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Not just fuel: energy stores are correlated with immune function and oxidative damage in a long-distance migrant

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Current Zoology 2020年第1期66卷 21-28页

作者： Cas EIKENAAR arne HEGEMANN Florian PACKMOR Iris KLEUDGEN Caroline ISAKSSON Institute of Avian Research 26386 WilhelmshavenGermany Department of Biology Lund UniversityLundSE-22362Sweden School of Natural Sciences Bangor UniversityDeiniol RoadBangorLL572DGUK

In many animals,catabolic and anabolic periods are temporally *** birds alternate energy expenditure during flight with energy accumulation during *** size of the energy stores at stopover affects the decision to resume migration and thus the temporal organization of *** now provide data suggesting that it is not only the size of the energy stores per se that may influence migration scheduling,but also the physiological consequences of *** two subspecies of the northern wheatear Oenanthe oenanthe,a long-distance migrant,estimated energy stores at a stopover during autumn migration were positively related with both constitutive innate and acquired immune function,and negatively related with oxidative damage to *** other words,migrants'physiological condition was associated with their energetic *** time spent at stopover before sampling may have contributed to this relationship,our results suggest that migrants have to trade-off the depletion of energy stores during flight with incurring physiological *** will affect migrants'decisions when to start and when to terminate a migratory *** physiological costs associated with the depletion of energy stores may also help explaining why migrants often arrive at and depart from stopover sites with larger energy stores than *** propose that studies on the role of energy stores as drivers of the temporal organization of(avian)migration need to consider physiological condition,such as immunological and oxidative states.

关键词： migration oxidative stress eco-immunology immunity fat stores physiology

DISastER INFORMATION THROUGHOUT NATION

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Natural Disaster Reduction in China 1996年第3期 97-102页

作者： (up to July 18)

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Applying Synchronous Condenser for Damping Provision in Converter-dominated Power System

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Journal of Modern Power Systems and Clean Energy 2021年第3期9卷 639-647页

作者： Ha Thi Nguyen Guangya Yang arne Hejde Nielsen Peter HΦjgaard Jensen Bikash Pal the Department of Electrical Engineering Danmarks Tekniske UniversitetRoskildeDenmark the Electrical Engineering Technical University of DenmarkLyngbyDenmark Siemens AG Sektor Energie BallerupDenmark the Department of Electrical and Electronic Engineering Imperial College LondonLondonUK

The dynamic characteristics of converter-dominated systems are governed by controlling power converters and the interactions between converter systems and conventional *** oscillations can appear under dynamic operation conditions caused by the phase-locked loop dynamics and interactions among the converter control *** oscillations may be poorly damped,which can result in reduced power generation,longer settling time,or disconnections of sensitive *** is foreseeable that damping services will be critical for power grid stabilization in the future with high penetration of renewable *** this work,synchronous condensers(SCs)are evaluated and applied to provide damping services to the power grid under post-event *** innovative supplementary controller for the automatic voltage regulator of SCs is proposed to improve the frequency stabilization in a converter-dominated system after *** local and remote measurements,SCs are able to modulate the reactive power output and hence,the terminal bus voltage,which further impacts the power flow in the system;therefore,damping can be provided to the frequency *** control is implemented on an industrial-level hardware platform,and the performance is verified by the hardware-in-the-loop simulation.

关键词： Power oscillation Prony analysis low-inertia system supplementary controller synchronous condenser(SC)

Existence of Weak Solutions for the Cahn-Hilliard Reaction Model Including Elastic Effects and Damage

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Journal of Partial Differential Equations 2017年第2期30卷 111-145页

作者： KRAUS Christiane ROGGENSACK arne Weierstrass Institute Mohrenstr. 39 10117 Berlin Germany.

In this paper, we introduce and study analytically a vectorial Cahn-Hilliard reaction model coupled with rate-dependent damage processes. The recently proposed Cahn-Hilliard reaction model can e.g. be used to describe the behavior of electrodes of lithium-ion batteries as it includes both the intercalation reactions at the surfaces and the separation into different phases. The coupling with the damage process allows considering simultaneously the evolution of a damage field, a second important physical effect occurring during the charging or discharging of batteries. Mathematically, this is realized by a Cahn-Larch system with a non-linear Newton boundary condition for the chemical potential and a doubly non-linear differential inclusion for the damage evolution. We show that this system possesses an underlying generalized gradient structure which incorporates the non-linear Newton boundary condition. Using this gradient structure and techniques from the field of convex analysis we are able to prove constructively the existence of weak solutions.

