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Journal of Systems Science and Systems Engineering 2024年第2期33卷 187-206页

作者： Mintu kumar Himani pant S.B.Singh Department of Mathematics Statistics and Computer Science G.B.Pant University of AgricultureTechnologyPantnagarUttarakhandIndia

Uncertainty is an important factor that needs to be considered while analyzing the performance of any engineering *** order to quantify uncertainty,fuzzy set theory is frequently used by most of researchers,including energy system *** to the classical reliability theory,component lifetimes have crisp parameters,but due to uncertainty and inaccuracy in data,it is sometimes very difficult to determine the exact values of these parameters in real-world *** overcome this difficulty in the current research,failure and repair rates were taken as triangular fuzzy numbers to determine the fuzzy availability of a system undergoing calendar-based periodic inspection subject to multiple failure modes(FMs).It was assumed that each component in the system had an exponential failure rate and repair rate with fuzzy *** FMs were explicitly taken into account when a functional state of the system was *** FM had a random failure *** the occurrence of any failure,a random time was selected for the relevant corrective repair *** proposed research was studied for one of the major sources of green energy,namely a wind turbine system wherein all the derived propositions have been implemented on it.

关键词： Fuzzy reliability fuzzy availability wind turbine system multiple failure modes triangular fuzzy number

Mathematical assessment of the roles of age heterogeneity and vaccination on the dynamics and control of SARS-CoV-2

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Infectious Disease Modelling 2024年第3期9卷 828-874页

作者： Binod pant Abba B.Gumel Department of Mathematics University of MarylandCollege ParkMD20742USA Department of Mathematics and Applied Mathematics University of PretoriaPretoria0002South Africa

The COVID-19 pandemic,caused by SARS-CoV-2,disproportionately affected certain segments of society,particularly the elderly population(which suffered the brunt of the burden of the pandemic in terms of severity of the disease,hospitalization,and death).This study presents a generalized multigroup model,with m heterogeneous sub-populations,to assess the population-level impact of age heterogeneity and vaccination on the transmission dynamics and control of the SARS-CoV-2 pandemic in the United *** analysis of the model for the homogeneous case(i.e.,the model with m=1)reveal that its disease-free equilibrium is globally-asymptotically stable for two special cases(with perfect vaccine efficacy or negligible disease-induced mortality)whenever the associated reproduction number is less than *** model has a unique and globally-asymptotically stable endemic equilibrium,for special a case,when the associated reproduction threshold exceeds *** homogeneous model was fitted using the observed cumulative mortality data for the United States during three distinct waves(Waves A(October 17,2020 to April 5,2021),B(July 9,2021 to November 7,2021)and C(January 1,2022 to May 7,2022))chosen to align with time periods when the Alpha,Delta and Omicron were,respectively,the predominant variants in the United *** calibrated model was used to derive a theoretical expression for achieving vaccine-derived herd immunity(needed to eliminate the disease in the United States).It was shown that,using the one-group homogeneous model,vaccine-derived herd immunity is not attainable during Wave C of the pandemic in the United States,regardless of the coverage level of the fully-vaccinated *** sensitivity analysis was carried out to determine the parameters of the model that have the most influence on the disease dynamics and *** analyses reveal that control and mitigation strategies that may be very effective during one wave may not be so very effecti

关键词： COVID-19 SARS-CoV-2 Heterogeneous model Reproduction number Herd immunity

Disaster Risk Reduction (DRR) Education from Social Disciplinary Theoretical Perspectives

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Open Journal of Earthquake Research 2024年第1期13卷 41-83页

作者： Yagya Raj pant School of Health New Zealand School of Education Auckland New Zealand

Disaster is a social phenomenon. The occurrence and impacts of disasters including the education sector can be studied through a social problem lens. This paper draws meaning and understanding of DRR education using the sociological disciplinary framework in a detailed qualitative case study of three schools as they responded to the devastating Gorakha earthquake in 2015 and other disasters in Nepal. This paper considers the three sub-disciplines of sociology: the sociology of disaster, the sociology of education and the sociology of education governance in a development context. These sub-disciplines are nested together to analyse social, political and historical factors and their relationships which are helpful to identify risks and vulnerabilities in the education sector in Nepal. These are the major areas to explore the disaster context and needs of context-specific education acts (hereafter DRR education) to minimise the potential risks of disasters. The article concludes that the social disciplinary framework is significantly useful to analyse DRR education provisions and implications of education governance to mobilise school in disaster preparedness, response and recovery.

