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Fuzzy Reliability and Availability of System under a Calendar-based Inspection Involving Multiple Failures and Its Application to Wind Turbine System

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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

Associations of accelerometry-measured and self-reported physical activity and sedentary behavior with skeletal muscle energetics:The Study of Muscle,Mobility and Aging(SOMMA)

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Journal of Sport and Health Science 2024年第5期13卷 621-630页

作者： Yujia(Susanna)Qiao Terri L.blackwell Peggy M.Cawthon Paul M.Coen Steven R.Cummings Giovanna Distefano Samaneh Farsijani Daniel e.Forman bret H.Goodpaster Stephen b.Kritchevsky Theresa Mau Frederico G.S.Toledo Anne b.Newman Nancy W.Glynn Department of epidemiology School of Public HealthUniversity of PittsburghPittsburghPA 15261USA San Francisco Coordinating center California Pacific Medical Center Research InstituteSan FranciscoCA 94143USA Department of epidemiology and biostatistics University of CaliforniaSan FranciscoCA 94143USA Translational Research Institute AdventHealthOrlandoFL 32804USA Department of Medicine(Geriatrics and Cardiology) University of Pittsburghand GeriatricsResearchEducationand Clinical Center(GRECC)VA Pittsburgh Healthcare SystemPittsburghPA 15261USA Department of Internal Medicine Section on Gerontology and Geriatric MedicineWake Forest School of MedicineWinston-SalemNC 27109USA Division of endocrinology and Metabolism Department of MedicineUniversity of PittsburghPittsburghPA 15261USA

background:Skeletal muscle energetics decline with age,and physical activity(PA)has been shown to offset these declines in older ***,many studies reporting these effects were based on self-reported PA or structured exercise ***,we examined the associations of accelerometry-measured and self-reported PA and sedentary behavior(Sb)with skeletal muscle energetics and explored the extent to which PA and sedentary behavior would attenuate the associations of age with muscle ***:As part of the Study of Muscle,Mobility and Aging,enrolled older adults(n=879),810(age=76.4±5.0 years old,mean±SD;58%women)had maximal muscle oxidative capacity measured ex vivo via high-resolution re spirometry of permeabilized myofibers(maximal oxidative phosphorylation(maxOXPHOS))and in vivo by ^(31)phosphorus magnetic resonance spectroscopy(maximal adenosine triphosphate(ATP_(max))).Accelerometry-measured sedentary behavior,light activity,and moderate-to-vigorous PA(MVPA)were assessed using a wrist-worn ActiGraph GT9X over 7 ***-reported sedentary behavior,MVPA,and all PA were assessed with the Community Healthy Activities Model Program for Seniors(CHAMPS)*** regression models with progressive covariate adjustments evaluated the associations of sedentary behavior and PA with muscle energetics,as well as the attenuation of the age/muscle energetics association by MVP A and sedentary *** a sensitivity analysis,we also examined activPAL-measured daily step count and time spent in sedentary behavior and their associations with muscle ***:every 30 min/day more of ActiGraph-measured MVPA was associated with 0.65 pmol/(s×mg)higher maxOXPHOS and 0.012 mM/s higher ATP_(max)after adjusting for age,site/technician,and sex(ped with maxOXPHOS or ATP_(max).Meanwhile,every 30 min/day spent in ActiGraph-measured sedentary behavior was associated with 0.39 pmol/s×mg lower maxOXPHOS and0.

关键词： Aging exercise Mitochondria

Optimal Control of Service Rates of Discrete-Time(s,Q)Queueing-Inventory Systems with Finite buffer

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Journal of Systems Science and Systems engineering 2024年第3期33卷 261-280页

作者： L.Iniya b.Sivakumar G.Arivarignan School of Mathematics Madurai Kamaraj UniversityMaduraiTamilnaduIndia Department of Statistics Manonmaniam Sundaranar UniversityTirunelveliTamilnaduIndia

This article,we develop an optimal policy to control the service rate of a discrete time queueing-inventory system with finite *** customers arrive according to a bernoulli process and the service time for the customers are *** the buffer size attains its maximum,any arriving new customers are considered to be *** customers are served one by one according to FCFS rule and each customers request random number of *** inventory is replenished according to a(s,Q)inventory policy with geometric lead *** main objectives of this article are to determine the service rates to be employed at each slot so that the long run expected cost rate is minimized for fixed inventory level and fixed buffer size and to minimize the expected waiting time for a fixed inventory level and fixed buffer *** problems are modelled as Markov decision *** establish the existence of a stationary policy and employ linear programming method to find the optimal service *** provide some numerical examples to illustrate the behaviour of the model.

