Search

Summary: New cognitive radio (CR) systems require high throughput and bandwidth. Hence, CR users need to detect wide frequency bands of the radio spectrum to exploit unused frequency channels. This paper proposes a new wideband spectrum sensing (WBSS) detection approach based on machine learning (ML) for scanning subchannels. The originality of the proposed approach is to detect spectrum opportunities using a narrowband spectrum sensing (NBSS) method‐based support vector machine (SVM) classification and two features: energy and goodness of fit (GoF). The simulation results show that the proposed WBSS approach‐based ML presents a higher probability of detection than the WBSS approach‐based conventional detectors, even at low signal‐to‐noise ratio (SNR). Finally, the software defined radio (SDR) implementation validates the proposed WBSS approach for real detection scenarios. [ABSTRACT FROM AUTHOR]

Recent discoveries of sex chromosome diversity across the tree of life have challenged the canonical model of conserved sex chromosome evolution and evoked new theories on labile sex chromosomes that maintain less differentiation and undergo frequent turnover. However, theories of labile sex chromosome evolution lack direct empirical support due to the paucity of case studies demonstrating ongoing sex chromosome turnover in nature. Two divergent lineages (viz. WL & EL) of nine-spined sticklebacks (Pungitius pungitius) with different sex chromosomes (linkage group [LG] 12 in the EL, unknown in the WL) hybridize in a natural secondary contact zone in the Baltic Sea, providing an opportunity to study ongoing turnover between coexisting sex chromosomes. In this study, we first identify an 80 kbp genomic region on LG3 as the sex-determining region (SDR) using whole-genome resequencing data of family crosses of a WL population. We then verify this region as the SDR in most other WL populations and demonstrate a potentially ongoing sex chromosome turnover in admixed marine populations where the evolutionarily younger and homomorphic LG3 sex chromosome replaces the older and heteromorphic LG12 sex chromosome. The results provide a rare glimpse of sex chromosome turnover in the wild and indicate the possible existence of additional yet undiscovered sex chromosome diversity in Pungitius sticklebacks. [ABSTRACT FROM AUTHOR]

This study introduces a reconfigurable and agile RF front-end (RFFE) architecture that significantly enhances the performance of software-defined radios (SDRs) by seamlessly adjusting to varying signal requirements, frequencies, and protocols. This flexibility greatly enhances spectrum utilization, signal integrity, and overall system efficiency—critical factors in aviation, where reliable communication, navigation, and surveillance systems are vital for safety. A versatile RF front-end is thus indispensable, enhancing connectivity and safety standards. We explore the integration of this flexible RF front-end in SDRs, focusing on the detailed design of essential components, such as receivers, transmitters, RF switches, combiners, and splitters, and their corresponding RF pathways. Comprehensive performance evaluations confirm the architecture's reliability and functionality, including an extensive analysis of receiver gain, linearity, and two-tone test results. These assessments validate the architecture's suitability for aviation radios and address considerations of size, weight, and power-cost (SWaP-C), demonstrating significant gains in operational efficiency and cost-effectiveness. The introduction of the new RF front-end on a single SDR board not only substantially reduces size and weight but also adds up to 18 dB gain to the received signal. It also allows for a high level of design flexibility, enabling seamless software transitions between different radios and the capacity to manage three times more radios with the same hardware, thereby significantly boosting the system's ability to handle multiple radio channels efficiently. [ABSTRACT FROM AUTHOR]

Abstract This study aimed to test the load to fracture of flowable and high viscosity bulk-fill composites compared to a convetional (packable) composite used to build up pulpless teeth. 45 endodontically treated premolars were restored with fiber posts then divided into three groups (N = 15) according to the core build-up material. SDR group: (Smart Dentine Replacement), (BF): Filtek One Bulk Fill and (CC) Filtek Z350 packable composite. After core build up the teeth received full coverage crowns. Load to fracture (Newton) was recorded for each specimen. One-way ANOVA and Tukey multiple comparisons test were used. The highest load at fracture was shown by (CC) group (1067 N), followed by (BF) group (879 N), and the SDR group (838 N). One way ANOVA and Tukey’s multiple comparisons test demonstrated no significant differences between CC, SDR, and BF groups (p > 0.05). The three materials showed comparable load to fracture. Further studies with simulation to occlusal forces and oral temperature are required.

In this paper, an SDR-based single-carrier, simplex, wireless communication system is presented for Internet-of-Things (IOT) applications. The research work includes the design of both hardware and software such that the system can communicate reliably over a distance of 100 meters. The hardware component of this work includes the complete design and fabrication of the transmitter and receiver front-end PCBs. On the other hand, the software aspect which consists of signal processing is implemented on a software-defined radio where various impairment correction techniques are implemented to mitigate challenges in the wireless channel such as carrier frequency offset, phase offset, and timing offset. Furthermore, an equalization algorithm is implemented to compensate for errors that arise due to the phenomena of multipath fading. To demonstrate the efficacy of the proposed communication system in an indoor environment, an extensive validation test scheme was devised and performed. The proposed communication system demonstrates an optimum spectral efficiency of 3.2 bps/Hz at a bit rate of 26.66 Mbit/s.

This article presents a fresh perspective on the Triffin Paradox, a concept introduced by economist Robert Triffin in the mid-20th century that continues to have a significant impact on global financial systems and policies. Despite the passage of time and the evolution of the economy, the fundamental principles of the Triffin Paradox remain relevant in today's financial discussions. The paper provides a thorough analysis of the ongoing relevance of the Triffin Paradox in the modern global economy. It draws upon historical context, theoretical frameworks, and empirical evidence to shed light on how the paradox continues to manifest itself in the current financial landscape. Specifically, it explores how the dominance of the U.S. dollar as the world's primary reserve currency perpetuates structural imbalances and systemic vulnerabilities, echoing the concerns raised by Triffin. Moreover, the paper delves into the implications of the Triffin Paradox for various stakeholders, including policymakers and central banks. It examines the challenges posed by the pursuit of domestic monetary policy objectives in an interconnected world, where the stability of the global financial system relies heavily on the stability of the reserve currency issuer. Additionally, the paper explores potential strategies for mitigating the risks associated with the Triffin Paradox and fostering a more sustainable international monetary order. By integrating insights from economics, finance, and international relations, this paper contributes to a deeper understanding of the Triffin Paradox and its enduring significance in shaping contemporary financial dynamics. It emphasizes the need for policymakers and stakeholders to address the inherent structural tensions in the global monetary system, with the goal of promoting financial stability, economic resilience, and inclusive prosperity worldwide.