关键词： Sociology of Disaster Social Vulnerability Disaster Governance Education Governance Disaster Risk Reduction (DRR) Education Pluri-Scalar Education Governance

Diversity of Orchids in Terms of Their Distribution, Uses and Conservation in Annapurna Conservation Area of Nepal

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American Journal of Plant Sciences 2024年第6期15卷 422-440页

作者： Babu Lal Tiruwa Basu Dev Neupane Rabin kadariya Chiranjibi Prasad Pokheral Bijaya pant National Trust for Nature Conservation (NTNC)-Annapurna Conservation Area Project (ACAP) Pokhara Nepal Central Department of Botany Tribhuvan University Kathmandu Nepal

The Annapurna Conservation Area (ACA), the first conservation area and the largest protected area (PA) in Nepal, is incredibly rich in biodiversity. Notwithstanding this, orchids in the ACA have not been explored enough yet thus making the need for ambitious research to be carried out. Previous study only included 81 species of orchids within ACA. This study aims to update the record of species and genera richness in the ACA. In total 198 species of orchids, belonging to 67 genera (40% and 62% of the total recorded orchid species and genera in Nepal) has been recorded in ACA. This represents an increase of 144% in species and 56% in genera over the previous data. Out of the 198 species, 99 were epiphytes, 6 were holomycotrophic and 93 were terrestrial. Among the 67 genera, Bulbophyllum (17) species were dominant, followed by Dendrobium (16), Herminium (10), Coelogyne, Plantanthera (9 each), Eria, Habenaria, Oberonia (8 each), Calanthe (7), and Liparis (6). Fifty-six species were found to be ornamentally significant and 85 species medicinally significant.

关键词： Orchids Annapurna Conservation Area Diversity Distribution Uses

Nitrous oxide emissions in nonflooding period from fallow paddy fields

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Journal of Environmental Sciences 2008年第11期20卷 1335-1340页

作者： Hari k pant Department of Environmental Geographic and Geological Sciences Lehman College of the City University of New York250 Bedford Park Blvd WestBronxNY 10468US

The study was conducted to investigate the N2O emissions and dissolved N2O in the leachate during the nonflooding period in nongrowing paddy *** kinds of paddy soils were repacked to soil columns and were supersaturated with water initially and dried gradually in a greenhouse to attain the N2O emissions flux during the *** with the texture of silty clay-loam (Q and H) produced cracks during the drying of soil,but soil with the texture of silty loam (X) did not form the *** s...

关键词： nitrous oxide emission cracks soil drying paddy soil

Recharge and vulnerability assessment of groundwater resources in North west India:Insights from isotope-geospatial modelling approach

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Geoscience Frontiers 2024年第1期15卷 247-262页

作者： Annadasankar Roy Sitangshu Chatterjee Uday kumar Sinha Anil kumar Jain Hemant Mohokar Ajay Jaryal Tirumalesh keesari Harish Jagat pant Isotope and Radiation Application Division Bhabha Atomic Research CentreTrombayMumbai–400085India Homi Bhabha National Institute Mumbai 400094India Central Ground Water Board AhmedabadGujaratIndia

Recent studies indicate dwindling groundwater quantity and quality of the largest regional aquifer system in North West India,raising concern over freshwater availability to about 182 million population residing in this *** agricultural activities have resulted severe groundwater pollution in this area,demanding a systematic vulnerability assessment for proactive *** vulnerability assessment models encounter drawbacks due to subjectivity,complexity,data-prerequisites,and spatial-temporal *** study incorporates isotopic information into a weighted-overlay framework to overcome the above-mentioned limitations and proposes a novel vulnerability assessment *** isotope methodology provides crucial insights on groundwater recharge mechanisms(18O and 2H)and dynamics(3H)-often ignored in vulnerability *** characterisation of precipitation helped in establishing Local Meteoric Water Line(LMWL)as well as inferring contrasting recharge mechanisms operating in different *** aquifer(depthkernel Density Estimate(kDE)and isotope correlations.A weighted overlay isotope-geospatial model was developed combining 18O,3H,aquifer permeability,and water level *** central and northern parts of study area fall under least(0.29%)and extremely(1.79%)vulnerable zones respectively,while majority of the study area fall under moderate(42.71%)and highly vulnerable zones(55.20%).Model validation was performed using groundwater NO3-concentration,which showed an overall accuracy up to 82%.Monte Carlo Simulation(MCS)was performed for sensitivity analysis and permeability was found to be the most sensitive input parameter,followed by 3H,18O,and water *** the vulnerability map with Land Use Land Cover(LULC)and population density maps

关键词： Agricultural pollution Data scarcity Recharge mechanism Rayleigh distillation Isotope-geospatial model Vulnerability assessment

Universal silicon ring resonator for error-free transmission links

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Photonics Research 2024年第4期12卷 701-711页

作者： JUNBO ZHU WEIWEI ZHANG kE LI BHARAT pant MARTIN EBERT XINGZHAO YAN MEHDI BANAkAR DEHN T.TRAN CALLUM G.LITTLEJOHNS FUWAN GAN GRAHAM REED DAVID J.THOMSON Optoelectronics Research Centre University of SouthamptonSouthampton SO171BJUK National key Laboratory of Materials for Integrated Circuits Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China University of Chinese Academy of Sciences Beijing 100049China Peng Cheng Laboratory ShenzhenChina

We report the design, fabrication, and characterization of a universal silicon PN junction ring resonator for C band error-free communication links operated up to 50 Gb/s with co-designed optical modulation and detection performance. The universal p-n junction ring device shows co-designed detection responsivity up to 0.84 A/W, in conjunction with a modulation efficiency of -4 V·mm and>8 d B optical modulation extinction ratio, enabling C band 50 Gb/s NRZ communication link with a bit error rate≤3×10^(-12).

