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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]

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]

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]

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]

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]

An increase in warming in the Arctic relative to the rest of the Northern Hemisphere or the globe continues attracting attention, despite the large amount of research being conducted. Possible causes of the Arctic amplification have been considered and continue to be discussed in many articles and reviews. In this article, for the first time, a quantitative assessment of the role of atmospheric transports in the formation of variability and trends in the mean near-surface air temperature (SAT) in the Arctic and at adjacent latitudes of the Northern Hemisphere is carried out and an analytical description of amplification in high latitudes is proposed. For the study, data from NCEP and ERA5 reanalyses for 1989–2020 and a representation of the set of events of air exchange between latitudes in a simple hemispheric atmospheric model under constant conditions at the boundaries, on the basis of which analytical expressions are obtained for the standard deviation ratios (SDRs) and temperature trends in neighboring areas. The degree of closeness between the empirical and model ratios of SDR and trends is taken as a contribution measure of air exchange to the increase in SDR and trends during warming. It has been found that the exchange between the polar and adjacent regions reaches lower latitudes as the polar region expands from 70° N up to 60° N. The latitude to which the polar air propagates on average decreases with the trend taken into account in the SDR, which confirms the effect of warming on the increase in air mass exchange. The model value of the increase in the average air temperature trend in the polar region of an isolated homogeneous atmosphere above the hemisphere relative to the trend in the adjacent region is determined by the ratio of their areas multiplied by the ratio of the trend determination coefficients. An increase in the temperature trend in the polar region of the real atmosphere, according to the NCEP and ERA5 reanalyses for 1989–2020, was compared with the model value, thereby assessing the contribution of air mass exchange to the increase in the temperature trend in the polar region. It was found that the exchange explains 54% of the increase in the air temperature trend (Arctic amplification) in the region of 90–60° N on average per year and 66% in the cold year part relative to the rest of the Northern Hemisphere. If we take into account the established southern boundary of air mass exchange between the polar and adjacent regions, then the amplification of an air temperature trend in the area of 90–60° N relative to the trend in the adjacent area, with which the exchange of air masses occurs, will almost completely (by 93% on average per year) be the result of exchange and, in the area of 90°–70° N, it will mostly be the result of exchange (by 74% on average per year). [ABSTRACT FROM AUTHOR]

The aim of this paper is to create an autonomous reconfigurable radio communication system that can produce an adequate transmission rate according to propagation medium fluctuation while maintaining a higher quality of service (QoS). In this work, we have achieved an experimental implementation of adaptive modulation technique using SDR platforms as USRP B210, RTL-SDR and HackRF One. The implemented system provides a real time data communication equipped by an adaptive modulation techniques. The system autonomously chooses the most suitable modulation among BPSK, QPSK and 8-PSK based on the estimation of link quality measured by the signal to noise ratio (SNR). [ABSTRACT FROM AUTHOR]

A promising technique for increasing the number of users in a wireless network is Non-Orthogonal Multiple Access (NOMA) which improves the spectral efficiency and unfairness in communication by using same wireless resource to more than one user. The wireless technologies such as millimeter wave communication, physical layer security, grant free communication, massive Multiple Input Multiple Output communication, and visible light communication are combined with NOMA flexibly to increase energy efficiency, scalability, and spectral efficiency to enhance the performance of future wireless communication network. In this paper, we provide a comprehensive review and detailed description on combination of NOMA with existing 5G and beyond 5G wireless techniques. The benefits of these techniques when combined with NOMA are described to identify the supremacy of the NOMA with 5G wireless systems. Moreover, we also describe the existing challenges faced during combination of NOMA with 5G and beyond 5G and future research directions are also identified. [ABSTRACT FROM AUTHOR]

The proposed work attempts to improve the near-end intelligibility of speech at very low signal-to-noise ratios (SNRs). Additionally, the prerequisite of noise statistics that existing intelligibility improvement methods require is not a limitation of the proposed approach. To this end, the shaping parameters of the voice transformation function (VTF) are optimized. This optimization of the shaping parameters of the VTF corresponds to the combined modification that includes formant shifting, nonuniform time scaling, smoothing, and energy re-distributions in comprehensive learning particle swarm optimization (CLPSO) framework. The optimal parameters of the combined modifications are obtained by jointly maximizing the short time objective intelligibility, perceptual evaluation of speech quality and signal-to-distortion ratio metrics being used as the cost function in CLPSO. The outcome at the end is an improvement in intelligibility that is significantly higher than the ones obtained by applying these methods individually, while preserving the quality. As a side result, a Gaussian process regression is also employed to estimate the shaping parameters of VTF at arbitrary SNRs—other than the ones which were used during CLPSO training. [ABSTRACT FROM AUTHOR]

The present study proposes a novel method for speech intelligibility improvement by optimally shifting the formants using a trapezoidal voice transformation function. The shaping parameters of this function are determined by maximizing various performance measures using a comprehensive learning particle swarm optimization (CLPSO) algorithm. These measures include the short time objective intelligibility (STOI), perceptual evaluation of speech quality (PESQ) and signal to distortion ration (SDR). The proposed method does not requires a priori knowledge about the noise statistics in designing the voice transformation function. Although, the shaping parameters are obtained at specific SNRs, a Gaussian process (GP) regression model is trained to compute these parameters for arbitrary SNRs. The performance of the proposed method is demonstrated on various databases which include Hearing In Noise Test (HINT) a French database, NOIZEUS (ENGLISH) and CHAINS (ENGLISH) databases at different levels of engine noises arising from a running car at various speeds. The results of the investigation convincingly demonstrate that the proposed approach could improve the speech intelligibility, while preserving the quality. [ABSTRACT FROM AUTHOR]

