bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrahigh energy storage in superparaelectric relaxor ferroelectrics
Authors: Pan Hao , Lan Shun , Xu Shiqi , Zhang Qinghua , Yao Hongbao , Liu Yiqian , Meng Fanqi , Guo Er-Jia , Gu Lin , Yi Di , Renshaw Wang Xiao , Huang Houbing , MacManus-Driscoll Judith L. , Chen Long-Qing , Jin Kui-Juan , Nan Ce-Wen , Lin Yuan-Hua
Published: September 2021

Minimal domains for maximum energy

Dielectric capacitors are important electronic components that can store energy, at least for a short period of time. Pan
et al
. used phase-field simulations to help determine the right combination of bismuth iron oxide, barium titanium oxide, and samarium doping that is likely to generate a material with excellent dielectric properties (see the Perspective by Chu). The simulations guide a set of experimental measurements showing this system can produce a very high-energy storage by breaking down polar domains to the nanometer scale. These materials could be useful for high-power applications and to suppress failure. —BG
Single-cell nuclear architecture across cell types in the mouse brain
Authors: Takei Yodai , Zheng Shiwei , Yun Jina , Shah Sheel , Pierson Nico , White Jonathan , Schindler Simone , Tischbirek Carsten H. , Yuan Guo-Cheng , Cai Long
Published: September 2021

Nuclear organization in the brain

The brain consists of different cell types, neurons and glial cells, that have different nuclear architecture. Takei
et al
. used multiplexed imaging tools to examine the spatial arrangement of more than 3000 DNA loci, along with epigenetic marks and gene expression patterns, simultaneously in the same single cells in mouse brain cortex. They observed features that are conserved across cell types, as well as cell-type-dependent spatial arrangements at the megabase level. At the level of tens of kilobases, they observed similar single-cell chromosome domain conformations in both active and inactive X chromosomes that are averaged out in population-based measurements. —DJ
Immune signatures underlying post-acute COVID-19 lung sequelae
Authors: Cheon I. S. , Li C. , Son Y. M. , Goplen N. P. , Wu Y. , Cassmann T. , Wang Z. , Wei X. , Tang J. , Li Y. , Marlow H. , Hughes S. , Hammel L. , Cox T. M. , Goddery E. , Ayasoufi K. , Weiskopf D. , Boonyaratanakornkit J. , Dong H. , Li H. , Chakraborty R. , Johnson A. J. , Edell E. , Taylor J. J. , Kaplan M. H. , Sette A. , Bartholmai B. J. , Kern R. , Vassallo R. , Sun J.
Published: September 2021

Respiratory tissue resident–like CD8
+
T cells are associated with chronic lung sequelae post-acute COVID-19.
Conjunctional Concepts: The Conceptual Teaching Technique in Biology Classes
Authors: Zaitsev Igor V.
Published: September 2021

Conceptual teaching relies on concepts in conjunction with a bigger conceptual category (or categories). Revealing and using conceptual conjunctions in the science classroom means teaching conceptually.
Classroom Management Strategies to Improve Learning Experiences for Online Courses
Authors: Hariharan Janani , Merkel Susan
Published: September 2021

Hybrid classrooms (taught simultaneously to both in-person and online students) have become increasingly common in the course of the coronavirus disease 2019 (COVID-19) pandemic, and they have offered multiple benefits and challenges. We offer several recommendations to improve student engagement and classroom experience in such classrooms, especially for online learners who may face greater barriers to participation.
Genome Sequences of the Delta Variant (B.1.617.2) and the Kappa Variant (B.1.617.1) Detected in Morocco
Authors: Melloul Marouane , Chouati Taha , Hemlali Mouhssine , Alaoui Amine Sanaa , Touil Nadia , Elannaz Hicham , Ennibi Khalid , Youbi Mohammed , Merabet Mouad , Bellefquih Abdelkrim Meziane , Nourlil Jalal , Maaroufi Abderrahmane , El Fahime Elmostafa
Published: September 2021

Here, we report the identification and coding-complete genome sequences of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains obtained from patients with COVID-19. The variants identified belong to variant of concern B.1.617.2 and variant of interest B.1.617.1
Late Quaternary geochronologic record of soil formation and erosion: Effects of climate change on Mojave Desert hillslopes (Nevada, USA)
Authors: Persico L.P. , McFadden L.D. , McAuliffe J.R. , Rittenour T.M. , Stahlecker T.E. , Dunn S.B. , Brody S.A.T.
Published: September 2021

