bluuebunny/crossref_metadata_2025 huggingface dataset:
Beneficial effects of colchicine for moderate to severe COVID-19: a randomised, double-blinded, placebo-controlled clinical trial
Authors: Lopes Maria Isabel , Bonjorno Leticia P , Giannini Marcela C , Amaral Natalia B , Menezes Pamella Indira , Dib Saulo Musse , Gigante Samara Libich , Benatti Maira N , Rezek Uebe C , Emrich-Filho Laerte L , Sousa Betania A A , Almeida Sergio C L , Luppino Assad Rodrigo , Veras Flavio P , Schneider Ayda , Rodrigues Tamara S , Leiria Luiz O S , Cunha Larissa D , Alves-Filho Jose C , Cunha Thiago M , Arruda Eurico , Miranda Carlos H , Pazin-Filho Antonio , Auxiliadora-Martins Maria , Borges Marcos C , Fonseca Benedito A L , Bollela Valdes R , Del-Ben Cristina M , Cunha Fernando Q , Zamboni Dario S , Santana Rodrigo C , Vilar Fernando C , Louzada-Junior Paulo , Oliveira Rene D R
Published: February 2021

Objective

To evaluate whether the addition of colchicine to standard treatment for COVID-19 results in better outcomes.

Design

We present the results of a randomised, double-blinded, placebo-controlled clinical trial of colchicine for the treatment of moderate to severe COVID-19, with 75 patients allocated 1:1 from 11 April to 30 August 2020. Colchicine regimen was 0.5 mg thrice daily for 5 days, then 0.5 mg twice daily for 5 days. The primary endpoints were the need for supplemental oxygen, time of hospitalisation, need for admission and length of stay in intensive care unit and death rate.

Results

Seventy-two patients (36 for placebo and 36 for colchicine) completed the study. Median (and IQR) time of need for supplemental oxygen was 4.0 (2.0–6.0) days for the colchicine group and 6.5 (4.0–9.0) days for the placebo group (p<0.001). Median (IQR) time of hospitalisation was 7.0 (5.0–9.0) days for the colchicine group and 9.0 (7.0–12.0) days for the placebo group (p=0.003). At day 2, 67% versus 86% of patients maintained the need for supplemental oxygen, while at day 7, the values were 9% versus 42%, in the colchicine and the placebo groups, respectively (log rank; p=0.001). Two patients died, both in placebo group. Diarrhoea was more frequent in the colchicine group (p=0.26).

Conclusion

Colchicine reduced the length of both, supplemental oxygen therapy and hospitalisation. The drug was safe and well tolerated. Once death was an uncommon event, it is not possible to ensure that colchicine reduced mortality of COVID-19.

Trial registration number

RBR-8jyhxh.
Using molecular testing and whole-genome sequencing for tuberculosis diagnosis in a low-burden setting: a cost-effectiveness analysis using transmission-dynamic modelling
Authors: Mugwagwa Tendai , Abubakar Ibrahim , White Peter J
Published: February 2021

Background

Despite progress in TB control in low-burden countries like England and Wales, there are still diagnostic delays. Molecular testing and/or whole-genome sequencing (WGS) provide more rapid diagnosis but their cost-effectiveness is relatively unexplored in low-burden settings.

Methods

An integrated transmission-dynamic health economic model is used to assess the cost-effectiveness of using WGS to replace culture-based drug-sensitivity testing, versus using molecular testing versus combined use of WGS and molecular testing, for routine TB diagnosis. The model accounts for the effects of faster appropriate treatment in reducing transmission, benefiting health and reducing future treatment costs. Cost-effectiveness is assessed using incremental net benefit (INB) over a 10-year horizon with a quality-adjusted life-year valued at £20 000, and discounting at 3.5% per year.

Results

WGS shortens the time to drug sensitivity testing and treatment modification where necessary, reducing treatment and hospitalisation costs, with an INB of £7.1 million. Molecular testing shortens the time to TB diagnosis and treatment. Initially, this causes an increase in annual costs of treatment, but averting transmissions and future active TB disease subsequently, resulting in cost savings and health benefits to achieve an INB of £8.6 million (GeneXpert MTB/RIF) or £11.1 million (Xpert-Ultra). Combined use of Xpert-Ultra and WGS is the optimal strategy we consider, with an INB of £16.5 million.

Conclusion

Routine use of WGS or molecular testing is cost-effective in a low-burden setting, and combined use is the most cost-effective option. Adoption of these technologies can help low-burden countries meet the WHO End TB Strategy milestones, particularly the UK, which still has relatively high TB rates.
Saving Lives: Recognizing and Intervening with Youth at Risk for Suicide
Authors: Arango Alejandra , Gipson Polly Y. , Votta Jennifer G. , King Cheryl A.
Published: February 2021

Suicide is the second leading cause of death for youth in the United States. Fortunately, substantial advances have been achieved in identifying and intervening with youth at risk. In this review, we first focus on advances in proactive suicide risk screening and psychoeducation aimed at improving the recognition of suicide risk. These strategies have the potential to improve our ability to recognize and triage youth at risk who may otherwise be missed. We then review recent research on interventions for youth at risk. We consider a broad range of psychotherapeutic interventions, including crisis interventions in emergency care settings. Though empirical support remains limited for interventions targeting suicide risk in youth, effective and promising approaches continue to be identified. We highlight evidence-based screening and intervention approaches as well as challenges in these areas and recommendations for further investigation.
Does Mycobacterium tuberculosis var. bovis Survival in the Environment Confound Bovine Tuberculosis Control and Eradication? A Literature Review
Authors: Allen Adrian R. , Ford Tom , Skuce Robin A.
Published: February 2021

