Channel Selection for Robust Visual Object Tracking with Discriminative Correlation Filters". International Journal of Computer Vision 129, nr 5 (4.02.2021): 1359–75. http://dx.doi.org/10.1007/s11263-021-01435-1.

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AbstractDiscriminative Correlation Filters (DCF) have been shown to achieve impressive performance in visual object tracking. However, existing DCF-based trackers rely heavily on learning regularised appearance models from invariant image feature representations. To further improve the performance of DCF in accuracy and provide a parsimonious model from the attribute perspective, we propose to gauge the relevance of multi-channel features for the purpose of channel selection. This is achieved by assessing the information conveyed by the features of each channel as a group, using an adaptive group elastic net inducing independent sparsity and temporal smoothness on the DCF solution. The robustness and stability of the learned appearance model are significantly enhanced by the proposed method as the process of channel selection performs implicit spatial regularisation. We use the augmented Lagrangian method to optimise the discriminative filters efficiently. The experimental results obtained on a number of well-known benchmarking datasets demonstrate the effectiveness and stability of the proposed method. A superior performance over the state-of-the-art trackers is achieved using less than $$10\%$$ 10 % deep feature channels.

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JEONG, Kyowon, i Jungwoo LEE. "Channel Parameter Tracking for Adaptive MMSE Channel Estimation in OFDM Systems". IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences E95.A, nr 8 (2012): 1439–43. http://dx.doi.org/10.1587/transfun.e95.a.1439.

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Muradoglu, Metin, i Seckin Gokaltun. "Implicit Multigrid Computations of Buoyant Drops Through Sinusoidal Constrictions". Journal of Applied Mechanics 71, nr 6 (1.11.2004): 857–65. http://dx.doi.org/10.1115/1.1795222.

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Two-dimensional computations of dispersed multiphase flows involving complex geometries are presented. The numerical algorithm is based on the front-tracking method in which one set of governing equations is written for the whole computational domain and different phases are treated as a single fluid with variable material properties. The front-tracking methodology is combined with a newly developed finite volume solver based on dual time-stepping, diagonalized alternating direction implicit multigrid method. The method is first validated for a freely rising drop in a straight channel, and it is then used to compute a freely rising drop in various constricted channels. Interaction of two buoyancy-driven drops in a continuously constricted channel is also presented.

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Jung, Ilchae, Kihyun You, Hyeonwoo Noh, Minsu Cho i Bohyung Han. "Real-Time Object Tracking via Meta-Learning: Efficient Model Adaptation and One-Shot Channel Pruning". Proceedings of the AAAI Conference on Artificial Intelligence 34, nr 07 (3.04.2020): 11205–12. http://dx.doi.org/10.1609/aaai.v34i07.6779.

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We propose a novel meta-learning framework for real-time object tracking with efficient model adaptation and channel pruning. Given an object tracker, our framework learns to fine-tune its model parameters in only a few gradient-descent iterations during tracking while pruning its network channels using the target ground-truth at the first frame. Such a learning problem is formulated as a meta-learning task, where a meta-tracker is trained by updating its meta-parameters for initial weights, learning rates, and pruning masks through carefully designed tracking simulations. The integrated meta-tracker greatly improves tracking performance by accelerating the convergence of online learning and reducing the cost of feature computation. Experimental evaluation on the standard datasets demonstrates its outstanding accuracy and speed compared to the state-of-the-art methods.

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Zhang, Runqing, Chunxiao Fan i Yue Ming. "Learning Enhanced Feature Responses for Visual Object Tracking". Computational Intelligence and Neuroscience 2022 (8.02.2022): 1–15. http://dx.doi.org/10.1155/2022/1241687.

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Visual object tracking is an important topic in computer vision, which has successfully utilized pretrained convolutional neural networks, such as VGG and ResNet. However, the features extracted by these pretrained models are high dimensional, and the redundant feature channels reduce target localization and scale estimation precision, leading to tracking drifting. In this paper, a novel visual object tracking method, called learning enhanced feature responses tracking (LEFRT), is proposed, which adopts the target-specific features to enhance target localization and scale estimation responses. First, a channel attention module, called target-specific network (TSNet), is presented to reduce the redundant feature channels. Secondly, the scale estimation network (SCENet) is introduced to extract spatial structural features to generate a more precise response for the scale estimation. Extensive experiments on six tracking benchmarks, including LaSOT, GOT-10k, TrackingNet, OTB-2013, OTB-2015, and TC-128, demonstrate that the proposed algorithm can effectively improve the precision and speed of visual object tracking. LEFRT achieves 90.4% precision and a 71.2% success rate on the OTB-2015 dataset, improving the tracking methods based on the pretrained features.