This paper explores the potential of an Integrated Sensing and Communication (ISAC) system to enhance search-and-rescue operations. While prior research has explored ISAC capabilities in Unmanned Aerial Vehicles (UAVs), our study focuses on addressing the specific challenges posed by modern communication standards (e.g., power, frequency, and bandwidth limitations) in the context of search-and-rescue missions. The paper details effective methods for processing echoed signals generated by downlink transmissions and evaluates key performance indicators, including Noise Equivalent Sigma Zero (NESZ) and channel capacity. Additionally, we utilize synchronization uplink signals transmitted by User Equipment (UE) to improve target detection and classification of possible victims by fusing SAR imagery with triangulation results from uplink signals. An experimental campaign validates the proposed setup by integrating SAR images of the environment with active localization results, both produced by a UAV equipped with a Software Defined Radio (SDR) payload. Our results demonstrate the system's capability to detect and localize buried targets in avalanche scenarios, with localization errors ranging from centimeters to 10 m depending on environmental conditions. This successful integration highlights the practical applicability of our approach in challenging search-and-rescue missions. [ABSTRACT FROM AUTHOR]

Fifth-generation (5G) mobile networks offer flexibility to address various emerging use cases. Radio virtualization enhances flexibility by enabling multiple heterogeneous virtual radios to coexist on the same hardware. One method for virtualizing radio devices involves using virtual machines and containers to multiplex software radio implementations over generic multipurpose radio hardware. This paper reviews security issues in this context, evaluates the experimental bounds of communication for software-defined radio (SDR) devices, and assesses virtualization's impact on radio virtualization's performance. This study aims to determine the suitability of virtual environments for SDR applications. The results indicate that container-based radio virtualization performance is comparable to SDR applications running on native Linux. [ABSTRACT FROM AUTHOR]

This work presents the development and testing of an experimental web-based SDR (software-defined radio) monitoring system for indirect solar activity detection, which has the ability to estimate and potentially predict various events in space and on earth, including solar flares, coronal mass ejections, and geomagnetic storms. The proposed system can be used to investigate the effect of solar activity on the propagation of very-low-frequency (VLF) signals. The advantages and benefits of the given approach are as follows: increasing measurement accuracy and eventual solar activity identification by combining measurements from multiple spatially distributed SDRs. The verification process involves carrying out several experiments comparing data from the GOES satellite system and the Dunksin SuperSID system with information received by the SDR monitoring system. Then, utilizing Pearson correlation coefficients, the measured data from the SDRs, along with those from the GOES satellite system and the Dunsing monitoring station, are investigated. At the time of a solar flare, the correlation value is above 90% for most of the stations used. Combining the signal-to-noise ratio via summation also shows an improvement in the results, with a correlation above 98%. [ABSTRACT FROM AUTHOR]

At present, the use of time-domain deep learning for end-to-end neural network models has the problem of long training time and poor performance in music source separation. To address this issue, a U-network squeezing excitation bidirectional simple recursive unit model was proposed based on the deep extractor model. Replace Unet SE Bisru with Unet SE Bisru in the following text. This model improves the bidirectional long short-term memory network into a bidirectional simple recurrent unit, and then introduces attention mechanisms in the generalized encoding and decoding layers. The squeezing excitation block is used to selectively extract features based on the type of audio to be separated. Finally, group normalization is added after onedimensional convolution, And its effectiveness was verified. The experimental results show that the signal noise distortion ratio in the improved model is 5.68 decibels compared to the bidirectional simple recursive unit value, which is higher than the 5.55 decibels of bidirectional long short-term memory. After adding the squeezing excitation module, the overall increase is about 0.1-0.5 decibels. In addition, in the model comparison, the three indicators of the improved model with the same number of channels were 5.68 decibels, 5.91 decibels, and 11.28 decibels, respectively, higher than the benchmark model. Compared with other music source classification models, the improved model has better comprehensive separation performance. Although some indicators are lower than the comparison model, the signal noise distortion ratio of drum and bass is 6.11 decibels and 6.36 decibels, which is better than the comparison model. Overall, the improved model has high performance in music source separation for music signal processing and can be effectively applied in practical music source separation. [ABSTRACT FROM AUTHOR]

For effective water and land resource management in data-scarce areas, it is imperative to investigate the spatial variability of sediment yield using a rapid, reliable, and affordable approach. The current study demonstrated the use of tools and models viz. Geographic Information System (GIS), Revised Universal Soil Loss Equation (RUSLE), and Sediment Delivery Ratio (SDR) based approach for the assessment of soil loss and sediment yield rate in Lake Hawassa Sub-basin. Input data used were soil, rainfall, digital elevation model (DEM), and land use and land cover change (LULC) maps. The result of the study showed that there was significant and widespread soil loss and sediment yield on cultivated land dominated by moderate, steep and very steep slopes with little vegetation and barren areas. An estimated mean of 16.36 t/ha/year, or 1.97 million tonnes of soil is lost annually by sheet and rill erosion across the Sub-basin. The sediment delivery ratio (SDR) at the outlet of the lake sub-basin was 0.249. Accordingly, the quantified sediment yield at the sub-basin outlet, taking into account the average-based soil loss and sediment delivery ratio, was found to be 4.07 t/ha/year. The annual siltation rate of the lake from these two forms of erosion was found to be 1.01 cm/year. Therefore, depending on the severity of the soil loss, appropriate Best Management Practices (BMP) should be applied to reduce the rate of soil loss and sediment yield to protect the lake and its ecosystem. [ABSTRACT FROM AUTHOR]