Climate change is an often-cited control on geomorphic processes in the arid southwestern United States, but links to direct climatic factors and vegetation change remain under debate. Hillslopes at a site in the eastern Mojave Desert in southern Nevada are mantled by 0–1.5 m of colluvial deposits. Accumulation of weathered bedrock combined with eolian inputs of fine sand and silt led to the formation of well-developed soil profiles. Surface sediments from both sources were incorporated into colluvium, allowing both processes to be dated with optically stimulated luminescence (OSL). OSL ages indicate a period of increased colluviation in the Late Pleistocene facilitated by enhanced bedrock weathering and dust deposition. Hillslope aspect strongly controls predominant soil environments and associated vegetation. Well-developed soils with dense grass cover extensively mantle the mesic north-aspect hillslopes, while more xeric south-aspect hillslopes are dominated by thin colluvium with minimal soil development, extensive bedrock exposure, and desertscrub vegetation. Remnants of older colluvium with moderately developed soils on south aspects, however, indicate they were once more extensively mantled by thicker colluvial deposits. The transition to drier conditions in the Holocene diminished vegetation cover on more xeric south aspects, triggering widespread erosion, whereas the more mesic north aspects retained denser grass cover that minimized erosion. The transition to drier conditions in the Holocene altered the vegetation; however, persistent perennial grass cover minimized erosion into the middle Holocene. Increasing aridity during the middle Holocene significantly reduced grass cover on more xeric south aspects, triggering erosion and alluvial deposition. OSL dates of dust incorporated into terrace sediments indicate late Middle Holocene aggradation and soil development in the Late Holocene. In contrast, maintenance of substantial perennial grass cover on mesic north aspects minimized erosion from those hillslopes throughout the Holocene.
Unexpected cause of dyspnoea in a patient with allergic rhinitis
Authors: Vukičević Lazarević Vesna , Šola Ana Marija , Vlahović Ivan
Published: September 2021

A defect in one part of the immune system may affect the whole system. As a result, there may be a myriad of immunological diseases, which are often masked with the one disease that has the most prominent symptoms. This case report presents a patient with long-lasting allergic rhinitis who recently developed dyspnoea in exertion with suspected asthma development. After extensive diagnostic processing, asthma was dismissed, and diagnosis of selective IgA deficiency and coeliac disease with consequential iron deficiency anaemia was established. The patient was treated with parenteral iron and a gluten-free diet, which corrected her anaemia and led to the disappearance of dyspnoea. This paper aims to show the interplay between different immunological disorders and the possible causal connection between them.
New insights into change of lens proteins’ stability with ageing under physiological conditions
Authors: Luo Chenqi , Xu Jingjie , Fu Chenxi , Yao Ke , Chen Xiangjun
Published: September 2021

Background

Age-related cataract, which presents as a cloudy lens, is the primary cause of vision impairment worldwide and can cause more than 80% senile blindness. Previous studies mainly explored the profile of lens proteins at a low concentration because of technical limitations, which could not reflect physiological status. This study focuses on protein stability changes with ageing under physiological conditions using a novel equipment, Unchained Labs (Uncle), to evaluate protein thermal stability.

Methods

Samples were assessed through Unchained Labs, size-exclusion chromatography, western blot and biophysics approaches including the Thioflavin T, ultraviolet and internal fluorescence.

Results

With age, the melting temperature value shifted from 67.8°C in the young group to 64.2°C in the aged group. Meanwhile, crystallin may form more isomeric oligomers and easy to be degraded in aged lenses. The spectroscopic and size-exclusion chromatography results show a higher solubility after administrated with lanosterol under the environmental stress.

Conclusion

We are the first to explore rabbit lens protein stability changes with ageing using biophysical methods under physiological conditions, and this study can conclude that the structural stability and solubility of lens proteins decrease with ageing. Additionally, lanosterol could aid in resolving protein aggregation, making it a potential therapeutic option for cataracts. So, this study provides cataract models for anti-cataract drug developments
Do physical interventions improve outcomes following concussion: a systematic review and meta-analysis?
Authors: Reid Susan A , Farbenblum Joshua , McLeod Shreya
Published: September 2021

Objective

To investigate the effect of physical interventions (subthreshold aerobic exercise, cervical, vestibular and/or oculomotor therapies) on days to recovery and symptom scores in the management of concussion.

Design

A systematic review and meta-analysis.

Data sources

Medline, CINAHL, Embase, SportDiscus, Cochrane library, Scopus and PEDro.

Eligibility criteria

Randomised controlled trials of participants with concussion that evaluated the effect of subthreshold aerobic exercise, cervical, vestibular and/or oculomotor therapies on days to recovery/return to activity, symptom scores, balance, gait and/or exercise capacity.

Results

Twelve trials met the inclusion criteria: 7 on subthreshold aerobic exercise, 1 on vestibular therapy, 1 on cervical therapy and 3 on individually tailored multimodal interventions. The trials were of fair to excellent quality on the PEDro scale. Eight trials were included in the quantitative analysis. Subthreshold aerobic exercise had a significant small to moderate effect in improving symptom scores (standardised mean difference (SMD)=0.43, 95% CI 0.18 to 0.67, p=0.001, I2=0%) but not in reducing days to symptom recovery in both acutely concussed individuals and those with persistent symptoms (SMD=0.19, 95% CI −0.54 to 0.93, p=0.61, I2=52%). There was limited evidence for stand-alone cervical, vestibular and oculomotor therapies. Concussed individuals with persistent symptoms (>2 weeks) were approximately 3 times more likely to have returned to sport by 8 weeks (relative risk=3.29, 95% CI 0.30 to 35.69, p=0.33, I2=83%) if they received individually tailored, presentation-specific multimodal interventions (cervical, vestibular and oculo-motor therapy). In addition, the multimodal interventions had a moderate effect in improving symptom scores (SMD=0.63, 95% CI 0.11 to 1.15, p=0.02, I2=0%) when compared with control.

Conclusions

Subthreshold aerobic exercise appears to lower symptom scores but not time to recovery in concussed individuals. Individually tailored multimodal interventions have a worthwhile effect in providing faster return to sport and clinical improvement, specifically in those with persistent symptoms.