Bovine tuberculosis (bTB) is one of the globe’s most common, multihost zoonoses and results in substantial socioeconomic costs for governments, farming industries, and tax payers. Despite decades of surveillance and research, surprisingly, little is known about the exact mechanisms of transmission. In particular, as a facultative intracellular pathogen, to what extent does survival of the causative agent, Mycobacterium tuberculosis var. bovis (M. bovis), in the environment constitute an epidemiological risk for livestock and wildlife? Due largely to the classical pathology of cattle cases, the received wisdom was that bTB was spread by direct inhalation and exchange of bioaerosols containing droplets laden with bacteria. Other members of the Mycobacterium tuberculosis complex (MTBC) exhibit differing host ranges, an apparent capacity to persist in environmental fomites, and they favour a range of different transmission routes. It is possible, therefore, that infection from environmental sources of M. bovis could be a disease transmission risk. Recent evidence from GPS-collared cattle and badgers in Britain and Ireland suggests that direct transmission by infectious droplets or aerosols may not be the main mechanism for interspecies transmission, raising the possibility of indirect transmission involving a contaminated, shared environment. The possibility that classical pulmonary TB can be simulated and recapitulated in laboratory animal models by ingestion of contaminated feed is a further intriguing indication of potential environmental risk. Livestock and wildlife are known to shed M. bovis onto pasture, soil, feedstuffs, water, and other fomites; field and laboratory studies have indicated that persistence is possible, but variable, under differing environmental conditions. Given the potential infection risk, it is timely to review the available evidence, experimental approaches, and methodologies that could be deployed to address this potential blind spot and control point. Although we focus on evidence from Western Europe, the concepts are widely applicable to other multihost bTB episystems.
Hypervolemic Hyponatremia as a Reversible Cause of Cardiopulmonary Arrest in a Postpartum Patient with Preeclampsia
Authors: Hsu Richard , Tong Anna , Hsu Chaur-Dong
Published: February 2021

Although the incidence of preeclampsia complicated by hyponatremia is reportedly rare, the effects on the maternal outcome are severe and life-threatening. Here, we describe a case of a patient with preeclampsia who coded postpartum and was discovered to have hypervolemic hyponatremia and subsequently recovered after fluid diuresis and resolution of hyponatremia. While hyponatremia in preeclampsia is rare, it is even more unique for it to lead to cardiopulmonary arrest consequently. Therefore, sodium levels and fluid status should be monitored closely and promptly corrected without delay to prevent cardiopulmonary arrest in patients with preeclampsia.
Desafío de la Política Fiscal y Monetaria
Authors: García Carlos
Published: February 2021

Hace unos días un estimado amigo me mandó un meme sobre economistas: mostraba a un hombre tirado en la playa junto a su esposa. Ella le pregunta si él está disfrutando de las vacaciones, lo que el economista responde airadamente que no es posible relajarse porque la inflación podría estar acechando en algún lugar del mundo. Continuar leyendo...
Effect of Bronchoscopic Lung Volume Reduction in Advanced Emphysema on Energy Balance Regulation
Authors: Sanders Karin , Klooster Karin , Vanfleteren Lowie E.G.W. , Plasqui Guy , Dingemans Anne-Marie , Slebos Dirk-Jan , Schols Annemie M.W.J.
Published: February 2021

Background: Hypermetabolism and muscle wasting frequently occur in patients with severe emphysema. Improving respiratory mechanics by bronchoscopic lung volume reduction (BLVR) might contribute to muscle maintenance by decreasing energy requirements and alleviating eating-related dyspnoea. Objective: The goal was to assess the impact of BLVR on energy balance regulation. Design: Twenty emphysematous subjects participated in a controlled clinical experiment before and 6 months after BLVR. Energy requirements were assessed: basal metabolic rate (BMR) by ventilated hood, total daily energy expenditure (TDEE) by doubly labelled water, whole body fat-free mass (FFM) by deuterium dilution, and physical activity by accelerometry. Oxygen saturation, breathing rate, and heart rate were monitored before, during, and after a standardized meal via pulse oximetry and dyspnoea was rated. Results: Sixteen patients completed follow-up, and among those, 10 patients exceeded the minimal clinically important difference of residual volume (RV) reduction. RV was reduced with median (range) 1,285 mL (−2,430, −540). Before BLVR, 90% of patients was FFM-depleted despite a normal BMI (24.3 ± 4.3 kg/m2). BMR was elevated by 130%. TDEE/BMR was 1.4 ± 0.2 despite a very low median (range) daily step count of 2,188 (739, 7,110). Following BLVR, the components of energy metabolism did not change significantly after intervention compared to before intervention, but BLVR treatment decreased meal-related dyspnoea (4.1 vs. 1.7, p = 0.019). Conclusions: Impaired respiratory mechanics in hyperinflated emphysematous patients did not explain hypermetabolism. Clinical Trial Registry Number: NCT02500004 at www.clinicaltrial.gov.
Canonical Pathways Associated with Blood Pressure Response to Sleep Apnea Treatment: A Post Hoc Analysis
Authors: Zapater Andrea , Santamaria-Martos Fernando , Targa Adriano , Pinilla Lucía , Sánchez-de-la-Torre Alicia , Benítez Iván David , Martínez-García Miguel Ángel , Barbé Ferran , Sánchez-de-la-Torre Manuel
Published: February 2021

