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Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Utilizing deep learning for data mining in biomedicine often falls short in leveraging prior knowledge and adapting to the complexities of biomedical literature mining. Entity recognition, a fundamental task in information extraction, also provides data support for Natural Language Processing (NLP) downstream tasks. Bovine Viral Diarrhea Virus (BVDV) results in considerable economic losses in the cattle industry due to calf diarrhea, bovine respiratory syndrome, and cow abortion. This study aims to extract information on BVDV from relevant literature and build a knowledge base. It enhances feature extraction in the BioBERT pre-trained model using the Machine Reading Comprehension (MRC) framework for information fusion and bi-directionally extracts corpus information through the Bi-LSTM network, followed by a CRF layer for decoding and prediction. The results show the construction of a BVDV Corpus with 22 biomedical entities and introduce the BioBERT-Bi-LSTM-CRF Integrated with MRC (BBCM) model for Named Entity Recognition (NER), combining prior knowledge and the reading comprehension framework (MRC). The BBCM model achieves F 1 -scores of 78.79% and 76.3% on the public datasets JNLPBA and GENIA, respectively, and 67.52% on the BVDV Corpus, outperforming other models. This research presents a targeted NER method for BVDV, effectively identifying related entities and exploring their relationships, thus providing valuable data support for NLP's downstream tasks. [ABSTRACT FROM AUTHOR]

Machine Reading Comprehension (MRC) is a task that enables machines to mirror key cognitive processes involving reading, comprehending a text passage, and answering questions about it. There has been significant progress in this task for English in recent years, where recent systems not only surpassed human-level performance but also demonstrated advancements in emulating complex human cognitive processes. However, the development of Arabic MRC has not kept pace due to language challenges and the lack of large-scale, high-quality datasets. Existing datasets are either small, low quality or released as a part of large multilingual corpora. We present the Arabic Question Answering Dataset (ArQuaD), a large MRC dataset for the Arabic language. The dataset comprises 16,020 questions posed by language experts on passages extracted from Arabic Wikipedia articles, where the answer to each question is a text segment from the corresponding reading passage. Besides providing various dataset analyses, we fine-tuned several pre-trained language models to obtain benchmark results. Among the compared methods, AraBERTv0.2-large achieved the best performance with an exact match of 68.95% and an F1-score of 87.15%. However, the significantly higher performance observed in human evaluations (exact match of 86% and F1-score of 95.5%) suggests a significant margin of possible improvement in future research. We release the dataset publicly at https://github.com/RashaMObeidat/ArQuAD to encourage further development of language-aware MRC models for the Arabic language. [ABSTRACT FROM AUTHOR]

To better combat the devastation of the protected forests in Côte d'Ivoire, a study was conducted to create a technique for detecting the acoustic signals produced by chainsaws deployed to fell trees in these areas. To improve the recognition rate of chainsaw sounds in a forest environment and increase the detection range of the recognition system, we are implementing the maximum ratio combining (MRC) technique on a microphone array. Therefore, the employment of an identification system is compared using one (01) microphone against the outcomes obtained by adopting system with three (03), six (06), and twelve (12) microphones. The use of MRC is then contrasted with an alternative recombining approach, designated as simple summation (SS). The SS is characterised by the simple addition of the signals acquired by the microphone array in the frequency domain. The MRC was employed on various microphone arrangements, accounting for varying degrees of attenuation experienced by chainsaw sounds. The K-Nearest Neighbors, in combination with Mel Frequency Cepstral Coefficients (MFCC), was employed to detect chainsaw sounds within the 16 kHz central frequency octave band. MRC applied to microphone arrays provided superior outcomes than simple summation. The enhancement in terms of classification rate ranged from [18; 51], favouring MRC. Moreover, it extended the chainsaw detection range from 520 m (using one microphone) to 1210 m (using a 12-microphone array). Taking into account the criteria for selecting an optimum microphone array, including classification rate, number of microphone nodes, information processing time and detection range, the six-microphone array was chosen as the best configuration. This configuration boasts a theoretical detection range of 1040 meters. [ABSTRACT FROM AUTHOR]

The deployment of cooperative communication inside a cell-Free mMIMO system can improve both the spectral efficiency SE performance as well as the energy efficiency EE performance. This increase is due to the increase in the signal to interference plus noise ratio SINR. In fact, the SINR can be greatly improved when the cognitive radio theory is applied due to its capability of interference mitigation. In this manuscript, the cognitive intelligent reflecting surfaces IRSs are distributed inside a cell-Free mMIMO system in order to improve the SE as well as the EE performance. Moreover, the cognitive radio can raise each user SINR. In this manuscript, the authors try to carry out the suitable mathematical model for the fore-mentioned system. Moreover, the system will be simulated. Subsequently, the simulation results will be explained. It is obvious that the implantation of cognitive IRSs inside, cell-Free mMIMO systems can greatly increase the system performance. [ABSTRACT FROM AUTHOR]

Machine reading comprehension is introduced to improve machines' readability and understandability of human languages. This sophisticated version of natural language processing is used for testing and improving the machine's efficiency for reading and responding to the input texts for appropriate queries. In this article, a persistent comprehensive model using query reconstruction is introduced to address the "Cloze Style" issue in text reading. This issue results in multiple output delivery that serves as irrelevant for different input queries. Therefore, the query reconstruction using the possible combination, reducing the aforementioned issue, is introduced in this model. The possible query keywords are replaced using the maximum individual combinations. The combinations are swapped using deep learning through keyword training and substitution processes. This process is persistent until the maximum text output (answer/ response) is obtained from the machine. The output is used for analyzing the understandability of the machine based on which the training intensity is tuned for successive iterations. Therefore, the proposed model scrutinizes output accuracy by reducing errors under controlled combination time. [ABSTRACT FROM AUTHOR]