The paper considers the design of sparse arrays in the interference active environment to minimise the system complexity and achieve reduced hardware cost. For this, we propose a sparse array design methodology to attain maximum signal-to-interference plus noise ratio (MaxSINR) in the presence of interfering signals. We formulate the optimisation problem as a real-valued quadratically constrained quadratic program (QCQP) with the non-convex $\textstyle\ell_p$ ℓ p norm to promote sparsity, which is iteratively controlled in the proposed approach. We employ the semidefinite relaxation (SDR) technique and the principle of the majorization-minimisation (MM) algorithm to solve the non-convex QCQP problem. The efficacy of the proposed algorithm is demonstrated through the simulation results. The sparse array obtained through the proposed method performs well when compared with the reweighted $\textstyle\ell_1$ ℓ 1 algorithm. [ABSTRACT FROM AUTHOR]

This paper empirically examines the role of USD, EUR, and CNY as international payment currencies in Korea, China, and Japan. Our survey of business people in those countries finds that higher convertibility and stability of these currencies in the SDR enhance their acceptability and usability for international payments. However, even during times of instability, USD remains highly accepted and usable as a trade payment currency unlike the cases of EUR and CNY. Therefore, maintaining exchange rate stability is essential for improving the acceptability and usability of EUR and CNY as international payment currencies. [ABSTRACT FROM AUTHOR]

Abstract The primary objective of this research is to propose and examine a technique for accurately determining the azimuth angle of cooperative objects. The proposed methodology aims were to achieve fast processing, increased precision, and enhanced safety. A transmitter emitting a continuous wave with a hopping frequency was utilized in combination with interferometry techniques to measure the angle of arrival (AOA) between two antennas. The efficient method incorporates a coarse-to-fine strategy that improves processing speed and azimuth angle accuracy and to effectively eliminate any signal interference, a Fourier bandpass filter is utilized. The coarse estimation is performed using the fast Fourier transform (FFT) algorithm, while the fine estimation is achieved using the multiple signal classification (MUSIC) algorithm. The fine estimation involves utilizing coarse angle input and a scan limit of 2.5° that is determined from the largest simulated root mean square error (RMSE) value. Modelling and outdoor testing using software defined radio (SDR) have been carried out to assess the proposed methodology. The results from the analysis indicate that the proposed method produces the desired RMSE estimation of less than 1°, thereby validating its accuracy and effectiveness.

In our pursuit of high-power terahertz (THz) wave generation, we propose innovative edge-terminated single-drift region (SDR) multi-quantum well (MQW) impact avalanche transit time (IMPATT) structures based on the AlxGa1−xN/GaN/AlxGa1−xN material system, with a fixed aluminum mole fraction of x = 0.3. Two distinct MQW diode configurations, namely p+-n junction-based and Schottky barrier diode structures, were investigated for their THz potential. To enhance reverse breakdown characteristics, we propose employing mesa etching and nitrogen ion implantation for edge termination, mitigating issues related to premature and soft breakdown. The THz performance is comprehensively evaluated through steady-state and high-frequency characterizations using a self-consistent quantum drift-diffusion (SCQDD) model. Our proposed Al0.3Ga0.7N/GaN/Al0.3Ga0.7N MQW diodes, as well as GaN-based single-drift region (SDR) and 3C-SiC/Si/3C-SiC MQW-based double-drift region (DDR) IMPATT diodes, are simulated. The Schottky barrier in the proposed diodes significantly reduces device series resistance, enhancing peak continuous wave power output to approximately 300 mW and DC to THz conversion efficiency to nearly 13% at 1.0 THz. Noise performance analysis reveals that MQW structures within the avalanche zone mitigate noise and improve overall performance. Benchmarking against state-of-the-art THz sources establishes the superiority of our proposed THz sources, highlighting their potential for advancing THz technology and its applications. [ABSTRACT FROM AUTHOR]

UAV communications have seen a rapid rise in the last few years. The drone class of UAV has particularly become more widespread around the world, and illicit behavior using drones has become a problem. Therefore, localization, tracking, and even taking control of drones have also gained interest. Knowing the frequency of a target signal, its position can be determined (as the angle of arrival with respect to a fixed receiver point) using radio frequency-based localization techniques. One such technique is represented by the subspace-based algorithms that offer highly accurate results. This paper presents the implementation of the MUSIC algorithm on an SDR-based system using a uniform circular antenna array and its experimental evaluation in relevant outdoor environments for drone localization. The results show the capability of the system to indicate the AoA of the target signal. The results are compared with the actual direction computed from the log files of the drone application and validated with a professional direction-finding solution (i.e., Narda SignalShark equipped with the automatic direction-finding antenna). [ABSTRACT FROM AUTHOR]

The topic of radio direction finding is quite broad and complex, as it has applications in many areas of life, from domestic to industrial. Despite the large number of possible systems and their purposes, there are accessible solutions which allow starting research in this field of radio engineering and signal processing and can also serve as a basis for further development of specialized systems. One of such solutions is SDR transceivers and receivers. Software-defined radio is a radio-electronic device that contains all the necessary components for digitizing received signals (in case of receivers) and reproducing a specified signal (transmission, in case of transceivers). Structurally, these devices contain a heterodyne for signal shifting in the frequency range, as well as ADC/DAC for reception and transmission, respectively. This work implements a system for determining the direction to the source of a FM radio signal based on a dual-channel SDR receiver and a personal computer. Direction finding is performed using the MUSiC algorithm. GNU Radio and Matlab software solutions are used for signal processing. Both programs are widely used in digital signal processing. The GNU Radio is unique because of its graphical block editor that is used for signal reception, processing, storage, and transmission. Matlab is known for its versatility and is used in many areas besides radio technology. It’s use in this work is justified by its convenient handling of matrices, and therefore the MUSiC algorithm was presented in detail and implemented accordingly. The MUSiC algorithm belongs to methods for estimating directions to the source of radio emissions by maximizing the spatial power spectrum of the received signal. The advantage of the MUSiC algorithm over other popular DOA (direction of arrival) estimation methods is its effectiveness even in negative signal-to-noise ratios. The result of the research on the implemented setup is the determination of the azimuth to the radio tower in urban conditions. The research was carried out by analyzing the signal from an FM radio station at a frequency of 100.6 MHz. The error in determining the direction to the radio signal source was 6 degrees. [ABSTRACT FROM AUTHOR]