: Selective dorsal rhizotomy (SDR) and intrathecal baclofen (ITB) pump placement are two surgical options in children affected by spasticity secondary to cerebral palsy 1. The latest literature is an enlarging indication for SDR in case of ITB failure in non-ambulant patients as an alternative to pump reimplantation to reduce spasticity and facilitate patients’ care.A retrospective single-center study has screened all children diagnosed with spastic tetraparesis who underwent in the last 10 years SDR and had previously ITB pump implanted. A cohort of six patients was pooled out. Furthermore, pertinent literature has been reviewed.Indication for pump removal was pump pocket infection, parents’ decision, and poor response to ITB. Patients’ amount of lifetime with the pump implanted has been 6.9 years. The preoperative and postoperative Ashworth scores were statistically different in both procedures (p= 0.005 and p= 0.,02). Only two studies investigated the pediatric population undergoing SDR in the occurrence of ITB pump removal. Authors are offering SDR to all children, regardless of GMFCS groups and previous ITB pump placement. In conclusion, SDR represents a valid tool in neurosurgeon’s hands to help ameliorate patients’ long-lasting quality of life, reducing the severity of the spasticity and leading to better management by caregivers.: Selective dorsal rhizotomy (SDR) and intrathecal baclofen (ITB) pump placement are two surgical options in children affected by spasticity secondary to cerebral palsy 1. The latest literature is an enlarging indication for SDR in case of ITB failure in non-ambulant patients as an alternative to pump reimplantation to reduce spasticity and facilitate patients’ care.A retrospective single-center study has screened all children diagnosed with spastic tetraparesis who underwent in the last 10 years SDR and had previously ITB pump implanted. A cohort of six patients was pooled out. Furthermore, pertinent literature has been reviewed.Indication for pump removal was pump pocket infection, parents’ decision, and poor response to ITB. Patients’ amount of lifetime with the pump implanted has been 6.9 years. The preoperative and postoperative Ashworth scores were statistically different in both procedures (p= 0.005 and p= 0.,02). Only two studies investigated the pediatric population undergoing SDR in the occurrence of ITB pump removal. Authors are offering SDR to all children, regardless of GMFCS groups and previous ITB pump placement. In conclusion, SDR represents a valid tool in neurosurgeon’s hands to help ameliorate patients’ long-lasting quality of life, reducing the severity of the spasticity and leading to better management by caregivers.: Selective dorsal rhizotomy (SDR) and intrathecal baclofen (ITB) pump placement are two surgical options in children affected by spasticity secondary to cerebral palsy 1. The latest literature is an enlarging indication for SDR in case of ITB failure in non-ambulant patients as an alternative to pump reimplantation to reduce spasticity and facilitate patients’ care.A retrospective single-center study has screened all children diagnosed with spastic tetraparesis who underwent in the last 10 years SDR and had previously ITB pump implanted. A cohort of six patients was pooled out. Furthermore, pertinent literature has been reviewed.Indication for pump removal was pump pocket infection, parents’ decision, and poor response to ITB. Patients’ amount of lifetime with the pump implanted has been 6.9 years. The preoperative and postoperative Ashworth scores were statistically different in both procedures (p= 0.005 and p= 0.,02). Only two studies investigated the pediatric population undergoing SDR in the occurrence of ITB pump removal. Authors are offering SDR to all children, regardless of GMFCS groups and previous ITB pump placement. In conclusion, SDR represents a valid tool in neurosurgeon’s hands to help ameliorate patients’ long-lasting quality of life, reducing the severity of the spasticity and leading to better management by caregivers.: Selective dorsal rhizotomy (SDR) and intrathecal baclofen (ITB) pump placement are two surgical options in children affected by spasticity secondary to cerebral palsy 1. The latest literature is an enlarging indication for SDR in case of ITB failure in non-ambulant patients as an alternative to pump reimplantation to reduce spasticity and facilitate patients’ care.A retrospective single-center study has screened all children diagnosed with spastic tetraparesis who underwent in the last 10 years SDR and had previously ITB pump implanted. A cohort of six patients was pooled out. Furthermore, pertinent literature has been reviewed.Indication for pump removal was pump pocket infection, parents’ decision, and poor response to ITB. Patients’ amount of lifetime with the pump implanted has been 6.9 years. The preoperative and postoperative Ashworth scores were statistically different in both procedures (p= 0.005 and p= 0.,02). Only two studies investigated the pediatric population undergoing SDR in the occurrence of ITB pump removal. Authors are offering SDR to all children, regardless of GMFCS groups and previous ITB pump placement. In conclusion, SDR represents a valid tool in neurosurgeon’s hands to help ameliorate patients’ long-lasting quality of life, reducing the severity of the spasticity and leading to better management by caregivers. [ABSTRACT FROM AUTHOR]

This paper presents a non-wide-sense stationary uncorrelated scattering (non-WSSUS) vehicular channel emulator based on software-defined radios (SDR). The proposed channel emulator can be used for testing new radio communication systems, and it is able to introduce wideband channel distortions over passband signals. Likewise, an affordable and accurate SDR-based channel emulator implementation is reached, as can be seen when it is compared with state-of-the-art channel emulator implementations whose architectures are expensive and do not implement local non-stationary channel models. Current proposals implement non-stationary models by concatenating local stationary processes. The performance of the channel emulator is verified via channel impulse response comparisons and via bit error rate computation when the channel emulator is used for testing vehicular communication systems. Emulation results show that the proposed channel emulator can reproduce non-WSSUS channel propagation environments with exactness, enabling it to be used for testing future vehicular communication systems. [ABSTRACT FROM AUTHOR]