PROSPERO registration number

CRD42020108117.
Association between hepatic fat and subclinical vascular disease burden in the general population
Authors: Cai Xinting , Rospleszcz Susanne , Mensel Birger , Schminke Ulf , Kühn Jens-Peter , Aghdassi Ali Alexander , Storz Corinna , Lorbeer Roberto , Schlett Christopher L , Rathmann Wolfgang , Roden Michael , Hohenester Simon , Bülow Robin , Bamberg Fabian , Peters Annette , Thorand Barbara , Völzke Henry , Nano Jana
Published: September 2021

Objective

It is still controversial if increased hepatic fat independently contributes to cardiovascular risk. We aimed to assess the association between hepatic fat quantified by MRI and various subclinical vascular disease parameters.

Design

We included two cross-sectional investigations embedded in two independent population-based studies (Study of Health in Pomerania (SHIP): n=1341; Cooperative Health Research in the Region of Augsburg (KORA): n=386). The participants underwent a whole-body MRI examination. Hepatic fat content was quantified by proton-density fat fraction (PDFF). Aortic diameters in both studies and carotid plaque-related parameters in KORA were measured with MRI. In SHIP, carotid intima-media thickness (cIMT) and plaque were assessed by ultrasound. We used (ordered) logistic or linear regression to assess associations between hepatic fat and subclinical vascular disease.

Results

The prevalence of fatty liver disease (FLD) (PDFF >5.6%) was 35% in SHIP and 43% in KORA. In SHIP, hepatic fat was positively associated with ascending (β, 95% CI 0.06 (0.04 to 0.08)), descending (0.05 (0.04 to 0.07)) and infrarenal (0.02 (0.01 to 0.03)) aortic diameters, as well as with higher odds of plaque presence (OR, 95% CI 1.22 (1.05 to 1.42)) and greater cIMT (β, 95% CI 0.01 (0.004 to 0.02)) in the age-adjusted and sex-adjusted model. However, further adjustment for additional cardiometabolic risk factors, particularly body mass index, attenuated these associations. In KORA, no significant associations were found.

Conclusions

The relation between hepatic fat and subclinical vascular disease was not independent of overall adiposity. Given the close relation of FLD with cardiometabolic risk factors, people with FLD should still be prioritised for cardiovascular disease screening.
Proteinuria in hospitalised internal medicine adult patients
Authors: Shimoni Zvi , Froom Paul , Benbassat Jochanan
Published: September 2021

Rationale

Dipstick proteinuria may be a sign of a renal disorder, false-positive or associated with acute disease, and consequently, transient in hospitalised patients.

Objective

To assess (a) the prevalence of proteinuria in hospitalised patients; (b) its association with estimated glomerular filtration rate (eGFR), findings known to cause false-positive test results and indicators of acute disease and (c) the need for follow-up after discharge.

Setting and participants

All patients who had a dipstick urinalysis on admission to medical wards of a 400-bed regional hospital in 2018–2019.

Outcome variable

Proteinuria.

Independent variables

(a) Other findings on dipstick urinalysis; (b) patients' age, gender, presence of urinary catheter and eGFR and (c) white blood cell count (WBC) and fever.

Results

Of 22 329 patients, 6609 (29.6%) had urinalysis. Of those, 2973 patients (45.0%) had proteinuria of ≥+1 (≥0.30 g/L). The variables independently associated with proteinuria were other dipstick findings known to cause false-positive test results, elevated WBC, fever on presentation, presence of a urethral catheter and a low eGFR. eGFR alone was a poor predictor of proteinuria (c-stat 0.62); however, addition of the remaining independent variables to the model significantly improved its predictive ability (c-stat 0.80).

Conclusions

Dipstick proteinuria is common in hospitalised patients. Although weakly associated with eGFR, proteinuria is mainly associated with confounding factors that may result in false-positive test results. The need for follow-up of proteinuria after discharge has questionable clinical utility and its high frequency would entail a considerable cost.
Epinephrine (adrenaline) compared to selective beta-2-agonist in adults or children with acute asthma: a systematic review and meta-analysis
Authors: Baggott Christina , Hardy Jo Katherine , Sparks Jenny , Sabbagh Doñah , Beasley Richard , Weatherall Mark , Fingleton James
Published: September 2021

Background

International asthma guidelines recommend against epinephrine (adrenaline) administration in acute asthma unless associated with anaphylaxis or angio-oedema. However, administration of intramuscular epinephrine in addition to nebulised selective β2-agonist is recommended for acute severe or life-threatening asthma in many prehospital guidelines. We conducted a systematic review to determine the efficacy of epinephrine in comparison to selective β2-agonist in acute asthma.

Methods

We included peer-reviewed publications of randomised controlled trials (RCTs) that enrolled children or adults in any healthcare setting and compared epinephrine by any route to selective β2-agonist by any route for an acute asthma exacerbation. The primary outcome was treatment failure, including hospitalisation, need for intubation or death.

Results

Thirty-eight of 1140 studies were included. Overall quality of evidence was low. Seventeen studies contributed data on 1299 participants to the meta-analysis. There was significant statistical heterogeneity, I2=56%. The pooled Peto’s OR for treatment failure with epinephrine versus selective β2-agonist was 0.99 (0.75 to 1.32), p=0.95. There was strong evidence that recruitment age group was associated with different estimates of the odds of treatment failure; with studies recruiting adults-only having lower odds of treatment failure with epinephrine. It was not possible to determine whether epinephrine in addition to selective β2-agonist improved outcomes.