Implementation of an eRehabilitation intervention named Fit After Stroke @Home (Fast@home) – including cognitive/physical exercise applications, activity-tracking, psycho-education – after stroke resulted in health-related improvements. This study investigated what worked and why in the implementation. Implementation activities (information provision, integration of Fast@home, instruction and motivation) were performed for 14 months and evaluated, using the Medical Research Council framework for process evaluations which consists of three evaluation domains (implementation, mechanisms of impact and contextual factors). Implementation activities were evaluated by field notes/surveys/user data, it's mechanisms of impact by surveys and contextual factors by field notes/interviews among 11 professionals. Surveys were conducted among 51 professionals and 73 patients. User data (n = 165 patients) were extracted from the eRehabilitation applications. Implementation activities were executed as planned. Of the professionals trained to deliver the intervention (33 of 51), 25 (75.8%) delivered it. Of the 165 patients, 82 (49.7%) were registered for Fast@home, with 54 patient (65.8%) using it. Mechanisms of impact showed that professionals and patients were equally satisfied with implementation activities (median score 7.0 [IQR 6.0–7.75] versus 7.0 [6.0–7.5]), but patients were more satisfied with the intervention (8.0 [IQR 7.0–8.0] versus 5.5 [4.0–7.0]). Guidance by professionals was seen as most impactful for implementation by patients and support of clinical champions and time given for training by professionals. Professionals rated the integration of Fast@home as insufficient. Contextual factors (financial cutbacks and technical setbacks) hampered the implementation. Main improvements of the implementation of eRehabilitation are related to professionals' perceptions of the intervention, integration of eRehabilitation and contextual factors. To increase the use of eRehabilitation by patients, patients should be supported by their healthcare professional in their first time use and during the rehabilitation process. To increase the use of eRehabilitation by healthcare professionals, healthcare professionals should be (1) supported by a clinical champion and (2) provided with sufficient time for learning to work and getting familiar with the eRehabilitation program. Integration of eRehabilitation in conventional stroke rehabilitation (optimal blended care) is an important challenge and a prerequisite for the implementation of eRehabilitation in the clinical setting. [ABSTRACT FROM AUTHOR]

In an advanced wireless communication system, a smart receiver trims down the fading effect. From a practical point of view, performance such receiver depends not only on the estimation of channels but also system accuracy. This paper derives the general expression of average bit error rate (BER) and outage probability for dual-branch Maximum Ratio Combining (2-MRC) over Fluctuating Two Ray (FTR) fading channels with Imperfect Channel Estimation. Communication channels encountered in Fifth-Generation Millimeter-Wave communication is represented accurately by the FTR fading channels. A 2-MRC receiver is considered because of its performance advantage and less complexity. The probability density function of the output signal-to-noise ratio is obtained for 2-MRC receiver with channel estimation error over the FTR fading model. The mathematical description of average BER for both non-coherent and binary coherent modulation is derived. The impact of the fading parameters and the error estimation on the system efficiency are assessed through numerical analysis of the generated equations. [ABSTRACT FROM AUTHOR]

Towards the 5Gnetworks and beyond, there are a lot of emerging technologies. These technologies include but not limited to; multiple input multiple output (MIMO), cell-Free networks, and millimeter wave bands. The cellular MIMO can provide a satisfied performance for users except the shadowed and the cell-edge ones. In order to overcome this disadvantage, the cell-Free networks are deployed. Through applications of distributed access points (APs), the cell-Free networks can provide a ubiquitous coverage for users as whole. Therefore, they can provide a high throughput for users. Moreover, the applications of millimeter wave bands can provide a high bandwidth and hence, a high throughput for users. In other words, the application of the cell-Free technology combined with the millimeter wave bands can extremely enlarge the users' throughput. This is the motivation of our manuscript. The purpose of this manuscript is to provide mathematical model and simulation for the cell-Free mMIMO network, operating in the millimeter wave bands. The performance metrics can include; the spectral efficiency (SE), bit error rate (BER), and energy efficiency (EE). It is observed that the centralized cooperation among the APs can let users have a satisfied throughput even the system employs the maximal ratio combining (MRC). Furthermore, all cooperation levels, among APs, can perform well even for non-light of sight (NLOS) environment. [ABSTRACT FROM AUTHOR]

The implementation of massive multiple input multiple output systems mMIMO can greatly enhance the spectral efficiency SE performance for users. Although, the cell-edge users as well as indoor users still have a bad performance. The cell-Free network, wherein the large number of existing antennas is replaced by the same number of distributed access points APs, can enlarge the SE performance even for shadowed users. The performance can be further enhanced after application of cooperation. When a Cell-Free mMIMO system is enriched with intelligent reflecting surfaces IRS, its performance may be improved. In this manuscript, the authors will carry out the mathematical model and simulation for the Cell-Free networks employing IRSs. The performance metrics can include the SE as well as energy efficiency EE. From the simulation results, it can be observed that implementation of IRSs inside the cell-Free networks can greatly increase the SE and EE of the system. [ABSTRACT FROM AUTHOR]

Passive radar is an interesting approach in the context of non-cooperative target detection. Because the signal source takes advantage of the so-called illuminator of opportunity (IoO), the deployed system is silent, allowing the operator cheap, portable, and practically undetectable deployments. These systems match perfectly with the use of antenna arrays to take advantage of the additional gains provided by the coherent combination of the signals received at each element. To obtain these benefits, linear processing methods are required to enhance the system's performance. In this work, we summarize the main beamforming methods in the literature to provide a clear picture of the current state of the art. Next, we perform an analysis of the benefits and drawbacks and explore the chance of increasing the number of antenna elements. Finally, we identify the major challenges to be addressed by researchers in the future. [ABSTRACT FROM AUTHOR]

Copyright of Advancements of Microbiology is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the remote sensing monitoring of conservation tillage, the acquisition of remote sensing data with high spatial and temporal resolution is critical. The current optical remote sensing images cannot realize both temporal and spatial resolution, especially under cloud and rain interference. Thus, this study employs the enhanced spatial and temporal adaptive reflectance fusion model (ESTARFM) to obtain the normalized difference tillage index (NDTI) with both temporal and spatial resolution estimated by Sentinel−2 and MODIS using the Index−then−Blend (IB) and Blend−then−Index (BI) fusion schemes. After comparison, the IB scheme was better than the BI scheme in predicting results and prediction efficiency. The NDTI predicted by ESTARFM and Sentinel−2 on June 12, 2020 was compared. A coefficient of determination R2 of 0.73 and RMSE of 0.000117 was obtained, indicating a high prediction accuracy, which meets the prediction requirements. Based on the predicted ESTARFM NDTI of the study area on May 17, 2021, the maize residue cover (MRC) of the study area was estimated using the previously constructed MRC unary linear regression model. The MRC of the sampling points of the remote sensing images was estimated by verifying the predicted ESTARFM NDTI with the MRC of the sampling points taken in the field extracted by the maximum likelihood classifier, which has a coefficient of determination R2 of 0.78 and RMSE of 0.00676, signifying better prediction results. The proposed method provides considerable data sources for the remote sensing monitoring studies of conservation tillage. [ABSTRACT FROM AUTHOR]