In the present work, four parametric combinations of LS and P factor have been adopted for assessment of RUSLE-based soil erosion in Bamnidhi subbasin of the upper Mahanadi basin. The basin was discretized of the basin into 98 grids where by applying the SEdiment Delivery Distributed (SEDD) model, total sediment yield from the catchment is computed as sum of the yields from each grid. Soil erosion maps generated are classified as low, moderate, and severe concerning soil erosion potential as < 5, 5–30, and > 30 t ha−1 year−1 respectively. It was observed that the percentage disagreement of erosion area for the three classes with 37%, 25% and 12% for combinations 1 and 4, whereas for combinations 2 and 3 the disagreement improves to 44%, 26%, and 18% respectively. Validation of the maps with satellite information-based FCC showed 75% of accuracy to identify points in moderate to severe zone. For development of MLR model to assess soil erosion, the best parameter set has been selected with ${R^2} = 0.75$ R 2 = 0.75 and slope is found to be the most influential factor for soil loss than LULC, rainfall, and soil type. [ABSTRACT FROM AUTHOR]

Next-generation wireless systems require increased spectral and energy efficiency in terminals. This can only be achieved if the nonlinear characteristics of the radio front-end, primarily the power amplifier (PA), are known and considered while designing algorithms or optimizing radio links. PA datasheets contain limited information, and wideband PA measurements typically require advanced equipment and software. This paper proposes a measurement and signal processing framework that enables the acquisition of nonlinear PA characteristics using generic complex sample transmitters and receivers, e.g., software-defined radio (SDR). This paper also proposes a multistage signal calibration and synchronization procedure that allows obtaining nonlinear PA characteristics that are non-distorted by other phenomena. The correctness and usefulness of the proposed framework are demonstrated by measuring three PAs, each under varying supply voltage and carrier frequency. At the same time, the high variability of the obtained nonlinear characteristic justifies the need for PA measurements to obtain awareness of nonlinear characteristics. [ABSTRACT FROM AUTHOR]

Erosion is the loss or erosion of land or parts of land from a place by water or wind. Erosion causes the loss of fertile soil layers good for plant growth and reduces the soil's ability to absorb and retain water. The Liliba watershed area in Kupang City includes Maulafa District, Oebobo District, and Kelapa Lima District. The Liliba River Watershed (DAS) is part of the development of the Noelmina River area, which flows into Oesapa Beach. The Liliba watershed has an area of 4,534 hectares with a central river length of 20,176.22 m. Using the USLE Method and SDR Transport Analysis, it was found that the erosion that occurred was 3.72 tonnes per year, and the amount of sediment transport that occurred was 2.73 tonnes per year. [ABSTRACT FROM AUTHOR]

Railway communication is undergoing a transitional period worldwide, and 5G for railway (5G-R), which has been adopted by the Railway International Union (UIC) in China and in many other countries, which is a common concern all over the world. The 2100 MHz frequency band, which ranks among the top three mainstream frequency bands for public 5G network deployment globally, has recently been issued by MIIT for a 5G-R trial in China, and the frequency is fairly close to 5G-R frequency band of 1900 MHz in Europe. Propagation study for railway communication, especially for mainline, which is the most common and widely used scenario, is of great importance, because it is closely related to passengers' lives and properties. In this article, based on the 5G-R dedicated network testing environment constructed along the test line of loop railway of National Railway Track Test Center of China, the 2100 MHz 5G-R propagation measurement campaign is conducted, with an in-service SS-RSRP signal-based passive 2100 MHz large-scale channel testing system, as well as a SDR-based 2100 MHz 5G-R channel sounding system, based on which the large-scale as well as small-scale channel characteristics are derived and extensively analyzed. With data derived from the passive testing system, the classical FI, CI as well as TR 38.901 large-scale channel models are properly fitted and compared by calculating RMSE as well as MAE values. Moreover, based on the SDR-based channel sounding system, conclusions on the relationship between the parameters of multi-path component numbers, RMS time spread, received power and distance between the transmitter and the receiver are drawn. The 5G-R system studied in this letter is symmetric FDD communication system, apart from the 2 aspects of channel modeling characteristics, which are large-scale and small-scale complementing each other, the research methodology adopted of the letter also has two aspects, passive measurement, as well as active measurement, and both methods have their own advantages and different focuses, which can also complements each other. Relevant research results of this letter will be helpful for facilitating the R&D, deployment, as well as network optimization of a future mobile communication system under railway mainline scenario. [ABSTRACT FROM AUTHOR]

Abstract—The study of molecular and genetic mechanisms of sex determination in the poplar is of interest not only in the fundamental science, but also in the applied research. In landscaping of large settlements, it is advisable to use male individuals of the Populus genus due to their hypoallergenicity and increased resistance to environmental pollution, stress conditions, and pathogens. However, sex determination in poplars is complicated by the complex genetic structure of the sex-determining region of the genome (SDR). In this review, the emergence, evolution, structure, and function of the SDR in the genus Populus are discussed. Current insights into the structure and function of the key regulator of sex selection in poplars, orthologue of the ARR16/ARR17 gene and the possible roles of other genes that are differentially expressed between male and female plants, including microRNAs, in this process are discussed in detail. The great diversity of species and the high complexity of SDR organization justify the need for further study of the molecular mechanisms of sex determination in poplars. [ABSTRACT FROM AUTHOR]

Wearable devices, such as headsets and activity trackers, rely heavily on the Bluetooth and/or the Bluetooth Low Energy wireless communication standard to exchange data with smartphones or other peripherals. Since these devices collect personal health and activity data, ensuring the privacy and security of the transmitted data is crucial. Therefore, we present a dataset that captures complete Bluetooth communications—including advertising, connection, data exchange, and disconnection—in an RF isolated environment using software-defined radio. We were able to successfully decode the captured Bluetooth packets using existing tools. This dataset provides researchers with the ability to fully analyze Bluetooth traffic and gain insight into communication patterns and potential security vulnerabilities. Dataset: https://pubfaili.edi.lv/wearsecdataDataset License: CC-BY-SA [ABSTRACT FROM AUTHOR]