Conclusion

The low-quality evidence available suggests that epinephrine and selective β2-agonists have similar efficacy in acute asthma. There is a need for high-quality double-blind RCTs to determine whether addition of intramuscular epinephrine to inhaled or nebulised selective β2-agonist improves outcome.

PROSPERO registration number

CRD42017079472.
Corticomuscular and Intermuscular Coupling in Simple Hand Movements to Enable a Hybrid Brain–Computer Interface
Authors: Colamarino Emma , de Seta Valeria , Masciullo Marcella , Cincotti Febo , Mattia Donatella , Pichiorri Floriana , Toppi Jlenia
Published: September 2021

Hybrid Brain–Computer Interfaces (BCIs) for upper limb rehabilitation after stroke should enable the reinforcement of “more normal” brain and muscular activity. Here, we propose the combination of corticomuscular coherence (CMC) and intermuscular coherence (IMC) as control features for a novel hybrid BCI for rehabilitation purposes. Multiple electroencephalographic (EEG) signals and surface electromyography (EMG) from 5 muscles per side were collected in 20 healthy participants performing finger extension (Ext) and grasping (Grasp) with both dominant and non-dominant hand. Grand average of CMC and IMC patterns showed a bilateral sensorimotor area as well as multiple muscles involvement. CMC and IMC values were used as features to classify each task versus rest and Ext versus Grasp. We demonstrated that a combination of CMC and IMC features allows for classification of both movements versus rest with better performance (Area Under the receiver operating characteristic Curve, AUC) for the Ext movement (0.97) with respect to Grasp (0.88). Classification of Ext versus Grasp also showed high performances (0.99). All in all, these preliminary findings indicate that the combination of CMC and IMC could provide for a comprehensive framework for simple hand movements to eventually be employed in a hybrid BCI system for post-stroke rehabilitation.
On Exchange Methods for Nonlinear Semi-Infinite Programs
Authors: Zhang Liping , Du Shouqiang
Published: September 2021

A new exchange method is presented for semi-infinite optimization problems with polyhedron constraints. The basic idea is to use an active set strategy as exchange rule to construct an approximate problem with finitely many constraints at each iteration. Under mild conditions, we prove that the proposed algorithm terminates in a finite number of iterations and guarantees that the solution of the resulting approximate problem at final iteration converges to the solution of the original problem within arbitrarily given tolerance. Numerical results indicate that the proposed algorithm is efficient and promising.
A data-driven epidemic model with social structure for understanding the COVID-19 infection on a heavily affected Italian province
Authors: Zanella Mattia , Bardelli Chiara , Dimarco Giacomo , Deandrea Silvia , Perotti Pietro , Azzi Mara , Figini Silvia , Toscani Giuseppe
Published: September 2021

In this work, using a detailed dataset furnished by National Health Authorities concerning the Province of Pavia (Lombardy, Italy), we propose to determine the essential features of the ongoing COVID-19 pandemic in terms of contact dynamics. Our contribution is devoted to provide a possible planning of the needs of medical infrastructures in the Pavia Province and to suggest different scenarios about the vaccination campaign which possibly help in reducing the fatalities and/or reducing the number of infected in the population. The proposed research combines a new mathematical description of the spread of an infectious diseases which takes into account both age and average daily social contacts with a detailed analysis of the dataset of all traced infected individuals in the Province of Pavia. These information are used to develop a data-driven model in which calibration and feeding of the model are extensively used. The epidemiological evolution is obtained by relying on an approach based on statistical mechanics. This leads to study the evolution over time of a system of probability distributions characterizing the age and social contacts of the population. One of the main outcomes shows that, as expected, the spread of the disease is closely related to the mean number of contacts of individuals. The model permits to forecast thanks to an uncertainty quantification approach and in the short time horizon, the average number and the confidence bands of expected hospitalized classified by age and to test different options for an effective vaccination campaign with age-decreasing priority.
LOCAL EXISTENCE AND BLOW-UP OF SOLUTIONS TO FUJITA-TYPE EQUATIONS INVOLVING GENERAL ABSORPTION TERM ON FINITE GRAPHS
Authors: WU YITING
Published: September 2021

This paper is devoted to the study of the behaviors of the solution to Fujita-type equations on finite graphs. Under certain conditions given by absorption term of the equations, we prove respectively local existence and blow-up results of solutions to Fujita-type equations on finite graphs. Our results contain some previous results as special cases. Finally, we provide some numerical experiments to illustrate the applicability of the obtained results.
FRACTAL HADAMARD–MERCER-TYPE INEQUALITIES WITH APPLICATIONS
Authors: BUTT SAAD IHSAN , YOUSAF SABA , YOUNAS MUHAMMAD , AHMAD HIJAZ , YAO SHAO-WEN
Published: September 2021