Background: chronic idiopathic demyelinating polyneuropathy (CIDP) is an acquired, immune-mediated neuropathy characterized by weakness, sensory symptoms and significant reduction or loss of deep tendon reflexes evolving over 2 months at least, associated with electrophysiological evidence of peripheral nerve demyelination. Recently, subcutaneous immunoglobulins (SCIg) have been introduced in clinical practice as a maintenance therapy for CIDP; nevertheless, electrophysiological and efficacy data are limited. Methods: to evaluate SCIg treatment efficacy, we retrospectively reviewed data from 15 CIDP patients referring to our clinic, receiving SCIg treatment and who performed electrophysiological studies (NCS) and clinical scores (MRC sumscore, INCAT disability score and ISS) before starting the treatment and at least one year after. Results: NCS showed no significant changes before and during treatment for all the nerves explored. Clinical scores did not significantly change between evaluations. Correlation analysis evidenced a positive correlation of cMAPs distal amplitude with MRC sumscore and a trend of negative correlation with the INCAT disability score. Conclusions: SCIg maintenance therapy preserves nerve function in CIDP with a good efficacy and safety. Treatment effectiveness can be assessed with ENG, which represents a useful instrument in the follow-up and prognostic assessment of CIDP. [ABSTRACT FROM AUTHOR]

Background: Hand tendon reconstruction is required in both acute and chronic tendon injuries. A number of donor sites have been described; one such novel donor site is semitendinosus tendon used a graft for hand tendon reconstruction. Based on data reviewed, only a few cases are described up till now. Objective: Utility of semitendinosus tendon graft with adequacy of tendon material for hand tendon reconstruction and minimal donor site morbidity Methods: Semitendinosus tendon was utilized in total of 18 patients undergoing tendon reconstruction for chronic tendon injuries and for tendon transfer to achieve adequate length. All cases were performed during January 2019 To December 2020. Full length uni/bilateral semi-tendinosus tendon was harvested using a tendon harvester. Tendon was used as a single slip or was split into further slips as needed for tendon reconstruction. Post operatively splints were continued as per protocol (keeping splint for 6 weeks, encouraging active physiotherapy at 8 weeks, continuing night splintage for total of 10 weeks and advising patient to avoid lifting heavy weight for at least 12 weeks). Patients were followed with assessment of strength via MRC (Medical Research Council) grading scale, and tendon excursion measurements via tip to palm distance. Results: Patients had a mean age for 27.5±2.3 with a predominant male population (72.2%). Post-operative assessment showed finger strength of MRC 5 in twelve patients and MRC 4 in three and MRC 3 in three patients. Tendon excursion was documented measuring a tip to palm distance. Three patients developed tendon adhesions which were treated with tenolysis. Conclusion: Semitendinosus is a recommended option for hand tendon (both flexor & extensor) reconstruction, providing adequate length & strength for reconstruction with high predictable availability and reliability. Although Palmaris longus remains the recommended option for single tendon reconstruction, it is absent in a few cases or is rudimentary, making it difficult to be utilized. [ABSTRACT FROM AUTHOR]

The cell-Free massive multiple input multiple output "mMIMO" networks can provide a satisfied performance for the fifth generation "5G" systems and beyond even there are shadowed users or indoor ones. The performance of the cell-Free mMIMO systems was mathematically analyzed and simulated in a lot of previous works. However, this work aims to provide a complete mathematical model and simulation for a cell-Free mMIMO system that applies relays which operate with the cognitive radio theory. The proposed work can provide novel contributions on two axes. Firstly, the relays can improve the coverage performance of a cell-Free mMIMO network especially at shadowed users, indoor users, and the cell-edge ones. Secondly, the cognitive radio can mitigate the interference in a cell-Free mMIMO network. The interference mitigation results in performance enhancement. Therefore, the cell-Free mMIMO network, based on cognitive relays, is studied. The proposed system is mathematically analyzed and simulated. The spectral efficiency "SE" and signal to interference plus noise ratio "SINR" is deduced. They are given in a closed form formula. It can be concluded that the cognitive relays can improve; SINR, SE, and Energy Efficiency "EE" of a cell-Free mMIMO system. [ABSTRACT FROM AUTHOR]

Olga Kennard (née Weisz, 1924–2023) was a true pioneer in crystallography. She left a lasting mark on scientific research with the establishment of the Cambridge Crystallographic Data Centre (CCDC). [ABSTRACT FROM AUTHOR]

In this study, the authors provide a direct comparison made between whole tree-harvesting (WTH) and cut-to length (CTL) methods, which was conducted in two sites in the Slovak Republic and applied to poplar plantations. Both systems, WTH and CTL, have been employed at the highest mechanization level in two sites: "Nivky" and "Skalica". Two different strategies, namely, "mass handling" and "small-scale mechanization", have been used for WTH and CTL, respectively. The study results showed that the level of productivity (ODT SMH−1) in the felling operation was almost double for WTH than for the CTL method in Nivky (+84%) and more than double in Skalica (+113%). The extraction operation under WTH showed a productivity increase from one fifth (+20%) to more than double (104%) that of the CTL method in the Nivky and Skalica sites, respectively. Regarding cost-efficiency (EUR ODT−1), the WTH system offers a similar trend except with respect to extraction in Nivky (higher productivity site), in which the CTL extraction was 4.5% less expensive than the WTH extraction. The study results show that the mass-handling technique deployed in the WTH system offers very good performance in poorer plantations since the very small tree size and low-growing stock challenge the CTL system more than the WTH system. The total operation (felling, bucking, and extraction) costs (EUR ODT−1) recorded by the study in commercial conditions (as contractors perform for revenue purposes) were 32.50 and 45.80 EUR ODT−1 for CTL and 43.30 and 53.60 EUR ODT−1 for WTH for the higher-yield site (Nivky) and lower-yield site (Skalica), respectively. Regarding the WTH System, the researchers found that the drop in efficiency (and the consequent rise in the costs-per-ton of product) depends largely on the bucking phase conducted using the harvester at the landing of the stacked piles of interlocked trees. The main results of this study demonstrate the promising strategy of mass handling associated with the WTH system in medium rotation coppice (MRC) harvesting and shows that bucking is the weaker phase. Future efforts must be made to ensure feasibility of the "mass handling" strategy alongside the entire workflow by means of finding suitable mobile machinery that can delimb, debark, and crosscut tree bunches instead of single trees. [ABSTRACT FROM AUTHOR]