Implementing an RF scanner-type anti-drone system requires an expensive broadband receiver that collects real-time broadband drone RF signals, which change rapidly over time. In this study, we implemented a system that can monitor the spectrogram image of a wideband drone radio signal in real time using low-cost narrowband SDR equipment instead of an expensive wideband receiver. The implemented system, comprising three Adalm Pluto SDRs running in python, can monitor the spectrogram of drone RF signals in the entire 2.4 GHz ISM frequency band in real time in a typical PC environment. The performance of the implemented system was verified by measuring the RF signals generated by four types of commercial drones in an electromagnetic anechoic chamber. Combining the implemented receiver with an AI engine based on python provides the possibility of implementing a real-time anti-drone system at a low cost. [ABSTRACT FROM AUTHOR]

We propose a novel single channel speech enhancement algorithm using iterative constrained Non-negative matrix factorization (NMF) based adaptive Wiener gain for non-stationary noise. In the recent past, NMF-based Wiener filtering methods were used for speech enhancement. The Wiener filter performance depends on the adaptive gain factor value. The adaptive gain factor (α ) value is constant regardless of noise type and signal to noise ratio (SNR), so it will affect speech enhancement performance. To overcome this, the adaptive factor value is calculated using a genetic algorithm (GA). Here, the GA adjusts the adaptive Wiener gain based on noise type and SNR level. The GA-based adaptive Wiener gain minimizes Wiener filter estimation errors and improves speech quality by adjusting the base vector weights of noise and speech. Additionally, we use the iterative constraints NMF (IC-NMF) method for calculating the priors from noisy speech magnitudes. We select the Erlang, Inverse Gamma, Students-t, and Inverse Nakagami distributions for speech priors and Gaussian distributions for noise priors. Noise and speech samples are well correlated with those distributions. This provides accurate estimation of the necessary statistics of these distributions to regularize the NMF criterion. So, we combine an iterative constrained NMF and a genetic algorithm-based adaptive Wiener filtering method for speech enhancement. The proposed method outperforms other benchmark algorithms in terms of source to distortion ratio (SDR), short-time objective intelligibility (STOI), and perceptual evaluation of speech quality (PESQ). [ABSTRACT FROM AUTHOR]

Key message: Unreduced megagametophytes via second-division restitution were confirmed through heterozygosity analysis, and four candidate physical centromeres of rubber were located for the first time. The evaluation of maternal heterozygosity restitution (MHR) is vital in identifying the mechanism of 2n gametogenesis and assessing the utilization value of 2n gametes. In this study, three full-sib triploid populations were employed to evaluate the MHR of 2n female gametes of rubber tree clone GT1 and to confirm their genetic derivation. The 2n female gametes of GT1 were derived from second-division restitution (SDR) and transmitted more than half of the parental heterozygosity. In addition, low recombination frequency markers were developed, and four candidate physical centromeres of rubber tree were located for the first time. The confirmation that 2n female gametes of rubber tree clone GT1 are derived from SDR provides insights into the molecular mechanisms of 2n gametogenesis. In addition, the identified centromere location will aid in the development of centromeric markers for the rapid identification of the 2n gametogenesis mechanism. [ABSTRACT FROM AUTHOR]

This study examined the implementation of rate-splitting multiple access (RSMA) in a multiple-input single-output system using simultaneous wireless information and power transfer (SWIPT) technology. The coexistence of a base station and a power beacon was considered, aiming to transmit information and energy to two sets of users. One set comprises users who solely harvest energy, whereas the other can decode information and energy using a power-splitting (PS) structure. The main objective of this optimization was to minimize the total transmit power of the system while satisfying the rate requirements for PS users and ensuring minimum energy harvesting (EH) for both PS and EH users. The non-convex problem was addressed by dividing it into two subproblems. The first subproblem was solved using a deep learning-based scheme, combining principal component analysis and a deep neural network. The semidefinite relaxation method was used to solve the second subproblem. The proposed method offers lower computational complexity compared to traditional iterative-based approaches. The simulation results demonstrate the superior performance of the proposed scheme compared to traditional methods such as non-orthogonal multiple access and space-division multiple access. Furthermore, the ability of the proposed method to generalize was validated by assessing its effectiveness across several challenging scenarios. [ABSTRACT FROM AUTHOR]

Cassava is one of the most important commodities worldwide, serving as a crucial food source due to its rich content of nutrients such as carbohydrates, protein, fat, calcium, and magnesium. Cassava is a perennial crop with slow growth, necessitating the selection of intercrops with shorter harvest periods. Cowpea, a legume high in protein, is widely cultivated and suitable for intercropping with cassava. Intercropping these crops involves adjusting planting distances to optimize yield. This study aims to determine the optimal planting distance in an intercropping system that yields the highest productivity for the cassava variety “Mangu” and the cowpea varieties “Albina” and “Uno”. The research was conducted from January to June 2023 at the IPB Experimental Farm in Sawahbaru, Dramaga, Bogor, on Latosol soil, at an altitude of 207 meters above sea level. The study utilized a randomized complete block design with a single factor: the intercropping system pattern. The patterns tested were 1:2 (one row of cassava with two rows of cowpea) and 1:3 (one row of cassava with three rows of cowpea), consisting of: P1: “Mangu” and “Uno” 1:2; P2: “Mangu” and “Uno” 1:3; P3: “Mangu” and “Albina” 1:2; P4: “Mangu” and “Albina” 1:3; P5: “Mangu” monoculture; P6: “Uno” monoculture; P7: “Albina” monoculture. The results indicated that the P3 planting system yielded the highest crown height at 1, 5, and 6 months after planting (MAP), the highest canopy diameter at 4 months after planting, tuber production, and 100 seed weight of cowpea. The P4 system produced the highest stem diameter, number of leaves, number of pods, pod dry weight, and seed dry weight at 9 months after planting.