关键词： Gb/s resonator communication

A review:Advances in microbial remediation of trichloroethylene (TCE)

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Journal of Environmental Sciences 2010年第1期22卷 116-126页

作者： Prabhakar pant sudhakar pant Applied Research Center Florida International University Department of Biology St. Xavier's College

Research works in the recent past have revealed three major biodegradation processes leading to the degradation of trichloroethylene. Reductive dechlorination is an anaerobic process in which chlorinated ethenes are used as electron acceptors. On the other hand, cometabolism requires oxygen for enzymatic degradation of chlorinated ethenes, which however yields no benefit for the bacteria involved. The third process is direct oxidation under aerobic conditions whereby chlorinated ethenes are directly used as electron donors by microorganisms. This review presented the current research trend in understanding biodegradation mechanisms with regard to their field applications. All the techniques used are evaluated, with the focus being on various factors that influence the process and the outcome.

关键词： biodegradation trichloroethylene reductive dechlorination cometabolism direct oxidation

A relativistic model of stellar objects with core-crust-envelope division

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Research in Astronomy and Astrophysics 2021年第7期21卷 71-83页

作者： Ravindra k.Bisht Satyanarayana Gedela Neeraj pant Neeraj Tewari Department of Mathematics National Defence AcademyKhadakwaslaPune-411023India Department of Mathematics SSJ CampusKumaun UniversityAlmora-263601India Department of Physics Lajpat Rai CollegeGhaziabad-201005India

In this work, we present a cogent and physically well-behaved solution for neutron stars envisaged with a core layer having quark matter satisfying the MIT-bag equation of state(Eo S), meso layer with Bose-Einstein condensate(BEC) matter satisfying modified BEC Eo S and an envelope having neutron fluid and Coulomb liquids satisfying quadratic Eo S. All the required physical and geometrical parameters like gravitational potentials, pressures, radial velocity, anisotropy, adiabatic index, mass function, compactification factor, and gravitational and surface redshift functions show a feasible trend and are continuous with smooth variation throughout the interior and across the regions of the ***, causality condition, energy conditions, static stability criterion(using Tolman-OppenheimerVolkoff equation) and Herrera cracking stability criterion are met throughout the star. The approach seems to be resulting in more realistic and accurate modeling of stellar objects, particularly realized by us for X-ray binary stars 4 U 1608–52(M = 1.7 M_⊙, R = 9.5 km) and SAX J1808.4–3658(M = 1.2 M_⊙,R = 7.2 km). Furthermore, we have ascertained that the continuity of the stability factor in all three regions of the stars demand a smaller core. As the core region of the star increases, the stability factor becomes discontinuous at all the interfaces inside the star.

关键词： stars:interiors stars:neutron Galaxy:stellar content

Static fluid spheres admitting karmarkar condition

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Chinese Physics C 2020年第3期44卷 137-147页

作者： ksh.Newton Singh Ravindra k.Bisht S.k.Maurya Neeraj pant Department of Physics National Defence AcademyKhadakwaslaPune-411023India Department of Mathematics Jadavpur UniversityKolkata-700032India Department of Mathematics National Defence AcademyKhadakwaslaPune-411023India Department of Mathematical and Physical Sciences College of Arts and ScienceUniversity of NizwaNizwaSultanate of Oman

We explore a new relativistic anisotropic solution of the Einstein field equations for compact stars based on embedding class one *** this purpose,we use the embedding class one methodology by employing the karmarkar *** this methodology,we obtain a particular differential equation that connects both the gravitational potentials e^λ and e^ν.We solve this particular differential equation choosing a simple form of generalized gravitational potential grr to describe a complete structure of the space-time within the stellar *** determining this space-time geometry for the stellar models,we discuss thermodynamical observables including radial and tangential pressures,matter density,red-shift,velocity of sound,etc.,in the stellar *** also perform a complete graphical analysis,which shows that our models satisfy all the physical and mathematical requirements of ultra-high dense collapsed ***,we discuss the moment of inertia and M-R curve for rotating and non-rotating stars.

关键词： karmarkar's condition exact solutions compact star general relativity