Mulberry (Morus species) leaves are the sole source of food for the silkworm (Bombyx mori L.) hence, high-quality foliage is the key to the productivity of the silk industry. Rapid water loss from the harvested leaves is one of the major reasons for quality loss affecting silkworm feeding behaviour. Previous research in our laboratory indicated that epicuticular wax is essential in maintaining leaf moisture in harvested leaves of mulberry. In the present study, an agronomic approach was designed and tested to increase the cuticular resistance and enhance moisture retention capacity in the harvested leaves in two genotypes of mulberry, Dudia white (DW) and Matigara white (MW). Controlled irrigation and mild drought stress increased leaf epicuticular wax and drought-stressed plants had a significantly higher wax load (465.31 and 556.29 μg dm-2 in Dudia white and Matigara white, respectively) at 40 per cent soil field capacity (FC) when compared to the plants grown at 100 per cent FC. The harvested leaves showed higher moisture retention capacity (MRC) of 92 and 84.74 per cent at 40 per cent FC compared to 62.55 and 57.10 per cent at 100 per cent FC in Dudia white and Matigara white, respectively. Leaves from water-limited plants had significantly lower water loss of 3.4 and 5.9 per cent under 40 per cent FC compared to control plants (6.6 and 9.1%). The technique used in this study increased MRC and helped in preserving leaf quality. The approach developed is cost-effective and can be easily adopted in farmer’s fields. [ABSTRACT FROM AUTHOR]

In this paper, we have formulated a novel expression of the probability density function (PDF) of the L-MRC receiver over correlated η − μ channel considering the existing error in the estimation of the channel coefficients. The derived PDF is used to calculate the average bit error rate of the Quadrature Amplitude Modulation (QAM) scheme and further performance analysis of the receiver has been done with respect to this modulation. The performance of the receiver in terms of different channel and receiver performance parameters has been plotted and discussed in the results section. The results are verified with the help of the Monte Carlo simulation. [ABSTRACT FROM AUTHOR]

This paper develops three low-complexity detection schemes for the spatial modulation (SM) Multiple Input Multiple Output (MIMO) systems. We first propose a reduced complexity maximum likelihood (RC-ML) detection scheme. For the practical values of the modulation index, the proposed RC-ML method is simpler than the existing hard-limiting-based ML schemes. The two other proposals are based on a suboptimal Maximum Ratio Combining (MRC) detection method. We present a new analysis of the MRC detector in the uncorrelated Rayleigh fading channel and identify the system operational scenarios for which the MRC performance is nearly identical to the ML performance. Our proposals — a hybrid MRC-ML method and an MRC scheme with rank reduction — are inspired by this analysis. The analytical and simulation results show that the proposed MRC-based schemes can attain a near-optimal performance while reducing the complexity of the ML-based SM receiver. [ABSTRACT FROM AUTHOR]

Cellular networks have been evolving at a great pace recently to keep up with the rapidly increasing demand for wireless data services. To cater for this demand, advanced technologies will be implemented in the next generation of cellular network. A promising technology, known as Massive Multiple-Input Multiple-Output (MIMO), will satisfy the high data rate requirement of wireless services. The concept of massive MIMO is based on installing hundreds or thousands of antenna elements at the BS and only one antenna at the user terminal. The beneficial effect of employing such large antenna elements is that unprecedented antenna gains and a spatial resolution that allows multi-user massive MIMO communication to a large number of users per cell can be obtained while maintaining robustness to inter-user interferences. The problem of finding theoretical sum-rate and efficiency under imperfect CSI (Channel State Information) for each mobile user that matches closely to realistic 5G models reduces to the application of these theoretical analysis to practical 5G spatial model with both the Line-Of-Sight and Non-LOS propagation paths. To this end, we propose a solution to this problem by applying an uplink theoretical analysis of a Multi-User massive MIMO system under imperfect CSI, with multiple cells, to the 5G spatial channel model. Also, we formulate an optimization problem for our analysis and maximize the spectral efficiency per unit cell of the massive MIMO system. In this paper, two commonly used linear receivers namely the Maximum Ratio Combining and Zero-Forcing (ZF) are considered. The Signal and Noise Interference Ratio analysis for our proposed Multi-User massive MIMO system is described and closed-form expressions are derived for the sum-rate, spectral and energy efficiencies for each mobile user with random displacement in the multi-cell network. Our analysis takes into account the effect of inter-cell interference. It is shown through simulations that with only 200 BS antennas a Zero Forcing (ZF) receiver, under maximum inter-cell interference, can attain an uplink spectral efficiency of around 76 bps/Hz/cell for the 5G spatial channel whilst for the uncorrelated Rayleigh channel case this figure drops drastically to around 20 bps/Hz/cell. [ABSTRACT FROM AUTHOR]

Numerous devices are expected to upsurge profoundly in the proximate future with an estimated figure exceeding the 50 billion benchmark of connected devices by 2020. There are some rudimentary demands of the subscribers like system capacity, improved data rates with reduction in the latency and secure transmission of data in an unsecured media and to meet these demands, the cellular network has to go under suitable progression. As a building prospective for fulfilling these demands, to overcome the threats and challenges in the transmission of the data and to provide security to the information from the possible attacks, 5G is emerging as an optimal solution. For the demands of the tremendous count of subscribers, Device-to-Device Wireless Communication Network is an operative technology. The escalating content sharing amongst the users has been resulting in an exponential intensification in the wireless data traffic, coercing networks of cellular users to experience a suitable cataclysm. For allocating the resources to the Cellular Users under an attack scenario, numerous advances have been made till now. In this paper, an adaptive resource block allocation algorithm using HMM with beamforming approach has been projected to achieve high values of secrecy rate and low secrecy outage probability in 5G Wireless Communication Networks with the consideration of different applications demanded by Cellular Users and the priority of the applications (video, voice and data) in accord with enhanced Quality of Service of the channel. As the study of inherent secrecy rate for secure transmission of data in Wireless Communication Networks, random techniques are currently in great interest over the communication field. In this paper, it is to explore a multi-user scenario demanding different applications from BS under threat scenario of multi- eavesdropper. In this paper, different types of Beamforming are studied and different techniques involved for secure communication. An architecture has been provided for the security aspect in accordance with beamforming approach. As for better channel capacity, beamforming approach with diversity is an optimal solution for the secure transmission of information for Next Generation Networks. [ABSTRACT FROM AUTHOR]

One of the motivations towards the 5G cellular networks and beyond is the large increase in the supported data rate in both uplink and downlink. Deployment of small size cells, massive MIMO, wherein a large number of antennas are deployed at transmitters and receiver, are effective tools in these networks. Users under cell massive MIMO networks "mMIMO" can provide high data rate. However, the cell-edge user and users, under shadowing, can have a poor performance. Cell-Free networks can provide a satisfied data rate even for shadowed and cell-edge users. In this paper, cell-Free mMIMO networks are mathematically analyzed applying different cooperation mechanisms among the access points APs. Moreover, a new mathematical formula for the throughput, based on BER, is derived. Furthermore, closed formulas for the throughput-BER as well as energy efficiency (EE) performance are derived. Finally, the cognitive radio concept is proposed in order to limit the interference among users accessing the same resources in uplink. Simulation results show that the fully centralized cell-Free mMIMO network has a higher spectral efficiency and energy efficiency than the cellular mMIMO networks at different BER values especially when MMSE is applied. Furthermore, the cognitive radio theory can increase the SE and EE performance of the cell-Free networks when all cooperation mechanisms are applied. [ABSTRACT FROM AUTHOR]