Background: Several studies have reported an association between microRNAs (miRNAs) and hypertension or cardiovascular disease (CVD). In a previous study performed on a group of 38 patients, we observed a cluster of 3 miRNAs (miR-378a-3p, miR-100-5p, and miR-486-5p) that were functionally associated with the cardiovascular system that predicted a favorable blood pressure (BP) response to continuous positive airway pressure (CPAP) treatment in patients with resistant hypertension (RH) and obstructive sleep apnea (OSA) (HIPARCO score). However, little is known regarding the molecular mechanisms underlying this phenomenon. Objectives: The aim of the study was to perform a post hoc analysis to investigate the genes, functions, and pathways related to the previously found HIPARCO score miRNAs. Methods: We performed an enrichment analysis using Ingenuity pathway analysis. The genes potentially associated with the miRNAs were filtered based on their confidence level. Particularly for CVD, only the genes regulated by at least 2 of the miRNAs were studied. Results: We observed that the miRNAs studied regulate 200–249 molecules associated with several functions and diseases, including extracranial solid tumors and abdominal neoplasms, among others. The cardiac hypertrophy and NF-kB signaling pathways were identified as the cardiovascular pathways most influenced by these 3 miRNAs. Conclusions: The mechanisms by which CPAP treatment decreases the BP in OSA patients with RH could be related to the cardiac hypertrophy and NF-kB signaling pathways. Further investigations will be necessary to confirm these findings, contributing to the elucidation of new therapeutic targets in patients who do not respond to CPAP treatment.
High Accuracy of Digital Tomosynthesis-Guided Bronchoscopic Biopsy Confirmed by Intraprocedural Computed Tomography
Authors: Katsis James , Roller Lance , Lester Michael , Johnson Joyce , Lentz Robert , Rickman Otis , Maldonado Fabien
Published: February 2021

Background: Digital fluoroscopic tomosynthesis-guided electromagnetic navigational bronchoscopy (F-ENB) is a novel adjunct to ENB associated with higher diagnostic yield. The likelihood of F-ENB allowing accurate placement of a biopsy needle within a target remains unclear. Objective: This study intends to determine the accuracy of F-ENB as confirmed by cone-beam computed tomography (CBCT) scan. Methods: Patients undergoing CBCT-assisted ENB for lung nodule biopsy were prospectively enrolled. ENB was performed followed by digital tomosynthesis correction. Once optimal F-ENB alignment was achieved, and a needle was advanced into the expected location of the nodule followed by CBCT. The primary outcome was the percentage of “needle-in-lesion” hits, defined as needle tip within the nodule in 3 planes. Secondary outcomes were diagnostic yield, procedure and room time, complications, radiation, and distance between the needle tip and nodule. Results: Twenty-six patients with a total of 29 nodules were enrolled. Mean nodule size was 13 mm (±4 mm) in maximal axial dimension, 83% (n = 24) were located in the peripheral third of the chest, and 17% (n = 5) had a bronchus sign. F-ENB guidance resulted in needle-in-lesion in 21 of 29 nodules (72%). Mean needle tip-to-nodule distance for nonhits was 1.75 mm (±1.35 mm). There were no complications. Conclusion: F-ENB resulted in a needle-in-lesion biopsy in greater than 70% of nodules despite features traditionally associated with poor diagnostic yield (size, absence of bronchus sign). Mean distance between needle tip and target for nonhits was less than 2 mm. These data suggest F-ENB alignment is accurate for small peripheral nodules.
Air Trapping Is Associated with Heterozygosity for Alpha-1 Antitrypsin Mutations in Patients with Asthma
Authors: Aiello Marina , Ghirardini Marianna , Marchi Laura , Frizzelli Annalisa , Pisi Roberta , Ferrarotti Ilaria , Bertorelli Giuseppina , Chetta Alfredo
Published: February 2021

