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- ItemShort-Term Entropy of Signal Energy Used for Effective Detecting of Weak Gunshots in Noisy Environments(MDPI, 2024-07-30) Sigmund, MilanConventional gunshot detection systems can quickly and reliably detect gunshots in the area where the acoustic sensors are placed. This paper presents the detection of weak hunting gunshots using the short-term entropy of signal energy computed from acoustic signals in an open natural environment. Our research in this field was primarily aimed at detecting gunshots fired at close range with the usual acoustic intensity to protect wild elephants from poachers. The detection of weak gunshots can extend existing detection systems to detect more distant gunshots. The developed algorithm was optimized for the detection of gunshots in two categories of the surrounding sounds, short impulsive events and continuous noise, and tested in acoustic scenes where the power ratios between the weak gunshots and louder surroundings range from 0 dB to -14 dB. The overall accuracy was evaluated in terms of recall and precision. Depending on impulsive or noise sounds, binary detection was successful down to -8 dB or -6 dB; then, the efficiency decreases, but some very weak gunshots can still be detected at -13 dB. Experiments show that the proposed method has the potential to improve the efficiency and reliability of gunshot detection systems.
- ItemSpectral–Spatial Transformer-based Semantic Segmentation for Large-scale Mapping of Individual Date Palm Trees using Very High-resolution Satellite Data(Elsevier, 2024-05-08) Al-Ruzouq, Rami; Gibril, Mohamed Barakat A.; Shanableh, Abdallah; Bolcek, Jan; Lamghari, Fouad; Hammour, Nezar Atalla; Al-Keblawy, Ali; Jena, RatiranjanDate palm plantations in the United Arab Emirates (UAE) are under threat from soil salinity, drought, and date palm weevils. Accordingly, monitoring and conserving date palms are crucial to preserving a vital component of the country’s agricultural heritage, economy, food security, and ecological balance. Previous studies have effectively identified date palm trees using RGB-based aerial and UAV imagery utilizing diverse deep learning methods. However, the utilization of very high-resolution satellite data for delineating individual date palm crowns remains unexplored due to the limited spatial resolution capabilities of existing satellite systems. This study primarily aimed to achieve precise and comprehensive mapping of date palm trees using WorldView-3 (WV-3) satellite data by leveraging the high representational power of the state-of-the-art vision transformers (ViT) in capturing global information from the input data. First, an in-depth analysis assessment of the various transformer-based semantic segmentation architectures, including UperNet with vision transformer and Swin transformer, SegFormer, Mask2Former, and UniFormer, was conducted. Second, the integration of spectral data on the performance of ViTs was evaluated. Moreover, the models’ generalizability and complexity effect on the segmentation effectiveness were assessed. Accordingly, a postprocessing strategy was developed to aid in delineating and counting date palm trees from semantic segmentation outputs. Results demonstrated that integration of WV-3 spectral data into the analysis resulted in a marked improvement in segmentation quality. The UniFormer, UperNet-Swin, and Mask2Former models demonstrated considerable improvements in multispectral data analysis, with increases in mean intersection over union (mIoU) of 2.17% (77.88% mIoU, 86.01% mean F-score [mF-score]), 2% (78.10% mIoU, 86.18% mF-score), and 1.15% (77.36% mIoU, 85.59% mF-score), respectively, compared with their RGB-based results. Evaluations of model transferability also indicated that Mask2Former, UniFormer, and UperNet-Swin transformers efficiently adapted to multispectral data in the Dibba region. These models achieved mIoU scores of 84.36%, 84.25%, and 83.17% and mF-scores of 90.95%, 90.87%, and 90.13%, highlighting their effectiveness and potential for broader regional application. This research highlights the efficacy and feasibility of using ViTs with WV-3 multispectral data for accurate and comprehensive surveying of date palm plantations, enabling the development of palm tree inventories and continuously updating geospatial databases.
- ItemVoltage Differencing Current Conveyor Differential Input Transconductance Amplifier: Novel Active Element and Its Resistorless Filtering Application(IEEE, 2019-10-30) Šotner, Roman; Jeřábek, Jan; Langhammer, Lukáš; Petržela, Jiří; Jaikla, Winai; Tuntrakool, SuntiThis paper introduces novel modification of active element based on current conveyor transconductance amplifier core abbreviated as current controlled voltage differencing current conveyor differential input transconductance amplifier (CC-VDCCDITA). The active element is implemented by recently developed and manufactured IC modular device based on I3T25 0.35 um ON Semiconductor CMOS process. Active element uses three internal active cells of this IC device for construction of the CC-VDCCDITA. An application example of proposed element in simple special resistor-less electronically adjustable biquadratic filter is shown. Brief comparison with state-of-the-art solutions indicates beneficial features of proposed solution. Simulation results in Cadence IC tool accompany precise laboratory experimental measurements with real prototype.
- ItemNanoelectronic COupled problems solutions - nanoCOPS: modelling, multirate, model order reduction, uncertainty quantification, fast fault simulation(2016-07-14) ter Maten, E Jan W; Putek, Piotr; Gunther, Michael; Pulch, Roland; Tischendorf, Caren; Strohm, Christian; Schoenmaker, Wim; Meuris, Peter; De Smedt, Bart; Benner, Peter; Feng, Lihong; Banagaaya, Nicodemus; Yue, Yao; Janssen, Rick; J Dohmen, Jos; Tasić, Bratislav; Deleu, Frederik; Gillon, Renaud; Wieers, Aarnout; Brachtendorf, Hans-Georg; Bittner, Kai; Kratochvíl, Tomáš; Petržela, Jiří; Šotner, Roman; Götthans, Tomáš; Dřínovský, Jiří; Schöps, Sebastian; J Duque Guerra, David; Casper, Thorben; De Gersem, Herbert; Römer, Ulrich; Reynier, Pascal; Barroul, Patrice; Masliah, Denis; Rousseau, BenoîtThe FP7 project nanoCOPS derives new methods for simulation during development of designs of integrated products. It covers advanced simulation techniques for electromagnetics with feedback couplings to electronic circuits, heat and stress. It is inspired by interest from semiconductor industry and by a simulation tool vendor in electronic design automation. The project is on-going and the paper presents the outcomes achieved after the first half of the project duration.
- ItemElectronically Reconfigurable Universal Filter Based on VDTAs(IEEE, 2018-04-19) Langhammer, Lukáš; Šotner, Roman; Domanský, Ondřej; Hricko, TomášThe proposed filter extends features of the previously presented Voltage Differencing Transconductance Amplifiers (VDTAs)-based frequency filter. It brings the new advantage of an electronic reconfiguration of its transfer. The proposed structure provides reconnection-less change between low-pass, band-pass, high-pass, band-stop and all-pass transfer functions. The electronic control of the filter parameters such as the pole frequency and quality factor remain preserved. The theoretical assumptions are supported by PSpice simulations using transistor-level models.