Background: Although members of the SDR gene family (short chain dehydrogenase) are distributed in kingdom of life, they have diverse roles in stress tolerance mechanism or secondary metabolite biosynthesis. Nevertheless, their precise roles in gene expression or regulation under stress are yet to be understood. Methods: As a case study, we isolated, sequenced and functionally characterized the 3β-HSD promoter from Digitalis ferruginea subsp. ferruginea in Arabidopsis thaliana. Results: The promoter fragment contained light and stress response elements such as Box-4, G-Box, TCT-motif, LAMP element, ABRE, ARE, WUN-motif, MYB, MYC, W box, STRE and Box S. The functional analysis of the 3β-HSD promoter in transgenic Arabidopsis seedlings showed that the promoter was expressed in cotyledon and root elongation zone in 2 days' seedlings. However, this expression was extended to hypocotyl and complete root in 6 days' seedlings. In 20 days-old seedlings, promoter expression was distributed to the whole seedling including hydathodes aperture, vascular bundle, shoot apical meristem, trichomes, midrib, leaf primordia, hypocotyl and xylem tissues. Further, expression of the promoter was enhanced or remained stable under the different abiotic stress conditions like osmotic, heat, cold, cadmium or low pH. In addition, the promoter also showed response to methyl jasmonate (MeJA) application. The expression could not be induced in wounded cotyledon most likely due to lack of interacting elements in the promoter fragment. Conclusions: Taken together, the 3β-HSD promoter could be a candidate for the development of transgenic plants especially under changing environmental conditions. [ABSTRACT FROM AUTHOR]

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This paper focuses primarily on the study of the implementation of Non-orthogonal multiple access (NOMA) systems on Software defined radio (SDR) platforms, since NOMA has been recognized as a key enabling technology for the fifth generation (5G) wireless networks. A comprehensive review of the original birth, the latest trends, and the future research directions of NOMA is given in this paper. Specifically, several Successive Interference Cancellation (SIC) receivers are provided with mathematical analysis, such as the Ideal SIC receiver, Symbol-level SIC receiver, Codeword-level SIC receiver and Log likelihood ratio (LLR) based receivers. Furthermore, the bit error rate of two users' signals is analyzed by implementing the NOMA system with and without the SIC using GNU Radio software. In addition, the performance of orthogonal multiple access (OMA) and NOMA systems is compared in terms of rate pairs (throughput), spectral efficiency and energy efficiency. Finally, the results reveal that the NOMA system performs better than OMA systems and it will be highlighted that SDR is a flexible platform to implement and test future wireless technologies. [ABSTRACT FROM AUTHOR]

The performance of rolling bearings is often reduced due to the additional wear introduced by sliding contact. Therefore, it is very vital to study the evolution of the sliding wear process of the bearing material friction pairs. The tribological performance of the two kinds of material pairs, including GCr15–GCr15/Si3N4–GCr15, was analysed under oil-lubricated conditions with a pin-on-disc rig. The results show that with high initial surface roughness, the friction coefficients of the two pairs decrease as the load and speed increase, while in the stable wear stage, Si3N4–GCr15 friction pairs show better tribological properties than those of GCr15–GCr15 friction pairs. For lacks of information-rich studies and techniques of worn surfaces topography, an in-suit 3D microscope is adopted to obtain the topographies of friction and wear surface during the wear tests. The results prove that 3D topography can clearly characterize the wear process. 3D topography shows identical trend with the surface roughness (Ra, Sa and Sq) and the friction coefficients. Citing mixing parameter Sdr explores its feasibility for characterizing worn surfaces. The results illustrate that there is a close relationship between Sdr and 3D topography, which can reflect the friction transition of a surface from running into severe wear. A low surface roughness indicates a small Sdr. [ABSTRACT FROM AUTHOR]

One of the main challenges in controlling soil erosion and sediment load in desert areas is the lack of data. Therefore, estimation of soil erosion in such watersheds is possible by determining the sediment delivery ratio (SDR). The purpose of this study is comparison of the results of different methods for calculating SDR with its actual amount in arid areas and determining the best method. The study areas include 6 watersheds for calibration phase and 1 watershed for validation phase in Semnan province in the north of Iran. The volume of trapped sediment upstream the study area check-dams was calculated by evaluating the changes in the dams’ reservoirs morphological characteristics between successive events. The rain simulator method was used to obtain actual SDR. The SDR value was also calculated using 14 empirical methods. Comparison of observed and calculated SDR values indicates the different performance of the empirical methods. It is not possible to introduce one of these methods for calculating SDR in all studied basins, but due to the lowest relative error rate of the USDA-SCS (1983) model, this model was calibrated. The relative mean squared error for calibrated model was 0.2241 (low error). The results obtained by the calibrated model corresponded to about 80% to the values of the observed SDR. Finally, the relative error rate in the validation stage for the basin that was used in validation of the calibrated model was calculated as 1.17%, so the results of the calibrated model can be accepted. [ABSTRACT FROM AUTHOR]

The future of dependable wireless communication will encompass a much eclectic range of applications. Not only are traditional telecommunication facilities such as text messaging, audio and video calling, video download and upload, web browsing, and social networking being improved but also a wide range of sensors and devices in the "Internet of things," such as "smart cities" and smart hospital applications are being adopted. Researchers are trying hard to ensure timely detection of various diseases anytime and anywhere. In this research, a portable and multifunctional software-defined radio (SDR) platform is designed to detect different activities of human life, in particular for the monitoring of health. The wireless channel state information (WCSI) in the presence of the human body is investigated to capture movements using different frequency bands and is the key idea of this work. Orthogonal frequency division multiplexing (OFDM) with 64 subcarriers and the magnitude and phase responses in the frequency domain are used to capture the WCSI of the activity. The design is validated through simulation and real-time experiments. However, it is widely accepted that simulation results fail to capture real-life situations. Extensive and repeated real-time experiments are carried out on the hardware platform to ensure that the activity is detected accurately. The results achieved by detecting hand motion activity ensure that the system is capable of detecting human body motions and vital signs. [ABSTRACT FROM AUTHOR]