Efficient wireless power transmission to a designated location can reduce the size of implantable device and save source energy, but the receiver coil and rectifier circuit still occupy a large area. This paper proposes a novel magnetic resonant coupling (MRC)-based double figure-of-eight coil sensor system to induce and monitor heat. Implantable devices could obtain energy from the surrounding electric field or heating effect. The fundamental of generating the heating effect by the proposed coil-based sensor system is derived, and conceptual system architecture is built. Then the radiating coil is analyzed in terms of Litz-wire coil optimization, lumped parameter extraction, impedance-matching network, equivalent circuit model, and coupling coefficient. Considering the current ratio, operating frequency, and designated location, the triple-mode operation mechanism is analyzed for the first time to adjust superposed electromagnetic fields at the designated location. At the odd-mode resonance, the electric field intensity in the middle between two figure-of-eight coils is significantly improved. Finally, the physical prototype of proposed coil-based sensor system is built up and experiments are conducted to test the currents in both figure-of-eight coils as well as the induced voltage and temperature change in the in-vitro sample by using the electrode sensor and thermocouple sensor. Measurements validate the feasibility of the proposed coil-sensor system. It also provides essential guidance on designing sensors for deep-tissue stimulation and hyperthermia treatment. [ABSTRACT FROM AUTHOR]

In this paper, the average symbol error rate (ASER) with rectangular quadrature amplitude modulation (RQAM) scheme has been analyzed over Rayleigh fading channels considering exponential correlation among the input branches of an MRC receiver. Exponential correlation is noticed by the antennas placed in a linear array at the receiver. The effect of correlation on the ASER for various levels of fading parameter as well as with different diversity order has been observed. [ABSTRACT FROM AUTHOR]

We study the performance of applying maximal ratio combining (MRC) in a single-input-multiple-output (SIMO) system with a Poisson field of interferers. Due to the correlated interference powers across different antennas, the derivation of the exact outage probability is highly involved. To tackle this problem, we take advantage of the mathematical property of the sub-Gaussian $\alpha $ -stable interference signal vector, and then derive an analytical lower bound of the outage probability, which is shown to be very tight through Monte Carlo simulations. Our results can be used to assist performance analysis and design of SIMO MRC receiver with random interferers. [ABSTRACT FROM AUTHOR]

Recent years have witnessed an incipient shift in science policy from a focus mainly on academic excellence to a focus that also takes into account "societal impact". This shift raises the question as to whether medical research has given proper attention to the diseases imposing the greatest burden on society. Therefore, with the aim of identifying correlations between research funding priorities and public demand in health, we examine grants issued by the major medical research funding bodies of China and the UK during 2006–2017 and compare the focus of their funded projects with the diseases that carry the highest burden of death, risk, or loss of health. The results indicate that the funding decisions of both nations do correspond to the illnesses with the highest health impact on their citizens. For both regions, the greatest health concerns surround non-communicable diseases, and neoplasms and cardiovascular disease in particular. In China, national health priorities have remained focused on these illnesses for the benefit of its own population, whereas the UK has funded a wider variety of research, extending to projects with impacts outside its borders to some developing countries. Additionally, despite an increased incidence of mental illness and HIV/AIDs in China, there is evidence that less priority has been given to these conditions. Both of these health areas seem to require more attention from China's national funding agencies and the society in general. Methodologically, this study can serve as an example of how to conduct analyses related to public health issues by combining informetric methods and data with the tools and data from other fields, thereby inspiring other scientometrics studies. [ABSTRACT FROM AUTHOR]

Background: Stroke can affect any portion of the central nervous system leading to a wide variety of symptoms depending on the part that is involved. Diffusion tensor imaging (DTI) is an emerging neuroimaging technique that allows measuring the integrity of white matter tracts. Objectives: The objective of this study is to find out if the diffusion tensor tractography technique can provide prognostic information regarding clinical outcome following ischemic stroke. Subjects and methods: Forty patients with acute ischemic stroke were studied with DTI. Size of infraction, degree of reduction of fractional anisotropy (FA), and pattern of corticospinal tract (CST) affection were identified. We assessed our patients according to the National Institute of Health Stroke Scale (NIHSS) and Medical Research Council (MRC) scale at onset of stroke and 3 months later. Results: FA reduction was correlated with MRC and NIHSS on admission (P < 0.001, 0.004 respectively) and after 3 months (P < 0.001, 0.013 respectively). The pattern of CST affection was associated with NIHSS and MRC after 3 months (P = 0.035, 0.001 respectively). Conclusion: DTI may be an indirect indicator of the ischemic stroke outcome. [ABSTRACT FROM AUTHOR]

This paper considers power domain based multiple access (PDMA) in cognitive radio network to serve numerous users who intend to multiple access to core network. In particular, we investigate the effect of signal combination scheme equipped at PDMA end-users as existence of direct link and relay link. This system model using relay scheme provides performance improvement on the outage probability of two PDMA end-users. We first propose a simple scheme of fixed power allocation to PDMA users who exhibit performance gap and fairness. Inspired by PDMA strategy, we then find signal to noise ratio (SNR) to detect separated signal for each user. In addition, the exact expressions of outage probability are derived in assumption that receiver can cancel out the interference completely with successive interference cancellation (SIC). By exploiting theoretical and simulation results, both considered combination schemes (Maximal Ratio Combining (MRC) and Selection Combining (SC) can achieve improved performance of two PDMA users significantly. [ABSTRACT FROM AUTHOR]

The main aim of this article is to analyse the role of the Lancang-Mekong Cooperation (LMC)) and to explore current milestones and challenges in the context of regional water cooperation. The LMC represents a specific form of a sub-regional platform which has been established in 2016 by China's government. The purpose of this intergovernmental organization is to promote regional cooperation between six riparian states (China, Myanmar, Thailand, Laos, Cambodia and Vietnam) and ensure sustainable development of the Lancang-Mekong Sub-region. The results show that despite the LMC does not meet all the criteria to become a proper River Basin Organization (RBO), it still remains highly progressive and widely popular among the riparian states. Currently, according to RBOs database from Oregon State University (2019) there can be identified only three inter-basin RBOs which together ensure transboundary water cooperation in Southeast Asia. The author concludes that despite the LMC offering many opportunities for further river development, the LMC still did not reach its full potential and face several challenges. Data has been collected by process-tracing analysis of official documents and from secondary literature related to the LMC and Mekong River development. The author applied the concept of multi-track water diplomacy and compare the current performance of the LMC with other RBOs to illustrate the role of RBOs in TWM. The findings of this article therefore can be applied to other case studies where RBOs possess a strong position in shaping TWM and where China builds up viable regional cooperation. [ABSTRACT FROM AUTHOR]

