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Hierarchical control Strategy for Load Regulation Based on Stackelberg Game Theory considering Randomness

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cSee Journal of Power and energy Systems 2024年第3期10卷 929-941页

作者： Tingyu Jiang Ping Ju c.Y.chung Yuzhong Gong college of energy and electrical engineering Hohai UniversityNanjing 211100China Department of electrical engineering City University of Hong KongHong Kong CF624China Department of electrical and computer engineering University of SaskatchewanSaskatoonSK S7N 5A9Canada cSee Ieee

Demand response has been recognized as a valuable functionality of power systems for mitigating power *** paper proposes a hierarchical control strategy among the distribution system operator(DSO),load aggregators(LAs),and thermostatically controlled loads(TcLs);the strategy includes a scheduling layer and an executive layer to provide load *** the scheduling layer,the DSO(leader)offers compensation price(cP)strategies,and the LAs(followers)respond to cP strategies with available regulation power(ARP)*** of the DSO and LAs are modeled according to their behaviors during the load regulation *** game is adopted to capture interactions among the players and leader and to obtain the optimal strategy for each participant to achieve ***,considering inevitable random factors in practice,e.g.,renewable generation and behavior of users,two different stochastic models based on sample average approximation(SAA)and parameter modification are formulated with improved scheduling *** the executive layer,distributed TcLs are triggered based on strategies determined in the scheduling layer.A self-triggering method that does not violate user privacy is presented,where TcLs receive external signals from the LA and independently determine whether to alter their operation *** simulations are performed on the modified Ieee-24 bus system to verify effectiveness of the proposed strategy.

关键词： Demand response hierarchical control load regulation self-triggering method Stackelberg game

Data-driven Static equivalence with Physics-informed Koopman Operators

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cSee Journal of Power and energy Systems 2024年第1期10卷 432-438页

作者： Wei Lin changhong Zhao Maosheng Gao c.Y.chung Department of electrical engineering The Hong Kong Polytechnic UniversityHong Kong SARChina Department of Information engineering The Chinese University of Hong KongHong Kong SARChina School of electrical engineering Chongqing UniversityChongqing 400044China

With deployment of measurement units,fitting static equivalent models of distribution networks(DNs)by linear regression has been recognized as an effective method in power flow analysis of a transmission *** volatility of measurements caused by variable distributed renewable energy sources makes it more difficult to accurately fit such equivalent *** tackle this challenge,this letter proposes a novel data-driven method to improve equivalency accuracy of DNs with distributed energy *** letter provides a new perspective that an equivalent model can be regarded as a mapping from internal conditions and border voltages to border power *** mapping can be established through 1)Koopman operator theory,and 2)physical features of power flow equations at the root node of a *** of the proposed method is demonstrated on the Ieee 33-bus and Ieee 136-bus test systems connected to a 661-bus utility system.

关键词： Data-driven distribution network Koopman operator theory static equivalent model

Burden of gallstone disease in the United States population:Prepandemic rates and trends

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World Journal of Gastrointestinal Surgery 2024年第4期16卷 1130-1148页

作者： Aynur Unalp-Arida constance e Ruhl National Institute of Diabetes and Digestive and Kidney Diseases National Institutes of HealthBethesdaMD 20892-5458United States Social&Scientific Systems Inc.DLH Holdings Corp CompanySilver SpringMD 20910United States

BAcKGROUND Gallstone disease is one of the most common digestive disorders in the United States and leads to significant morbidity,mortality,and health care *** To expand on earlier findings and investigate prepandemic rates and trends in the gallstone disease burden in the United States using national survey and claims *** The National Ambulatory Medical care Survey,National Inpatient Sample,Nationwide emergency Department Sample,Nationwide Ambulatory Surgery Sample,Vital Statistics of the United States,Optum clinformatics®Data Mart,and centers for Medicare and Medicaid Services Medicare 5%Sample and Medicaid files were used to estimate claims-based prevalence,medical care including cholecystectomy,and mortality with a primary or other gallstone *** were age-adjusted(for national databases)and shown per 100000 *** Gallstone disease prevalence(claims-based,2019)was 0.70%among commercial insurance enrollees,1.03%among Medicaid beneficiaries,and 2.09%among Medicare beneficiaries and rose over the previous ***,in the United States population,gallstone disease contributed to approximately 2.2 million ambulatory care visits,1.2 million emergency department visits,625000 hospital discharges,and 2000 deaths *** had higher medical care rates with a gallstone disease diagnosis,but mortality rates were higher among *** had higher ambulatory care visit and hospital discharge rates compared with Whites,but not mortality *** had lower ambulatory care visit and mortality rates,but similar hospital discharge rates compared with *** the study period,ambulatory care and emergency department visit rates with a gallstone disease diagnosis rose,while hospital discharge and mortality rates *** commercial insurance enrollees,rates were higher compared with national data for ambulatory care visits and hospitalizations,but lower for emergency department ***