Purpose: Investigate the effect of age category (1–9 years vs 10–18 years), sex, Gross Motor Function Classification System (GMFCS) level, and presence of dystonia on changes in eight function test parameters 24 months after selective dorsal rhizotomy (SDR). Methods: Prospective, single-center study of all children aged 3–18 years with bilateral cerebral palsy with spasticity who underwent SDR at a tertiary pediatric neurosurgery center between 2012 and 2019. A linear mixed effects model was used to assess longitudinal changes. Results: From 2012 to 2019, 42 children had follow-up available at 24 months. Mean GMFM-66 scores increased after SDR (mean difference 5.1 units: 95% CI 3.05–7.13, p < 0.001). Statistically significant improvements were observed in CPQoL, PEDI Self-care and Mobility, 6MWT, Gillette, and MAS scores. There was no significant difference in the improvements seen for age category, sex, GMFCS level, and presence of dystonia for most of the parameters tested (5/8, 6/8, 5/8, and 6/8 respectively). Conclusion: SDR may improve gross and fine motor function, mobility and self-care, quality of life, and overall outcome based on extensive scoring parameter testing at 24 months. Atypical patient populations may benefit from SDR if appropriately selected. Multi-center, prospective registries investigating the effect of SDR are required. [ABSTRACT FROM AUTHOR]

For last few years, the usage of bandwidth is being increased rapidly due to the growth of advanced applications and services. Therefore, it is required to depend on various multiple access techniques to maximize the spectrum efficiency. Non-orthogonal multiple access (NOMA) is recognized as a prominent technique to increase the spectrum utilization for upcoming wireless technologies. In this paper, the experimental validation of NOMA system is carried out with the help of software defined radio testbed by considering 4 users maintaining various distances from the base station. The necessity of successive interference cancellation (SIC) for NOMA is tested experimentally and results are presented. Obtained results show that the NOMA system has a better improvement in terms of bit error rate after applying SIC. [ABSTRACT FROM AUTHOR]

Lately, a rising number of incidents between unmanned aerial vehicles (UAVs) and airplanes have been reported in airports and airfields. In order to help cope with the problem of unauthorized UAV operations, in this paper we evaluate the use of low cost SDR platforms (software defined radio) for the implementation of a jammer able to generate an effective interfering signal aimed at the GPS navigation system. Using a programmable BladeRF x40 platform from Nuand and the GNU radio software development toolkit, several interference techniques were studied and evaluated, considering the spectral efficiency, energy efficiency and complexity. It was shown that the tested approaches are capable of stopping the reliable reception of the radionavigation signal in real-life scenarios, neutralizing the capacity for autonomous operation of the vehicle. [ABSTRACT FROM AUTHOR]

The pseudo-analog wireless video transmission technology can improve the effectiveness, reliability, and robustness of the conventional digital system in video broadcast scenarios. Although some prototypes of IEEE 802.11 series have been developed for researchers to do simulations and experiments, they are usually expensive and provide very limited access to the physical layer. More importantly, these prototypes cannot be used to verify the correctness of the new proposed pseudo-analog wireless video transmission algorithms directly due to limited modulation modes they can support. In this paper, we present a novel design of software radio platform (SDR)-based pseudo-analog wireless video transceiver which is completely transparent and allows users to learn all the implementation details. Firstly, we prove that the analog method can also achieve the optimal performance as the digital method from the perspective of the rate-distortion theory. Then, we describe the two hardware implementation difficulties existed in the designing process including the data format modification and the non-linear distortion. Next, we introduce the implementation details of the designed transceiver. Finally, we analyze the performance of the designed transceiver. Specifically, the results show that the designed system can work effectively in both simulations and experiments. [ABSTRACT FROM AUTHOR]

Introduction: Spinal reflexes reorganize in cerebral palsy (CP), producing hyperreflexia and spasticity. CP is more common among male infants, and gender might also influence brain and spinal–cord reorganization. This retrospective study investigated the frequency of higher-graded EMG responses elicited by electrical nerve–root stimulation during selective dorsal rhizotomy (SDR), prior to partial nerve– root deafferentation, considering not only segmental level and body side, but also gender. Methods: Intraoperative neuromonitoring (IOM) was used in SDR to pinpoint the rootlets most responsible for exacerbated stimulation-evoked EMG patterns recorded from lower-limb muscle groups. Responses were graded according to an objective response-classification system, ranging from no abnormalities (grade 0) to highly abnormal (grade 4+), based on ipsilateral spread and contralateral involvement. Non-parametric analysis of data with repeated measures was primarily used in investigating the frequency distribution of these various EMG response grades. Over 7000 rootlets were stimulated, and the results for 65 girls and 81 boys were evaluated, taking changes in the composition of patient groups into account when considering GMFCS levels. Results: The distribution of graded EMG responses varied according to gender, laterality, and level. Higher-graded EMG responses were markedly more frequent in the boys and at lower segmental levels (L5, S1). Left-biased asymmetry in higher–graded rootlets was also more noticeable in the boys and in patients with GMFCS level I. A close link was observed between higher-grade assessments and left-biased asymmetry. Conclusions: Detailed insight into the patient's initial spinal-neurofunctional state prior to deafferentation suggests that differences in asymmetrical spinal reorganization might be attributable to a hemispheric imbalance. [ABSTRACT FROM AUTHOR]

Introduction: Selective dorsal rhizotomy (SDR) consists of microsurgical partial deafferentation of sensory nerve roots (L1–S2). It is primarily used today in decreasing spasticity in young cerebral palsy (CP) patients. Intraoperative monitoring (IOM) is an essential part of the surgical decision-making process, aimed at improving functional results. The role played by SDR-IOM is examined, while realizing that connections between complex EMG responses to nerve–root stimulation and a patient's individual motor ability remain to be clarified. Methods: We conducted this retrospective study, analyzing EMG responses in 146 patients evoked by dorsal–root and rootlet stimulation, applying an objective response–classification system, and investigating the prevalence and distribution of the assessed grades. Part1 describes the clinical setting and SDR procedure, reintroduced in Germany by the senior author in 2007. Results: Stimulation-evoked EMG response patterns revealed significant differences along the segmental levels. More specifically, a comparison of grade 3+4 prevalence showed that higher-graded rootlets were more noticeable at lower nerve root levels (L5, S1), resulting in a typical rostro-caudal anatomical distribution. Conclusions: In view of its prophylactic potential, SDR should be carried out at an early stage in all CP patients suffering from severe spasticity. It is particularly effective when used as an integral part of a coordinated, comprehensive spasticity program in which a team of experts pool their information. The IOM findings pertaining to the anatomical grouping of grades could be of potential importance in adjusting the SDR-IOM intervention to suit the specific individual constellation, pending further validation. Trial registration: ClinicalTrials.gov ID: NCT03079362 [ABSTRACT FROM AUTHOR]