关键词： Queueing-inventory system discrete time batch demand-Markov decision process

Inflammatory Factor IL1αInduces Aberrant Astrocyte Proliferation in Spinal Cord Injury Through the Grin2c/Ca^(2+)/CaMK2b Pathway

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Neuroscience bulletin 2024年第4期40卷 421-438页

作者： Yu Xia Lu Ding Changlin Zhang Qi Xu Ming Shi Tianshun Gao Feng-Quan Zhou David Y.b.Deng Scientific Research center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China Department of Gynecology The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China Pelvic Floor Disorders center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China big Data center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China Sir Run Run Shaw Hospital Zhejiang University School of MedicineHangzhou310016China Orthopaedic and Neurological Repair center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China

Spinal cord injury(SCI)is one of the most devastating traumas,and the aberrant proliferation of astrocytes usually causes neurological ***,the mechanism underlying astrocyte over-proliferation after SCI is ***2c(glutamate ionotropic receptor type 2c)plays an essential role in cell *** bioinformatic analysis indicated that Grin2c and Ca^(2+)transport functions were inhibited in astrocytes after *** of Grin2c stimulated astrocyte proliferation by inhibiting the Ca^(2+)/calmodulin-dependent protein kinase 2b(CaMK2b)pathway in *** screening different inflammatory factors,interleukin 1α(IL1α)was further found to inhibit Grin2c/Ca^(2+)/CaMK2b and enhance astrocyte proliferation in an oxidative damage *** of IL1αusing neutralizing antibody resulted in increased Grin2c expression and the inhibition of astrocyte proliferation ***,this study suggests that IL1αpromotes astrocyte proliferation by suppressing the Grin2c/Ca^(2+)/CaMK2b pathway after SCI,revealing a novel pathological mechanism of astrocyte proliferation,and may provide potential targets for SCI repair.

关键词： IL1α Grin2c Astrocyte Spinal cord injury

增材制造Ti6Al4V合金的闪速等离子体电解氧化与在生理介质中的电化学行为

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Transactions of Nonferrous Metals Society of China 2024年第4期34卷 1150-1166页

作者： H.MORA-SANCHeZ C.RAMOS M.MOHeDANO b.TORReS R.ARRAbAL e.MATYKINA Departamento de Ingeniería Química y de Materiales Facultad de Ciencias QuímicasUniversidad Complutense de Madrid28040 MadridSpain CIDeTeC Basque Research and Technology Alliance(BRTA)Po.Miramón 19620014 Donostia-San SebastiánSpain Departamento Matemática Aplicada Ciencia e Ingeniería de Materiales y Tecnología ElectrónicaUniversidad Rey Juan CarlosC/Tulipán s/nMóstoles 28933MadridSpain

研究激光粉末床熔融增材制造(AM)(又称直接金属激光烧结)技术制备的Ti6Al4V合金等离子体电解氧化(PeO)处理及其电化学行为。通过短时间(<120 s)PeO处理(也称闪速PeO),在AM合金和传统合金表面制备了3~10μm厚、含Ca和P的涂层。然后在改... 详细信息

研究激光粉末床熔融增材制造(AM)(又称直接金属激光烧结)技术制备的Ti6Al4V合金等离子体电解氧化(PeO)处理及其电化学行为。通过短时间(eO处理(也称闪速PeO),在AM合金和传统合金表面制备了3~10μm厚、含Ca和P的涂层。然后在改良的α-MeM溶液中,通过动电位极化曲线和电化学阻抗谱(eIS)评估了合金的电化学行为。与传统合金相比,AM合金中形成了细小的层片状α显微组织和层间小尺寸的β相颗粒,这促使了火花的产生,从而促进了PeO涂层的生长。闪速PeO涂层提高了传统合金和AM合金的耐腐蚀性,最薄的涂层(eO处理也足以成功避免这种情况。