Deep neural networks have shown state-of-the-art results in audio source separation tasks in recent years. However, deploying such networks, especially on edge devices, is challenging due to memory and computation requirements. In this work, we focus on quantization, a leading approach for addressing these challenges. We start with a theoretical and empirical analysis of the signal-to-distortion ratio (SDR) in the presence of quantization noise, which presents a fundamental limitation in audio source separation tasks. These analyses show that quantization noise mainly affects performance when the model produces high SDRs. We empirically validate the theoretical insights and illustrate them on audio source separation models. In addition, the empirical analysis shows a high sensitivity to activations quantization, especially to the network's input and output signals. Following the analysis, we propose Fully Quantized Source Separation (FQSS), a quantization-aware training (QAT) method for audio source separation tasks. FQSS introduces a novel loss function based on knowledge distillation that considers quantization-sensitive samples during training and handles the quantization noise of the input and output signals. We validate the efficiency of our method in both time and frequency domains. Finally, we apply FQSS to several architectures (CNNs, LSTMs, and Transformers) and show negligible degradation compared to the full-precision baseline models.

This study introduces a reconfigurable and agile RF front-end (RFFE) architecture that significantly enhances the performance of software-defined radios (SDRs) by seamlessly adjusting to varying signal requirements, frequencies, and protocols. This flexibility greatly enhances spectrum utilization, signal integrity, and overall system efficiency—critical factors in aviation, where reliable communication, navigation, and surveillance systems are vital for safety. A versatile RF front-end is thus indispensable, enhancing connectivity and safety standards. We explore the integration of this flexible RF front-end in SDRs, focusing on the detailed design of essential components, such as receivers, transmitters, RF switches, combiners, and splitters, and their corresponding RF pathways. Comprehensive performance evaluations confirm the architecture’s reliability and functionality, including an extensive analysis of receiver gain, linearity, and two-tone test results. These assessments validate the architecture’s suitability for aviation radios and address considerations of size, weight, and power-cost (SWaP-C), demonstrating significant gains in operational efficiency and cost-effectiveness. The introduction of the new RF front-end on a single SDR board not only substantially reduces size and weight but also adds up to 18 dB gain to the received signal. It also allows for a high level of design flexibility, enabling seamless software transitions between different radios and the capacity to manage three times more radios with the same hardware, thereby significantly boosting the system’s ability to handle multiple radio channels efficiently.

This paper presents ReproRun, a flexible and extensible run-time framework for the reconfiguration of functions in field programmable gate array (FPGA) devices used in popular software-defined radio (SDR) platforms. The FPGA devices embed a hardwired or soft processing system (PS) which communicates with the programmable logic (PL) using a standard embedded bus interface. In order to apply a seamless run-time partial reconfiguration, we made use of all the related building blocks, design guidelines, and tools offered by AMD-Xilinx. In ReproRun, each partial bitstream targeting a reconfigurable region (RR) of the PL area comes with its respective firmware (i.e., software functions) that runs on the PS side. Our work guarantees run-time updates of the firmware without interrupting the functionality of other software processes running in the PS or PL, by employing a specialized controller, denoted as Run-timE firmWare reconfIguration contRollEr (REWIRE). The latter leverages the open asymmetric multiprocessing framework (OpenAMP). The partial bitstreams and respective firmware are fetched from a remote location using the trivial file transfer protocol (TFTP). ReproRun can be applied in different FPGA accelerators residing in disaggregated open radio access network (RAN) equipment, adaptive radio access technologies, and Edge servers hosting virtualized functions. [ABSTRACT FROM AUTHOR]

Spontaneous reporting systems remain pivotal for post-marketing surveillance and disproportionality analysis (DA) represents a recognized approach for early signal detection. Although DAs cannot be used per se as a standalone approach to assess a drug-related risk and cannot replace clinical judgment in the individual patient, their role remain irreplaceable for rapid detection of rare and unpredictable adverse drug reactions with strong drug-attributable component (e.g., designated medical events), especially when developed by a multidisciplinary team and combined with a careful case-by-case analysis (individual inspection of reports for causality assessment or to uncover reporting patterns and clinical features). In the recent past, a remarkable increase in publications of pharmacovigilance studies using DAs was observed, albeit the quality was debated: several publications contained "spin", namely, misinterpretation of results to infer causality, calculate incidence, or provide risk stratification, which may ultimately result in unjustified alarm. The development of dedicated Guidelines by the international READUS-PV project (https://readusstatement. org/) will allow reproducible and transparent publication of accurate DAs, thus supporting their real transferability and exploitation by regulators and clinicians. This review offered a perspective on methodological aspects (and understanding) of DAs, their rationale, design, reporting, and interpretation. [ABSTRACT FROM AUTHOR]

The Mendeleev Rise is located in the Amerasian Basin of the Arctic Ocean. The study synthesizes interpretations of regional seismic profiles of the 2D CDP seismic reflection method and rock survey data using special underwater vehicles on the slopes of seamounts and scarps. The rise is represented by alternating highs (horsts) and half-grabens. At the base of the horst sections, bright reflectors are distinguished, interpreted as volcanic rocks. The half-graben sections are wedge-shaped in section view and are similar in geometry to seaward-dipping reflectors (SDR) of continental passive volcanic margins. Rock sampling has shown that the horsts consist of the Paleozoic sedimentary rocks penetrated by intrusions. The Aptian–Albian sections with volcanics (basalts, trachybasalts, trachyandesites) were identified on the horsts. U/Pb dating of igneous rocks has showed that typical age of the rocks is 110–114 Ma. The Cretaceous igneous rocks contain zircons with ages ranging from the Pre-Barremian Mesozoic to Paleozoic and Precambrian. These zircons were captured by basaltic magma during its upward movement. The presence of these ancient zircons indicates that the Mendeleev Rise consists of the continental crust. A model of the crustal structure of the Mendeleev Rise is proposed. The base of the section visible on seismic profiles is characterized by predominance of volcanics (from basalts to trachyandesites on horsts and basically basalts in half-grabens). The upper and lower crust is approximately 20–30% replete with intrusions. At the base of the crust, a high-velocity layer up to 5 km thick is distinguished. It is assumed that its lower part is entirely represented by gabbro-type intrusions, and the upper part is the lowest part of the lower crust, maximally saturated with intrusions. [ABSTRACT FROM AUTHOR]