Erosion and solid transport is a tricky and complex problem that negatively affects natural and urban environments. In Algeria, the effects of this phenomenon are apparent; their impact is no less devastating in the long term than the other spectacular catastrophic phenomena that can be observed. Sixty-five large dams in Algeria are threatened by the reduction of 62% of their storage capacity because of the siltation problem (ANBT) (National Agency for Dams and Water Transfers). The main objective of this work is the evaluation of the impact of the erosion phenomenon on Bechar watershed which is in an area characterized by an arid climate. The universal soil loss equation was used. This model is based on the combination of the five factors (erosivity, erodibility, topography, vegetation cover and support practices) that directly influence this phenomenon. Analytical hierarchy process is used to give a weighting value of each factor according to its degree of influence on the phenomenon. The sediment delivery ratio is calculated to determine the amount of soil that will arrive at the outlet of the watershed and contribute to the storage structures siltation. The obtained results will undoubtedly help decision makers to understand the threat of erosion degree in the study area in order to better take the necessary measures to face this issue. [ABSTRACT FROM AUTHOR]

Recent advances associated with wireless technology are presenting fast development for new wireless telecommunications generations. Development that creates a need for operators and individuals to use hybrid equipment combining the different generation protocol stacks to handle availability and quality of services. Software Defined Radio SDR technology offers new paradigm, allowing single device to handle several digital telecommunications schemes simultaneously. In this article, we are using low cost RTL-SDR front-end receiver to simplify traditional complex hardware and proprietary equipment systems for carrier detection. Our developed solution use the RTL-SDR dongle to detect and monitor nearby carriers activities. [ABSTRACT FROM AUTHOR]

Software defined radio (SDR) is a vast and emerging field that requires the design of various technologies such as antenna, RF, IF, and digital baseband subsystems. Among all these technologies, data converters that convert signals between analog and digital domains are highly crucial. On the other hand field programmable gate arrays (FPGAs) based platforms are being preferred for evaluating and implementing the digital communication concepts due to their programmability and reconfigurability. As a result they are well suited for the design of SDR technology. In this research work, we develop a platform where high-speed data converters are interfaced with high performance FPGAs. Interfaces are designed for analog-to-digital convertors (ADC) and digital-to-analog convertors (DAC) to communicate with FPGAs. For the interface design between ADC and FPGA, a double data rate and a low voltage differential signalling based serial output is adopted. And, for the interface design between DAC and other FPGA, parallel complementary metal oxide semiconductor outputs are used. To reconfigure the modes and parameters of the data convertors, serial peripheral interface data controllers have been designed. We have through simulations evaluated the performance of our designed interfaces between data convertors and FPGAs. [ABSTRACT FROM AUTHOR]

The Mauritius Deuterium Telescope (MDT) is an upcoming low-frequency array being built in Mauritius to observe the Deuterium hyperfine line at 327.4 MHz. This project is an opportunity to develop new techniques in radio astronomy considering the advent of the Square Kilometre Array in a few years time. The design of the MDT array targets a low-cost hybrid system consisting of Software Defined Radios (SDR) as the analogue receiver and digitiser, while a gaming Graphics Processing Unit (GPU) is used to implement the digital processing pipeline. We present the design and layout of the instrument. A polyphase filterbank (PFB) is implemented in parallel on the GPU. For an 11-station array, the PFB kernel has a computational throughput of 39.8 GiB/s. Since processing and copying can be overlapped, the latency of the processing kernels can be hidden behind the data copying to GPU memory; effectively establishing an input rate limit around 12 GiB/s due to the PCIe x16. Still, this will allow the hybrid SDR-GPU pipeline to perform real-time data acquisition and processing for the MDT. Finally, we present results from tests with real data from an FM antenna at 327 MHz. [ABSTRACT FROM AUTHOR]

Special Drawing Rights are reserve assets which ought to provide liquidity in times of a country's financial distress. It is a potential claim on freely usable currencies of International Monetary Fund member countries. This article examines the possible effects of a global Special Drawing Rights implementation by the International Monetary Fund in case of a collapse of one of the major currencies. The question addressed is if a distressed fiat currency can be bailed out effectively by triggering the designation mechanism to the International Monetary Fund member countries The results indicate that the liquidity benefit per created Special Drawing Rights unit would proportionally increase with the rate of money supply. [ABSTRACT FROM AUTHOR]

With rapid increase in new applications and services, there is huge demand for internet bandwidth. Several researchers around the world have found that, majority of licensed bands (mostly terrestrial TV band) are either unused or underused. These underutilized bands allocated for TV transmission are known as TV white space (TVWS). For effective utilization of TVWS, the IEEE 802.22 is proposed. The IEEE 802.22 wireless regional area network (WRAN) is the latest standard for effective utilization of TV bands. This standard is based on orthogonal frequency division multiplexing with various modulation techniques to provide different data rates. In this paper, an implementation framework for physical layer of IEEE 802.22 WRAN standard for normal mode is demonstrated and analyzed. This transceiver is implemented using the National Instruments Laboratory Virtual Instrument Engineering Workbench programming software on the National Instruments universal software radio peripheral 2952R. We have also analyzed different blocks of IEEE 802.22 based on their execution time, and identify the critical blocks of IEEE 802.22 that should be optimized for real-time applications for commercial product development and field deployments. We have also highlighted the difference between theoretical and practical performance of the considered error control codes for IEEE 802.22 specified block size. Additionally, various covariance based spectrum sensing methods are also analyzed for real-world environment. [ABSTRACT FROM AUTHOR]