Fractal analysis is a totally new area of research based on local fractional calculus. It has interesting applications in various fields such as a complex graph, computer graphics, the music industry, picture compression and many more fields. In this paper, we present new variants of Hadamard–Mercer-type inequalities on fractal sets [Formula: see text] ([Formula: see text] by employing generalized convex function. We establish two new lemmas involving local fractional integrals. By using these lemmas, we obtain several results related to generalized Hadamard–Mercer-type integral inequalities for local differentiable generalized convex functions on real linear fractal space. Finally, we give applications for probability density functions and compute new generalized means.
SUPPLY CHAIN JOINT SCHEDULING AND ALGORITHM USING CONTINUITY OF NONLINEAR DIFFERENTIAL EQUATION FUNCTION
Authors: JIN XIN , KONG MENGLEI , HU JIYE , DENG XIAO , YU MIAO
Published: September 2021

To improve the integrity of the supply chain and get the optimal joint scheduling of the complete supply chain, in this exploration, first, the supply chain related theory is elaborated. Then, the dynamic model of product recovery in enterprise joint scheduling is established. Finally, based on the differential game theory (based on the continuity of nonlinear differential equation function) and Hamilton function, the optimal scheduling strategies with manufacturer and retailer as the main recycling body in the complete supply chain are calculated respectively. The results show that the product recovery rate with manufacturer as the main recycling body is higher than that with retailer as the main recycling body. There is no transfer price in the recovery based on the manufacturer. However, in the recovery based on the retailer, if the transfer price increases, the product recovery rate of the system will also increase; if the transfer price increases, the manufacturer’s instant profit will appropriately increase; if the transfer price value is high [Formula: see text], the manufacturer’s instant profit is higher. If the transfer payment is low [Formula: see text], the instant profit of manufacturer with manufacturer as the main recycling body will be first lower and then higher than that with retailer as the main recycling body. When the system is stable, the instant profit with the manufacturer as the main recycling body is higher than that with retailer as the main recycling body; the total profit of the manufacturer with the retailer as the recycling body is first lower and then higher than that with the manufacturer as the main recycling body. Whether the transfer payment is high or low, the retailer’s profit level is higher when the manufacturer is the main recycling body. When the retailer is the main recycling body, the retailer’s profit level is inversely proportional to the transfer payment. Finally, in the centralized supply chain environment, enterprises can maximize their total profits and promote the good development.
FINANCIAL MANAGEMENT OF ASSET-LIABILITY RATIO OF SMALL- AND MEDIUM-SIZED ENTERPRISES IN DYNAMIC NONLINEAR SYSTEM
Authors: ZHANG LING , FAKIEH BAHJAT , SHANG LI
Published: September 2021

The purposes of this paper are to optimize the financial management methods of small- and medium-sized enterprises (SEMs) and deeply explore asset-liability ratio’s relevant theories. A medium-sized manufacturing enterprise’s financial conditions and the influencing factors of enterprise’s asset-liability ratio are researched by a dynamic model with two-way effects and the enterprises’ dynamic nonlinear simulation model. Meanwhile, capital injection’s impacts on asset-liability ratio are explored. The results show that different industries’ enterprise asset-liability ratios vary. The real estate enterprises’ asset-liability ratio is 61.35%, the highest, and the cultural communication industry is the lowest, 35.62%. Meanwhile, the asset-liability ratios of energy industry, manufacturing industry, and the wholesale and retail industry are also relatively high. The larger the enterprise’s scale, the higher its asset-liability ratio, long-term liability ratio, current liability ratio, and loan financing. The proposed simulation software performs satisfactorily in its application. The simulation system’s analysis shows that the target enterprise’s asset-liability ratio is gradually increasing, and its return on equity and capital turnover rate is decreasing, reaching the critical bankruptcy point in the 36th month. With a 20 million CNY capital injection, its asset-liability ratio decreases significantly, and return on equity increases steadily. In the 49th month, it resumes normal operations. The results provide a useful reference for subsequent research on enterprises’ asset-liability ratios and SMEs’ financial management.
THE DEMODULATION ALGORITHM OF OPTICAL FIBER FABRY–PEROT SENSOR USING THE NONLINEAR DYNAMIC CHARACTERISTICS OF THE OPTICAL FIBER BROADBAND LIGHT SOURCE
Authors: FENG FEI , CHEN BAOJIE , ALSHEHRI HASHIM M. , LIU YINGBIN , QIN LI
Published: September 2021