Three central steps during the biosynthesis of cytochalasan precursors, including reductive release, Knoevenagel cyclisation and Diels Alder cyclisation are not yet understood at a detailed molecular level. In this work we investigated the reductive release step catalysed by a hybrid polyketide synthase non‐ribosomal peptide synthetase (PKS‐NRPS) from the pyrichalasin H pathway. Synthetic thiolesters were used as substrate mimics for in vitro studies with the isolated reduction (R) and holo‐thiolation (T) domains of the PKS‐NRPS hybrid PyiS. These assays demonstrate that the PyiS R‐domain mainly catalyses an NADPH‐dependent reductive release of an aldehyde intermediate that quickly undergoes spontaneous Knoevenagel cyclisation. The R‐domain can only process substrates that are covalently bound to the phosphopantetheine thiol of the upstream T‐domain, but it shows little selectivity for the polyketide. [ABSTRACT FROM AUTHOR]

Since the software‐defined radio digital beamforming (DBF) system is the newest tendency in fifth‐generation (5G) development and based on its flexibility applied to antenna arrays, this research paper presents a smart antenna array architecture operating in C‐band (3.48 GHz). In developing DBF for 5G access points with beamforming capacities, it is first necessary to perform an accurate approach that identifies the position of the desired user and affects the beamforming processing. In this article, a feasible approach is represented to evaluate and test three angle‐of‐arrival algorithms. To ensure the robustness of the system, the system structure with its four main components, the transmit subsystem, the synchronization subsystem, the receive subsystem, and data processing are described in detail. This article presents a reasonably inexpensive prototype DBF in conjunction with a Universal Software Radio Peripheral B210 board. Experimental measurements and results confirm the suggested methodology. [ABSTRACT FROM AUTHOR]

Purpose: Assess the effects of selective dorsal rhizotomy (SDR) on motor function and quality of life in children with a Gross Motor Function Classification System (GMFCS) level of IV or V (non-ambulatory). Methods: This is a prospective, observational study in three tertiary neurosurgery units in England, UK, performing SDR on children aged 3–18 with spastic diplegic cerebral palsy, and a GMFCS level of IV or V, between 2012 and 2019. The primary outcome measure was the change in the 66-item Gross Motor Function Measure (GMFM-66) from baseline to 24 months after SDR, using a linear mixed effects model. Secondary outcomes included spasticity, bladder function, quality of life, and pain scores. Results: Between 2012 and 2019, 144 children who satisfied these inclusion criteria underwent SDR. The mean age was 8.2 years. Fifty-two percent were female. Mean GMFM-66 score was available in 77 patients (53.5%) and in 39 patients (27.1%) at 24 months after SDR. The mean increase between baseline and 24 months post-SDR was 2.4 units (95% CI 1.7–3.1, p < 0.001, annual change 1.2 units). Of the 67 patients with a GMFM-66 measurement available, a documented increase in gross motor function was seen in 77.6% (n = 52). Of 101 patients with spasticity data available, mean Ashworth scale decreased after surgery (2.74 to 0.30). Of patients' pain scores, 60.7% (n = 34) improved, and 96.4% (n = 56) of patients' pain scores remained the same or improved. Bladder function improved in 30.9% of patients. Conclusions: SDR improved gross motor function and reduced pain in most patients at 24 months after surgery, although the improvement is less pronounced than in children with GMFCS levels II and III. SDR should be considered in non-ambulant patients. [ABSTRACT FROM AUTHOR]

The shortwave downward solar irradiance (SDR) is an important factor that drives climate processes and energy production and can affect all living organisms. Observations of SDR at different locations around the world with different environmental characteristics have been used to investigate its long-term variability and trends at different time scales. Periods of positive trends are referred to as brightening periods and of negative trends as dimming periods. In this study we have used 30 years of pyranometer data in Thessaloniki, Greece, to investigate the variability of SDR under three types of sky conditions (clear-, cloudy- and all-sky). The clear-sky data were identified by applying a cloud screening algorithm. We have found a positive trend of 0.38 % / year for all-sky, ∼0.1%/year for clear-sky, and 0.41 % / year for cloudy conditions. The consistency of these trends, their seasonal variability, and the effect of the solar zenith angle have also been investigated. Under all three sky categories, the SDR trend is stronger in winter, with 0.7 , 0.4 , and 0.76 % / year , respectively, for all-, clear-, and cloudy-sky conditions. The next larger seasonal trends are in autumn— 0.42 and 0.19 % / year , for all and cloudy skies, respectively. The rest of the seasonal trends are significant smaller, close to zero, with a negative values in summer, for clear and cloudy skies. The SDR trend is increasing with increasing solar zenith angle, except under cloudy skies, where the trend is highly variable and close to zero. Finally, we discuss shorter-term variations in SDR anomalies by examining the patterns of the cumulative sums of monthly anomalies from the climatological mean, both before and after removing the long-term trend. [ABSTRACT FROM AUTHOR]

Soil erosion by water is one of the major environmental threats and it not only decreases agricultural productivity but also reduces water availability. This study aimed to estimate soil erosion and sediment yield and prioritize sub-watersheds for management options with RUSLE methodology in the Fakisi watershed, Northwestern Ethiopian highlands. Digital topography, rainfall, land cover, land management, and soil datasets were used to develop RUSLE model parameters. The study revealed that 339,031 tons of soil was lost annually and the mean soil loss was 35 t ha− 1 yr−1. Severe to extremely severe erosion was observed at 14.9 % of the watershed which accounted for 58 % of the total soil loss. The sediment delivery ratio (SDR) of the watershed was between 0.17–0.43 and the mean annual sediment yield was estimated at 27.2 t ha−1 yr−1. The sensitivity analysis revealed that soil erodibility and land management were the factors most contributing to the soil erosion processes. Sub-watersheds (SW9, SW6, SW10, SW7, and SW8) accounted for 72.4 % of the total erosion and covered 56 % of the overall watershed. These sub-watersheds were designated as significant erosion zones and recommended to implement integrated soil conservation interventions to deter the high soil loss and sediment yield.