Background: Alpha-1 antitrypsin deficiency (AATD) is a hereditary disorder involving lungs, characterized by low serum concentration of the protein alpha-1 antitrypsin (AAT) also called proteinase inhibitor (PI). Asthma is common in AATD patients, but there are only few data on respiratory function in asthmatic patients with AATD. Objectives: The aim of the study was to evaluate lung function in asthmatic outpatients with mutation in the SERPINA1 gene coding for AAT versus asthmatic subjects without mutation. Methods: We performed the quantitative analysis of the serum concentration of AAT in 600 outpatients affected by mild to moderate asthma from the University Hospital of Parma, Italy. Fifty-seven of them underwent the genetic analysis subsequently; they were subdivided into mutated and non-mutated subjects. All the mutated patients had a heterozygous genotype, except 1 (PI*SS). We assessed the lung function through a flow-sensing spirometer and the small airway parameters through an impulse oscillometry system. Results: The values of forced vital capacity (% predicted) and those of the residual volume to total lung capacity ratio (%) were, respectively, lower and higher in patients mutated versus patients without mutation, showing a significantly greater air trapping (p = 0.014 and p = 0.017, respectively). Moreover, patients with mutation in comparison to patients without mutation showed lower forced expiratory volume in 3 s (% predicted) and forced expiratory volume in 6 s (L) spirometric values, reflecting a smaller airways contribution. Conclusions: In asthmatic patients, heterozygosity for AAT with PI*MZ and PI*MS genotypes was associated with small airway dysfunction and with lung air trapping.
Prognostic Value of Oxygenated Hemoglobin Assessed during Acute Exacerbations of Chronic Pulmonary Disease
Authors: Hinke Clemens F. , Jörres Rudolf A. , Alter Peter , Bals Robert , Bornitz Florian , Kreuter Michael , Herth Felix J.F. , Kahnert Kathrin , Kellerer Christina , Watz Henrik , Budweiser Stephan , Trudzinski Franziska C.
Published: February 2021

Background: Oxygenated hemoglobin(OxyHem) is a simple-to-measure marker of oxygen content capable of predicting all-cause mortality in stable chronic obstructive pulmonary disease (COPD). Objectives: We aimed to analyze its predictive value during acute exacerbations of COPD (AECOPD). Methods: In this retrospective study, data from 227 patients discharged after severe AECOPD at RoMed Clinical Center Rosenheim, Germany, between January 2012 and March 2018, was analyzed. OxyHem (hemoglobin concentration [Hb] × fractional SpO2, g/dL) was calculated from oxygen saturation measured by pulse oximetry and hemoglobin assessed within 24 h after admission. The follow-up (1.7 ± 1.5 years) covered all-cause mortality, including readmissions for severe AECOPD. Results: During the follow-up period, 127 patients died, 56 due to AECOPD and 71 due to other reasons. Survivors and non-survivors showed differences in age, FVC % predicted, C-reactive protein, hemoglobin, Cr, Charlson Comorbidity Index (CCI), and OxyHem (p < 0.05 each). Significant independent predictors of survival were BMI, Cr or CCI, FEV1 % predicted or FVC % predicted, Hb, or OxyHem. The predictive value of OxyHem (p = 0.006) was superior to that of Hb or SpO2 and independent of oxygen supply during blood gas analysis. OxyHem was also predictive when using a cutoff value of 12.1 g/dL identified via receiver operating characteristic curves in analyses including either the CCI (hazard ratio 1.85; 95% CI 1.20, 2.84; p = 0.005) or Cr (2.04; 95% CI 1.35, 3.10; p = 0.001) as covariates. Conclusion: The concentration of OxyHem provides independent, easy-to-assess information on long-term mortality risk in COPD, even if measured during acute exacerbations. It therefore seems worth to be considered for broader clinical use.
Interconnection viability of high demand isolated area through a HVDC-VSC link
Authors: Varela Juan A. , Rios Mario A.
Published: February 2021

Electrically isolated areas are separated by a great distance and, normally, have a considerably low demand; in consequence, these are non-interconnected from the main power grid or electrical national transmission systems. Great distance and low demand are the reasons why an interconnection project in high voltage AC is not feasible in most of these cases. Nevertheless, there are some isolated areas with high power demand and even though they are separated from the main grid by large distances and hard terrains; however, it is still reasonable to think about an interconnection project. This paper had developed a methodology that allows the evaluation of viability, technically and economically, of a HDVC-VSC interconnection project for great distance and high demand considering overhead and/or underground DC line. The methodology was applied to a case of study in Peru, based on the projected interconnection between Moyobamba and the isolated area of Iquitos; showing that HVDC is a feasible alternative.
Application of AHP algorithm on power distribution of load shedding in island microgrid
Authors: Nguyen An T. , Le Nghia T. , Quyen Anh. H. , T. Phan Binh T. , Trieu Tan P. , Hua Thien D.
Published: February 2021

This paper proposes a method of load shedding in a microgrid system operated in an Island Mode, which is disconnected with the main power grid and balanced loss of the electrical power. This proposed method calculates the minimum value of the shed power with reference to renewable energy sources such as wind power generator, solar energy and the ability to control the frequency of the generator to restore the frequency to the allowable range and reduce the amount of load that needs to be shed. Computing the load importance factor (LIF) using AHP algorithm supports to determine the order of which load to be shed. The damaged outcome of load shedding, thus, will be noticeably reduced. The experimental results of this proposed method is demonstrated by simulating on IEEE 16-Bus microgrid system with six power sources.
A 5G mm-wave compact voltage-controlled oscillator in 0.25 µm pHEMT technology
Authors: Es-saqy Abdelhafid , Abata Maryam , Mehdi Mahmoud , Fattah Mohammed , Mazer Said , El Bekkali Moulhime , Algani Catherine
Published: February 2021