关键词：增材制造激光粉末床熔融等离子体电解氧化闪速PeO 钛缝隙腐蚀 α-MeM

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Astrophysical S-factor and reaction rate for 15N(p,γ)16O within the modified potential cluster model

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Chinese Physics C 2024年第4期48卷 130-145页

作者： S.b.Dubovichenko A.S.Tkachenko R.Ya.Kezerashvili N.A.burkova b.M.Yeleusheva Fesenkov Astrophysical Institute 050020 AlmatyKazakhstan New York City College of Technology City University of New YorkBrooklyn11201 New YorkUSA Graduate School and University center City University of New York10016 New YorkUSA al-Farabi Kazakh National University 050040 AlmatyKazakhstan

We study radiative p^(15)N capture on the ground state of ^(16)O at stellar energies within the framework of a modified potential cluster model(MPCM)with forbidden states,including low-lying *** investigation of the ^(15)N(p,γ0)^(16)O reaction includes the consideration of ^(3)S_(1) resonances due to e1 transitions and the contribution of the ^(3)P_(1) scattering wave in the p+^(15)N channel due to the ^(3)P_(1)→^(3)P_(0)M1 *** calculated the astrophysical low-energy S-factor,and the extrapolated S(0)turned out to be within 34.7−40.4 keV·*** important role of the asymptotic constant(AC)for the ^(15)N(p,γ0)16O process with interfering ^(3)S_(1)(312)and ^(3)S_(1)(962)resonances is elucidated.A comparison of our calculation for the S-factor with existing experimental and theoretical data is addressed,and a reasonable agreement is *** reaction rate is calculated and compared with the existing *** has negligible dependence on the variation of AC but shows a strong impact of the interference of ^(3)S_(1)(312)and ^(3)S_(1)(962)resonances in reference to the CNO Gamow windows,especially at low *** estimate the contribution of cascade transitions to the reaction rate based on the exclusive experimental data from ***.C.85,065810(2012).The reaction rate enhancement due to the cascade transitions is observed from T_(9)>0.3 and reaches the maximum factor~1.3 at T_(9)=*** present the Gamow energy window and a comparison of rates for radiative proton capture reactions ^(12)N(p,γ)^(13)O,^(13)N(p,γ)^(14)O,^(14)N(p,γ)^(15)O,and ^(15)N(p,γ)^(16)O obtained in the framework of the MPCM and provide the temperature windows,prevalence,and significance of each process.

关键词： low and astrophysical energies p^(15)N system thermonuclear reaction rate potential cluster model CNO-cycle

How to establish an endoscopic bariatric practice

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World Journal of Gastrointestinal endoscopy 2024年第4期16卷 178-186页

作者： Daniel b Maselli Lauren L Donnangelo brian Coan Christopher e McGowan Clinical Research True You Weight LossAtlantaGA 30342United States Clinical Research True You Weight LossCaryNC 27513United States

Obesity is a chronic,progressive,and relapsing disease of excess adiposity that contributes to more than two hundred medical conditions and is projected to affect more than half the adult population of the United States by the year *** the limited penetrance of traditional bariatric surgery,as well as the cost and adherence barriers to anti-obesity medications,there is growing interest in the rapidly evolving field of endoscopic bariatric therapies(ebTs).ebTs are minimally invasive,same-day,per-oral endoscopic procedures and include endoscopic sleeve gastroplasty,intragastric balloons,and endoscopic bariatric revisional *** field represents an exciting and innovative subspe-cialty within ***,building a successful endoscopic bariatric practice requires intentional,coordinated,and sustained efforts to overcome the numerous obstacles to *** barriers include acquisition of the technical and cognitive skillset,practice limitations including the availability of nutrition counseling,facility capabilities,direct-to-consumer marketing,and financial pressures such as facility and anesthesia *** the highest-volume center for metabolic and bariatric endoscopy in the United States,we provide insights into successfully establishing an endoscopic bariatric program.