关键词： Cahn-Hilliard reaction system rate-dependent damage phase separation existence non-linear Newton boundary condition.

Design and compensation of second-order sub-sampling digital frontend

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Journal of Central South University 2012年第2期19卷 408-416页

作者：王洪梅 KIM Jae-hyung LEE Sang-hyuk KIM Hyung-jung KIM Jin-up KOH Jong-seog School of Mechatronics Changwon National University Electrical and Electronic Engineering Xi'an Jiaotong-Liverpool University Smart Radio Team Electonics and Telecommunication Research Institute Korea Telecommunication Company

The problem of designing a digital frontend (DFE) was considered which can dynamically access or sense dual bands in any radio frequency (RF) regions without requiring hardware changes. In particular, second-order bandpass sampling (BPS) as a technique that enables to realize the multiband reception function was discussed. In a second-order BPS system, digital reconstruction filters were utilized to eliminate the interferences generated while down converting arbitrarily positioned RF-band signals by using the direct digitization method. However, the inaccuracy in the phase shift or the amplitude mismatch between the two sample streams may cause insufficient rejection of interference. Practical problems were studied, such as performance degradation in signal-to-interference ratio (SIR) and compensation methods to overcome them. In order to demonstrate the second- order BPS as a flexible DFE suitable for software-defined radio (SDR) or cognitive radio (CR), a DFE testbed with a reconfigurable structure was implemented. Moreover, with a view to further demonstrate the proposed compensation algorithms, experimental results show that dual bands are received simultaneously.

关键词： bandpass sampling second order band-pass sampling reconfiguration software-defined radio

A review on the performance of conventional and energy-absorbing rockbolts

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Journal of Rock Mechanics and Geotechnical Engineering 2014年第4期6卷 315-327页

作者： Charlie C.Li Gisle Stjern arne Myrvang Department of Geology and Mineral Resources Engineering Norwegian University of Science and Technology (NTNU) Trondheim 7491 Norway Statoil ASA Stavanger Norway

This is a review paper on the performances of both conventional and energy-absorbing rockbolts manifested in laboratory tests. Characteristic parameters such as ultimate load, displacement and energy absorption are reported, in addition to load-displacement graphs for every type of rockbolt. Conventional rockbolts refer to mechanical rockbolts, fully-grouted rebars and frictional rockbolts. According to the test results, under static pull loading a mechanical rockbolt usually fails at the plate; a fully-grouted rebar bolt fails in the bolt shank at an ultimate load equal to the strength of the steel after a small amount of displacement; and a frictional rockbolt is subjected to large displacement at a low yield load. Under shear loading, all types of bolts fail in the shank. Energy-absorbing rockbolts are developed aiming to combat instability problems in burst-prone and squeezing rock conditions. They absorb deformation energy either through ploughing/slippage at predefined load levels or through stretching of the steel bolt. An energy-absorbing rockbolt can carry a high load and also accommodate significant rock displacement, and thus its energy-absorbing capacity is high. The test results show that the energy absorption of the energy-absorbing bolts is much larger than that of all conventional bolts. The dynamic load capacity is smaller than the static load capacity for the energy-absorbing bolts displacing based on ploughing/slippage while they are approximately the same for the D-Bolt that displaces based on steel stretching.

关键词： Rockbolt Laboratory bolt testEnergy-absorbing rockbolt Yield rockbolt Pull testShear test Dynamic testDrop test

A RESTful proxy and data model for linked sensor data

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International Journal of Digital Earth 2013年第3期6卷 233-254页

作者： Krzysztof Janowicz arne Broring Christoph Stasch Sven Schade Thomas Everding Alejandro Llaves Department of Geography University of CaliforniaSanta BarbaraCAUSA North Initiative for Geospatial Open Source Software MunsterGermany Faculty ITC University of TwenteEnschedeTheNetherlands Institute for Geoinformatics University of MunsterMunsterGermany Joint Research Centre Institute for Environment and SustainabilityIspraItaly

The vision of a Digital Earth calls for more dynamic information systems,new sources of information,and stronger capabilities for their *** networks have been identified as a major information source for the Digital Earth,while Semantic Web technologies have been proposed to facilitate *** far,sensor data are stored and published using the Observations&Measurements standard of the Open Geospatial Consortium(OGC)as data *** the advent of Volunteered Geographic Information and the Semantic Sensor Web,work on an ontological model gained importance within Sensor Web Enablement(SWE).In contrast to data models,an ontological approach abstracts from implementation details by focusing on modeling the physical world from the perspective of a particular *** restrict the interpretation of vocabularies toward their intended *** ongoing paradigm shift to Linked Sensor Data complements this *** questions have to be addressed:(1)how to refer to changing and frequently updated data sets using Uniform Resource Identifiers,and(2)how to establish meaningful links between those data sets,that is,observations,sensors,features of interest,and observed properties?In this paper,we present a Linked Data model and a RESTful proxy for OGC’s Sensor Observation Service to improve integration and inter-linkage of observation data for the Digital Earth.