A 5G mm-wave monolithic microwave integrated circuit (MMIC) voltage-controlled oscillator (VCO) is presented in this paper. It is designed on GaAs substrate and with 0.25 µm-pHEMT technology from UMS foundry and it is based on pHEMT varactors in order to achieve a very small chip size. A 0dBm-output power over the entire tuning range from 27.67 GHz to 28.91 GHz, a phase noise of -96.274 dBc/Hz and -116.24 dBc/Hz at 1 and 10 MHz offset frequency from the carrier respectively are obtained on simulation. A power consumption of 111 mW is obtained for a chip size of 0.268 mm2. According to our knowledge, this circuit occupies the smallest surface area compared to pHEMTs oscillators published in the literature.
Elevator controller based on implementing a random access memory in FPGA
Authors: Saeed Azzad Bader
Published: February 2021

Previous techniques of elevator controllers suffer from two main challenges: processing time, and software size. In this work these challenges have been overcame by implementing a controller random access memory (RAM) in a fast FPGA for a proto-type of two-floors elevator, as known the RAM and FPGA are fast devices. A look-up-table LUT (which is fast technique) has been proposed for this work, this LUT has represented a proposed relation between 10 and 7 lines, the states of the sensors and switches have been represented by the 10 input lines, and the commands for the motors of slide door and traction machine have been represented by the 7 output lines. The proposed LUT has been schematically realize by a (10×7) bits RAM which has been implemented in field programmable gate arrays (FPGA). The proposed system has been performed using 'ISE Design Suit' software package and FPGA Spartan6 SP-605 evaluation kit, the clock frequency of this FPGA is 200 MHz which is respectively high. The processing time and software size of the proposed controller had reached to 20ns and 3.75 MB, which they are less than that obtained from the results of previous techniques.
Design and performance analysis of PV grid-tied system with energy storage system
Authors: Kumar Jerry , Parhyar Nanik Ram , Panjwani Manoj Kumar , Khan Danish
Published: February 2021

With the increasing demand for solar energy as a renewable source has brought up new challenges in the field of energy. However, one of the main advantages of photovoltaic (PV) power generation technology is that it can be directly connected to the grid power generation system and meet the demand of increasing energy consumption. Large-scale PV grid-connected power generation system put forward new challenges on the stability and control of the power grid and the grid-tied photovoltaic system with an energy storage system. To overcome these problems, the PV grid-tied system consisted of 8 kW PV array with energy storage system is designed, and in this system, the battery components can be coupled with the power grid by AC or DC mode. In addition, the feasibility and flexibility of the maximum power point tracking (MPPT) charge controller are verified through the dynamic model built in the residential solar PV system. Through the feasibility verification of the model control mode and the strategy control, the grid-connected PV system combined with reserve battery storage can effectively improve the stability of the system and reduce the cost of power generation. To analyze the performance of the grid-tied system, some real-time simulations are performed with the help of the system advisor model (SAM) that ensures the satisfactory working of the designed PV grid-tied System.
The design of an efficient class E-LCCL capacitive power transfer system through frequency tuning method
Authors: Hasan Khairul Kamarudin , Saat Shakir , Yusop Yusmarnita , Husin Huzaimah , Md Sin Nor Diyana
Published: February 2021

In this work, the optimum zero voltage switching (ZVS) of Class E-LCCL capacitive power transfer (CPT) was determined via frequency tuning method. Through this an efficient system can be guanranteed although there is a change in the capacitive plates distance. This study used a Class-E LCCL inverter, as it can operate at a high alternate current frequency, besides producing low switching losses and minimal power losses. Specifically, this study conducted simulations and experiments to analyse the performance of an LCCL CPT System at 1 MHz operating frequency and 24 V DC supply voltage. Using an air gap distance of 0.1 cm, the designed CPT system prototype successfully achieved an output power of 10W and an efficiency of 95.45%. This study also found that by tuning the resonant frequency of the Class E-LCCL system, the optimum ZVS can be obtained although capacitive plate distance was varied from 1-3 cm via experimental. The results of this study could benefit medical implant and portable device development, consumer electronics, and environments that involve electrical hazards.
DC-DC converter with 50 kHz-500 kHz range of switching frequency for passive component volume reduction
Authors: Kasiran Mohd Amirul Naim , Ponniran Asmarashid , Siam Nurul Nabilah Mad , Yatim Mohd Hafizie , Che Ibrahim Nor Azmira , Md Yunos Asmawi
Published: February 2021

This paper presents the relationship of switching frequency towards passive components volume of DC-DC boost converter. Principally, the inductor current ripple and capacitor voltage ripple must be considered in order to design the inductor and capacitor, respectively. By increasing the switching frequency, smaller size and volume of passive component can be designed. As the consequences, the switching loss increases during switching transition at turn-ON and turn-OFF conditions. This paper used soft-switching technique to reduce the switching loss at turn-ON condition. The soft-switching technique is realized by adding resonant circuit in DC-DC boost converter. The effectiveness of resonant circuit will be analysed, thus, the efficiency of the converter can be improved. The range of switching frequency considered in the experimental are 50 kHz to 500 kHz. A 100 W prototype has been developed and tested in order to verify the principle. The switching loss experimentally confirm reduced by implementing soft-switching technique with efficiency converter improved from 96.36% to 97.12% when 500 kHz of switching frequency is considered. The passive components volume reduction is achieved when high switching frequency is used where the total volume of passive component when 50 kHz and 500 kHz are 0.083 dm3 and 0.010 dm3, respectively.
A novel fuzzy based controller to reduce circulating currents in parallel interleaved converter connected to the grid
Authors: Gaddameedhi Sravanthy , Srinivas P.
Published: February 2021

