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Experimental studies on impedance based fault location for long transmission lines

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Protection and Control of Modern Power systems 2017年第1期2卷 169-177页

作者： saeed Roostaee mini s.thomas shabana Mehfuz Department of Electrical Engineering Faculty of Engineering and TechnologyJamia Millia IslamiaNew DelhiIndia

In long transmission lines,the charging current caused by the shunt capacitance decreases the accuracy in impedance based fault *** improve the accuracy of fault location,this paper presents a novel scheme,where two Digital Fault Recorders(DFRs)are installed in a *** can send the transient data of the faults to the both ends of a *** estimate the distance of a fault,impedance based fault location methods are applied with transient fault data of both ends protection relays and both DFRs installed in a *** evaluate the proposed scheme,a laboratory setup has been *** the lab,several faults have been simulated and associated voltages and currents are injected to a relay IED to compare experimental results.

关键词： Transmission line fault location Impedance based fault location

Paraneoplastic retinopathies: an update on pathogenesis, diagnosis and management

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Annals of Eye science 2024年第1期9卷 34-42页

作者： Akshay s.thomas Tennessee Retina NashvilleTNUSA

The paraneoplastic retinopathies are a heterogeneous group of disorders with significant visual consequences occuring in the setting of a systemic *** conditions may be characterized by the presence of antiretinal antibodies and may predate or follow the diagnosis of an underlying *** I review the clinical findings,pathophysiology,laboratory testing and management of the paraneoplastic retinopathies:cancer-associated retinopathy(CAR),melanoma-associated retinopathy(MAR),bilateral diffuse uveal melanocytic proliferation(BDUMP)and paraneoplastic vitelliform maculopathy(PVM).The pathophysiology of the paraneoplastic retinopathies varies from molecular mimicry resulting in anti-retinal antibody production(CAR,MAR)to relases of soluble factors either by the primary tumor(BDUMP)and/or immune system in response to the primary tumor(PVM)which result in retinal and/or retinal pigment epithelium *** each condition,structural and functional multimodal retinal testing can be helpful in establishing the *** for the paraneoplastic retinopathies involves a combination of treating the underlying malignancy plus additional local and/or systemic immunosuppressive agents though no systemic therapeutic protocols *** these interventions,the retinopathy may be progressive or the retinopathy may be a harbinger of poor ***,prompt diagnosis may help identify an underlying malignancy earlier and may thus improve cancer-related survival.

关键词： Paraneoplastic retinopathy bilateral diffuse uveal melanocytic proliferation(BDUMP) cancer-associated retinopathy(CAR) vitelliform

Piezoelectric resonant ice protection systems-Part 2/2:Evaluation of benefits at aircraft level

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Chinese Journal of Aeronautics 2024年第6期37卷 50-63页

作者： Valerian PALANQUE thomas PLANEs Pommier-Budinger VALERIE Budinger MARC Delbecq sCOTT Institut Clement Ader(ICA) INSAISAE-SUPAEROMINES ALBIUPSCNRSUniversity of Toulouse31400 ToulouseFrance Federation ENAC IsAE-sUPAERO ONERA University of Toulouse31400 ToulouseFrance

Piezoelectric resonant de-icing systems are attracting great *** paper aims to assess the implementation of these systems at the aircraft *** article begins with the model to compute the power requirement of a piezoelectric resonant de-icing system sized from the prototype detailed in Part 1/2 of this *** the mass,drag,and fuel consumption of this system and the subcomponents needed for its implementation are *** features of a piezoelectric resonant de-icing system are finally computed for aircraft similar to Airbus A320 aircraft and aircraft of different categories(Boeing 787,ATR 72 and TBM 900)and compared with the existing thermal and mechanical ice protection systems.A sensitivity analysis of the main key sizing parameters of the piezoelectric de-icing system is also performed to identify the main axes of improvement for this *** study shows the potential of such ice protection *** particular,for the realistic input parameters chosen in this work,the electro-mechanical solution can provide a 54% reduction in terms of mass and a 92% reduction in terms of power consumption for an A320 aircraft architecture,leading to a 74% decrease in the associated fuel consumption compared to the actual air bleed system.