Résumé: Le pharmacien d'officine est reconnu comme un acteur de la prévention et de l'éducation thérapeutique. Un projet pédagogique mené dans les officines du Nord-Pas-de-Calais et coordonné par la faculté de pharmacie de Lille avec le réseau Néphronor nous a permis de collecter des données permettant d'évaluer l'intérêt d'une évaluation pharmaceutique officinale de la MRC. Nous rapportons ici le résultat de l'intervention réalisée dans 109 pharmacies d'officine. Les entretiens pharmaceutiques ont concerné 2 populations de patients. Le groupe A concerne des patients se connaissant porteurs d'une IRC (entretien pharmaceutique d'optimisation thérapeutique). Le groupe B regroupe des patients à risque de MRC pour lesquels est proposée une stratégie de dépistage. Ainsi, 354 patients ont été inclus dans le groupe A, majoritairement des femmes (51,2 %), en stade 3 d'IRC, d'âge moyen 73 ans, diabétiques (44 %). Environ 70 % des patients avaient déjà été vus par un néphrologue et 45 % d'entre eux présentaient une bonne adhésion thérapeutique selon le questionnaire de Morisky Green. Par ailleurs, 20 % des patients n'avaient pas de traitement néphroprotecteur en stades 3 et 4 de la MRC et plus de la moitié ne connaissaient pas les situations à risque d'insuffisance rénale aiguë. Le groupe B a inclus 532 patients (âge moyen 70 ans). L'intervention pharmaceutique a permis de dépister 10 % de patients avec un DFG < 60 mL/min/1,73 m2. L'entretien pharmaceutique en officine a permis d'optimiser la prise en charge thérapeutique et l'information des patients IRC, ainsi que le dépistage précoce chez certains patients à risque. Chronic kidney disease (CKD) is a major concern of public health. The pharmacist is known as a health practitioner involved in prevention and therapeutic education. Our study aimed at defining the impact of community pharmacists' interventions for preventing and screening CKD. In our observational prospective study of 5 months conducted in 109 community pharmacy, we included 2 groups of patients: A (therapeutic optimization): CKD patients and B (CKD screening): population at risk. In group A, we included 354 patients, mainly women (51.2%), in stage 3 of CKD, mean age 73 years old, with hypertension alone (40.6%) or associated with diabetes (44%). About 70% of the patients had a follow up by a nephrologist and 45% of them were good adherent according to the Morisky Green self-report. However, approximately 20% of patients did not have nephroprotective treatments in their regimen although they were on stage 3 or 4 CKD patients, and about half of them were not aware of medical situations at risk. Concerning group B, 532 patients were included. The pharmaceutical interventions screened 10 % of patients with a GFR < 60 mL/min/1.73m2. The community pharmacists' interventions helped to optimize the therapeutic management of CKD patients and in the early screening of patients at risk. More studies are needed to extrapolate our observations to a larger population. [ABSTRACT FROM AUTHOR]

Channel estimation is an essential component, in which channel state information playing very important role in wireless communications. But acquiring CSI in practice is a challenging issue for massive MIMO systems. To reduce the over burden for obtaining channel impulse response of huge Multi input multi output system channel reciprocity in TDD domain is suggested, because the forward link channel data can be derived from the reverse link signal without any feedback involvement. Because of mismatches at uplink, downlink channels maintaining reciprocity in TDD systems is impractical. We study the impact of multiplicative reciprocity error for precoders (Zero forcing, MMSE and MRT) performance along with channel estimation error. In this paper effect of RF mismatches impact on linear precoders is analyzed and simulated in terms of SINR versus SNR under additive white Gaussian noise. [ABSTRACT FROM AUTHOR]

This paper analyses the performance of filter bank multicarrier (FBMC) signaling in conjunction with offset quadrature amplitude modulation (OQAM) in multi-user (MU) massive multiple-input multiple-output (MIMO) systems. Initially, closed form expressions are derived for tight lower bounds corresponding to the achievable uplink sum-rates for FBMC-based single-cell MU massive MIMO systems relying on maximum ratio combining (MRC), zero forcing (ZF) and minimum mean square error (MMSE) receiver processing with/without perfect channel state information (CSI) at the base station (BS). This is achieved by exploiting the statistical properties of the intrinsic interference that is characteristic of FBMC systems. Analytical results are also developed for power scaling in the uplink of MU massive MIMO-FBMC systems. The above analysis of the achievable sum-rates and corresponding power scaling laws is subsequently extended to multi-cell scenarios considering both perfect as well as imperfect CSI, and the effect of pilot contamination. The delay-spread-induced performance erosion imposed on the linear processing aided BS receiver is numerically quantified by simulations. Numerical results are presented to demonstrate the close match between our analysis and simulations, and to illustrate and compare the performance of FBMC and traditional orthogonal frequency division multiplexing (OFDM)-based MU massive MIMO systems. [ABSTRACT FROM AUTHOR]

Due to very low propagation speed of acoustic waves, underwater communication via acoustic waves observe a significant Doppler scaling in the received signal. In addition, due to severe frequency selective fading in underwater acoustic channel, the distinct multi-paths may induce different Doppler scaling factor. In this paper, we investigate a transmission strategy in which we append preamble and post-amble in the data frame to estimate the Doppler scaling factor. The frequency selective fading coefficients and additive noise in the system model are statistically characterized by Nakagami and Generalized Gaussian distribution, respectively. Further, the transmit data is assumed to be orthogonal frequency division multiplexing (OFDM) modulated to mitigate the frequency selective nature of underlying channel. In our analysis, we consider two scenarios: (1) multi-paths have common Doppler scaling factor and (2) multi-paths have different Doppler scaling factor. For both the scenarios, we propose receiver algorithms to detect OFDM symbols corrupted by multi-path propagation. We also discuss the improvement in bit error rate performance by exploiting maximal ratio combining scheme. Finally, we validate our approach in the proposed techniques by showing improvement in bit error rate performance via simulation under various signal to noise ratio and fading conditions. [ABSTRACT FROM AUTHOR]