关键词： Gallstone disease Burden cholecystectomy Mortality Health care use cholelithiasis Gallstones epidemiology

Near resonance vibration isolation on a levered-dual response(LeDAR)coulomb-damped system by differential preloads/offsets in linear springs

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Applied Mathematics and Mechanics(english edition) 2024年第6期45卷 1033-1050页

作者： T.I.TOLUWALOJU c.K.THeIN D.HALIM Department of Mechanical Materials and Manufacturing EngineeringUniversity of Nottingham Ningbo ChinaNingbo 315100Zhejiang ProvinceChina Nottingham Ningbo china Beacons of excellence Research and Innovation Institute University of Nottingham Ningbo ChinaNingbo 315048Zhejiang ProvinceChina

The levered-dual response(LeDAR)coulomb-damped system attains near resonant vibration isolation by differential preloads/offsets in linear *** takes the advantages of both the preloads/offsets in linear springs and the guiderail friction for realizing different levels of vibration *** isolation capacities are investigated on the strategies with both the horizontal and vertical guiderails,with the horizontal rail only,and without *** compressive preloads generally result in the consumption of most of the initial excitation energy so as to overcome the potential *** isolation onsets at the frequency ratio of 1∓0.095 on the left-hand side(LHS)and the right-hand side(RHS)of the lever are relative to the load plate *** observed near resonant isolation thus makes the LeDAR system a candidate for the isolation of the mechanical systems about resonance while opening a path for simultaneous harvesterisolation functions and passive functions at extreme frequencies.

关键词： lever ratio coulomb damping preload tension/compression isolation band/depth offset potential

Influence of Methane-Hydrogen Mixture characteristics on compressor Vibrations

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Fluid Dynamics & Materials Processing 2024年第5期20卷 1031-1043页

作者： Vladimir Ya.Modorskii Ivan e.cherepanov High Performance computing center Perm National Research Polytechnic UniversityPerm614990Russia

A transition to clean hydrogen energy will not be possible until the issues related to its production, transportation,storage, etc., are adequately resolved. currently, however, it is possible to use methane-hydrogen *** gas can be transported using a pipeline system with the required pressure being maintained by gascompression stations. This method, however, is affected by some problems too. compressors emergency stopscan be induced by vibrations because in some cases, mechanical methods are not able to reduce the vibrationamplitude. As an example, it is known that a gas-dynamic flow effect in labyrinth seals can lead to increasedvibrations. This paper presents the numerical simulation of rotor oscillations taking into account a gas-dynamicload. The influence of a transported mixture on the oscillatory process is investigated. Mixtures consisting ofmethane and hydrogen in various proportions and an air mixture are considered. The results are discussed forvarious operating pressures and include the rotor motion trajectories and oscillation frequency spectra obtainednumerically. It is shown that the gas mixture composition has a significant effect on the oscillations and theiroccurrence. Hydrogen as a working fluid reduces the vibration amplitude. Operating a compressor with hydrogenleads to a decrease in the resonant frequency, bringing it closer to the operating one. However, the operatingpressure at which maximum oscillations are observed depends slightly on the gas mixture composition.