关键词： Ice protection system De-icing Piezoelectric Electro-mechanical system Power Fuel consumption

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Insights into carbon dioxide sequestration into coal seams through coupled gas flow-adsorption-deformation modelling

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 26-40页

作者： Hywel thomas Min Chen Geoenvironmental Research Centre Cardiff School of EngineeringCardiff UniversityQueen’s BuildingsThe ParadeNewport RoadCardiffCF243AAUK Key Laboratory of Marine Geology Tongji UniversityShanghai200092China

Injecting carbon dioxide(CO_(2))into coal seams may unlock substantial carbon sequestration *** the coal acts like a carbon filter,it can preferentially absorb significant amounts of CO_(2).To explore this further,desorption of the adsorbed gas due to pressure drop is investigated in this paper,to achieve an improved understanding of the long-term fate of injected CO_(2) during post-injection *** paper presents a dual porosity model coupling gas flow,adsorption and geomechanics for studying coupled processes and effectiveness of CO_(2) sequestration in coals.A new adsorption?desorption model derived based on thermodynamics is incorporated,particularly,the desorption hysteresis is *** reliability of the proposed adsorption-desorption isotherm is examined via validation *** is indicated that occurrence of desorption hysteresis is attributed to the adsorption-induced pore *** injection ceases,the injected gas continues to propagate further from the injection well,while the pressure in the vicinity of the injection well experiences a significant *** the adsorbed gas near the well also decreases,this decrease is less compared to that in pressure because of desorption *** unceasing spread of CO_(2) and drops of pressure and adsorbed gas depend on the degree of desorption hysteresis and heterogeneity of coals,which should be considered when designing CO_(2) sequestration into coal seams.

关键词： CO_(2)geological storage Coal seam Adsorption Desorption hysteresis

CLAssIFICATIONs OF DUPIN HYPERsURFACEs IN LIE sPHERE GEOMETRY

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Acta Mathematica scientia 2024年第1期44卷 1-36页

作者： thomas E.CECIL Department of Mathematics and Computer science College of the Holy CrossWorcesterMA01610USA

This is a survey of local and global classification results concerning Dupin hypersurfaces in s^(n)(or R^(n))that have been obtained in the context of Lie sphere *** emphasis is on results that relate Dupin hypersurfaces to isoparametric hypersurfaces in *** with these classification results,many important concepts from Lie sphere geometry,such as curvature spheres,Lie curvatures,and Legendre lifts of submanifolds of s^(n)(or R^(n)),are described in *** paper also contains several important constructions of Dupin hypersurfaces with certain special properties.

关键词： Dupin hypersurfaces isoparametric hypersurfaces Lie sphere geometry Lie sphere transformations Lie curvatures

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How to enhance agricultural plastic waste management in China?Insights from public participation

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Journal of Integrative Agriculture 2024年第6期23卷 2127-2143页

作者： Aibo Hao thomas Dogot Changbin Yin state Key Laboratory of Efficient Utilization of Arid and semi-arid Arable Land in Northern China Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China Economics and Rural Development Laboratory TERRA Teaching and Research CentreGembloux Agro-Bio TechUniversity of LiègeGembloux B-5030Belgium Research Center for Agricultural Green Development in China Beijing 100081China

Agricultural plastics play a pivotal role in agricultural ***,due to expensive costs,agricultural plastic waste management(APWM)encounters a vast funding *** one of the crucial stakeholders,the public deserves to make appropriate efforts for ***,identifying whether the public is willing to pay for APWM and clarifying the decisions’driving pathways to explore initiatives for promoting their payment intentions are essential to address the dilemma confronting *** this end,by applying the extended theory of planned behavior(TPB),the study conducted an empirical analysis based on 1,288 residents from four provinces(autonomous regions)of northern *** illustrate that:1)respondents hold generally positive and relatively strong payment willingness towards APWM;2)respondents’attitude(AT),subjective norm(sN),and perceived behavioral control(PBC)are positively correlated with their payment intentions(INT);3)environmental cognition(EC)and environmental emotion(EE)positively moderate the relationships between AT and INT,and between sN and INT,posing significant indirect impacts on *** study’s implications extend to informing government policies,suggesting that multi-entity cooperation,specifically public payment for APWM,can enhance agricultural non-point waste management.

关键词： agricultural plastic waste extended theory of planned behavior public payment environmental cognition environmental emotion

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Theory and classification of mass extinction causation

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National science Review 2024年第1期11卷 16-36页

作者： thomas J.Algeo Jun shen state Key Laboratory of Biogeology and Environmental Geology China University of Geosciences—Wuhan state Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences—Wuhan Department of Geosciences University of Cincinnati