A one‐dimensional mathematical model has been developed to do the comparative analysis of four design of the desiccant wheel. The mathematical model has been validated with experimental results and shows good agreements with experimental results. In this study, a two‐sector desiccant wheel is modified into a three‐sector wheel by introducing a purge section in the desiccant wheel. Similarly, a four‐sector desiccant wheel is reformed into a six‐sector wheel by installing two purge section in the desiccant wheel and comparative study of these designs have been carried for given ranges of operating conditions. The effect of purge conditions has been also investigated and found that in all operating conditions six‐sector design is a better choice for optimum MRC and ∆T. [ABSTRACT FROM AUTHOR]

Cooperative relaying is an effective technique to combat multi-path fading, improves system capacity and enhances the coverage. In this paper, three different types of operations of infrastructure-based multi-antenna cooperative relay network have been investigated. Closed form expressions of outage probability and average error rate for each type of operation have been derived, when the relay and destination perform maximum ratio combining (MRC) of signals. The effect of antennas installed on relay and its placement has also been studied in this work. [ABSTRACT FROM AUTHOR]

This letter considers channel estimation and uplink achievable rate of the coarsely quantized massive multiple-input multiple-output (MIMO) system with radio frequency (RF) impairments. We utilize an additive quantization noise model and an extended error vector magnitude model to analyze the impacts of low-resolution analog-to-digital converters (ADCs) and RF impairments, respectively. We show that hardware impairments cause a nonzero floor on the channel estimation error, which contraries to the conventional case with ideal hardware. The maximal-ratio combining technique is then used at the receiver, and an approximate tractable expression for the uplink achievable rate is derived. The simulation results illustrate the appreciable compensations between ADCs’ resolution and RF impairments. The proposed studies support the feasibility of equipping economical coarse ADCs and economical imperfect RF components in practical massive MIMO systems. [ABSTRACT FROM AUTHOR]

Multicarrier code division multiple access (MC-CDMA) is a novel wireless communication technology with high spectral efficiency and system performance. However, all multiple access techniques including MC-CDMA were most likely to have multiple access interference (MAI). So, this paper mainly aims at designing a suitable receiver for MC-CDMA system to mitigate such MAI. The classical receivers like maximal-ratio combining and minimum mean square error fail to cancel MAI when the MC-CDMA is subjected to nonlinear distortions, which may occur due to saturated power amplifiers or arbitrary channel conditions. Being highly nonlinear structures, the neural network (NN) receivers such as multilayer perceptron and radial basis function networks could be better alternative for such a case. The possibility NN receiver for a MC-CDMA system under different nonlinear conditions has been studied with respect to both performance and complexity analysis. [ABSTRACT FROM AUTHOR]

In this paper, we consider a radio-frequency identification (RFID) backscatter system with two scenarios: single input multiple output (SIMO) and multiple input single output (MISO). We investigate the impact of channel correlation between the forward and backscatter links on the symbol error rate (SER), and we compare the performance of SIMO and MISO RFID systems with maximum ratio combining reception over arbitrarily correlated Nakagami- $m$ fading channels. In order to gain an insight for the system design, closed-form expressions for the asymptotic SER and an upper bound are derived for $M$ -ary phase-shift keying and quadrature amplitude modulation. The diversity order in the fully correlated cases, revealed from these expressions, is half of that in the partially correlated and uncorrelated cases. Finally, simulations are performed to validate the theoretical analysis. [ABSTRACT FROM AUTHOR]

Ambient backscatter (AmBack) communication, also called “modulation in the air,” has drawn growing interest by both academia and industry recently. In this paper, we investigate and analyze an AmBack system, where the user is equipped with an AmBack circuit at the transmitter and maximum ratio combing at the receiver. By harvesting power from the surrounding radio frequency source, the circuit operation and the signal backscattering can be supported. However, if there is not enough harvested power for the circuit operation, the signal backscattering will be suspended. Different from previous works on AmBack, an adaptive scheme is proposed to opportunistically exploit the residual or full user battery power for insufficient harvested power so that the signal backscattering is always available. However, there is no exact closed-form expression for the outage probability, and its approximation is obtained to facilitate our analysis. For comparison, the traditional non-adaptive scheme is also analyzed, and a closed-form expression for the outage probability is derived. In order to get more insight into both schemes, asymptotic outage performance is also derived when the number of receiver antennas/the noise power is sufficiently large/low. Simulation results demonstrate the tightness and the correctness of the derived outage probabilities, and show that the proposed adaptive scheme can significantly outperform the traditional non-adaptive scheme. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this work is to implement an improved image scrambling algorithm based on length three moduli set to achieve a highly reduced size (size on hard disk) of the encrypted or (moduli) image(s) and a more enhanced secured image. Methodology: This Scheme involves Pixel Scrambling by random number generation and a second layer encryption with Residue Number System (RNS) Forward Conversion with respect to the moduli set {2n -1, 2n, 2n +1} for the encryption stage. The decryption process starts with Reverse Conversion with respect to the moduli set {2n -1, 2n, 2n +1} to decode the pixel and Pixel Unscrambling by the saved sequence from the random number generator. Finding/Results: This scheme achieves an enhanced image encryption process and a more efficient decryption process without loses of any important information of the recovered plain image and about 92% compression ratio of the decrypted image. Also this scheme is efficient in internal memory allocation. It produces cipher images that is at least 2/3 the size of the original image. This saves a minimum 25% of internal memory allocation. Thus a 512 x512 plain image that requires about 262144 bytes of memory results in a 768 x 256 encrypted image requiring just 196608 bytes of memory and saving 65536 of internal memory that would have been allocated. Research Limitation: The scheme is suitable for both colored and grayscale images but it produces a better decrypted image (in terms of picture quality) with grayscale images compared to colored images. Originality/Value: This research work is valuable because it combines random scrambling algorithm with Residue Number System (a not-so-conventional number system that operates a zero carry system) [ABSTRACT FROM AUTHOR]

In this paper, the impact of a multi slot based cooperative spectrum sensing (CSS) on the performance of a cognitive radio (CR) network has been investigated. Each CR user, equipped with an improved energy detector (IED), uses a number of mini slots of the sensing time to perform the spectrum sensing. Each CR uses OR logic to combine the sub local decisions generated in each mini slot to obtain a local decision at CR level. Local decisions are sent to fusion centre (FC) over reporting channel. The FC obtains a final decision about the presence of primary user (PU) by combining the local decisions using a fusion rule: Majority or Maximal Ratio Combining. The performance of the CSS is assessed in terms of detection probability and false alarm probability considering both the sensing and reporting channels are Rayleigh faded. Furthermore, the impact of a number of sensing slots and IED parameter on throughput of CR network is also evaluated under the proposed spectrum sensing scenario. Impacts of several sensing parameters such as sensing channel SNR and reporting channel SNR on the performance of CR network are also evaluated. Performances of two fusion rules under study are compared. Effect of sensing error and synchronisation error is indicated. Further the study is extended for independent but non identically distributed (i.n.i.d.) Rayleigh faded channels as well as for a multiple PU scenario also. [ABSTRACT FROM AUTHOR]