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Kulmer, Josef, Erik Leitinger, Stefan Grebien i Klaus Witrisal. "Anchorless Cooperative Tracking Using Multipath Channel Information". IEEE Transactions on Wireless Communications 17, nr 4 (kwiecień 2018): 2262–75. http://dx.doi.org/10.1109/twc.2018.2790936.

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Anderson, Peter A. V. "Tracking and capitalizing on ion channel evolution". Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology 126 (lipiec 2000): S4. http://dx.doi.org/10.1016/s0305-0491(00)80007-3.

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Arikan, F., i O. Arikan. "Adaptive tracking of narrowband HF channel response". Radio Science 38, nr 6 (grudzień 2003): n/a. http://dx.doi.org/10.1029/2003rs002879.

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Srinivasan, S., K. Janse, M. Nilsson i W. Bastiaan Kleijn. "Two-channel speech denoising through minimum tracking". Electronics Letters 46, nr 2 (2010): 177. http://dx.doi.org/10.1049/el.2010.2765.

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Dall'Anese, Emiliano, Seung-Jun Kim i Georgios B. Giannakis. "Channel Gain Map Tracking via Distributed Kriging". IEEE Transactions on Vehicular Technology 60, nr 3 (marzec 2011): 1205–11. http://dx.doi.org/10.1109/tvt.2011.2113195.

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Beinschob, P., M. Lieberei i U. Zölzer. "Improving MIMO-OFDM decision-directed channel estimation by utilizing error-correcting codes". Advances in Radio Science 7 (18.05.2009): 83–88. http://dx.doi.org/10.5194/ars-7-83-2009.

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Abstract. In this paper a decision-directed Multiple-Input Multiple-Output (MIMO) channel tracking algorithm is enhanced to raise the channel estimate accuracy. While DDCE is prone to error propagation the enhancement employs channel decoding in the tracking process. Therefore, a quantized block of symbols is checked on consistency via the channel decoder, possibly corrected and then used. This yields a more robust tracking of the channel in terms of bit error rate and improves the channel estimate under certain conditions. Equalization is performed to prove the feasibility of the obtained channel estimate. Therefore a combined signal consisting of data and pilot symbols is sent. Adaptive filters are applied to exploit correlations in time, frequency and spatial domain. By using good error-correcting coding schemes like Turbo Codes or Low Density Parity Check (LDPC) codes, adequate channel estimates can be acquired even at low signal to noise ratios (SNR). The proposed algorithm among two others is applied for channel estimation and equalization and results are compared.

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Luo, Kaihua, Xiaoping Zhou, Bin Wang, Jifeng Huang i Haichao Liu. "Sparse Bayes Tensor and DOA Tracking Inspired Channel Estimation for V2X Millimeter Wave Massive MIMO System". Sensors 21, nr 12 (10.06.2021): 4021. http://dx.doi.org/10.3390/s21124021.

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Efficient vehicle-to-everything (V2X) communications improve traffic safety, enable autonomous driving, and help to reduce environmental impacts. To achieve these objectives, accurate channel estimation in highly mobile scenarios becomes necessary. However, in the V2X millimeter-wave massive MIMO system, the high mobility of vehicles leads to the rapid time-varying of the wireless channel and results in the existing static channel estimation algorithms no longer applicable. In this paper, we propose a sparse Bayes tensor and DOA tracking inspired channel estimation for V2X millimeter wave massive MIMO system. Specifically, by exploiting the sparse scattering characteristics of the channel, we transform the channel estimation into a sparse recovery problem. In order to reduce the influence of quantization errors, both the receiving and transmitting angle grids should have super-resolution. We obtain the measurement matrix to increase the resolution of the redundant dictionary. Furthermore, we take the low-rank characteristics of the received signals into consideration rather than singly using the traditional sparse prior. Motivated by the sparse Bayes tensor, a direction of arrival (DOA) tracking method is developed to acquire the DOA at the next moment, which equals the sum of the DOA at the previous moment and the offset. The obtained DOA is expected to provide a significant angle information update for tracking fast time-varying vehicular channels. The proposed approach is evaluated over the different speeds of the vehicle scenarios and compared to the other methods. Simulation results validated the theoretical analysis and demonstrate that the proposed solution outperforms a number of state-of-the-art researches.

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Huang, S. H., Jenho Tsao, T. C. Yang i Sheng-Wen Cheng. "Model-Based Signal Subspace Channel Tracking for Correlated Underwater Acoustic Communication Channels". IEEE Journal of Oceanic Engineering 39, nr 2 (kwiecień 2014): 343–56. http://dx.doi.org/10.1109/joe.2013.2251808.