This paper exhibits suppression strategy of low frequency circulating current components for parallel inter-leaved converters. Here inverters are parallelized by magnetically coupled inductors. Traditionally, carrier interleaved technique was used to get lower distorted output voltage, but it gives a higher circulating currents to flow through the Two-VSC‘s. The mutual inductance of the coupled inductors (CI) is utilized for minimizing circulating currents of high frequency components. Nevertheless, CI can‘t have capability to riddle the components generated by low frequency. When these circulating currents extremely increases may leads to CI saturation, elevated switching losses and diminishes the entire performance of system. Here author identified a novel control technique for a grid-connected parallel inter-leaved converter depending on approach of energy shaping control (ECS). This controller diminishes the value of the low frequency components of circulating current (LFCC). The performance of the proposed circuit is evaluated in simulation mode and correlated with the conventional proportional integral control (PIC) and the linear quadratic control (LQC). The Fuzzy controller is also included in this work to enhance the converter performance effectively and to diminish the circulating currents along with the healthy harmonic performance analysis.
Speed controller design for three-phase induction motor based on dynamic adjustment grasshopper optimization algorithm
Authors: Algamluoli Ammar Falah , Abbas Nizar Hadi
Published: February 2021

Three-phase induction motor (TIM) is widely used in industrial application like paper mills, water treatment and sewage plants in the urban area. In these applications, the speed of TIM is very important that should be not varying with applied load torque. In this study, direct on line (DOL) motor starting without controller is modelled to evaluate the motor response when connected directly to main supply. Conventional PI controller for stator direct current and stator quadrature current of induction motor are designed as an inner loop controller as well as a second conventional PI controller is designed in the outer loop for controlling the TIM speed. Proposed combined PI-lead (CPIL) controllers for inner and outer loops are designed to improve the overall performance of the TIM as compared with the conventional controller. In this paper, dynamic adjustment grasshopper optimization algorithm (DAGOA) is proposed for tuning the proposed controller of the system. Numerical results based on well-selected test function demonstrate that DAGOA has a better performance in terms of speed of convergence, solution accuracy and reliability than SGOA. The study results revealed that the currents and speed of TIM system using CPIL-DAGOA are faster than system using conventional PI and CPIL controllers tuned by SGOA. Moreover, the speed controller of TIM system with CPIL controlling scheme based on DAGOA reached the steady state faster than others when applied load torque.
Ultra-wide band energy harvesting for ultra-low power electronics applications
Authors: Rashid Nasr , Shehata Mohamed
Published: February 2021

In this work, the feasibility of energy harvesting in the useful UWB band (i.e., 3.1-10.6 GHz) is analytically investigated. A typical UWB communications/EH chain in this band is modeled and analyzed, considering the spectral constraints imposed by the federal communications commission (FCC) to UWB signaling. Based on the developed model, accurate analytical expressions are derived for the average received powers of two common types of impulse radio UWB (IR-UWB) signaling waveforms. Numerical simulations on the system-level show excellent agreement with the obtained analytical expressions. Moreover, the DC power levels expected from spectrally constrained IR-UWB waveforms are extremely low (less than 0.3 microwatt) and, accordingly, provide useful guidelines for the design and development of ULP electronics applications in the sub-microwatt range.
Estimation of posture and prediction of the elderly getting out of bed using a body pressure sensor
Authors: Hagihara Atsushi , Harada Fumiko , Shimakawa Hiromitsu
Published: February 2021

We propose an IoT support system for estimating the posture of the care recipient on the bed from the body pressure of the care recipient measured by a sheet-type body pressure sensor, and detecting the posture related to leaving the bed in real time. In addition, we propose a method that predicts getting out of the bed before the care recipient takes a posture related to getting out of the bed by considering the state transition. Intervention experiment showed that using body pressure features as an explanatory variable and applying machine learning, 16 types of postures on the bed of care recipients with an F value of 0.7 or more could be identified. From the experiment without intervention, by applying the hidden Markov model, we calculated the transition probability to each hidden state when the care recipient getting out of the bed and the transition probability to each hidden state when the care recipient not getting out of the bed. As a result, there was a difference of about 0.1 in the transition probability of the state related to raising upper body.
Constrained discrete model predictive control of a greenhouse system temperature
Authors: Hamidane Hafsa , El Faiz Samira , Guerbaoui Mohammed , Ed-Dahhak Abdelali , Lachhab Abdeslam , Bouchikhi Benachir
Published: February 2021

In this paper, a constrained discete model predictive control (CDMPC) strategy for a greenhouse inside temperature is presented. To describe the dynamics of our system’s inside temperature, an experimental greenhouse prototype is engaged. For the mathematical modeling, a state space form which fits properly the acquired data of the greenhouse temperature dynamics is identified using the subspace system identification (N4sid) algorithm. The obtained model is used in order to develop the CDMPC starategy which role is to select the best control moves based on an optimization procedure under the constraints on the control notion. For efficient evaluation of the proposed control approach Matlab/Simulink and Yalmip optimization toolbox are used for algorithm and blocks implementation. The simulation results confirm the accuracy of the controller that garantees both the control and the reference tracking objectives.
ECG signal denoising using a novel approach of adaptive filters for real-time processing
Authors: Al-Safi Amean
Published: February 2021