Air traffic control is moving from independent primary surveillance radar to the automatic dependent surveillance-broadcast (ADS-B) system. This holds the potential of reducing the total cost of deployment and improving the detection accuracy of aircraft. However, as currently being deployed these systems lack strong security mechanisms and are susceptible to a variety of radio frequency attacks. These attacks have been proffered by attackers at hacker conventions and by academic researchers. And many online sites even provide hacking “how-to” instructions on ADS-B. Is it possible for an attacker to manipulate ADS-B to interfere with an aircraft in flight using readily available tools? Using a basic $200 software defined radio (SDR) transceiver we simulated an ADS-B replay attack. Despite the advancement in SDR we find that the quality of SDR transceivers are still insufficient to perform a replay attack. [ABSTRACT FROM AUTHOR]

Software-Defined Network (SDN) is a promising architecture for next generation Internet. SDN can achieve Network Function Virtualization much more efficiently than conventional architectures by splitting the data and control planes. Though SDN emerged first in wired network, its wireless counterpart Software-Defined Wireless Network (SDWN) also attracted an increasing amount of interest in the recent years. Wireless networks have some distinct characteristics compared to the wired networks due to the wireless channel dynamics. Therefore, network controllers present some extra degrees of freedom, such as taking measurements against interference and noise, or adapting channels according to the radio spectrum occupation. These specific characteristics bring about more challenges to wireless SDNs. Currently, SDWN implementations are mainly using customized firmware, such as OpenWRT, running on an embedded application processor in commercial WiFi chips, and restricted to layers above lower Media Access Control. This limitation comes from the fact that radio hardware usually require specific drivers, which have a proprietary implementation by various chipset vendors. Hence, it is difficult, if not impossible, to achieve virtualization on the radio hardware. However, this status has been changing as Software-Defined Radio (SDR) systems open up the entire radio communication stack to radio hobbyists and researchers. The bridge between SDR and SDN will make it possible to bring the softwarization and virtualization of wireless networks down to the physical layer, which will unlock the full potential of SDWN. This paper investigates the necessity and feasibility of extending the virtualization of wireless networks towards the radio hardware. A SDR architecture is presented for radio hardware virtualization in order to facilitate SDWN design and experimentation. We do believe that by adopting the virtualization-oriented hardware accelerator design presented here, an all-layer end-to-end high performance SDWN can be achieved. [ABSTRACT FROM AUTHOR]

Background: Severe spasticity adversely affects patient functional status and caregiving. No previous study has compared efficacy between dorsal root entry zone lesioning (DREZL) and selective dorsal rhizotomy (SDR) for reduction of spasticity. This study aimed to investigate the efficacy of DREZL and SDR for attenuating spasticity, and to compare efficacy between these two methods. Methods: All patients who underwent DREZL, SDR, or both for treatment of intractable spasticity caused by cerebral pathology at Siriraj Hospital during 2009 to 2016 were recruited. Severity of spasticity was assessed using Modified Ashworth Scale (MAS) and Adductor Tone Rating Scale (ATRS). Ambulatory status was also evaluated. Results: Fifteen patients (13 males) with a mean age of 30.3 ± 17.5 years were included. Eight, six, and one patient underwent DREZL, SDR, and combined cervical DREZL and lumbosacral SDR, respectively. Eight of ten patients with preoperative bed-bound status had postoperative improvement in ambulatory status. Spasticity was significantly reduced in the DREZL group ( p < 0.001), the SDR group ( p < 0.001), and in overall analysis ( p < 0.001). SDR was effective in both pediatric and adult spasticity patients. A significantly greater reduction in spasticity as assessed by MAS score ( p < 0.001) and ATRS score ( p = 0.015) was found in the DREZL group. Transient lower limb weakness was found in a patient who underwent SDR. Conclusions: DREZL is more effective for reducing spasticity, but is more destructive than SDR. DREZL should be preferred for bed-ridden patients, and SDR for ambulatory patients. Both operations are helpful for improving ambulatory status. Gait improvement was observed only in patients who underwent SDR. Adult patients with spasticity of cerebral origin benefit from SDR. [ABSTRACT FROM AUTHOR]

The computational complexity evaluation is necessary for software defined Forward Error Correction (FEC) decoders. However, currently there are a limited number of literatures concerning on the FEC complexity evaluation using analytical methods. In this paper, three high efficient coding schemes including Turbo, QC-LDPC and Convolutional code (CC) are investigated. The hardware-friendly decoding pseudo-codes are provided with explicit parallel execution and memory access procedure. For each step of the pseudo-codes, the parallelism and the operations in each processing element are given. Based on it the total amount of operations is derived. The comparison of the decoding complexity among these FEC algorithms is presented, and the percentage of each computation step is illustrated. The requirements for attaining the evaluated results and reference hardware platforms are provided. The benchmarks of state-of-the-art SDR platforms are compared with the proposed evaluations. The analytical FEC complexity results are beneficial for the design and optimization of high throughput software defined FEC decoding platforms. [ABSTRACT FROM AUTHOR]

The SCA 2.2.2 architecture has achieved widespread adoption in the military communications market. Hundreds of thousands of SCA enabled software defined radios (SDRs) have been deployed to date, and world-wide dozens of programs are working to field more of these types of radios. The reasons for this success are the benefits enabled through adoption of the SCA: proven cost and delivery time advantages, lower logistical overhead through enhanced inter-component interoperability, simplified insertion of new communications capabilities in deployed radios, enhanced coalition interoperability through portability of waveforms and reduced development risk. As a result of this success, new countries and new organizations have begun to explore the use of the SCA, driving a second generation of SDR market adoption. Successful deployment of SCA 2.2.2 based SDRs has identified improvements to be made to advance the technology further. The Wireless Innovation Forum is working in close collaboration with the U.S. Department of Defense Joint Tactical Networking Center (JTNC) to evolve the SCA. The resulting SCA 4.1 specification represents the future of defense SDR technology. [ABSTRACT FROM AUTHOR]