The purpose is to optimize the optical fiber Fabry–Perot (F-P) sensor’s performances to provide a realistic basis for the optical fiber’s development. First, the classification of the optical fiber F-P sensors is summarized. The optical fiber F-P sensors’ fundamental principles are analyzed, focusing on the phase demodulation method that converts the optical fiber F-P sensing system’s input light source into a broadband light source. The broadband light source’s lightwave changes are analyzed, and the Fourier transform method and the fringe counting method are proposed to optimize the phase demodulation method’s function and analyze the light source’s nonlinear dynamic characteristics. According to the proposed demodulation method, the optical fiber F-P sensor with a cavity length change of [Formula: see text][Formula: see text][Formula: see text]m is simulated, and the cavity length selected for the simulation spectrum is the change range’s center value, 185[Formula: see text]um. The wavelength division multiplexer (WDM) decomposes the two optical signals, and an equation directly calculates the wavelength value orthogonal to its phase. The results show that the light intensity’s initial value of the actual spectrum is 0.04, and that of the standard function is 0.06. The light intensities for the maximum peak values are the same, 0.12, with the wavelength in [Formula: see text]–[Formula: see text][Formula: see text]m. When the wavelength exceeds [Formula: see text][Formula: see text]m before the next peak, the light intensity difference between them is large. The two orthogonal optical signals’ peaks change between the cavity length 0.18[Formula: see text]nm and 0.19[Formula: see text]nm after the wavelength selected, and the two signals’ peak values are orthogonal with the cavity length changes. The two signals’ initial and end peak values are different. The curve obtained by the two signals division calculation shows a tangent trend with the highest peak value of 87 and the lowest of [Formula: see text]. The peak curve changes obtained by the two signals’ arctangent calculation are in an orthogonal state, with the maximum peak value of 1.3 and the minimum of [Formula: see text]. The reflected light peak value changes of the optical fiber F-P sensor are in an orthogonal state, with the highest value of [Formula: see text] and the lowest [Formula: see text], and the adjacent peak changes in the wavelengths of 1500–1580 are the same. The curve’s fitting linearity is 1, and the linearity in the dynamic demodulation is 0.9776. The sampling frequency in the phase demodulation is [Formula: see text][Formula: see text]Hz, and the sampling frequency in the dynamic demodulation is [Formula: see text][Formula: see text]Hz, showing that upgrading the interface can increase the dynamic sampling frequency continuously to improve the device performance.
PSYCHOLOGICAL MEMORY FORGETTING MODEL USING LINEAR DIFFERENTIAL EQUATION ANALYSIS
Authors: GUO JIANFANG , ALBESHRI AIIAD A. , SANCHEZ YOLANDA GUERRERO
Published: September 2021

To solve the problem of insufficient combination of neural mechanism and psychological mechanism in the study of human brain cognitive memory activity, in this exploration, the memory forgetting model in psychology is analyzed and constructed by fractional order model of linear differential equation. The study of memory in cognitive psychology is combined with the neurophysiological mechanism of memory. At the same time, for the stability of long-term memory, a long-term memory neural network model (LTMNNS) is proposed. The validity and accuracy of the model are tested by the recognition of memory eigenvectors. Numerical test and simulation results show that when the difference between any initial values of the system is not more than [Formula: see text], the corresponding system solution difference is not more than [Formula: see text] in the interval [Formula: see text]. Reasoning correctness of fractional order computation model of memory neural network is verified. The LTMNNS algorithm in this exploration guarantees a high number of completed tasks, and the average number of failed tasks is less than MemNNs, DNC and LSTM algorithm. Compared with other models, the proposed LTMNNS has better generalization ability and higher stability.
INVESTIGATION OF ENGLISH GRAMMAR APPLICATION ABILITY OF COLLEGE STUDENTS USING DYNAMIC NONLINEAR SYSTEM THEORY
Authors: JIANG LINGLIN , ALOTAIBI FAHD S.
Published: September 2021

The purpose of this paper is to improve the English teaching levels of colleges and universities. First, the primary attributes of dynamic nonlinear system theory in second language acquisition are analyzed. Second, the influencing factors of English grammar application ability in theoretical dimension and measurement methods are proposed. Six first-year students majoring in English in a university were randomly selected as research objects, who were followed up for a semester, during which three identical oral English tasks were finished (in September, October, and November of 2020). The fluency, accuracy, and complexity of students’ utterances are statistically analyzed using SPSS 26.0. Results demonstrate that the fluency of students’ utterances has increased from 110 syllables per minute on average in September to 129 syllables per minute on average in November. The proportion of error-free clauses has increased from 0.5 to 0.55, and the number of clauses in the T unit has increased from 1.42 to 1.51. Students [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text] have a gradually increasing accuracy of utterance, while student [Formula: see text] shows a gradually decreasing utterance accuracy. Students [Formula: see text] and [Formula: see text] have a decreasing utterance accuracy, while students [Formula: see text] and [Formula: see text] present an increasing utterance accuracy. Besides, the utterance accuracy of students [Formula: see text] and [Formula: see text] first decreases and then increases. The performances in utterance complexity of students [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text] have been increasing gradually, while the performance of student [Formula: see text] has been decreasing gradually. The normal distribution of each student’s test scores is different, as well. Hence, any minor changes will affect the overall oral English levels of students.
PREFERENCE AGGREGATION MODEL CONSTRUCTION OF GROUP MANAGEMENT DECISION-MAKING BASED ON RELATIVE ENTROPY AND NORM OPERATOR
Authors: WANG TINGZHI , MA XIAOXIA , BARNAWI AHMED , SARKER MD NAZIRUL ISLAM , LIAO YONGLIN
Published: September 2021

Due to the complexity of the problem in the actual group management decision, the ambiguity of the information of all parties and the uncertainty of the decision environment, it is often difficult for decision-makers to describe the decision information by quantitative methods, but to give uncertain linguistic variables. Based on the analysis of previous research results, this paper proposes a group management decision-making aggregation model based on relative entropy and norm operator. First, the model uses the operation of [Formula: see text]-norm and new [Formula: see text]-norm operator to make the fuzzy set satisfy the ranking rate and contradiction rate. Then, based on the reliability of relative entropy, the attribute weights of different expert decisions are obtained, and the optimal assembly model of the corresponding group decision is established, respectively. The optimal solution and decision algorithm are given for each optimization model. The last example of the algorithm proves the validity and feasibility of the model, and can effectively avoid the distortion and distortion in the process of group management decision preference aggregation.
PRACTICE AND DEVELOPMENT OF SPORTS SOMATIC SCIENCE IN SOCIAL PHYSICAL EDUCATION TEACHING USING FRACTAL THEORY
Authors: WAN LISHUANG , ALQURASHI FAHAD ABDULLAH , JUNG WOO-JIN
Published: September 2021