关键词： Digital Earth geospatial data integration spatial data infrastructure earth observation data exchange models linked data semantic enablement

A Survey of the Use of the Discrete-event Simulation in Manufacturing Industry

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厦门大学学报（自然科学版） 2002年第S1期41卷 193-195页

作者： arne Ingemansson Gunnar S Bolmsj Ulrika Harlin Department of Mechanical Engineering Lund UniversityDepartment of Mechanical Engineering Lund UniversityIVF Industrial Research and Development Corporation Mlndal SwedenSwedenSweden

In this work, a survey of companies has been produc ed from a questionnaire and in-depth inter-views. The aimof the paper is to give a current view of the use of DES (Discrete- Event Simulation) in the indust ry. The companies have been selected in a wide range in e.g. size, capital turno ver and employees. The survey was restricted to Sweden, although the results may be applicable to other countries with similar industrial structure. Some of the companies investigated are also multinational with branches around the world. T o illustrate the differences in production systems different sectors have be en investigated, e.g. the manufacturing industry and energy sector. The manufact uring systems generally differ in that the energy sector is more known for high reliability in their systems and the manufacturing sector tends to work more wit h lean production. Previous surveys of manufacturing efficiency illustrate different aspects. Accor ding to one survey, more than one-third (34%) of the disturbances in two countr ies (the U.S. and Finland) were mainly caused by design-based errors and flaws. The survey also showed the scope of safety problems experienced in the implemen tation and use of flexible manufacturing systems (Jrvinen et al., 1996). Another survey in Germany reports a gap between users and non-users of DES. Man y companies that are not familiar with simulation are not aware of its benefits. The study suggested integrating simulation into the planning processes as a reg ular tool. So far, DES is mostly used in system planning, resource planning and scheduling and production planning (Hirschberg & Heitmann, 1997). The disposition of the accomplished questionnaire had been multiple-choice ques tions in a strict order. The respondents gave their views on what the interviewe r considered relevant for the survey. The questionnaire was mailed to 220 person s in May 2001; a second round for unanswered surveys was dispatched in August 20 01. Replies came from 114 r

关键词： discrete-event simulation manufacturing systems disturbances productivity improvement

On Pattern Selection in Three-Dimensional Benard-Marangoni Flows

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Communications in Computational Physics 2012年第3期11卷 893-924页

作者： arne Morten Kvarving Tormod Bjøntegaard Einar M.Rønquist Department of Mathematical Sciences Norwegian University of Science and Technology(NTNU)Norway

In this paper we study B´enard-Marangoni convection in confined containers where a thin fluid layer is heated from *** consider containers with circular,square and hexagonal *** Marangoni numbers close to the critical Marangoni number,the flow patterns are dominated by the appearance of the wellknown hexagonal convection *** main purpose of this computational study is to explore the possible patterns the systemmay end up in for a given set of *** a series of numerical experiments,the coupled fluid-thermal system is started with a zero initial condition for the velocity and a random initial condition for the *** a given set of parameters we demonstrate that the system can end up in more than one *** example,the final state of the system may be dominated by a steady convection pattern with a fixed number of cells,however,the same system may occasionally end up in a steady pattern involving a slightly different number of cells,or it may end up in a state where most of the cells are stationary,while one or more cells end up in an oscillatory *** larger aspect ratio containers,we are also able to reproduce dislocations in the convection pattern,which have also been observed *** has been conjectured that such imperfections(e.g.,a localized star-like pattern)are due to small irregularities in the experimental setup(e.g.,the geometry of the container).However,we show,through controlled numerical experiments,that such phenomena may appear under otherwise ideal *** repeating the numerical experiments for the same non-dimensional numbers,using a different random initial condition for the temperature in each case,we are able to get an indication of how rare such events ***,we study the effect of symmetrizing the initial ***,we study the effect of selected geometry deformations on the resulting convection patterns.

关键词： B´enard-Marangoni spectral elements pattern formation