The Joint Tactical Radio System was the first major program that sought to develop a new family of radio systems using a software-based architecture. A new software-oriented architecture, the Software Communications Architecture was developed as a common, interoperable foundation for this new family of tactical radios. The fundamental objective was to enable radio systems to support multiple waveforms, allow for software-only upgrades of operational capabilities and ultimately reduce the tail-end logistics, maintenance and upgrade costs. However, within the first few years the program experienced difficulties and setbacks resulting in cost and schedule overruns. Several program reviews and analyses were performed to assess the reasons for the problems encountered. Although multiple causes were cited for the failures, this paper puts forth the assertion that a key aspect of the engineering process, systems engineering, was not planned into the program and a fundamental cause for many of the issues encountered. [ABSTRACT FROM AUTHOR]

Full duplex Cognitive Radio (CR) achieves more spectral efficiency if it operates in listen and talk mode. It also facilitates to find multiple free available spectrum in a wide band and fast frequency handoff in the case the secondary user uses the frequency occupied by the Primary User (PU). Full duplex CR works using two RF chain with employing the sensing by a dedicated RF chain and transmitting the data with other RF chain. The main challenge involved in full duplex sensing is the self-interference problem, particularly for energy detector based spectrum sensing. Energy detector based spectrum sensing is widely used because of less computational complexity and PU signal knowledge is not required which is an essential feature in wideband spectrum sensing. This work proposes an SDR implementation of full duplex CR using energy detector with self-interference cancellation using Wiener filter. The self-interference signal is predicted by Wiener filter and it is removed in the received signal before apply to the energy detector. The proposed scheme is simulated and validated through an experimental study on SDR platform. The results show the improvement in probability of detection of PU signal. Parallel and pipelined architectures are employed to implement the entire system using the Kintext 7 FPGA on NI USRP RIO 2943R SDR, which result in reduction of sensing time. [ABSTRACT FROM AUTHOR]

Green spectrum sharing techniques share the spectrum with minimum interference to the primary user with reduced transmit power at secondary. Usually, the green spectrum sharing is achieved by operating the cognitive radio in underlay mode by power control mechanism or MIMO cognitive radio based antenna selection mechanism. But the above approaches will not guarantee the Quality of Service (QoS) requirement of the secondary user. Interference Minimization and meeting the QoS requirement of secondary user is modeled as a multi objectives optimization problem and solved using genetic algorithm (GA) in this paper. MIMO cognitive radio system with the GA based power control, antenna selection, and link adaptation is proposed to share the spectrum with minimum interference to primary receiver and QoS assurance of the secondary user. QoS parameter considered under the works are the secondary user bit error rate, band efficiency, and data rate. The GA optimizes the parameters of antenna selection matrix, transmitter power, modulation type, modulation order, the roll-off factor of pulse shaping filter and symbol rate to achieve target QOS. The earlier convergence of the GA is another issue addressed in this work. The earlier convergence of GA results in a local optimum value of parameters, therefore, this work used the hybrid transform for the fitness of individual chromosome. The proposed work is carried out in real time using software defined radio (SDR) platform 6 GHz Vector Signal Generator 5673 configured as a secondary transmitter, Vector Signal Analyzer 5663 as the secondary receiver and two 2 × 2 MIMO USRP RIO SDR 2943R as a primary transmitter and receiver. [ABSTRACT FROM AUTHOR]

This paper introduces a software-defined radio implementation of an OFDM-based transceiver for the prototyping and testing of 5G physical layer algorithms. The implementation uses high level abstraction tools to develop and test the algorithms, significantly reducing the time and effort needed to test new features. The proposed architecture adopts interconnecting FIFOs between each functional block, reducing the critical paths and enabling complex designs to be implemented at higher clock rates. The proposed LTE-like transceiver is implemented using COTS FPGA and RF development boards. The real-time over-the-air demonstrator has an on-the-fly scalable bandwidth from 20 to 61.44 MHz, attaining close to 500 Mb/s when using 256-QAM modulation. [ABSTRACT FROM AUTHOR]

Improved spectral and energy efficiency are two key requirements for the next generation (5G) wireless communication systems. The inefficiency and non-linearity of traditional power amplifiers (PA) pose significant challenges to meet these requirements, especially for multicarrier modulation signals with high peak to average power ratio (PAPR). Orthogonal frequency division multiplexing (OFDM) is currently the most widely used multi carrier modulation technique; it has been adopted in many wireless communication standards including IEEE 802.11, 802.16, 3GPP Long Term Evolution and WiMAX. When a high PAPR signal process through a nonlinear power amplifier (PA), intermodulation distortion is generated, creating out-of-band emission that can interfere with other transmission in adjacent bands. In addition, in-band distortion, which degrades the bit error rate performance, occurs. Hence, I have addressed these problems by employing four different PAPR reduction techniques such as Phase modulation, Rail clipping, Sample and Hold approach and Threshold methods based on amplitude clipping. For practical proof of the proposed concepts, I have chosen software defined radio as an experimental setup that employs USRP N210 as hardware and GNU Radio as software. [ABSTRACT FROM AUTHOR]

The RecG protein of Escherichia coli is a double-stranded DNA translocase that unwinds a variety of branched substrates in vitro. Although initially associated with homologous recombination and DNA repair, studies of cells lacking RecG over the past 25 years have led to the suggestion that the protein might be multi-functional and associated with a number of additional cellular processes, including initiation of origin-independent DNA replication, the rescue of stalled or damaged replication forks, replication restart, stationary phase or stress-induced 'adaptive' mutations and most recently, naïve adaptation in CRISPR-Cas immunity. Here we discuss the possibility that many of the phenotypes of recG mutant cells that have led to this conclusion may stem from a single defect, namely the failure to prevent re-replication of the chromosome. We also present data indicating that this failure does indeed contribute substantially to the much-reduced recovery of recombinants in conjugational crosses with strains lacking both RecG and the RuvABC Holliday junction resolvase. [ABSTRACT FROM AUTHOR]