The low-SNR asymptotic capacity of the multiple-input multiple-output (MIMO) optical intensity channel is studied under both average and peak intensity constraints. We focus on low SNR, which can be modeled as the scenario where both constraints proportionally vanish, or where the peak constraint is held constant while the average constraint vanishes. A capacity upper bound is derived and is shown to be tight at low SNR under both scenarios. The capacity achieving input distribution at low SNR is shown to be a maximally correlated vector-binary input distribution. Consequently, the low-SNR capacity of the channel is characterized. As a byproduct, it is shown that for a channel with peak intensity constraints only, or with peak intensity constraints and individual (per aperture) average intensity constraints, a simple scheme composed of coded ON–OFF keying, spatial repetition, and maximum-ratio combining is optimal at low SNR. [ABSTRACT FROM AUTHOR]

In this article, mixture gamma (MG) distribution is used for analysing the performance of L-Hoyt/lognormal composite fading channel. To overcome small-scale fading effect, micro-diversity using maximum ratio combining (MRC) is used at the receiver. Due to mathematical complexity, performance analysis of composite (L-Hoyt/lognormal) fading models is not present in closed form. The analytical expressions for the performance measure are derived in the form of received signal-to-noise ratio (SNR). The impact of system parameters on the energy detector (ED) performance is studied in terms of receiver operating characteristic (ROC) and area under the ROC curve (AUC). Further, the detection threshold parameter is optimised by minimising the total probability of error for L-Hoyt/lognormal channel. The accuracy of the proposed closed-form expressions is validated by comparing all the results with the Monte-Carlo/exact simulations. [ABSTRACT FROM AUTHOR]

Spectrum sensing is the important function of cognitive radio and energy detection is the most popular technique used for spectrum sensing. Detection of the availability of unused spectrum for the secondary user becomes difficult when the channel is affected by composite multipath/shadowed fading. In this paper, the performance analysis of an Energy Detector in Hoyt/gamma composite fading channel with Maximum Ratio Combining employing micro-diversity is analyzed. Analytical expressions for performance parameters, i.e., the average probability of detection and the average area under the receiver operating characteristics curve are evaluate. The effect of diversity on the performance of energy detector is also studied. Monte-Carlo simulation results have verified the accuracy of the proposed analysis. [ABSTRACT FROM AUTHOR]

Supertree methods enable the reconstruction of large phylogenies. The supertree problem can be formalized in different ways in order to cope with contradictory information in the input. Some supertree methods are based on encoding the input trees in a matrix; other methods try to find minimum cuts in some graph. Recently, we introduced Bad Clade Deletion (BCD) supertrees which combines the graph-based computation of minimum cuts with optimizing a global objective function on the matrix representation of the input trees. The BCD supertree method has guaranteed polynomial running time and is very swift in practice. The quality of reconstructed supertrees was superior to matrix representation with parsimony (MRP) and usually on par with SuperFine for simulated data; but particularly for biological data, quality of BCD supertrees could not keep up with SuperFine supertrees. Here, we present a beam search extension for the BCD algorithm that keeps alive a constant number of partial solutions in each top-down iteration phase. The guaranteed worst-case running time of the new algorithm is still polynomial in the size of the input. We present an exact and a randomized subroutine to generate suboptimal partial solutions. Both beam search approaches consistently improve supertree quality on all evaluated datasets when keeping 25 suboptimal solutions alive. Supertree quality of the BCD Beam Search algorithm is on par with MRP and SuperFine even for biological data. This is the best performance of a polynomial-time supertree algorithm reported so far. [ABSTRACT FROM AUTHOR]

This paper presents some results on single error detection and correction based on the Redundant Residue Number System (RRNS).The proposed technique utilizes the Mixed Radix Conversion (MRC) and the Modulus Projection (MP) algorithms that significantly simplifies the error correction process for integers. The MP considerably reduces the computational steps and hardware architecture and further improve the processing speed. This results in a considerable improvement in the speed by 97% and tends to require about 96% less hardware resources in the proposed scheme when compared with the existing scheme used in this work. The proposed scheme is built on simple adders in the design of the architecture which saw a considerable improvement in both area and speed in as compared to the work by Yangyanget. al [6] which used ROMs and latches for the design of their architecture. [ABSTRACT FROM AUTHOR]

In most wireless communication systems, the additive noise is assumed to be Gaussian. However, there are many practical applications where non-Gaussian noise impairs the received signal. Examples include co-channel and adjacent channel interference in mobile cellular systems, impulsive noise in wireless and power-line communications, ultra-wide-band interference and multi-user interference in wireless systems, and spectrum sensing. To cover this issue, we consider in this paper the application of the sum of generalized Gaussian (GG) random variables (RVs). To this end, we consider single-input multiple-output (SIMO) systems that operate over Nakagami-m fading channels in the presence of an additive white generalized Gaussian noise (AWGGN). Specifically, we derive a closed-form expression for the bit error rate (BER) of several coherent digital modulation schemes using maximal ratio combining diversity in the Nakagami-m fading channels subject to an AWGGN. The derived expression is obtained based on the fact that the sum of L GG RVs can be approximated by a single GG RV with a suitable shaping parameter. In addition, the obtained BER expression is valid for integer and non-integer value of the fading parameter m. Analytical results are supported by Monte-Carlo simulations to validate the analysis. [ABSTRACT FROM AUTHOR]

Increasing number of antennas are closely packed in emerging multiantenna systems and correlation among them can no longer be ignored. In this paper, such a multiantenna spectrum sensing system is investigated considering dual, triple, four and up to infinite number of correlated antenna branches. Constant, arbitrary and exponential correlation among the antenna branches are considered. Closed form expressions for the detection probability, in terms of the confluent hypergeometric function, is derived assuming maximal ratio combining (MRC) and equal gain combining (EGC) diversity techniques in Nakagami-$m$ multipath fading channel. Numerical results quantify the interbranch correlation that impacts the detector performance significantly. However, results also show that this effect could be compensated by employing the appropriate diversity combining technique and by increasing the diversity branches. Furthermore, we find that at high $m$ values (Rician like channel), low false alarm probability and highly correlated environments, EGC which is a simpler scheme performs as good as MRC which is a more complex scheme. [ABSTRACT FROM AUTHOR]