Theory regarding the causation of mass extinctions is in need of systematization, which is the focus of this contribution. Every mass extinction has both an ultimate cause, i.e. the trigger that leads to various climato-environmental changes, and one or more proximate cause(s), i.e. the specific climato-environmental changes that result in elevated biotic mortality. With regard to ultimate causes, strong cases can be made that bolide(i.e. meteor) impacts, large igneous province(LIP) eruptions and bioevolutionary events have each triggered one or more of the Phanerozoic Big Five mass extinctions, and that tectono-oceanic changes have triggered some second-order extinction events. Apart from bolide impacts, other astronomical triggers(*** flares, gamma bursts and supernova explosions) remain entirely in the realm of speculation. With regard to proximate mechanisms, most extinctions are related to either carbon-release or carbon-burial processes, the former being associated with climatic warming, ocean acidification, reduced marine productivity and lower carbonate δ13C values, and the latter with climatic cooling, increased marine productivity and higher carbonate δ13C values. Environmental parameters such as marine redox conditions and terrestrial weathering intensity do not show consistent relationships with carbon-cycle *** this context, mass extinction causation can be usefully classified using a matrix of ultimate and proximate factors. Among the Big Five mass extinctions, the end-Cretaceous biocrisis is an example of a bolide-triggered carbon-release event, the end-Permian and end-Triassic biocrises are examples of LIP-triggered carbon-release events, and the Late Ordovician and Late Devonian biocrises are examples of bioevolution-triggered carbon-burial events. Whereas the bolide-impact and LIP-eruption mechanisms appear to invariably cause carbon release, bioevolutionary triggers can result in variable carbon-cycle changes, e.g. carbon burial durin

关键词： biocrisis ultimate cause proximate cause bolide large igneous province bioevolutionary event

Dynamic convergent shock compression initiated by return current in high-intensity laser-solid interactions

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Matter and Radiation at Extremes 2024年第4期9卷 40-53页

作者： Long Yang Martin Rehwald thomas Kluge Alejandro LasoGarcia Toma Toncian Karl Zeil Ulrich schramm thomas E.Cowan Lingen Huang Helmholtz-Zentrum Dresden-Rossendorf 01328 DresdenGermany Technische Universitat Dresden 01062 DresdenGermany

We investigate the dynamics of convergent shock compression in solid cylindrical targets irradiated by an ultrafast relativistic laser *** particle-in-cell simulations and coupled hydrodynamic simulations reveal that the compression process is initiated by both magnetic pressure and surface ablation associated with a strong transient surface return current with density of the order of 10^(17) A/m^(2) and lifetime of 100 *** results show that the dominant compression mechanism is governed by the plasma β,i.e.,the ratio of thermal pressure to magnetic *** targets with small radius and low atomic number Z,the magnetic pressure is the dominant shock compression *** to a scaling law,as the target radius and Z increase,the surface ablation pressure becomes the main mechanism generating convergent ***,an indirect experimental indication of shocked hydrogen compression is provided by optical shadowgraphy measurements of the evolution of the plasma expansion *** results presented here provide a novel basis for the generation of extremely high pressures exceeding Gbar(100 TPa)to enable the investigation of high-pressure physics using femtosecond J-level laser pulses,offering an alternative to nanosecond kJ-laser pulse-driven and pulsed power Z-pinch compression methods.

关键词： shock convergent return

Development of gradient boosting-assisted machine learning data-driven model for free chlorine residual prediction

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Frontiers of Environmental science & Engineering 2024年第2期18卷 35-46页

作者： Wiley Helm shifa Zhong Elliot Reid thomas Igou Yongsheng Chen school of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA 30332USA school of Ecological and Environmental sciences East China Normal UniversityShanghai 200241China

Chlorine-based disinfection is ubiquitous in conventional drinking water treatment (DWT) and serves to mitigate threats of acute microbial disease caused by pathogens that may be present in source water. An important index of disinfection efficiency is the free chlorine residual (FCR), a regulated disinfection parameter in the Us that indirectly measures disinfectant power for prevention of microbial recontamination during DWT and distribution. This work demonstrates how machine learning (ML) can be implemented to improve FCR forecasting when supplied with water quality data from a real, full-scale chlorine disinfection system in Georgia, UsA. More precisely, a gradient-boosting ML method (CatBoost) was developed from a full year of DWT plant-generated chlorine disinfection data, including water quality parameters (e.g., temperature, turbidity, pH) and operational process data (e.g., flowrates), to predict FCR. Four gradient-boosting models were implemented, with the highest performance achieving a coefficient of determination, R2, of 0.937. Values that provide explanations using shapley’s additive method were used to interpret the model’s results, uncovering that standard DWT operating parameters, although non-intuitive and theoretically non-causal, vastly improved prediction performance. These results provide a base case for data-driven DWT disinfection supervision and suggest process monitoring methods to provide better information to plant operators for implementation of safe chlorine dosing to maintain optimum FCR.

关键词： Machine learning Data-driven modeling Drinking water treatment Disinfection Chlorination