Electrocardiogram (ECG) is considered as the main signal that can be used to diagnose different kinds of diseases related to human heart. During the recording process, it is usually contaminated with different kinds of noise which includes power-line interference, baseline wandering and muscle contraction. In order to clean the ECG signal, several noise removal techniques have been used such as adaptive filters, empirical mode decomposition, Hilbert-Huang transform, wavelet-based algorithm, discrete wavelet transforms, modulus maxima of wavelet transform, patch based method, and many more. Unfortunately, all the presented methods cannot be used for online processing since it takes long time to clean the ECG signal. The current research presents a unique method for ECG denoising using a novel approach of adaptive filters. The suggested method was tested by using a simulated signal using MATLAB software under different scenarios. Instead of using a reference signal for ECG signal denoising, the presented model uses a unite delay and the primary ECG signal itself. Least mean square (LMS), normalized least mean square (NLMS), and Leaky LMS were used as adaptation algorithms in this paper.
New design of wideband microstrip branch line coupler using T-shape and open stub for 5G application
Authors: Abdulbari Ali Abdulateef , Abdul Rahim Sharul Kamal , Abidin Abd Aziz Mohamad Zoinol , Tan K. G. , Noordin N. K. , Nor M. Z. M.
Published: February 2021

A new design of wideband branch-line coupler (BLC) using T-shape with open stub microstrip line is proposed. The branch line coupler is integrated with low and high impedance λ/4 transmission lines to achieve the comparatively compact size of (27.2 mm × 16.5 mm). operating the bandwidth in simulated of BLC from 2.9 to 4 GHz is obtained 30.22% with a frequency center of 3.5 GHz. Meanwhile, the measured bandwidth of the BLC is cover from 2.8 GHz to 4.22 GHz is equal 33.40% at the center frequency 3.55 GHz respectively. The BLC simulated has low isolation and high return loss of -29.28 dB and -30.69 dB at the center frequency 3.5 GHz.Whereas, the measured result has a simple difference in the return loss and isolation are -27.43dB and -24.46 dB at the frequency 3.55GHz respectively. This BLC design has a good coupling factor of -2.97 and insertion loss of -3.65 dB. Furthermore, it obtains an excellent amplitude and phases different between two output of ±0.1 and 93.6°±3.4° with high performance. There is a good agreement between the simulated result and the measured result. This branch line coupler design used for 5G applications for future wireless communication systems.
Cloud radio access network fronthaul solution using optimized dynamic bandwidth allocation algorithm
Authors: Awasume Ebude Carine , Musyoki Stephen , Oduol Vitalice Kalecha
Published: February 2021

In order to address the challenges that have come with the exploding demand for higher speed, traffic growth and mobile wireless devices, Mobile network operators have decided to move to the notion of small cells based on cloud radio access network. The merits of cloud based RAN includes the ease of infrastructure deployment and network management as well as the fact that its performance are optimized and it is cost effective the merits of cloud based RAN includes the ease of infrastructure deployment and network management as well as the fact that its performance are optimized and it is cost effective. Notwithstanding, cloud radio access network comes with so many strict requirements to be fulfilled for its fronthaul network. In this paper, we have presented these requirements for a 5G fronthaul network. Particular interest on the time division multiplex passive optical network’s challenge of latency was treated by proposing an optimized version of the round robin dynamic bandwidth allocation algorithm. Results obtained show an improvement in the latency of the original algorithm which meets the fronthaul requirement. Other test parameters like jitter and BER were also improved by our proposed optimized algorithm.
Chaos and bifurcation in time delayed third order phase-locked loop
Authors: Harb Bassam , Qudah Mohammad , Ghareeb Ibrahim , Harb Ahmad
Published: February 2021

In this paper, the modern nonlinear theory is applied to a third order phase locked loop (PLL) with a feedback time delay. Due to this delay, different behaviors that are not accounted for in a conventional PLL model are identified, namely, oscillatory instability, periodic doubling and chaos. Firstly, a Pade approximation is used to model the time delay where it is utilized in deriving the state space representation of the PLL under investigation. The PLL under consideration is simulated with and without time delay. It is shown that for certain loop gain (control parameter) and time delay values, the system changes its stability and becomes chaotic. Simulations show that the PLL with time delay becomes chaotic for control parameter value less than the one without time delay, i.e, the stable region becomes narrower. Moreover, the chaotic region becomes wider as time delay increases.
An analytic study of the fractional order model of HIV-1 virus and CD4+ T-cells using adomian method
Authors: Al-Khaled Kamel , Yousef Maha
Published: February 2021

In this article, we study the fractional mathematical model of HIV-1 infection of CD4+ T-cells, by studying a system of fractional differential equations of first order with some initial conditions, we study the changing effect of many parameters. The fractional derivative is described in the caputo sense. The adomian decomposition method (Shortly, ADM) method was used to calculate an approximate solution for the system under study. The nonlinear term is dealt with the help of adomian polynomials. Numerical results are presented with graphical justifications to show the accuracy of the proposed methods.
Web-based material requisition system in the supply chain of construction businesses
Authors: Adedeji Afolabi Olushola , S. Abraham Yewande , Oluwafikunmi Awosika
Published: February 2021