Sawi Caisim (Brassica chinensis var. parachinensis) ialah tanaman sayuran yang memiliki nilai Drone sprayer merupakan inovasi yang digunakan untuk aplikasi pestisida. Penelitian tentang efektivitas dan efisiensinya untuk pengendalian gulma masih terbatas. Penelitian ini dilaksanakan di Desa Balung Lor Kecamatan Balung Kabupaten Jember pada bulan Agustus sampai Oktober 2022. Tujuan dari penelitian ini adalah membandingkan efektivitas dan efisiensi Drone sprayer dan knapsack sprayer menggunakan herbisida berbahan aktif 2,4-D dimetil amina;, konsentrasi 2 ml/liter, dosis 400 liter/ha. terhadap keanekaragaman gulma, kerapatan absolut, Summed Dominance Ratio (SDR), hasil panen, indeks ekologis dan waktu kerja alat semprot. Analisis data keefektifan menggunakan uji Mann-Whitney. Efisiensi alat semprot menggunakan persamaan waktu kerja menurut Andremico. Hasil penelitian: keanekaragaman gulma perlakuan drone Sprayer terdiri atas 2 ordo, 2 famili, 5 spesies, didominasi oleh Leptochloa chinensis gulma golongan rerumputan, knapsack Sprayer 4 ordo, 4 famili, 6 spesies, didominasi oleh Ipomoea aquatica gulma berdaun lebar. Kerapatan Mutlak drone sprayer (2,20±1,30) individu per m2, lebih rendah dibanding Knapsack sprayer (18,6±8,55) individu per m2. Hasil panen drone sprayer (58,72±17,14) gram per rumpun berbeda tidak nyata dibanding knapsack sprayer (58,22±13,50) gram per rumpun. Indeks Shannon-Wiener (H’) Drone sprayer 1,47, Knapsack Sprayer 1,15. Indeks kesamakan Sorensen (ISS) 25%. Waktu kerja drone sprayer 0.17 jam/ha; lebih efisien dibanding knapsack sprayer yaitu 11.57 jam/ha.

BackgroundAlthough the impact of hypertension on carotid intima-media thickness (IMT) and plaques has been well established, its association with femoral IMT and plaques has not been extensively examined. In addition, the role of the ratio of systolic and diastolic pressure (SDR) in the subclinical atherosclerosis (AS) risk remains unknown. We assessed the relationship between SDR and carotid and femoral AS in a general population.MethodsA total of 7,263 participants aged 35–74 years enrolled from January 2019 to June 2021 in a southeast region of China were included in a cross-sectional study. Systolic and diastolic blood pressure (SBP and DBP) were used to define SDR. Ultrasonography was applied to assess the AS, including thickened IMT (TIMT) and plaque in the carotid and femoral arteries. Logistic regression and restricted cubic spline (RCS) models were the main approaches.ResultsThe prevalence of TIMT, plaque, and AS were 17.3%, 12.4%, and 22.7% in the carotid artery; 15.2%, 10.7%, and 19.5% in the femoral artery; and 23.8%, 17.9% and 30.0% in either the carotid or femoral artery, respectively. Multivariable logistic regression analysis found a significant positive association between high-tertile SDR and the higher risk of overall TIMT (OR = 1.28, 95% CI = 1.10–1.49), plaques (OR = 1.36, 95%CI = 1.16–1.61), or AS (OR = 1.36, 95% CI = 1.17–1.57), especially in the carotid artery. RCS analysis further revealed the observed positive associations were linear. Further analyses showed that as compared to the low-tertile SDR and non-hypertension group, high-tertile SDR was associated with increased risks of overall and carotid TIMT, plaques, or AS in both groups with or without hypertension.ConclusionsSDR is related to a higher risk of subclinical AS, regardless of hypertension or not, suggesting that as a readily obtainable index, SDR can contribute to providing additional predictive value for AS.

This paper explores the potential of an Integrated Sensing and Communication (ISAC) system to enhance search-and-rescue operations. While prior research has explored ISAC capabilities in Unmanned Aerial Vehicles (UAVs), our study focuses on addressing the specific challenges posed by modern communication standards (e.g., power, frequency, and bandwidth limitations) in the context of search-and-rescue missions. The paper details effective methods for processing echoed signals generated by downlink transmissions and evaluates key performance indicators, including Noise Equivalent Sigma Zero (NESZ) and channel capacity. Additionally, we utilize synchronization uplink signals transmitted by User Equipment (UE) to improve target detection and classification of possible victims by fusing SAR imagery with triangulation results from uplink signals. An experimental campaign validates the proposed setup by integrating SAR images of the environment with active localization results, both produced by a UAV equipped with a Software Defined Radio (SDR) payload. Our results demonstrate the system’s capability to detect and localize buried targets in avalanche scenarios, with localization errors ranging from centimeters to 10 m depending on environmental conditions. This successful integration highlights the practical applicability of our approach in challenging search-and-rescue missions.

This work presents the development and testing of an experimental web-based SDR (software-defined radio) monitoring system for indirect solar activity detection, which has the ability to estimate and potentially predict various events in space and on earth, including solar flares, coronal mass ejections, and geomagnetic storms. The proposed system can be used to investigate the effect of solar activity on the propagation of very-low-frequency (VLF) signals. The advantages and benefits of the given approach are as follows: increasing measurement accuracy and eventual solar activity identification by combining measurements from multiple spatially distributed SDRs. The verification process involves carrying out several experiments comparing data from the GOES satellite system and the Dunksin SuperSID system with information received by the SDR monitoring system. Then, utilizing Pearson correlation coefficients, the measured data from the SDRs, along with those from the GOES satellite system and the Dunsing monitoring station, are investigated. At the time of a solar flare, the correlation value is above 90% for most of the stations used. Combining the signal-to-noise ratio via summation also shows an improvement in the results, with a correlation above 98%.