In view of the recognition of human motion function in physical education, a multidimensional evaluation index of motion function based on fatigue, muscle strength and muscle contraction, and relaxation ability is proposed, and the mapping rules among fatigue characteristic value, muscle strength, fractal dimension characteristic change, and motion function state are studied. Based on the characteristics of surface electromyography (sEMG) signal and its generating principle, the collected signal is preprocessed by median filtering to obtain the filtered signal. The effectiveness of the filtering method is proved by comparing the signals before and after filtering. The current muscle strength calculation method based on sEMG signal is analyzed and studied. The muscle strength calculation method of Hill three-element model is used to establish the muscle model through the muscle activity and force–length curve calculated by sEMG signals. The muscle strength is obtained by muscle model, and the feasibility of the experimental method is verified by comparing the calculated actual muscle strength with the theoretical muscle strength. In the experiment, the distribution of different subjects in the multidimensional evaluation index space is studied. Moreover, the mapping relationship between sEMG signal characteristics and human motion function is discussed comprehensively based on theory and data.
DESIGN OF DYNAMIC NONLINEAR INTELLIGENT CONTROL SYSTEM FOR SIGNAL PROCESSING
Authors: WANG ZHIYOU , CHEN YING , ALSEMMEARI RAYANATTEAH , ZHOU YUAN
Published: September 2021

Based on back propagation neural network (BPNN), we design a dynamic nonlinear intelligent control system for signal processing and analysis in this work. Performances of the traditional PID and BPNN control systems is compared in a case of heat power engineering system design. In the design, the training times, regulation time of the BPNN control system are evaluated when [Formula: see text] and [Formula: see text], respectively. Furthermore, the regulation time, oscillation time and amplitude of the traditional PID and BPNN control systems are compared in the dead zone. Results of the comparison show that the BPNN based dynamic nonlinear intelligent control system demonstrates superior performances over the traditional PID control system. The research results prove the advantage of BPNN in the design of nonlinear control systems and provide a scientific and effective reference for the follow-up research works.
PARAMETER-VARYING ARTIFICIAL POTENTIAL FIELD CONTROL OF VIRTUAL COUPLING SYSTEM WITH NONLINEAR DYNAMICS
Authors: CAO YUAN , WEN JIAKUN , HOBINY AATEF , LI PENG , WEN TAO
Published: September 2021

In rail transit systems, improving transportation efficiency has become a research hotspot. In recent years, a new method of train control system based on virtual coupling has attracted the attention of many scholars. Virtual coupled train is a typical nonlinear system. How to control the nonlinear system with high precision is the key to realize the safe and efficient operation of virtual coupled train. Therefore, this paper proposes a virtual coupling scheme based on local leader–follower method. On this basis, the controller based on artificial potential field with variable parameter mixed is applied to carry out the collaborative and anti-collision control for the virtual coupled train system with nonlinear dynamics. Finally, a section of the Beijing–Shanghai high-speed railway is taken as the background to verify the effectiveness of artificial potential field with variable parameter mixed controller. The results show that the variable parameter artificial potential field controller with changing the weight can reduce the average error of the stop by 0.4304[Formula: see text]m compared with the traditional controller.
SIMULATION OF FUZZY NEURAL NETWORK ALGORITHM IN DYNAMIC NONLINEAR SYSTEM
Authors: ZENG JUN , ALASSAFI MADINI O. , SONG KE
Published: September 2021

The identification of nonlinear system is studied to establish an accurate model of coordination system. The original dynamic fuzzy neural network (DFNN) is first used to identify the nonlinear system for finding the existing problems. Aiming at the problems found, two improvements are made. For the problem of too many pre-set parameters in the original algorithm, the fuzzy completeness [Formula: see text] is introduced to allocate the parameters, and the width of the membership function is modified. The simulation results reveal that the fuzzy neural network (FNN) model not improved produces seven fuzzy rules, and the root mean square error (RMSE) of training is 0.0261, while the improved FNN model produces six fuzzy rules, and the RMSE of training is 0.0161. The improved network has more advantages in performance. The model proposed provides some references for the application of FNN in dynamic nonlinear systems.
Generalized Lindley Shared Frailty Based on Reversed Hazard Rate
Authors: Pandey Arvind , Hanagal David D. , Tyagi Shikhar , Gupta Pragya
Published: September 2021

Due to the unavailability of complete data in various circumstances in biological, epidemiological, and medical studies, the analysis of censored data is very common among practitioners. But the analysis of bivariate censored data is not a regular mechanism because it is not necessary to always have independent data. Observed and unobserved covariates affect the variables under study. So, heterogeneity is present in the data. Ignoring observed and unobserved covariates may have objectionable consequences. But it is not easy to find that whether there is any effect of the unobserved covariate or not. Shared frailty models are the viable choice to counter such scenarios. However, due to certain restrictions such as the identifiability condition and the requirement that their Laplace transform exists, finding a frailty distribution can be difficult. As a result, in this paper, we introduce a new frailty distribution generalized Lindley (GL) for reversed hazard rate (RHR) setup that outperforms the gamma frailty distribution. So, our main motive is to establish a new frailty distribution under the RHR setup. By assuming exponential Gumbel (EG) and generalized inverted exponential (GIE) baseline distributions, we propose a new class of shared frailty models based on RHR. We estimate the parameters in these frailty models and use the Bayesian paradigm of the Markov Chain Monte Carlo (MCMC) technique. Model selection criteria have been performed for the comparison of models. We analyze Australian twin data and suggest a better model.
ASSESSING THE TRIBOLOGICAL PROPERTIES OF VEGETABLE OIL EMULSIONS AND MACHINING PARAMETER OPTIMIZATION USING RESPONSE SURFACE METHODOLOGY
Authors: KARUPANNASAMY D. K. , SAMBATHKUMAR M. , GUKENDRAN R. , SASIKUMAR K. S. K. , BAASKARAN N. , SHANKAR S.
Published: September 2021