A transmission failure is caused by either signal attenuation, interference or both in wireless networks. Identification of such cause helps understanding of the current status of a wireless channel and network, thus providing essential information for optimizing the behavior of each network node as well as the operation of the whole network. In this paper, we propose a scheme to classify transmission failures in the receiver side (thus necessitating no change of existing protocols); the scheme detects an anomaly of the receive power pattern observed during an interference period and classify transmission events with the aid of a modem's decoding result. The feasibility of the scheme is shown via a real experiment with its SDR implementation based on IEEE 802.15.4 ZigBee. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to determine the outcomes for children who underwent selective dorsal rhizotomy (SDR) for the treatment of spasticity related to spinal pathology. Methods: We performed a retrospective review of all cases of SDR at our institution over the last 30 years and identified patients in whom spasticity was attributed to spinal rather than cerebral pathology. We gathered demographic information and recorded functional status and spasticity scores pre-operatively and over long-term follow-up. Results: We identified four patients who underwent SDR for spinal-related spasticity. All four had hereditary spastic paraparesis (HSP). All patients had reduced spasticity in the lower limbs after SDR, which was maintained over long-term follow-up. Two patients had a more severe and progressive subtype of HSP, and both these patients exhibited functional decline despite improvement in tone. Conclusions: Our findings suggest SDR is a reasonable option to consider for relief of spinal-related spasticity in uncomplicated hereditary spastic paraparesis. However, SDR for the treatment of complicated HSP seems to carry more risks and have a less predictable outcome. Overall, SDR is probably best reserved for pathologies that are relatively stable in their disease course. [ABSTRACT FROM AUTHOR]

Global navigation satellite systems (GNSSs) have been experiencing a rapid growth in recent years with the inclusion of Galileo and BeiDou navigation satellite systems. The existing GPS and GLONASS systems are also being modernized to better serve the current challenging applications under harsh signal conditions. Therefore, the research and development of GNSS receivers have been experiencing a new upsurge in view of multi-GNSS constellations. In this article, a multi-GNSS receiver design is presented in various processing stages for three different GNSS systems, namely, GPS, Galileo, and the Chinese BeiDou navigation satellite system (BDS). The developed multi-GNSS software-defined receiver performance is analyzed with real static data and utilizing a hardware signal simulator. The performance analysis is carried out for each individual system, and it is then compared against each possible multi-GNSS combination. The true multi-GNSS benefits are also highlighted via an urban scenario test carried out with the hardware signal simulator. In open sky tests, the horizontal 50 % error is approximately 3 m for GPS only, 1.8 to 2.8 m for combinations of any two systems, and 1.4 m when using GPS, Galileo, and BDS satellites. The vertical 50 % error reduces from 4.6 to 3.9 when using all the three systems compared to GPS only. In severe urban canyons, the position error for GPS only can be more than ten times larger, and the solution availability can be less than half of the availability for a multi-GNSS solution. [ABSTRACT FROM AUTHOR]

Key message : 2n pollen formed by FDR in citrus. Abstract: The Japanese local citrus cultivar, Nishiuchi Konatsu ( Citrus tamurana hort. ex Tanaka; NK hereafter), has the ability to produce unreduced 2n pollen grains, allowing generation of polyploid progenies via sexual polyploidization. In this study, we developed a method of single-pollen genotyping for citrus and applied it to the analysis of transmission of heterozygosity in NK 2n pollen grains. Heterozygosity transmission was expressed as the percentage inheritance of a set of heterozygous alleles from the parent to the 2n gamete. The pathway of 2n pollen development was investigated by applying the observed heterozygosity transmission and genetic distance to two different map functions, for first division restitution (FDR) and second division restitution (SDR). The fit of the values observed for both functions was calculated, while virtually moving the centromere position. We screened for six heterozygous SSR (codominant microsatellite marker loci) in NK, all of which were expected to lie within the same linkage group. Pollen germination prior to DNA extraction was essential for this work, and 6-h incubation proved to be optimal for subsequent PCR amplification. Single-pollen genotyping unreduced NK 2n pollen grains revealed that heterozygosity transmission exceeded 50 % in all six alleles, and fitness tests indicated that the FDR map function better fitted the heterozygosity transmission observed rather than the SDR function. Our data thus strongly indicate that 2n pollen in NK is a result of first division restitution. [ABSTRACT FROM AUTHOR]

0.1-3 GHz high isolation wideband CMOS Transmit/Receiver (T/R) switch is presented for software-defined radio (SDR) transceiver. The independent bias technique is proposed to keep the transistors in ideal ON/OFF mode to improve power handling capacity. The leakage cancellation technique with two matched paths is introduced to cancel the leakage from TX port to RX port. The proposed T/R switch has been implemented in 65 nm CMOS. The measured results show that the differential T/R switch achieves 23dBm 1-dB compression point (P) and features 50-70 dB isolation. [ABSTRACT FROM AUTHOR]

Automatic digital modulation recognition (ADMR) has become an interesting problem in wireless communication systems with various civil and military applications. In this paper, an ADMR algorithm is proposed for both orthogonal frequency division multiplexing and multi-carrier code division multiple access systems using discrete transforms and mel-frequency cepstral coefficients (MFCCs). The proposed algorithm uses one of the discrete cosine transform, discrete sine transform, and discrete wavelet transform with MFCCs to extract the modulated signal coefficients, and uses also either a support vector machine (SVM) or an artificial neural network (ANN) for modulation classification. Simulation results show that the proposed algorithm provides higher recognition rates than those obtained in previous studies, in addition to a superiority of SVM performance compared to ANN performance at low signal-to-noise ratios. [ABSTRACT FROM AUTHOR]