关键词： Seal stabilities vibration FSI cFD multiphase flows hydrogen

Scanning transmission electron microscopy and atom probe tomography analysis of non-stoichiometry long-period-stacking-ordered structures in Mg-Ni-Y/Sm alloys

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Journal of Magnesium and Alloys 2024年第3期12卷 954-965页

作者： Yimeng chen Manuel Legrée Jean-Louis Bobet Alexander Kvit cAMecA Instruments Inc MadisonWI 53711USA IcMcB Universitéde BordeauxPessacCEDEX 33608France NIAc&Materials Science Department University of WisconsinMadisonWI 53706USA

The long-period-stacking-ordered(LPSO)structure affects the mechanical,corrosion and hydrolysis properties of Mg *** current work employs high angle annular dark field-scanning transmission electron microscopy(HAADF-STeM)and atom probe tomography(APT)to investigate the structural and local chemical information of LPSO phases formed in Mg-Ni-Y/Sm ternary alloys after extended isothermal *** on the alloying elements and their concentrations,Mg-Ni-Y/Sm develops a two-phase LPSO+α-Mg structure in which the LPSO phase contains defects,hybrid LPSO structure,and Mg ***-STeM and APT indicate non-stoichiometric LPSO with incomplete Ni_(6)(Y/Sm)_(8) *** addition,the APT quantitatively determines the local composition of LPSO and confirms the presence of Ni within the Mg bonding *** results provide insight into a better understanding of the structure and hydrolysis properties of LPSO-Mg alloys.

关键词： Magnesium alloys Long-range ordering Atom probe tomography(APT) STeM HAADF Hydrolysis properties.

could mammalian inorganic polyphosphate be a crucial signaling molecule in neurological disorders?

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Neural Regeneration Research 2024年第4期19卷 701-702页

作者： Renata Torres Da costa Maria e.Solesio Rutgers University Department of BiologyCamdenNJUSA

Since the early stages of life on earth,cellular metabolism has evolved to adapt to fluctuations in nutrient and oxygen *** this context,mammals,which are probably the organisms that show one of the highest levels of metabolic complexity,have developed an elegant system that uses constant and rechargeable energy sources of modulate their *** homeostasis is especially important in the central nervous system,as neurons and other cells in the brain are highly susceptible to fluctuations in nutrients and oxygen availability.

关键词： metabolism homeostasis neurological

Juvenile survival curves in a solitary ground squirrel with a prolonged hibernation:effects of individual characteristics,environment,and maternal investment

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current Zoology 2024年第1期70卷 13-23页

作者： Nina A.Vasilieva Liudmila e Savinetskaya Andrey V.Tchabovsky A.N.Severtsov Institute of ecology and evolution Russian Academy of SciencesMoscow 119071Russia

Juvenile survival is a key life-history influence on population dynamics and adaptive *** analyzed the effects of individual chara-cteristics,early environment,and maternal investment on juvenile survival in a large solitary hibernating rodent-yellow ground squirrel Spermophilus fulvus using cox mixed-effects *** 48%of weaned pups survived to dispersal and 17%survived to *** life expectancy was primarily determined by individual characteristics and,to a lesser extent,by the early *** strongest and pos-itive predictor of juvenile survival was body mass which crucially affected mortality immediately after *** suffered higher mortality than females after the onset of dispersal;however,the overall difference between sexes was partly masked by high rates of mortality in the first days after emergence in both *** emerged juveniles had lower life expectancy than the earliest *** overall effect of local juvenile density was *** lactation did not enhance juvenile survival:Pups nursed longer survived shorter than the young nursed for a shorter *** findings support the hypothesis that females of *** cannot effectively regulate maternal expenditures to mitigate the effects of unfavorable conditions on their *** strategy to deal with seasonal time constraints on life history in female *** suggests an early termination of maternal care at the cost of juvenile quality and *** female reproductive strategy corresponds to a"fast-solitary"life of folivorous desert-dwelling *** and other solitary ground squirrels with prolonged hibernation.

关键词： early-life conditions ground squirrels hibernation juvenile mortality maternal investment survival curves

commentary on “Does light-intensity physical activity moderate the relationship between sitting time and adiposity markers in adolescents?”

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Journal of Sport and Health Science 2024年第4期13卷 453-454页

作者： Barbara e.Ainsworth Amanda M.Ferland School of exercise and Health Shanghai University of SportShanghai 200433China Department of Orthopedics Tongji UniversityShanghai 200092China

In the September 2022 issue of the Journal of Sport and Health Science,Ayala et al.1 published results from a cross-sectional study where they tested the hypothesis that light intensity physical activity(LIPA,1.6-2.9 metabolic equivalents(MeTs))moderates the relationship between sitting time and adiposity in 219 Australian adolescents aged 14±1.6 years(mean±SD).

关键词： metabolic light