Bio-degradable lubricants are the need for industries to promote eco-friendly manufacturing process and protect the workers from health hazards. In this paper, the use of oil–water emulsions from the bio-substitute oils have been formulated and its process parameter on a machining process are optimized using response surface methodology. The emulsions are prepared from the vegetable oils such as castor, mahua, palm and neem oil with polysorbate as emulsifying agent. The friction and wear characteristics are studied with a standard pin on disc tribometer for all the emulsions prepared with the base oils namely castor, mahua and palm oil. From the tribological characterization tests, the castor oil emulsions have shown better performance and stability in comparison to other oils. Hence, castor oil emulsions have been tested for its machining performance studies against a conventional mineral oil emulsion in a turning process. Further, an emulsion based on castor oil and neem oil have been tested for tool wear to utilize the antimicrobial properties of neem oil for reducing the bio fouling effects. The machining performance is indicated based on the surface finish and tool wear. Response surface methodology have been used for optimization of the machining parameters, such as cutting velocity, feed rate and depth of cut to achieve an optimal surface finish for a maximum material removal rate. The results show that the castor oil based emulsion can be used as an excellent alternative for mineral oil emulsions.
Three-Dimensional Vehicle–Curved Track Dynamic Model Based on FEM and DEM
Authors: Chen Xianmai , Pan Liu , Xu Lei , Shi Can
Published: September 2021

In this work, a systematic vehicle–curved track dynamic model is presented, in which the vehicle is modeled as a multi-rigid-body system. The track structure is modeled by finite element method with curved rail beam element considered in geometry. To obtain accurate dynamic behavior of railway ballasted track, the resistance characteristics of ballast bed are revealed by introducing the discrete element method. Besides, a two-step iterative-update method is improved to solve the multi-nonlinearity of the vehicle–curved track dynamic interaction. To improve the computational efficiency, and the improved infinite cyclic calculation method is introduced. Apart from the model validations, the application of this model in engineering practices, such as the vehicle-induced vibration of the continuously welded rail (CWR), has been revealed, and some conclusions are drawn from the numerical studies.
Ring of flows of one-dimensional differential equations
Authors: Orozco Ronald
Published: September 2021

In this paper, we construct a ring of flows, where we can decompose one-dimensional autonomous differential equations into smaller parts, then solve each part and finally put everything together to obtain the exact solution of these equations.
Synthesis and Characterization of Nanocrystalline Ba-doped Mn3O4 Hausmannite Thin Films for Optoelectronic Applications
Authors: Najim Aus A. , Gbashi Kadhim R. , Salih Ammar T.
Published: September 2021

In the present work, nanocrystalline hausmannite Mn3O4:Ba thin films have been deposited on glass substrates by chemical spray pyrolysis (CSP). Then, we investigated the impact of Ba doping concentrations on the structural, morphological and optical properties. The structural characteristics were investigated by X-ray diffraction technique and clearly show the films have a spinel Mn3O4 polycrystalline structure, the degree of crystallinity was improved by increasing Ba concentrations in Mn3O4 matrix with crystallite size range of 15–33[Formula: see text]nm. The lattice parameters, the unit cell volume and the (Mn-O) bond length of tetrahedral and octahedral sites, were varied by increasing Ba concentrations. SEM micrographs show that the films are homogeneous with nanoparticles dispersed on the surface with sizes range 30–132[Formula: see text]nm. The optical properties were estimated by UV-Vis-NIR spectrophotometer and exhibited that the optical transmittance and band gap were improved by increasing Ba doping concentration. Empirical equations were suggested to estimate some correlated variables with excellent agreement with the experimental data. The optimum condition was recorded in films doped with 3% of Ba where a better crystallinity, a preferable surface morphology and outstanding optical properties have been achieved.
A Multi-Objective Mathematical Model for Level of Repair Analysis with Lead Times and Multi-Transportation Modes
Authors: Bıçakcı İsmail , İç Yusuf Tansel , Karasakal Esra , Dengiz Berna
Published: September 2021

In the event of failure of the product, level of repair analysis (LORA) is used to determine (1) whether the defective component should be discarded or repaired and (2) where this repair is made. In the literature, these repair operations are made with the aim of minimizing the total life cycle cost of the product. In this paper, we develop a multi-objective decision model that minimizes both the repair time (affected by lead times) and the repair costs. Our proposed model also considers the movement of the defective components to be performed by multiple transportation modes such as highway, railway, and airway. We use the epsilon constraint method to generate the Pareto frontier and analyze the trade-off between total repair costs and total repair time. We demonstrate the approach on an example problem.