关键词： Obesity endoscopic bariatric therapies bariatric endoscopy endoscopic sleeve gastroplasty Intragastric balloon Practice management

The rate of deadwood decomposition processes in tree stand gaps resulting from bark beetle infestation spots in mountain forests

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Forest ecosystems 2024年第3期11卷 339-346页

作者： ewa błonska Adam Gorski Jarosław Lasota Department of ecology and Silviculture Faculty of ForestryUniversity of Agriculture in Krakow29 Listopada 46 Str.31-425KrakowPoland

Decaying wood is an essential element of forest ecosystems and it affects its other *** aim of our research was to determine the decomposition rate of deadwood in various humidity and thermal conditions in the gaps formed in the montane forest *** research was carried out in the babiog orski National *** research plots were marked out in the gaps of the stands,which were formed as a result of bark beetle *** plots were located in undisturbed *** research covered wood of two species–spruce and beech in the form of cubes with dimensions of 50 mm×50 mm×22 *** samples were placed directly on the soil surface and subjected to laboratory analysis after 36 months.A significant influence of the wood species and the study plot type on the physicochemical properties of the tested wood samples was *** characteristics strongly correlated with soil moisture.A significantly higher mass decline of wood samples was recorded on the reference study plots,which were characterized by more stable moisture *** decomposition of wood in the gaps regardless of the species is related to lower *** wood species covered by the study differed in the decomposition *** wood samples were characterized by a significantly higher decomposition rate compared to beech wood *** research has confirmed that disturbances that lead to the formation of gaps have a direct impact on the decomposition process of deadwood.

关键词： bark beetle beech Decomposition rate Forest ecosystem Mass decline Spruce Woody debris

Compressive property and energy absorption characteristic of interconnected porous Mg-Zn-Y alloys with adjusting Y addition

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Journal of Magnesium and Alloys 2024年第1期12卷 171-185页

作者： J.A.Liu S.J.Liu b.Wang W.b.Sun X.J.Liu Z.W.Han College of Materials Science and engineering Key Laboratory of Automobile Materials(Ministry of Education)Jilin UniversityChangchun 130022PR China Key Laboratory of bionic engineering(Ministry of education) College of Biological and Agricultural EngineeringJilin UniversityChangchun130022PR China Weihai Institute for bionics-Jilin University Weihai 264205PR China

In this study,interconnected porous Mg-2Zn-xY alloys with different phase compositions were prepared by various Y additions(x=0.4,3,and 6 wt.%)to adjust the compressive properties and energy absorption *** characterization methods were then applied to identify the microstructure of the porous Mg-Zn-Y and describe the details of the second *** tests were performed at room temperature(RT),200℃,and 300℃to study the impact of the Y addition and testing temperature on the compressive properties of the porous *** experimental results showed that a high Y content promotes a microstructure refinement and increases the volume fraction of the second *** the Y content increases,different Mg-Zn-Y ternary phases appear:I-phase(Mg_(3)Zn_(6)Y),W-phase(Mg_(3)Zn_(3)Y_(2)),and LPSO phase(Mg_(12)ZnY).When the Y content ranges between 0.4%and 6%,the compressive strength increases from 6.30MPa to 9.23 MPa,and the energy absorption capacity increases from 7.33 MJ/m^(3)to 10.97 MJ/m^(3)at RT,which is mainly attributed to the phase composition and volume fraction of the second ***,the average energy absorption efficiency is independent of the Y *** addition,the compressive deformation behaviors of the porous Mg-Zn-Y are altered by the testing *** compressive strength and energy absorption capacity of the porous Mg-Zn-Y decrease due to the softening effect of the high temperature on the *** deformation behaviors at different temperatures are finally observed to reflect the failure mechanisms of the struts.

关键词： Porous magnesium Rare earth elements Microstructure Compressive behavior energy absorption characteristic