In the construction project delivery process, the supply chain of construction businesses can only be efficient and effective based on the prompt availability of building materials. Whereas, the process of requisition for the materials on the construction site, if not handled appropriately, can adversely affect construction performance. Therefore, the study was aimed at developing a web-based material requisition system (W-BMRS) that will make the supply chain on construction sites seamless and more effective. A use case and an activity block diagram provided an understanding of the users and functionalities of the material requisition platform. In addition, using a different user interface and a database system including a programming language to connect them, the study developed a web-based material requisition system for construction firms using the model view controller (MVC) model. The MVC model comprised of using MySQL, HTML, and PHP. The W-BMRS was tested by sending materials requisition through the supply chain of a construction firm. The results were presented via screenshots of the web-based platform. In conclusion, any construction firm can register on the platform and make use of the web-based materials requisition system to maximize productivity and optimize the use of ICT in their materials’ supply chain process.
Searching surveillance video contents using convolutional neural network
Authors: Mohammad Duaa , Aljarrah Inad , Jarrah Moath
Published: February 2021

Manual video inspection, searching, and analyzing is exhausting and inefficient. This paper presents an intelligent system to search surveillance video contents using deep learning. The proposed system reduced the amount of work that is needed to perform video searching and improved the speed and accuracy. A pre-trained VGG-16 CNNs model is used for dataset training. In addition, key frames of videos were extracted in order to save space, reduce the amount of work, and reduce the execution time. The extracted key frames were processed using the sobel operator edge detector and the max-pooling in order to eliminate redundancy. This increases compaction and avoids similarities between extracted frames. A text file, that contains key frame index, time of occurrence, and the classification of the VGG-16 model, is produced. The text file enables humans to easily search for objects of interest. VIRAT and IVY LAB datasets were used in the experiments. In addition, 128 different classes were identified in the datasets. The classes represent important objects for surveillance systems. However, users can identify other classes and utilize the proposed methodology. Experiments and evaluation showed that the proposed system outperformed existing methods in an order of magnitude. The system achieved the best results in speed while providing a high accuracy in classification.
Design and implementation of DA FIR filter for bio-inspired computing architecture
Authors: Prashanth B. U. V. , Ahmed Mohammed Riyaz , Kounte Manjunath R.
Published: February 2021

This paper elucidates the system construct of DA-FIR filter optimized for design of distributed arithmetic (DA) finite impulse response (FIR) filter and is based on architecture with tightly coupled co-processor based data processing units. With a series of look-up-table (LUT) accesses in order to emulate multiply and accumulate operations the constructed DA based FIR filter is implemented on FPGA. The very high speed integrated circuit hardware description language (VHDL) is used implement the proposed filter and the design is verified using simulation. This paper discusses two optimization algorithms and resulting optimizations are incorporated into LUT layer and architecture extractions. The proposed method offers an optimized design in the form of offers average miminimizations of the number of LUT, reduction in populated slices and gate minimization for DA-finite impulse response filter. This research paves a direction towards development of bio inspired computing architectures developed without logically intensive operations, obtaining the desired specifications with respect to performance, timing, and reliability.
Speed control of an SPMSM using a tracking differentiator-PID controller scheme with a genetic algorithm
Authors: Hadi Noor Hameed , Ibraheem Ibraheem Kasim
Published: February 2021

In this paper, a tracking differentiator-proportional integral and derivative (TD-PID) control scheme is proposed to control the speed of a surface mount permanent magnet synchronous motor (SPMSM). The TD is used to generate the necessary transient profile for both the reference and the output speed, which are compared with each other to produce the error signals that feed into the PID controller. In addition to the TD unit parameters, the PID controller’s parameters are tuned to achieve the optimum new multi-objective performance index, comprised of the integral of the time absolute error (ITAE), the absolute square of the control energy signal (USQR), and the absolute value of the control energy signal (UABS) and utilizing a genetic algorithm (GA). A nonlinear model of the SPMSM is considered in the design and the performance of the proposed TD-PID scheme was validated by comparing its performance with that of a traditional PI controller in a MATLAB environment. Different case studies were tested to show the effectiveness of the proposed scheme, results including peak overshoot, energy consumption, control signal chatter, and 30% improvement in the OPI, with variable reference speeds, load torque, and parameters uncertainties. Illustrate the proposed scheme's success compared with PI controller.
Grid search of multilayer perceptron based on the walk-forward validation methodology
Authors: Ngoc Tran Thanh , Dai Le Van , Phuc Dang Thi
Published: February 2021

Multilayer perceptron neural network is one of the widely used method for load forecasting. There are hyperparameters which can be used to determine the network structure and used to train the multilayer perceptron neural network model. This paper aims to propose a framework for grid search model based on the walk-forward validation methodology. The training process will specify the optimal models which satisfy requirement for minimum of accuracy scores of root mean square error, mean absolute percentage error and mean absolute error. The testing process will evaluate the optimal models along with the other ones. The results indicated that the optimal models have accuracy scores near the minimum values. The US airline passenger and Ho Chi Minh city load demand data were used to verify the accuracy and reliability of the grid search framework.