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Bai, Hui, Hong Yu Wang i Shi Huang Shao. "Position Tracking and Attitude Stable Control for an Unmanned Quadrotor Vehicle". Advanced Materials Research 645 (styczeń 2013): 492–96. http://dx.doi.org/10.4028/www.scientific.net/amr.645.492.

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A simplified dynamic model of the quadrotor is established. A multi-channel control scheme based on PID and dynamic inversion is proposed. Four channels are designed to achieve the position tracking and attitude stabilization of the quadrotor. A simulation shows the validity and good features of the control strategy.

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Jwo, Dah Jing, i Meng Hsien Hsieh. "Robustness Enhancement of GPS Vector Tracking Loop Using the Fault Detection and Exclusion Algorithm". Applied Mechanics and Materials 764-765 (maj 2015): 570–74. http://dx.doi.org/10.4028/www.scientific.net/amm.764-765.570.

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Although the vector tracking loop architectures provide several important advantages, they suffer some fundamental drawbacks. The most significant drawback is that failure of tracking in one channel may affect the entire system and lead to loss of lock on all satellites. The other drawback is that errors in the navigation solutions may degrade the accuracy of the tracking results. For robustness improvement of the vector tracking loop, the EKF based receiver autonomous integrity monitoring (RAIM) and fault detection and exclusion (FDE) algorithms are developed to prevent the error of one channel from spreading into the vector tracking loop. The RAIM is used to check the possible fault in the pseudorange and the pseudorange rate; the fault detection and exclusion mechanism is employed for excluding the abnormal satellite signal to prevent the failure of one channel from spreading into the entire tracking loop. The feasibility of the proposed method will be demonstrated. Performance assessment and evaluation for the proposed approach will be carried out.

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Volavy, Jaroslav, Árpád Farkas, Frantisek Lizal, Jakub Elcner i Miroslav Jicha. "Lagrangian tracking of fibres in a channel flow". EPJ Web of Conferences 213 (2019): 02098. http://dx.doi.org/10.1051/epjconf/201921302098.

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Tracking of fibres in a fluid flow is much more complicated than tracking of spherical particles. In fibre motion, the orientation of fibre against the flow direction plays a very important role. In addition to the standard equation of motion, additional equations for orientation and angular velocity must be solved during the tracking of fibres. A mathematical model describing fibre motion is introduced in this work. Capabilities of this model are demonstrated through simulations of fibre transportation by air in a channel flow. The importance of the terms in the equation of angular velocity are discussed.

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Yin, Rui, Xin Zhou, Wei Qi, Celimuge Wu i Yunlong Cai. "Grouping-Based Channel Estimation and Tracking for Millimeter Wave Massive MIMO Systems". Wireless Communications and Mobile Computing 2021 (13.07.2021): 1–14. http://dx.doi.org/10.1155/2021/2922359.

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Although the millimeter wave (mmWave) massive multiple-input and multiple-output (MIMO) system can potentially boost the network capacity for future communications, the pilot overhead of the system in practice will greatly increase, which causes a significant decrease in system performance. In this paper, we propose a novel grouping-based channel estimation and tracking approach to reduce the pilot overhead and computational complexity while improving the estimation accuracy. Specifically, we design a low-complexity iterative channel estimation and tracking algorithm by fully exploiting the sparsity of mmWave massive MIMO channels, where the signal eigenvectors are estimated and tracked based on the received signals at the base station (BS). With the recovered signal eigenvectors, the celebrated multiple-signal classification (MUSIC) algorithm can be employed to estimate the direction of arrival (DoA) angles and the path amplitude for the user terminals (UTs). To improve the estimation accuracy and accelerate the tracking speed, we develop a closed-form solution for updating the step-size in the proposed iterative algorithm. Furthermore, a grouping method is proposed to reduce the number of sharing pilots in the scenario of multiple UTs to shorten the pilot overhead. The computational complexity of the proposed algorithm is analyzed. Simulation results are provided to verify the effectiveness of the proposed schemes in terms of the estimation accuracy, tracking speed, and overhead reduction.

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Yang, Chang-Yi, i Bor-Sen Chen. "Robust MC-CDMA Channel Tracking for Fast Time-Varying Multipath Fading Channel". IEEE Transactions on Vehicular Technology 59, nr 9 (listopad 2010): 4658–64. http://dx.doi.org/10.1109/tvt.2010.2079962.

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Brachet, Anna, Christophe Leterrier, Marie Irondelle, Marie-Pierre Fache, Victor Racine, Jean-Baptiste Sibarita, Daniel Choquet i Bénédicte Dargent. "Ankyrin G restricts ion channel diffusion at the axonal initial segment before the establishment of the diffusion barrier". Journal of Cell Biology 191, nr 2 (18.10.2010): 383–95. http://dx.doi.org/10.1083/jcb.201003042.

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In mammalian neurons, the precise accumulation of sodium channels at the axonal initial segment (AIS) ensures action potential initiation. This accumulation precedes the immobilization of membrane proteins and lipids by a diffusion barrier at the AIS. Using single-particle tracking, we measured the mobility of a chimeric ion channel bearing the ankyrin-binding motif of the Nav1.2 sodium channel. We found that ankyrin G (ankG) limits membrane diffusion of ion channels when coexpressed in neuroblastoma cells. Site-directed mutants with decreased affinity for ankG exhibit increased diffusion speeds. In immature hippocampal neurons, we demonstrated that ion channel immobilization by ankG is regulated by protein kinase CK2 and occurs as soon as ankG accumulates at the AIS of elongating axons. Once the diffusion barrier is formed, ankG is still required to stabilize ion channels. In conclusion, our findings indicate that specific binding to ankG constitutes the initial step for Nav channel immobilization at the AIS membrane and precedes the establishment of the diffusion barrier.

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Bhatia, Himanshu. "Chat Tracking and Monitoring System". International Journal for Research in Applied Science and Engineering Technology 9, nr 9 (30.09.2021): 625–27. http://dx.doi.org/10.22214/ijraset.2021.38040.

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Abstract: With the expanding utilization of instant chat messengers to share data, Suspicious exercises have additionally expanded. There are numerous sources to share the data however moment talk couriers and informal communication sites are fast, simply intended to share anything. In some cases, even new stories are at first separated via online media locales and further on talk couriers rather than any news channel and paper and so forth. Because of these innovation progressions, a few individuals are using these applications inappropriately to share suspicious messages and make arrangements to accomplish something unlawful. With the headway of web innovation and the change in the method of correspondence, it is discovered that much direct news has been examined in Internet discussions well before they are accounted for in conventional broad communications. Additionally, this correspondence channel gives a viable channel to criminal operations, for example, communicating of copyrighted films, compromising messages and internet betting and so on. Our Proposed Framework will examine online plain text messages from chosen conversation gatherings and our framework will choose which post is legitimate and unlawful. It will detect the suspicious keyword from the chatting and give a warning message to the user and also a mail will be sent to admin which will include all the details of the user. Keywords: Suspicious Chat, Chat Monitoring, Abusive word, Terrorist activities, Chat Tracking.

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Ali, H. "CP-Based SBHT-RLS Algorithms for Tracking Channel Estimates in Multicarrier Modulation Systems". Journal of Electrical and Computer Engineering 2012 (2012): 1–12. http://dx.doi.org/10.1155/2012/452806.

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Cyclic prefix (CP) in multicarrier modulation systems has been considered as an alternative to the training sequences to track channel estimates. In this paper, two new algorithms are developed that exploit CP from their data detection part and employ systolic block Householder transformation recursive least squares (SBHT-RLS) algorithms for channel tracking in multicarrier systems. The new methods are compared with the existing CP exploiting correlation matrix based block RLS (CMB-RLS) channel tracking approach to outline their relative advantages. Aspects of computational complexity and parallel implementation are addressed, and the algorithms are tested in terms of their channel estimation and tracking capabilities. Performance of the algorithms is also evaluated for varying forgetting factor parameter values, constellation size, and word lengths. Floating-point and fixed-point simulations are tailored to illustrate pertinent tradeoffs.

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Oleárová, Mária, Radovan Bačík i Richard Fedorko. "Generational Differences of Consumers: A Study of Preferred Purchasing Channels". 12th GLOBAL CONFERENCE ON BUSINESS AND SOCIAL SCIENCES 12, nr 1 (8.10.2021): 132. http://dx.doi.org/10.35609/gcbssproceeding.2021.12(132).

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The development of the Internet and current technologies have contributed to significant progress in the consumer purchasing process. Nowadays, the decision is much easier and more intuitive. Companies are focusing on tracking the shopping path of customers who are exposed meet companies through many different channels and contact points, both online and offline (Baxendale et al. 2015). This means that consumers are not limited to online or offline channels, they obtain information from both sources. In the age of the Internet and the rapid development of technology, the purchasing process is becoming increasingly fragmented, blurring the boundaries between online and offline channels. The integration of these channels is therefore becoming key to ensuring a smooth and convenient purchasing process (Piotrowicz and Cuthbertson 2014). Given this fact, our goal was to examine which purchasing channels (single-channel or cross-channel) Slovak consumers prefer. This study focused on identifying differences between consumers in terms of generations X, Y and Z. Keywords: Consumer Behaviour, Shopping, Cross-Channel, Showrooming, Webrooming

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